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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C. §119, of German application DE 20 2013 000 547.5, filed Jan. 18, 2013; the prior application is herewith incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to a hearing instrument housing having a plug-in connection. Such plug-in connections can be provided for instance in order to connect hearing tubes, sound tubes or electrical signal lines.
[0003] Hearing instruments can be embodied for instance as hearing devices. A hearing device is used to supply a hearing-impaired person with acoustic ambient signals which are processed and amplified in order to compensate for or treat the respective hearing impairment. It consists in principal of one or a number of input transducers, a signal processing facility, an amplification facility and an output transducer. The input transducer is generally a sound receiver, e.g. a microphone, and/or an electromagnetic receiver, e.g. an induction coil. The output transducer is usually implemented as an electroacoustic converter, e.g. a miniature loudspeaker, or as an electromechanical converter, e.g. a bone conduction earpiece. It is also referred to as an earpiece or receiver. The output transducer generates output signals, which are routed to the ear of the patient and are to generate a hearing perception in the patient. The amplifier is generally integrated in the signal processing facility. Power is supplied to the hearing device by a battery integrated in the hearing device housing. The essential components of a hearing device are generally arranged on a printed circuit board as a circuit substrate and/or connected thereto.
[0004] Hearing instruments can be embodied both as hearing devices and also as so-called tinnitus maskers. Tinnitus maskers are used to treat tinnitus patients. They generate acoustic output signals which depend on the respective hearing impairment and, depending on the working principle, also on ambient noises, the output signals possibly contributing to reducing the perception of interfering tinnitus or other ear noises.
[0005] Furthermore, hearing instruments can also be embodied as telephones, cell phones, headsets, earphones, MP3 players or other electronic telecommunication or entertainment systems.
[0006] The term hearing instrument is to be understood below to mean both hearing devices, and also tinnitus maskers, comparable devices of such types as well as electronic telecommunication and entertainment systems.
[0007] Hearing instruments, in particular hearing devices, are known in various basic types. With in-the-ear (ITE) hearing devices, a housing containing all functional components including microphone and receiver is worn at least partially in the auditory canal. Completely-in-canal (CIC) hearing devices are similar to ITE hearing devices, but are however worn completely in the auditory canal. With behind-the-ear (BTE) hearing devices, a housing with components such as battery and signal processing facility is worn behind the ear and a flexible sound tube, also referred to as tube, routes the acoustic output signals of a receiver from the housing to the auditory canal, where an earpiece on the tube is frequently provided to reliably position the tube end in the auditory canal. Receiver-in-canal, behind-the-ear (RIC-BTE) hearing devices are similar to BTE hearing devices, but the receiver is nevertheless worn in the auditory canal and instead of a sound tube. A flexible receiver tube routes electrical signals, instead of acoustic signals, to the receiver, which is attached to the front of the receiver tube, in most instances in an earpiece used for reliably positioning within the auditory canal. RIC-BTE hearing devices are frequently used as so-called open-fit devices, in which the auditory canal remains open for the passage of sound and air in order to reduce the interfering occlusion effect.
[0008] Aside from the hearing device types to be worn on or in the ear having an acoustic receiver, cochlea implants and bone conduction hearing devices (BAHA, Bone Anchored Hearing Aid) are also known.
[0009] A common aim with all hearing device types is to have the smallest possible housings and/or designs in order to increase wearing comfort, if necessary to improve the implant ability and if necessary to reduce the visibility of the hearing device for cosmetic reasons.
[0010] Hearing instruments are used to this end to generate acoustic signals which are to be made perceptible to the hearing instrument wearer. The acoustic signals are generated by loudspeakers, which are also referred to as receivers or earpieces. In this respect, the loudspeakers could be arranged in or outside of the hearing instrument housing. In hearing instruments, the housings of which are not already worn in the ear, the acoustic or electrical signals must be routed to the ear. Tube-type lines or cables are required for this, which are also referred to as sound tubes or earpiece tubes or tubes. Furthermore, input signals can also be routed to the hearing instrument housing by way of such lines, for instance from separate electronic entertainment devices.
[0011] It is desirable to detachably connect such lines to the hearing instrument housing. Therefore, detachable plug-in connections are generally provided. These plug-in connections must reliably establish contact, be protected against contamination and moisture and should not have the tendency to unintentionally detach.
SUMMARY OF THE INVENTION
[0012] The object underlying the invention consists in specifying a hearing instrument with a plug-in connection, which is reliably protected against unintentional detachment.
[0013] A basic idea behind the invention consists in a housing for a hearing instrument having a locking apparatus for a plug-in connection, which plug-in connection is formed from a plug-in connector and a plug, wherein the plug-in connector is arranged in the housing. The locking apparatus is embodied so as to prevent an unintentional detachment of the plug-in connection. The locking apparatus includes a catch, which has at least one latching plate, and which is moveably mounted in the housing between an unlocked and a locked position. The catch is moved at right angles to the plug-in direction of the plug and wherein the catch is pushed into the housing and is secured herein against unintentional sliding out by a blocking facility. The blocking facility includes a stop on the catch side and a blocking element on the housing side, against which the stop of the catch strikes when it is pushed out.
[0014] With the aid of the moveable catch, an easy-to-operate locking mechanism is achieved. In addition, uncomplicated assembly and/or manufacture is enabled by the catch being pushed into the housing. Furthermore, operation is further simplified by the catch herewith being protected against being pushed out, since there is no need to be concerned about an unintentional removal and loss of the catch.
[0015] An advantageous development of the basic idea consists in the bearing on the housing side, in which the catch can be moveably mounted, being separated from the inside of the housing. The opening needed to support the catch and for its uncomplicated installation disadvantageously also allows for the entry of impurities or moisture. Separation of the catch bearing and housing interior prevents impurities or moisture from being able to penetrate through the catch bearing to sensitive electronic components arranged in the housing.
[0016] A further advantageous development of the basic idea consists in the blocking element on the housing side being embodied as a separate component, wherein a recess for receiving the blocking element is provided in the housing. A structurally uncomplicated blocking of the catch is herewith achieved in the housing. The blocking may also be uncomplicated in terms of assembly if the housing and blocking element are provided with a snap-fit engagement for instance and the blocking element thus automatically engages in the housing.
[0017] A further advantageous development of the basic idea consists in the catch having two latching plates. On the one hand two latching plates ensure greater stability and in this respect can if necessary each be dimensioned smaller per se. On the other hand, a symmetrical arrangement can be achieved by two latching plates, thereby preventing a canting or tilting of the plug in the plug-in connector.
[0018] A further advantageous development of the basic idea consists in a recess for receiving a holding element of the plug being provided in the plug-in connector. Such a recess, in cooperation with the aforesaid locking mechanism, provides a structural requirement for a simple-to-operate and reliably closing plug-in connection.
[0019] A further basic idea of the invention consists in a plug for a plug-in connector of a housing, such as the hearing instrument explained in detail above, wherein the plug has at least one latching plate stop, which is arranged such that it allows for insertion of the plug into the plug-in connector, if the catch is in the unlocked position, and which, when the plug is pulled from the plug-in connector, strikes against the latching plate if the catch is in the locked position.
[0020] With the aid of the latching plate stop, an easy-to-operate locking process is achieved. In addition, uncomplicated installation and/or manufacture is enabled by the catch being pushed into the housing. Furthermore, operation is further simplified by the catch being protected against being pushed out, since there is no need to be concerned about an unintentional removal and loss of the catch.
[0021] An advantageous development of the basic idea consists in the latching plate stop having a lower mechanical stability than the latching plate, the catch and the bearing of the catch in the housing of the hearing instrument, such that when the plug is pulled out from the plug-in connector, if the catch is in the locked position, the latching plate stop breaks before the said further components become damaged. A rupture joint is produced in this way, which ensures that neither the housing nor the catch on the housing side are damaged as a result of damaged caused by faulty operation of the plug. The plug is less expensive and can be easily replaced. Furthermore, plugs of this type are generally replacement parts provided for replacement purposes, and are therefore advantageously easily available.
[0022] A further advantageous development of the basic idea consists in the catch having two latching plate stops. On the one hand two latching plate stops ensure greater stability and in this respect can if necessary each be dimensioned smaller per se. On the other hand, a symmetrical arrangement can be achieved by two latching plate stops, thereby preventing a canting or tilting of the plug in the plug-in connector.
[0023] A further advantageous development of the basic idea consists in the plug having a holding element which is embodied so as to engage in the counter bearing provided herefor in the plug-in connector upon insertion of the plug into the plug-in connector. Together with the aforesaid recess and in cooperation with the aforesaid locking mechanism, such a holding element provides a structural requirement for a simple-to-operate and reliably closing plug-in connection.
[0024] A further advantageous development of the basic idea consists in the plug being connected to one end of a tube, and upon insertion of the plug into the plug-in connector, closing at least one electrical and/or acoustic connection between the housing and the tube, and wherein the tube includes at least one electrical and/or acoustic line. The plug-in connection is thus advantageously suited to a BTE hearing device or a RIC-BTE hearing device.
[0025] A further basic idea of the invention consists in a hearing instrument having a housing embodied as explained above and a plug embodied as explained above. A BTE hearing device or a RIC-BTE hearing device with a plug-in connection is thus advantageously produced with an easy-to-operate locking mechanism. In addition, uncomplicated assembly and/or manufacture is enabled by the catch being pushed into the housing. Furthermore, operation is further simplified by the catch being protected against sliding out, since there is no need to be concerned an unintentional removal and loss of the catch.
[0026] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0027] Although the invention is illustrated and described herein as embodied in a hearing instrument housing having a plug-in connection, a plug and a hearing instrument, 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.
[0028] 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 SEVERAL VIEWS OF THE DRAWING
[0029] FIG. 1 is a diagrammatic, perspective view of a hearing instrument with a housing and a plug;
[0030] FIG. 2 is a perspective, partial view of the housing with a separate catch;
[0031] FIG. 3 is a perspective, partial view of the housing with a catch in a locked position;
[0032] FIG. 4 is a perspective, partial view of the housing with the catch in an unlocked position; and
[0033] FIG. 5 is a perspective view of the plug with a latching plate stop.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a perspective representation of a hearing instrument 1 with a housing 2 and a plug 3 . A tube 4 , not shown completely, attaches to the plug 3 .
[0035] The housing 2 includes a locking mechanism, which is mostly concealed by the housing 2 and the plug 3 and can thus not be identified in FIG. 1 . Only the end of a moveable catch 6 protrudes from the housing 2 . The plug 3 is inserted into a plug-in connector 5 of the housing.
[0036] Further features of the housing 2 are not required to explain the invention and are therefore not referred to in more detail.
[0037] FIG. 2 shows a perspective representation of the housing 2 without the plug 3 and with a removed, separate catch 6 . Only the region of the housing 2 in which the plug-in connector 5 is arranged is shown here.
[0038] In the broadest sense 5 , the plug-in connector 5 is embodied as a socket and/or female connector, into which the plug 3 can be inserted. A receptacle 14 for a holding element of the plug 3 can be seen in the region of the plug-in connector shown below. The receptacle 14 , which is not visibly shown in the figure, is embodied as an undercut, below or behind which a holding element of the plug can be pushed.
[0039] A locking apparatus is arranged on the side of the plug-in connector 5 facing the receptacle 14 . The locking apparatus includes the catch 6 as an essential component. The catch 6 has two latching plates 9 , the function of which is explained again below.
[0040] In addition, the catch 6 has a stop 10 . The catch 6 is pushed into a bearing in the housing 2 embodied as a catch guide 8 . Once the catch 6 is completely pushed into the catch guide 8 , the stop 10 is disposed in the region of a counter bearing 15 . A blocking element 7 is used there as soon as the catch 6 is pushed in. The blocking element 7 with the edge shown to the left in FIG. 3 prevents the catch 6 from being able to be pushed out of the housing 2 , by the stop 10 striking against the edge of the blocking element 7 .
[0041] As explained again below, the catch 6 , provided it is pushed fully into the housing 2 and is installed in the blocking element 7 , still has a limited mobility, so as to be able to be moved between a locked and an unlocked position.
[0042] The catch guide 8 which supports the catch 6 moveably in the housing 2 , although it represents an opening in the housing 2 , is not connected to the interior of the housing 2 . Impurities and moisture can in this way only pass through the opening in the catch guide 8 into the catch guide 8 and not from there to sensitive components, which are arranged inside the housing 2 .
[0043] The blocking element 7 , which, after the catch 6 is pushed in, is inserted into the counter bearing 15 , engages, as described, with its edge facing the catch-side stop 10 , into the stop 10 and/or the recess in the region of the stop 10 .
[0044] The blocking element 7 is embodied as a separate component, which is not permanently connected to the housing from the outset. It can be glued in the region of the counter bearing 15 for instance. The counter bearing 15 can advantageously be embodied such that it makes a re-releasable, form-fit connection with the blocking element 7 , the connection possibly being embodied as a snap-in or clip-in closure.
[0045] In a further non-illustrated embodiment, the blocking element 7 can also be rigidly connected to the housing 2 and can be integrated there as an elastic snap-fit engagement, for instance locking pin. Such an embodiment would however render necessary a more complex form of the housing 2 , which would be more complicated in terms of manufacture, but would however on the other hand be advantageous in that the blocking element 7 is not a separate, loose component, which can get lost. Since however the blocking element 7 does not have to be removed for everyday use of the hearing instrument 1 , detachment and loss of the same is improbable, so that the embodiment of the blocking element 7 shown in the figure as a separate, loose component does not represent any major disadvantage.
[0046] In FIG. 3 the housing 2 including the catch 6 is shown schematically in the locked position of the catch 6 . In the locked position, the catch 6 is pushed completely into the housing 2 , in other words, is flush with the outer side of the housing wall. The blocking element 7 is installed in the housing 2 , so that the catch 6 is protected against being pushed out from the catch guide.
[0047] In the completely pushed-in, locked position of the catch 6 , the latching plates 9 are likewise pushed in as far as possible, in other words, likewise into their locked position. The latching plates 9 effect a locking of the plug connection, in other words, of the plug 3 in the plug-in connector 5 in the manner to be explained again below.
[0048] In the figure shown, the plug 3 is however not inserted.
[0049] FIG. 4 shows the housing 2 and the catch 6 in an unlocked position. The end of the catch 6 protrudes in a non-flush manner beyond the outer wall of the housing 2 .
[0050] As above, no plug 3 is likewise inserted in the plug-in connector 5 . However, in the unlocked position of the catch 6 shown, the plug 3 could be both inserted and also pulled out of the connector. This is because the latching plates 9 , of which only one can be seen in the selected view, are likewise disposed in their unlocked position. In other words, the latching plates 9 , in the unlocked position of the catch 6 , release the path for insertion or removal of the plug 3 .
[0051] In the unlocked position of the catch 6 shown, this is pulled out as far as the blocking element 7 allows. This end position of the catch 6 is predetermined in that the stop 10 on the catch side strikes the adjacent edge of the blocking element 7 . In other words, the blocking element 7 blocks a passage of the stop 10 and thus prevents further movement of the catch 6 . When the blocking element 7 is installed, the catch 6 can thus be moved between the fully inserted, locked position, and the pushed-out, unlocked position shown.
[0052] FIG. 5 shows a perspective representation of the plug 3 with latching plate stops 11 . The plug is connected to the tube 4 , which is not reproduced in its entirety. It has a holding element 12 , which, in order to insert the plug into the aforesaid plug-in connector 5 of the housing 2 , is pushed in such that it is moved below the receptacle 14 embodied as an undercut. As a result, the side of the plug 3 , on which the holding element 12 is arranged, is held in the plug-in connector 5 and protected against a sliding out or pulling out of the plug 3 .
[0053] The latching plate stops 11 are arranged on the side of the plug 3 facing the holding element 12 . These are moved past the latching plates 9 upon insertion of the plug 3 into the plug-in connector 5 . To this end, the catch 6 , as shown above, must be in the unlocked position. On the other hand, the latching plates 9 block the path of the latching plate stops 11 upon insertion of the plug.
[0054] Once the plug 3 is completely inserted into the plug-in connector 5 , the catch 6 , in the locked position, can be push into the housing 2 and/or the catch guide 8 completely. As a result, the latching plates 9 of the catch 6 mutually engage with the latching plate stops 11 of the plug 3 .
[0055] In the perspective selected in the figure, the latching plates 9 of the catch 6 slide, upon locking, across the edge visible at the top of the latching plate stop 11 which can be seen on the left. In the same way, the further latching plate 9 moves over the latching plate stop 11 which is not fully visible. As a result, the plug on the side in the plug-in connector 5 facing the holding element 12 is protected against pulling out or sliding out. In this way the plug-in connection produced by the plug 3 and the plug-in connector 5 is protected and/or locked against unintentional detachment.
[0056] In order to prevent damage due to inappropriate tensile stress of the plug 3 , e.g. by way of the hose 4 , the latching plate stops 11 are embodied as rupture points. To this end, they are embodied to be mechanically less stable than the latching plates 9 and the catch 6 and the catch guide 8 in the housing 2 . As a result, the latching plate stops 11 break in the case of an excessive tensile stress, before the catch 6 or the housing 2 break and/or can cause damage. As soon as the latching plate stops 11 are broken for the first time, the plug 3 is no longer locked in the plug-in connector 5 , and can therefore be slid out and/or pulled out.
[0057] The embodiment of the latching plate stops 11 in the manner described as rupture points can be achieved on the one hand by a sufficiently small dimensioning of its geometric dimensions. On the other hand, lateral narrower sections or webs can be integrated into the outer shape of the latching plate stops 11 , this is not shown in the figure. Furthermore, they can be manufactured from softer or more fragile material compared with the components to be protected, in other words above all catch 6 and housing 2 .
[0058] The contact area of the plug is disposed on the side of the plug 3 facing the housing 2 , upon insertion of the plug 3 , in the figure shown below. It is surrounded by a sealing lip 13 which can be seen in the figure. Both electrical and also acoustic contact elements, which are used to electrically or acoustically connect the plug 3 to the housing, can be found in the contact region.
[0059] Upon insertion of the plug 3 , these electrical or acoustic connections with the housing 2 are closed. For instance, an earpiece can be arranged in the housing 2 , the acoustic output signals of which are routed via a connection of this type through the plug 3 into the tube 4 . Similarly, an amplifier can be arranged in the housing 2 , the electrical output signals of which pass through the plug 3 into the tube 4 . The electrical or acoustic signals can be routed through the tube 4 to an earpiece for instance, which is worn as intended in an auditory canal of a hearing instrument wearer.
[0060] Conversely, the plug 3 can however also be provided to supply electrical or acoustic signals coming from the tube 4 or originating from an external source to the housing 2 of the hearing instrument 1 . | A hearing instrument has housing with a plug-in connection. The plug-in connection connects hearing tubes, sound tubes or electrical signal lines. The hearing instrument ensures against an unintentional detachment of the tubes and lines from the housing. The housing has a locking apparatus. The plug-in connection is arranged in the housing. The locking apparatus is embodied to prevent an unintentional detachment of the plug in the plug-in connection. The locking apparatus includes a catch, with a latching plate, and being moveably mounted in the housing. The catch moves at right angles to the plug-in direction of the plug and the latch is pushed into the housing and is protected herein by a blocking facility against unintentionally being pushed out. The blocking facility includes a stop and a blocking element, against which the stop strikes when sliding out. With the moveable catch, an easy-to-operate locking process is achieved. | 7 |
REFERENCE CITED
U.S. Patent Documents
5,983,909
11/1999
Oh Eui Yeol et al
6,506,428 B1
1/2003
Berge et al
FIELD OF THE INVENTION
The present invention relates generally to the disinfection of microbes including viruses, bacteria and fungi, but particularly, for the process of sterilizing biological warfare agents contaminating vast regions in the event of a release of agents in the environment, civilians or facilities. The biological warfare contaminants are eliminated by their exposure to the acidic ozone water. The present invention also shows that the acidity and ozone in the seawater sterilize microbes effectively, demonstrating a potential for the sterilization of a large amount of seawater in a short time.
BACKGROUND OF THE INVENTION
Biological warfare agents if released pose a great harm to mankind. Biological warfare agents including bacterial endospores like Bacillus anthracis , vegetative bacterial cells like Vibrio cholera and viruses like smallpox have been used in the past and will also be used in future military conflicts between nations and terrorists. Particularly, there were several incidents of bioterrorism in the fall of 2001 after the events of September 11, when preparations of Bacillus anthracis were mailed to public and private institutions, leading to 5 deaths and having a profound effect on the national psyche. The cost of decontamination and remediation of these attacks was very high. The main decontamination processes of these anthracis attacks were stripping and fumigation using chlorine dioxide, which is a toxic substance.
Elimination of unwanted microbes in seawater may be very useful in the shipping and fish-farming industries. World coastlines are contaminated by foreign biological species from ships' ballast water, disturbing local ecological systems. For example, copepods, native to Japan, China and Korea, appeared first in the Colombia River in 1990 have now spread to all of the west coast rivers in North America, displacing native copepods. European mussels brought by ships invaded the five great lakes in the US, causing great damage to hydro-electric power plants and factories. According to the US Coast Guard, the US spent more than 1 billion dollars to rectify this situation. In fact, the world sterilization cost of the pollution caused by ballast water is approximately 10 billion dollars annually. The International Maritime Organization decided that ballast water must be sterilized before discharging in order to prevent the spreading of foreign biological species and to protect the local ecological system. The fish-farming industries use various chemicals to kill bacteria, viruses and fungi, and these chemicals can harm fish populations and human. One of the notorious chemicals used in fish-farming industry is Malachite green, a carcinogenic material. Sterilizing unwanted microbes in seawater without the use of toxic chemicals is required.
Ozone is very effective in sterilizing microbes. Ozone after sterilization disintegrates into oxygen without leaving any harmful materials to environment. The difficulties associated with ozone are its finite lifetime in water and efficiency. In this context, properties of ozone in water have been investigated. Particularly, the ozone decay time in water was measured for a broad range of physical parameters including several values of ethanol concentration and different pH values. The increase of ozone decay time by lowering the pH value of the water was observed. It was also noted that the decay time decreases drastically as the ethanol concentration increases.
Assuming that N represents the microbe number in unit volume, the number of microbes killed per unit time and unit volume by acidic ozone water can be represented by
ⅆ N ⅆ t = - N [ α n O 3 exp ( - t τ ) ] , ( 1 )
where n O3 is the initial ozone density, and α is the inactivation coefficient of ozone in units of L/(mg·s). Ozone (αn O3 ) in acidic ozone water in Eq. (1) inactivates the microbes. Integration of Eq. (1) over time t gives the density of microorganisms in terms of time t:
log ( N ( t ) N 0 ) = - 0.43 α n O 3 τ [ 1 - exp ( - t / τ ) ] , ( 2 )
where the constant N 0 represents the initial density of microorganisms. As can be seen from the theoretical model in Eq. (2), the concentration (n O3 ) of ozone and its decay time (τ) are the critically important factors on the sterilization. Increase of the ozone decay time (τ) enhances the sterilization effects. The theoretical model developed in Eq. (2) for sterilization of microbes by ozone in water indicates that the main synergic effect of the acidity in water is the increase of the ozone decay time at a low pH value, thereby effectively killing endospores of Bacillus atrophaeus , demonstrating a potential for sterilization of microbes on a large contaminated area in a very short time and reinstating the contaminated environment as free from biological agents.
The purpose of the present invention is to develop a rapid and effective eliminating method of toxic biological warfare agents from large contaminated areas in the event of a release of agents on the environment, civilians or facilities. The acidic ozone water (AOW) can be produced abundantly in various forms like solutions, foams with substances, as well as mist and fog to satisfy a wide variety of operational objectives and can be retrofitted into many existing decontamination apparatus. The ozone in the acidic ozone water decays reasonably fast into oxygen without any trace after the decontamination process. The acidic water after the decontamination process can also be neutralized without any burden to the environment. Therefore, the acidic ozone water may be a good candidate for a mass sterilization of toxic biological warfare agents.
The acidic ozone water was proposed in the U.S. Pat. No. 5,983,909 issued to Oh Eui Yeol et. al. on Nov. 16, 1999. In that invention, an aqueous oxidizing acidic cleaning solution is produced by mixing an acidic solution with ozone water. An aqueous reducing acidic cleaning solution is produced by mixing an acidic solution with hydrogen water. The aqueous cleaning solution has effective cleaning power. Therefore, by selecting an appropriate aqueous cleaning solution according to the types of contaminants adhering to subjects during each manufacturing step, a plurality of types of contaminants can be removed by washing with this aqueous cleaning solution. On the other hand, the present invention makes use of synergic benefits derived from the combination of ozone and acidity in the acidic ozone water with a low pH value for sterilization of microbes instead of cleaning subjects.
The ozone and acidity in the acidic ozone water kill the microbes and then disintegrate into oxygen and ordinary water without leaving any trace of them as time goes by, thereby being harmless to the environment. The acidic ozone water therefore must be used to sterilize the contaminated area as soon as it is produced. This property is beneficial to the environment but limits applications of the acidic ozone water to broad areas because of ozone disintegration. Ozone dissociation in water is initiated by the negative OH ions, whose number increases faster with the pH value of the acidic water. For example, the ozone decay time (τ) in the acidic ozone water with the pH value of 4 is about twice as long than that in ordinary fresh water with a pH value of 7. Therefore, it is much easier for a low pH value to make the ozonated water with high ozone concentration.
The ozone molecules disintegrate into oxygen molecules as they meet the negative OH ions or any other organic contaminants in water. The translational motion of the molecules in the water becomes faster as the water temperature increases. Ozone molecules have a higher chance of meeting the negative OH ions or other contaminants as the water temperature T increases. Accordingly, the ozone decay time τ in the acidic ozone water increases as the water temperature T decreases. The ozone in the acidic ozone water decays slowly if the water temperature is less than 4 degree Celsius. The chilled acidic ozone water preserves its properties long after its creation. The slowly decaying ozone molecules, before their disintegration, in the chilled acidic ozone water have a better chance of meeting and killing microbes.
Ice is the water crystal produced from freezing water. Ozone molecules, the positive hydrogen ions, the negative OH ions, and other contaminants in the acidic ozone ice are embedded inside the ice crystal. The positive hydrogen ions, whose density represents the acidity in the acidic ozone water, cannot move freely in ice, thereby preserving the ice acidity almost permanently. The ozone molecules in the acidic ozone ice are not allowed to meet the negative OH ions or any other contaminants in the ice, so that the ozone decay time τ becomes infinite in the acidic ozone ice. The ozonated ice was proposed in the U.S. Pat. No. 6,506,428 B1 issued to Berge and McClure on Jan. 14, 2003. In that invention, the ozonated ice was made for the disinfections of microbes by melting it as needed. The present invention extends the ozonated water concept in the previous U.S. Pat. No. 6,506,428 B1 to the acidic ozone water. The acidic ozone ice preserves its strong sterilizing-character permanently.
It is therefore an important object of the present invention to enhance the sterilizing strength of the acidic ozone water in order to achieve the elimination of toxic biological warfare agents in the contaminated area by exposing it to the ozone and acidity simultaneously in the acidic ozone water.
Another object of the present invention is to provide synergic benefits derived from the combination of ozone and acidity in the acidic ozone water for the sterilization of microbes on a large surface area contaminated by biological warfare agents.
One other object of the present invention is to provide synergic benefits derived from the combination of ozone and acidity in the acidic seawater for the sterilization of a large amount of seawater in a short time.
One additional object is to overcome the difficulties associated with the ozone decay in the acidic ozone water, and heretofore experienced in achieving efficient and rapid elimination of the toxic biological agents by chilling or freezing the acidic ozone water.
Additional objects, advantages and novel features of the invention will be explained in part in the following description, and will be apparent to those skilled in the following experiment.
SUMMARY OF THE INVENTION
The present invention is the method for the disinfections of microbes including viruses, bacteria and fungi with the acidic ozone water. Particularly, the present invention relates to a process for sterilizing biological warfare agents contaminating large surface areas in the event of a release of agents on the environment, civilians or facilities. The biological warfare contaminants are eliminated by their exposure to the acidic ozone water. The present invention also shows that the acidity and ozone in the seawater sterilize microbes effectively, demonstrating a potential for the sterilization of a large amount of seawater in a short time. Furthermore, the present invention provides the method of overcoming difficulties associated with the ozone decay in the acidic ozone water by chilling or freezing it.
The acidic water is made from neutral water by mixing acidic materials. Mixing a small amount of acid like hydrochloric acid (HCl) into water produces the acidic water. The acidity of the acidic water is represented by pH value. The neutral fresh water has pH value of 7. On the other hand, the natural seawater is slightly alkalic and has pH value of 8.2. The acidity of the acidic water increases as the pH value is lowered further down from 7 for fresh water or from 8.2 for seawater. The pH value of the acidic water was measured in terms of the mixing ratio of the hydrochloric acid. FIG. 1 is plots of the pH value versus the concentration of the hydrochloric acid in units of milli-mole per liter (mM/L) for three different waters, deionized water, tap water supplied from a municipal water supply system and seawater. The square dots represent the acidity of the acidic water from deionized water, circular dots represent the acidity of the acidic water made from the tap water, and triangular dots represent the acidity of the acidic seawater. Note in FIG. 1 that the pH value of the neutral seawater without any concentration of the acid is pH=8.2. The pH value of the acidic waters in FIG. 1 decreases as the concentration of the hydrochloric acid increases, thereby enhancing the acidity. The pH value in the acidic seawater has very peculiar profile in terms of the concentration of the hydrochloric acid. This peculiar property may be caused by various ions existing in the seawater, including sodium and chlorine ions. One ton of acidic water with its pH value of 4 made from tap water as represented by circular dots in FIG. 1 may require 0.6 mole of the hydrochloric acid, which is equivalent to 22 grams of the acid. Obviously a very small amount of acid is needed for making the acidic water from a tap water. The acidity of pH value of 4 is similar to the cola acidity and is also used for baby skin care. It is also noted from FIG. 1 that one ton of acidic seawater with its pH value of 6 made from seawater may require 1.5 mole of the hydrochloric acid, which is equivalent to 55 grams of the acid. Obviously a very small amount of acid is also needed for making the acidic seawater from plain seawater. One liter of seawater contains 35 grams of salt, which is equivalent to 0.54 moles. Thus, the mole fraction of the hydrochloric acid to the salt concentration in the acidic seawater with its pH=6 is 0.0027, which is negligibly small.
An ozone generator of corona discharge type produces a high ozone concentration gas, which is injected into a porous ceramic diffuser submerged into the acidic water that generates acidic ozone water (AOW). The ozone gas can also be dissolved into the acidic water by an ozone mixture device based on the Bernoulli effects, which mixes tiny bubbles of ozone gas with the water, dissolving about 60 percent of ozone into water. The dissolved ozone concentration in AOW is in the range of 0.1˜100 milligrams per liter (mg/L) measured by an ultra violet spectroscopy.
Biological warfare agents like viruses or bacteria attach themselves to organic or inorganic aerosols and are spread when aerosol particles float around, eventually settling on surfaces of various objects with abundant organic compounds. Most of the ozone molecules in the acidic ozone water have disappeared due to the interaction with organic compounds in the vicinity of microbes. Only a fraction of ozone in the acidic ozone water participates in the killing activity of biological warfare agents. In this context, the ozone concentration in the acidic ozone water must be considerably higher than expected and the pH value of the acidic water must be significantly lower for the sterilization of contaminated areas with biological warfare agents. In other words, the ozone decay time τ and killing rate associated with acidity in the environment of abundant organic compounds in the real world are much less than the expected values in a controlled experiment without organic contaminations. The acidic ozone water can be sprayed over a large surface area contaminated with biological warfare agents. The acidic ozone water can also effectively kill other ordinary microbes of viruses, bacteria, and fungi, hence being applicable to agriculture, seafood and livestock industries for the preservation of various products as well as being useful in hospitals or other germ infested areas for disinfections. Furthermore, the ozone in the acidic seawater sterilizes very effectively a large amount of seawater in a short time.
BRIEF DESCRIPTION OF DRAWING FIGURES
A more complete appreciation of the invention and many of its attendant advantages will be aided by reference to the following detailed description in connection with the accompanying drawings:
FIG. 1 is plots of the pH value versus the concentration of the hydrochloric acid in units of milli-mole per liter (mM/L) for three different waters, deionized water, tap water supplied from a municipal water supply system and seawater. The square dots represent the acidity of the acidic water from deionized water, circular dots represent the acidity of the acidic water made from the tap water, and triangular dots represent the acidity of the acidic seawater.
FIG. 2 is a block diagram illustrating the method of sterilizing microbes of the present invention.
FIG. 3 is plots of the survival curves for B. atrophaeus endospores exposed to bactericidal formulation, AOW, with the pH value of 4, 5, and 7 for ethanol concentration of 0.072 mole/L. The vertical axis is the log of the ratio of the number of viable spores remaining (N) to the control number of N 0 . Dots are experimental data and curves are obtained theoretically from Eq. (2).
FIG. 4 is plots of the survival curve for B. atrophaeus endospores exposed to seawater with a 5 mg/L ozone concentration at several different pH values. The horizontal scale represents the ozone decay time τ measured in seconds corresponding to the specific pH value of seawater contaminated by an ethanol concentration of 7.7 mM/L.
DETAILED DESCRIPTION
The present invention is the method for disinfections of microbes including viruses, bacteria and fungi with the acidic ozone water. Particularly, the present invention relates to an apparatus and process for sterilizing biological warfare agents contaminating large surface areas in the event of a release of agents on the environment, civilians or facilities. The present invention also relates to an apparatus and process for sterilizing microbes in a large amount of seawater. The principles and operation of the method for disinfections of microbes of the present invention are described according to the drawings.
Referring now to the drawing in details, FIG. 2 diagrams water supply 10 and acid supply 20 that provide water and acid to the acid mixing unit 30 , mixing the acid into water and generating the acidic water. The acidic water from the acid mixing unit 30 enters the ozone mixing unit 60 . The ozone generator 50 converts oxygen from an oxygen tank 40 or an air compressor to an ozone-rich gas, which enters the ozone mixing unit 60 . A typical ozone mixture device based on the Bernoulli effects mixes tiny bubbles of ozone gas with the water, dissolving about 60 percent of ozone into water. The ozone mixing unit 60 converts the acidic water to the acidic ozone water by dissolving ozone into acidic water. The spray nozzle 80 sprays the acidic ozone water over a large surface area contaminated with biological warfare agents, sterilizing the toxic warfare agents.
The acidic ozone water from the ozone mixing unit 60 can also be used for the disinfections of ordinary microbes of viruses, bacteria and fungi, which may cause the deterioration of products in agricultural, seafood and livestock industries. The acidic ozone water may be used for the sterilization of microbes in products from drug manufacturing industries. The acidic ozone water from the ozone mixing unit 60 can also be sprayed over farmlands or livestock sheds to control diseases by disinfecting disease-causing microbes. The acidic ozone water may also be useful in hospitals or other germ-infested areas for disinfections. The ozone and acidity in the acidic ozone water made from seawater also sterilize microbes in the seawater.
The acidic ozone water from the ozone mixing unit 60 enters the chilling and freezing unit 70 to be chilled or to be iced. The chilled acidic ozone water holds its ozone concentration and acidity for a long time after its production from the ozone mixing unit 60 , thereby keeping its capability of sterilizing microbes for a long time. The acidic ozone ice from the chilling and freezing unit 70 preserves its ozone concentration permanently. The acidic ozone ice from an ice maker in the chilling and freezing unit 70 is distributed to one or more locations remote from the ice maker for sterilization or disinfections of microbes through routine ice delivery routes.
As mentioned earlier, a rapid and effective elimination of toxic biological warfare agents from a large contaminated area is the key issue in life threatening situations. In this context, the acidic ozone water must be produced abundantly within a short period of time. The acidic water can be generated from a tap water supplied by a municipal water supply system. The acidic water can also be generated from seawater abundant in earth. A typical ozone generator 50 operated by 40 kilowatts can produce ozone for more than 2 kg per hour, which is enough for the production of 1000 lpm of the acidic ozone water with an ozone concentration of 20 mg/L. For example, 1000 lpm of the acidic ozone water with the pH value of 3.8 and the ozone concentration of 20 mg/L from a moderate AOW apparatus can be sprayed over a large infected area, sterilizing the biological warfare agents.
EXAMPLE 1
The focus of the sterilization study is mostly on the decontamination of bacterial endospores because they are recognized to be the most difficult microorganisms to kill. The decontamination experiment of the bacterial endospores was carried out by using spores of Bacillus atrophaeus ( B. Subtilis var. niger, ATCC 9372). In order to observe the influence of organic compounds on the ozone concentration and its kill properties, the original bacillus-spore suspension was made of a high concentration (40% by weight) of ethanol, which is harmless to spores. The spore concentration of the original spore suspension was 10 7 ˜10 8 spores per milliliter (mL). The spore treatment experiments were conducted by adding 0.1 mL of spore suspension with 10 mL of the acidic ozone water with three different pH value of 4, 5 and 7. The acidic ozone water in this example is made of a tap water supplied from a municipal water supply system. The ozone concentration in AOW was 20 mg/L. The concentration of ethanol in 10 mL of AOW is calculated to be 0.072 mole/L. Ozone in water decayed very fast with this ethanol concentration.
One mL of the solution was obtained from each sample after a specified contact time and was diluted with 9 mL of distilled water. FIG. 3 shows the survival curves for B. atrophaeus endospores exposed to bactericidal formulation, AOW, with the pH value of 4, 5, and 7 for ethanol concentration of 0.072 mole/L. The vertical axis is the log of the ratio of the number of viable spores remaining (N) to the control number of N 0 . Each point in FIG. 3 represents an average value of 3 data. The untouched control was also analyzed every time to get the average control number N 0 =2.5×10 6 , corresponding to log N 0 =6.4. The error bars in FIG. 3 were obtained from the square root of the second moment of data around its mean value at each contact time. The ozone in the acidic ozone water decayed faster within 1 minute with the decay time being less than 30 seconds due to ethanol contamination. Therefore, most of the killing action in the acidic ozone water occurred within 1 minute as expected. Keeping in mind N 0 =2.5×10 6 , it is noted that most of the spores were killed within 2 minutes by contact of the acidic ozone water at low pH value.
The curves in FIG. 3 represent the log reduction of live microbes versus time t in seconds for the acidic ozone water, obtained from Eq. (2) for AOW, n O3 =20 mg/L, and τ=8.1 s for pH=7, τ=23 s for pH=5 and τ=26 s for pH=4. These ozone decay times were measured values for the ethanol concentration of 0.072 mole/L. The parameter α=0.0215 L/(mg·s) in obtaining curves here was the least-squares fitted to the experimental data (triangular dots) for pH=7 in FIG. 3 . Note that the ozone decay time τ increases from z=8.1 s for pH=7, to τ=23 s for pH=5 and τ=26 s for pH=4 in AOW at the room temperature of 25° C. The short decay time τ=8.1 s in AOW with pH=7 is for a situation in which the environment contains many organic compounds represented by ethanol concentration of 0.072 mole/L corresponding to 3.4 g/L. The ozone concentration of 20 mg/L is far less than the ethanol concentration. However, 20 mg/L ozone concentration is equivalent to 1.4×10 17 molecules/cm 3 , which is much higher than the spore concentration in the order of 10 6 /cm 3 . It is observed from FIG. 3 that the log of the ratio of N to N 0 for the acidic ozone water in experimental data agrees remarkably well with the theoretical curves.
EXAMPLE 2
The sterilization of microbes in seawater was carried out by using the ozone and acid in the seawater. The spore concentration of the original spore suspension was 10 5 ˜10 6 spores per mL. The spore-treatment experiments were conducted by adding 0.2 mL of spore suspension to 10 mL of seawater at a specified pH value and ozone concentration of 5 mg/L. The concentration of ethanol in the mixture of 0.1 mL of spore suspension and 10 mL of seawater was 7.7 mM/L. Ozone in the water decayed rapidly with this ethanol concentration. For example, the ozone decay time τ in the seawater with its ethanol concentration of 7.7 mM/L was measured to be τ=22 s for pH=8, τ=40 s for pH=7, τ=70 s for pH=6 and τ=90 s for pH=5. One mL of the solution was obtained from each sample after 40 minutes of contact time and was diluted with 9 mL of distilled water. The contact time t=40 minutes is much longer than the ozone decay time τ less than 2 minute for the case of high concentration of ethanol. Equation (2) is further simplified to
log ( N ( t ) N 0 ) = - 0.43 α n O 3 τ ( 2 )
for t>>τ typical to the sterilization of microbes in seawater. FIG. 4 shows the survival curve for B. atrophaeus endospores exposed to seawater with a 5 mg/L ozone concentration at several different pH values. The horizontal scale represents the ozone decay time τ measured in seconds corresponding to the specific pH value of seawater contaminated by an ethanol concentration of 7.7 mM/L. The vertical axis is the log of the ratio of the number of viable spores remaining (N) to the control number of N 0 . The untouched control was also analyzed each time to obtain the average control number N 0 =3.3×10 5 , which corresponded to log N 0 =5.52.
The dots in FIG. 4 represent the experimental data of the log reduction of live microbes versus the ozone decay time τ in seconds for seawater with an ozone concentration of 5 mg/L and contaminated by an ethanol concentration of 7.7 mM/L corresponding to 360 mg/L. In effect, all of the spores were killed at τ=90 s, but one surviving spore at τ=90 s was assumed for convenience regarding the log scale plot shown in FIG. 4 . The molecular number of ethanol in this seawater is 150 times greater than that of ozone. The straight line in FIG. 4 was obtained from Eq. (3) and was linearly fitted to the experimental dots (squares) with the parameter αn O3 =0.135/s, which was the least-squares value fitted to the experimental data in FIG. 4 . Assuming an initial ozone concentration of n O3 =5 mg/L, the inactivation coefficient of ozone was calculated to be α=0.027 L/(mg·s) for αn O3 =0.135/s. The short decay time τ in FIG. 4 represents a situation in which the seawater contains many organic compounds. On the other hand, for relatively clean seawater in an application to ballast water, the organic material is less than 5 mg/L and the ozone decay time at pH=7 is 3.3 minutes. Equation (3) predicts the viable B. spore number of N=8 for N 0 =3.3×10 5 at an ozone concentration of n O3 =2 mg/L.
It is observed from FIG. 4 that the log of the ratio of N to N 0 for the acidic seawater in the experimental data is in good agreement with a theoretical model. The ozone decay time of τ=90 s at pH of 5 is four times that at a pH of 8. Therefore, an increase of the ozone decay-time by lowering the pH value must play a pivotal role in the killing process. Similar sterilization may be achieved by a four-fold increase in the ozone concentration in seawater at pH=8. However, an ozone concentration of 20 mg/L in seawater may be impractical for application to sterilizations. Hence, a reasonable ozone concentration at a low pH value may make it possible to sterilize a large amount of seawater in relatively little time, freeing this water from unwanted microbes. FIG. 4 clearly demonstrates that an increase of the ozone decay time at a low pH has the most important synergic effect on the sterilization of microbes in seawater. | This invention is directed to a sterilization method of contaminated areas with biological agents by making use of the acidic ozone water that very effectively kills spores of Bacillus atrophaeus , thereby demonstrating the capability of sterilizing a large surface-area in a very short time and reinstating the contaminated environment as free from toxic biological agents. The effective sterilization of the acidic ozone water is due to synergic benefits derived from the combination of ozone and acidity. The acidic ozone water can also effectively kill other ordinary microbes of viruses, bacteria, and fungi, hence being applicable to agriculture, seafood and livestock industries for the preservation of various products as well as being useful in hospitals or other germ infested areas for disinfections. Particularly, the acidity and ozone in the seawater sterilize microbes effectively, demonstrating a potential for the sterilization of a large amount of seawater in a short time. After the decontamination process, the acidic ozone water disintegrates into water and oxygen without any trace of harmful materials to the environment. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a solid polymer electrolyte for use in electro-chemical devices such as a primary battery, a secondary battery, an electro-chromic display, an electro-chemical sensor, an iontophoresis, a condenser and others.
A solid polymer electrolyte having a crosslink network structure is well known. This crosslink network structure has been formed by using polyethylene glycol or polyether including a molecular weight of smaller than 2,000. The polyethylene glycol has a high ability to dissolve alkaline metal salt, but has a defect that it is liable to crystallize. Further, a solid polymer electrolyte having a structure formed by denaturing and cross-linking the above polyethylene glycol and polyether into ester diacrylate or ester dimethacrylate has the defect that they are inflexible and very brittle. For this reason, it is apt to be broken by an external force to cause short-circuiting, etc. when used in a battery. Especially, the flexibility will be worsened as the molecular weight of polyethylene glycol becomes small. Polyethylene glycols having a molecular weight of smaller than 2,000 have so far been used, and especially those having a molecular weight ranging from 200 to 1,000 have been used in order to avoid crystallizing. Therefore, the defect of poor flexibility has been remarkable.
SUMMARY OF THE INVENTION
An object of this invention is to provide a solid polymer electrolyte having a good flexibility, i.e. excellent mechanical properties, and including a high ionic conductivity.
A first embodiment of the invention provides a solid polymer electrolyte including an ionic salt and a compound able to dissolve the ionic salt and having a crosslink network structure. The crosslink network structure is formed by polymerizing a two-functional acryloyl compound having two acryloyl groups with a one-functional acryloyl compound having one acryloyl group.
In this embodiment, the crosslink network structure has a skeleton in which the one-functional acryloyl compound spreads into branches. Since molecular movement of this branched skeleton is active, flexibility is improved.
A second embodiment of the invention provides a solid polymer electrolyte including an ionic salt and a compound able to dissolve the ionic salt and having a crosslink network structure. The crosslink network structure here is formed by polymerizing a two-functional acryloyl compound having two acryloyl groups, the two-functional acryloyl compound is an ester diacrylate or ester dimethacrylate of polyethylene glycol, and the polyethylene glycol is one having a molecular weight ranging from 2,000 to 30,000.
A third embodiment of the invention provides a solid polymer electrolyte including an ionic salt and a compound able to dissolve the ionic salt and having a crosslink network structure. The crosslink network structure here is formed by polymerizing a two-functional acryloyl compound having two acryloyl groups, the two-functional acryloyl compound is ester diacrylate or ester dimethacrylate of copolymer of ethylene oxide and propylene oxide, and the copolymer is one having a molecular weight ranging from 2,000 to 30,000.
The molecular weight of polyethylene glycol or copolymer is limited to within a range of 2,000 to 30,000 in the second and third embodiments, so that the flexibility is improved.
DETAILED DESCRIPTION OF THE INVENTION
In the first embodiment of the invention, the solid polymer electrolyte includes the ionic salt and the compound able to dissolve the ionic salt and has the crosslink network structure. The crosslink network structure is formed by polymerizing the two-functional acryloyl compound having two acryloyl groups with the one-functional acryloyl compound having one acryloyl group.
A primary feature of the first embodiment is the use of the one-functional acryloyl compound having one acryloyl group.
Ester monoacrylate or ester monomethacrylate of polyether without active hydrogen on the end of chain is used for the one-functional acryloyl compound. Further, diethylene glycol, polyethylene glycol, polypropylene glycol, or copolymer of ethylene oxide and propylene oxide, is used for the polyether.
(a) Either ester diacrylate or ester dimethacrylate of polyethylene glycol, or (b) ester diacrylate or ester dimethacrylate of copolymer of ethylene oxide and methylene oxide unit, is used for the two-functional acryloyl compound.
In the above (b), the copolymer may be either a random copolymer or block copolymer. Methylene oxide unit has a mole content of under 30 mole percent incl. is preferably used for the copolymer. This is to keep a balance between a decrease in crystallinity and a solubility of ionic salt. Further, there is preferably used a copolymer having a molecular weight ranging from 2,000 to 30,000, and especially that ranging from 2,000 to 5,000. The reason is as follows. The flexibility, i.e. the mechanical property, is improved when the molecular weight of copolymer is increased. However, when the molecular weight is increased excessively the reactivity is weakened so as to worsen productivity, and the copolymer is liable to crystallize so that the ionic conductivity is lowered. Moreover, when the molecular weight is smaller than 2,000, tensile strength is lessened to induce a problem in practical use.
In the above (a), there is preferably used a copolymer having a molecular weight ranging from 2,000 to 30,000. The reason is same as the case of copolymer (b) described above.
In the second embodiment of the invention, the solid polymer electrolyte includes the ionic salt and the compound able to dissolve the ionic salt and has the crosslink network structure, the crosslink network structure is formed by polymerizing the two-functional acryloyl compound having two acryloyl groups, the two-functional acryloyl compound is ester diacrylate or ester dimethacrylate of polyethylene glycol, and the polyethylene glycol is one having a molecular weight ranging from 2,000 to 30,000.
When the molecular weight of polyethylene glycol ranges from 2,000 to 30,000, a solid polymer electrolyte which is excellent in ionic conductivity, flexibility and tensile strength, can be prepared from the same reason as described above.
In the third embodiment of the invention, the solid polymer electrolyte includes the ionic salt and the compound able to dissolve the ionic salt and has the crosslink network structure, the crosslink network structure is formed by polymerizing two-functional acryloyl compound having two acryloyl groups, the two-functional acryloyl compound is ester diacrylate or ester dimethacrylate of copolymer of ethylene oxide and propylene oxide, and the copolymer is one having a molecular weight ranging from 2,000 to 30,000.
When the molecular weight of copolymer ranges from 2,000 to 30,000, a solid polymer electrolyte which is excellent in ionic conductivity, flexibility and tensile strength, can be prepared from the same reason as described above. The copolymer may be either a random copolymer or block copolymer. Propylene oxide including a mole content of under 30 mole percent incl. is preferably used for the copolymer. This is to keep a balance between a decrease in crystallinity and a solubility of ionic salt.
In all the above embodiments, the polymerization for constructing the crosslink network structure is carried out by heating, irradiation of active light such as ultraviolet light for instance, or irradiation of ionizing radiation such as electron beam.
All the electrolytes of the above embodiments include a compound able to dissolve the ionic salt (abbreviated to "solvent" hereunder). When the solvent is included in the solid polymer electrolyte, the ionic conductivity is improved. In this case, it becomes possible to include a large quantity of solvent when the molecular weight of polyether becomes large. Therefore, the increase of molecular weight is not only effective for the improvement in ionic conductivity but the decrease in strength of crosslink network structure swelled with the solvent.
In all the electrolytes of the above inventions; LiClO 4 , LiBF 4 , LiAsF 6 , LiCF 3 SO 3 , LiPF 6 , LiI, LiBr, LiSCN, NaI, Li 2 B 10 Cl 10 , LiCF 3 CO 2 , NaBr, NaSCN, KSCN, MgCl 2 , Mg(ClO 4 ) 2 , (CH 3 ) 4 , NBF 4 , (CH 3 ) 4 NBr, (C 2 H 5 ) 4 NClO 4 , (C 2 H 5 ) 4 NI, (C 3 H 7 ) 4 NBr, (n-C 4 H 9 ) 4 NClO 4 , (n-C 4 H 9 ) 4 NI and (n-C 5 H 11 ) 4 NI are preferably used for the ionic salt. However, the ionic salt is not limited to these compounds.
As the compound able to dissolve the ionic salt, there are tetrahydrofuran; 2-methyl-tetrahydrofuran; 1,3-dioxoran, 4,4-dimethyl-1,3-dioxane; γ-butyrolactone; ethylene carbonate; propylene carbonate; butylene carbonate; sulfolane; 3-methyl sulfolane tert.-butyl ether; iso-butyl ether; 1,2-dimethoxy ethane; 1,2-ethoxy methoxy ethane; methyl digrime; methyl trigrime; methyl tetragrime; ethyl grime; ethyl digrime or a mixture of them. However, the compound is not limited to these components.
As described above, all of the embodiments can provide the solid polymer electrolytes having good flexibility, i.e. excellent mechanical properties, and high ionic conductivity.
Examples of the inventions will be described hereunder in detail. Examples 1 through 12 relate to the first embodiment, Examples 13 through 17 relate to the second embodiment, and Examples 18 through 22 relate to the third embodiment.
EXAMPLE 1
5 weight parts of ester diacrylate of polyethylene glycol (mean molecular weight: 520), 5 weight parts of ester monomethacrylate of polyethylene glycol (mean molecular weight: 490), 1.3 weight parts of lithium trifluoromethane-sulfolate and 1 weight part of benzophenone were mixed uniformly and dissolved in 10 weight parts of propylene carbonate. The mixture was cast on a glass plate and ultraviolet beam was irradiated on it using a UV lamp of IKW for 10 seconds from a 15 cm distant position, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity of this film was 6.0×10 -4 Scm -1 at a temperature of 25° C. when measured by a complex impedance method.
This film was bent on stainless bars of various diameters, and the resistance to film cracking was evaluated in respect of the diameter of stainless bar. The film cracked when applied on a bar of 3.0 mm diameter.
The film as described below was prepared for comparison. 10 weight parts of ester diacrylate of polyethylene glycol (mean molecular weight: 520), 1.3 weight parts of lithium trifluoromethane-sulfolate and 1 weight part of benzophenone were mixed uniformly and dissolved in 10 weight parts of propylene carbonate. The mixture was cast on a glass plate and ultraviolet beam was irradiated on it in the same way as above, so that a film having a thickness of 100 microns was prepared. The ionic conductivity and strength of this film was measured in the same way. The conductivity was 8.0×10 -4 Scm -1 at a temperature of 25° C. The film cracked when applied on a bar of 5.0 mm diameter.
As described above, the film comprising the solid polymer electrolyte of this example includes good ionic conductivity and has a superior flexibility, i.e. mechanical property.
EXAMPLE 2
5 weight parts of ester dimethacrylate of polyethylene glycol (mean molecular weight: 540), 5 weight parts of ester monoacrylate of polyethylene glycol (mean molecular weight: 470), 1.3 weight parts of lithium trifluoromethane-sulfolate and 1 weight part of benzophenone were mixed uniformly and dissolved in 10 weight parts of propylene carbonate. The mixture was cast on a glass plate and ultraviolet beam was irradiated on it using a UV lamp of 1 KW for 40 seconds from a 15 cm distant position, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity and strength of this film were measured in the same way as in Example 1. The ionic conductivity was 6.0×10 -4 Scm -1 at a temperature of 25° C., and the film cracked when applied on the bar of 3.0 mm diameter.
EXAMPLE 3
A film having a thickness of 100 microns was prepared having the same composition as that of Example 1, other than the following two points: a) benzophenone was not used and b) an electron beam of 2.5 Mrad was used in place of the ultraviolet beam of Example 1.
The ionic conductivity and strength of this film were measured in the same way as in Example 1. The ionic conductivity was 6.0×10 -4 Scm -1 at a temperature of 25° C., and the film cracked when applied on the bar of 3.0 mm diameter.
EXAMPLE 4
A liquid which included 100 weight parts of methylethylketone mixed with 9.5 weight parts of lithium perchlorate, was added and mixed to a liquid which comprised 70 weight parts of a random copolymer of ester dimethacrylate (including 20 mole percent of methylene oxide, molecular weight: 4,000) of ethylene oxide and methylene oxide unit added to and mixed uniformly with 30 weight parts of ester monomethacrylate (molecular weight: 400) of methoxylation polyethylene glycol. This mixed liquid was cast on a glass plate and the methyl-ethyl-ketone was evaporated. Then, 6 Mrad electron beam was irradiated on it to stiffen and prepare a film having a thickness of 100 microns.
The ionic conductivity of this film was 1×10 -5 Scm -1 at a temperature of 25° C. when measured by the complex impedance method.
90° bending test and 180° bending test were carried out in order to examine the flexibility. This film did not crack in either of the tests.
Several films having a thickness of 100 microns were prepared in the same way, using the foregoing random copolymers (including 20 mole percent of methylene oxide) having molecular weights of 400, 1,000, 2,000 and 10,000, respectively.
Ionic conductivities and results of bending tests of the prepared films are listed in Table 1.
TABLE 1______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 1 × 10.sup.-6 Cracked Cracked1,000 1 × 10.sup.-5 Cracked Cracked2,000 2 × 10.sup.-5 Not cracked Not cracked4,000 1 × 10.sup.-5 Not cracked Not cracked10,000 8 × 10.sup.-6 Not cracked Not cracked______________________________________
It can be understood from Table 1 that the flexibility is improved as the molecular weight of copolymer increases.
EXAMPLE 5
Propylene carbonate was used in place of the methyl-ethyl-ketone of Example 4. This propylene carbonate was left in the film without being evaporated, so that a film having a thickness of 100 microns was prepared in the same way as Example 4 other than the above details.
Ionic conductivities and results of bending tests of prepared films are listed in Table 2.
TABLE 2______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 2 × 10.sup.-4 Cracked Cracked1,000 2 × 10.sup.-4 Cracked Cracked2,000 3 × 10.sup.-4 Not cracked Not cracked4,000 5 × 10.sup.-4 Not cracked Not cracked10,000 1 × 10.sup.-3 Not cracked Not cracked______________________________________
EXAMPLE 6
A random copolymer having a molecular weight of 4,000 was used, in which the ester dimethacrylate of Example 5 was replaced by ester diacrylate. A film having a thickness of 100 microns was prepared in the same way as Example 5 other than the above detail.
The ionic conductivity of this film was 4.5×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, the film did not crack in both the 90° bending test and 180° bending test.
EXAMPLE 7
100 weight parts of propylene carbonate solution including 11.5 weight percent of LiCF 3 SO 3 were added to and mixed uniformly with a liquid composed of 50 weight parts of ester diacrylate (molecular weight: 4,000) of polyethylene glycol mixed with 50 weight parts of ester monoacrylate of methoxylation deithylene glycol. This mixture was cast on a glass plate and was irradiated by an electron beam of 6 Mrad, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity of this film was 3×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
Several films having a thickness of 100 microns were prepared in the same way by using ester diacrylate of polyethylene glycols having molecular weights of 400, 1,000, 2,000 and 10,000, respectively.
Ionic conductivities and results of bending tests of prepared films are listed in Table 3.
TABLE 3______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 1 × 10.sup.-4 Cracked Cracked1,000 1 × 10.sup.-4 Cracked Cracked2,000 2 × 10.sup.-4 Not cracked Cracked4,000 3 × 10.sup.-4 Not cracked Not cracked______________________________________
EXAMPLE 8
Dimethoxy ethane was used in place of the propylene carbonate of Example 7. The dimethoxy ethane was cast on a glass plate and then evaporated, so that a film having a thickness of 100 microns was prepared in the same way as the Example 7 other than the above detail. The molecular weight of the ester diacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 7×10 -6 SCM -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° C. bending test.
Several films having a thickness of 100 microns were prepared in the same way by using ester diacrylate of polyethylene glycols having molecular weights of 400, 1,000, 2,000 and 10,000, respectively.
Ionic conductivities and results of bending tests of prepared films are listed in Table 4.
TABLE 4______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 3 × 10.sup.-6 Cracked Cracked1,000 2 × 10.sup.-5 Cracked Cracked2,000 3 × 10.sup.-5 Not cracked Cracked4,000 7 × 10.sup.-6 Not cracked Not cracked10,000 5 × 10.sup.-6 Not cracked Not cracked______________________________________
EXAMPLE 9
In place of the electron beam radiation of Example 8, 5 weight parts of azobis isobutyro nitrile were added to the solution of Example 8 and it reacted at a temperature of 80° C. for one hour. A film having a thickness of 100 microns was prepared in the same way as Example 8 other than this detail. The molecular weight of the used ester diacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 7×10 -6 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
EXAMPLE 10
In place of the electron beam radiation of Example 8, 2 weight parts of benzophenone and 2 weight parts of triethylamine were added to the Example 8 solution, and ultraviolet beam was irradiated on it using a mercury lamp of 1 KW for 30 seconds from a 15 cm distant position. A film having a thickness of 100 microns was prepared in the same way as Example 8 other than these details. The molecular weight of the ester diacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 7×10 -6 Scm 31 1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
EXAMPLE 11
Ester diamethaorylate (molecular weight: 4,000) of polyethylene glycol was used in place of the ester diacrylate of polyethylene glycol of Example 7, so that a film having a thickness of 100 microns was prepared in the same way as in Example 7 other than this point.
The ionic conductivity of this film was 5×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, the film did not crack even in the 180° bending test.
EXAMPLE 12
100 weight parts of propylene carbonate solution including 11.5 weight percent of LiCF 3 SO 3 were added to and mixed uniformly with a liquid made by mixing 50 weight parts of ester dimethacrylate (molecular weight: 4,000) of polyethylene glycol with 50 weight parts of copolymer (including 20 mole percent of propylene oxide, molecular weight: 400) of monomethoxylation ethylene oxide and propylene oxide. This mixed liquid was cast on a glass plate and electron beam of 6 Mrad was irradiated on it, so that a film having a thickness of100 microns was prepared.
The ionic conductivity of this film was 6×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
EXAMPLE 13
100 weight parts of propylene carbonate solution including 11.5 weight percent of LiCF 3 SO 3 were added to and mixed uniformly with 100 weight parts of ester dimethacrylate (molecular weight: 4,000) of polyethylene glycol. This mixed liquid was cast on a glass plate and electron beam of 10 Mrad was irradiated on it, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity of this film was 3×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack in the 90° bending test.
Several films having a thickness of 100 microns were prepared in the same way by using ester dimethaorylate of polyethylene glycols having molecular weights of 400, 1,000, 2,000 and 10,000, respectively.
Ionic conductivities and results of bending tests of prepared films are listed in Table 5.
TABLE 5______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 1 × 10.sup.-4 Cracked Cracked1,000 1 × 10.sup.-4 Cracked Cracked2,000 2 × 10.sup.-4 Not cracked Cracked4,000 3 × 10.sup.-4 Not cracked Cracked10,000 4 × 10.sup.-4 Not cracked Not cracked______________________________________
EXAMPLE 14
Dimethoxy-ethane was in place of the propylene carbonate of Example 13. The dimethoxy-ethane solution was cast on a glass plate and then evaporated, so that a film having a thickness of 100 microns was prepared in the same way as in Example 14 other than this detail. The molecular weight of the used ester dimethacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 3×10 -6 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack in the 90° bending test.
Several films having a thickness of 100 microns were prepared in the same way by using ester dimethacrylate of polyethylene glycols having molecular weights of 400, 1,000, 2,000, and 10,000, respectively.
Ionic conductivities and results of bending tests of prepared films are listed in Table 6.
TABLE 6______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 400 1 × 10.sup.-6 Cracked Cracked1,000 1 × 10.sup.-5 Cracked Cracked2,000 8 × 10.sup.-5 Not cracked Cracked4,000 3 × 10.sup.-6 Not cracked Cracked10,000 1 × 10.sup.-6 Not cracked Not cracked______________________________________
EXAMPLE 15
In place of the electron beam radiation of Example 14, 5 weight parts of azobis isobutyro nitrile were added to the solution of Example 14 and it reacted at a temperature of 80° C. for one hour. A film having a thickness of 100 microns was prepared in the same way as Example 14 other than this detail. The molecular weight of the used ester dimethacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 3×10 -6 Scm -1 a a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack in the 90° bending test.
EXAMPLE 16
In place of the electron beam radiation of Example 14, 2 weight parts of benzophenone and 2 weight parts of triethylamine were added to the Example 14 solution, and ultraviolet beam was irradiated on it using a mercury lamp of 1 KW for 30 seconds from a 15 cm distant position. A film having a thickness of 100 microns was prepared in the same way as Example 14 other than these details. The molecular weight of the ester dimethacrylate of polyethylene glycol was 4,000.
The ionic conductivity of this film was 3×10 -6 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack in the 90° bending test.
EXAMPLE 17
Ester diacrylate (molecular weight: 4,000) was used in place of the ester dimethacrylate of Example 13. A film having a thickness of 100 microns was prepared in the same way as Example 13 other than this point.
The ionic conductivity of this film was 2×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, the film did not crack in the 90° bending test.
EXAMPLE 18
A liquid including 9.5 weight parts of lithium perchlorate mixed with 100 weight parts of dimethoxyethane, was added to 100 weight parts of a ester dimethacrylate copolymer (including 20 mole percent of propylene oxide, molecular weight: 4,200) of ethylene oxide and propylene oxide. 2 weight parts of benzophenone and 2 weight parts of triethylamine were added to and mixed with the above liquid. The mixed liquid was cast on a glass plate and the dimethoxyethane was evaporated. Then, ultraviolet beam was irradiated on it using an ultraviolet lamp of 1 KW for 30 seconds from a 15 cm distance position in an argon atmosphere, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity of this film was 6×10 -6 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
Several films having a thickness of 100 microns were prepared in the same way by using ester dimethacrylate of copolymers (including 20 moles percent of propylene oxide) of ethylene oxide and propylene oxide having molecular weights of 450, 1,100, 2,100 and 10,000, respectively.
Ionic conductivities and results of bending tests of prepared films are listed in Table 7.
TABLE 7______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 450 5 × 10.sup.-6 Cracked Cracked1,100 1 × 10.sup.-5 Cracked Cracked2,100 8 × 10.sup.-5 Not cracked Cracked4,200 6 × 10.sup.-6 Not cracked Not cracked10,000 3 × 10.sup.-6 Not cracked Not cracked______________________________________
EXAMPLE 19
5 weight parts of azobis isobutyro nitrile were used in place of 2 weight parts of benzophenone and heated at a temperature of 80° C. for one hour in place of the ultraviolet beam radiation of Example 18. A film having a thickness of 100 microns were prepared in the same way as in Example 18 other than these details.
The ionic conductivity of this film was 6×10 -6 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for flexibility, this film did not crack even in the 180° bending test.
EXAMPLE 20
A liquid made of 9.5 weight parts of lithium perchlorate mixed with 100 weight parts of propylene carbonate, was added to 100 weight parts of an ester dimethacrylate copolymer (including 20 mole percent of propylene oxide, molecular weight: 4,200) of ethylene oxide and propylene oxide. 2 weight parts of benzophenone were added to and mixed with the above liquid. The mixed liquid was cast on a glass plate. Then, ultraviolet beam was irradiated on it using an ultraviolet lamp of 1 KW for 30 second from a 15 cm distance position in an argon atmosphere, so that a film having a thickness of 100 microns was prepared.
Several films having a thickness of 100 microns were prepared in the same way by using ester dimethacrylate of copolymers (including 20 mole percent of propylene oxide) of ethylene oxide and propylene oxide having molecular weights of 450, 1,100, 2,100 and 10,000, respectively.
Ionic conductivities and results of being tests of prepared films are listed in Table 8.
TABLE 8______________________________________ Ionic 90° 180°Molecular conductivity bending bendingweight (Scm.sup.-1) test test______________________________________ 450 1 × 10.sup.-4 Cracked Cracked1,100 1 × 10.sup.-4 Cracked Cracked2,100 2 × 10.sup.-4 Not cracked Cracked4,200 3 × 10.sup.-4 Not cracked Not cracked10,000 4 × 10.sup.-4 Not cracked Not cracked______________________________________
EXAMPLE 21
The same composition as in Example 20 was used other than that the benzophenone was not used. An electron beam of 10 Mrad was used instead of the ultraviolet radiation of Example 20, so that a film having a thickness of 100 microns was prepared. The molecular weight of the copolymer of ethylene oxide and propylene oxide was 4,200.
The ionic conductivity of this film was 2×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test.
EXAMPLE 22
A liquid, made of 9.5 weight parts of lithium perchlorate mixed with 100 weight parts of propylene carbonate, was added to 100 weight parts of an ester diacrylate copolymer (including 20 mole percent of propylene oxide, molecular weight: 4,200) of ethylene oxide and propylene oxide. The mixed liquid was cast on a glass plate. Then, an electron beam of 5 Mrad was irradiated on it in an argon atmosphere, so that a film having a thickness of 100 microns was prepared.
The ionic conductivity of this film was 2×10 -4 Scm -1 at a temperature of 25° C. when measured by the complex impedance method. As for the flexibility, this film did not crack even in the 180° bending test. | A primary invention is a solid polymer electrolyte including an ionic salt and a compound able to dissolve the ionic salt and having a crosslink network structure. A crosslink network structure is formed by polymerizing a two-functional acryloyl compound having two acryloyl groups with a one-functional acryloyl compound having one acryloyl group. In this solid polymer electrolyte, the crosslink network structure has a skeleton in which the one-functional acryloyl compound spreads into branches. Since molecular movement of this branched skeleton is active, its flexibility is improved. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to a radiographic image capturing system (radiographic imaging system) and a radiographic image capturing method (radiographic imaging method) for applying radiation to a subject and converting radiation that has passed through the subject into a radiographic image with a radiation detecting device. The present invention also concerns a radiographic image acquiring apparatus (radiograph acquisition device) for acquiring a radiographic image from a radiation detecting device.
BACKGROUND ART
[0002] In the medical field, it has widely been customary to apply radiation to a subject, to convert radiation that has passed through the subject into a radiographic image with a radiation conversion panel, and to acquire the radiographic image from the radiation conversion panel. One known form of radiation conversion panel is a stimulable phosphor panel for storing radiation energy representing a radiographic image in a phosphor, and retrieving the radiographic image as stimulated light emitted in response to application of stimulating light thereto. The stimulable phosphor panel is supplied to a radiographic image acquiring apparatus, which performs a process of acquiring the radiographic image in order to obtain the radiographic image as a visible image.
[0003] In operating rooms or the like, it is necessary to immediately read radiographic images from radiation conversion panels, which have captured the radiographic images, and to display the radiographic images in order to treat subjects (patients) quickly and properly. Radiation conversion panels that have been developed to meet such requirements include a direct-conversion-type radiation detector, which employs a solid-state detector for converting radiation directly into electric signals, and an indirect-conversion-type radiation detector, which employs a scintillator for converting radiation into visible light and a solid-state detector for converting the visible light into electric signals.
[0004] Certain medical organizations incorporate a radiographic image capturing system having a plurality of radiation detecting devices with radiation conversion panels employed therein (see Japanese Laid-Open Patent Publication No. 2004-073462 and Japanese Laid-Open Patent Publication No. 2009-219586).
[0005] It may be assumed that all of the radiation detecting devices of such a radiographic image capturing system include therein direct-conversion-type or indirect-conversion-type radiation conversion panels (hereinafter referred to as “FPDs” (Flat Panel Detectors)). A process of applying radiation to a subject and acquiring a radiographic image of the subject from such radiation conversion panels will be described below.
[0006] First, a doctor or radiological technician selects one of the radiation detecting devices, and makes the FPD of the selected radiation detecting device ready to store electric signals (electric charges) converted from the radiation.
[0007] Then, the doctor or radiological technician places a subject (patient) between a radiation source and the selected radiation detecting device. When the radiation source applies radiation through the subject to the radiation detecting device, the FPD converts radiation that has passed through the subject into electric charges and stores the electric charges. After radiation has been applied to the radiation detecting device, the radiographic image acquiring apparatus acquires the electric charges stored in the FPD as a radiographic image representative of the subject.
SUMMARY OF INVENTION
[0008] With the radiographic image capturing system according to the background art, as described above, one radiation detecting device is selected, radiation is applied from the radiation source through the subject to the selected radiation detecting device, and the radiographic image acquiring apparatus acquires a radiographic image from the selected radiation detecting device. In this manner, the subject and the radiographic image are associated with each other.
[0009] If the selected radiation detecting device is in a certain state (e.g., if the selected radiation detecting device fails, or if the amount of electric power charged in a battery thereof is insufficient to capture a radiographic image, or if the selected radiation detecting device is physically spaced from the subject (in terms of distances, angles, and positions in relation to an image capturing base used in combination therewith) such that the selected radiation detecting device cannot be used, then the selected radiation detecting device is replaced with another radiation detecting device. If radiation is applied from the radiation source through the subject to the other radiation detecting device, the radiographic image generated by the other radiation detecting device is representative of the subject.
[0010] However, if the doctor or radiological technician forgets to indicate to the radiographic image acquiring apparatus that the radiation detecting devices have been changed in order to capture the radiographic image, then the radiographic image acquiring apparatus is likely to acquire the radiographic image from the selected radiation detecting device, and to associate the subject and the acquired radiographic image with each other. As a result, in a case that the radiographic image acquiring apparatus acquires the radiographic image from the selected radiation detecting device, since the acquired radiographic image does not represent the subject, the radiographic image acquiring apparatus judges the image capturing process as a failure, and indicates that a process for capturing a radiographic image of the subject should be applied again.
[0011] Stated otherwise, if a radiation detecting device (another radiation detecting device) having an FPD that is actually irradiated with radiation, and a radiation detecting device (a selected radiation detecting device) having an FPD from which the radiographic image is acquired are not the same as each other, then the radiographic image capturing system according to the background art does not acquire a radiographic image representative of the subject from the other radiation detecting device, but rather, performs another process for capturing a radiographic image of the subject again. Consequently, the radiographic image capturing system tends to expose the subject to radiation unnecessarily.
[0012] The present invention has been made in order to eliminate the above difficulties. It is an object of the present invention to provide a radiographic image acquiring apparatus, a radiographic image capturing system, and a radiographic image capturing method, which are capable of reliably acquiring a radiographic image representative of a subject while preventing the subject from being needlessly exposed to radiation.
[0013] A radiographic image acquiring apparatus according to the present invention comprises a selector for selecting one of a plurality of radiation detecting devices, each of which is capable of converting radiation into a radiographic image, and an acquirer for acquiring a radiographic image from the one radiation detecting device and a radiographic image from at least one other radiation detecting device that differs from the one radiation detecting device, from among the plurality of radiation detecting devices, in a case that a subject is irradiated with radiation.
[0014] A radiographic image capturing system according to the present invention comprises a plurality of radiographic image capturing apparatus including respective radiation sources each of which outputs radiation, and respective radiation detecting devices each of which converts the radiation into a radiographic image, and a radiographic image acquiring apparatus including a selector for selecting the radiation detecting device of one radiographic image capturing apparatus from among the radiation detecting devices of the plurality of radiographic image capturing apparatus, and an acquirer for acquiring a radiographic image from the one radiation detecting device and a radiographic image from at least one other radiation detecting device that differs from the one radiation detecting device, from among the radiation detecting devices of the plurality of radiographic image capturing apparatus, in a case that a subject is irradiated with radiation.
[0015] A method of capturing a radiographic image according to the present invention comprises the steps of selecting, with a selector, one of a plurality of radiation detecting devices, each of which is capable of converting radiation into a radiographic image, applying radiation to the subject, and acquiring, with an acquirer, a radiographic image from the one radiation detecting device and a radiographic image from at least one other radiation detecting device that differs from the one radiation detecting device, from among the plurality of radiation detecting devices.
[0016] According to the above invention, the acquirer acquires both a radiographic image from the one radiation detecting device selected by the selector, and a radiographic image from at least one other radiation detecting device that differs from the one radiation detecting device.
[0017] If radiation is applied through the subject to the one radiation detecting device, then the control device acquires a radiographic image from the one radiation detecting device, thereby acquiring a radiographic image representative of the subject. If radiation is applied through the subject to the other radiation detecting device, then the control device acquires a radiographic image from the other radiation detecting device, thereby acquiring a radiographic image representative of the subject.
[0018] More specifically, in a case that the one image capturing apparatus is changed over to the other image capturing apparatus in order to capture a radiographic image, it is desirable for the selector to select the other image capturing apparatus before the radiographic image has been captured. However, the other image capturing apparatus may not be selected for capturing a radiographic image, and hence, a radiographic image may not be acquired from the other image capturing apparatus. According to the present embodiment, regardless of whether or not the selector has selected the other image capturing apparatus, both a radiographic image from the one radiation detecting device and a radiographic image from the other radiation detecting device are acquired, thereby reliably acquiring a radiographic image representative of the subject.
[0019] According to the present embodiment, therefore, regardless of whether the one radiation detecting device or the other radiation detecting device is used to capture a radiographic image, the acquirer reliably acquires a radiographic image representative of the subject. As a result, the subject is prevented from being exposed to radiation unnecessarily.
[0020] The radiographic image acquiring apparatus may further comprise a judging section for judging whether or not the radiographic image from the one radiation detecting device is a significant radiographic image representative of the subject.
[0021] Therefore, it is possible to determine whether or not the radiographic image from the one radiation detecting device is a significant radiographic image representative of the subject. A significant radiographic image, which is representative of the subject, is a radiographic image represented by digital image data, an average luminance value or a variance luminance value of which is equal to or greater than a prescribed threshold value, for example.
[0022] The radiographic image acquiring apparatus may further comprise an indicating unit for externally indicating a judgment result from the judging section, if the judging section judges that the radiographic image from the one radiation detecting device is not the significant radiographic image.
[0023] Therefore, the doctor or radiological technician can easily recognize that an image capturing process has been carried out without requiring the selector to select the other radiation detecting device.
[0024] The judging section judges whether or not the radiographic image from the other radiation detecting device is the significant radiographic image, if the judging section judges that the radiographic image from the one radiation detecting device is not the significant radiographic image, thereby determining whether or not the radiographic image from the other radiation detecting device is the significant radiographic image.
[0025] The acquirer successively acquires radiographic images from other radiation detecting devices until the judging section has found the significant radiographic image, if the judging section judges that the radiographic image from the one radiation detecting device is not the significant radiographic image.
[0026] The selector selects the one radiation detecting device and designates an imaging method to be carried out upon application of radiation to the subject using the one radiation detecting device, and the acquirer acquires a radiographic image preferentially from a radiation detecting device, from among the other radiation detecting devices, which produces a radiographic image according to the imaging method, or acquires a radiographic image preferentially from another radiation detecting device that is in close proximity to the one radiation detecting device.
[0027] If the one radiation detecting device is not used, but rather another radiation detecting device is used to capture a radiographic image, then it is assumed it is highly likely to have captured a radiographic image using another radiation detecting device, according to the same imaging method as the imaging method (e.g., an upright imaging process or a supine imaging process) of the one radiation detecting device, or to have captured a radiographic image using another radiation detecting device that is closest in proximity to the one radiation detecting device. It is thus possible to acquire a radiographic image preferentially from another radiation detecting device according to the same imaging method, or from another radiation detecting device that is closest in proximity to the one radiation detecting device, thereby making it possible to acquire a significant radiographic image quickly and reliably.
[0028] The radiographic image acquiring apparatus may further comprise a switcher for switching selection of the one radiation detecting device to selection of the other radiation detecting device, if the judging section judges that the radiographic image from the other radiation detecting device is the significant radiographic image.
[0029] Since a next imaging cycle may be carried out using the other radiation detecting device, which has produced a significant radiographic image, the switcher automatically switches from selection of the one radiation detecting device to selection of the other radiation detecting device, thereby preventing the other radiation detecting device from being unselected due to an oversight in a subsequent image capturing cycle.
[0030] The radiographic image acquiring apparatus preferably further comprises an output unit for externally outputting the radiographic image, which the judging section has judged as being the significant radiographic image.
[0031] The doctor can thus interpret a significant radiographic image for facilitating diagnosis.
[0032] In a case that radiation is applied to the subject in an image capturing chamber, the acquirer acquires the radiographic image from the one radiation detecting device and the radiographic image from the other radiation detecting device, which also is present in the image capturing chamber, from among the plurality of radiation detecting devices.
[0033] Inasmuch as a radiographic image is acquired from the radiation detecting device that is present in the image capturing chamber, it is possible to reliably prevent image acquiring processes from being performed needlessly on radiation detecting devices that are present outside of the image capturing chamber, while also efficiently carrying out a process of acquiring radiographic images.
[0034] The radiographic image acquiring apparatus further comprises an identification information storage unit for storing identification information of the plurality of radiation detecting devices that are present in an image capturing chamber in a case that radiation is applied to the subject in the image capturing chamber, wherein the acquirer acquires radiographic images from the plurality of radiation detecting devices that are present in the image capturing chamber based on the identification information stored in the identification information storage unit.
[0035] Inasmuch as radiographic images are acquired only from radiation detecting devices that are present in the image capturing chamber, it is possible to reliably prevent image acquiring processes from being performed in error on radiation detecting devices that are present outside of the image capturing chamber, while also efficiently carrying out the process of acquiring radiographic images.
[0036] Preferably, each of the radiation detecting devices comprises a radiation conversion panel for converting radiation into electric charges, storing the electric charges, and outputting the stored electric charges as an electric signal to an external device. The radiation conversion panel is made ready to store electric charges before radiation is applied to the subject.
[0037] It is not necessary to irradiate the radiation detecting devices with triggering radiation in order to instruct the radiation conversion panel to store electric charges prior to a main image capturing process. Therefore, the arrangement for instructing the storage of electric charges is simplified, and the dose of radiation to which the subject is exposed can be reduced.
[0038] According to the present invention, regardless of whether the one radiation detecting device or the other radiation detecting device is used to capture a radiographic image, the acquirer reliably acquires a radiographic image representative of the subject. As a result, the subject is prevented from being exposed to radiation needlessly.
BRIEF DESCRIPTION OF DRAWINGS
[0039] FIG. 1 is a block diagram of a radiographic image capturing system according to an embodiment of the present invention;
[0040] FIG. 2 is a schematic view of a radiation detecting device;
[0041] FIG. 3 is a circuit diagram of the radiation detecting device shown in FIG. 2 ;
[0042] FIG. 4 is a detailed block diagram of the radiographic image capturing system shown in FIG. 1 ;
[0043] FIG. 5 is a flowchart of an operation sequence of the radiographic image capturing system according to the embodiment; and
[0044] FIG. 6 is a timing chart showing an elapse of time from turning on of an exposure switch to completion of acquisition of a radiographic image.
DESCRIPTION OF EMBODIMENTS
[0045] A radiographic image capturing system incorporating a radiographic image acquiring apparatus according to an embodiment of the present invention will be described below with reference to FIGS. 1 through 6 , in relation to a radiographic image capturing method carried out by the radiographic image capturing system.
[0046] As shown in FIG. 1 , a radiographic image capturing system 10 according to the present embodiment includes a medical information system 12 (HIS: Hospital Information System) for managing medical procedures in a hospital, a radiological information system 14 (RIS) for managing a process of capturing radiographic images in a radiological department, a viewer 16 which a doctor uses to make a diagnosis based on the interpretation of radiographic images, and consoles 24 , 26 , 28 disposed in respective processing chambers, which are located respectively adjacent to a plurality of image capturing chambers 18 , 20 , 22 of the radiological department, for managing and controlling respective image capturing apparatus 44 , 46 , 48 having different specifications. The HIS 12 , the RIS 14 , the viewer 16 , and the consoles 24 , 26 , 28 are interconnected via an in-hospital network 30 . In the processing chambers, respective cradles 32 , 34 , 36 are disposed for charging radiation detecting devices 52 , 62 , 72 connected respectively to the consoles 24 , 26 , 28 .
[0047] The image capturing chamber 18 houses therein image capturing apparatus 44 , 46 for capturing images of subjects 42 in a supine position (supine imaging process), an image capturing apparatus 48 for capturing an image of a subject 42 in an upright position (upright imaging process), and a control device (acquirer) 40 interconnecting the console 24 and the image capturing apparatus 44 , 46 , 48 . Each of the other image capturing chambers 20 , 22 also houses therein the control device 40 and the image capturing apparatus 44 , 46 , 48 , although such devices have been omitted from illustration in FIG. 1 . The consoles 24 , 26 , 28 and the corresponding control devices 40 jointly make up a radiographic image acquiring apparatus according to the present embodiment.
[0048] The image capturing apparatus 44 has an image capturing base 50 and a radiation detecting device 52 placed on the image capturing base 50 . The image capturing apparatus 46 has an image capturing base 60 and a radiation detecting device 62 placed in the image capturing base 60 . The image capturing apparatus 48 has an upright image capturing base 70 and a radiation detecting device 72 placed in the image capturing base 70 . The image capturing apparatus 44 , 46 , 48 share a single radiation source 54 . When the radiation source 54 applies radiation 56 to the subject 42 , the irradiated radiation detecting device converts the radiation 56 , which has passed through the subject 42 , into a radiographic image representative of the subject 42 , whereas the other two radiation detecting devices produce radiographic images that are not representative of the subject 42 .
[0049] In the image capturing apparatus 44 , the radiation detecting device 52 is not housed in the image capturing base 50 . The image capturing apparatus 44 is not limited to performing the supine imaging process illustrated in FIG. 1 , but may also capture an image of a desired region (legs or the like) of the subject 42 while the subject 42 sits on the image capturing base 50 , for example. In FIG. 1 , the control device 40 and the image capturing apparatus 44 , 46 , 48 are illustrated as being interconnected by wired links. However, the control device 40 and the image capturing apparatus 44 , 46 , 48 may be interconnected via wireless links. In FIG. 1 , the radiation detecting devices 52 , 62 , 72 are disposed respectively in the image capturing apparatus 44 , 46 , 48 . According to the present embodiment, however, at least two radiation detecting devices may be disposed in the image capturing apparatus 44 , 46 , 48 . In such a case, one of the three image capturing apparatus 44 , 46 , 48 , which is free of a radiation detecting device, may utilize the radiation detecting device of one of the other image capturing apparatus.
[0050] As shown in FIG. 2 , each of the radiation detecting devices 52 , 62 , 72 employed by the image capturing apparatus 44 , 46 , 48 has a casing 80 made of a material that is permeable to radiation 56 . The casing 80 houses therein a grid 82 for removing scattered rays of radiation 56 from the subject 42 (see FIG. 1 ), a radiation conversion panel 84 for converting radiation 56 that has passed through the subject 42 into electric image information, and a lead plate 86 for absorbing back scattered rays of radiation 56 . The grid 82 , the radiation conversion panel 84 , and the lead plate 86 are successively arranged from an irradiated surface of the casing 80 toward a bottom surface of the casing 80 . The irradiated surface of the casing 80 may be constructed as the grid 82 .
[0051] The radiation conversion panel 84 , which is in the form of a planar radiation detector (FPD), comprises a direct-conversion-type radiation detector for detecting and converting radiation 56 directly into electric charges and storing the electric charges, or an indirect-conversion-type radiation detector for converting radiation 56 into visible light, converting the visible light into electric charges, and storing the electric charges. It is assumed hereinafter that the radiation conversion panel 84 comprises an indirect-conversion-type radiation detector.
[0052] The casing 80 also houses therein a battery 88 , which serves as a power supply for the radiation conversion panel 84 , a controller 90 for energizing the radiation conversion panel 84 with electric power supplied from the battery 88 , and a transceiver 92 for sending a radiographic image of the subject 42 , which is represented by electric charges stored in the radiation conversion panel 84 , via the control device 40 (see FIG. 1 ) to the consoles 24 , 26 , 28 . The casing 80 has on a side thereof a power supply switch 94 for activating the radiation detecting device 52 , 62 , 72 .
[0053] A circuit arrangement inside the radiation detecting device 52 , 62 , 72 will be described below with reference to FIG. 3 .
[0054] The radiation conversion panel 84 comprises an array of TFTs 106 arranged in rows and columns, and a photoelectric conversion layer 101 made of a material such as amorphous silicon (a-Si) or the like, and having solid-state detectors (hereinafter referred to as pixels) 100 provided thereon for converting visible light into electric signals, the photoelectric conversion layer 101 being disposed on the array of TFTs 106 . The pixels 100 , which are supplied with a bias voltage Vb from the battery 88 , store electric charges generated by conversion of visible light into electric signals (analog signals). The TFTs 106 are turned on along each row at a time to read the electric charges as an image signal.
[0055] The TFTs 106 connected to the respective pixels 100 are connected to respective gate lines 102 that extend parallel to the rows, and to respective signal lines 104 that extend parallel to the columns. The gate lines 102 are connected to a line scanning driver 108 , and the signal lines 104 are connected to a multiplexer 110 . The gate lines 102 are supplied with control signals Von, Voff for turning on and off the TFTs 106 along the rows from the line scanning driver 108 . The line scanning driver 108 comprises a plurality of first switches SW 1 for switching between the gate lines 102 , and an address decoder 112 for outputting a selection signal for selecting one of the first switches SW 1 at a time. The address decoder 112 is supplied with an address signal from the controller 90 .
[0056] The signal lines 104 are supplied with electric charges stored in the pixels 100 through the TFTs 106 arranged in the columns. The electric charges supplied to the signal lines 104 are amplified by amplifiers 114 . The amplifiers 114 are connected through respective sample and hold circuits 116 to the multiplexer 110 . The multiplexer 110 comprises a plurality of second switches SW 2 for successively switching between the signal lines 104 , and an address decoder 118 for outputting a selection signal for selecting one of the second switches SW 2 at a time. The address decoder 118 is supplied with an address signal from the controller 90 . The multiplexer 110 is connected to an A/D converter 120 . A radiographic image signal is converted by the A/D converter 120 into a digital image signal, which is supplied to the controller 90 . The controller 90 stores the radiographic image signal as a digital image signal in an image memory 130 , or alternatively, sends the radiographic image signal stored in the image memory 130 through the transceiver 92 to the control device 40 .
[0057] The TFTs 106 , which function as switching elements, may be combined with any of various other image capturing devices such as a CMOS (Complementary Metal-Oxide Semiconductor) image sensor, or may be replaced with a CCD (Charge-Coupled Device) image sensor, in which electric charges are shifted and transferred by shift pulses that correspond to gate signals used in the TFTs 106 .
[0058] FIG. 4 is a detailed block diagram of the radiographic image capturing system 10 . Components of the radiographic image capturing system 10 , which have not been described with reference to FIGS. 1 through 3 , will primarily be described below.
[0059] Each of the radiation detecting devices 52 , 62 , 72 has an ID memory 132 storing therein ID information for identifying a particular radiation detecting device. The controller 90 performs a calibration process (a process of correcting brightness, darkness, and defects in the radiographic images) on the radiation conversion panel 84 , either periodically or upon activation of the radiation detecting devices 52 , 62 , 72 , and stores various tables generated by the calibration process for brightness, darkness, and defect correction in the image memory 130 . The calibration process that is carried out is a known process (see, for example, Japanese Laid-Open Patent Publication No. 2009-028373).
[0060] The radiation source 54 has a controller 134 for controlling the radiation source 54 to emit radiation 56 , and a transceiver 136 for sending signals to and receiving signals from the control device 40 .
[0061] The control device 40 has a memory 138 for storing the various tables referred to above, and a transceiver 140 for sending signals to and receiving signals from the transceivers 92 of the radiation detecting devices 52 , 62 , 72 , the transceiver 136 of the radiation source 54 , and the consoles 24 , 26 , 28 . The transceiver 140 sends radiation image signals acquired from the image memory 130 via the controller 90 and the transceiver 92 to the consoles 24 , 26 , 28 .
[0062] Each of the consoles 24 , 26 , 28 has a controller 142 , a transceiver 144 , an ID memory (identification information storage unit) 146 , an order information storage unit 148 , an image capturing condition setting section 150 , an image processor 152 , an image memory 154 , a display unit (output unit, indicating unit) 156 , an image judging section (judging section, switcher) 157 , a speaker (indicating unit) 158 , an operating unit (selector, switcher) 159 , and an exposure switch 160 .
[0063] The transceiver 144 sends signals to and receives signals from the HIS 12 , the RIS 14 , the viewer 16 , and the other consoles via the in-hospital network 30 , and also sends signals to and receives signals from the control device 40 and the cradles 32 , 34 , 36 .
[0064] The controllers 142 of the consoles 24 , 26 , 28 control components in each of the respective consoles 24 , 26 , 28 .
[0065] Each of the controllers 142 stores image capturing order information acquired from the RIS 14 in the order information storage unit 148 . The controller 142 also stores image capturing conditions for the image capturing apparatus 44 , 46 , 48 , which have been acquired from the RIS 14 , or which have been set by the doctor or radiological technician by operating the operating unit 159 such as a keyboard, a mouse, or the like, in the image capturing condition setting section 150 .
[0066] The order information is generated by the doctor using the RIS 14 . The order information includes patient information for identifying the patient, such as the name, age, gender, etc., of the patient, an image capturing apparatus to be used to capture a radiographic image, a body region to be imaged, an imaging method such as a supine imaging process or an upright imaging process, and image capturing conditions. The image capturing conditions refer to conditions for determining a dose of radiation to be applied to the subject 42 , e.g., a tube voltage and a tube current of the radiation source 54 , an irradiation time of the radiation 56 , etc.
[0067] The doctor or radiological technician operates the operating unit 159 in order to select one of the three image capturing apparatus 44 , 46 , 48 , which are present in the respective image capturing chambers 18 , 20 , 22 , as an image capturing apparatus to be used to capture radiographic images, as well as to select an imaging method for the selected image capturing apparatus, and to enter the ID information (identification information) of a radiation detecting device (one radiation detecting device) to be used by the selected image capturing apparatus. The controller 142 sets the selected image capturing apparatus and the selected imaging method, which are included in the image capturing conditions, in the image capturing condition setting section 150 .
[0068] The doctor or radiological technician operates the operating unit 159 in order to enter, in addition to the ID information of the radiation detecting device used by the selected image capturing apparatus, the ID information of all of the radiation detecting devices 52 , 62 , 72 that are present in the image capturing chambers 18 , 20 , 22 , as well as the ID information of any radiation detecting devices that are currently being charged by the cradle connected to the selected image capturing apparatus. The entered ID information is stored in the ID memory 146 . In addition to the ID information referred to above, the ID memory 146 may store ID information of all of the radiation detecting devices that are owned by the hospital. Instead of entering ID information through the operating unit 159 , bar codes representative of the ID information may be applied to the respective radiation detecting apparatus, and such bar codes may be read by a bar-code reader, not shown, in order to store the ID information of the radiation detecting apparatus in the ID memory 146 .
[0069] In the event that the doctor or radiological technician turns on the exposure switch 160 , the controller 142 outputs to the control device 40 the image capturing conditions that are set in the image capturing condition setting section 150 , and the ID information, which is stored in the ID memory 146 , of all of the radiation detecting devices 52 , 62 , 72 in the selected image capturing chamber.
[0070] In accordance with the image capturing conditions and the ID information, which are input to the control device 40 , the control device 40 activates the radiation detecting devices 52 , 62 , 72 of the respective image capturing apparatus 44 , 46 , 48 in the selected image capturing chamber, regardless of whether or not the power supply switch 94 has been turned on, thereby supplying the bias voltage Vb from the battery 88 to the radiation conversion panel 84 to ready the pixels 100 for storage of electric charges therein.
[0071] In a state where the radiation conversion panel 84 of each of the radiation detecting devices 52 , 62 , 72 of the respective image capturing apparatus 44 , 46 , 48 is ready to store electric charges therein, the control device 40 controls the radiation source 54 so as to emit radiation 56 .
[0072] After radiation 56 has been applied to the subject 42 (i.e., after a radiographic image of the subject 42 has been captured), the control device 40 successively acquires radiographic images obtained by the radiation detecting devices 52 , 62 , 72 , including the radiographic image obtained by the one radiation detecting device, and sends the acquired radiographic images to the consoles 24 , 26 , 28 .
[0073] More specifically, the control device 40 initially acquires a radiographic image obtained by the one radiation detecting device, and outputs the acquired radiographic image to the consoles 24 , 26 , 28 . Thereafter, the control device 40 preferentially acquires a radiographic image obtained by another radiation detecting device, which is close in proximity to the one radiation detecting device, and outputs the acquired radiographic image to the consoles 24 , 26 , 28 . Alternatively, the control device 40 may acquire a radiographic image obtained by the one radiation detecting device, and send the acquired radiographic image to the consoles 24 , 26 , 28 . Thereafter, the control device 40 may preferentially acquire a radiographic image obtained by another radiation detecting device, the imaging method of which is the same as the one radiation detecting device, and sends the acquired radiographic image to the consoles 24 , 26 , 28 .
[0074] While the control device 40 is successively acquiring radiographic images obtained by the radiation detecting devices 52 , 62 , 72 , if the image judging section 157 finds a significant (effective) radiographic image representative of the subject 42 , then the control device 40 immediately stops the process of acquiring radiographic images.
[0075] While radiographic images are successively being input by the control device 40 from the radiation detecting devices 52 , 62 , 72 to the consoles 24 , 26 , 28 , the image judging section 157 judges whether or not there is a significant radiographic image representative of the subject 42 .
[0076] More specifically, the image judging section 157 judges whether or not the radiographic image obtained by the one radiation detecting device is a significant radiographic image representative of the subject 42 . A significant radiographic image representative of the subject 42 is typified by a radiographic image, which is represented by digital image data the average luminance value or variance luminance value of which is equal to or greater than a prescribed threshold value, for example. More specifically, if the radiographic image represented by digital image data includes a white area representative of the subject 42 because the subject 42 absorbs a portion of the radiation 56 , then the average luminance value or variance luminance value of the image data is considered to be relatively high. Therefore, the image judging section 157 judges image data, the average luminance value or variance luminance value of which is equal to or greater than the threshold value, as a significant radiographic image representative of the subject 42 . The average luminance value or variance luminance value may be an average or variance value of the entire image data, or an average or variance value of a particular area of the image data that is representative of the subject 42 .
[0077] If the image judging section 157 determines that the radiographic image obtained by the one radiation detecting device is a significant radiographic image, then the image judging section 157 causes the control device 40 to cancel the process of acquiring radiographic images, and outputs the radiographic image obtained by the one radiation detecting device to the image processor 152 . The image processor 152 processes the radiographic image, and the display unit 156 displays the processed radiographic image.
[0078] If the image judging section 157 determines that the radiographic image obtained by the one radiation detecting device is not a significant radiographic image, and further determines that the radiographic image obtained by another radiation detecting device is a significant radiographic image, then the image judging section 157 causes the control device 40 to cancel the process of acquiring radiographic images, and warns (notifies) the doctor or radiological technician via the speaker 158 and/or the display unit 156 that a radiographic image of the subject 42 has been captured using a radiation detecting device (another radiation detecting device) other than the radiation detecting device (one radiation detecting device) set in the image capturing conditions.
[0079] At the same time that the image judging section 157 provides the warning through the speaker 158 and/or the display unit 156 , the image judging section 157 may output the radiographic image obtained by the other radiation detecting device to the image processor 152 , so that the display unit 156 may display the processed radiographic image.
[0080] If the image judging section 157 determines that neither one of the radiographic image obtained by the one radiation detecting device or the radiographic image obtained by another radiation detecting device is a significant radiographic image, then the image judging section 157 judges whether or not the radiographic image obtained by still another radiation detecting device is a significant radiographic image. If the radiographic image is a significant radiographic image, then the image judging section 157 warns the doctor or radiological technician again via the speaker 158 and/or the display unit 156 , and outputs the radiographic image obtained by the still other radiation detecting device to the image processor 152 , whereupon the display unit 156 displays the processed radiographic image.
[0081] In other words, in the case that there are a plurality of other radiation detecting devices in the image capturing chambers 18 , 20 , 22 , the control device 40 successively acquires radiographic images from the other radiation detecting devices, and then sends the acquired radiographic images to the consoles 24 , 26 , 28 until the image judging section 157 finds a significant radiographic image.
[0082] If the image judging section 157 determines that the radiographic image obtained by another radiation detecting device is a significant radiographic image, then the image judging section 157 assumes that the subject 42 should be irradiated with radiation 56 using the other radiation detecting device in a next imaging cycle, and replaces (switches from) the image capturing conditions, which are presently set in the image capturing condition setting section 150 , including the image capturing apparatus (one radiation detecting device), the imaging method, and the ID information, with (to) the image capturing conditions including the image capturing apparatus, the imaging method, and the ID information, which correspond to the other radiation detecting device.
[0083] It has been described above that the image judging section 157 judges whether or not the image data represent a significant radiographic image representative of the subject 42 based on the average luminance value or variance luminance value of the image data. However, the image judging section 157 may judge whether or not the image data represent a significant radiographic image representative of the subject 42 based on an average density value or variance density value of the image data. More specifically, if a radiographic image, which is represented by image data, includes a white area representative of the subject 42 because the subject 42 absorbs a portion of the radiation 56 , the average density value or variance density value of the image data is considered to be relatively low. Therefore, the image judging section 157 may judge image data, the average density value or variance density value of which is equal to or greater than another threshold value, as a significant radiographic image representative of the subject 42 , rather than judging image data based on the average luminance value or variance luminance value of the image data. The average density value or variance density value may be an average or variance value of the entire image data, or an average or variance value of a particular area of the image data that represents the subject 42 .
[0084] In the event that a radiographic image from the one radiation detecting device and a radiographic image from another radiation detecting device are acquired, the image judging section 157 may compare the two radiographic images (image data) with each other, and judge whether or not the two radiographic images are significant radiographic images representative of the subject 42 .
[0085] Each of the cradles 32 , 34 , 36 comprises a controller 162 , a transceiver 164 , a charging processor 166 , a display unit 168 , and an ID memory 170 .
[0086] The controllers 162 of the respective cradles 32 , 34 , 36 control components of the cradle 32 , 34 , 36 in their entirety.
[0087] The charging processors 166 charge the radiation detecting devices, which are connected to the cradles 32 , 34 , 36 outside the image capturing chambers 18 , 20 , 22 . The transceivers 164 send signals to and receive signals from the transceivers 144 of the consoles 24 , 26 , 28 .
[0088] Each of the controllers 162 stores the ID information of the radiation detecting device, which is currently being charged by the charging processor 166 , in the ID memory 170 .
[0089] Each of the display units 168 displays information (charge level, ID information, etc.) of the radiation detecting device that is currently being charged. In a case that the cradle and radiation detecting device of the radiation detecting device are connected to each other, the controller 162 may read the ID information from the ID memory 132 of the radiation detecting device, and store the read ID information in the ID memory 170 . Alternatively, the controller 162 may read ID information from a cradle thereof from the ID memory 146 of the console that is connected to a cradle of the console, and store the read ID information in the ID memory 170 .
[0090] The radiographic image capturing system 10 according to the present embodiment is basically constructed as described above. Operations (a radiographic image capturing method) of the radiographic image capturing system 10 with an emphasis on the console 24 and the image capturing chamber 18 will be described below with reference to the flowchart shown in FIG. 5 and the timing chart shown in FIG. 6 .
[0091] It is assumed that one radiation detecting device and one image capturing apparatus, which have been selected by the doctor or radiological technician in the image capturing chamber 18 , are the radiation detecting device 72 and the image capturing apparatus 48 , respectively, designed for an upright imaging process, whereas the other radiation detecting devices and the other image capturing apparatus are the radiation detecting device 62 and the image capturing apparatus 46 , and the radiation detecting device 52 and the image capturing apparatus 44 , respectively, which are designed for a supine imaging process. It is also assumed that, upon capturing of radiographic images, the power supply switches 94 are not turned on, but rather, the control device 40 activates the radiation detecting devices 52 , 62 , 72 . It is further assumed that, after radiographic images have been captured, the control device 40 acquires the radiographic images preferentially from radiation detecting devices that are closer in proximity to the one radiation detecting device 72 (i.e., the control device 40 successively acquires radiographic images from the radiation detecting device 72 , then from the radiation detecting device 62 , and then from the radiation detecting device 52 ).
[0092] In FIGS. 5 and 6 , it is assumed that the one image capturing apparatus 48 initially performs an upright imaging process normally on the subject 42 according to the image capturing conditions, and thereafter, regardless of the image capturing conditions for the upright imaging process set in the image capturing condition setting section 150 , the image capturing apparatus 46 performs a supine imaging process, instead of the upright imaging process performed by the image capturing apparatus 48 .
[0093] First, operation of the one image capturing apparatus 48 in the image capturing chamber 18 to perform an upright imaging process normally on the subject 42 according to the image capturing conditions will be described below.
[0094] In step S 1 , the transceiver 144 of the console 24 acquires order information from the RIS 14 via the in-hospital network 30 . The acquired order information is stored in the order information storage unit 148 .
[0095] In step S 2 , the doctor or radiological technician operates the operating unit 159 of the console 24 in order to display the order information stored in the order information storage unit 148 on the display unit 156 . Then, while observing the order information displayed on the display unit 156 , the doctor or radiological technician operates the operating unit 159 in order to select the image capturing apparatus 48 to be used in the imaging process, to select an imaging method (upright imaging process) for the image capturing apparatus 48 , and to enter the ID information of the radiation detecting device 72 . The image capturing apparatus 48 and the imaging method that have been selected, the entered ID information, and the information contained within the order information, which corresponds to the selected and entered items of information, are set as image capturing conditions in the image capturing condition setting section 150 . In addition, the doctor or radiological technician operates the operating unit 159 in order to enter ID information of all of the radiation detecting devices 52 , 62 , 72 that are present in the image capturing chamber 18 , together with ID information of any radiation detecting devices that are currently being charged by the cradle 32 connected to the console 24 . The entered ID information is stored in the ID memory 146 .
[0096] In step S 3 , the doctor or radiological technician performs a preparatory process for making the selected image capturing apparatus 48 ready to capture radiographic images.
[0097] More specifically, the doctor or radiological technician loads the image capturing base 70 with the radiation detecting device 72 , the battery 88 of which has been charged by the cradle 32 , and then positions the subject 42 with respect to the image capturing base 70 . Further, the doctor or radiological technician orients the radiation source 54 toward the subject 42 and the image capturing base 70 .
[0098] After the foregoing preparatory process has been completed, in step S 4 , the doctor or radiological technician turns on the exposure switch 160 in order to start an upright imaging process on the subject 42 .
[0099] As shown in FIG. 6 , upon the exposure switch 160 being turned on at time t 0 , the controller 142 sends the image capturing conditions set in the image capturing condition setting section 150 , together with the ID information of the radiation detecting devices 52 , 62 , 72 stored in the ID memory 146 , via the transceiver 144 to the transceiver 140 of the control device 40 . The control device 40 stores the image capturing conditions and the ID information received by the transceiver 140 in the memory 138 , and controls the radiation source 54 and the radiation detecting devices 52 , 62 , 72 according to the image capturing conditions and the ID information, so as to perform an upright imaging process on the subject 42 (irradiate the subject 42 with radiation 56 ).
[0100] Specifically, at time t 1 , the control device 40 controls the controller 90 via the transceivers 140 , 92 in order to activate the radiation detecting devices 52 , 62 , 72 . Under the control of the control device 40 , the controller 90 supplies a bias voltage Vb from the battery 88 to the radiation conversion panel 84 , thereby readying the pixels 100 for storage of electric charges therein.
[0101] At time t 2 , the control device 40 sends the image capturing conditions via the transceivers 140 , 136 to the controller 134 of the radiation source 54 . Based on the received image capturing conditions, the controller 134 outputs radiation 56 for a predetermined period (exposure time) from time t 2 to time t 3 . Radiation 56 is applied through the subject 42 to the radiation detecting device 72 in the image capturing base 70 . Then, radiation 56 that has passed through the subject 42 is directed toward the radiation conversion panel 84 in the radiation detecting device 72 .
[0102] If the radiation detecting device 72 is an indirect-conversion-type radiation detecting device, then the scintillator of the radiation conversion panel 84 in the radiation detecting device 72 emits visible light at an intensity that depends on the intensity of the radiation 56 . As described above, since the pixels 100 of the photoelectric conversion layer 101 are ready from time t 1 for storing electric charges under the bias voltage Vb, the pixels 100 convert the visible light into electric signals, and store the electric signals as electric charges.
[0103] At time t 4 when storage of electric charges in the pixels 100 is completed, the controller 90 supplies address signals to the line scanning driver 108 and the multiplexer 110 , so as to start a process of reading the electric charge information representative of a radiographic image of the subject 42 , which is held in the pixels 100 .
[0104] More specifically, the address decoder 112 of the line scanning driver 108 outputs a selection signal according to the address signal supplied from the controller 90 , so as to select one of the switches SW 1 , and the address decoder 112 supplies a control signal Von to the gates of the TFTs 106 , which are connected to the gate line 102 corresponding to the selected switch SW 1 . The address decoder 118 of the multiplexer 110 outputs a selection signal according to the address signal output from the controller 90 , so as to switch from one switch SW 2 to another, and then successively reads, through the signal lines 104 , radiographic images represented by electric charges held in the pixels 100 , which are connected from the gate line 102 selected by the line scanning driver 108 .
[0105] The radiographic images read from the pixels 100 connected to the gate line 102 are amplified by the respective amplifiers 114 , and then are sampled by the sample and hold circuits 116 . The radiographic images thus sampled are supplied through the multiplexer 110 to the A/D converter 120 , which converts the radiographic images into digital signals. Such digital radiographic image signals are stored in the image memory 130 by the controller 90 .
[0106] Similarly, the address decoder 112 of the line scanning driver 108 successively switches to other switches SW 1 according to the address signal supplied from the controller 90 . The radiographic images represented by electric charges held in the pixels 100 , which are connected from the respective gate lines 102 , are read through the signal lines 104 and stored in the image memory 130 through the multiplexer 110 , the A/D converter 120 , and the controller 90 .
[0107] The image memory 130 thus stores a radiographic image which is representative of the subject 42 in an upright position. In step S 4 , the image capturing process of the image capturing apparatus 48 is carried out as has been described above. As with the radiation detecting device 72 , the radiation detecting devices 52 , 62 of the other image capturing apparatus 44 , 46 also store electric charges therein and are capable of reading radiographic images. However, since radiation 56 is not applied to the radiation detecting devices 52 , 62 , the radiographic images read by the radiation detecting devices 52 , 62 are not representative of the subject 42 . From time t 3 to time t 4 , the console 24 invalidates the function of the exposure switch 160 (inhibits application of radiation 56 ), even if the doctor or radiological technician turns on the exposure switch 160 . Time t 6 indicates a time at which the operation sequence concerning one image capturing cycle, which is represented by the flowchart shown in FIG. 5 , is completed.
[0108] In step S 5 , after completion of the image capturing process, the control device 40 acquires via the controller 90 and the transceivers 92 , 140 the radiographic image stored in the image memory 130 of the radiation detecting device 72 and the ID information stored in the ID memory 132 , and sends the acquired radiographic image and ID information to the transceiver 144 . After the radiographic image and the ID information from the radiation detecting device 72 have been sent to the transceiver 144 , the control device 40 sends via the controller 90 and the transceivers 92 , 140 the radiographic image stored in the image memory 130 of the radiation detecting device 62 , which is close in proximity to the radiation detecting device 72 , and the ID information stored in the ID memory 132 to the transceiver 144 . Therefore, the transceiver 144 successively receives the ID information and the radiographic image from the radiation detecting device 72 , as well as the ID information and the radiographic image from the radiation detecting device 62 , and then stores the respective ID information and the radiographic images in the image memory 154 .
[0109] In step S 6 , the image judging section 157 judges whether or not the radiographic image selected by the doctor or radiological technician from among the two radiographic images stored in the image memory 154 is a significant radiographic image representative of the subject 42 .
[0110] As described above, since the image capturing apparatus 48 has imaged the subject 42 in an upright position and the radiographic image from the radiation detecting device 72 is representative of the subject 42 , the average luminance value or variance luminance value of the radiographic image (image data) is equal to or greater than the threshold value. Inasmuch as the average luminance value or variance luminance value of the image data is equal to or greater than the threshold value, the image judging section 157 judges that the radiographic image from the radiation detecting device 72 is a significant radiographic image (step S 6 : YES), and further judges that the radiographic image from the radiation detecting device 62 , which is stored in the image memory 154 , is unnecessary.
[0111] Since the image judging section 157 has found a significant radiographic image, the image judging section 157 instructs the control device 40 to cancel the process of acquiring radiographic images, and erases the ID information and the radiographic image of the radiation detecting device 62 from the image memory 154 . The image judging section 157 supplies the ID information and the radiographic image (significant radiographic image) of the radiation detecting device 72 , which are stored in the image memory 154 , to the image processor 152 .
[0112] The image processor 152 performs a predetermined image processing routine on the supplied radiographic image from the radiation detecting device 72 (step S 7 ), and displays the processed radiographic image on the display unit 156 (step S 8 ).
[0113] In the period from time t 4 to time t 5 , the process of acquiring radiographic images from the radiation detecting devices 52 , 62 , 72 is completed. The radiographic image displayed on the display unit 156 is sent through the in-hospital network 30 to the viewer 16 for interpretation and diagnosis thereof by the doctor.
[0114] An upright imaging process, which is performed normally on the subject 42 by the image capturing apparatus 48 , has been described above.
[0115] A supine imaging process, which is performed by the image capturing apparatus 46 instead of the upright imaging process performed by the image capturing apparatus 48 , regardless of the fact that the doctor or radiological technician has selected the image capturing apparatus 48 and the image capturing conditions for the image capturing apparatus 48 have been set in the image capturing condition setting section 150 , will be described below.
[0116] In one instance, the doctor or radiological technician plans to perform an upright imaging process with the image capturing apparatus 48 according to the image capturing conditions, but due to a failure of the image capturing apparatus 48 or the radiation detecting device 72 , the doctor or radiological technician determines instead to perform a supine imaging process, which is performed by the image capturing apparatus 46 , instead of the upright imaging process performed by the image capturing apparatus 48 . In another instance, if the imaging method is changed and a supine imaging process is performed by the image capturing apparatus 46 , then it is presumed that the doctor or radiological technician should have operated the operating unit 159 to change the image capturing conditions registered in the image capturing condition setting section 150 , but in fact, the doctor or radiological technician forgot to change the set image capturing conditions.
[0117] In step S 3 , the doctor or radiological technician loads the image capturing base 70 with the radiation detecting device 72 , the battery 88 of which has been charged by the cradle 32 . Then, the doctor or radiological technician positions the subject 42 with respect to the image capturing base 60 , and orients the radiation source 54 toward the subject 42 and the image capturing base 60 .
[0118] After completion of this preparatory process, in step S 4 , the doctor or radiological technician turns on the exposure switch 160 to initiate a supine imaging process on the subject 42 .
[0119] Even though the image capturing apparatus 48 indicated by the image capturing conditions set in the image capturing condition setting section 150 and the image capturing apparatus 46 which actually performs the image capturing process are different from each other, and the doctor or radiological technician recognizes that a supine imaging process is to be performed by the image capturing apparatus 46 , since the set image capturing conditions have not been changed, the console 24 recognizes that an image capturing process will be performed under the image capturing conditions (upright imaging process), which are currently set in the image capturing condition setting section 150 .
[0120] As shown in FIG. 6 , if the exposure switch 160 is turned on at time t 0 , the console 24 sends the image capturing conditions and the ID information of the radiation detecting devices 52 , 62 , 72 , which are stored in the ID memory 146 , to the control device 40 . The control device 40 stores the received image capturing conditions and ID information in the memory 138 , and controls the radiation source 54 and the radiation detecting devices 52 , 62 , 72 in accordance with the image capturing conditions and the ID information. The control device 40 controls the radiation source 54 and the radiation detecting devices 52 , 62 , 72 , while recognizing that an upright imaging process is to be performed based on the image capturing conditions and the ID information.
[0121] At time t 1 , the control device 40 activates the radiation detecting devices 52 , 62 , 72 , thereby readying the pixels 100 for storage of electric charges therein. At time t 2 , the control device 40 sends the image capturing conditions to the radiation source 54 . The radiation source 54 irradiates the subject 42 with radiation 56 for a given exposure time from time t 2 to time t 3 . Radiation 56 that has passed through the subject 42 is led to the radiation conversion panel 84 in the radiation detecting device 62 . The scintillator of the radiation conversion panel 84 emits visible light at an intensity that depends on the intensity of the radiation 56 . The pixels 100 convert the visible light into electric signals and store the electric signals as electric charges.
[0122] At time t 4 when storage of electric charges in the pixels 100 is completed, the controller 90 supplies address signals to the line scanning driver 108 and the multiplexer 110 in order to initiate a process of reading the electric charge information held in the pixels 100 , which is representative of a radiographic image of the subject 42 , and the controller 90 stores the read radiation image in the image memory 130 .
[0123] At this time, the image memory 130 of the radiation detecting device 62 stores the radiographic image, which is representative of the subject 42 in a supine position. Therefore, the radiographic image from the radiation detecting device 72 , which has been selected by the doctor or radiological technician, and the radiographic image from the other radiation detecting device 52 are not representative of the subject 42 .
[0124] In step S 5 , the control device 40 acquires the ID information and the radiographic image from the radiation detecting device 72 , and sends the ID information and the radiographic image to the transceiver 144 . Thereafter, the control device 40 acquires the radiographic image and the ID information from the radiation detecting device 62 , and sends the radiographic image and the ID information to the transceiver 144 .
[0125] In step S 6 , the image judging section 157 judges whether or not the radiographic image selected by the doctor or radiological technician from the two radiographic images stored in the image memory 154 is a significant radiographic image representative of the subject 42 .
[0126] As described above, inasmuch as the image capturing apparatus 46 has captured a radiographic image of the subject 42 in a supine position, the radiographic image from the radiation detecting device 72 is not representative of the subject 42 , and hence the average luminance value or variance luminance value of the radiographic image (image data) is smaller than the threshold value. Therefore, the image judging section 157 determines that the radiographic image from the radiation detecting device 72 is not a significant radiographic image (step S 6 : NO). The image judging section 157 then determines whether or not the radiographic image from the radiation detecting device 62 is a significant radiographic image representative of the subject 42 .
[0127] Since the radiographic image from the radiation detecting device 62 is representative of the subject 42 , and hence the average luminance value or variance luminance value of the image data thereof is equal to or greater than the threshold value, the image judging section 157 determines that the radiographic image from the radiation detecting device 72 is a significant radiographic image. In order to indicate to the radiological technician that the radiographic image according to the image capturing conditions (the radiographic image obtained from the image capturing apparatus 48 in the upright imaging process) and the actually produced radiographic image (the radiographic image obtained from the image capturing apparatus 46 in the supine imaging process) do not agree with each other, the image judging section 157 produces an audible speech warning through the speaker 158 and/or displays a visual warning through the display unit 156 (step S 9 ).
[0128] Inasmuch as the radiographic image from the radiation detecting device 62 is a significant radiographic image, the image judging section 157 judges as unnecessary the radiographic image from the radiation detecting device 72 , which is stored in the image memory 154 . Since the image judging section 157 has found the significant radiographic image, the image judging section 157 instructs the control device 40 to cancel the process of acquiring radiographic images, and erases the ID information and the radiographic image of the radiation detecting device 72 from the image memory 154 . The image judging section 157 supplies the ID information and the radiographic image (significant radiographic image) of the radiation detecting device 62 to the image processor 152 .
[0129] The image processor 152 performs a predetermined image processing routine on the supplied radiographic image from the radiation detecting device 62 (step S 7 ), and displays the processed radiographic image on the display unit 156 (step S 8 ).
[0130] The image judging section 157 also is capable of judging whether or not the radiographic image displayed on the display unit 156 is a radiographic image captured by the image capturing apparatus 48 under the image capturing conditions (step S 10 ). As described above, since the radiographic image displayed on the display unit 156 is a radiographic image captured by the image capturing apparatus 46 , which is different from the image capturing apparatus 48 represented by the image capturing conditions (step S 10 : NO), the image judging section 157 changes the image capturing conditions for the image capturing apparatus 48 , which are currently set in the image capturing condition setting section 150 , into image capturing conditions for the image capturing apparatus 46 , based on the assumption that a next radiographic image will be captured by the image capturing apparatus 46 that has captured the radiographic image displayed on the display unit 156 (step S 11 ). As a result, the image capturing apparatus 46 will be selected for capturing a subsequent radiographic image, thereby preventing the image capturing apparatus 46 from being unselected due to an oversight.
[0131] A supine imaging process, which is carried out by the image capturing apparatus 46 instead of the upright imaging process carried out by the image capturing apparatus 48 , has been described above.
[0132] If a supine imaging process is performed using the image capturing apparatus 44 instead of using the image capturing apparatus 46 , then after having issued a warning in step S 9 , the image judging section 157 instructs the control device 40 to acquire the ID information and the radiographic image from the radiation detecting device 52 of the image capturing apparatus 44 . Control then returns to step S 5 , in which the control device 40 is instructed by the image judging section 157 to acquire the ID information and the radiographic image from the radiation detecting device 52 , and the control device 40 sends the ID information and the radiographic image, which have been acquired, to the console 24 . Therefore, the image judging section 157 performs the process from step S 6 again.
[0133] According to the present embodiment, as described above, the control device 40 acquires both the radiographic image from one radiation detecting device (one image capturing apparatus), which is selected by the doctor or radiological technician by operating the operating unit 159 , and the radiographic image from at least one other radiation detecting device (other image capturing apparatus) that differs from the one radiation detecting device, and the control device 40 sends the acquired radiographic images to the consoles 24 , 26 , 28 .
[0134] If radiation 56 is applied through the subject 42 to the one radiation detecting device, then the control device 40 acquires a radiographic image from the one radiation detecting device, thereby acquiring a radiographic image representative of the subject 42 . If radiation 56 is applied through the subject 42 to the other radiation detecting device, then the control device 40 acquires a radiographic image from the other radiation detecting device, thereby acquiring a radiographic image representative of the subject 42 .
[0135] More specifically, in a case that the one image capturing apparatus is changed to the other image capturing apparatus in order to capture a radiographic image, it is desirable for the doctor or radiological technician to operate the operating unit 159 , so as to select the other image capturing apparatus before the radiographic image is captured. However, the doctor or radiological technician may possibly fail to select the other image capturing apparatus for capturing a radiographic image, and thus a radiographic image may not be acquired from the other image capturing apparatus. According to the present embodiment, regardless of whether or not the doctor or radiological technician has actively operated the operating unit 159 in order to select the other image capturing apparatus, both the radiographic image from the one radiation detecting device and the radiographic image from the other radiation detecting device are acquired, thereby reliably acquiring a radiographic image representative of the subject 42 .
[0136] According to the present embodiment, therefore, regardless of whether or not the one radiation detecting device or the other radiation detecting device has been used to capture a radiographic image, the control device 40 reliably acquires a radiographic image that is representative of the subject 42 . As a result, the subject 42 is prevented from being exposed to radiation 56 needlessly.
[0137] The image judging section 157 of each of the consoles 24 , 26 , 28 judges whether or not the radiographic image from the one radiation detecting device is a significant radiographic image representative of the subject 42 . Therefore, it is possible to determine whether or not the radiographic image from the one radiation detecting device is a significant radiographic image representative of the subject 42 .
[0138] If the image judging section 157 determines that the radiographic image from the one radiation detecting device is not a significant radiographic image, then the image judging section 157 issues a warning through the speaker 158 and/or the display unit 156 . Therefore, the doctor or radiological technician can easily recognize that an image capturing process has been carried out, without being required to operate the operating unit 159 in order to select the other radiation detecting device.
[0139] If the image judging section 157 determines that the radiographic image from the one radiation detecting device is not a significant radiographic image, then the image judging section 157 judges whether or not the radiographic image from the other radiation detecting device is a significant radiographic image. Therefore, it is possible to determine whether or not the radiographic image from the other radiation detecting device is a significant radiographic image.
[0140] If the image judging section 157 determines that the radiographic image from the one radiation detecting device is not a significant radiographic image, then the control device 40 successively acquires radiographic images from the other radiation detecting devices until the image judging section 157 finds a significant radiographic image. Therefore, a significant radiographic image can reliably be acquired.
[0141] According to the present embodiment, in the event that the doctor or radiological technician operates the operating unit 159 in order to select the one radiation detecting device, the doctor or radiological technician also designates an imaging method to be carried out at the time that radiation 56 is applied to the subject 42 using the one radiation detecting device. In this case, the control device 40 acquires a radiographic image preferentially from a radiation detecting device, from among the other radiation detecting devices, which produces a radiographic image according to the imaging method, or acquires a radiographic image preferentially from another radiation detecting device that is close in proximity to the one radiation detecting device.
[0142] If the one radiation detecting device is not used, but rather another radiation detecting device is used to capture a radiographic image, then it is assumed to be highly likely to have captured a radiographic image using another radiation detecting device, according to the same imaging method as the imaging method (e.g., upright imaging process or supine imaging process) of the one radiation detecting device, or to have captured a radiographic image using another radiation detecting device that is closest in proximity to the one radiation detecting device. The control device 40 thus acquires a radiographic image preferentially from another radiation detecting device according to the same imaging method, or from another radiation detecting device that is closest in proximity to the one radiation detecting device. Consequently, it is possible to acquire a significant radiographic image quickly and reliably.
[0143] For example, if radiographic images are to be acquired according to imaging methods, then the radiographic images may be acquired according to the following sequence.
[0144] Assuming that the one radiation detecting device is the radiation detecting device 72 , then radiographic images are acquired according to a sequence in which the radiation detecting device 72 in the upstanding imaging process→the radiation detecting device 62 in the supine imaging process →the radiation detecting device 52 (in the supine imaging process) are selected in this order. Assuming that the one radiation detecting device is the radiation detecting device 62 , then radiographic images are acquired according to a sequence in which the radiation detecting device 62 in the supine imaging process→the radiation detecting device 52 (in the supine imaging process)→the radiation detecting device 72 in the upstanding imaging process are selected in this order.
[0145] If the image judging section 157 determines that the radiographic image from the other radiation detecting device is a significant radiographic image, then the image judging section 157 switches from the image capturing conditions for the one radiation detecting device, which are set in the image capturing condition setting section 150 (selection of the one radiation detecting device), to the image capturing conditions for the other radiation detecting device (selection of the other radiation detecting device). In this case, since it is assumed that a subsequent imaging cycle will be carried out using the other radiation detecting device, which has produced the significant radiographic image, the image judging section 157 automatically switches from selecting the one radiation detecting device to selecting the other radiation detecting device, thereby preventing the other radiation detecting device from being unselected due to an oversight in the next imaging cycle.
[0146] Each of the consoles 24 , 26 , 28 displays, on the display unit 156 , the radiographic image that the image judging section 157 has judged as being a significant radiographic image. Accordingly, the doctor can interpret the significant radiographic image for facilitating diagnosis.
[0147] Since the ID memory 146 stores ID information of all of the radiation detecting devices 52 , 62 , 72 that are present in the image capturing chambers 18 , 20 , 22 , the control device 40 stores the ID information in the ID memory 146 in the memory 138 , and thereafter acquires radiographic images from the radiation detecting devices 52 , 62 , 72 that are present in the image capturing chambers 18 , 20 , 22 according to such ID information and the image capturing conditions.
[0148] Inasmuch as radiographic images are acquired only from the radiation detecting devices 52 , 62 , 72 that are present in the image capturing chambers 18 , 20 , 22 , it is possible to reliably prevent an image acquiring process from being performed in error using radiation detecting devices that are present outside of the image capturing chambers 18 , 20 , 22 , e.g., radiation detecting devices that are currently being charged by the cradles 32 , 34 , 36 and radiation detecting devices in image capturing chambers in which radiographic images are not being captured. Further, the process of acquiring radiographic images can be carried out efficiently.
[0149] Since each radiation conversion panel 84 is made ready to store electric charges before radiation 56 is applied to the subject 42 , it is not necessary to irradiate the radiation detecting devices 52 , 62 , 72 with triggering radiation 56 in order to instruct the radiation conversion panel 84 to store electric charges therein prior to the main image capturing process. Therefore, the arrangement for instructing the storage of electric charges is simplified, and the dose of radiation to which the subject 42 is exposed can be reduced.
[0150] In the above description, the control device 40 and the consoles 24 , 26 , 28 are separate from each other. However, the control device 40 may be dispensed with, and the function of the control device 40 to acquire radiographic images may be possessed by the controller 142 .
[0151] If the subject 42 to be imaged is thick bodied, then the dose of radiation 56 that reaches the radiation detecting device, which is used to capture a radiographic image, may possibly be smaller than the dose of radiation that leaks to other radiation detecting devices. According to the present embodiment, therefore, correlative data between mAs values together with the thickness of the subject 42 , and patterns of radiographic images produced upon leakage of radiation may be registered in advance in the image capturing condition setting section 150 . In this case, a radiographic image, which is generated from a thick bodied subject, may be corrected using such registered data and patterns.
[0152] It has been described above that a doctor or radiological technician operates the operating unit 159 in order to register an imaging method in the image capturing condition setting section 150 , whereupon the doctor or radiological technician orients the radiation source 54 toward the subject 42 in a preparatory process. However, according to the present embodiment, the present invention is not limited to such details in the preparatory process. Imaging methods and movements of the radiation source 54 may be associated with each other, and in the event that an imaging method is registered in the image capturing condition setting section 150 , the radiation source 54 may be automatically moved in accordance with the imaging method. Alternatively, in the event that the radiation source 54 is moved in the preparatory process, an imaging method, which depends on the moved radiation source 54 , may automatically be registered in the image capturing condition setting section 150 .
[0153] Furthermore, if an imaging method is changed from the image capturing apparatus 48 to the image capturing apparatus 46 , the dose of radiation 56 according to the image capturing conditions may be changed depending on the changed imaging method, and the changed dose of radiation 56 may be output from the radiation source 54 .
[0154] The present invention is not limited to the embodiment described above, but various changes and modifications may be made without departing from the scope of the invention. | The disclosed radiograph acquisition device has: a selection unit that selects one radiation detection device from among a plurality of radiation detection devices that can convert radiation to radiographs; and an acquisition unit that acquires the radiograph of one radiation detection device when radiation is radiated at a subject, and the radiograph of at least one other radiation detection device aside from the one radiation device among the plurality of radiation detection devices. | 0 |
TECHNICAL FIELD
[0001] The invention relates to a belt retractor, in particular to a belt retractor comprising a force-limiting arrangement.
BACKGROUND OF THE INVENTION
[0002] From DE-A-103 43 534 a belt retractor is known comprising a belt spool rotatably mounted in a frame, a disc adapted to be blocked against rotation on the frame, and a force-limiting arrangement with a cutting body which is adapted to be guided into a coupling position in which the cutting body couples the belt spool to the disc such that upon a relative rotation between the disc and the belt spool, the cutting body cuts material. In this belt retractor, in addition to a first force limitation by means of a torsion rod, at the same time a second force limitation takes place by cutting working of material, which in particular through the parameters of width and depth of cut partially permits a progressive, degressive or constant force level pattern. The force level and its pattern, though, are identical for all occupants.
[0003] It is an object of the invention to provide a belt retractor which allows a more flexible setting of the force level.
BRIEF SUMMARY OF THE INVENTION
[0004] The belt retractor according to the invention comprises a belt spool rotatably mounted in a frame, a disc adapted to be blocked against rotation on the frame, and a force-limiting arrangement with a cutting body which is adapted to be guided into a coupling position in which the cutting body couples the belt spool to the disc such that upon a relative rotation between the disc and the belt spool, the cutting body cuts material, the force-limiting arrangement having a guiding-in mechanism which guides the cutting body into the coupling position as a function of accident-related data. Coming into consideration as accident-related data are, in particular, body data of the vehicle occupant, seating position data or data which are representative of the severity of the accident. This data can be determined for example by sensors or in another manner, such as for example by determining the length of the belt webbing withdrawn or the angular acceleration or rotational speed of the belt spool before a blocking. The belt retractor according to the invention therefore allows a force limitation which can be better adapted to the respective circumstances. In particular, the weight and/or the height of the occupant can be taken into account to a sufficient extent for an optimized setting of the force limitation.
[0005] An advantageous development of the belt retractor according to the invention makes provision that the guiding-in mechanism has at least one oblique plane formed on the belt spool or on the disc, the cutting body being adapted to slide on the disc into the coupling position.
[0006] According to a first embodiment, the cutting body is an inertial body, or the cutting body is coupled to an inertial body, which on exceeding a particular angular acceleration or rotational speed and subsequent blocking of the belt spool is moved into the coupling position owing to its inertia or the centrifugal force acting on it. Thereby, it can be achieved that the additional force limitation caused by material cutting takes place only for occupants with a high body weight. In the case of an abrupt deceleration of the vehicle, shortly before the blocking of the belt spool, in the case of a heavy occupant a more rapid belt webbing withdrawal takes place than in the case of a light occupant, who shows a “slower” forward displacement. Only in the first case are the inertia forces onto the cutting body great enough for a guiding-in into the coupling position.
[0007] It is expedient to provide a locking mechanism which holds the cutting body in an initial position. Thereby it is ensured that the cutting body under normal circumstances is not unintentionally guided into the coupling position.
[0008] The locking mechanism can have a pre-stressing spring and/or a mechanical stop.
[0009] According to a second embodiment of the belt retractor according to the invention, the guiding-in mechanism is coupled to a switching mechanism of the belt retractor with which, on rotation of the belt spool, switching functions can be carried out. Such a switching mechanism is known per se and is based on a planetary gear or a control disc coupled to the belt spool via a reduction gear. The switching mechanism is used in particular for a so-called child safety function which is usually activated after a complete withdrawal of the belt webbing. It ensures that the fully withdrawn belt webbing in fact can be wound onto the belt spool again, but can no longer be withdrawn therefrom, in order to thus make possible a reliable fastening of a child's seat on a vehicle seat by means of a safety belt. The underlying mechanism, which provides for a switching process dependent on the length of the belt webbing withdrawn, can be made use of for the invention. Thus, after withdrawal of a particular belt webbing length, a switching process can be carried out, which leads to a guiding-in of the cutting body into the coupling position. As the length of belt webbing withdrawn is representative of the size of an occupant, therefore automatically a size-dependent setting of the force limitation level takes place.
[0010] A coupling of the guiding-in mechanism to the switching mechanism can take place in that the guiding-in mechanism has a guiding-in element, connected with the cutting body, which is movable by the switching mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a diagrammatic sectional view of a belt retractor with a force-limiting arrangement;
[0012] FIG. 2 shows a diagrammatic sectional view of a guiding-in mechanism of the force-limiting arrangement according to a first embodiment;
[0013] FIGS. 3, 4 show two variants of the guiding-in mechanism of FIG. 2 ;
[0014] FIG. 5 shows a diagrammatic sectional view of a guiding-in mechanism of the force-limiting arrangement according to a second embodiment;
[0015] FIG. 6 shows a variant of the guiding-in mechanism of FIG. 5 ;
[0016] FIG. 7 a shows a diagrammatic end face view of a guiding-in mechanism of the force-limiting arrangement according to a third embodiment;
[0017] FIG. 7 b shows a sectional view along the line B-B in FIG. 7 a; and
[0018] FIG. 8 shows a diagram of forces of the force-limiting arrangement according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The belt retractor shown diagrammatically in FIG. 1 has a frame 10 and a belt spool 12 rotatably mounted in the frame 10 . A disc 16 , which can rest against the frame 10 so as to be blocked against rotation by a blocking mechanism 18 , is joined to a flange 14 of the belt spool 12 . The disc 16 is connected for joint rotation with the flange 14 of the belt spool 12 up to a certain torque, for example by shear pins. In the hollow interior of the belt spool 12 , a torsion rod 20 is arranged, which is coupled at one axial end for rotation with the disc 16 , and at the opposite end for rotation with the belt spool 12 . A cutting body 22 rests on the disc 16 . The cutting body 22 can be raised by a guiding-in mechanism in the axial direction (in relation to the rotation axis of the belt spool 12 and the disc 16 ) from an initial position into a coupling position, in which it projects axially beyond the end face of the disc 16 facing the flange 14 .
[0020] In FIG. 2 a first embodiment of the belt retractor is shown, in which the cutting body 22 rests inter alia on two oblique planes 24 formed in a depression of the end face of the disc 16 . The cutting body 22 , which is illustrated in FIG. 2 in an initial position, is held by a locking mechanism in the axial direction. The locking mechanism comprises here a mechanical stop in the form of an extension 26 , formed integrally with the cutting body 22 , which engages into an associated mounting 28 on the disc 16 . In addition, the cutting body 22 is secured by a bolt 30 (or a screw) screwed into the cutting body 22 , which penetrates the disc 16 in an oblong hole 32 . A spring 36 arranged between the disc 16 and the head 34 of the bolt 30 braces the cutting body 22 towards the disc 16 . Generally, one of the two measures is sufficient in order to hold the cutting body 22 in the initial position under normal circumstances.
[0021] In a case of blocking, triggered in a vehicle-sensitive or belt webbing-sensitive manner, the disc 16 is blocked by the blocking mechanism 18 against rotation on the frame 10 of the belt retractor. Thereby also the belt spool 12 is coupled non-rotatably to the frame 10 via the torsion rod 20 , so that further rotation of the belt spool 12 in the belt webbing withdrawal direction A is prevented. On exceeding a predetermined belt load, however, the torsion rod 20 twists and permits a belt force limiting rotation of the belt spool 12 relative to the disc 16 .
[0022] In addition to the known belt force limitation by the torsion rod 20 , an additional force limitation can take place through a guiding in of the cutting body 22 into the coupling position. Whether or not such a guiding in takes place depends on the angular acceleration or the rotational speed of the belt spool 12 before its blocking. The belt webbing withdrawal taking place before the blocking of the belt spool 12 brings about a rotation of the belt spool 12 , which is caused by the forward movement of the occupant in the case of an abrupt deceleration of the vehicle, the extent of the angular acceleration or the rotational speed depending in particular on the weight of the occupant.
[0023] The oblique planes 24 and the cutting body 22 are coordinated with each other such that on exceeding a particular rotational speed of the belt spool 12 in the belt webbing withdrawal direction and subsequent blocking of the belt spool 12 , the cutting body 22 , owing to its mass moment of inertia, overcomes the static friction and the pre-stressing force of the spring 36 and slides on the oblique planes 24 into the coupling position. With this movement of the cutting body 22 , the extension 26 comes out of engagement with the mounting 28 , and the bolt 30 is displaced in the oblong hole 32 until the cutting body 22 comes to lie on the elevated support surfaces 38 . A cutting edge 40 of the cutting body 22 projects in this elevated position into a recess 42 in the flange 14 of the belt spool 12 . Upon a rotation of the belt spool 12 relative to the disc 16 in the belt webbing withdrawal direction, accompanied by twisting of the torsion rod 20 , the cutting edge 40 of the cutting body 22 comes into engagement with the material of the flange 14 , a shoulder 44 of the recess 42 pressing the cutting body 22 against a stop 46 of the disc 16 . The bolt 30 is dimensioned such that with this thrust movement it is sheared off. The sheared off part of the bolt 30 is pushed into a free space in which previously a part of the cutting body 22 was received. A further relative rotation between the belt spool 12 and the disc 16 is now only possible by the cutting edge 40 of the cutting body 22 cutting a chip out of the flange 14 .
[0024] Therefore, an energy conversion takes place through material cutting, which is effected parallel to the energy conversion through the twisting of the torsion rod 20 . The profile of the force level of the additional limitation as a function of the rotation angle of the belt spool 12 is determined substantially by the width and depth of cut.
[0025] In FIGS. 3 and 4 two variants of the guiding-in mechanism are shown, in which the cutting body 22 is held by an inertia spring 48 and respectively 50 arranged between the flange 14 of the belt spool 12 and the cutting body 22 and respectively between the stop 46 of the disc 16 and the cutting body 22 .
[0026] Whereas in the first embodiment shown in FIGS. 2 to 4 the guiding-in mechanism is formed substantially solely by the oblique planes 24 , in the second, similarly constructed embodiment shown in FIGS. 5 and 6 , the guiding-in of the cutting body 22 takes place by means of a switching element 52 (only illustrated symbolically). The switching element 52 is part of a switching mechanism known per se, with which switching functions can be carried out on rotation of the belt spool 12 . The switching mechanism is designed so that the switching element 52 carries out a switching movement after withdrawal of a particular length of belt webbing from the belt spool 12 . In so doing, the switching element 52 engages the bolt 30 such that the latter raises the cutting body 22 into the coupling position. In this embodiment, the bolt 30 therefore serves as guiding-in element, but just as in the first embodiment is sheared off by the thrust movement of the flange 14 of the belt spool 12 .
[0027] In contrast to the first embodiment, in this embodiment a guiding-in of the cutting body 22 does not take place as a function of the angular acceleration or the rotational speed of the belt spool 12 before its blocking, but rather as a function of the length of the belt webbing withdrawn or the belt webbing remaining on the belt spool 12 , which depends substantially on the size of the occupant.
[0028] FIG. 6 shows a variant of the second embodiment. Here, the pre-stressing spring 36 is arranged between the disc 16 and the cutting body 22 , so that the cutting body 22 is pre-stressed into the coupling position, but is held in the initial position by the switching element 52 . By an actuation of the switching element 52 , the cutting body 22 is guided from the initial position into the coupling position shown in FIG. 6 .
[0029] FIGS. 7 a and 7 b illustrate a third embodiment the guiding-in mechanism of which is constructed similarly to that of the first embodiment. Here, the cutting body 22 is guided into the coupling position as a function of the centrifugal force F Z acting on the cutting body 22 . Depending on the physical constitution of the vehicle occupant, in fact a significant difference in the speed of belt webbing withdrawal and hence in the rotational speed of the belt spool 12 or the disc 16 can be seen during belt webbing withdrawal. The mechanical implementation of the guiding-in mechanism of this embodiment proceeds from the finding that this speed can only differ when a resistance has arisen at the belt webbing, because it is not until then that the specific kinetic energy of the occupant also has an influence (E=½ mv 2 ).
[0030] Accordingly, provision is made that initially a force limitation takes place on a basic level by means of the torsion rod 20 only. (This level could be designed, for example, as a predefined ideal level for a so-called 5% occupant.) But if the rotational speed of the belt spool 12 exceeds a specific limiting value, the cutting body 22 is additionally connected owing to the higher centrifugal force F Z , so that the level of force limitation is raised. (This level may be designed as a predefined ideal level for 50% or 95% occupants.) If, on the other hand, the rotational speed of the belt spool 12 remains below the predefined limiting value, the switching process does not occur and the force limitation is effected at the lower level.
[0031] FIG. 8 shows the different levels of force limitation in a diagram in which the force limitation is illustrated as a function of the belt webbing withdrawal.
[0032] In all embodiments, the guiding-in of the cutting body 22 into the coupling position can also take place by means of a control element which is coupled to the cutting body 22 and is moved as a function of the angular acceleration/rotational speed of the belt spool or the belt webbing withdrawal length.
[0033] The pre-stressing springs 36 , 48 , 50 of the different embodiments/variants can be designed such that they serve not only for securing the cutting body or a control element, but also for setting the inertia, i.e. the necessary angular acceleration of the belt spool for a guiding-in of the cutting body into the coupling position, and hence the moment of guiding in. The pre-stressing springs can be formed in particular by the usual inertia springs in belt retractors.
[0034] It is also possible to combine features of different embodiments with each other. In addition, the cutting body 22 can, as an alternative, be arranged on the belt spool 12 and cut material on the disc 16 . | A belt retractor has a belt spool ( 12 ) rotatably mounted in a frame ( 10 ), a disc adapted to be blocked against rotation on the frame ( 10 ), and a force-limiting arrangement. The force-limiting arrangement includes a cutting body ( 22 ) which is adapted to be guided into a coupling position in which the cutting body ( 22 ) couples the belt spool ( 12 ) to the disc ( 16 ) such that upon a relative rotation between the disc ( 16 ) and the belt spool ( 12 ), the cutting body ( 22 ) cuts material. The force-limiting arrangement has a guiding-in mechanism which guides the cutting body ( 22 ) into the coupling position as a function of accident-related data. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a shed forming device designed to be installed on a weaving machine.
2. Brief Description of the Related Art
In the textile field, it is known that, on a Jacquard-type weaving machine, the formation of the weaving shed for the warp yarns of the weaving machine takes place by passing each warp yarn through the eyelet of a heddle whereof one end is connected to a spring and the other end is connected to a funicular element. The funicular element or harness is a yarn, a single- or multi-strand cable that can be wound around the pulley and follow a path defined by guide members. The principle of winding the harness around the pulley is known, for example from WO-A-4 433 704 or from EP-A-0 933 456. In the equipment of U.S. Pat. No. 4,433,704, a mechanical shaft drives some pulleys for winding the funicular elements, without use of a rotary electric actuator. In the equipment of EP-A-0 933 456, the pulley is driven by an electric actuator that controls the travel of the harness secured to the pulley. It is also known from EP-A-0 926 280 to use housings comprising up to sixteen subassemblies formed by a pulley and an associated actuator. The housings grouping together these subassemblies have the advantage of saving space on the weaving machine. Up to forty of these housings are assembled on either side of an aluminum profile that ensures their mechanical support and cooling. Each actuator commands a pulley that is removably assembled. The set of the pulleys, harnesses, heddles, springs and associated guide elements requires a significant number of assembly operations. EP-A-1 493 857 discloses a method and a device making it possible to place and disassemble sixteen pulleys from a housing simultaneously. These devices significantly improve the quality of maintenance operations, in terms of practicality and length.
The size of a weaving machine is the result of a compromise between cost and bulk imperatives, taking into account the diversity of the applications that may be involved. In parallel, the development of new weaving techniques, such as 3D weaving, requires both an increase in travel and admissible loads on the driving means of the harnesses of the weaving machine of the Jacquard type.
SUMMARY OF THE INVENTION
The invention more particularly aims to meet these objectives by proposing a new weaving shed device for a weaving machine that is easy and cost-effective to manufacture and allows a significant increase in the travel and admissible loads on the driving means of a harness.
To that end, the invention relates to a shed forming device for a weaving machine comprising at least one rotary electric actuator provided for winding around a pulley of the funicular element controlling at least one heddle, an output shaft of the actuator rotating around a first axis. According to the invention, the shaft of the actuator is provided with a pinion, meshing with a toothed crown secured to the pulley and rotatable therewith around a second axis perpendicular to the first axis.
Owing to the invention, the maximum available load at the funicular element may be increased by acting on the gear ratio formed by the pinion and the crown. Furthermore, since the pulley rotates around an axis perpendicular to the axis of rotation of the shaft of the motor, it may be supported at both ends thereof without being cantilevered. Its axial length may thus be relatively significant, which allows winding of the funicular element over a number of revolutions allowing a relatively significant travel of the heddle.
According to advantageous, but optional aspects of the invention, such a device may incorporate one or more of the following features, considered in any technically admissible combination:
The crown is movable along the second axis and the device comprises means elastically forcing the crown toward the pinion, along the second axis. The shaft of the actuator and the axis of the pulley are concurrent. The pinion has a straight toothing and the crown has a toothing adapted to that of the pinion. The actuator is mounted in a housing, while the pulley and the crown are rotatably mounted around the second axis in a holder that is separate and separable from the housing. The device comprises several actuators mounted in a same housing, with their first respective axes parallel to each other, and several subassemblies each comprising a pulley and a crown, in a number equal to the number of actuators mounted in the housing, said subassemblies being mounted in the same holder separate and separable from the housing, with their second respective axes of rotation perpendicular to the first axes of the actuators. The crown and the pulley are rotatably mounted around a shaft aligned along the second axis and clipped on the holder. The means for elastically forcing the crown toward the pinion act between the shaft and the holder. The number of teeth of the pinion is smaller than the number of teeth of the crown. The crown is clipped and immobilized in rotation, by cooperation of shapes on the pulley.
The invention also relates to a weaving machine comprising a weaving shed device as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and other advantages thereof will appear more clearly in light of the following description of one embodiment of a weaving shed device and weaving machine according to its principle, provided solely as an example and done in reference to the appended diagrammatic drawings, in which:
FIG. 1 is a perspective view of a weaving machine of the Jacquard type according to the invention;
FIG. 2 is an exploded perspective view of a module belonging to the weaving shed device of the weaving machine of FIG. 1 , which itself is according to the invention;
FIG. 3 is an exploded perspective view of certain elements of the module of FIG. 2 ;
FIG. 4 is an exploded perspective view, from another angle, of the pulley and the crown shown in FIG. 3 ;
FIG. 5 is a perspective view of detail V in FIG. 2 , enlarged from another angle;
FIG. 6 is a perspective view along arrow VI in FIG. 5 ,
FIG. 7 is a longitudinal cross-sectional view along the shaft of a pulley subassembly, in a plane similar to plane VII in FIG. 6 , but in a central part of the holder shown in FIG. 2 , and
FIG. 8 is a front view of the part of the device shown in FIG. 6 , showing a harness card wound on the pulley.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The Jacquard-type weaving machine M shown in FIG. 1 comprises a weaving shed forming device 1 mounted on a superstructure 2 , above the beam roll 3 and the cloth beam 4 of the machine on which a fabric T being woven is wound. The device 1 comprises several modules 10 designed to control the vertical movement of harness cords 20 making up the funicular elements of a heald frame 30 of the weaving machine M, each harness cord supporting a heddle 21 equipped with an eyelet 22 for the passage of a warp yarn. Only one column of housings 10 , five harness cords 20 and five heddles 21 are shown in FIG. 1 , for clarity of the drawing. Each module 10 is positioned on a rail 5 . The shed device 1 comprises twelve rails, each of said rails being able to receive up to forty of said modules on either side. On each of the rails shown in FIG. 1 , only the first module of each rail is shown.
Each of the modules 10 comprises a housing 110 provided to receive sixteen actuators 112 in individual housings 110 A. The output shaft 114 of each of the actuators 112 is secured in rotation to a pinion 116 with a straight toothing. X 114 denotes the axis of rotation of the shaft 114 and the pinion 116 of the actuator 112 . The axes X 114 of the actuators 112 mounted in the housing 110 are parallel to each other.
Each actuator 112 is provided to drive a pulley 126 to which the upper end of a harness cord 20 is fastened. To that end, and as shown in FIG. 3 , each pulley 126 is provided with a housing 126 A for receiving and jamming an upper end (not shown) of the harness cord 20 . Alternatively, the upper end of the harness cord 20 may be overmolded in the pulley. Each pulley 126 also comprises a cylindrical portion 126 B with a circular cross-section on which a harness cord 20 can be wound whereof the end is jammed at the housing 126 A. Y 126 denotes the central axis of the portion 126 B, which is in fact the axis of rotation of the pulley 126 . L 126 denotes the axial length, measured parallel to the axis Y 126 , of the portion 126 B, i.e., the portion of the pulley 126 available for winding a harness cord.
Each pulley 126 is secured in rotation, around the axis Y 126 , with a toothed crown 124 . Each pair consisting of a crown 124 and a pulley 126 is mounted in a housing 120 A defined by a holder 120 that is attached on the housing 110 .
The holder 120 is open on the first side thereof turned toward the housing 110 , to allow the insertion of the pinion 116 in each housing 120 A. The holder 120 is also open on the second side thereof opposite the housing 110 and visible in FIG. 2 . On the second side, the holder 120 is obstructed by a cover 130 .
The parts 120 and 130 are advantageously made from a plastic material, for example an ABS polycarbonate alloy, that is particularly suitable due to its dimensional stability.
The holder 120 is reversibly mounted on the housing 110 , for example using screws (not shown). Likewise, the cover 130 is reversibly mounted on the holder 120 , for example clipped thereon.
In the mounted configuration of the module 10 , each pinion 116 of the actuator 112 is engaged with a crown 124 , which in turn is secured to a pulley 126 , while the axes of rotation X 114 and X 126 of said parts are perpendicular.
The placement of a pinion 116 and a crown 124 as intermediate parts between the actuator 112 , which generates the rotating movement of the pulley 126 , and the pulley 126 , on which the harness cord 20 is wound, allows the creation of a reduction gear. The number of teeth of the pinion 116 is smaller than the number of teeth of the crown 124 . This makes it possible to obtain a gear reduction effect of the torque obtained at the shaft 114 and which is transmitted to the pulley 126 by the reduction gear formed by the parts 116 and 124 . By acting on the ratio of the torque from the gear made up of the pinion 116 and the crown 124 , the maximum available load at the harness cord 20 may thus be adapted to the tractive forces to be generated on each harness cord 20 .
The ratio of the number of teeth of the crown 124 to the number of teeth of the pinion 116 is ⅓ in the chosen embodiment and may be comprised between ½ and ⅕.
The pinion 116 has a straight toothing and cooperates with the crown 124 , the toothing of which is adapted to that of the pinion. In practice, the toothing of the crown is of the “Cylkro” type, as known from WO-A-96/12585. In the example of the device considered an shown in FIGS. 1 to 8 , the pinion has eleven teeth with module 0 . 7 , while the crown has thirty-three teeth. The use of the straight toothing enables relatively imprecise positioning of the crown 124 along the axis X 114 . In fact, the contact conditions remain the same along a tooth of the pinion. Furthermore, the meshing does not generate any resultant on the pinion oriented along the axis X 114 . The meshing therefore has no consequence on the operating conditions of the bearings of the shaft of the actuator.
The pinion and the crown are made from polyacetal, the choice of this plastic material allowing operation without adding lubricant and guaranteeing good resistance to wear.
The crown 124 and the pulley 126 are mounted freely rotating, with the interposition of a ball bearing 122 , around a shaft 128 whereof the longitudinal axis is aligned with the axis Y 126 . Since the axes X 114 and Y 126 are perpendicular, the shaft 128 extends between two walls 1201 of the holder 120 that are vertical in FIG. 2 , while the axes X 114 and Y 126 are horizontal.
A housing 1244 of the crown 124 is provided to receive a nose 1264 of the pulley 126 . The housing 1244 and the nose 1264 have complementary and noncircular shapes. Thus, the assembly of the pulley 126 on the crown 124 ensures rotational securing with axis Y 126 of the crown and the pulley, by cooperation of shapes.
Furthermore, the pulley 126 is mounted on the crown 124 by clipping the nose 1264 of the pulley 126 in the housing 1244 , using elastically deformable tongues 1262 provided with end beaks 1266 . The beaks 1266 of the tongues 1262 are clipped in slits 1242 of the crown 124 provided to that end, on either side of the housing 1244 . This clipping of the pulley 126 on the crown 124 thereby ensures that they are translatably secured along the axis Y 126 .
A spring 123 is positioned between the shaft 128 and a wall 1201 of the holder 120 . It exerts an elastic force E 1 on said shaft oriented toward the other wall 1201 of the housing 120 A in which said shaft is received.
A pulley subassembly 129 is considered comprising a pulley 126 , a crown 124 , a ball bearing 122 , a spring 123 and a shaft 128 . Each subassembly 129 , whereof the shaft 128 is the central member, is positioned in a housing 120 A of the holder 120 .
In the normal usage configuration, one end 123 A of the spring bears against the wall 1201 of the holder 120 , while the other end 123 B is in contact with the bottom of an inner bore 1281 of the shaft 128 . The spring 123 thus exerts the elastic force E 1 on the shaft 128 . The ball bearing 122 resting on a shoulder 1286 of the shaft 128 , the shaft also exerts a force E 1 on the ball bearing 122 , which in turn exerts that force E 1 on the pulley 126 , at an inner shoulder 1268 of the pulley.
The use of an elastic forcing means such as the spring 123 makes it possible to react the meshing play between the pinion 116 and the crown 124 , along the axis Y 126 , the crown being elastically recalled toward the pinion.
It is possible to clip the ends 1282 and 1284 of the shaft 128 in housings 1204 and 1206 formed in the walls 1201 and provided to that end. The ends 1282 and 1284 have a noncircular cross-section and the housings 1204 and 1206 have geometries compatible with the placement of the ends 1282 and 1284 and with blocking thereof in rotation around the axis Y 126 . Furthermore, each housing 1204 is bordered by an elastically deformable tooth 1205 that serves as a retaining member for the end 1282 of the shaft 128 placed in the housing 1204 . This tooth retracts during the placement of the shaft 128 in the housing 1204 , after which the shaft 128 is clipped and kept in place by the tooth 1205 . A similar tooth is provided at the housing 1206 , such that the end 1284 of the shaft 128 is kept in place. Alternatively, another clipping member, or more generally retaining member, may be provided at the housings 1204 and 1206 .
The shaft 128 thus clipped is immobilized in rotation on the axis Y 126 and has a certain axial freedom. The pulley 126 , whereof the shaft is maintained at both ends by the holder 120 , is stable on its axis since it is not cantilevered. Furthermore, it rotates around the shaft 128 by means of two bearings made up on the one hand of the ball bearing 122 and on the other hand of a smooth contact area S between the inner bore of the pulley 124 and the outer cylindrical surface of the shaft 128 situated opposite the ball bearing 122 . The two bearings are located on either side of the winding portion 126 B of the harness cord 20 . It thus becomes possible to increase the length L 126 of the portion 126 B receiving the harness cord 20 , without decreasing the stability of the pulley. In practice, the length L 126 is comprised between 8 and 10 mm for a pulley 126 where of the portion 126 B has a diameter of approximately 9 mm. Under these conditions, the winding length of the harness cord 20 in the configuration of FIG. 8 has a value comprised between 270 and 290 mm.
The length L 126 is increased with respect to the axial length of the pulleys of the prior devices. This increased length makes it possible to wind a more significant harness length around the pulley. This thereby makes it possible to increase the possible travel for the heddles 21 , with respect to the known devices. In particular, the multilayer 3D weaving applications that involve forming several superimposed sheds or moving the shed along the woven layer are easily achievable.
The device reacting play along the axis Y 126 , owing to the spring 123 , previously described operates identically for the sixteen pulley subassemblies 129 contained by the holder 120 . In particular, it enables individual self-adjustment of the axial position along the axes Y 126 of the sixteen crowns 124 of the pulley subassemblies 129 mounted on the holder 120 , with respect to the sixteen pinions 116 of the actuators 112 mounted on the housing 110 , when the holder 120 is attached on the housing 110 .
According to one very advantageous aspect of the invention, the axes X 114 and Y 126 are concurrent. Thus, the distribution of the assembly tolerances of the pinions 116 and the pulley subassemblies 129 is centered on a nominal configuration where said axes are in fact secant. Thus, in the event of variation of the position of said axes, the toothings of the elements 116 and 124 remain engaged, under satisfactory meshing conditions. In other words, due to the concurrent nature of the axes X 114 and Y 126 , the reduction gear formed by the elements 116 and 124 is not particularly sensitive to positioning flaws along the axis Z perpendicular to the axes X 114 and Y 126 that are distributed on either side of the nominal configuration where said axes are in fact concurrent.
Alternatively, these axes may not be concurrent, which is possible in light of the types of toothing used.
In this way, the positioning of the crown 124 and the axis of the actuator X 114 does not need to be precise. The device is therefore compatible with an assembly without minute adjustment. The design of the device makes it possible to adapt the meshing conditions in the directions of the axes X 114 and Y 126 , as well as an allowance in direction Z.
The pulley subassemblies 129 are supported by the holder 120 , which is a separate part from the housing 110 . In this way, the sixteen subassemblies 129 and their holder 120 make up a removable functional unit that is easy to disassemble to perform maintenance operations both on the actuators 112 and the pulley subassemblies 129 . The assembly of a weaving shed device according to the invention is done by equipping each housing 110 with actuators 112 mounted in the housing 110 A. A pinion 116 is mounted on the shaft 114 of each actuator 112 before or after assembly thereof in the housing 110 . Then, the holder 120 equipped with the pulley subassemblies 129 is attached on the housing 110 . Next, the cover 130 is mounted on the holder 120 .
During the placement of the holder 120 on the housing 110 , the crowns 124 come into contact with the end bevel of the teeth of the pinions 116 , then shift along the axis of the pulley 126 shaft Y 126 against the action of the spring 123 . The spring returns the toothings to the meshing configuration, without action by the operator. Once in place, the pinions 116 and crowns 124 are in operating condition, without play and without a specific adjustment operation being necessary.
The installation of such a device also makes it possible to recondition a weaving machine from the state of the art into a weaving machine according to the invention. In practice, the transition from a simple cantilever pulley system to a gear system may include the following three steps. First, and for each actuator, the pulley is replaced by a pinion 116 . Then, the holder 120 is mounted on the housing 110 and the cover on the holder, as explained above.
Alternatively, the invention may be implemented with conical gears. These gears with concurrent axes require, to operate under optimal conditions, that the apices of the toothing cones coincide. The device for reacting the play along the axis of rotation of the pulley enables a satisfactory adjustment of the play.
The invention may also be implemented with hypoid gears, i.e., with left spiral gears. The pinions and crowns have conical teeth, but do not necessarily rotate around concurrent axes. | A shed forming device for a weaving machine includes at least one rotary electric actuator for winding, around a pulley, a funicular element controlling at least one heddle and wherein an output shaft of the actuator rotates around a first axis and wherein the output shaft is provided with a pinion meshing with a toothed crown secured to the pulley and rotatable therewith around a second axis perpendicular to the first axis. | 3 |
RELATED APPLICATIONS
The present application is a national stage entry according to 35 U.S.C. §371 of PCT application No.: PCT/EP2013/071663 filed on Oct. 16, 2013, which claims priority from Chinese application No.: 201210448864.0 filed on Nov. 9, 2012, and is incorporated herein by reference in its entirety.
TECHNICAL FIELD
Various embodiments relate to a lighting device, and an illuminating device including the lighting device.
BACKGROUND
In the Lighting devices widely used in offices, shops, homes, etc., a fastening member such as a screw or an adhesive such as glue is generally needed to fix a lighting device in a housing or on a heat sink, for example, a large number of screws are used to fix the lighting device on the heat sink to ensure a favorable thermal conduct path between the lighting device and the heat sink.
If the fastening member is used for fixing, the positional relationship between the fastening member and the lighting device is usually limited by the manufacturing requirements, for example, as there are strict requirements on the spacing between electrical components and metal screws, the use of a large number of screws on the board affects adversely the circuit layout, and causes extra difficulties on the manufacturing (the production efficiency is lowered) and product maintenance.
If only the adhesive such as glue is relied on instead of using the fastening member to fix, for example, adhering the lighting device to the heat sink using a thermal conduct adhesive, unsafe factors arise when the volume or weight of the lighting device is relatively large, e.g., in the tube-shaped Lighting device which is relatively long, the use of glue might cause accidents and mistaken adhesion caused by thermal expansion might result in potential separation/bending.
SUMMARY
Various embodiments provide a lighting device, which is fixed tightly in a housing without using an additional fastening member or adhesive, thereby reducing the number of the used components and facilitating installation and maintenance.
The lighting device includes: a housing, at least one light source, and one circuit board carrying the at least one light source, wherein the housing defines the cavity that accommodates the at least one light source and circuit board and includes the bottom carrying the circuit board, characterized in that the Lighting device further includes at least one separate mountable locking member, which is partially supported on the housing and presses the circuit board on the bottom.
In various embodiments, the manner of using the fastening member to assemble the lighting device including the circuit board and light source and the housing together is discarded, instead, a locking member with a special configuration is installed in a housing further designed with a special configuration, so as to fix the circuit board on the bottom of the housing in a pressing manner according to the geometric and mechanical principles. Therefore, various defects brought by the fixing with the fastening member and the adhesive are overcome and the number of the used components is advantageously reduced.
According to various embodiments, the housing includes the bottom and side walls extending from at least a part of the bottom, wherein the side walls support the locking member. The side wall is able to provide side supporting force for the locking member, which partially converts the supporting force to a pressing force for pressing the circuit board.
According to various embodiments, the bottom includes a first section and a second section, wherein the second section protrudes upward in relation to the first section, and the second section includes the top surface supporting the circuit board and the side surface supporting the locking member. A boss for carrying the circuit board is thereby able to be formed on the bottom, and the locking member operates with the side surface of the boss to press the circuit board on the boss.
According to various embodiments, the second section and side walls define a side gap in which the locking member is accommodated. The locking member may be an elastic clamping member, which clamps the circuit board and the second section. The locking member is able to be locked in the gap under the conditions of supporting the stress. Under such conditions, the locking member ensures to be fastened together with the housing on the one hand, and ensures to fix the circuit board on the second section on the other hand.
According various embodiments, there are two locking members which clamp two longitudinal edges of the circuit board on the bottom, respectively.
According to various embodiments, the locking member includes a first end for pressing the circuit board and a second end for pressing the second section and an intermediate portion between the first end and the second end, and the side wall supports intermediate portions. The first end and second end are able to be used on the clamping ends here; therefore, the locking member has the clamping function.
The second section may have a T-shaped cross section 65 perpendicular to the bottom and include a first part and a second part in the sequence from top to bottom, wherein the second end press the first part. Namely, the side of the second part facing the circuit board has a larger width in the cross section, while the side of the second part near the first part has a smaller width in the cross section.
The locking member may further include the outer side surface facing to the side wall, wherein the outer side surface includes a first outer side surface section against the side wall form-fit at the side of the first end, and a second outer side surface section extended obliquely in relation to the first section. The outer surface of the locking member far from the second section may have a 7-shaped curved contour in cross section. By virtue of the second outer side surface section that extends obliquely, the locking member is able to be simply inserted into the gap, and interlocked with the housing, thereby fixing the circuit board on the second section.
The locking member may further include the inner side surface facing away the side wall, wherein the inner side surface includes a first press section against the circuit board form-fit at the side of the first end, and a second press section against the second section form-fit. The inner side surface of the locking member, the end of the circuit board, and the side surface of the second section press each other, thereby to exert stress on the circuit board in the direction upright to the circuit board and fix the circuit board on the second section.
According to various embodiments, the side surface is an oblique plane in relation to the first section. Preferably, the side walls are perpendicular to the first section, and the gap has a rectangular trapezium contour in the cross section.
According to various embodiments, the side surface S 2 has a step surface. The side walls may be perpendicular to the first section, and the gap has an L-shaped contour in the cross section.
According to various embodiments, the locking member further includes a structure to lock with the circuit board, which includes at least one protruding part extended from the first end and at least one groove arranged on the circuit board.
The housing may be a heat sink. Therefore, materials strong in heat conduction, e.g. metals, may be selected to produce the housing.
In addition, various embodiments relate to an illuminating device including a cover, characterized in that the illuminating device further includes the above Lighting device, wherein the cover and Lighting device define the enclosed space that accommodates at least one light source and the circuit board carrying the at least one light source. The illuminating device may have a tubular contour. Such illuminating devices are able to be used as T5 or T8 lamps.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, like reference characters generally refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the disclosed embodiments. In the following description, various embodiments described with reference to the following drawings, in which:
FIG. 1 is a cross-sectional view of a first embodiment of the Lighting device according to the present disclosure;
FIG. 2 is a cross-sectional view of the housing in FIG. 1 ;
FIG. 3 is a 3D view of the locking member in FIG. 1 ; and
FIG. 4 is a cross-sectional view of a first embodiment of the illuminating device according to the present disclosure.
DETAILED DESCRIPTION
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the utility model may be practiced. In this regard, directional terminology, such as “top”, “bottom”, “front”, “back”, “up”, “down”, is used in reference to the orientation of the figures being described. Because components of embodiments of the present utility model can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting.
It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present utility model. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present utility model is defined by the appended claims.
FIG. 1 is a cross-sectional view of a first embodiment of the Lighting device according to the present disclosure. A Lighting device 10 includes a housing 1 and a lighting device including a light source 2 and a circuit board 3 carrying a plurality of light sources 2 . The housing 1 has a groove-shaped contour that defines a space R, and the lighting device is arranged in the middle of the bottom 5 of the housing 1 . A plurality of light sources 2 are arranged, e.g. into a linear shape; therefore, merely one light source 2 is shown in the cross section.
For the fastening of a lighting device, specially a circuit board 3 on the bottom 5 , a locking member 4 for fastening the circuit board 3 is additionally mounted in the housing 1 . By virtue of the special configuration, the locking member 4 is fastened in the housing 1 in the form of insertion, and fixes the circuit board 3 on the bottom 5 of the housing 1 by means of press according to the geometric and mechanical principles.
Now, the Lighting device 10 according to the present disclosure will be explained in detail in combination with the housing 1 and locking member 4 shown respectively in FIGS. 2 and 3 .
The housing 1 whose bottom is designed as a heat sink includes the bottom 5 and side walls 6 extending vertically from the bottom 5 at both sides. In order to form an gap 7 for accommodating the locking member 4 , the bottom 5 is specially designed to include a first section 51 that connects with side walls 6 and a second section 52 that protrudes upward in relation to the first section 51 . The second section 52 has a substantially T-shaped cross section 65 perpendicular to the bottom 5 and includes a first part 521 for carrying the circuit board 3 and a second part 522 connecting with the first section 51 . The surface of the first part 521 for carrying the circuit board 3 is a top surface S 1 , and the side surface extending from the top surface S 1 to the first section 51 is a side surface S 2 of the second section 52 . In the present embodiment, the side surface S 2 trends like a step, and is therefore able to co-define the L-shaped gap 7 with the side wall 6 .
The locking member 4 that can be accommodated easily in the gap 7 has a bending contour, and fixes the circuit board 3 on the top surface S 1 as a locking section. For the convenience of inserting the locking member 4 simply into the housing 1 , elastic materials are able to be selected to produce the locking member 4 , thereby to make the locking member endure a certain stress during the assembly.
The locking member 4 includes a first end 41 pressing the circuit board 3 and leaning on the side wall 6 and a second end 42 pressing the second section 52 specially its side wall S 2 . As the second end 42 does not need to lean on the side wall 6 , the width of the second end in the cross section is able to be designed very small, such that the second end is able to be inserted into the gap 7 and press the side surface S 2 .
An outer side surface S 3 of the locking member 4 extends from the first end 41 to the second end 42 at the side towards side wall 6 , including a first outer side surface section S 31 at the side of the first end 41 and against the side wall 6 form-fit in the upper part of the figure, and a second outer side surface section S 32 slanting refer to the first section 51 , e.g. extending at a 20° angle with the side wall 6 . Under the conditions that the elasticity of the locking member 4 is large enough, the angle between the second outer side surface section S 32 and the side wall is able to be decreased accordingly.
An inner side surface S 4 of the locking member 4 extends from the first end 41 to the second end 42 at the side towards the second section 52 , including a first press section S 41 at the side of the first end 41 and pressing the edge area of the circuit board 3 form-fit in the upper part of the figure, and a second press section S 42 between the circuit board 3 and the first section 51 pressing the second section 52 form-fit.
The side supporting force that the side wall 6 provides to the locking member 4 is passed to the circuit board 3 and the second section 52 , thereby pressing the circuit board 3 on the second section 52 by the locking member 4 . Thus, the first press section S 41 is closely pressed together with the edge area of the circuit board 3 , and exerts a vertical press F 3 and a horizontal press F 4 to the marginal area as shown in FIG. 1 . The second press section S 42 is closely pressed together with the side wall S 2 of the second section 52 , and exerts a pair of horizontal supporting forces F 1 and a vertical supporting force F 2 to the side wall S 2 as shown in FIG. 1 .
In an unshown second embodiment, the side surface of the second section is an oblique plane in relation to the first section, and is therefore able to co-define with the side wall the gap having a rectangular trapezium contour in the cross section. Under such conditions, the second press section of the locking member is designed as an oblique plane in relation to the first press section.
In addition, as shown in FIG. 3 , the locking member 4 further includes a protruding part 43 that extends from the first press section S 41 . The protruding part 43 is able to stretch into the preset groove of the circuit board 3 during assembly, thereby to ensure that the locking member 4 and the circuit board 3 are relatively fixed along the direction of extension of the circuit board.
FIG. 4 is a cross-sectional view of a first embodiment of the illuminating device according to the present disclosure. An illuminating device 100 with a tubular contour includes the Lighting device 10 shown in FIG. 1 and a cover 101 for closing the opening of the housing 1 . The cover 101 is able to be formed on the housing 1 in proper encapsulation methods such as injection molding. Or, the cover 101 may be designed as a top cover, and held form-fit between the two side walls 6 in shape by virtue of its special shape, specially the marginal areas in contact with the housing 1 .
When the light source 2 is an LED light source, such an illuminating device can be used as a remodeling lamp to replace T5 or T8 fluorescent lamps in the current technology.
While the disclosed embodiments have been particularly shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the disclosed embodiments as defined by the appended claims. The scope of the disclosed embodiments is thus indicated by the appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced. | Various embodiments may relate to a lighting device, including a housing, at least one light source, and a circuit board carrying the at least one light source. The housing defines a cavity for accommodating the at least one light source and the circuit board. The housing includes a bottom for carrying the circuit board. The lighting device further includes at least one separate mountable locking member, which is partially supported on the housing and presses the circuit board on the bottom. In addition, various embodiments further relates to an illuminating device including the lighting device. | 5 |
DEDICATORY CLAUSE
The invention described herein may be manufactured, used, and licensed by or for the Government for Governmental purposes without the payment to me of any royalties thereon.
BACKGROUND OF THE INVENTION
Bulk propellant is first cut into slabs (approximately 1 × 5 × 1/4 or 1/2 inch) and the slabs are placed into the remote controlled apparatus of the present invention to be cut into the desired "dog bone" shape for mechanical property testing.
When cutting solid propellants for such mechanical property testing it is hazardous to the operator to be in the vicinity of the cutting operation, particularly, during the standard guillotine cutting operation. There is a constant possibility of fire or explosion while cutting solid propellants.
SUMMARY OF THE INVENTION
Apparatus for cutting a slab of solid propellant into a predetermined "dog bone " shape for mechanical property testing thereof. The apparatus includes a pair of remotely controlled reciprocating air cylinders, the "bone" first of which moves a feed mechanism into engagement with the propellant slab for displacement thereof from a holder into position beneath the second cylinder. The second cylinder is disposed for downward movement of a cutting mechanism for cutting the slab into the desired "dog bone" configuration. Responsive to the cutting operation, the operator moves a lever to retract the feed device and the cutter for subsequent feeding and cutting operations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of the apparatus showing the cutter and power cylinder therefor.
FIG. 2 is a pictorial view of the apparatus showing the feed mechanism and power cylinder therefor.
FIG. 3 is a diagrammatic view illustrating both power cylinders and pneumatic lines therefor.
FIG. 4 is an elevational view of the "dog bone" configuration of the finished propellant sample.
FIG. 5 is a diagrammatic side view of the propellant stop mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, the tensile test sample making machine 10 of the present invention includes a two-way air cylinder 12 supported on a frame 14. The air cylinder 12 includes a rod 16 which has one end attached to the air cylinder piston while the other end is attached to a cutting device 18. Frame 14 includes a pair of spaced upstanding members 20 and 22, a base member 24, and an upper cross-over member 26 to which one end of the cylinder 12 is attached.
A second two-way cylinder 26 (FIG. 2) is secured to base member 24 and includes a rod 28 which has one end attached to the air cylinder piston and the other end is attached to a feed device 30. Feed device 30 includes a horizontally extending member having a substantially "L" shaped cross-sectional configuration. The upstanding portion of the "L"; 32 (FIG. 3) is attached to the piston rod and the forwardly extending portion of the "L"; 34 is longer than portion 32 and is disposed in parallel sliding relation with the upper 36 surface of base member 24.
A rectangular storage box 38 is secured to frame 14 in spaced relation with upper surface 36. The propellant slabs are stacked in storage box 38 and a weight 39 is placed on top of the stacked slabs to force them downwardly into the space 40 between the box 38 and upper surface 36. Space 40 is just slightly greater than the thickness of the propellant slab 42 (FIG. 4).
Cutting device 18 is provided with a cutting surface which cuts the rectangular propellant slab into the "dog bone" configuration shown in FIG. 4.
The diagrammatic flow diagram of FIG. 3 illustrates the pneumatic hook-up of the apparatus. As shown in FIG. 3, the forward portion 45 of the first two-way cylinder 12 is connected to a control box 44 through lines 46 and 48 which are connected by a "T" connection 50. A third line 52 from connection 50 is secured to a control valve 53. A line 54 extends from control valve 53 into the aft end 56 of a second two-way air cylinder 26.
A second control valve 58 communicates with the forward interior of cylinder 26 and a pneumatic line 60. Line 60 connects into a "T" connection 62. A second line 64 extends from the "T" connection into the aft end of air cylinder 12. The third line 66 from connection 62 extends into control box 44 which is connected to a source of air 68.
Control valves 53 and 58 are commercially available valves and are merely utilized to adjust the air flow into and out of the cylinders.
A pair of stops 70 (FIG. 1) is disposed to be raised in position as shown in FIG. 5, to hold the specimen 42 beneath cutter 18. The stops 70 are raised into their upward position responsive to engagement of an "L" shaped arm 72 (FIG. 5) with a plate 74 which is secured in biased relation to the underside of base 24. Springs 76 are disposed about a nut 78 which is secured to the underside of base 24 and extends through an opening 80 in plate 74. Springs 76 bias plate 74 upwardly. Engagement of member 72 with a downwardly extending portion 82 of plate 74 extends stops 70 upwardly. The engagement occurs responsive to forward movement of the piston in cylinder 26.
In operation, the operator loads the slabs into storage box 38 and places weight 39 on top of the slabs. One of the slabs falls into space 40 between the upper surface 36 and storage box 38. The operator moves lever 69 (FIG. 3) so that air is allowed to flow through line 46 and 52, control valve 53 and line 54 to the aft end of cylinder 26. Forward movement of the piston in cylinder 26 causes feed element 34 to engage specimen 42 for movement thereof under cutting device 18. At this time member 72 engages plate 74 for upward movement of stops 70 to retain the specimen in position. Responsive to movement of specimen 70 into position, air flows through control valve 58 lines 60, 62, and 64 behind the piston in cylinder 12 for downward movement thereof whereby the cutter engages the specimen. The operator then moves lever 69 the opposite direction to retract the pistons in both cylinders so that a slab may fall back into opening 40. Responsive to rearward movement of feed member 30, stops 70 are retracted, a new slab is dropped into space 40 and another sequence can begin. The location of plate 74 relative to member 72 permits the stop 70 to be retracted until a second slab is moved forward to displace the first slab and excess cuttings. After the first cut slab has been displaced by the second slab the pins engage the edges of the second slab for retention thereof under the cutter 18. | An air powered machine that die cuts tensile test samples of solid propelt. The machine is remotely controlled, as a safety feature, to permit safe cutting of the propellant. The machine includes a feed mechanism for feeding a propellant slab to a cutter which cuts the slab into a "dog bone" shape. | 1 |
This application is a continuation of application Ser. No. 08/266,540 filed Jun. 27, 1994 now U.S. Pat. No. 5,454,795.
FIELD OF THE INVENTION
This invention is a surgical device. In particular, it is a catheter suitable for treating a tissue target within the body, which target is accessible through the vascular system. Central to the invention is the use of stiffener ribbons, typically metallic, wound within the catheter body in such a way as to create a catheter having controllable stiffness.
BACKGROUND OF THE INVENTION
Catheters are increasingly used to access remote regions of the human body and, in doing so, delivering diagnostic or therapeutic agents to those sites. In particular, catheters which use the circulatory system as the pathway to these treatment sites are especially useful. For instance, it is commonplace to treat diseases of the circulatory system via angioplasty (PCTA) using catheters having balloons on their distal tips. It is similarly common that those catheters are used to deliver a radiopaque agent to that site prior to the PCTA procedure to view the problem prior to treatment.
Often the target which one desires to access by catheter is within a soft tissue such as the liver or the brain. The difficulty in reaching such a site must be apparent even to the casual observer. The catheter must be introduced through a large artery such as those found in the groin or the neck and be passed through ever more narrow regions of the arterial system until the catheter reaches a selected site. Often such pathways will wind back upon themselves in a multi-looped path. These catheters are fairly difficult to design and utilize in that they must be fairly stiff at their proximal end so to allow the pushing and manipulation of the catheter as it progresses through the body, and yet must be sufficiently flexible at the distal end to allow passage of the catheter tip through the loops and increasingly smaller blood vessels mentioned above and yet at the same time not cause significant trauma to the blood vessel or to the surrounding tissue. Further details on the problems and an early, but yet effective, way of designing a catheter for such a traversal may be found in U.S. Pat. No. 4,739,768, to Engelson. These catheters are designed to be used with a guidewire. A guidewire is simply a wire, typically of very sophisticated design, which is the "scout" for the catheter. The catheter fits over and slides along the guidewire as it passes through the vasculature. Said another way, the guidewire is used to select the proper path through the vasculature with the urging of the attending physician and the catheter slides along behind once the proper path is established.
There are other ways of causing a catheter to proceed through the human vasculature to a selected site, but a guidewire-aided catheter is considered to be both quite quick and somewhat more accurate than the other procedures. One such alternative procedure is the use of a flow-directed catheter. These devices often have a small balloon situated on the distal end of the catheter which may be alternatively deflated and inflated as the need to select a route for the catheter is encountered.
This invention is an adaptable one and may be used in a variety of catheter formats. The invention utilizes the concept of combining a polymeric tubing with one or one or more spirally wound ribbons to control the stiffness of the resultant catheter body. This catheter may be used in conjunction with a guidewire, but the catheter body may also be used as a flow-directed catheter with the attachment of a balloon or in combination with a specifically flexible tip, as is seen, for instance, in U.S. application Ser. No. 08/023,805 to Zenzen et al., the entirety of which is incorporated by reference.
The use of ribbons in winding a catheter body is not a novel concept. However, none have used this concept to produce a catheter which has the physical capabilities of the catheter of this invention.
Examples of previously disclosed catheters include U.S. Pat. No. 2,437,542, to Crippendorf. Crippendorf describes a "catheter-type instrument" which is typically used as a ureteral or urethral catheter. The physical design is said to be one having a distal section of greater flexibility and a proximal section of lesser flexibility. The device is made of intertwined threads of silk, cotton, or some synthetic fiber. It is made by impregnating a fabric-based tube with a stiffening medium which renders the tube stiff yet flexible. The thus-plasticized tubing is then dipped in some other medium to allow the formation of a flexible varnish of material such as a tung oil base or a phenolic resin and a suitable plasticizer. There is no indication that this device is of the flexibility required herein. Additionally, it appears to be the type which is used in some region other than in the periphery or in soft tissues of the body.
Similarly, U.S. Pat. No. 3,416,531, to Edwards, shows a catheter having braiding-edge walls. The device further has layers of other polymers such as TEFLON and the like. The strands found in the braiding in the walls appear to be threads having classic circular cross-sections. There is no suggestion of constructing a device using ribbon materials. Furthermore, the device is shown to be fairly stiff in that it is designed so that it may be bent using a fairly large handle at its proximal end. There is no suggestion to either merely wind ribbon onto a polymeric substrate to form a catheter or, in particular, to make one of such flexibility as is required herein.
U.S. Pat. No. 4,484,586 shows a method for the production of a hollow, conductive medical tubing. The conductive wires are placed in the walls of hollow tubing specifically for implantation in the human body, particularly for pacemaker leads. The tubing is made of, preferably, an annealed copper wire which has been coated with a body-compatible polymer such as a polyurethane or a silicone. The copper wire is coated and then used in a device which winds the wire into a tube. The wound substrate is then coated with another polymer to produce a tubing having spiral conducting wires in its wall.
A document showing the use of a helically wound ribbon of flexible material in a catheter is U.S. Pat. No. 4,516,972, to Samson. This device is a guiding catheter and it may be produced from one or more wound ribbons. The preferred ribbon is an aramid material known as Kevlar 49. Again, this device is a device which must be fairly stiff. It is a device which is designed to take a "set" and remain in a particular configuration as another catheter is passed through it. It must be soft enough so as not to cause substantial trauma, but it is certainly not for use as a guidewire. It would not meet the flexibility criteria required of the inventive catheter described herein.
U.S. Pat. No. 4,806,182, to Rydell et al., shows a device using stainless steel braid imbedded in its wall and an inner layer of polyfluorocarbon. The process also described therein is a wax to laminate the polyfluorocarbon to a polyurethane inner liner so as prevent delamination.
U.S. Pat. No. 4,832,681, to Lenck, shows a method and apparatus for artificial fertilization. The device itself is a long portion of tubing which, depending upon its specific materials of construction, may be made somewhat stiffer by the addition of spiral reinforcement comprising stainless steel wire.
Another catheter showing the use of braided wire is shown in U.S. Pat. No. 5,037,404, to Gold et al. Mention is made in Gold et al of the concept of varying the pitch angle between wound strands so to result in a device having differing flexibilities at differing portions of the device. The differing flexibilities are caused by the difference in pitch angle. No mention is made of the use of ribbon, nor is any specific mention made of the particular uses to which the Gold et al. device may be placed.
U.S. Pat. No. 5,069,674 shows a small diameter epidural catheter which is flexible and kink-resistant when flexed. The wall has a composite structure including a helical coil, typically stainless steel or the like, a tubular sheath typically of a polymer, and a safety wire which is spiraled about the coil and is often in the shape of a ribbon.
U.S. Pat. No. 5,176,660 shows the production of catheters having reinforcing strands in their sheath wall. The metallic strands are wound throughout the tubular sheath in a helical crossing pattern so to produce a substantially stronger sheath. The reinforcing filaments are used to increase the longitudinal stiffness of the catheter for good "pushability". The device appears to be quite strong and is wound at a tension of about 250,000 lb./in. 2 or more. The flat strands themselves are said to have a width of between 0.006 and 0.020 inches and a thickness of 0.0015 and 0.004 inches. There is no suggestion to use these concepts in devices having the flexibility and other configurations described below.
U.S. Pat. No. 5,178,158, to de Toledo, shows a device which is a convertible wire having use either as a guidewire or as a catheter. The coil appears to be a ribbon which forms an internal passage through the coil/catheter device. No interior coating is applied.
U.S. Pat. No. 5,217,482 shows a balloon catheter having a stainless steel hypotube catheter shaft and a distal balloon. Certain sections of the device shown in the patent use a spiral ribbon of stainless steel secured to the outer sleeve by a suitable adhesive to act as a transition section from a section of very high stiffness to a section of comparatively low stiffness.
None of these devices are catheters which have the critical bend diameter required herein, nor do they have the compression strength, or flexibility of the present invention.
SUMMARY OF THE INVENTION
This invention is a catheter section made up, desirably, of an inner tubing liner, one or more spirally wound stiffener ribbons, and an outer covering. The inner tubing liner, when used, typically is a polymeric section of tubing which may be a thermoplastic and is miscible upon heating with the material found in the outer covering. The inner layer may be a thermosetting material which adheres to the outer material or which may be adhesively bound to the outer material. In any event, the two or more polymeric layers are to hold the spirally wound stiffener ribbons in place in the catheter assembly.
The stiffener ribbon may be wound onto the inner tubing liner in a number of different ways. It may be, in its most basic form, a single strand of ribbon wound in a single direction. It may a number of ribbons of differing sizes and compositions wound each way around the tubing liner. The ribbons are typically metallic but may be of other materials.
The various catheter sections may be formed into an integral catheter assembly. Wise choices of materials permit the catheter to be of a smaller overall diameter with a superior critical diameter. The catheter may be designed to integrate lubricious materials into the base design of a particular catheter product without adding extraneous thickness and stiffness. The catheter may be wholly constructed of materials which are stable to radioactive sterilization procedures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows, in side view, a typical three section catheter.
FIG. 2 shows, in magnification, a section of the inner portion of one inventive section of this catheter.
FIG. 3 shows, in magnification, a section of the inner portion of this catheter.
FIGS. 4, 5, and 6 show fragmentary, cross sectional views of various configurations of the inner sections of multi-section catheters made according to this invention.
FIG. 7 shows, in cross-section, a typical catheter section made according to this invention.
FIG. 8 shows a fragmentary cross-sectional view of a catheter section made according to this invention.
FIGS. 9A and 9B show details of the method of testing the "critical bend diameter" of this invention.
FIGS. 10 and 11 show highly desirable embodiments, in fractional cross-section, of multi-section catheters made according to this invention.
DESCRIPTION OF THE INVENTION
This invention is a kink-resistant catheter section or catheter. It is a composite device having at least one section including a helically wound ribbon stiffener coaxially incorporated into that section or sections. The catheter is configured so that at least the distal portion of the catheter has a critical bend diameter of no more than 3.5 mm, preferably no more than 2.5 mm, and most preferably no more than 1.5 mm. Additionally, that section desirably has a lateral stiffness, such as would be measured by a Tinius-Olsen Stiffness Tester, of at least 6,500° of deflection/inch-pound (measured at 20°-30° of deflection, 0.005 lb, over a 0.25" span), preferably 7,500° of deflection/inch-pound, and most preferably 9,500° of deflection/inch-pound. We have additionally found that the radial compression strength of the section is quite high as compared to other distal sections found on comparable catheter distal sections.
A typical multi-section catheter (100) which may incorporate the concepts of this invention is shown in FIG. 1. Such a catheter is described in more detail in U.S. Pat. No. 4,739,768, to Engelson, (the entirety of which is incorporated by reference) and is suitable for neurological and peripheral vascular applications. Clearly, then, it is also suitable for less demanding service such as might be encountered in access and treatment of the heart. One difficulty which has arisen as higher demands for length have been placed on these catheters is that the diameter of the distal section necessarily becomes smaller and smaller. This is so since the longer catheters must reach ever more smaller vascular areas. This smaller diameter requires a concomitant thinning of the wall section. The thinner section walls may kink or ripple when actively pushed along the guidewire or when vasoocclusive devices are pushed through the catheter's lumen. The typical configuration shown in FIG. 1 has a distal section (102) having significant flexibility, an intermediate section (104) which is typically less flexible, and a long proximal section (106) which in turn is least flexible. The distal section (102) is flexible and soft to allow deep penetration of the extraordinary convolutions of the neurological vasculature without trauma. Various known and necessary accessories to the catheter assembly, e.g., one or more radiopaque bands (108) at the distal region to allow viewing of the position of the distal region under fluoroscopy and a luer assembly (110) for guidewire (112) and fluids access, are also shown in FIG. 1. The typical dimensions of this catheter are:
Overall length: 60-200 cm
Proximal section (106): 60-150 cm
Intermediate Section (104): 20-50 cm
Distal Section (102): 2.5-30 cm
Obviously, these dimensions are not particularly critical to this invention and are selected as a function of the malady treated and its site within the body. However, as will be discussed below, use of the spiral wound ribbon permits the walls of the catheter to be somewhat thinner with no diminution of performance, e.g., crush strength or flexibility, or indeed, an improvement in performance.
FIG. 2 shows a magnified section of a catheter body or section (200) showing the most basic aspects of one variation of the invention. As shown there, the catheter body or section has an inner tubing member (202) and a helically wound ribbon (204). The inner tubing member (202) may, depending on the section of the catheter, be of any of a variety of polymers, variously stiff or flexible. For instance, if the section (200) is used as a proximal section, the inner tubing (202) may be a polyimide, polymides such as the Nylons, high density polyethylene (HDPE), polypropylene, polyvinylchloride, various fluoropolymers (for instance: PTFE, FEP, vinylidene fluoride, mixtures, alloys, copolymers, block copolymers, etc.), polysulfones or the like. Blends, alloys, mixtures, copolymers, block copolymers, of these materials are also suitable, if desired.
If a more flexible section is required, the inner tubing member (202) may be a polyurethane, low density polyethylene (LDPE), polyvinylchloride, THV, etc. and other polymers of suitable softness or modulus of elasticity.
We have also found that this catheter design allows us to use in the distal portion of the catheter, thin-walled tubing of inherently more slippery polymers, such as PTFE and FEP and their mixtures, which have the benefit of being lubricious but otherwise would have been used in a somewhat greater thickness. Clearly, greater thickness tubing of these polymers results in the tubing being somewhat stiffer. The wall thickness of the inner tubing liner (202) may be as thin as 0.5 mil and as thick as 10 mil, depending upon catheter usage, portion of the catheter chosen, polymer choice, and the style of catheter. Typical choices for inner tubing liner polymers would be:
______________________________________ Example Wall ThicknessCatheter Section Polymer (mil)______________________________________Distal Polyethylenes 0.5-3 Fluoropolymer 0.5-3 s 0.5-3 PolyurethaneIntermediate Polyethylenes 1-4 Fluoropolymer 1-4 s 1-4 polyolefin 1-4 blends PolypropyleneProximal LDPE/HDPE 1-4 Polypropylene 1-4 Fluoropolymer 1-4 s 1-4 Polyimide______________________________________
These dimensions are obviously only ranges and each catheter variation must be carefully designed for the specific purpose to which it is placed.
Preferred combinations of polymers for catheter configurations will also be discussed below. It should also be noted at this point that each of the polymers discussed herein may be used in conjunction with radiopaque material such as barium sulfate, bismuth trioxide, bismuth carbonate, powdered tungsten, powdered tantalum, or the like so that the location of the various pieces of tubing may be radiographically visualized within the vessel.
The spiral wound ribbon (204) shown in FIG. 2 may also be of a variety of different materials. Although metallic ribbons are preferred, because of their strength-to-weight ratios, fibrous materials (both synthetic and natural) may also be used. Preferred, because of cost, strength, and ready availability are stainless steels (308, 304, 318, etc.) and tungsten alloys. Also acceptable, but with a penalty variously in strength, density, and ductility, are precious metals such as gold, platinum, palladium, rhodium and the like, as well as alloys of these metals. Alloys of many of these precious metals with, for instance, tungsten, have lower ductility than the neat precious metal.
The class of alloys known as super-elastic alloys is also a desirable selection, although the processability of these alloys into small ribbons is not routine. Preferred super-elastic alloys include the class of materials known as nitinol--alloys discovered by the U.S. Navy Ordnance Laboratory. These materials are discussed at length in U.S. Pat. Nos. 3,174,851 to Buehler et al., 3,351,463 to Rozner et al., and 3,753,700 to Harrison et al. These alloys are not readily commercially available in the small ribbons required by the invention described here, but for very high performance catheters are excellent choices.
Metallic ribbons (204) that are suitable for use in this invention are desirably between 0.75 mil and 1.5 mil in thickness and 2.5 mil and 8.0 mil in width. For superelastic alloys, particularly nitinol, the thickness and width may be somewhat finer, e.g., down to 0.5 mil. and 1.0 mil., respectively. Currently preferred, based on strength, cost and availability are stainless steel ribbons of 1 mil.×3 mil., 2 mil.×6 mil., and 2 mil.×8 mil.
Suitable non-metallic ribbons include those made of polyaramids (e.g., KEVLAR), carbon fibers, and lower performance polymers such as Dacron and the Nylons. Acceptable natural fibers include silk and cotton. It should be observed that the preferred manner of using non-metallic ribbons in this invention is in combination with metallic ribbons to allow "tuning" of the stiffness of the resulting composite or as an opposite "handed" ribbon in the composite to lessen the tendency of the metallic ribbon to unwind and hence create bumps or constructions in the catheter lumen.
Returning to FIG. 2, the stiffener ribbon (204) may be simply wound onto the inner tubing liner (202). Depending upon the choice of materials for inner tubing liner (202), the stiffener ribbon (204) may be applied with an adhesive. The adhesive is used primarily to cause the outer cover (discussed below) to adhere to the inner tubing liner (202). We prefer to choose polymers for the components of the catheter which inherently adhere to each other, e.g., certain polyethylenes and polyimides, or thermoplastics, which are miscible with each other upon appropriate heating, e.g., PEBAX and polyurethanes. When we construct a catheter section using only the materials found in the respective tubing sections, or using a third material to improve the miscibility of the materials found in the respective liners and cover, we refer to that construction as being "binderless." If an adhesive is used to promote the adherence and outer layer to an inner layer, that would not be "binderless."
Thermoplastics which are inherently adherent to each other or are miscible with each other are preferred in the intermediate and distal areas of the catheter since the noted adhesives may then be omitted and the various stiffener ribbons held in place by the junction of the inner tubing liner (202) and the outer cover (not shown in this Figure).
The wound inner sector shown in FIG. 2 incorporates a helically wound stiffener ribbon (204) wound in one direction or "hand". FIG. 3 shows a second stiffener ribbon (206) wound in a second direction or "handedness" around both the first stiffener ribbon (204) and the inner tubing liner (202).
For economies of production, it is desirable to "gang-wind" the ribbon stiffeners onto the inner tubing liner. That is to say, for instance, that a catheter having a primary or first stiffener ribbon (204) with a spacing of twelve turns per inch can be produced by turning the catheter tubing twelve times and wrapping a single ribbon about it or by turning the catheter tubing six times and wrapping a pair of stiffener ribbons spaced apart so to produce a device appearing to have twelve turns of ribbon thereon. Similarly, the inner tubing can be turned four times with a gang-wind of three ribbons, etc. As will be discussed below, none of the wound ribbons of necessity must be of a consistent size. Each stiffener ribbon on each section of the catheter assembly may be of a different width and thickness.
A further aspect of this invention is shown in FIG. 4. The catheter (210) has three discrete sections: a proximal section (212), an intermediate section (214) and a distal section (216). This catheter (210) is analogous in overall function to that shown in FIG. 1. In particular, the proximal section (212) of the catheter is stiffest in that the number of stiffener ribbons (218) are wound onto the tubular substrate is densest. The distal portion (216) is wound to the other extreme in that the number of stiffener ribbons (218) is least dense. The intermediate section (214) is wound with stiffener ribbons to a density intermediate between the two adjacent sections. As has been noted elsewhere, although the majority of instances noted herein discuss three-section catheters, the invention is not so limited. The inventive catheters may have fewer or may have more sections depending upon the ultimate use to which the catheter is placed.
The FIG. 4 catheter sections are shown using stiffener ribbons in each section of the same size. The various stiffener ribbons are of the same size in each direction of wind as well. The density of turns is one way in which to control the overall stiffness of the catheter section.
Another method for controlling stiffness is shown in FIG. 5. As was the case with the catheter shown in FIG. 4, a three piece catheter (220) is shown. In this instance, however, the manner of controlling the stiffness is different. In this embodiment, the width of the respective stiffener ribbons is varied to acquire the specific desired stiffness. For instance, in catheter assembly (220), the proximal portion (222) uses comparatively wide stiffener ribbons (228) shown wound in both directions. Intermediate section (224) utilizes narrower stiffener ribbons (230) and distal section (226) uses the narrowest stiffener ribbons (232).
Although, again, each section is portrayed as having ribbons of equal size, wound in each direction, such is obviously not a requirement of the invention.
The width of the ribbons may be chosen in such a way that different sizes are wound in different directions or multiple sizes of stiffener ribbon may be gang-wound in the same direction or, obviously, a combination of these themes are also appropriate.
FIG. 6 shows a three-part catheter to (240) also having an exempletive three-part construction: proximal section (242), intermediate section (244) and distal section (246). In this configuration, the proximal section (242) utilizes both wide stiffener ribbons (248) and narrow stiffener ribbons (250) in one wind direction and only narrow stiffener ribbons (252) in the other wind direction. The intermediate sector (244) uses the same collection of ribbons in each wind direction: specifically, two narrow ribbons (254) and a single wide ribbon (256). The distal section (246) utilizes but a single width of ribbon (258) in each wind direction. This drawing depicts the wide variation in "tuning," the stiffness of the catheter sections for particular purposes by use of varied spacing of the stiffener ribbon winding, the use of various width ribbons, as well as the use of combinations of ribbon width.
Once the stiffener ribbon is wound onto the inner tubing liner, an outer covering must then be applied.
FIG. 7 shows, in cross-section, a section of (270) of catheter having an inner tubing liner (272), a stiffener ribbon (274), and an outer cover (276). The outer cover or layer may be applied in a variety of ways. As noted above, the preferred way is to shrink an appropriate tubing onto the stiffener ribbon and continue to shrink the tubing in such a way that it fills the interstices between windings of the stiffener ribbon (274) as is shown in FIG. 7. This allows the outer covering (276) directly to contact the inner tubing liner (272). Even more desirably, the outer tubing (276) should be further heated to allow mixing of the outer covering (276) with the inner tubing liner (272) at their interface so as to form a strong integral catheter section (270). If the two polymer layers are mixed at this interface, so much the better for the strength of the bond.
It should be apparent that the outer layer (276) may also be applied by dipping the inner tubing layer (272)/stiffener ribbon (274) into a molten polymer bath or into a polymer dissolved in a solid or into a suspension or latex comprising the outer cover polymer. Obviously, the cover may be placed on the catheter by spraying or otherwise applying the material. Included in such a class are the polyurethanes, polysilicones, polyvinylpyrrolidone, etc.
The catheter and catheter sections of this invention may be coated or otherwise treated to increase their lubricity.
FIG. 8 shows another variation of the inventive catheter body in which the inner polymeric layer is eliminated. The section is quite simple in construction. Specifically, an outer layer of a polymeric material (280) is placed over a previously wound coil (282). These outer layers may preferably be made of a heat shrinkable tubing having a thin wall thickness. Polyethylenes, polyurethanes, polyvinylchloride, polyfluoroethylenes, and blends or copolymers containing such polymers (e.g., THV) are especially preferred.
The FIG. 8 variation, when used with a coil (282) wire or ribbon having a pitch selected to provide spacing between adjacent turns of the coil, is especially useful as a distal or midsection of a catheter in that it is quite flexible, retains kink resistance, and is quite easy to construct.
As was noted above, the most distal portion of the distal section of this catheter (and preferably other sections as well) have a critical bend diameter of no more than 3.5 mm, preferably no more than 2.5 mm, and most preferably no more than 1.5 mm. Additionally, that section desirably has a lateral stiffness, such as would be measured by a Tinius-Olsen. Stiffness Tester, of at least 6,500° of deflection/inch-pound (measured at 20°-30° of deflection, 0.005 lb, over a 0.25" span), preferably 7,500° of deflection/inch-pound, and most preferably 9,500° of deflection/inch-pound.
The test we utilize for critical bend diameter determination uses a test shown schematically in FIGS. 9A and 9B.
In general, as shown in FIG. 9A, a catheter section (300) is placed between two plates (desirably of plastic or glass or the like for visibility) and often with an optional peg (302) to hold the catheter section (300) loop in place. The ends of the catheter are then pulled until a kink appears in the body of the catheter. Alternatively, the ratio of the outer diameters (major diameter:minor diameter) as measured at apex (304) reaches a value of 1.5. FIG. 9B shows the cross section of the catheter sector at (304) and further shows the manner in which the major diameter and the minor diameter are measured. These two methods provide comparable results although the latter method is more repeatable.
Many times herein, we refer to the "region" section of the catheter. Where the context permits, by "region" we mean within 15% of the point specified. For instance, "the distal region of the distal section" would refer to the most distal 15% in length of the distal section.
Two highly desirable catheter designs are shown in FIGS. 10 and 11, in fragmentary cross-section. In particular, FIG. 10 shows a catheter having two sections of different stiffness. The proximal section (320) is made up of an inner tubing liner (322) of polyimide, a spiral wound stiffener ribbon (324) of 1 mil.×3 mil. stainless steel, and an outer covering (326) of shrink wrap FEP-vinylidene fluoride (THV-200). The distal section (328) shares the same outer covering (326) but also has an inner tubing liner (330) of FEP-vinylidene fluoride (THV-200). It may be observed that the spacing between the winds of stiffener ribbon (326) is quite different in the two sections, The proximal section has a twelve turn per inch spacing but the distal section has a wind spacing of only four turns per inch.
FIG. 11 shows a three flexibility sector catheter (340) with a proximal section (342), an intermediate section (344), and a distal section (346). The proximal section is made up of an inner liner (348) of FEP; a spiral-wound 1×3 millimeter stainless steel ribbon (350) of twelve turns per inch spacing is turned each way on the inner liner; and an outer layer of FEP-vinylidene fluoride (THV-500).
The intermediate section (344) includes an extension of the proximal inner liner (348) found in the proximal section (342) and an outer distal section (354). The outer distal covering (354) may also be of FEP (but of a somewhat softer makeup than the proximal inner liner (348)) but preferably is of a FEP-vinylidene fluoride such as THV-200. The FEP and FEP-vinylidene copolymer are miscible when heated. The wind-spacing in this section has been spread out to a spacing of nine turns per inch.
Finally, the distal section (346) is made up of an extension of the outer distal section (354) and an inner distal tubing (356). In this case, the inner distal section is of the same material as that of the outer distal section (356). The wind-spacing in this section has been spread out to a spacing of six turns per inch.
This invention has been described and specific examples of the invention have portrayed. The use of those specifics is not intended to limit the invention in any way. Additionally, to the extent that there are variations of the invention which are within the spirit of the disclosure and yet are equivalent to the inventions found in the claims, it is our intent that this patent cover those variations as well. | This invention is a surgical device. In particular, it is a catheter suitable for treating a tissue target within the body, which target is accessible through the vascular system. Central to the invention is the use of stiffener ribbons, typically metallic, wound within the catheter body in such a way as to create a catheter having controllable stiffness. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a method for fracturing the earth from a wellbore by over pressuring a fluid(s) and/or gases inside a wellbore under conditions of resonance.
BRIEF DESCRIPTION OF PRIOR ART
Fracturing the earth from a wellbore is a known technique for enhancing oil production and recovery from an oil bearing bed. A variety of methods have been proposed to create both short and long fractures near a wellbore. One of method is described and claimed in U.S. Pat. No. 5,617,921 by Schmidt et al., herein incorporated by reference, wherein a method for initiating and/or extending a fracture in an earth's formation from a well penetrating the formation utilizing a source of high pressure fracturing fluid disposed on the earth's surface which is released to flow into and through the well at a predetermined time to initiate and/or extend the fracture. However, this method requires a significant amount of energy and to have a relatively large diameter tubing string in which to hold a sufficient charge of pressured gas to provide an adequate fracture fluid pressure and flow characteristics.
The use of high pressured gas or other pressured fluid(s) in a wellbore to clean perforations and/or create fractures has been described in U.S. Pat. Nos. 5,669,448 and 5,131,472, herein incorporated by reference. These references disclose a method of stimulating a well by suddenly applying pressure to the formation in excess of the fracture gradient pressure and thereafter pumping fluid into the well before the pressure declines below the fracture gradient pressure. In addition, there are other more expensive means of injecting treatment liquids that have been proposed. One such type of approach is to place the treatment liquid in the well and ignite a gas generating propellant in the production string, as shown in U.S. Pat. Nos. 6,138,753; 5,443,123; 5,101,900; 4,936,385 and 2,740,478, herein incorporated by reference. Of more general interest is the disclosure in U.S. Pat. No. 3,029,732, herein incorporated by reference,
While there have been a variety of methods proposed for creating hydraulic fractures around the wellbore, there remains a need for an effective, high-pressure method which creates a pattern of fractures extending from all perforations into the formation in particular with the required parameters of fractures.
SUMMARY OF THE INVENTION
Accordingly, a primary object of the present invention is to provide a method for enhancing of forming at least one fracture having a required width r and length L in the formation surrounding a wellbore in the regime of resonance by means of applying a vibrations to the formation which is undergoing a pressurizing process when a formation pressure exceeds the fracture gradient pressure of the formation as a result of pumping in of a fracturing fluid into a wellbore and farther into the formation through the perforations. In accordance with the invention, the method includes the steps of providing the pressurized fracturing fluid via tubing into a device for generating vibrations attached to the end of tubing inside the wellbore in the vicinity of the perforations and consisting of an elongated cylinder and plunger connected to a pumping means, and reciprocating upward and downward said plunger inside the elongated cylinder such that movement of plunger compresses liquid inside said tubing and generating the repetitive pulses of vibrations every time when said plunger exits out of a top of said elongated cylinder on upward movement of said plunger due to quick release of compressed liquid into said wellbore thereby generating vibrations having an amplitude varying between 15-35 MPa on a resonant frequency f r in accordance with following expression:
f r = c 2 π r 1.2 HL ( r + W ) ,
where f r is the frequency of resonance, c is a speed of sound in the fracturing fluid, π equals 3.1415, r is the required width of fracture, H is a combined thickness of a casing and a cement bond surrounding the casing, W is a length of a casing arch between two neighboring perforations, L is the required length of fracture.
It is another object of the present invention to provide the method for enhancing of forming at least one fracture having a required width r and length L in the formation surrounding a wellbore in the regime of resonance in which the repetitive pulses of vibrations provide with the rate from 10 times per hour to 20 times per minute.
It is another object of the present invention to provide the method for enhancing of forming at least one fracture having a required width r and length L in the formation surrounding a wellbore in the regime of resonance in which for known formation pore pressure P p , formation density ρ, depth of perforations H and formation Poisson's ratio ν the amplitude of the repetitive pulses of vibrations P a is defined by the following expression:
P a = 1 - v ( 1 + v ) ( 1 - 2 v ) ( 1.8 P p - 0.9 ρ gH )
where g is a gravity acceleration.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic illustration of the wellbore in which the method and the apparatus of the present invention is employed.
FIG. 2 is a cross-sectional top view of the wellbore and the formation with the fractures.
FIG. 3 is a measured dynamometer diagram of repetitive pulses of load provided by device for generating vibrations.
FIG. 4 is a waveform and spectrum of a single burst/pulse provided by device for generating vibrations.
DETAILED DESCRIPTION
Referring to FIG. 1 and FIG. 2 , there is shown the wellbore 1 having perforations 5 and fractures 6 . FIG. 1 shows a general arrangement of a device for generating vibrations and procedure using the vibrations, the flow line 11 at the surface supplying the pressurized fracturing fluid from tank 13 via pump 12 into wellbore 1 , the check valve 10 which is closed when the pressure of fracturing fluid inside the tubing 2 is greater than the one in flow line 11 thereby preventing flow of fracturing fluid from the tubing 2 back into the flow line 11 , the tubing string 2 connected to flow line 11 and extending downwardly into the wellbore 1 , a device for generating vibrations consisting of the elongated cylinder 3 connected with the bottom of tubing string 2 at the upper end and having the opening 8 to wellbore 1 , the plunger 4 having the taper 16 movably arranged within the elongated cylinder 3 to move within said elongated cylinder 3 , the pumping means 7 (for instance, sucker rods which, in turn, are connected to pumping unit) connected with the plunger 4 for moving the plunger 4 within the elongated cylinder 3 and compressing the fracturing fluid contained between the check valve 10 inside the flow line 11 and plunger 4 inside the elongated cylinder 3 and discharging the compressed fracturing fluid into the wellbore 1 via the opening 8 when plunger 4 exits out of the elongated cylinder 3 on every upstroke of the pumping means 7 to generate the vibrations due to the creating a periodic vortices in accordance with well known phenomenon of an auto-oscillations discovered by V. Strouhal in 19 th century. A lubricator 9 accommodates a pumping means 7 to prevent the leakage of the compressed fracturing fluid from the tubing string 2 and flow line 11 at the surface. More details about phenomenon of auto-oscillations could be found for example in the articles: Sobey, Ian J. (1982). “Oscillatory flows at intermediate Strouhal number in asymmetry channels”. Journal of Fluid Mechanics, N. 125: 359-373, herein incorporated by reference, and Sakamoto, H.; Haniu, H. (1990). “A study on vortex shedding from spheres in uniform flow”. Journal of Fluids Engineering, N 112 (December 1992): 386-392, herein incorporated by reference.
The generation of vibrations is repetitive and occurs in the form of bursts or so called hydro-impact waves/pulses at the moment when plunger 4 exits out of the elongated cylinder 3 due to the upward motion of the pumping means 7 . The pumping means 7 provide a reciprocating upward and downward movements of the plunger 4 inside the elongated cylinder 3 . The number or rate of reciprocating movements may vary from a few per hour to a dozens per minute depending on the particular fracturing operation. FIG. 3 shows the typical measured dynamometer diagram of repetitive load pulses created by device for generating vibrations. The amplitude of bursts/pulses may vary between 15-35 MPa depending on the type of formation undergoing fracturing. For relatively soft formation like, for instance, the unconsolidated sandstones this amplitude should be lower compared to hard formation like the deep shales. In case the characteristics of formation are known, i.e. the formation pore pressure P p , the formation density ρ, the depth of perforations H and the formation Poisson's ratio ν the amplitude of the repetitive pulses of vibrations P a is defined by the following expression:
P a = 1 - v ( 1 + v ) ( 1 - 2 v ) ( 1.8 P p - 0.9 ρ gH ) ,
where g is a gravity acceleration. In particular, for formation pore pressure P a , the formation density ρ, the gravity acceleration g, the depth of formation H and Poisson's ratio ν accounting for 45 MPa, 2300 kg/m 3 , 9.81 m/s 2 , 3000 m and 0.25, correspondingly, the amplitude of the repetitive pulses of vibrations P a accounts for 24 MPa.
The typical measured waveform of a single burst and corresponding spectrum are shown on FIG. 4 . The diagram/waveform on the left part of FIG. 4 shows the signal from device for generating vibrations recorded by a geophone and two geophones, namely, horizontal and vertical ones in the offset well located on the distance of 1385 feet from the well wherein the device for generating vibrations was installed. The duration of the bursts accounts for 40-100 milliseconds depending on pressure of the compressed fracturing fluid between the plunger 4 and the check valve 10 . A main or resonance frequency of generated vibrations can be “moved” along the frequency axis to the left or right on the spectrum diagram by providing the device for generating vibrations having an ability to create vibrations on a particular resonant frequency, i.e. the frequency matching so called eigen frequency of fractures with predetermined or required width r and length L. As it is seen from FIG. 4 the amplitude of the resonant frequency is by about 30-50 times higher compared with the rest of frequencies in spectrum (the units on vertical axis are in decibels). The check valve 10 installed on a flow line 11 could have a simple design having a seat with round hole in the center of said seat and a ball having bigger diameter and matching said hole in such manner that when the pressure of fracturing fluid in front of ball is greater than behind the one the ball closes said round hole of said seat thereby preventing any backward flow of fracturing from flow line 11 into the tank 13 . It should be noted that valve 18 during fracturing has to be either closed or at least one standard packer (not shown) is installed between tubing 2 and casing 15 above the perforations 5 . FIG. 2 shows the cross-sectional top view of the wellbore 1 , a casing 15 , cement bond 17 , and the formation with the perforations 5 and the fractures 6 . The eigen, natural or resonant frequency of such fractures (or slots in acoustics) is determined by the following formulae:
f r = c 2 π r 1.2 HL ( r + W ) ,
where f r is the frequency of resonance, c is a speed of sound in the fracturing fluid, π equals 3.1415, r is the required width of fracture 6 , H is the combined thickness of the casing 15 and the cement bond 17 surrounding the casing, L is the required length of fracture 6 , W is a length of the casing arch between two neighboring perforations 5 . In particularly, for fracturing event shown on FIG. 3 (four fractures 6 ) W=πD/4, where D is the diameter of the casing 15 . Thus, in order to get the fracture(s) 6 with particular parameters, i.e. the required width r and length L, the affecting vibrations have to be supplied on corresponding resonant frequency. For instance for the following parameters: r=0.02 m, H=0.05 m, L=100 m, W=0.13 m (corresponds to 7.0 inch casing and four fractures), c=1600 msec (corresponds to 70 MPa hydrostatic pressure under 20° C. temperature in wellbore) the resonant frequency equals 38 Hz. It should be noted that under conditions of resonance the fractures 6 will have predetermined, required width r and length L. It's important from the point of view of fracturing process when in case of too wide width r the excessive usage of proppant could be prohibitively expensive, and the fracture having too long length L can reach the highly water saturated sublayer of formation leading to the production of excessive portion of water instead of oil or gas from fractured well.
As an alternative source of the said vortices generating vibrations on resonant frequency, for instance, can be used the devices described in U.S. Pat. No. 8,459,351, herein incorporated by reference.
While in accordance with the provisions of the Patent Statutes the preferred forms and the embodiments of the invention have been illustrated and described, it will be apparent to those of ordinary skill in the art various changes and modifications may be made without deviating from the inventive concepts set forth above. | The method for enhancing of forming at least one fracture having a required width r and length L in the formation surrounding fracturing around a wellbore in the regime of resonance by means of applying vibrations to the formation which is undergoing pressurizing exceeding the fracture gradient pressure of the formation. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to bending machines and equipment for bending lengths of pipe used in oil, gas, water, and other types of transmission pipelines and specifically to bending dies used in pipe bending machines.
[0003] 2. Background of the Invention
[0004] Conventional dies used in pipe bending machines include half-cylindrical geometries machined so as to have a curve along their length. The radius of curvature of these dies depends upon the diameter of the pipe and have been determined over time. Such radii of curvature as well as known information relating to the recommended degrees of bend are known in the art and can be found on various tables.
[0005] A substantial defect inherent in conventional dies is the fact that in practice, the bending force applied is concentrated at one point along the rigid die thereby creating the effect of bending the pipe over a transverse cylinder as opposed to a radius of curvature. The result being the creation of a hot spot on the pipe where the bend occurs. At this spot the pipe weakens from being stretched and also tends to oval in cross-section.
[0006] If the bending machine operator is not careful and attentive and pulls too much of a bend, the pipe is known to wrinkle at this hot spot rendering it unusable. The wrinkled section must then be cut out creating waste of very expensive pipe material. As a matter of caution, recommended degrees of bend are small using only a small stroke of the hydraulic cylinders of the bending apparatus. Substantial bends over shorter lengths of pipe result. A need, therefore, exists for a die assembly which includes a flexible die portion to distribute the bending force over a longer length of the pipe thereby creating a uniform bend without hot spots and their attendant ovalization or weakening of the pipe wall. A further need exists for such a die which will further allow greater degrees of bend over longer segments of pipe.
SUMMARY OF THE INVENTION
[0007] The die assembly of the present invention includes three major components, an exterior housing, a flexible die, and an eggcrate assembly. The exterior housing encompasses the flexible die and eggcrate assembly and pins into conventional bending machines.
[0008] The flexible die includes a plurality of plate segments positioned along a pair of tie rods. Each plate segment is narrow in width and is hung on the tie rods so as to be free floating thereon. The plate segments are arranged so as to provide a space between adjacent plate segments such that flex of the tie rods causes the plate segments to converge on the end in the direction of the flex and diverge (accordian) in the direction opposite the flex.
[0009] The eggcrate assembly provides a support for a plurality of spring plates. Each spring plate has a radius of curvature consistent with the amount of bend desired in the pipe. During the bending process, a force is applied by the stiffback of the bending machine against the pipe. The pipe in turn forces the flexible die in contact with the spring plates of the eggcrate assembly. Since each plate segment is independent and free floating on the tie rods, the bending force exerted by the die to the pipe is distributed among the plate segments thereby creating a uniform bend. A plurality of liner bars may be positioned between the plate segments and the pipe to further distribute the force evenly over a greater length of pipe than the conventional die.
[0010] An object of the present invention is therefore to provide a die assembly with a flexible die that distributes the bending force over the entire bend.
[0011] A further object of the present invention is to provide such a die assembly which may be retrofit into conventional pipe bending machines.
[0012] Further objects and advantages of the present invention will become apparent from the specification and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a side view detail of the die of the present invention shown on a length of pipe with the die outer housing removed and prior to bending.
[0014] [0014]FIG. 2 is a view taken along line A-A of FIG. 1 illustrating one of the interior plates in position prior to bending.
[0015] [0015]FIG. 3 is an end view cross-sectional of the die of FIG. 1.
[0016] [0016]FIG. 4 is an end elevation of the die of FIG. 1.
[0017] [0017]FIG. 5 is a bottom view of the die of the present invention wherein the liner bars are not shown.
[0018] [0018]FIG. 6 is a top plan view detail of the eggcrate assembly of the die of FIG. 1.
[0019] [0019]FIG. 7 is a side view of the eggcrate assembly of FIG. 7.
[0020] [0020]FIG. 8 is an elevational cross-section of the die of FIG. 1.
[0021] [0021]FIG. 9 is a section of the die of FIG. 1 illustration placement of the liner bars without a coating thereon and without the retaining bands on each end.
[0022] [0022]FIG. 10 is a schematic illustrating the die of FIG. 1 in a flex position with only one flex bar in place.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] The die assembly described with respect to the drawings and specification is designed for use in bending pipe in a pipe bending machine which includes a main frame having connected thereto, directly or indirectly, a stiffback, and stiffback clamp, a pin-up shoe and pin-up clamp and associated power actuating means which are well known and have been described in U.S. Pat. No. 3,834,210, incorporated herein by reference. Therefore, they will not be shown in detail herein.
[0024] Attention is first directed to FIG. 1 which is an elevational view of the die assembly of the present invention shown apart from the pipe bending machine with its external housing removed. Die assembly 10 is shown in a relaxed position resting upon a section of pipe 12 prior to bending. Shown therein, die assembly 10 includes a plurality of essentially identical plate segments 14 - 14 N retained between first end plate 16 and second end plate 18 . These plate segments include an arcuate internal shape as will be described in greater detail below with regard to FIG. 2 and are arranged along the length of die assembly 10 . Die assembly 10 further includes an eggcrate assembly 20 . Eggcrate assembly 20 (described further below) includes a spring plate 22 which is the member which determines the curvature of the bend of pipe 12 .
[0025] Referencing FIG. 2, a view taken along line A-A of FIG. 1, external housing 11 enshrouds die plates 14 - 14 N and eggcrate assembly 20 . External housing 11 is shaped and notched so as to fit into and replace the conventional die in the known pipe bending apparatus such as disclosed in U.S. Pat. No. 3,834,210. The shape of external housing 11 takes into consideration the supporting structure within the conventional pipe bending apparatus. It is understood that without the limitations imposed by the conventional bender design, external housing 11 and plate segments 14 could be shaped and configured differently without departing from the spirit and scope of this invention.
[0026] [0026]FIG. 1, when taken in combination with FIG. 2, shows the orientation and geometry of plate segments 14 which shall next be described. Each individual plate segment 14 is shaped so as to include an arcuate cut out 26 therein. Arcuate cut out 26 is sized and shaped to conform to the external circumference of pipe 12 and is dependent upon the size of pipe selected. Each segment plate 14 includes a planer top surface 28 which abuts eggcrate assembly 20 .
[0027] The die assembly 10 of FIG. 2 is depicted in a relaxed state where no force is applied to pipe 12 against die assembly 10 as when in the bending process. A space 46 and 48 exists between each plate segment 14 and the inside of the external housing 11 . The purpose for this is to allow plate segments 14 to move in response to flex of tie rods 30 and 32 and to ensure that plate segments abut against spring plates 22 at top surface 28 and not against exterior housing 11 .
[0028] The plurality of plate segments 14 through 14 N are aligned within die assembly 10 supported from and resting upon a pair of tie rods 30 and 32 . Tie rods 30 and 32 extend the length of die assembly 10 through first end plate 16 , each individual segment plate 14 - 14 N and out from second end plate 18 . Each individual segment plate 14 - 14 N is placed on tie rods 30 and 32 such that a space exists between each individual segment plate 14 - 14 N. In the preferred embodiment, these spaces are maintained through the use of a series of small metal shims or spacers inserted between each individual segment plate. As a result, plate segments 14 - 14 N are substantially free floating on tie rods 30 and 32 and not connected to one another. When assembled, flexible die 8 is not rigid but rather highly flexible.
[0029] Tie rods 30 and 32 are capable of substantial flex along their respective longitudinal axes. In the preferred embodiment, tie rods 30 and 32 are constructed of 5160 spring steel, commercially available. However, it is understood that other suitable known flexible materials could be substituted.
[0030] A spacer 34 is inserted on each tie rod 30 and 32 between end plate 16 and plate segment 14 . Similarly, three washers 36 or other suitable bushing materials are positioned on each tie rod 30 and 32 between segment plate 14 N and second end plate 18 . Accordingly, plate segments 14 - 14 N are “sandwiched” between spacer 34 and bushing 36 along tie rods 30 and 32 and maintained in free floating alignment thereon. Gaps 17 and 19 are created by spacers 34 and 36 along the lengths of tie rods 30 and 32 . Gaps 17 and 19 are contemplated to allow die assembly 10 to be retrofit into the conventional pipe bender apparatus which typically includes two arcuate supports which bound and secure the conventional die. Since in the preferred embodiment, die assembly 10 is longer than the conventional die, the assembly must allow for, and integrate, these supports without the necessity of extensive machining or modification for retrofit of the bender apparatus.
[0031] The number and position of plate segments of 14 - 14 N corresponds to the length of eggcrate assembly 20 and is determined by the diameter of pipe selected. The radius of curvature of spring plate 22 will vary according to the diameter of pipe selected.
[0032] The ends of tie rods 30 and 32 are threaded to receive nuts 38 and 40 thereon. A spring 42 is inserted between nut 38 and end plate 16 . Likewise, a spring 44 is inserted between nut 40 and end plate 18 . It is understood that although only tie rod 30 is illustrated in FIG. 1, tie rods 30 and 32 are assembled in identical manner. Springs 42 and 44 apply pressure to end plate 16 and 18 toward plate segments 14 - 14 N but allow plate segments 14 - 14 N to move along the length of tie rods 30 and 32 when tie rods 30 and 32 flex.
[0033] Accordingly, an assembly is described wherein plate segments 14 - 14 N are sandwiched between end plates 16 and 18 with spaces between each individual plate segment 14 - 14 N wherein each plate segment floats, or moves freely with regard to its adjacent plate segment in response to flex of tie rods 30 and 32 . The free floating plate assembly allows the pressure point (hotspot) applied to the pipe during the bend to move and be distributed along the length of the die from one plate segment to another.
[0034] Die assembly 10 is pinned into the bending machine by shaft 24 in a conventional manner. A shaft 24 pins die assembly 10 within the bending machine. Shaft 24 extends through first end plate 16 , eggcrate assembly 20 and out of second end plate 18 . The die assembly hangs inside the bender from shaft 24 while the eggcrate assembly is bolted to the exterior housing.
[0035] Referring to FIG. 3, a section taken just inboard of first end plate 16 which depicts external housing 11 and includes a housing face 13 thereon. Housing face 13 is secured to external housing 11 such as by welding or other suitable means and is an integral part thereof. Flexible die 8 including plate segments 14 - 14 N are within external housing 11 . A housing face is likewise secured to external housing 11 on the opposite end (FIG. 4).
[0036] [0036]FIG. 4 is an assembled end elevation of die assembly 10 surrounding a pipeline pipe 12 . Die assembly 10 includes external housing 11 with housing face 13 thereon wherein the flexible die 8 (of FIG. 3) is retained within external housing 11 . FIG. 4 shows first end plate 16 adjacent housing face 13 . Tie rods 30 and 32 are shown extending through first end plate 16 but not through housing face 13 . This is so that flexible die 8 as well as tie rods 30 and 32 are able to flex freely within external housing 11 and not retained thereby.
[0037] Shaft 24 is shown extending through first end plate 16 and housing face 13 and into eggcrate assembly 20 (as depicted in FIG. 1). As stated previously, shaft 24 secures and suspends die assembly 10 within the bending apparatus. Shaft 24 extends through an oval channel 50 in first end plate 16 . Oval channel 50 allows first end plate 16 to move vertically in response to flex of tie rods 30 and 32 so that shaft 24 does not hinder the flex of tie rods 30 and 32 in the entirety of flexible die 8 within external housing 11 .
[0038] [0038]FIG. 5 is a bottom view of die assembly 10 which depicts external housing 11 including housing face 13 and housing back 52 . Flexible die 8 is shown positioned within external housing 11 in an assembled fashion with the exception that FIG. 5 does not show the liner bars (discussed below). Plate segments 14 - 14 N are shown positioned within housing 11 aligned along tie rods 30 and 32 with spaces therebetween so that each individual liner plate segment is capable of independent movement with respect to its adjacent plate segments in response to flex of liner bars 30 and/or 32 . FIG. 5 shows the manner in which plate segments 14 - 14 N are free floating along tie rods 30 and 32 while being retained or sandwiched between first end plate 16 and second end plate 18 of flexible die 8 .
[0039] With reference to FIG. 6, eggcrate assembly 20 shall now be discussed. FIG. 6 is a top plan view of eggcrate assembly 20 which includes a substantially rectangular welded frame 54 with a plurality of support ribs 55 and 56 welded longitudinally therein. Ribs 55 and 56 provide structural support to eggcrate assembly 20 and also provide structural support for the spring plates secured onto eggcrate assembly 20 . The number of ribs 56 is dependent upon the size of the eggcrate which varies according the diameter of pipe which is to be bent. A series of cross-supports 58 are welded within frame 54 between ribs 56 to provide additional support. A pair of middle cross-supports 60 are welded between middle ribs 56 but are recessed within frame 54 so as to allow shaft 24 (of FIG. 2) to extend along the length of eggcrate assembly 20 when the die is assembled. A mounting plate 62 is welded on each corner of eggcrate assembly 20 within frame 54 . Mounting plate 62 includes a hole 64 drilled and tapped therein. Holes 64 on mounting plate 62 align with holes drilled in the exterior housing of the die assembly so that eggcrate assembly 20 is bolted within the exterior housing upon assembly of the die.
[0040] A plurality of spring plate mounting plates 68 are welded within the framework of eggcrate assembly 20 . Spring plates 66 are screwed onto spring plate mounting plates 68 by screws 70 countersunk into the surface of spring plates 66 .
[0041] [0041]FIG. 7 is a view taken along line 7 - 7 of FIG. 6 and depicts the manner in which the spring plates 66 are secured to eggcrate assembly 20 . Spring plates 66 are a series of spring steel plates machined to a predetermined external radius and bolted to eggcrate assembly 20 . In a preferred embodiment, three or more such spring plates 66 are bolted to eggcrate assembly 20 to substantially cover its width. Spring plates 66 form the structure against which flexible die 8 is pressed against during the bending process. The radius of curvature of spring plates 66 determines the radius of curvature of the resulting bend in the pipe.
[0042] The fulcrum point 72 of spring plate 66 is positioned toward the pin-up end 74 of eggcrate assembly 20 . It is at this fulcrum point 72 that the radius of curvature of spring plate 66 is determined. Since the fulcrum point 72 is positioned closer to pin-up end 74 then stiffback end 76 of eggcrate assembly 20 , the radius of curvature intersection with pin-up end 74 means that eggcrate assembly 20 will be thicker at pin-up end 74 than stiffback end 76 since spring plate 66 follows the radius of curvature as set from fulcrum point 72 . It is known in the art that a certain amount of bend can be achieved by the pin-up clamp on pin-up end 74 .
[0043] [0043]FIG. 8 is an elevational cross-section of the die assembly 10 of the present invention in a relaxed state prior to bending. Flexible die 8 of die assembly 10 may also include a plurality of liner bars positioned within the arcuate cut-out portion of the plate segments 14 - 14 N. Referring to FIG. 8 with combination of FIG. 2, a plurality of liner bars 80 - 80 N. Liner bars 80 - 80 N are in the preferred embodiment ½″×½″ 4140 heat treated spring steel which extends the length of flexible die 8 between first end plate 16 and second end plate 18 . Liner bars 80 - 80 N contact pipe 12 between the individual plate segments 14 - 14 N and pipe 12 . Liner bars 80 - 80 N are flexible so as to be able to flex in accordance with the flex of tie rods 30 and 32 . Liner bars 80 - 80 N are preferably coated with a material such as urethane in order to minimize the potential of scratching or scarring to the exterior of pipe 12 which may otherwise be caused by metal-to-metal contact between the flexible die 8 and the pipe 12 .
[0044] Liner bars 80 - 80 N are positioned within arcuate cut-out 26 of plate segments 14 - 14 N so as to include a space therebetween. The urethane 82 is applied to the liner bars so that it fills the space between adjacent liner bars within arcuate cut-out 26 . Liner bars 80 - 80 N are preferably coated with urethane in pairs such that two adjacent liner bars are fused together. Urethane on one edge of the formed pair bridges the space between adjacent pairs of liner bars. It is understood, however, that liner bars 80 - 80 N could be coated individually or in groups greater than two depending upon the application.
[0045] Liner bars 80 - 80 N serve to distribute the pressure applied against the pipe by plate segments 14 - 14 N in order to avoid transverse scratching or scarring of the exterior of pipe 12 which could occur by direct contact between plate segments 14 - 14 N and the exterior of pipe 12 .
[0046] Each individual liner bar 80 is of a length sufficient to span the distance between first end plate 16 and second end plate 18 . Each liner bar 80 includes a tab on each end wherein the liner bar is bent beyond the last plate segment on the end of flexible die 8 .
[0047] [0047]FIG. 3 depicts liner bars 80 - 80 N encoated with urethane 82 in contact with the exterior surface of pipe 12 such as in the process of bending.
[0048] Taking FIG. 4 in combination with FIG. 9, wherein FIG. 9 is a cross-section showing liner bars 80 - 80 N in place. FIG. 4 illustrates the manner in which liner bars 80 - 80 N are retained within die assembly 10 . The crimp segments of each liner bar 80 - 80 N extends beyond first end plate 16 on the pin-up end and beyond second end plate 18 on the stiffback end. First end plate 16 and second end plate 18 include a pair of tabs 84 positioned on its face with one on the side of tie rod 30 and one on the side of tie rod 32 . Tabs 84 extend outwardly from first end plate 16 and second end plate 18 in the pin-up and stiffback directions, respectively. A retaining ring 86 is positioned adjacent liner bars 80 - 80 N and secured to tabs 84 such as by bolting. Retainer ring 86 thereby clamps the crimp segments of liner bars 80 - 80 N between itself and arcuate cut-out 26 of first end plate 16 . In likewise fashion, a retaining ring is secured to the crimp segmentss of second end plate 18 thereby clamping the crimp segments on the opposite ends of liner bars 80 - 80 N between itself and the arcuate cut-out of second end plate 18 . Liner bars 80 - 80 N are thereby clamped on each end of die assembly 10 . In the preferred embodiment, the crimp segments crimp segments of liner bars 80 - 80 N are not coated with urethane. Although liner bars 80 - 80 N are clamped to first end segment 16 and second end segment 18 , they are capable of movement within the circumference of arcuate cut-out 26 .
[0049] [0049]FIG. 10 is schematic view of the die assembly 10 of the present invention to illustrate the manner in which the flexible die 8 acts against pipe 12 and spring plates 66 in order to produce a uniform bend in pipe 12 . The die apparatus 10 is shown in FIG. 10 in a full flex position. In the position of FIG. 10, the pin-up applies a force in the direction identified as A and B upon pipe 12 . In response, pipe 12 begins to bend and transfers the force against plate segments 14 to 14 (N-x) (wherein x equals the number of plate segments between fulcrum point 72 and plate segment 14 N). Tie rod 32 then flexes in response to forces A and B applied to plate segments 14 through 14 (N-x) against radius plate 66 of eggcrate assembly 20 . Eggcrate assembly 20 applies resistive forces A′ and B′ back upon plate segments 14 - 14 (N-x). Since plate segments 14 - 14 (N-x) are free floating and spaced along tie rod 32 , the ends of plate segments 14 - 14 (N-x) adjacent to pipe 12 fan apart and distribute the resistive forces A′ and B′ substantially equally among plate segments 14 - 14 (N-x). This force is further distributed through liner bars 80 which are placed transverse to the plate segments 14 . As a result, the forces causing pipe 12 to bend are distributed evenly along the bend corresponding to the number of plate segments. The result is the bend in pipe 12 conforms to the radius of curvature of spring plate 66 between fulcrum 72 and pin-up end 74 .
[0050] In like manner, the stiffback of the bending apparatus applies a bending force to pipe 12 represented as C, D, E, and F in FIG. 10. This force is transferred from pipe 12 to plate segments 14 (N-x) through 14 N. This force is then transferred to spring plate 66 of eggcrate assembly 20 . Eggcrate assembly 20 applies a resistive force represented as C′, D′, E′, F′ against plate segments 14 (N-x) through 14 N. Plate segments 14 (N-x) through 14 N being free floating on tie rod 32 and spaced from one another assume the radius of curvature of spring plate 66 between fulcrum 72 and stiffback end 76 . In response to the flex of tie rod 32 , the portions of the plate segment adjacent the pipe fan out such that the resistive force transferred through plate segments 14 (N-x) through 14 N are distributed substantially equally among plate segments 14 (N-x) through 14 N. Liner bars 80 further distribute the bending force along the length of pipe 12 where the bend is achieved. A smooth, uniform bend in pipe 12 substantially equal to the radius of curvature of spring plate 66 between fulcrum 72 and stiffback end 76 is obtained in pipe 12 .
[0051] The optimal radius of curvature for the spring plate 22 on the eggcrate assembly 20 is dependent upon the diameter of the pipe. The amount of bend per arc foot is dependent upon factors such as the wall thickness of the pipe, the yield point of the pipe material and the use of a pipe mandrel. However, for the purpose of exemplification, it has been found that where all factors are equal, and the die of the present invention is used, the recommended die radius was determined to be 1.33 times that of the conventional die. For example, for 12″ X-52 pipe having a wall thickness of ⅜″ (12⅜″ O.D.), the recommended conventional die radius is 12′9″. However, using the die of the present invention for the same pipe, a die radius of 17′0″ has been found to be acceptable. As a result, where the recommended bend per arc foot is 2.3° using a conventional static die, the bend per arc foot using the die of the present invention was determined to be 5.5°.
[0052] For the purpose of exemplification, a die assembly such as die assembly 10 intended to bend 12 inch x-52 pipe (12⅜″ D) may have the following suitable configuration:
Number of 1/2 wide plate segments 64 Spaced apart 1/8″ with a 7″ radius on arcuate cut-out Number of liner bars 30 Spaced apart 1/8″ coated with 90 durometer urethane formed in pairs Number of 32″ spring plates 4 formed of 5160 spring steel having a Radius of curvature of 17′ 0″ with fulcrum point 12″ from pin-up end
[0053] While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiment set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled. | A die assembly for machines used to bend lengths of pipe for pipeline applications. The die assembly includes three major components, an exterior housing, a flexible die, and an eggcrate assembly. The exterior housing encompasses the flexible die and eggcrate assembly and pins into conventional bending machines. The flexible die includes a plurality of narrow plate segments positioned along a pair of tie rods. The plate segments are free floating and spaced so as to converge or diverge with respect to the direction of flex of the tie rods. The eggcrate assembly provides support for a plurality of spring plates. Each spring plate has a radius of curvature consistent with the amount of desired bend in the length of pipe. | 1 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to an intraocular insert for implantation in the interior of the human eye to replace the human crystalline lens.
Macular degeneration is a disorder in which the central retinal area (the macula) degenerates, e.g., because of age (age-related macular degeneration, or AMD), diabetic retornopathy, ocular vascular accidents, retinal dystrophies as for example cone dystrophy, central nervous system (CNS) diseases, etc. These disorders in the macular area cause difficulty in vision such that the afflicted person is unable to read without special telescopic or microscopic eyeglasses that create a magnification of the object on the retina. However, when an outside telescope is used, the visual field is very narrowly restricted, and therefore the afflicted person has to move his or her head back and forth to follow the lines being read.
OBJECT AND SUMMARY OF THE INVENTION
An object of the present invention is to provide a novel intraocular insert for implantation in the interior of the human eye particularly for use by persons suffering from macular degeneration diseases.
According to the present invention, there is provided an intraocular insert for implantation in the interior of a human eye, characterized in that the insert includes a converging lens carried by the insert to face the anterior side of the eye; and a diverging lens carried by the insert in alignment with and spaced behind the converging lens to face the posterior side of the eye.
More particularly, and according to the preferred embodiments of the invention described below, the insert includes a converging lens to face the anterior side of the eye; and a diverging lens in alignment with and spaced behind the converging lens to face the posterior side of the eye.
An intraocular insert constructed in accordance with the foregoing feature increases the visual field that the patient enjoys. Moreover, it obviates the need of using an outside telescope, and therefore the need for the patient to move the head back and forth when scanning lines being read. A further advantage in implanting the above intraocular device, to replace the human crystalline lens, is that it enables the patient also to use outside magnification (e.g., spectacles or contact lenses) in combination with the intraocular insert to achieve higher magnification than possible by using just magnifying spectacles or contact lenses alone.
Further features and advantages of the invention will be apparent from the description below.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings.
FIG. 1 is a horizontal section through the eye illustrating a first embodiment of intraocular insert constructed in accordance with the present invention.
FIG. 2 is a horizontal section through the eye illustrating a second embodiment of intraocular insert constructed in accordance with the present invention.
FIG. 3 is a horizontal section through the eye illustrating a third embodiment of intraocular insert constructed in accordance with the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference first to FIG. 1, there is illustrated a horizontal section of a human eye, including one form of intraocular insert, generally designated 10, constructed in accordance with the present invention. The means for fixing the insert 10 in the eye are not described herein, as many such means are known for mounting artificial intraocular lenses and can be used for fixing the intraocular insert 10.
The intraocular insert 10 includes a body member 11, of generally convexo-convex or convexo-plano configuration; that is, its front or anterior face 12 facing the anterior side of the human eye is of convex configuration, and similarly its rear or posterior face 13 facing the posterior side of the human eye is of convex (or planar) configuration.
The body member 11 is formed with a central cylindrical bore 14 extending through its anterior face 12 and its posterior face 13.
A converging lens 15 is fixed within bore 14 at the anterior side of body member 11, and a converging lens 16 is fixed within the bore at the posterior side of the body member. The diverging lens 16 is thus aligned with the converging lens 15 but is spaced rearwardly of the converging lens by the cavity defined by bore 14. The two lenses 15 and 16 thus define a Galilean telescopic system commonly used in opera glasses.
Such a telescopic system, when incorporated in an intraocular insert implanted into the human eye, in place of the natural crystalline lens, increases the visual field that the patient enjoys, thereby enabling the patient to read fine print without the use of an outside telescope. Thus, the normal eye movements in the reading process are preserved, and the patient does not need to move his or her head from one side of the line to the other in order to read, as generally required when using external telescopic spectacles.
The two lenses 15 and 16 may be made of the same material as presently used for making intraocular lenses, such as plastic (e.g., methyl methacrylate), glass, sapphire or the like. The body member 11 may be of the same material. The cavity 14 between the two lenses 15 and 16 may be filled with air, a gas, or a suitable liquid such as water.
FIG. 2 illustrates an intraocular insert, generally designated 20, similar to insert 10 of FIG. 1, and also including a body member 21 formed with a central cylindrical cavity 24 covered at its front side by a converging lens 25 facing the anterior side of the eye, and at its rear side by a diverging lens 26 facing the posterior side of the eye. In FIG. 2, however, the converging lens 25 is integrally formed with the body member 21, whereas the diverging lens 26 is formed as a separate element and is fixed, as by an adhesive or a weld, in the rear part of the cylindrical cavity 24 of the body member.
It will be seen that in the constructions of both FIGS. 1 and 2, the outer periphery of the anterior face of the converging lens (15, 25) is substantially flush with the anterior face of the body member 11; and similarly, the outer periphery of the posterior face of the diverging lens (16, 26) is substantially flush with the posterior face of the body member 11, 21.
FIG. 3 illustrates an intraocular insert, generally designated 30, also including a body member 31 formed with a central cylindrical bore 34 closed at the anterior end by a converging lens 35 and at the posterior end by a diverging lens 36. In this case, however, the converging lens 36 is mounted to a support 37 so that it extends rearwardly of the posterior face of the body member 30 and thereby produces a larger space between it and the converging lens 35. Such an arrangement increases the magnification of the intraocular insert.
In all other respects, the intraocular insert 30 illustrated in FIG. 3 is constructed and operates in the same manner as described above with respect to FIGS. 1 and 2.
While the invention has been described with respect to three preferred embodiments, it will be appreciated that these are set forth merely for purposes of example, and that many other variations may be made. For example the insert could include more than two lenses, combination lenses, holographic lenses, etc. In addition, the lenses could be mounted on a common holder (e.g., at the opposite ends of a cylindrical tube) fixed within a bore in the body member. Many other variations, modifications and applications of the invention will be apparent. | An intraocular insert for implantation in the interior of a human eye, characterized in that the insert includes a converging lens to face the anterior side of the eye, and a diverging lens in alignment with and spaced behind the converging lens to face the posterior side of the eye. | 0 |
FIELD OF THE INVENTION
[0001] The invention relates to a rolling bearing, in particular, cylindrical roller bearing, which has rolling bodies that are also driven outside of the load zone of the rolling bearing.
BACKGROUND
[0002] For the rotating support, for example, of a shaft, it is generally typical to provide rolling bearings that have an inner ring, an outer ring surrounding the inner ring coaxially, and rolling bodies that roll on raceways provided by the outer ring and the inner ring. Due to manufacturing tolerances, however, in practice it cannot be ruled out that rolling bearings have minimal play. This play can have the result that the rolling bodies, which in an ideal, completely play-free rolling bearing are in constant contact with the two raceways and therefore are driven constantly for rotation, for example, of the inner ring relative to the outer ring, lose contact with one of the raceways and consequently are no longer driven. This loss of contact of the rolling bodies with the raceway always occurs outside of the load zone of the rolling bearing. Only for the sake of completeness is it noted that a load zone of a rolling bearing is considered the part of the bearing circumference at which the rolling bodies transfer forces. If the rolling bodies lose contact with the raceway outside of the load zone, the kinematic energy that the rolling bodies have received while rolling through the load zone is reduced by effects of friction and the rotational speed is reduced. This phenomenon occurs especially in slowly rotating rolling bearings and/or rolling bearings with large diameters, because in these rolling bearings the dwell time of the rolling bodies outside of the load zone is comparatively large.
[0003] Then if the rolling bodies somewhat decelerated by the lack of raceway contact appear back in the load zone, the rotational speed of the rolling bodies is abruptly increased again due to the contact of the rolling bodies with the raceway. This increase of rotational speed then leads to sliding friction between the raceway and rolling bodies, which decreases the service life of the rolling bearings.
[0004] From DE 1 955 238 U, a rolling bearing is known in which elastic elements provide for the freedom of play in the bearing. Here, elastic elements such as rubber rings can be arranged either on the rolling bodies or on a bearing ring. If the elastic elements are located on a bearing ring, then additional expansion rings can be provided that are loaded with a force by the elastic elements and contact the rolling bodies.
[0005] Another rolling bearing formed as a cylindrical roller bearing is known from DE 10 2006 042 676 A1. In this case, tensioning elements are constructed as arc segments that extend, for example, over an angle of 90° or 120° on the circumference of the rolling bearing and are loaded by other elements, namely pressure pieces formed as pegs and annular springs with a force acting in the radial direction of the bearing.
[0006] Another known approach for provided freedom from play in a cylindrical roller bearing is the use of hollow rollers. From DE 10 2006 055 027 A1, the use of hollow rollers for a cylindrical roller bearing with a rolling body cage is known. To force the rotation of the rolling body cage with kinematically correct rotational speed in any load state, some rolling bodies of the bearing are replaced by hollow rollers that have, in the unloaded state, a slightly larger diameter than the other solid cylindrical rollers. Due to the hollow rollers located with pre-tensioning in the bearing, the cage is carried along at very low loads, but a kinematically ideal movement of the other rolling bodies is not simultaneously produced. Incidentally, the loading capacity of the rolling bearing by the hollow rollers being used is reduced in comparison to a cylindrical roller bearing that has only solid rollers.
[0007] A hollow roller with higher radial loading capacity is known from DE 10 2007 062 391 A1. Here, an overload body that ensures that the material loading of the hollow roller remains in a permissible range is arranged within the actual hollow roller.
SUMMARY
[0008] The invention is based on the objective of disclosing a rolling bearing, in particular, cylindrical roller bearing, which is improved relative to the cited prior art and in which freedom from play is produced in an especially simple and effective way.
[0009] This object is achieved by a rolling bearing with one or more features of the invention. The rolling bearing is preferably constructed as a radial bearing, in particular, a radial cylindrical roller bearing; however, it could also be a pendulum roller bearing, for example.
[0010] The rolling bearing comprises two bearing rings each of which have a running surface for rolling bodies, in particular, cylindrical rollers. The bearing rings are called outer ring and inner ring without limiting generality. In actuality, the part designated as outer ring could also be, for example, a housing in which a hole is located that directly forms the running surface for the rolling bodies. The part designated as inner ring can be, for example, a solid or hollow shaft. In all cases, the rolling bearing is suitable for transferring radial forces between the inner ring and the outer ring.
[0011] To produce the desired, play-free contact between all rolling bodies of a rolling bearing and its two raceways, at least one completely closed middle ring is provided that has an axial length that is reduced relative to the axial extent of the rolling bodies and surrounds all of the rolling bodies like an envelope circle. In this way, the middle ring that can be formed very easily from a tube section or a sheet ring creates another raceway that is used by itself for driving all of the rolling bodies of the rolling bearing and is positioned regardless of whether the rolling bodies of the rolling bearing are inside or outside the load zone of the rolling bearing. This drive of all rolling bodies by the middle ring or middle rings ensures that the middle ring or middle rings are decoupled radially from the surrounding outer ring but are simultaneously rotationally locked in it. This radial decoupling is created essentially by at least one circumferential groove that is formed in the inner side of the outer ring and its axial extent is greater than the axial length of the middle ring and its radial depth is greater than the thickness of the middle ring. The one-piece construction of the middle ring and its free radial movement ensure that the rolling bodies can always roll on the middle ring independent of the installation position of the rolling bearing or the position of the load zone, also without the need for additional components, and thus its rotational speed is maintained from the exit from the load zone until reentry into the load zone.
[0012] Only for the sake of completeness it shall be noted that the designation middle ring is not necessarily associated with a central position in the bearing. Such a middle ring could also be provided close to one or also both axial ends of the rolling bodies.
[0013] A very simple, rotationally locked fixing of the middle ring in the groove is given if there is at least one projection provided on the middle ring or in the groove, wherein this projection engages in a pocket that has a complementary shape to the projection on the middle ring or in the groove.
[0014] The assembly of the rolling bearing is simplified if each projection extends in the axial direction and engages in a pocket similarly extending in the axial direction.
[0015] Only for the sake of completeness it shall be noted that regardless of whether the projections and pockets extend in the axial or radial direction and the radial extent of the projections and pockets is adjusted to each other such that it is always possible to completely receive the middle ring in the groove in the radial direction.
[0016] The smooth running of the rolling bearing is improved if a radially flexible spring element that centers the middle ring in the load-free state of the rolling bearing is placed in the groove.
[0017] It is especially preferred if the spring element is formed by an O-ring made from an elastomer. Because the O-ring is made, for example, from rubber or an artificial elastomer, the smooth running of the rolling bearing is improved not only by the damping effect of the elastomer, but also a sufficiently large friction-fit fixing of the middle ring in the outer ring is simultaneously caused by the contact between the O-ring and the middle ring.
[0018] Rolling bearings according to the invention can also be used at high temperatures of the rolling bearing or environment if the spring element is formed from a circumferential, corrugated, or serrated metal band.
[0019] The rotationally locked fixing of the middle ring is improved if the middle ring and/or the groove is provided with edges and these edges form a support for the spring elements in the circumferential direction.
[0020] The rolling bearing according to the invention is suitable, in particular, for large size bearings like those used, for example, in wind turbines.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] An embodiment of the invention is described in more detail below with reference to a drawing. Shown herein are:
[0022] FIG. 1 a section diagram of a rolling bearing,
[0023] FIG. 2 a section AA through a rolling bearing according to FIG. 1 ,
[0024] FIG. 3 a view into an outer ring,
[0025] FIG. 4 another construction of a rolling bearing in a diagram according to FIG. 2 ,
[0026] FIG. 5 a fixed O-ring, and
[0027] FIG. 6 another construction of a spring element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] FIG. 1 shows, in cross section, a rolling bearing 1 that is formed as a cylindrical roller bearing and whose rolling bodies 2 , namely cylindrical rollers, roll between an outer ring 3 and a shaft 4 . Together the outer ring 3 and the shaft 4 , at whose position a non-solid part, namely an inner ring, could also be arranged, are designated bearing rings 3 , 4 . With respect to the basic function of the cylindrical roller bearing 1 , the prior art cited above is referenced.
[0029] The rolling bodies 2 contact both bearing rings 3 , 4 in a main load zone HL, at the bottom in the arrangement according to FIG. 1 . The raceways on the outer ring 3 and on the shaft 4 , which is called, in general, inner ring, are marked with the reference symbols 5 and 6 , respectively. A radial force acting on the shaft 4 is designated F.
[0030] Outside of the main load zone HL, in an unloaded zone UZ, the rolling bodies 2 are on the shaft 4 due to the force of gravity, while they are somewhat spaced apart from the outer ring 3 . In order to nevertheless move all of the rolling bodies 2 of the rolling bearing 1 continuously at the kinematic rotational speed, there is, in a groove 7 that can be seen in FIG. 2 and is arranged centrally in the axial direction in the outer ring 3 , a middle ring 8 that surrounds the rolling bodies 2 like an envelope circle HK. In a way that is not shown, the rolling bodies 2 are guided in a cage.
[0031] Because all rolling bodies 2 —as shown in FIG. 1 —contact the middle ring 8 in this embodiment, these are also driven by rolling on the middle ring 8 when the shaft 4 rotates relative to the outer ring 3 , regardless of whether the rolling bodies 2 are in the main load zone HL or in the unloaded zone UZ. This is achieved in that the middle ring 8 contacts the rolling bodies 2 without clearance and the middle ring 8 is free from the outer ring 3 of the rolling body 2 in the radial direction. This can be seen in FIG. 2 how the radial clearance of the middle ring 8 relative to the outer ring 3 is achieved in that the radial extent E 1 of the groove 7 is greater relative to the radial extent E 2 of the middle ring 8 and much greater so that the groove is suitable for completely holding the middle ring 8 . Maintaining these relationships, that is, the complete holding of the middle ring 8 in the groove 7 is especially important in the main load zone HZ of the rolling bearing 1 , so that only the rolling bodies 2 “bear weight” there, that is, forces from the inner ring 4 onto the part of the outer ring 3 that has no groove. This radial clearance of the middle ring 8 that has a circular construction also means, however, that in comparison to the main load zone HL, the middle ring 8 can also assume a greater distance A to the groove base 9 in the unloaded zone UZ due to its extension on the groove 7 .
[0032] To guarantee rolling of the rolling bodies 2 on the outer ring 3 , it is important that the middle ring 8 is arranged rotationally locked despite its radial clearance relative to the outer ring 3 . A simple construction of a rotationally locked fit is shown in FIG. 3 , which has a view into an outer ring 3 of a rolling bearing 2 according to the invention for its object. The middle ring 8 is provided in this embodiment on each of its two edges 10 . 1 with a projection 11 that extends in the axial direction and engages in pockets 12 that have complementary shapes to the projections 11 and are constructed in the two edges 10 . 2 of the groove 7 . Due to the rolling of the rolling bodies 2 on the middle ring 8 placed in the groove 7 , the middle ring 8 is exposed to driving forces in the circumferential direction of the rolling bearing 2 and these forces impose a co-rotation of the middle ring 8 relative to the outer ring 3 thanks to the complementary shapes of the projections 11 and pockets 12 . It can also be seen in the diagram according to FIG. 3 that the axial width of the middle ring 8 is somewhat reduced relative to the axial width of the groove, in order to rule out jamming of the middle ring 8 in the groove 7 .
[0033] Corresponding to the construction according to FIG. 4 , co-rotation of the middle ring 8 is prevented by a spring element 13 in the groove 7 between the middle ring 8 and the groove base 9 . This spring element 13 is formed as an O-ring 14 . The O-ring 14 , which is placed in the groove 7 and can be made from rubber or a plastic elastomer, has the effect by itself, due to the slip-inhibiting action of such materials, that the middle ring 8 is fixed rotationally locked in the groove 7 .
[0034] It can also be seen from the construction according to FIG. 4 that the O-ring 14 fills out the space between the middle ring 8 and the groove base 9 such that the O-ring 14 contacts the middle ring 8 and the groove base 9 . Because the O-ring is made from elastic material and always fills out the space between the middle ring 8 and groove base 9 in the radial direction, this contributes to smooth running, regardless of whether the middle ring 8 —as shown in the lower part of FIG. 4 —is completely held by flattening forces of the O-ring 14 by the groove 7 or—as shown in the upper part of FIG. 4 —projects somewhat from the groove 7 .
[0035] If the slip inhibition that is realized just by the O-ring 14 is not sufficient, in another embodiment shown in FIG. 5 , the slip inhibition can be further improved by providing edges 15 in the groove 7 and/or on the middle ring 8 . According to the construction in FIG. 4 , these edges 15 are formed in the groove base 9 and on the outer lateral surface 16 of the middle ring 8 , wherein the edges 15 on the middle ring 8 are pointed in the direction of the groove base 9 and the edges 15 on the groove base 9 are pointed in the direction of the middle ring 8 . When the rolling bearing 1 is mounted, the edges 15 —as shown in FIG. 6 —are pressed into the O-ring 14 and improve, due to the serrations, the rotationally locked fit of the middle ring 8 relative to the outer ring 3 .
[0036] FIG. 6 shows another construction of a spring element 14 . This spring element 13 is constructed as a corrugated metal spring 17 and fills the radial space between the groove base 9 and the middle ring 8 . As explained in relation with the O-ring 14 , the corrugated metal spring 17 does not only contribute to the smooth running of the rolling bearing 1 , but also simultaneously ensures that an eccentricity of the middle ring 8 relative to the center of the outer ring 3 is absorbed elastically. The shown edges 15 that extend in the radial direction and have a contour adapted to the corrugated metal spring 17 in the embodiment shown in FIG. 6 ensure that, due to the serrations, relative rotation between the outer ring 3 and middle ring 8 is prevented.
[0037] In addition, in the embodiment according to FIG. 6 , if the corrugated metal spring 17 is constructed as a standalone part, in another embodiment not shown in more detail, the spring effect of radially projecting ribs can be realized that form a one-piece unit with the middle ring 8 , which further reduces the expense.
[0038] Only for the sake of completeness it shall be noted that the figures are not true-to-scale diagrams of the ratios for the object, but are merely of a schematic nature. Also, in the embodiments if only one middle ring 8 placed in a groove 7 is shown, in other—not shown—constructions, two or more combinations formed from groove 7 and middle ring 8 can be provided across the axial length of the rolling bearing 1 for driving the rolling bodies 2 .
[0039] The rolling bearing 1 according to FIG. 1 or 3 can be used, in particular, in use cases in which the forces of gravity significantly influence the bearing kinematics. This is the case, for example, in large size bearings, for example, wind turbine bearings, in which the rolling bodies 2 are especially strongly decelerated outside of the load zone. Because all of the rolling bodies 2 are in physical contact with the middle ring 8 made from steel regardless of whether the rolling bodies 2 are in the main load zone HL or in the unloaded zone UZ, it is guaranteed that the rotational speed of each rolling body 2 about its own axis is approximately maintained also outside of the load zone, so that the rolling body 2 reenters the load zone of the rolling bearing 1 approximately at its kinematic rotational speed.
LIST OF REFERENCE NUMBERS
[0000]
1 Rolling bearing
2 Rolling body
3 Outer ring
4 Inner ring, shaft
5 Raceway
6 Raceway
7 Groove
8 Middle ring
9 Groove base
10 x Edge
11 Projection
12 Pocket
13 Spring element
14 O-ring
15 Edges
16 Outer lateral surface
17 Leaf spring
F Radial force
HL Main load zone
HK Envelope circle
UZ Unloaded zone
E 1 Radial extent of groove
E 2 Radial extent of middle rim
A Distance
L Length
T Depth
D Thickness | A slip-free rolling bearing ( 1 ) is provided, in the outer ring ( 3 ) of which there is formed an encircling groove ( 7 ). The rolling bodies ( 2 ) of this rolling bearing are surrounded, in the manner of an envelope circle, by a central ring ( 8 ) and are in physical contact therewith. To ensure permanent drive of the rolling bodies, the central ring is inserted into the groove so as to be radially free but is fixed rotationally fixedly in said groove, wherein a radial depth of the groove is greater than a thickness of the central ring. The rotational fixing of the central ring in the groove of the outer ring is effected by a spring element. | 5 |
TECHNICAL FIELD
[0001] This disclosure relates to retrieval and disposal devices for pet feces. In particular, the disclosure is directed to modified bags that can be conveniently used to sanitarily pick up and store pet feces until ultimate disposal.
BACKGROUND
[0002] Studies have shown that pet waste that is not picked up and properly disposed of presents environmental and health and safety problems. To combat these problems, many municipalities have introduced ordinances requiring that pet owners retrieve and properly dispose of the their pet's feces. Such ordinances have motivated the development of devices for individuals to conveniently satisfy this obligation.
[0003] Ordinary plastic bags have been widely used to pick up and temporarily store pet feces. One common method of using standard plastic bags to accomplish this task while avoiding direct physical contact between one's hand and the feces is to place the bag over one's hand, grab the feces such that the bag is positioned between one's hand and the feces, and invert the bag so that the feces are contained within the bag. A disadvantage of using an ordinary plastic bag in the above-described manner is that even thought the feces never directly contact the user's hand, the waste must nonetheless be grasped with the fingers, which is highly distasteful for many individuals. In addition, if the waste is soft, it can be difficult to completely remove all the waste from the grass and other ground surfaces. Therefore, there is a need for improved pet waste retrieval and storage devices that provide a unique method of retrieval that takes into consideration the challenges of environmental and health concerns that pet feces retrieval and disposal presents.
[0004] Unfortunately, many of the known devices developed for this purpose include complicated and cumbersome structural features that make them difficult to carry when walking a pet and thus are not widely used. Other devices leave offensive material exposed on external surfaces of the device after the removal operation is performed. Still other devices include non-disposable contaminated portions that require unpleasant cleaning to minimize the health and safety risk associated with the use and storage of feces contaminated devices.
[0005] Accordingly, there is a need for a device that is convenient to carry before and after use while walking one's pet, that is simple to use and easy to manufacture, which would insulate the user from contact with the feces and/or any parts of the device that could have contacted the feces.
SUMMARY
[0006] The disclosure is directed at a device for collecting and storing pet feces that includes: a bag constructed of a flexible sheet material that includes an open end and a closed end; and a pair of opposed panels connected to the bag at the open end, wherein the panels have a width equaling less than or equal to half of the length of the periphery edge and are configured such that they can conveniently be used to scrape the bag against the contaminated surface thereby scooping feces into the bag. The present disclosure is also directed at manufacturing the same and features of enclosing the contamination edges within the bag for handling and transport.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Referring to the Figures, wherein like numerals represent like parts throughout the several views:
[0008] FIG. 1 is a perspective view of a pet waste retrieval and storage bag shown in an open state;
[0009] FIG. 2 is a perspective view of the pet waste retrieval and storage bag of FIG. 1 shown in a closed state;
[0010] FIG. 3 is a side elevation view of the pet waste retrieval and storage bag of FIG. 1 ;
[0011] FIG. 4 is a side elevation view of the pet waste retrieval and storage bag of FIG. 1 during one phase of the manufacturing process;
[0012] FIG. 5 is a cross-sectional view along line 5 - 5 of FIG. 2 ;
[0013] FIG. 6 is a perspective view of an alternative embodiment of a pet waste retrieval and storage bag shown in an open state;
[0014] FIG. 7 is a side elevation view of the pet waste retrieval and storage bag of FIG. 6 ;
[0015] FIG. 8 is a perspective view of the pet waste retrieval and storage bag of FIG. 6 shown in a closed state; and
[0016] FIG. 9 is a cross-sectional view along line 9 - 9 of FIG. 8 .
DETAILED DESCRIPTION
[0017] FIG. 1 is a perspective view of one embodiment of a pet waste retrieval and storage bag 1 configured according to the present invention. The pet waste retrieval and storage bag 1 includes a bag 10 and a pair of panels 30 and 40 attached thereto. In the embodiment shown, the bag is constructed of a flexible plastic and the panels 30 and 40 are constructed of corrugated cardboard. It should be understood that many alternative materials can be employed, some of which will be discussed in more detail below.
[0018] Still referring to FIG. 1 , the bag 10 includes a first major side surface 20 and a second major side surface 18 that are connected together. The bag 10 also includes a closed end 12 and an open end 14 . The side walls at the opening are folded over to form two flaps 22 and 24 and a peripheral edge 16 that defines the opening into the inner cavity of the bag. The flaps 24 and 22 are shown as turned up portions of the bag 10 that are adhered to lower portions 31 and 41 of the panels 30 and 40 , respectively. More specific details regarding the interface between the panels 30 and 40 and the bag 10 are discussed in greater detail below.
[0019] The panels 30 and 40 include inside surfaces 33 and 43 and outside surfaces 35 and 45 , respectively. The panels 30 , 40 include first end portions 31 and 41 (also referred to as lower portions), second end portions 32 and 42 (also referred to as upper portions), and locking mechanisms 34 and 44 disposed at the second end portions 32 and 42 . The inside and outside surfaces 33 , 35 of the panel 30 at the first end portion 31 are attached to the first major surface 20 of the bag 10 . Likewise, the inside and outside surfaces 43 , 45 of the panel 40 at the first end portion 41 are adhered to the first major surface 18 of the bag 10 . The panels 30 and 40 have a width Wp that is less than or equal to half of the length Lp of the peripheral edge 16 (see FIG. 4 ). In the embodiment shown, the length Lp of the periphery edge 16 is equal to twice the width Wb of the primary surface 20 of the bag 10 . In the embodiment shown, the difference between the width Wb of the primary surface 20 or 18 and the width Wp of the panel 30 or 40 is approximately the width Wo of the opening at the open end 16 of the bag 10 .
[0020] In use, the bag 10 is positioned by grasping the panels 30 , 40 such that the open end 14 of the bag 10 is centered over the waste 50 and end portions 32 , 42 of the panels 30 , 40 are positioned towards the closed end 12 of the bag. The scraping edges 36 and 46 as shown in FIG. 1 of the lower portions 31 and 41 of the bag 10 can be used to press the bag 10 against the contaminated surface S such that simultaneously rotating and moving together the first panel 30 and the second panel 40 in the direction shown by arrows 3 and 4 moves the edges 37 and 47 towards one another so as to engage and lift the waste 50 into the open end 14 of the bag 10 . Alternatively, one panel can be held stationary while the other is moved towards the stationary panel to scrape feces into the inner cavity of the bag 10 .
[0021] Once the waste 50 is in the bag 10 , the pet waste retrieval and storage bag 1 can be flipped over as shown in FIG. 2 . Flipping bag 10 from the position shown in FIG. 1 to the position shown in FIG. 2 causes the waste 50 to move from the open end 14 of the bag 10 to the closed end 12 of the bag 10 . In the flipping process the user can continue to rotate the panels 30 , 40 until they are engaged, thus closing the open end of the bag 10 . Once closed, the lower portions 31 , 41 of the panels 30 , 40 are disposed within the bag.
[0022] Now referring to FIG. 2 , a pet waste retrieval and storage bag 1 containing a piece of waste 50 is shown in a closed state. In the closed state, the first panel 30 is shown positioned adjacent the second panel 40 such that the outside surface 35 of the first panel 30 and the outside surface 45 of the second panel 40 are adjacent each other. The second ends 32 , 42 of the first and second panels 30 , 40 are disposed away from the bag 10 and, as discussed above, the first ends or lower ends 31 and 41 are disposed within the bag 10 . The orientation described above where the second ends 32 and 42 are internal to the pet waste retrieve and storage bag 1 is preferred because the portions of the bag 10 located at the lower ends 31 and 41 of the panels 30 and 40 are likely to be contaminated by the waste 50 as a result of direct contact with the waste 50 during the scraping and scooping process described above.
[0023] Still referring to FIG. 2 , the locking mechanism 38 is shown engaged. In the embodiment shown, the locking mechanism 38 is shown as tabs 34 and 44 that are partially cut portions located on the second end portions 32 and 42 of the panels 30 and 40 . The tabs 34 and 44 can be bent to one side or another in such a way that they engage and interlock to aid in keeping the open end 14 of the bag 10 closed.
[0024] Referring now to FIGS. 3 and 4 , the manufacturing process of the above-described pet waste retrieval and storage bag 1 is described in greater detail. Since the manufacturing process applicable for both sides of the pet waste retrieval and storage bag 1 is identical, the manufacturing step of only one side is described herein.
[0025] In the embodiment shown, a score line 26 is made in the bag 10 to aid in folding. The open end 14 of the bag 10 is cut along the edges 17 and 19 up to the score line 26 to form the flap 24 . A panel 30 having a width Wp that is less than the width Wb of the bag 10 is positioned with its scraping edge 36 along the score line 26 . The portion of the inside surface 33 near the first end portion 31 is glued or fused to the bag 10 . The flap 24 is then folded towards the panel 30 and glued or fused to the portion of the outside surface 35 near the first end portion 31 of the panel 30 . The same process is repeated for the second side 18 of the bag 10 using the panel 40 to complete the assembly process resulting in the pet waste retrieval and storage bag 1 shown in FIG. 3 .
[0026] With respect to the material used to construct the pet waste retrieval and storage bag 1 , it should be appreciated that various different materials other than plastic can be used in the construction of the bag 10 . For example, the bag 10 could be constructed of paper, paper with a wax treatment, or a cloth material lined or coated with a plastic material. In addition, the bag 10 shown is a flat bag, however, it should be appreciated that the bag may include gussets. Similarly, it should be understood that many other materials other than corrugated cardboard can be used in the construction of the panels 30 and 40 . For example, the panels can include plastic, wood, or other composite constructions. In the embodiment shown in FIGS. 6-9 , the panels 65 , 67 are shown constructed of plastic. The bag 70 shown in FIGS. 6-8 also includes slits 60 . The slits 60 enable the corners 64 of the bag 70 to fold in toward each other when the bag 70 is in the closed position as shown in FIGS. 8-9 .
[0027] In addition, it should be understood that though in the embodiment shown the bag 10 includes only two major surfaces 20 and 18 , which are connected at their periphery edges, other embodiments may include additional intermediate side surfaces used to connect the first and second major side surfaces 20 , 18 together.
[0028] Moreover, it should be understood that in some embodiments, pet waste retrieval and storage bag 1 does not include flap portions 22 , 24 . In these embodiments, the panels 30 and 40 are connected to the bag 10 only at their first major surfaces 33 and 43 . In addition, it should be understood that the panels 30 and 40 are not necessarily connected to the bag 10 with adhesives such as glue. In the embodiment shown in FIGS. 6-9 , the bag is fused or melted to the plastic panels 30 , 40 along fuse line 62 . In other embodiments, the panels 30 and 40 can be, for example, stapled, taped, sewn, heat sealed, or clipped to the bag 10 . Numerous additional means to attach the bag 10 to the panels 30 , 40 are possible.
[0029] In some embodiments the device is sized to be conveniently carried in ones purse or pockets. In such embodiments, the bag can be folded over the panels such that the overall length and width dimensions of the device are substantially the same as the length and width dimensions of the panels. In some preferred embodiments each panel has a surface area of less than 100 square inches and more preferably each panel has a surface area of less than 36 square inches.
[0030] The above specification, examples, and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. | The disclosure is directed to a sanitary collapsible pet waste retrieval and storage device that is simple and easy to operate. The device includes a bag and a pair of panels attached to opposing sides of the bag. The panels and bag are sized and configured such that rotating and moving scraping edges of the panels together scoops waste into the bag and positions the scraping edges within the bag. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Patent Application No. 10-2015-0054409, filed on Apr. 17, 2015 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a flow-type energy storage device and a reaction cell for use in the same, and more particularly to a flow-type energy storage device having improved flowability of fluid, and a reaction cell for use in the same.
[0004] 2. Description of the Related Art
[0005] Production costs of electric power have increased due to rapid changes in the prices of fossil fuels such as petroleum and coal, which are main raw materials used to produce electric power, unstable energy supply and demand attributable to rising exchange rates, and entry into the age of high oil prices and compulsory reduction of greenhouse gas emissions. Accordingly, national energy management, systems are required. Greenhouse gases, which are emitted from known energy sources using fossil fuel, serve as a main factor in the destruction of ecosystems and environmental pollution, and accordingly, new renewable energy, such as wind power, sunlight, and tidal power, has come into the spotlight as an alternative energy source for overcoming the destruction of ecosystems and environmental pollution. However, since electric power, which is produced using new renewable energy, is very vulnerable to changes in the weather, it is impossible to uniformly and constantly supply electric power. Therefore, there is a drawback in that new renewable energy sources are not capable of being directly connected to a known electrical grid system for use. In order to overcome this drawback, large and medium-sized energy storage devices are required. Large and medium-sized secondary batteries are also required in various other fields, such as green car and green home fields, in addition to the new renewable energy storage field.
[0006] A typical secondary battery includes an electrode active material and an electrolytic solution in a fixed amount, and accordingly, there is a limitation as to the extent to which energy storage capacity can be increased. In contrast, a currently developed flow-type energy storage device, which includes a fluidic material (an electroactive compound or a slurry electrode) storing energy, such as a redox flow battery (RFB) and an electrochemical flow capacitor (EFC), has a merit in that an energy storage amount may be significantly increased depending on the size of an external tank for storing the fluidic material.
[0007] In the redox flow battery and the electrochemical flow capacitor, a redox reaction or an electric double-layer forming process is performed in a reaction region containing the fluidic material in order to store electric energy. The reaction region is formed using a gasket, and is divided by a membrane which is positioned at an intermediate position thereof. The fluidic material stays in the reaction region to come into contact with a metal or graphite current collector or the wide surface of an electrode.
[0008] However, a current redox flow battery or electrochemical flow capacitor includes a gasket having a through hole having a tetragonal cross-section, and the contact surface of the electrode or the current collector with the fluidic material is tetragonal. The known reaction region having the aforementioned structure has a problem in that the slurry-type fluidic material including the electrolyte limitedly flows with regard to the electrode.
[0009] Technology for forming a plurality of inlets, through which a slurry-type fluidic material is injected into a reaction region, and widely dispersing the inlets, or technology for further providing a separate part to control the flow of a slurry fluidic material in a reaction region, has been developed in order to overcome the aforementioned problem. However, the technologies have drawbacks in that it is difficult to manufacture devices and in that the structures of the devices are complicated.
[0010] [Prior Art Document] 1. Korean Patent No. 10-1176559, and Korean Patent Application Laid-Open Nos. 10-2014-0095283 and 10-2015-0007750
SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an object of the present invention is to provide a flow-type energy storage device, which has improved flowability of fluid to thus maintain electrical properties even when charging and discharging are repeatedly performed, and a reaction cell for use in the same.
[0012] In order to accomplish the above object, the present invention provides a flow-type energy storage device for storing electricity using a highly viscous slurry-type fluidic material. The flow-type energy storage device includes a reaction region in which charge-discharge reaction of electricity is performed by the fluidic material, wherein the reaction region has an octagonal cross-section.
[0013] The term “flow-type energy storage device” used in the present specification includes all devices for storing electrical energy in the fluidic: material, such as a redox flow battery and an electrochemical flow capacitor.
[0014] In the present invention, a separate flow-control part is not used, and a plurality of inlets and outlets are not formed, but the cross-section of the reaction region, in which fluid remains, is changed to be octagonal in order to improve the flowability of the fluidic material used in the flow-type energy storage device. When a highly viscous slurry-type fluidic material is used, each corner of the tetragonal cell is sharp-angled having a small angle, thereby acting as a resistor of a slurry fluidic electrode to thus hinder the smooth movement of the fluidic material, thereby precipitating the electrode. Accordingly, the octagonal cross-section may be a design which minimizes resistance during fluidization.
[0015] It is preferable that an inlet, through which the fluidic material is injected into the reaction region, and an outlet, through which the fluidic material is emitted from the reaction region, be formed, and that the inlet and the outlet be disposed so that the fluidic material flows diagonally. Specifically, the inlet and the outlet are disposed left and right at upper and lower portions so that the fluidic material flows diagonally (in any one direction of and . With respect to the disposal, the inlet and the outlet may be formed at sides corresponding in position to corners of the reaction region having the tetragonal cross-section, which are removed in order to form the octagonal cross-section. When the fluidic material flows diagonally, the fluidic material more smoothly flows.
[0016] Further, it is preferable that the reaction region include an anode reaction region and a cathode reaction region, with a membrane positioned between the anode reaction region and the cathode reaction region, and that the inlet and the outlet be disposed in the anode reaction region and the cathode reaction region, respectively, so that diagonal flow directions of the fluidic material cross each other in the anode reaction region and the cathode reaction region. For example, the inlet and the outlet are disposed in each region so that the flow direction is or in the cathode reaction region when the flow direction is in the anode reaction region and the flow direction is or in the cathode reaction region when the flow direction is in the anode reaction region.
[0017] Moreover, it Is preferable that the inlet and the outlet be disposed so that the fluidic material flows upward in any one reaction region of the anode reaction region and the cathode reaction region and flows downward in a remaining reaction region. For example, the inlet and the outlet are disposed so that the flow direction is in the cathode reaction region when the flow direction is in the anode reaction region, the flow direction is in the cathode reaction region when the flow direction is in the anode reaction region, and the flow direction is or in the cathode reaction region when the flow direction is or in the anode reaction region. When the flow directions horizontally and vertically cross each other in the anode and cathode reaction regions, forces attributable to the flow of fluid, which are applied to the reaction cell, are offset, improving the balance and the stability of the reaction cell. Therefore, when a stack structure, which includes a plurality of stacked reaction cells, is formed, leaning of the stack structure attributable to the flow of fluid may be prevented.
[0018] In order to accomplish the above object, the present invention also provides a reaction cell for use in a flow-type energy storage device, the reaction cell including a reaction region in which charge-discharge reaction of electricity is performed by the fluidic material, wherein the reaction region has an octagonal cross-section.
[0019] The reaction region may be formed using a gasket, and a through hole, which is formed through the gasket, may have an octagonal cross-section to thus ensure the octagonal cross-section of the reaction region.
[0020] In addition, as described above, the inlet, through which the fluidic material is injected into the reaction region, and the outlet, through which the fluidic material is emitted from the reaction region, may be disposed so that the fluidic material flows diagonally. Particularly, it is preferable that the flow directions of the fluidic material cross each other in the anode reaction region and in the cathode reaction region. Particularly, the inlet and the outlet are constituted so that the four flow directions, which include upper, lower, left, and right directions, cross each other to thus offset forces attributable to the flow of fluid, which are applied to the reaction cell, thereby improving the balance and the stability of the reaction cell.
[0021] In the present invention having the aforementioned constitution, the shape of the reaction region is controlled to thus improve the flowability of the fluidic material, thereby providing a flow-type energy storage device which has almost constant electrical properties even when a charging and discharging cycle is repeatedly performed.
[0022] Further, in the present invention, the structures of the inlet and the outlet are not complicated and a separate part for controlling a flow of fluid is not used in the device, and accordingly, additional costs are not incurred during a process of manufacturing the flow-type energy storage device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0024] FIG. 1 is a mimetic diagram showing the constitution of a flow-type energy storage device;
[0025] FIG. 2 is an exploded perspective view showing the structure of a reaction cell according to an Example of the present invention;
[0026] FIG. 3 is a view showing the cross-sectional shape of a reaction region according to the present Example;
[0027] FIG. 4 is a graph showing the result of a charging and discharging experiment using a reaction cell of a Comparative Example;
[0028] FIG. 5 is a graph separately showing the experimental result of the third cycle of FIG. 4 ;
[0029] FIG. 6 is a graph showing the change in capacity of the reaction cell of the Comparative Example as a function of a charging and discharging cycle;
[0030] FIG. 7 is a graph showing the result of a charging and discharging experiment using the reaction cell of the present Example;
[0031] FIG. 8 is a graph separately showing the experimental result of the third cycle of FIG. 7 ; and
[0032] FIG. 9 is a graph showing the change in capacity of the reaction cell of the present Example as a function of a charging and discharging cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] A detailed description, will be given, of embodiments of the present invention, with reference to the appended drawings.
[0034] FIG. 1 is a mimetic diagram showing the constitution of a flow-type energy storage device.
[0035] A flow-type energy storage device 100 typically includes a storage tank 200 , storing a fluidic material, and a reaction cell 300 , including reaction regions 400 in which an electrical charging or discharging reaction of the fluidic material is performed. A known technology may be applied without any modification to the constitution of circulation of the fluidic material and the constitution of electrical connection to the outside with respect to the reaction, and accordingly, a detailed description thereof will be omitted.
[0036] FIG. 2 is an exploded perspective view showing the structure of a reaction cell according to an Example of the present invention.
[0037] The reaction cell 300 of the present Example includes end plates 310 , gas 320 , and a membrane 330 , and electric conductor plates 340 are provided on inner sides of the end plates 310 .
[0038] Specifically, the reaction cell 300 , the gaskets 320 and the end plates 310 are sequentially disposed on both sides of the membrane 330 . A through hole, which is formed through the gasket 320 , forms the reaction region 400 , in which the fluidic material, which stores or emits electricity, is contained. The electric conductor plate 340 , which is provided on the end plate 310 , constitutes one lateral surface of the reaction region 400 , and accordingly, the fluidic material comes into contact with the electric conductor plate 340 to perform electrical charging and discharging.
[0039] In the reaction cell 300 of the present Example, the reaction region 400 , which is formed using the gasket 320 , has an octagonal cross-section. Specifically, the octagonal cross-section has a truncated form obtained by removing four corners from the tetragonal cross-section of the reaction region of a known gasket. Due to the aforementioned structure, the fluidic material flows smoothly compared to the known reaction region having a tetragonal cross-section. Accordingly, a contact property between the fluidic material and the electric conductor plate 340 is improved to thus improve the performance of the flow-type energy storage device.
[0040] In the present Example, in addition to the through hole in the gasket 320 , the electric conductor plate 340 is formed in an octagonal shape in order to reduce material costs. However, as long as the electric conductor plate 340 has a size large enough to completely cover one side of the gasket. 320 , the electric conductor plate 340 may have other shapes, and the known tetragonal electric conductor plate 340 may be used.
[0041] Further, the electric conductor plate 340 , which serves as the electrode at a redox flow battery or the current collector of an electrochemical flow capacitor, typically includes a graphite material. In the present Example, a current collecting plate 350 including a metal material, which is charged with electricity or from which electricity is discharged to the outside, is further provided, in addition to the electric conductor plate 340 including the graphite material.
[0042] In addition, in order to improve the flowability of the fluidic material, an inlet 322 and an outlet 324 are positioned so that the fluidic material flows diagonally in the reaction region 400 . Specifically, the inlet 322 and the outlet 324 are formed at sides corresponding in position to corners, which are diagonal to each other, such as upper left and lower right corners or upper right and lower left corners, of the known reaction region having the tetragonal cross-section. Further, the inlet 322 and the outlet 324 are disposed at the upper left and lower right sides, respectively, in one reaction region, and at the lower left and upper right sides, respectively, in the other reaction region so that the flow directions of the fluidic material cross each other in the cathode and anode reaction regions. Due to the aforementioned structure, the fluidic material flows in through the upper left side and flows out through the lower right side in one reaction region, and flows in through the lower left side and flows out through the upper right side in the other reaction region if the flow directions of the fluidic material, which flows diagonally in the two reaction regions divided by the membrane 330 , are inverse with respect to the upper, lower, left, and right sides, the upper, lower, left, and right positions are not limited to the aforementioned structure, but may be changed.
[0043] Accordingly, when the diagonal flow directions of the fluidic material, which flows into the two reaction regions facing each other, are opposite each other and cross each other, forces attributable to the flow of fluid, which are applied to the reaction cell, may be offset to thus improve the balance and the stability of the reaction cell. The balance and the stability of the reaction cell are particularly important when a stack structure is formed. A single reaction cell is described in the present Example. However, a stack structure, which includes a plurality of stacked reaction cells, is generally used in practice, but has a problem in that the stack structure leans due to the flow of the fluidic material flowing through the plurality of reaction cells. The flow directions of the fluid, which flows through the two reaction regions constituting the reaction cell, are set to cross each other to thus prevent the occurrence of problems attributable to the flow of fluid even in a structure which includes many stacked reaction cells.
[0044] Particularly, the inlet 322 and the outlet 324 may be disposed at sides, which are obtained by removing the corners of the reaction region having the tetragonal cross-section of the known gasket, to thus make better use of space, and this disposal of the inlet and the outlet may be applied to replace the reaction cell of the redox flow battery or the electrochemical flow capacitor, which includes the known reaction region having the tetragonal cross-section.
[0045] Since known technological matters may be applied to the membrane 330 of the present Example, a detailed description thereof will be omitted.
[0046] Hereinafter, the electrical properties of the electrochemical flow capacitor, which includes the reaction cell according to the present Example, and the known electrochemical flow capacitor, which includes the reaction cell including the reaction region having the tetragonal cross-section, will be compared.
[0047] FIG. 3 is a view showing the cross-sectional shape of the reaction region according to the present Example.
[0048] The reaction region of the reaction cell according to the present Example is 10 cm in height and width. However, the cross-section of the reaction region of the present Example has a truncated form obtained by removing four corners from die tetragonal cross-section of the known reaction region. Each corner of the tetragon is removed so that the removed portion forms a right-angled triangle having a bottom side of 29.3 mm and a height of 29.3 mm, our sides, which include horizontal and vertical sides, of the octagon are each 41.4 mm in length, and sides, which diagonally face each other, are each 40.7 mm in length.
[0049] In the present Example, the area of the graphite current collector, which is exposed to the reaction region, is 78 cm 2 , the thickness of the gasket is 1 mm, and the volume of the reaction region is 7.8 cm 3 .
[0050] In the Comparative Example, the reaction region having the tetragonal cross-section, which is 5 cm in length and breadth, is provided, the area of the graphite current collector, which is exposed to the reaction region, is 25 cm 2 , the thickness of the gasket is 1 mm, and the total volume of the reaction region is 2 . 5 cm 3 .
[0051] In addition, the inlet and the outlet of the reaction region are positioned so that diagonal flow directions cross each other, as described above, in the present Example, and the inlet and the outlet are formed at centers of top and bottom sides of the tetragon in the Comparative Example.
[0052] In addition, MSP-20 and super-P, which were activated carbon, were mixed at a mass ratio of 7:3 for use as an electrode material of a slurry electrode, which is the fluidic material for storing electricity in the electrochemical flow capacitor. The electrode material and an electrolytic solution were mixed at a mass ratio of 1:9 to manufacture the slurry electrode.
[0053] The flow rate of the slurry electrode was set to 300 ml to perform a charging and discharging experiment with a current density of 10 mA/cm 2 .
[0054] FIG. 4 is a graph showing the result of a charging and discharging experiment using the reaction cell of the Comparative Example, and FIG. 5 is a graph separately showing the experimental result of the third cycle. FIG. 6 is a graph showing the change in capacity of the reaction cell of the Comparative Example as a function of a charging and discharging cycle.
[0055] From FIGS. 4 and 6 , it can be confirmed that the life of a single cycle is shortened and the capacity is reduced as the charging and discharging cycle is repeated. Further, it can be confirmed that the IR drop and the over-potential shown in FIG. 5 are increased as the charging and discharging cycle is repeated, as in FIG. 4 . The aforementioned result is considered to be attributable to the fact that the slurry electrode, which flows into the reaction cell of the Comparative Example, is not totally flows out, but partially remains in the reaction region.
[0056] FIG. 7 is a graph showing the result of the charging and discharging experiment using the reaction cell of the present Example, and FIG. 8 is a graph separately showing the experimental result of the third cycle. FIG. 9 is a graph showing a change in capacity of the reaction cell of the present. Example as a function of the charging and discharging cycle.
[0057] Unlike the result of the reaction cell or the Comparative Example, it can be confirmed that the cycle life and the capacity are not changed and that the IR drop and the over-potential are almost constant even though the charging and discharging cycle repeated when the reaction cell of the present Example is used. This is because the slurry electrode smoothly flows into the reaction region and smoothly flows out from the reaction region, unlike in the Comparative Example.
[0058] Therefore, in the present. Example, the shape of the reaction region, into which the fluidic material flows, is changed to induce smooth flow of the fluid, thereby exhibiting stable charging and discharging efficiency even when the charging and discharging cycle is repeatedly performed.
[0059] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | Disclosed is a flow-type energy storage device having an improved flow of fluid. The flow-type energy storage device stores electricity using a fluidic material, and includes a reaction region in which charge-discharge reaction of electricity is performed by the fluidic material, wherein the reaction region has an octagonal cross-section. The shape of the reaction region is controlled to thus improve the flowability of the fluidic material, thereby providing a flow-type energy storage device that has almost constant electrical properties even when a charging and discharging cycle is repeatedly performed. Further, the structures of an inlet and an outlet are not complicated and a separate part for controlling the flow of fluid is not used in the device, and accordingly, additional costs are not incurred during a process of manufacturing the flow-type energy storage device. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
Priority to the filing date of U.S. provisional patent application Ser. No. 60/342,198 filed on Dec. 19, 2001 is hereby claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
The invention disclosed herein was supported by NASA Grant No. NCC3-511 through the Center for Space Power and Advanced Electronics of the Auburn University Space Power Institute. The U.S. Government has certain rights in the invention.
TECHNICAL FIELD
This invention relates generally to power semiconductor devices and more specifically to power semiconductor devices in which graded junction termination extensions (GJT) are formed to increase the breakdown voltage of the device, and to processes for fabricating same.
BACKGROUND OF THE INVENTION
Junction termination extensions (JTEs) and graded junction termination extensions (GJTEs) have been utilized as a device edge passivation technique in high voltage simiconductor devices such as MOSFETs, IGBTs, MCTs, bipolar transistors, thyristors, and diodes. In such devices, the maximum reverse voltage that the device can withstand is limited by the breakdown voltage of the reverse-blocking junction. However, the actual breakdown voltage of the junction normally falls short of the breakdown voltage that might ideally be achieved because of the development of excessively high field strengths at the termination of the junction between the P region and the N region, usually at a location slightly above the metallurgical junction along a region of curvature at the junction termination. The formation of JTEs that overlap and extend laterally from such junctions act to spread the high field strengths over wider areas and thereby increase the voltage at which avalanche breakdown occurs.
Various techniques, generally employing well known masking, doping, and diffusion processes, have been developed for forming JTEs and GJTEs in semiconductor devices, such as diodes, that are formed on silicon substrates. U.S. Pat. Nos. 4,927,772 of Arthur et al., 4,648,174 of Temple et al., and 6,215,168 of Brush et al. all disclose and discuss examples of such techniques and the disclosures of these patents are hereby incorporated by reference. Traditional masking, doping and diffusion techniques work well with semiconductor devices fabricated on silicon because dopants applied to the silicon diffuse into the silicon with relative ease at reasonable temperatures. As a result, the formation of JTEs and GJTEs in silicon-based semiconductor devices has become standard practice, particularly in higher voltage devices.
Materials other than silicon have been demonstrated to exhibit characteristics superior to silicon as a substrate in high power semiconductor devices. One such material is silicon carbide (SiC). An attractive property of SiC is that its critical field strength is over ten times that of silicon. For a given voltage rating, this high field strength translates to a two to three order of magnitude reduction in the specific on-resistance of the drill region of an SiC power device. Unfortunately, just as in silicon devices, ideal blocking voltage is difficult to achieve due to effects at the device edge. For planar devices, field line crowding causes the electric field to be higher at the perimeter than in the bulk of the device. This field crowding can cause increased leakage current and ultimately premature breakdown of the device. Field line crowding can be reduced with etched mesa isolation; however, damage from etching can also cause leakage and premature breakdown at the device edges.
Many techniques have been employed to remedy this periphery problem. Guard rings, field plates, argon implantation, and junction termination extensions (JTEs) have been used for planar SiC devices. Beveled sidewalls and multiple step etching, as well as JTEs, have been used for mesa-isolated devices. These methods have been successful for the most part, but each method has its particular drawbacks. Guard rings are often difficult to fabricate; field plates are limited by the strength of the dielectric used; argon implantation can increase reverse leakage current; beveled etching is less effective with abrupt, one-sided negative junctions, and multiple step etching complicates the beveling process with additional fabrication steps. Junction termination extensions have been widely used, but JTEs are difficult to optimize and implement with a SiC substrate and GJTEs, which require multiple zones of decreasing implant dose in order to achieve ideal breakdown for a junction, are even more difficult to implement. These difficulties are due in large measure to the fact dopants do not diffuse into the SiC substrate material as they do into silicon, except at extremely high temperatures that tend to destroy the SiC material itself. More specifically, the combination of implantation/diffusion is not feasible for SiC because almost all atoms have extremely low diffusion coefficients in SiC at temperatures below 2,000° C., which is very nearly the bulk growth temperature of SiC itself. Thus, traditional masking, implantation, and diffusion techniques typically used to create JTEs and GJTEs in silicon-based semiconductor devices simply are not available for use in SiC-based semiconductor devices.
Accordingly, a need exists for reliable techniques and methodologies for forming JTEs and GJTEs in semiconductor devices utilizing materials other than silicon, such as SiC, in order to take full advantage of the superior performance of such materials in high voltage semiconductor devices. It is to the provision of such techniques that the present invention is primarily directed.
SUMMARY OF THE INVENTION
The properties of silicon carbide as compared to silicon makes silicon carbide an ideal semiconductor material for high power devices. In comparing the suitability of a silicon or a silicon carbide device having the same geometries and size, the silicon carbide device should be able to handle much higher power levels. The power level is basically the product of the voltage that the device experiences and the current that the device carries. Thus, for example, a single SiC transistor may handle the same current at a particular voltage as four or five large silicon transistors. Basic properties of SiC materials, such as band gap, thermal conductivity, saturated electronic drift velocity, and critical breakdown field, also favor silicon carbide over silicon. Silicon carbide also is a much more robust material when dealing with high voltages and high currents that produces substantial heat in a device that must be dissipated. The heat can be dissipated away from the silicon carbide device much quicker than a silicon device because of the silicon carbide device's thermal conductivity. Furthermore, the band gap in silicon carbide is approximately three times that of the band gap in silicon. Thus, the silicon carbide device will maintain its semiconductor characteristics up to much higher temperatures. Junction breakdown voltage decreases as doping level increases. Breakdown voltage is also a function of the radius of curvature of the junction space-charge region. For high power devices, whether made of silicon or silicon carbide, a junction termination extension is needed to prevent breakdown due to field line crowding at the periphery of the active area of the device.
The present invention provides a graded junction termination extension (GJTE) that is self-aligning to simplify the ion implementation process during fabrication, thereby reducing production costs for electronic devices such as power semiconductor devices. The novel graded junction termination extension and method of fabrication produces an implanted dopant distribution that varies in concentration moving away from the edge of the active area of a device.
Briefly described, the present invention, in a preferred embodiment thereof, is directed to graded junction termination extensions that are very effective in increasing the breakdown voltage of implanted silicon carbide (SiC) junction diodes. This technique can easily be used to terminate other devices such as Schottky diodes, bipolar junction transistors, or thyristors. The key to making a GJTE is the fabrication of a graded photoresist mask that is used to create a carbon implant mask, or as an etch mask for making an oxide implant mask. Of the methods described here, the defocused lithography pattern is the preferred method for grading photoresist masks. Exposing the photoresist with a sufficient gap between the lithography mask and the photoresist is only one way to blur the pattern. If a wafer stepper is available for patterning, the pattern can simply be defocused before exposing the photoresist in order to create the same edge blurring effect. In addition, a gray-scale lithography mask can be used to bevel the edge of the photoresist. With this mask, a light intensity gradient is designed into the mask itself. Once the process is established for a given application and fabrication process, the GJTE is a very effective, cost-efficient method for power device termination.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is better understood by reading the following detailed description of an exemplary embodiment in conjunction with the accompanying drawings.
FIG. 1 illustrates a thickness profile for a graded carbon implant mask measured with a stylus profilometer.
FIG. 2 illustrates a TRIM implant profile simulation showing dopant concentrations of the anode region and the GJTE region at the perimeter of the anode.
FIG. 3 illustrates a breakdown voltages for p-n diodes as measured in Florinert.
FIG. 4 illustrates a reverse current density versus applied voltage for implanted SiC p-n diodes with and without GJTE termination.
FIG. 5 illustrates forward current-voltage characteristics of an 1800 V SiC p-n diode fabricated with a graded junction termination extension.
FIG. 6 illustrates thickness profiles for SiO 2 films etched with four different photoresist etch masks.
FIG. 7 illustrates a cross-section of a compound photoresist mask used for reactive ion etching of an SiO 2 implantation mask.
DETAILED DESCRIPTION OF THE INVENTION
The following description of the invention is provided as an enabling teaching of the invention in its best, currently known embodiment. Those skilled in the relevant art will recognize that many changes can be made to the embodiment described, while still obtaining the beneficial results of the present invention. It will also be apparent that some of the desired benefits of the present invention can be obtained by selecting some of the features of the present invention without utilizing other features. Accordingly, those who work in the art will recognize that many modifications and adaptations to the present invention are possible and may even be desirable in certain circumstances, and are a part of the present invention. Thus, the following description is provided as illustrative of the principles of the present invention and not in limitation thereof, since the scope of the present invention is defined by the claims.
Junction termination extension (JTE) is one of several passivation techniques used with power semiconductor devices to prevent breakdown due to field line crowding at the periphery of the active area of the device. All semiconductor power devices have passivation of some kind. Device performance (e.g., higher breakdown voltage) can be significantly improved using proper JTE procedures, and the fabrication of junction termination extensions that have graded implant concentrations as one moves away from the active region of a semiconductor device. By graded, it is meant that the concentration of implanted dopant atoms (i.e., the number of atoms/cm 3 ) decreases with distance from the periphery of the active region. This grading is produced by using a mask set for implantation that has patterns of different shape and size according to the distance from the edge of the device active area. All of the remaining device area adjacent to the active area is not implanted, rather only selected portions of the remaining area that are exposed by the openings in the mask set. Implantation is carried out at several different energies with one or more doses at each energy; however, all of the open patterns in the mask set are implanted identically. A graded concentration is then achieved by heating the sample, usually silicon, to diffuse the implanted species. The combination of diffusion and the pattern of the open areas in the mask set determines the spatial variation of the implanted dopants as one moves away from the edge of the active area of the device.
The present invention describes a graded junction termination extension (GJTE) process usable with SiC semiconductor devices that is effective and self-aligned to simplify the ion implantation process during fabrication so as to potentially reduce production costs for electronic devices such as power semiconductor devices. The new type graded junction termination extension and method of fabrication disclosed herein produces implanted dopant distributions that vary in concentration and depth as one moves away from the edge of the active area of the device. The effectiveness of this new graded junction termination extension has been demonstrated in the fabrication of implanted p-n junction diodes where the application of the GJTE improves breakdown voltage by more than a factor of two compared to diodes that were not terminated. Details of the GJTE fabrication process and the preliminary results achieved are described in more detail below.
The material used in GJTE experiments is available from Cree, Inc., and includes an n + 4H-SiC substrate with a 10 μm n − epitaxial layer doped at 4.6×1015 cm −3 . A carbon mask for implanting the anodes and the diodes was fabricated as follows. An AZ® 5214-E positive photoresist manufactured by Clariant was spun onto a 5 mm by 5 mm square piece of material at 400 rpm for 30 sec. The sample was then baked in an oven at 90° C. for 90 min. The photoresist was exposed through a dark field mask having a window diameter of 312 μm for 45 sec to ultraviolet (UV) light from a 160 W mercury (Hg) lamp. Exposure was performed with the photoresist surface separated from the mask by a few millimeters. This was accomplished by setting the stage on a Karl Suss MJB3 photo mask aligner to its lowest position before exposure. The sample was then developed for 2 min. in Microposit H 2 O:351 (3:1) developer available from Shipley Company, Inc. Exposing the sample with the mask away from the surface of the photoresist causes the light at the perimeter of each circular window to be out of focus. For a positive photoresist, the rate at which the photoresist is dissolved in the developing solution is proportional to the amount of light absorbed during exposure. Therefore, instead of the usual well-defined vertical step, the edges of the photoresist are gently sloped.
After another bake in the 90° C. oven for about an hour, the photoresist pattern had a thickness of about 6.9 μm away from the sloped edges. The spin speed and baking procedures provided herein are far different from those recommended by the manufacturer since the photoresist used in this experiment is designed for much thinner applications and was used simply because of availability. Other, thicker photoresists can be used to produce a similar mask pattern with much less difficulty. A carbon strip furnace was then used to anneal the sample in flowing argon (Ar). During the anneal, the temperature was increased at an average rate of about 60° C./mm to 1000° C. where it was then held for 10 min. This anneal converted the photoresist into a carbon film with a thickness averaging about 1.2 μm. Annealing vacuum instead of argon was found to produce similar, but slightly thinner carbon films. A profile of the carbon film taken at the edge of a circular window is shown in FIG. 1 . The ordinate (y-axis) is carbon layer thickness. The abscissa (x-axis) is distance from the edge of the circular window that defines the active area of the device.
In order to simulate implant profiles using the software package TRIM, the density of the carbon film had to be determined. This was accomplished using Rutherford Backscattering Spectrometry (RBS) techniques. A density of 1.475 gm/cm 3 was determined by adjusting the density used in the simulation until the carbon thickness derived from the RBS data matched the thickness obtained using a stylus profilometer. Once the density has been determined for a particular carbon film fabrication process, the RBS analysis need not be repeated.
Because of difficulty producing low energy ions with the accelerator used for implantation, a 90 nm molybdenum (Mo) layer was sputtered over the entire sample to bring the minimum energy ions to the surface of the SiC. Aluminum (Al) ions were implanted at 700° C. with multiple energies ranging from 170 to 525 keV to produce a box profile anode region with a maximum concentration of 2×10 19 cm 3 . Along the perimeter of the anodes, however, the implant took on a profile similar to that of the carbon implant mask. FIG. 2 depicts a TRIM implant profile simulation showing dopant concentrations of the anode region and the GJTE region at the perimeter of the anode. Spatially, the depth of the implanted region tapered off to zero around 100 μm from the edge of the anode region. Also, note in FIG. 2 that the concentration in the extension region also decreases gradually as the extension extends laterally from the edge of the anode region.
After ion implantation, the Al ions were activated by annealing at 1700° C. for 30 min. in flowing argon at slightly above atmospheric pressure. The sample was annealed in a SiC box that contained a small amount of Si to prevent preferential sublimation of Si from the SiC surface. Before annealing, the Mo implant mask layer was chemically etched away. The carbon mask layer was removed using an oxygen plasma. For samples annealed with the carbon mask layer in place, it was discovered that high temperature annealing in the presence of silicon grows SiC on the surface of the carbon film, making removal very difficult. Following activation, anode and cathode contacts were fabricated from Al 90 Ti 10 and Ni 93 V 7 alloys, respectively. Both contacts were annealed with one three minute, 1000° C. anneal in a vacuum. The anode contact area was 7.26×10 −4 cm 2 . Another sample with a vertical wall Mo implant mask was processed with the GJTE sample as a control reference. Neither sample had a thermal or deposited oxide for passivation.
Reverse breakdown measurements were first taken at room temperature in Florinert, an inert organic liquid, using a Tektronix 371A curve tracer. Out of the thirty-five devices fabricated on each 5 mm×5 mm sample, the GJTE and the control samples yielded twenty-six and twenty-four working devices, respectively. For the GJTE sample, breakdown voltages ranged from 630 V to 1770 V and averaged 1380 V. Breakdown voltages for the control samples ranged from 360 V to 624 V and averaged 537 V. FIG. 3 shows the distribution of breakdown voltages for p-n diodes as measured in Florinert for both samples. Each column represents the breakdown voltage of one diode. After testing the devices on the curve tracer, one of the best devices from each of the two die was then tested with a system that stepped the reverse voltage in ten-volt increments until breakdown was observed. Testing in this manner produced somewhat higher breakdown voltages than were obtained with the curve-tracer, where the voltage was swept continuously. The maximum breakdown voltage increased from 1770 V to 1830 V for the GJTE device and from 624 V to 939 V for the control device. Numerical simulations made with MEDICI device simulator software from Avanti predicted a breakdown voltage of 1900 V for an ideal planar device with a 9 μm drift layer of the same concentration. Reverse current-voltage measurements for the two devices are shown in FIG. 4 . The lack of data points at lower voltages for the GJTE device indicates that currents at these voltages were below the measurement threshold of the system. Forward current-voltage characteristics revealed no distinct differences between the GJTE sample and the control sample. As illustrated in FIG. 5 , forward current-voltage (I-V) measurements for a typical GJTE device showed a turn-on voltage of approximately 2.8 V and an ideality factor of 1.3 in the range from about 1×10 −3 to 2 A/cm 2 .
Breakdown voltages for the GJTE devices approach ideal (as determined by numerical simulation) with an average breakdown voltage over 2.5 times the average of the control devices. Thus, it appears that the graded junction termination extensions are very effective in preventing premature edge breakdown. With conventional JTEs, detailed calculations based on an accurate knowledge of the activated dopant concentration are normally required. No such calculations were performed in the design of the GJTE diodes described herein. Calculations were required only to ensure that the carbon layer was thick enough (i.e., maximum thickness) to block all of the implanted ions. This flexibility is the result of the implant depth contour and the implant concentration gradient shown in FIG. 2 .
Other methods for fabricating a GJTE were explored in addition to the carbon mask. Techniques for making a graded SiO 2 implant mask were developed first. In fact, using SiO 2 probably is preferred over carbon since processes for readily depositing SiO 2 films are already in widespread use in the semiconductor industry.
The basic approach for making an SiO 2 GJTE mask starts with deposition of a thick oxide layer that blocks the highest energy ions used during implantation. A graded photoresist layer is then deposited and used as a mask for etching the SiO 2 . During reactive ion etching of the oxide film, the graded portion of the photoresist is gradually etched away. As more oxide surface is exposed to the ionized etching gas, the profile of the SiO 2 begins to resemble that of the photoresist. FIG. 6 shows the profiles of four different SiO 2 films etched with different photoresist masks. The sample represented by curve (a) was etched with an AZ5214 mask that was prepared using procedures that were described previously for the carbon film mask. However, the photoresist was spun on at 1000 rpm instead of 400 rpm, after which the sample was baked on a 114° C. hot plate for 2.5 min. The same exposure conditions were used, and the developed sample was baked in a 90° C. oven for 2 hours. At this point, the photoresist had a maximum thickness of around 3.5 μm. All four of the samples in FIG. 6 were exposed a short time prior to etching in an oxygen plasma in order to remove any residue left on the exposed SiO 2 after developing. Etching was carried out at 13.6 MHz in flowing NF 3 at approximately 65 mTorr. The RF power supply was set at 18 W, giving a power density of about 0.5 W/cm 2 . The RF electrode was cooled with chilled water (˜10° C.). These conditions produced an SiO 2 etch rate of about 70 nm/min, and a photoresist rate of around 250-260 nm/min. Other etch gas chemistries can be used to etch the SiO 2 . Pure NF 3 was used here simply because it was available. Oxygen could be added to the etch gas to speed the photoresist etch rate steeper etch profiles. The profile can also be adjusted by changing the speed at which the photoresist is spun on. This is illustrated by curve (b) in FIG. 6 . Sample (b) had an AZ5214 photoresist spun on at 4000 rpm and was exposed for 30 sec with the same mask/substrate spacing used to produce curve (a). The photoresist thickness for these conditions was around 1.6 μm.
Beveled implant masks were also produced without exposing the photoresist with the mask/substrate gap mentioned above. The nearly linear profile represented by curve (c) in FIG. 6 was obtained with a sample etched with a mask of Microposit STR® 1045 photoresist. The STR 1045 photoresist is much thicker and softer than the AZ5214 photoresist. The photoresist was spun on at 4000 rpm for 30 sec and baked for 1.5 min at 100° C. The sample was exposed for 30 sec at 160 W with the mask in contact with the photoresist surface. A H 2 O:351 (4:1) solution was used for developing. The sample was transferred to a 2″ silicon wafer on a hot plate (˜200° C.) and then baked for about 10 min. on the hot plate at 100° C. The post-develop bake caused the STR1045 photoresist to flow and thus create a beveled profile at the edges. The photoresist at this point was about 5.5 μm thick. Etching for sample (c) was conducted with the same parameters used for samples (a) and (b).
Another graded photoresist etch mask was developed by inverting a method developed previously for etching beveled SiC mesas. A thick (˜7 μm) layer of Nano™ XP SU-8 25 negative photoresist was applied and patterned with 450 μm diameter holes. SU-8 is a thick negative photoresist that is very durable when cured. Subsequently, AZ5412 was spun on at 3000 rpm over the SU-8 and baked on a hot plate at 115° C. for 2 min. Smaller diameter holes were then opened inside the 450 μm openings in the SU-8. The exposure for this sample was conducted with the lithography mask in contact with the sample. After developing, this etch mask was used to create the SiO 2 profile represented by curve (d) in FIG. 6 . Exposing with a gap between the lithography mask and the substrate, as was the case for curve (a) and curve (b), would have smoothed out the steep shoulder seen within the first 10 μm of the profile. Surface tension between the SU-8 and the thinner, positive photoresist causes the thinner photoresist to creep up the SU-8 wall, thus producing a graded profile as illustrated in FIG. 7. A slower spin speed for the AZ5214 or possibly using a thicker photoresist such as the STR1045 would have made this effect more pronounced. However, the profiles produced with this method were not as uniform as those produced with the other methods disclosed.
All of the techniques described herein can also be used to make a graded ion implantation mask from materials other than SiO 2 . Polycrystalline silicon would likewise be a good material to use since procedures for depositing and reactive ion etching with this material are also well established.
The corresponding structures, materials, acts, and equivalents of any mean plus function elements in any claims are intended to include any structure, material or acts for performing the function in combination with the other claimed elements as specifically claimed.
While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various other changes in form and detail may be made without departing from the spirit and scope of the invention. | A graded junction termination extension in a silicon carbide (SiC) semiconductor device and method of its fabrication using ion implementation techniques is provided for high power devices. The properties of silicon carbide (SiC) make this wide band gap semiconductor a promising material for high power devices. This potential is demonstrated in various devices such as p-n diodes, Schottky diodes, bipolar junction transistors, thyristors, etc. These devices require adequate and affordable termination techniques to reduce leakage current and increase breakdown voltage in order to maximize power handling capabilities. The graded junction termination extension disclosed is effective, self-aligned, and simplifies the implementation process. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a tool-less fastener, for use in connecting a computer cable to one of a computer port connection and a peripheral port connection. It comprises an elongated rod having a central axis, a first end, and a second end; means for axially biasing the rod which is disposed proximate to the first end; means for restricting axial movement which is disposed proximate to the second end; and a resilient sleeve having an interior recess therethrough that is suitably sized to accommodate the rod and has a relaxed maximum outer transverse dimension that is less than the smallest transverse dimension of the elongated receiving recess. The sleeve is disposed around the rod between the means for axially biasing and the means for restricting axial movement.
The means for axially biasing is movable between a first position in which the sleeve is relaxed having a first pressure that does not substantially exceed a nominal compressive pressure applied to the sleeve by the means for axially biasing and a second position in which a deforming compressive pressure is applied to the sleeve by the means for axially biasing. The deforming compressive pressure compresses the sleeve axially and expands at least a portion of the sleeve radially relative to the central axis of the rod to a deformed maximum outer transverse dimension that is greater than the smallest transverse dimension of the elongated receiving recess.
There is a need for a reliable, efficient and simple means to secure the cabling between a computer and its various peripherals, whereby a functional system is completed. Existing technology for a cable connector utilizes a screw connection with a threaded borehole on the computer port connection or the peripheral port connection, and a rotatable screw integral with the cable holder. Often the space available to work at making the connections is severely limited and it is difficult if not impossible to turn the screw to make the connection.
To alleviate this problem, and others which will become apparent from the disclosure which follows, the present invention conveniently provides for a tool-less cable fastener. The present invention eliminates the need for tools and eliminates the need to have visual contact with the connection site. And it is possible to make the connection even where the space available to work at making the connections is severely limited. Once electrical connectivity is established, a flip of the lever arm establishes a physical interlock. The tool-less fastener of the instant invention is reliable, reusable and efficient.
In a preferred embodiment of the tool-less fastener of this important invention, the following components are provided: an elongated rod, with dimensions that will vary with application; attached to the rod is a lever mechanism that will rotate to a locking position due to a cam action and a flat surface incorporated on to the face of the lever; and a cupped washer that allows free travel over the outside diameter of the rod selected for the application. This washer is placed on the rod with the concave surface of the cup facing an elastic sleeve. The elastic sleeve is sized to fit closely over the outside diameter of the rod and of a length extending between two washers. The cupped spring washer may be pressed over an end of the rod until it snaps in place in a circumferential groove. This washer is placed on the rod with the concave surface of the cup facing the elastic sleeve.
The movement of the lever and the subsequent cam action will result in compression of the elastic sleeve between the two washers. A flat section incorporated on the peripheral edge of the lever mechanism can serve to lock the lever in place. The compression causes the elastic sleeve to expand inside of a smooth, threaded, or radially ribbed recess in which it is placed. This results in locking the intended cable in place.
A modular design for this fastener will allow for the custom assembly of the fastener as needed by an end user through stocking of a variety of components to have on hand.
The design allows for simple integration into existing cable manufacturing platforms. The design is also compatible with existing cable replacement applications.
Another advantage of having a tool-less fastener of the type disclosed herein is that there is no loose hardware that can be dropped into a conductive environment and cause component failure or binding of mechanical components such as a cooling fan blade.
These together with other objects of the invention, along with 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 the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
Still other advantages will be apparent from the disclosure that follows.
SUMMARY OF THE INVENTION
The present invention relates to a tool-less fastener for use in connecting a computer cable to one of a computer port connection and a peripheral port connection. An elongated rod having a central axis, a first end, and a second end is provided, along with means for axially biasing the rod which is disposed proximate to the first end. Furthermore, means for restricting axial movement which disposed proximate to the second end and a resilient sleeve having an interior recess therethrough that is suitably sized to accommodate the rod are taught.
The resilient sleeve has a relaxed maximum outer transverse dimension that is less than the smallest transverse dimension of the elongated receiving recess. The sleeve is disposed around the rod between the means for axially biasing and the means for restricting axial movement.
The means for axially biasing is movable between a first position in which the sleeve is relaxed having a first pressure that does not substantially exceed a nominal compressive pressure applied to the sleeve by the means for axially biasing and a second position in which a deforming compressive pressure is applied to the sleeve by the means for axially biasing. The deforming compressive pressure compresses the sleeve axially and expands at least a portion of the sleeve radially relative to the central axis of the rod to a deformed maximum outer transverse dimension that is greater than the smallest transverse dimension of the elongated receiving recess. The tool-less fastener may be independent of or integral with the holder of the computer cable.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are described hereinafter with reference to the accompanying drawing wherein:
FIG. 1 is a cut-away exploded perspective view of a first preferred embodiment of the tool-less fastener of the present invention showing the central rod with a circumferential recess disposed on one end and a transverse borehole on the other end for receiving a cam shaft, and with a second washer disposed around the shaft and a cylindrical sleeve disposed away from the rod adjacent to a first washer, and further showing a cam mechanism that can be secured to the rod by a camshaft and further showing a cable connection holder with a hole for receiving the resilient sleeve;
FIG. 2 is a cut-away perspective view of the first preferred embodiment of the tool-less fastener of FIG. 1, with the fastener inserted in the hole of the connection holder of the computer cable and the elongated receiving recess of the computer port connection, and with the cam wheel disposed in a second position whereby compressive forces are applied to the sleeve to secure same within said hole and recess;
FIG. 3 is a side elevation view of the tool-less fastener of the first preferred embodiment of the present invention disposed in a first position where the sleeve, disposed in a peripheral port connection recess and the hole of the connection holder, is relaxed;
FIG. 4 is a side elevation view of the tool-less fastener of the first preferred embodiment of the present invention with the cam disposed in the second position whereby the sleeve is compressed axially and expanded radially to effectuate a connection between the hole of the holder and the recess of the peripheral port connection to secure the cable to the associated peripheral;
FIG. 5 is an cut-away exploded perspective view of a second preferred embodiment of the tool-less fastener of the present invention showing the central rod with circumferential recess disposed on one end and a transverse bore hole on the other to receive a cam shaft, a second washer disposed around the shaft, a cylindrical sleeve disposed away from the rod adjacent to a first washer, and further showing a cam mechanism that can be secured to the rod by a camshaft also shown as a cable connection holder with a hole for receiving the resilient sleeve;
FIG. 6 is a cut-away perspective view of a second preferred embodiment of the tool-less fastener of FIG. 5 with the fastener connected to the connection holder of the computer cable and extending therefrom to the elongated receiving recess of the computer port connection and with the cam wheel disposed in the second position whereby compressive forces are applied to the sleeve to secure same within said recess, to secure the cable to the computer;
FIG. 7 is a side elevation view of a the tool-less fastener of the second preferred embodiment of the present invention disposed in a first position where the sleeve is relaxed;
FIG. 8 is a side elevation view of the tool-less fastener of the second preferred embodiment of the present invention with the cam disposed in the second position whereby the sleeve is compressed axially and expanded radially to effectuate a connection between the fastener extending from the holder and the recess of one of the peripheral port connection and the computer port connection to secure the cable to the object;
FIG. 9 is a side elevation view of a third preferred embodiment of the tool-less fastener of the present invention showing the sleeve disposed between a first and second washer with the second washer being retained in place relative to the rod by a bolt threaded to the rod;
FIG. 10 is a cut-away view of a cupped washer of the present invention viewed in perspective from the convex side;
FIG. 11 is a perspective view of a cupped washer of the present invention showing a central aperture of the washer with a plurality of inwardly directed radial fins;
FIG. 12 is a side elevation view of a preferred embodiment of the elongated rod of the tool-less fastener of the present invention showing an elongated rod with the circumferential groove disposed about the second end of said rod for accommodating a washer;
FIG. 13 is a side elevation of another preferred embodiment of the elongated rod of the tool-less fastener of the present invention showing the rod having a taper extending along at least one segment of its length tapering toward the first end of the rod;
FIG. 14 is a side elevation of another preferred embodiment of the elongated rod of the tool-less fastener of the present invention showing a shoulder of increased radial dimension disposed proximate to the second end thereof;
FIG. 15 is a side elevation view of the another preferred embodiment of the elongated rod of the tool-less fastener of the present invention showing the rod as cylindrical in shape with a first flattened end and a second flattened end, further showing the disposition of a first washer and a second washer both relative to said flattened ends, respectively;
FIG. 16 is a top plan view taken along the line 16 — 16 of FIG. 15 showing a notched central aperture with maximum transverse dimension greater than any maximum transverse dimension of the flattened end of the rod;
FIG. 17 is a top plan view of the cam mechanism showing a parallel set of cam wheels and a lever arm extending from the parallel set of cam wheels;
FIG. 18 is a side elevation view of the cam mechanism of FIG. 17 showing a peripheral edge with the first segment having a constant radius of curvature and a second segment of varying radii of curvature relative to the cam hole, said cam wheels being of a suitable size to allow it to be grasped between the fingertips of the user;
FIG. 19 is a top plan view of another preferred embodiment of the cam mechanism of the present invention showing a parallel set of cam wheels and a lever arm extending from the parallel set of cam wheels, said lever arm having a flattened profile, preferably with parallel surfaces, of a suitable size to allow it to be grasped between the fingertips of the user;
FIG. 20 is a side elevation view of the preferred embodiment of the cam mechanism of FIG. 19 showing a parallel set of cam wheels and a lever arm extending from the parallel set of cam wheels, said lever arm having a flattened profile, preferably with parallel surfaces, of a suitable size to allow it to be grasped between the fingertips of the user;
FIG. 21 is a perspective view of another preferred embodiment of the cam mechanism of the present invention showing a parallel set of cam wheels and an extensible lever arm extending from the parallel set of cam wheels; and
FIG. 22 shows a perspective view of a belleville washer of the tool-less fastener of the present invention from the concave side which may be employed in the tool-less fastener of the present invention.
FIG. 23 is a side elevation view of a preferred embodiment of the elongated rod of the tool-less fastener of the present invention showing an elongated rod with means for restricting axial movement integrally disposed proximate to the second end of the rod.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments depicted in the drawing include a tool-less fastener, for use in connecting a computer cable to one of a computer port connection and a peripheral port connection.
The discussion that follows, without limiting the scope of the invention, will refer to the invention as depicted in the drawing, showing a tool-less fastener 1 , for use in connecting a computer cable 5 to one of a computer port connection 12 and a peripheral port connection 14 . The computer cable 5 has a connection holder 4 disposed on a terminal end. Each of the computer port connection and the peripheral port connection has an elongated receiving recess 6 (as they are interchangeable for the purpose of explaining the functioning of the tool-less fastener only one identifying number has been assigned).
The tool-less fastener comprises an elongated rod 2 having a central axis, a first end 2 a , and a second end 2 b ; means for axially biasing the rod 16 which is disposed proximate to the first end; means for restricting axial movement 18 which is disposed proximate to the second end; and a resilient sleeve 7 having an interior recess 7 a therethrough that is suitably sized to accommodate the rod 2 and has a relaxed maximum outer transverse dimension that is less than the smallest transverse dimension of the elongated receiving recess. The sleeve 7 is disposed around the rod 2 between the means for axially biasing 16 and the means for restricting axial movement 18 .
The means for axially biasing is movable between a first position in which the sleeve is relaxed having a first pressure that does not substantially exceed a nominal compressive pressure applied to the sleeve by the means for axially biasing, as shown in FIGS. 3 and 7, and a second position in which a deforming compressive pressure is applied to the sleeve by the means for axially biasing, as shown in FIGS. 4 and 8. The deforming compressive pressure compresses the sleeve axially and expands at least a portion of the sleeve radially relative to the central axis of the rod to a deformed maximum outer transverse dimension that is greater than the smallest transverse dimension of the elongated receiving recess 6 .
Thus, the second end 2 b of the rod 2 with the relaxed sleeve disposed around it can be projected from the connection holder 4 of the computer cable 5 to the receiving recess 6 of one of the computer port connection 12 and the peripheral port connection 14 when the means for axially biasing 16 is disposed in the first position, as shown in FIGS. 3 and 7. The connection holder 4 of the computer cable can be releasably connected to the receiving recess 6 of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the second position, as shown in FIGS. 4 and 8.
Referring to FIG. 3, the means for biasing 16 may comprise a first contact element (shown in the drawing as the first washer 3 ) having a central aperture 3 a and a mechanism 20 that is rotatingly attached to the rod for axial movement with respect to the rod. The first contact element may further be disposed around the rod between the sleeve 7 and the rotating mechanism (while a cam mechanism 20 is show in the drawing, an available substitute could be used). An alternative would be to provide a means to rotate a threaded rod while binding the movement of the first contact element so that it moved axially relative to the rod to bias the sleeve.
In a preferred embodiment of the present invention, the means for biasing 16 comprises a first contact element having a central aperture and a cam mechanism 20 . The cam mechanism is operatively attached to the rod 2 , and the first contact element is disposed around the rod between the sleeve 7 and the cam mechanism 20 . Moreover, the first contact element may comprise a first washer 3 , i.e. a disk or ring. Preferably, the first contact element is a first cupped washer 3 b having a concave surface disposed proximate to the sleeve 7 and the concave surface of the first cupped washer is in a face to face relationship with a proximate end 7 b of the sleeve 7 . Referring to FIG. 22, the first washer may comprise a Belleville washer 3 c with a concave surface disposed proximate to the sleeve 7 .
In another preferred embodiment of the tool-less fastener of the present invention, the rod 2 is cylindrical with a circumferential groove 11 disposed proximate to the second end 2 b , as shown in FIG. 12 . The means for restricting axial movement may further comprise a second contact element (shown in the drawing as a second washer 8 ) having a central aperture 8 a . The central aperture 8 a may have a plurality of inwardly directed radial fins 22 , as shown in FIG. 11, that are flexibly moveable between a static position in which the fins 22 are inwardly directed radially and a dynamic position in which fins flex axially relative to the central axis of the rod to allow one of the first end 2 a and the second end 2 b of the rod 2 to be inserted in to the central aperture 8 a . The plurality of fins 22 are sufficiently resilient to return to the static position when the central aperture is aligned with the circumferential groove 11 of the rod 2 . In this way, the rod 2 can be inserted in to the central aperture of the second contact element axially flexing the plurality of inwardly directed radial fins 22 until the circumferential groove 11 of the rod 2 is aligned with the central aperture allowing the plurality of fins to elastically regain the static position thereby securing the second contact element axially. Preferably, the distance between opposing fins will be less than the largest transverse dimension of the second end of the rod and less than the transverse dimension of the circumferential groove. In preferred form, the second contact element comprises a second washer 8 .
In another preferred embodiment of the present invention as shown in FIG. 14, the means for restricting axial movement comprises a second contact element, in phantom, having a central aperture of predetermined radial dimension and the rod 2 is generally cylindrical with a shoulder 2 c of increased radial dimension disposed proximate to the second end 2 b . The shoulder 2 c has an outer radial dimension greater than the predetermined radial dimension of the central aperture 8 a . The second contact element can be disposed around the rod 2 between the sleeve 7 and the shoulder 2 c . Alternately, the second contact element may be made integral to the second end 2 b of the rod 2 .
In another preferred embodiment of the tool-less fastener, the means for restricting axial movement comprises a second contact element having a central aperture of predetermined radial dimension and the rod 2 has a taper extending along at least one segment 2 d of its length tapering toward the first end 2 a of the rod and disposed proximate to the second end 2 b of the rod, as shown in FIG. 13 . The at least one segment 2 d of the rod has a section 2 e with an outer radial dimension greater than the predetermined radial dimension of the central aperture 8 a for limiting the second contact element from further axial movement in the direction of the second end 2 b of the rod.
Preferably, the contact element comprises a second washer 8 which may be a second cupped washer 8 b having a concave surface disposed proximate to the sleeve 7 . Such concave surface of the second cupped washer may be in a face to face relationship with a distal end 7 c of the sleeve 7 .
Another preferred aspect of the tool-less fastener of the present invention provides that the second end 2 b of the rod 2 be rounded, as shown in FIG. 13, to facilitate insertion into the elongated recess 6 .
Referring to FIG. 15, the rod 2 is cylindrical with a first flattened end 24 and a second flattened end 26 . The first flattened end has a transverse opening 28 for receiving a camshaft 9 . The means for biasing comprises a camshaft 9 and a cam mechanism 20 , as shown in FIG. 1 . The cam mechanism is operatively connected to the camshaft, and the means for biasing and the means for restricting axial movement comprise, respectively, a first contact element and a second contact element. Referring to FIG. 16, each of the first contact element and the second contact element has a notched central aperture 30 with one maximum transverse dimension greater than a maximum transverse dimension of the flattened end of the rod. The first contact element is disposed around the rod 2 between the sleeve 7 and the cam mechanism 20 , and the second contact element is disposed around the rod between the sleeve 7 and the second flattened end 26 .
As shown in FIGS. 1, 2 , 5 - 6 , 17 - 18 , and 21 , the tool-less fastener of this important invention includes the rod having a transverse opening 28 for receiving a camshaft 9 and the means for biasing having a camshaft and a cam mechanism including a parallel set of cam wheels 10 . The cam wheels are operatively connected to the camshaft 9 which is operatively connected to the transverse opening 28 in the rod 2 .
As best shown in FIG. 18, each of the parallel set of cam wheels 10 comprises a peripheral edge 10 a having a first segment 10 b with a constant radius of curvature and a second segment 10 c of varying radii of curvature relative to the cam hole 32 . The radial dimension of the first segment 10 b is at least as great as the largest radial dimension of the second segment 10 c , and an exterior surface 10 d of suitably sized is provided to allow the cam wheels 10 to be grasped between the finger tips of a user.
Preferably, the cam mechanism includes a parallel set of cam wheels and a lever arm 34 extending from the parallel set of cam wheels 10 to facilitate rotation of the cam wheels. As best shown in FIG. 20, the lever arm 34 has a first exterior surface 34 a that is parallel to a second exterior surface 34 b . The first and second exterior surfaces are of suitable size to allow the lever arm to be grasped between the finger tips of a user.
Another preferred embodiment of the tool-less fastener includes an extensible lever arm 36 projecting from a parallel set of cam wheels 10 to facilitate rotation of the cam wheels. The extensible lever arm 36 is movable between a first position in which the arm is retracted and a second position in which the arm is fully extended, as shown in FIG. 21. A spring 38 or like device may be employed to return the extensible lever arm 36 to its retracted position. Preferably, the second position of the extensible lever arm 36 is of suitable size to allow the lever arm to readily actuated.
The tool-less fastener operates by the introduction of radial forces, shown by radiating arrows in FIGS. 4, 8 , and 9 , exerted by the deformed sleeve upon the recesses into which it is disposed to effectuate restricting axial movement. Preferably, the elongated recess has an interior surface comprising one of a rough surface and a smooth surface. Such rough surface may be threaded, as shown in FIG. 2 for example, or knurled. Moreover, the sleeve may have a textured exterior surface.
As shown in FIGS. 1, 3 , 5 , 7 , and 9 of the drawing, the relaxed sleeve has a cylindrical outer shape and the elongated receiving recess has a generally cylindrical shape.
Referring to FIGS. 1 and 5, the connection holder 4 comprises a flange.
Preferably, the materials of construction should be non-conductive. A polycarbonate material is suitable for the elongated rod and cam mechanism. Buna-N (or Vitol made by Dow Chemical) may be used for the resilient sleeve. Suitable substitutes will be apparent to those skilled in the art.
In a second preferred embodiment of the present invention, as shown in FIGS. 1-4, the tool-less fastener is independent of the computer cable. The connection holder 4 of the computer cable 5 has a hole 40 for receiving the resilient sleeve 7 , as best shown in FIG. 1 . Additionally, the relaxed maximum outer transverse dimension of the resilient sleeve is less than the smallest transverse dimension of the hole 40 , and the deformed maximum outer transverse dimension is greater than the smallest transverse dimension of the hole 40 . The rod with the relaxed sleeve disposed around it can be introduced to the hole 40 of the connection holder of the computer cable and the receiving recess of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the first position, and the connection holder of the computer cable can be releasably connected to the receiving recess of one of the computer port connection and the peripheral port connection by the radial forces of the deformed sleeve when the means for axially biasing is disposed in the second position.
Preferably, the smallest transverse dimension of the hole 40 corresponds generally to the smallest transverse dimension of the elongated receiving recess 6 .
In a preferred embodiment of the present invention, a tool-less fastener, for use in connecting a computer cable to one of a computer port connection and a peripheral port connection is taught. The computer cable 5 has a connection holder 4 disposed on a terminal end thereof, and each of the computer port connection and the peripheral port connection has an elongated receiving recess 6 . The fastener comprises the following elements: an elongated rod 2 having a central axis, a first end 2 a , a second end 2 b , and a transverse opening 28 proximate to the first end 2 a ; means for axially biasing 16 the rod 2 which is disposed proximate to the first end 2 a , where the means for biasing includes a camshaft 9 and a cam mechanism 20 including a parallel set of cam wheels 10 that are operatively connected to the camshaft 9 , with the camshaft being operatively connected to the transverse opening 28 in the rod 2 , and attached thereto; and a first cupped washer 3 b having a central aperture 3 a and a concave surface disposed proximate to the sleeve 7 , said first cupped washer is disposed around the rod between the sleeve and the cam mechanism; means for restricting axial movement 18 which is disposed proximate to the second end 2 b ; and a resilient sleeve 7 having an interior recess 7 a therethrough that is suitably sized to accommodate the rod and having a relaxed maximum outer transverse dimension that is less than the smallest transverse dimension of the elongated receiving recess 6 .
The sleeve 7 is disposed around the rod 2 between the means for axially biasing and the means for restricting axial movement. The means for axially biasing is movable between a first position in which the sleeve is relaxed having a first pressure that does not substantially exceed a nominal compressive pressure applied to the sleeve by the means for axially biasing and a second position in which a deforming compressive pressure is applied to the sleeve by the means for axially biasing.
The deforming compressive pressure compresses the sleeve axially and expands at least a portion of the sleeve 7 radially relative to the central axis of the rod 2 to a deformed maximum outer transverse dimension that is greater than the smallest transverse dimension of the elongated receiving recess 6 . Thus, the second end 2 b of the rod with the relaxed sleeve disposed around it can be projected from the connection holder 4 of the computer cable to the receiving recess 6 of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the first position, and the connection holder 4 of the computer cable can be releasably connected to the receiving recess 6 of one of the computer port connection 12 and the peripheral port connection 14 when the means for axially biasing is disposed in the second position.
In another preferred embodiment of the tool-less fastener of the present invention, the fastener extends from a computer cable 5 , for use in connecting the computer cable to one of a computer port connection and a peripheral port connection. The computer cable has a connection holder 4 disposed on a terminal end thereof, and each of the computer port connection and the peripheral port connection having an elongated receiving recess 6 . The fastener further comprises an elongated rod 2 having a central axis, a first end, a second end, and a transverse opening 28 proximate to the first end 2 a ; the connection holder 4 of the computer cable 5 has a hole 40 for receiving a resilient sleeve 7 ; means for axially biasing the rod which is disposed proximate to the first end 2 a including a camshaft 9 and a cam mechanism 20 including a parallel set of cam wheels 10 , where the cam wheels are operatively connected to the camshaft, and the camshaft is operatively connected to the transverse opening in the rod, and attached to the rod, and a first cupped washer 3 b having a central aperture 3 a and a concave surface disposed proximate to the sleeve 7 is provided. The first cupped washer 3 b is disposed around the rod between the sleeve 7 and the cam mechanism 20 . Means for restricting axial movement which is disposed proximate to the second end 2 b , and a resilient sleeve 7 having an interior recess 7 a therethrough that is suitably sized to accommodate the rod 2 and having a relaxed maximum outer transverse dimension that is less than the smallest transverse dimension of the elongated receiving recess 6 are further provided.
The sleeve 7 is disposed around the rod 2 between the means for axially biasing and the means for restricting axial movement. The means for axially biasing is movable between a first position in which the sleeve is relaxed having a first pressure that does not substantially exceed a nominal compressive pressure applied to the sleeve by the means for axially biasing and a second position in which a deforming compressive pressure is applied to the sleeve by the means for axially biasing.
The relaxed maximum outer transverse dimension of the resilient sleeve 7 is less than the smallest transverse dimension of the hole 40 . The deforming compressive pressure compresses the sleeve axially and expands at least a portion of the sleeve radially relative to the central axis of the rod to a deformed maximum outer transverse dimension that is greater than the smallest transverse dimension of the elongated receiving recess 6 , and the deformed maximum outer transverse dimension is greater than the smallest transverse dimension of the hole 40 .
Accordingly, the second end 2 b of the rod 2 with the relaxed sleeve is disposed around it can be projected from the connection holder 4 of the computer cable 5 to the receiving recess 6 of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the first position, and the connection holder 4 of the computer cable can be releasably connected to the receiving recess 6 of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the second position. The rod with the relaxed sleeve disposed around it can be introduced to the hole of the connection holder of the computer cable and the receiving recess of one of the computer port connection and the peripheral port connection when the means for axially biasing is disposed in the first position, and the connection holder of the computer cable can be releasably connected to the receiving recess of one of the computer port connection and the peripheral port connection by the radial forces of the deformed sleeve when the means for axially biasing is disposed in the second position.
Preferably, the means for restricting axial movement comprises a second contact element having a central aperture 8 a . The central aperture has a plurality of inwardly directed radial fins 22 with the distance between opposing fins being less than the largest transverse dimension of the second end 2 b of the rod and less that the transverse dimension of the circumferential groove 11 . The plurality of fins is flexibly moveable between a static position in which the fins are inwardly directed radially and an dynamic position in which fins flex axially relative to the central axis of the rod to allow one of the first end and the second end of the rod to be inserted in to the central aperture, and the plurality of fins 22 is sufficiently resilient to return to the static position when the central aperture 8 a is aligned with the circumferential groove 11 of the rod 2 , hence, the rod can be inserted in to the central aperture 8 a of the second contact element axially flexing the plurality of inwardly directed radial fins 22 until the circumferential groove of the rod is aligned with the central aperture allowing the plurality of fins to elastically regain the static position thereby securing the second contact element axially. Moreover, the second end 2 b of the rod may be rounded, as shown in FIG. 13, to facilitate insertion into the elongated recess 6 .
While this invention has been described in connection with the best mode presently contemplated by the inventor for carrying out his invention, the preferred embodiments described and shown are for purposes of illustration only, and are not to be construed as constituting any limitations of the invention. Modifications will be obvious to those skilled in the art, and all modifications that do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.
The invention resides not in any one of these features per se, but rather in the particular combination of all of them herein disclosed and claimed and it is distinguished from the prior art in this particular combination of all of its structures for the function specified. It will be apparent to one skilled in the art that the fastener of the present invention is applicable to may types of connection, including, without limitation, audio (sonic), data transfer via cable for serial port, parallel port, and related connections, and fiber optics. For any connection where previously a typical attachment would have been made by a screw and threaded hole, the fastener of the present invention could now be employed. This fastener will work, without any modification being fastener into an existing cable holder in place of the original screw and then inserting it into the original threaded hole, a secure connection can be made.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A tool-less fastener for use in connecting a computer cable to either a computer or peripheral equipment. An elongated rod with an external expandable sleeve fits into a standard threaded hole and then expanded to fasten the cable to the equipment without the need for a screwdriver or other tool. The tool-less fastener may be independent of or interconnected to the computer cable. | 5 |
TECHNICAL FIELD
This invention relates to accessing long distance network carriers and, in particular, to the selection of such long distance network carriers.
BACKGROUND OF THE INVENTION
Within the United States, there are a number of network access providers (also referred to as long distance carriers or network carriers). For the consumer market, each of these carriers offer different long distance service plans. In addition, these plans vary often weekly or monthly as each of the carriers tries to gain a greater market share of the consumer long distance market. Often the proposed service plans are tailored to fit only certain call habits of consumers. In addition, the introduction of a new plan often provides service at a lower price for some fixed period of time, for example a month. Not only do these service plans change on a continuous basis, but these service plans require careful reading and the use of these service plans requires careful attention to when calls are made in order to reduce the monthly charge under a particular service plan.
It is known in the prior art to have devices that monitor the amount of time spent on a given call and to estimate the cost of that call based on simple parameters. The problems that exist however for the average consumer is choosing service plans on an ongoing basis and determining when to place calls to obtain the maximum economic advantage under the chosen service plan.
SUMMARY OF THE INVENTION
The proceeding problems are solved and a technical advance is achieved by an apparatus and method that allows a separate system owned by a service provider to access telephone terminals of consumers to determine the calling patterns of each consumer, utilize service plan information of different network carriers, automatically change the network carriers used by an individual consumer to more closely match the calling patterns of the consumer and the plan incentives, and to store information in the telephone terminal so that calling information is provided to the individual consumer in accordance with the service plan of the selected network carrier. Advantageously, the information stored in the telephone terminal of the consumer causes that telephone terminal to alert the consumer to special times during which the consumer should make telephone calls. In addition, the telephone terminal will warn the consumer upon the consumer attempting to place a call if there is a more advantageous time to place the call within some predefined time period.
These and other features and advantages of the invention will become more apparent from the following description of an illustrative embodiment of the invention considered together with the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 illustrates a telecommunication system embodying the invention;
FIG. 2 illustrates a pictorial illustration of a telephone terminal;
FIG. 3 illustrates in greater detail a block diagram of a telephone terminal;
FIGS. 4-6 illustrate, in flow chart form, the steps performed by a computer of a telephone terminal; and
FIGS. 7-9 illustrates, in flow chart form, the steps performed by a service provider system.
DETAILED DESCRIPTION
FIG. 1 illustrates a telecommunication system having central office 101 that interconnects telephone terminals 102 through 103 to each other and also to distant central offices via network carriers 104-105. Within the prior art, the user of each of the telephone terminals would have to individually contact one of the network carriers and request that the selected network carrier provide long distance network service for the user. The network carrier would then administratively inform the Regional Bell Operating Company (RBOC) controlling central office 101 of the user's choice, and central office 101 would store information specifying which long distance carrier the user had chosen. In addition to telephone terminals 102-103, ordinary telephones 106-107 are also interconnected to central office 101.
Service provider 108 provides a special service to telephone terminals 102-103. Telephone terminals 102-103 each have a computer which monitors and records the time and duration of telephone calls made. Service provider system 108 periodically transfers this stored information to itself. Based on service plan information that is received from network carriers 104-105, service provider system 108 determines if thenetwork carrier for each of telephone terminals 102-103 should be modified. If service provider system 108 determines that a network carrier for a particular telephone terminal should be modified, service provider system 108 contacts the new network carrier and requests that the new network carrier inform the RBOC that it is to be the new carrier so that the RBOC can modify the information stored in central office 101 which determines the network carrier for the particular telephone terminal. After the change has been made designating the new network carrier as the network carrier for a particular telephone terminal, service provider system 108 transfers information defining the new service plan to the telephone terminal so that the telephone terminal can guide the user in the utilization of the new service plan.
Utilizing the service plan information received from service provider system 108, the telephone terminal alerts the user to less expensive days for making long distance telephone calls at a predefined period before such a day occurs by flashing a message on the telephone terminal that can be read by the user. Advantageously, this predefined period is 24 hours. In addition, when the user attempts to place a telephone call during an expensive period, the telephone terminal displays a message advising the user of a time period that would be less expensive. During the course of a telephone call, telephone terminal calculates on an ongoing basis the cost of the telephone call and display this cost to the user. In addition, the telephone terminal maintains the total cost of long distance calls during a billing period. The user can access this billing information and have it displayed on the telephone terminal. Advantageously, when a new service plan has been selected and installed, the telephone terminal alerts the user to this fact, and the user can directly interrogate the telephone terminal to determine the cost of placing long distance telephone calls for various periods of time. In addition, when a user starts to dial a long distance call, the telephone terminal prompts the user for the expected duration of that call. Based on the service plan and the expected length of the call, the telephone terminal advises the user to call at a different time or the telephone terminal chooses a different network carrier. A different network carrier is selected by preceding the long distance call with a interexchange carrier code to select another carrier other than the one currently designated in the central office to serve this particular telephone terminal.
FIG. 2 shows a pictorial view of telephone terminal 102. The other telephone terminals are identical in design. FIG. 3 shows a block diagram of telephone terminal 102. As can be seen in FIG. 2, alphanumeric display 202 is utilized to display textual messages to the user of the terminal. Alphanumeric display 202 is utilized to alert and explain to the user a new service plan and also to inform the user of alternate times for placing long distance calls. Keyboard 201 is utilized by the user to enter more information as requested by computer 301 of FIG. 3. Keypad 204 is configured as a normal telephone dialing keypad. Function buttons 203 are a series of buttons that allow the user to automatically select such functions as call last telephone number, abbreviating dialing, etc.
FIG. 3 illustrates a block diagram of telephone terminal 102. Link 109 is assumed for the sake of simplicity to be a BRI ISDN link. One skilled in the art, could readily envision that a analog telephone link could be utilized with a modem to receive and transmit digital data. ISDN interface 302 is responsive to data on link 109 to transfer both control messages, data messages, and voice to computer 301. Computer 301 is responsive to encoded voice from ISDN interface 302 to transmit this information to handset 206 via converter 303 which is both a digital to analog converter and an analog to digital converter. Analog voice information received from handset 206 by converter 303 is digitized and transferred through computer 301 to ISDN interface 302. Computer 302 utilizes memory 304 to store both data and program instructions. Elements 201-202 are interfaced to computer 301 utilizing well known techniques. Computer 301 includes a real time clock.
Computer 301 is responsive to the generation of calls via function buttons 203, keyboard 201, or keypad 204 to transmit the proper ISDN setup messages via link 109. In addition, computer 301 monitors for long distance calls being generated and will request the estimated duration of the long distance calls in order to determine the least cost using the current service plan or choosing an alternate network carrier if the alternate network carrier is cheaper.
FIGS. 4-6 illustrate the steps performed by computer 301 of telephone terminal 102 in implementing the invention. Decision block 401 determines if a new service plan has been downloaded from service provider system 108 via link 109. If the answer is no, decision block 402 determines if a non-long distance call operation is being requested by the user of telephone terminal 102. Such an operation would be a local telephone call, administering one of the function buttons, etc. If the answer is yes in decision block 402, control is processed to block 403 which performs normal processing of the request before returning control back to decision block 401.
If the answer is no in decision block 402, decision block 404 determines if the user is attempting to place a long distance call. If the answer is yes, block 406 displays a message on alphanumeric display 202 requesting that the user enter an estimated duration of the call. Block 406 then receives the user's response designating the estimated call duration. Block 407 calculates using the present time of day and the estimated call duration the cost of placing such a call utilizing the present service plan of the designated network carrier. Next, block 408 adds a predefined time interval to the present time of day and utilizing the resulting time and the estimated call duration calculates a second cost based on the service plan. The predefined time interval is the maximum time that the user will be asked to wait if a cheaper rate can be obtained under the service plan by waiting a time less than or equal to this predefined time interval. After execution of block 408, block 409 uses the present time of day and the estimated call duration and calculates a set of costs for each of the other network carriers available through central office 101. This is done to determine if a non-designated carrier has a cheaper rate than the designated carrier. After execution of block 409, control is transferred to decision block 501 of FIG. 5.
Decision block 501 compares the first calculated cost with the second calculated cost. If the first cost is less than or equal to the second cost, control is transferred to decision block 502 which compares the first calculated cost with each of the costs determined for the other network carriers. If the first calculated cost is less than or equal to any of these costs, a call setup operation is performed by execution of block 503 by computer 301 utilizing ISDN interface 302 to set up the call via central office system 101 using the selected carrier. After execution of block 503, control is transferred to decision block 401 of FIG. 4. If the result of decision block 502 is no, the call is set up using the other network carrier having the lowest cost by execution of block 504. After execution of block 504, control is transferred to decision block 401 of FIG. 4.
Returning to decision block 501, if the second calculated cost is less than the first calculated cost indicating that money could be saved by waiting the predefined time, control is transferred to block 506 which determines if the second calculated cost is less than each of the set of costs calculated for the other network carriers. If the answer is no, control is transferred to block 504 whose operation has been previously described. If the answer is yes in decision block 506, control is transferred to block 507 which displays a message asking is the user wants to wait the predefined amount of time before proceeding with the call. Decision block 508 waits for the user's response. If the user wishes to wait, block 509 sets up the call with the selected carrier after waiting the predefined amount of time before transferring control back to decision block 401 of FIG. 4. If the user does not wish to wait, block 511 sets up the call with the selected carrier before transferring control back to decision block 401 of FIG. 4. At this point, the user could always take the information into account and then abandon the call. If this occurs, block 511 will transfer control back to decision block 401 of FIG. 4 without setting up the call with the selected carrier.
Returning to decision block 401 of FIG. 4, if a new service plan has been received from service provider system 108, control is transferred to block 411. The later block displays a message on alphanumeric display 202 indicating that a new service plan is in effect. The message also informs the user of the operations that the user needs to perform with keyboard 201 to obtain these new instructions. After execution of block 411, control is transferred back to decision block 401.
Returning to decision block 404, if the answer is no indicating that no type of call operation is being performed, control is transferred to decision block 612 of FIG. 6. Decision block 612 determines if the user is requesting service plan information. The user may request this information either because of the message that was displayed by block 411 or merely because the user wishes to refresh their memory concerning the service plan. If the answer is yes in decision block 612, block 613 displays the service plan to the user. Block 613 provides the user the capability of searching through the service plan using well known search tools. After execution of block 613, control is transferred back to decision block 401 of FIG. 4. If the answer is no in decision block 612, decision block 614 determines if there is an active long distance call. If the answer is no, block 616 performs normal processing before returning control back to decision block 401 of FIG. 4. If the answer in decision block 614 is yes, block 617 determines the cost of the current call and displays this cost on alphanumeric display 202 to the user before transferring control to block 618. The latter block updates the total long distance cost for the present month before transferring control to block 619. The latter block then updates the long distance database with information defining when the call was originally originated and its duration and the network carrier utilized. In addition, the total time of the call is also inserted into the database as well as when the user wished to place the call.
FIGS. 7-9 illustrate the steps performed by service provider system 108 in implementing the invention. Decision block 701 determines if it is time to review the service plans of the other network carriers in comparison to each telephone terminal's present service plan and the calling patterns of each telephone terminal. If the answer is no in decision block 701, decision block 702 determines if a new service plan has been received from any of the network carriers. One skilled in the art could readily recognize that this information could be received in paper form and entered manually into system provider system 108 or could be received via a data link from the network carriers. If the answer in decision block 702 is no, block 705 performs normal processing before returning control back to decision block 701. If the answer in decision block 702 is yes, block 703 sets the next terminal variable that is utilized by blocks 704-712 of FIG. 7 and blocks 801-803 of FIG. 8 equal to the first telephone terminal in the list of telephone terminals maintained by service provider system 108. Decision block 704 then determines if there is another telephone terminal in the list that has not yet been processed. Since the answer is yes for the first telephone terminal, control is transferred to block 706 which accesses the long distance database of the telephone terminal via central office system 101 and the appropriate link to the telephone terminal. Block 707 then accesses the present service plan of the telephone terminal, and block 708 calculates the average monthly cost (referred to as the new cost) over the last two months based on the new service plan and the data received from the database of the telephone terminal. Block 709 calculates the actual cost incurred by the telephone terminal for the last two months utilizing the data in the access database. Decision block 711 then determines if the actual cost is less than the new cost calculated in block 708. If the answer is yes, block 712 selects the next terminal in the list maintained by service provider system 108 and transfers control back to decision block 704.
If the answer in decision block 711 is no indicating that the actual cost is greater than the cost calculated under a new service plan, control is transferred to block 801 of FIG. 8 which sends a message to the RBOC controlling central office system 101 designating that the network carrier associated with the new service plan is to be the designated network carrier for the telephone terminal. One skilled in the art could readily see, that this information could be conveyed to the RBOC controlling central office system 101 either as verbal information, textual information, or as digital data via a data link. After execution of block 801, control is transferred to decision block 802. The latter decision block waits until a message is received from the RBOC controlling central office system 101 either digitally or via the interaction of a human before transferring control to block 803. Block 803 then transmits the new service plan to the telephone terminal and transfers control to block 804. The latter block selects the next terminal in the list maintained by service provider system 108 as the next terminal and transfers control back to decision block 704 of FIG. 7.
Returning to decision block 701 of FIG. 7, if decision block 701 indicates that it is time to review the service plans of the various network carriers, control is transferred to block 903 of FIG. 9. Block 903 sets the next terminal variable to the first terminal of the list maintained by service provider system 108 and transfers control to decision block 904. Decision block 904 determines if there is another terminal in the list to be processed. In the case of the first terminal on the list, the answer is yes, and control is transferred to block 906. If the answer is no in decision block 904, control is transferred back to decision block 701 of FIG. 7. Block 906 accesses the long distance database of the next telephone terminal, and block 907 accesses the present service plan of the next telephone terminal. Block 908 uses all of the other available service plans from the other network carriers and the database of the next terminal to calculate a set of average monthly costs for the last two months using these other service plans. Block 909 calculates the average monthly actual cost for the last two months of the telephone terminal utilizing the information in the database. Decision block 911 determines if the actual cost is greater than any of the costs of the other service plans. If the answer is no, block 912 selects the next terminal on the list and transfers control back to decision block 904. If the answer in decision block 911 is yes, block 913 designates to the RBOC controlling central office system 101 that the other network carrier with the lowest cost be used and transfers control to decision block 914. The latter decision block waits for a confirmation message that the new carrier is in use for the terminal before transferring control to block 916. Block 916 transmits the new service plan to the telephone terminal, and block 917 selects the next terminal from the list to be processed and transfers control back to decision block 904.
It is to be understood that the above-described embodiment is merely illustrative of the principles of the invention and that other arrangements may be devised by those skilled in the art without departing from the spirit or scope of the invention. | Allowing a separate system owned by a service provider to access telephone terminals of consumers to determine the calling patterns of each consumer, utilize service plan information of different network carriers, automatically change the network carriers used by an individual consumer to more closely match the calling patterns of the consumer and the plan incentives, and to store information in the telephone terminal so that calling information is provided to the individual consumer in accordance with the service plan of the selected network carrier. The information stored in the telephone terminal of the consumer causes that telephone terminal to alert the consumer to special times during which the consumer should make telephone calls. In addition, the telephone terminal will warn the consumer upon the consumer attempting to place a call if there is a more advantageous time to place the call within some predefined time period. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the US National Stage of International Application No. PCT/EP2005/051171, filed Mar. 15, 2005 and claims the benefit thereof. The International Application claims the benefits of German Patent application No. 10 2004 012 756.5 filed Mar. 15, 2004. All of the applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
The invention relates to a method and device for controlling an internal combustion engine.
BACKGROUND OF THE INVENTION
The requirements relating to the output and efficiency of internal combustion engines are become increasingly stringent. At the same time strict legal provisions require emissions to be kept at low levels. Such requirements can be easily satisfied, if the internal combustion engine is fitted with gas exchange valves and corresponding drives for these, with different valve lift characteristics as a function of the working point of the internal combustion engine. This allows throttle losses to be reduced as air is taken in and optionally allows high exhaust gas recirculation rates to be rapidly set.
It is known that the valve lift of a gas inlet valve in the internal combustion engine can be adjusted between a low and high valve lift. For example the Porsche 911 Turbo is fitted with a device for adjusting the valve lift of the gas inlet valve and the gas outlet valve. The internal combustion engine of the said vehicle is also provided with a camshaft, on which a cam with a low lift and two further cams with a higher lift are configured for each gas inlet valve. The cam lift is transmitted to the gas inlet valve by means of a transformer unit. The transformer unit is configured as a bucket tappet, comprising a cylinder element and an annular cylinder element disposed concentrically in relation to it. The cam with a low lift acts on the cylinder element, while the cams with the higher lift act on the annular cylinder element. As a function of the position of the bucket tappet, either the low or higher lift is transmitted to the gas inlet valve. During no-load operation of the internal combustion engine, the low cam lift is transmitted to the gas inlet valve. This results in reduced frictional losses due to the small diameter of the cam used in this operating state and the cylinder element and the lower valve lift.
A higher charge movement is also achieved. This enables the emissions of the internal combustion engine to be reduced and fuel consumption to be kept low at the same time. The low valve lift is maintained at low and medium load. If the load requirements imposed on the internal combustion engine are high, a switch is made to the higher valve lift.
If an intended switch of the valve lift actually fails to take place and this is not identified, it results in an increase in pollutant emissions in the respective cylinder during the combustion process.
SUMMARY OF THE INVENTION
The object of the invention is to create a method and device for controlling an internal combustion engine, which enable low levels of pollutant emissions to be achieved during operation of the internal combustion engine.
The object is achieved by the features of the independent claims. Advantageous embodiments of the invention are characterized in the subclaims.
According to a first aspect, the invention is characterized by a device for controlling an internal combustion engine, with an intake pipe, which leads to an inlet of a cylinder, on which a gas inlet valve is disposed. A valve drive for the gas inlet valve is also assigned to the internal combustion engine, by means of which the valve lift of the gas inlet valve can be adjusted by means of an actuator element, by means of which different cams can be made to act on the gas inlet valve. An inductive actuator drive acts on the actuator element, a voltage being induced in said inductive actuator drive during the course of a switching process. The device comprises a first unit, which is configured to identify whether switching of the valve lift has taken place based on the induced voltage in the inductive actuator drive, which is characteristic of the switching process. It also comprises a second unit, which is configured to control at least one further actuator body, as a function of whether switching has been identified in the first unit.
According to a further aspect, the invention is characterized by a method for controlling the internal combustion engine, wherein switching of the valve lift is identified based on the induced voltage in the inductive actuator drive, which is characteristic of the switching process, and wherein at least one actuator body is activated as a function of whether switching has been identified.
The invention therefore utilizes the knowledge that during the course of a switching process the voltage, which is characteristic of the switching process, is induced in the inductive actuator drive. According to the invention, in addition to its own actual function as a drive unit, the inductive actuator drive is also used as a sensor, thus allowing simple identification of whether a switching process has actually taken place. This identification also takes place so close in time to the actual occurrence or otherwise of the switching process that at least one actuator body can quickly be accessed, for example an injection valve or a spark plug, even before the power lift of the respective cylinder, which directly follows the required switching of the valve lift.
According to one advantageous embodiment of the invention, the first unit is configured to verify whether the induced voltage characteristic of the switching process occurs in the inductive actuator drive within a predetermined camshaft angle range.
This has the advantage that the verification of whether the characteristic induced voltage occurs only has to take place within a predetermined time window, corresponding to the predetermined camshaft angle range, and less computing outlay is therefore required. It is also possible to identify even more precisely whether the required switching process of the valve lift has actually taken place, as voltage fluctuations that may occur outside the predetermined camshaft angle range cannot be identified erroneously as the characteristic induced voltage.
According to a further advantageous embodiment of the invention, the first unit has a measuring unit, which is configured to measure a voltage drop over the inductive actuator drive in relation to a supply potential of the inductive actuator drive. This has the advantage that fluctuations in the supply potential do not influence the quality of measurement of the voltage drop. This is an important advantage with regard to controlling an internal combustion engine, as the supply potential of a voltage supply for a motor vehicle, in which the internal combustion engine can be disposed, is regularly subject to major fluctuations and the characteristic induced voltage in some instances only has a small potential difference of for example 0.7 V.
According to a further advantageous embodiment of the invention, the first unit has a conversion unit, which is configured to convert the voltage drop over the inductive actuator drive, as detected by the measuring unit, to a corresponding voltage drop in relation to a reference potential, which can also be referred to as ground potential, of an evaluation unit. This allows simple evaluation of the voltage drop detected by the measuring unit in the evaluation unit. This is particularly advantageous, when the evaluation unit is configured as a microcontroller, the inputs of which are generally related to the reference potential.
According to a further advantageous embodiment of the invention, the measuring unit is assigned a resistor, which can be connected by means of a switch parallel to the inductive actuator drive. This means that the voltage drop at the inductive actuator drive can be measured in a particularly simple manner.
According to a further advantageous embodiment of the invention, the measuring unit is configured to detect the voltage drop over a number of inductive actuator drives. This has the advantage that the voltage drop over a number of inductive actuator drives can thus be detected in a more economical manner and no multiplexer is required.
According to a further advantageous embodiment of the invention, the measuring unit has a buffer for the detected voltage drop. This has the advantage, particularly in respect of a characteristic induced voltage that only occurs for a very short time, that correspondingly detected measured values can also be read into the evaluation unit at a different time.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are described in more detail below with reference to the schematic drawings, in which:
FIG. 1 shows an internal combustion engine with a controller,
FIG. 2 shows a further view of parts of the internal combustion engine according to
FIG. 1 ,
FIGS. 3 a and 3 b show characteristics of a groove of an actuator element plotted over the crankshaft angle,
FIG. 4 shows a block circuit diagram of parts of the controller,
FIG. 5 shows a flow diagram of a program, operating in an evaluation unit,
FIG. 6 shows a flow diagram of a program operating in a second unit and
FIG. 7 shows a second block circuit diagram of parts of the controller.
Elements with the same structure or function are marked with the same reference characters in all the figures.
DETAILED DESCRIPTION OF THE INVENTION
An internal combustion engine ( FIG. 1 ) has an intake tract 1 , an engine block 2 , a cylinder head 3 and an exhaust gas tract 4 . The intake tract 1 preferably has a throttle valve 5 , a manifold 6 and an intake pipe 7 , which leads to a cylinder Z 1 via an inlet duct into the engine block 2 .
The engine block 2 also has a crankshaft 9 , which is coupled via a connecting rod 10 to a piston 12 of the cylinder Z 1 .
The cylinder head 3 has a valve drive with a gas inlet valve 13 and a gas outlet valve 14 and valve drives 15 , 16 assigned to these. The valve drives 15 , 16 comprise a camshaft 18 , which is coupled by means of a coupling mechanism 19 to the crankshaft 9 . The phase angle between the crankshaft 9 and the camshaft 18 can be specified beforehand. It can however also be adjustable.
An actuator element 20 is coupled mechanically to the camshaft 18 . The actuator element 20 preferably comprises a first cam 21 and a second cam 22 . The first and second cams 21 , 22 have different cam lifts. They can however also generally have different cam characteristics.
An inductive actuator drive 23 can be made to act on the actuator element 20 and thus brings about an adjustment of the actuator element 20 in the axis marked X. The inductive actuator drive has a pin 24 , which can be moved in the direction of the actuator element 20 by corresponding energizing of the inductive actuator drive 23 in the axis marked Y. The actuator element 20 has a groove 25 , into which the pin 24 can be inserted. If the pin 24 is located in the groove 25 during rotation of the camshaft 18 , the actuator element 20 is displaced in an axial direction in relation to the camshaft 18 , i.e. in the direction of the axis marked X.
The characteristics of the groove 25 in the direction marked X are shown in relation to the crankshaft angle CRK with reference to FIG. 3 a . The characteristics of the groove in a radial direction r are shown in relation to the axis marked Y with respect to the crankshaft angle CRK with reference to FIG. 3 b . The groove only extends in a radial direction r over a sub-area of the periphery of the actuator element 20 . The basic circle of the actuator element 20 is thereby marked r 0 . The groove 25 is thus not configured in a first crankshaft angle range CRK 1 . Its depth decreases in a radial direction in a crankshaft angle range CRK 2 until the groove is finally no longer present. In a third crankshaft angle range CRK 3 the groove 25 has a constant position in the direction marked by the axis X. In a fourth crankshaft angle range CRK 4 the groove has a changing position in relation to the axis X. In the fourth crankshaft angle range CRK a pin 24 engaged in the groove 25 causes a corresponding axial displacement of the actuator element 20 in the direction of the axis X.
The cylinder head 3 also has an injection valve 28 and a spark plug 29 .
A controller 30 is also provided, to which sensors are assigned, which detect different measured variables and respectively determine the measured value of the measured variable. The controller, which can also be referred to as a device for controlling the internal combustion engine, determines manipulated variables as a function of at least one measured variable, said manipulated variables then being converted to one or more control signals to control actuator bodies.
The sensors are a pedal position sensor 38 , which detects the position of an accelerator pedal 39 , an air mass sensor 32 , which detects an air mass flow, a temperature sensor 33 , which detects an intake air temperature, an intake pipe pressure sensor 34 , which detects the intake pipe pressure, a crankshaft angle sensor 35 , which detects a crankshaft angle CRK, to which a speed N is then assigned, a camshaft angle sensor 37 , which detects a camshaft angle NW. Any sub-set of the said sensors or even additional sensors can be present, depending on the embodiment of the invention.
The actuator bodies are for example the throttle valve 5 the gas inlet and gas outlet valves 13 , 14 , the injection valve 28 , the spark plug 29 or even the actuator element 20 .
As well as the cylinder Z 1 , the internal combustion engine preferably also has further cylinders Z 2 , Z 3 , Z 4 , to which corresponding sensors and actuator bodies are assigned and which are activated correspondingly.
The controller 30 is preferably one assembly unit. It can however also be made up of individual assembly units that are physically separate from each other. The controller 30 comprises a first unit 40 , which is configured to identify whether switching of the valve lift VL has taken place based on an induced voltage at the inductive actuator drive 23 , which is characteristic of the switching process. The controller 30 also comprises a second unit 41 , which is configured to activate at least one actuator body, for example the injection valve 28 and/or the spark plug 29 , as a function of whether switching of the valve lift VL has been identified in the first unit 40 .
The first unit 40 comprises a measuring unit 42 , which is configured to measure a voltage drop V over the inductive actuator drive 23 in relation to a supply potential VBAT ( FIG. 4 ) of a voltage supply, preferably an on-board voltage supply system in a motor vehicle. The inductive actuator drive 23 is coupled on the one hand to the supply potential VBAT. On the other hand the inductive actuator drive 23 can be coupled in an electrically conductive manner to the reference potential GND, as a function of the position of a first switch SW 1 and the inductive actuator drive 23 is similarly coupled in an electrically conductive manner to a Zener diode D 1 . A second switch SW 2 is also provided, as a function of whose position the measuring unit 42 can be connected parallel to the inductive actuator drive 23 .
To measure the voltage drop V over the inductive actuator drive 23 , the first switch SW 1 is controlled into its open position and the second switch SW 2 is controlled into its closed position. The measuring unit 42 then detects the voltage drop V over the inductive actuator drive 23 and generates a corresponding measurement signal VM at its output, via which it is coupled in an electrically conductive manner to a conversion unit 44 . The measuring unit 42 thus detects the voltage drop V over the inductive actuator drive 23 in relation to the supply potential VBAT.
The conversion unit 44 converts the measurement signal VM of the measuring unit 42 into an output signal VE, which is related to the reference potential GND. This can be done for example by means of a current balancing circuit. At the same time the measurement signal VM of the measuring unit 42 is preferably amplified in the conversion unit 44 . The output signal VE of the conversion unit 44 is then an input signal for the evaluation unit 46 . The output signal VE of the conversion unit 44 is preferably fed to an analog/digital converter input of the evaluation unit 46 and converted there from analog to digital.
The correspondingly digitized output signal VE of the conversion unit 44 is then further processed in the evaluation unit 46 and then optionally rescaled there into the voltage drop V over the inductive actuator drive 43 . During operation of the internal combustion engine a program is run in the evaluation unit 46 , said program being described in more detail below with reference to the flow diagram in FIG. 5 .
The program is started in a step S 1 , in which variables can optionally be initialized. The start of the program preferably takes place close in time to the starting up of the internal combustion engine. In a step S 2 it is verified whether there is a requirement to switch the valve lift VL from a low valve lift LO to a high valve lift HI or vice-versa. The actual switching process is controlled by a function in the controller 30 , which activates the inductive actuator drive 23 during the first crankshaft angle range CRK 1 by corresponding activation of the switch SW 1 , such that the pin 24 moves into the groove 25 . If the condition of step S 2 is not satisfied, processing continues in a step S 4 , in which the program is halted for a predetermined waiting period T_W, before the condition of step S 2 is verified again.
If however the condition of step S 2 is satisfied, it is verified in a step S 6 whether the current camshaft angle NW is greater than a first camshaft angle NW 1 and at the same time smaller than a second camshaft angle NW 2 . Alternatively the presence of a corresponding crankshaft angle CRK can be verified here, taking the current phase angle between the crankshaft 9 and the camshaft 18 into account correspondingly. The first and second camshaft angles NW 1 , NW 2 are selected such that the camshaft angle range in between corresponds roughly to the second crankshaft angle range CRK 2 , in which the depth of the groove 25 decreases to zero.
If the condition of step S 6 is not satisfied, processing continues in step S 4 . If however the condition of step S 6 is satisfied, in a step S 8 the current voltage drop V over the inductive actuator drive 23 is read in. This can be done for example by controlling the switch SW 2 into its closed position at this time and at the same time ensuring that the switch SW 1 is in its open position. The measuring unit 42 then generates its measurement signal VM, which in turn is converted in the conversion unit 44 into the output signal VE and then in turn read in in the evaluation unit 46 . Alternatively the measuring unit 42 can however be configured to buffer a measurement signal VM it has detected. The evaluation unit 46 can then detect the output signal VE irrespective of the time of detection of the measurement signal VM. It is however important that the measuring unit 42 detects the measurement signal VM within the camshaft angle range, which is bounded by the first camshaft angle NW 1 and the second camshaft angle NW 2 .
It is then verified in a step S 10 whether the voltage drop V over the inductive actuator drive 23 is greater than a predetermined threshold value THR. The predetermined threshold value THR is preferably determined by experiment or simulation, such that when the voltage drop V at the inductive actuator drive 23 exceeds the threshold value THR, this is characteristic of an induced voltage, which is characteristic of the pin 24 being pressed back out of the groove 25 due to the decrease in the depth of the groove 25 .
If the condition of step S 10 is not satisfied, processing continues directly in step S 4 . If however the condition of step S 10 is satisfied, in a step S 12 a logical variable LV_VL is assigned a low valve lift LO or a high valve lift HI according to the requirements specified in step S 2 for switching the valve lift VL. Processing then continues in a similar manner in step S 4 .
In the second unit 41 during operation of the internal combustion engine a program is processed, which is described in more detail below with reference to FIG. 6 . The program is started in a step S 20 , in which variables are optionally initialized. In a step S 22 a fuel mass to be injected MFF is determined as a function of an air mass flow MAF into the cylinder Z 1 , an air/fuel ratio in the cylinder Z 1 LAM and as a function of the value of the logical variable LV_VL. A control signal to activate the injection valve 28 is then generated as a function of the fuel mass to be injected MFF.
The waiting time T_W in step S 4 of the program, which is processed in the first unit 40 , is preferably selected such that it can be ensured that the logical variable LV_VL is always updated so promptly in step S 112 that the fuel mass to be injected MFF always has the correct values of the actual valve lift for the current operating cycle of the cylinder Z 1 in step S 22 to determine the fuel mass MFF.
In a step S 24 an ignition angle ZW is then determined as a function of the speed N, a required torque TQ_RQ, which is to be set by the internal combustion engine, and the value of the logical variable LV_VL. The required torque TQ_RQ is determined as a function of the detected accelerator pedal position and optionally further variables or torque requirements. The program is then halted in a step S 26 for the predetermined waiting time T_W, which can however be different from the waiting time in step S 4 .
FIG. 7 shows a further alternative block circuit diagram of parts of the controller 30 . R refers to a resistor, which is preferably designed to be high-resistance and is provided to detect the voltage drop V over the inductive actuator drive by means of the measuring unit 42 . Further inductive actuator drives, for example those assigned to different cylinders Z 2 to Z 4 , can also be connected in an electrically conductive manner at the node points A and B. If corresponding further second switches SW 2 are then provided, the measuring unit 42 can also be used to detect the respective voltage drop over the further inductive actuator drives.
The Zener diode D 2 ensures that the measurement signal VM of the measuring unit can be detected very quickly after the first switch SW 1 is opened.
With the controller 30 it is thus possible to identify any malfunction of the actuator element 20 and in particular the inductive actuator drive 23 due to an electrical or mechanical defect or incorrectly timed activation in a very simple manner. | The invention relates to an internal combustion engine comprising an inlet tract, leading to the inlet to a cylinder where a gas inlet valve is arranged. A valve drive for the gas inlet valve is provided, by means of which the valve stroke of the gas inlet may be adjusted using an actuator element, which permits differing cams to operate the gas inlet valve. An inductive actuator drive is arranged on the actuator element in which a voltage is induced during a switching process. A first unit is embodied for recognition of whether a switching of the valve stroke has occurred by means of the voltage induced in the inductive actuator drive which is characteristic of the switching process. A second unit is embodied for the control of at least one further actuator body depending on whether a switching of the valve is recognized in the first switching unit. | 5 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This patent application is a continuation of U.S. patent application Ser. No. 10/377,382, filed Feb. 28, 2003 now abandoned, which claims the benefit of U.S. Provisional Patent Application No. 60/360,673, filed Mar. 1, 2002.
FIELD OF THE INVENTION
The invention relates to a lightweight storage tank for fluids. More specifically, the invention relates to a fabric reinforced, thermoplastic coated, flexible container utilized, for example, for storage of liquid fuel, potable water or liquid hazardous waste.
BACKGROUND OF THE INVENTION
Flexible liquid storage tanks of relatively high capacity that exhibit a pillow- or sausage-like shape when filled are widely known as “pillow tanks.” They are typically composed of thermoplastic materials, such as polyether or polyester, and may include two or more layers of material. These tanks can be used to store, for example, gasoline, diesel fuel, jet fuel, potable water or hazardous liquid waste. Flexible storage tanks have the advantages of light weight and portability. Also, flexible storage tanks can be stored in a relatively small volume until needed.
However, conventional flexible storage tanks typically include seams, which are often the source of leakage. In particular, conventional flexible storage tanks are constructed in shapes that subject the seams of their flexible walls to stresses oriented perpendicularly to the flexible walls. These perpendicular stresses, widely known as “normal stresses,” are more difficult to seal against than “shearing stresses” (also known as “tangential stresses”).
For example, U.S. Pat. No. 3,453,164, issued to Gursky et al., describes a method of building fabric elastomeric containers in which a fabric is cut into strips and a tube is assembled by overlapping the edges of the strips in stitching to form individual seams. A liquid polyurethane reaction mixture and a material suitable for forming a fuel vapor barrier are applied to both sides of the assembled tube. Two end members are formed by folding pieces of the fabric into U-shapes. One of the U-shaped end members is cemented on each end of the tube to form a substantially rectangular container. Then each of the corners is trimmed to remove a triangle of fabric from each corner. Specially shaped and sized pieces of knit fabric are cemented over the trimmed areas to produce somewhat rounded corners, as indicated for knit fabric piece 41 in FIG. 4 of the Gursky et al. patent. However, as can be seen in FIG. 5 of the Gursky et al. patent, the finished container is still substantially rectangular in shape. Because neither this substantially rectangular shape nor the shape of fabric piece 41 matches the configuration of hydraulic forces within the container when it is filled with a liquid, at least some of the seams in the container of Gursky et al. patent are likely to be exposed to predominantly normal stresses.
A collapsible storage tank is described in U.S. Pat. No. 4,573,508, issued to Knaus, as including a substantially rectangular tank body composed of vulcanized inner and outer envelope structures. As can be seen in FIG. 3 of the Knaus patent, the collapsible storage tank includes rectangular corners and a peripheral seam that do not conform to the configuration of hydraulic forces that arise when the collapsible storage tank is filled with a liquid.
U.S. Pat. No. 3,919,030, issued to Jones, describes an elastic, fluid impervious storage tank having an intermediate section and a pair of end sections. Each of the end sections is reportedly formed from a single blank composed of a fiber-reinforced elastomer, which is cut and folded so that the corner portions are of rounded or arcuate configuration. The Jones et al. patent recites that this rounded corner portion greatly increases the strength of the storage tank, as compared to tanks having angular corner portions. According to the Jones patent, the cuts in the end section are closed by adhering a pre-formed arcuate inner attachment member 36 to the inside surface of the corner portion and, also adhering a pre-formed arcuate outer attachment 37 to the outer surface of each corner portion. The need to employ pre-formed members 36, 37 is a disadvantage in some situations. Also, it appears that any advantages associated with the storage tank of the Jones patent are limited to storage tanks that are small enough for the end sections to be constructed from one or two blanks of fabric material. Relatively larger tanks, which must necessarily be constructed of a number of fabric panels, are excluded.
A need exists for an improved flexible storage tank constructed in a configuration that is less susceptible to leaking when constructed of commonly available materials. Preferably, the improved tank is formed in shapes of revolution having relatively greater radii, as compared to conventional flexible storage tanks. Ideally, the seams of the improved tank are substantially under shearing stress, rather than normal stress, when the tank is filled with a liquid.
BRIEF SUMMARY OF THE INVENTION
The invention provides a soft shell, flexible storage tank, including corners of an improved configuration adapted to resist leaks. The corners are relatively more rounded and larger than those of conventional flexible tanks. Additionally, the walls of the tank are fabricated from thermoplastic panels joined in lapped seams by a heat treatment. The walls and the improved corners act together to resist leaks. The rounded corners tend to reduce the effective pressure in the tank walls by loading the seams predominantly in shearing stress when the tank is filled with a liquid.
The tank is especially resistant to leaks which might otherwise occur in the seams and adjacent the ends and corners of the tank. The tank is configured in relatively large-radius shapes of revolution which tend to place the seams in shearing stress, as opposed to normal stress. The shapes of revolution are developed as panels, which are thermally bonded to produce secure and reliable liquid-tight seams. Each of the panels is bonded by lapped seams to others of the panels.
In developing the panels, allowance may be made for panel stretching under the influence of gravity and hydraulic pressure, over a specific range of ambient temperature and storage fluid density. The total number of panels and length of seams are other factors to consider.
The tank is unique in that it includes specially rounded corners, sometimes called “elegant corners.” In effect, the flexible storage tank functions as a pressure vessel, which tends to resist leakage. Each of the rounded corners includes four panels. One of the four panels is generally triangular, being bounded by three curved edges. Each of the curved edges is bonded by a lapped seam with one of the four panels. The rounded corner is generally ellipsoidal when the tank is filled with a liquid.
The tanks are formed from panels composed of thermoplastic material. The panels are sealed, effectively welded together, by an application of heat. Flexible urethane material is used for the tank, preferably polyether or polyester, most preferably polyether. Additionally, the edges of the panels are filled up with a film of rubber gum to further reduce leakage. The resulting seams are superior to conventional seams that have previously been created by use of glue or solvents. The tanks are suitable for use with water and aromatic storage liquids.
The corners of the tank are built-up by joining thermoplastic panels. While this may increase the time required to make the tank, the improved rounded corners reduce the effect of pressure from liquid that occurs in the corners of the tank. This reduces the possibility of leakage. The elegant corner does not concentrate stress at any point in the corner.
In order to make a flexible storage tank of the present invention, one or more sheets composed essentially of a thermoplastic material and a fabric layer are cut to produce panels of various shapes. A number of top panels of approximately equal length and generally rectangular shape are produced in this manner. Bottoms panels of approximately the same length as the top panels and generally rectangular shape are also fashioned from one or more sheets. Side panels are cut to a length less than that of the top panels and the bottom panels. Generally triangular panels are shaped so as to be bounded by three curved edges.
These panels are assembled by bonding the top panels to each other to produce a generally rectangular topside assembly. The bottom panels are bonded to each other to each other to produce a generally rectangular bottomside assembly. Each of the ends of the top panels is bonded, respectively, with one of the ends of the bottom panels. The triangular panels are attached by a lapped seam bonding each of the curved edges with one of the top panels, one of the bottom panels or one of the side panels to produce a flexible storage tank having rounded corners.
Previously known similar products were called “pillow tanks”. They had somewhat rounded corners, but used cement to form the seams and were configured in a different geometry than the tank of the instant invention. They were more prone to leakage than the tanks of the present invention.
The improved tank is made in various sizes. In order to reduce the cost of construction, the width of the various sizes of tank is fixed and the volume is adjusted by varying the length of the particular tank. In this way, the tank sizes are expandable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a 50,000-gallon flexible fuel storage tank 100 ;
FIG. 2 is an elevation end view of the tank depicted in FIG. 1 ;
FIG. 3 is a development of panel 1 for the tank depicted in FIG. 1 ;
FIG. 4 is a development of panel 2 for the tank depicted in FIG. 1 ;
FIG. 5 is a development of panel 3 for the tank depicted in FIG. 1 ;
FIG. 6 is a development of panel 4 for the tank depicted in FIG. 1 ;
FIG. 7 is a development of panel 5 for the tank depicted in FIG. 1 ;
FIG. 8 is a development of panel 6 for the tank depicted in FIG. 1 ;
FIG. 9 is a development of panel 7 for the tank depicted in FIG. 1 ;
FIG. 10 is a development of panel 8 for the tank depicted in FIG. 1 ;
FIG. 11 is a development of panel 9 for the tank depicted in FIG. 1 ;
FIG. 12 is a development of panel 10 for the tank depicted in FIG. 1 ;
FIG. 13 is a development of panel 11 for the tank depicted in FIG. 1 ;
FIG. 14 is a development of accessories for the tank depicted in FIG. 1 ;
FIG. 15 is an assembly drawing for the tank depicted in FIG. 1 ;
FIG. 16 is a partial perspective view of tube 50 constituted by panels 1 – 11 according to the invention;
FIG. 17 is a partial perspective view of tube 50 with top panels 1 , 2 , 3 , 10 and 11 and bottom panels 5 – 8 joined in a closed end;
FIG. 18 is a partial perspective view of tank 100 showing the placement of triangular panels 15 , 16 ; and
FIG. 19 is a partial side view of tank 100 drawn to scale, with a human figure (not part of the invention) included to convey the size of tank 100 .
DETAILED DESCRIPTION OF THE INVENTION
In a preferred embodiment, the invention provides a flexible, soft shell, fuel storage tank 100 , as depicted in FIGS. 1–15 . Tank 100 is useful for containing, for example, diesel fuel or jet fuel and has a capacity of 50,000 United States gallons. Tank 100 is adapted to resist leaks over a range of operating temperature up to about 130 degrees F.
Referring now to FIG. 1 , tank 100 is of lapped seam construction with seams 13 extending along the length of tank 100 . A “lapped seam,” also known as a lapped joint, means a seam made by lapping one piece or part over another and fastening them together. Corners 12 of tank 100 are noticeably rounded, and built-up employing several panels 1 – 11 , 15 – 18 of definite shape. The improvement afforded by rounded corners 12 is analogous to that found in rounded pressure vessels.
As depicted in FIG. 2 , panels 1 – 11 , 15 – 18 are composed of a layer of thermoplastic material, such as polyester or polyether, and a fabric layer. Other materials may be employed based, among other things, on the physical and chemical characteristics of the liquid intended for storage and the expected operating temperature conditions. Seams 13 of tank 100 are sealed by applying heat to the thermoplastic material. The resulting welded seam 13 is superior to seams formed by applying glues or solvents.
While tank 100 is a 50,000 gallon tank, tanks of other capacities may be easily fashioned by employing the same end dimensions and adjusting the lengths of the respective panels.
Tank 100 is 64½ feet long and 23 feet wide when filled. Tank 100 includes two manways 22 for inspection and cleaning. Each of the manways 22 is located six feet from an end of tank 100 . Tank 100 also includes two floor cutouts 24 , two floor drains 27 and a vent 28 , which is fitted with a flame arrestor (not shown). Filling is accomplished through one or more of the manways 22 via a flexible filler hose of 4 inches diameter.
As shown in FIG. 2 , tank 100 has a generally elliptical transverse cross-section, bounded by panels 1 – 11 , 15 – 18 . Panels 1 – 11 are numbered sequentially beginning at the top center line of tank 100 and proceeding in a clockwise direction, as depicted in FIG. 2 . Each of panels 1 – 11 is symmetrical with regard to a center line that is perpendicular to the length of the respective panel.
In order to better communicate the invention, panels 1 , 2 , 3 , 10 and 11 are referred to as top panels, together forming topside assembly 56 (best seen in FIG. 16 ). Top panels 1 , 2 , 3 , 10 and 11 , are all between 66 and 67 feet in length, and are about 4 and ½ feet in width, although not all are exactly rectangular. Panels 5 – 8 are referred to as bottom panels, together forming bottomside assembly 58 (best seen in FIG. 16 ). Bottom panels 5 – 8 are all about 65 feet in length, and about 4 and ½ feet in width, although they are exactly rectangular. Panels 4 and 9 are referred to as side panels, each having a length of less than about 60 and a width of about 4 and ½ feet, although they are not exactly rectangular. Joining each of the side panels 4 , 9 , respectively to topside assembly 56 and to bottomside assembly 58 produces flexible tube 50 (best seen in FIG. 16 ).
Each of panels 15 – 18 is generally triangular and bounded by three of curved edges 30 – 41 , as described below. Tank 100 is 5½ feet in height when filled and is provided with thirty-two handles, for use in folding, positioning or securing tank 100 .
FIGS. 3–13 depict developments of panels 1 – 11 , 15 – 18 , which illustrate details for each of panels 1 – 11 , 15 – 18 . Referring to FIG. 3 , panel 1 is in the shape of a rectangle 66 feet and 10¼ inches long and 4⅔ feet wide. A 3-inch wide seam area is designated along each end of panel 1 . A vent cutout 29 is located at the intersection of the center-lines of rectangular panel 1 .
As shown in FIG. 4 , panel 2 has a generally rectangular, six-sided shape cut from a rectangle 4⅔ feet wide and 66 feet and 10¼ inches long. Panel 2 has one straight edge 66 feet and 5⅝ inches in length. Panel 2 has a second straight edge of length 48 feet and 10½ inches in length, centered on and parallel to the first straight edge at a distance of 4 feet and 8 inches. The ends of panel 2 are slightly obtuse with respect to the first straight edge, each extending from the first straight edge to a terminus located 4 feet and 5¼ inches transversely from the first straight edge and 66 feet and 10¼ inches from the terminus of the opposite end. Two additional straight edges, each measuring 8 feet and 11⅞ inches connect the ends with the second straight edge. A 3-inch wide seam area is designated along each end of panel 2 . A manway cutout 26 is located at the intersection of the axial center of panel 2 , about six and a half feet from the nearest end.
FIG. 5 depicts panel 3 , which may be cut from a rectangle 66 feet and 4 and 3/16 inches long and 4 feet and 5 and ¼ inches wide. Panel 3 has two centrally located, parallel edges of length 52 feet and 5 and ¾ inches and 48 feet and 3 and ¾ inches, respectively. A seam area 2 and ½ inches wide is designated along the shorter of these parallel edges. Each of the ends of panel 3 is an oblique straight edge having a length of 2 feet and 6 and 15/16 inches. A seam area having a width of 3 inches is designated along each of the straight edge ends of panel 3 . The straight edge ends are connected to the parallel edges by curves, as shown in FIG. 5 .
Panel 4 and separate triangular panels 15 , 17 are depicted in FIG. 6 . Panels 4 , 15 and 17 are shown together in FIG. 6 to emphasize that all three may be cut from a single rectangular sheet that is 66 feet and 5 inches long and 4 feet and 5 and ¼ inches wide. Panel 4 , which is one of the side panels 4 , 9 , is generally rectangular with an overall length of 59 feet and 8 and ⅞ inches. A seam area having a width of 2 and ½ inches is designated along three of the edges of panel 4 .
Continuing with FIG. 6 , panels 15 and 17 are mirror images of each other. Each of the panels 15 , 17 is generally triangular in shape and bounded by three curved edges. A triangle inscribed within and sharing the vertices of panel 15 would have one altitude of about 2 feet and 4 inches and another altitude of about 4 feet and 3 inches. A seam area 2 and ½ inches wide is designated along intermediate length curved edges 31 , 37 of panels 15 , 17 , respectively.
As depicted in FIG. 7 , panel 5 is generally rectangular with a length of 64 feet and 10 and 13/16 inches and a width of 4 feet and 8 inches. Drain cutout 24 is located 5 and ½ feet from the nearest end.
Panel 6 , shown in FIG. 8 , is generally rectangular with a length of about 64 feet and 10 and ½ inches and a width 4 feet and 8 inches.
Panel 7 , which is depicted in FIG. 9 , is the mirror image of panel 6 .
Panel 8 , which is depicted in FIG. 10 , is the mirror image of panel 5 .
Panel 9 , which is depicted in FIG. 11 , is the mirror image of panel 4 . Panels 16 and 17 , which are also depicted in FIG. 11 , are the mirror images of panels 15 and 17 , respectively
Panel 10 , which is depicted in FIG. 12 , is the mirror image of panel 3 .
Panel 11 , which is depicted in FIG. 13 , is the mirror image of panel 2 .
FIG. 14 illustrates accessory panels, which may be optionally be used in constructing tank 100 . For example, the legend “MW CHAF 37 ” in FIG. 14 designates a chaffing pad to be located directly beneath one of the manways 22 .
FIG. 15 is an assembly drawing, which depicts the manner in which panels 1 – 11 are joined with regard to each other. More specifically, a preferred method of making tank 100 includes joining each of panels 1 – 11 to two others of panels 1 – 11 by thermally bonded. lapped seams 13 in the relationship illustrated in FIG. 15 . Seams 13 may be bonded in any order; preferably, panels 6 and panel 7 are the last of this group to be bonded.
Bonding panels 1 – 11 along their edges produces tube 50 , as depicted in FIG. 16 . Panels 1 , 2 , 3 , 10 , and 11 , together, constitute topside assembly 56 . Panels 5 – 8 , together, constitute bottomside assembly 58 . Side panels 4 , 9 join the two assemblies 56 , 58 to each other. Tube 50 includes end 52 , which is shown in FIG. 16 , and end 54 (not shown.).
After tube 50 has been assembled, the ends of top panels 1 , 2 , 3 , 10 , and 11 each may be bonded, respectively, with the ends of one of bottom panels 5 – 8 . This bonding substantially closes end 52 of tube 50 , as shown in FIG. 17 , and end 54 (not shown). However, as can be seen in FIG. 17 , openings still remain.
FIG. 18 depicts triangular panels 15 , 16 positioned and bonded to complete the closing of end 52 of tube 50 . Triangular panels 17 , 18 (best seen in FIG. 11 ) are similarly positioned and bonded to close end 54 (not shown). Curved edge 30 , which is the shortest edge of panel 15 , bonds to panel 3 . Curved edge 31 , which is of intermediate length in panel 15 bonds to panel 5 . Curved edge 32 , which is the longest edge of panel 15 , bonds to panel 4 . Each the curved edges 30 , 31 , 32 , respectively, is thermally bonded in a lapped seam 13 with one of panels 3 , 5 , 4 to complete one of the rounded corners 12 .
When assembled, tank 100 comprises 3500 square feet of coated fabric and weighs 1,080 pounds. Because seams 13 of tank 100 are substantially under shearing stress, rather than normal stress, tank 100 tends to resist leakage when filled with a storage liquid.
While only a few, preferred embodiments of the invention have been described above, those of ordinary skill in the art will recognize that these embodiments may be modified and altered without departing from the central spirit and scope of the invention. The preferred embodiments described above are to be considered in all respects as illustrative and not restrictive. | A soft shell, flexible storage tank is provided, including corners of an improved configuration adapted to resist leaks. The walls of the tank and the corners are relatively more rounded and larger in radius than those of conventional flexible tanks. The walls and the improved corners act together to resist leaks. The rounded corners tend to reduce the effective pressure in the tank walls by loading the seams predominantly in shearing stress when the tank is filled with a liquid. The rounded corners are developed as panels, which are thermally bonded to produce secure and reliable liquid-tight seams. Each of the panels is bonded by lapped seams to others of the panels. Each of the rounded corners includes a generally triangular corner that is bonded to at least three other panels. In effect, the flexible storage tank functions as a pressure vessel, which tends to resist leakage. | 1 |
CROSS REFERENCE
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/088,217 filed on Aug. 12, 2008, the entire disclosure of which is incorporated herein by this specific reference.
FIELD OF THE INVENTION
The present invention relates generally to certain substituted benzamides and to their use as antagonists, for example as antagonists of sphingosine-1-phosphate receptors. The invention relates specifically to the use of these compounds and pharmaceutical compositions to treat disorders associated with sphingosine-1-phosphate receptor modulation.
BACKGROUND OF THE INVENTION
Sphingosine is a compound having the chemical structure shown in the general formula described below, in which Y 1 is hydrogen. It is known that various sphingolipids, having sphingosine as a constituent, are widely distributed in the living body including on the surface of cell membranes of cells in the nervous system.
A sphingolipid is one of the lipids having important roles in the living body. A disease called lipidosis is caused by accumulation of a specified sphingolipid in the body. Sphingolipids present on cell membranes function to regulate cell growth; participate in the development and differentiation of cells; function in nerves; are involved in the infection and malignancy of cells; etc. Many of the physiological roles of sphingolipids remain to be solved. Recently the possibility that ceramide, a derivative of sphingosine, has an important role in the mechanism of cell signal transduction has been indicated, and studies about its effect on apoptosis and cell cycle have been reported.
Sphingosine-1-phosphate is an important cellular metabolite, derived from ceramide that is synthesized de novo or as part of the sphingomeyeline cycle (in animals cells). It has also been found in insects, yeasts and plants.
The enzyme, ceramidase, acts upon ceramides to release sphingosine, which is phosphorylated by sphingosine kinase, a ubiquitous enzyme in the cytosol and endoplasmic reticulum, to form sphingosine-1-phosphate. The reverse reaction can occur also by the action of sphingosine phosphatases, and the enzymes act in concert to control the cellular concentrations of the metabolite, which concentrations are always low. In plasma, such concentration can reach 0.2 to 0.9 μM, and the metabolite is found in association with the lipoproteins, especially the HDL. It should also be noted that sphingosine-1-phosphate formation is an essential step in the catabolism of sphingoid bases.
Like its precursors, sphingosine-1-phosphate is a potent messenger molecule that perhaps uniquely operates both intra- and inter-cellularly, but with very different functions from ceramides and sphingosine. The balance between these various sphingolipid metabolites may be important for health. For example, within the cell, sphingosine-1-phosphate promotes cellular division (mitosis) as opposed to cell death (apoptosis), which it inhibits. Intracellularly, it also functions to regulate calcium mobilization and cell growth in response to a variety of extracellular stimuli. Current opinion appears to suggest that the balance between sphingosine-1-phosphate and ceramide and/or sphingosine levels in cells is critical for their viability. In common with the lysophospholipids, especially lysophosphatidic acid, with which it has some structural similarities, sphingosine-1-phosphate exerts many of its extra-cellular effects through interaction with five specific G protein-coupled receptors on cell surfaces. These are important for the growth of new blood vessels, vascular maturation, cardiac development and immunity, and for directed cell movement.
Sphingosine-1 phosphate is stored in relatively high concentrations in human platelets, which lack the enzymes responsible for its catabolism, and it is released into the blood stream upon activation of physiological stimuli, such as growth factors, cytokines, and receptor agonists and antigens. It may also have a critical role in platelet aggregation and thrombosis and could aggravate cardiovascular disease. On the other hand the relatively high concentration of the metabolite in high-density lipoproteins (HDL) may have beneficial implications for atherogenesis. For example, there are recent suggestions that sphingosine-1-phosphate, together with other lysolipids such as sphingosylphosphorylcholine and lysosulfatide, are responsible for the beneficial clinical effects of HDL by stimulating the production of the potent antiatherogenic signaling molecule nitric oxide by the vascular endothelium. In addition, like lysophosphatidic acid, it is a marker for certain types of cancer, and there is evidence that its role in cell division or proliferation may have an influence on the development of cancers. These are currently topics that are attracting great interest amongst medical researchers, and the potential for therapeutic intervention in sphingosine-1-phosphate metabolism is under active investigation.
Fungi and plants have sphingolipids and the major sphingosine contained in these organisms has the formula described below. It is known that these lipids have important roles in the cell growth of fungi and plants, but details of the roles remain to be solved.
Recently it has been known that derivatives of sphingolipids and their related compounds exhibit a variety of biological activities through inhibition or stimulation of the metabolism pathways. These compounds include inhibitors of protein kinase C, inducers of apoptosis, immuno-suppressive compounds, antifungal compounds, and the like. Substances having these biological activities are expected to be useful compounds for various diseases.
Derivatives of sphingosine have been prepared in various patents. For example, see U.S. Pat. Nos. 4,952,683; 5,110,987; 6,235,912 B1 and 6,239,297 B1.
Also, compounds which are similar to certain sphingosine derivatives, but which are not reported as being ligands for the sphingosine receptors are reported in various patents and published patent applications. See for example, U.S. Pat. Nos. 5,294,722; 5,102,901; 5,403,851 and 5,580,878. U.S. Patent Application Publication No. U.S. 2003/0125371 A2.
SUMMARY OF THE INVENTION
The invention provides certain well-defined benzamides that are useful as sphingosine-1-phosphate antagonists. As such, the compounds described herein are useful in treating a wide variety of disorders associated with modulation of sphingosine-1-phosphate receptors.
In one embodiment of the invention, there are provided compounds having the structure
wherein:
each R 1 is independently —H or lower alkyl; each R 2 and R 3 are independently —H, straight or branched chain alkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, alkenyl, alkynyl, halide, hydroxy, alkoxy, alkylamino, alkylcarboxyl, trifluoromethyl, —N(R 4 ) 2 , —CN, —CO 2 R 4 , —CH 2 OH, —OCF 3 , —OCHF 2 , or —NO 2 ; wherein each R 2 is in the meta- or para-position relative to the carbonyl moiety; each R 4 is independently H, straight or branched chain alkyl, cycloalkyl, aryl, heteroaryl, haloalkyl, hydroxy, alkoxy, hydroxyalkyl, alkylcarbonyl, formyl, oxycarbonyl, carboxyl, alkyl carboxylate, alkylamide, amino, alkylamino, or aminocarbonyl; Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 are each independently C, N, O, or S; X is H, F, Cl, Br, or I; each n is independently 1-5; and p is 0 or 1;
with the proviso that when Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 are each C, p is 1, and each R 2 is —H, R 3 is not Cl;
or pharmaceutically acceptable salts thereof.
In another embodiment, there are provided pharmaceutical compositions including at least one compound of the invention in a pharmaceutically acceptable carrier therefor.
In a further embodiment of the invention, there are provided methods for treating disorders associated with modulation of sphingosine-1-phosphate receptors. Such methods can be performed, for example, by administering to a subject in need thereof a pharmaceutical composition containing a therapeutically effective amount of at least one compound of the invention.
In still another embodiment of the invention, there are provided methods for treating disorders associated with modulation of sphingosine-1-phosphate receptors including S1P1, S1P2 and S1P3 receptors. Such methods can be performed, for example, by administering to a subject in need thereof a therapeutically effective amount of at least one compound of the invention, or any combination thereof, or pharmaceutically acceptable salts, hydrates, solvates, crystal forms and individual isomers, enantiomers, and diastereomers thereof.
DETAILED DESCRIPTION OF THE INVENTION
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention claimed. As used herein, the use of the singular includes the plural unless specifically stated otherwise. As used herein, “or” means “and/or” unless stated otherwise. Furthermore, use of the term “including” as well as other forms, such as “includes,” and “included,” is not limiting. The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.
Unless specific definitions are provided, the nomenclatures utilized in connection with, and the laboratory procedures and techniques of analytical chemistry, synthetic organic and inorganic chemistry described herein are those known in the art. Standard chemical symbols are used interchangeably with the full names represented by such symbols. Thus, for example, the terms “hydrogen” and “H” are understood to have identical meaning. Standard techniques may be used for chemical syntheses, chemical analyses, and formulation.
As used herein, “alkyl” refers to straight, branched chain or cyclic hydrocarbyl groups having from 1 up to about 100 carbon atoms. Whenever it appears herein, a numerical range, such as “1 to 100” or “C 1 -C 100 ”, refers to each integer in the given range; e.g., “C 1 -C 100 alkyl” means that an alkyl group may comprise only 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., up to and including 100 carbon atoms, although the term “alkyl” also includes instances where no numerical range of carbon atoms is designated. “Substituted alkyl” refers to alkyl moieties bearing substituents typically selected from alkyl, alkenyl, alkynyl, hydroxy, alkoxy, heterocyclic, aryl, heteroaryl, aryloxy, halogen, haloalkyl, cyano, nitro, amino, lower alkylamino, lower dialkylamino, amido, azido, acyl (—C(O)R 6 ), alkoxymethyl, mercapto (—S—R 6 ), sulfoxy (—S(O)—R 6 ), sulfonyl (—S(O) 2 —R 6 ), sulfonamide (—S(O) 2 N(R 6 ) 2 ), carbonate (—OC(O)—O—R 6 ), oxyacyl
(—OC(O)—R 6 ), carboxyl (—C(O)OH), ester (—C(O)OR 6 ), carbamate (—OC(O)—N(R 6 ) 2 ), wherein R 6 is H or lower alkyl, lower alkenyl, lower alkynyl, aryl, heteroaryl, heterocycle, and the like. As used herein, “lower alkyl” refers to alkyl moieties having from 1 to about 6 carbon atoms.
As used herein, “alkenyl” refers to straight, branched chain or cyclic hydrocarbyl groups having at least one carbon-carbon double bond, and having in the range of about 2 up to about 100 carbon atoms, and “substituted alkenyl” refers to alkenyl groups further bearing one or more substituents as set forth above. As used herein, “lower alkenyl” refers to alkenyl moieties having from 1 to about 6 carbon atoms.
As used herein, “alkynyl” refers to straight or branched chain hydrocarbyl groups having at least one carbon-carbon triple bond, and having in the range of about 2 up to about 100 carbon atoms, and “substituted alkynyl” refers to alkynyl groups further bearing one or more substituents as set forth above. As used herein, “lower alkynyl” refers to alkynyl moieties having from 2 to about 6 carbon atoms.
As used herein, “cycloalkyl” refers to cyclic (i.e., ring-containing) alkyl moieties typically containing in the range of about 3 up to about 8 carbon atoms, and “substituted cycloalkyl” refers to cycloalkyl groups further bearing one or more substituents as set forth above.
As used herein, “aryl” refers to aromatic groups having in the range of 6 up to 14 carbon atoms and “substituted aryl” refers to aryl groups further bearing one or more substituents as set forth above.
As used herein, “heteroaryl” refers to aromatic moieties containing one or more heteroatoms (e.g., N, O, S, or the like) as part of the ring structure and having in the range of 5 up to 14 total atoms in the ring structure (i.e., carbon atoms and heteroatoms). “Substituted heteroaryl” refers to heteroaryl groups further bearing one or more substituents as set forth above.
As used herein, “heterocyclic” or “heterocycle” refers to non-aromatic cyclic (i.e., ring-containing) groups containing one or more heteroatoms (e.g., N, O, S, or the like) as part of the ring structure, and having in the range of 3 up to 14 carbon atoms and “substituted heterocyclic” or “substituted heterocycle” refers to heterocyclic groups or heterocycles further bearing one or more substituents as set forth above.
As used herein, “halogen” or “halide” refers to fluoride, chloride, bromide or iodide. The terms “fluoro”, “chloro”, “bromo”, and “iodo” may also be used when referring to halogenated substituents, for example, “trifluoromethyl.”
As used herein, “hydroxyalkyl” refers to alkyl-OH, such as hydroxymethyl, hydroxyethyl, and the like.
As used herein, “alkylacyl” refers to an alkyl ketone such as ethanone, propanone, and the like.
As used herein, “pharmaceutically acceptable salt” refers to those salts which retain the biological effectiveness and properties of the free bases and which are obtained by reaction with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonic acid,
p-toluenesulfonic acid, salicylic acid and the like.
It will be readily apparent to those skilled in the art that some of the compounds of the invention may contain one or more asymmetric centers, such that the compounds may exist in enantiomeric as well as in diastereomeric forms. Unless it is specifically noted otherwise, the scope of the present invention includes all enantiomers, diastereomers and racemic mixtures. Some of the compounds of the invention may form salts with pharmaceutically acceptable acids or bases, and such pharmaceutically acceptable salts of the compounds described herein are also within the scope of the invention.
The invention provides compounds having the structure:
wherein:
each R 1 is independently —H or lower alkyl; each R 2 and R 3 are independently —H, straight or branched chain alkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, alkenyl, alkynyl, halide, hydroxy, alkoxy, alkylamino, alkylcarboxyl, trifluoromethyl, —N(R 4 ) 2 , —CN, —CO 2 R 4 , —CH 2 OH, —OCF 3 , —OCHF 2 , or —NO 2 ; wherein each R 2 is in the meta- or para-position relative to the carbonyl moiety; each R 4 is independently H, straight or branched chain alkyl, cycloalkyl, aryl, heteroaryl, haloalkyl, hydroxy, alkoxy, hydroxyalkyl, alkylcarbonyl, formyl, oxycarbonyl, carboxyl, alkyl carboxylate, alkylamide, amino, alkylamino, or aminocarbonyl; Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 are each independently C, N, O, or S; X is H, F, Cl, Br, or I; each n is independently 1-5; and p is 0 or 1;
with the proviso that when Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 are each C, p is 1, and each R 2 is —H, R 3 is not Cl;
or pharmaceutically acceptable salts thereof.
In some embodiments of the invention, X is F, Cl or Br.
In some embodiments, each R 2 is independently alkyl, halide, alkoxy, or —NO 2 .
In one embodiment the structure on the prior page optionally excludes one or all of the following compounds:
In certain embodiments of the invention, there are provided compounds having the structure
wherein:
X is Cl or Br; R 2 and each R 3 are independently —H, straight or branched chain alkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, alkenyl, alkynyl, halide, hydroxy, alkoxy, alkylamino, alkylcarboxyl, trifluoromethyl, —N(R 4 ) 2 , —CN, —CO 2 R 4 , —CH 2 OH, —OCF 3 , —OCHF 2 , or —NO 2 ; each R 4 is independently H, straight or branched chain alkyl, cycloalkyl, aryl, heteroaryl, haloalkyl, hydroxy, alkoxy, hydroxyalkyl, alkylcarbonyl, formyl, oxycarbonyl, carboxyl, alkyl carboxylate, alkylamide, amino, alkylamino, or aminocarbonyl; and n is 1-5.
In certain embodiments of the invention there are provided compounds having the structure
wherein:
X is Cl, F or Br; R 2 and each R 3 are independently —H, straight or branched chain alkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, alkenyl, alkynyl, halide, hydroxy, alkoxy, alkylamino, alkylcarboxyl, trifluoromethyl, —N(R 4 ) 2 , —CN, —CO 2 R 4 , —CH 2 OH, —OCF 3 , —OCHF 2 , or —NO 2 ; each R 4 is independently H, straight or branched chain alkyl, cycloalkyl, aryl, heteroaryl, haloalkyl, hydroxy, alkoxy, hydroxyalkyl, alkylcarbonyl, formyl, oxycarbonyl, carboxyl, alkyl carboxylate, alkylamide, amino, alkylamino, or aminocarbonyl; and n is 1-5.
In other embodiments, there are provided compounds wherein p is 1 and Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 are each C. Compounds according to this embodiment of the invention include, but are not limited to, compounds having any one of the structures:
In other embodiments, there are provided compounds wherein p is 0, Z 1 is O, and Z 3 , Z 4 , Z 5 , and Z 6 are each C. Compounds according to this embodiment of the invention include, but are not limited to, compounds having any one of the structures:
In other embodiments, there are provided compounds wherein p is 1 and at least one of Z 1 , Z 2 , Z 3 , Z 4 , Z 5 , and Z 6 is N. Compounds according to this embodiment of the invention include, but are not limited to, compounds having any one of the structures:
The compounds of the invention can be prepared in a variety of ways well known to those skilled in the art. Scheme A set forth below outlines an exemplary synthetic route to the compounds of the invention.
The compounds of the invention can be synthesized by variations on methods described by Guirado, A. et al; Tetrahedron, 58, 2002, 5087 and from other sources cited therein. For example, referring to Scheme A, action of chloral in the presence of an amide underwent smooth transition to the alcohol. The alcohols can be converted to the chloride with a suitable reagent such as PCl 5 , SOCl 2 , or the like. The final step is a reaction of the chloride with a suitable amine under mild conditions followed by appropriate workup and purification procedures well known to those skilled in the art.
The compounds of the invention were tested for S1P3 activity using the Flipr assay. The compounds may be assessed for ability to activate or block activation of the human S1P3 receptor in T24 cells stably expressing the human S1P3 receptor. Ten thousand cells/well are plated into 384-well poly-D-lysine coated plates one day prior to use. The growth media for the S1P3 receptor expressing cell line McCoy's 5A medium supplemented with 10% charcoal-treated fetal bovine serum (FBS), 1% antibiotic-antimycotic and 400 μg/mL genetecin. On the day of the experiment, the cells are washed twice Hank's Balanced Salt Solution supplemented with 20 mM HEPES (HBSS/Hepes buffer). The cells are then dye loaded with 2 μM Fluo-4 diluted in the HBSS/Hepes buffer with 1.25 mM Probenecid and incubated at 37° C. for 40 minutes. Extracellular dye is removed by washing the cell plates four times prior to placing the plates in the FLIPR (Fluorometric Imaging Plate Reader, Molecular Devices). Ligands are diluted in HBSS/Hepes buffer and prepared in 384-well microplates. The positive control, Sphingosine-1-phosphate (SIP), is diluted in HBSS/Hepes buffer with 4 mg/mL fatty acid free bovine serum albumin. The FLIPR transfers 12.5 μL from the ligand microplate to the cell plate and takes fluorescent measurements for 75 seconds, taking readings every second, and then for 2.5 minutes, taking readings every 10 seconds. Drugs are tested over the concentration range of 0.61 nM to 10,000 nM. Data for Ca +2 responses are obtained in arbitrary fluorescence units and not translated into Ca +2 concentrations. IC 50 values are determined through a linear regression analysis using the Levenburg Marquardt algorithm. The results of the assay are set forth in the table below.
%
An-
Biological Data
IC50
tago-
Activity potency human S1P3 receptor from FLIPR
nM
nism
1370
93
148
97
278
96
1520
94
492
94
28
96
73
100
466
98
1450
91
145
100
1140
76
98
100
2988
100
110
95
454
100
291
98
711
95
430
99
1400
102
1100
98
1180
95
1470
41
270
98
363
100
1410
56
365
98
498
99
245
97
2
99
NA
—
16
96
256
95
9.5
90
1.4
99
4.7
99
6.3
98
1650
99
Diseases that may be treated with the compounds, compositions, and methods of the invention include, but are not limited to the following conditions:
Allergies and other inflammatory diseases: Urticaria, bronchial asthma, and other airway inflammations including pulmonary emphysema and chronic obstructive pulmonary diseases;
Cardiac functions: bradycardia, congestional heart failure, cardiac arrhythmia, prevention and treatment of atherosclerosis, and ischemia/reperfusion injury;
Anti-fibrosis: ocular, cardiac, hepatic and pulmonary fibrosis, proliferative vitreoretinopathy, cicatricial pemphigoid, surgically induced fibrosis in cornea, conjunctiva and tenon; and
Pains and Inflammatory diseases: Acute pain, flare-up of chronic pain, musculo-skeletal pains, visceral pain, pain associated with diabetic neuropathy, rheumatoid arthritis, chronic knee and joint pain, tendonitis, osteoarthritis, bursitis, neuropathic pains.
The compounds of the invention may be administered at pharmaceutically effective dosages. Such dosages are normally the minimum dose necessary to achieve the desired therapeutic effect; in the treatment of chromic pain, this amount would be roughly that necessary to reduce the discomfort caused by the pain to tolerable levels. Generally, such doses will be in the range 1-1000 mg/day; more preferably in the range 10 to 500 mg/day. However, the actual amount of the compound to be administered in any given case will be determined by a physician taking into account the relevant circumstances, such as the severity of the pain, the age and weight of the patient, the patient's general physical condition, the cause of the pain, and the route of administration.
The compounds are useful in the treatment of pain in a mammal; particularly a human being. Both acute pain and chronic pain may be treated by administration of the compounds and compositions of the invention. By “acute pain” is meant immediate, usually high threshold, pain brought about by injury such as a cut, crush, burn, or by chemical stimulation such as that experienced upon exposure to capsaicin, the active ingredient in chili peppers. By “chronic pain” is meant pain other than acute pain, such as, without limitation, neuropathic pain, visceral pain (including that brought about by Crohn's disease and irritable bowel syndrome (IBS)), and referred pain.
Preferably, the patient will be administered the compound orally in any acceptable form, such as a tablet, liquid, capsule, powder and the like. However, other routes may be desirable or necessary, particularly if the patient suffers from nausea. Such other routes may include, without exception, transdermal, parenteral, subcutaneous, intranasal, intrathecal, intramuscular, intravenous, and intrarectal modes of delivery. Additionally, the formulations may be designed to delay release of the active compound over a given period of time, or to carefully control the amount of drug released at a given time during the course of therapy.
In another embodiment of the invention, there are provided pharmaceutical compositions including at least one compound of the invention in a pharmaceutically acceptable carrier therefor. The phrase “pharmaceutically acceptable” means the carrier, diluent or excipient must be compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.
Pharmaceutical compositions of the present invention can be used in the form of a solid, a solution, an emulsion, a dispersion, a micelle, a liposome, and the like, wherein the resulting composition contains one or more compounds of the present invention, as an active ingredient, in admixture with an organic or inorganic carrier or excipient suitable for enteral or parenteral applications. Invention compounds may be combined, for example, with the usual non-toxic, pharmaceutically acceptable carriers for tablets, pellets, capsules, suppositories, solutions, emulsions, suspensions, and any other form suitable for use. The carriers which can be used include glucose, lactose, gum acacia, gelatin, mannitol, starch paste, magnesium trisilicate, talc, corn starch, keratin, colloidal silica, potato starch, urea, medium chain length triglycerides, dextrans, and other carriers suitable for use in manufacturing preparations, in solid, semisolid, or liquid form. In addition auxiliary, stabilizing, thickening and coloring agents and perfumes may be used. Invention compounds are included in the pharmaceutical composition in an amount sufficient to produce the desired effect upon the process or disease condition.
Pharmaceutical compositions containing invention compounds may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of a sweetening agent such as sucrose, lactose, or saccharin, flavoring agents such as peppermint, oil of wintergreen or cherry, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets containing invention compounds in admixture with non-toxic pharmaceutically acceptable excipients may also be manufactured by known methods. The excipients used may be, for example, (1) inert diluents such as calcium carbonate, lactose, calcium phosphate or sodium phosphate; (2) granulating and disintegrating agents such as corn starch, potato starch or alginic acid; (3) binding agents such as gum tragacanth, corn starch, gelatin or acacia, and (4) lubricating agents such as magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed.
In some cases, formulations for oral use may be in the form of hard gelatin capsules wherein the invention compounds are mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin. They may also be in the form of soft gelatin capsules wherein the invention compounds are mixed with water or an oil medium, for example, peanut oil, liquid paraffin, or olive oil.
The pharmaceutical compositions may be in the form of a sterile injectable suspension. This suspension may be formulated according to known methods using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides, fatty acids (including oleic acid), naturally occurring vegetable oils like sesame oil, coconut oil, peanut oil, cottonseed oil, etc., or synthetic fatty vehicles like ethyl oleate or the like. Buffers, preservatives, antioxidants, and the like can be incorporated as required.
Invention compounds may also be administered in the form of suppositories for rectal administration of the drug. These compositions may be prepared by mixing the invention compounds with a suitable non-irritating excipient, such as cocoa butter, synthetic glyceride esters of polyethylene glycols, which are solid at ordinary temperatures, but liquefy and/or dissolve in the rectal cavity to release the drug.
Since individual subjects may present a wide variation in severity of symptoms and each drug has its unique therapeutic characteristics, the precise mode of administration and dosage employed for each subject is left to the discretion of the practitioner.
The compounds and pharmaceutical compositions described herein are useful as medicaments in mammals, including humans, for treatment of diseases and or alleviations of conditions which are responsive to treatment by antagonists of sphingosine-1-phosphate receptors. Thus, in further embodiments of the invention, there are provided methods for treating a disorder associated with modulation of sphingosine-1-phosphate receptors. Such methods can be performed, for example, by administering to a subject in need thereof a pharmaceutical composition containing a therapeutically effective amount of at least one invention compound. As used herein, the term “therapeutically effective amount” means the amount of the pharmaceutical composition that will elicit the biological or medical response of a subject in need thereof that is being sought by the researcher, veterinarian, medical doctor or other clinician. In some embodiments, the subject in need thereof is a mammal. In some embodiments, the mammal is human.
The following examples are intended only to illustrate the invention and should in no way be construed as limiting the invention.
EXAMPLES
Preparation of 4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 6)
A mixture of 4-bromobenzamide (2.42 g, 11.7 mmol) and chloral (2.2 mL, 22.6 mmol) was heated at 120° C. for 20 min. THF (˜2 mL) may be added to aid mixing. The mixture was cooled to room temperature and the mixture was evaporated and dried under vacuum for 18 hours. The intermediate product, 4-bromo-N-(2,2,2-trichloro-1-hydroxyethyl)benzamide, was sufficiently pure as to be used in subsequent steps without further purification.
A solution of 4-bromo-N-(2,2,2-trichloro-1-hydroxyethyl)benzamide (0.67 g, 1.93 mmol) in chloroform (15 mL) was treated with PCl 5 (0.42 g, 1.91 mmol). The mixture was heated to 50° C. for 30 minutes before cooling to room temperature and pouring into crushed ice. The organic layer was dried over MgSO 4 and filtered. The solution of 4-bromo-N-(1,2,2,2-tetrachloroethyl)benzamide was cooled to room temperature before addition of 4-chloroaniline (0.52 mL, 4.0 mmol), and the mixture was allowed to stir for 18 hours. The mixture was quenched with 2 M HCl and extracted with ether. The organic solution was dried over MgSO 4 , filtered, and concentrated onto silica gel. The material was purified on an MPLC with 7:3 CH 2 Cl 2 :hexanes to give 4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 6) as a solid. The product may be further purified by an appropriate recrystallization such as in ether.
1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.4 Hz, 2H), 7.59 (d, J=8.7 Hz, 2H), 7.19 (d, J=9.0 Hz, 2H), 6.77 (d, J=8.7 Hz, 2H), 6.53 (d, J=9.0 Hz, 1H), 6.33 (d, J=9.3 Hz, 1H).
The following compounds were prepared according to the general method set forth in Scheme A and as set forth above for Compound 6.
4-bromo-N-(2,2,2-trichloro-1-(p-tolylamino)ethyl)benzamide (Compound 7)
1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.7 Hz, 2H), 7.58 (d, J=8.7 Hz, 2H), 7.04 (d, J=8.4 Hz, 2H), 6.74 (d, J=8.4 Hz, 2H), 6.52 (d, J=9.3 Hz, 1H), 6.35 (d, J=9.0 Hz, 1H).
4-chloro-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 10)
1 H NMR (300 MHz, CDCl 3 ) δ 7.72 (d, J=8.7 Hz, 2H), 7.43 (d, J=8.7 Hz, 2H), 7.19 (d, J=8.7 Hz, 2H), 6.77 (d, J=8.7 Hz, 2H), 6.53 (d, J=9.3 Hz, 1H), 6.33 (d, J=9.6 Hz, 1H).
4-bromo-N-(2,2,2-tribromo-1-(4-chlorophenylamino)ethyl)benzamide (Compound 12)
1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.7 Hz, 2H), 7.58 (d, J=8.7 Hz, 2H), 7.04 (d, J=8.4 Hz, 2H), 6.74 (d, J=8.4 Hz, 2H), 6.52 (d, J=9.3 Hz, 1H), 6.35 (d, J=9.0 Hz, 1H).
6-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)nicotinamide (Compound 28)
1 H NMR (300 MHz, CD 3 OD) δ appears as rotamers 8.75 (d, J=2.4 Hz, 1H), 8.44 (brs, 1H) 8.15 (dd, J=8.4, 2.4 Hz, 1H), 7.42 (d, J=8.1 Hz, 1H), 7.16 (d, J=8.7 Hz, 2H), 6.75 (d, J=8.7 Hz, 2H), 6.34 (d, J=9.6 Hz, 1H).
5-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)picolinamide (Compound 29)
1 H NMR (300 MHz, CDCl 3 ) δ 8.62-8.61 (m, 1H), 8.50 (d, J=9.9 Hz, 1H), 8.12 (dd, J=8.4, 0.6 Hz, 1H), 8.04-8.00 (m, 1H), 7.18 (d, J=9.0 Hz, 2H), 6.78 (d, J=8.0 Hz, 2H), 6.28 (t, J=9.6 Hz, 1H), 4.55 (d, J=9.6 Hz, 1H).
(+)-4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 30)
This was obtained from chiral HPLC separation (Chiralpak IA 40% MeOH, 0.1% DEA/CO 2 at 100 barr) of Compound 6 above.
[α]=+96.1° (c 1.08, CHCl 3 )
1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.4 Hz, 2H), 7.59 (d, J=8.7 Hz, 2H), 7.19 (d, J=9.0 Hz, 2H), 6.77 (d, J=8.7 Hz, 2H), 6.53 (d, J=9.0 Hz, 1H), 6.33 (d, J=9.3 Hz, 1H).
(−)-4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 31)
This was obtained from chiral HPLC separation (Chiralpak IA 40% MeOH, 0.1% DEA/CO 2 at 100 barr) of Compound 6 above.
[α]=−99.2° (c 1.12, CHCl 3 )\
1 H NMR (300 MHz, CDCl 3 ) δ 1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.4 Hz, 2H), 7.59 (d, J=8.7 Hz, 2H), 7.19 (d, J=9.0 Hz, 2H), 6.77 (d, J=8.7 Hz, 2H), 6.53 (d, J=9.0 Hz, 1H), 6.33 (d, J=9.3 Hz, 1H).
3,4-difluoro-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)benzamide (Compound 32)
1 H NMR (300 MHz, CDCl 3 ) δ 7.68-7.62 (m, 1H), 7.55-7.50 (m, 1H), 7.26-7.17 (m, 3H), 6.76 (d, J=8.7 Hz, 2H), 6.53 (d, J=9.3 Hz, 1H), 6.31 (t, J=9.0 Hz, 1H), 4.51 (d, J=8.4 Hz, 1H).
(−)-5-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)picolinamide (Compound 34)
Compound 34 has identical NMR as Compound 29, but has an (−) optical rotation. Compound 34 was obtained from chiral HPLC separation (Chiralpak IA 30% MeOH, CO 2 at 100 barr) of Compound 29 above: and collect the first eluting peak (−) enantiomer: [α]=−121° (c 0.69 in CHCl 3 ). 1 H NMR (300 MHz, CDCl 3 ) δ 8.62-8.61 (m, 1H), 8.50 (d, J=9.9 Hz, 1H), 8.12 (dd, J=8.4, 0.6 Hz, 1H), 8.04-8.00 (m, 1H), 7.18 (d, J=9.0 Hz, 2H), 6.78 (d, J=8.0 Hz, 2H), 6.28 (t, J=9.6 Hz, 1H), 4.55 (d, J=9.6 Hz, 1H).
5-Bromo-N-(1-(4-chlorophenylamino)-2,2,2-trifluoroethyl)picolinamide (Compound 35)
1 H NMR (300 MHz, CDCl 3 ) δ=8.55 (d, J=2.4 Hz, 1H), 8.28 (d, J=9.3 Hz, 1H), 8.09 (d, J=8.1 Hz, 1H), 7.99 (dd, J=2.4, 8.7 Hz, 1H), 7.14 (d, J=8.7 Hz, 2H), 6.71 (d, J=9.0 Hz, 2H), 6.25-6.12 (m, 1H), 4.47 (d, J=10.2 Hz, 1H).
5-Chloro-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)picolinamide (Compound 36)
1 H NMR (300 MHz, CDCl 3 ) δ=8.51-8.47 (m, 2H), 8.18 (d, J=9.3 hz, 1H), 7.88-7.84 (m, 1H), 7.17 (d, J=8.7 Hz, 2H), 6.77 (d, J=8.4 Hz, 2H), 6.28 (t, J=10.2 Hz, 1H), 4.54 (d, J=9.6 Hz, 1H).
5-Bromo-N-(2-chloro-1-(4-chlorophenylamino)-2,2-difluoroethyl)picolinamide (Compound 37)
1 H NMR (300 MHz, CDCl 3 ) δ=8.53 (d, J=2.1 Hz, 1H), 8.35 (d, J=9.6 Hz, 1H), 8.08 (d, J=8.7 Hz, 1H), 7.99-7.95 (m, 1H), 7.14-7.11 (m, 2H), 6.73-6.70 (m, 2H), 6.26-6.16 (9m, 1H), 4.55 (d, J=10.2 Hz, 1H).
4-bromo-N-[1-(4-chlorophenylamino)-2,2,2-trifluoro-ethyl]-benzamide (Compound 13)
was prepared by use of 2,2,-trifluoro-1-methoxy-ethanol in place of chloral in the general method set forth above with the following procedural changes: A mixture of 4-bromobenzamide (0.78 g, 3.9 mmol) and 2,2,2-trifluoro-1-methoxy-ethanol (0.51 mL, 4.3 mmol) was heated at 100° C. for 18 hours. The mixture was evaporated and the residue was diluted with chloroform and concentrated onto silica gel. The product was purified on a SiO 2 MPLC column with 1% MeOH:CH 2 Cl 2 to yield the intermediate 4-bromo-N-(2,2,2-trifluoro-1-hydroxyethyl)benzamide, which was used in the general method set forth above to prepare Compound 13.
1 H NMR (300 MHz, CDCl 3 ) δ 7.64-7.56 (m, 2H), 7.18 (d, J=9.0 Hz, 2H), 6.70 (d, J=8.7 Hz, 2H), 6.33 (d, J=9.3 Hz, 1H), 6.26-6.18 (m, 1H).
4-bromo-N-[2,2,2-trichloro-1-(4-chloro-3-fluoro-phenylamino)-ethyl]-benzamide (Compound 14)
1 H NMR (300 MHz, CDCl 3 ) δ 7.65 (d, J=8.7 Hz, 2H), 7.60 (d, J=9.3 Hz, 2H), 7.21 (t, J=8.1 Hz, 1H), 6.67 (dd, J=11.1, 3.0 Hz, 1H), 6.59-6.55 (m, 1H), 6.30 (d, J=9.0 Hz, 1H), 4.59 (brs, 1H).
Furan-2-carboxylic acid (2,2,2-trichloro-1-p-tolylamino-ethyl)-amide (Compound 15)
1 H NMR (300 MHz, CDCl 3 ) δ 7.44 (dd, J=0.9, 1.8 Hz, 1H), 7.22 (dd, J=0.9, 3.6 Hz, 1H), 7.04 (d, J=7.8 Hz, 2H), 6.85 (d, J=9.3 Hz, 1H), 6.74 (d, J=8.4 Hz, 2H), 6.52 (dd, J=1.8, 3.6 Hz, 1H), 6.32 (t, J=9.6 Hz, 1H), 4.43 (d, J=9.3 Hz, 1H), 2.24 (s, 3H).
Furan-2-carboxylic acid (2,2,2-trichloro-1-(4-chloro-3-fluoro-phenylamino)-ethyl)-amide (Compound 16)
1 H NMR (300 MHz, CDCl 3 ) δ 7.46 (dd, J=0.6, 1.8 Hz, 1H), 7.24 (dd, J=0.6, 3.3 Hz, 1H), 7.19 (t, J=8.7 Hz, 1H), 6.90 (d, J=9.3 Hz, 1H), 6.66 (dd, J=3.0, 11.1 Hz, 1H), 6.59-6.53 (m, 2H), 6.26 (d, J=9.3 Hz, 1H), 4.66 (brs, 1H).
5-bromo-furan-2-carboxylic acid (2,2,2-trichloro-1-(4-chloro-phenylamino)-ethyl)-amide (Compound 17)
1 H NMR (300 MHz, CDCl 3 ) δ 7.20-7.17 (m, 3H), 6.76-6.71 (m, 3H), 6.48 (d, J=3.3 Hz, 1H), 6.27 (d, J=9.3 Hz, 1H).
N-{2,2,2-trichloro-1-[(4-fluoro-3-methylphenyl)amino]ethyl}-2-furamide (Compound 18)
1 H NMR (500 MHz, CDCl 3 ) δ 7.48 (s, 1H), 7.24 (d, J=3.5 Hz, 1H), 6.88 (t, J=8.5 Hz, 1H), 6.80 (d, J=9.5 Hz, 1H), 6.66-6.54 (series of m, 3H), 6.25 (t, J=9.5 Hz, 1H), 4.35 (d, J=9.5 Hz, 1H), 2.20 (s, 3H).
N-{2,2,2-trichloro-1-[(2-fluoro-4-methylphenyl)amino]ethyl}-2-furamide (Compound 19)
1 H NMR (500 MHz, CDCl 3 ) δ 7.48 (s, 1H), 7.24 (d, J=3.5 Hz, 1H), 6.93-6.84 (series of m, 3H), 6.54 (dd, J=2.0, 1.5 Hz, 1H), 6.31 (t, J=9.5 Hz, 1H), 4.66 (dd, J=6.5, 2.5 Hz, 1H), 2.25 (s, 3H).
N-{2,2,2-trichloro-1-[(2-fluorophenyl)amino]ethyl}-2-furamide (Compound 20)
1 H NMR (500 MHz, CDCl 3 ) δ 7.48 (dd, J=1.0, 0.5 Hz, 1H), 7.25 (d, J=3.5 Hz, 1H), 7.05-7.01 (m, 3H), 6.86 (d, J=10.0 Hz, 1H), 6.81-6.78 (m, 1H), 6.55-6.54 (m 1H), 6.36 (t, J=9.5 Hz, 1H), 4.80 (dd, J=2.5, 6.5 Hz, 1H).
N-{2,2,2-trichloro-1-[(4-fluoro-2-methylphenyl)amino]ethyl}-2-furamide (Compound 21)
1 H NMR (500 MHz, CDCl 3 ) δ 7.48 (s, 1H), 7.25 (dd, J=3.0, 1.0 Hz, 1H), 6.85-6.81 (m, 2H), 6.55 (dd, J=2.0, 1.9 Hz, 1H), 6.28 (d, J=9.0 Hz, 1H), 4.28 (brs, 1H), 2.23 (s, 3H).
N-{2,2,2-trichloro-1-[(2,6-dimethylphenyl)amino]ethyl}-2-furamide (Compound 22)
1 H NMR (500 MHz, CDCl 3 ) δ 7.47 (d, J=1.0 Hz, 1H), 7.11 (d, J=7.0 Hz, 1H), 6.98 (d, J=7.5 Hz, 1H), 6.86 (t, J=7.5 Hz, 1H), 6.76 (d, J=9.5 Hz, 1H), 6.50 (dd, J=1.5, 4.0 Hz, 1H), 6.17 (t, J=10.5 Hz, 1H), 4.09 (d, J=10.5 Hz, 1H), 2.41 (s, 6H)
N-{2,2,2-trichloro-1-[(4-chlorophenyl)amino]ethyl}-2-furamide (Compound 23)
1 H NMR (500 MHz, CDCl 3 ) δ 7.40 (t, J=1.0 Hz, 1H), 7.17 (dd, J=6.5, 0.5 Hz, 1H), 7.11 (dd, J=4.5, 2.0 Hz, 1H), 6.22 (t, J=9.0 Hz 1H), 4.42 (d, J=9.0 Hz, 1H).
N-{2,2,2-trichloro-1-[(3-fluorophenyl)amino]ethyl}-2-furamide (Compound 24)
1 H NMR (500 MHz, CDCl 3 ) δ 7.58-7.56 (m, 3H), 7.45 (s, 1H), 7.20-7.16 (m, 1H), 6.84 (d, J=9.5 Hz, 1H), 6.65-6.51 (series of m, 2H), 6.33 (t, J=9.5 Hz, 1H), 4.60 (d, J=6.5 Hz, 1H).
N-{2,2,2-trichloro-1-[(4-fluorophenyl)amino]ethyl}-2-furamide (Compound 27)
1 H NMR (300 MHz, CDCl 3 ) δ 7.45 (dd, J=0.6, 1.5 Hz, 1H), 7.22 (dd, J=0.6, 3.6 Hz 1H), 6.95-6.85 (m, 3H), 6.80-6.75 (m, 2H), 6.52 (dd, J=1.8, 3.3 Hz, 1H), 6.25 (d, J=9.9 Hz, 1H), 4.4 (brs, 1H).
4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)furan-2-carboxamide (Compound 33)
was prepared in accordance with reported methods: see Ulrich, H. et al J Org. Chem., 33, 1968, 2887. A solution of 4-bromo-N-(2,2,2-trichloro-1-hydroxyethyl)furan-2-carboxamide (preparation as for 6 above) (0.566 g, 1.67 mmol), 1-chloro-4-isocyanato-benzene (0.264 g, 1.68 mmol) and triethylamine (2 drops) in benzene (4 mL) was heated at 95° C. for 1.5 h. The mixture was evaporated under reduced pressure. The residue was solvated with chloroform and concentrated onto silica gel. Chromatographic purification on an auto-column with 30% dichloromethane in hexanes gave 4-bromo-N-(2,2,2-trichloro-1-(4-chlorophenylamino)ethyl)furan-2-carboxamide (Compound 33) as a white solid; 422 mg (57%).
1 H NMR (300 MHz, CDCl 3 ) δ 7.46 (d, J=0.9 Hz, 1H), 7.23 (d, J=0.9 Hz, 1H), 7.18 (d, J=8.7 Hz, 2H), 6.80 (d, J=9.6 Hz, 1H), 6.74 (d, J=8.7 Hz, 2H), 6.26 (t, J=9.6 Hz, 1H), 4.52 (d, J=9.3 Hz, 1H).
While this invention has been described with respect to these specific examples, it is understood that other modifications and variations are possible without departing from the spirit of the invention. | This invention provides compounds as shown below, in which either all of Z 1-6 are carbon or one of Z 1-6 is nitrogen and the rest are carbon, and in which other substituents are defined herein, which are sphingosine-1-phosphate antagonists. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a door lock associated with a motor home having an alarm circuit for connection to the electrical system of the vehicle to alert the operator prior to movement of the vehicle that the lock is not secured, and more particularly to a motor home refrigerator door lock.
2. Description of the Prior Art
Modern motor homes, camping trailers and other recreational vehicles have refrigerators and freezers installed therein. Due to the close quarters in such vehicles, it is common practice to omit from the refrigerator or freezer the usual door handle and positive lock that might be found on a unit designed for the home. Instead, it is common to provide simple friction or magnetic locks to allow easy access to the refrigerator contents while the motor home is parked, and a locking device that requires an overt manual operation to secure the doors prior to driving the vehicle.
An inherent problem in this arrangement is that the user neglects to apply the manual lock to the refrigerator or freezer door prior to start-up and movement of the vehicle. Thus, it is highly probable that acceleration and turning of the vehicle will cause the doors to swing open with the resulting danger of the contents spilling out onto the floor of the vehicle. Of course, such spillage can, at worst, result in injury to occupants, and at best, waste food and stain carpets.
While door lock alarms are old in the art, no known prior art has approached or solved this problem resulting from the widespread use of recreational vehicles, motor homes, and the like by providing means of warning the operator of such unsafe condition.
SUMMARY OF THE PRESENT INVENTION
My door lock for refrigerators, freezers, and the like includes alarm means to be interconnected with the vehicle electrical system so that operation of the vehicle ignition switch will cause an alarm, thereby alerting the operator that the doors are not locked for driving. Basically, the invention is a simple, low-cost, easily installed manual lock for refrigerator and freezer doors consisting of a locking handle operatively connected with a set of electrical contacts. The contacts are open when the lock is in the correct locked condition and are closed when the lock is in the unlocked condition. Wire leads from the contacts are connected in series with a warning light and buzzer combination, and the accessories contacts of the vehicle ignition switch. Thus, the alarm is initiated when the ignition switch is turned on and the manual lock is unlocked.
Therefore, it is an object of my invention to provide a lock and associated warning signal means for refrigerators and freezers mounted in recreational vehicles, motor homes, and the like which will produce a signal to the vehicle driver when starting that the refrigerator and freezer doors are not securely locked.
It is another object of my invention to provide a manual refrigerator lock that is compact and will not project into the aisles of a recreational vehicle in which it is installed.
It is still another object of my invention to provide a refrigerator door lock for motor home type refrigerators having associated electrical contacts for operating an alarm when the vehicle is started when the door lock is not secure.
It is yet another object of my invention to provide a manually operated refrigerator door lock having a built-in alarm circuit that can be easily installed on an existing motor home refrigerator or the like.
It is a further object of my invention to provide a simple, low-cost manually operated refrigerator door lock having a built-in alarm circuit.
Additional objects and advantages of my invention will become apparent from the following detailed descriptions and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the lock portion of my refrigerator door lock with integral alarm,
FIG. 2 is a cross sectional view of the lock portion of FIG. 1 through section 2-2' of that figure,
FIG. 3 is a bottom view of the body of the lock portion of FIG. 1 with the bottom plate removed to expose the switch contacts, recesses, and wire grooves,
FIG. 4 is a perspective view of the rotable switch contacts seen in bottom view in FIG. 3,
FIG. 5 is a schematic diagram of the alarm circuit of my refrigerator door lock connected to the ignition switch accessory contacts of a vehicle,
FIG. 6 is a fragmentary front view of a refrigerator-freezer having the lock portion of my invention installed thereon and shown in the unlocked condition, with doors open and not shown,
FIG. 7 is a fragmentary front view of the refrigerator-freezer of FIG. 6 in which the upper and lower doors are closed and locked by my novel manual refrigerator door lock,
FIG. 8 is a fragmentary side view of the refrigerator-freezer of FIG. 7 showing how my manual refrigerator door lock holds the upper and lower doors tightly shut against the door gaskets,
FIG. 9 shows a preferred means for permitting adjustment of the length of the lock handle of FIG. 1,
FIG. 10 is a perspective view of an alternative embodiment of my alarm lock device installed on a refrigerator,
FIG. 11 is a perspective view of the lock shaft assembly of the lock of FIG. 10, showing details of the rotable switch contact,
FIG. 11a is a fragmentary view of the rotable switch contact and the lock body, showing details of the stationary switch contacts,
FIG. 12 is a bottom view of the lock handle of the lock of FIG. 10,
FIG. 13 is a front view of the lock handle,
FIG. 14 is a side view of the lock handle,
FIG. 15 is a perspective view of an adjustment guide for adjusting the length of the lock shaft,
FIG. 16 is a fragmentary view of a refrigerator showing the guide being set, and
FIG. 17 is a perspective view of the set guide of FIG. 16 in use to adjust the lock shaft.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of my refrigerator door lock for refrigerators and freezers installed in motor homes and the like is shown in perspective view in FIG. 1. The lock element comprises a body 30, a bottom plate 31, a lock handle 20 and a lock shaft 21. The base of body 30 is generally T shaped to fit on a mullion between refrigerator/freezer doors as illustrated in FIGS. 6, 7 and 8. Body 30 may be made from any suitable material although I prefer a plastic material such as Lexan, nylon or the like. A shaft bearing portion 32 of body 30 carries lock shaft 21, best seen in the sectional view of FIG. 2. Shaft 21 may be of steel or other metal and has its outer end threaded to receive locking nut 22 and the hub 20a of lock handle 20. The position of handle 20 on shaft 21 can be adjusted as will be explained in detail below. Lock handle 20 forms a T shape with lock shaft 21 having an outward taper on the underside of handle 20 from the hub 20a to the outer ends 20b.
Turning to the cross sectional views of FIG. 2 and FIG. 3, details of switch 50 are shown. A cylindrical shaft bearing portion of body 30 is shown with concentric opening 37 which serves as the bearing for shaft 21. At the bottom end of opening 37 is a cylindrical recess 36 and concentric with opening 37. The lower end of shaft 21 has a cylinder 23 insulating materials attached by means of pin 24 passing through cylinder 23 and shaft 21. The preferred construction of cylinder 23 is shown in the perspective view of FIG. 4. Two arcuate contact strips 25 of spring brass, phosphor bronze or similar material are disposed in slots 26 in cylinder 23. As may be noted in FIG. 3, each strip 25 covers an angle of about 165° and the strips 25 are oppositely disposed. Strips 25 serve as conductive contacts to bridge across two contact points 34 with the slight springiness of strips 35 providing positive contact with points 34. Contact points 34 may be formed by the heads of two brass rivets 34a pressed into the wall of recess 36 and extending into groove 39 in body 30. A pair of wires 35 are electrically connected to the rivets 34a and dressed out from the base in the channel formed by groove 39 and bottom plate 31. For some installations, wire leads 35 may be dressed through opening 39a in base plate 31 as shown in phantom view as leads 35a.
As may now be understood, rotation of lock shaft 21 will cause one of contact strips 25 to bridge across the two contact points 34 of switch 50, thereby closing an electrical circuit. When shaft 21 is rotated to place either of the peripheral segments of cylinder 23 not covered by contact strips 25 adjacent to contact points 34, such electrical circuit will be in an open or nonconductive condition. The provision of two oppositely disposed contact strips and two oppositely disposed non-contact areas allows the user to rotate lock handle 20 in either direction without negating the alarm action.
The connections of the switch 50 thus formed by contact strips 25 and contact points 34 with the other elements of my invention to form an alarm is shown schematically in FIG. 5. Switch 50 is connected in series with lamp 11 and buzzer 12 in parallel connection, and with ignition switch contacts 15 to the terminal of vehicle battery 14, with the vehicle ground furnishing the return path between battery 14 and switch 50. Switch contacts 15 are the usual "accessory" contacts of ignition switch 13 and are not to be understood as part of my invention. When switch 50 is in the open position shown in detail A, the ignition switch 13 can be turned on without causing lamp 11 and buzzer 12 to be operated. However, if switch 50 is in closed position as shown in detail B, indicative of an unlocked condition of the refrigerator doors, then in accordance with my invention, lamp 11 will light and buzzer 12 will sound, alerting the driver of the unsafe condition. Lamp 11 may be any suitable lamp preferably mounted in a conspicuous spot on the vehicle instrument panel, and buzzer 12 may be any type of audible warning device.
Turning now to FIGS. 6, 7 and 8, a typical installation of my novel refrigerator lock and alarm is shown. The refrigerator 40 includes an upper compartment 43 and a lower compartment 44 separated by mullion 60. In FIG. 6, a fragmentary front view of refrigerator 40 is given with the doors to compartments 43 and 44 assumed open and not shown. Body 30 of my door lock is mounted by mounting screws 33 to center the handle 20 on mullion 60. Leads 35 are dressed around the left corner of refrigerator 40 and rearwardly along left side 41. A plastic covering 36 may be installed along side 41 to cover leads 35 for protection thereof and for improving the appearance of the installation.
Handle 20 in FIG. 6 is shown parallel with mullion 60 allowing the doors (not shown) to be freely opened and closed. In the fragmentary front view of refrigerator 40 of FIG. 7, upper door 45 and lower door 46 are shown closed with handle 20 rotated 90° from the position of FIG. 6, with the underside of handle 20 contacting the lower edge of upper door 45 and the upper edge of lower door 46, thereby securing doors 45 and 46 from opening.
The fragmentary side view of refrigerator 40 to be seen in FIG. 8 illustrates more specifically the locking action of handle 20. As doors 45 and 46 are closed, gaskets 47 of a compressible material bear on the door mullions. The tapered configuration of handle 20 allows the tip ends 20b of the handle 20 as it is rotated to slide over the door edges with gaskets 47 uncompressed, and as handle 20 continues to rotate, causes compression of gaskets 47. When handle 20 is vertical as shown, considerable tension from the compressed gaskets 47 holds the doors 45 and 46 tightly locked in accordance with my invention.
Handle 20 is oriented on lock shaft 21 so that switch 50 is in the open condition when in the locked position of FIG. 7 and in the closed condition in the unlocked position of the handle 20 in FIG. 6.
As may be understood, to make my refrigerator door lock adaptable to various models and types of refrigerators, the length of shaft 21 with respect to handle 20 must be adjustable. FIG. 9 shows a preferred arrangement for this purpose. Shaft 21 is threaded at its outer end and has a flat surface 54 provided on one side. The hub 20a of handle 20 is threaded to fit the threads of shaft 21. A threaded metal bushing 52 is disposed in the hub 20a of handle 20 to accept set screw 53. To adjust handle 20, locking nut 22 is loosened and set screw 53 is backed out allowing handle 20 to be screwed up or down on the threaded end of shaft 21. When the adjustment is completed so as to obtain the desired locking tension on the refrigerator doors, a minor adjustment is made to bring bushing 52 adjacent the flat 54 of shaft 21 and set screw 53 tightened against flat 54. Locking nut 22 is then tightened against the hub 20a of handle 20.
As previously discussed, cylinder 23 is secured to shaft 21 by pin 24. It may now be recognized that the orientation of cylinder 23 on shaft 21 with respect to flat 54 is selected such that switch 50 is in the open condition with handle 20 in the locked position on refrigerator 40 as shown in FIG. 7. Lock handle 20 may be rotated 180° and still perform its locking function. It is for this reason that I have provided two contact strips 25 on cylinder 23 so that my alarm circuit is operative for either position of handle 20.
While many materials are suitable for the construction of lock handle 20, I prefer to use a strong plastic such as Lexan or nylon. The bottom plate 31 is preferably formed from an insulating material such as plastic, bakelite or the like.
DETAILED DESCRIPTION OF AN ALTERNATIVE EMBODIMENT
The preferred embodiment of my invention described hereinabove is applicable to many popular types of refrigerator-freezers used in motor homes. However, there are other designs which have very closely spaced doors and there is not sufficient space to mount the alarm lock device 5 between the doors as shown in FIG. 6. I will now describe an alternative embodiment of my novel alarm lock that is suitable for attaching to refrigerators of such design.
Turning to FIG. 10, a perspective view of this version 60 of my invention is shown mounted on a refrigerator-freezer 100 having an upper door 102 and a lower door 103. For purposes of clarity of viewing the alarm lock element 60, the viewpoint is as if the refrigerator 100 were tipped on its back, which is not to be considered the normal operating position. Alarm lock element 60 consists of a body portion 61, bottom plate 62, lock shaft 70, and a lock handle 80. The body 61 differs from the previously-described body 30 of FIG. 1 only in its shape, being of a generally rectangular base portion which may be 1 inch by 21/2 inches and having a shaft bearing portion 64 corresponding to shaft bearing portion 32 of FIG. 1. A switch assembly, not seen in FIG. 10 is contained within body 61 and operated by shaft 70 in a similar fashion as switch 50 of the preferred embodiment, and explained in more detail below.
Lock shaft 70, as shown in FIG. 11, includes a cylinder 73 of insulating material attached at its inner end. An arcuate contact strip 74 formed from spring brass, phosphor bronze or the like, covers approximately 315° of the periphery of cylinder 73 and may be mounted in suitable slots cut into the peripheral surface so as to form a contact surface biased in a radial direction. An approximate 45° non-conducting surface 72 is thus formed on the periphery of cylinder 73 between the ends of strip 74. A flat surface 71 is milled on the outer end of shaft 70 and aligned with the non-conducting surface 72. Hole 75 is drilled near the outer end through flat surface 71 for attachment of the lock handle 80. The manner in which contact strip 74 is utilized may be seen with reference to FIG. 11a which shows a section of body 61 through the switch area. Rivet-like brass contacts 67 are disposed in cylindrical recess 68 which is concentric with cylinder 73. When the shaft 70 is in the position shown no contact is made across contacts 67. However, contact strip 74 bridges contacts 67 when shaft 70 is rotated slightly less than 45°. Leads 66 attached to contacts 67 serve to connect the switch assembly to the vehicle and alarm circuit in the same manner as previously described with reference to the preferred embodiment.
The lock handle 80 is shown in detail in FIGS. 12, 13 and 14 with FIG. 12 being a bottom view of handle 80. An opening 88 is formed corresponding to the size of shaft 70 and having a flat surface therein to form a snug fit in shaft 70. A pin 82 is pressed into the side of handle 80 through hole 75 in shaft 70, securely locking the handle 80 to shaft 70 in its required relationship. The bottom view of handle 80 discloses a semi-circular portion 84 that is seen also in FIG. 10 whose underside 85, 86 serves to contact the outer surfaces of the refrigerator doors 102 and 103. As may now be seen, portion 84 serves to maintain doors 102 and 103 securely locked in when in position 84a of FIG. 10. When the handle 80 is rotated 180° to position 84b, shown in phantom view in FIG. 10, the doors 102 and 103 will be free to open.
As shown in FIG. 12, 13, and 14, the under surface of portion 84 is slightly relieved or tapered as at 85 to allow the underside of portion 84 to slide over the door edges and to allow flat area 86 to contact the doors and compress gaskets 104 ensuring a tight friction lock.
FIG. 13 is a view in the direction A of FIG. 12, and FIG. 14 is a view in the direction B of FIG. 13, each Figure revealing additional details of handle 80 and showing more clearly the desired tapered areas 85. Also shown is hand grip 81 which projects outward and normal to portion 84 and may be molded to provide a convenient gripping surface to the user.
It may be recognized that the locking action of lock handle 80 depends on the length of shaft 70 being selected to provide sufficient compression of the door gaskets 104 when in the locked position. Since all refrigerators do not have the same thickness doors, I have provided a convenient method of matching my lock element 60 to a particular refrigerator at time of installation of the lock element. At time of manufacture, shaft 70 is made in a length longer than required for the greatest door thickness expected, and hole 75 is not drilled. The length of shaft 70 is then determined at the time of installation, excess length cut off, and hole 75 drilled in the correct position. To allow the installer to make this determination, I provide an expendable adjustment guide 90 shown in FIG. 15 comprising a strip of light metal having a right angle bend 91 at one end. The bent end 91 has opening 92 which will fit snugly over the flat-sided outer end of shaft 70. A drill guide hole 93 is disposed just above bent end 91. Above hole 93, the strip is bent in a step shape 95 leaving a guage end 94.
FIG. 16 illustrates how guide 90 is set for a particular refrigerator 100 seen in top view. End 91 is held against outer mullion 101 of refrigerator 100 and guage end 94 is firmly held against the outer edge of door 102. The free end of guage end 94 is bent as shown by the arrow at right angles at point C to conform to the face of door 102. As may be seen, the distance from bent guage end 94 to end 91 is then a measure of the door 102 thickness plus the uncompressed gasket 104 thickness. At this point, guide 90 is temporarily installed on the body and shaft assembly of lock element 60.
As shown in FIG, 17, the set guide 90 is placed over shaft 70 through its opening 92. Bent guage end 94 is next held firmly on the flat surface of body 61 with step shape 95 clearing shaft bearing portion 64. Drill guide hole 93 is against the flat surface 71 of shaft 70 and provides a guide for drilling hole 75 as at D in FIG. 17. After drilling hole 75, shaft 70 is cut off at point E, using end 91 as a guide. After adjustment is complete, guide 90 may be discarded. The hole 93 position has been selected so that installation of handle 80 and pin 82 on shaft 70 will result in the correct compression of gaskets 104 when handle 80 is in the locked position.
As illustrated in FIG. 10, alarm lock element 60 can be mounted on the outside mullion 101 of a refrigerator or the like. However, in some manufacturer's models, the door edges are flush with the side of the box when closed. Thus, there is no convenient mounting surface. In such cases, I prefer to use a simple angle bracket with one face matching in size the base 61 of the lock element 60. The base 61 is bolted to the bracket with screws 63 and the bracket attached to the side of the box so as to bring the lock handle portion 84 in the proper position relative to the door faces to perform its locking function.
APPLICATION
Having described a preferred embodiment and an alternative embodiment of my novel refrigerator door lock with alarm circuit in detail, the application of the devices will be explained. As previously discussed, the primary use foreseen is in mobile homes, camping trailers, recreational vehicles and other vehicles in which there is a danger of spillage of the contents of unlocked storage elements, with application to refrigerators and freezers the most common. The lock elements can be added to most existing refrigerators/freezers and can be modified to fit other equipment such as pantries, utensil storage cabinets, filing cabinets and the like. It is, of course, eminently practical to install a version of my alarm lock at time of manufacture of equipment to which it may be applied.
After physical installation of the lock element on a refrigerator or other cabinet, one of the contact switch leads is grounded to the vehicle chassis and the other lead is connected in series with the warning device and the accessory contact on the vehicle ignition switch, thereby providing warning to the driver when an attempt is made to start the vehicle and the lock is not secured.
While I have described two embodiments of my invention, it is obvious that many variations in construction will occur to those skilled in the art. For example, the contact switch can utilize many types of electrical contacts well-known in the art in place of the low-cost preferred contacts. Similarly, a preassembled switch of the snap-action type can be used with a cam arrangement on the rotable handle serving to operate the switch. Therefore, I consider that such modifications fall within the spirit and scope of my invention. | A manual positive locking device for doors of refrigerators, freezers and the like that do not have positive door locks such as typically used in motor homes, the locking device having an integral switch connected to an electrical alarm and adapted to be connected to the electrical system of the vehicle such that attempting to start the vehicle with the locking device in the unlocked condition will alert the operator of the unsecured condition. A rotatable T-shaped handle is provided that can be turned to a position that holds refrigerator doors in a tightly closed condition and in such position opens the contacts of the integral switch. The handle can be turned to a position clear of the doors and in such position closes the contacts of the integral switch and thus enables the alarm circuit for initiation when the vehicle ignition switch is turned on. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a power-vented water heater. The power venting is provided by a blower which induces a draft for the flue gases generated by the water heater. The heater utilizes a direct through-the-wall vent design thereby obviating the need for a chimney. The heater also utilizes a flexible flue gas exhaust line providing the advantage of installation flexibility.
DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 4,262,608 to Jackson discloses a water heater having a draft hood and a flue pipe leading to an air manifold. This patent further discloses a blower positioned immediately downstream from the manifold. The blower has a dual function, namely to force the exhaust gases out through the exhaust pipe and simultaneously bring in fresh outside air through an intake pipe. This type of system is generally referred to as a "balanced flue" system.
U.S. Pat. No. 4,424,792 to Shimek et al discloses a wood burning furnace utilizing a direct vent design. The direct vent utilizes an induced draft blower installed on the exterior of the wall which operates to draw flue gases through the flue pipe. This patent further discloses a pivoting cap at the vent outlet.
U.S. Pat. No. 4,424,792 is directed primarily to a device for cooling the hot flue gases before they pass through the exterior wall by mixing them with cool outside air just before venting.
Other prior art patents include U.S. Pat. Nos. 3,601,099; 1,859,745; 3,759,230; 2,563,817; 4,357,909; 1,935,919; 1,643,859; 1,713,442; 1,826,748; 2,348,950; 3,280,774; 4,303,042; 3,492,972; 4,487,137; Re 31,256; 4,254,759; 3,782,303.
The water heaters of the prior art have typically relied upon the natural draft of the hot flue gases, rising through the flue pipe(s) of a water heater and being vented into a chimney. Because these gases were warmer than the surrounding air, they tended to r:aturally rise. However, with this type of design, the positioning of the water tank was somewhat limited since for practical reasons it had to be placed close to the chimney. Thus, it is an object of the present invention to provide a water heater which need not be vented into a chimney, thereby providing greater installation flexibility.
It is another object of the present invention to provide a water heater venting design which needs no chimney. This is important from several cost reduction standpoints. First, in new house construction, homes may be constructed without a chimney, thereby significantly lowering the cost of a new home. Secondly, during the so called "gas moratorium" of the 1950's and 1960's, many houses were built for all-electric heating, and therefore have no chimney. Now that natural gas has become comparatively much less expensive, there is a desire by many "all-electric" home owners to convert to natural gas heating. Thus, it is an important object of the present invention to provide a water heater flue gas venting design adaptable to conversions from all electric heating.
It is a further object of the present invention to provide a direct through-the-wall vent design adaptable to high velocity outside winds.
It is another important object of the present invention to provide a flexible connector pipe between the water heater and the direct vent which is air tight, flexible, and which operates at a lower temperature thereby reducing the risk of burn injuries, and obviating condensation problems.
These and other important objects of the present invention will become readily apparent from the description appearing hereinafter.
SUMMARY OF THE INVENTION
A direct power vented water heater having a collection chamber positioned above the water tank, the collection chamber being in fluid communication with an exhaust blower and a flue gas exhaust line, is provided. The blower conveys the flue gases through the exhaust line to a direct through-the-wall vent. Water heater control means are provided for sensing the temperature of the water in the tank and controlling the amount of fuel supplied to the burner in response thereto. The control means activates the exhaust blower when the fuel is being supplied to the burner but deactivates the exhaust blower when the fuel supply to the burner is cut. The control means also interrupts the supply of fuel to the burner in the event that either a total or partial blockage of the flue gas exhaust occurs.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view, shown partly in section, of a water heater illustrating one embodiment of the present invention.
FIG. 2 is a side view, shown partly in section, of a water heater illustrating a second embodiment of the present invention.
FIG. 3 is a side view, shown partly in section, of a water heater illustrating a third "balanced flue" embodiment of the present invention.
FIG. 4 is a side view, shown partly in section, of one baffled flue pipe design with may be utilized with certain embodiments of the present invention.
FIG. 5 is a sectional view of the baffled flue pipe illustrated in FIG. 4 taken along line V--V.
FIG. 6 is a side sectional view of a direct through-the-wall vent according to one embodiment of the present invention.
FIG. 7 comprises two schematic wiring diagrams of one embodiment of the burner and blower control apparatus utilized in the present invention.
FIG. 8 is a side view, shown partly in section, of an alternate flue pipe, collector box and blower assembly which may be used in place of the assembly illustrated in FIG. 2.
FIG. 9 is a side view, shown partly in section, of a removable flue pipe baffle which may be used in certain embodiments of the present invention.
Although specific forms of apparatus embodying the invention have been selected for illustration in the drawings, and although specific terminology will be resorted to in describing those forms in the specification which follows, their use is not intended to define or to limit the scope of the invention, which is defined in the appended claims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings wherein like reference numerals refer to the same features in the several drawings, and especially referring to FIG. 1, there is shown a water heater 10. Heater 10 comprises a water tank 11 having a tank head 12 and a tank bottom 13. Extending vertically between tank head 12 and bottom 13 and passing through the interior of tank 11 is flue pipe 17 having internal baffling 18.
An alternate baffle construction which may be utilized in the embodiment of water heater 10 illustrated in FIG. 1 is shown in FIG. 9. In this alternate embodiment, the baffle comprises a divider 81 having a length corresponding to the length of flue pipe 17 and a width which is substantially the same as the inner diameter of flue pipe 17. Thus, when the baffle is placed within flue pipe 17, divider 81 divides the interior of flue pipe 17 into two sections. Attached to divider 81 are a plurality of plates 83 having an L-shaped cross section and having a semicircular shape so that the outer edge of plate 83 is in substantially continuous contact with the inner surface of flue pipe 17. Each of the plates 83 is fixedly attached to divider 81 and rests against a triangular shaped support 84. Divider 81 is provided with a plurality of openings 82 between adjacent plates 83. All of divider 81, plates 83 and supports 84 are typically constructed of sheet metal. The baffle is simply placed within flue pipe 17 by inserting in an upward direction. The bottom sides of plates 83 are preferably not fixedly attached to the top sides of supports 84. In this way, the baffle can be easily removed from flue pipe 17 for cleaning purposes simply by pulling out divider 81 in a downward direction. When the baffle is in place within flue pipe 17, the flue gases passing upwardly within pipe 17 will follow the twisted path as shown by the arrows in FIG. 9.
Surrounding the side walls of tank 11 is an insulating layer 14 typically composed of fiberglass or polyurethane foam. Surrounding insulation layer 14 is outer jacket 15. Positioned beneath tank bottom 13 is combustion chamber 20 housing gas burner 21, a pilot line 24 and gas supply line 23. A gas valve and a thermocouple circuit (not shown) is provided within control means 25 in a known manner. An emersion rod 22 is provided in order to measure the temperature of the water in the tank 11. A thermostat is provided within the control means 25, as will be described in more detail hereinafter, to regulate the operation of the burner 21.
Positioned above tank head 12 is an insulating layer 26 and a jacket top 27. Draft diverter 29 is positioned above jacket top 27 and centered over, but spaced apart from, the top end of flue pipe 17. Diverter 29 is connected to collector box 30 at opening 31. Collector box 30 is a container typically constructed of sheet metal. Thus, diverter 29 connects with opening 31 to direct the flue gases rising from flue pipe 17 into collector box 30.
Blower 34 is connected to collector box 30 through opening 32. When activated, blower 34 draws the gases within collector box 30 through opening 32 and blows them through the blower outlet 36 into flexible conduit 37. Blower 34 is typically an electric powered blower having a power cord 35.
Provided on the draft hood 29 is a thermostat 33 which is operatively connected to the blower 34 by means of the control means 25. In the event that there is a blockage in the flue gas exhaust line downstream from the draft hood 29, the rising flue gases will spill out from under the draft hood and be sensed by thermostat 33. Thermostat 33 is typically set to signal control means 25 in the event the sensed temperature rises above about 180° F. Thermostat 33, sensing the spillage of the hot flue gases from underneath the draft hood 29, will activate control means 25 to shut off the supply of fuel to burner 21. In addition, thermostat 33 will also deactivate blower 34 at this time.
Also provided within the shroud of blower 34 is a second thermostat 75 which is also typically set to signal control means 25 in the event that the temperature rises above about 180° F. This dual (i.e. thermostats 33 and 75) safety circuit system is especially preferred from an operating standpoint. In the event that there is either a total blockage of the flue gas exhaust, or if the blower 34 fails to operate, thermostat 33 quickly senses the hot flue gases spilling out from under diverter 29 and quickly signals control means 25 to cut off the supply of gas to burner 21. In the alternative, in the event of only a partial blockage of the flue gas exhaust line, thermostat 75 is the first to sense the rising flue gas temperature and quickly signals control means 25 to cut off the supply of gas to burner 21.
Turning now to FIG. 6 of the drawings, there is shown an embodiment of a direct through :-the-wall vent which is connected to the downstream end of flexible pipe 37. The term "through-the-wall" encompasses direct vents of the type which convey flue gases from an interior portion of a building or structure to an exterior portion of a building or structure for venting. Thus, for example, the term "through-the-wall" encompasses walls of all types, regardless of structure or composition, as well as other structures such as roofs and ceilings, as long as one side of the structure faces an interior space and the other side of the structure faces an exterior space into which the flue gases will be vented. In FIG. 6 there is shown a typical through the wall vent 40 mounted within a cylindrical hole 41 passing through wall 39. Within hole 41 is positioned a metal sleeve 42. An inner sleeve 44 having a face plate 45 is slid into the interior end of sleeve 42. Furthermore, face plate 45 has a circular hole 46 therein through which extends the interior end of conduit 43. Similarly, sleeve 42 has an exterior face plate 48 with a circular hole 47 through which the exterior end of conduit 43 extends. In this way, conduit 43 is annularly spaced within sleeve 42. Face plates 45, 48 are secured to the wall 39 by conventional means. Flexible pipe 37 is secured to the interior end of conduit 43 with a clamp 38.
Hingedly mounted on face plate 48 is flapper plate 50. A hinge 49 is provided for this purpose. Flapper plate 50 normally rests in a vertical position thereby acting as a damper when blower 34 is in an off cycle. However, when flue gases are flowing through flexible pipe 37 and conduit 43, the flapper plate 50 swings open to allow venting of the flue gases. A stationary plate 51 may also be provided in order to provide better protection against back flow in the conduit 43 and flexible conduit 37 in the event of high winds and the like. In the event that winds are blowing against the stationary plate 51 as indicated by the arrows, the flow of air is directed downwardly upon striking the angled plate 51. This downward flow of air causes a low pressure region 63 to form just below plate 51. This low pressure region 63 helps to draw the flue gases out of the space behind plate 51. Thus, stationary plate 51 assures proper ventilation of the flue gases even in the case of high velocity winds directed into the vent 40.
Flexible pipe 37 is preferably constructed from a wire reinforced EPDM (ethylene propylene diene monomer) rubber, which is airtight and both bendable and extendable. Flexible pipe 37 preferably has a continuous operating temperature rating above 200° F., more preferably above 250° F. Although the length of the flexible pipe 37 is not limited to any particular range, in most applications a length within the range of 6-15 feet is sufficient.
Because draft diverter 29 is spaced apart from the top end of flue pipe 17, the suction created by blower 34 draws not only the hot flue gases into collector box 30 but also draws some of the surrounding room air under diverter 29 into collector box 30. Thus, the hot flue gases are "diluted" by mixture with the ambient air. After this dilution, the gases pumped through flexible tube 37 are typically in the range of about 150°-180° F. At such low temperatures, condensation problems within flexible pipe 37 are practically eliminated. In addition, there is a much less likelihood of burn injuries to persons coming into contact with flexible pipe 37 because of this temperature dilution.
Referring now to FIGS. 2, 4 and 5, there is illustrated a second embodiment of the present invention wherein the blower 34 supplies combustion air to burner 53 while at the same time blowing the flue gases through flexible pipe 37 and out the direct vent 40. The heater 9 illustrated in FIG. 2 has a substantially airtight combustion chamber 20. Combustion air for burner 53 is provided by blower 34 and baffled tube 52. Blower outlet 36 is fluidly connected to the interior space 66 within baffled tube 52. When the blower is on, air is drawn from the space surrounding blower 34 and blown through the interior 66 of baffled tube 52. Baffled tube 52 extends into the lower portion of combustion chamber 20. Burner 53, having a "donut-shaped" configuration, wraps around the lower end of tube 52. Combustion air flows out the lower end of tube 52 as shown by the arrows and mixes with the fuel gas supplied to burner 53 allowing combustion to take place. Because chamber 20 is provided with appropriate seals to make it substantially airtight, the combustion flue gases are forced to flow upwardly within flue pipe 17 through the segmented exterior space 65.
The configuration of baffled tube 52 within flue pipe 17 is clearly illustrated in FIGS. 4 and 5. The baffled tube 52 is provided with a plurality of spiral ridges 67 along its circumference. Ridges 67 are in contact with the inside of flue pipe 17, thereby dividing the space 65 into a plurality of spiral pathways.
As the cool room air is forced through the interior space 66 it is prewarmed by countercurrent flow with the hot combustion flue gases passing upwardly through the segmented space 65. This allows for more efficient combustion of the fuel gases at burner 53.
At the top end of flue pipe 17, the exterior space 65 is open to the interior of collector box 30 through opening 31. Collector box 30 also has opening 32 connected to flexible pipe 37. In this way, the hot flue gases pass from space 65 into collector box 30 and finally into flexible pipe 37 whereby they flow out a direct vent 40.
FIG. 8 illustrates an alternate design of the collector box 30, flue pipe 17 and blower 34 which may be used with the heater 9 illustrated in FIG. 2. In this alternate design, blower 34 is positioned downstream from collector box 30 and blows the flue gases out the blower outlet 36 through flexible pipe 37. A pipe 62 is provided between opening 32 and blower 34. Thus, blower 34 provides suction to convey the flue gases from exterior space 65 into collector box 30, through pipe 62 and finally through blower 34 and flexible pipe 37. In this embodiment, tube 52 extends all the way through collector box 30 and opens at the top thereof. Because the combustion chamber 20 is airtight, the operation of blower 34 causes surrounding room air to be conveyed down the interior space 66 as shown by the arrows in order to provide combustion air to the burner 53.
FIG. 3 illustrates a "balanced flue" version of the water heater 9 illustrated in FIG. 2. In the balanced flue design, blower 34 is provided with an air inlet pipe 61 which extends to a space outside the building. In this way, combustion air is drawn by blower 34 from the outside of the building through inlet pipe 61 and blown into the interior space 65. In this design, the water heater 9 is totally "closed" with respect to the room environment since the combustion air is drawn from outside the building and the flue gases are vented directly or:tside the building.
Referring to FIG. 7, there is illustrated schematically one embodiment of a blower and burner control circuitry which may be utilized with the present invention. There is illustrated a wiring diagram 70 as well as a ladder circuit diagram. Power is provided by a 115 power supply 71. A relay contact 72 is provided to control the supply of power to blower 34. Thermostat 75, within the shroud of blower 34, provides an advance sensing control in the event that there is a partial blockage in tb:e flow of flue gases downstream from blower outlet 36. Both thermostat 75 and thermostat 33 are operatively connected to control means 25 to shut off the flow of gas to the burner in the event of any blockage or restriction of the outward flow of flue gases through flexible pipe 37.
Control means 25 is operatively connected to a pressure switch 73 through a gas line 74. In the event that the thermostat within control means 25 calls for the burner to be activated, control means 25 opens a valve thereby causing gas to flow through gas supply line 23b as well as gas line 74. The flow of gas through line 74 causes pressure switch 73 to connect thereby supplying power to blower 34. This ensures that blower 34 will be operating when the burner is turned on.
Similarly, when the thermostat indicates that the temperature of the water within tank 11 has reached a desired level, control means 25 shuts off the supply of gas to gas supply line 23b and gas line 74. Thus, pressure switch 73 is disconnected and interrupts the supply of power to blower 34.
Although this invention has been described in the specification with reference to specific forms thereof, it will be appreciated that a wide variety of equivalents may be substituted all without departing from the spirit and scope of the invention, which is defined in the appended claims. | A water heater having an insulated water tank with a cold water inlet line, a hot water outlet line and a baffled flue pipe extending vertically through the tank is provided. The flue pipe extends from a combustion chamber housing a burner located beneath the tank, to a flue gas collection chamber positioned above the tank. The collection chamber is in fluid communication with a blower and a flue gas exhaust line for conveying the flue gases through the exhaust line to a direct through-the-wall vent. Control apparatus is provided for sensing the temperature of the water in the tank and controlling the amount of fuel supplied to the burner in response thereto. The control apparatus turns on the blower when fuel is being supplied to the burner and turns off the blower when no fuel is being supplied to the burner. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of invention relates to vehicle support structures, and more particularly pertains to a new and improved vehicular carrier apparatus that includes a vertical and horizontal support organization that may be used independently or combination relative to one another.
2. Description of the Prior Art
The use of vehicular supported carrier assemblies are known in the prior art. Heretofore the assemblies have provided various grid works for support of miscellaneous articles thereon, but have been of limited structural integrity and strength for support of various items of enhanced weight in use in environments that are subject to impact. For example, U.S. Pat. No. 3,690,526 to Rundel is illustrative of the prior art utilizing a support grid wherein all of the support braces are in a single plane for support of items positioned rearwardly of a vehicle, as opposed to the rectangular cross-sectional support tubing of the instant invention.
U.S. Pat. No. 3,937,375 to Daniels provides for a unit adapted for securement to a rear bumper cantilevered relative to the rear bumper with chain members securing the item to a bottom edge of the rear bumper as the carrier is supported and cantilevered to a top edge of the bumper.
U.S. Pat. No. 3,560,443 to Haskett sets forth a bumper support organization where again the support grid is provided in a single plane relative to the bumper and is positioned overlying the associated bumper, as opposed to the instant invention wherein the horizontal support grid is positioned essentially underlying or in alignment with the lowermost edge of the bumper.
U.S. Pat. No. 1,906,920 to Sheffer provides a bumper supported framework directed horizontally of the bumper and aligned with a top edge of the bumper, wherein the grid-like framework is arranged in a single plane, as opposed to that of the instant invention.
U.S. Pat. No. 3,521,799 to Rundel provides a carrier framework that is aligned overlying the bumper utilizing strap support members to be directed interiorly of the trunk of the associated vehicle for support of the framework, as opposed to the instant invention relying on securement to the frame of the vehicle for support.
As such, it may be appreciated that there is a continuing need for a new and improved vehicular carrier apparatus which addresses both the problems of ease of use and effectiveness of construction, and as such, the instant invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of vehicular support apparatus now present in the prior art, the present invention provides a vehicular carrier apparatus wherein the same utilizes a horizontal and a vertical support carrier utilized independently or in cooperation with one another in association with a forward portion of a motor vehicle. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved vehicular carrier apparatus which has all the advantages of the prior art vehicular support apparatus and none of the disadvantages.
To attain this, the vehicular carrier apparatus includes a first and second parallel support beam of equal length for securement to the frame structure of an associated vehicle including a series of three to four equally spaced parallel grid bars secured at each terminal end by an overlying interconnecting bar with an elongate fourth grid bar overlying the interconnecting bars to provide a securement tray, wherein the bar structure is formed of rectangular cross-sectional tubing to provide integrity and rigidity to the organization. A vertical support structure includes spaced elongate bars for securement of the frame structure of the vehicle with upper and lower interconnecting bars spaced from one another by vertical bars, wherein the top interconnecting bar includes a yoke with a threaded boss and connector for receiving and securing a spare tire of the vehicle thereon. The elongate support bars extend forwardly of the bottom interconnecting bar for optionally receiving the support beams of the horizontal support structure thereon.
My invention resides not in any one of these features per se, but rather in the particular combination of all of them herein disclosed and claimed and it is distinguished from the prior art in this particular combination of all of its structures for the functions specified.
There has thus been outline, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new and improved vehicular carrier apparatus which has all the advantages of the prior art vehicular carrier apparatus and none of the disadvantages.
It is another object of the present invention to provide a new and improved vehicular carrier apparatus which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new and improved vehicular carrier apparatus which is of a durable and reliable construction.
An even further object of the present invention is to provide a new and improved vehicular carrier apparatus which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such vehicular carrier apparatus economically available to the buying public.
Still yet another object of the present invention is to provide a new and improved vehicular carrier apparatus which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is tok provide a new and improved vehicular carrier apparatus wherein the same is provided for mounting to a framework of a vehicle and to provide the use of a horizontal or vertical support structure used individually or in combination with one another.
These together with other objects of the invention, along with 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 the specific objects attained by its uses, references should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is an isometric illustration of a prior art vehicular carrier structure.
FIG. 2 is an isometric illustration of a horizontal rack as utilized by the instant invention.
FIG. 3 is an isometric illustration of the horizontal rack of FIG. 2 in association with an associated vehicle.
FIG. 4 is a horizontal rack as set forth in FIG. 2 illustrating its load carrying proportions.
FIG. 5 is an isometric illustration of a vertical rack as utilized by the instant invention.
FIG. 6 is an isometric illustration of a vertical rack with a modified tire carrier bracket secured to an associated vehicle.
FIG. 7 is an isometric illustration of the vertical rack with securement to an associated tire.
FIG. 8 is an isometric illustration of the vertical rack and horizontal rack in securement relative to one another in association with a vehicle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1 to 8 thereof, a new and improved vehicular carrier apparatus embodying the principles and concepts of the present invention.
Reference to FIG. 1 illustrates a prior art carrier rack 1 provided with a tubular upper grid 1, including spaced, tubular supports 3 underlying the grid 2 for securement to a rear bumper of an associated vehicle.
More specifically, the vehicular carrier apparatus essentially comprises a horizontal rack organization 11, as illustrated in FIG. 2 for example, utilizable individually or in combination with a vertical rack organization 12 or 12a, as illustrated in FIGS. 5 and 6 respectively.
The horizontal rack organization 11 includes a first support beam 13 of a predetermined length parallel to and spaced from a second support beam 14, wherein the beams are in general alignment with one another. A first mounting plate 15 and a second mounting plate 16 are mounted to respective rear terminal end of the respective first and second support beams 13 and 14. A series of grid bars overlie and are fixedly mounted to an upper surface of each first and second support beam and extend generally orthogonally to the elongate support beams 13 and 14. The support grid bars include a first support grid bar 17, a second support grid bar 18, and a third support grid bar 19. As illustrated in phantom, a further grid bar 17a may be utilized, wherein it is contemplated at least three such grid bars are to be employed that are directly and fixedly mounted to upper surfaces of the first and second support beams 13 and 14. The grid bars are of an equal length and are spaced a distance equally apart in a parallel aligned relationship relative to one another with a first interconnecting bar 21 and a second interconnecting bar 22 and equally mounted to upper end surfaces of the grid bars 17 through 19. A fourth grid bar 20 is mounted in an overlying relationship relative to forward terminal ends of the first and second interconnecting bars 21 and 22, as illustrated in FIG. 2, to provide a cradle structure for support of various items to be transported, such as a game deer, as illustrated in FIG. 4. The horizontal rack organization 11 is arranged to be secured to the framework of an associated vehicle 23, wherein the first and second support beams 13 and 14 underlie the lower terminal edge of the front bumper 23a of the vehicle 23 to maintain a relatively low profile of the horizontal rack 11 to enable clearance for such items as a winch, a snowplow structure and the like that is typically mounted medially of the front bumper 23a. The first and second support beams are mounted utilizing respective apertures 15a and 16a directed through the mounting plates 15 and 16 for securement to the framework of the associated vehicle 23.
FIG. 5 is illustrative of a vertical organization 12 wherein a right elongate support 24 is spaced and aligned in parallel relationship relative to a left elongate support 25. A bottom interconnecting bar 26 is positioned approximately one-third to one-half interiorly of forward terminal ends of the elongate supports 24 and 25 extending orthogonally relative to upper surfaces of the elongate supports. A right and left vertical bar 27 and 28 are each orthogonally secured to an upper surface of the bottom interconnecting bar 26 positioned somewhat interiorly of the terminal ends of the bottom interconnecting bar 26, with a top interconnecting bar 29 mounted to upper ends of the right and left vertical bars 27 and 28 to position the top interconnecting bar 29 in an overlying parallel relationship relative to the bottom interconnecting bar 26 to again provide adequate clearance on the associated bumper 23a for positioning of winches, snowplows, and the like mounted to the front bumper 23a. A positioning bar 30 is projected forwardly and orthogonally as well as medially of the top interconnecting bar 29, wherein the positioning bar 30 includes a yoke 31 to slidably receive a "T" shaped bar 33, wherein the "T" shaped bar extending upwardly of the yoke 31 is provided for positioning and impingement upon a rear surface of a tire "T" when the threaded boss and connector 32 are secured through an associated wheel rim apertures 36 of the tire "T", as illustrated in FIG. 7 for example. Alternatively, as illustrated in FIG. 6, the positioning bar 30 and its associated structure may be replaced by single "L" shaped bar 34 provided with a threaded boss and connector 35 directed orthogonally and outwardly from a forward vertical leg of the "L" shaped bar 34 that is integrally and orthogonally directed medially from the top interconnecting bar 29.
Reference to FIG. 8 illustrates the association of the vertical and horizontal racks in combination relative to one another wherein support beam apertures 13a and 14a respectively are directed orthogonally through upper and lower surfaces of a respective first and second support beam 13 and 14. The support beams 13 and 14 are of a rectangular, hollow construction and define a rectangular parallelepiped configuration interiorly thereof to receive in a complementary fashion the exterior surfaces of the forward portions of the right and left elongate supports 24 and 25 interiorly thereof. Upon slidingly receiving the right and left supports 24 and 25 interiorly of the first and second support beams 13 and 14, beam apertures 13a and 14a overlie support apertures 24a and 25a when rear terminal ends of the support beams 13 and 14 are in abutment against a forward surface of the bottom interconnecting bar 26 of the vertical rack organization 12 or 12a, as illustrated in FIG. 8. When the apertures 14a, 25a, and 13a, and 24a are in alignment, threaded bolts 37 and 38 are directed through the aligned pairs of apertures and secured by means of associated nut fasteners 37a and 38a to secure the vertical rack to the horizontal rack.
As to the manner of usage and operation of the instant invention, the same should be apparent from the above disclosure, and accordingly no further discussion relative to the manner of usage and operation of the instant invention shall be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obviousl to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A vehicular carrier apparatus utilizes a vertical and/or horizontal support grid individually or in combination relative to one another for securement to a forward portion of an associated vehicle. The horizontal carrier includes a plurality of support beams with an overlying series of mounting plates thereon to define a cradle structure wherein the vertical support member includes mounting for a spare tire relative to the organization and further, wherein the vertical and horizontal support organizations may be secured together selectively. | 1 |
This application claims the benefit of U.S. provisional patent application 60/937,361, filed Jun. 26, 2007, which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
This invention relates to collapsible/expandable prosthetic heart valve delivery systems which can house, retain, maintain, transport, deploy, help anchor, and release (and, if necessary, reposition and/or retrieve) a collapsible prosthetic heart valve via a minimally invasive (or at least reduced invasiveness) port access, e.g., at the apex of a patient's heart and through the intercostal space of the patient's ribs.
The field of collapsible/expandable prosthetic heart valves is relatively new. The general idea is to provide a prosthetic heart valve that can be collapsed to a relatively small size (diameter) for delivery into the patient with reduced invasiveness to the patient's body (typically via a tube of relatively small diameter). When the valve reaches the desired implant site in the patient, the valve is released from the delivery apparatus and expanded to its full operating size. This also includes securing the valve to tissue of the patient at the implant site.
There are several approaches to delivering and deploying such collapsible/expandable prosthetic heart valves using arterial or venous systems of the patient. However, these approaches may impose certain constraints, such as requiring smaller delivery system profiles (cross sections) so that they can be used in diseased and smaller vessels and to minimize emboli risk. This may result in undesirable trade-offs in valve design and performance in order to accommodate the demand for delivery of the valve through smaller delivery system profiles.
Ideally, the delivery system should be designed around a durable and efficient valve design, thus not compromising any of the valve's long-term implant performance requirements. In doing so, the valve design should be adequate for its intended performance and long-term durability functions. This may result in valve profiles in the collapsed state that are somewhat larger than would be appropriate for human artery or vein delivery approaches, thereby calling for an alternative route to delivering the valve to its intended implant site.
The transseptal (through the septum of the heart) antegrade (delivery in the same direction as native blood flow) approach is one approach that has been tried. In the transseptal approach, access is gained through the venous circulatory system leading to the right atrium. A puncture is made through the septum wall separating the left and right atria (hence the term transseptal). The catheter is then advanced through the mitral valve into the left ventricle and looped back up ending at the aortic valve. This approach may have some disadvantages, however. For example, it may result in damage to the mitral valve and the associated chordae when trying to gain access to the aortic valve. In contrast, the transapical (through the apex of the heart) antegrade approach may offer a better and safer alternative for entering the left ventricle (“LV”) for direct access to the aortic and mitral valves. (See, for example, P. Tozzi et al., “Endoscopic off-pump aortic valve replacement: does the pericardial cuff improve the sutureless closure of left ventricular access?”, European Journal of Cardio-thoracic Surgery 31 (2007) 22-25, available online 6 Sep. 2006.) Accessing the LV through a small port at the apex (lower end) of the heart is not new, as this has been the practice for several decades in placing bypass shunts in pediatrics. There are good, long-term, clinical experiences with this access approach to render it safe and effective. With an optimum delivery system design, safer and more effective direct access to the aortic or mitral valve can be achieved for the purposes of repair and/or replacement of defective native valves.
SUMMARY OF THE INVENTION
The delivery system of the present invention may comprise several components working together to facilitate various functions required for delivery and deployment of a collapsible/expandable prosthetic heart valve. The delivery system may include an elongated shaft attached to an ergonomic handle. The handle may incorporate several controls for several functional features within the device. One of these controls may be a rotating wheel that functions to advance/retract the valve prior to deployment and final release. Another control may be an outer shaft, which may contain a polymer sheath that functions as the valve-collapsing/expanding mechanism. Inside the outer shaft and within the sheath, there may be an internal movable shaft that is connected to the delivery device tip at the distal end of the delivery system. The shaft may be notched such that a wheel with teeth can engage and move the shaft axially when rotated in either direction (advance or retract). The prosthetic heart valve may be mounted onto this shaft and between the tip and a base. The base platform may function as a valve holding and constraining mechanism. The valve may rest on this base and can be secured in place using various mechanisms. For example, the base can have features and through-holes to allow the valve's proximal struts to be securely fastened using a suture that runs to the outside of the device at the handle on the proximal end. When the operator is satisfied with the position and orientation of the valve, the valve can be released by cutting and pulling out this suture. Alternatively, other mechanisms can be employed to secure the valve in place until final release.
The internal movable shaft may contain multi-lumens that connect manifold ports at the proximal end of the device to one or more openings at or near the distal end (tip). These lumens can be utilized for various functions such as delivery of fluids (saline, contrast, etc.) and deployment of embolic protection devices, balloons for valvuloplasty, etc.
Outside the outer shaft, a spring-loaded, donut-shaped component can be included to aid in sealing the apex of the heart or other access at the entry point by way of gentle pressure driven by the spring.
The delivery system can be manufactured from materials that are known to be biologically compatible for short-term human interaction, since this device is not a permanent implant. However, material selection should take into account the fact that this device will come into contact with a permanent implant.
The device handle can be injection molded from a bio-compatible polymer material. The elongated shaft can be polymeric or laser cut/machined surgical grade stainless steel. Internal working components can be either from a polymeric origin, stainless steel, shape-memory nitinol (nickel/titanium alloy) material, etc., depending on each component's function and performance requirements. The manifold can be an injection molded polycarbonate. The sealing donut can be made from various durometers of silicone. The device components may fit together using various means of interference fit, tabs, slots, glue, polymer heat bonds, and/or locking mechanisms to facilitate a seamless working system.
Various advantageous features of the invention are identified (to some extent recapitulating the foregoing) in the next several paragraphs.
Certain aspects of the invention relate to providing ergonomic, hand-held, easy-to-use delivery system for collapsible/expandable prosthetic heart valves. Such a delivery system may include a handle and an elongated shaft that houses the valve. The handle can incorporate controls for specific functional features within the device.
The delivery system may include valve release, retrieve, and/or reposition mechanisms.
The device may include one or more radio-opaque marker bands (e.g., at or near the distal tip) for guidance and visualization of the delivery system (especially the distal end) under fluoroscopy in the case of all-polymer construction.
The device may include precision, wheel-driven, advance/retract capabilities for precise valve positioning. Alternate mechanisms (e.g., a sliding lever) are also possible.
The device may include capabilities for fully deploying the valve but not releasing it when recapture is desired.
The device may include multi-lumen capabilities in the shaft for procedural support using ancillary devices such as guide wires, balloon catheters, embolic protection devices, fluids delivery (flushing or visualization), etc.
The valve can be secured to internal features of the delivery system using different configurations. One way is to secure the proximal end of the valve to a holder base (e.g., using sutures, mechanical interference fit features, etc.). Another way is to utilize a suture (or polymer-covered thin wire or any other appropriate means similar to this) to run from the proximal end of the device (handle) through specifically designed structures within the valve. This strand can then run through specifically designed channels in the device tip and back inside the central lumen (or other specific lumen) and end outside the device by the handle where the operator can control it. Tensioning or loosening this wire/suture will cause the valve to deploy or re-collapse. This can be used to partially deploy the valve and recapture it for repositioning or retrieval as desired.
A movable sheath, with an independent control at the handle, can function as the valve collapsing/expanding mechanism by advancing/retracting the sheath over the valve. The sheath may also maintain and protect the valve in the collapsed state. The sheath can also facilitate partial deployment and expansion of the valve, e.g., so that the operator of the apparatus can check for appropriate positioning of the valve in the patient.
The device may include features in the tip and valve holder base to control valve orientation within the delivery system so that the valve can be deployed with the correct angular orientation about its longitudinal axis, e.g., to align commissures of the prosthetic valve relative to commissures of the native valve as desired. These features can be undercuts or depressions that correspond to features on the prosthetic valve, for example.
Along with the conventional purse-string suture, a spring-loaded, silicone, molded, donut-shaped component can aid in sealing the entry port at the apex of the heart or other access into the patient's circulatory system.
The device may include the capability of opening and closing off access to any of the lumen ports at the back manifold connector.
The device tip may include features that allow the valve distal end to rest in a manner that controls the valve's collapsed diameter (e.g., to prevent damage to the stent and valve leaflets during collapse of the valve for minimally invasive delivery).
The delivery system can include a fork-like structure that can protrude and extend outside the shaft near the distal end to force open calcified native heart valve leaflets (e.g., into the sinuses of the valsalva) in preparation for valve deployment and release. Another example of an embodiment for such purposes is to deploy a structure like an umbrella. Such an umbrella design can serve two functions: (1) calcified leaflet retention, pushing such native leaflet structures out of the way in preparation for new valve deployment, and (2) embolic protection, which can be achieved by incorporating a fine mesh within the deployed ribs of the umbrella, thus capturing any emboli from the procedure. Once the procedure is completed, this umbrella can be collapsed and retracted back into the shaft, thereby safely removing from the patient all emboli and any calcified debris. An example of a structure that can be used to collapse the umbrella when desired includes a thin strand (e.g., wire or suture) attached to each of the umbrella ribs. These strands extend into the main central lumen. Pulling these strands from the proximal end causes the ribs of the umbrella to collapse.
The delivery system wheel can be centered in the handle for rotation access from both sides of the handle, or it can be offset to protrude from only one side of the device handle.
The device preferably contains seals in various areas to prevent blood from seeping through the various channels and outside the heart.
Further features of the invention, its nature and various advantages, will be more apparent from the accompanying drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified elevational view of an illustrative embodiment of apparatus in accordance with the invention.
FIG. 2 is a simplified isometric or perspective view of the FIG. 1 embodiment.
FIG. 3 is another simplified elevational view (with portions removed to reveal some of the interior) of the FIG. 1 embodiment.
FIG. 4 is a simplified isometric or perspective view of another illustrative embodiment of apparatus in accordance with the invention.
FIG. 5 is a simplified partial elevational or perspective view (with portions removed to reveal some of the interior) of the FIG. 4 embodiment.
FIG. 6 is a simplified elevational or perspective view of portions of the above-mentioned embodiments.
FIG. 7 is a simplified elevational or perspective view of portions of the FIG. 4 embodiment.
FIG. 8 is a simplified elevational view (with some portions removed) of an illustrative embodiment of apparatus that can be like the FIG. 4 embodiment, with possible additional structure in accordance with the invention.
FIG. 9 is another view that is generally like FIG. 8 , but for a later stage in use of the apparatus in accordance with the invention.
FIG. 10 is a simplified isometric or perspective view of portions of the FIG. 4 apparatus.
FIG. 11 is a simplified isometric or perspective view of portions of FIG. 8 .
FIG. 12 is a simplified isometric or perspective view of portions of FIG. 4 .
FIG. 13 is a view similar to FIG. 12 for a later stage of operation of the apparatus in accordance with the invention.
FIG. 14 is another view similar to FIG. 13 for a still later stage in operation of the apparatus in accordance with the invention.
FIG. 15 is still another view similar to FIG. 14 for an even later stage in operation of the apparatus in accordance with the invention.
FIG. 16 is yet another view similar to FIG. 15 for a still later stage in operation of the apparatus in accordance with the invention.
FIG. 17 is a simplified elevational view of an even later stage in operation of the FIG. 16 apparatus in accordance with the invention.
FIG. 18 is a simplified isometric or perspective view of what is shown in FIG. 17 .
FIG. 19 is another view similar to FIG. 18 for a still later stage in operation of the apparatus in accordance with the invention.
FIG. 20 is a simplified elevational view of what is shown in FIG. 19 .
FIG. 21 is a simplified elevational view of an illustrative embodiment of one component from several earlier FIGS.
FIG. 22 is a simplified isometric or perspective view of what is shown in FIG. 21 .
FIG. 23 is a view, similar in some respects to FIG. 4 , showing illustrative embodiments of possible additional components in accordance with the invention.
FIG. 24 is a simplified isometric or perspective view of portions of what is shown in FIG. 23 .
FIG. 25 is a simplified elevational view of what is shown in FIG. 24 .
FIG. 26 is a simplified isometric or perspective view of portions of what is shown in FIGS. 23-25 .
FIG. 27 is a simplified, partial, elevational view, partly in section, showing an illustrative embodiment of possible features in accordance with the invention.
FIG. 28 is a simplified sectional view showing an illustrative embodiment of other possible features in accordance with the invention.
FIG. 29 is a simplified, partial, elevational view, partly in section, showing an illustrative embodiment of still other possible features in accordance with the invention.
FIG. 30 is a simplified perspective or isometric view of an illustrative embodiment of a structure that can be used in apparatus in accordance with the invention.
DETAILED DESCRIPTION
An illustrative embodiment of prosthetic heart valve delivery apparatus 10 in accordance with the invention is shown in FIG. 1 . FIG. 1 and several subsequent FIGS. omit all depiction of the prosthetic valve, but several still later FIGS. do show examples of such valves. The components of apparatus 10 that are visible in FIG. 1 include handle 20 , control wheel 30 , outer shaft 40 , inner shaft 50 , distal tip 60 , and proximal (back) manifold connector 70 . Elements 40 and 70 are both fixed to handle 20 . Control wheel 30 is rotatable about an axis (perpendicular to the plane on which FIG. 1 is drawn) to cause shaft 50 (and distal tip 60 ) to advance or retract relative to shaft 40 , depending on the direction of rotation of the control wheel. Distal tip 60 is fixed on the distal end of shaft 50 . Connector 70 may include one or more lumens that communicate with one or more lumens through other components of the apparatus.
Elements 20 , 30 , and 70 remain outside the patient at all times. Elements 40 , 50 , and 60 are designed for insertion into a patient's body in a low invasiveness manner to deliver a prosthetic heart valve into the patient and to deploy (implant) that prosthetic heart valve in the patient. More particularly, the prosthetic heart valve is initially contained (in a collapsed condition) in a distal portion of apparatus 10 (i.e., inside shaft 40 , concentrically around shaft 50 , and abutting distal tip 60 ). In this condition of the apparatus, shaft 40 may help to keep the valve collapsed, and distal tip 60 (which is proximally retracted) may help to keep the valve inside shaft 40 . When the distal portion of the apparatus reaches the desired implant site for the valve in the patient, wheel 30 can be rotated to extend distal tip 60 , a distal portion of shaft 50 , and the prosthetic heart valve from the distal end of shaft 40 . This allows the prosthetic heart valve to expand radially outwardly from shaft 50 to its full operating size, which also causes the valve to engage surrounding native tissue of the patient and thereby implant in the patient. The apparatus can then be withdrawn (proximally) from the patient. In particular, distal tip 60 comes out through the center of the now-expanded valve.
More details regarding the foregoing will be provided later in this specification.
It should be noted that in the FIG. 1 embodiment, shaft 40 is off-center relative to handle 20 (i.e., shaft 40 is somewhat below the top-to-bottom center of handle 20 ). On the other hand, wheel 30 is centered on handle 20 and is exposed for operation from either above or below the handle.
FIGS. 2 and 3 show other views of apparatus 10 . FIG. 3 shows apparatus 10 with half of handle 20 removed. This exposes the connection between wheel 30 and shaft 50 . In particular, it shows that there is a spur gear 32 on wheel 30 concentric with the axis of rotation of wheel 30 . This spur gear engages with a rack 52 on shaft 50 . These features allow rotation of wheel 30 to cause translation of shaft 50 along its longitudinal axis. (Features of this kind may be seen even more clearly for another embodiment in FIG. 5 .)
An alternative embodiment of device 10 is shown in FIG. 4 . Even though the FIG. 4 embodiment is somewhat different than the FIGS. 1-3 embodiment, the same reference numbers continue to be used for generally similar elements. Thus additional information for such elements can be gleaned from earlier description of those elements, and it will not be necessary to repeat everything previously said for elements that are used again (at least in generally similar form) in different embodiments.
The FIG. 4 embodiment is different from the FIGS. 1-3 embodiment in that in FIG. 4 shaft 40 is centered (from top to bottom) on handle 20 . Another difference is that in FIG. 4 , control wheel 30 is only operable from the top of handle 20 .
FIG. 4 shows the possible addition of a toroidal or donut-shaped sealing ring 80 disposed concentrically around an intermediate portion of the length of shaft 40 . Ring 80 fits relatively closely around the outside of shaft 40 , but ring 80 is also axially slidable along shaft 40 . If ring 80 is moved in the proximal direction from the approximate starting position shown in FIG. 4 , coil spring 90 (also disposed concentrically around shaft 90 ) acts to resiliently urge it back toward the starting position. Ring 80 can be located along shaft 40 so that when the distal portion of shaft 40 is pushed through an opening (aperture) in the apex of the patient's heart or other access to the patient's circulatory system, ring 80 bears against the outer surface of the tissue around the aperture and helps to reduce blood leakage from the circulatory system via the aperture. Spring 90 keeps ring 80 resiliently pressed against the outside of the tissue for this purpose. Ring 80 may be made of a softer material than other components of apparatus 10 . For example, ring 80 may be made of silicone.
FIG. 5 shows an enlargement of a portion of the FIG. 4 embodiment with part of handle 20 removed. Thus FIG. 5 shows the spur gear 32 on wheel 30 engaging the rack 52 on shaft 50 as described earlier in connection with FIG. 3 . FIG. 5 also shows a tube 100 that may extend from connector 70 to a distal portion of the apparatus. For example, tube 100 may extend to opening 62 in the distal end of tip 60 for allowing fluid introduced via connector 70 to be released into the patient from the distal end of tip 60 for such purposes as providing fluoroscopically visible contrast in the patient. There may be more than one such tube 100 , which may go to different destinations in the device, and which may be for different purposes. Note that shaft 50 may be translatable axially (i.e., lengthwise) relative to tube 100 .
FIG. 6 shows portions of elements 40 and 50 and element 60 on a larger scale. FIG. 7 does the same for a portion of element 20 and element 70 . FIG. 7 also shows that element 70 may include a valve 72 for selectively closing a lumen through that element. In particular, valve 72 may be controlled by the operator of the apparatus to close a lumen through connector 70 , e.g., to prevent blood from escaping from the patient via that lumen. When desired, the operator may open valve 72 , e.g., to allow fluid or some other auxiliary material or apparatus to be introduced into the patient via the associated lumen. Depicted valve 72 may be repeated for other lumens if desired.
FIG. 8 shows an illustrative embodiment of a possible addition to what has been shown before. In particular, FIG. 8 shows that a plurality of fingers 110 may be selectively deployed from the distal end of shaft 40 (when distal tip 60 is moved somewhat away from that distal shaft end) to push back native leaflets of a patient's native heart valve (which is going to be replaced by the prosthetic heart valve delivered by device 10 ). Fingers 110 may be initially confined in an annular array inside a distal portion of shaft 40 . When it is desired to deploy them (typically when the distal portion of the apparatus is appropriately positioned relative to the native valve that is to be replaced), fingers 110 can be pushed (part way) from the distal end of shaft 40 , and they then resiliently extend (radially) out farther from central shaft 50 , albeit still in an annular array as shown in FIG. 8 . In this condition, fingers 110 push back the leaflets of the native valve (e.g., into the patient's native valsalva sinus) in order to help make appropriate room for deployment of the prosthetic valve within the native valve. As shown in FIG. 30 , fingers 110 may be attached to a shaft 112 that runs longitudinally inside shaft 40 into handle 20 . Fingers 110 and their shaft 112 can be advanced or retracted relative to shaft 40 via a sliding control, lever, or the like that is on the outside of handle 20 . For example, FIG. 30 shows a control member 114 attached to the proximal end of shaft 112 . Control member 114 can project from a slot in a side of handle 20 , where it can be manipulated by the user of the apparatus to advance or retract fingers 110 . Alternatively, control member 114 may connect to another actuator element on handle 20 for the same purpose as described in the preceding sentence.
FIG. 9 shows a structure similar to what is shown in FIG. 8 , with the addition of prosthetic valve 200 now deployed from near the distal end of the apparatus. Subsequent FIGS. show valve 200 and its deployment on a larger scale and in more detail, so more detailed discussion of the valve will be provided later in connection with those other FIGS. Here it is preliminarily noted that the principal components of valve 200 include an annular framework 210 (e.g., of metal) and a plurality of flexible valve leaflets 220 disposed within and mounted on that framework. Framework 210 and leaflets 220 are radially collapsible to a circumferential size that can fit inside shaft 40 . However, when shifted beyond the distal end of shaft 40 as shown in FIG. 9 , framework 210 can resiliently expand (as shown in FIG. 9 ), carrying leaflets 220 with the frame and positioning those leaflets relative to one another so that they can operate as a one-way, blood flow, check valve (like the native heart valve being replaced).
FIG. 10 shows elements 80 and 90 (and portions of neighboring elements) on a still larger scale. FIG. 11 does the same for elements 110 and portions of neighboring elements. Note the opening 62 in the distal end of tip 60 , which opening may communicate with a lumen through above-described tube 100 .
FIGS. 12-20 show an illustrative embodiment of how valve 200 may be deployed. These FIGS. focus on valve 200 and the distal portion of delivery apparatus 10 . FIG. 12 shows this portion of the apparatus in the condition that it has as it is being introduced into the patient (e.g., via an aperture in the apex of the patient's heart). Note that tip 60 is against the distal end of shaft 40 to give this portion of the apparatus a smooth exterior surface.
When the distal portion of apparatus 10 reaches the desired location in the patient (i.e., the desired location for implanting the prosthetic heart valve), distal tip 60 and some associated structure may be displaced distally from the distal end of shaft 40 as shown in FIG. 13 . This may be done by rotating wheel 30 . In addition to what has been shown in earlier FIGS., FIG. 13 shows that the apparatus may include a sleeve 120 around the outside of collapsed valve 200 , but inside collapsed fingers 110 . This sleeve may help to protect valve 200 from fingers 110 , and it may also facilitate the staged deployment of valve 200 . As FIG. 13 shows, sleeve 120 initially moves in the distal direction with tip 60 and other elements that are inside sleeve 120 .
The next step is shown in FIG. 14 . In this step, fingers 110 are pushed part way out of the distal end of shaft 40 so that these distal portions of fingers 110 can spread radially outwardly and thereby push back the leaflets of the patient's native heart valve. A point should be made here as follows. FIG. 14 and subsequent FIGS. may show the apparatus that is inside deployed fingers 110 at locations that are more distal to fingers 110 than would actually be the case. For example, elements 120 and 60 may not be distally as far from fingers 110 after deployment of those fingers as is shown in FIG. 14 (and subsequent FIGS.). Instead, valve 200 may be deployed closer to deployed fingers 110 than the FIGS. alone may suggest. The FIGS. deviate from what may be the actual practice in this respect so that various parts can be seen more clearly (i.e., without overlapping and thereby obscuring one another).
The next step is illustrated by FIG. 15 . In this step, sleeve 120 is pulled back proximally to begin to expose prosthetic heart valve 200 . Although not shown in full detail in FIG. 15 to avoid over-complicating the drawing, the distal portion of heart valve 200 typically begins to deploy (i.e., expand radially outwardly as indicated by arrows 202 ) as it is released from confinement within sleeve 120 . Thus the actual condition of valve 200 in FIG. 15 is typically more like what is shown in FIG. 29 (i.e., distal portion of valve (beyond sleeve 120 ) expanded radially out; proximal portion of valve (still within sleeve 120 ) still prevented by sleeve 120 from expanding radially out).
FIG. 16 shows sleeve 120 pulled proximally back even farther so that valve 200 is now completely exposed. Once again, to avoid over-complicating the drawing, FIG. 16 omits the fact that at this stage heart valve 200 is typically expanded radially outwardly along its entire length as indicated by the arrows 202 and 204 in FIG. 16 and as is actually shown in FIG. 17 . FIG. 16 does, however, serve to illustrate the point that prior to the deployment of valve 200 (i.e., prior to its radial outward expansion), the axial position of the collapsed valve is maintained in the apparatus by positioning the valve between distal tip 60 and a more proximal collar 140 on shaft 50 .
FIGS. 17 and 18 show additional structure that may be included in accordance with the invention. This is a system of flexible strands 130 that may be used (in conjunction with distal re-advancement of sleeve 120 ) to re-collapse valve 200 (either partly or wholly) in the event that it is found desirable or necessary to reposition the valve in the patient or to completely remove the valve from the patient after the valve has been partly or wholly expanded radially outwardly in the patient. FIGS. 17 and 18 show the routing of strands 130 in this embodiment. A typical strand 130 comes from a proximal portion of the apparatus between shaft 50 and sleeve 120 . The strand 130 passes through an aperture in collar 140 , and then runs along the outside of valve 200 to an aperture in distal tip 60 . The strand passes through the interior of tip 60 , and then through the central lumen of shaft 50 , extending proximally all the way to the handle, where the strand ends can be controlled by the operator of the apparatus. There can be any number of similarly routed strands 130 spaced in the circumferential direction around the apparatus and valve 200 . Strands 130 are shown in a relatively loose or relaxed condition in FIGS. 17 and 18 . However, they can be tightened by pulling on their proximal portions.
An example of how strands 130 may be used is as follows. The gradual proximal retraction of sleeve 120 (described in earlier paragraphs) allows heart valve 200 to gradually deploy radially outwardly. Strands 130 are relaxed or loose at this time. The gradual deployment of valve 200 may be observed by the operator of the apparatus (e.g., via x-ray, fluoroscopy, or the like). If the valve is not going in as desired, expansion of the valve can be stopped by stopping the proximal retraction of sleeve 120 . Strands 130 can then be tightened by pulling proximally on their proximal portions, and at the same time sleeve 120 can be pushed in the distal direction. This combination of tightening strands 130 and pushing distally on sleeve 120 causes valve 200 to collapse back into the sleeve. The apparatus can then be repositioned to reposition valve 200 in the patient (after which the valve can be deployed again), or alternatively the valve can be completely removed from the patient with all of the surrounding instrumentation. Assuming that the valve remains in the patient, then when the operator of the apparatus is satisfied with its deployed position and condition, strands 130 can be removed (or effectively removed) by pulling on one proximal portion of each strand until the other end of that strand has been past valve 200 two times (once going in the distal direction, and then going in the proximal direction). FIGS. 19 and 20 show the condition of the apparatus after strands 130 have thus been removed (or effectively removed).
Strands 130 can be made of any suitably tensilely strong but laterally (transversely) flexible material. Examples include suture material, metal wire, or the like.
Because FIGS. 19 and 20 show valve 200 in the fully deployed condition and after strands 130 have been removed, these FIGS. offer the clearest views of valve 200 and therefore afford the best reference for the following further description of the valve. Although this description is provided in connection with FIGS. 19 and 20 , it will be understood that the valve can be the same in all of the earlier-discussed FIGS. herein. On the other hand, it will also be understood that this particular construction of the prosthetic heart valve is only an example, and that many modifications, variations, and alternatives are also possible for the valve.
As was mentioned earlier in this specification, principal components of valve 200 include frame 210 (e.g., of a highly elastic metal such as nitinol) and a plurality of leaflets (e.g., three leaflets) 220 of a flexible material such as tissue that has been rendered effectively inert and otherwise made suitable for long-term, non-reactive use in a patient's body. Leaflets 220 are secured to frame 210 in such a way that the leaflets can open (to allow blood to flow through the valve from left to right as viewed in FIGS. 19 and 20 ) and close (to prevent blood from flowing through the valve from right to left as viewed in these FIGS.).
The illustrative configuration of valve 200 that is shown in the FIGS. herein is particularly adapted for use as a prosthetic aortic valve. Details of valve 200 will therefore be described in that context. It will be understood, however, that this is only an example, and that the prosthetic valve can be alternatively configured differently in some respects to adapt it for use as a replacement for other valves in the heart or circulatory system.
Frame 210 is preferably a continuous, one-piece, annular (ring-like) structure (e.g., a structure that has been cut (using a laser) from a tube and then further processed to achieve a desired shape). Frame 210 has a “lower” (upstream or blood inflow) portion 212 that extends in a serpentine (undulating or zig-zag) fashion all the way around the valve. This portion of frame 210 may be designed for implanting in or near the patient's native valve annulus. Frame 210 also includes an “upper” (downstream or blood outflow) portion 216 that also extends in a serpentine (undulating or zig-zag) fashion all the way around the valve. This portion of frame 210 may be designed for implanting in the patient's aorta downstream from the valsalva sinus of the patient. Frame portions 212 and 216 are connected to one another by a plurality of links or struts 214 that extend between those other frame portions at locations that are spaced from one another around the valve. Struts 214 may bow or bulge radially outwardly (as shown) to follow the inner surface of lobes of the valsalva sinus.
Frame 210 may include commissure post members 218 that extend up from lower portion 212 at appropriate locations around the valve (analogous to the commissures of the patient's native heart valve). These posts 218 can form important portions of the frame structure to which leaflets 220 are attached.
Frame 210 may also include other structures 219 that extend up and incline radially out from lower portion 212 to help hold back the patient's native valve leaflets, which (to the extent left remaining in the patient) are no longer functional.
Frame 210 may also include barbs (e.g., 211 ) at various locations to engage (and possibly penetrate) the patient's native tissue to help hold the valve in place where deployed in the patient.
The point of making annular frame portions 212 and 216 serpentine is to facilitate annular (circumferential, radial) collapse and subsequent re-expansion of the valve. Such collapse is preferably elastic, and the subsequent re-expansion is preferably resilient.
Although not shown herein, it will be understood that valve 200 may also include other components such as one or more layers of fabric and/or tissue on various parts of the valve. Such additional layers may be for such purposes as to promote tissue in-growth, to reduce the amount of contact between frame 210 and surrounding native tissue, to prevent moving portions of leaflets 220 from contacting frame 210 , etc.
Illustrative details for collar 140 are shown in FIGS. 21 and 22 . These features may include a distally extending, radially outer rim 142 , within which a proximal portion of valve 200 can be received when the valve is in the collapsed condition. This structure 142 can help to keep valve 200 confined to its collapsed condition prior to deployment.
Other features of collar 140 may include recesses or sockets 144 , into which extreme proximal portions (e.g., 211 ) of frame 210 may extend when valve 200 is in the collapsed condition. Such engagement between frame 210 and collar 140 can help ensure that valve 200 always maintains a known rotational (angular) orientation about the longitudinal axis of the apparatus. This can be helpful to ensure that rotation of apparatus 10 about its longitudinal axis produces exactly the same rotation of valve 200 about that axis. This may be important, for example, to help the operator of the apparatus position valve 200 for deployment with commissure posts 218 in a desired rotational or angular position relative to the patient's native valve commissures. As a specific example, it may be desirable for each commissure post 218 to be aligned with and inside a respective one of the patient's native valve commissures. This may necessitate rotation of apparatus 10 about its longitudinal axis, and features like 144 (with certain valve frame features received within those features 144 ) can help ensure that valve 200 has a known angular relationship to apparatus 10 , and that this angular relationship is always maintained until the valve is deployed from the apparatus. Snug engagement between collar 140 and shaft 50 is also part of this aspect of the invention in this embodiment.
Still other possible features of collar 140 are apertures 146 for passage of above-described strands 130 through the collar.
FIGS. 23-26 illustrate another possible feature of the apparatus. This is an embolic protection structure 300 , which may also include features for pushing back the leaflets of the native heart valve that is to be replaced by the prosthetic valve. Structure 300 will now be described.
A purpose of apparatus 300 is to capture any debris (e.g., emboli) that may be dislodged from inside the patient during deployment of prosthetic heart valve 200 and/or the expansion of fork fingers 110 . Thus embolic protection apparatus 300 is typically deployed in the patient, early in the procedure, downstream from the location at which valve 200 will be deployed. For example, assuming that valve 200 is a replacement for the patient's native aortic valve, apparatus 300 may be deployed in the patient's aorta downstream from where the prosthetic valve will be employed. Apparatus 300 acts like a blood filter. It allows blood to flow through, but it captures any particles or the like that should not be allowed to remain in the patient's blood stream. After prosthetic valve 200 has been implanted, apparatus 300 is collapsed (still retaining any debris it has captured) and removed from the patient in the opposite way from which it was introduced.
In this embodiment, apparatus 300 is a structure somewhat like an umbrella. In particular, structure 300 has a central shaft 310 , and a plurality of ribs or spokes 320 that are attached to a distal portion of shaft 310 and that can either collapse inwardly against (parallel to) shaft 310 or that can incline radially outwardly from shaft 310 . Another element of structure 300 is a flexible, emboli-catching web or mesh (blood filter) 330 attached to ribs 320 . Still other components of structure 300 are tethers 340 (shown only in FIG. 26 to avoid over-complicating the other FIGS.). Tethers 340 run inside the proximal portion of shaft 310 and come out of apertures in the side wall of shaft 310 at locations that are adjacent to ribs 320 . Each tether 340 is attached to a respective one of ribs 320 .
Before deploying valve 200 , apparatus 300 may be introduced into the patient in a collapsed condition via proximal connector 70 , a lumen through tube 100 , and distal tip aperture 62 . When apparatus 300 is at the desired location in the patient's circulatory system downstream from where valve 200 is to be implanted, the proximally directed tension on proximal portions of strands 340 may be released. This allows ribs 320 to resiliently deflect outwardly into an array somewhat like the ribs or spokes of an open umbrella. Ribs 320 carry out with them, and thus also open, blood filter web 330 . These structures (i.e., 320 and 330 ) preferably bear against an annular portion of the inner surface of a blood vessel (e.g., the aorta) downstream from where valve 200 will be implanted in the patient.
After valve 200 has been deployed, embolic protection apparatus 300 may be collapsed again by pulling proximally on tethers 340 . This causes ribs 320 to again become parallel to and against central shaft 310 . Blood filter 330 (with any captured debris) is thereby also collapsed against central shaft 310 . This allows apparatus 300 to be pulled back into device 10 via the aperture 62 in distal tip 60 .
Note that apparatus 300 may include ribs 320 that extend proximally back from blood filter 330 per se. These rib extensions may serve the additional function of pushing back (radially outwardly) the leaflets of the patient's native heart valve prior to deployment of prosthetic valve 200 .
After apparatus 300 (with above-mentioned, optional, proximal, rib extensions) has been deployed, the distal portion of device 10 may be moved distally closer to apparatus 300 . The distal portion of device 10 may then be opened and valve 200 may be deployed as shown in FIGS. 23-25 . Because in this embodiment, deployed valve 200 may somewhat axially overlap with the proximal extensions of ribs 320 , after deployment of valve 200 , apparatus 300 may first be pushed in the distal direction to eliminate this overlap so that apparatus 300 can be re-closed without disturbing implanted valve 200 . This is also a convenient point to mention that after valve 200 has been deployed (in any embodiment, with or without apparatus 300 ), shaft 40 may be pushed distally through the implanted valve to again close against distal tip 60 . This restores the smooth outer surface to device 10 , which facilitates proximal withdrawal of device 10 through the implanted valve without disturbing the valve. If apparatus 300 is employed, it is preferably collapsed and returned to the interior of device 10 (or completely removed via device 10 ) prior to full withdrawal of device 10 through the implanted valve.
FIG. 27 shows that a lumen through elements 70 , 100 , 60 , 62 can be used for passage of a guide wire 400 through the apparatus. Thus a guide wire 400 can first be placed in the patient, and device 10 can thereafter be introduced into the patient by following along this guide wire. This guide wire lumen and/or other similar lumens through device 10 can alternatively or additionally be used for other purposes such as flushing, introduction and/or removal of other ancillary devices (e.g., embolic protection apparatus 300 ), etc.
FIG. 28 shows other possible aspects of valve deployment and retrieval. FIG. 28 shows the upstream end of valve 200 inside sheath 120 and bearing on collar 140 . Suture or wire strands 500 pass through collar 140 and are looped through upstream portions 212 of valve frame 210 . Strands 500 can be pulled in the proximal direction to hold the proximal (upstream) end of valve 200 against collar 140 . This also prevents the proximal end of valve 200 from expanding radially outwardly (even when sheath 120 is retracted proximally). However, when sheath 120 is retracted proximally past the proximal end of valve 200 and the tension on strands 500 is relaxed, the proximal end of valve 200 can expand resiliently outwardly. ( FIG. 29 shows this structure again (although it omits depiction of strands 500 to avoid over-complicating the drawing) with the distal (downstream) portion of valve 200 released from sheath 120 and resiliently expanded outwardly, but with the proximal portion of the valve not yet released.)
FIGS. 28 and 29 show that the distal end of sheath 120 may flare radially outwardly as shown at 122 . This feature and strands 500 can be used to re-collapse valve 200 prior to its final release from device 10 if for any reason it is desired to reposition the valve in the patient or remove the valve from the patient. A combination of pulling proximally on strands 500 and pushing sheath 120 distally can be used to collapse valve 200 back down into sheath 120 with the proximal end of the valve seated against collar 140 . The valve can then either be positioned differently in the patient and again deployed, or the valve can be completely removed from the patient with device 10 . Assuming that valve 200 is going to be implanted in the patient, when the operator of the apparatus is satisfied with the placement of the valve in the patient, the valve is finally released from device 10 by allowing the downstream end of the valve to deploy and anchor against the aortic wall, and then deploying the upstream valve end. Finally, strands 500 are removed by releasing one end of each strand loop and using the other end of that loop to pull the released end sufficiently far so that the strand no longer prevents release of the valve from device 10 .
It will be understood that the foregoing is only illustrative of the principles of the invention and that various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. For example, the shapes and sizes of various components can be different from the shapes and sizes employed in the illustrative embodiments shown herein. As another example, the lateral stiffness of shaft 40 and/or other longitudinal elements within shaft 40 can be selected to render the apparatus suitable for different possible uses and/or preferences. Thus in some embodiments it may be desirable for the shaft portion of the apparatus to be relatively stiff or even rigid or substantially rigid (i.e., not flexible or bendable transverse to or laterally of its longitudinal axis). On the other hand, in other embodiments it may be desirable for the shaft portion of the apparatus (or certain parts of the shaft portion) to be more laterally flexible. | Apparatus for delivering a prosthetic heart valve into a patient by means that are less invasive than conventional open-chest, open-heart surgery. The prosthetic valve may be collapsed while in a delivery device. When the valve reaches the desired implant site in the patient, the valve can be released from the delivery device, which allows the valve to re-expand to the configuration in which it can function as a heart valve. For example, the delivery device may be constructed to facilitate delivery of the prosthetic valve into the patient via the apex of the patient's heart. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 12/758,767 filed Apr. 12, 2010, and incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for fabricating a semiconductor device, and more particularly, to a method for fabricating a semiconductor device with mini SONOS cells.
2. Description of the Prior Art
With increasing shrinkage of semiconductor devices, the integration degree is doubled every three years according to a scaling rule, and speed of semiconductor devices is increasing and power consumption thereof is decreasing. The production of finer MOS type FETs has been being accomplished by decreasing a dimension of a gate electrode, decreasing a thickness of a gate insulating layer and highly accurately controlling an impurity concentration profile in a channel forming region or in its vicinity. And, driving capability of semiconductor devices is improved and a parasitic capacitance thereof is decreased according to finer semiconductor devices. In general, in circuits having a CMOS structure, an operating rate is determined depending upon a rate of charging (or discharging) for giving an output of a logic gate at a certain stage to drive a capacitive load in a subsequent logic gate. Therefore, the operating rate is in proportion to the inverse number of capacity of the capacitive load and to the driving capability.
For accomplishing the formation of finer semiconductor devices, conventionally, there has been employed a logic gate structure adjacent to the MOS structure, i.e., a structure having a logic gate composed of a gate oxide layer and polysilicon gate electrode layer is disposed on a semiconductor substrate while the edges of the logic gate is sitting on a portion of two adjacent shallow trench isolations (STIs), in which a depletion region is created directly under the logic gate and between the two STIs. In this structure, as at least a portion of the STI is overlapped by the gate oxide layer of the logic gate, an inevitable edge fringing capacitance is created at the overlapped region, which in most circumstances, would induce an inverse narrow width effect.
SUMMARY OF THE INVENTION
It is an objective of the present invention to propose a novel structure and fabricating method thereof for resolving the aforementioned issues typically found in conventional semiconductor devices with logic gate.
A semiconductor device with mini silicon-oxide-nitride-oxide-silicon (mini-SONOS) cell is disclosed. The semiconductor device includes: a semiconductor substrate; a shallow trench isolation (STI) embedded in the semiconductor substrate; a logic device partially overlapping the STI; and a SONOS cell formed in the overlapped region of the logic device and the STI.
According to another aspect of the present invention, a semiconductor device with mini silicon-oxide-nitride-oxide-silicon (mini-SONOS) cell is disclosed. The semiconductor devices includes: a semiconductor substrate; a shallow trench isolation (STI) embedded in the semiconductor substrate; a logic device partially overlapping the STI; a first SONOS cell formed in a first overlapped region of the logic device and the STI; and a second SONOS cell formed in a second overlapped region of the logic device and the STI.
According to another aspect of the present invention, a method for fabricating a semiconductor device with mini-SONOS cell is disclosed. The method includes the steps of: providing a semiconductor substrate having a first MOS region and a second MOS region; forming a first trench in the semiconductor substrate between the first MOS region and the second MOS region; depositing a oxide liner and a nitride liner in the first trench; forming a STI in the first trench; removing a portion of the nitride liner for forming a second trench between the first MOS region of the semiconductor substrate and the STI and a third trench between the STI and the second MOS region of the semiconductor substrate; and forming a first conductive type nitride layer in the second trench.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-9 illustrate a method for fabricating a semiconductor device with two mini silicon-oxide-nitride-oxide-silicon (mini-SONOS) cells according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION
Referring to FIGS. 1-9 , FIGS. 1-9 illustrate a method for fabricating a semiconductor device with two mini silicon-oxide-nitride-oxide-silicon (mini-SONOS) cells according to a preferred embodiment of the present invention. As shown in FIG. 1 , a semiconductor substrate 12 preferably composed of silicon is provided, and a pad oxide (not shown) and a pad nitride (not shown) are deposited on the substrate 12 . A series of photo-etching processes are performed by using a patterned photoresist (not shown) to first remove a portion of the pad nitride for forming a patterned pad nitride 16 , and then using the patterned pad nitride 16 as mask to remove a portion of the pad oxide and the substrate 12 for forming a patterned pad oxide 14 and a trench 18 . Despite a series of photo-etching processes are preferably utilized to form the trench 18 , only one photo-etching process could also be employed to remove a portion of the pad nitride, the pad oxide, and the substrate simultaneously for forming the trench 18 , which is also within the scope of the present invention.
As shown in FIG. 2 , a composite layer composed of an oxide liner 20 and a nitride liner 22 is deposited in the trench 18 while covering the top surface of the pad nitride 16 and the sidewall of the pad nitride 16 , the pad oxide 14 , and the substrate 12 .
As shown in FIG. 3 , a high density plasma (HDP) oxide deposition is performed to deposit a layer (not shown) preferably composed of oxide in the trench. The deposition of the oxide layer preferably fills the entire trench 18 and covering the surface of the nitride liner 22 . A chemical mechanical polishing (CMP) process and an etching back are conducted thereafter to remove a portion of the oxide layer, the nitride liner 22 , and the oxide liner 20 . Preferably, the CMP process removes the oxide layer, the nitride liner 22 and the oxide liner 20 deposited on the top surface of the pad nitride 16 until the top surface of pad nitride 16 is exposed, and the etching back process then removes the remaining oxide layer until the top surface of the oxide layer is lower than the top surface of the pad nitride 16 . The combination of the CMP process and the etching back process preferably forms a shallow trench isolation (STI) 24 in the trench 18 .
As shown in FIG. 4 , an etching process is conducted by utilizing phosphoric acid to remove the pad nitride 16 entirely and a portion of the nitride liner 22 and the oxide liner 20 to form a plurality of trenches 26 between the remaining oxide liner 20 and the STI 24 . The depth of the trenches 26 could be adjusted by altering parameters of the phosphoric acid etching, and as a portion of the nitride liner 22 is etched away, the trenches 26 preferably expose a portion the sidewall of the oxide liner 20 and the STI 24 and the remaining nitride liner 22 . It should be noted that as the thickness of the deposited oxide liner 20 is preferably controlled between 10-20 Angstroms and the thickness of the pad oxide 14 is controlled between 110-120 Angstroms, the etching process preferably removes the oxide liner 20 between the pad nitride 16 and the nitride liner 22 along with the entire pad nitride 16 and part of the nitride liner 22 while leaving the pad oxide 14 intact.
As shown in FIG. 5 , a PMOS region 28 and a NMOS region 30 are defined on the substrate 12 , and a p-type nitride layer, such as a boron doped nitride layer 32 is deposited to cover both the PMOS region 28 and the NMOS region 30 of the substrate 12 . The boron doped nitride layer 32 is preferably deposited on the surface of the pad oxide 14 and the STI 24 while filling the trenches 26 entirely.
As shown in FIG. 6 , a wet etching, such as through a photo-etching process is carried out to remove a portion of the boron doped nitride layer 32 from the NMOS region 30 of the substrate 12 and the boron doped nitride layer 32 filled in the trenches 26 between the STI 24 and the NMOS region 30 of the substrate 12 as the remaining boron doped nitride layer 32 is disposed on the PMOS region 28 of the substrate 12 and a portion of the STI 24 .
As shown in FIG. 7 , an n-type nitride layer, such as a phosphorus doped nitride layer 34 is deposited on the NMOS region 30 and the PMOS region 28 of the substrate 12 while covering the boron doped nitride layer 32 . The deposited phosphorus doped nitride layer 34 is preferably filled in the trench 26 between the STI 24 and the NMOS region 30 of the substrate 12 as the rest of the layer 34 is disposed on the STI 24 and the boron doped nitride layer 32 .
As shown in FIG. 8 , a wet etching is conducted by using phosphoric acid to remove the boron doped nitride layer 32 and the phosphorus doped nitride layer 34 from the surface of the pad oxide 14 and the STI 24 . After the boron doped nitride layer 32 and the phosphorus doped nitride layer 34 are removed, another etching process is performed by using hydrofluoric acid to remove the remaining pad oxide 14 . It should be noted that despite a boron doped nitride layer 32 and a phosphorus doped nitride layer 34 are deposited in the adjacent trenches 26 respectively, the trenches 26 could also be filled with a nitride layer with only one conductive type. For instance, after the boron doped nitride layer 32 (or a phosphorus doped nitride layer) is deposited into the two trenches 26 , as shown in FIG. 5 , the two etching processes addressed in FIG. 8 could be carried out directly to first remove the boron doped nitride layer 32 from the surface of the pad oxide 14 and STI 24 while leaving the remaining boron doped nitride layer 32 in the two trenches 26 and then remove the pad oxide layer 14 . This approach is also within the scope of the present invention.
Next, as shown in FIG. 9 , a gate oxide layer 36 and a polysilicon layer 38 are formed on the surface of the semiconductor substrate 12 and the STI 24 , in which the gate oxide layer 36 and the polysilicon layer 38 deposited are preferably the gate oxide layer and polysilicon gate electrode layer formed in the MOS region. This completes the fabrication of a semiconductor device according to a preferred embodiment of the present invention.
By following the fabrication method revealed from FIGS. 1-9 , a semiconductor device with two mini silicon-oxide-nitride-oxide-silicon (mini-SONOS) cells is accomplished, in which the gate oxide layer 36 and the polysilicon layer 38 together constitute a logic gate 40 of the semiconductor device, and two mini-SONOS cells 42 , 44 are formed at the overlapped region of the logic gate 40 and the STI 24 .
Preferably, the semiconductor device includes a semiconductor substrate 12 , a STI embedded in the semiconductor substrate 12 , a logic device (such as the aforementioned logic gate 40 ) at least partially overlapping the STI 24 , and two SONOS cells 42 , 44 disposed in the overlapped region of the logic gate 40 and the STI 24 .
The device also includes a U-shaped nitride liner 22 disposed in the STI 24 , a boron doped nitride layer 32 connected to one tip of the U-shaped nitride liner 22 , and a phosphorus doped nitride layer 34 connected to the other tip of the U-shaped nitride liner 22 . A U-shaped oxide liner 20 is disposed preferably between the substrate 12 and the U-shaped nitride liner 22 , the boron doped nitride liner 32 , and the phosphorus doped nitride liner 34 .
The two mini-SONOS cells 42 , 44 are preferably formed at the corners of the STI 24 , such as in the region where the STI 24 , the boron doped or phosphorus doped nitride layer, and the U-shaped oxide liner 20 are sandwiched. In this embodiment, the first mini-SONOS cell 42 includes a portion of the polysilicon layer 38 , a portion of the gate oxide layer 36 , the STI 24 , the boron doped nitride layer 32 , the U-shaped oxide liner 20 , and the semiconductor substrate 12 . The second mini-SONOS cell 44 formed at the other corner of the STI 24 opposite to the first mini-SONOS cell 42 preferably includes a portion of the polysilicon layer 38 , a portion of the gate oxide layer 36 , the STI 24 , the phosphorus doped nitride layer 34 , the U-shaped oxide liner 20 , and the semiconductor substrate 12 .
As two mini-SONOS cells are accomplished at the overlapping region between the logic gate and the STI, the present invention could fine-tune the voltage of the mini-SONOS cells by adjusting the dosage of the boron or phosphorous doped within the doped nitride layers 32 , 34 of the two mini-SONOS cells 42 , 44 , which could then be used to adjust the threshold voltage (Vt) of the device and relieve the edge fringing effect found in conventional devices with logic gate.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | A method for fabricating a semiconductor device with mini-SONOS cell is disclosed. The method includes: providing a semiconductor substrate having a first MOS region and a second MOS region; forming a first trench in the semiconductor substrate between the first MOS region and the second MOS region; depositing a oxide liner and a nitride liner in the first trench; forming a STI in the first trench; removing a portion of the nitride liner for forming a second trench between the first MOS region of the semiconductor substrate and the STI and a third trench between the STI and the second MOS region of the semiconductor substrate; and forming a first conductive type nitride layer in the second trench. | 7 |
This application is a divisional of U.S. Ser. No. 08/163,017 filed Dec. 7, 1993, now, which is a divisional of U.S. Ser. No. 07/898,253 filed Jun. 15, 1992, now U.S. Pat. No. 5,321,153 issued Jun. 14, 1994.
BACKGROUND OF THE INVENTION
The present Invention relates to catalytic asymmetric hydrogenation of olefins to synthesize chiral alpha-amino phosphonates and selected novel chiral alpha-amino phosphonates. The chiral alpha-amino phosphonates are either useful as biocides, antibiotics and/or useful in the preparation of phosphorous-containing analogs of peptides, i.e., phosphoric peptides or pseudopeptides having known uses. For example, such phosphorus-type compounds have been shown to be effective as antibiotics, antibiotic enhancers, or enzyme Inhibitors.
In the past desired stereoisomers have been difficult to obtain. Laborious and expensive processes such as those using fractional crystallization and recycle loops have been common in procedures involving a resolution step to obtain a desired stereoisomer. More recently some olefins have been subjected to asymmetric hydrogenation over rhodium and other metal coordination catalysts having optically active ligands.
Such asymmetric hydrogenation for the preparation of selected enantiomers is shown by the following references:
U.S. Pat. No. 4,939,288;
U.S. Pat. No. 4,277,420;
East German Application Nos. 280,527; 280,528; 280,529; 240,372 described in corresponding Derwent Abstract Numbers 90-362220/49, 90-362221/49, 90-362222/49, 87-057083/09, respectively;
Int. J. Peptide Protein Res. 41, 1988, 269-280;
U.S. Pat. No. 4,912,221;
EP Application No. 90307750.1;
U.S. Pat. No. 4,906,773;
U.S. Pat. No. 4,916,252;
U.S. Pat. No. 4,316,847;
EP Application No. 89403599.7;
Japanese Number 3002152A described in WPI Acc No. 91-048825;
German Appl. No. 140-036 described in Derwent Abstract No. 34661C/20.
Some (1-Aminoalkyl)phosphonic acids, the phosphonic acid analogs of amino acids, and particularly the selected enantioselective synthesis of optically pure aminophosphonic acids and phosphonopeptides have been prepared by resolution and by asymmetric synthesis using chiral auxiliaries. This is exemplified by the following references:
Schollkoph et al, Liebigs Ann. Chem., 1985, 555-559;
Aboujaoude et al, Phosphorus Sulfur, 1983, 18(1-2-3), pp. 133-6;
Bissane et al, Pept. 1990 Proc. Eur. Pept. Symp. 21st, Meeting Date 1990, pp. 438-9,
Glowak et al, Khim. Primen. Fosfororg, Soedin., Tr. Yubileinol Kong., 6th Meeting Date 1977, 1981, pp.2251-3;
Ornstein, J. Org. Chem., 1989, 54(9), pp. 2251-2;
Sauveur et al, Phosphorus Sulfur, 1983, 14(3), pp.341-6;
Growiak and Sawka-Dobrowolska, Tetrahedron Letters, 1977, No. 45, pp. 3965-8; and
Parsons et al, J. Med. Chem. 1988, No. 31, pp. 1772-8.
Schollkoph et al report that "attempts to hydrogenate 3a" (which is N-[1-(dimethoxyphosphoryl)ethenyl]formamide) at room temperature, normal pressure) in the presence of (R,R)-DIPAMP failed." Schollkoph et al disclose the reduction of certain dehydro alpha-amino phosphonates by catalytic asymmetric hydrogenation in the presence of rhodium (+) DIOP catalyst. Thus, surprisingly, both the chemical yield and the asymmetric induction providing enantiomeric enhancements (ee) of the present invention process provide essentially pure compounds of a particular stereoisomeric form including selected chiral compounds new essentially pure not previously known. Further, Genet et al, Tetrahedron letters, 1986, Vol. 27, No. 38, pp 4573-76, provide comparisons of DIOP and DIPAMP in a different asymmetric allylation consistent with Schollkoph.
Reported diastereomeric mixtures of 1-aminoalkylphosphono type compounds are found in numerous references of which the following are examples:
Baylis et al, J. Chem. Soc. Perkin Trans I 1984., 1984,2845-53;
Yuan and Qi, Synthesis, 1988, June, 472-4 disclose 1-amino-substituted benzyl phosphonic acids where the benzyl includes various substituents.
U.S. Pat. No. 4,016,148 discloses peptide derivatives having a moiety characterized by the replacement of the carboxyl group of a naturally occurring L alpha-amino acid by a phosphorus group including a --P(O)(OH) 2 group.
Recent reviews disclosing the preparation of selected diastereomeric and chiral alpha-amino phosphonates are found in the following references respectively:
Kukhar and Sclodenko, Russ. Chem. Rev., 1987, pp. 1504-32; and
Dhawan and Redmore, Phosphorus and Sulfur, 1987, 32, pp. 119-44.
The following additional references disclose various specific chiral alpha-amino phosphonates:
Sawamura et al, Tetrahedron Letters, 1989, Vol. 30, No. 17, pp 2247-50;
Sting and Steglich, Synthesis, 1990, February, pp. 132-4;
Solodenko et al, Tetrahedron, 1991, Vol. 47, No. 24, pp. 3989-98;
Kafarski and Lejczak, Can. J. Chem. 1983, 61, pp. 2425-30;
Atherton et al, Antimicrobial Agents and Chemotherapy, 1979, May, pp. 877-83;
Atherton et at, J. Med. Chem., 1986, 29, pp. 29-40;
Scholkoph and Schutze, Liebigs Ann. Chem., 1987, pp. 45-9;
Bartlett and Lamden, Bioorganic Chemistry, 1986, 14, pp. 356-77;
Huber and Vasella, Helvetica Chimica Acta, 1987, 70, pp. 1461-76.
The interesting biological properties of α-aminophosphonates make them attractive analogues of α-aminoacids, [(a) Redmore, D. Top. Phosphorus Chem., 1976, 8, 515; (b) Petrov, K. A.; Chauzov, V. A.; Erokhina, T. S. Russ. Chem. Rev. 1974, 43, 984; (c) Kafarski, P.; Mastarlerz, P. Aminophosphonates: Natural Occurance, Biochemistry and Biological Properties, Bertrage zur Wirkstofforschung, Ak. Ind. Kompl. DDR, 1984, 21.] While they resemble their carbon counterparts, the tetrahedral phosphorus also allows them to function as transition state analogues. These pharmaceutically-interesting compounds [Certain phosphorus analogues of α-amino phosphonates are being investigated by the pharmaceutical industry as antibiotics, see; (a) Atherton, F. R.; Hall, M. J.; Hassall, C. H.; Lambert, R. W.; Llod, W. J.; Ringrose, P. S. Antimicrob. Agents Chemother., 1979, 15, 696; (b) Chakravarty, P. K.; Greenlee, W. J.; Parsons, N. H.; Patchett, A. A.; Combs, P.; Roth, A.; Busch, R. D.; Mellin, T. N. J. Med. Chem., 1989, 32, 1886 and references therein.] have been synthesized by various racemic routes, but the need to develop a practical asymmetric method still exists. The present invention now successfully fulfills this need.
α-Amino phosphonates have recently been reported to serve as starting materials for the preparation of potent inhibitors of HIV-1 protease. (Dreyer, G. B. New diamino phosphinic acid derivatives are aspartic protease inhibitors used to treat viral infections especially HIV type 1. Patent Application W09900954-A1, Jan. 22, 1992, assigned to SmithKline Beecham Corp.) This application is incorporated herein by reference to provide the basis for utility for the present invention process and its intermediates. Since the α-amino phosphonate employed by Dreyer et al was racemic (Dreyer, G. B.; Choi, J. K.; Meek, T. D.; Tomaszek, T. A., Jr. 203rd American Chemical Society Meeting, San Francisco, Calif. Apr. 5-10, 1992, Medicinal Chemistry #179), the inhibitor was made as a mixture of isomers necessitating a tedious chromatographic separation in order to isolate the most active constituent. The most active isomer was derived from the phosphorus analogue of phenylalanine with the L(R) absolute configuration. Not only would the methodology described herein be adaptable to the preparation of the most active isomer of the SKB HIV-protease inhibitor, but to a wide variety of analogues as well. Intermediates of U.S. Pat. No. 4,946,833 and each of European Application Nos. 89401595.7 and 90402226.6 are related to the novel compound I of the present invention. German Application 4029444A abstracted in Derwent Abstract No. 91-095191/14 discloses compounds for regulating plant growth related to the novel compounds of Formula II of the present invention. Further, EP 207,890A disclosed in Derwent Abstract No. 87-001565/01 includes 1-amino-2-phenylethylphosphorus acid derivatives as microbiocidal and biocidal agents.
The flexibility of the present synthesis permits the synthesis of very unique analogues of α-amino phosphonates that are related to known compounds having biological properties relative to molecules available by more demanding syntheses. The literature is replete with examples of novel amino acid side chains designed to impart improved biological properties to analogous molecules.
BRIEF SUMMARY OF THE INVENTION
The present invention is a novel compound of the formula (I') ##STR1## wherein R 1 ' is (1) cyclopentyl, cyclopentylmethyl, cyclohexyl, or cyclohexylmethyl;
(2) alkyl of from one to six carbons substituted by one or two hydroxyl, chloro, or fluoro;
(3) phenyl substituted by one to three substituent(s) consisting of
(a) halogen consisting of fluoro, chloro, bromo, iodo,
(b) alkoxy of from one to three carbons,
(c) nitro,
(d) amido,
(e) mono- or di- alkyl (of from one to four carbons) amido;
(f) hydroxy with the proviso that when the substituent is one or two hydroxy then one of hydroxy can not be in the position para to the phenyl bond,
(4) tolyl;
(5) tolyl substituted by one to three substituents consisting of
(a) alkyl of from one to four carbons,
(b) halogen consisting of fluoro, chloro, bromo, iodo,
(c) alkoxy of from one to three carbons,
(d) nitro,
(e) amido,
(f) mono- or di- alkyl (of from one to four carbons) amido;
(g) hydroxy;
(6) naphthyl optionally attached through a CH 2 group and optionally substituted by one to three substituents consisting of
(a) alkyl of from one to four carbons,
(b) halogen consisting of fluoro, chloro, bromo or iodo,
(c) alkoxy of from one to three carbons,
(d) nitro,
(e) amido,
(f) mono- or di- alkyl (of from one to four carbons) amido,
(g) hydroxy; or
(7) indol-3-yl, indol-2-yl, or imidazol-4-yl, or indol-3-ylmethyl, indol-2-ylmethyl or imidazol-4-ylmethyl;
(8) NHA wherein A is
(a) trityl,
(b) hydrogen,
(c) alkyl of from one to six carbons,
(d) R 10 CO wherein R 10 is (A)hydrogen, (B) alkyl of from one to three carbons optionally substituted with hydroxyl, chloro, or fluoro, (C) phenyl or naphthyl; unsubstituted or substituted with one to three of (i) alkyl of from one to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons, or (D) a 5 to 7 member heterocycle such as indolyl, pyridyl, furyl or benzisoxazolyl;
(e) phthaloyl wherein the aromatic ring is optionally substituted by one to three of (A) alkyl of from to three carbons, (B) halogen where halogen is F, Cl, Br, or I, (C) hydroxy, (D) nitro, (E) alkoxy of from one to three carbons, (F) CON(R 11 ) 2 wherein R 11 independently hydrogen or alkyl of from one to four carbons,
(f) R 12 (R 13 R 14 C) m CO wherein m is one to three and R 12 , R 13 , and R 14 are independently (A) hydrogen, (B) chloro or fluoro, (C) alkyl of from one to three carbons optionally substituted by chloro, fluoro, or hydroxy, (D) hydroxy, (E) phenyl or naphthyl optionally substituted by one to three of (i) alkyl of from to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons, (F) alkoxy of from one to three carbons, (G) 5 to 7 member heterocycle such as indolyl, pyridyl, furyl, or benzisoxazolyl, or (H) R 12 , R 13 , and R 14 are independently joined to form a monocyclic, bicyclic, or tricyclic ring system each ring of which is a cycloalkyl of from three to six carbons; except that only one of R 12 , R 13 and R 14 can be hydroxy or alkoxy on the same carbon and can not be hydroxy, chloro or fluoro when m is one;
(g) R 12 (R 13 R 14 C) m W wherein m is independently 1 to 3 and W is OCO or SO 2 and R 12 , R 13 , and R 14 are independently as defined above;
(h) R 20 W wherein R 20 is a 5 to 7 member heterocycle such as indolyl, pyridyl, furyl, or benzisoxazolyl;
(i) R 21 W wherein R 21 is phenyl or naphthyl; unsubstituted or substituted by one to three substituents or (i) alkyl of from one to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons;
(j) R 12 (R 13 R 14 C) m P(O)(OR 22 ) wherein R 22 is alkyl of from one to four carbons or phenyl and R 12 , R 13 and R 14 are independently as defined above;
(k) R 20 P(O)(OR 22 ) wherein R 20 and R 22 are as defined above;
(l) R 21 P(O)(OR 22 ) wherein R 21 and R 22 are as defined above;
(9) R 12 (R 13 R 14 C) m V wherein V is 0 or NH and R 12 , R 13 and R 14 are independently as defined above;
(10) N(R 11 ) 2 wherein R 11 is independently as defined above;
(11) NR 15 NR 16 wherein R 15 and R 16 are joined to form a 4 to 6 membered saturated nitrogen containing heterocycle which is (i) azetidinyl, (ii) pyrrolidinyl, (iii) piperidinyl, or (iv) morpholinyl;
(12) R 17 OCH 2 O wherein R 17 is
(a) alkyl of from one to six carbons,
(b) R 21 wherein R 21 is independently defined as above; or
(c) CH 2 Q 1 wherein Q 1 is phenyl, naphthyl or a 5 to 7 membered heterocycle independently as defined above;
(13) R 17 OCH 2 CH 2 OCH 2 wherein R 7 is independently as defined above;
(14) alkynyl of from two to six carbons optionally substituted with R 21 where in R 21 is independently as defined above;
(15) alkenyl of from two to six carbons optionally substituted with R 21 where in R 21 is independently as defined above;
R 2 and R 5 are independently hydrogen, alkyl, lower cycloalkyl, or ar wherein ar is an aromatic group, preferably unsubstituted or substituted phenyl;
R 3 ' is hydrogen, an amino acid radical or a protecting group such as a substituted or unsubstituted acyl; and
R 4 is hydrogen and with the proviso that when R 3 ' is hydrogen, then R 1 ' cannot be (1) alkyl substituted by hydroxy, (2) phenyl substituted by halogen, hydroxy or alkoxy, (3) 2-indolyl, (4) 4-imidazolyl, or (5) alkoxycarbonyl.
The present invention is also a compound of the formula (II) ##STR2## wherein R 1 , R 2 , R 3 , R 4 and R 5 are all as defined herein.
The present invention is also a process comprising the treatment of a compound of the formula (II) ##STR3## wherein R 1 is (1) hydrogen;
(2) alkyl of from 1 to 6 carbons optionally substituted by one or two hydroxyl, chloro or fluoro;
(3) cycloalkyl of from 3 to 7 ring carbons;
(4) ar 4 which is a group such as phenyl, or phenyl substituted by one to three substituent(s) consisting of
(a) alkyl of from one to four carbons,
(b) halogen consisting of fluoro, chloro, bromo, iodo,
(c) alkoxy of from one to three carbons,
(d) nitro,
(e) amido,
(f) mono- or di- alkyl (of from one to four carbons) amido;
(g) hydroxy;
(5) ar 5 which is a group such as tolyl;
(6) ar 6 which is a group such as tolyl substituted by one to three substituents consisting of
(a) alkyl of from one to four carbons,
(b) halogen consisting of fluoro, chloro, bromo, iodo,
(c) alkoxy of from one to three carbons,
(d) nitro,
(e) amido,
(f) mono- or di- alkyl (of from one to four carbons) amido,
(g) hydroxy;
(7) ar 7 which is a group optionally attached through a CH 2 and is naphthyl or naphthyl substituted by one to three substituents consisting of
(a) alkyl of from one to four carbons,
(b) halogen consisting of fluoro, chloro, bromo, iodo,
(c) alkoxy of from one to three carbons,
(d) nitro,
(e) amido,
(f) mono- or di- alkyl (of from one to four carbons) amido,
(g) hydroxy; or
(8) ar 8 which is a group such as indol-3-yl, indol-2-yl, or imidazoly-4-yl or indol-3-ylmethyl, indol-2-ylmethyl or imidazol-4-ylmethyl (preferably unsubstituted or substituted phenyl or indol-3-yl);
(9) NHA wherein A is
(a) trityl,
(b) hydrogen,
(c) alkyl of from one to six carbons,
(d) R 10 CO wherein R 10 is (A)hydrogen, (B) alkyl of from one be six carbons optionally substituted with hydroxyl, chloro, or fluoro, (C) phenyl or naphthyl unsubstituted or substituted with one to three of (i) alkyl of from one to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons, or (D) a 5 to 7 member heterocycle such as indolyl, pyridyl, furyl or benzisoxazolyl;
(e) phthaloyl wherein the aromatic ring is optionally substituted by one to three of (A) alkyl of from one to three carbons, (B) halogen where halogen is F, Cl, Br, or I, (C) hydroxy, (D) nitro, (E) alkoxy of from one to three carbons, (F) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons,
(f) R 12 (R 13 R 14 C) m CO wherein m is one to three and R 12 , R 13 , and R 14 are independently (A) hydrogen, (B) chloro or fluoro, (C) alkyl of from one to three carbons optionally substituted by chloro, fluoro, or hydroxy, (D) hydroxy, (E) phenyl or naphthyl optionally substituted by one to three of (i) alkyl of from to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons, (F) alkoxy of from one to three carbons, (G) 5 to 7 member heterocycle such as indolyl, pyridyl, furyl, or benzisoxazolyl, or (H) R 12 , R 13 , and R 14 are independently joined to form a monocyclic, bicyclic, or tricycle ring system each ring of which is a cycloalkyl of from three to six carbons; except that only one of R 12 , R 13 and R 14 can be hydroxy or alkoxy on the same carbon and can not be hydroxy, chloro or fluoro when m is one;
(g) R 12 (R 13 R 14 C) m W wherein m is independently 1 to 3 and W is OCO or SO 2 and R 12 , R 13 , and R 14 are independently as defined above;
(h) R 20 W wherein R 20 is a 5 to 7 member heterocycle such as pyridyl, furyl, or benzisoxazolyl;
(i) R 21 W wherein R 21 is phenyl or naphthyl; unsubstituted or substituted by one to three substituents of (i) alkyl of from one to three carbons, (ii) halogen where halogen is F, Cl, Br, or I, (iii) hydroxy, (iv) nitro, (v) alkoxy of from one to three carbons, (vi) CON(R 11 ) 2 wherein R 11 is independently hydrogen or alkyl of from one to four carbons;
(j) R 12 (R 13 R 14 C) m P(O)(OR 22 ) wherein R 22 is alkyl of from one to four carbons or phenyl and R 12 , R 13 and R 14 are independently as defined above;
(k) R 20 P(O)(OR 22 ) wherein R 20 and R 22 are as defined above;
(l) R 21 P(O)(OR 22 ) wherein R 21 and R 22 are as defined above;
(10) R 12 (R 13 R 14 C) m V wherein V is 0 or NH and R 12 , R 13 and R 14 are independently as defined above;
(11) N(R 11 ) 2 wherein R 11 is independently as defined above;
(12) NR 15 NR 16 wherein R 15 and R 16 are joined to form a 4 to 6 membered saturated nitrogen containing heterocycle which is (i) azetidinyl, (ii) pyrrolidinyl, (iii) piperidinyl, or (iv) morpholinyl;
(13) R 17 OCH 2 O wherein R 17 is
(a) alkyl of from one to six carbons,
(b) R 21 wherein R 21 is independently defined as above; or
(c) CH 2 Q 1 wherein Q 1 is phenyl, naphthyl or a 5 to 7 membered heterocycle as defined above;
(14) R 17 OCH 2 CH 2 OCH 2 wherein R 17 is independently as defined above;
(15) alkynyl of from two to six carbons optionally substituted with R 21 where in R 21 is independently as defined above;
(16) alkenyl of from two to six carbons optionally substituted with R 21 where in R 21 is independently as defined above;
R 2 and R 5 are independently hydrogen, alkyl, lower cycloalkyl, or an aromatic group, preferably unsubstituted or substituted phenyl;
R 3 is a protecting group such as a substituted or unsubstituted acyl; and
R 4 is hydrogen or lower cycloalkyl; with the overall proviso that one of R 1 and R 4 must be hydrogen;
with hydrogen in the presence of rhodium (R,R)-(1,2-ethanediyl bis[(orthomethoxyphenyl)phenylphosphine] (H 2 RhDiPAMP) in a deoxygenated solvent; optionally (1) deprotecting the nitrogen or (2) deprotecting the nitrogen and further treating to add an amino acid radical to the nitrogen, to obtain a compound of the formula (I) ##STR4## wherein R 1 , R 2 , R 4 and R 5 is as defined above; and R 3 ' is hydrogen, amino acid radical or a protecting group.
The present invention is also the process comprising the condensation of a compound of the formula (III) ##STR5## wherein R 1 is as defined above with a compound of the formula (IV) ##STR6## wherein R 5 is as defined and R 8 is a protecting group; in the presence of titanium tetrachloride; to obtain a compound of the formula (V and VA) ##STR7## and then V and VA are treated with a solution of trifluoroacetic acid in an inert solvent such as methylene chloride in the presence of molecular sieves to obtain the mixture of the formula (VI and VIA) ##STR8## which is treated with diphenylphosphoryl azide at about 0° C., extracted and warmed to effect Curtius rearrangement; and treated with an alcohol, such as para-methoxybenzyl alcohol, tert-butyl alcohol or benzyl alcohol or the like, to trap the incipient isocyanate and to obtain compound of the formula (II) ##STR9## wherein R 1 , R 2 , R 3 , R 4 and R 5 are as defined above.
Optionally this immediately preceding process to obtain the compound II may also include a further step wherein the compound of formula II is further treated with hydrogen in the presence of rhodium (R,R)-(1,2-ethanediyl bis[(orthomethoxyphenyl)phenylphosphine] in a deoxygenated solvent; and optionally (1) treated to deprotect the nitrogen, (2) and to add an amino acid radical on the nitrogen to obtain a compound of the formula (I) ##STR10## wherein R 1 , R 2 , R 3 ', R 4 , and R 5 is as defined above.
The preferred process is for the preparation of the phosphorus analog of L-phenylalanine.
DETAILED DESCRIPTION OF THE INVENTION
The terms in the present invention generally have the following meaning.
Alkyl means an alkyl of from one to six carbons such as methyl, ethyl, propyl and the like and isomers thereof.
An aromatic group means a phenyl, substituted phenyl, tolyl, substituted tolyl, naphthyl, indol-3-yl, indol-2-yl, a 5 to 7 membered heterocycle group such as pyridyl, furyl, or benzisoxazolyl and the like. The latter heterocyclic group is usually attached through one of the carbon atoms of the ring.
Substituted phenyl and substituted tolyl means each of phenyl or tolyl is substituted with from one to three substituents such as alkyl, carboxyl, hydroxyl (and base salts thereof), alkoxy, halogen, acyloxy, aryloxy, aralkoxy, amino, alkyl amido (both mono and di alkylamido), nitro, cyano or sulfonyl.
Acyl means such groups as acetyl, benzoyl, formyl, propionyl, butyryl, toluyl, and may include substituted such groups, for example nitrobenzoyl, and the like; and may also include groups composing urethano groups with the nitrogen, such as carbalkoxy groups, for example, carbethoxy, and the like or other acyl variants commonly used as blocking groups in peptide synthesis. In other words the blocking groups in the present invention are commonly acyl groups.
Lower cycloalkyl means cyclic hydrocarbon groups containing 3 to 6 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl.
The compounds and the processes of the present invention include an asymmetric carbon adjacent to the carbon on which the nitrogen and phosphorus group are attached. In the compound of the formula I or of the compound of the formula I' the stereo configuration of this carbon is the same as the carbon in an analogous naturally occurring peptide configuration and is essentially optically pure. In other words the present invention provides a novel synthesis for obtaining optically pure compounds and selected novel optically pure compounds of the synthesis corresponding to an analogous naturally occurring peptide.
Consequently, an ordinarily skilled artisan can determine pharmacological activity for selected compounds within the formula I' and also ascertain the usual and customary dosage forms or dosages by the use of analogous means as applied to the naturally occurring peptide.
Likewise use of the compounds of the formula I as intermediates in the preparation of compound which are derivatives of the compounds of formula I are also within the skill of the ordinary artisan.
The compounds of the invention may contain other isomeric moieties within its substituents. Thus, the invention includes the individual isomers and mixtures thereof. The individual isomers of this type may be prepared or isolated by methods known in the art.
Chiral means optically active.
The compounds of Formula I' which manifest pharmacologically activity are useful both in the free base and the free acid form or in the form of base salts thereof, as well as, in the form of acid addition salts. All forms are within the scope of the invention. In practice, use of the salt form amounts to use of the free acid or free base form. Appropriate pharmaceutically acceptable salts within the scope of the invention are those derived from mineral and organic acids or those derived from bases such as suitable organic and inorganic bases. For example, see "Pharmaceutical Salts", J. Pharm. Sci., 66(1), 1-19(1977). The acid addition salts of said compounds are prepared either by dissolving the free base of compound I' in aqueous or aqueous alcohol solution or other suitable solvents containing the appropriate acid or base and isolating the salt by evaporating the solution, or by reacting the free base of Compound I" having an acid group thereon with a base such that the reactants are in an organic solvent, in which case the salt separates directly or can be obtained by concentration of the solution.
The base salts of compounds of Formula I described above are prepared by reacting the appropriate base with a stoichiometric equivalent of the acid compounds of Formula I to obtain pharmacologically acceptable base salts thereof.
Specifically, the present invention is a process as shown in Scheme 1.
The process of Scheme 1 may generally be carried out at from about 1 to 100 psig and at a temperature from about 0° C. to 60° C., preferably at about room temperature and at a pressure about 40 psig, in inert solvents such as methanol, ethanol, tetrahydrofuran, dichloromethane, acetonitrile and the like or mixtures thereof. ##STR11##
Evaluation of the results may be accomplished by standard methods, such as vapor phase chromatography on a chiral capillary column, or by HPLC (high performance liquid chromatography) on a chiral column or by evaluation of the optical rotation of a solution of the compound.
More particularly the process of Scheme 1 may be accomplished be the following general procedure.
A Fisher-Porter bottle is charged with the appropriate substrate II dissolved in deoxygenated methanol along with 0.1-1.0 mol percent rhodium (R,R)-DiPAMP (R,R)-(1,2-ethanediyl bis[(o-methoxyphenyl)phenylphosphine]. After 5 nitrogen purges (40 psig) the solution was purged 5 times with hydrogen (40 psig) and then allowed to hydrogenate at room temperature for 1-24 h. The hydrogen was replaced with nitrogen and the contents of the bottle concentrated in vacuo. The catalyst residue was separated from the chiral alpha-amino phosphonate I by dissolving the product in iso-octane. The catalyst residue is not soluble in iso-octane.
A general procedure for the hydrolysis of chiral N,O-protected alpha-amino phosphonates of the formula I wherein R 3 ' is a protecting group is as follows. A sample of the chiral N,O-protected alpha-amino phosphonate derivative is refluxed for 24 h with 12N hydrochloric acid. The solvent is removed in vacuo. The residue is taken up in water and re-concentrated in vacuo. After thoroughly drying under vacuum the hydrochloride salt is converted to the free amine by treatment with excess propylene oxide. The precipitated amino acid is then isolated by filtration and optionally recrystallized from water/methanol.
An evaluation is made of optical purity by chiral vapor phase chromatography. The N,O-protected chiral alpha-amino phosphonate derivatives are analyzed by chiral gas chromatography for optical purity. A solution of the racemic amino acid derivative in dichloromethane is separated into the two enantiomers by a 25 meter Chirasil Val III capillary column with flame ionization detection. After conditions for separation of the two enantiomers are established, each chiral hydrogenation product is evaluated for the extent of optical purity.
Specifically, when R 1 is hydrogen and R 3 is C 6 H 5 CH 2 OCO in the above described hydrogenation of the compound of the formula II at 40 psig in methanol at room temperature gives the product of the formula I wherein R 1 is hydrogen and R 2 is C 6 H 5 CH 2 OCO in a yield of 98% after two hours and evaluation of the optical purity of the compound of the formula I by vapor phase chromatography on a chiral capillary column revealed that the L-isomer was formed to the extent of 95% purity.
Variations in these conditions and evaluations for different compounds within the definitions of the formula I are within the skill of an ordinarily skilled artisan.
The compounds of the formula II are known or can be prepared from compounds that are known by methods known in the art or for compounds of the above formula II can be prepared by the following methods. ##STR12##
Condensation of the compound of the formula III with the compound of the formula IV in the presence of titanium tetrachloride gives the expected Knovenagel, (Lehnert, W., Tet. Lett., 1970 pp. 4723-4; Lehnert, W., tetrahedron, 1973, 29, pp. 635-8), product along with the aldol condensation product in good yield (V and VA). Treatment of this mixture with a solution of trifluoroacetic acid in methylene chloride in the presence of molecular sieves results in dehydration and the formation of a 3:1 mixture of Z:E isomers (VI and VIA). Treatment of this mixture with diphenylphosphoryl azide at about 0° C. followed by extractive work-up gives the corresponding acyl azide. The acyl azide is then diluted with toluene and warmed to 90° C. to effect Curtius rearrangement. The incipient isocyanate is then trapped in situ with benzyl alcohol to produce the corresponding N-protected dehydro alpha-amino phosphonate of the formula II as a single (E) geometrical isomer. ##STR13##
More particularly these processes may be accomplished by the following general procedures.
A general procedure for the Knovenagel condensation of tert-butyl O,O-dimethylphosphono acetate IV with aldehydes III is as follows. A 3-necked round bottomed flask is fitted with a nitrogen inlet, provisions for magnetic or mechanical stirring and a serum cap. The flask is then charged with anhyd. tetrahydrofuran (THF) and the solution is cooled to 0° C. in an ice/salt bath. Titanium tetrachloride (2 equivalents per aldehyde) is dissolved in carbontetrachloride and added dropwise to the THF solution. A solution of the appropriate aldehyde (1 equivalent) III in a small amount of THF is then added to the above solution followed by a solution of tert-butyl O,O-dimethylphosphono acetate (1 equivalent) IV in THF. Finally, N-methylmorpholine (4 equivalent) is added slowly to this stirring solution, after the addition is complete the solution is allowed to warm to room temperature and stirred for 24 h. The solution is then cooled to about 0° C. and treated with water dropwise over a few minutes. The solution is diluted with ether, poured into a separatory funnel and the aqueous phase extracted with ether 3 times. The combined ethereal solution is washed with NaHCO 3 , brine, dried over anhyd. MgSO 4 , filtered and concentrated in vacuo. The crude product, V and VA, is then purified by flash chromatography.
The general procedure for removal of a protecting group, such as the tert-butyl ester is as follows. A sample of the Knovenagel product, V and VA, is dissolved in dichloromethane and treated with an equal (volume) amount of trifluoroacetic acid at 0° C. The solution is allowed to warm to room temperature and the progress of the reaction monitored by TLC. When the reaction is finished the solvents are removed in vacuo and the residue purified by crystallization or flash chromatography on silica gel. This procedure produces the (Z) and (E)-2-substituted 1-carboxy-1-dimethoxyphosphono ethylene derivatives, VI and VIA.
Curtius rearrangement of [E,-2-substituted 1-carboxy-1-dimethoxyphosphono ethylene derivatives:
Preparation of dehydro alpha-amino phosphonates is as follows. The (Z) and (E)-2-substituted 1-carboxy-1-dimethoxyphosphonc ethylene derivatives, VI and VIA, and 1 equivalent of triethylamine is dissolved in dichloromethane and then treated with diphenylphosphoryl azide at 0° C. for a period of 1 h. The solution is then poured into a separatory funnel and washed with 1N KHSO 4 , sat. aq. NaHCO 3 , dried over anhyd. MgSO 4 , filtered and concentrated in vacuo. The acyl azide thus produced is diluted with toluene and warmed to 90° C. for ca. 1 h to effect Curtius rearrangement. This solution is then treated with a mixture of triethylamine (1.5 equivalents) and benzyl alcohol (1.05 equivalents) and allowed to stir at 90° C. for an additional 1 h. The contents of the flask are then poured into a separatory funnel and washed with 1N KHSO 4 , sat. aq. NaHCO 3 , brine, dried over anhyd. MgSO 4 , filtered and concentrated in vacuo to give the desired dehydro alpha-amino acid, II, which was purified by flash chromatography over silica gel.
Variations in these conditions and evaluations for different compounds within the definitions of the formula are within the skill of an ordinarily skilled artisan. For example, substituents may include groups also recognized as requiring protective groups and, of course, these are readily prepared and removed as needed.
The compounds of the formula III and IV are known or can be prepared from compounds that are known by methods known in the art.
The catalytic asymmetric hydrogenation as described above for Scheme I is carried out on the dehydro alpha-amino phosphonate of the formula II in the presence of rhodium (R,R)-DiPAMP to produce the desired compound of the formula I.
When the appropriate corresponding starting materials are used the L-alpha-amino phosphonate analogue of phenylalanine is obtained in excellent yield with very high optical purity. The enantiomeric excess of this latter named reaction is found to be greater than 98%.
The following examples illustrate of the present invention processes using compounds of the above described processes. Various other compounds within the processes of the present invention are readily prepared by these or variations of these examples. That is, the following examples are not meant to be limiting.
EXAMPLE 1
Aminomethylenebis(phosphonic acid)
Formamide (54 g, 1.2 mol) is added dropwise to a solution of phosphorus acid (100 g, 1.2 mol) and phosphorus trichloride (500 g, 3.6 mol). The solution is warmed to 70° C. for 2 h and then diluted cautiously with 300 mL of water. The solution is then allowed to stand overnight and then concentrated on a rotary evaporator with the bath temperature at 90° C. Upon cooling, the solution solidifies and the product is isolated by filtration on a Buchner funnel. The filter cake is washed thoroughly with a mixture of methanol and water (1:1 v:v) and dried in vacuo to give 100 g, 44% of material with mp 255°-265° C.
N-[bis(Dimethoxyphosphoryl)methyl]formamide
A mixture of the aminomethylenebis(phosphonic acid) as prepared above (45 g, 0.39 mol), trimethyl orthoformate (230 g, 2.4 mol) and p-toluenesulfonic acid (2g) are diluted with 500 mL of dry dimethylformamide and stirred at 120° C. for 2 days or until an appropriate assay indicates the reaction is complete. The solution is then filtered and concentrated in vacuo to give a semisolid. This material is recrystallized from acetone to give 64 g, 60% of material, mp 95° C. N[1-(Dimethoxyphosphoryl-2-phenylethenyl]formamide
A solution of N-[bis(dimethoxyphosphoryl)methyl]formamide (3.50 g, 12.7 mmol) is dissolved in 20 mL of dry methanol and treated with a solution of sodium methoxide (from 14 mmol of sodium metal) in methanol under nitrogen. The mixture is stirred at room temperature for 30 m and then treated with a solution of benzaldehyde (1.35 g, 12.7 mmol) in 5 mL of methanol. The solution is stirred at room temperature for 24 h and then concentrated in vacuo. The residue is extracted 3× with dichloromethane, the combined extracts dried over anhyd. MgSO 4 , filtered, and concentrated in vacuo to give an oil that is purified by radial chromatography over silica gel eluting with dichloromethane to 10% methanol in dichloromethane. The appropriate fractions are combined and concentrated to give 2.31 g, 76% of the desired product as an oil.
Asymmetric hydrogenation of N-[1-{Dimethoxyphosphoryl)-2-phenylethenylformamide: Preparation of N-[1-(R)-(Dimethoxyphosphoryl)-2-phenylethenyl]formamide.
A solution of N-[1-(Dimethoxyphosphory)-2-phenylethenyl]formamide (2.31 g, 9.7 mmol) is dissolved in 30 mL of degassed methanol in a Fisher-Porter bottle is treated with rhodium (R,R)-DiPAMP (50 mg, 0.067 mmol). The solution is flushed with nitrogen 5× and then with hydrogen 5× and hydrogenated at 40 psig for 16 h. The solution is then concentrated in vacuo and the residue purified by radial chromatography on silica gel eluting with 5% methanol in dichloromethane to give 1.00 g, 83% of material that is taken on the next step.
Hydrolysis of N-[1-(Dimethoxyphosphory)-2-phenylethyl]formamide: Preparation 1(R)-amino-2-phenylethanephosphonic acid, (L-phosphono phenylalanine).
A solution of N-[1(R)-(Dimethoxyphosphoryl)-2-phenylethenyl]formamide (500 mg, 2.1 mmol) in 40 mL of 6N HCl is heated to reflux for 48 h and then concentrated in vacuo. The residue is dissolved in ethyl acetate and water and treated with 1 mL of propylene oxide. The phases are separated and the aqueous phase extracted with ethyl acetate 3×. The combined ethyl acetate solution is dried over anhydrous MgSO 4 , filtered, and concentrated to give 374 mg, 89% of a white solid, mp 264°-267° C., [α] D @25° C.=-46 (c=0.5, 2N NaOH). IR(KBr) 1951, 1516 cm -1 . High resolution mass spectrum, calc'd for C 8 H 12 O 3 NP: 202.0812. Found: 202.0633.
Knovenagel condensation of 4-benzyloxy benzyaldehyde with tert-butyl P,P-dimethylphosphonoacetate: Preparation of 1-tert-butyl-1-dimethylphosphonyl-(E]-3-(4-benzyloxyphenyl) propenoate. ##STR14##
Procedure: a 2-neck, 500-mL, round bottom flask equipped with a nitrogen inlet and pressure-equalizing addition funnel is charged with THF (50 mL) and cooled in an ice both. Titanium tetrachloride (8.48 g, d 1.730, 4.89 mL, 4.6 mmol) in CCl 4 (12 mL) is subsequently added dropwise via the addition funnel over 30 minutes resulting in the formation of a copious, yellow precipitate (TiCl 4 .2THF). The 4-benzyloxybenzaldehyde (4.73 g, 22.3 mmol) in THF (8 mL) is added next via syringe over 5-10 minutes followed by the t-butyl P,P-dimethylphosphonoacetate (5.00 g, d 1.137, 4.40 mL, 22.3 mmol). N-methylmorpholine (9.02 g, d 0.920, 9.81 mL, 89.2 mmol) in THF (15 mL) is finally added via the addition funnel. The mixture is permitted to stir at 0° C. for 5 h before quenching with water (25 mL). The product is isolated by extracting the reaction mixture several times with ether. The combined ether layer is washed with saturated sodium bicarbonate and brine before drying over anhydrous magnesium sulfate. Filtration and evaporation of the solvent in vacuo revealed the crude product which is recrystallized from CH 2 Cl 2 /iso-octane to give 6.0 grams of white crystals (64% yield). 1-tert-butyl-1-dimethyphosphonyl-(E)-3-(4-benzyloxyphenyl)propenoate.
1 H NMR: (CDCl 3 , 300 MHz) δ7.49 (m, 8H, aromatic and olefinic protons); 6.99 (d, J=8.9 Hz, 2H, p-subst. aromatic); 5.13 (s, 2H, benzyl CH 2 ); 3.84 (d, J=11.4 Hz, 2 sq. OCH 3 's split by P); 1.54 (s, 9H, t-butyl). 13 C NMR: (CDCl 3 , 75.6 MHz) a 160, 147.5, 147,136, 131, 129, 128, 127, 126.7, 126.4, 115, 82.7, 70.1, 52.9 and 52.8 (P-OCH]), 27.8. 31 P NMR: (CDCl 3 ) δ20.0. MS: (FAB) m/e (relative intensity) 425 [(M +Li)+, 5%], 369 [(M+Li--C 4 H 8 )+, 100%].
Selective deprotection of the tert-butyl ester: preparation of 1-dimethoxyphosphonyl (E)-3-(4-benzyloxyphenyl) propenoic acid and 1-dimethyoxyphosphonyl (Z)-3-(4-benzyloxyphenyl) propenoic acid.
Procedure: The starting ester (3.7 g, 8.8 mmol) is dissolved in anhydrous dichloromethane (18 mL) under N 2 . ##STR15##
Trifluoroacetic acid (6.0 g, d 1.480, 4.1 mL, 53 mmol) is subsequently added dropwise at room temperature via syringe. The resulting red solution is permitted to stir overnight at room temperature. The solvent is then removed under reduced pressure, and saturated sodium bicarbonate is added to the residue. The aqueous layer is extracted several times with ethyl acetate to remove unreacted starting material before acidifying with conc. HCl. The carboxylic acid is subsequently extracted into ethyl acetate, and the ethyl acetate layer is washed with brine before drying over anhydrous magnesium sulfate. Filtration and evaporation of the solvent in vacuo revealed a bright yellow solid (2.85 g, 90% yield) which is identified as a mixture of olefins by proton NMR; the two isomers were not separated.
1 H NMR for E-olefin: (CDCl 3 , 300 MHz) δ9.5 (br s, 1H, acid OH); 7.61 (overlapping pair of d's: J=8.8 Hz, 2H, p-subst. aromatic); 7.38 (m, 5H, aromatic); 6.98 (d, J=8.8 Hz, 2H, p-subst. aromatic); 5.10 (s, 2H, benzyl CH 2 ); 3.87 (d, J=11.4 Hz, 6H, 2 eq. OCH3's split by P).
1 H NMR for Z-olefin: (CDCl 3 , 300 MHz) δ9.5 (br s, 1H, acid OH); 8.91 (d, J=42.3 Hz, olefinic proton); 7.76 (d, J=8.9 Hz, p-subst. aromatic); 7.38 (m, 5H, aromatic); 7.05 (d, J=8.9 Hz, p-subst. aromatic); 5.18 (s, 2H, benzyl CH 2 ); 3.75 (d, J=11.8 Hz, 6H, 2 eq. OCH 3 's split by P).
Formation of acyl azide: Preparation of dimethyl 1-azidocarbonyl 2(E)-(4-benzyloxyphenyl)ethenephosphonate and dimethyl 1-azidocarbonyl 2(Z)-(4-benzyloxyphenyl) ethenephosphonate. ##STR16## Procedure: To an ice-cooled solution of the acid mixture (2.73 g, 7.53 mmol) in dry toluene (11 ML) under nitrogen is added triethylamine (0.762 g, d 0.726, 1.05 mL, 7.53 mmol) and diphenylphosphoryl azide (2.07 g, d 1.277, 1.62 mL, 7.53 mmol). The resulting solution is stirred for 4 h at room temperature. The acyl azide products are isolated by diluting the solution with cold water and extracting with ether. The organic layer is dried over anhydrous magnesium sulfate, filtered, and evaporated under reduced pressure to reveal the crude product mixture which is immediately taken onto the next step.
Curtius rearrangement of acyl azide: Preparation of dimethyl 1-benzyloxycarbonylamino 2(E)-(4-benzyloxyphenyl]ethene phosphonate. ##STR17## Procedure: The crude acyl azide mixture is redissolved in anhydrous toluene (11 mL), and the solution is heated to reflux under nitrogen. After heating for 1 h, benzyl alcohol (0.78 mL, 7.53 mmol) is added dropwise. The resulting mixture is permitted to stir overnight at reflux before diluting with ethyl acetate, washing with sat. NaHCO 3 (3 times), 1N HCl (2 times), and brine, and drying over anhydrous magnesium sulfate. Filtration and evaporation of the solvent in vacuo revealed an oil which is purified by flash column chromatography on silica gel initially using CH 2 Cl 2 until the phenol by-product eluted, then switching to 1% MeOH/CH 2 Cl 2 to elute the desired product (R f =0.33, 5% MeOH/CH 2 Cl 2 ). Recrystallization with CH 2 Cl 2 /iso-octane afforded a 56% yield of white crystals.
1 H NMR: (CDCl 3 , 300 MHz) δ7.52 (d, J=8.8 Hz, 2H, p-subst. aromatic); 7,37 (m, 11H, aromatic and 1 olefinic); 6.92 (d, J=8.8 Hz, 2H, p-subst. aromatic); 5.92 (br B, 1H, NH); 5.14 (s, 2H, benzyl CH 2 ); 5.11 (s, 2H, benzyl CH 2 ); 3.78 (d, J=11 Hz, 6H, 2 eq. OCH 3 's split by P).
13 C NMR: (CDCl 3 , 75.6 MHz) δ160, 140.7, 140.3, 132, 128.6, 128.5, 128.2, 128.1, 127, 126, 115, 70.0, 67.5, 52.9 (d).
MS: (FAB) m/e (relative intensity) 468 (MH+, 65% ); 359 (M+-PO(OMe) 2 , (45%). ##STR18## Asymmetric hydrogenation of dimethyl 1-benzyloxycarbonylamino 2(E)-4-benzyloxyphenyl) ethene phosphonate: preparation of dimethyl (1(R)-benzyloxycarbonylamnio 2-(4-benzyloxyphenyl) ethane phosphonate, (dimethyl N-Cbz-L-O-benzyl phosphonotyrosine).
Procedure: The starting material (700 mg, 1.5 mmol) and the rhodium (R, R) diPAMP catalyst (approximately 10-20 mg) are placed in a Fischer-Porter tube and flushed with nitrogen (5 times). Degassed methanol is subsequently added, and the tube is flushed 5 more times with nitrogen followed by 5 times with hydrogen before pressurizing to a final volume of 45 p.s.i. The reaction is then permitted to stir at room temperature for 48 h. Typically the chiral products are filtered through silica gel to remove the catalyst.
Preparation of dimethyl N-Cbz-L-phosphonoalanine ##STR19## Dimethyl Acetylphosphonate. Trimethyl phosphite (57.1 g, 0.46 mol) is added dropwise to an ice cold solution of acetyl chloride (36.2, 0.26 nol) at a rate that the internal temperature did not rise above 5° C. The ice bath is removed and the solution warmed to room temperature and then heated to 100° C. for 1 hour. The solution is then vacuum distilled through a 12-inch Vigeraux column to give 30.87 g, 44% of a clear liquid with bp 57°-60° C. at 0.5 mn. H and C nmr are consistent with the assigned structure. This procedure is adapted from the published method of McConnell, R. L., Coover, H. W.,Jr. J. Am. Chem. Soc., 1956, 78, 4450-4452. ##STR20## Preparation of Dimethyl 1-Benzyloxycarbonylamino-1-ethenephosphonate. Dehydrophosphonopeptide synthesis: Method A. A 250 mL round bottomed flask equipped with a reflux condenser is charged with dimethyl acetylphosphonate (15.2 g, 0.1 mol), benzyl carbamate (15.1 g, 0.1 mol) and 60 mL of dry toluene. The solution is then treated with 1 g of camphor sulfonic acid and then heated to reflux for 12 h. TLC on silica get eluting with 8:1 hexane:ethyl acetate shows the desired product is formed and had R f =0.14. The solution is concentrated and purified by chromatography on a Prep-500 instrument with two silica gel cartridges eluting With hexane and ethyl acetate. The appropriate fractions are combined and concentrated to give 9.58 g, 31% of pure product that slowly crystallized on standing, mp 50°-52° C. This is essentially the method published by Zon, J. Synthesis, 1981, 324.
Dehydrophpsphonopeptide synthesis: Method B. A solution of dimethyl acetylphosphonate (12.4 g, 0.081 mol), benzyl carbamate (12.33 g, 0.081 mol) and 260 mL of dry toluene is treated with phosphorus oxychloride (30.3 mL, 0.33 mol). The solution is then warmed to 70° C. for 1 h and then cooled to room temperature. The solution is then poured into a solution of sat. aq. NaHCO 3 ), the pH of the solution is maintained between 6.9 and 7.3 by the addition of additional solid NaHCO 3 . The phases are separated and the aqueous phase extracted with two 500 mL portions of ethyl acetate. The combined organic phase is dried with anhyd. MgSO 4 , filtered, and concentrated in vacuo to give an oil 19.0 g, which was purified by chromatography on a Prep-500 as described above to give the pure product 7.7 g, 30%. ##STR21## Asymmetric hydrogenation of N-Cbz-dehydrophosphonoalanine [Dimethyl 1(R)-Benzyloxycarbonylamino-1-ethanephosphonate): Preparation of N-Cbz-L-phosphonoalanine.
A Fischer-Porter bottle is charged with N-Cbz-dehydrophosphonoalanine (5.00 g, 16.0 mmol) in 20 mL of degassed methanol. To this solution is added rhodium (R,R) DiPAMP (20 mg, 0.026 mmol). The solution is then flushed with nitrogen five times and then with hydrogen five times and hydrogenated t 40 psig for 4 h. The bottle is opened and the solution concentrated in vacuo to give an oil, 5.03 g, 100% of product that is purified by flash chromatography over silica gel to give 4.89 g, 97% of N-Cbz-L-phosphonoalanine as an oil. Evaluation of the optical purity of this product by chiral vapor phase chromatography on a Chirasil Val III 25 meter column revealed that 95% of the material was (R) and 5% was (S), for an enantiomeric excess of 90%.
Using analogous method with appropriate corresponding starting materials the following compounds are prepared using the processes of the present invention.
TABLE 1______________________________________R.sub.1 R.sub.3 % Yield % ee______________________________________H C.sub.6 H.sub.5 CH.sub.2 OCO 95 90C.sub.6 H.sub.5 -- HCO 86 100C.sub.6 H.sub.5 C.sub.6 H.sub.5 CH.sub.2 OCO 93 98p-C.sub.6 H.sub.5 CH.sub.2 OC.sub.6 H.sub.4 -- C.sub.6 H.sub.5 CH.sub.2 OCO 93 98(CH.sub.3).sub.2 CH C.sub.6 H.sub.5 CH.sub.2 OCO 97 881-naphthyl C.sub.6 H.sub.5 CH.sub.2 OCO 97 98cyclohexyl C.sub.6 H.sub.5 CH.sub.2 OCO 95 91______________________________________ | This invention is selected novel chiral (essentially pure) alpha-amino phosphonates, process for the preparation which is a catalytic asymmetric hydrogenation of olefins and novel intermediates therefor. The alpha-amino phosphonates are useful as antibiotics and/or as intermediates in the preparation of phosphorus-containing analogs of peptides, i.e., phosphonopeptides or pseudopeptides having known uses, such as in antibiotics, antibiotic enhancers, or enzyme inhibitors. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a process for producing false-twist textured yarn, and is more particularly concerned with applying false-twist to yarn with hollow friction tubes.
False-twist texturing processes have used a variety of devices for applying false twist. The hollow friction tube, fitted with a toroidal bushing of high friction material on each end, is a particularly preferred type of false twister. One advantage of such a twister is its high rate of twist generation, due primarily to the fact that many turns of twist are inserted into the traveling yarn for each rotation of the tube. Such tubes are, moreover, relatively easily and inexpensively fabricated. Stringup of yarn through their relatively large axial openings is simple, and they are small enough to be readily positioned on existing yarnhandling equipment such as uptwisters, downtwisters, draw twisters, and the like. When increased torque is desired for obtaining a given degree of twisting, two (or more) hollow friction tubes may be used in series, as is known.
Hollow friction-twist tubes have been fitted at each end with identical toroidal bushings of deformable elastomeric material with high yarn-to-bushing friction and good resistance to wear. Generally the materials used for bushings comprise either hard rubber or synthetic elastomers (e.g., polyurethanes).
As higher and higher processing speeds are attempted, eventually a point is reached at which yarn instability occurs with the result that twist insertion becomes erratic and spaced twisted sections of yarn slip through the friction tube. The onset of instability can be moved to a greater yarn speed by increasing the yarn tension so as to keep the yarn more firmly in contact with the friction surfaces. This approach, however, quickly leads to tensile failure of the yarn being processed. Moreover, increase of yarn tension during false twisting undesirably increases the amount of shrinkage of the packaged yarn.
Chimura et al. disclose in German Patent No. 2,245,468, dated Apr. 5, 1973, that it is possible to produce a uniform and strong crimp even at a yarn running velocity of above 300 meters per minute, and to produce thereby a uniform crimped and bulked yarn, when the value of 1000 V/S is between 300-D and 500-D, and the ratio of T 2 /T 1 is below 2, where:
V is the yarn running velocity in m/min. on the frictional surface producing the twist,
S is the peripheral velocity in m/min. in the middle of the frictional surface part cooperating with the yarn,
D is the denier count of the yarn to be crimped,
T 1 is the yarn tension in grams at the inlet side of the twist producing tube, and
T 2 is the yarn tension in grams at the exit side of the twist producing tube.
The patent teaches that the process can be used with all thermoplastic synthetic yarns for which false twisting is possible. The process is illustrated with conventional polyester an polyamide feed yarns; the illustrations include ones where the operations of drawing and false-twist texturing are combined. The false-twist texturing equipment disclosed appears to be conventional except for the use of a cooling roll between the heater and the false-twist tube. Most of the illustrations use a tube fitted at each end with a toroidal bushing of a wear and tear resistant material with a high frictional value, polyurethane being the only material mentioned, and having an inner diameter of 35 mm. at the middle part of the surface cooperating with the yarn.
The present invention is an improvement over processes such as that of the above patent.
SUMMARY OF THE INVENTION
The invention provides a more favorable distribution of yarn tensions between the inlet and outlet bushings with a higher level of applied torque, resulting in more crimp or bulk in the false-twist textured product. The invention also provides a higher tension level upstream of the twister for any given tension level downstream from the twister. A higher level of torque application can be used without encountering twist slippage past the twister. The invention also provides for generally lower tensions downstream of the twister to reduce yarn shrinkage in the product without loss of bulk.
The improvements in the false-twist texturing process comprise feeding the yarn under a tension T 1 from the heater over a high friction toroidal surface located at an end of a friction-twist tube at an angle α of at least 85° to the yarn path, then passing the yarn over a low friction toroidal surface located at an end of a friction-twist tube at an angle β of less than 80° to the yarn path and having a surface velocity no greater than that of the high friction surface, and withdrawing the yarn from the friction-twist tube under a tension T 2 where T.sub. 2 /T 1 , has a value of 1 to 2.
The angles α and β are angles between the axis of revolution of the toroidal surfaces and the yarn path to or away from the surface, as measured around the outside of the toroidal surface. The angle α is preferably from 90° to 110° , and the angle β is preferably from 50° to 80°. The toroidal surfaces are usually formed by gaskets inserted in opposite ends of a hollow friction-twist tube, but can be positioned in different tubes of a twisting device.
The second toroidal surface must provide a lower yarn-on-surface friction than the first surface. This can be accomplished by using gaskets of different materials which differ in surface friction, e.g., polyurethane and apiprene, of polyurethanes of different hardness. Preferably, a synthetic elastomer is used for the high friction surface and an extremely hard material, such as nickel-boron, is used for the low friction surface. Gaskets of the same shape and dimensions can be used. Preferably, the low friction surface has a lower surface velocity than the high friction surface, which further decreases the effective friction of the yarn. This can be accomplished by using toroidal surfaces which have different inner diameters, or by mounting the low friction gasket on a separate twisting tube which is rotated at a lower speed than the twister tube having the high friction surface.
It is quite surprising to find that decreasing the friction of the second surface, while keeping constant conditions at the high friction surface, increases the applied turns per inch of yarn twist and results in higher yarn crimp and bulk in the final product.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of one embodiment of the process and suitable apparatus for use in the process.
FIG. 2 is an enlarged cross-sectional view on a plane passing through the axis of the false twist rotor to show the configuration of the yarn-engaging bushing.
FIG. 3 is a schematic representation of another embodiment of the process and suitable apparatus for use in the process.
DETAILED DESCRIPTION
As shown in FIG. 1, undrawn yarn 10, from a suitable source, passes through guide 12 to cot roll 14, passes part way round the cot roll and then through the nip between the cot roll and driven feed roll 16. From the feed roll, the yarn passes around unheated draw pin 18 and takes several turns about draw roll 20 and its associated separator roll 22. The relative speeds of the feed roll and the draw roll are adjusted to provide the required draw ratio. Drawn yarn 24 departs from the draw roll tangentially through the nip with a spring-loaded nip roll (not shown) which prevents back-up of false twist around draw roll 20. Drawn yarn 24 then passes axially through the central opening of heater 26, which is a double helix of electrical resistance wire as described in Example I of U.S. Pat. No. 3,732,395. Yarn temperature at exit from heater 26 is about 185°C. The yarn heater utilized to provide the desired yarn temperature at this point may be of any type customarily employed for heat setting during false twisting. Yarn 24 is then twisted and untwisted in a false twist step, as is fully understood.
The false twist device employed is an electric motor 28 having a hollow rotor (not shown) to which is attached, at each of its 2 ends, a polyurethane bushing. FIG. 2 shows the cross-section of each bushing as obtained in a plane passing through the axis of rotation 34 of the rotor of motor 28. In FIG. 2, yarn progresses along directions 53 for an inlet bushing (reversed for outlet bushings) in contact with surface 50 of the bushing 51. Bushing 51 fits into the end of the hollow rotor 52 of the electric motor. As shown in FIG. 2, the inside of the hollow rotor is vertically above bushing 51 and extends to the left.
All the bushings used in the examples have identical sizes and shapes. They fit into the end of a hollow rotor having a 0.783 inch inside diameter to leave an opening through the torus-shaped bushing which is 0.625 inch in diameter. Overall length of each bushing (left to right in FIG. 2) is 0.58 inch, and outside maximum bushing diameter is 1.27 inches.
Referring again to FIG. 1, yarn 24 enters the twister around the lip of inlet bushing 30 and leaves around the lip of outlet bushing 32. The yarn path is characterized by inlet angle α and outlet angle β with respect to the axis 34 of rotation of the bushings. Inlet angle α is preferably established solely by angular orientation or motor 28. Outlet angle β may require the use of an additional yarn guide near bushing 32. From bushing 32, textured yarn 24 takes several wraps around draw roll 20 and separator roll 22 before passing via guide 36 to customary ring-and-traveler windup on pirn 38.
As shown in FIG. 3, undrawn yarn 60 from a suitable source is forwarded by passage through the nip between driven feed roll 64 and associated cot roll 62. Proceeding via guides 65, yarn 60 runs against hot plate 66 up to and through the hollow rotor (not shown) of electric motor 68. Inlet 70 and outlet 72 bushings of polyurethane are fastened to the ends of the hollow rotor. Yarn 60 contacts only the exposed surfaces of bushings 70 and 72 in passing through the rotor. Because the bushings rotate at high speed about axis 74, their frictional contact with running yarn 60 imparts a high level of false twist, as is well understood. Bushings 70 and 72 are geometrically identical to those discussed above. The twisted and untwisted yarn then passes to draw roll 76 and makes several turns around draw roll 76 and associated separator roll 78. The ratio of the peripheral velocity of draw roll 76 to that of feed roll 64 is the draw ratio, the actual drawing of the yarn occuring during the initial stage of heating on hotplate 66. Drawn and textured yarn 80 proceeds to windup as indicated in FIG. 1.
In the examples which follow, the following definitions and test methods apply.
Denier. This is the weight in grams of 9000 meters of yarn which is extended to remove the applied crimp. The weight of a much shorter length is actually measured and then converted to denier.
Crimp Index (CI) and Crimp Shrinkage (CS). A 750 denier skein of yarn is prepared by winding the requisite number of turns onto a reel to yield a skein which is about 55 cm. long when suspended freely with a weight attached at its bottom. The denier of the collapsed skein is, of course, twice that of the wound skein, i.e., 1500 denier. Initially at 500 gm. weight is suspended from the skein and, after 1 minute, its length L 1 is measured and recorded. The 500 gm. weight is then replaced with a 1.8 gm. weight, the skein is exposed to 100°C. steam at atmospheric pressure for 1 minute, it is dried in air for 10 minutes, and then its crimped length L 2 is measured and recorded. Finally, the 500 gm. weight is again attached and, after 1 minute, extended length L 3 is measured and recorded. ##EQU1## Turns per inch (TPI). This is a measure of the twist actually inserted by the hollow friction-twist tube. While the yarn is being processed, a sampling device very similar to a mousetrap is used to snatch a sample from the twist region immediately adjacent to the inlet bushing of the twister. The turns in a known length of the snatched sample are directly counted, the count being converted to turns per twisted inch.
Crimps per inch-restrained (CPIR). A length of textured yarn is removed from its package and taped to a black felt board without permitting any twist to occur. Two filaments are carefully separated out from the yarn so as to be parallel with about 0.75 inch separation. One pair of adjacent ends is fastened to a piece of adhesive tape cut to provide 7 mg./denier tension (weight in mg. is 14 times the denier per filament). The other pair of adjacent ends is also fastened to a piece of adhesive tape by which the assembly is suspended. Saturated steam is played onto the assembly for 1 minute and then the parallel filaments are taped to a glass microscope slide while still suspended in air. After the ends are cut off, a half inch length of one filament is projected optically onto a projection screen from which the number of crimps developed is counted. This count, multiplied by 2, is CPIR.
EXAMPLE I
This example uses process and apparatus embodiments disclosed in FIG. 1, and described previously, to treat undrawn, three-filament, polyhexamethylene adipamide yarn. After drawing the yarn is 18 denier.
Several yarns are produced, using the process conditions shown in Tables I and II. Inlet bushings G are always identical, having a high yarn-to-bushing friction. Outlet bushings A are of lower yarn-on-bushing friction than the inlet bushings, and outlet bushings G, which are identical to the inlet bushings, are used in comparison tests. Varying outlet angles (β) are also employed. The peripheral speed of the draw roll is 700 yards per minute to provide a draw ratio of 4.100 (ratio of drawn to undrawn length) in each test.
As an indication of relative yarn-on-bushihing friction levels for the "G" and "A" bushings, tension measurements are made on yarns being processed as shown in FIG. 1 and described above except that two hollow-rotor electric motors are used. The first motor has only an exit bushing about which the yarn changes direction by 80° while in contact. The second motor has only an inlet bushing about which the yarn makes a further change in direction of 50° while in contact. A distance of 3 inches separates the two bushings. Both electric motors rotate at 16,200 rpm. Tension (T 1 ) on the yarn just prior to contacting the bushing of the first motor and tension (T 2 ) on the yarn just after contacting the bushing of the second motor are measured. When both bushings are G bushings, T 1 = 4.0 gm., T 2 = 23.5 gm., and T 2 /T 1 = 5.88. When both bushings are A bushings, T 1 = 6.5 gm., T 2 = 22 gm., and T 2 /T 1 = 3.38. While the precise equation for computing friction coefficient from this arrangement of parts is not known, it is well known that friction coefficient (f) is approximately proportional to the logarithm of T 2 /T 1 . Thus, ##EQU2## clearly showing a significantly lower friction coefficient for the A bushings.
Table I present the process variations used for the tests. Table II presents the twist and tension results obtained.
TABLE I______________________________________PROCESS VARIATIONSBushing Motor Speed Angles (degrees)Test In Out RPM α β______________________________________1A G G 20,000 85 501B G A 20,000 85 501C G A 20,000 85 851D G A 24,000 85 501E G A 24,000 85 501F G A 24,000 85 801G G G 24,000 85 80______________________________________
table ii______________________________________twist and tension results tension (gm.) Outlet/InletTest TPI In Out Tension Ratio______________________________________1A 131 7 17.2 2.461B 148 9 16 1.781C 162 81/2 181/2 2.181D 158 8 16 2.001E 167 10 17 1.701F 171 10 141/2 1.451G 171 7 181/2 2.64______________________________________
Test 1A is a comparison test using identical inlet and outlet bushings. Test 1B is like Test 1A in every respect except that the lower friction A bushing is used at the outlet. Higher applied twist (TPI) and lower tension ratio result. Test 1C duplicates Test 1B except that outlet angle β is increased from 50° to 85°. Applied twist increases further, but at an increased tension ratio. Tests 1D through 1G generally repeat tests 1A to 1C, but at a higher twist-motor speed. Comparing 1D with 1B, more twist is inserted at about the same tension ratio. Test 1F repeats Test 1D except for increasing outlet angle β. Slightly increased twist results, but the tension ratio is surprisingly reduced. Test 1G is like Test 1F except for use of identical inlet and outlet bushings, which is seen to dramatically increase the tension ratio.
The above data demonstrate that the use of lower-friction outlet bushings results in the insertion of more twist and a reduction of the ratio of outlet to inlet yarn tensions. Proper selection of outlet angle β is also important, but does not change the above conclusions.
EXAMPLE II
This example uses process and apparatus embodiments disclosed in FIG. 3, and described previously, to treat undrawn feed yarn.
Spun polyhexamethylene adipamide yarn with seven filaments and a total denier of 53 is drawn and false twisted as described. Yarn speed on draw roll 76 is 850 yd./min. to provide a draw ratio of 2.619. Hot plate 66 is 20 inches long and heated to 230°C. surface temperature. Yarn 60 contacts hot plate 66 only along 10 inches of its length. Inlet yarn angle α is 90°, and outlet angle β is 69°. Rotational velocity of bushings 70 and 72 is 30,000 rpm. Windup of drawn and textured yarn 80 is at a yarn speed 5.3% less than the draw-roll velocity. Bushing friction is indirectly measured in terms of hardness in degrees of International Rubber Hardness using a Shore Type A Durometer (ASTM Test No. D1415-56T). The harder the bushing, the lower is the yarn-to-bushing friction.
In test 2A, the inlet bushing has a Shore A hardness of 80° and the outlet bushing a Shore A hardness of 97°. In comparison test 2B, both bushings have a Shore A hardness of 80°. Yarn tension T 1 immediately prior to reaching bushing 70 and yarn tension T 2 immediately after leaving bushing 72 are measured (Any customary yarn tensiometer suffices. A Rothschild electronic tensiometer is employed). Critical processing parameters are given in Table III, and yarn properties obtained are shown in Table IV. It is seen that use of a lower friction outlet bushing (Test 2A), as compared to use of identical inlet and outlet bushings (Test 2B) results in lower crimp shrinkage (CS), increased stretch (CI), lower T 2 /T 1 ratio, and a higher level of input tension T 1 .
EXAMPLE III
This example duplicates Example II in all respects except for increasing inlet angle α to 100°. Test 3A uses bushings identical to those of Test 2A; and Test 3B is a comparison test using bushings identical to those of Test 2B. As in Example II, critical process and product properties are shown in Tables III and IV. Again it is seen that the use of lower friction outlet bushings provides lower crimp shrinkage (CS), increased stretch (CI), lower T 2 /T 1 ratio, and a higher level of input tension T 1 . It is seen further that use of an inlet angle α exceeding 90° results in still further improvements of the same kind.
EXAMPLE IV
Example III is repeated identically in every respect except for reducing outlet angle β from 69° to 62°. Comparison of Test 4B with comparison Test 4A confirms the previous improvements resulting when the outlet bushing is of lower friction than the inlet bushing. Comparison of Test 4A with Test 3A, or Test 4B with Test 3B, shows that reduction of outlet angle β affects results very little. There is, however, a slight desirable shift of outlet tension T 2 to the inlet side (T 1 ). Crimp shrinkage (CS), on the other hand, is significantly increased.
EXAMPLE V
The process as shown in FIG. 3 and generally as described in Example II is employed to produce four-filament false-twist textured yarns of polyhexamethylene adipamide. The undrawn feed yarn is one designed to provide a nominal total denier of 18 when drawn. The draw ratio employed is 3.878 at a draw roll peripheral speed of 870 yd./min. The yarn contacts the full 20-inch length of the hot plate, which has a surface temperature of 189°C. The twister bushings rotate at 33,000 rpm. Inlet angle α is 90°, and outlet angle β is 69°. In Test 5A, the inlet bushing is of polyurethane having a Shore A hardness of 80°. The outlet bushing, however, is a geometrically identical bushing of acrylonitrile-butadiene-styrene) (ABS) polymer coated with a smooth uniform layer of nickel-boron to a thickness of about 0.001 inch. This coating is applied by tumbling the preformed ABS bushing in an electroless plating bath at a pH of about 6.4 and a temperature of 55°C. The electroless plating bath is composed of: 50 gm./l. of nickel acetate, 25 gm./l. of dihydrated sodium citrate, 25 gm./l. of lactic acid, 2.5 gm./l. of dimethylamine borane, 0.1 gm./l. of thiodiglycolic acid, and 0.1 gm./l. of a commercial wetting agent. The smooth coated bushing is too hard to obtain a meaningful reading using the Shore Type A Durometer (i.e., it reads 100°). In comparison Test 5B, both bushings are identical polyurethane bushings having a Shore A hardness of 80°. Again it is shown that a lower friction outlet bushing decreases crimp shrinkage (CS), increases stretch obtained (CI), and very favorably decreases the outlet-to-inlet tension ratio while simultaneously increasing the level of inlet tension.
TABLE III______________________________________PROCESS VARIATIONSBushing HardnessShore A Angles Tension Outlet/Inlet(degrees) (degrees) (gm.) TensionTest In Out α β In Out Ratio______________________________________2A 80 97 90 69 11.8 16.0 1.362B 80 80 90 69 8.0 17.8 2.223A 80 97 100 69 11.5 15.4 1.343B 80 80 100 69 8.5 18.0 2.124A 80 97 100 62 11.8 15.3 1.304B 80 80 100 62 9.5 16.8 1.775A 80 >100 90 69 10.7 10.8 1.015B 80 80 90 69 8.6 13.6 1.58______________________________________
TABLE IV______________________________________YARN PROPERTIESTest Denier Elongation (%) CI (%) CS (%)______________________________________2A 21.3 32 54.1 6.32B 21.4 36 49.5 7.13A 21.4 36 56.7 6.03B 21.3 38 54.9 6.74A 21.5 38 55.7 6.94B 21.6 37 55.3 7.55A 17.8 22 67.1 3.15B 17.7 22 66.6 3.6______________________________________
EXAMPLE VI
This example shows the effect of operating the inlet and outlet bushings at different peripheral twisting velocities. Processing is as described in Example I, but using two hollow-rotor motors each with one bushing as described for determination of relative friction coefficients of the two types of bushings. In this example, both bushings are of the G variety. Inlet angle α is 85° and outlet angle β is 50°. Peripheral velocity of the draw roll is 700 yd./min. Results are:
Motor Speed Tension(RPM/1000) Tension (gm.) RatioTest In Out In Out (T.sub.2 /T.sub.1) TPI CPIR______________________________________6A 20 20 6 17 2.8 154 186B 22 20 7 20 2.8 158 216C 24 20 8 18 2.2 167 22______________________________________
It is apparent that, as the peripheral velocity of the outlet bushing becomes progressively less than that of the inlet bushing, more tension is transferred to the inlet bushing. Both applied twist (TPI) and crimp level developed (CPIR) increase correspondingly.
In a comparable process utilizing a single twist tube with a bushing on each end, the same results are obtained if the outlet bushing has a smaller effective diameter for its yarn-contact surfaces. | False-twist texturing processes which apply twist with hollow friction tubes, fitted at each end with a toroidal bushing, are improved by using a high friction bushing at the yarn inlet and a lower friction bushing at the yarn outlet. Further improvements are provided by adjustments in the yarn inlet and outlet angles, and the speeds of the bushing surfaces. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a portable, foldable beach screen which provides privacy and protection from wind and blowing sand for a reclining individual. More specifically, the invention relates to such an apparatus which is constructed from a single panel and is foldable into a compact and easily carried configuration. The screen may include a reflective material on one or both major surfaces and can carry advertising messages or other printing.
2. Background Art
Beachgoers are well aware that even a slight breeze blowing across the sand can be an annoyance for the reclining sunbather. Blowing sand deposited on the individual detracts from the otherwise pleasurable environment, yet is difficult to avoid. The chilling effect of a cool breeze, even absent blowing sand, can be undesirable and uncomfortable as well. Thus, one of the needs in the art is a portable beach screen which functions as a barrier to wind and sand for the reclining sunbather or beachgoer by means of a beach screen which will remain upright in even a substantial breeze.
Beachgoers may also desire a degree of privacy while sunbathing or otherwise reclining and this, too, may be difficult to obtain. Others in the immediate vicinity of the individual may annoy by kicking sand, and a physical barrier between the individual and her annoying neighbors can provide a degree of comfort. There is a need in the art to provide a portable beach screen which functions as a privacy screen for the beachgoer.
Other needs are a beach screen which provides a full body tanning device as well as a vehicle for advertising or other printed messages. These needs are fulfilled by a beach screen which can be manufactured quite inexpensively and thus is highly appropriate as a `give away` item for businesses located on or near the beach. Advertising slogans or other messages imprinted upon the screen will be highly visible to the beachgoing population. When one or both surfaces of the present beach screen are covered with a highly reflective material, the screen can be employed to reflect the sun's rays upon the sunbather.
A variety of devices intended to protect the beachgoer, and/or to provide a highly reflective surface for suntanning, are found in the prior art. None provide the simple and inexpensive construction and high versatility provided by the present beach screen, however.
U.S. Pat. No. 2,981,256 (Besnah; Apr. 25, 1961) discloses a protective and reflective device for use on the beach. The device is constructed from a plurality of individual panels interconnected by hinges. Thus, the cost to manufacture this device would be substantial.
U.S. Pat. No. 3,463,577 (Friedberg; Aug. 26, 1969) relates to a sun reflecting board adapted to be placed over the head of a sunbather. Although the patent illustrates that the board can be stood up on the sand, the board includes no provision to prevent it from falling over in a breeze. This device does not seem well suited as a screen for blocking wind and blowing sand.
U.S. Pat. No. 1,930,404 (Wagner; Oct. 10, 1933) discloses a privacy screen for beachgoers. Fabric panels are suspended from stakes driven into the sand. This device is not foldable and highly portable.
SUMMARY OF THE INVENTION
The present invention provides a portable and foldable beach screen apparatus comprising a single unitary panel means constructed of a material which is impervious to air flow, the panel means comprising a plurality of panel members foldable about one another from a first, fully folded configuration wherein each of the panel members are juxtaposed over one another to a second, fully deployed position wherein the panel means is of substantially planar configuration, each of said panel members comprising a slot means for engaging a support stake means, and support stake means for supporting the apparatus in the ground, the support stake means passing through said slot means and into the ground.
The inventive beach screen fulfills each of the needs discussed above by providing a lightweight yet sturdy screen which is quite inexpensive to manufacture. One or both major surfaces may be covered with a highly reflective material and may be imprinted with an advertising or other message. The screen can be erected into a variety of configurations and is staked into the ground or sand for security against blowing over. The screen is readily folded into a compact and easy to carry configuration. In this folded configuration the stakes are held within a special tab in one of the panels so that they do not become separated from the screen and lost.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view of the interior side of the present beach screen.
FIG. 2 is a view of the exterior side of the present beach screen.
FIG. 3 is a view of the present beach screen in an erected configuration.
FIG. 4 is a view of the present beach screen in a folded configuration.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the present portable and foldable beach screen is seen to be comprised of a single, unitary panel 10. Panel 10 can be constructed of any air (and preferably light) impervious lightweight material, so long as the material lends itself to being repeatedly folded and unfolded along fold lines 20. Fold lines 20 are established within the panel 10 during the manufacture of the screen. For example, in my preferred embodiment panel 10 is constructed of two hundred pound test corrugated cardboard. Fold lines 20 are calendared into the panel during the cutting of the same.
As seen in FIG. 1, fold lines 20 serve to subdivide panel 10 into a number of individual panel members 30. These panel members can be angled with respect to one another so that the screen can be erected in a variety of configurations. One such configuration is seen in FIG. 3, and it will be appreciated that many other configurations are possible.
The preferred embodiment which is illustrated in FIG. 1 includes a panel 10 constructed of a unitary piece of corrugated cardboard measuring sixty inches (cm.) long by eighteen inches (46 cm.) high. The panel 10 is subdivided by three fold lines 20 into four panel members 30 of equal size measuring fifteen by eighteen inches (by 12 cm.). It will be apparent that the number and size of the individual panel members can be varied as desired.
The preferred embodiment includes a highly reflective surface material (designated by reference numeral 40 in the Figures) on the inside-facing major surface of panel 10. A thin layer of silver-colored metallic foil is preferred as it provides a high degree of reflectance, and corrugated cardboard coated with such a material is commercially available.
It is also seen in FIG. 1 that each of the individual panel members 30 has a handle opening 50 centered along its upper edge. The handle openings are identically placed within each panel member so that they align when the beach screen is folded for carrying. This is best seen in FIG. 4.
FIG. 2 illustrates the outer-facing surface 60 of the present beach screen. In the preferred embodiment this surface does not include the highly reflective coating, as reflections from this outer surface could prove distracting and/or annoying to others on the beach. Surface 60 is well suited to carry advertising slogans or messages, and these are most effective when confined to an individual panel member 30 so as not to be rendered unreadable by certain configurations of the beach screen.
The stakes 70 used to secure the screen in the sand or ground are seen in their stored position in FIG. 2. Three stakes are included with the four panel preferred embodiment, and these are stored for carrying by securing them under tab 80 in the end panel. Stakes constructed of either lightweight wood, such as pine, or of plastic, are preferred due to their sturdiness and low cost. The stakes should be somewhat longer than the height of the beach screen so that the lower three to six inches can be driven into the sand or ground, while an upper portion of similar length projects beyond the upper surface of the panel members. As seen in FIG. 4, however, the stakes should be slightly shorter than the diagonal dimension of the panel members so that the stakes do not project beyond the edges of the panel when the screen is in its fully folded configuration. The stakes are tapered at their lower ends in order to facilitate their entry into the ground, but are not so sharp as to present a danger to the consumer.
FIG. 3 shows one of the many ways in which the present beach screen can be erected and secured. As seen in this Figure, stakes 70 are passed through pairs of tabs 90 and then into the sand or ground. Again, it will be appreciated that many other configurations are possible. Also, two or more beach screens can be combined to erect longer or larger barriers or privacy screens.
The ability to fold the screen into a compact, easily handled configuration is a key feature of the present invention. FIG. 4 illustrates this configuration; the folded unit has the dimensions of one of the individual panel members, and the stakes are secured within their tab in the end panel member to prevent their loss.
Although the present portable and foldable beach screen has been described and illustrated in connection with certain preferred features and embodiments, it is not limited thereto. Numerous modifications within the scope of the following claims will be apparent. | A portable, foldable beach screen provides privacy and protection from wind and blowing sand for a reclining individual. The screen is constructed from a single panel and is foldable into a compact and easily carried configuration. The screen may include a reflective material on one or both major surfaces and can carry advertising messages or other printing. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to lounge chairs for children and more particularly to a combination lounge and rocking chair.
2. Description of the Prior Art
In todays society most parents go to considerable means to provide their children with comfortable toys and play devices to keep them quiet and entertained. However, when the child is large enough to sit up on a conventional chair problems develop rapidly in that he seldom rests there quietly for any length of time. After a while he starts to squirm around and may eventually slide off the chair to respond to his need to move about and be active. Attracted by the motion of the family rocking chair the child is usually quite content to sit in it and rock back and forth. Primarily for this reason small size rocking chairs have been produced for the entertainment of small children essentially constructed of a chair mounted on arcuate rails or rockers. Such a rocking chair tends to satisfy the child's need to release body energy but likewise may cause some damage to the child as well as to other objects of furniture in the room. Frequently, a child will rock so violently it causes the chair to tip over and throw him forwardly or backwardly. Should a coffee table or another article or piece of furniture be in the way he may well injure his head, break an arm or leg. In the event he does not get hurt there is always the possibility that the rocking chair will strike and scar a piece of furniture.
As far as applicant knows neither rocking chairs for children or adults are manufactured with built-in means, such as a bumper guard, to limit the angle of tilt in any position or direction. This applies equally as well to conventional rocking chairs and to other forms of rocking devices.
In regard to the latter, multipurpose rocking, reclining and lounging chairs have been proposed that will safely permit an occupant to rock thereon without turning over. A chair of this type is shown in U.S. Pat. No. 3,526,429 issued to H. M. Metzgar. The Metzgar chair consists of a pair of spaced side panels with lower generally arcuate edges in rocking contact with a floor. Each side panel edge has a straight forward portion, a complemental straight rearward position at right angles to the forward portion and an intervening portion which is curvilineal and of a predetermined arc. Several angularly related pallet-like panels are fixedly suspended in the space between the side panels. The alleged self-balancing position of the cradle-like chair provides the occupant a reclining rocker which, in the forward upright position, is a stationary seat and in the rearward position he is reclining with his back parallel to the floor and legs extending upwardly. While it appears that the Metzgar chair will not tip completely over in the fore and aft movement it obviously will not rock in any other direction and therefore is largely limited to a stationary position on the floor. Furthermore, this chair could throw a child out when rocked sufficiently hard backwardly and possibly cause an injury.
A somewhat similarly constructed rocking chair is shown in U.S. Pat. No. 2,482,306 issued to J. J. Waldheim. The Waldheim tilting chair has two spaced side supporting members formed generally into an L-shaped loop of metal tubing. The structure could also be of solid plywood panels essentially of the same design shown in the Metzgar drawing. The two side supporting members are connected by several cross-members to hold them in fixed rocker position. Spaced between the side members is a canvas cover forming the back, seat and leg rest. The Waldheim chair apparently operates in the same manner described by Metzgar and has the same disadvantages for a child's use. It also lacks side supporting structure to prevent a child from tumbling sideways off of the chair.
Therefore, it is the object of the present invention to provide an ellipsoidal-shaped rocking lounge chair in which a child can recline and rock safely as actively as he wishes. Another object is to provide a chair with a bumper guard which will prevent it from turning completely over. Yet another object is to provide a seating or reclining arrangement which will allow the child to rock or rock and rotate the rocking lounge chair in such a manner as to make it travel about on a ground surface in a straight or spiral path without falling out of the chair.
SUMMARY OF THE INVENTION
In carrying out the principles of the present invention in accordance with a preferred embodiment thereof, a generally ellipsoidal-shaped body has a top surface. In the top surface a forwardly extending rectangular opening has an upper short side and a pair of spaced apart downwardly sloping long sides including a lower short side at the front end of the body. The lower surface is adapted for rocking on a ground surface. A body rest depending downwardly in the opening has a pair of spaced apart sidewalls connected at their upper edges to the long sides of the opening and the lower edges to an L-shaped bottom wall. The bottom wall has a downwardly and forwardly extending back portion connected with the upper short side of the opening, a horizontally extending seat portion and a downwardly and forwardly sloping leg portion connected to the short side at the lower end of the opening. There are bumper means extending around the body spaced from the ground surface for rocking contact with the ground surface when rocked by a child reclining in the body so as to prevent the body from tilting beyond a safe angle from the verticle. The bumper means is adapted to exert a reactive force and urge the body towards an upright position.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side elevational view taken partly in section through a device representing the present invention,
FIG. 2 is a top plan view of FIG. 1 taken along line 2--2,
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 1 showing the seat portion of the body rest,
FIG. 4 is a modified form of FIG. 1 taken partly in section,
FIG. 5 is a top plan view of FIG. 4 taken along line 5--5,
FIG. 6 is a cross-sectional view taken along line 6--6 of FIG. 5 showing the pair of handholds and channels in the leg rest portion of the body, and
FIG. 7 is an isolated fragmented view of one of the incremental sides and handholds at the juncture of the first section and the second section of the rectangular opening.
DETAILED DESCRIPTION
Referring to FIGS. 1 and 2 it can be seen that the present invention consists of a generally ellipsoidal-shaped body 10 which has a top surface 11 and a lower surface 12 suitably formed for rocking on a ground surface 13. In the top 11 a rectangular opening 14 extends from in rear of and adjacent to the central verticle axis of body 10 forwardly to the front end 15 of body 10. Opening 14 has an upper short side 16 including a pair of spaced apart long sides 17 sloping downwardly to a lower short side 18. Suspended downwardly in opening 14 is an angularly related body rest 19 comprising a pair of spaced apart side walls 20 which have their upper edges 21 connected to long sides 17 of opening 14 and lower edges 22 connected to an L-shaped bottom wall 23 arranged to conform to the posterior of a reclining child. Bottom wall 23 is formed into a downwardly and forwardly extending back portion 24 from a connection with upper short side 16 of opening 14 including a horizontally extending seat portion 25 and further a downwardly and forwardly sloping leg portion 26 connected to short side 18 at the lower end of the opening. Around the lower surface 12 of body 10 is a bumper guard 27 spaced from ground surface 13 so as to limit the rocking movement of body 10 in any direction to a safe angle of tilt of approximately 25° from the verticle. It is to be understood that by varying the ratio of the major diameter to the minor diameter of body 10 and the height of the position of bumper guard from the ground other safe angles of tilt can be achieved. However, a preferable ratio of minor diameter to major diameter is 1 to 1.7 and the height from the center line of the bumper guard 27 to ground surface 13 is approximately one-third of the distance from the major axis to said ground surface for a safe angle of tilt of approximately 25° from the verticle. Therefore, when bumper guard is rocked in contact with ground surface 13 the reactive force of impact acts on body 10 to urge it upwardly towards an upright position.
A modified form of the present invention is shown in FIGS. 4, 5 and 6. Referring to FIG. 5, it is seen that the somewhat irregular rectangular opening consists of a first section 28 and a second section 29. The first section 28 has an upper short side 30 and a pair of spaced long sides 31 sloping downwardly to an open end juncture with left and right incremental sides 32 of the wider second section 29. Second section 29 has a pair of spaced short sides 33 sloping downwardly from the incremental sides 32 to a lower connection to a long side 34 at the front end 15 of body 10. Suspended downwardly within the first and second sections is a body rest 35 comprising a pair of spaced side walls 36 connected at their upper edges 37 to long sides 31 of the first section 28, then to incremental sides 32 and the downwardly sloping short sides 33 of second section 29. At the juncture of the first and second sections side walls 36 are formed at right angles and parallel to left and right hand incremental sides 32 and than again at right angles and parallel to downwardly sloping sides 33 of second section 29. The lower edges 38 of side walls 36 are further connected to an L-shaped bottom wall 39 adapted to support the posterior parts of a reclining child. Connected also to upper short side 30 of first section 28, bottom wall 39 is formed downwardly and forwardly into back portion 40, horizontally extending seat portion 41 and downwardly and forwardly sloping leg portion 42 to a connection with long side 34 at the lower end of second section 29. To provide a child with the means for mounting or rising from body rest 35 as well as a hand gripping member on which to hang when rocking body 10 handholds 43 are formed at the juncture of the first and second sections. Handholds 43 are essentially formed into semi-cylindrical rolls projecting laterally from the upper edge connection of side walls 36 to the left and right hand incremental sides 32. An illustration of handhold 43 is shown in FIG. 7. To further provide comfortable means for reclining on bottom wall 39 a slight convex bulge 44 is formed in back portion 40 to support the child's lower back region, a shallow basin 45 formed in seat portion 41 to support his buttocks and a pair of spaced channels formed in leg portion 42 to support his legs.
In operating the present invention a child simply lowers himself onto the bottom wall 39 and grasping handholds 43 prepares to activate body 10 into rocking motion. If he sits up straight in the seat portion 41 or leans back against back portion 40 without moving about or shifting his weight suddenly the relatively broad curvature lower surface 12 resting on ground surface 13 will hold body 10 in a reasonably stable upright position. When the child wishes to activate the body into rocking motion he can grasp handholds 43 and throw his weight in the direction he wishes the body to rock. The directional change in the child's weight will impart momentum to the body and cause it to tilt forward, backward or sideways until bumper guard 27 strikes ground surface 13. When the bumper guard contacts the ground movement of the body tending to tip over is halted and if the impact is hard enough a reactive force is imparted on the body uring it towards an upright position. The upward momentum together with the child's weight shifting momentum causes the body to swing past the verticle position and start downward again in the opposite direction until the bumper strikes the ground on the other side of the body. The rocking movement will continue as long as the child chooses to keep the body in motion and he can manipulate the movement so as to rock at any angle in a circle of 360°. By causing the body to change direction in the process of rocking back and forth he can make it wobble around a circular path or travel on the floor from wall to wall. This is accomplished by making the bumper strike the ground on one side of the body with more impact than the other side resulting in the body sliding in the direction of the side of lesser impact.
From the description and illustration of the present invention it is obvious that it provides many important advantages which can be utilized effectively by virtue of the unique construction of the ellipsoidal-shaped body.
The foregoing description is to be clearly understood to be given by way of illustration and example only, that the spirit and scope of the present invention being limited solely by the appended claims. | A rocking lounge chair for children comprising a generally ellipsoidal shaped body particularly adapted for rocking on a ground surface. A body rest formed into a back, seat and leg rest for a child to recline in a comfortable position thereon is fixedly suspended downwardly within a rectangular opening in the top surface. A bumper guard spaced from the ground surface extends around the lower surface to provide the means for limiting rocking of the body in any position. | 0 |
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/063,697, filed Oct. 14, 2014, the entirety of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a method for reducing polymer fouling or agglomeration, and its use in an acrylate, methacrylic acid, or a methacrylate process. According to the present invention, the reagent comprises an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, or a phthalic acid, and applying the reagent to an acrylate, methacrylic acid, or a methacrylate process to prevent polymeric foulant precursors from agglomerating or to dissolve existing polymeric agglomerates and/or foulants to reduce polymer agglomeration or fouling in the process or storage equipment.
BACKGROUND OF THE INVENTION
[0003] In the acetone cyanohydrin-methyl methacrylate (ACH-MMA) process, acetone cyanohydrin is added to an excess of sulfuric acid (1.4-1.8 mol/mol ACH), which acts as both reactant and solvent. The reaction between ACH and sulfuric acid produces α-sulfatoisobutyramide, which then undergoes an elimination reaction under the heated process conditions to give methacrylamide sulfate.
[0000]
[0004] In the next stage, sulfuric acid serves as catalyst in a combined hydrolysis/esterification of the methacrylamide sulfate to a mixture of MMA and methylacrylic acid (MAA).
[0000]
[0005] In one scheme, the methacrylamide sulfate is reacted with aqueous methanol in a continuous reactor or a series of reactors at temperatures of from 100 to 150° C.
[0006] In the industrial process for the manufacture of methyl methacrylate (MMA), an aqueous sulfuric acid waste stream (spent acid) is produced. This spent acid stream is concentrated with sulfuric acid (H 2 SO 4 ), ammonium bisulfate (NH 4 .HSO 4 ) and residual organic components. The organic components generally comprise a high proportion of residues and tars and smaller quantities of lighter organic compounds.
[0007] Due to the highly contaminated nature of MMA spent acid, the current industrial treatment method available for acid recovery and concentration is that involving regeneration. In this process, the spent acid is decomposed in a brick-lined furnace at about 1000° C. At this temperature, the organic components in the spent acid are oxidized to carbon dioxide and water, the ammonium salts are converted to nitrogen and sulfur dioxide; and the sulfuric acid is reduced to sulfur dioxide. The sulfur dioxide gas stream produced in the regeneration process passes through heat recovery and gas cleaning processes before being converted to sulfuric acid in a conventional contact acid plant.
[0008] Polymerization of MMA, MAA, methacrylamide or other vinyl monomers is undesirable and very common in the manufacturing processes for preparing an acrylate, methacrylic acid, or a methacrylate monomer. In the MMA manufacturing process, polymers formed from MMA, MAA, and other vinyl monomers flow out of the process with the spent acid. Many of the polymers formed have a lower density than the spent acid, so they float in the aqueous acid and when they agglomerate, precipitate out of the spent acid, or deposit on the equipment, they can cause process operating problems.
[0009] Polymer formation, agglomeration, and fouling are generally a concern for the processes for handling an acrylate, methacrylic acid, or a methacrylate monomer. A sulfuric acid-containing waste stream often carries the polymer. Reducing or preventing the operation problems and disposing of the waste stream are challenging and costly goals.
[0010] A method for removing these polymer agglomerates or deposits once they form and for preventing agglomeration or deposition of the polymers before they are formed is a need for the process.
SUMMARY OF THE INVENTION
[0011] One aspect of the invention is a method of dispersing or dissolving a hydrocarbon foulant in a process fluid in contact with processing equipment for preparation of an acrylate, methacrylic acid, or a methacrylate monomer comprising contacting the foulant with an effective amount of an organic solvent, the organic solvent comprising an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, a phthalic acid, or a combination thereof.
[0012] Another aspect is a composition comprising aqueous sulfuric acid, an organic solvent, and a polymer of acrylic acid, an acrylate, methacrylic acid, methacrylamide, or a methacrylate, or a combination thereof, wherein the organic solvent comprises a structure of Formula 1
[0000]
[0000] wherein R 1 and R 2 are independently hydrogen, alkyl, alkaryl, or aryl.
[0013] Other objects and features will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic of the equipment used in a typical methyl methacrylate process.
[0015] Corresponding reference characters indicate corresponding parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The present invention is directed to a method of dispersing or dissolving polymer foulants produced in the process for preparing an acrylate, methacrylic acid, or a methacrylate monomer. Polymers of acrylic acid, an acrylate, methacrylic acid, a methacrylate, a methacrylamide, or other vinyl monomers form as side products. The polymer can become insoluble and then precipitate out of a process stream. The polymer precipitate could deposit on process equipment surface as foulant or agglomerate into large pieces of polymer which can precipitate and separate out of process fluid and adversely affect process operation. The method of the invention disperses or dissolves the insoluble polymer agglomerate in a liquid process stream. Dimethyl phthalate was found to be an effective solvent for polymer agglomerate in a spent acid stream of the methyl methacrylate process. Thus, one advantageous aspect of the method is using a solvent of Formula 1 to reduce or prevent polymer agglomeration or to dissolve an existing polymer agglomerate into a free-flowing liquid and thereby reduce the polymer deposition or fouling of the process equipment.
[0017] One aspect of the present invention is directed to a method of dispersing or dissolving hydrocarbon foulants in a process fluid in contact with processing equipment for preparing an acrylate, methacrylic acid, or a methacrylate monomer comprising contacting the foulants with an effective amount of an organic solvent, the organic solvent comprising an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, a phthalic acid, or a combination thereof.
[0018] The processing equipment can be for the preparation of methyl methacrylate. Preferably, the processing equipment for preparation of methyl methacrylate is adapted to the acetone cyanohydrin process.
[0019] The method described herein wherein the process fluid comprises sulfuric acid or its ammonium salt.
[0020] The process fluid can comprise an acrylate, methacrylic acid, or a methacrylate, or a combination thereof. Preferably, the process fluid comprises methyl methacrylic acid, methyl methacrylate, or a combination thereof.
[0021] The hydrocarbon foulant can be an oligomer or a polymer of acrylic acid, an acrylate, methacrylic acid, a methacrylate, a methacrylamide, or a combination thereof. Preferably, the hydrocarbon foulant comprises an oligomer or a polymer of methacrylamide, methacrylic acid, methyl methacrylate, or a combination thereof.
[0022] The method described herein wherein the organic solvent comprises a structure of Formula 1
[0000]
[0000] wherein R 1 and R 2 are independently hydrogen, alkyl, alkaryl, or aryl.
[0023] Another aspect of the invention is a composition comprising aqueous sulfuric acid, an organic solvent, and a polymer of acrylic acid, an acrylate, a methacrylate, methacrylic acid, methacrylamide or a combination of thereof, wherein the organic solvent comprises a structure of Formula 1
[0000]
[0000] wherein R 1 and R 2 are independently hydrogen, alkyl, alkaryl, or aryl.
[0024] The method or composition wherein R 1 and R 2 are independently hydrogen and C 1 -C 12 alkyl.
[0025] The method or composition described herein wherein the organic solvent comprises phthalic acid, monomethyl phthalate, monoethyl phthalate, monononyl phthalate, monododecyl phthalate, monoundecyl phthalate, dimethyl phthalate, diethyl phthalate, dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, monophenyl phthalate, monobenzyl phthalate, diphenyl phthalate, dibenzyl phthalate, or a combination thereof.
[0026] The method or composition wherein the organic solvent comprises dimethyl phthalate, diethyl phthalate, dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, or a combination thereof.
[0027] The method or composition described herein wherein the organic solvent comprises dinonyl phthalate, didodecyl phthalate, diundecyl phthalate, or a combination thereof.
[0028] The method or composition wherein the organic solvent is dimethyl phthalate, diethyl phthalate, or a combination thereof.
[0029] The method or composition wherein the organic solvent comprises dimethyl phthalate.
[0030] The method wherein the hydrocarbon foulant is an oligomer or polymer of ethylenically unsaturated or vinyl monomers.
[0031] The method wherein the hydrocarbon foulant is an oligomer or polymer of acrylic acid, an acrylate, a methacrylate, methacrylic acid, a methacrylamide, or a combination thereof.
[0032] The method described herein wherein the organic solvent concentration in the fluid is from about 10 ppm by weight to about 1% by weight.
[0033] The method wherein the organic solvent concentration is from about 100 ppm to about 1000 ppm when the organic solvent is used to disperse or prevent hydrocarbon foulant from agglomeration, precipitation, or deposition.
[0034] The method described herein wherein the organic solvent is added to the process fluid continuously.
[0035] The method wherein the organic solvent concentration is from about 100 ppm by weight to about 15% by weight when the organic solvent is used to dissolve or remove the hydrocarbon foulant.
[0036] The method wherein the organic solvent is added to the process fluid intermittently.
[0037] The method described herein further comprising a chemical additive, the chemical additive being a second solvent, a dispersant, a polymerization inhibitor, or a combination thereof.
[0038] The method described herein where the second solvent comprises, tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), methylene dichloride, or a combination thereof.
[0039] The polymerization inhibitor can comprise a phenolic compound, a phenylenediamine or a derivative thereof, a phenothiazine or a derivative thereof, a nitrosophenol or a derivative thereof, a nitroxide or a derivative thereof, a hydroxylamine, or a combination thereof.
[0040] FIG. 1 shows the reactor 10 , the spent acid stream 30 , the spent acid storage tank 50 , the spent acid recovery unit 70 , and the several places that the organic solvent could be added to the process. In particular, the organic solvent can be added the spent acid storage tank circulation stream 60 . Additionally, the organic solvent can be added to the spent acid reactor bottoms stream 30 at injection point 40 in order to treat the stream before it reaches the acid regeneration unit or the spent acid storage tank. Finally, the organic solvent can be added to the reactor inlet 20 or if there is more than one reactor in the system, in between the reactors in order to prevent the agglomeration or deposition of the polymer in the processing system.
[0041] The organic solvent can be added to the processing system continuously or intermittently in order to provide a spent acid stream that does not contain a solid polymer that precipitates out of the process fluid or deposits on the equipment. The organic solvent can be added into one or more of the streams in order to maintain a flowing polymer stream within the spent acid stream.
[0042] Unless otherwise indicated herein, an “acrylate” is a salt or ester of acrylic acid.
[0043] Unless otherwise indicated herein, a methacrylate” is a salt or ester of methacrylic acid.
[0044] Having described the invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims.
EXAMPLES
[0045] The following non-limiting examples are provided to further illustrate the present invention.
Example 1
Dimethyl Phthalate Prevents Polymer from Agglomeration/Precipitation
[0046] In a typical methyl methacrylate plant, polymer tends to precipitate out of a spent acid process stream and form solid polymer agglomerate. The polymer agglomerate globules float on the surface of the spent acid stream, and cause operation problems and require cleaning and disposal costs.
[0047] The following experiment shows that an organic solvent treatment can prevent the polymer agglomeration or precipitation.
[0048] A concentrated polymer solution was prepared by dissolving a piece of solid methyl methacrylate process polymer in a THF solvent. In a test tube with 10 mL of spent acid liquid (an aqueous sulfuric acid waste stream from a methyl methacrylate process), an aliquot of the concentrated polymer solution was added. In an untreated test, upon addition and mixing, the polymer immediately precipitated out of the liquid and turned into a piece of solid polymer floating on the top of the liquid, which was consistent with operational experience. In a treated test, the spent acid liquid sample was dosed with dimethyl phthalate prior to adding the polymer solution. In contrast, agglomeration/precipitation did not occur upon addition of the polymer solution. Instead, the polymer was fully dispersed in the liquid with agitation (after shaking), and then the polymer gradually separated out as a liquid layer at the top of the liquid after settling. The liquid layer was easily redispersed in the spent acid with agitation thereafter. This evidence shows that a dimethyl phthalate treatment was able to keep the polymer from agglomeration or precipitation in an acidic process stream and thus protect process equipment from polymer fouling.
[0049] In the above experiment, a large group of candidates were screened. None of them were truly able to prevent polymer precipitation out of the spent acid though some of the organic solvents were able to dissolve the polymer. Dimethyl phthalate was preferred.
Example 2
Dissolution Study
[0050] This experiment demonstrated that the organic solvent was also capable of dissolving an existing solid polymer in the spent acid environment. In this experiment, a solid piece of the spent acid storage tank polymer was dropped in a solution of the spent acid and was agitated on a stirrer for 4-6 hours and then left to settle. In a treated sample, dimethyl phthalate was dosed and compared with an untreated sample (not treated with any additives) and a commercial dispersant treated sample.
[0051] The solution treated with dimethyl phthalate was much darker than the untreated or the dispersant treated solution, indicating a noticeable dissolution of the polymer into the spent acid solution. In addition, the solid polymer became soft after soaking in the dimethyl phthalate treated solution for two to three days, whereas the other two polymer samples (e.g., the untreated sample and the dispersant treated sample) remained intact. These results showed that dimethyl phthalate was an effective solvent for spent acid storage tank polymer, and was a potential cleaning solvent for removal of a polymer deposited on operation equipment.
[0052] When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
[0053] In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
[0054] As various changes could be made in the above methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | The present invention generally relates to a method for reducing polymer agglomeration or fouling, and its use in processes for the preparation of an acrylate, methacrylic acid, or a methacrylate. According to the present invention, the reagent comprises an alkyl phthalate, an alkaryl phthalate, an aryl phthalate, or a phthalic acid, and applying the reagent to processes for the preparation of an acrylate, methacrylic acid, or a methacrylate to prevent polymeric foulant precursors from agglomerating or to dissolve existing polymeric agglomerates or foulants so as to reduce polymer agglomeration or fouling in the process or storage equipment. | 2 |
The present application claims priority from PCT Patent Application No. PCT/EP2010/061993 filed on Aug. 17, 2010, which claims priority from German Patent Application No. DE 10 2009 037 543.0 filed on Aug. 17, 2009, the disclosures of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns a digital wireless audio transmission system and a method of wireless audio transmission.
2. Description of Related Art
Analog wireless microphone systems are known in which a search is made for free frequency channels for transmission of the audio signals recorded by the microphone units. If a channel is suffering interference then it is possible to use a new undisturbed channel and audio transmission can then occur by way of that new channel.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an improved digital wireless microphone system which can be operated in an environment suffering from interference sources.
Thus there is provided a digital wireless audio transmission system. The system has at least one wireless digital microphone unit for the wireless transmission of audio signals based on adjustable transmission settings and parameters. The audio transmission system further has a central unit which has a monitor unit for monitoring and analyzing a frequency spectrum of an available frequency band, a link adaptation unit for adapting the transmission settings and transmission parameters of the wireless transmission of the microphone unit based on the results of the monitor unit, and at least one transmitting/receiving unit for receiving audio signals to be transmitted wirelessly of the at least one microphone unit and for transmitting transmission settings and transmission parameters by way of a return channel to the microphone unit. The transmission settings and transmission parameters of the wireless transmission of the wireless microphone unit are modified in accordance with the transmission settings and parameters transmitted by way of the return channel. The transmission settings and parameters transmitted by way of the return channel have a center frequency of a channel, a selection of a modulation method and parameters of the modulation method, a data rate and/or channel encoding.
In an aspect of the present invention the microphone unit has a first analysis unit for monitoring and analyzing the frequency spectrum of the available frequency band and a second analysis unit for monitoring and analyzing the wireless transmission from or to the at least one wireless mobile unit. It is thus possible to monitor both the wireless transmission to and from the wireless mobile unit and also the frequency spectrum.
In a further aspect of the invention the link adaptation unit has a modulation selection unit for selection of a modulation method and modulation parameters based on the results ascertained by the monitor unit, a data rate selection unit for selection of a data rate based on the results of the monitor unit, a channel encoder selection unit for selection of a channel encoding based on the results of the monitor unit, an audio encoder selection unit for selection of an audio encoding based on the results of the monitor unit, a channel distribution unit for distribution of the data transmission to various channels based on the results of the monitor unit and a link setting unit for setting the transmission settings and transmission parameters based on the results of the monitor unit.
In a further aspect of the invention the audio transmission system comprises a position information unit having a position determining unit for determining the position of the central unit and a database unit. The database unit has frequency band information associated with the position information. A selection of the available frequency bands can be effected based on the position information.
The invention concerns the notion of providing a digital wireless audio transmission system having at least one wireless microphone and a receiving unit. The receiving unit monitors or detects the transmission parameters and properties of the wireless audio transmission from the microphone units to the receiving units. If one of the parameters or transmission properties falls below a limit value then the receiving unit can initiate adaptation or modification of the wireless digital link or connection. In that way the digital wireless audio transmission system can be automatically adjusted to new ambient situations.
As an alternative to the wireless microphone it is also possible to provide a wireless pocket transmitter or an in-ear monitor unit in the audio transmission system.
Further configurations of the invention are subject-matter of the appendant claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a diagrammatic view of a digital wireless microphone system according to a first embodiment;
FIG. 2 shows a detained diagrammatic view of a central unit of the wireless microphone system of FIG. 1 ; and
FIG. 3 shows a view of the transmission in the case of a wireless digital audio transmission system according to a fifth embodiment.
DETAILED DESCRIPTION OF EMBODIMENTS
It is to be understood that the figures and descriptions of the present invention have been simplified to illustrate elements that are relevant for a clear understanding of the present invention, while eliminating, for purposes of clarity, many other elements which are conventional in this art. Those of ordinary skill in the art will recognize that other elements are desirable for implementing the present invention. However, because such elements are well known in the art, and because they do not facilitate a better understanding of the present invention, a discussion of such elements is not provided herein.
The present invention will now be described in detail on the basis of exemplary embodiments.
FIG. 1 shows a diagrammatic view of a digital wireless audio transmission system according to the first embodiment. In this case the audio transmission system is in the form of a wireless microphone system. The digital wireless microphone system has a central unit 10 and a plurality of mobile units in the form of wireless microphone units 400 . The wireless microphone units 400 record or detect audio signals and implement digital wireless audio transmission to the central unit 10 . That is effected by the wireless channel AK (for example an HF channel). In addition provided between the central unit 10 and the microphone units 400 is a respective return channel RK, by way of which items of control information or an instruction for modification of transmission parameters can be transmitted from the central unit 10 to the microphone units 400 .
The central unit 10 has a monitor unit 100 for monitoring the digital wireless transmitting/receiving environment, a link adaptation unit 200 for adapting the wireless link, a wireless transmitting/receiving unit 500 and optionally a position information unit 300 .
The monitor unit 100 serves to implement analysis of the environment of the central unit for example in respect of frequency occupancy, the presence of interference sources in a frequency band, the bandwidth of the available channels and the like. The monitor unit 100 can also be adapted to perform an analysis of the received signals from the microphone units 400 as well as the parameters or settings of the audio transmission from the microphone units 400 .
The link adaptation unit 200 serves, in dependence on the items of information detected by the monitor unit 100 to possibly perform adaptation of the transmission channel or the parameters or settings of the transmission from the wireless microphone units. The transmitting/receiving unit 500 serves to receive the audio signals transmitted from the microphone units 400 . The transmitting/receiving unit also has a return channel transmitting unit for the transmission of items of information (transmission settings and transmission parameters) from the central unit 10 to the respective microphone units 400 by way of a return channel.
Optionally the position information unit 300 can perform a position determining operation and can pass onward items of information in respect of the instantaneous position of the link adaptation unit 200 .
The monitor unit 100 detects the parameters of a frequency spectrum within a frequency band available for wireless digital audio transmission. In that respect it is possible to detect suitable frequency channels and interference sources within the frequency band. In dependence on those detected items of information, a modification to the transmission settings or parameters of the digital wireless transmission between the wireless microphone units and the central unit 100 can be performed in the link adaptation unit 200 . In that case for example the modulation method, the stepping configuration of the modulation method, the data rate, the channel encoding, the audio encoding and/or the channel occupancy can be influenced or adapted.
FIG. 2 shows a detained diagrammatic view of the central unit 10 in accordance with a second embodiment. In this case the central unit 10 in accordance with the second embodiment can be based on the central unit 10 in accordance with the first embodiment.
The central unit 10 has a monitor unit 100 , a link adaptation unit 200 , a transmitting/receiving unit 500 and optionally a position information unit 300 . The monitor unit 100 has a first analysis unit 110 for analysis of the frequency environment and a second analysis unit 120 for analysis of the audio signals transmitted from the microphone units 400 . In the first analysis unit 110 , the quality of the available frequency spectrum in the allowed frequency band can be monitored and analyzed. In that case for example the available frequency channels inclusive of the bandwidth thereof can he determined. In addition the interference sources in the frequency band can be detected. That analysis of the frequency spectrum can be effected continuously or at predetermined moments in time. The wireless microphone system can be brought into coincidence with modifications in the frequency spectrum by continuous analysis of the latter.
The link adaptation unit 200 can have a modulation selection unit 210 , a data rate selection unit 220 , a channel encoder selection unit 230 , an audio encoder selection circuit 240 , a channel distribution unit 250 and a link setting unit 260 . The modulation selection unit 210 serves in that case to make a selection of the modulation method based on the results of the monitor unit 110 . In that respect it is possible to use various modulation methods such as for example single-carrier or multi-carrier methods, FSK, MSK, PSK or the like. In addition the number and spacing of the subcarriers in the case of multi-carrier modulation methods can be adjusted. Furthermore the stepping nature of a modulation method such as for example 64 QAM, 16 QAM can be adjusted. In that case the selection of the modulation method is effected in dependence on the results of the first analysis unit 110 .
The data rate selection unit 220 serves for selection of a data rate for the wireless transmission in dependence on the results of the first analysis unit 110 . The channel encoder selection unit 230 serves for the selection of channel encoding in dependence on the results of the first analysis unit 110 . The audio encoder selection unit 240 serves for the selection of audio encoding for the wireless transmission in dependence on the results of the first analysis unit 110 . The channel distribution unit 250 serves for the distribution of available channels in the case of digital wireless audio transmission in dependence on the results of the first analysis unit 110 . The link setting unit 260 serves for setting the parameters of the link for the digital wireless audio transmission in dependence on the selection of the modulation selection unit 210 , data rate selection unit 210 , channel encoder selection unit 230 , audio encoder selection unit 240 and channel distribution unit 250 . The settings and parameters set by the link setting unit 260 can then be transmitted by means of the transmitting/receiving unit 500 to the wireless microphone units 400 which then perform their wireless audio transmission in corresponding fashion.
The transmitting/receiving unit 500 has a wireless receiving unit 510 for receiving the audio signals transmitted from the wireless microphone units and a return channel transmitting unit 520 for transmitting settings and parameters for a change in the transmission parameters.
Optionally there can be a position information unit 300 . The position information unit 300 can have a position determining unit (GPS) 310 and database 320 . The database 320 has items of information in respect of the available frequency bands in relation to the respective positions. Those items of information can then be used by the link adaptation unit 200 to select frequencies only within the permitted frequency band.
The quality of the frequency spectrum and the appropriate frequency channels can be continuously and dynamically monitored in the monitor unit 100 . Monitoring of the currently prevailing link quality can also be effected. If the currently prevailing link quality falls below a fixed limit value adaptation of the wireless transmission link can then be effected. In that case the link adaptation unit 200 determines which of the parameters and settings of the wireless audio transmission have to be modified so that the link quality is above a previously established limit value. The items of information in respect of a modification to the transmission link can be communicated to the wireless microphone units 400 for example by the return channel transmitting unit 520 . That can be effected for example on the basis of dedicated log-in and log-out frames.
Various methods of adapting the transmission link can be combined in the link adaptation unit 200 . If for example there are a plurality of frequency channels with slight interference so that it is no longer possible to communicate in error-free fashion with a higher-value kind of modulation such as for example 16 QAM, then the data can be distributed for example to two different frequency channels and transmitted in error-free fashion with a lower modulation stepping (for example QPSK). The data from the two channels can then be suitably brought together in the central unit 10 .
If for example there are a plurality of interference-affected channels then transmission can be effected by way of all interference-affected channels. An intelligent combination of all data transmitted by way of the interference-affected. channels can then be effected in the central unit. It is possible in that way to achieve an improved signal-to-noise ratio, whereby higher-grade modulation is possible.
If however the signal-to-noise ratio falls then an adapted audio encoding can be effected with a reduced channel data rate to permit robust transmission. Robust transmission can then permit error-free transmission with a higher level of audio compression. Optionally it is also possible to accept lossy encoding of the audio signals if sufficient transmission capacities are not present.
If for example there is a channel without interference then wireless audio transmission from the microphone units to the central unit can be at least temporarily implemented by way of that undisturbed channel.
The monitor unit 100 can also be adapted to perform a quality-of-service QoS identification. A quality-of-service setting can be associated with each microphone unit so that the various microphone units can be associated with differing prioritization. Thus for example the microphone for a lead singer can have or be attributed with a higher quality-of-service setting than the microphones for example for background singers. In that way the audio signals from the microphone of the lead singer are transmitted with a higher level of prioritization than for example audio signals from other singers.
The return channel RK can be used for example robustly and on a world-wide basis (for example in the ISM band).
When for example it is found that a signal-to-noise ratio is below a limit value on a given channel so that it is no longer possible to embody a higher data rate, it is possible by means of the wireless digital microphone system according to the invention to switch over the stepping of the modulation method for example from 64 QAM to 16 QAM. In that way the data rate is reduced to 25%. If however for example on the basis of the first analysis unit 110 it has been found that one or more data channels is or are available, then the data stream can be distributed to the two data channels, in which case the transmission parameters or settings on the two channels can be different.
The selected setting parameters are also transmitted in the audio transmission. so that the separate data streams can be brought together again in the central unit 10 .
Different setting parameters, modulation methods, steps of the modulation method, data rate, channel encoding and/or audio encoding can be selected on the selected channels. In other words, transmission on one channel can be different from transmission on another channel. It is important in that respect that optimum setting of the parameters is implemented for each channel.
Preferably the selection of the channels and the selection of the transmission parameters is effected by the central unit 10 , in particular by the link adaptation unit 200 based on the results of the first analysis unit 110 .
Preferably the center frequency or medium frequency of the transmission, the data rate and the channel encoding as well as the modulation method are transmitted to the wireless microphone units by way of the return channel by means of the return channel transmitting unit 520 so that they can be set to those setting parameters and can suitably perform wireless digital transmission.
The first analysis unit 110 is adapted to check the occupancy of the various frequency channels in the available frequency band. That can also include detection of the bandwidths of the various channels.
The second analysis unit 120 is adapted to detect and evaluate the signals from the respective wireless microphone units 400 . That can involve for example detection of the signal-to-noise ratio. In addition further parameters or settings of the audio transmission can be detected. It is possible in that respect for example also to monitor whether the respective microphone units 400 have been set to the predetermined center frequencies, modulation method, data rate, channel encoding, audio encoding or the like, which have been predetermined by the link adaptation unit 200 . Accordingly it is possible to provide for monitoring of the presets. A microphone unit can display whether it has implemented the required adjustments, by means of the log-off and log-on frames.
In a configuration of the present invention the audio signals to be transmitted from the wireless microphone units can be distributed to a channel or a plurality of channels. Transmission by way of the respective channels can then be suitably controlled by the link adaptation unit 200 , in which case the parameters and settings of the transmission by way of the respective channels are adapted to the circumstances of the respective channels.
Upon distribution of the data to different channels for example the data rate on the respective channels can be reduced. The reduced data rate then depends on the number of channels. As an alternative thereto the same data can be transmitted by way of a plurality of channels. The data received by way of the various data channels can be intelligently brought together in the central unit 10 . In that way it is possible to guarantee a transmission even if the respective data channels are faulty. Error-free data reception can be first ensured by the data received by way of the various data channels being intelligently brought together.
Although FIG. 1 only shows one transmitting/receiving unit there can be a plurality of transmitting/receiving units 500 . Those receiving units can be part of the central unit 10 or can be connected to or coupled to the central unit 10 . For example there can be a dedicated return channel for each transmitting/receiving unit.
In a second embodiment of the invention implementation of the changes to the transmission settings and parameters can be carried out in the microphone unit itself. With a falling link quality the microphone can re-set the settings and link parameters, based on the results of the monitor unit which are transmitted to the microphone by way of the return channel. That can then be communicated to the receiving unit so that it can make suitable adjustments.
In a third embodiment which can be based on the first or second embodiment there can be a wireless digital pocket transmitter, in addition to or alternatively to the wireless microphone units. The wireless pocket transmitter can receive audio signals by way of a further microphone and can then transmit them to the central unit. Thus there can be provided an audio transmission system in which there are provided wireless microphone units and/or wireless pocket transmitters.
In the foregoing embodiments, reference was made to a microphone unit. The foregoing embodiments however also apply to a pocket transmitter at which there is no microphone but which receives an audio signal at its input.
In a fourth embodiment which can be based on the first, second or third embodiment there is a wireless digital in-ear monitor unit as a mobile unit. The wireless in-ear monitor unit receives audio signals from a central unit 10 and can output those audio signals to the user for example by way of an earpiece. In the fourth embodiment there is also a return channel between the mobile wireless in-ear monitor units and the central unit. In that respect the design configuration and control of the return channel can optionally correspond to the design configuration and control of the return channel in accordance with the first, second or third embodiment. Alternatively thereto the design configuration and control of the return channel can be provided in such a way that the return channel is only used to implement a handshake mechanism. In that way the in-ear monitor unit would only confirm for example a change to the frequency by way of the return channel.
As an alternative to the above-described embodiments there can be a central unit or a central device connected to the central units or the transmitting/receiving units. That central device can centrally predetermine the settings or parameters of the wireless audio transmission. That can also be implemented for example by a plurality of transmitting/receiving units 500 being provided in the central unit or connected to the central unit.
In contrast thereto in an autonomous approach adjustment of the transmission settings and parameters can be effected separately for each transmission section. In such a situation the microphone unit or pocket transmitter can itself perform the modification of the transmission settings or transmission parameters for the separate transmission section.
In a further embodiment of the invention a number of transmitting/receiving units can be connected to the central unit and controlled by way of the central unit. In that case there can be a transmitting/receiving unit both for reception of the wireless audio transmission and also for the return channel. Preferably there is a transmitting/receiving unit for each microphone unit or each pocket transmitter.
FIG. 3 shows a view of the transmission in a wireless digital audio transmission system according to a fifth embodiment. The audio transmission system according to the sixth embodiment can be based on an audio transmission system according to the first, second, third or fourth embodiment. Thus wireless transmission is accordingly effected between the central unit 10 and a mobile unit 400 . That transmission can be directed from the mobile unit to the central unit if the mobile unit is in the form of a microphone unit or pocket transmitter. If the mobile unit is in the form of an in-ear monitor unit or camera receiver then wireless transmission can be from the central unit to the mobile unit. The respective return channel is provided in the microphone units or wireless pocket transmitters from the central unit to the mobile units. In the case of the in-ear monitor units the return channel is then provided from the in-ear monitor to the central unit. Alternatively thereto there can be a further return channel from the central unit to the in-ear monitors.
FIG. 3 shows a view in respect of time of the transmitting power of a channel K 1 and a view in respect of time of the transmitting power of the return channel RK. In that case the channel K 1 can be implemented both from the mobile units to the central unit and also from the central unit to the mobile units.
While the main channel K 1 is adapted for transmission of the useful signal (audio signal) from the mobile units to the central unit 10 (the mobile units are in the form of wireless microphone units or wireless pocket transmitters), the return channel is from the central unit to the mobile units. In the fifth embodiment of the invention transmission is effected on the return channel at the same frequency as on the first channel. So that the situation does not involve interference phenomena on that transmission channel the transmission on the first channel K 1 is reduced for a short time or the power P(t) in the first channel is reduced. In return the power at the same moment in time in the return channel RK is increased for the transmission for example from the central unit to the mobile units. Thus transmission is effected by way of the return channel precisely at the time intervals when the transmission by way of the first channel K 1 is reduced or suspended.
The return channel or the return section can serve to transmit parameters of the transmission to the mobile units, that is to say the wireless microphone or the wireless transmitter so that they can be correspondingly modified in the mobile unit. Those parameters can involve synchronization, adaptation of audio amplification, adaptation of the transmitting power, a modulation mode and the source and channel encoding. Accordingly a modification to the parameters of the mobile unit is to be made possible by means of the wireless return section or wireless return channel. Those parameters can involve the time basis (synchronization), audio amplification and parameters for wireless transmission such as for example transmitting power, modulation method and source and channel encoding. The provision of the return channel is intended to improve the reliability of wireless transmission between the mobile units and the central unit by enhancing the reliability of transmission with changing ambient conditions (radio channel, interference phenomena etc.).
In fifth embodiment transmission is effected on the return section or return channel at the same frequency as on the main channel K 1 , between the mobile unit and the central unit. Wireless transmission by way of the main channel can be effected both from the mobile unit to the central unit and also from the central unit to the mobile unit. To permit wireless transmission by way of the main channel and also by way of the return channel at the same frequency transmission can be effected in the time division duplex mode. That involves fixing a frame in which wireless transmission is effected by way of the main channel to transmit the useful data (audio signals). The mobile unit can alternately transmit and receive at the same frequency. That is advantageous as an HF synthesizer can be operated continuously.
The frame lengths in transmission by way of the main channel and in transmission by way of the return channel are of different values and can be determined by the minimum latency of the main channel. The ratio of the time slots for the main channel and the return channel can correspond to the ratio of the symbol rates for the main channel and the return channel. In that respect the symbol rate on the main channel is substantially greater than that on the return channel. The data rates on the main channel and the return channel then correspond to a multiplication of the symbol rates by the number of bits/symbol of the respective modulation mode.
The robustness of the return channel can be increased in relation to the main channel by a selection of the appropriate kind of modulation. In addition a receiver which is required in the mobile unit can be of a simpler design configuration by virtue of a suitable selection of the kind of modulation of wireless transmission with the main channel.
Optionally the reduction in the power on the main channel or the increase in power on the return channel can be effected not abruptly but continuously (as shown in FIG. 3 ). The reduction in power on the main channel and the increase in power on the return channel can be effected in that case in accordance with a cosine-square function. That is advantageous because such a reduction or increase in power can be provided directly in a digital modulator in a transmitter. In particular the transmitting final stage can be completely switched off for the main channel if there is a very low HF level.
If the mobile unit is in the form of a wireless radio microphone the main channel with the audio data section can have a transmitting time of 3 ms and transmission can then be effected with 32 QAM modulation (corresponds to 5 bits/symbol). The return channel or return section can have a transmitting time of 100 μs and can have robust BPSK modulation (corresponds to 1 bit/symbol). The increase and decrease in transmitting power in the main channel and the return channel can take place every 20 μs so that the switching spectrum does not violate the frequency mask. The symbol duration can be of 66 μs, which corresponds to 166.7 ksps in both directions. Accordingly the situation involves a data rate on the main channel (audio data section) of (3 ms−2·20 μs)/6 μs·5 bit/3.1 ms=796 kbit/s. The return section has a data transmission of (100 μs−2·20 μs)/6 μs·1 bit/3.1 ms =3.2 kbit/s. The central unit in the form of a stationary receiver can be synchronized to the transmitted frames of the mobile unit and can thus predict coming uplink time slots and use them for the transmission of signaling data by way of the return channel back to the mobile unit. Updating of frame synchronization can be effected on the basis of the recovered symbol clock. Additionally or alternatively observation of the power ramping which initiates or terminates active time slots can be observed. Signaling or transmission from the mobile unit to the central unit which in the form of a stationary receiver can be effected embedded in the audio data stream. Flow control or handshaking can also be implemented on the basis of the return section or return channel provided in accordance with the embodiments of the invention.
If the mobile unit is in the form of an in-ear monitor unit then optionally there can be a return channel from the central unit to the in-ear monitor unit in the same transmission direction as the main transmission (audio data section).
Remote control of the mobile units can be effected by the provision of the return channel or return section according to the invention. That is advantageous in regard to an improvement in reliability and an improvement in frequency efficiency in wireless audio transmission systems. Asymmetrical time division duplex transmission is proposed in accordance with the fifth embodiment. In this case, the same frequency is used for the return channel as in the main channel. Thus no additional frequency resources are required. The frequency for the wireless transmission means that automatic addressing or distinguishing of the respective transmitters and receivers can also be effected. No additional synthesizer is required in the mobile units as transmission takes place at the same frequency. In addition there is no need for a second radio solution so that there is also a broader space requirement. Furthermore the coexistence problems as between different radio solutions can be avoided in accordance with the invention. In addition the energy consumption in mobile units can be reduced as no further transmitter/receiver is needed. Furthermore it is possible to dispense with an additional antenna in the mobile unit. The channel estimation for the main channel can also be used for the return channel. A frequency change for the avoidance of interference can be initiated in an uplink time slot so that there does not have to be any audio interruption. Scalability of the uplink and downlink data rate can be made possible for different applications by a compromise in respect of latency.
While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the inventions as defined in the following claims. | An audio transmission system including a wireless digital microphone unit which detects audio signals and wirelessly transmits the detected audio signals based on adjustable transmission settings and transmission parameters, and a central unit. The central unit has a monitor unit for monitoring and analyzing a frequency spectrum of an available frequency band, a link adaptation unit which adapts the microphone's transmission settings and parameters based on the results of the monitor unit, and a transmitting/receiving unit for receiving wirelessly transmitted audio signals from the wireless microphone unit and for transmitting transmission settings and transmission parameters via a return channel to the wireless microphone unit. The microphone's transmission settings and parameters are modified based on the transmission settings and transmission parameters transmitted via the return channel, which have a center frequency of a channel, a selection of a modulation method and parameters thereof, a data rate, and/or a channel encoding. | 7 |
RELATED PATENTS
This application is a continuation-in-part of U.S. patent application Ser. No. 08/591,337, filed Jan. 25, 1996, now abandoned.
FIELD OF THE INVENTION
The present invention relates to surgical fasteners. More particularly, the present invention relates to improved surgical fasteners of the type which are secured by surgical applicators. In even greater particularity, the present invention relates to improvements in surgical staples and clips.
BACKGROUND OF THE INVENTION
Surgical fasteners, including clips and staples, and methods of applying these fasteners are well known in the art. Surgical fasteners can be used to close incisions or wounds, or to clamp vessels or ducts to prevent fluid flow. Surgical applicators used to apply these fasteners comprise various designs depending on the use to which the fasteners are employed. For example, a clip applicator is typically a pistol-shaped vise used where a vessel or duct must be sealed. The clip is directed to the location of application and then the vise secures the clip, collapsing and sealing the vessel. A surgical stapler is typically used where an incision or wound must be closed. A surgical stapler typically employs an anvil to form the fastener during application. With increasing use and improvement of various surgical applicators, fasteners have also improved. Some examples of surgical fasteners are found in U.S. Pat. Nos. 4,407,286; 4,489,875; and 4,932,960.
In the '286 patent, Noiles et al. disclose a surgical staple which is designed to reduce the tendency of the staple to slip off the anvil during application or to adhere to the anvil after application. In the '875 patent, Crawford et al. disclose a self-centering staple to remedy the problem of misalignment of the staple during application. In the '960 patent, Green et al. disclose a bioabsorbable fastener designed for elastic expansion to prevent breakage. Although the foregoing surgical fasteners, as well as others known in the art, have addressed and remedied many problems encountered with the use of these fasteners, there still exist problems accompanying their use.
One such problem is the slippage of fasteners at the point of their application in the tissue. During surgery it is frequently required to shut off fluid transfer to areas, thus fasteners are often placed around blood vessels or other structures to achieve this. For example, in cases where polyps are to be removed, fasteners are typically applied to the base of the structure to shut off fluid transfer and the polyp is removed. The fastener is left in place during the healing process to prevent fluid loss. As hydrostatic pressure increases due to the blockage, fasteners tend to slip away from the pressurized area which can result in fastener displacement and fluid loss or hemorrhage. Another problem seen with currently used fasteners concerns the closure of the fastener itself. During application of the fastener, the typical U or V-shaped designs often result in non-uniform closure of the fastener over the vessel, which again can lead to fastener displacement as well as fluid loss or hemorrhage. To avoid these problems, the fastener is tightly fastened into the tissue encompassed by the fastener, which still does not guarantee against slippage. In addition, in surgeries where fasteners are employed to temporarily shut off blood flow through a vessel, this form of application can cause irreparable injury to the vessel.
From the foregoing it may be seen that a need exists for an improved surgical fastener which is designed to resist displacement once secured to the tissue.
SUMMARY OF THE PRESENT INVENTION
It is the object of the present invention to provide an improved surgical fastener of the type used in surgical applicators which resists displacement once secured to the tissue.
It is another object of the present invention to provide a fastener which can be used in surgical applicators presently available.
These and other objects of the present invention are accomplished through the use of a surgical fastener which has been modified to enhance the gripping capability of the fastener once secured. The fastener can have apertures therethrough or the surface can be knurled, crimped, etched with a laser, layered with an abrasive coating, sand blasted, punched, notched, or modified in any other manner which enhances the grip of the fastener when secured. Additionally, the fastener can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. For purposes of this disclosure, a knurled surface refers to a surface which has been roughened to provide an enhanced grip. Examples of knurling include serrations, dimples, protrusions, cross-hatches, grooves, and flutes pressed into a surface. The abrasive coating is a material such as non-toxic paint containing a plurality of solid particles wherein these particles form protrusions in the coating once applied to the fastener. The modification can be continuous over the entire surface of the fastener or it can be only on the tissue contacting surface, and can additionally have modified regions intermixed with unmodified regions. During the application of the fastener to the target tissue, the tissue conforms to the modified surface of the fastener. This results in resistance to slippage because the fastener surface presses into the tissue causing depressions in the tissue. Subsequently, tissue edema and growth encapsulates and integrates into deformities in the fastener. An alternate embodiment includes a double wall to reinforce the fastener when secured.
These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
A surgical fastener embodying features of my invention is described in the accompanying drawings which form a portion of this disclosure and wherein:
FIG. 1 is a perspective view of a square-cornered U-shaped fastener before application.
FIG. 2 is a perspective view of the fastener of FIG. 1 where the surface has been knurled with a cross-hatch design.
FIG. 3 is a perspective view of the fastener of FIG. 1 where the surface is dimpled.
FIG. 4 is a perspective view of the fastener of FIG. 1 where the surface has protrusions.
FIG. 5 is a perspective view of the fastener of FIG. 1 where the surface has linear grooves or flutes.
FIG. 6 is a perspective view of the fastener of FIG. 1 where the surface has curvilinear grooves or flutes.
FIG. 7 is a perspective view of the fastener of FIG. 1 where the surface has been etched with a laser.
FIG. 8 is a perspective view of the fastener of FIG. 1 where the surface has been layered with an abrasive coating.
FIG. 9 is a perspective view of the fastener of FIG. 1 where the fastener has apertures therethrough.
FIG. 10 is a perspective view of the fastener of FIG. 1 where the fastener has been crimped.
FIG. 11 is a perspective view of the fastener of FIG. 1 where the edges of the fastener have been notched.
FIG. 12 is a perspective view of the fastener of FIG. 4 clamped around a blood vessel to prevent fluid transfer.
FIG. 13 is a perspective view of the fastener of FIG. 4 secured into tissue for maintaining closure of an incision.
FIG. 14 is a perspective view of an alternate embodiment showing a linear shaped fastener before application.
FIG. 15 is a perspective view of an alternate embodiment showing a V-shaped fastener before application.
FIG. 16 is a perspective view of an alternate embodiment showing an alternate U-shaped fastener before application.
FIG. 17 is a perspective view of an alternate embodiment showing an alternate U-shaped fastener before application.
FIG. 18 is a perspective view of an alternate embodiment showing a C-shaped fastener before application.
FIG. 19 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner V-shaped portion before application.
FIG. 20 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner U-shaped portion before application.
FIG. 21 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner oval-shaped portion before application.
FIG. 22 is a perspective view of an alternate embodiment showing a double-walled fastener having an alternate inner V-shaped portion before application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A more complete understanding of the invention may be obtained by reference to the accompanying drawings wherein the fastener, according to the embodiment illustrated in FIG. 1, is a square-cornered U-shaped member 10 having a base 11 and at least two parallel legs 12. The preferred embodiment is composed of titanium or stainless steel, although other metals, plastics, or ceramics can be used, as well as malleable wire. The preferred embodiment has a square cross-section, although the cross-section can be round or have any polygonal shape. Other embodiments of the present invention include a linear shaped member shown in FIG. 14, a V-shaped member shown in FIG. 15, other U-shaped members shown in FIG. 16 and FIG. 17, or a C-shaped member shown in FIG. 18. Another beneficial feature is a novel double wall, which acts to reinforce the fastener when secured. Embodiments of the present invention illustrating the double wall feature are shown in FIGS. 19-22, discussed in further detail hereinbelow. The embodiment of choice can depend on the personal preference of the user as well as the procedures for which the fasteners are to be used.
Typically, fasteners embodying features of my invention are formed from a sheet, or wire, of titanium or stainless steel which has been modified with a texturizing feature. Moreover, the fasteners can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. The sheets or wires are pulled from preformed rolls having a thickness usually between 0.015 to 0.025 inches. As the sheet or wire is pulled from the roll, it is pulled though a device for texturizing the sheet or wire. This texturizing device can be a crimping mechanism for crimping the sheet or wire; a knurling mechanism for pressing serrations, dimples, protrusions, cross-hatches, grooves, or flutes into the surface of the sheet or wire; an applicator for applying a non-toxic abrasive coating containing a plurality of solid particles to the surface of the sheet or wire; a series of lasers for etching into, or forming apertures through, the sheet or wire; a sand blasting chamber for pitting the surface of the sheet or wire; or a mechanical punch for punching dimples into, or apertures through, the sheet or wire. All the foregoing texturizing devices are well known in the various arts of manufacturing and are not shown. The sheet or wire can have the texturizing feature placed on only one side or on both sides. In addition, the texturizing feature can be continuous or it may be intermixed with unmodified regions.
Some illustrations of the texturizing features include a cross-hatch design as illustrated in FIG. 2, dimples as illustrated in FIG. 3, protrusions as illustrated in FIG. 4, linear grooves as illustrated in FIG. 5, curvilinear grooves as illustrated in FIG. 6, etchings from a laser as illustrated in FIG. 7, a layer of an abrasive coating as illustrated in FIG. 8, apertures from a mechanical punch or laser as illustrated in FIG. 9, crimping as illustrated in FIG. 10, or pitting from sand blasting as illustrated in FIGS. 19-22. In addition, the edges of the fasteners can have notches as illustrated in FIG. 11, which result from forming the dimples or apertures along a line where the individual fasteners will subsequently be separated. Some of the modifications are only effective to prevent slippage in one direction, such as the linear grooved surface of FIG. 5. The grooves of FIG. 5 are shown longitudinal along the fastener in order to prevent slippage of the fastener along the longitudinal of a blood vessel or the like, but could as easily be transverse along the fastener if another result was desired.
After the texturizing feature has been added, the sheet or wire is pulled into a cutting device, typically comprising a die having a plurality of longitudinal and transverse knives if sheets are used. As the die is actuated into contact with the sheet, the longitudinal knives cut the sheet into a plurality of bands, usually between 0.20 to 0.35 inches, which is to become the length of the fasteners. Simultaneously, the transverse knives cut into, but not quite through, the sheet to form a plurality of fasteners, each fastener having a width usually between 0.015 to 0.030 inches. The individual fasteners are not separated from the band at this point but are not securely attached to each other and could be easily separated by hand. In the case of wire, the wire is cut into a plurality of members having a length usually between 0.20 to 0.35 inches, which is to become the length of the fasteners. The wire members are subsequently juxtaposed to form bands for further processing. If the embodiment of the fasteners is linear shaped as shown in FIG. 14, then the fasteners are packaged with a predetermined number of fasteners per package and distributed. However, if the fasteners are to be formed into the other embodiments shown in FIGS. 1, and 15-22, then the bands of fasteners are processed further.
After leaving the cutting device, the bands of fasteners are pulled into a press where an upper plate having a plurality of linear ridges presses the bands into a reciprocal lower plate having a plurality of linear grooves corresponding to the ridges in the upper plate. The number of ridges or grooves equals the number of bands so that each band is pressed into only one groove. The shape of the groove complements the shape of the ridge so that when a band of fasteners is pressed between the ridge and groove, the band of fasteners will take on the form of the ridge or groove, which corresponds to the embodiments shown in FIGS. 1, and 15-18. The fasteners are then packaged with a predetermined number of fasteners per package and distributed.
To make the embodiments illustrated in FIGS. 19-22, the fasteners are formed such that the bands are substantially wider (i.e., the length of the fastener) than the fasteners described hereinabove. After formation as described above, the distal ends of the elongated arms are folded back to form the inner wall 11 of the fastener. The distal ends are preferably folded in such a manner that the fastener ends 12 are in contact with each other. The outer wall 13 is preferably U-shaped, such that the outer portions 14 of the arms are parallel to each other, although this is not critical. The inner wall 11 of this embodiment can have various shapes, depending on the personal preference of the user as well as the procedures for which the fasteners are to be used. A fastener having an inner V-shaped wall is shown in FIG. 19; a fastener having an inner U-shaped wall is shown in FIG. 20; a fastener having an inner oval-shaped, or modified C-shaped, wall is shown in FIG. 21; and a fastener having an alternate inner V-shaped wall is shown in FIG. 22. It is to be understood that the fasteners of this embodiment are to be used in the surgical devices already existing. Accordingly, it may be seen that the addition of a secondary wall will diminish the space within the crimping or clamping device such that an additional mass of metal is compressed. By compressing the greater mass within the same volume a more certain seal is achieved. Note that the fastener walls are not merely thickened but formed in discrete segments to enhance the engagement about the vessel by selection of the particular inner configuration as shown.
The fasteners of the present invention can be used in surgical staplers utilizing anvils or in surgical applicators utilizing a vise. Application of surgical fasteners has been well documented in the prior art and will not be repeated here. A good example of the application of fasteners with an anvil type surgical stapler was discussed by Noiles et al. in U.S. Pat. No. 4,407,286. The present discussion will focus on the fastener during and after application into the tissue. As the fastener is secured to close incisions or wounds, or to clamp vessels or ducts to prevent fluid flow, the novel features of the present invention become apparent. As the fastener closes around tissue, the tissue forms about the texturizing features. Since the interface between the fastener and the tissue is not smooth, but rather rough and abrasive, the fastener will resist displacement arising from hydrostatic pressure, movement of adjacent tissues, or other occurrences which would tend to displace the fastener. A fastener embodying features of my invention is shown secured to a blood vessel in FIG. 12 and maintaining closure of an incision in FIG. 13. Furthermore, the embodiment comprising the double wall feature illustrated in FIGS. 19-22 has the added benefit of an outer wall 13 to promote uniform compression of the inner wall 11 during application of the fastener. During application of presently used fasteners, the resistance from tissue can deform the fasteners, such that there is not uniform closure. This can subsequently lead to displacement of the fastener and fluid loss or hemorrhage. The outer wall 13 of the present invention acts to bolster the inner wall 11 during application of the fastener so that the inner wall will compress properly over the tissue, and subsequently adds fortification to the inner wall to prevent deformation from increasing hydrostatic pressure in the tissue.
It is to be understood that the form of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims. | An improved surgical fastener of the type used in a surgical applicator which has been modified to enhance the gripping capability of the fastener once secured. The fastener can have apertures therethrough or the surface can be knurled, crimped, etched with a laser, layered with an abrasive coating, sand blasted, punched, notched, or modified in any other manner which enhances the grip of the fastener when secured. Additionally, the fastener can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. An alternate embodiment includes a double wall to reinforce the fastener when secured. | 0 |
FIELD OF THE INVENTION
The present invention relates to a method for verifying that there exists adequate synchronisation of signals that cross clock environments.
BACKGROUND OF THE INVENTION
Many integrated circuits or “chips” go into production and exhibit intermittent failure. If digital circuits are designed to use entirely synchronous logic, with only one clock, synchronisation issues are generally trivial. However, in the world of digital circuit design, designers are more often required to create multi-clock designs. Multi-clock implies that the design has at least two clocks, but possibly many more clocks, that are asynchronous. These digital designs will include at least one, though probably multiple signals that cross the boundaries between clock environments. If these signals are not adequately synchronised then the circuit will develop errors.
There are tools currently available that are designed to verify that timing constraints are met in a digital circuit when it is being designed and verified. These tools may be applied where there is a block of synchronous logic. However, they are impractical when there are multiple asynchronous clocks within a circuit as there are an infinite number of possible clock timings that must be evaluated.
If data is transferred from one clocked environment to another, then there may be signals that return to the original environment, perhaps in a handshake arrangement. These signals verify that data has been correctly received. All of these signals will also need to be adequately synchronised. It is possible that some signals that cross clock boundaries do not need synchronisation if they are controlled by another signal that has been synchronised.
Once a circuit has been designed it is important that it is tested to ensure that there is adequate synchronisation to avoid the propagation of metastable states through the circuit. Typically, the circuits are very large and so computer simulation methods are used to verify the design of the circuit. There are two techniques which are used for analysing circuits—firstly, dynamic timing analysis using fully timed simulation, and secondly, static timing analysis. However, neither technique is appropriate for determining if there is adequate synchronisation. Formal methods and/or property checking methods again, at present, do not provide useful information. This is because the amount of computer resource required would be much more than would be reasonable to use. In other words, these methods suffer from the problems that they are not practical, not commercially viable and/or do not provide the required results.
SUMMARY OF THE INVENTION
It is an aim of embodiments to address one or more of the problems discussed.
According to one aspect of the present invention a method of testing a circuit under design is provided having a plurality of functional elements and having a plurality of clock environments, at least one signal passing from one clock environment to another in said circuit, said method comprising the steps of modelling at least one of the functional elements to have an unknown state as an output for a predetermined time after a timing event of a clock signal, simulating said circuit and determining which of said functional elements is a synchroniser to thereby identify if there is a synchronisation problem between for said at least one signal passing from one clock environment to another.
Embodiments of the present invention are arranged to address the problem of determining if a circuit has adequate synchronisation.
Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; and the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.
BRIEF DESCRIPTION OF DRAWINGS
For a better understanding of the present invention and as to how the same may be carried into effect, reference will now be made by way of example to the accompanying drawings, in which like reference numerals represent like parts, and in which:
FIG 1 a shows a circuit having two clock environments;
FIG 1 b shows a timing diagram for the circuit of FIG 1 a ;
FIG. 2 a shows a circuit in which a synchronisation stage is provided;
FIG. 2 b shows a timing diagram for the circuit of FIG. 2 a ;
FIG. 3 illustrates by a flow diagram of a method embodying the present invention.
FIG. 4 a shows an example digital circuit to illustrate an embodiment of the invention;
FIG. 4 b illustrates a timing diagram showing a first modification to flip-flop characteristics, for use in locating synchronisers;
FIG. 5 a illustrates the circuit of FIG. 4 a in which first and second synchronisers have been identified; and
FIG. 5 b illustrates a timing diagram showing modifications to first and second synchronisers of FIG. 5 a.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 a – 5 b discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged image processing system.
Reference is made firstly to FIG 1 a , which shows an example of a circuit where inadequate synchronisation may cause errors. In the example, the signal Q 1 crosses a boundary between two clock environments A and B. Two clocks (Clock 1 and Clock 2 ) are used to control basic synchronous memory storage devices, in this case D flip-flops FF 1 and FF 2 . Clock 2 is asynchronous to Clock 1 , that is to say that it has a clock source that is independent from the clock source that is used to derive Clock 1 . Although there may be a nominal relationship between the characteristics of the two clocks and their respective periods, and also some nominal phase relationship between the two clocks, these relationships are subject to varying physical effects. In this example the nominal period of Clock 2 is greater than Clock 1 , and therefore there will be a varying and indeterminate time difference between the rising clock edges of Clock 1 and the rising clock edges of Clock 2 . In another example, however, Clock 1 and Clock 2 might have the same nominal period but be out of phase with each other, or have an indeterminate and varying phase relationship.
Reference is now made to FIG. 1 b which shows the timing signals for the circuit of FIG. 1 in the case where a synchronisation error may occur. If there is a change, for example from 1 to 0 or from 0 to 1, in the input to the first flip-flop FF 1 , then the output of the first flip-flop FF 1 , labelled Q 1 , will change shortly after the rising clock edge of the first clock, Clock 1 . The time taken for this change to be fully effected is known as the output delay time, which, when FF 1 is operating within its specified limits, will have a value between a maximum time Tod (max) and a minimum time Tod (min) after the rising clock edge. Although the transition is a clean transition, from 0 to 1 or from 1 to 0, the precise timing of this transition cannot be determined and for this period, the signal Q 1 may be described as undefined and given the label ‘X’.
If the signal Q 1 is undefined at anytime after the specified setup time, T s , before the rising clock edge of Clock 2 and after the specified hold time, T h , after the rising edge of Clock 2 , as shown at 20 , then the second flip-flop FF 2 operates outside its specified limits and one such abnormal behaviour is described as the metastable state. The result of FF 2 entering the metastable state is that its output Q 2 may change either from 0 to 1, or from 1 to 0, at any time between T od (min) and any time thereafter with a probability decreasing to zero as the time of the transition extends to infinity. Although the transition is a clean transition, from 0 to 1, or 1 to 0, the precise timing of this transition cannot be determined and for this period of indeterminable value, the signal Q 2 may be described as undefined and given the label ‘X’. Any subsequent logic using the signal Q 2 will receive an undefined value, which may transition cleanly but at an indeterminate time, and further subsequent flip-flops may therefore also become metastable. Once one component of a digital circuit enters metastability, the consequence may be circuit failure in some or all of the digital circuit. The problem is that it is unclear what states various logic elements will be in and at that point the behaviour of the circuit will be unpredictable which is clearly undesirable.
A manufacturer of integrated circuits which include digital components such as D flip-flops might provide a setup time (T s ) and a hold time (T h ) associated with each component. In order to avoid metastability in this example, the input signal Q 2 must not change during the time interval bounded by T s before the rising clock edge of clock 2 , and a time T h after said rising clock edge.
Reference is now made to FIG. 2 a , which shows an example of a commonly accepted solution to the problem of metastability. In the example, two flip-flops SYNC FF 1 and SYNC FF 2 are positioned in series to create a ‘synchronisation stage’ C between the two clock environments A and B which are as described in relation to FIG 1 a and will not be described again in detail. The synchronisation stage receives the output Q 1 of the first flip-flop FF 1 as an input to the first synchronisation flip-flop SYNC FF 1 which receives the second clock signal, clock 2 , as its clock signal. The output Q 3 of the first synchronisation flip-flop Q 3 is input to the second synchronisation flip-flop SYNC FF 2 which also receives the second clock signal, Clock 2 as its clock input. The output Q 4 of the second synchronisation flip-flop SYNC FF 2 is input to the second flip-flop FF 2 of the second clock environment.
Generally the signal Q 4 will always be stable and may be used as a synchronised signal in clock environment B.
FIG. 2 b shows a timing diagram for the circuit of FIG. 2 a , and illustrates an example of the synchronisation error correction. As in the previous example, the worst case is chosen when second clock signal, Clock 2 , rises whilst the output Q 1 of the first flip-flop FF 1 is unstable. The result is that the output Q 3 of the first synchronisation flip-flop FF 1 is undefined (that is the timing of the clean transition from 1 to 0 is indeterminable) and, with decreasing probability for longer periods of Clock 2 , may not transition at all until after a subsequent rising edge of Clock 2 . If output Q 3 of the first synchronisation flip-flop SYNC FF 2 is now fed into the second synchronisation flip-flop SYNC FF 2 , and the positive clock edge of the second clock signal, Clock 2 comes at a time when the output Q 3 of the first synchronisation flip-flop SYNC FF 1 does not transition inside the limits of T s and T h , then the output of the second synchronisation flip-flop SYNC FF 2 , Q 4 , will change within its specified limits of T od (min) and T od (max). This output may then be used in the second clock environment B without problems of metastability.
It will be appreciated that the second synchronisation flip flop SYNC F 2 could in turn become metastable. However, the probability of this is considerably reduced. In practical circuits, the number of synchronisation flip-flops is adjusted according to the clock frequency of Clock 2 and according to other factors such as the risks and impact of circuit failure. It could be necessary to have three or more synchronisation flip-flops across a clock boundary for adequate synchronisation.
It should also be appreciated that although the output of the second synchronisation flip flop SYNC FF 2 , Q 4 , may be considered safe, that is changes within the specified limits of T od (min) and T od (max) with an acceptable probability, the precise clock edge following which a transition of the output, Q 4 , occurs is indeterminate. This indeterminism can easily be handled in a digital circuit by arranging some form of feedback or handshake back to the originating clock environment, A. Again, any such feedback will also require synchronisation.
Embodiments of the invention may be arranged to verify RTL register transfer level representation of a circuit and in particular to check that the circuit has sufficient synchronisation to avoid a metastable or unknown state from propagating through a circuit. The RTL representation of a circuit is synthesised to produce a gate level representation of the circuit. It should be appreciated that other embodiments of the invention can use other representations of a circuit which may or may not be at a gate level. In embodiments of the invention, the representation of the circuit may be mapped to a cell library which contains models of known entities.
Referring now to FIG. 3 , steps 1 a to if describe the first phase of an embodiment of the present invention; steps 2 a to 2 d describe the second phase of an embodiment of the present invention.
During the first phase synchroniser flip-flops within the design are located. The first step is to modify the modelling of all of the flip-flops within the design such that they output an “X” shortly after each positive clock edge. In this embodiment of the invention, the flip-flops are arranged to change state in response to a positive clock edge. However in alternative embodiments, the element in question which may or may not be a flip-flop may be responsive to a falling clock edge or even to both the rising and falling edges. The clock edge or edge to which the element is responsive is referred to as the significant clock edge.
In the embodiment described now, the significant clock edge is the rising or positive clock edge. The outputs of the flip-flops are modelled to have an “X” state (that is an unknown state which could be high or low) in response to each significant clock edge. The “X” state is arranged to last for a predetermined time after the significant clock edge. This predetermined time is a matter of design choice but is usually half a clock period or round about that value. Thus at a delay time T od after the rising edge of the clock signal, the flip-flop's output value is changed to ‘X’ for half a clock period after the rising clock edge.
The next step 1 b is to run the simulation with all the clocks in-phase and at the same frequency. This is important to ensure that the simulation environment is valid. If the simulation does not pass when all the clocks are in-phase, then it can be determined that there is a problem with the circuit design or simulation environment, in which case the next step is to return to step 1 a after making the necessary corrections. It is assumed that the simulation environment includes some mechanism that can be used to determine correct functionality and indicate a pass.
The next step is step 1 c where the simulation is run again. This time the clock frequencies are the same but the clocks are out of phase. In this case, it is not expected that the simulation would pass. A pass at this stage would indicate a problem with the simulation environment, in which case start again at 1 a after making the necessary corrections. Examine the simulation output and determine the extent of “X” propagation.
The next step is step 1 d of phase one. In this step, the model delay values are tuned such that the “X” values propagate but not excessively. It should be observed that “X” values propagate across the clock boundaries and thence to the connected logic. If “X” values cannot be traced to a signal crossing a clock boundary, then adjust the clock phase delay or reduce the duration of the “X” for the predetermined time after the significant clock edge and repeat from step 1 c.
The next step of phase one is step 1 e . In this step, use is made of the warnings which are generated when the simulation is run again with the tuned delay values. A warning is generated by the tool running the simulation if a potential timing problem is detected. Each of these warnings needs to be examined to see if the cause of the warning is a synchronising element. This process can be simplified if a list of those elements which provide a synchronising function are available. The designer of the circuit may for example be arranged to provide such a list.
In order to ensure that all synchronisers in each direction across the clock boundary can be traced, in the final step 1 f of phase one, steps 1 c through to 1 e are repeated using the opposite polarity of phase delay. That is to say, if Clock 2 was previously out of phase with Clock 1 by a time difference of ‘t’ nanoseconds after Clock 1 , the steps should now be repeated with Clock 2 out of phase with Clock 1 by a time difference of ‘t’ nanoseconds before Clock 1 .
The second phase of the method will now be described. In step 2 a , first and second synchronisers (for example as shown in FIG. 2 a and referenced as SYNC FF 1 and SYNC FF 2 ) are replaced by new modified models. The first synchroniser will output an “X” when in the metastable state, that is for a predetermined time after the occurrence of the significant clock edge. This time is a matter of design choice, but should be in the region of one clock period. The first synchroniser will be in the metastable state if its input is undefined at any time during the time T s before and the time T h after the rising clock edge of Clock 2 , and if the input shortly before and shortly after the ‘X ’ value are different, that is to say there has been a change from 0 to 1, or from 1 to 0. When not in the metastable state, the first synchroniser will also still output “X” for a shorter period in the range of half a clock period after each rising clock edge.
The second synchroniser will ignore the “X” received from the first synchroniser. In other words the “X” generated by the first synchroniser is not propagated by the second synchroniser. The second synchroniser will also continue to output an “X” value for a period after each rising clock edge.
In the second step 2 b of the second phase, the simulation is run twice, once for each polarity of phase difference. For this simulation, the clocks continue to have the same frequency and are out of phase, and test input signals are generated, such that logic transitions propagate through the circuit devices. As described above with relation to step 1 f , each polarity of phase difference is simulated such that if during the first simulation Clock 2 is out of phase with Clock 1 by a time difference of ‘t’ nanoseconds after Clock 1 , simulation should also be performed with Clock 2 out of phase with Clock 1 by a time difference of ‘t’ nanoseconds before Clock 1 . Warnings which are generated by the tool running the simulation are used to identify sources of “X” propagation.
In the third step 2 c of the second phase, each of the sources of the “X” propagation is examined to determine whether or not it is a genuine synchroniser which has previously been missed or a hazard.
In the fourth step 2 d , it is determined if there were any warnings in the last simulations from steps 2 b and 2 c which are due to a missed synchroniser. If so, then the second phase is repeated. If not, the process is finished.
It should be appreciated that if hazards are identified, the hazards can be examined further and if necessary, the design modified. A hazard is defined as an entity which propagates a metastable or unknown state “X” through a circuit.
To illustrate the method embodying the present invention, one example of a circuit under test will be discussed. Thus, what follows is a demonstration of an implementation of the present invention with one example of a circuit. It should be understood that this is only an example of a very simplified circuit and that the method described may be applied to a multitude of digital circuit types and designs.
Referring to FIG. 4 a , a circuit is shown which comprises five D-type flip-flops FF 1 , FF 2 , FF 3 , FF 4 AND FF 5 arranged in series. In this case the clock environment boundaries are taken as unknown and the synchronisation flip-flops are not distinguished from other flip-flops. There are two clocks, Clock 1 and Clock 2 which are at different frequencies. It will now be demonstrated how the synchronisation flip-flops may be located.
Firstly it must be understood that methods embodying the present invention are useful in verifying adequate synchronisation in a circuit when analysed at gate level. The circuit may have been designed in HDL (Hardware description language) or any other design language which is expected to be synthesised such that the circuit is given a representation at gate level, and may then be simulated at gate level using an appropriate simulation tool. Examples of HDL are Verilog and VHDL. A simulation should be performed as a first step with clocks in-phase in order to confirm that there is a valid simulation environment.
FIG. 4 b shows the timing diagram for the circuit of FIG. 4 a ; all of the flip-flops characteristics have been modified. The signal Q 1 illustrates the modification. All of the flip-flops have their output set to ‘X ’ a time T od after their output changes. The output should remain at ‘X ’ for a specified time T xd . This is shown by the ‘X’ blocks of signal Q 1 shortly after each of the rising clock edges of Clock 1 .
The simulation should now be run, with the flip-flops modified. An example of the simulation results is shown in FIG. 4 b . The second flip-flop FF 2 has the output Q 2 . There are no complications with this signal, there will be no errors reported by the simulator, and so it may be assumed that it is clocked by the same clock as FF 1 , and is not a synchroniser. Observing the output Q 3 however, there would be errors reported by the simulator as the signal will be read as an ‘X’. FF 3 is now metastable, and the simulation cannot continue. The signals Q 4 and Q 5 will now have “X” values throughout the clock period and this should result in functional failure of the circuit.
An aspect of the first step of this invention is that the flip-flops are modified to output the value ‘X’ shortly after each change. The length of time, labelled T xd in FIG. 4 b , that the signal remains at ‘X’ must be tuned to achieve the best results. A typical value would be one-eighth of the clock period. The optimum is if the ‘X’ will propagate without causing errors within the same clock environment.
This method described in the last two paragraphs will identify possible synchronisers when the design is simulated. Human judgement may then be used to determine if the flip-flop in question is really a synchroniser. In another implementation of this invention the process could also be automated to decide automatically whether an identified flip-flop is a synchroniser. At this stage it is not necessary that all synchronisers have been identified as further synchronisers may be identified in the following stages. However, it is important that any identified synchronisers are indeed synchronisers; else possible errors may be unnoticed during the following stages.
The first step of this embodiment of the invention may be aided by requesting a list of known synchronisers from the circuit designer.
The next step of the present invention is to alter the characteristics of the first and second known synchronisation flip-flops. First synchronisers are altered so that they output an ‘X’ when metastable. Second synchronisers are altered so that they ignore the ‘X’ output by the first synchroniser.
FIG. 5 a shows the circuit of FIG. 4 a with FF 3 and FF 4 now shown as the known synchronisers. These flip-flops are modified such that FF 3 , which is the first synchroniser, outputs an ‘X’ for one clock period if it clocks an ‘X’, and the value after ‘X’ is different from the value before ‘X’. A typical time value, labelled T xm in FIG. 5 b , for the ‘X’ output of the first synchroniser when metastable would be one clock period, although this is a matter of design choice. FF 4 , which is the second synchroniser, ignores the ‘X’ output from the first synchroniser.
The results of simulation of the circuit after these modifications can be seen in FIG. 5 b . For this simulation Clocks 1 and 2 have the same frequency, but are out of phase. Input D 1 is fed a test input signal, which in this example has a value of 1 during two rising clock edges of Clock 1 , and then a value of 0. This test signal is a matter of design choice, but should allow logic transitions to propagate through the circuit devices during the simulation. Q 3 is the output of FF 3 , the first known synchroniser. On the first shown positive clock edge of Clock 2 the input to FF 3 is an ‘X’, but the value after the ‘X’ is the same as the value before the ‘X’, which causes Q 3 to become ‘X’ only for the predetermined delay after the clock edge. On the second shown positive edge of Clock 2 the input to FF 3 is an ‘X’, but the value after ‘X’ is different from the value before the ‘X’, which causes Q 3 to become ‘X’ for the remainder of the clock cycle. For subsequent positive clock edges of Clock 2 , the input to FF 3 will always be ‘X’, but only after changes does the output Q 3 remain an ‘X’ for the whole of a clock period.
Q 4 is the output of second synchroniser FF 4 , which has been modified to ignore the ‘X’ output from the first synchroniser FF 3 . FF 4 ignores the ‘X’ signal generated by FF 3 , but continues to output an ‘X’ shortly after each significant clock edge of Clock 2 . These known synchronisers will not cause ‘X’ propagation, and therefore they will not cause hazard warnings during simulation.
It should be appreciated that the circuit shown in FIG. 4 a and 5 a is by way of example only and embodiments of the invention can be applied to other circuit arrangements. In practice there may be a plurality of first flip-flops FF 1 and combinatorial logic in the path from each first flip-flop output and the second flip-flop input. In other words, the arrangement shown in FIG. 4 a is generally much simpler than that which would be used in practice.
It should be understood that this is just an example, and that this invention is by no means limited to circuits containing this type of memory storage device, but may be applied to circuits with a multitude of gate or memory types.
In embodiments of the invention, the clock environments may have similar or quite different frequencies. By way of example only, one clock environment may have a frequency of the order of 100s of MHz whilst another clock environment may have a frequency of the order of 10s of MHz.
Embodiments of the invention may be used where there are two or more clock environments. In the case of more than two clock environments, in step 1 c of FIG. 3 , the clocks should all have the say frequency and be out of phase by varying amounts from a first clock, and then in steps 1 f and 2 d , when the opposite polarity of phase difference is tested each clock should have the same frequency but opposite polarity of phase delay in relation to the first clock.
From the foregoing it will be appreciated that, although specific exemplary embodiments of the invention have been described herein for purposes of illustration, various changes and modifications may be made or suggested to one skilled in the art without deviating from the scope of the invention. Accordingly, the invention is not limited except as by the appended claims. It is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims. | The present invention is directed to methods for verifying adequate synchronization of signals that cross clock environments. According to one exemplary method, a circuit under design includes a plurality of functional elements and a plurality of clock environments, and has one or more signals passing from one clock environment to another therein. The method includes the steps of (i) modelling at least one of the functional elements to have an unknown state as an output for a predetermined time after a timing event of a clock signal, (ii) simulating the circuit, and (iii) determining which functional element is a synchronizer to thereby identify if there is a synchronization problem for a signal passing from one clock environment to another. | 6 |
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of official duties by an employee of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon.
This application is a divisional of U.S. patent application Ser. No. 08/667,170 filed Jun. 20, 1996, now U.S. Pat. No. 5,854,440 which is a continuation-in-part of U.S. patent application Ser. No. 08/514,575, Filed Oct. 30, 1995 now U.S. Pat. No. 5,712,443.
FIELD OF THE INVENTION
The invention is related to the technical field of assault weapons and in particular to shoulder-launched rocket weapons.
BACKGROUND OF THE INVENTION
Shoulder-fired assault weapons are well known in the field. The earlier models stem from anti-armor weapons developed during World War II. Since that time, the weapon has evolved into a multi-purpose assault weapon suitable for a variety of targets. These targets include not only armored vehicles, but fixed structures and other types of vehicles. The challenge has been to provide a weapon with multiple capabilities suitable for both armored vehicles and lightweight structures such as light aircraft or helicopters. The weapon should also be effective against heavily reinforced bunkers and lighter weight structures. It has not been generally suitable to use a penetrating shaped charge against a lightweight structure as the round will completely pass through, typically exploding far beyond the structure. On tests with a helicopter, for example, a penetrating round punched small entry and exit holes and thereafter exploded 40 to 50 feet beyond the target, leaving the helicopter relatively undamaged. Similarly, a non-penetrating round is also unsuited for general purpose use. For example, a non-penetrating high explosive round has little effect on a hardened vehicle or structure.
Typical solutions to the problem of differing target hardness have resulted in a variety of types of warheads in a variety of calibers. The variety of warhead types greatly increases the number of weapons required to be carried and the logistics problems associated therewith and reduces the effectiveness of any particular fireteam in the field, since the fireteam can then only deal with limited types of targets. Additionally, spotting rounds must be matched to the ballistics of a particular warhead.
The current state-of-the-art weapon comprises a rocket launcher assembly with a spotting rifle attached to the right side of the launcher tube. There are numerous deficiencies with the current design. The right-side mounted spotting rifle is difficult to load and particularly difficult to re-load as the entire assembly is located away from the gunner on the opposite side of the rocket launcher. Further, the weapon lacks good balance resulting in unwieldy handling. The sighting of the spotting rifle is time consuming and not adaptable to changes in rounds under combat conditions. Further, the operation of the spotting rifle by cocking the bolt, reloading, clearing jams and other routine operations, typically requires an assistant gunner. Finally, the weapon is heavier because of a duplication of firing mechanisms, trigger linkages, hammers, etc., and the weapon has no "clean" side so that it can be placed on the ground (the current weapon having a scope on the left side and the spotting rifle on the right side).
What is needed is a lighter weight weapon adaptable to different rounds which can be handled by a single gunner, that is, operated from only one side of the weapon, such as the left side. Additionally, dual-function mechanisms to operate both the spotting rifle and the rocket launcher are needed to reduce weight and improve reliability.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a shoulder-launched multi-purpose assault weapon having interchangeable rocket tubes.
It is another object of the invention to provide a shoulder-launched multi-purpose assault weapon having an adjustable spotting rifle barrel for boresighting with the rocket tube.
It is yet another object of the invention to provide a shoulder-launched multi-purpose assault weapon having dual-function assemblies for various functions including safing, firing, assembly and disassembly, bolt locking back, cartridge ejecting, and breech locking.
It is a further object of the invention to provide a shoulder-launched multi-purpose assault weapon having a single sight adjusting mechanism which simultaneously adjusts both optical and open sight systems.
It is a still further object of the invention to provide a shoulder-launched multi-purpose assault weapon having all gunner activated mechanisms including firing, reloading, clearing jams, sighting, disassembly, and safing located on a single side of the weapon, preferably the left side of the weapon, to be accessible to the gunner in a firing position.
Accordingly, the invention is a shoulder-launched multipurpose assault weapon using a spotting rifle as the base weapon and having a rocket launcher mounted on the top side of the rifle. The rifle is configured with a single dual-function trigger mechanism which fires both the spotting rifle and the rocket launcher. A single trigger is connected to a unique dual sear mechanism operating both a rotating hammer and a plunger hammer. A single assembly and safing pin secures the trigger assembly to the weapon. When the pin is out, the weapon is safe. During assembly, the pin must be inserted and the weapon fully assembled before arming can be accomplished. A bolt lockback and cartridge ejector also serves two purposes. During firing, the device ejects spent spotting cartridges. When all cartridges have been fired, the device is used to lock the bolt open preparatory to reloading.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing objects and other advantages of the present invention will be more fully understood from the following detailed description and reference to the appended drawings wherein:
FIG. 1 is a perspective view of a shoulder-launched multipurpose assault weapon;
FIG. 2 is a partial side view of the weapon;
FIG. 3 is a partial cross-sectional view, taken at III in FIG. 2, showing the spotting rifle barrel;
FIG. 4 is an enlarged partial cross-sectional view, taken at IV of FIG. 3, showing the spotting rifle barrel alignment components;
FIG. 5a is an isolated top view of the spotting rifle barrel;
FIG. 5b is a view, similar to FIG. 5a, showing the side of the spotting rifle barrel;
FIG. 6 is an isolated view of the side of the receiver and trigger assembly of the assault weapon;
FIG. 7 is an enlarged view, similar to FIG. 6, of the trigger assembly;
FIG. 8 shows a schematic view of the dual firing mechanism with the primary sear engaging the connector link;
FIG. 9 is a schematic view showing operation of the primary hammer with arrows depicting potential movement of the components;
FIG. 10 shows the primary hammer in the fully extended position with arrows depicting potential movement of the components;
FIG. 11 shows the connector link engaging the secondary sear assembly;
FIG. 12 shows the secondary sear tripped;
FIG. 13 shows the secondary hammer fully extended and preventing connector link engagement;
FIG. 14 is an isolated side view of the internal mechanism of the butt assembly;
FIG. 15 is an isolated perspective view of the main spring receiver;
FIG. 16 is a side view with a partial cutaway of the main spring assembly;
FIG. 17 is a perspective view of the forward and center clamp rings;
FIG. 18a is a rear view of the open sight and mount assembly;
FIG. 18b is a cross-section of the open sight and mount assembly;
FIG. 19 is a perspective partial view of the multiple-purpose assault weapon showing the combination bolt lock and cartridge ejector mechanism;
FIG. 20 is an enlarged view of the area of the combination bolt and cartridge ejector designated in dotted area XX in FIG. 19;
FIG. 21 is partial cross-sectional top view, as taken along lines XXI--XXI of FIG. 6, of the combination bolt lock and cartridge ejector in the forward position with the shell in the chamber;
FIG. 22 is a view similar to FIG. 21, of the combination bolt lock and cartridge ejector moving to a rearward position and extracting the cartridge;
FIG. 23 is a view similar to FIG. 22, of the combination bolt lock and cartridge ejector with the spent cartridge ejecting out and a new round entering the chamber;
FIG. 24 is a view similar to FIG. 23, of the combination bolt lock and cartridge ejector with the bolt locked open;
FIG. 25 is an isolated side view of the magazine well assembly;
FIG. 26 is an isolated side view of the combination pin;
FIG. 27 is an end view of the combination pin of FIG. 26;
FIG. 28 is a cross-sectional view as taken along lines XXVII--XXVII of FIG. 27 of the combination pin of FIG. 26;
FIG. 29 is an isolated perspective view of a trigger housing plate; and
FIG. 30 is a cross-sectional top view as taken along lines XXX--XXX of FIG. 6, showing the combination pin installed in a trigger assembly.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the overall shoulder-launched multi-purpose assault weapon, designated generally by the reference numeral 10, is shown with its major components. The weapon assembly uses spotting rifle 100 as the basic building block. Rocket launcher tube 400 is mounted atop spotting rifle 100. The sight assembly 500, comprising both an optical and open sight system, is mounted to rocket launcher tube 400. The detachable rocket launcher tube 400 is attached to spotting rifle 100 by three circular clamps, a muzzle ring bracket assembly 421, a center ring bracket assembly 423, and an aft ring bracket assembly 425. The spotting rifle itself comprises an adjustable spotting rifle barrel 131, a spring-actuated bolt assembly 135, a trigger assembly 200, and a grip bracket assembly and butt assembly 300. The grip assembly is formed by forward grip 265 and the rearward pistol grip 261 which are connected by a connecting bar 267 on the lower ends. As all components with the exception of the sight assembly 500, including the optical sight 520, are mounted on the spotting rifle, the launcher tube may be easily replaced for maintenance or for the purpose of adapting to a different diameter rocket round.
Referring now to FIG. 2, the side view of the shoulder-launched multi-purpose assault weapon is shown generally at 110. Rocket launcher tube 400 serves as a part of the mount for adjustable spotting rifle barrel 131, spotting rifle receiver assembly 115 forming the other part. The details of the spotting round rifle barrel with adjusting mechanism (as shown in dotted area III), may be seen in FIG. 3.
Referring now to FIG. 3, an enlarged partial cross-sectional view taken at section III--III of FIG. 2, adjustable spotting rifle barrel 131 is shown as it is attached beneath rocket launcher tube 400. Adjustable spotting rifle barrel 131 has a retaining pin 132 to hold it attached to receiver block 130, which is attached to rocket launcher tube 400. The invention uses a convex spherical (or near spherical) surface on the rear of adjustable spotting rifle barrel 131 which is mated to a concave conical surface 137 on receiver block 130. Receiver block 130 is rigidly affixed to rocket launcher tube 400 by center ring bracket assembly 423 (as see in FIG. 1). At the muzzle end, supports for the adjustable spotting rifle barrel 131 are attached using muzzle ring bracket assembly 421. The radius of the convex spherical surface on the breech shoulders 141 of the rear of the adjustable spotting rifle barrel 131 is located at radius location 129. The radius center is located approximately a distance of one external barrel radius forward of the breech end of adjustable spotting rifle barrel 131. This radius location 129 allows a pivoting of adjusting spotting rifle barrel 131 in a small arc to maintain the rear interface of the barrel with receiver block 130. Adjustment of the angle of adjusting spotting rifle barrel 131 is accomplished by adjustment of the set screws shown more clearly in FIG. 4.
Referring now to FIG. 4, an enlarged partial cross-sectional view, taken at section IV-IV of FIG. 3, shows the adjustable spotting rifle barrel 131 alignment components. Immediately ahead of the muzzle shoulders 140 is a circular spring and washer assembly. This assembly includes a compression spring 142 which allows slight forward movement of the barrel. Immediately ahead of the compression spring 142 is a grip collar 143. Grip collar 143 is a split ring design allowing expansion of the collar depending on temperature of the barrel and also allowing a clamping effect as the grip collar is forced towards adjacent locating washer 144. Locating washer 144 is adjusted by three adjustment screws 145 (only one of which is shown here for clarity), each of the screws being located 120° around the barrel. The barrel locating bushing 149 is fixed around the muzzle end 139 of the adjustable spotting rifle barrel 131 and is itself encircled by bracket 421 which attaches to the main launcher tube (not shown in FIG. 4). A jam nut 147 secures the assembly to adjustable spotting rifle barrel 131. A barrel collar 148 acts as a support for locating washer 144 with respect to forward movement. Barrel collar 148 seats against locating washer 144 with a rounded surface. Locating washer 144 itself also has a spherical surface, as shown by surface 151, wherein the radius of forward side of the locating washer 144 is drawn from radius location 129, as shown in FIG. 3. As a result of both muzzle and breach radii being located around a common radius location 129, the barrel can be rotated slightly while maintaining snug contact with the fixed receiver breech surface.
The common radii centers of grip collar 143 and of the breech shoulders 141 (around radius location 129) allow the barrel to be adjusted up, down and laterally to make an exact parallel match to launcher tube barrel. As surfaces at the muzzle end and rear end of the barrel are radiused off the common center, there is no gap, extension, or spaces developed due to pivoting of the barrel. Additionally, the compression spring and conical surfaces shown on grip collar 143 and the matching conical surface on locating washer 144 allow an expansion of the barrel due to heat. As a result of these features, the spotting rifle barrel can be aligned to provide an exact parallel axis with the main longitudinal axis of the launcher tube and will remain in that position even after repeated firings and after heating of the barrel. As the barrel expands, compression spring 142 takes care of linear expansion of the barrel and the expansion of the split grip collar compensates for cross-sectional expansion of the barrel.
FIGS. 5a and 5b show top and side views of adjustable spotting rifle barrel 131. In the top view, a machined recess for retaining pin slot 138 is shown in the machined section 133 on the breech end of adjustable spotting rifle barrel 131. Muzzle shoulder 140 is located approximately two inches aft of the muzzle. Muzzle shoulder 140 has a radiused rear face and a flat forward face. The retaining pin 132 is also located in FIG. 1 at the top of the breech end of the adjustable spotting rifle barrel 131 for reference.
Referring now to FIG. 6, an isolated partially cutaway top view of the side of the trigger assembly and receiver mechanism comprises a single trigger 219 operating a dual firing mechanism. The dual firing mechanism comprises a double sear and double hammer device that is illustrated in more detail in FIG. 7. The cutaway position of FIG. 6 shows the means for attaching the forward and rear portions of the stock or pistol grip 261 to trigger assembly 200. An open access bore through stock 261 provides for installing attachment screw 262 which secures stock 261 to trigger frame 211. Frame cover 205 is attached to frame 211, and combination safing and assembly pin 221. A similar screw 263, also installed from the bottom through forward grip 265, completes the installation of the grips. A flat connecting bar 267 connects pistol grip 261 and forward grip 265 making a one-piece grip assembly. Flat connecting bar 267 serves as a rest for balancing the weapon on a support or on the ground, thereby eliminating the need for a bi-pod support as used in the prior art. Thumb selector lever 226 allows selection of either spotting rifle 100 or rocket launcher tube 400 using a single trigger. Trigger guard 218 protects trigger 219. The bolt assembly 159 can be seen in the closed position inside magazine well 181. The bolt operating handle 162 and main spring receiver tube 161 are shown for reference. Located on magazine well 181 is combination bolt lockback and cartridge ejector mechanism 171. Each subassembly is further described in subsequent drawings.
Referring now to FIG. 7, operation of one of the main features of this invention may be seen in trigger assembly 200. A dual firing mechanism comprises a trigger 219 having a trigger guard 218, a connector link 217, primary and secondary sear props 253, 252, primary and secondary sears 251, 254 and primary and secondary hammers 213, 227. Dual firing mechanism is mounted inside frame 211. A thumb selector lever 226 allows the operator to select either spotting rifle or rocket firing. Primary hammer 213 is a rotating hammer which rotates into a hammer slot 164 in bolt assembly 159, thereby striking weighted cylindrical firing pin 214. Firing pin 214 has a pointed center for firing spotting rifle cartridge 201. Secondary sear 254, also operated by trigger 219, releases a plunger-style secondary hammer 227 (shown cut off in this view). Selection of the hammer to be released is made by rotating thumb selector lever 226 (shown in FIG. 6) which lever 226 is attached to cam 231. Rotating cam 231 causes trigger connector link 217 to pivot, thereby engaging either primary sear prop 253 or secondary sear prop 252. Secondary sear prop 252, secondary sear 254, and secondary hammer 227 are all housed outside trigger frame 211 over pistol grip or stock 261 of the spotting rifle. A key element of this invention is pivoting connector link 217. Connector link 217 is pivotally connected to trigger 219. Primary sear 251 prevents primary hammer 213 from rotating in a counter-clockwise direction by catching the hammer on lug 233. As trigger 219 is pulled, connector link 217 slides into contact with the lug on primary sear 251. After contact between connector link 217 and primary sear 251 is made at lug 233, further application of pressure to trigger 219 will cause L sear 251 to move counterclockwise out of contact with primary hammer 213 allowing operation of the hammer.
Operation of the trigger and dual firing mechanism may be more fully understood by reference to FIGS. 8-13. Referring now to FIG. 8, an enlarged isolated view of the dual firing mechanism is shown as mounted inside frame 211. Rotating the eccentric cam 231 (by thumb-operated selector lever 226 shown in FIG. 6), adjusts connector link 217 for engagement of either primary sear 251 or secondary sear 254. Secondary sear prop 252, secondary sear 254, and secondary hammer 227 are all housed outside frame 211 over stock 261 (shown in FIG. 7). As trigger 219 is pulled, connector link 217 (pivotably connected to trigger 219 by horizontal pin 216) slides into contact with a lug 233 on primary sear 251. Connector link 217 is forced into contact with the lower surface of primary hammer 213 at point 249 by the action of connector link spring lever 248. Spring lever 248 is forced to rotate in a counterclockwise direction by is primary hammer spring 245. After contact between connector link 217 and primary sear 251 is made at lug 233 further application of pressure to trigger 219 will cause sear 251 to move counterclockwise out of contact with primary hammer 213, allowing operation of hammer 213. As depicted, primary hammer 213 is a rotating type hammer of conventional design.
Referring now to FIG. 9, a schematic view showing operation of the primary hammer with arrows depicting potential movement of the components can be seen. As trigger 219 is depressed, as depicted by arrow 220, sear 251 moves out of contact with primary hammer 213 which begins to rotate in a counterclockwise direction as shown by arrow 228.
Further operation of the primary hammer may be seen by referring to FIG. 10. In this figure, after the complete travel is of trigger 219, primary hammer 213 is in a fully extended position. The disconnecting action of pivoting connector link 217 is shown in this view where tip 242 of primary hammer 213 has caused pivoting connector link 217 to move in a downward direction as shown by arrow 244. In this positions connector link 217 is no longer in contact with primary sear 251. Sear 251 cannot rotate clockwise under the pressure of its spring (to re-engage the notch on the primary hammer) until the hammer is recocked. In order for the connector to come in contact with the sear, force must be removed from trigger 219. Releasing trigger 219 allows connector link 217 to move rearward and reengage the sear.
Referring now to FIG. 11, a schematic view, similar to FIG. 10, of the connector link engaging the secondary sear assembly is shown. Operation of secondary sear and secondary hammer can be seen where connector link 217 is rotated, as shown in a clockwise direction. Connector link 217 is forced to rotate in a counterclockwise direction as shown by arrow 239. This rotation causes an engagement with secondary sear prop 252 at lug position 241. A spring force, represented by arrow 270, is applied to secondary hammer 227. Secondary hammer 227 is a plunger or piston style hammer which operates by sliding right to left in this depiction.
Referring now to FIG. 12, a schematic view, similar to FIG. 11, of the secondary sear tripped is shown with trigger 219 fully depressed, secondary sear prop 252 is pulled by connector link 217 out of contact with secondary sear 254, thereby allowing secondary hammer 227 to force secondary sear 254 to rotate clockwise (depicted by rotation arrow 291) as it moves to the left.
Referring now to FIG. 13, a schematic view, similar to FIG. 12 of the secondary hammer 227 is shown at the extent of its movement. Hammer nose 315 lies in a position to prevent connector link 217 from rotating clockwise under force from connector link spring lever 248. In this position, connector link 217 cannot engage either sear mechanism. Further, firing of the spotting rifle after firing the main round is prevented by this sear location. The secondary sear prop 252 and secondary sear 254 are shown for reference.
FIG. 14, an isolated side view as taken along lines XIV--XIV of FIG. 2, shows the internal mechanism of butt assembly 300 (shown in FIG. 1). Butt-assembly 300 contains secondary hammer 227 extending to the rear of the assembly. A single pulse high voltage generator 301, contained within sealed butt casing 302, provides the electrical pulse to fire a rocket round. During operation, pulse generator 301 is actuated by plunger-style secondary hammer 227, which causes magneto bar 303 to snap across poles of magnets 305 and 307, thereby reversing the polarity and generating a pulse firing charge. Conventional circuitry 309 routes the charge through a pair of connectors 311 (only one shown in FIG. 14) to the rocket in the launcher tube. The entire unit is sealed in butt assembly 300 so that it is both waterproof and dirt and dust proof. The hammer nose 315 is shown for reference with the preceding drawing.
FIG. 15 is an isolated perspective view of main spring receiver tube 161 with bolt operating slot 163 identified. Mounting block 170 holds combination bolt lockback and cartridge ejector mechanism 171 (shown in FIG. 6 and more fully described in FIGS. 19-24) using a pin (not shown in FIG. 15) through bore 177. Mounting lug 165 mates with center ring bracket assembly 423 (shown in FIG. 1).
FIG. 16 is an isolated side view of main spring assembly 136. Main spring assembly 136 comprises a main spring 134 and an inner spring 154 (shown in partial cross-section). Concentric inner section 156 and concentric outer section 157 allow bolt assembly 159 (not shown in FIG. 16) to provide a dynamic response when the weapon is fired so that the spent cartridge is ejected and a new round is chambered.
Referring now to FIG. 17, a perspective view of the forward and center clamp rings, bracket 465 mates on center ring bracket assembly 423 with mounting lug 165 (shown in FIG. 15) to attach rocket launcher tube 400 (not shown in FIG. 17) to spotting rifle trigger and receiver group. Aft ring bracket assembly 425 is shown for reference. As shown by offset 706, the position of rocket launcher tube 400 is mounted off-center and to the right of the centerline 709 of the spotting rifle. This offset provides a proper lateral balance to the weapon and locates optical sight 520 (shown in FIG. 1) in a more nearly aligned position with the gunner's sight line.
The remaining major component of the weapon is combination optical and open sight assembly 500. The components of the sight assembly (with optical sight 520 removed for clarity) are shown in FIGS. 18a and b. FIG. 18a is a rearview, as seen by the operator, showing elevation adjustment knob 501 and rear peep sight 503. FIG. 18b is a cross-section, as taken along lines XVIIB--XVIIB of FIG. 18a, showing elevation pivot 505 and elevation knob 501 with its operating mechanism. Front sight 509 is a V-shaped sight as may be partially seen in FIG. 18a. Sight adjustments move both the optical tube (not shown in FIGS. 18a and 18b) and open sights formed by rear peep sight 503 and front sight 509. By this arrangement, both sets of sights (the open sights and the optical sights) are adjusted simultaneously, thereby allowing an immediate transition between the optical sight and the open sight as needed.
Referring now to FIG. 19, combination bolt lockback and cartridge ejector mechanism 171 mounted on the receiver of spotting rifle 100 which is attached to a rocket launcher tube 400. The entire weapon is referenced generally by numeral 10. Within dotted circle XX, bolt operating handle 162 is shown for reference.
The details of combination bolt lockback and cartridge ejector mechanism 171 may be seen in FIG. 20 which is an enlargement of dotted area XX of FIG. 19. The bolt (not visible in this view but attached to bolt handle 162) operates in left and right directions as depicted by arrow 160. Combination bolt lockback and cartridge ejector mechanism 171 moves in and out of mounting block 170 as depicted by arrow 174. When the bolt assembly is drawn back to a rearward position (to the right in the Figure), combination bolt lockback and cartridge ejector mechanism 171 can be depressed by the operator to slide in front of bolt assembly as depicted by arrow 174, thereby locking the assembly open. The entire mechanism is held in place by pin 178.
Referring now to FIG. 21, the operation of combination bolt lockback and cartridge ejector mechanism 171 may be seen in relation to operating bolt assembly 159. As depicted in this figure, bolt assembly 159 is in forward position with cartridge 201 in the firing position. Cartridge ejector 172 with bolt assembly 159 in the forward position, is pushed outward by the bolt (down in the Figure) away from the centerline of bolt assembly 159. Cartridge ejector 172 slides along a slot in bolt assembly 159. As bolt assembly 159 is retracted, a beveled section of the slot allows ejector 172 to slide inward toward the center of bolt assembly 159. Bolt lock 176 is shown having bolt-engaging end 173 and an elongated hole 179, the entire assembly held in place by pin 178. A single spring 175 insures that ejector 172 remains snug against the bottom of the slot. Spring 175 is contained within the tubular bolt lock 176 and cartridge ejector 172 slideably fitted into a slot in the bolt lock 176, thereby depressing spring 175. Both the bolt lock 176 and the cartridge ejector 172 have elongated holes for receiving pin 178. By this arrangement, a single spring 175 provides both the bolt lock disengaging force and the engaging force for the cartridge ejector.
This action is more clearly depicted in FIG. 22 wherein bolt assembly 159 is shown moving to the rearward position, as depicted by arrow 202, and ejector 172 is beginning to extend inward to engage spent cartridge 201. Single ejector and locking spring 175 urges ejector 172 toward the center of bolt assembly 159. The single ejector and locking spring 175 provides dual functions for combination bolt lockback and cartridge ejector mechanism 171, providing a releasing spring force against bolt lock 176 and an inward pressure on the ejector 172. The elongated hole 179 on bolt lock 176, a hollow cylindrical tube having a slot on the rearward edge, allows the bolt lock 176 to move in and out on pin 178. The bolt lock 176 has a slot for ejector 172 and beveled shoulders on the bolt-engaging end 173. Although not shown in this cross-sectional view, it also has an elliptical hole for pin 178 identical to the elliptical hole shown in ejector 172.
Referring now to FIG. 23, spent cartridge 201 is being ejected, and the combination bolt lockback and cartridge ejector mechanism 171 is shown with cartridge ejector 172 in the fully extended position. Further extension of ejector 172 is prevented by elongated hole 179 located at pin 178. As seen in FIG. 23, single spring bolt lock and cartridge ejector spring 175 is in its most extended position. Lock back 176 and bolt-engaging end 173 are shown in the fully unlocked position.
Referring now to FIG. 24, with bolt assembly 159 held in the full aft position, bolt-engaging end 173 of combination bolt lockback and cartridge ejector mechanism 171 may be engaged by depressing bolt lock 176 as shown by arrow 195. Moving bolt lock 176 inward compresses single spring bolt lock and cartridge ejector spring 175 and moves lock 176 to the full travel of elongated hole 179 at pin 178. A small portion of cartridge ejector 172 can be seen near the end of bolt 159.
Referring now to FIG. 25, magazine well 181 is shown with magazine locking mechanism 187. The magazine locking mechanism 187 rotates around pivot pin 185 when pressed downward, thereby lifting lock 183 and releasing an expanded magazine after firing. Bolt operating slot 163 is shown in main spring receiver tube 161 for reference purposes.
Referring now to FIG. 26, the combination pin, (designated generally by the reference numeral 221), attaches trigger frame cover 205 to trigger frame 211 (neither shown in this figure). Additionally, rotation of pin 221 safes and arms the weapon. Combination pin 221 comprises a handle 222 attached to a retainer pin and cam assembly 215, retainer pin 225 having a ball-locking mechanism 229. Safing cam 230 provides an eccentric movement during rotation in order to enable the trigger assembly. At the end of cam 230 nearest the handle, a detent-engagement mechanism 224 is affixed.
The shape of combination pin 221 components may be further understood by reference to FIG. 27. Handle 222 is fixed to cam 230 so that extended part of cam 230 covers a one-half circle on the lower right side of handle 222. With handle 222 in this position, safety detent engagement mechanism 224 is at the top location, 450 away from center line of handle 222 and located on the non-cam side of retainer pin 225.
Referring now to FIG. 28, a cross-sectional view of combination pin 221 shows the internal mechanism with ball locking mechanism. Handle 222 is attached to retainer pin and cam assembly 282 and is held in place by spring pin 281. Retaining pin and cam assembly 282 extends from inside handle 222 to insertion end 285 of pin 221. Retainer pin and cam assembly 282 is a single piece housing having a smaller center bore at insertion end 285 and a larger center bore opposite handle end. Slots 283 are cut into ball-locking rod 288 to allow movement of locking balls 289. A dual-action spring 286 presses the detent-engagement mechanism 224 (see FIG. 26) toward insertion end 285 of combination pin 221. Dual-action spring 286 also presses against washer 287 which is affixed to ball-locking rod 288. This action urges ball-locking rod 288 toward the handle end of combination pin 221. With ball-locking rod 288 in the position shown (outward toward the handle), locking balls 289 cannot retract and combination pin 221 is held in place to secure trigger frame cover 205 to trigger frame 211 (neither shown in this view). When ball-locking rod 288 is pressed inward from trigger frame 211, handle 222 and locking balls 289 are aligned with slots 283 in ball-locking rod 288, thereby releasing the pin. The entire combination pin 221 can then be removed from the trigger assembly.
FIG. 29 shows a trigger frame cover 205 which mates with combination pin 221 (shown in FIG. 28) to provide detents 206 for detent-engagement mechanism 224 (shown in FIG. 28). Aperture 207 is shaped to match the cam shape of combination pin 221, thereby allowing insertion of the combination pin only in the safe position. Due to the rotational position of the detent engagement mechanism 224 with respect to safing cam 230, when the combination safing and assembly pin 221 is aligned with the aperture 207 so that it can be inserted, the safing cam 230 is not supporting the forward position of connector link 217 (shown in prior views). After insertion, the combination safety and assembly pin 221 (shown in FIGS. 26 and 27) may be rotated to cause the safing cam 230 to raise the forward portion of the connector link 217 thereby arming the weapon.
Referring now to FIG. 30, combination pin 221 is shown inserted in trigger assembly 200 of weapon 10. Trigger assembly 200 is inserted into the weapon from the bottom and combination pin 221 is then inserted from the side, as shown. As the cam action of pin 221 is required to enable the weapon, the weapon is safe whenever pin 221 is removed. Additionally, due to the shape of aperture 207 (as seen in FIG. 29), combination pin 221 must be inserted in the safe position and fully seated before it can be rotated to the arm position. This feature means that the safety of emergency field disassembly of the weapon is greatly enhanced.
OPERATION OF THE INVENTION
The operation sequence of the weapon illustrates many of the features. The shoulder-laundered multiple-purpose assault weapon is laterally balanced and may rest on the shoulder with only a one-handed grip by the gunner. The gunner can insert a magazine of spotting ammunition without removing the weapon from the firing position, the entire weapon weighing on the order of 20 lbs. Thereafter, the gunner can fire spotting rounds in a semiautomatic mode while making final sight adjustments. When ready to launch the rocket, the thumb selector lever above the pistol grip is held down and the trigger is depressed. In this mode, the secondary hammer fires which causes the one pulse generator to produce a firing charge for rocket ignition. After firing, the weapon may be grounded by laying it on its right side, which is a "clean" side having no components mounted on that side. A single operator can fire and reload at the same pace as the conventional gunner and assistant teams. Should the gunner need weapon support during firing the built-in rest extending between the grips provides a lighter and already ready alternative to the folding bi-pod.
The benefits and novel features of the invention are numerous. A single trigger operates two separate hammer types necessary for firing either the spotting rifle or the main launcher tube. Selection between the weapons firing is accomplished by a simple depressible thumb selector lever. The mechanism allows repeated firing of the spotting rifle, but precludes further firing after the main munition is expended (until reloading the main munitions). The spotting round barrel axis can be quickly and easily aligned with the launcher tube and can achieve a high level of precision in the alignment. Neither a firing of the spotting rifle or the rocket tube, nor a changing in heat or temperature of any part alter the alignment. Any longitudinal expansion is compensated for by compression of the spring retainer in the conical gripping collar. The split conical gripping collar compensates for any cross-sectional expansion of the barrel. All of these movements or expansions can take place while maintaining a precise alignment. Additionally, the common radiused surfaces on either end of the barrel allow the barrel to be rotated through a small arc necessary to make the adjustments while maintaining a perfect mate with the receiver. The combination pin provides a dual function, both safing the trigger housing and securing it to the weapon. Additionally, the single operating spring performs a dual function, both engaging the position detent and operating the ball lock mechanism. Further, removal of the pin automatically safes the trigger housing, thereby preventing inadvertent firing during assembly or disassembly of the weapon. The dual functions serve to reduce the number and cost of parts, simplify the design, and improve reliability.
The combination bolt lockback and cartridge ejector mechanism provides a simple mechanical device which has a high degree of reliability under extreme adverse conditions of dirt, dust, mud and water contamination. The single operating spring performs both the functions of operating the lock and the ejector. The reduced part count increases reliability, decreases weight, and reduces the cost of the weapon. The breech bolt and locking mechanism has a reduced parts count, has fewer operating parts, has no engaging locking device and as a result is less expensive and more reliable. Further, the new bolt and lock assembly can operate with any type of cartridge. There is no requirement for the expensive dual cartridge design currently in use. The invention allows the gunner (of a weapon to which this invention is attached) to quickly switch from an iron sight with a large field of view to a high-powered optical sight with a confined field of view without loss of weapon aim. It also allows the gunner to switch instantly to the iron sight in the event of optical sight failure such as sight fogging. Further, the dual mounting structure of the adjustable sight mounting bracket provides a first and second mounting structure which allow both the iron sight and the optical sight to be bore-sighted at a particular range and thereafter to have a single adjustment point to adjust both the optical sight and the iron sight for either elevation or windage. Additionally, the adjustable sight mounting bracket allows the use of a less expensive non-adjustable optical scope as the adjustable bracket itself can provide alignment of the scope. Thereafter, the iron sights can be aligned using the iron sight adjustments. Further adjustment for both sights can then be made as described for target range or windage changes.
Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described. | A shoulder-launched multi-purpose assault weapon having a modified spotting rifle with a top-mounted rocket launcher tube is provided. The spotting rifle forms the base structure of the weapon and all weapon controls are located on the rifle. The rifle has several dual-function mechanisms which perform the combined functions of assembly and safing, bolt-locking back and cartridge ejecting, simultaneous adjustment of both open and optical sights, firing, selectively, of both the spotting round and the rocket round. The combination of these dual-firing mechanisms provides a lighter weight, better-balanced and smaller weapon. The reduction in parts count improves reliability and lowers cost. Other improved features include an adjustable spotting rifle barrel used to match the boresight of the rocket tube and an improved locking mechanism. A dual function trigger assembly operated two sears from a single trigger. The primary sear operates a rotating style hammer while the secondary sear operates a plunger-style hammer. The hammers fire, respectively, the spotting rifle and the rocket tube as selected by the gunner. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for preparing high-purity epichlorohydrin from epichlorohydrin containing technical impurities by distillation in a column which is equipped with an evaporation or heating device located at or near the sump of the column, the preparation of high-purity epichlorohydrin being improved by certain processing techniques and/or apparatus features or apparatus combinations.
German Auslegeschrift 1,210,777 discloses a process for the preparation of epichlorohydrin by dehydrochlorination of 1,2-dichloropropan-3-ol with alkaline agents in aqueous medium at elevated temperature. According to Example 1, paragraph 2, crude epichlorohydrin is rectified via a twenty-plate column, yielding a "pure" product with a boiling point of 115° to 116° C. in addition to unreacted dichloropropanol. However, even after rectification, the epichlorohydrin obtained in this manner still contains interfering impurities in the form, inter alia, of halogenated hydrocarbons and the like. Elimination of such impurities is important where the epichlorohydrin is to be used for making ultrapure resins for use in electronic components or devices, microchips and the like.
OBJECTS OF THE INVENTION
One object of the present invention is to provide a process for preparing epichlorohydrin of enhanced purity with respect to technical grade reagent.
Another object of the invention is to provide a process for preparing epichlorohydrin with a substantial reduction in the chlorinated hydrocarbon content with respect to technical grade epichlorohydrin.
SUMMARY OF THE INVENTION
These and other objects of the invention are achieved by providing a process for preparing high-purity epichlorohydrin from epichlorohydrin containing technical impurities, which comprises;
fractionally distilling technical epichlorohydrin in a column having at least 15 theoretical plates and which is provided with heating evaporating means located at or near the sump of the column, inlet means for introducing technical epichlorohydrin at an intermediate point in said column, and outlet means for withdrawing high-purity epichlorohydrin at a point above said inlet means;
wherein the technical epichlorohydrin is introduced into said column at a distance from said evaporation or heating means which is greater than one-tenth of the total length of the column, and the high-purity epichlorohydrin is withdrawn at a distance from said evaporation or heating means which is greater than one-third of the total length of the column.
DETAILED DESCRIPTION
The invention provides a process for the preparation of high-purity epichlorohydrin from epichlorohydrin containing technical impurities by distillation in a column equipped with an evaporation or heating device located at or near the sump of the column. The term "technical epichlorohydrin", as used herein, denotes epichlorohydrin having a purity of up to about 997 g/kg of epichlorohydrin, and normally having a chlorinated hydrocarbon content of at least 2 g/kg. Even higher purity reagent, e.g., up to about 999.1 g/kg, with respect to epichlorohydrin content, can still be considered technical grade, in the sense of being unsuitable for use in preparing resins for certain sensitive applications in electronic or microchip devices, if its content of chlorinated hydrocarbons is higher than about 0.7 g/kg.
According to the invention, technical grade epichlorohydrin is subjected to fractional distillation, preferably in a perforated-plate column, bubble-cap plate column and/or packed column. The column is equipped with an evaporation or heating device (or an evaporation or heating area or zone) located at or near the bottom of the column (or below the first plate), and is furnished with means to introduce an inlet stream at a point intermediate between the bottom and the top of the column, means to withdraw a product stream at a higher intermediate point on the column, means to withdraw a lower-boiling stream at or near the top of the column, and means to withdraw a higher-boiling stream at or near the bottom of the column.
Normally, the column will have at least 15 theoretical plates, preferably at least 20, and more preferably at least 25 plates.
The technical epichlorohydrin is fed into the column at an intermediate point along its length, at a distance from the evaporation or heating device (or the evaporation or heating area or zone) which is greater than one-tenth, preferably greater than one-quarter, of the total length of the column. High-purity epichlorohydrin is drawn off at a distance from the evaporation or heating device (or the evaporation or heating area or the evaporation zone) which is greater than one-third, preferably greater than one-half, of the total length of the column.
A lower-boiling stream (epichlorohydrin containing a higher percentage of impurities and/or low-boiling azeotropic mixtures) is continuously drawn off at the head of the column and a higher-boiling stream (epichlorohydrin containing a higher percentage of impurities and/or high-boiling azeotropic mixtures containing epichlorohydrin) is continuously drawn off at the foot of the column.
The process according to the invention is performed at a pressure in the column of 0.2 to 1.3 bar, preferably 0.5 to 1 bar or 1.05 bar. However, it is particularly advantageous to operate at normal pressure (smaller equipment costs) or under a vacuum of 0.8 to 0.98 bar (inter alia gentle evaporation of the epichlorohydrin).
The minimum distance for the inlet or inlet position(s) for the technical epichlorohydrin to be purified from the evaporation or heating device (the evaporation or heating area or the evaporation zone) depends, inter alia. on the total length of the column, the filling with certain packings and/or the minimum spacing of the perforated plates, and is, for example, in the case of very long columns or heavily or densely packed columns and the like, greater than one-tenth of the total length of the column. It is, however, particularly expedient for this minimum distance to be greater than one-eighth or one-sixth, preferably greater than one-quarter, of the total length of the column.
According to a preferred embodiment of the process according to the invention, the technical epichlorohydrin is pre-heated to a temperature below the boiling point prior to being fed in the column. This preheating, in conjunction with the above procedural measures, is of particular importance for achieving the required degree of purity of the high-purity epichlorohydrin.
In the process according to the invention, the difference in the preheating temperature and the operational temperature in the column is not greater than 50° C., preferably not greater than 10° C. The purpose of the preheating is to bring the temperature of the technical epichlorhydrin to be fed into the column to the same or approximately the same operational temperature prevailing in the column. The term "operational temperature" refers to the temperature in about the middle region of the column.
The process according to the invention is preferably performed as a continuous process, so that the pre-heated technical epichlorohydrin is continuously fed into the column at a distance from the evaporation or heating device which is greater than one-tenth, preferably greater than one-quarter, of the total length of the column. While the high-purity epichlorhydrin is drawn off at a sufficient distance above the inlet position to effect the desired enhanced purity, the impurities are continuously drawn off at the head and at the sump.
The pump output for feeding the technical epichlorohydrin into the column is regulated according to the invention in such a manner that the amount fed in is equal to or approximately equal to the sum of the amounts discharged or drawn off.
The evaporation and/or heating of the epichlorohydrin in the column is preferably carried out using a circulation evaporator. According to a preferred embodiment of the process according to the invention, a distance is maintained between the inlet position(s) of the technical epichlorohydrin in the column and the outlet position(s) for the high-purity epichlorohydrin which is greater than one-fifth of the length of the column, preferably greater than one-quarter of the length of the column. The high purity epichlorohydrin is then drawn off above the inlet position(s) of the technical epichlorohydrin
The process of the invention advantageously is carried out in an apparatus which comprises at least one column which is equipped with evaporation or heating means located at or near the sump of the column and at least one inlet and one or more outlet means or devices. According to the invention, the outlet position for the high-purity epichlorohydrin in the vertical distillation column is located above the inlet position of the technical epichlorohydrin. The heating or evaporation device for the column, preferably a perforated-plate column, a bubble-cap plate, and/or a packed column, is located below the inlet position(s) of the technical epichlorohydrin,
The distance of the inlet position(s) for the technical epichlorohydrin from the evaporation or heating device is greater than one-tenth, preferably greater than one-quarter, based on the total length of the column, while the distance of the outlet position(s) for high-purity epichlorohydrin from the inlet position(s) of the epichlorhydrin is greater than one-fifth, preferably greater than one-quarter, of the length of the column. According to a particularly expedient embodiment, a distance was maintained between the inlet position(s) for the technical epichlorohydrin and the evaporation or heating device which was greater than one-sixth, preferably greater than one-quarter, based on the total length of the column.
The evaporation or heating device of the column preferably consists of a circulation evaporator.
A device for preheating the technical epichlorohydrin to be fed in is attached to the column. The preheating device is preferably located on or in a feed vessel or a feed device or on or in a storage vessel or a similar container which serves as a receptacle for the technical epichlorohydrin to be fed in and which is provided, preferably in its inlet device, preferably inlet tube and the like, which is attached to the column, with metering and/or closure devices, valves and the like. Furthermore, according to one embodiment, pumps, injectors and the like are located on the feed vessel or on the inlet device.
The invention further relates to the use of the high-purity epichlorohydrin, preferably prepared by the process according to the invention, for the preparation of epoxy resins for electronic components, electronic devices and microchips.
The high-purity epichlorohydrin prepared according to the present process generally has a purity of at least about 999.2 g/kg of epichlorohydrin, preferably 99.4 g/kg, more preferably 999.5 g/kg, 999.7 g/kg and even up to 999.95 g/kg. It generally has a much reduced content, e.g., at least as low as 0.5 g/kg, preferably as low as 0.3 g/kg, of halogenated hydrocarbons, or is virtually free from halogenated hydrocarbons, i.e., about at the limit of detection of sensitive instruments, or about 50 ppm by weight. Such high-purity epichlorohydrin is reacted in a manner known per se with monofunctional or polyfunctional phenols, carboxylic acids or amines, preferably aromatic amines. The resultant epoxy resins are formed or processed to produce electronic components, devices or microchips without the use of processing auxiliary agents containing chlorine ions or halogen ions or using only small amounts of such agents. The advantage of using materials with a very low halogenated hydrocarbon content in such devices is minimization of corrosion, which can occur if chlorine or other halogens are liberated by local heating or electrical decomposition of the halogenated compounds.
For continuous operation in the preparation of high-purity epichlorohydrin on the laboratory scale, a piston metering pump is preferably used for feeding technical epichlorohydrin to the column. The metering output is controlled by a regulator, preferably a level regulator, placed in the sump phase. The discharge at the head is preferably provided with a regulator, preferably a magnetically or pneumatically controlled liquid divider. The sump and product discharge has at its disposal pumps known per se, for example piston or membrane metering pumps. Evaporation devices, preferably circulation evaporation devices known per se, for example quartz electric heating rods or metal insert heating devices and the like, controlled by probes in the sump and in the regulator, are used as sump heaters or circulation evaporators.
The following example illustrates the process of the invention and the use of apparatus according to the invention, but is not limitative thereof.
APPLICATION EXAMPLE
At the height of the 8th plate (counted from the foot of the column) of a perforated-plate column having a total of 35 plates, 2.2 liters of technical epichlorohydrin with an epichlorohydrin content of 999.1 g/kg, pre-heated to 114° C., are introduced under normal pressure. 300 ml of a mixture of epichlorohydrin and low-boiling components are drawn off per hour at the head of the column, and 350 ml of a mixture of epichlorohydrin and high-boiling components are drawn off per hour at the sump.
At the height of the 25th plate 1550 ml of high-purity epichlorohydrin with a epichlorohydrin content of 999.7 g/kg at 116° C. are drawn off per hour.
The chlorinated hydrocarbon content of the technical epichlorohydrin is 0.7 g/kg, and of the high-purity product is 0.2 g/kg. | The present invention relates to a process for preparing ultrapure epichlorohydrin from epichlorohydrin containing technical impurities, by fractional distillation under particular conditions, preferably with continuous operation, that yield a product of very high purity and very low content of halogenated hydrocarbons. Epoxy resins made with such ultrapure epichlorohydrin are especially well suited for use in fabricating electrical components and microchips. | 2 |
[0001] This application claims priority from provisional application no. 61/184,034, filed on Jun. 4, 2009, and from provisional application no. 61/249,068, filed on Oct. 6, 2009. These two applications are incorporated by reference herein in their entirety.
BACKGROUND INFORMATION
[0002] 1. Field of the Invention
[0003] The invention relates to a porous paver. More particularly, the invention relates to a porous paver and a method of providing a porous pavement.
[0004] 2. Description of the Prior Art
[0005] It is known to use porous pavement to provide pavement that allows stormwater to infiltrate back into the ground naturally, rather than to run off. The porous pavement made with pavers typically includes a method of laying out non-porous pavers to provide a load-bearing pavement surface, with regularly dispersed void areas between the pavers. The non-porous pavers are typically concrete blocks, bricks, or reinforced plastic mats. The void areas are then filled with gravel, sand, or grass turf, which allow the stormwater to infiltrate into the ground.
[0006] Porous pavers or pavement serve their function only if the water can actually pass through the paver or pavement at a minimum specified rate. Porous pavement is known. With time, however, the porosity is substantially diminished, because the porous material becomes clogged with sediment, debris, or other materials that prevent the stormwater from flowing through the pavement. The construction of porous pavement also requires attention to certain temperature parameters. For example, if the porous pavement is laid down and then subjected to freeze-thaw cycles before it is cured, the pavement will crack and crumble. The remedy for dogged or cracked porous pavement is to dig it up and replace it, a costly undertaking.
[0007] What is needed, therefore, is a porous paving system that is readily cleanable, maintainable, or replaceable. What is further needed is such a system, the components of which can be manufactured under controlled conditions.
BRIEF SUMMARY OF THE INVENTION
[0008] The invention is a porous pavement stem that is based on a paver made of porous material, whereby a retrieval means is provided in the porous paver, so as to allow individual porous pavers to be removed from the pavement for cleaning, replenishing, or replacement, as needed. The invention also encompasses a paved surface that is made up of a combination of porous and non-porous pavers, and/or one that uses a hybrid paver.
[0009] The hybrid paver is a bi-material paver block that provides the desired load-bearing properties of conventional non-porous pavers and the desired filtration properties of porous pavement for allowing passage of stormwater through the pavement into the ground. The hybrid paver according to the invention comprises an outer portion that is non-porous and an inner portion that is porous. In other words, the hybrid paver has a donut-like non-porous outer portion and a donut-hole-like porous inner portion. The outer portion includes the entire perimeter of the hybrid paver, is a structural wall around the porous inner portion, the structural wall having the necessary strength characteristics to provide the desired load-bearing strength of the pavement.
[0010] The inner portion is constructed of a porous concrete that provides a specified filtration rate of water, typically stormwater. Additives may be mixed with the porous concrete to filter out specific pollutants. it may be desirable to be able to remove the inner portion from the outer portion for cleaning or replacement. For this reason, the hybrid paver may be constructed as a modular unit from which the inner portion may be readily removed or inserted, In this case, the inner portion is constructed as a cartridge or a modular piece that fits into a cavity in the outer portion. A means for inserting and retrieving the cartridge may be incorporated into the cartridge.
[0011] The inner portion and outer portion are made according to conventional industry standards, such as, for example, ASTM standards, if the paver is made of concrete. Each portion of the paver provides the desired load-bearing capability, The inner portion may also be used as a stand-alone porous paver, that is, does not have to be inserted into an outer portion, but may instead be inserted into a cavity that is created by a particular layout configuration of other porous and non-porous pavers.
[0012] The pavers used in the porous pavement system according to the invention may be any suitable shape and size. Thus, for example, pavers may be constructed as large slabs, as small regularly shaped blocks, or as decoratively shaped elements. Depending on the size and shape of the payers, the retrieval means may also be adapted to be coupled to a lifting means that is incorporated into a vehicle that is equipped with some type of hoisting or lifting mechanism, to assist in lifting the paver from the pavement surface or, in the case of large slab-like pavers, also to install the paver.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements, The drawings are not drawn to scale.
[0014] FIG. 1 is a top plane view of the hybrid paver according to the invention.
[0015] FIG. 2 is a side elevational view of the hybrid paver of FIG. 1 , showing a grid-like cradle for a single paver.
[0016] FIG. 3 is a cross-sectional view through the center vertical plane of the porous cartridge.
[0017] FIG. 4 is an illustration of the retrieval means.
[0018] FIG. 5 is a bottom plane view of the porous cartridge.
[0019] FIG. 6 is an exploded view, illustrating the assembly of the retrieval insert and the use of a tool to remove the porous cartridge from the hybrid paver according to the invention.
[0020] FIG. 7 is a multi-paver cradle, showing keys for locating pavers.
[0021] FIG. 8 illustrates a hybrid paved surface formed by an alternating layout of non-porous pavers and porous pavers.
[0022] FIG. 9 illustrates a porous paved surface.
[0023] FIG. 10 illustrates a retrieval means for large-slab porous pavers.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present invention will now be described more fully in detail with reference to the accompanying drawings, in which the preferred embodiments of the invention are shown. This invention should not, however, be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be complete and will fully convey the scope of the invention to those skilled in the art.
[0025] FIGS. 1-5 illustrate the elements of a hybrid paver 100 according to the invention, which comprises a non-porous paver 10 , a porous paver 20 . The non-porous paver 10 is constructed of a conventional non-porous concrete, which has the desired strength and compression properties for the intended use. As seen in FIG. 1 , the non-porous paver 10 has an open center portion that receives the porous cartridge 20 . The porous paver 20 is constructed of a porous or pervious concrete or other porous material, according to established industry standards, and allows water, for example, stormwater, to pass through the paver at a given rate. For example, concrete made according to ASTM C941C94M is a pervious concrete made with aggregates coarse enough to allow water to pass through the concrete to the substrate below and strong enough to be traffic bearing. It is also possible to provide a hybrid paver 100 wherein the non-porous paver 10 has a higher compression strength than that of the porous paver 20 , in which case the height dimension of the porous paver 20 may be slightly less than that of the non-porous paver 10 . Conventional porous paving material has a height dimension that is greater than that of a non-porous material that provides a corresponding compression strength. Using the hybrid paver 100 according to the invention enables the implementation of a porous paving system in which the height dimension is determined by the strength characteristics of the non-porous paver 10 , and thus, the use of a paver that is lower in height than would be expected with conventional porous paving material.
[0026] In the embodiment shown in the figures, the porous paver 20 is shown as a porous cartridge that is selectively insertable into and removable from the non-porous paver 10 . The porous paver 20 , being constructed according to industry standards, may also serve as a paver without the non-porous paver 10 .
[0027] FIGS. 3-6 illustrate details of a retrieval means 30 that may be used to facilitate insertion and removal of the porous paver 20 into the non-porous paver 10 . Porous concrete may become plugged with debris that reduces or blocks the rate of filtration of water through it. The porous cartridge is provided with the retrieval means 30 , to facilitate removing the porous cartridge 20 from the non-porous paver 10 , for purposes of replacement, replenishing, or cleaning. FIG. 3 is a cross-sectional view along the vertical plane shown in FIG. 1 . A through-bore 32 with a cross-groove 34 is provided through the porous paver 20 that is constructed to receive the retrieval means 30 , which, in the embodiment shown, includes a bar 38 assembled in a sheath 36 . The retrieval means 30 is inserted into the porous paver 20 through the cross-groove 34 in the bottom of the porous paver. A tool T shown in FIG. 6 may be inserted into the porous paver 20 from the top face, such that the hook portion of the tool T engages the bar 38 . The porous paver 20 may then be lifted out of the non-porous paver 10 .
[0028] In the embodiment shown, the retrieval means 30 is illustrated together with the porous paver 20 and the non-porous paver 10 . It is understood that the porous paver 20 does not have to be used as a cartridge, but can be used as a stand-alone paver.
[0029] In this embodiment, a cradle 40 is provided to hold the non-porous paver 10 and the porous paver 20 together as a single unit. The cradle 40 facilitates handling and placement of the pavers. The cradle 40 may also serve to ensure proper spacing between pavers 100 when they are laid out. In the embodiment shown in FIGS. 1 and 2 , the cradle is a shallow rectangular container which is dimensioned to hold the non-porous paver 10 and the porous paver 20 . Ideally, the cradle 40 has an open structure, to allow water to pass through it. The cradle 40 may have another construction, for ornamental or functional reasons. For example. the cradle may have a half-high wall that separates the non-porous paver 10 from the porous paver 20 so as to create a space between the two elements, or may be constructed as a bottom flange that extends into the through-bore 32 and connects to or is integrally formed with the retrieval means 30 . The cradle 40 thus supports the non-porous paver 10 around the porous paver 20 . The material used to construct the cradle 40 is not considered within the scope of the invention. Any suitable material, with the required strength and rigidity properties to support the non-porous paver 10 and the porous paver 20 may be used.
[0030] FIG. 7 illustrates another embodiment of the cradle 40 , a multi-paver cradle. The cradle 40 has a bottom support and is large enough to receive and support a plurality of pavers. The bottom may be constructed as a grid, as described above, or in some other manner, so as to allow water to pass through it relatively unhindered, and the perimeter may be provided with a lip that hinders a translational motion of the pavers. In the embodiment shown, the cradle 40 is dimensioned to accommodate four hybrid pavers 100 , the dashed lines indicating the locations of four hybrid pavers 100 A- 100 D. This is by way of illustration only. It is understood, however, that, depending on the size and shape of the pavers, and the type of equipment used to handle the multi-paver cradle 40 , a number of pavers 100 other than 4 may be assembled on the cradle. A guide 42 may be provided on the cradle 40 to aid in holding the hybrid pavers 100 in place. The guide 42 may be a key or ridge; the bottom surfaces of the inner pavers 20 and the outer pavers 10 would then have a corresponding groove or slot. An advantage of the multi-paver cradle 40 is that it greatly enhances the structural stability of a paving system and facilitates handling and installation. The cradle 40 may be handled as a single unit, in which case, four pavers 100 can be moved, handled, or installed as a single unit. The cradle 40 with the pavers 100 A- 100 D provides much greater stability when installed as a paving system, because the weight of a multi-paver unit provides much greater resistance to tipping. For example, a load applied to a corner of a paver that is individually placed in the paving system may result in the paver tipping. A load applied to a corner of a paver that is assembled on a multi-paver cradle will be much less likely to result in tipping, because of the total weight and the distribution of weight across a much greater area. Also, a shifting of a paver within a paving layout is much less likely, because of the constraint of the cradle, For example, a force applied laterally to one paver is less likely to shift the paver, because it is constrained within the cradle and keyed in position.
[0031] In the embodiments described herein, the non-porous paver 10 and the porous paver 20 are constructed of concrete. It is understood, however, that other suitable materials may be used, for the non-porous paver, for the porous paver, for both. Also, the non-porous paver and the porous paver may be made of different materials. Thus, it is possible to make the non-porous paver of brick or a manufactured stone, and the porous paver of pervious or porous concrete, or any suitable porous material, such as recycled glass, tires, asphalt, and combinations of material.
[0032] The hybrid paver 100 has been illustrated as a two-component paver. It is considered within the scope of this invention to also provide the paver 100 as a unitary paving block having an outer non-porous paver portion 10 and an inner porous paver portion 20 .
[0033] The shape of the pavers 100 is irrelevant. A rectangular hybrid paver 100 is shown in the drawings herein, but it is understood that any suitable shape, whether the shape be chosen for ornamental or functional reasons, may be used.
[0034] FIG. 8 illustrates a hybrid paved surface 200 according to the invention comprising the non-porous paver 10 and the porous paver 20 . The hybrid paved surface 200 is created by laying the pavers 10 and 20 in an alternating pattern. The particular shape of the pavers 10 and 20 shown here is for illustration purposes only. In the embodiment shown, a conventional paver has four recesses formed about its perimeter. Four adjacent pavers together form an approximately circular opening 210 . The porous paver 20 is placed in this opening 210 . The porous paver 20 includes the retrieval means 30 described above. The particular shape of the pavers 10 is not relevant to the invention. For example, rectangular or square pavers 10 may be laid out in a configuration that creates an space 210 into which the porous paver 20 is inserted.
[0035] FIG. 9 illustrates a porous pavement surface hat is not necessarily a hybrid surface, as described above, but instead. may be made up primarily of porous pavers 20 . The embodiment shown uses large-slab porous pavers 20 , Such large-slab pavers are heavy and difficult to handle. Being porous, it is also possible or desirable, that such porous pavers 20 be cleaned or replaced. Depending on the size of the paver, one paver may be too heavy to handle manually. FIG. 10 illustrates a further embodiment of the retrieval means 30 , one that is well suited for manipulating, i.e., retrieving, lilting or lowering large, heavy pavers 20 . Reference is made in the following description to porous pavers 20 , but it is understood, that is possible to provide non-porous pavers 10 with the same retrieval means 30 , and any description of the retrieval means 30 with reference to porous pavers 20 shall also apply to non-porous pavers 10 . One or more lifting receptacles or lifting lugs 31 are embedded into the paver 20 . The number and the location of the lugs 31 depends on the size and shape of the pavers 20 . Four lifting lugs may be provided in a large rectangular paver; three or two or only one lug may be provided in smaller pavers. The lifting lugs 31 are constructed so as to be able to support the weight of the paver and withstand downward forces and are devices that are ideally countersunk into the pavers. The area around the countersink is capped with some suitable closure means 39 , so as to provide a closed upper surface on the paver. There are many possible and acceptable constructions for the lifting lugs 31 . For example, the receptacle 31 may be a threaded insert that is embedded in the paver, or may be a keyed opening that will receive and constrain some tool or device that is inserted into the opening. A lifting mechanism 33 for lifting the pavers is couplable with the one or more lifting receptacles or lugs 31 . One embodiment of the lifting mechanism 33 is shown only schematically in FIG. 9 . It is understood that various types and configurations of lifting devices maybe used. One such suitable lifting mechanism is a hook suspended from a cable that is couplable with an attachment means 37 and that is operated by means of some conventional equipment that is typically used to lift heavy items in the construction industry, such as a tractor, or front-end loader, or a vehicle with a hoisting capability. The attachment means 37 may be specially constructed for a particular type of paver with a particular configuration of lifting lugs, such as the spider-like device shown in FIG. 9 . The spider 37 has at least the number of legs 37 ′ that corresponds to the number of lugs 31 . Each leg 37 ′ is attached to a corresponding one of the lifting lugs 31 . Alternatively, the attachment means 37 may be a set of cables, each cable connectible at one end to a lifting lug and at the other end to the lifting mechanism.
[0036] It is understood that the embodiments described herein are merely illustrative of the present invention. Variations in the construction of the hybrid paver and/or the porous paved surface may be contemplated by one skilled in the art without limiting the intended scope of the invention herein disclosed and as defined by the following claims. | A porous pavement system and a method of maintaining the porous pavement system are disclosed. A combination of porous and non-porous pavers are laid out to create a porous pavement. A receptacle or retainer for receiving a tool is in incorporated into the porous pavers, to facilitate lifting the pavers by means of the tool. A cradle may be used to hold multiple pavers. | 4 |
BACKGROUND OF THE INVENTION
This invention relates generally to a retainer providing preload force for a bearing supporting a rotatable shaft and, more particularly, to a clamping ring providing a resilient preload so as to maintain an axial compressive rebound force on the bearing.
While this invention may be employed in many fields, it is particularly useful in conjunction with drive assemblies for heavy-duty earthmoving equipment, such as crawler tractors and the like. The final drive and the traction chains spaced on each side of the crawler tractor are subjected to substantial radial and axial thrust loads. These loads are the result of the high driving force required for operation and the erratic loading placed on the tractor drive because of rough terrain, side hill operation and directional changes.
In order to provide sufficient friction free support for the highly-loaded rotatable drive shafts, shock resistant, heavy-duty, tapered roller bearings are employed. If properly arranged and preloaded, these tapered roller bearings have inherent capability to efficiently accommodate both radial and axial thrust loads. In order to withstand high stress loads and deflection of components, it is vital that the required preloads on the tapered roller bearings be maintained so as to provide rigidity, positive support and extended service life for the bearings and the associated components.
In the prior art, it is a common practice to place a lock nut onto the rotating shaft to bear against the bearing and maintain prescribed bearing preloads. However, a conventional lock nut has a tendency to work loose during operation so that the bearing preload is diminished. In general, rotation of the lock nut ten degrees will alter the breakaway torque of the lock nut by approximately 100 foot-pounds.
It is possible to make periodic inspections and service adjustments of the bearing and lock nut. In some applications, ready accessibility makes these inspections and adjustments expedient. Even when the bearings and the lock nuts are not readily accessible, prudent inspections and periodic service should not be ignored. In the case of crawler-type tractors where the track chains and the drive sprockets must be removed, such periodic inspections are conducted at great expense. However, if service adjustments to the bearings and lock nuts are not made, serious damage and total failure of major components can result before operators or service personnel even become aware of the problem.
In order to eliminate the need for periodic servicing, numerous means have been devised to maintain the lock nut in fixed position on the shaft so that the bearing will be subjected to a constant preload force. Lock nuts have been employed which include integral synthetic plastic rings and/or plastic washers for securely gripping the coacting threads on the shaft. However, shaft deflection under high loads may cause this type of lock nut to loosen thereby resulting in partial or complete loss of vital bearing preloads.
A lockwasher which is fixedly secured to the lock nut is available, but is relatively expensive. The lockwasher has internal serrations to prevent rotation of the lockwasher on the shaft and tangs to engage the specially-designed lock nut. A key has been utilized between keyways formed in the lock nut and in the shaft to prevent relative rotation of the lock nut. A threaded split nut has been utilized. The use of shims in conjunction with a plate fixed to the shaft has also been employed to provide correct positioning of the bearing.
The above methods for obtaining and retaining a preload on the bearing securely fix the bearing against axial movement in one direction relative to the shaft. However, it has been found that it is desirable that the retainer or lock nut providing the preload force for the bearing have a degree of resiliency capable of maintaining an axial compressive rebound force even when it is loosened slightly. This compressive rebound force maintains a preload on the bearing races which is capable of assuring continued operating efficiency. Conventional lock nuts are not usually capable of providing this axial compressive rebound force.
SUMMARY OF THE INVENTION
The present invention is directed to overcoming one or more of the problems as set forth above.
According to the present invention, a bearing disposed about and rotatably supporting a shaft is held in preloaded position by a retainer having an axial bore with a wall in which circumferential grooves are formed so as to define alternating axially-spaced grooves and lands. The shaft, in turn, has a circumferential surface with spaced grooves formed therein so as to define alternating axially-spaced grooves and lands adjacent the desired preloaded position of the bearing. The retainer is moved radially into engagement with the shaft so that the respective coacting grooves and lands mesh, thereby securing the retainer to the shaft and resiliently securing the bearing against substantial axial movement.
One or both of the retainer and the shaft has sloped grooves and lands which are oblique to the shaft axis. Elastic deflection and deformation of the lands is effected by tightening the retainer on the shaft. The utilization of coacting distortable or deflectable sloped and annular ribs and lands provides a degree of resiliency capable of maintaining an axial compressive rebound force. An interference fit of the interleaved lands and grooves of the clamping ring and the shaft eliminates the need for close matching of the components.
In an exemplary embodiment of the invention, the clamping ring is formed from a plurality of separable sections. Means are provided for securing the sections together and for moving the sections radially inward so as to constrict the opening through the clamping ring and tighten the clamping ring on the shaft. Because of the radial shifting capability of the clamping ring sections, simple hand or pneumatic-actuated power wrenches can be utilized to secure the clamping ring on the shaft while press means axially applies the bearing preload.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of a crawler tractor final drive partially in section in which a prior art self-locking retainer nut is employed to axially fix the inner race of a tapered roller bearing on a shaft;
FIG. 2 is a plan view of a retainer ring constructed in accordance with the invention which is operative to axially fix the inner race of the tapered roller bearing;
FIG. 3 is a fragmentary enlarged cross-sectional view of a bearing with the clamping ring in an unloaded position prior to the engagement of the sloping grooves and lands of the drive shaft;
FIG. 4 is a fragmentary enlarged cross-sectional view similar to FIG. 3 with the clamping ring securely engaged with the sloping grooves and the lands of the drive shaft; and
FIG. 5 is a fragmentary enlarged cross-sectional view of an alternative embodiment of the invention in which the slope of the corresponding lands and grooves has been reversed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, a final drive assembly for a crawler tractor, generally designated 10, is seen to broadly include a steering clutch 11, a pinion gear 13 fixed on a shaft 14, a gear 16 which meshes and is rotated by the pinion gear 13, a sprocket drive shaft generally designated 17, fixed to the gear 16 and rotated thereby, a sprocket wheel 19 fixed to the drive shaft 17, and a complementing traction chain 20 driven continuously by the sprocket wheel 19. The tractor engine (not shown) provides power to the steering clutch 11 for operating the sprocket wheel 19.
The sprocket drive shaft 17 is journaled on one side of the gear 16 by suitable bearings 22 carried by the final drive housing 23. On the opposite side of the gear 16, the drive shaft 17 is supported by a tapered roller bearing assembly, generally designated 26, carried by the drive housing 23. The bearing assembly 26 has high radial and axial thrust load capability. The bearing assembly 26 includes an inner bearing 27 and an opposed outer bearing 28. The inner bearing 27 has an inner cone race 30 seated against an internal shoulder 31 formed in the drive shaft 17, an outer cup race 33 seated against a shoulder 34 of the drive housing 23, and tapered rollers 36 which are held in operative position between the cone race 30 and the cup race 33. Similarly, the outer bearing 28 has an inner cone race 38, an outer cup race 39, and tapered rollers 40.
In the prior art, a lock nut 42 was threaded onto the drive shaft 17 as seen in FIG. 1 so as to bear against the outboard end of the cone race 38 in order to provide the required preload on the bearing assembly so as to obtain positive support for the drive shaft 17. The sprocket wheel 19 is positioned outboard of the lock nut 42 and is fixed to the drive shaft 17 against rotation relative thereto via axially-extending splines 43. The sprocket wheel 19 is fixed against outward axial movement by a lock nut 45 which is threaded onto the outer end of the drive shaft 17 and bears against the sprocket wheel 19.
FIG. 2 illustrates a clamping ring or retainer, generally designated 50, which, in accordance with the invention, is employed in lieu of the lock nut 42 shown in the prior art structure of FIG. 1. With the exception of this substitution for the lock nut 42, a final drive assembly incorporating the invention is constructed in the manner as illustrated in FIG. 1. The clamping ring 50 is seen to include a pair of semicircular ring sections 51 and 52 which define an internal bore 54 when assembled. Each of the ring sections 51 and 52 includes radially-extending portions 56 and 57 through which bolts 60 and 61, respectively, extend to secure the ring sections 51 and 52 together.
As best seen in FIG. 3, a series of axially-spaced circumferential annular grooves 63 are formed in the wall of the bore 54 so as to define a surface having alternately axially-spaced grooves 63 and ribs or lands 64. The grooves 63 and therefore the lands 64 have a rectangular cross section and a prescribed radial depth.
Formed in the circumferential surface 66 of the drive shaft 17 adjacent the desired position of the outer end 67 of the cone race 38 is a series of axially-spaced grooves 69 which, in turn, define a series of axially-spaced ribs or lands 70. The grooves 69 and therefore the lands 70 have a parallelogram cross-section, the grooves 69 sloping radially inward and axially inward from the circumferential surface 66 so that they are disposed oblique to the shaft axis.
In FIG. 3, one section of the clamping ring 50 is being installed and is loaded by suitable press means indicated by arrow 72. The press means 72 forcefully urges the clamping ring 50 and therefore the cone race 38 inwardly to the desired preloaded position. When the clamping ring 50 is sufficiently loose on the drive shaft 17, the press means 72 can readily shift the outer bearing 28 and the clamping ring 50 axially inward without interference. When the loosely-coupled clamping ring 50 is properly positioned with the grooves 63 and the lands 64 of the clamping ring 50 being aligned with the respective lands 70 and grooves 69 of the drive shaft 17, the bolts 60 and 61 are tightened with sufficient torque to move the ring sections 51 and 52 together to effect engagement of the respective grooves and lands of the drive shaft 17 and the clamping ring 50. The inner surface 74 and the outer surface 75 of the clamping ring 50 are smooth to permit the clamping ring 50 to move radially inward towards the drive shaft 17 with relative ease regardless of the press force being employed.
As shown by FIG. 4, predetermined tightening of bolts 60 and 61 effects elastic deflection of the straight lands by the angled or sloping grooves 69 and lands 70 of shaft 17. Regardless of how many straight and sloped lands and grooves are employed to obtain the reaction loading force, the coacting relatively shallow grooves and lands must be of sufficient depth to result in a prescribed level of axial deflection of the straight lands 64. With sufficient elasticity and rebound, the displaced lands 64 will maintain a relatively high level of compressive force to keep the bearing assembly 26 properly preloaded. Disengagement of the coacting lands and grooves is unlikely because the bolts 60 and 61 are tightened with substantial torque and the deflected lands 64 of the clamping rings 50 are in shear radially and therefore tend to retard direct tensile loading and yielding of bolts 60 and 61.
The deflection required from the sloping and elastically displaced angular lands 64 need only be sufficient to compensate for any limited fatigue or yielding of the bolts 60 and 61 and any inherent tendency for the elastically displaced lands 64 to take some limited permanent set. Even with some yielding of the bolts 60 and 61 and some permanent setting occurring in the lands 64, sufficient rebound capability in the material will afford continuance of desired preloads on the tapered roller bearing assembly 26.
FIG. 5 illustrates how the angular or sloped and straight lands and grooves can be reversed in the coacting shaft 17' and clamping ring 50' while the elastic deflection are rebound force for maintenance of bearing preloads remains the same.
Elastic deflection of the angular and straight lands by tightening of bolts 60 and 61 will generate a rebound force ranging from 7,000 to 10,000 pounds axial preload on one or dual coacting tapered roller bearings. Preferably, the clamping ring 50 is made of softer material than the supporting shaft 17, and can even be made of material other than metal. Either the entire ring or just the lands can be made of metal or other synthetic man-made materials as long as a deformable material with elastic rebound capabilities is used. The interference fit of the interleaved lands and grooves of the clamping ring and reacting surface requires no close machining. Because of radial shifting capability of the ring sections, present simple hand- or pneumatic-actuated power wrenches can be utilized to secure the clamping rings under the bearing preload. | A retainer for resiliently applying a preload force to a bearing assembly rotatably supporting a shaft has a bore through which the shaft extends and is assembled from a plurality of separable sections. Formed in the wall of the bore are circumferential grooves which define lands therebetween. Similarly, circumferential grooves are formed about the shaft adjacent the end of the bearing assembly. One series of grooves are oblique to the shaft axis so that the respective lands are deflectively engaged when the retainer is radially closed about the shaft. The retainer is advantageously employed to maintain preloads on tapered roller bearings supporting the final drive shafts in heavy earthmoving equipment. | 5 |
BACKGROUND OF THE INVENTION
[0001] The present disclosure generally relates to portable equipment and in particular an apparatus for providing postural support and improved ventilation to a user while carrying portable equipment.
[0002] An ideal posture, also referred to as a neutral posture, may result from a proper alignment of the spine. The ideal posture may provide a wide variety of benefits, such as a lower amount of energy may be required to maintain any desired position and movement may facilitated within optimal bio-kinematic ranges. Achieving and maintaining the ideal posture may also reduce the stress placed on the body's tissues (for example, see Danis, C. G.; Krebs, D. E.; Gill-Body, K. M.; Sahrmann, S. (1998), Relationship between standing posture and stability , Journal of the American Physical Therapy Association, pp. 502-517). The ideal posture may also optimize breathing, oxygenation and circulation of bodily fluids such as lymph, cerebral spinal fluid, and blood.
[0003] Postural alterations or modifications that deviate from the ideal posture are known to be associated with numerous afflictions such as: general pain syndromes (for example, low back pain, neck pain, headaches); problems with specific joints (for example the hip and knee); problems with specific spinal regions (for example, loss of normal low back curve, cervical kyphosis and a reversal of normal neck curvatures); and various organ ailments (for example, uterine prolapse, gastric herniation, and impaired respiratory function). Postural alternations may also affect morbidity and mortality (for example, see Kado D M, Huang M H, Karlamangla A S, Barrett-Connor E, Greendale G A. Hyperkyphotic posture predicts mortality in older community-dwelling men and women: a prospective study. J Am Geriatr Soc 2004;52:1662-1667; 28 Milne J S, Williamson J. A longitudinal study of kyphosis in older people. Age and Ageing 1983;12:225-233 and Anderson F, Cowan N R. Survival of healthy older people. Br J Prey Soc Med 1976;30:231-232).
[0004] The carrying of portable equipment may cause, or exacerbate, a person to deviate from the ideal posture. For example, soldiers and law enforcement personnel often wear personal body armor. Due to the rigid nature and necessary weight of the armor, to provide the desired protection, users of body armor often complain about lack of comfort and various ailments, which may be linked to deviating from the ideal posture.
SUMMARY OF THE INVENTION
[0005] A postural support apparatus is described further below. The apparatus comprises a biasing body which includes a top member, a bottom member spaced from the top member, and left and right resilient members attached at each end of the top and bottom members. The left and right resilient members are configured to bias the top and bottom members into a predetermined position. The support apparatus further includes a removable load distributor connected to the biasing body configured to distribute a load force applied to the postural support apparatus. A stabilizer is provided to link the left and right resilient members.
[0006] The apparatus may improve the comfort and posture of a user while carrying portable equipment. For example, the apparatus may be attachable to, or integrated with, various portable equipment including: personal body armor, backpacks, fire resistant equipment and clothing, respiratory systems, gas tanks and the like. Carrying such portable equipment may cause the user to deviate from an ideal posture. For example, personal body armor often includes storage pockets for ancillary equipment, such as ammunition and the like, on the front for ease of access. The rigidity of the armor, the overall weight of the armor and any ancillary equipment, an unequal weight distribution, and prolonged exposure are various factors that may contribute to a user deviating from the ideal posture.
[0007] The biasing member (resilient members) may bias the apparatus and the user towards a neural spine position while carrying portable equipment. Further, the load distributor may more evenly distribute the weight of the portable equipment through the user's lumbar region as well as lift weight off the user's shoulders.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a dorsal view of an example postural support apparatus, in accordance with one embodiment of the present invention;
[0009] FIG. 2 is a ventral view of the postural support apparatus shown in FIG. 1 ;
[0010] FIG. 3 is a dorsal view of the resilient unitary body portion of the postural support apparatus shown in FIG. 1 ;
[0011] FIG. 3 a is a side view of the resilient unitary body portion of the postural support apparatus shown in FIG. 1 ;
[0012] FIG. 4 is a dorsal view of the biasing body portion of the postural support apparatus shown in FIG. 1 .
[0013] FIG. 5 is a side view of the biasing body portion of the postural support apparatus shown in FIG. 1 .
[0014] FIG. 6 is a dorsal isometric view of the stabilizer portion of the postural support apparatus made in accordance with the invention.
[0015] FIG. 7 is a ventral isometric view of the stabilizer portion of the postural support apparatus shown in FIG. 6 .
[0016] FIG. 8 is an isometric view of the postural support apparatus shown in FIG. 1 .
[0017] FIG. 9 is an isometric view of a lumbar support unit for use with the postural support apparatus shown in FIG. 8 .
[0018] FIG. 10 is a side view of the postural support apparatus shown in FIG. 8 with the lumbar support unit shown in FIG. 9 attached thereto.
[0019] FIG. 11 is a sectional view of a person wearing the postural support apparatus of the present invention under body armor.
[0020] FIG. 12 is ventral view of a body armor carrier having the postural support apparatus of the present invention incorporated therein.
[0021] In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
[0022] Referring firstly to FIG. 1 , one embodiment of a postural support apparatus made in accordance with the present invention is shown generally as item 10 and includes a biasing body 11 mounted to a load distributor 20 . The biasing body 11 has opposite top end 14 and bottom end 12 and opposite sides 16 and 18 . Load distributor 20 has lower portion 24 and upper portion 22 which are configured to securely retain bottom ends 12 and top end 14 , respectively. Vent member 26 is coupled to both portions 22 and 24 at opposite ends thereof. Load distributor 20 is made of a flexible and strong fabric and, preferably, vent member 26 is made of a fabric mesh which is capable of permitting air and moisture to pass there through. Sides 16 and 18 are flexible and resilient so as to bias portions 22 and 24 into a predetermined position (see FIG. 10 ) and keep vent member 26 taught.
[0023] Referring now to FIG. 3 , biasing body 11 preferably comprises a single unitary spring like member. Body 11 could be formed as any spring like material such as fiberglass, plastic, carbon fiber, metal or composites thereof. Most preferably, body 11 consists of a loop of large gauge metal wire which is both resilient and flexible: essentially a large wire spring. Top end 14 of body 11 is formed as two lobes 32 and 34 with arched portion 36 between them which extends towards bottom end 12 . Resilient sides 16 and 18 are bent towards each other at points 28 and 30 , respectively, so that the space separating resilient sides 16 and 18 is narrowest at those points. This narrowing of the separation between the resilient sides permits body 11 to flex from side to side with greater ease. As best seen in FIG. 3 a , body 11 is arched so that ends 14 and 12 are biased towards a predetermined position to form an arch with centre portion 29 positioned at the apex of the arch. As shall be discussed below, this arched shape permits the formation of an air space between the user's back and body 11 . As can be seen in FIG. 4 , a stabilizer 38 is positioned at center portion 29 to provide additional structural support. Portions 28 and 30 of biasing body 11 are secured around stabilizer 38 to secure the stabilizer and prevent center portions 28 and 30 from moving relative to each other which might cause collapse of the arch formed in biasing body 11 .
[0024] Referring now to FIGS. 6 and 7 , stabilizer 38 preferably consists of a plastic member having opposite ends 40 , central body 39 and tabs 42 positioned at ends 40 . One side of central body 39 has a raised portion 44 which is configured to fit in gap 46 of articulating body 11 (see FIG. 3 ). Ends 40 and tabs 42 are configured to permit the stabilizer to be threaded into the biasing body 11 such that the stabilizer is held securely by tension and raised portion 44 prevents the two sides of body 11 from physically touching.
[0025] Referring back to FIG. 1 , bottom portion 24 of load distributor 20 has a pocket 46 which is dimensioned and configured to snugly retain end 12 of biasing body 11 . Likewise, top portion 22 of load distributor 20 is provided with pockets 48 and 50 to snugly receive the lobes of end 14 of biasing body 11 .
[0026] Referring to FIGS. 1 and 2 , adjustable straps 52 and 54 are provided between upper and lower portions 22 and 24 to permit a user to adjust the distance between the upper and lower portions of the load distributor by pulling on tabs 56 and 58 . Ideally, the lengths of straps 52 and 54 are adjusted to keep vent member 26 taught.
[0027] Upper portion 20 is provided with shoulder extensions 60 and 62 , which preferably consist of stiff but flexible extensions which help to distribute part of the weight born by the postural support apparatus off of the user's shoulders. Lower portion 24 is provided with an adjustable strap attachment 66 and upper portion 22 is provided with adjustable straps 65 for attaching to a body armor carrier or the like. Both portions 22 and 24 are provided with pads 64 to help make the postural support apparatus comfortable when worn.
[0028] Referring now to FIGS. 8, 9 and 10 , a lumbar support member 68 can be provided which is releasably attachable to portion 24 by straps 70 . As mentioned previously, air gap 72 is formed by the arch of biasing member 11 between the biasing member 11 and vent member 26 .
[0029] Referring now to FIG. 11 , user 78 can wear postural support apparatus 10 under body armor carrier 76 . When so worn, the weight of the body armor and other equipment (not shown) carried on body armor carrier 76 is distributed more or less equally along the user's back 74 by means of upper portion 22 , lower portion 24 and vent portion 26 . Some of the weight is lifted off of the user's shoulders 80 by the extensions on the upper portion. Air gap 72 is maintained by biasing member 11 so that the user's back remains cool. Being flexible, postural support apparatus 10 can move and articulate while the user moves about. The resilient spring like nature of biasing member 11 ensures that the weight of the load is always distributed along the user's back and shoulders more evenly regardless of how the user moves. As shown in FIG. 12 , a body armor carrier 100 can be constructed with postural support apparatus 10 pre-attached by means of stitching 110 and 112 or by other means known generally in the art such as adhesive bonding or zippers. This forms an integral structure which can be easier to use and which will have less play as the postural support apparatus will be more tightly held to the body armor carrier.
[0030] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. | A postural support apparatus comprising is provided including an biasing body comprising: a top member; a bottom member, spaced from the top member; and a left and right resilient members attached at each end of the top and bottom members. The left and right resilient members are configured to bias the top and bottom members into a predetermined position. The support apparatus also includes a load distributor connected to the biasing body configured to distribute a load force applied to the postural support apparatus. | 5 |
TECHNICAL FIELD
This invention pertains to the field of sending and receiving electronic messages, such as e-mails, in communications networks.
BACKGROUND ART
Electronic messaging has become an essential form of communication in the age of the Internet. With the surge in usage of electronic media, such as e-mail, an increased burden has been placed on the resources needed to manage this data traffic, including data storage devices. Efficiencies in this area have come from many sources, including the technology described in the invention protected by U.S. Pat. No. 5,815,663 (Distributed posting system using an indirect reference protocol), referred to herein as “dynamic content”.
One shortcoming of dynamic content technology, as applied to e-mail, is that all mail sent to multiple recipients assumes that recipient mail clients are enabled to read dynamic content mail. The present invention removes this requirement by moving the responsibility of dealing with dynamic content out of the mail client and into the outbound-and inbound mail servers. Thus, all mail clients are now able to participate in the advantages of dynamic content without requiring any modifications to the client.
DISCLOSURE OF INVENTION
This invention eliminates redundant electronic messages in a network caused by copying a message to multiple recipients without requiring code changes in the messaging client code. Specifically, a message sent by a user messaging client, such as an e-mail client, is received by a receiving server, such as an SMTP server, which then stores the message content with a content server. The content server returns a pointer to the content, as described in U.S. Pat. No. 5,815,663, which the receiving server then may insert into the message header, in place of the message content, before sending the message to the message recipients. When a recipient receives a message and wishes to read it, the associated inbound messaging server, such as an IMAP or POP mail server, uses the pointer contained in the message to retrieve the message content and return it to the recipient.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other more detailed and specific objects and features of the present invention are more fully disclosed in the following specification, reference being had to the accompanying drawings, in which:
FIG. 1 is a flowchart illustrating a process of reading a message according to the present invention.
FIG. 2 is a flowchart illustrating a process of sending a message according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred implementation is for electronic mail and includes an SMTP server, and IMAP server (collectively, “mail servers”) and a content server communicating with the mail servers via HTTP. In all that follows, our preferred implementation is based on the Apache James Server (see http://james.apache.org/ for details), modified to support the functionality as described herein. We define the operation of the outbound-(SMTP) and inbound (IMAP/POP) servers separately.
SMTP server
When a message is sent to the SMTP server, the server first checks to see which of the recipients are to be sent dynamic content; for example, this could be done via a configuration option. For recipients who are NOT to receive dynamic content, the server simply performs the usual SMTP functions and forwards the message to the appropriate mail relay server for that recipient. If the recipient is to receive dynamic content, the SMTP server sends to the content server one RECEIVE CONTENT request for each content component in the message and the content server returns pointers to the locations of the respective content components on the server; see the Appendix for the format of the RECEIVE CONTENT request. The pointer information includes numeric values corresponding to the content components in the content server database. This pointer information, along with the name and port number of the content server, are added to the mail message header and the header is sent to the recipient. Note that the message body is empty, in this implementation.
See FIG. 2 : Sending a message.
IMAP/POP server
When a user of a mail client wishes to view a mail message in the user's inbox, the user typically selects the message to be viewed from within a window that displays certain summary information about the message, such as the date received, the sender e-mail address or name, and the message subject. The mail client sends a request to the IMAP or POP server to retrieve the message body and this in turn causes the IMAP/POP server to query the message header for dynamic content information. If there is none, it is assumed that the message requested does not contain dynamic content and the IMAP or POP server performs the usual function of fetching and returning the content. If the pointer information is present, it is retrieved and used to format a FETCH CONTENT request (described in the Appendix) to the content server, who returns the desired content. Similarly, if a dynamic content attachment is selected for viewing, the pointer for the attachment is used in the FETCH CONTENT request.
See FIG. 1 : Reading a message.
The above description is included to illustrate the operation of the preferred embodiments, and is not meant to limit the scope of the invention. The scope of the invention is to be limited only by the following claims. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the spirit and scope of the present invention. | A method for reducing the total amount of disk space used by multiple recipients of an electronic message in a communications network. | 7 |
TECHNICAL FIELD
The present invention relates generally to endoscopic instruments and relates more specifically to an improved endoscopic instrument that allows for adjustability of the handles to facilitate a variety of medical procedures, accommodates variations in hand span sizes and grip styles, and easily facilitates cleaning, sterilization and reuse.
BACKGROUND OF THE INVENTION
Endoscopic surgery has recently become a widely practiced surgical procedure. One type of endoscopic surgery, laparoscopic surgery, generally involves a small incision such as through the navel and abdominal wall to view or operate on organs or tissue located in the abdominal cavity. A camera or lens is placed in the area to aid the surgeon in guiding the endoscopic instrument to the particular area to be observed or operated upon.
Endoscopic instruments typically have a handle, an elongated shaft section and any one of a number of surgical tools attached to the shaft. The tools attached to the shaft are referred to as "end-effectors" and may include, for purposes of reference and not exclusion, needle holders, graspers, dissectors, cutters, and scissors. The movement of the end effectors are typically controlled at the proximal end of the instrument by manipulating the handle or a control mechanism located on the housing or the shaft.
At present, most handle portions of endoscopic instruments are shaped in one of two configurations. The first handle configuration closely resembles the handle of a pair of scissors. The handles are ring-shaped and are fixed to close and open relative to one another such that the end effectors may be properly manipulated. The ring-shaped handles do not provide for any adjustability for variations in hand and finger size. Because the surgeon must place his or her fingers through the handle rings, if the span of the surgeon's fingers is too small or too big to fit between the rings, the surgeon is unable to maintain a proper and comfortable grip on the instrument. A second configuration of the handle portion of endoscopic instruments resembles a pistol grip. This style handle has a portion extending downwardly from the shaft. However, this configuration does not provide for any adjustability for variations in hand sizes. A surgeon with a large hand may find it uncomfortable or cumbersome to properly grip the instrument. Conversely, a surgeon with small hands may not be able to adequately grasp the handle so as to properly hold and support the instrument.
Neither the scissors nor the pistol grip configurations adequately address the needs of surgeons who all have various hand sizes, and grip styles when conducting surgery. There is at present no handle on an endoscopic instrument that adjusts relative to itself to accommodate variations in hand sizes as well as variations in grip styles. Because all users of presently existing endoscopic instruments must grip them in the identical fashion, many surgeons develop cramps or discomfort in their hands or backs after holding the instrument for a period of time. In addition, many surgeons must be forced to grip the instrument in a manner that is uncomfortable to them. Thus, it would be advantageous to have an endoscopic instrument that has adjustable handles to accommodate variations in hand sizes, and grip styles.
In addition, there is no existing endoscopic instrument capable of adjusting tile position of the shaft relative to the handle to accommodate different surgical procedures. There are many surgical applications for an endoscopic instrument. There are four general categories of surgery in which an endoscopic instrument may be used. These include thoracic, general abdominal, urological and gynecological.
With each of these categories of surgery, the shaft is angled with respect to the handle in a different manner. For example, in hernia surgery, the endoscopic instrument used forms an acute angle between the handle and shaft. The acute angle between the shaft and handle enables the surgeon to maneuver the endoscopic instrument through the navel and down the front portion of the patient's abdomen just below the skin to operate. With respect to general abdominal surgery, it is often most desirable to have an endoscopic instrument that has the handles and shaft perpendicular to one another. In gynecological surgery and procedures, the shaft and handle should typically be 180° relative to one another.
As a result of different procedures, the preferred configuration of the endoscopic instruments used in each of these procedures is different. At present, a surgeon is apt to use a different endoscopic instrument for each of the procedures described above. This increases the cost of the surgery for the surgeon, the hospital, the insurance company and ultimately the patient. It would be beneficial for tile surgeon and all concerned to have a single instrument capable of adjusting the handles relative to the shaft that could be used for all surgical procedures described above. This would save surgeons, hospitals, insurance companies and consumers money on health care which continues to increase at a rate much higher than inflation.
Most prior art endoscopic instruments have end effectors that have moving parts such as hinges or linkages of some type. These end effector control linkages protrude from the body of the shaft when the end effector is controlled. This is undesirable because such protrusions tend to catch on tissue and cause unwanted damage. In addition, any deposits of tissue or bodily fluid in the linkage of the end effector make it difficult to clean, sterilize and reuse. It is desirable to have an endoscopic instrument that has end effectors that do not have any operating linkages that contact the patient. Such a feature would enable the end effector and instrument to be easily cleaned, sterilized and reused.
Thus, there is a need for an endoscopic instrument having handles that adjust to accommodate different hand sizes and different grip styles.
There is a further need for an endoscopic instrument having handles that adjust relative to the shaft for use in a variety of different medical procedures.
There is still a further need for an endoscopic instrument that enables the user to lock the jaws of the end-effector without maintaining pressure on the handles.
There is yet a further need for an endoscopic instrument where the operating linkages for the end effectors do not directly contact the patient.
There is an even further need for an endoscopic instrument that is cleanable sterilizeable and reusable.
SUMMARY OF THE INVENTION
As will be seen, the present invention overcomes these and other disadvantages associated with prior art endoscopic instruments. Stated generally, the present provides a handle for an endoscopic instrument, the handle defining an instrument shaft having an end-effector at its distal end. The handle of the invention includes a thumb handle for engaging at least a thumb of the user and a finger handle for engaging at least one of the other fingers of the user. At least one of the thumb handle and the finger handle is capable of at least partial rotation about a central axis of the handle such that when the instrument is in a normal orientation, movement of the thumb handle and finger handle toward one another moves the end-effector toward a first orientation and movement of the thumb handle and finger handle away from one another moves the end-effector toward a second orientation. A first disengagement mechanism is provided which is configured to release the thumb handle or finger handle and allows for arrangement of the thumb handle about the central axis independent of the movement of the end-effector. The disengagement mechanism works such that when the mechanism is operated, the distance between the thumb handle and the finger handle may be adjusted to fit the hand of the user. A second disengagement mechanism may be provided which allows the thumb handle and finger handle to be rotated about the axis such that they may be arranged relative to the shaft so that an optimal angle may be established between the shaft and the handles.
The present invention is also directed to an end-effector for the tool handle. The end-effector includes a surgical tool which is capable of a first orientation and a second orientation. In addition, the end-effector includes a camming surface or a cam, said camming surface set for engaging the cam. One of the cam and the camming surface is fixed relative to the shaft of the tool, and the other of the cam and the camming surface is fixed for movement with the rod actuator. The end-effector works such that axial movement of the rod actuator in the shaft causes the surgical tool to move from the first orientation to the second orientation. During this movement, the cam remains within the outer wall of the shaft during the movement.
Accordingly it is an object of the present invention to provide an endoscopic instrument that has handles that adjust to accommodate different hand sizes and different grip styles.
It is a further object of the present invention to provide an endoscopic instrument that has handles that adjust relative to the shaft for use in a variety of different medical procedures.
It is still a further object of the present invention to provide an endoscopic instrument where the operating linkages for the end effectors do not directly contact the patient.
It is still a further object of the present invention to provide an endoscopic instrument that is cleanable, sterilizeable and reusable.
These and other objects, features and advantages of the present invention will become apparent upon reading the following detailed description of the preferred embodiment of the invention, when taken in conjunction with the drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described with reference to the accompanying drawings which illustrate a preferred embodiment of the endoscopic instrument, falling within the scope of the appended claims, and in which:
FIG. 1 is a side view of a reconfigurable endoscopic tool handle in accordance with the present invention.
FIG. 2 is a rear view of the handle of FIG. 1.
FIG. 3 is a cut-away perspective along the lines 3--3 in FIG. 1.
FIG. 4 is a cut-away perspective along the lines 4--4 in FIG. 3.
FIG. 5 is a cut-away perspective along the lines 5--5 in FIG. 3.
FIG. 6 is a cut-away perspective along the lines 6--6 in FIG. 1.
FIG. 7 is a side view of an end-effector embodying the end-effector of the present invention.
FIG. 8 is a top view of the end-effector of FIG. 7, with part of the insert for the shaft removed.
FIG. 9 is a side view of the end-effector of FIG. 7 taken along the line 10--10 in FIG. 8, showing the grasper arm in an open orientation.
FIG. 10 is a side view of the end-effector of claim 9, showing the grasper arm in a closed configuration.
FIG. 11 is a cutaway perspective view of a second embodiment of an end-effector of the present invention, the perspective view showing one of the grasper arms and having a second of the grasper arms removed.
FIG. 12 is the end-effector of FIG. 11, with the grasper arm in the open position and the actuator rod advanced in the shaft.
FIG. 13 is a cutaway perspective view of the end-effector of FIG. 11 taken along the lines 13--13.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawing, in which like reference numerals represent like parts throughout the several views, FIG. 1 depicts a reconfigurable endoscopic tool handle 10 in accordance with the present invention. The tool handle 10 has a central axis A therethrough and includes a removable housing top 12 and a housing bottom 14. A shaft 15 of the tool, onto which surgical tools or end effectors are attached, extends through the handle 10 and out of the distal end. The central axis A extends substantially perpendicular to this shaft 15.
As can best be seen by FIG. 2, the handle 10 includes a left button 16 and a right button 18 at the rear portion of the housing bottom 14. The left button 16 is removed in FIG. 1 so that a splined insert 20 may be seen.
The handle 10 preferably includes a thumb handle 22 for engaging at least the thumb of a user, and a finger handle 24 for engaging at least one of the fingers of the hand of the user. The thumb handle 22 includes a ratchet slide switch 30 which is connected to a ratchet pawl 32. The ratchet pawl 32 engages separate teeth of a ratchet plate 34, as is described in detail below.
The working relationship between the thumb and finger handles 22, 24 and the buttons 16, 18 is best described by reference to FIG. 3. The left button 16 is preferably a hardened plastic and includes a snap-end which is received in a hole in a splined shaft 36. When the left button 16 is in a normal orientation (i.e., not depressed) the splines in this shaft 36 engage both the splines in the insert 20 in the housing bottom 14 and the splines in an insert 38 in the top end of the finger handle 24. The shaft 36 includes a narrowed, smooth surface between the splines and the left button 16, the use of which will be described below. A spring 40 is journaled within and extends out of the right end of the splined shaft 36 to resist movement of the splined shaft 36 and the left button 16 inward in the housing. The other end of the spring 40 is journaled in a cylinder end cap 41.
The right button 18 includes a snap-end, which is received in a hole in the cylinder end cap 41. The cylinder end cap 41 is attached to a splined cylinder 42. The splined cylinder 42 is larger in diameter than and is configured to receive the right end of the splined shaft 36. A spring 44 engages the inner portion of the button 18 for resisting movement of the button 18 and cylinder 42 inward relative the housing.
Moving from the button end of the cylinder 42 toward the right end of the cylinder, the splined portion of the cylinder 42 engages first a rocker arm 50 having splines therein and then a splined insert 52 for the thumb handle 22. The cylinder 42 includes a narrowed, smooth surface between the splines and the button 18, the purpose of which will be described below.
As can best be seen in FIG. 4, the end of the rocker arm 50 includes a camming surface 53 which has the appearance of finger and which is set to engage an actuator rod cradle 54. This cradle 54 includes an inset for receiving an actuator rod 56 from one of many endoscopic instruments. The actuator rod 56 extends through the shaft 15 of the instrument to an end-effector or surgical tool. The shaft 15 extends through the handle 10 and out of the distal end, as is best shown in FIGS. 5 and 1. Also included in the housing top 12 is an electrical jack pin 60 and an electrical contact 62 for use in electro cautery applications.
As is shown in FIG. 6, the shaft 15 includes a one-piece gear and rotation knob 64 fixed for rotation with the shaft. By rotating this knob 64, tile shaft 15 and actuator rod 56 are also rotated. In turn, the end-effector may be rotated to desired orientation. This rotation does not affect the internal mechanism of the housing or its ability to transfer motion to the actuator rod 56, because tile actuator rod 56 is free to rotate within the actuator rod cradle 54. The gear of the knob 64 contacts a spring detent 66 to hold the rod 56 and end effector in place after rotation.
The manner in which operation of the reconfigurable endoscope tool handle 10 works is understood from the above description. In use, a surgeon or any other user opens the housing top 12 of the tool handle 10 and places a selected shaft 15 having an end-effector (not shown) in the tool. The shaft 15 of the tool includes the one-piece gear and rotation knob 64 and is oriented such that it extends out of the distal end of the tool handle 10 and the actuator rod 56 fits into the actuator rod cradle 54.
The housing top 12 is then replaced and the tool handle 10 is now ready for use. The surgeon simply places his or her fingers into the finger handle 24 and his or her thumb into the thumb handle 22. By gripping the thumb handle 22 toward the finger handle 24, the doctor causes a series of events to occur. Because both the splined insert 20 on the housing 14 and the splined insert 38 for the finger handle 24 are located on the splines of the shaft 36, the finger handle 24 remains fixed relative to the housing 14. The thumb handle 22, on the other hand, is located on the splines of the cylinder 42 along with and adjacent to the rocker arm 50. The splined cylinder 42 is not fixed with the housing, but instead is free to rotate about the central axis A of the tool handle 10. Therefore, movement of the thumb handle 22 back and forth relative to the finger handle 24 causes the rocker arm 50 to move back and forth within the housing. As can be appreciated by FIG. 4, this movement of the rocker arm 50 back and forth causes the camming surface 53 to engage the actuator rod cradle 54 to move the cradle in a linear manner back and forth in the housing. This movement results in the actuator rod 56 moving in and out of the shaft 15, allowing the end-effector to change from a first orientation to a second orientation. If the end-effector is of the grasper type, such as known in the industry, such movement may open and close the jaws of the grasper.
The movement of the thumb handle 22 in one direction may be prevented by use of the ratchet slide switch 30. In FIG. 1, the ratchet slide switch 30 is engaged such that the ratchet pawl 32 is inserted between two teeth of the ratchet plate 34. The angle of the ratchet pawl 32 is such that when tile thumb handle 22 is pressed toward the finger handle 24, the ratchet pawl 32 bends slightly and clicks into the space between the next pair of ratchet teeth. However, movement of the thumb handle in the reverse direction is prevented because the angle of the pawl 32 causes the end of the pawl to dig into the set of teeth on the ratchet plate 34 instead of clicking over the teeth.
The use of the ratchet pawl 32 causes movement of the thumb handle 22 towards the finger handle 24 to occur in incremental steps, in between which no pressure need be applied by the user to the handles. The pawl 32 is also useful for locking the position of the thumb handle 22 relative to the finger handle 24. In this manner. The end-effector may be held in the closed position without it being necessary for the surgeon to keep his or her hand on or apply pressure to the thumb handle 22 or finger handle 24. The end-effector and the thumb handle 24 may be released by simply sliding the ratchet slide switch 30 toward the ring for receiving a thumb on the thumb handle. This removes the pawl 32 from the ratchet plate 34 and allows free movement of the thumb handle 22 in either direction.
The thumb handle 22 and the finger handle 24 may be adjusted relative to one another and about the central axis A of the tool handle 10 by use of one or more release mechanisms. These release mechanisms are provided in the embodiment shown in the drawing by the left and right buttons 16, 18 and the internal mechanisms connected to the buttons and displayed in FIG. 3.
Rotation of the finger handle 24 about the central axis A is made possible by simply depressing the left button 16 against the force of tile spring 40 until the splined portion of the shaft 36 extends inward past the housing insert 20. This allows the smooth, outer portion of the splined shaft 36 to be adjacent to the housing insert 20 and keeps the splines of the shaft 36 in contact with the splined insert 38 for the finger handle 24. Because the housing insert 20 is no longer in contact with the splines of the splined shaft 36, the finger handle 24 may be rotated with the shaft 36 about the axis A to a desired orientation. The left button 16 is then released and the spring 40 returns the button 16 back to its original orientation. In the course of this movement, the splines of the shaft 36 are reinserted into the housing insert 20 and the finger handle 24 is locked once more into place relative to the housing.
Likewise, the thumb handle 22 may be rotated about the central axis A by depressing the right button 18 against the spring 44. Depressing the right button 18 causes the spring 44 to compress and the splined cylinder 42 to move toward the left button 16. This movement causes the splined portion of the cylinder 42 to move from underneath the rocker arm 50 so that the smoother, narrower portion of the cylinder extends under the rocker arm. However, the splines of the cylinder 42 remain engaged with the splined insert 52 for the thumb handle 22. The thumb handle 22 and the splined cylinder 42 may then be rotated about the axis A while the rocker arm 50 remains in place.
For purposes of safety, the thumb and finger handles 22, 24 should not be over-rotated or under-rotated relative to one another, or it may be impossible for a surgeon to open or close the end-effector. This may happen one of two ways. The handles 22, 24 may be too far apart for the surgeon to spread them by simply fanning his or her hand open, or the handles may be so close together that they touch and do not allow full range of movement so that the end-effector may be closed. The present inventors have found that most users have an effective range of movement of the handles between approximately 0° to 70°. That is, most users can close the handles so that they touch completely (a 0° gap) or open them to an orientation of 70° from one another (a 70° gap). However, for complete movement of the rocker arm 50 and therefore the actuator rod 56 and the end-effector, there must be 20° of full movement in the handles. This means that the 20° of movement should fall somewhere in the comfortable range of the user, or within the approximately 0° to 70° gap. Therefore, for optimal use of the tool the handles 22, 24 should never be adjusted less than 20° apart (the minimum distance between the handles for a user or 0°, plus the additional 20° needed for full movement) or more than 50° apart (the maximum separation the handles, or 70°, minus the needed movement of 20°). This allows full movement of the handles 22, 24 by a user in either direction after adjustment has been made.
To prevent this over- or under-adjustment of the handles relative to one another, a tab 70 is provided on the inside of the splined cylinder 42, as is shown in FIG. 4. This tab 70 is configured for cooperating with a narrowed portion 72 of the splined shaft 36. The tab 70 and the narrowed portion 72 work together as a stop to prevent rotation of the handles 22, 24 relative one another outside the comfortable range of motion of a hand of the user. As can be appreciated by FIG. 3, as long as the buttons 16, 18 are not depressed, rotation of the splined cylinder 42 is unimpeded by the splined shaft 36. This is because the tab 70 falls short of the right end of the splined shaft 36 when the buttons 16, 18 are at an arrest position. However, if insertion of the left button 16, the right button 18, or both is attempted, that insertion will not be possible unless the tab 70 aligns along one part of the narrowed portion 72 of the splined shaft 36. The area in which the tab 70 may be inserted into the narrow portion 72 represents an allowable range of movement in which the buttons 16, 18 can be inserted and corresponds to the handles being 20° to 50° apart, the significance of which was discussed above. Likewise, while one or both of the buttons 16, 18 is inserted. The tab prevents over-rotation of one of the handles 22, 24 relative to the other. In this manner, the handles 22, 24 are always in a workable position after repositioning of one or both of the handles.
By use of the buttons 16, 18 and the mechanisms attached to them, the finger and thumb handles 24, 22 may be rotated about the central axis A and relative to the tool 10 so that an advantageous angle may be formed between the shaft 15 and the handles. This allows the handles 24, 22 to be used for thoracic, general abdominal, urological, and gynecological surgeries. By pushing both of the buttons 16, 18 in at once, it is possible to move the finger and thumb handles 24, 22 in unison and to place them in a desired orientation. This gives the surgeon a single instrument capable of many orientations of the handles 24, 22 relative to the shaft 15 so that the tool handle 10 could be used for numerous surgical procedures. Moreover, by pressing in one or both of the buttons 16, 18 on the tool 10, the handles 22, 24 may be adjusted relative to one another so that the handles may fit any size hand.
The tool handle 10 may be used with a variety of different end-effectors, including but not limited to needle holders, graspers, disectors, cutters, and scissors. The end-effectors are operated by the movement of the actuator rod 56 within the shaft 15. This relative movement can cause a grasper jaw to open and close, a cutter blade to cut and retract, or a needle holder to grasp or let go of a needle.
The unique design of the tool handle 10 allows it to be universal for all types of end-effectors. The cradle 54 offers a linear motion which can either be back and forth, or forward in one direction and held in that position for as long as needed. The actuator rod 56 is keyed for precise fitting into that cradle 54 and moves along with the cradle. The shaft 15, on the other hand, is fixed to prevent axial movement in and out of the tool. The shaft 15 and rod 56 may be rotated by use of the rotation knob 64 which allows full 360° rotation of the end-effectors for precise alignment of the end-effector, which enables efficient operator control and eliminates awkward wrist movements.
An example of an end-effector 80 which may be used with the tool handle 10 is pictured in FIG. 7. The end-effector 80 is of the grasper variety. The embodiment shown in FIG. 7 provides operating linkages which remain within the outer diameter D of the shaft 15 and therefore the linkages do not contact the patient during rise.
As can be seen by FIG. 7, the distal end of the shaft 15 includes an insert 82 extending the same diameter as the shaft to the end-effector 80. The actuator rod 56 extends through the shaft 15 and the insert 82. A groove 84 in the annular rod is set to receive a U-shaped plate 86. The U-shaped plate 86 extends up the insert 82 such that opposite sides 88, 90 (shown in FIG. 8) of the U-shaped plate face one another. FIG. 8 is a top side view of the end-effector 80 shown in FIG. 7 and has part of the insert 82 removed so that the relation of the plate 86 to the rod 56 and other internal mechanisms may be shown.
The inner surface of each side of the plates 88, 90 include camming surfaces in the form of cam slots 92, 94. A first of the cam slots 92 extends diagonally from a lower, distal portion of the rear plate 88 to a higher, central portion of the plate. The second cam slot 94 extends diagonally from the upper, distal end of the internal portion of the plate 90 to a lower, central portion of the plate. Thus, if it were possible to peer through the insert 82, the two cam slots would seem to cross and form an "x" as is shown in FIG. 7.
The grasper shown in FIG. 7 includes two grasper arms 96, 98. Each of these arms includes a flat, triangular section 100, 102 which partially extends into the insert 82. Cams in the form of pins 104. 106 are included in the ends of the flat, triangular sections 100, 102 for engaging the cam slots 94, 92. A stationary pin 110 extends through each of the grasper arms 96, 98 at the distal end of the insert 82. The stationary pin 110 acts as a fulcrum about which the grasper arms 96, 98 can rotate. Rubber gaskets 112 (only one shown) are included on opposite sides of the two triangular plates 100, 102 to allow free movement of tile grasper arms 96, 98 about the pin 110.
FIGS. 9 and 10 are provided to better describe the operation of the end-effector 80. FIG. 10 is a cross-section along the hatch lines 10--10 of FIG. 8 and for the purposes of clarity has the grasper arm 96 removed. FIG. 9 is the same cross-section as FIG. 10, but has the annular rod 56 advanced in the shaft 15 and the insert 82.
The manner in which the end-effector 80 operates is apparent from the above description and the drawings provided in FIGS. 9 and 10. The grasper arm 98 is shown in the closed position in FIG. 10 with the pin 106 located at the distal end of the cam slot 92 in the position 106A. As the actuator rod 56 is advanced in the shaft 15 and the insert 82, the pin 106 correspondingly advances upward in the cam slot 92. As the actuator rod reaches the end of its advancement, the pin 106 reaches the position 106B and the grasper arm 98 is in the open position. During movement of the actuator rod 56, the pin 106 travels along the path 106C.
As can be understood from the above description, the end-effector 80 utilizes the linear motion of the actuator rod 56 to create first and second orientations of the grasper (closed and opened positions). The movement changes of the end-effector 80 are accomplished without control linkages protruding from the outer diameter D of the shaft. Thus, there are no provisions to catch on tissue or other body parts to cause unwanted damage.
A second end-effector 120 having many of these same characteristics is pictured in FIG. 11. Like the end-effector 80, the end-effector 120 pictured in FIG. 11 is of the grasper variety and is driven by linear, back-and-forth movement of the actuator rod 56 within the shaft 15. A grasper arm 121 is shown in FIG. 11, and a second grasper arm (not pictured) is similarly mounted on the other side of the end-effector 120, as will be understood in the description below. The second grasper arm is removed in FIGS. 11 and 12 to facilitate understanding of the operation of the end-effector 120.
The rod 56 in the embodiment shown in FIG. 11 flattens out at its distal end into a fiat piece 122. As can be seen in FIG. 13, a pin 124 extends through the flat piece 122 and also through two grasper arm extensions 126, 128. This pin serves as a pivot point for the two grasper arms. The grasper arm extension 126 is attached to the grasper arm 121 and the grasper arm extension 128 is attached to the second grasper arm (not pictured). The grasper arm 121 includes a camming surface in the form of cam slot 130 for engaging a cam in the form of it pin 132. As can be seen best by FIG. 13, the pin 132 extends through an extension 134 of the shaft 15, its well as the cam slot 130. A similar pin 136 is located on the other side of the extension 134 for engaging a cam slot in the second grasper arm (not shown).
The manner in which the end-effector 120 works can be appreciated from the above description and the drawings. In FIG. 11, the grasper arm 121 is in the closed position and the actuator rod 56 is in a retracted position. In FIG. 12, the actuator rod 56 has moved forward (or to the left in the drawing) causing the cam slot 130 to move forward and upward as a result of engagement with the pin 132. This forward and upward movement of the cam slot 130 causes a corresponding opening of the grasper arm 121. Retraction of the actuator rod 56 causes the grasper arm 121 to move backward and downward along the pin 132 until the grasper arm is back into the closed position.
As with the end-effector 80, the end-effector 120 utilizes the linear motion of the actuator rod 56 to create first and second orientations of the grasper pieces (closed and opened positions). The movement changes of the end-effector 120 are accomplished without controlling surfaces protruding from the outer diameter D of the shaft, and therefore the end-effectors do not cause damage to outlying tissue and can be easily cleaned, sterilized, and reused.
It should be understood that numerous modifications or alternations may be made to the device without departing from the spirit and scope of the invention as set forth in the appended claims. | The improved endoscopic instrument of the present invention includes handles, a shaft and an end effectors. The handle is capable of adjustment to accommodate variations in hand size, and grip style. The handle is also adjustable relative to the shaft for use in a variety of medical procedures. In addition, the control linkages for the end effector of the improved endoscopic instrument of the present invention do not directly contact the patient thereby enabling the instrument to be easily cleaned, sterilized and reused. | 0 |
[0001] This application is a continuation in part of PCT/IB 2013/000500
SPECIFICATION
Background of the Invention
[0002] Offshore and onshore oil well blowouts are a mayor concern for the oil industry. When they happen, in addition to the losses of lives, the oil spills can bring humongous environmental damages which disturb the normal habitat of many animals as well as the local economies of nearby towns.
[0003] To plug a well that is gushing can take several months. It can be done with the help of drilling a relief well. Capping a well with a device that has not any relief of pressure might compromise the well integrity. Even if the casing is strong enough to hold the pressure at the surface of the well, a fracture at the casing shoe can happen. This fracture can go up to the surface and produce seeps.
[0004] Trying to place a capping device on the well head is not an easy task if the well is gushing with high pressure. The present paper presents a new capping devise that will be easy to install and that can help to minimize the oil/gas pollution and keeps the well integrity. In addition, it teaches how to take control of the well or to plug it. Placing a capping device on the top of an oil/gas well that is under blowout conditions is extremely difficult due to the high pressure of the well which will push away anything that gets closer to the plume. A solution to this problem is to place a detachable capping device that will embrace the well head through the sides, so, the plume will not interfere with the installation of it.
[0005] In previous art, there are some capping devices that are detachable; however, they need a riser or a conductor pipe where they can be attached. The one presented here does not need it. It can be attached to a flange if needed, or it can be clamped in any place of the wellhead. If the capping device is non detachable, the problem is that the fume will push it away and it will be extremely difficult to attach it in the well that is under blowout conditions. Even though the solution is simple, it is not obvious. The proof is there are many companies investigating this problem and none one has come with this approach. After the oil spill in the Gulf of Mexico in year 2010, at least two capping devices have been designed by some major oil companies in conjunction with blowout preventers manufacturing companies. The designs are not detachable and the designs do not present a capping device that will not be disturbed by the fume. So, to the present, the designed capping devices for a well that is under blowout conditions have different problems. If a capping device is detachable, it does not offer any pressure relief, or if it does offer a pressure relief, it may be extremely difficult to cap due to the closing mechanism. In addition, none of the capping devices searched in the literature offer the chance to recover the oil gas/well. The capping device presented here is detachable, shows an easy way to cap the gushing oil/gas well, keeps the well integrity by offering a relief mechanism, and offers a chance to recover the well. It also can be used in offshore and onshore operations. It can connect to the wellhead using standard flange connection, or, using a couple of lower sealing blocks that will fit the external profile of the place where they will be clamped.
[0006] U.S. Pat. No. 1,249,167 by Michigan reveals how to place the base of a capping device alongside the riser. In the absence of a riser or conductor pipe, this method will not work. In addition, even though this method uses split clamps that are attached alongside the riser, the capping (nipple that can have a valve, T, elbow, etc.) device is not split or detachable and at the moment that it can be tried to be screwed on the top of the base, the high pressure from the plume of the well that is gushing will take it aside. So, it will have the same problem that any cap that is already preassembled and is not detachable in two housing members.
[0007] Lite Teed et al. U.S. Pat. No. 1,807,498 discloses a capping device with the top as a T which has pipes going up and to the sides. The pipe that goes up does not get inside of the well. This capping design might be good for collecting oil/gas, but not to plug the well, or try to have some control over the well.
[0008] U.S. Pat. No. 3,820,601 by Walker, Jr. et al. discloses a capping device which need a riser or conductor pipe to be installed. Without it, it will not work. It presents a similar way to be attached to the casing as U.S. Pat. No. 1,249,167. The difference is that this capping device will cut the upper place of the conductor pipe and will replace it with a plate that will seal the upper section. This capping device can compromise the well integrity if the downhole pressure is too high. In addition, it does not present a way to try to lower a service string to kill the well. This device is intended to shut down the well and it does not offer any relief mechanism.
[0009] U.S. Pat. No. 1,786,848 by J. Johnson presents another capping device similar to Walker Jr. et at. In which it is necessary to have a conductor riser or casing in order to installs the device. This one also does not present any relief mechanism and does not allow a string of pipe to kill the well. It also could affect the well integrity.
[0010] U.S. Pat. No. 8,540,031 B2 by Rimi presents a tri-flange system having flanges on the top and sides of the housings. This device is detachable. A problem with this design is that when the top flange which has a lid is going to move to a closed position, the flange and the lid have to pass through the plume encountering it from a line of force parallel to the plume and trying to take it to a line of force with an angle perpendicular to the plume. Trying to do this fit is even much more difficult than coming with a pre-assembled heavy weight capping device from the top of the well (with a force direction directly opposite to the force of the plunge). In addition, this device does not offer any change to try to recover the well.
[0011] U.S. Pat. No. 2,06,252 by William D. Shaffer and at present a new packing system for blowout preventers or control gates for gas and oil well casing. They provide a gate ram and its packing having sealing efficiency against pipe in the hole. This gate facilitates replacement of that part of the packing which is exposed to the grates wear and tear owing to its engagement with the pipe string to be packet in the casing, and provide for such replacement without the need of changing or discarding of that part of the packing which is extruded against a continues part of the ate shell and not subject to abrasive tear to much extend
[0012] U.S. Pat. No. 2,090,206 by W. E. King presents a blowout preventer ram that addresses the problem of centralizing a string of pipe inside of the oil/gas well and make a perfect seal against the string of pipe, so, fluids cannot escape between the outside space of the string of pipe and the casing
[0013] U.S. Pat. No. 3,817,326 by Meyner teaches about a ram type BOP which has a mean to shearing a pipe which may be disposed within its bore and them sealing across the bore.
[0014] Carrascal U.S. Pat. No. 8,215,405 B1 builds a filter in order to restrict the flow of fluids out of the well. After the filter is built, he teaches several options to plug the well such as pumping polymers that expand in contact with oil, or pumping cement. These chunks of polymers do not go out of the well due that the filter about them avoids them to get out of the well. The method proposed in the present paper uses heavy metals embedded in expandable polymers in conjunction with a detachable capping device to try to take control of the well.
[0015] Other patents of interest are:
Application EP 0159813 A3 by Stephen J. Walker
US20080302536 by Glenn J. Chiasson
[0016] U.S. Pat. No. 5,911,284 by Gunther Von Gynz-Rekowski
U.S. Pat. No. 6,527,513 by Kenneth Roderick Stewart at al.
[0017] The present paper discloses a capping device that can be used in conjunction of a string of pipe to stop a well blow out once it is happening in matter of short time. This capping device keeps the well integrity. Depending of the physical conditions of the well, it could be possible to recover the gushing well. In case that it might be too difficult to lower a string of pipe to be run into the well, the capping device can be closed on the top and fluids coming from the well can be conducted to surface through a string of pipe that can be connected at the sides of the capping device, or, if a new riser is connected, the fluids can be redirected to surface using the new riser. If pipe can be run in the gushing well, there is change that the well can be recovered using any know well control method.
SUMMARY OF THE INVENTION
[0018] When an oil/gas well is under blowout conditions, it can be shut down by closing the Blow Out Preventers, BOPs, if they are working. Assuming this is the case, the well integrity can be compromised. In a similar way, if a capping device is placed on the top of the BOPs, and the capping device does not provide a way to relief the pressure from the well, the well integrity might be compromised at the top of the well head where the casing is weaker for burst pressure, or at the casing shoe where a fracture could be induced. This fracture could be extended to the surface creating seeps on the ocean floor making the problem more difficult to solve. Another way that the oil industry has used to kill a well that is under blowout conditions is to drill a lateral well which will intercept the gushing well somewhere down hole. Once the well has been intercepted, the operation to kill the gushing well can be finalized. This method can take several weeks or months. During this time, the environmental pollution might be humongous.
[0019] The present, capping device can be used in conjunction with a string of pipe to take control of the well, or to plug it. If desire to plug the well, a killing string of pipe can be tried to lowered near the bottom of the well and metals, or any material embedded in expandable polymers can be pumped, so, in time, the expandable polymer sensitive to oil, will expand and plug the well. In case that running a string of pipe into the well cannot be possible, the capping device can be closed and the downhole fluids will be directed to surface through pipe, it will provide time for a relief well to be drilled and later plug the well using the relief well.
[0020] The capping device is detachable. In this way, it will be easier to be placed on the wellhead compared with a capping device that is already preassembled. Trying to set a capping device that is already preassembled on the top of the BOPs, or at the base of the casing where the BOPs are attached is extremely difficult due to the force from the plume of the well. Because this capping device is detachable, it will be easier to place it on the wellhead. Rather than trying to set the device from the top of the well, the device can be set from the sides where the plume of the well is not interfering with the installation. The base of the detachable capping device can have a flange that splits or it can have the shape or same profile of the place in the BOPs where it is going to be attached, or it can have the outside shape of the casing or riser and be attached there.
[0021] The capping device can have one or more chambers. It can also have one or more sealing blocks. This paper will show some options for designing the capping device. One option is a capping device which has only one sealing block, or any suitable valve to stop the flow of fluids to the environment. Also, in the first chamber, there are at least a couple of relief holes that are connected with pipe in order to conduct the down-hole fluids to surface. The housing of the capping device can have any geometrical shape such as a cylindrical shape, cuboidal shape, spheroidal shape, or any desired shape. The same applies for the sealing blocks, as a matter of fact; almost any well-known valve can be used to close the flow of fluids to the environment. For example of a closing mechanism is a ball valve which can be full or a split ball. Pretty much many well-known valves in the market can be used to close the well once the detachable capping device is attached to the any place in the BOPs, or in the casing or riser.
[0022] A second chamber can have a couple sealing blocks that may have pipe centralizers which will centralize a string of pipe that will be used to kill, or plug the well. These blocks will seal the space between the casing and the string of pipe that will be used to kill the well. If there is more than one sealing block or valve, the position of which one goes first is dependent of purpose and personal choice. As a matter of fact, if desired, it could be only one chamber with one or many sealing blocks or valves.
[0023] If a killer string cannot be run into the oil/gas well because the water depth is too short, or for any other reason, the second chamber can have a ball, or a cuboid, or a cylinder which can be used to close the capping device at the top, allowing fluids to be redirected to surface through pipe that is connected to the lower relief holes in the housing of the device. The sealing block can be moved using hydraulic cylinders or a threaded rod, or it can be done by any mechanical means. Another way to close the capping device is to use a flip flap valve with a closing mechanism that goes from the bottom to the top, so the downhole fluids will close the valve. Once the flap valve is activated to be moved by the downhole fluids to closed position, it will close violently. If a flap valve with closing mechanism that goes from the top to the bottom is used, it will be extremely difficult to close the valve. Another design could be to clamp the two half housings that have relief holes which are connected to pipe for redirection of fluids to surface on any suitable place in the BOPs and try to put a plug on the top of the capping device.
[0024] For wells that have problems with paraffin some of the energy of the gushing fluids in the oil/gas well can be used with a turbine to generate electricity in order to warm the capping device and avoid plugging of the gushing fluids inside the relief pipes in the capping device, or to generate electricity to operate valves in the capping device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a perspective view of half housing member for a detachable capping device.
[0026] FIG. 2 is a top view of the capping device. Here the two detachable members are together. The moving sealing blocks are in open position.
[0027] FIG. 3 is a perspective view of half housing member from another option for a similar capping device.
[0028] FIG. 4 is a frontal view of half housing of the detachable capping device from FIG. 3
[0029] FIG. 5 is an elevational view of the whole system where the capping device is attached to the BOPs, pipe is run into the oil/gas well and heavy metals which are embedded in expandable polymers are pumped into the well. The produced and pumped fluids are collected in surface by a vessel.
[0030] FIG. 6 is an elevational view of a capping device with three sealing blocks.
DETAILED DESCRIPTION OF THE INVENTION
[0031] In offshore operations when a high pressure oil/gas well is under blowout conditions, thousands of barrels of oil are poured into the ocean or into the lake where the well is gushing, in onshore operations the spill can pollute big areas and go to rivers. Trying to place a capping device on the wellhead is an extreme difficult task. The reason is that the high pressure of the plume will push out any capping device that is already preassembled. In addition, placing a capping device that does not offer any relief of fluids can cause the underground casing to fail or the formation to be fractured bringing as a consequence damaging the well integrity. The capping device can be used in conjunction of drilling pipe to try to take control of the well. Drilling pipe alone cannot do it. If there is not any device to choke the fluids from the well, any pumping of heavy fluids will be doing no too much to bring the well under control. The heavy fluids pumped will be taking up by the oil and gas that are coming from the pay zone. In normal drilling or workover operations when a kick is taken, the well control is done by pumping heavy fluids and choking the well. Usually this can be done because there are still some of the heavy fluids used to control the well still in it. When the well is already gushing at high pressure there is nothing of the original heavy fluids used to control the well on it, in addition, if there was pipe in the well, it could have been taking out by the gushing fluids. To try to take control of the oil/gas well under these new circumstances is extremely difficult. If pipe is in the well, pumping heavy fluids and chocking the well offer the chance to take control of the situation. If it is not possible, as an improvement of the traditional petroleum engineering methods to take control of the well is to try to pump embedding heavy metals into expandable polymers sensitive to oil or water, follow by pumping heavy fluids and choking the oil/gas well. When the well is chucked the free flow of underground fluids is restricted, in this way, if heavy metals that are embedded in expandable polymers sensitive to oil might go down to the bottom of the well. In time, the expandable polymer will expand and plug the bottom of the well. In case that some of these chunks of polymers try to go to back to surface, the string of pipe used to control the well can have in the joint that is nearest to the bottom of the whole a way to restrict them to go up. In this way, the downhole pressure starts to be controlled. So, if heavy fluids are pumped and if the well is being choked, there is a possibility to recover the oil/gas well. When there is not pipe in the hole, the capping device can have the option of lowering pipe into the oil/gas well.
[0032] It is well known in the oil industry that a killer string alone combined with heavy fluids cannot bring the well under control. It is necessary to have some restriction to the free flow of fluids. This paper is presenting a capping device that will allow taking control over the well or it will help to plug it. This should be done in conjunction with a string of pipe, heavy fluids, and choking the well. Perhaps, as a last resource pumping embedded metals in expandable polymers and choking the well.
[0033] FIG. 1 displays half housing member from a detachable capping device which may contain several chambers. Each detachable housing member is similar. The lower chamber 10 has the flange holes that will match the holes of the well head flange or the holes where the riser is attached to the blowout preventer, BOP. Here is where bolts will be placed to secure the housing device to the wellhead. It also contains a relief pipe or hose 20 where the oil/gas coming from the well will be conducted to surface once the moving sealing block 30 is moved to close the scape of downhole fluids to the open water. These sealing blocks are moved by hydraulic cylinders 40 . The hydraulic cylinders 40 are dual action. They can be used to move the sealing blocks to open position or to closed position. A threaded rod can also be used to move the sealing blocks instead of the hydraulic cylinders. The design can also be done where block 30 will not have in the center any profile to fit pipe that may be introduced in the hole. A flat sealing block without any profile can cross from one housing member to the other and seal the well. So, only one block will be used to close the well. In this way there is no need of two blocks to close the well. If desired, the two housing member can be connected with a hinge joint. The upper section of the sealing block 30 may have rollers 90 which will facilitate the moving of the block to open or closed position. A valve 60 can be used to control the flow of fluids. The dosing block 30 may have pipe guide 50 to help to centralize pipe that can be run into the hole. The housing can have an electrical resistance 80 that can be used to warm the capping device in order to avoid the formation of paraffin.
[0034] The sealing block 30 is connected to the pipe adjuster 50 for hermetic seal once both blocks from each half housing member come into contact. The pipe adjuster will guide the pipe that is run into the hole to the center, where they will fit in the center of the sealing block, so, in that way there will be a hermetic dosing between the blocks and the pipe that might be run into the hole to try to control the blowout. So, the underground fluids will not be able to continue escaping to the open water. If pipe cannot be run into the hole, one of the sealing blocks can be moved from one side of the housing member to the other to close the flow of fluids to the outside environment, or, if the device has more sealing blocks located in different positions they can be moved to close the device.
[0035] FIG. 2 shows the two housing members 5 connected. The relief conductor pipe 20 might have a valve 60 . The valve 60 can be used to choke the exit of fluids for well control. A turbine or a motor 70 can also be connected to it. The turbine or motor can also be connected in a separated line to the housing as a second relief of fluids. This should be done in each housing member. The energy from the turbine can be used to open or close the valve 60 that will allow fluids to be conducted to surface. It also can be used to create electrical energy to heat the capping device through an embedded electrical resistance 80 . For deep water wells, the cold temperatures from the bottom of the ocean can make the paraffin from the underground fluids to get solidified making it to plug the conductor pipe of fluids to the surface. So, hydrate plugs can be formed. To avoid the capping device to be plugged, electrical resistances 80 will be embedded in the capping device and in the choking lines. The electrical resistances will warm the capping device and the choking lines. Electricity can be provided by external batteries that the Remote Operated Vehicles, ROVs can take into place or by electricity produced by a motor or a turbine that takes advantages of the mechanical energy produced by the flow of downhole fluids. If a motor or a turbine is connected to the relief pipe, a swivel should be connected at the end, and so, a string of pipe that will conduct the downhole fluids to surface can be connected. The capping device will have external outlets for electricity, so, the electrical resistances can be operated.
[0036] The moving sealing bock 30 have on the top and on the bottom integrated rollers 90 to help it to move in the housing. Another design could be using a moving cylinder rather than a block. Due to the high downhole pressure, once the moving sealing block 30 touches the downhole fluids, they will try to lift it upwards increasing the friction force between the block and the housing. Without the rollers, the friction force between the sealing block and the housing will require high force to close them, or to open them. Therefore, these rollers will facilitate the movement of the sealing block in the housing reducing the amount of force required to move it inside of it. The hydraulic cylinders 40 have a rod 45 and a piston 48 . They are used to move the moving sealing blocks 30 . Another option is to use only one moving sealing block instead of two, which will close the upper chamber making the gushing fluids to be redirected to surface through the relief pipes.
[0037] FIG. 3 is a side view of a capping device. Where 35 is an upper sealing block. This sealing block can be replaced by a ball valve, or a flapper valve, or any suitable valve in the market. The upper flange 15 can be used to connect a new riser. The upper sealing block can be moved by a hydraulic cylinder 48 , or by any mechanical means such a rod. When the upper sealing block is moved to closed position, the fluids that are coming from downhole will exit through a relief hole 20 , which can be connected to a hose or pipe to redirect the fluids to surface. Half housing member 5 is similar to the other half housing member. In this case, the difference is that it contains the upper sealing block.
[0038] FIG. 4 shows half housing of a capping device which uses only one block 35 that goes from one housing to the other to close the flow of fluids to the outside environment. It is another representation from the capping device from FIG. 3 . It can be moved hydraulically or mechanically. A profile 28 can be used to fit the outside side of a BOP, or a casing, or any cylindrical shape where the capping device can be attached. Also, a specific profile can be tailored if need in order to clamp the housing there. There is a relief hole 20 where fluids will be conducted to surface. There is also an option for the device to connect to a flange 15 . The rear wall of the device is where the relief hole can be located. Half housing device 5 contains the basic elements of the detachable capping device. Here it is easy to see the lower chamber 10 .
[0039] FIG. 5 shows how this capping device can be used with conjunction with drilling pipe that is lowered from a drilling ship to try to control the well. The first attempt to control the well should be done by pumping heavy fluids and using any well-known well control method to recover the oil/gas well that is gushing fluids. If this does not work, heavy metals can be embedded in expandable polymers 120 . These polymers will be pumped to the bottom of the oil/gas well. Once they are pumped, the well can be choked. Because the free flow of downhole fluids is restricted, the heavy metals that are embedded in the expandable polymer may fall slowly reaching the bottom of the well. The chunks of expandable polymers can have bigger size than the distance between the outer diameter of the drilling pipe and inner diameter of the casing 140 , so these chunks cannot go up to the wellhead. Another way to stop some of those chunks of polymers to go back to the wellhead will be placing a kind of restrictor like some welding bars in one of the joints of the pipe. After some time, they will expand and seal the bottom. Right after the polymers are pumped, heavy fluids will be pumped continually. By choking the relief lines in the capping device and pumping heavy fluids, it might be possible to take control of the well. In this FIG. 5 the detachable capping device is attached to the BOPS 110 of the well. The produced fluids from the pay zone 130 as well as the pumped fluids from drilling ship will be conducted to surface where a boat will collect them.
[0040] FIG. 6 shows two housing members with lower 37 and upper 32 sealing blocks. The upper sealing block 32 can move from one side of the housing to the other to seal the well using the guide 7 . Under the upper sealing block 32 there are two lower sealing blocks 37 . They have a profile to seal a pipe that may be lowered into the oil/gas well.
[0041] The procedure to try to take control of the well is as follows: The riser will be removed from the top of the BOPs. If the BOPs fell down, they will be removed. Right after this operation is done, the two housing halves of the capping device will be placed on the flange where the riser was attached to the BOPs, or in the flange where the BOPs where attached, or in any suitable place in the BOP stack. Also, the capping device can have the same shape as any part of the BOP and can be attached to them using the mold shape of them. After this, drilling pipe can be run into the oil/gas well. Once the drilled pipe is run into the hole, the sealing blocks of the capping device can be moved to the closed position. When the sealing blocks move to the closed position, the drilling pipe is centralized and a hermetic seal is done. After the hermetic seal is done, downhole fluids will flow in from the lower chamber to the relief pipes of the capping device. These relief pipes will take the downhole fluids to a surface vessel where they will be collected. These relief pipes have choke valves that are used to choke the oil/gas well. After the pipe is run into the well, it can be controlled by circulating heavy fluids and using any well control method used in the oil industry. If after trying to control the well using circulations of heavy fluids and choking the well cannot be done, heavy metals embedded into oil sensitive expandable polymers can be pumped. Afterward, any well control method can be applied again; methods such The Drillers Method (two circulations); The Wait and Weight (Engineers) method (one circulation), The Concurrent Method, heavy fluids will be pumped and the well can be choked. In time, the expandable polymers will expand and seal the bottom of the well. By pumping heavy fluids and choking the well, little by little the well might be controlled, so, the casing pressure will read zero, if it is not possible due to the high pressure, cement should be pumped, and the oil/gas well should continue to be choked until the cement hardens. The string of pipe that is run into the hole can have an obstruction device that will hold any expandable polymers that might try to go to the well head. If nothing works, relief well can be drilled and in this way, the well can be plugged. If the casing has been burst, a caisson should be tried to be placed in the well and the detachable capping device can be place on it.
[0042] Another way to try to control the well is to first move the upper sealing block from the capping device from FIG. 3 to closed position. Fluids will be redirected to surface using the relief pipe connected to the device. After this, a new string of riser can be lowered and attached to the capping device. Later, a killing string of pipe can lowered inside of the riser. The raiser and the string of pipe can be filled with heavy fluids. The upper sealing block from the capping device can be moved to open position; the killing string of pipe can be tried to be lowered to the bottom of the hole. If the killing string of pipe cannot be lowered into the hole due to high pressure, the upper sealing block can be moved to closed position and relief wells can be drilled in order to take control or the well or to plug from below. If the killing siring is lowered, heavy fluids can be pumped through the killing string and choking the well and any well-known method to kill a well can be used, or, the well can be killed by using back circulation with heavy fluids into the well. For back circulation, it is understood that the heavy fluids will be pumped in the space between the inner wall of the riser or casing and outer wall of the killer string and return to the surface from the inner wall of the killing string. | Offshore and onshore oil well blowouts can bring serious environmental damages which can cause serious economic loses. Oil wells under blowout conditions can be gushing fluids for months before the well is capped and plugged. Placing a capping device on the top of the well head can be challenged. In this paper it is presented a detachable capping device and a method that will help to control the well, or to plug it. The gushing fluids will be redirect through pipe to a surface vessel where they will be collected. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control system for a clothes dryer and, more particularly, to a clothes dryer control system incorporating a moisture sensor used to terminate a drying process when the amount of moisture present in the clothes inside the dryer reaches a desired level as selected by a user.
2. Discussion of the Prior Art
It is well known in the art to provide a clothes dryer with a simple time-dry control, in addition to a sensor-dry mode. When the time-dry control is used, the user simply places wet articles inside the dryer and selects the duration for the drying process. Because there is little or no automatic control or adjustment during the process, the drying process simply continues until the time expires. The result can be inefficient, because it is difficult for a user to accurately estimate the time required to reach a desired, final moisture level prior to operating the machine.
In comparison, sensor-dry modes are provided to automatically control a drying operation. Specifically, when a sensor-dry mode is selected, the user places wet articles inside the dryer drum and selects a desired final dryness level. Instead of forcing the user to guess as to how long the process should take, the machine stops when the desired dryness level is reached. For this purpose, the machine includes at least one moisture sensor for detecting the level of moisture of the articles. The machine simply operates until the moisture sensor detects the final desired dryness level selected by the user. By terminating the process upon achieving the desired final dryness level, there is no need to re-start the process to finish incomplete drying. In addition, extra energy is not expended to dry the articles beyond the desired dryness level.
Electronic controls have been developed to assist in the operation of such an automatic drying processes. For example, U.S. Pat. No. 3,762,064, to Offut, discloses a system for automatic operation of a dryer in which extra time is added to a drying process according to a predetermined table. A selection of a dryness level beyond a predetermined level (e.g. damp-dry) results in the addition of extra time. The duration of this extra time is dependent upon the length of time required to reach the predetermined dryness level and the desired final dryness level selected by the user. While this system incorporates a moisture sensor for making a drying operation more efficient, this system is nevertheless highly inefficient, because only one threshold dryness level is detected and the final dryness level is never actually measured, as the time to reach that level is simply estimated. Therefore, just as in time dry modes, the articles will often either be under-dried and still wet, or over-dried.
U.S. Pat. No. 4,477,892, to Cotton, represents an improvement over the system disclosed in the '064 patent and includes sensors or electrodes which contact the wet articles to determine the current moisture level contained therein. Through the system of this patent, the current moisture level inside the machine can be measured at a variety of continuous levels. By comparing the number of conductive electrode “hits” during a given time period, it is possible to estimate the current degree of dryness.
However, there still remains a concern regarding the programming of the operation controller. U.S. Pat. No. 6,020,698 to Stenger et al. discloses the use of multiple binary switches to program an electromechanical timer and an electronic control circuit. A plurality of timer switches are included in relation to a control knob to provide control input, and changing from one control position to an adjacent control position results in a switch either being opened or closed. However, this system only allows a small number of different settings to the microprocessor or electronic control circuit, dependent upon the number of timer switches. Increasing the variability, therefore, requires increasing the number of timer switches and, accordingly, greatly increasing the cost.
Based on the above, there exists a need in the art to provide a control system for a clothes dryer which allows for programming of a wide range of final desired dryness levels, while efficiently drying the clothes contained therein, in a cost efficient manner. Additionally, there exists a need for a clothes dryer which quickly recognizes a dry condition upon commencing a drying cycle and powers down without running a heater.
SUMMARY OF THE INVENTION
The present invention is particularly directed to a control system for a clothes dryer including a timer used to calculate an initial position of a dial or control knob. For instance, during operation of the control system of the invention, the user can select a sensor-dry mode by rotating the dial to a position indicating the final desired dryness level of the articles contained within the dryer. Upon pressing a start button, an internal motor quickly rotates the dial to a preset position, and the time to do so is measured. Because the control system of the invention is programmed with the speed at which the dial is rotated, the initial position of the knob can be quickly and easily determined by multiplying the rotational speed by the time required to rotate the knob. The result is compared to the output from a typical moisture sensor, and drying operation is halted when the detected moisture level reaches the selected level.
Preferably, the control system, via the motor, is capable of driving the dial at different speeds. The first, or fast speed, is used during the initial programming procedure, as described above. A second, or slower speed, is used during the remainder of the sense dry cycle. By providing these varying rotational speeds, greater control and variability is permitted.
Additional objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment thereof, when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a clothes dryer incorporating a dryness level detection and display system according to the invention;
FIG. 2 is a front view of a control panel provided on the clothes dryer of FIG. 1; and
FIG. 3 is a diagrammatic representation of a typical control sequence of a sensor dry mode according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A clothes dryer 1 of the current invention is shown in FIG. 1 and generally includes an outer cabinet 10 , having an opening leading to a rotatable drum 14 and a door 18 for closing the opening. Disposed on the upper surface of the outer cabinet is a control panel 22 for establishing a desired operational sequence for programming the clothes dryer 1 of the invention.
FIG. 2 depicts a close-up view of control panel 22 and includes a plurality of buttons and other elements for controlling clothes dryer 1 . Although control panel 22 is described below in a specific arrangement, it should be understood that the particular arrangement is only exemplary, as a wide range of layouts would suffice. Accordingly, disposed on the left side of control panel 22 is a temperature selector 40 , which includes buttons for determining the heat output of the clothes dryer 1 . In the most preferred embodiment, temperature selector 40 includes an air fluff button 42 , a delicate button 44 , a medium button 46 and a regular button 48 .
Next to temperature selector 40 is a moisture monitor 55 for displaying the current moisture state of articles contained within clothes dryer 1 . Moisture monitor 55 is shown as including a set of LEDs 58 for indicating the specific moisture level. Because the LEDs 58 are vertically arranged, individual LEDs 58 a-f can be illuminated to indicate a current moisture level. For example, a low moisture level can be signified by illuminating only LED 58 a , while a higher moisture level can be shown by illuminating LED 58 d alone or LEDs 58 a , 58 b , 58 c and 58 d simultaneously.
Proximate to moisture monitor 55 is a signal controller 62 . Signal controller 62 is provided to selectively regulate the operation of a buzzer (not shown), and includes an OFF button 64 and an ON button 66 . The selection of ON button 66 causes the buzzer to sound upon completion of the drying operation, while selection of OFF button 64 prevents the buzzer from sounding upon completion of the drying operation. Additionally, control panel 22 includes a start button 70 for commencing operation of clothes dryer 1 .
Finally, control panel 22 includes a control dial 100 for programming clothes dryer 1 . Disposed on the periphery of the center surface of dial 100 is a location pointer 101 which indicates an established setting for dial 100 . Annularly disposed about the periphery of dial 100 is indicia 103 which illustrates the various settings. Specifically, indicia 103 includes a first sense dry zone 105 , a second sense dry zone 110 and a time-dry zone 113 , each defining a portion of indicia 103 and designed to indicate the mode of dryer operation, i.e. a sense dry mode, or a time dry mode. Sense dry zones 105 and 110 each include a MORE DRY setting 120 a , 120 b and a LESS DRY setting 125 a , 125 b with continuous levels therebetween. First sense dry zone 105 also includes a press care setting 128 . Each zone 103 , 105 and 113 includes a cool down sequence at the end of the desired cycle, although not specifically labeled in each zone 103 , 105 and 113 . A plurality of time increments 130 are defined by indicia 103 in time-dry zone 113 . Finally, disposed between each of zones 105 , 110 and 113 are OFF positions 132 a-c . Depending upon the operational state of clothes dryer 1 , dial 100 , and hence location pointer 101 , will reference the appropriate indicia 103 .
With reference to FIG. 1, clothes dryer 1 also includes a control circuit generally indicated at 200 . Specifically a CPU 210 is provided with a timer 215 , and a dryness level determination circuit 220 . A motor 225 is provided to drive timer 215 upon direction from CPU 210 . A moisture sensor 230 is provided as an additional input to CPU 210 . Moisture sensor 230 may be any conventional moisture sensor known in the art, such as the moisture sensor described in U.S. Pat. No. 4,477,982, to Cotton, which is hereby incorporated in its entirety by reference. A series of drum and heater controls are collectively represented at 240 which, when directed by CPU 210 through timer 215 , operate a drum rotation motor (not shown) and a heating element (not shown) in response to a drying profile set by the elements on control panel 22 and the output from CPU 210 .
After wet articles are placed within drum 14 , a user selects an operation in a generally conventional manner. First, temperature selector 42 is used to chose a desired operating temperature for clothes dryer 1 . While selection regular button 48 uses the highest temperature setting and results in the fastest drying time, the “regular” setting may be too hot for some articles. Therefore, additional temperature levels are provided. Before pressing start button 70 and beginning operation of clothes dryer 1 , the user rotates dial 100 from OFF setting 132 into time-dry zone 113 , first sense dry zone 105 or second sense dry zone 110 .
If dial 100 is rotated such that location pointer 101 is in time-dry zone 113 , clothes dryer 1 is in time-dry mode, and simply operates until the time indicated by time increment 130 expires. CPU 210 directs motor 225 to rotate dial 100 at a relatively slow speed through a reduced duty cycle coinciding to time increments 130 , and operates the heater at the temperature chosen via temperature selector 42 . Rotation of drum 14 continues until location pointer 101 reaches OFF setting 132 c. If desired, moisture sensor 230 could be designed to operate during the time-dry mode to display to the user the current moisture level via moisture monitor 55 , even though the sense dry mode was not selected.
The present invention is particularly directed to the operation of clothes dryer 1 in one of sense dry zones 105 or 110 . Second sense dry zone 110 is provided for automatic operation of clothes dryer 1 in most situations. However, first sense dry zone 105 is generally provided for use with permanent press articles or when the user wants wrinkles prevented. The two sense dry zones 105 and 110 operate in substantially the same manner, as commonly known in the art, with their differences not forming part of the present invention. First sense dry zone 105 directs a “wrinkle-free” cycle and therefore, includes press care setting 128 and operates at a lower temperature with an extended period of no added heat, i.e. an air fluff mode, than the cycle directed by second sense dry zone 110 so as to extend tumbling to limit creasing of articles. Because operation of clothes dryer 1 is substantially the same for first sense dry zone 105 and second sense dry zone 110 in accordance with the invention, only one description follows, making specific reference to first sense dry zone 105 .
With reference to the drawings and particularly FIG. 3, just as when time-dry zone 113 is used, when a sense dry mode of clothes dryer 1 is called for, the user places the wet articles inside drum 14 , chooses a drying temperature with temperature selector 40 (Step 300 ), selects signal ON or OFF ( 302 ), and indicates the desired, final dryness level by rotating dial 100 until location pointer 101 points to the desired level (Step 304 ). Specifically, the desired setting may be either MORE DRY setting 120 , LESS DRY setting 125 or somewhere between. After start button 70 is pressed (Step 306 ), CPU 210 through timer 215 begins tumbling of drum 14 (Step 308 ).
In a preferred embodiment, CPU 210 measures the current moisture level within drum 14 via moisture sensor 230 upon commencing tumbling of drum 14 (Step 310 ). Timer 215 is then activated by CPU 210 (Step 316 ) to rotate dial 100 to determine its position or setting (Step 318 ). Specifically, dial 100 is rotated at a relatively fast rate, e.g. 8°/minute, as opposed to the slower speed of 2°/minute. Although in a preferred embodiment, dial 100 rotates at the same speed internally and externally, it is contemplated to rotate dial 100 at the slower speed externally, while moving four times as fast internally, as to maintain a substantially constant rotation as viewed by the user. More specifically, timer 215 rotates dial 100 at a constant known rate from its initial position to LESS DRY setting 125 (Step 320 ). Because the rotational velocity is known, CPU 210 calculates the arc length traveled by dial 100 during this period. By multiplying the preset rotational velocity by the rotation duration of timer 215 , the arc length traversed can be calculated (Step 324 ). For example, if dial 100 is set in close proximity to LESS DRY setting 125 , the rotation period will be substantially less than if dial 100 were set closer to MORE DRY setting 120 . CPU 210 converts this distance value into a dryness level, to be compared to the result from moisture sensor 230 by dryness level determination circuit 220 . At Step 328 , timer 215 is stopped, which halts rotation of dial 100 until later in the cycle.
As indicated above, motor 225 rotates dial 100 at a different rate when in a sensor-dry zone 105 or 110 as compared to time-dry zone 113 . This allows for a greater degree of selection and flexibility in the layout of indicia 103 in the sensor dry zones 105 and 110 . By advancing dial 100 at a faster rate, in effect, more gradations are possible in the sensor-dry zone. In a preferred embodiment, motor 225 rotates dial 100 at a rate of 8° per minute when in sensor-dry zone 105 or 110 and advances dial 100 at a rate of 2° per minute when in time dry zone 113 . Preferably, this is accomplished by advancing dial 100 for 15 seconds out of every 60 seconds.
The heater is then energized (Step 330 ) and clothes dryer 1 operates with dial 100 in LESS DRY selection 125 until the final dryness level is reached (Step 332 ). By continually monitoring the output from moisture sensor 230 , and comparing the output to the desired, final dryness level, dryness level determination circuit 220 causes CPU 210 to advance to the next step when the final dryness level is reached. Essentially, the rotational movement of dial 100 is halted until the desired dryness level is achieved by cycling between Steps 328 - 332 . When the final desired dryness level is achieved, CPU 210 , through timer 215 , restarts timer 215 at the slower speed (Step 333 ), and de-energizes the heater, but permits the continuation of tumbling of drum 14 (Step 334 ). Once the heater is de-energized, clothes dryer 1 enters cool-down mode (Step 338 ).
If ON button 66 of signal controller 62 is depressed (Step 340 ), CPU 210 sounds the buzzer or other notification device to alert the user of the completion of the drying cycle (Step 342 ). If, however, OFF button 64 is depressed, CPU 210 does not actuate the buzzer and proceeds to the next step. Finally, CPU 210 and drum and heater controls 240 stop tumbling of drum 14 and shuts down clothes dryer 1 (Step 344 ).
The particular arrangement of CPU 210 within dryer 1 is designed to prevent excessive heating of articles contained in drum 14 if a dry condition is realized at the initiation of a drying cycle. If dyer 1 is started with an already dry load (or no load at all) therein, this will be detected by moisture sensor 230 in Step 310 . Because this reading will be below any desired dryness level calculated in Step 324 , when CPU 210 progresses to Step 332 , CPU 210 will quickly move through Steps 330 - 334 and almost immediately stop the heater. Therefore, in the event that an already dry load is placed within drum 14 , the heater will only remain energized for a short duration.
With this arrangement, the actual operator established setting between MORE DRY and LESS DRY in either of sense dry zone 105 or 110 is determined by CPU 210 well in advance of reaching a LESS DRY status for the clothes. Although not shown, CPU 210 could be used to control a visual numeric or other type of read-out (not shown) provided on control panel 22 or elsewhere, to indicate to the user the amount of time to an end of cycle. Therefore, although described with reference to preferred embodiments, it should readily understood that various changes and/or modifications could be made to the invention without departing from the spirit thereof. For example, selection element 100 need not be a dial, as one of ordinary skill in the art would recognize that using a slidable element would be within the scope of this invention. Additionally, indicia 103 may include a variety of additional dryer cycles, or simply a single sense dry zone. In any event, the invention is only intended to be limited by the scope of the following claims. | A method of programming and controlling an automatic cycle of a clothes dryer provides that, after positioning of a selection dial, a motor associated with the selection dial is rapidly moved to a predetermined location at a constant speed, while the time to do so is measured. With the rotational velocity being known, the exact, initially setting position of the dial is determined in advance. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to Taiwan application 100148453, filed on Dec. 23, 2011, the content of which is incorporated by reference.
TECHNICAL FIELD
[0002] The disclosure relates to production of graphene.
BACKGROUND
[0003] A graphene sheet is composed of carbon atoms occupying a two-dimensional hexagonal lattice. Graphene can have a high carrier mobility and excellent thermal conductivity. Graphene can be used in, e.g., semiconductor devices, touch panels, and solar cells. Graphene can be fabricated by, e.g., mechanical exfoliation, epitaxial growth, chemical vapor deposition, and chemical exfoliation. Methods for producing graphene have been described in U.S. Pat. No. 7,790,285, U.S. Pat. No. 7,892,514, and U.S. patent application Ser. No. 13/170,624, filed on Jun. 28, 2011.
SUMMARY
[0004] In one aspect, an apparatus is provided for preparing high-quality graphene and graphene oxide in a simple and fast manner at a low cost. The graphene and graphene oxide can be produced by electrochemical exfoliation.
[0005] In one aspect, an apparatus for producing graphene and/or graphene oxide is provided. The apparatus includes a first electrode that includes graphite; a second electrode; a container that contains an electrolyte, in which the first and second electrodes are immersed in the electrolyte; a power supply to supply bias voltages across the first and second electrodes to cause intercalation of graphite and exfoliation of graphene; and a filtration module to separate the graphene from un-exfoliated graphite particles and collect the graphene.
[0006] In one aspect, a method for producing graphene and/or graphene oxide includes immersing a first electrode and a second electrode in an electrolyte, the first electrode including graphite; applying a first voltage across the first and second electrodes to cause intercalation of the graphite to form a graphite intercalation compound; applying a second voltage across the first and second electrodes to exfoliate the graphite intercalation compound to produce at least one of graphene or graphene oxide; filtering the electrolyte using a first filter that blocks un-exfoliated graphite particles and allows the at least one of graphene or graphene oxide to pass through; and filtering the electrolyte using a second filter to collect the at least one of graphene or graphene oxide.
[0007] In one aspect, an apparatus for producing graphene and graphene oxide includes a first electrode that has an electrode holder having a starting graphite material, a second electrode, an electrobath, a power supply, and a module for filtering and separating the graphene products.
[0008] Implementations of the apparatus can include one or more of the following features. The first electrode can be an electrode holder that includes the starting graphite material, and the second electrode can be either an electrode holder that includes the starting graphite material or a metal. The starting graphite material can include a mixture of graphite and metal. To electrochemically exfoliate graphene, the first electrode and the second electrode can be placed in an electrolyte. Intercalation of the graphite material is performed using a first bias voltage, and the exfoliation of the graphite material is performed using a second bias voltage. The solid graphene products are taken out of the electrolyte. The final graphene product is not necessarily limited to being dissolved in the electrolyte. In some examples, the final graphene product can also be collected in an electrode holder.
[0009] The starting graphite material can include natural graphite in a layered structure, artificial graphite, composite material prepared from graphite powder, or a combination of the above. The starting graphite material can include natural graphite, highly-oriented pyrolytic graphite (HOPG), pitch-based graphite, resin-based graphite, PAN-based carbon fibers, pitch-based carbon fibers, coal, a carbon material containing graphite layers, and/or a carbon material containing graphite flakes. The starting graphite material can be a crystalline graphite layer material in the form of large particles, fragments, or powder, or having an irregular shape. The starting graphite material can also be a block of graphite material made of pieces having the forms described above and held together by an electrically conductive adhesive.
[0010] To increase the efficiency of mass production of graphene, each of the two electrodes can include two or more sub-electrodes connected in parallel or in an array. Each sub-electrode can include a starting graphite material or an electrode holder that includes the starting graphite material.
[0011] The metal in the second electrode can be a precious metal that is resistant to acid and alkaline, such as platinum (Pt), silver (Ag), gold (Au), iridium (Ir), osmium (Os), palladium (Pd), rhodium (Rh) or ruthenium (Ru). Other electrically conducting material that is resistant to chemical etching, such as copper (Cu), stainless steel, graphite, glassy carbon, or conducting polymer, can also be used in the second electrode.
[0012] The electrolyte can be placed in a container made from glass, polymer material (e.g., acrylic, polypropylene, polystyrene, or polyvinyl chloride), stainless steel, or another metal material. The electrolyte can include hydrogen bromide, hydrochloric acid, or sulfuric acid. Alkaline such as potassium hydroxide or sodium hydroxide can be added to the electrolyte. The electrolyte can include an oxidant, which can include potassium bichromate, permanganic acid or potassium permanganate.
[0013] To enhance the graphene or graphene oxide production efficiency and to enhance the graphene product quality, the electrolysis process may be supplemented with heating, application of ultrasound or microwave, application of high-energy light radiation, and/or stirring the electrolyte by a rotor as needed to facilitate exfoliating of graphene or graphene oxide.
[0014] To implement a continuous production process, the exfoliated products can be fed into a module for filtering and separating the graphene products. The first component of the module is a microporous sieve having a size of about 18 mesh to 1250 mesh, preferably from 35 mesh to 500 mesh, for filtering large graphite particles that have not been exfoliated. The microporous sieve allows products having the desired sizes to pass through. The second component of the module is a filtration membrane that collects the graphene sheet product that passed through the sieve. The membrane can have a pore diameter of about 200 nm to 10 μm, preferably from about 500 nm to 5 μm. The graphene product collected from the filtration membrane can be treated with deionized water or other ionic solutions (such as hydrochloric acid) capable of dissolving or replacing the residual ions (such as potassium ion or sulfite ion) to remove the residual electrolyte.
[0015] The bias voltage can be provided by a direct current (DC) or alternating current (AC) power supply. The power supply can be controlled in a constant voltage mode or a constant current mode. In the examples below, the power supply operates in a constant voltage mode to provide controlled bias voltages. The first bias voltage can range from 0.5 V to 10 V, preferably from 2.5 V to 5 V. The second bias voltage can range from 5 V to 220 V, preferably from 10 V to 100 V.
[0016] In one aspect, a method is provided for mass production of graphene and graphene oxide by using the apparatus described above that uses electrochemical exfoliation in which intercalation and exfoliation of graphite material is performed at room temperature through changing voltage without applying high temperature for reduction. The process is simplified and a large amount of highly graphitized graphene with a few layers and large lateral dimensions can be prepared within a short period of time.
[0017] In one aspect, a method is provided for mass production of graphene and graphene oxide. The method includes placing the first electrode and the second electrode in an electrolyte, in which the first electrode is an electrode holder that includes a starting graphite material, and the second electrode is an electrode holder that includes a starting graphite material or a metal. The starting graphite material can include a mixture of graphite and metal. The intercalation of the starting graphite material is performed under a first bias voltage, and the exfoliation of the starting graphite material is performed under a second bias voltage. The exfoliated products are fed into a module for filtering and separating the products. The module includes a first component, which can be a microporous sieve, and a second component, which can be a filtration membrane. The graphene product and/or graphene oxide are collected from the filtration membrane.
[0018] Implementations of the method can include one or more of the following features. The first electrode and the second electrode can be used as the anode and the cathode, respectively, and can be wrapped with an electrode wire and immersed in an electrolyte. The graphite material can be subject to the intercalation step under the first bias voltage in which the anions in the electrolyte, such as sulfate ions and nitrate ions, are intercalated into the interlayer space between two adjacent graphite layers or their grain boundary due to the electric field produced by the bias voltage. The first bias voltage can range from 0.5 V to 10 V, preferably from 2.5 V to 5 V, and the reaction time can range from about 1 minute to 30 minutes, preferably from 1 minute to 5 minutes.
[0019] Subsequently, the graphite material is subject to the exfoliation step using the second bias voltage, in which the second bias voltage is greater than the first bias voltage and can range from 5 V to 220 V, preferably from 10 V to 100 V, and there is no restriction on the reaction time.
[0020] The method can further include performing the exfoliation step for the graphite material using a third bias voltage that is different from the second bias voltage. For example, the third bias voltage and the second bias voltage may have opposite polarities or have the same polarity but different values, in which the second bias voltage and the third bias voltage may be direct current and alternating current, respectively. If the third bias voltage and the second bias voltage have opposite polarities, then the positive voltage can facilitate exfoliating and oxidizing the graphene and subsequently the negative voltage can reduce the oxidized graphene. For example, the second bias voltage can be 10 V and the third bias voltage can be −10 V, in which the reaction time is 2 seconds and 5 seconds, respectively, and the two voltages are alternatively applied for a certain period of time. The intercalation step and the exfoliation step can be performed by switching between different first and second bias voltages, depending on the composition and acidity of the electrolyte to achieve the optimal quality and yield.
[0021] In some implementations, a first bias voltage (e.g., 0.5V) can be applied to the electrodes for a period of time to cause intercalation, and a second bias voltage (e.g., 5V) can be applied to the electrodes to cause exfoliation. In some implementations, during the exfoliation step, a second bias voltage (e.g., 5V) and a third bias voltage (e.g., −5V) are alternately applied to the electrodes, each of the second and third bias voltages being applied for a certain period of time (e.g., 2 seconds). The graphene obtained using the second method of alternating between the second and third bias voltages may have a higher quality, compared to using only the second bias voltage.
[0022] The bias voltage can be selected based on a desired production rate and quality of products. For example, when the absolute value of the bias voltage is higher, the exfoliation rate may be faster but the quality of the produced graphene may be lower. When the absolute value of the bias voltage is lower, the exfoliation rate is slower but the graphene quality may be better.
[0023] After the exfoliation step, the exfoliated products may be provided to a module for filtering and separating the products. The first component of the module is a microporous sieve (e.g., 35 mesh) for filtering un-exfoliated large graphite particles and obtaining the products in suitable sizes that pass through the sieve. The second component of the module is a filtration membrane having a pore diameter of, e.g., 400 nm for collecting the graphene sheet product passing through the sieve. The graphene product and graphene oxide collected from the second component can be treated with a large amount of deionized water to remove the residual electrolyte, or be treated with other ionic solutions (such as hydrochloric acid) capable of dissolving or replacing the residual ion (such as potassium ion or sulfite ion) to remove the residual electrolyte. The module mainly relies on an air pump to accelerate the filtration process. In some examples, filtration and separation can be achieved by vacuum filtration.
[0024] Advantages of the aspects, systems, and methods may include one or more of the following. High quality graphene and graphene oxide can be produced in mass quantities. The cost for producing the graphene and graphene oxide is low. During the production process, it is not necessary to subject the graphene or graphene oxide to a high temperature.
BRIEF DESCRIPTION OF DRAWINGS
[0025] FIG. 1 is a diagram of an apparatus for producing graphene and graphene oxide.
[0026] FIG. 2 is a diagram of an exemplary electrode holder that includes starting graphite material.
[0027] FIG. 3 is a photo showing graphene dispersed in 250 mL of DMF.
[0028] FIG. 4 is a photo showing solid graphene after separation and filtration.
[0029] FIG. 5 is a scanning electron microscope image of exemplary solid graphene powder.
[0030] FIG. 6A is an image of an exemplary graphene sheet.
[0031] FIG. 6B is a graph showing exemplary measurements by an atomic force microscope of a portion of the graphene sheet shown in FIG. 6A .
[0032] FIG. 7 is a graph shows data obtained from a confocal Raman microscopic system for analyzing the bonding of graphene sheets.
[0033] FIG. 8 is a graph showing the characteristic Raman peaks of graphene oxide.
[0034] FIG. 9 is a diagram of an apparatus for producing graphene and graphene oxide.
[0035] FIG. 10 is a flowchart of an exemplary procedure for producing graphene.
DETAILED DESCRIPTION
[0036] Graphene sheets can be mass produced by a process that includes intercalation, exfoliation, and filtration. The intercalation and exfoliation are performed in an electrolyte. Graphene and graphene oxide are separated from un-exfoliated graphite particles by a filter having a mesh size selected to block the un-exfoliated graphite particles and allow the graphene and graphene oxide to pass. The graphene and graphene oxide are collected by a filtration membrane having a pore size smaller than the sizes of the graphene and graphene oxide to be collected.
[0037] Referring to FIG. 1 , an exemplary graphene production system 100 includes a first electrode 102 and a second electrode 104 . In this example, the first electrode 102 is an anode and the second electrode 104 is a cathode. Each of the electrodes 102 and 104 is wrapped with an electrode wire (not shown) and immersed in an electrolyte 106 . The first electrode 102 can be made of a starting graphite material or include a holder that contains starting graphite material. The second electrode 104 can be made of a starting graphite material or metal, or include a holder that contains a starting graphite material. For example, the starting graphite material can include highly-oriented pyrolytic graphite (HOPG), pitch-based graphite, resin-based graphite, polyacrylonitrile-based carbon fibers, pitch-based carbon fibers, or coal. The metal used for the second electrode 104 can be a precious metal that is resistant to chemical etching, such as platinum, silver, gold, iridium, osmium, palladium, rhodium, or ruthenium. The second electrode 104 can also be made of other conducting materials, e.g., copper, stainless steel, glassy carbon, or conducting polymer.
[0038] The graphene production system 100 can also be used to produce graphene oxides.
[0039] Each of the first electrode 102 and the second electrode 104 can be made of crystalline graphite layer material in the form of large particles, flakes, or powder, or having an irregular shape. The electrodes can also be a bulk material composed of graphite particles, flakes, or powder bonded together by an electrically conductive adhesive. In some implementations, to increase throughput in mass production, an electrode can include two or more sub-electrodes connected in parallel or in an array.
[0040] In some implementations, the electrolyte 106 can be placed in a container 108 made from glass, polymer material (e.g., acrylic, polypropylene, polystyrene, or polyvinyl chloride), stainless steel, or other metals. The electrolyte can include hydrogen bromide, hydrochloric acid, or sulfuric acid. Potassium hydroxide can be added to the electrolyte. The electrolyte can include an oxidant, such as potassium bichromate, permanganic acid or potassium permanganate.
[0041] A voltage supply 114 provides a bias voltage to the first and second electrodes 102 and 104 . The voltage supply 114 can supply a direct-current (DC) or alternating-current (AC) bias voltage. When a first bias voltage (e.g., in a range from 0.5 V to 10 V) is applied to the first and second electrodes 102 and 104 , ions in the electrolyte 106 can penetrate spaces between layers in the starting graphite material to form a graphite intercalation compound. This is referred to as the intercalation step. When a second bias voltage (e.g., in a range from 5 V to 220 V) is applied to the first and second electrodes 102 and 104 , the graphite intercalation compound is exfoliated to form graphene sheets that are dispersed in the electrolyte 106 .
[0042] The graphene sheets are can be removed from the electrolyte using a filtration process. A pump 118 pumps the electrolyte 106 , which contains the graphene sheets, to the filtration module 116 . The filtration module 116 includes a microporous sieve 120 and a filtration membrane 122 . The microporous sieve 120 filters out un-exfoliated large graphite particles and allows graphene sheets of suitable sizes to pass. For example, the microporous sieve 120 can have a size in a range from 18 mesh to 1250 mesh, preferably 35 mesh. The size of the sieve can be selected depending on the size of the exfoliated products. The filtration membrane 122 collects the graphene sheets that passed through the sieve 118 . The filtration membrane 122 can have a pore diameter in a range from 200 nm to 1,200 nm, preferably 400 nm. The size of the pore diameter can be selected depending on the size of the exfoliated products. The graphene sheets collected at the filtration membrane 122 can be washed with a large amount of deionized water to remove the residual electrolyte. The graphene sheets can also be washed by using other ionic solutions (such as hydrochloric acid) capable of dissolving or replacing the residual ion (such as potassium ion or sulfite ion) to remove the residual electrolyte. In some examples, the pump 118 is stopped periodically, the filtration membrane 122 is removed from the filtration module 116 and rinsed. The graphene is removed from the filtration membrane 122 . An air pump 124 provides an additional suction force to accelerate the filtration process. The electrolyte can be recycled after being filtered by the filtration module 116 .
[0043] The efficiency of exfoliation can be enhanced by heating the electrolyte 106 using a temperature controller 112 and/or stirring the electrolyte 106 using a rotor 110 . The efficiency of exfoliation can also be enhanced by applying ultrasound microwave to the electrolyte 106 and/or irradiating the electrolyte 106 with high-energy light.
[0044] If the starting graphite material is in a block form having an edge length of, e.g., 1 centimeter or more, the starting graphite material may be directly connected to the voltage supply 114 and be used as an electrode. Referring to FIG. 2 , if the starting graphite material is fragmented or in powder form, an electrode holder 140 can be used as part of the first electrode 102 and/or the second electrode 104 . The electrode holder 140 includes a separation sieve 142 that holds a starting graphite material 144 , which may be crystalline graphite layer material that is fragmented or in powder form, or other formats that prevent direct connection to the voltage supply 114 . The separation sieve 142 can be made of, e.g., a filter sieve (e.g., having a pore size in a range from 0.1 mm to 5 mm), a porous membrane, or a component with pores.
[0045] The separation sieve 142 can have one or more of the following functions. The separation sieve 142 can allow dispersed starting graphite material to maintain a compact and conducting state and be electrically connected to the voltage supply 114 . The separation sieve 142 can allow the starting graphite material to access the electrolyte 106 to effect electrochemical exfoliation. The separation sieve 142 can allow exfoliated graphene sheets to diffuse into the electrolyte 106 so that remaining unreacted starting graphite material can continue to react with the electrolyte. The separation sieve 142 can have a pore size that is related to the dimensions of the starting graphite material and should be configured to prevent the unreacted starting graphite material from passing through.
[0046] In some examples, the separation sieve 142 can have a pore size selected to be sufficiently small to trap the produced graphene sheets inside the separation sieve 142 . This way, the graphene sheets can be collected in the electrode holder 140 .
[0047] The separation sieve 142 can be made of an electrically insulating material that is resistant to acid and alkaline. For example, the separation sieve 142 can be made of glass, acrylic, polypropylene, polystyrene, polyvinyl chloride, other polymer materials, or metal materials that have been processed by insulation and anti-corrosion treatments. A metal electrode 146 electrically connects the starting graphite material to an external circuit that is electrically connected to the voltage supply 114 . The metal electrode 146 applies a fixed pressure to the starting graphite material 144 so that the graphite fragments or powder are coupled more closely together to improve better conductance.
[0048] FIG. 3 is a photo 150 of a solution obtained using the graphene production system 100 ( FIG. 1 ). The solution includes graphene sheets that are dispersed in 250 mL of dimethylformamide (DMF). The solution is sometimes referred to as a “graphene ink” and can be used to produce graphene thin films.
[0049] FIG. 4 is a photo 160 showing solid graphene powder obtained using the graphene production system 100 .
[0050] The graphene sheets were observed by using a scanning electron microscope (SEM), model JEOL-6330F, and an atomic force microscope (AFM), Veeco Dimension-Icon system. FIG. 5 is a scanning electron microscope image 170 of the solid graphene sheet powder obtained using the graphene production system 100 . The graphene powder includes graphene sheets stacked in layers and has a high purity.
[0051] FIG. 6A is an image 180 of a graphene sheet 182 that was produced by droplet plating graphene ink (made using the graphene production system 100 ) onto a silica (SiO 2 ) substrate. The graphene sheet 182 was observed using an atomic force microscope.
[0052] FIG. 6B is a graph 190 showing measurements made by an atomic force microscope along a line 184 on the graphene sheet 182 . A curve 192 indicates that the thickness of the graphene sheet 182 is not greater than 3 nm. Additional measurements indicate that about 65% of the graphene sheet has a thickness of less than 2 nm.
[0053] FIG. 7 is a graph 200 shows data obtained from a NT-MDT confocal Raman microscopic system for analyzing the bonding of graphene sheets. In this example, a 1.6-nm thick graphene sheet (based on measurements from an atomic force microscope) was excited at a wavelength of 473 nm by the NT-MDT confocal Raman microscopic system, and the molecular bonding structure of the graphene sheet was analyzed. A curve 202 indicates that a G peak 204 at around 1580 cm −1 is narrow and shows a high intensity, indicating that the graphene obtained according to the production process described above has excellent graphitization. In general, the 2D/G intensity ratio of a single-layer graphene is greater than the 2D/G intensity ratio of a double-layer graphene, and the intensity ratio of a 2D peak 206 at around 2720 cm −1 to the G peak 204 is greater than that of the single-layer reduced graphene oxide produced using conventional methods. This shows the graphene produced by the graphene production system 100 has excellent graphitization.
[0054] The graphene production system 100 can also be used to produce graphene oxide by using a process similar to that for producing graphene described above, but with increased DC bias voltage for electrolysis or increased acidity for the electrolyte. In some examples, applying a bias voltage having a higher absolute value and using an electrolyte having a higher acidity level tend to produce more graphene oxide (compared to applying a bias voltage having a lower absolute value and using an electrolyte having a lower acidity level). The graphene oxide can be purified by filtration and rinsing by water. FIG. 8 is a graph showing the characteristic Raman peaks of graphene oxide prepared by using this method.
[0055] Referring to FIG. 9 , an exemplary graphene production system 220 includes a controller 222 that automatically controls the bias voltages applied to the first and second electrodes 102 , 104 . The graphene production system 220 includes other components similar to those of the graphene production system 100 ( FIG. 1 ).
[0056] For example, the controller 222 can have a user interface (not shown) that allows a user to select pre-stored modes of operation. The controller 222 can have a first mode of operation in which a first bias voltage is applied to the electrodes 102 , 104 for a period of time to cause intercalation and a second bias voltage is applied to the electrodes 102 , 104 to cause exfoliation. The controller 222 can have a second mode of operation in which a first bias voltage is applied to the electrodes 102 , 104 for a period of time to cause intercalation, and a second bias voltage and a third bias voltage are alternately applied to the electrodes 102 , 104 to cause exfoliation. The controller 222 may allow the user to choose between a first mode for producing higher throughput but lower quality graphene, or a second mode for producing lower throughput but higher quality graphene. The controller 222 may be programmable such that the user can set a sequence of voltages levels to be applied to the electrodes 102 , 104 over time.
[0057] The graphene production system 220 may include sensors 224 that detect the amount of graphene being collected on the filtration membrane 122 . The sensor signals are sent to the controller 222 . The controller 222 may stop the pump 118 and initiate a process for collecting the graphene. For example, the controller 222 may control a robotic arm (not shown) to retrieve the filtration membrane 122 , wash the filtration membrane 122 with deionized water, scrape the graphene off the filtration membrane 122 , collect the graphene in a container, wash the filtration membrane 122 again, and place the filtration membrane 122 back in the filtration module 116 . The controller 222 may start the pump 118 so that the filtration membrane 122 can continue to collect graphene sheets.
[0058] The graphene production system 220 may determine the amount of graphene produced per unit of time, and adjust the voltage applied to the electrodes 102 , 104 to adjust the production rate. For example, the amount of graphene recovered from the filtration membrane 122 can be divided by the amount of time used for collecting the graphene to generate an estimate of the production rate. The graphene may be automatically analyzed to determine its quality, and the quality information is provided to the controller 222 , which in turn adjusts the bias voltage level to adjust the quality of the graphene. By using various sensors to detect the production throughput and the graphene quality and sending the sensor information to the controller 222 , the graphene production system 220 can control the production throughput and the quality of the graphene to meet preset requirements.
[0059] The controller 222 may include a programmable system having at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system for storing data and instructions. The at least one programmable processor can include, e.g., general purpose microprocessors, special purpose microprocessors, or digital signal processors.
[0060] FIG. 10 is a flowchart of an exemplary procedure 230 for producing graphene. The procedure 230 may be performed by, e.g., the graphene production system 100 ( FIG. 1 ) or the graphene production system 220 ( FIG. 9 ).
[0061] The procedure 230 includes immersing ( 232 ) a first electrode and a second electrode in an electrolyte, the first electrode including graphite. For example, the first electrode can include natural graphite, highly-oriented pyrolytic graphite, pitch-based graphite, carbon fibers, coal, a material including graphite layers, or a material comprising graphite flakes. The first electrode can include two sub-electrodes connected in parallel. The second electrode can include a holder that holds graphite or a mixture of graphite and metal. The metal can include a precious metal that is resistant to acid. The second electrode can include two sub-electrodes connected in parallel. The electrolyte can include hydrogen bromide, hydrochloric acid, or sulfuric acid.
[0062] A first bias voltage is applied ( 234 ) across the first and second electrodes to cause intercalation of the graphite to form a graphite intercalation compound. For example, the first bias voltage can be in a range from 0.5 V to 10 V. The first bias voltage can be a DC voltage or an AC voltage.
[0063] A second voltage is applied ( 236 ) across the first and second electrodes to exfoliate the graphite intercalation compound to produce graphene sheets. For example, the second bias voltage can be in a range from 5 V to 220 V. The second bias voltage can be a DC voltage or an AC voltage.
[0064] The electrolyte is filtered ( 238 ) using a first filter that blocks un-exfoliated graphite particles and allows graphene sheets to pass through. For example, the first filter can include a microporous sieve. The microporous sieve can have a size in a range from 18 mesh to 1,250 mesh.
[0065] The electrolyte is filtered ( 240 ) using a second filter to collect the graphene sheets. The second filter can include a filtration membrane. The filtration membrane can have a pore diameter in a range from 200 nm to 1,200 nm.
[0066] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any inventions or of what may be claimed, but rather as descriptions of features specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.
[0067] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments.
[0068] A number of implementations of the invention have been described. Nevertheless, it will be understood that various modifications can be made without departing from the spirit and scope of the invention. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. Other implementations and applications are also within the scope of the following claims. | An apparatus for large-scale production of graphene and graphene oxide is provided. The apparatus includes a first electrode, a second electrode, an electrobath, a power supply, and a module for filtering and separating the graphene products. Large amounts of graphene and graphene oxide can be produced rapidly using electrochemical exfoliation. High-quality graphene and graphene oxide can be produced under the room temperature in a simple and cost-effective way. | 2 |
This is a continuation of application Ser. No. 08/092,772, filed Jul. 16, 1993, now U.S. Pat. No. 5,513,579.
BACKGROUND OF THE INVENTION
This invention relates to an improved adjustable support mechanism for a computer keyboard or the like. Heretofore there have been various mechanisms for supporting keyboards associated with computer terminals. One such device is disclosed in Smeenge, U.S. Pat. No. 4,616,798, entitled: ADJUSTABLE SUPPORT FOR CRT KEYBOARD, wherein the keyboard support mechanism comprises first and second sets of parallel, equal length articulating arms, which link first and second brackets associated respectively with a keyboard platform and a sliding plate attached beneath a desk top The parallel arms move in a generally vertical plane and maintain the keyboard support platform in generally horizontal position regardless of the position of the platform relative to the desk top. These arms are connected to brackets located in the central portion of the platform remote from the edges of the keyboard support platform. During storage of the keyboard support platform, the arms articulate and the platform is thereby lowered to a retracted position beneath the level of the desk top. During use, the platform is pivoted forward to an extended position. The brackets supporting the inside ends of the arms beneath the desk may be slideably attached to a support plate attached to the bottom side of the desk. In this manner, the assembly may be slid beneath the desk for storage.
Other keyboard supports are illustrated in U.S. Pat. No. 4,625,657; U.S. Pat. No. 4,632,349; U.S. Pat. No. 4,706,919; U.S. Pat. No. 4,776,284; U.S. Pat. No. 4,826,123; and U.S. Pat. No. 4,843,978. Each of these patents describes a support mechanism designed for carrying a computer keyboard or the like. Each employs a parallel arm type mechanism that allows adjustment of the keyboard support.
Another keyboard support mechanism is disclosed in McConnell, U.S. Pat. No. 5,037,054, entitled: ADJUSTABLE SUPPORT MECHANISM FOR A KEYBOARD PLATFORM. U.S. Pat. No. 5,037,054teaches a keyboard support mechanism that employs nonparallel arms to support the keyboard platform. This mechanism does not maintain the keyboard platform in a horizontal position as the arms articulate. This mechanism thus has the benefit that when the keyboard platform is stored under the table, the platform is reoriented to supply greater access to the kneehole of a desk.
The prior art mechanisms have proven to be useful in conjunction with standard desk equipment. However, many desks contain lateral supports which interfere with the operation and/or storage of the prior art keyboard support mechanisms. Moreover, many of the prior art mechanisms tended to bounce when in use, resulting in an unstable work surface. Therefore, there developed the need for a computer keyboard support mechanism which provides the ability to adequately support a computer keyboard, to store the computer keyboard and to provide improved access to the kneehole opening in the desk to which the computer keyboard platform is attached. Further, there is a need for an improved computer keyboard support device which can provide unlimited positioning of the orientation of the keyboard platform and at the same time, provide a stable surface for the keyboard.
It should also be appreciated that there has recently been much attention paid to repetitive strain injury (RSI), including carpal tunnel syndrome. These injuries have been associated with extended typing on computer keyboards. It has been suggested that the ability to type with less bend in the wrist may reduce the risk of injury. Therefore, there remains a need for a keyboard support that is adjustable, to potentially reduce the risk of repetitive strain injury such as carpal tunnel syndrome.
SUMMARY OF THE INVENTION
In a principal aspect, the computer keyboard support assembly of the present invention comprises a platform suitable for supporting a keyboard mechanism having one end of an arm pivotally mounted to the platform and the other end pivotally mounted to a mounting bracket which is attached to the underside of a work surface. A compensating mechanism utilizing a driving mechanism interacting with the pivot mountings for the arm and controlling the orientation of the platform, as the platform is moved to and from a storage and use position.
As another aspect of the invention there is provided a mechanism that allows the platform to be tilted and locked in a tilted position. This tilt can create either a positive or a negative slope with respect to the platform.
In a further aspect of the invention, there is provided a mechanism for locking a keyboard to the platform. This mechanism allows the keyboard to be securely attached to the platform as the support arms are moved from an extended position to a storage position.
In still another aspect of the invention there is a slide mechanism associated with the mounting bracket that allows the entire support assembly to be moved inwardly or outwardly with respect to the front edge of the work surface.
In still a further aspect of the invention, the keyboard support assembly can be swung into a storage position substantially adjacent to the underside of the work surface. Thus, when the support arms of the mechanism are pivoted from the extended position to the storage position, the keyboard platform is stored beneath the work surface in a manner that does not limit the access to the kneehole opening of the desk.
Yet a further aspect of the invention utilizes a pair of support arms connecting the edges of the platform and a bracket attached to the underside of a desk.
Thus, it is an object of the invention to provide an improved adjustable support assembly for a keyboard platform.
It is a further object of the invention to provide an improved platform support assembly for a computer keyboard which includes the ability to store a keyboard mechanism under a desk that has a lateral support.
Another object of the invention is to provide a computer keyboard support assembly that maintains the orientation of the keyboard platform as the support arms positioned at either end of said platform are pivoted through an arc in a vertical plane.
Still another object of the invention is to provide a computer keyboard support assembly that can be stored easily under a work surface and still maintain access to the kneehole.
A further object of the invention is to provide a computer keyboard support assembly which allows for orientation of the computer keyboard such as to alleviate strain upon the operator and potentially reduce the incidence of repetitive strain injury.
Yet another object of the inventions is to provide a computer keyboard support assembly of simplified and rugged construction easily manufactured to be both durable and useful.
These and other objects, advantages and features will be set forth in the detailed description which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
In the detailed description which follows, reference will be made to the drawings comprised of the following Figures;
FIG. 1 is a side elevation of the preferred embodiment of the keyboard support assembly of the invention:
FIG. 2 a side elevation of the preferred embodiment of the keyboard support assembly of the invention attached to the underside of a work surface, illustrating the motion of the invention in phantom lines;
FIG. 3 is a perspective view of the support mechanism of the invention, illustrating the location of the tilt adjustment mechanism and showing the platform and desk in phantom lines;
FIG. 4 is perspective view of the tilt adjustment mechanism;
FIG. 5 is a partial front cross-section of FIG. 4;
FIG. 6 is a cross-section of the compensating mechanism associated with the support arm;
FIG. 7 is an exploded drawing, illustrating the compensating mechanism;
FIG. 8 is a side elevation, illustrating an embodiment with a slide mechanism;
FIG. 9 a cross-section of FIG. 8 along line IX--IX;
FIG. 10 is a side view of the cam locking mechanism;
FIG. 11 is a cross-section of FIG. 10 along line X--X;
FIG. 12 is a cross-section of an alternative compensating mechanism associated with the support arm;
FIG. 13 is a cross-section of FIG. 12 along line XII--XII.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Before describing the component parts of the invention, a brief description of the manner in which the assembly operates will be beneficial in illustrating the construction of the assembly. Reference is thus directed to FIGS. 1, 2 and 3. As shown in FIGS. 1 and 2, a keyboard 10 is mounted on a keyboard platform 12. The keyboard platform 12 is supported by a pair of spaced support arms 21, 22. The first ends of support arms 21, 22 arc pivotally mounted to opposite sides of the keyboard platform 12 and the second ends of the support arms 21, 22 are pivotally mounted to a mounting bracket 24. The mounting bracket 24 is associated with or attached to the underside of a work surface 16.
As illustrated in FIG. 3, the support arms 21, 22 pivot about a first horizontal pivot axis 25 passing through the mounting bracket 24. As the support arms 21, 22 pivot about the first horizontal pivot axis 25, the computer keyboard 10 and the platform 12 are moved from a work position to a storage position under the work surface 16. As the support arms 21, 22 pivot about the first horizontal pivot axis 25, the keyboard platform 12 pivots about a second horizontal pivot axis 27 with respect to the support arms 21, 22 thereby maintaining the keyboard platform 12 in the same orientation with respect to the work surface 16, the second horizontal pivot axis 27 being substantially parallel to the first horizontal pivot axis 25.
The orientation of the keyboard platform 12 is generally horizontal. However, the keyboard platform 12 is also adjustable and can be tilted about a horizontal axis. In a preferred embodiment this horizontal axis corresponds with the second horizontal pivot axis 27. This tilt allows the angle of the keyboard platform 12 and the associated keyboard 10 to be altered to the preferred position of the user. FIG. 1 illustrates in phantom lines how the keyboard platform 12 can be tilted with either a positive and a negative tilt.
This tilt feature, in combination with the pivoting motion of the support arms 21, 22 allows the keyboard 10 to be efficiently stored under the work surface 16, even if the work surface 16 has an obstruction such as a lateral support 18.
Another preferred embodiment of the invention (shown in FIGS. 8 and 9) includes a sliding mechanism 23 which allows the mounting bracket 24 to be moved in a direction perpendicular to the front edge 29 of the work surface 16. Such a slide mechanism 23 permits further adjustment for the computer platform 12 and the associated keyboard 10. The bracket 24 and slide mechanism 23 may also be associated with a vertical axis, pivot mechanism (not shown) allowing the entire assembly to pivot about a vertical axis.
FIG. 3 illustrates the basic components of a preferred embodiment of the present invention. The keyboard platform 12 (shown in phantom) is mounted upon a casing 28. Any appropriate means for mounting is acceptable, in the preferred embodiment screws or bolts are used depending on the material used for the keyboard platform 12. A pivot shaft or rod 26 passes through the casing 28 in a manner that permits rotation of the casing 28 about the shaft 26. The shaft 26 is pivotally associated at its ends with the first ends of the support arms 21, 22. The second ends of the support arms 21, 22 are in turn pivotally associated with a mounting member which is shown in FIG. 3 as the mounting bracket 24. The mounting bracket 24 is mounted on the underside of the work surface 16. As stated above, the mounting member may also include a slide mechanism 23 which allows the bracket 24 to move in a direction perpendicular to the front edge 29 of the work surface 16.
The preferred embodiment of FIG. 3 illustrates two support arms 21, 22 spaced apart about the same distance as the width of the keyboard platform 12.
The width of the keyboard platform 12 is defined by its two opposite sides 31.
It should be appreciated that the support arms 21, 22 can be located intermediate the opposite sides 31 of the keyboard platform 12. Indeed, the present invention includes an embodiment wherein only one support arm 22 is utilized, said support arm 22 being associated with the central portion of the keyboard platform 12. Such a single support arm assembly is, however, less preferred as it does not provide the stability of an assembly with two spaced apart support arms 21, 22.
FIG. 3 further illustrates a locking lever 20 which actuates a locking mechanism within casing 28. As more fully described below, this locking mechanism preferably fixes the angle of tilt about the second horizontal pivot axis 27 and controls the rotation of platform 12 about the first horizontal pivot axis 25.
FIGS. 6 and 7 illustrate the relationship of the support arm 22 with both the mounting bracket 24 and the pivot shaft 26. As shown, the support arm 22 is pivotally mounted on the inside surface of the mounting bracket 24. Any appropriate pivotal mount will suffice. In the preferred embodiment, the pivotal mount is a bolt 63 positioned along the first horizontal pivot axis 25 associated with both the mounting bracket 24 and the support arm 22. The mounting bracket 24 is supplied with a first spring post 60 which extends from the bracket 24 and is adapted to receive one end of a tension spring 52. The support arm 22 likewise includes a second spring post 61 which extends in a direction substantially the same as the first spring post 60 and is adapted to receive the opposing end of tension spring 52. Tension spring 52 acts to counterbalance the weight of the support arms 21, 22 and the computer keyboard platform 12, thereby keeping the platform 12 and the support arms 21, 22 in a home position. This home position may be substantially horizontal or it may be set at any other desirable angle by altering the size and tension of the spring 52.
FIGS. 6 and 7 further illustrate a compensating mechanism that maintains the orientation of the keyboard platform 12 while the support arms 21, 22 are pivoted about the first horizontal pivot axis 25. Referring specifically to FIG. 7, the compensating mechanism of the preferred embodiment comprises a fixed sprocket 54, a rotating sprocket 55, and an endless compensating belt 50 keyed to the sprockets 54, 55. The fixed sprocket 54 is nonrotatably attached to the mounting bracket 24. The nonrotatably attachment may be done by a spline or any other appropriate attaching means. The compensating belt 50 is associated with the nonrotating sprocket 54. In the preferred embodiment, the belt 50 consists of a perforated tape where the perforations arc associated with the teeth of the fixed sprocket 54. An appropriate perforated tape is commercially available under the trade name Dymetrol. The compensating belt 50 is also associated with the rotating sprocket 55. In a similar manner, in a preferred embodiment, the perforations of the belt 50 are associated with the teeth of the rotating sprocket 55.
The rotating sprocket 55 is mounted upon the pivoting shaft 26 in a manner such that when the shaft 26 pivots, the rotating sprocket 55 also pivots. An example of such a mounting is shown in FIGS. 6 and 7. The pivot shaft 26 is comprised of three components, an inner shaft 34, a tight outer shaft 32, and a left outer shaft 33 (shown in FIG. 4). The rotating sprocket 55 is mounted on one of the outer pivot shafts, 32, 33 and secured by washer 58 and clip 48. Thus, when the support arms 21, 22 are rotated about the first horizontal pivot axis 25, the compensating belt 50 will be wrapped around the fixed sprocket 54 which, in turn, will cause rotation of the rotating sprocket 55 and this, in turn, would cause a corresponding rotation of the outer pivot shaft 32, 33. Because the orientation of the keyboard platform 12 is related to the position of the outer shaft 32, 33, as the pivot shaft 26 rotates, so will the keyboard platform 12. This rotation keeps the orientation of the keyboard platform 12 unchanged.
The compensation mechanism is preferably further supplied with clutch plate 56 to avoid slippage and/or movement of the rotating sprocket 55 due to external pressures. The clutch plate 56 is affixed to the outside of rotating sprocket 55. In a preferred embodiment, the clutch plate 56 is an integral part of the rotating sprocket 55. The clutch plate 56 is designed to engage the washer 58 and thereby keep the rotating sprocket 55 from rotating and resulting in the position of the keyboard platform 12 being fixed.
It is desirable that the compensating belt 50 of the compensating mechanism be taut at all times. To facilitate this the compensating mechanism may include an idler assembly. An example of an idler assembly may include an idler wheel which rides on compensating belt 50. The idler wheel is spring biased to apply pressure to the compensating belt 50. In this manner the compensating belt 50 is kept taut during operation even though it may stretch during use. Other types of idler systems could also be used, including a set screw capable of tightening the belt.
In a particularly preferred embodiment of the invention, there is a separate compensating mechanism associated with each of the support arms 21, 22. Such a design reduces the stress on the components of the compensating mechanism. Each compensating mechanism would be enclosed in an arm housing 64 to isolate the sprockets 54, 55 and the compensating belt 50 from the operator.
The compensating mechanism of the present invention can have alternative constructions. For example, the sprockets 54, 55 and belt 50 may be replaced with a Scar and chain assembly or a Sear and belt assembly wherein the belt is adapted to associate with the cogs of the gear. As a further example the compensating mechanism could incorporate a planetary gear system in which one planet gear or a series of planet gears rotates about another fixed sun gear(s). In each such assembly the appropriate compensating movement can be accomplished.
Another alternative embodiment of the compensating means is shown in FIGS. 12 and 13. In this alternative embodiment, a fixed beveled gear 66 is nonrotatably mounted on the mounting bracket 24. The fixed beveled gear 66 is associated with a first pinion gear 70. The first pinion gear 70 is positioned at and engages one end of a pinion shaft 74. The opposing end of pinion shaft 74 engages a second pinion gear 72. The second pinion gear 72 is associated with a rotating beveled gear 68. The opposing ends of the pinion shaft 74 are associated with a first pinion shaft bearing 76 and a second pinion bearing 78, respectively. These pinion shaft bearings 76, 78 allow for rotation of the pinion shaft 74 while pinion gears 70, 72 are in operative engagement with the respective bevel gears 66, 68. In addition, the pinion shaft bearings 76, 78 are affixed to the keyboard tray support arm 22.
In operation, the keyboard tray support arm 22 is pivoted about the first substantially horizontal axis 25. This pivot action causes the first pinion gear 70 to move around fixed beveled gear 66. This motion results in the rotation of the pinion shaft 74 and a corresponding rotation of the second pinion gear 72. The rotation of the second pinion gear 72 drives the second beveled gear 68, which in turn, rotates the outer shaft 32. The rotation of the outer shaft 32 acts to keep the orientation of the keyboard platform 12 unchanged with respect to horizontal, as the support arm 22 is pivoted.
The lock mechanism within the casing 28 is illustrated in FIGS. 4 and 5. The lock mechanism is actuated by movement of locking lever 20 in a guideway 30. The lock mechanism performs two functions: first, it provides a means for locking the assembly in a selected vertical position; second, it provides a means for locking the keyboard platform 12 at a particular tilt angle. Preferably both of these locking functions are actuated by the single locking lever 20.
The assembly is locked in a selected vertical position by moving the locking lever 20 laterally from one extreme of guideway 30 to the other. The locking lever 20 has two setting: a locked position preventing the pivoting of the support arms 21, 22 about the first horizontal pivot axis 25; and free moving position allowing the support arms 21, 22 to pivot about the first horizontal pivot axis 25.
Locking at a particular vertical position is accomplished through the association of a locking cam 42 with pivot shaft 26. The interaction of the pivot shaft 26 and the locking cam 42 is shown in more detail in FIGS. 10 and 11. The inner shaft 34 spans the distance between the two support arms 21, 22 and passed through the locking cam 42. The inner shaft 34 provides support for both outer shafts 32, 33. The two outer shafts 32, 33 are positioned concentrically around the inner shaft 34. Each outer shaft 32, 33 has a cam bearing end 41. This cam bearing end 41 defines a cam bearing surface 36.
This cam bearing surface 36 may be created in any appropriate way such as a washer or an integral flange. The movement of the locking lever 20 in guideway 30 causes the locking cam 42 to engage or disengage the cam bearing surface 36 of the outer shafts 32, 33 and the surface of the inner shaft 34.
When the locking cam 42 engages the respective cam bearing surfaces 36, the clutch plate 56 is forced into contact with washer 58 fixing rotating sprocket 55 in place. As a result, the support arms 21, 22 cannot pivot about the first horizontal pivot axis 25 and the vertical position of the keyboard platform 12 is locked. Conversely, when the locking cam 42 disengages the respective surfaces, the clutch plate 56 disengages the washer 58, the rotating sprocket 55 is free to rotate and thus the support arms 21, 22 are free to pivot and the vertical position of the keyboard platform 12 can be adjusted.
The tilt of the keyboard platform | 2 is preferably also controlled by the locking lever 20 although a separate actuator may be employed. The locking lever 20 is associated with a locking plate 44. The locking plate 44 engages a clutch surface 40 of the pivot shaft 26. When locking plate 44 engages the clutch surface 40, it locks the tilt angle of the keyboard platform 12. The locking plate 44 is disengaged from the clutch surface 40 when the locking lever 20 is lifted out of a notched portion 43 of the guideway 30. More specifically, in a preferred embodiment, the locking lever 20 passes through a slot 45 in the locking plate 44. The locking plate 44 is biased by spring 46 to engage the clutch surface 40. As the locking lever 20 is lifted out of the notch portion 43 of the guideway 30, it lifts the locking plate 44 by engaging the upper surface of the slot 45. This lifting causes the locking plate 44 to pivot about a fulcrum 47, counteracting the biasing force of spring 46 and resulting in disengagement of the clutch surface 40. With this disengagement the casing 28 is free to pivot about the second horizontal pivot axis 27 as defined by the pivot shaft 26.
The clutch surface 40 may be created by any appropriate method including a knurled or splined surface on the pivot shaft 26. The locking plate 44 is adapted so as to mate with the clutch surface in a non-slip manner.
The tilt mechanism is also supplied with torsion springs 38 which interact with the casing 28 around the pivot shaft 26 such that the keyboard platform 12 has a tilt home position. This tilt home position may be horizontal or may be adjusted to any desired angle. More specifically, when the keyboard platform 12 is tilted, the torque upon the springs 38 is increased and that torque is maintained by locking the locking plate 44 against the clutch surface 40, thereby maintaining the computer keyboard platform 12 at the appropriate tilt. When the locking plate 44 is released from the clutch surface 40, the springs 38 will bring the keyboard platform 12 to the tilt home position.
In one embodiment of the present invention it is also advantageous to supply the keyboard platform 12 with a keyboard clamp 14. The keyboard clamp 14 operates to secure the keyboard 10 to the keyboard platform 12. The keyboard clamp 14 is shown in FIG. 1. It is mounted on the keyboard platform 12 and acts upon the front and rear of the keyboard 10. The clamp 14 applies pressure to the keyboard 10, forcing it down onto the keyboard platform 12, thereby securing it to the keyboard platform 12 during adjustment or storage.
In one embodiment of the present invention, the clamp 14 may be integral to the platform 12. Such an embodiment is illustrated in FIG. 1.
The present invention can also be supplied with power assist to aid in the adjustment of the device. Examples of such power assist would be a servo motor or an actuating cylinder that would act upon the support arms 21, 22 in a manner that would cause them to pivot about the first substantially horizontal axis 25. Such power assist provides the advantage of not requiring the operator to lift any weight and may provide the convenience of push button control.
It is possible to vary the construction of the invention by providing additional elements or eliminating other elements, without departing from the spirit and the scope of the invention. For example, as mentioned above, the assembly could include a slide mechanism 23 associated with the underside of the work surface 16, thereby allowing the entire assembly to be moved inwardly and outwardly with respect to the front edge 29 of the work surface 16. Additionally, such a slide mechanism 23 could be associated with the vertical pivot which would allow the entire assembly to pivot about a vertical axis passing through the work surface 16. In addition, it is foreseeable that a vertical pivot could be associated with the keyboard platform 12, such that the computer keyboard platform 12 itself could pivot about a vertical axis passing through or near the platform 12. Such vertical pivot mechanisms are taught in the prior art and are well known to one skilled in the art. Thus, while there has been set forth here the preferred embodiment of the invention; it is understood that the invention is to be limited only by the following claims or their equivalents. | The computer keyboard support assembly of the disclosure comprises a platform suitable for supporting a keyboard mechanism having one end of an arm pivotally mounted to the platform and the other end pivotally mounted to a mounting bracket which is attached to the underside of a work surface. A compensating mechanism utilizing a driving mechanism interacting with the pivot mountings for the arm and controlling the orientation of the platform, as the platform is moved to and from a storage and use position. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 10/536,101 filed on Feb. 22, 2005 (now abandoned), which is a 35 U.S.C. 371 national application of PCT/DK2004/000558 filed Aug. 23, 2004, which claims priority or the benefit under 35 U.S.C. 119 of Danish Application No. PA 2003 01201 filed Aug. 22, 2003 and U.S. Provisional Application No. 60/497,455 filed Aug. 22, 2003, the contents of which are fully incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to the construction of variants of fungal alpha-amylases.
BACKGROUND OF THE INVENTION
WO 0134784 discloses variants of a fungal alpha-amylase. Pdb files 2AAA, 6taa and 7taa (available at rcsb.org) show the amino acid sequences and three-dimensional structures of fungal alpha-amylases. WO 9943794 discloses the amino acid sequence and three-dimensional structure of a maltogenic alpha-amylase from Bacillus stearothermophilus , known as Novamyl®.
SUMMARY OF THE INVENTION
The inventors have developed a method of altering the amino acid sequence of a fungal alpha-amylase to obtain variants with improved anti-staling effect and a higher degree of exo-amylase activity (increased ratio of exo-amylase to endo-amylase), and they have used the method to construct such variants. The variants may be useful for anti-staling in baked products.
Accordingly, the invention provides a method of constructing fungal alpha-amylase variants based on a comparison of three-dimensional (3D) structures of the fungal alpha-amylase and a maltogenic alpha-amylase. One or both models includes a substrate. The invention also provides novel fungal alpha-amylase variants and use of the variants in the preparation of dough and baked products.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows an alignment of fungal amylases SEQ ID NO: 2, 3 and 4.
FIG. 2 shows an alignment of the 3D structures 1QHO for the maltogenic alpha-amylase Novamyl (SEQ ID NO: 1) at top and 6taa for a fungal alpha-amylase (SEQ ID NO: 2) below. Details are described in Example 1.
DETAILED DESCRIPTION OF THE INVENTION
Fungal alpha-amylase
The method of the invention uses an amino acid sequence of a fungal alpha-amylase and a three-dimensional model for the fungal alpha-amylase. The model may include a substrate.
The fungal alpha-amylase may be one of the following having the indicated amino acid sequence and a three-dimensional structure found under the indicated identifier in the Protein Data Bank (available at rcsb.org): acid alpha-amylase from Aspergillus niger (2AAA, SEQ ID NO: 3), alpha-amylase (Taka amylase) from Aspergillus oryzae (6taa or 7taa, SEQ ID NO: 2) or alpha-amylase from Thermomyces lanuginosus (SEQ ID NO: 4, WO 9601323). Alternatively, the fungal alpha-amylase may be a variant having at least 70% amino acid identity with SEQ ID NO: 2, e.g. a variant described in WO 0134784.
3D structures for other fungal alpha-amylases may be constructed as described in Example 1 of WO 9623874. To develop variants of a fungal alpha-amylase without a known 3D structure, the sequence may be aligned with a fungal alpha-amylase having a known 3D structure. The sequence alignment may be done by conventional methods, e.g. by use the software GAP from UWGCG Version 8. FIG. 1 shows an alignment of SEQ ID NO: 4 (without a known 3D structure) with SEQ ID NO: 2 and 3 (with known structures).
Maltogenic alpha-amylase
The method also uses an amino acid sequence of a maltogenic alpha-amylase (EC 3.2.1.133) and a three-dimensional model of the maltogenic alpha-amylase. The model may include a substrate. The maltogenic alpha-amylase may have the amino acid sequence have the amino acid sequence shown in SEQ ID NO: 1 (in the following referred to as Novamyl). A 3D model for Novamyl with a substrate is described in U.S. Pat. No. 6,162,628 and is found in the Protein Data Bank with the identifier 1QHO. Alternatively, the maltogenic alpha-amylase may be a Novamyl variant described in U.S. Pat. No. 6,162,628. A 3D structure of such a variant may be developed from the Novamyl structure by known methods, e.g. as described in T. L. Blundell et al., Nature, vol. 326, p. 347 ff (26 Mar. 1987); J. Greer, Proteins: Structure, Function and Genetics, 7:317-334 (1990); or Example 1 of WO 9623874.
Superimposition of 3D Models
The two 3D models may be superimposed by aligning the amino acid residues of each catalytic triad by methods known in the art. This may be based on the deviations of heavy atoms (i.e. non-hydrogen atoms) in the active sites, e.g. by minimizing the sum of squares of deviations. Alternatively, the superimposition may be based on the deviations of the three pairs of C-alpha atoms, e.g. by minimizing the sum of squares of the three deviations or by aligning so as to keep each deviation below 0.8 Å, e.g. below 0.6 Å, below 0.4 Å, below 0.3 Å or below 0.2 Å.
The structural alignment may be done by use of known software. In the structurally aligned models, pairs of residues from different sequences are considered to be aligned when they are located close to each other. The following software may be used:
DALI software, available at ebi.ac.uk/dali.
CE software available at cl.sdsc.edu.
STAMP software available at compbio.dundee.ac.uk/Software/Stamp/stamp.html.
Protein 3Dhome at lecb.ncifcrf.gov/˜tsai.
Yale Gernstein Lab—spare parts at bioinfo.mbb.yale.edu/align.
Structural alignment server at molmovdb.org/align.
Substrate
A 3D structure of the enzyme(s) having a substrate or substrate analog in the active site binding cleft. A “substrate” could be a substrate bound in an inactive or active enzyme, or a substrate inhibitor like acarbose bound in the active site, or a modelled substrate in the active site, a docked substrate in the active site, or a substrate superimposed into the enzyme of interest and taken from a homologous 3D structure having such substrate or substrate analog bound in the active site.
Selection of Amino Acid Residues
In the superimposed 3D models, amino acid residues in the fungal alpha-amylase sequence are selected by two criteria: Firstly, fungal alpha-amylase residues <11 Å from a substrate (i.e. residues having a C-alpha atom located <11 Å from an atom of a substrate) are selected. Secondly, fungal alpha-amylase residues >0.8 Å from any maltogenic alpha-amylase residue (i.e. fungal alpha-amylase residues having a C-alpha atom >0.8 Å from the C-alpha atom of any maltogenic alpha-amylase residue) are selected.
Alteration of Fungal Alpha-Amylase Amino Acid Sequence
One or more of the following alterations are made to the fungal alpha-amylase sequence:
Deletion or Substitution
A fungal alpha-amylase residue <11 Å from a substrate and >0.8 Å from any maltogenic alpha-amylase residue may be deleted or may be substituted with a different residue.
The substitution may be made with the same amino acid residue as found at a corresponding position in the maltogenic alpha-amylase sequence or with a residue of the same type. The type indicates a positively charged, negatively charged, hydrophilic or hydrophobic residue, understood as follows (Tyr may be hydrophilic or hydrophobic):
Hydrophobic amino acids: Ala, Val, Leu, Ile, Pro, Phe, Trp, Gly, Met, Tyr
Hydrophilic amino acids: Thr, Ser, Gln, Asn, Tyr, Cys
Positively charged amino acids: Lys, Arg, His
Negatively charged amino acids: Glu, Asp
The fungal alpha-amylase residue may be substituted with a larger or smaller residue depending on whether a larger or smaller residue is found at a corresponding position in the maltogenic alpha-amylase sequence. In this connection, the residues are ranked as follows from smallest to largest: (an equal sign indicates residues with sizes that are practically indistin-guishable):
G<A=S=C<V=T<P<L=I=N=D=M<E=Q<K<H<R=F<Y<W
Insertion
One or more amino acid residues may be inserted at a position in the fungal alpha-amylase sequence corresponding to one or more residues in the maltogenic alpha-amylase sequence which are <11 Å from a substrate and which are >0.8 Å from any fungal alpha-amylase residue. The insertion may be made with the same residue as in the maltogenic alpha-amylase sequence or with another amino acid residue of the same type. The type indicates a positively charged, negatively charged, hydrophilic or hydrophobic residue, as above.
Where the maltogenic alpha-amylase sequence contains a consecutive stretch (a peptide loop) of residues which are >0.8 Å from any fungal alpha-amylase residue and of which some are <11 Å from a substrate, the insertion at the corresponding position in the fungal alpha-amylase sequence may consist of an equal number of residues, or the insertion may have one or two fewer or more residues. Thus, in the case of a stretch of 5 such residues in the maltogenic alpha-amylase sequence, the insertion may be made with 3-7 residues, e.g. 3, 4, 5, 6 or 7 residues. Each inserted residue may be the same as one of the maltogenic alpha-amylase residues or of the same type.
Optional Further Alterations of the Fungal Alpha-Amylase Sequence
Optionally, one or more other residues in the fungal alpha-amylase sequence may be substituted. The substitution may be made as described in WO 0134784 and may improve the thermostability of the variant.
A fungal alpha-amylase residue <11 Å of a substrate and <0.8 Å of a maltogenic alpha-amylase residue may be substituted with a residue identical to or of the same type as the corresponding maltogenic alpha-amylase residue, or with a larger or smaller residue depending on whether the corresponding maltogenic alpha-amylase residue is larger or smaller.
Degree of Exo-Activity
The degree of exo amylase activity is given as a relative activity compared to the endo amylase activity. The endo activity can be measured by a number of well known assays e.g. starch iodine, Phadebas (Amersham now GE Healthcare), or AZCL-amylose (Megazyme). The exo activity is preferably a measure of the small malto-oligomers released from starch at initial phases of hydrolysis. It is preferably measured by total carbohydrate after removal of the remaining starch, by the exo activity assay described below or similar method, but could be measured by other means e.g. the sum of oligomers by HPAEC-PAD (Dionex) or sum of oligomers after size exclusion chromatography.
Endo-Amylase Activity Assay:
1 mL resuspended Phadebas substrate (0.25 tablets/mL 50 mM sodium acetate, 1 mM CaCl 2 , adjusted to pH 5.7) is incubated with 25 micro-L enzyme for 15 min at 40° C. with agitation. The reaction is stopped by addition of 0.5 mL 1 M NaOH and the mixture is centrifuged in a table centrifuge at 14,000 RPM. The absorbance of the supernatant at 620 nm is measured. The activity is determined by comparing to a standard with declared activity (BAN 480 L, 480 KNU/g)
Exo-Amylase Activity Assay:
900 μL 3.3% solubilized waxy maize starch (3.3% starch is boiled in 50 mM sodium acetate, 1 mM CaCl 2 , pH 5.7 for 5 min and cooled to 40° C.) is incubated with 100 micro-L enzyme at 40° C. with stirring. After appropriate reaction time the remaining starch is precipitated by addition of 450 micro-L 4° C. 96% ethanol. The precipitate is immediately removed by centrifugation at 3000 G for 20 min. The total carbohydrate in the supernatant is determined by mixing 200 micro-L supernatant with 50 micro-L 2% tryptophan and 900 micro-L 64% sulfuric acid. The mixture is heated for 15 min at 95° C. and the absorbance at 630 nm is measured after cooling to room temperature. The activity is determined by comparing with the absorbance of glucose standards in the same assay. One unit is defined as the amount of enzyme that at initial rates liberates 1 mg oligomeric products (products that are not precipitated by ethanol) per min.
Fungal Alpha-Amylase Variants
A fungal alpha-amylase variant may be a polypeptide which:
a) has an amino acid sequence having at least 70% identity to SEQ ID NO: 2, 3 or 4; and
b) comprises an amino acid alteration which is deletion, substitution or insertion as described below, and
c) has the ability to hydrolyze starch.
The identity may be at least 80%, at least 90% or at least 95%. Amino acid identity may be determined as described in U.S. Pat. No. 6,162,628.
Production of Fungal Alpha-Amylase Variants
A polypeptide having the resulting amino acid sequence may be produced by conventional methods, generally involving producing DNA with a sequence encoding the polypeptide together with control sequences, transforming a suitable host organism with the DNA, cultivating the transformed organism at suitable conditions for expressing and optionally secreting the polypeptide, and optionally recovering the expressed polypeptide.
DNA encoding any of the above fungal alpha-amylase variants may be prepared, e.g. by point-specific mutation of DNA encoding the parent fungal alpha-amylase. This may be followed by transformation of a suitable host organism with the DNA, and cultivation of the transformed host organism under suitable conditions to express the encoded polypeptide (fungal alpha-amylase variant). This may be done by known methods.
Optional Screening of Fungal Alpha-Amylase Variants
Optionally, one or more expressed polypeptides may be tested for useful properties. This may include testing for the ability to hydrolyze starch or a starch derivative by a conventional method, e.g. a plate assay, use of Phadebas tablets or DSC on amylopectin. Also, the polypeptide may be tested for thermostability, and a more thermostable one may be preferred. Finally, the polypeptide may be tested by adding it to a dough, baking it and testing the firmness of the baked product during storage; a polypeptide with anti-staling effect may be selected as described in WO 9104669 or U.S. Pat. No. 6,162,628.
Optional Gene Recombination
Optionally, DNA encoding a plurality of the above fungal alpha-amylase variants may be prepared and recombined, followed by transformation of a suitable host organism with the recombined DNA, and cultivation of the transformed host organism under suitable conditions to express the encoded polypeptides (fungal alpha-amylase variants). The gene recombination may be done by known methods.
Dough and Baked Product
The variants are useful in the preparation of dough and baked products from dough. Particularly, the variant may be added in an amount which is effective to retard the staling of the baked product.
The dough may be leavened e.g. by adding chemical leavening agents or yeast, usually Saccharomyces cerevisiae (baker's yeast). The dough generally comprises flour, particularly wheat flour. Examples of baked products are bread and rolls.
The dough may comprise an additional enzyme, e.g. a second amylase, a protease or peptidase, a transglutaminase, a lipolytic enzyme, a cellulase, a xylanase or an oxidoreductase, e.g. a carbohydrate oxidase with activity on glucose and/or maltose. The lipolytic enzyme may have triacyl glycerol lipase activity, phospholipase activity and/or galactolipase activity, e.g. as described in WO 9953769, WO 9826057 or WO 0032758.
EXAMPLES
Example 1
Construction of Variants of Fungal Alpha-Amylase from A. oryzae
Two 3D structures with substrates were used: 6taa for a fungal alpha-amylase (SEQ ID NO: 2) and 1QHO for a maltogenic alpha-amylase (Novamyl, SEQ ID NO: 1), wherein the substrates are indicated as ABC for 6taa and as ABD for 1QHO. The two structures were superimposed using the heavy atoms of the three C-alpha atoms at the catalytic triad: D206, E230 and D297 for 6taa, and D228, E256 and D329 for Novamyl. The superimposed structures were analyzed, and the result is shown in FIG. 2 with the Novamyl sequence at the top and the fungal alpha-amylase sequence below.
The following fungal alpha-amylase residues were found to have a C-alpha atom <11 Å from an atom of either substrate: 13, 14, 15, 18, 31, 32, 33, 34, 35, 36, 61, 62, 63,64, 66, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 94, 117,118, 119, 120, 121, 122, 123, 124,125, 126, 127, 151, 152, 153, 154, 155, 156, 157, 158, 160,161, 162, 164, 165,166, 167,168, 169, 170, 171, 172, 173, 174, 175, 204,205, 206, 207, 208, 209, 210, 211,216,228, 229,230, 231, 232, 233, 234, 235, 236, 237, 238, 239,242, 250,251, 252, 253, 254, 255, 256,257, 258, 259, 260, 275, 292, 294,295, 296, 297, 298, 299, 304, 328, 338, 239, 340, 341, 342, 343, 344. They are indicated by the first underlining in FIG. 2 .
The following fungal alpha-amylase residues were found to be included in either of the above subsets (<11 Å from a substrate or in a loop) and to have a C-alpha atom >0.8 Å from the C-alpha atom of any Novamyl residue: 15, 32, 33, 34, 35, 36, 63, 64, 73, 74, 75, 76, 77, 119, 120, 125, 126, 151, 152, 155, 156, 167, 168, 169, 170, 171, 172, 211, 233, 234, 235, 236, 237, 238, 239. They are indicated by the second underlining in FIG. 2 .
Variants were constructed by substituting a selected residue in SEQ ID NO: 2 (fungal amylase) as indicated below:
Selected
Corresponding
residue in
residue in
Particular
SEQ ID NO: 2
SEQ ID NO: 1
Criteria for
substitution in
(fungal amylase)
(Novamyl)
substitution
SEQ ID NO: 2
Q35
K44
larger and/or
Q35K/R
positive
Y75
T84
smaller
Y75A/F
Y155
W177
larger and/or
Y155W
hydrophobic
L166
F188
larger and/or
L166F
hydrophobic
G167
T189
larger and/or
G167T
hydrophilic
N169
P191
smaller and/or
N169P
hydrophobic
T170
A192
smaller and/or
T170A
hydrophobic
L232
Y258
larger
L232Y
D233
G259
smaller and/or
D233G
hydrophobic
G234
D260
larger and/or
G234D
negative
Y252
F284
smaller and/or
Y252F
hydrophobic
Y256
T288
smaller and/or
Y256T
hydrophilic
Variants were constructed by altering a subsequence with insertion of an additional residue in SEQ ID NO: 2 (fungal amylase) to match the number of residues in SEQ ID NO: 1, as indicated below:
Alteration In SEQ ID NO: 2 (fungal amylase)
166LGDNTV171 to FTDPAGF (Novamyl loop (long))
168-171 (DNTV) substituted with DPAGF (Novamyl loop)
168-171 (DNTV) substituted with DPAGL (Novamyl loop with
adjustments in last part)
168-171 (DNTV) substituted with DPAGC (Novamyl loop with
adjustments in last part)
Further, amino acid alterations were combined as follows:
Alteration with insertion
Substitutions
in SEQ ID NO: 2
in SEQ ID NO: 2
D233G + G234D
Q35K + Y75F + D168Y
Q35R + Y75F
Q35R + Y75F + D168Y
168-171 (DNTV)
Y75A
substituted with DPAGF
168-171 (DNTV)
Q35K + Y75A
substituted with DPAGF
168-171 (DNTV)
Q35K + Y75A + D233G + G234D
substituted with DPAGF
168-171 (DNTV)
Y75A + G234D
substituted with DPAGF
168-171 (DNTV)
Y75A + D233G + G234D
substituted with DPAGF
166-171 (LGDNTV)
Y75A
substituted with FTDPAGF
166-171 (LGDNTV)
Q35K + Y75A
substituted with FTDPAGF
166-171 (LGDNTV)
Q35K + Y75A + D233G + G234D
substituted with FTDPAGF
Example 2
Construction of Variants of Acid Amylase from A. niger
The three-dimensional structure 2AAA for the acid alpha-amylase from Aspergillus niger (SEQ ID NO: 3) was compared with the structure of Novamyl 1QHO, and variants were constructed by altering the sequence SEQ ID NO: 3 as follows:
Q35K
Q35R
P70K
L151F
L151D
N233G+G234D
D75G
D75A
166-171 (EGDTIV) substituted with FTDPAGF (Novamyl loop (long))
Example 3
Construction of Variants of Fungal Amylase from T. lanuginosus
A three-dimensional model of SEQ ID NO: 4 (fungal amylase from T. lanuginosus ) was constructed from a model of SEQ ID NO: 2 (fungal amylase from A. oryzae ) using the alignment shown in FIG. 1 . Residues were selected, and variants were constructed with amino acid alterations to substitute or delete selected residues as follows:
G35K
G35R
A76del+D77del
D74del+A78del
D74A
D74G
D77A
D77G
Y157W
L168F+A169T+T171P+P172A+T173G
Example 4
Anti-Staling Effect of Variants (Straight-Dough Method)
Baking tests were made with the following variants of SEQ ID NO: 2 (fungal amylase from A. oryzae ):
Alteration in SEQ ID NO: 2 (fungal amylase)
168-171 (DNTV) substituted with DPAGF
Y75A
Q35R
Q35R + Y75F
168-171 (DNTV) substituted with DPAGC
L232Y
168-171 (DNTV) substituted with DPAGF + Y75A
D233G + G234D
168-171 (DNTV) substituted with DPAGF + Q35K + Y75A
Doughs were made according to the straight dough method. Bread was baked in lidded pans, and the bread was stored at ambient temperature. Firmness and elasticity were evaluated after 1, 4 and 6 days. Each variant was added at a dosage of 1 mg per kg flour. Controls were made without enzyme, with the parent fungal amylase of SEQ ID NO: 2 and with Novamyl (maltogenic alpha-amylase of SEQ ID NO: 1).
The results showed that the fungal alpha-amylase variants and Novamyl improved the elasticity after storage compared to the control without enzyme, whereas the fungal alpha-amylase gave a slightly lower elasticity. All the enzymes tested (variants, fungal amylase and Novamyl) improved the firmness after storage. In conclusion, the amino acid alterations succeeded in changing the functional properties of the fungal amylase to make it more Novamyl-like.
Example 5
Anti-Staling Effect of Variants (Sponge-and-Dough Method)
Baking tests were made with the following variants of SEQ ID NO: 2 (fungal amylase from A. oryzae ):
Alteration in SEQ ID NO: 2 (fungal amylase)
168-171 (DNTV) substituted with DPAGF
Y75A
Doughs were made by the sponge & dough method, and the variants were tested as in the preceding example. Controls were made without enzyme, with the parent fungal amylase of SEQ ID NO: 2 and with Novamyl (maltogenic alpha-amylase of SEQ ID NO: 1).
The variants show comparable softness and improved elasticity relative to the parent amylase, when dosed at optimal dosage in this trial.
A sensory evaluation by a small panel agrees with NMR data on mobility of free water and shows that the variants improve the moistness of bread crumb to the same level or slightly better than the parent amylase.
In conclusion, the variants showed improved effect (a more Novamyl-like effect) compared to the parent amylase.
Example 6
Exo/Endo Ratio of A. oryzae Amylase variants
The following variants of SEQ ID NO: 2 (fungal amylase from A. oryzae ) were tested:
Alteration in SEQ ID NO: 2
168-171 (DNTV) substituted with DPAGF
Y75A
168-171 (DNTV) substituted with DPAGC
Q35R
Q35R + Y75F
The exo- and endo-amylase activities were determined for each variant by the assays described in the specification, and the parent amylase was tested for comparison. The results showed that each variant had a higher degree of exo-amylase activity (higher exo/endo-amylase ratio) that the parent fungal amylase.
Example 7
Exo/Endo Ratio of A. niger Amylase Variants
The following variants of SEQ ID NO: 3 (acid amylase from A. niger ) were tested:
Alteration in SEQ ID NO: 3
D75G
Q35K
L151F
L151D
N233G + G234D
The exo- and endo-amylase activities were determined for each variant by the assays described in the specification, and the parent amylase was tested for comparison. The results showed that each variant had a higher degree of exo-amylase activity (higher exo/endo-amylase ratio) that the parent fungal amylase. | The inventors have developed a method of altering the amino acid sequence of a fungal alpha-amylase to obtain variants, and they have used the method to construct such variants. The variants may be useful for anti-staling in baked products. Accordingly, the invention provides a method of constructing fungal alpha-amylase variants based on a comparison of three-dimensional (3D) structures of the fungal alpha-amylase and a maltogenic alpha-amylase. One or both models includes a substrate. The invention also provides novel fungal alpha-amylase variants. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C. § 119(e), of provisional application No. 60/858,288 filed Nov. 9, 2006 and of German application No. DE 10 2006 053 202.3-45, filed on Nov. 9, 2006; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention pertains to a pipeline configuration for the transport of a liquid, wherein the liquid, especially petroleum, is transported in a pipeline laid above ground.
[0003] The occurrence of leakage in pipelines that are laid above ground, such as those carrying petroleum, can result in substantial environmental damage.
[0004] In order to be able to identify even small leaks as soon as possible and also ascertain their location, it is therefore known, for example, from published, non-prosecuted German patent application DE 43 34 550 A1, to lay a sensor mechanism beneath such a pipeline—in the 6 o'clock position—to make possible a detection of the product fluid escaping from the pipeline and at the same time measure the location of the leak. In this known device, an angle profile is placed underneath the pipeline, serving as a catchment gutter for the fluid escaping from the pipeline in event of a leak, and in which the sensor mechanism is placed, being an electrical sensor cable in the known device.
[0005] A sensor mechanism or sensor line suitable for use on such pipelines is known, for example, from European patent EP 0 175 219 B1 (corresponding to U.S. Pat. No. 4,735,095) and is formed of a carrier pipe, which is provided with a permeable layer on its outer surface, through which a substance escaping from a leak in the pipeline into the surroundings of the sensor line and being detected can diffuse. The carrier pipe is impermeable to this substance. Its wall is provided with openings so that the substance passing through the permeable layer can get into the interior of the sensor line through these openings. Such a sensor line is also known as a collector line. With a method familiar from German patent DE 24 31 907 C3 (corresponding to U.S. Pat. No. 3,977,233), the place at which the substance has made its way into the sensor line is then determined. This place corresponds to the site at which the substance has escaped from the pipeline being monitored. In this known method, using a pump hooked up to the sensor line, the substance which has penetrated into the sensor line along with a carrier gas present in the sensor line is taken to a data recorder, likewise hooked up to the sensor line, with which the substance contained in the carrier gas can be detected. If the flow rate is known, the time interval between turn-on of the pump and arrival of the substance at the data recorder can be used to determine the place at which the substance is getting into the sensor line and, thus, the site of the leak on the pipeline.
[0006] As an alternative or a supplement to the above mentioned permeable sensor line carrying a carrier gas (collection line) for the detecting and locating of leaks in pipelines, it is known, for example, from published, non-prosecuted German patent applications DE 195 35 399 A1 or DE 101 16 496 A1, how to use a light guide as the sensor line, whose transmission properties are altered locally, either directly by the substance escaping from the pipeline or by a heat of reaction produced in its surroundings as the substance escapes.
[0007] However, in the monitoring of leaks on pipelines laid above ground, especially pipelines in regions where strong winds often occur, it has proven to be a problem that the liquid emerging from the pipeline and flowing downward along its outer circumference, especially in the case of small volumes, cannot be detected with adequate certainty with a sensor line laid underneath the pipeline.
BRIEF SUMMARY OF THE INVENTION
[0008] It is accordingly an object of the invention to provide a pipeline configuration for the transport of a liquid, especially petroleum that overcomes the above-mentioned disadvantages of the prior art devices of this general type, which is a pipeline laid above ground with a sensor line disposed beneath the latter, wherein the detection of a leak at a distance from the sensor line is improved, even when leakage volume is small.
[0009] With the foregoing and other objects in view there is provided, in accordance with the invention, a pipeline configuration for transporting a liquid, including petroleum. The pipeline configuration contains a pipeline laid above ground and has an outer surface and a longitudinal direction. A catchment container is fixed to the pipeline and extends along the pipeline. The catchment container has edges running in the longitudinal direction with a given spacing from the outer surface of the pipeline. A device is disposed inside the catchment container for reducing an air flow moving between the catchment container and the outer surface of the pipeline transversely to the longitudinal direction. A sensor line for detecting leaks is disposed beneath the pipeline and extends along the pipeline in the longitudinal direction. The sensor line is disposed in the catchment container at a lowest point of the catchment container.
[0010] According to these features, a sensor line is disposed beneath the pipeline for detection of a leak, extending along the pipeline in its longitudinal direction and disposed in a catchment container, fixed to the pipeline and likewise extending along it, at its lowest point, and whose side edges running in the longitudinal direction have a spacing from the outer surface of the pipeline.
[0011] The invention is based on the understanding that the problems in detecting slight leakage volumes escaping from the pipeline outside of the 6 o'clock position are due primarily to the fact that the liquid flowing downward along the outer surface of the pipeline drips off from the pipeline before it reaches the sensor line laid underneath the pipeline in the 6 o'clock position and wets it.
[0012] Thanks to the use of a catchment container, in which the sensor line is disposed and which extends along the pipeline, with its side edges running in the longitudinal direction having a spacing from the outer wall of the pipeline, the liquid detaching itself from the outer surface of the pipeline drips into the catchment container and flows in this to its lowest point, where the sensor line is situated.
[0013] The dimensions of the catchment container transverse to the longitudinal direction of the pipeline are basically dictated by the physical properties of the outer surface of the pipeline and the liquid being detected, i.e., its flow and adhesion properties, which determine the detachment position for the liquid flowing downward on the surface of the pipeline.
[0014] The distance of the side edges of the catchment container from the outer surface of the pipeline must also be adapted to the physical properties of pipeline and liquid, in order to make sure that the liquid flowing along the outer surface of the pipeline flows into the space formed between pipeline and catchment container and does not drip off from the edge.
[0015] Thus, thanks to the measures of the invention, the liquid escaping from the pipeline during a leak outside of the 6 o'clock position makes contact with the sensor line and therefore can be reliably detected, even with low leakage rates.
[0016] Since, furthermore, a device is provided within the catchment container to reduce the air flow moving between the catchment container and the outer surface of the pipeline transversely to its longitudinal direction, it is possible to detect leaks which occur during strong wind at the side of the pipeline away from the wind (leeward), since in any case a much reduced air flow can occur along the underside of the pipeline. A pronounced air flow within the catchment container, transversely to the longitudinal direction of the pipe, would in fact result in the point of detachment or the edge of detachment being driven by the air flowing out from the catchment container between the leeward edge and the pipeline into a zone lying outside of the catchment container, during strong cross winds occurring at the leeward edge. Suitable as such devices are all structural measures which lessen the flow resistance for a crosswise current occurring inside the catchment container, for example, deflection vanes extending into the interior of the catchment container, being spaced apart in the lengthwise direction and staggered relative to each other in the transverse direction. In other words: flow obstacles disposed inside the catchment container, configured and disposed such that they do not hinder the transport of the fluid escaping during the leak to the lowest point of the catchment container.
[0017] In one advantageous embodiment of the invention, a channel to accommodate the sensor line is provided in the catchment container, extending in the longitudinal direction. This makes possible a definite positioning of the sensor line inside the catchment container.
[0018] In particular, the channel has generally vertically running sidewalls, which are provided with openings, and it divides the catchment container into two zones disposed symmetrically to the vertical midplane of the pipeline, which lead the liquid occurring during a leak from the pipeline to the channel, so that it gets into the sensor line through the openings. The sidewalls create a high flow resistance transversely to the longitudinal direction, which significantly reduces the size of a transverse flow in the space between catchment container and pipeline.
[0019] An especially high flow resistance is achieved when the channel lies against the pipeline. For this, in an especially preferred embodiment of the invention, a sealing element is inserted between a base of the channel and the outer surface of the pipeline, extending in the longitudinal direction of the pipeline.
[0020] If the catchment container is fastened to the pipeline by a clamping band embracing the latter, which is preferably led through recesses located in the sidewalls of the channel, a simple and secure retrofitted mounting of the catchment container on an already present pipeline is possible.
[0021] In an especially preferred embodiment of the invention, the channel is formed by a u-shaped molding, open at the bottom, in the catchment container, which is closed by a bottom piece at its lower end, which is fixed to the catchment container by a locking connection. Thanks to this measure it is possible, in a first installation step, to mount the catchment container, not yet closed by the bottom piece, on the pipeline before the sensor line has been introduced into the channel if the clamping band is led through the catchment container at a distance from the lower opening in the catchment container that is greater than the diameter of the sensor line. After the catchment container has been mounted, the sensor line can then be inserted from below into the channel, and it is then closed by simple pressing on and locking of the bottom piece, so that the sensor line lies definitively in the channel.
[0022] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0023] Although the invention is illustrated and described herein as embodied in a pipeline configuration for the transport of a liquid, especially petroleum, 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.
[0024] 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 SEVERAL VIEWS OF THE DRAWING
[0025] FIG. 1 is a basic schematic diagram of a pipeline configuration according to the invention;
[0026] FIG. 2 is a diagrammatic, sectional view of the pipeline configuration according to the invention in a final installed condition, where a catchment container is fixed to a pipeline; and
[0027] FIG. 3 is a diagrammatic, perspective view of the catchment container before being mounted on the pipeline.
DETAILED DESCRIPTION OF THE INVENTION
[0028] Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a pipeline configuration for the transport of a liquid O and contains a pipeline 2 , on whose underside a sensor line 6 is disposed in the 6 o'clock position, that is, in a midplane 4 running vertically and parallel to a longitudinal direction of the pipeline 2 , i.e., perpendicular to the plane of the drawing. The sensor line 6 is disposed inside a catchment container 8 , disposed on the pipeline 2 and approximately v-shaped in cross section, and the sensor line 6 is situated there at its lowest point. Between side edges or margins 10 of the catchment container 8 , extending in a longitudinal direction of the pipeline 2 , and an outer surface 12 of the pipeline there is a gap 14 , through which the liquid O emerging upon leakage and flowing along the outer surface 12 , in this example, petroleum, can flow into the catchment container 8 .
[0029] FIG. 1 illustrates a situation in which the liquid O emerging upon leakage at a leak site L arrives at the outer surface 12 of the pipeline 2 , being located in an upper region of the pipeline 2 within the 6 o'clock position. Starting from the leakage site L, the liquid O now flows downward on the outer surface 12 by the action of gravity, whereupon the gravity exerted on the liquid is directed away from the outer surface after reaching the 3 o'clock position. Depending on the viscosity and adhesion properties of the liquid O, it runs along the outer surface 12 up to a drip point D, until the adhesion forces are no longer enough to hold the liquid O on the outer surface 12 . At this point, the liquid O drips off from the outer surface 12 and arrives in the catchment container 8 , as illustrated in FIG. 1 , in which it then runs down to the lowest point at the 6 o'clock position and wets the sensor line 6 .
[0030] The transverse dimensions of the catchment container 8 , i.e., an angle range α through which the catchment container 8 extends by its edge 10 , depends on the physical properties of the liquid O and the outer surface 12 of the pipeline 2 and is dimensioned so as to assure that the drip point D is located within the angle range α.
[0031] In FIGS. 2 and 3 one notices that the catchment container 8 is constructed from an approximately v-shaped profile 15 , having two legs 16 oriented at a slant to each other, which extend opposite each other, each starting from an approximately vertically oriented side wall 18 (in the final installed condition) of a channel 20 approximately u-shaped in cross section, formed between them, in mirror symmetry to the midplane 4 . The legs 16 are tilted to the sidewalls 18 and make an acute angle with them, so that the u-shaped channel 20 is situated inside the v-shaped profile 15 formed by the legs 16 .
[0032] A base 22 of the u-shaped channel 20 is provided with a molding that projects into it, in which an elastic sealing element 24 is inserted in the final installed condition, by which the base 22 of the channel 20 lies tightly against the outer surface 12 of the pipeline 2 ( FIG. 2 ).
[0033] Per FIGS. 2 and 3 , the channel 20 divides the catchment container 8 into two zones disposed symmetrically with respect to the vertical midplane 4 , which convey the liquid O escaping from the pipeline 2 during a leak to the sensor line 6 . The sidewalls 18 of the channel 20 are provided with openings 26 for this, though which the liquid O running down along the inside of the legs 16 gets into the interior of the channel 20 .
[0034] In the final installed condition ( FIG. 2 ), the channel 20 is closed at its lower end by a likewise v-shaped bottom piece 30 , so that the liquid O getting into it through the openings 26 cannot escape downward.
[0035] The striplike bottom piece 30 shown in FIG. 3 in a condition prior to the final installation is provided with elastic locking elements 32 disposed symmetrically to the midplane 4 , each of which engage by their locking dogs 34 with a shoulder or projection 36 formed in the sidewalls 18 and fix the bottom piece 30 to the catchment container 8 by form fitting and close off the channel 20 at its lower end. The locking elements 32 are ties formed from the bottom piece 30 , which produce a locking or snap connection with the channel 20 . Instead of a projection 36 extending in the longitudinal direction of the sidewalls 18 , one can also provide projections spaced apart from each other or openings spaced apart from each other in the sidewalls 18 , being disposed at the same spacing as the locking elements 32 .
[0036] The sidewalls 18 of the channel 20 are provided with a recess 40 at given intervals, through which a clamping band 42 can be led, which reaches under the base 22 and embraces the pipeline 2 so that the catchment container 8 is fixed onto it. In order to enable an easier introducing of the clamping band 42 into the recess 40 , the base 22 is interrupted in the region of the recess 40 , so that the clamping band 42 can be led beneath a L-shaped projection 46 sticking out beyond the side recess 40 .
[0037] A plurality of ties 50 are formed from the legs 16 , standing vertically on the legs 16 , pointing into the interior of the profile 15 , and serving as spacers from the outer surface 12 of the pipeline 2 .
[0038] The installation of the catchment container 8 is done in that first the sealing element 24 , such as a sealing compound or an elastic sealing tape, is introduced into the depression formed by the molding of the base 22 . Next, the profile 15 is mounted on the pipeline 2 in the 6 o'clock position, the clamping band 42 is introduced into the recess 46 and the profile 15 is fixed to the pipeline 2 . In this stage of the installation, the channel 20 is open at its lower end. The sensor line 6 is now introduced into this channel 20 from underneath, it being preferably a sensor line such as is known, for example, from the initially cited European patent EP 0 175 219. After installing the sensor line 6 , the channel 20 is closed with the bottom piece 30 .
[0039] The sidewalls 18 of the channel 20 , the sealing element 24 serving generally only to even out irregularities in the outer surface 12 of the pipeline 2 , and the sensor line 6 laid inside the channel 20 have the effect that an air flow A impacting the pipeline 2 from the side does not move through the catchment container 8 , but instead moves past its lower end, as is illustrated in FIG. 2 at left. The occurrence of such a cross flow inside the catchment container 8 is significantly reduced, since the openings 26 disposed at the lowest point of the catchment container 8 , which are in any case small, and the recesses 40 made only at rather large intervals do not allow for a pronounced cross flow. Furthermore, such a cross flow is also hindered by the sensor line 6 disposed in the channel 20 . In this way, the drip point D on the leeward side is prevented from wandering outward, so that the liquid O running off at the leeward side of the outer surface 12 drips into the catchment container 8 even during strong cross winds. | A pipeline configuration for the transport of a liquid, especially petroleum, contains a pipeline laid above ground, beneath which is disposed a sensor line for detection of a leak, extending along the pipeline in its longitudinal direction. The sensor line is disposed in a catchment container, fixed to the pipeline and likewise extending along it, at its lowest point. The catchment container has side edges running in the longitudinal direction and have a spacing from the outer surface of the pipeline. Inside the catchment container a device is disposed to reduce an air flow moving between the catchment container and the outer surface of the pipeline transversely to its longitudinal direction. | 6 |
FIELD OF THE INVENTION
The invention relates to check valves, and in particular to valves used to prevent backflow through a fluid-conducting passage.
BACKGROUND OF THE INVENTION
Particularly in the plumbing and waterworks industries, situations frequently arise where it is important to ensure that a fluid flows through a conduit in only one direction. Such a result is often achieved by introducing a check valve into the conduit. Check valves utilize any of a variety of valve mechanisms, including balls, flaps, swing doors, and poppets to allow fluids to flow in one direction, but not the other.
One exemplary situation in which uni-directional flow is desirable is in residential water supply applications. In such applications, it is preferable to allow water to flow only from the water main into the residence, and not vice versa. This is because should water flow from the residence to the water main (which can occur when there is a pressure drop in the water main caused by, for example, a broken water main or burst fire hydrant), the municipal water supply can be contaminated. Traditionally, residential water supply applications have not included check valves. However, in view of increasing concerns about the safety of municipal water supplies, a demand has arisen among municipalities to retrofit existing residential water supply plumbing to install check valves therein.
Many existing check valves however have been found to be unsuitable for use in such retrofits for various reasons. For example, many existing check valves are simply too long or are otherwise too large to fit in the available space. Others utilize valve mechanisms which do not allow for sufficient flow rates thereby unacceptably reducing residential water pressure. Other valves have too many moving parts or parts which can fall out of the valves during handling, resulting in difficulties during installation. Finally, many check valves are simply not suitable for situations where neither of the connections between which the valve is to be mounted, is rotatable, as may be the case when inserting a check valve between a water meter and a supply line in a retrofitting application.
Poppet-style valves are particularly advantageous for such applications because they tend to be simple, durable, reliable and compact. Typically, poppet-style valves consist of one or more sealed valve units contained within a sleeve. Such valve units have a first and a second end and include a poppet, a disk having a guidepost extending perpendicularly from its center, reciprocally slidable axially within the valve unit. The poppet has a sealing surface which can seat against an annular surface at the first end of the valve unit. The poppet is biased towards the first end such that its sealing surface seats against the annular surface when no flow exists through the valve unit. When the fluid pressure at the second end of the valve unit is greater than that at the first end, this pressure differential tends to hold the poppet tightly against the annular surface thereby increasing the sealing force. When the fluid pressure at the first end exceeds the fluid pressure at the second end by an amount sufficient to overcome the biasing of the poppet towards the annular surface, the poppet moves away from the annular surface allowing for fluid flow through the valve unit from the first end to the second end. The sleeve has connections at either end to allow the valve to be mounted in-line in a conduit.
Despite its advantages, poppet-style valves have only seen limited use in residential water supply retrofit applications. This is because conventional designs result in valves having limited flow rates, valves which are often too large for retrofitting applications, and valves which are difficult to service in the field.
SUMMARY OF THE INVENTION
In a broad aspect, the present invention provides a poppet-style check valve comprising: a valve body having a bore therethrough and having an upstream inlet end, a downstream outlet end, an interior surface, and an exterior surface; inlet connection means for connecting said inlet end of said valve body to a fluid supply; outlet connection means for connecting said outlet end of said valve body to a fluid outlet; a valve seat located within said valve body, said valve seat having a valve seat surface defining a bore therethrough; a poppet having a face parallel to the valve seat surface, and a stem substantially perpendicular to said face, said poppet face being sized and shaped to be capable of covering the bore defined by the valve seat surface; a poppet support for receiving said stem of said poppet for reciprocal movement therein between a first position in which the face of the poppet is held against the valve seat surface and a second position in which the poppet face is spaced from the valve seat surface; sealing means for preventing flow through the check valve when the poppet is in its first position; flow means for permitting flow through the check valve when the poppet is in its second position; poppet control means for moving the poppet between its first position and its second position in response to changes in a differential between fluid pressure at the inlet end and fluid pressure at the outlet end of the valve body; wherein said flow means for permitting flow through the check valve when the poppet is in its second position comprises at least one flow passage through each of the valve seat, the valve seat surface, and the poppet support, at least one flow passage around the poppet face, and an expansion of the valve body bore around the poppet face; wherein the flow passage around the poppet face when the poppet is in its second position, is defined by a periphery of the poppet face and the valve body.
Other aspects of the invention include the above check valve wherein:
the poppet support locks into place within the valve body once it is inserted into the valve body during assembly of the check valve;
the poppet support is inserted through the inlet end of the valve body during assembly of the check valve, and locks into place within the valve body by means of upstream facing teeth along a periphery of the poppet support engaging an annular poppet support locking recess on the interior surface of the valve body;
the poppet support is further locked into place within the valve body by means of a downstream-facing surface of the poppet support abutting an upstream-facing poppet support shoulder on the interior surface of the valve body;
the valve seat locks into place within the valve body once it is inserted into the valve body during assembly of the check valve;
the valve seat is inserted through the inlet end of the valve body during assembly of the check valve, and locks into place within the valve body by means of upstream facing teeth along a periphery of the valve seat engaging an annular valve seat locking recess on the interior surface of the valve body;
the valve seat is further locked into place within the valve body by means of a downstream-facing surface of the valve seat abutting an upstream-facing valve seat shoulder on the interior surface of the valve body;
the valve seat is an annular sleeve, the at least one flow passage through the valve seat is a bore defined by the annular sleeve, and the valve seat surface is a downstream end of the annular sleeve;
the valve seat is located within the valve body upstream of the expansion of the valve body bore;
the poppet support has a poppet guide sleeve for receiving the poppet stem, an annular support rim for connecting the poppet support to the interior surface of the valve body, and connecting means for connecting the poppet guide sleeve to the support rim;
the connecting means is a plurality of spokes extending from the poppet guide sleeve to the support rim, spaces between the spokes comprising the at least one flow passage through the poppet support;
exactly three spokes extend from the poppet guide sleeve to the support rim;
the support rim is located within the valve body downstream of the expansion of the valve body bore, and the poppet guide extends upstream from a plane defined by the support rim;
the poppet is located intermediate the valve seat and the poppet support within the valve body, and the poppet stem extends downstream from the poppet face;
the poppet includes an annular poppet seal associated with the poppet face, and the sealing means for preventing flow through the check valve when the poppet is in its first position includes a seal created between the poppet seal and the valve seat surface when the poppet is in its first position;
the poppet seal is held within an annular poppet seal recess on the periphery of the poppet face, said poppet seal recess being defined by an upstream portion of the poppet face, a poppet sleeve extending downstream from the upstream portion of the poppet face, and an annular seal-retention flange extending radially outwardly from the poppet sleeve;
both the poppet seal and the seal-retention flange extend radially outwardly beyond a periphery of the upstream portion of the poppet face such that when the poppet is in its first position, the upstream portion of the poppet face fits within the valve seat surface, the poppet seal contacts the valve seat surface, and the seal-retention flange supports the poppet seal against the valve seat surface;
an upstream surface of the poppet face has a central protrusion to direct fluid flowing downstream through the check valve toward the periphery of the poppet face;
biasing means are provided for biasing the poppet towards its first position;
the poppet control means for moving the poppet between its first position and its second position in response to changes in a differential between fluid pressure at the inlet end and fluid pressure at the outlet end of the valve body comprises the biasing means, as well as upstream and downstream surfaces of the poppet face being substantially perpendicular to a direction of flow through the check valve which causes a force to be exerted on the poppet when a pressure differential exists between the inlet and outlet ends of the valve body, said poppet moving from its first position to its second position when the force exerted on the upstream surface of the poppet face by a higher fluid pressure at the inlet end of the valve body is sufficient to overcome a force exerted by the biasing means, and the poppet moving from its second position to its first position otherwise;
said biasing means is a spring located between the poppet and the poppet support;
the valve seat has an annular valve seat seal mounted within an annular seal recess on a periphery of the valve seat, said sealing means for preventing flow through the check valve when the poppet is in its first position including a fluid seal created by the valve seat seal between the valve seat and the valve body;
the inlet connection means comprises a threaded female connector sealably and rotatably mounted on the inlet end of the valve body; and/or
the outlet connection means comprises external threading on the outlet end of the valve body.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will now be described with reference to the attached drawings in which:
FIG. 1 is a perspective view of the check valve in accordance with a preferred embodiment of the present invention;
FIG. 2 is a perspective exploded view of the check valve;
FIG. 3 is a perspective view of a valve cartridge of the check valve;
FIG. 4 is a cross-sectional side view of the check valve in a closed position;
FIG. 5 is a cross-sectional side view of the check valve in an open position;
FIG. 6 is a cross-sectional side view of a valve body of the check valve;
FIG. 7 is a cross-sectional side view of an inlet connection nut of the check valve;
FIG. 8 is an end view of a valve seat of the check valve;
FIG. 9 is a cross-sectional side view of the valve seat;
FIG. 10 is a cross-sectional side view of a poppet of the check valve;
FIG. 11 is an end view of a poppet support of the check valve;
FIG. 12 is a side view of the poppet support; and
FIG. 13 is a cross-sectional side view of a further embodiment of the present invention without the inlet connection nut.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the check valve of the present invention will now be described in the context of an exemplary application of retrofitting a residential water supply system to inhibit backflow from a residence to a water main.
In a typical residential water supply system, water from a municipal water main is conveyed to an interior wall of the residence through an underground pipe. A water meter which tracks water use by the residence for billing purposes is mounted to this pipe at the residential end. A supply pipe then conveys the water from the water meter to the various outlets within the residence.
When retrofitting such a residential water supply system to install a check valve, the valve is normally installed between the water meter and the supply pipe. Most typically, the female threaded connector of the supply pipe is disengaged from the male threaded connector of the water meter, the check valve is placed between the two, and the water meter and supply pipe are each connected to each end of the check valve. The check valve is oriented such that it permits flow from the water meter to the supply pipe, but not from the supply pipe to the water meter.
The preferred embodiment check valve 10 is illustrated in FIGS. 1 through 12 . FIGS. 1 , 4 and 5 show the check valve 10 in its assembled state while FIG. 2 is an exploded view of the check valve 10 , showing its constituent parts. Broadly, the check valve 10 consists of a valve body 12 , a valve cartridge 14 (as shown in its assembled form in FIG. 3 ) located within the valve body 12 , and an inlet connection nut 16 attached to an inlet end of the valve body 12 . Each of these broad elements will now be discussed in turn.
In this description and in the claims, the terms “axial” and “axially” are used to describe a direction parallel to a centerline of the check valve 10 , while “radial” and “radially” are used to describe a direction perpendicular to and extending from the centerline of the check valve 10 . Further, “downstream” is used to describe features which are located nearer an outlet end 13 of the check valve 10 , while “upstream” is used to describe features which are located nearer an inlet end 11 of the check valve 10 .
The valve body 12 , shown in detail in FIG. 6 , has an inner bore 17 therethrough, and consists of an upstream inlet section 18 , a downstream outlet section 20 , and an expanded section 22 intermediate the inlet and outlet sections 18 , 20 .
An exterior surface of the inlet section 18 is provided with an annular retaining ring recess 24 to accommodate a retaining ring 26 , as discussed further below. An interior surface of the inlet section 18 is provided with an annular valve seat locking recess 28 near an upstream end of the valve body 12 , and an annular valve seat shoulder 32 near an interface between the inlet section 18 and the expanded section 22 . The valve seat locking recess 28 and the valve seat shoulder 32 cooperate to lock a valve seat 34 into its proper position within the valve body 12 , as discussed further below.
The inner bore 17 of the expanded section 22 of the valve body 12 has a diameter greater than that for either the inlet section 18 or the outlet section 20 . This greater diameter accommodates the flow of fluid through the expanded section 22 around a poppet 36 of the valve cartridge 14 as discussed further below. An exterior surface of the expanded section 22 is provided with two faceted annular protrusions 38 facilitating engagement of the valve body 12 by a tool such as a wrench when threadedly connecting the check valve 10 with the supply pipe. An interior surface of an interface between the expanded section 22 and the outlet section 20 is provided with an annular poppet support locking recess 40 and an annular poppet support shoulder 42 which cooperate to lock a poppet support 44 into its proper position within the valve body 12 , as discussed further below.
The outlet section 20 of the valve body 12 is provided on its exterior surface with exterior threading 46 to accommodate connection with the female threaded connector of the supply pipe (not shown).
The valve cartridge 14 , shown in FIG. 3 , consists of the poppet 36 , a poppet seal 47 , the poppet support 44 , a spring 48 interposed between the poppet 36 and the poppet support 44 , and the valve seat 34 .
The poppet 36 , as shown in detail in FIG. 10 has a disc-shaped poppet face 50 , with a poppet stem 52 extending downstream from the center thereof. The poppet face 50 has an upstream-facing central protrusion 54 to direct downstream-flowing fluid towards the periphery of the poppet face 50 when the check valve 10 is in its open position. Extending downstream from an upstream portion of the poppet face 50 , coaxial with, and surrounding a portion of the poppet stem 52 , is an annular spring-retention sleeve 56 . The spring-retention sleeve 56 is spaced from the poppet stem 52 so as to accommodate both the poppet support 44 and the spring 48 . Extending radially outwardly from the spring-retention sleeve 56 is an annular seal-retention flange 58 . The seal-retention flange 58 is spaced downstream from the upstream portion of the poppet face 50 so as to accommodate the annular poppet seal 47 therebetween. The diameter of the upstream portion of the poppet face 50 is less than the diameter of the seal-retention flange 58 so as to allow the poppet seal 47 to be slipped over the upstream portion of the poppet face 50 and into the space between the upstream portion of the poppet face 50 and the seal-retention flange 58 during assembly of the check valve 10 . Additionally, this differential in the outer diameters of the upstream portion of the poppet face 50 and the seal-retention flange 58 allows the poppet seal 47 to contact the valve seat 34 , and also allows the seal-retention flange 58 to support the poppet seal 47 against the valve seat 34 .
The poppet support 44 , as seen in detail in FIGS. 11 and 12 , includes a poppet guide 60 , a sleeve whose purpose is to guide reciprocal axial movement of the poppet 36 . The inner diameter of the poppet guide 60 is slightly larger than an outer diameter of the poppet stem 52 such that there exists a close fit between the two parts when the poppet stem 52 is inserted into the poppet guide 60 . The outer diameter of the poppet guide 60 is sized so as to be spaced radially inwardly from the annular spring-retention sleeve 56 when the check valve 10 is in its open position, so as to accommodate the spring 48 therebetween. A downstream portion of the poppet guide 60 has support spokes 62 extending radially outwardly therefrom, said spokes connecting the poppet guide 60 with a support rim 64 . The support spokes 62 are fin-like, having a narrow profile when viewed from a downstream end. Further, the number of support spokes 62 is kept low. Preferably, only three support spokes 62 are provided. The narrow profile of the support spokes 62 as well as the low number of support spokes 62 maximizes the cross-sectional flow area of the poppet support 44 . The support rim 64 is annular and is adapted to be locked in position on an interior surface of the valve body 12 at the interface between the expanded section 22 and the outlet section 20 . In particular, a downstream portion of the support rim 64 is adapted to abut against the poppet support shoulder 42 of the valve body 12 while a plurality of poppet support locking protrusions or teeth 66 are adapted to be secured within the poppet support locking recess 40 of the valve body 12 . The poppet support locking protrusions 66 are spaced circumferentially around an outer surface of the support rim 64 and have a steep upstream face 68 and a sloped downstream face 70 such that the poppet support 44 can be slid into the valve body from its upstream end, and locked into place. The combination of the support rim 64 and the support spokes 62 serves to maintain the poppet guide 60 positioned centrally within the valve body 12 , and co-axial therewith.
The valve seat 34 , as shown in detail in FIGS. 8 and 9 , is an annular sleeve adapted to be locked into place within the inlet section 18 of the valve body 12 . Near its upstream end, an outer surface of the valve seat 34 is provided with a plurality of valve seat locking protrusions or teeth 72 adapted to be secured within the valve seat locking recess 28 of the valve body 12 . The valve seat locking protrusions 72 are spaced circumferentially around the outer surface of the valve seat 34 and have a steep upstream face 74 and a sloped downstream face 76 such that the valve seat 34 can be slid into the valve body 12 from its upstream end, and locked into place. The outer surface of the valve seat 34 is also provided with an annular shoulder 78 adapted to abut against the valve seat shoulder 32 of the valve body 12 when the valve seat 34 is locked into place within the valve body 12 . Still on the outer surface of the valve seat 34 , an annular O-ring recess 80 is provided upstream of the shoulder 78 . The O-ring recess is adapted to support and retain a valve seat O-ring 82 . A downstream end of the valve seat 34 provides an annular valve seat surface 84 against which the poppet seal 47 is pressed when the check valve 10 is in its closed position. The valve seat surface 84 has an inner diameter greater than the outer diameter of the upstream portion of the poppet face 50 .
By eliminating a conventional lining wall (not shown) within the valve body 12 in the region surrounding the poppet 36 , the flow area around the poppet 36 can be maximized, while the external diameter of the check valve 10 can be minimized.
The inlet connection nut 16 has a downstream section 86 and an upstream section 88 . An inner surface of the downstream section 86 is sized to fit closely over the outer surface of the inlet portion 18 of the valve body 12 , and is provided with an annular retaining ring recess 90 adapted to receive the retaining ring 26 . An outer surface of the downstream section 86 is provided with facetted tool-engaging surfaces 92 to allow the inlet connection nut 16 to be engaged by a tool for turning purposes. The upstream section 88 is provided with internal threading 94 to accommodate a threaded connection with the male threaded connector of the water meter (not shown). A gasket 96 is provided within the inlet connection nut 16 near an interface between the downstream section 86 and the upstream section 88 . The internal threading 94 and the gasket 96 serve to provide a sealed connection between the check valve 10 and the water meter.
An exemplary manner in which the preferred embodiment check valve 10 may be assembled will now be described.
First, the poppet seal 47 is pushed over the upstream portion of the poppet face 50 and into the annular space between the upstream portion of the poppet face 50 and the seal-retention flange 58 . Similarly, the valve seat O-ring 82 is placed into the O-ring recess of the valve seat 34 .
Second, the poppet support 44 is slid in through the upstream end of the valve body 12 with its poppet guide 60 facing upstream, until the downstream surface of the support rim 64 abuts against the poppet support shoulder 42 of the valve body 12 , and the poppet support locking protrusions 66 engage the poppet support locking recess 40 . The resilient flexibility of the support rim 64 and the sloped downstream face 70 of the poppet support locking protrusions 66 cooperate to allow the poppet support locking protrusions 66 to be pushed radially inwardly while the poppet support 44 is being pushed into its locked position, while the steep upstream face 68 of the poppet support locking protrusions 66 serve to lock the poppet support 44 in place within the valve body 12 .
Next, the spring 48 is placed over the poppet guide 60 and the poppet 36 is inserted into the valve body 12 with the poppet stem 52 sliding into the poppet guide 60 and the spring-retention sleeve 56 sliding over the spring 48 .
The valve seat 34 is then pushed into the valve body 12 with its valve seat surface 84 facing downstream, until the valve seat 34 locks into place with its shoulder 78 abutting the valve seat shoulder 32 of the valve body 12 , and the valve seat locking protrusions 72 engaging the valve seat locking recess 28 . The resilient flexibility of the valve seat 34 and the sloped downstream face 76 of the valve seat locking protrusions 72 cooperate to allow the valve seat locking protrusions 72 to be pushed radially inwardly while the valve seat 34 is being pushed into its locked position, while the steep upstream face 74 of the valve seat locking protrusions 72 serve to lock the valve seat 34 in place within the valve body 12 .
Finally, the retaining ring 26 is placed into the retaining ring recess 24 of the valve body 12 , the inlet connection nut 16 is pushed onto the upstream end of the valve body 12 until the retaining ring 26 engages the retaining ring recess 90 of the inlet connection nut 16 , and the gasket 96 is inserted into the inlet connection nut 16 until it abuts the upstream end of the valve body 12 . The split-ring structure of the retaining ring 26 allows it to be expanded radially to fit over the upstream end of the valve body 12 while fitting the retaining ring 26 into the retaining ring recess 24 of the valve body 12 , and to also be compressed radially to allow the downstream end of the inlet connection nut 16 to be slid thereover. Once the retaining ring 26 is engaged within the retaining ring recesses 24 , 90 of both the valve body 12 and the inlet connection nut 16 , it resists axial movement of the inlet connection nut 16 away from the valve body 12 while allowing the inlet connection nut 16 to rotate relative to the valve body 12 to facilitate connection of the check valve 10 to the water meter.
Although an exemplary manner of assembling the check valve 10 has been described, it is to be understood that the check valve 10 may be assembled using other methods and in other sequences, as will be understood by those skilled in the art.
In use, the supply pipe of the residential water supply system is first disconnected from the water meter. The downstream end of the check valve 10 is then connected to the supply pipe by engaging the external threading 46 of the valve body 12 with internal threading of the female supply pipe connector. To facilitate tightening of the connection, a torquing tool such as a wrench may be used to engage the annular protrusions 38 of the valve body 12 .
Next, the inlet connection nut 16 is connected to the water meter by engaging the internal threading 94 of the inlet connection nut 16 with external threading of the male water supply connector. The retainer ring 26 connection between the inlet connection nut 16 and the valve body 12 allows the inlet connection nut 16 to be turned relatively to the valve body 12 to facilitate the threaded connection between the inlet connection nut 16 and the water meter. Again, to facilitate tightening of the connection, a torquing tool may be used to engage the faceted tool-engaging surfaces 92 of the inlet connection nut 16 . The gasket 96 ensures a sealed connection between the valve body 12 and the water meter.
When the pressure at the downstream and upstream ends of the check valve 10 are equalized, or when the pressure differential is small, the spring 48 pushes the poppet 36 upstream such that the poppet seal 47 is pressed against the valve seat surface 84 of the valve seat 34 , as shown in FIG. 4 . In this state, the check valve is closed, and flow through the check valve is restricted.
If the water pressure at the downstream end of the check valve 10 exceeds the pressure at the upstream end, this pressure differential tends to increase the force with which the poppet 36 is pressed against the valve seat 34 , thereby improving the seal between the poppet seal 47 and the valve seat surface 84 .
If the water pressure at the upstream end of the check valve 10 exceeds the pressure at the downstream end by a degree sufficient to overcome the spring force exerted by the spring 48 , then the increased pressure of the water against the poppet face 50 moves the poppet 36 downstream away from the valve seat 34 allowing water to flow from the upstream end of the check valve 10 to the downstream end, as shown in FIG. 5 . In this open state, the large central bore of the valve body 12 , valve seat 34 , the large cross-section openings of the poppet support 44 and the expanded internal diameter of the expanded section 22 of the valve body 12 all serve to maximize the rate at which water can flow through the check valve 10 and to thereby minimize the water pressure drop through the check valve.
In applications where the prevention of backflow through the valve is particularly important, redundant valve systems are frequently used. FIG. 13 illustrates a second embodiment 100 of the present invention (without the inlet connection nut 16 ) in which the valve cartridge contains two valve seat 34 /poppet 36 /poppet support 44 combinations. In this figure, like elements are identified using the same reference numbers as used in describing the first embodiment, and the two instances of each element are differentiated using the suffixes “a” and “b”.
As is apparent from FIG. 13 , the second embodiment check valve 100 is substantially the same as the first embodiment check valve 10 , with a duplication of some features and the merging of other features. There are now two expanded sections 22 a , 22 b of the valve body 12 to accommodate the two valve systems. The first expanded section 22 a houses the first valve seat 34 a , the first poppet 36 a and the first poppet support 44 a , while the second expanded section 22 b houses the second valve seat 34 b , second poppet 36 b and the second poppet support 44 b . The second valve seat 34 b is combined with the first poppet support 44 a into a single element. Thus, the support rim 64 b of the first poppet support 44 a is merged into the features of the second valve seat 34 b.
The second embodiment check valve 100 therefore provides redundant protection, such that if one of the valve systems fails, the second will function to prevent backflow through the check valve 100 .
In both the preferred and second embodiment check valves 10 , 100 , the valve body 12 and inlet connection nut 16 are made of either brass or bronze, the valve seat 34 , poppet 36 and poppet support 44 of the valve cartridge 14 are made of plastic, and the seals and gaskets 47 , 82 , 96 are made of rubber. However, it is to be understood that other suitable materials may be used as will be appreciated by persons skilled in the art.
In the exemplary application described, the check valve is installed between a water meter and a residential supply pipe to prevent backflow of water from a residence to a water main. However, it is to be understood that the check valve of the present invention may be used in various other applications. For example, the check valve can be used in many plumbing or waterworks application to ensure uni-directional flow through a conduit. It can also be used to ensure uni-directional flow of other fluids, sewage or gasses for example.
Very specific geometries of the various elements have also been provided. However, it is to be understood that other suitable geometries may be used by persons skilled in the art without necessarily departing from the scope of the invention.
Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practised otherwise than as specifically described herein. | A poppet-style check valve for allowing uni-directional flow in a fluid conducting system. The check valve comprises a valve body, and a poppet mounted therein for reciprocal axial movement between a first position in which the poppet is pressed against a valve seat restricting flow through the check valve, and a second position in which the poppet is spaced from the valve seat permitting flow through the check valve. An inner bore of the valve body is expanded in the area of the poppet to maximize flow through the check valve, and the external dimensions of the check valve are minimized by eliminating a conventional liner between the poppet and the valve body. Additionally, the elements of the valve mechanism are designed such that they lock in place within the valve body during assembly. | 8 |
SUMMARY
The present invention provides a new structure and passenger transport paradigm for accommodating passengers in a vehicle with particular attention paid to safety, utility and provides new features for utility.
FIELD OF INVENTION
The present inventions provide a new structure and passenger transport paradigm for accommodating passengers in a vehicle with particular attention paid to safety, utility and comfort.
SUMMARY
The Drawings illustrate embodiments of the inventions. These features and more are described below. The invention relates to the referenced filed applications.
BRIEF DESCRIPTION OF DRAWINGS
5 - 1001 —Latch tension lever
5 - 1002 —Pivoted latch carrier assembly/housing (front facing and rear facing positions possible)
5 - 1009 —Aperture for rotating latch (to face up from rear facing to front facing and vise versa)
5 - 1019 —Cam Pin
5 - 1020 —Cam Thumb Nut
5 - 1021 —Cam assembly pulley
5 - 1022 —Cam Tension Bar Threaded for Cam Thumb Nut
5 - 1023 —Access hole for cable
5 - 1024 —Access slot for Pulley (alternate attachment of Latch cam assembly on this end of Tube
5 - 1025 —Pin
7 - 1007 —Frame assembly
7 - 1014 —Brace: Latch assembly to central pivot rod (part of latch tensioning assembly)
7 - 1015 —Recess for Latch tension assembly on frame body
7 - 1017 —hole on frame body for latch housing in front facing mode.
7 - 1018 —holes on foot rest/front brace for attaching latch housing for rear facing seat mode.
7 - 1022 —Aperture on latch carrier for securing in front/rear facing position (rod for securing not shown)
7 - 2000 —Main roller (support pin not shown)
7 - 2001 —secondary roller(s) (support pin(s) not shown)
7 - 2002 —deformable strip
7 - 2003 —Lower hook
7 - 2004 —Upper hook
7 - 2005 —body
7 - 2006 —Cut out on deformable strip (lower force for deformation)
7 - 2007 —Slot on First deformable strip
7 - 2008 —Pin hole (pin not shown) on Second deformable strip
7 - 2002 A—First deformable strip
7 - 2002 B—Second deformable strip
7 - 2009 —Cutter
7 - 2010 —Cuttable strip
7 - 2011 —Slots for cutter. Longer slots allow cut to begin after displacement of cutter (for second and higher levels of force)
7 - 2020 —Latch body for webbing strip adjustment
7 - 2021 —Webbing control Latch catch (pin support not shown, tension pulls towards retain wall on latch housing. Spring mounted for release)
7 - 2022 —Retain wall on Latch housing
7 - 2023 —lever for operating latch from front of seat
7 - 2024 —fastener aperture for fastening to Latch body
7 - 2025 —apertures for fastening on seat body
7 - 2026 —Insert for Car seat belt Latch
7 - 2027 —Latch for Car Seat Belt latch insert mounted on load limiter
8 - 1001 —Pivot tube (inserted into an option bushing on frame)
8 - 1002 —Latch tensioning assembly
8 - 1003 —Cable lead-in (Latch—not shown.)
8 - 1004 —aperture in pivot tube (the pivot tube may also be in two sections with a break between for the insertion of the cable)
8 - 1005 —optional support bush on latch tensioning assembly to support the pivot tube
8 - 1006 —Cable
9 - 2001 —Harness slots
9 - 2002 —Release catch
9 - 2003 Right half—Chest plate
9 - 2004 —Left half—Chestplate
9 - 2005 —chin support surface
9 - 2006 —access aperture of r catch on chest plate
9 - 2007 —Chin rest
9 - 2008 —Belt
9 - 2009 —crush pad—level 1
9 - 2010 —crush pad—level 2
10 - 1000 —Shoulder guard
10 - 1001 —Headrest
10 - 1002 —Headrest pivot support
10 - 1003 —Headrest pivot support link
10 - 1004 —Headrest Pivot support—forward pivot
10 - 1005 —Headrest Pivot support—rear pivot
10 - 1006 —Headrest support (attached to vertical movement mechanism or fixed to seat)
10 - 1007 —Attachment means to vertical movement mechanism or fixed seat.
10 - 1008 —Edge of shoulder plate—(engages notch on headrest Pivot support link)
10 - 1009 —side of shoulder plate
10 - 1010 —thorax guard
10 - 1011 —Shoulder slide backplane
10 - 1012 —Shoulder slider
10 - 1013 —shoulder slider slots for sliding
10 - 1014 —shoulder slide backplane—Pins for support of slider and sliding on slot
10 - 1015 —shoulder slide—actuating arm for headrest
10 - 1016 —Shoulder slide—actuating arm for headrest—slot
10 - 1017 —headrest attachment pivot for shoulder slide—actuating arm (pin not shown)
7 - 2000 —Main Roller
7 - 2002 —Deformable Strip
7 - 2003 —Lower Hook
7 - 2004 —Upper Hook
7 - 2005 —Body
7 - 2006 —Cutout on deformable strip
7 - 2012 —Sheath
7 - 2013 —pin
7 - 2014 —Side Roller
7 - 2015 —cutout for Lower hook
7 - 1016 —recess to allow the end stop as it moves along a trajectory attached to the end of the deformable strip towards the roller.
7 - 1017 —protrusion to lock the (slightly flexible) sheath to the tube on the hole on the tube
7 - 1018 —sides of recesses for the two legs of the deformable strip to keep the deformable strip in the middle of the roller.
12 - 001 —spool
12 - 002 —webbing
12 - 003 —fill tape
12 - 004 fill tape, webbing insert slot for securing on spool
12 - 005 retractor drum
12 - 006 —pin load limiters to spool
12 - 007 —pin load limiter A to retractor drum
12 - 008 —pin: load limiter B to retractor drum
12 - 009 —spring for retractor
12 - 010 —housing
12 - 011 —slot on retractor drum for delayed engagement of load limiter B
12 - 012 —slot for webbing connection (may be an open slot for threading a loop of webbing)
12 - 013 —spool with splined bearing surface for sliding tubular axle
12 - 014 —splines on spool
12 - 015 —sliding tubular axle with screw thread engaging the housing
12 - 016 —load limiter A′ has a slot for increasing and decreasing the active twist length.
12 - 017 —slot on load limiter A′
12 - 018 —Threads on the outer surface of sliding tubular axle
12 - 019 —graded height profile of fill tape.
12 - 020 —ratchet
12 - 021 —Spring loaded ratchet key
12 - 022 —Ratchet key secondary spring
12 - 023 —gong strike
12 - 024 —gongs (different frequencies for the two gongs signal position of key)
12 - 025 —aperture for connecting cable or webbing for control of ratchet key (a second cable may be connected on the far side of the pivot if locking and unlocking of the key are required by cables or webbing
12 - 026 —Apertures for supporting ratchet on retractor drum with pins on drum.
13 - 001 —Upper Unit/occupant support
13 - 002 —Lower unit/occupant support
13 - 003 —Base unit
13 - 004 seat track for support
13 - 010 —seat track
13 - 011 —latch body
13 - 012 —Latch pin
13 - 013 —Horizontal slider support
13 - 014 —Horizontal slider
13 - 015 —Horizontal spring damper
13 - 016 —Vertical slider with attachment for base unit or occupant support
13 - 017 —Lower vertical spring damper
13 - 018 —Upper vertical spring damper
13 - 019 —Aperture for pin holding units/occupant supports/bases
13 - 020 —pin hole to support horizontal slider support
10 - 1000 —Shoulder guard
10 - 1001 —Headrest
10 - 1002 —Headrest pivot support
10 - 1003 —Headrest pivot support link
10 - 1004 —Headrest Pivot support—forward pivot
10 - 1005 —Headrest Pivot support—rear pivot
10 - 1006 —Headrest support (attached to vertical movement mechanism or fixed to seat)
10 - 1007 —Attachment means to vertical movement mechanism or fixed seat.
10 - 1008 —Edge of shoulder plate—(engages notch on headrest Pivot support link)
10 - 1009 —side of shoulder plate
10 - 1010 —thorax guard
10 - 1011 —Shoulder slide backplane
10 - 1012 —Shoulder slider
10 - 1013 —shoulder slider slots for sliding
10 - 1014 —shoulder slide backplane—Pins for support of slider and sliding on slot
10 - 1015 —shoulder slide—actuating arm for headrest
10 - 1016 —Shoulder slide—actuating arm for headrest—slot
10 - 1017 —headrest attachment pivot for shoulder slide—actuating arm (pin not shown)
10 - 2001 —Pulley with Male protrusion that matches the female groove axial forces compress the protrusion against the groove to hold together Some embodiments use serrations on circular sections that are co axial to the form/pulley surfaces to increase the friction during axial loading.
10 - 2002 —Pulley with Female groove that matches the male protrusion axial forces compress the protrusion against the groove to hold together. Some embodiments use serrations on circular sections that are co axial to the form/pulley surfaces to increase the friction during axial loading.
14 - 001 —Seat back support
14 - 002 —seat bottom
14 - 002 A—seat bottom Sleeping position
14 - 002 B—seat bottom Sitting position
14 - 003 —Upper Sleeper enclosure/mini-cabin
14 - 004 —Lower Sleeper enclosure/mini-cabin
14 - 005 —support bins (with foot frame integrated on separate inside for structural support)
14 - 006 pop-up storage bins
14 - 006 A—pop-up storage bin—retracted provides the armrest or bed surface
14 - 007 —Screen or projector (for projection on table top)
14 - 008 —Mount for Oxygen mask (and generator if used in embodiment) and mount for screen or projector
14 - 009 —symbols for locking mechanisms between units.
14 - 010 —Steps for egress and ingress to upper sleeper
14 - 011 —Leg space covering protecting lower occupant
14 - 012 —Leg rest—center section
14 - 013 —rear wall for steps also is a shear plane bracing element for strengthening the support for the upper sleepers
14 - 014 —handles for egress ingress
14 - 015 —Bin Drawer open for accessing baggage. Some embodiments have belt at bottom to move luggage back and forward
14 - 016 —Profile of human occupant
14 - 017 —Shear “plane” (may not be flat) for bracing the lower sleeper for supporting the upper sleeper particularly under imp-act conditions.
14 - 018 —Ribs for bracing the side walls of the lower sleeper. Ribs are within the space under the arm rests and straddle the pop-up bins in some embodiments.
14 - 019 —Main actuator for some embodiments of changing the incline of the seat back and seat bottom. In some embodiments, the same actuator with limit switches can be used for pushing out the leg rest that slides under the seat bottom. The lower force and higher displacement requirements for the leg rest retraction and deployment can be achieved with suitable gearing or levers well disclosed in the background art.
14 - 020 —Seat pan
14 - 021 —Side element of leg rest attached to the seat bottom
14 - 022 —step above the sleep position seat bottom and leg rest are positioned at end of sleeper to avoid conflict with upper passenger egress and ingress
14 - 023 —cutout on the lower sleeper flange (and in some embodiments the leg rest side element) allows a comfortable foot position on the bottom step for the upper passenger for egress ingress.
14 - 024 —bottom step for egress and ingress of upper passenger
14 - 025 —enclosure for bracing ribs for lower sleeper enclosure (bracing ribs not shown) can be on both sides of the lower sleeper enclosure.
14 - 026 —Bracing ribs
14 - 027 —seat back anchor
14 - 027 A—seat back anchor Sleeping position
14 - 027 B—seat back anchor Sitting position
14 - 028 —Seat mechanism Support Pan
14 - 029 —Slider (or roller) slot for seat bottom front support on Seat Pan (slide or roller on seat bottom front end. The slot profile can change the angle of the sitting position and all positions of recline as the seat bottom moves about the pivot at the rear end.
14 - 030 —Seat slider or roller (2 positions shown for sitting and sleeping positions
14 - 031 —Pivot of the seat back anchor on seat pan
14 - 032 A—Pivot of seat anchor on seat bottom rear end in the sleeping position
14 - 0328 —Pivot of seat anchor on seat bottom rear end in the sitting position
14 - 033 —Actuator pivot support on support Pan
14 - 034 —Actuator body (other embodiments may be rotational actuators attached to rotate about either of the pivots noted
14 - 035 —Actuator shaft. Alternative embodiments may have limit switches activated when the seat bottom gets to the sleeping position and thereafter the head of the actuator is locked to the leg support that can be pushed out. Variable gearing or lever arrangements for displacement force ratios are well disclosed in the background art.
14 - 036 —Leg Rest side sections attached to seat bottom
14 - 037 —Slot in Seat bottom for sliding leg rest center section that can be retracted under the seat bottom when in the sitting position and deployed for the full sleeping surface when the seat bottom is normally (but even other positions) in the sleeping position.
14 - 038 —Bottom Bin with structural support integrated or attached thereto to support the AirSleeper occupant supports. Attached to the floor or tracks of the aircraft cabin.
14 - 039 —Belt for moving baggage
14 - 040 —Rollers/pulleys for guiding the belt
14 - 041 secondary rollers for supporting belt with load. Alternative embodiments will have a low friction surface between the two surfaces of the belt between the pulleys. Still other embodiments may simply have a low friction inside surface of the belt so that the upper and lower sections slide easily on each other.
15 - 2000 —Main roller
15 - 2002 —deformable strip
15 - 2003 —Lower hook may be fabricated from bent sheet metal
15 - 2004 —Upper hook
15 - 2005 —body tube
15 - 2006 —Cut out on deformable strip (lower force for deformation)
15 - 2010 —Support Pin
15 - 2011 —lower webbing attachment slot
15 - 2012 —recessed lip for strip support
15 - 2013 —Assembly wedge
15 - 2014 —pin for webbing attachment (may have head and cotter pin at ends to secure)
15 - 2015 —aperture for pin for webbing attachment
15 - 2016 —body channel section (instead of tube as in eg 2005 )
15 - 3000 —headrest
15 - 3001 —shoulder guard
15 - 3002 —links
15 - 3003 —slot attachment on shoulder guard to attach to headrest pivot
15 - 3004 —head rest pivot axle
15 - 3005 —belt slots on adjustable height seat backplane
15 - 3006 —recess on headrest for should guard slider engagement
15 - 3007 —Slide guides on seat height adjustment backplane
15 - 3008 —slides in shoulder guard
15 - 3009 —slots for support rivets/bolts/sliding attachment means between shoulder guard slide and height adjustment backplane
15 - 3010 —Link pivots on headrest
15 - 3011 —link attachments on height adjustment backplane.
16 - 1000 —Seat Bottom
16 - 1001 —Leg rest base
16 - 1002 —Leg rest Slider
16 - 1003 —Main Slider
16 - 1004 —Side Slider
16 - 1005 —Pusher rod 1
16 - 1006 —Pusher rod 2
16 - 1007 optional front flange on leg rest slider
16 - 1008 —Lock on leg rest to the leg rest slider
16 - 1009 —Lock on Seat bottom to the main slider
16 - 1010 —Actuator body
16 - 1011 —Actuator shaft
16 - 1012 —Seat Back in flat bed position
16 - 1013 —Seat Back in sit up position
16 - 1014 —Pivot of Seat Back on support member of AirSleeper
16 - 1015 —Pivot between Seat Back and Seat Bottom
16 - 1016 —Seat Bottom in flat bed position (seat bottom in sit up position not shown)
16 - 1017 —Pivotal attachment between Actuator shaft and Main slider
16 - 1018 —Pivotal attachment between Actuator body and support member of AirSleeper
FIGS. 1-01, 02, 03 and 03A represent different views of the latch tension assembly. FIG. 1-04 to 1-12 show different embodiments of load limiters for occupant supports. In addition FIG. 1-05 incorporates a latch for the tension webbing of the child seat harness. FIG. 1-12 also is a chin support attached to the harness. Either or both the chin support function and the load limiting function can be incorporated I the device on FIG. 1-12 .
FIGS. 2-01 to 2-04 c show an embodiment of a headrest actuated by a shoulder guard to move to ensconce the head during a lateral impact thereby protecting the head.
FIG. 2-01 shows two view of a headrest actuated by a shoulder guard. In the centered or normal position the shoulder guard is fixed to the headrest and the assembly is attached with links to the shell. FIG. 2-02 shows the same arrangement with the right shoulder of the child pushing the shoulder guard outwards resulting in the headrest moving around the head. The movement is usually spring loaded to return to the centered position. It may also have a disconnect member at a pre-determined load.
FIG. 2-03 shows another design of the invention where the headrest continues to be attached to the links however the shoulder guard and the thorax guard (one of the shoulder guard and the thorax guard are needed. Alternatively another support on the side of the body can be used) are on slides for lateral sliding they are engaged together with an actuating arm.
FIG. 2-03A shows the same arrangement as FIG. 2-03 without the Thorax Guard.
FIG. 2-04A shows different views of the Headrest/shoulder guard/thorax guard assembly in the centered position.
FIG. 2-04B shows the same assembly as 1 - 04 A in the displaced position with the actuation of the headrest by the shoulder guard/thorax guard.
FIG. 2-04C shows the overlaid centered position of the shoulder guard and thorax guard on the assembly as in FIG. 2-04B to show movement.
FIGS. 2-05 to 2-07 show a load limiting module for the front impact for a child seat or for the use as a module on a seat belt of a car. In particular the design is adapted for a manufacturing process and assembly process is a part of this invention.
FIG. 2-05 shows the assembled load limiting module.
FIG. 2-06 shows the exploded view particularly with a view to show the process for assembly which is part of this invention.
FIG. 2-07 shows different views of the sheath
FIGS. 3-01, 02 and 03 show different views of the headrest and shoulder guard mechanism. These figures show additional aspects of the invention that illustrate provisions for intrusion loading of the mechanism during side impact.
FIGS. 3-04, 05, 06 and 07 show different levels of assembly of a mechanism for supporting the load of the harness during front impact while preventing excess load on the external edge of the webbing and preventing the “bunching up” of the webbing towards the center end of the slot leading the webbing from the front of the seat to the back of the seat.
FIG. 4-01 is a cross section of an embodiment of the adaptive load-limiter/retractor.
FIG. 4-02 Shows a surface mounted embodiment of the adaptive load limiter/retractor (autolock sprocket and mechanism is not shown) This may be used in a vehicle for the seat belt or on a CRS.
FIG. 4-03 is a exploded view of the adaptive load-limiter/retractor
FIG. 4-04 show the webbing and fill tape wound on the spool.
FIG. 4-05 shows a webbing mounted embodiment of the adaptive load-limiter/retractor
FIG. 4-06 shows the different radii of the moment of the force from the load limiter at the axis of the spool as the webbing unwinds
FIG. 4-07 Shows another embodiment of the adaptive load-limiter/retractor where the load limiter force is varied by changing its effective length, here with a thread on the spool shaft that moves the sliding tubular axle in or out depending on the how much the spool has turned and therefore how much webbing has been dispensed.
FIG. 4-08 Shows another embodiment of the fill tape with a variable cross section to control the moments of the force from the load limiter at different lengths of dispensed webbing.
FIGS. 4-09 and 4-10 shows the additional machinery for an embodiment of a ratchet mechanism for locking the retractor while in use. This load limiting function is separate from the ratchet retractor mechanism and other retractor mechanisms may be used with the adaptive load limiter.
AirSleeper Certification
FIG. 5-01 to 5-05 show different embodiments of modular occupant supports in a vehicle.
FIG. 5-01 shows a modular system of occupant supports where there is a single upper occupant support supported by two lower occupant supports.
FIG. 5-01A shows the same modular system of FIG. 5-01 but where the impact loading is at an angle α To the orientation of the tracks.
FIG. 5-02 shows a modular system of occupant supports where there are two upper occupant supports supported by three lower occupant supports.
FIG. 5-03 shows a modular system of occupant supports where there are three upper occupant supports supported by four lower occupant supports.
FIG. 5-04 shows a modular system of occupant supports where there are four upper occupant supports supported by five lower occupant supports.
FIG. 5-05 shows a long array of occupant support along the axis of a vehicle.
FIG. 5-06 , FIG. 5-07 shows different views of a Latch mechanism for the array of occupant supports with shock absorption devices with spring dampers (only springs shown)
FIG. 5-08 to 5-36 show results for the empirical simulation validation of the method of this invention.
FIG. 5-37 is a table of Lumbar Loadings for inclined orientation.
FIG. 5-38 to 5-44 show the different configurations in the simulations both at the start of the frame sequence and during the impact event.
FIGS. 5-38 to 5-45 show the arrangement in the simulations at time −0 and during impact.
FIG. 5-46 shows the load supported by a lower unit in the tiered configurations of FIG. 5-01 to 5-05 .
FIG. 5-47 —shows views of a side guard for a child seat
FIG. 5-48,5-49 —shows parts of the side guard modified to accommodate different shoulder (or thorax) widths. It has serrations or notches that allow the ends to be secured in different positions relative to the center.
FIG. 5-50 shows the tapered form for leading the harness over the support bar, while providing a profile that does not allow it the harness to ride up towards the center of the seat.
FIG. 5-51 shows the same form that is either slidably or pivotally attached to the bar—in a version that is field installable by having two interlocking halves that are designed to stay together during an axial load as in a impact situation where the harness is under tension.
FIGS. 6-01 to 6-05 , Show an array of AirSleeper occupant supports in a vehicle—in particular an aircraft.
FIG. 6-06 to 6-10 show a single lower AirSleeper occupant support unit
FIG. 6-11 Shows an upper Air Sleeper occupant support unit.
FIGS. 6-12 to 6-13 Show an embodiment of the actuation mechanism and motion of the seats for multiple positions between sit up and lay flat.
FIG. 6-14 shows the retraction of the center section of the leg rest in one of the embodiments. The Leg rest may also retract with an angular displacement about the rear edge and attached to the seat bottom in other embodiments.
FIG. 6-15 shows the bottom storage bin that has either integrated or attached support features with an option al drawer and optional belt
FIGS. 6-16 and 6-17 show an alternative architecture for the actuation of the seat back and bottom.
The seat bottom here moves forward when in the sitting position.
FIG. 7-01 to FIG. 7-04,04A, 04B show several embodiments for a load limited that may be used on either the harness (as shown) or for the tether (with end attachments modified). FIG. 4, 4A, 4B show variations in the housing structure using channel sections tubing and bent material. They also show different securing means for the lower webbing section.
FIG. 7-05 , FIG. 7-06 side hard for pro-active head support in side impact with actuating shoulder guard with seat headrest height adjustment backplane shown in FIG. 7-05 but not in FIG. 7-06 . Both have the headrest actuated to an angled position with the shoulder guard which has been moved laterally with the inertial load of the shoulder and thorax.
FIG. 7-07, 08 show the Headrest and the shoulder guard with headrest height adjustment backplane removed. The links are pivotally connected to this and the shoulder guard is slid ably connected to this.
FIG. 7-07 shows the actuated position (laterally displaced shoulder guard and rotated headrest) FIG. 7-08 shows the normal position.
FIG. 8-01 to 8-04, 03A shows the seat bottom mechanism for using a single actuator to change the angle of the seat bottom by displacing a point on the seat bottom relative to a moving pivot attached to the seat back in many embodiments; moving forward a sliding leg rest; and sliding side ways a leg rest wing and an optional leg rest extension.
FIG. 8-05 to 8-08 show AirSleeper modules where the steps for egress and ingress to the upper Air Sleeper module are recessed thereby providing greater aisle space particularly at shoulder level. Other aspects are that the steps have a grade that is ergonomically attractive. Finally the steps are positioned to have minimal effect on the lower occupant space in the lower Air Sleeper enclosure or mini-cabin.
DETAILED DESCRIPTION OF INVENTION
CRS Embodiments
The LATCH or ISOFIX tensioning mechanism has a cable (or other flexible attachment) 8 - 1006 between the two LATCHs or ISOFIX attachments. This cable is passed through the support arrangement—the latch carrier 5 - 1002 for the LATCH/ISOFIX head and through the pivot axis on the pivot tube 8 - 1001 to the latch tensioning assembly 8 - 1002 , where it is tensioned first for rough tensioning with the Cam Thumb nut 8 - 1020 and for fine tension on a normal basis with the Latch Tension Lever 5 - 1001 .
The Latch carrier has an aperture 5 - 1009 that allows the removal of the latch and rotation of the latch about the axis of the Latch Carrier so that the same latch can be used right side up for front facing mode and rear facing mode of the latch carrier. The Latch carrier is pivoted on the Pivot tube that may be supported on the outer side of the latch carrier or on both sides of the Latch carrier by the seat structure. This may be a thin flange that is on the outside of the Latch carrier and in some embodiments also on the inside of the latch carrier and besides the Latch tensioning assembly 8 - 1002 . The Seat Frame (support structure of the seat) 7 - 1007 has a recess on the bottom 7 - 1015 to accommodate a rear facing or front facing orientation of the Latch Carrier 5 - 1002 . The Latch Carrier is locked for the Front facing seat position with the aperture 7 - 1022 to the aperture on the seat frame 7 - 1017 and in the rear facing mode for the seat with the aperture on the Foot rest 7 - 1018 . There are multiple inclinations possible with the multiple holes 7 - 1018 . A rod or pair of rods secure the 7 - 1022 in either position.
The Latch Carrier 5 - 1002 has a cable lead in 8 - 1003 to support the cable as it curves through 90 degrees into the Pivot tube 8 - 1001 .
The Pivot tube may have a slot on its side to accommodate the cable 8 - 1004 or be split in two parts. If a split structure is used the outer part need not be a tube but can be a rod.
The Pivot tube supports the cable up to the inner opening of the Tensioning assembly as shown in FIG. 1-02 .
Both the tensioning Assembly and the Latch carrier may have bushes that strengthen them for the support of the Pivot tube 8 - 1001 .
The Tensioning assembly 8 - 1002 has a tensioning mechanism that pulls (or pushes) the cable away from it natural axis between the two pivot tubes, thereby tensioning the cable 8 - 1006 . The cable goes over a pulley 5 - 1021 (or a pin) which is secured to a Cam Tension Bar 5 - 1022 that goes through a section of the main body of the tensioning assembly 8 - 1002 , through an aperture at the front and then through an aperture in the Cam pin 5 - 1019 , and then ha its threaded end attached to the threads of the Cam Thumb Nut 5 - 1020 . The Cam Pin 5 - 1019 is inserted in to the Latch tension Lever 5 - 1001 ahead of the insertion of the 5 - 1022 . The Latch Tension Lever 5 - 1001 is contoured at its contact surface with the body of the Tension assembly to have an increasing distance from the central axis of the Cam Pin 5 - 1019 to the surface of the Body of the Tensioning assembly, thereby moving the cam pin 5 - 1019 away from the body of the Tensioning assembly, thereby pulling the Cam tension bar and the attached pulley and in turn pulling the cable thereby tensioning the cable.
It may be seen from the FIG. 1-03 that the Latch tension Lever has a slot to accommodate the cam nut end and the Cam tension Bar as the lever is raised and depressed.
Load Limiters that May be Used with the Harness and Tether in CRS.
FIG. 1-04 to FIG. 1-12 show several embodiments for a load limited that may be used on either the harness (as shown), for the tether (with end attachments modified), for the attachment point for the tether on the vehicle, or as an attachment to the car seat belt latch attachment specifically tuned for the needs of children in boosters or child seats, or specially custom tuned for occupants as an after market product that can be inserted into any car seat belt latch point.
This class of load limiters are designed to have controllable force displacement characteristics by bending strips of material, cutting materials such as metal or compressing blocks of materials such as compressible foams with known crush characteristics. Notably each of the load limiters disclosed may have multiple load levels that are activated sequentially as the load progresses over time protect occupants of different masses.
With regard to the bendable strips, The width and thickness of the strips at different points along their length of displacement will determine the force at that point of displacement. The principal application in the CRS is to have constant forces over a given displacement which may be achieved with a constant cross section for the strip for that length. However, it may be desired to have multiple “plateau”s of constant force to cater for different loads on the CRS. This can be done with multiple cross sections along the length of the strip.
For example in FIG. 1-04, 05, 08, 09, 10 we have a cut out on the strip that changes the cross section for part of the length. When this section is bent it will show a lower force whereas when the full section is bent it will have a larger constant force.
One issue that needs to be overcome for a lower initial force plateau and a higher force plateau later, is the problem that the smaller cross section needs to pull the wider cross section through the process of bending. If the differences in cross section are large the narrow section will begin to extend substantially in preference to bending the wider cross section. The solution in FIGS. 1-06 and 1-07 among other benefits, addresses this problem by having two separate strips. This embodiment will be described later.
The embodiments shown bent the strip over a roller (although a low friction rod may be used) the angle over which it is bent may be varied. Also the strip may be supported on the side before bending by a retaining structure as in the body 7 - 2005 of the load limiters.
For the load limiters that bend strips, one of the attachment points for the harness or the tether is to the end of the strip 7 - 2002 . The roller is pivotally attached to the housing or body 7 - 2005 which attached to the second attachment point. Notably the first and second attachment points can be the attachment points to the harness tensioning webbing section and the two harness sections that go to the front of the child seat below the child.
FIGS. 1-04, 05, 08, 09 show versions with a cut out on the strip that will reduce the force between the attachment points as the reduced section 7 - 2006 of the strip is bent around the main roller. The force will rise when the full section reaches the main roller. Any of the embodiments shown can have this reduced section feature. Moreover the reduced section feature can have a variable section to have a varying force.
FIGS. 1-06 and 1-07 use two strips for two “plateaus of force. The First deformable strip 7 - 2002 A has a slot in it 7 - 2007 which engages a pin attached to a hole 7 - 2008 on the second strip. When there is tension applied between the upper and lower hooks, the first strip bends over the roller as the pin slides through the slot 7 - 2007 . When the pin 7 - 2008 reaches the end of the slot the second strip is also pulled along and therefore its cross section is also bent and therefore the force rises to the second plateau.
In the embodiments shown in both FIGS. 1-06 and 1-07 , the first strip 7 - 2002 A is bent over the second strip 7 - 200 B. The second strip deforms first and there is marginal force on the first strip 7 - 2002 A. Once the end of the slot is reached the first strip 7 - 2002 A is also pulled and the aggregate force increases. Multiple strips can be used for this for multiple force plateaus.
In FIG. 1-06 The pin hole and the slot are indexed and a pin (not shown) holds them together. In FIG. 1-07 the same pin is used to also hold the Upper hook 7 - 2004 for cost economies and compact architectures.
FIG. 1-05 shows any of the load limiter architectures with bending or cutting strips compression of material, extension of materials as disclosed herein and in prior disclosures, for use in child seats, wherein the body of the load limiter 7 - 2005 is attached to the bottom of the seat ahead of the opening customarily used for the harness adjustment latch. This embodiment includes a harness adjusting latch 7 - 2020 and obviates the need for a separate latch. The harness is threaded through an aperture in the front of the seat below the child as usual and enters the latch body 7 - 2020 . It is held against the body with a spring loaded webbing control latch catch 7 - 2021 which is pushed against the rise in the body—the retaining wall 7 - 2022 upon tension of the harness during impact and thereby locks the harness. Adjustment of the harness length but the user is effected by pulling the lever 7 - 2023 that acts against the spring loaded latch catch 7 - 2021 to allow movement of the harness support webbing in either direction for correct adjustment. Upon release of the lever the spring loading of h 7 - 2021 pushes the webbing against the retain wall 7 - 2022 of the latch housing and prevents tension on the harness from releasing the control webbing. FIG. 1-05 shows a bent strip version of the load limiter. FIG. 1-08 uses multiple rollers 7 - 2000 , 7 - 2001 (or pins) for bending the strip. The width of the slots may be adjusted at different distances along the strip to synchronize the force of bending on each roller as the strip reaches it. If a fixed width slot is used on 7 - 2002 the force will progressively increase as each roller encounters the strip without the slot for the first time.
To reduce the distance between the load points of the load limiter, the support points may be changed as in FIG. 1-09 where the support on the body lies close to the front hook. This can be used for any of the load limiter architectures ie using bending strips cutting strips extending or compressing materials as in this disclosure and prior disclosures. Such architectures will help negotiate curves on the supporting structure of the seat.
FIG. 1-10 shows an architecture of any of the strip bending or cutting material extending or compressing versions that can be installed to a vehicle seat belt assembly by the user. The 7 - 2026 —Insert for Car seat belt Latch is clicked into the car seatbelt latch and on the other side of the load limiter there is a cavity and latch 7 - 2027 —Latch for Car Seat Belt latch insert mounted on load limiter that accepted the car seat belt insert attached to the loop of the belt. The load limiter may be tuned for children in boosters or for child seats and indeed customized for occupants of any mass. Moreover, it can be tuned for the stiffness of the car to optimize protection with the load limiter. Moreover, it can be tuned for the stiffness of the car to optimize protection with the load limiter.
FIG. 1-11 , shows an embodiment that cuts a strip of material (usually metal. The slots 7 - 2011 of different lengths allow the cutting edges to meet the ends of the slots at different times thereby allowing multiple plateaus of force.
FIG. 1-12 , shows a load limiter that is on the front of the harness. This may in some embodiments be a part of the chin support disclosed. However it may be a stand alone load limiter separate for each of the sides of the harness or combined together with a chest clip type lock to hold them together.
FIG. 1-12 shows the harness threaded through the chest plate (separate left and right or split with a latch holding them together)
The harness is threaded through the slots in the chest plate 9 - 2 - 003 , 9 - 2004 and is routed over the crush pads 9 - 2009 and 9 - 2010 and are then threaded through the lower slots 9 - 2001 on the chest plate oleft and right sections.
The (optional) cover or chin support surface covers the assembly. It may be split with a latch between the sides or attach onto one or both of the chest plate left and right sections.
The Crush pads—level 1 9 - 2009 and Crush pads Level 2— 9 - 2010 are tuned to have crush parameters that provide plateaus of force required for 2 different masses of children. (multiple crush pad levels can be used for multiple levels of child masses) The thicknesses are chosen to give the required level of crush during the peak loadings that need to be mitigated.
The headrest/shoulder guard/thorax guard assembly is designed to protect the head in particular during a side impact or for that matter fast lateral acceleration. The simpler embodiment in FIG. 2-01, 02 has the shoulder guard attached to the headrest. The actuation of the shoulder guard sideways by the shoulder will pull the headrest along with it. The linkage arrangement that comprises the two headrest pivot support 10 - 1002 attached to the links 10 - 1003 which are pivotally attached to seat shell through the headrest support 10 - 1006 which may be a part of the mechanism for raising and lowering the headrest. The shoulder guard is attached to the headrest.
The links are angled as shown in the figures and therefore as the headrest moves laterally it is forces to rotate thereby ensconcing the head. This is seen in FIG. 2-02
FIG. 2-03, 03A are variations of another embodiment that has the shoulder guard 10 - 1000 and thorax guard 10 - 1010 in this embodiment (alternative embodiments may have any protrusion that can be pushed by the child's body sideways upon impact) that are attached with slides to the rear of the shell or the headrest mechanism for raising and lowering the headrest and harness support.
Leaf springs supported the shell or support point indirectly attached to the shell are attached to the headrest or the shoulder guard to return them to the centered normal position. Such assemblies are well disclosed in the background art. In this embodiment the same actuation of the headrest occurs as in the previous embodiment of FIGS. 2-01 and 02 However the actuation of the headrest is done with an actuation pivot 10 - 1017 attached to the headrest and with a pin that slides in a slot 10 - 1016 on the shoulder slide—actuating arm 10 - 1015 which is attached to the shoulder slider 10 - 1012 . This particular slider uses a slots 10 - 1013 sliding on pins 10 - 1014 attached to the shoulder slide back plane 10 - 1011 which is attached directly or indirectly to the shell.
FIGS. 2-04A, 04B and 04C show different positions of the shoulder guard/thorax guard and the actuation of the headrest as a result.
The Shoulder slide has a actuating arm 10 - 1015 that has a slot 10 - 1016 that is pivotally and slidably attached to the pivot 10 - 1017 on the headrest. The lateral movement of shoulder guard 10 - 1000 or the thorax guard 10 - 1010 force the slider 10 - 1012 laterally resulting in the actuating arm 10 - 1015 moving laterally. This pushes the headrest attachment pivot sideways thereby enabling the movement as shown of the headrest which ensconces the head. The slot 10 - 1016 on the actuator arm accommodates the change in the distance from the pivot on the headrest and the actuator arm changes as the headrest reorients and rotates.
The sliding arrangement of the shoulder slider can use any sliding arrangement disclosed in the background art. The slider may also be spring loaded to return to the centered position using spring arrangements well disclosed in the background art.
The load limiting module shown in FIG. 2-05 is used to limit peak loadings on the harness of a child seat or other occupant support to reduce injury. The embodiment shown has a deformable strip that is pulled over a roller when the force on the Upper hook exceeds a threshold thereby limiting the load.
The assembly of the embodiment shown in FIG. 2-05 is illustrated with the exploded view of FIG. 2-07 .
1. An end stop rivet or other protrusion (not shown) is attached to the small hole at the end of the deformable strip 7 - 2002 . This protrudes inwards within the deformable strip and engages the roller after the strip bends and slides through the body with impact force. 2. The Deformable strip 7 - 2002 is inserted into the Body 7 - 2005 so that the end of the bent section aligns with the lateral hole on the body 7 - 2005 . 3. The side holes on the Lower Hook 7 - 1003 is aligned with the hole on the body. 4. The side rollers 7 - 2014 are designed to be take the load of the pin 7 - 2013 supported by the sides of the hole on the body 7 - 2005 and the lower hook 7 - 2004 . The main roller 7 - 2000 is designed to facilitate the bending and movement of the deformable strip. The assembly of the side rollers the main roller all supported on the pin is pushed through the aligned holes on the body and the lower hook. 5. The sheath 7 - 1012 slides over the body and (optionally) locks with a protrusion on the hole on the top of the body. Finally the top hook is riveted to the deformable strip.
Several variations of the process are possible such as the use of a reduced form of the lower hook with topological equivalents that is simply a “U” channel with holes on the side flanges and where the webbing is passed over the center section of the U channel or topological equivalents.
The Lower hook can be removed completely and a slot on the body can be used to attach the webbing.
FIG. 2-07 shows some of the features of the sheath I a preferred embodiment. 7 - 2015 shows a recess that supports the ends of the pin and the side rollers and prevents them from falling out.
Several features are shown. The recesses 7 - 2018 will support the deformable strip at the center of the body to avoid skewing of the deformable strip as it is pulled over the roller. A recess 7 - 2016 allows the end stop (rivet) to move through the body as the deformable strip is pulled through, to finally engage the roller to stop further movement.
Notably the invention does not need the rollers, but can simply have the strip rolling over the pin with sliding friction.
The operation of the headrest actuating mechanism has been disclosed in a prior application and this disclosure provides additional aspects of this mechanism.
FIG. 3-01 shows the mechanism for actuating the headrest using the sliding shoulder guard. This embodiment in addition has a folding shoulder guard that folds in upon intrusion forces from the outside. The fig is depicts the position following a side impact left side and following intrusion that folds in the shoulder guard. Note in the shoulder guard the protruding lip of the rear section of the shoulder guard that will engage the front flap of the shoulder guard so that inertial loading resulting from the shoulder on impact will push it out.
The FIG. also shows the position of the two links after the inertial loading on the shoulder guard actuates the headrest. The link on the near side relative to the impact as seen is approximately orthogonal to the headrest support on the seat shell or mechanism for raising and lowering the headrest and harness attachments and shoulder guards in this embodiment, while the link on the far side lies flat or close to the support. In the event of intrusion forces on the headrest, the headrest is forced inwards and therefore pivots on the near side link and pushes the far side link further towards lying flat with the support thereby locking the links from returning to the normal position which necessitates the far side link rising up away from the support. This will ensure that the head is protected by the headrest that ensconces the head.
FIG. 3-02 shows the mechanism for actuating the headrest to protect the head as in FIG. 3-01 here the ratchet mechanism has two ratchet keys (pawls), one on each side spring loaded to contact the surface of the ratchet teeth on the static backplane of the shoulder guard slider mechanism (directly or indirectly with the mechanism for raising and lowering the seat, attached to the seat) that is spring loaded to touch the ratchet teeth. Notably the ratchet key on the side of the impact and inertial movement of the shoulder guard and shoulder slider will engage upon movement in that direction while the ratchet on the far side will simply slide over the ratchet teeth because of the inclination of the teeth surfaces and the inclination of the ratchet teeth. The pawls are enabled to rest on a flat surface without teeth in the center section under normal conditions and are therefore not able to engage any of the saw tooth sections.
The Ratchet will prevent the slider from sliding back following the intrusion force or external force thereby preventing the shoulder guard from moving back to the normal position in the event of intrusion thereby protecting the child and also preventing the headrest from being actuated back to the normal position.
FIG. 3-03 also shows the backward rotation of the far side link upon intrusion forces pushing the headrest in and thereby forcing it to pivot about the nearside link. This ensured that the guard ensconces the head. It also shows the folding shoulder guard upon intrusion forces pushing it in. Moreover the ratchet with teeth engaging on the impact side (Left side for the child).
FIG. 3-04 , FIG. 3-05 shows a mechanism for raising and lowering the headrest assembly that includes the harness support. The metal rod shown is spring loaded within a slot on the sliding panel of the headrest raising and lowering mechanism, that has the slots for the harness as shown. If the rod is moved against the spring loading away from the seat back it will rise out of the slots on the seat back and therefore allow the panel to move up and down. When the rod is released to return to the bottom of the slot it will engage a notch and thereby lock the headrest assembly in a vertical position represented by that notch.
The metal rod has another function in this embodiment. Because of its strength the harness passes over it and down to the splitter plate that holds the harness in tension with a tensioning webbing as amply disclosed in the background art. FIG. 3-05 shows in addition the position of a section of the harness. As it is attached near the center plane on one or both of the front and back of the seat, it I slightly inclined as shown. However the rod is horizontal. There will therefore be a greater force on the webbing of the harness on the outer edge than on the inner edge, resulting in damage to the harness and possible rupture in the event of a rough rod preventing the harness webbing from sliding inwards upon the high tension forces encountered during front impact. If the sliding friction between the webbing of the harness and the rod is lower the harness webbing slides inwards and bunches up on the inner edge, or even gets forced into the inner side edge of the slot. Such bunching up and getting forced into the inner edge of the slot reduces its ability to slide over the rod during such an impact. The elastic nature of the webbing of the harness is a factor in the design of the shock absorption of the harness during front impact and this is adversely affected as a result as the section of the harness behind the slot and the tensioning webbing attached thereto cannot stretch to accommodate the movement of the child upon such from impact as such stretching would require the webbing to move over the bar and through the slot on the slot which leads the harness to the front of the seat from the back. This problem is accentuated if there are load limiting devices installed on the harness webbing on the rear of the seat or replace the splitter plate or are attached on any section of the harness tensioning webbing. Such splitter plates and harness tensioning webbing are well disclosed in the background art.
This invention provides a solution for this problem FIG. 3-06 with a pair of sleeves (Forms) that are tapered as shown in the FIG. This can be attached rigidly to the lateral rod so that the webbing can slide over it or be slidably attached to rotate about the rod and act as a pulley for the webbing. The latter embodiment will require an end stop on the inner side to prevent the sleeve from moving inwards upon tensile force on the harness that will have a component towards the center along the rod. The profile of the sleeve can be such that it optimally prevent the bunching of the webbing towards the center and prevents it from moving to the edge of the slot. This will therefore aid in allowing the webbing the move freely over the rod and the slot thereby enabling the use of the rear section of the webbing of the harness, the tensioning section and any installed load limiting devices mounted at the back of the seat.
FIG. 3-07 in addition shows an inset with the angled webbing the orientation of the sleeve.
The Sleeve would normally be made of a low friction material such as PTFE or smooth polypropylene (for cost reasons). Smooth Glass filled plastics such as nylon or polypropylene could be effective as the glass on the surface could help lower the friction both against the rod and the webbing. Metal sleeves can of course be used or lowering the friction if weight is not critical.
One of the main challenges in designing load limiters for a seatbelt restraint system is that it needs to accommodate different passenger sizes and therefore masses of the passengers. Larger passengers with higher masses will require higher forces to decelerate them whereas smaller passengers with smaller masses will need smaller forces. The compounding problem is that while a smaller force for a large passenger of high mass will provide good performance in terms of head and other peak acceleration parameters the excursion of the head and other body elements may be excessive. This balance is therefore a critical one in designing a belt system.
The solution of this invention uses the information inherent in a retractor to infer the size of the passenger and then use the architecture of the load-limiter/retractor to provide the appropriate force for decelerating the occupant.
There is also a second class of embodiments that use multiple load limiters that engage at different levels of excursion of the webbing during impact. For example a first load limiter will resist the excursion for a pre-determined excursion threshold (that is adequate for a small mass passenger) and then a second load limiter will additionally engage when the first excursion threshold is passed. Thereafter there may be additional load limiters that may engage at higher thresholds for even heavier passengers.
Another factor that enters into a load-limiter/retractor combination is that the webbing that is wound on the retractor spool can slip or tighten and therefore reduce the effectiveness of the load limiter. There are therefore benefits in reducing the slip of the webbing on a seatbelt in the sections that are wound on the spool of the retractor.
Yet another factor that can be helpful for load limiting using the architecture of a retractor is the elastic properties of the wound webbing or other materials on the spool. Compression of these materials can be useful to get suitable load limiting characteristics.
The adaptive load-limiter/retractor of this invention has several technologies that can each provide a solution for the one or more of the above challenges. They can be used in combination to further enhance the performance of the load limiter.
The figures show embodiments of the invention. The figures do not show the automatic locking mechanism of the retractor but only the spring for the retractor. This is well disclosed in the background art. Any of the architectures of such locking arrangements such the pendulum or centrifugal triggers can be used with the present invention.
The first technology used to capture the information of the size of the passenger and therefore infer and provide the appropriate force in the load limiter, is the length of the webbing that is dispensed by the spool. The spool has a fixed diameter and therefore the number of turns of webbing on the spool will provide the information on the length dispensed. Large occupants will need more webbing dispensed and therefore there will be less webbing left on the spool after dispensing enough webbing to buckle up the occupant. Therefore the effective diameter or radius of the wound up webbing on the spool will be smaller than for a small passenger that will need less length of webbing to buckle up (less dispensed webbing). This invention uses a load limiter along the axis of the adaptive load-limiter/retractor. Notably as the force on the webbing holding the occupant is place is derived from the force on the webbing that touches the wound webbing on the spool or the webbing that is tangential to the roll of webbing on the spool, the force multiplied by the radius of the spool and the spooled up webbing will be the moment of the force that counters the moment created by the twisting of the load limited at the center of the adaptive load-limiter/retractor. As the diameter of the spooled up webbing on the spool rises—with the smaller occupants requiring shorter webbing lengths to be “buckled up”—a smaller force is required to create the same moment to twist the load limiter as the distance or radius of the spool with spooled up webbing has risen. Therefore a smaller force is applied to control a smaller occupant and the larger force is used to control a larger occupant during impact. This architecture of this invention will work well of the ratio of the spool diameter to the thickness of the webbing is in a range that will imply that that spooling up the webbing changes the diameter of the spool with the webbing enough to change the force by what is required. While this is one embodiment of the present invention it may require thick webbing which is both more expensive and less pliable. Several alternative versions of the invention overcome this challenge. A fill tape may be attached to the webbing or simply overlaid on the webbing to “build up” the thickness of each turn of the webbing and therefore quickly build up radius on the spool as the webbing is retracted for smaller occupants and therefore provide a smaller force from the load limiter. The fill tape can be attached at the end to the webbing or at intervals to ensure that it stays with the webbing and gets spooled in with the webbing. Fill tape can be used for other purposes as well such as providing a surface on the webbing that prevents slippage of the webbing on other layers of itself on the spooled section, and also for providing a in the spooled up section a compression characteristic that helps with the load limiting function of the adaptive load-limiter/retractor.
Moreover the further control of the variation of the radius of the wound webbing with adjoining fill tape can be achieved by changing the thickness of the fill tape along its length. Such variation of thickness will change the rate of change radius with the spooled in length and therefore provides a wide variation in forces available for different sized occupants where as a fixed thickness fill tape will have a constant change in radius with spooled in length.
A second tool for varying the load limiter force at the time of impact or tension of the webbing is with a multi element load limiter that are installed concentrically along the axis of the adaptive load-limiter/retractor. This approach can be used on its own or with the spool diameter approach noted above. The first load limiter can be the widest tube with one end attached to the spool and the other end attached to the retractor drum or mechanism which is locked during impact (in the absence of a retractor it is simply fixed to the housing and becomes a simple load limiter). Additional tubes (and a rod at the center is an option) are also attached at one end to the spool and at the other end are enabled to have lag in engaging the retractor. This is shown in the embodiments with a slot open over an arc that engages a pin after the pin has traversed the angle of the arc thereby offering support after a pre-determined rotation of the spool. The first tube may engage immediately upon rotation of the spool as shown in the figures.
Additional tubes or rod for the center may be used with slots of varying angles of arc to control the delay for engaging the load limiter upon rotation of the spool. An alternative embodiment will have fixed connections for all the load limiter tubes/rod on the retractor or fixed side and have the angular slots for delayed engagement on the spool side.
This approach will offer an initial force from the first load limiter tube/rod to offer the resistance required for the smallest passenger, and then after the spooling out of a predetermined length of webbing and rotation of the spool to achieve this the second load limiter tube/rod will engage and so on for the additional load limiter tubes/rod.
FIG. 4-01 shows a cross section of an embodiment of the invention. 12 - 001 is the spool that has axial support on the sides on the housing 12 - 010 . The spool is attached to multiple load limiter tubes/rod (in this case one tube and a rod) with pin 12 - 006 . The load limiter tubes/rod are loosely fitted to the spool to allow rotation if needed, and to each other. On the other side the load limiter tubes/rod are each attached separately to the retractor drum or other retractor assembly. In this embodiment load limiter A which is a tube is attached with pin 12 - 2007 to the retractor drum 12 - 005 . Load limiter B which is a rod has a slightly longer length to protrude outside load limiter A and is attached with a pin 12 - 008 which is in a slot 12 - 011 that does not engage the pin until the spool has rotated through a pre-determined angle. This arrangement will enable the second tool as noted above for load limiting. This second tool for load limiting does not require (but can work with) the information of the effective spool radius. It also therefore does not need a retractor (manual or automatic) to spool in the webbing and change the effective radius.
The first tool for load limiting can be with the design of the webbing to be thick enough to provide the variation in spool effective radius or alternatively with fill tape that provides the required thickness. FIG. 4-06 shows three effective radii of the spool as the webbing (and fill tape) unwind from the spool. For a small passenger the effective radius will be R3. As the webbing (and fill tape) are dispensed for larger passengers, the radius will reduce to R2 and then to R1 for the largest occupant, thereby reducing the moment arm of the force and effectively increasing the force to be in equilibrium with the torque provided by the load limiters at the axis of the spool.
The retractor in the embodiment shown in the FIGS. winds up the spring 12 - 009 as the webbing (and fill tape) is dispensed and reels in the webbing to return to its normal state. There are many architectures for retractors and this is just one architecture for the sake of illustration of the invention. The invention will work with any retractor manual or automatic with a lock manual or automatic during the deployed state.
FIG. 4-02 shows different views of an embodiment that is attached to the vehicle, seat or other fixed object.
FIG. 4-03 is an exploded view that shows the parts of the embodiment.
FIG. 4-04 shows the webbing with the fill tape in the coiled state on the spool.
FIG. 4-05 shows another embodiment that can be attached to webbing rather than to the vehicle/seat/fixed object. The operation is the same.
FIG. 4-08 shows a fill tape of varying thickness to change the rate of change of radius with spooled in length of webbing.
A third tool for varying the load limiter force is by changing effective length of the load limiter rod or tubes in the center of the spool.
FIG. 4-07 is an embodiment of this arrangement. The spool 12 - 001 is adapted 12 - 013 , to have a splined section for a splined (or slotted) hollow shaft section 12 - 015 . This splined tubular axle can move axially with regard to the spool but will transfer torque to the spool. It is attached to the load limiter tube 12 - 016 (in this case only one load limiter tube is used and it may also be a rod) with the pin 12 - 007 However distinct in this embodiment the attachment to the load limiter is with a slot 12 - 017 or other connection that will allow movement of the connector to the shaft 12 - 015 to engage longer or shorter lengths of the load limiter. Typically if a slot is used the properties of the load limiter element with the reduced cross section near the slot needs to be considered. Other connection means can be splines.
Therefore with this arrangement the hollow shaft 12 - 015 can slide up and down the load limiter engaging different points along its length thereby changing the torque/twist characteristics of the load limiter. It is now necessary to provide the load limiter information about the size of the occupant. This information can be generated by knowing the turns of the spool (with our without the fill tape). This information is transferred from the spool to the sliding hollow shaft 12 - 015 with the threads on the surface 12 - 018 that engage the housing of the adaptive load-limiter/retractor. As the spool rotates the shaft 12 - 015 moves axially thereby engaging more or less of the length of the load limiter.
The embodiment shown has the threads overlapping the splines. However other embodiments may have them on separate sections of the cylindrical surface of the 12 - 015 .
The adaptive load-limiter/retractor of this invention may be used for seat belts in all types of vehicles including cars and on harness systems in child seats where the retractor load limiter will replace the front adjuster strap. It may be mounted on the vehicle or seat or in alternative embodiments be mounted on a length of webbing.
Notably variations of the adaptive load-limiter/retractor can be to eliminate the automatic spring operated retractor with a manual retractor by manually spooling in the webbing and locking in place. Some child seat harness systems may be better served with such an arrangement.
A special case of the retractor locking mechanism is shown in FIGS. 4-09 and 10 . This locking mechanism has a ratchet 12 - 020 that rotates with the retractor drum 12 - 005 . As it rotates the key 12 - 021 engages successive notches on the ratchet wheel and prevents motion back. The ratchet key is spring loaded in this embodiment against the ratchet. When the retractor needs to be released the key is pulled back with a cable, webbing or other means attached at 12 - 025 . This allows the retractor to release and feed out webbing against the tension of the retractor spring 12 - 009 . The cable, webbing or other means may also be string loaded to bring back the cable to the position that engages the ratchet key with the ratchet.
Additional features are shown in FIGS. 4-09 and 10 . Secondary spring 12 - 022 “clicks” the motion of the ratchet key between two positions and gives tactile feedback on the cable or webbing. In addition the gongs 12 - 024 with different frequencies for the two domes shown can be struck by the gong strike 12 - 023 when the ratchet key is in each of the two positions thereby giving audio feedback to the user on the position of the key.
Child Seat Shoulder Guard and Harness Support Pulley
As shown in FIG. 5-47 the slider for the shoulder guard has many embodiments. Two additional embodiment as in FIGS. 5-48 , and 49 show the center section and the side sections separate and enabled to be mounted together with rivets or fixed means in one of the embodiments in different positions to give greater or less shoulder room for the child and depending on the width of the seat shell in which it is installed. In the other embodiment the “saw tooth” serrations are utilized where it is easier to move the sides towards the center if the attachment of the sides to the center are spring loaded as with a rivet or bolt but with a spring interposed as well disclosed in the background art. However, during a loading of either of the sides from the inside the saw tooth locks and does not permit the relative movement between the center and the sides. The spring loading holds the saw teeth interlocked.
FIG. 5-50 shows the form used for leading the harness over the support rod. However sometimes it is desirable to have this pulley or form field installable. FIG. 5-51 shows a version where it is two parts that can be locked together (2 parts that interlock in this case the two parts are complements of each other)
In some embodiments the mating surfaces are such that they lie substantially along the circumference of a circle about the axis of the rod and therefore when there is a radial load as during an impact the mating surfaces are squeezed together and do not slide apart. Another embodiment has serrations that interlock on these mating circumferential surfaces that interlock when there is a radial load. A further improvement has a saw tooth shaped serration pattern that allows easier sliding in of the two parts but locks when there is an attempt to separate the parts. The Radial force will help this process of locking the mating saw tooth surfaces
Load Limiters that May be Used with the Harness and Tether in CRS.
FIG. 7-01 to FIG. 7-04,4A, 4B show several embodiments for a load limited that may be used on either the harness (as shown) or for the tether (with end attachments modified)
This class of load limiters are designed to have controllable force displacement characteristics by bending strips of material. The width and thickness of the strips at different points along their length of displacement will determine the force at that point of displacement. The principal application in the CRS is to have constant forces over a given displacement which may be achieved with a constant cross section for the strip for that length. However, it may be desired to have multiple “plateau”s of constant force to cater for different loads on the CRS. This can be done with multiple cross sections along the length of the strip. Of course variable cross sections will give variable force profile as desired.
The embodiments shown have several approaches for securing the lower webbing section of the harness system. Some have slots in the housing body and others have a removable pin that secured the harness adjustment webbing at the lower end.
The housing is either a section of tubing or another cross section of channel or bent metal as shown in FIGS. 7-04, 4A, 4B . Many embodiments have an assembly wedge to keep the deformable strip in contact with the roller. This wedge can be of a flexible material and designed to “wedge in” with a small lip at the front that lies over the bottom edge of the sections of the housing. Alternatively it may be mounted to the housing (eg body tube, or channel sections) with pins or slots and engagement protrusions.
The embodiments shown have a recessed lip for strip support that is designed to calibrate the extent of bending of the strip. The position of this lip will determine the angle over which the deformable strip bends about the roller and therefore the force that is required for activating the load limiter.
The embodiment in FIG. 7-04B has a pin that attaches the lower webbing section. This may have a cotter pin to secure it or other means that ensure it does not slide out.
Proactive Side Guard
The pro-active side guard embodiments shown are designed to have a gap to allow free movement of the harness through the slots for the harness on the rear backplane that raises and lowers the head rest. The shoulder guard is therefore designed to be below the slot position and the head rest above the slot position. Considering however that the shoulder guard with its lateral movement (upon engaging the inertial mass of the child in the seat during lateral impact), actuates the headrest about the connection point at 15 - 3003 , 15 - 3004 , the shoulder guard needs to be designed with a protrusion in the center to allow the slot on the shoulder guard to engage the pin on the headrest. Some embodiments in addition as shown may have a recess on the headrest that fits the protrusion on the shoulder guard that can transfer the required force. In some embodiments the pin attaching the headrest to the shoulder guard can have a reduced function of simply indexing the protrusion to the recess in the headrest or in other embodiments completely eliminated.
The headrest is attached to the height adjustment backplane 15 - 3005 with a pair of links 15 - 3002 that in the normal position are angled and when actuated by the shoulder guard, rotate the headrest as shown in the FIGS. 7-05, 6, 7 ( FIG. 7-05 shows the back plane as well). FIG. 7-08 shows the normal position of the headrest and the side guard.
Modular Arrays of Attached Occupant Supports in Vehicles
A major challenge in evaluating the crash performance of occupant support units (units) in vehicles when they are linked together in arrays is that the forces and kinematics of the array will depend on the number and configuration of the individual occupant supports in that array and the forces that act between them. As a result a conventional approach to testing these arrays would need to destructively test the complete array as it is deployed in for example an aircraft. Moreover, the sled facility will need to accommodate this very large array as well.
These two requirements of destructively testing a number of such occupant supports on each test and the use of a large sled for testing can create serious cost barriers for the testing and certification of these arrays resulting in the economic penalty of testing and certification deterring the use of these arrays on their economic merit.
Therefore a cost effective method for testing such arrays will be enabling for the use of such arrays in vehicles such as aircraft. High occupant densities in such arrays can result in great economic value for the deployment of these arrays and therefore such a method for testing will have substantial economic value.
This invention provides a method to evaluate the performance of a large array with a small subset of the units in the array thereby requiring only a few of the occupant support units for destructive testing and also requiring a much smaller sled facility for these tests, thereby enabling the evaluation of the large arrays for a substantially reduced cost. The method therefore has significant economic value in enabling the deployment of such arrays of units.
Certain types of arrays of occupant supports such as the tiered architectures disclosed here are supported along seat tracks in the aircraft. Such arrays have a property that as the array gets longer with identical supports for each of the elements of the array, as the base increases the moment of the force through its center of mass along the axis of deceleration (which may be the axis of the aircraft of the aircraft or an axis that is inclined vertically to the axis of the aircraft to account for vertical loading in a crash situation) is countered by an increasing moment arm as a result of the longer base of the array. On the other hand the moment arm of the inertial loading remains the same along the direction of the seat tracks.
Consider FIGS. 5-01 to 5-05 .
They show the cases of a two tier array of units. The arrays considered are:
1. 2 Lower/1 Upper 2. 3 Lower/2 Upper 3. 4 Lower/3 Upper 4. 5 Lower/4 Upper
M—Mass of each unit acting through its center of mass.
X—width of each unit
f—deceleration of the vehicle
Y 1 —height from the support seat tracks of the mass of the lower tier of units
Y 2 —height from the support seat tracks of the mass of the upper tier of units
X i,j —support base length in the direction of motion of the aircraft or vehicle.
φ(x ij )—force density along base of array attachment to latches dependent on location.
g—acceleration due to gravity.
d—displacement of upper tiers away from lower tier along axis of aircraft/vehicle.
1—Upper tier unit
2—lower tier unit
3—base support unit
4—seat track
Notably in the architectures shown there are tensile and compressive forces along the base of the array that counter the moment of the forces due to the inertial masses decelerating. Moreover there are compressive forces that counter the gravitational force or weight of the units acting on the seat tracks.
It is seen that when assessing moments of forces at the front edge of the base of the array, that the moment due to the weight of the array and any tensile force on the latches holding the array on the seat tracks counter the moment of the inertial loading due to the acceleration “f” (against the direction of motion). When the acceleration “f” is much higher (eg 16 Gs) than the gravitational force on the array there will be a high tensile force holding the array down. (ie from the FIGS. 1-4 the acceleration “f” on the tracks will create a clockwise moment of the inertial load of the array. This will need to be countered by the small gravitational loading and a tensile force towards the far or back end of the array to “hold down” the array)
It can also be seen that as the length of the array increases the distance of the force due to the inertial loading as a result of the “f” will rise proportionate the number of upper and lower units in the array. However the moment arm that is the vertical distance of these forces remains the same. On the other hand as the array gets longer the distance of the latches on the base of the array get on average further away from the front edge. Therefore the moment arm of the latch forces rise and lower forces are needed to counter the inertial load of the acceleration “f”.
In an angled test of the seat tracks at an inclination a to the horizontal, ( FIG. 5-01A ) there is an inertial loading that is horizontal of which there is a component in the direction the seat tracks (Y) (horizontal when α is 0) and a component that is at right angles or orthogonal to the seat tracks (Z). The component of the inertial loading horizontal to the seat tracks has the same effect as in α=0 case.
The orthogonal (Z) component now has the reaction force changing to accommodate the inertial loading of the array. Therefore the reaction forces in the Z direction will differ from the horizontal case in that there is an additional compressive force to counter the inertial loading in the Z direction during the acceleration. (The gravitational force is also now only the Z component of the horizontal case but this is in any case small when accelerations of the order of 14-20 Gs are considered for the inertial loading) Overall this would result in an increase in the compressive loading along the base and a decrease in the tensile loadings along the base. Therefore the maximum tensile loadings will occur in the horizontal case. The angled orientation as noted is equivalent to a horizontal seat track with the loading at an angle as in a crash landing with a significant vertical component. (the only difference is the relatively small gravitational force compared to an deceleration of 14 or more Gs) Notably in both inclined and flat cases as the array increases in length the latch forces drop. Moreover as the latch forces drop the resulting displacement of the array due to the latch forces decrease resulting in lower projections of the head of the occupant as a result of the displacement of the units relative to the seat tracks. This also reduces the head acceleration of the occupants in the units.
In the inclined case the lumbar loadings are largely determined from the Z inertial loading. The levels are determined by both the (clockwise in FIGS. 5-01 to 5-05 ) moment on the array due to the Y component and the Z direction direct loading. While the Z component is constant along the base the Y component torque will force the rear side up and push the front side down (both in reference to the axis of the aircraft). Overall for an angle of α=60 degrees for example the z-component is (i+j)Mf Cos α or (i+j)Mf·0.707
Which is a significant part of the loading and will be equally distributed along the base. The y-component will be (i+j)Mf Sin α or (i+j)Mf·0.5. This component at this angle and will cause the clockwise moment to pull up the rear side and push down the front side of the array. As the array size increases the latch forces supporting the moment due to the y-forces will fall.
Both the y- and z-components are affected by the small increase in the mass per latch as the array size Overall the variation in the force as a result of the y-component as the array size increases dominates and while the peak forces are nearly unchanged with increasing array size the forces fall with increasing array size.
This is another aspect of the invention for lumbar loadings.
Intuition for the method of this invention can be gained from the following analysis:
It is seen that particularly for f>>g (as in crash conditions eg 16G for f) there is a monotonic decrease in the force density of the tensile and compressive loadings across the base due to the inertial loading that dominates the compressive force due to the gravitation loading.
Equating moments about the near edge of the array,
∫
0
X
·
i
φ
z
(
x
ij
)
·
x
ij
dx
=
(
i
·
My
1
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My
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f
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(
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k
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+
∑
k
=
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i
-
2
(
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In the interest of simplicity considering that there is a gravitational force that is countered by the reaction force that is M(i+j)g distributed uniformly along the bottom and assuming a linearly varying force to counter the inertial loading of “f”.
φ z ( x ij )=φ zA +φ zB ·x ij
Where φ zA , φ zB are constants. Notably φ zB would allow a tensile force along a part of the base to counter the inertial load of “f”.
Therefore,
∫
0
X
·
i
(
φ
zA
+
φ
z
B
·
x
ij
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x
ij
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(
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For I>2 there is the general simplification
(
φ
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2
2
+
φ
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3
3
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·
i
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=
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-
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(
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-
3
)
·
d
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With no inertial loading,
There is only the gravitational force and M·(i+j)g=φ zA ·i·X
Therefore=φ zA can be determined.
The remaining constant φ zB must cause a tensile loading increasing with distance from the near edge (front edge). This tensile loading constant falls with increasing values of i,j because the force is deployed over a longer base. This is particularly so when y1, y2 are small compared to i·X. The resulting force from the sum of the tensile force and the compressive constant force must be tensile at the far end and compressive at the near end. Finally the equations take into account the load of the upper tier on the lower tier and the support latches directly below them. It is seen from FIG. 5-44 that as the array gets longer the loading becomes asymptotic at 2.0. This loading change does not affect the horizontal case or the Y component. Moreover, in the angled case while it affects both the y- and z-components, this effect is dominated by the variation in latch loadings to the inertial loadings resulting from the Y components. (The z-component is constant except for the rise in mass which affects both y and z-components)
Simulations support the method of the invention empirically. These simulations are based on a more realistic case where each of the base units have 4 latches—2 on each of the tracks and towards the front and back edges of the base units.
The human mass is that of 95 th percentile male or about 220 pounds/6′2 . This is about 30% higher than the loadings in standard tests for certification of 50% percentile males. The actual values of forces and loadings are therefore higher than what would be experienced in standard tests.
For the “flat” case the acceleration pulse used was triangular with a peak of 17 Gs a rise time of 90 mS and a fall time of 90 mS. The 60 degree inclined case had an input acceleration peak of 16 Gs rise time of 90 and a fall time of 90 mS. The latches are designed to have a vertical and horizontal shock absorption feature.
Notably the arrays are made of deformable materials and therefore the latch loadings accommodate the deformations. The simulations also show the rebound and the related forces over time.
FIGS. 5-36 to 50-43 Show the cases of a two tier array of units. The arrays considered are:
1. 2 Lower/1 Upper ( FIG. 36, 37 ) 2. 3 Lower/2 Upper ( FIG. 38, 39 ) 3. 4 Lower/3 Upper ( FIG. 40, 41 ) 4. 5 Lower/4 Upper ( FIG. 42, 43 )
The plots in FIGS. 5-08 to 5-28 show the forces for each of the arrays 1-4 at the latches. Notably these graphs include the initial force and the force during the rebound.
FIGS. 5-08 and 09A , B, C, D shows the overlay of the Cases in 1-4. It is readily seen that the maximum forces are monotonic decreasing with the number of units in the array. This supports the arguments above and the method of this invention.
FIGS. 5-10, 5-12,5-14, 5-16 show respectively the forces along the track for the 4 cases considered. (These are the contributing forces to the FIG. 5-08 )
FIGS. 5-11, 5-13, 5-15, 5-17 show respectively the forces orthogonal to the track (vertical in the flat case). It will be seen that there are compressive and tensile loadings from the opposite ends of the array as predicted in the analysis the tensile forces are on the latches nearer the rear of the array regardless of how long the array is. The force variation for the initial impact and the rebound are also seen. The forces are seen to be arranges in pairs. Each pair represents a rear and a front latch (with regard to the occupant axis) the pairs being arranged from the front of the aircraft to the rear of the aircraft along the base units as noted above.
Moreover to assess the increased compressive loading in the angled case, FIGS. 5-19 and 5-20A , B, C, D are presented. It is seen that the compressive loads are monotonic decreasing with the array size.
FIGS. 5-21, 5-23,5-25, 5-27 show respectively the forces along the track for the 4 cases considered. (These are the contributing forces to the FIG. 5-19 .)
FIGS. 5-22, 5-24, 5-26, 5-28 show respectively the forces orthogonal to the track (vertical in the flat case). It will be seen that there are compressive and tensile loadings from the opposite ends of the array as predicted in the analysis the tensile forces are on the latches nearer the rear of the array regardless of how long the array is. The force variation for the initial impact and the rebound are also seen. The forces are seen to be arranges in pairs. Each pair represents a rear and a front latch (with regard to the occupant axis) the pairs being arranged from the front of the aircraft to the rear of the aircraft along the base units as noted above.
Moreover as a result of the smaller displacements the resulting maximum head accelerations are seen to be monotonic decreasing with the length of the array. FIGS. 5-18A , B, and C show the dominance of each of the tested positions (in the 2×1 configuration) with regard to the simulated head accelerations in the other longer arrays. Moreover FIG. 5-34 table shows the HIC values that demonstrate this dominance. This supports the method of this invention for testing head accelerations and HIC.
Finally lumbar loads (in the inclined tests) as seen in FIG. 5-29 to 5-35 support the monotonic decreasing lumbar loads with increase in array size and therefore support the method of this invention. In addition to the component of the lumbar loading that is a direct result of the component of the acceleration “f” “pushing up” the occupant in the Z direction, there is the effect or rotation pulling up the rear side and pushing down the front side (with regard to the aircraft axis) as a result of the Y component which will increase the lumbar loadings on the rear side relative to the front side. This is seen in FIG. 5-29 where the Upper passenger 1 Lumbar loading in the test configuration dominates the lumbar loadings of any and all the other Upper passengers in the longer arrays. Similarly FIG. 5-30 shows the same for the Lower Passenger 1 and FIG. 5-31 shows the same for lower passenger 2. FIG. 5-35 shows the table of lumber loadings that supports the method of this invention.
Variations of the cases considered where the axis of the passenger is not directly lateral with regard to the aircraft axis but inclined to the lateral are not significantly different as the same principles apply.
The inference from this analysis and simulations is that it is possible to test an array as in 2 Lower/1 Upper and infer the performance of longer arrays that will perform better with regard to lower track loadings and lower head accelerations and lumbar loads.
The method claimed is for a testing methodology for a contiguous array of occupant supports supported by each other and by a seat track below, and wherein the array has a second tier of occupant supports attached thereto, comprising-testing for axial accelerations and accelerations with an axial and vertical component of a subset of the array with a minimal number of units (eg 2 lower units and 1 upper unit) to meet a requirement or regulation for forces displacements, head accelerations and lumbar loads and using the dominance or monotonicity arguments presented here, infer the better performance of the longer array, thereby avoiding the crash testing of the longer array at greater cost.
Latch for Attachment of Modular Occupant Supports:
FIGS. 5-06 , FIG. 5-07 show different views of an embodiment of the latch mechanism.
During crash loading conditions the units of this embodiment will undergo severe spikes in acceleration. The latch mechanisms of this invention provide the shock absorption needed for the units both to protect the units and the occupants and to reduce the peak loading o the seat tracks.
The latch arrangement has a set of sliders that are inserted through the apertures on the seat track and can slide to positions between the apertures under a flange. This allows these sliders to accommodate tensile loadings from the attached units or occupant support bases. The horizontal movement is locked with one or more pins 13 - 012 . On the body of the latch 13 - 011 there is a slide cavity that has a horizontal slider inserted therein. There is in addition in some embodiments a slider support 13 - 013 . A horizontal slider 13 - 015 is enabled to slide within the cavity and is controlled with a spring damper 13 - 015 . An additional spring damper may be inserted on the other side of the slider as well. This will be useful if the system is under damped and a movement passed the normal position is anticipated after an impact load is introduced. For vertical shock absorption there is the optional slider 13 - 016 that is controlled for upward and downward motion by spring dampers 13 - 018 and 13 - 019 respectively.
The Unit/base/occupant support is attached to the pin aperture 13 - 019 . The latch may be attached to a single module or to two adjoining modules thereby contributing to neutralizing the tensile and compressive forces resulting from the inertial loads of the two modules in a rapid deceleration of the vehicle.
Some embodiments of the AirSleeper design with a tiered architecture are disclosed. This invention increases the packing density of the aircraft cabin while maintaining the creature comforts with space of the occupants and thereby provides greater value per unit volume of the cabin. The mini-cabins shown the drawings may be laterally placed or placed at any angle to the lateral direction of the aircraft or vehicle. Angles close to the lateral position are an advantage for safety.
As shown in FIG. 6-01 to 6-05 the array of Air Sleepers as shown here comprise a set of base units which would typically be used for storage and either contain the support structure for attachment to the seat tracks integrated within them or attached to them. These are referred to as the bins. As show in FIG. 6-05 the base unit bins may have drawers that pull out for storage. Moreover these storage drawers may have one or more loops of belt from the rear to the front to transfer the stored items from the rear of the bins to the front for access. These belts have pulleys at the rear and the front and the belt may be supported along its length in between by a low friction surface or multiple rollers. Details of the bin and the parts therein are shown in FIG. 6-15 . Belts may be manually operated by pulling or pushing baggage or motorized as well disclosed in the background art for motorized pulleys and wheels.
If a lower profile for the AirSleeper array is preferred another embodiment will not use the Bottom bins at all and attach the AirSleeper mini-cabins directly to the floor of the aircraft or on the seat tracks.
The storage in these cases may be above the upper sleepers which will then have a structure similar to the lower sleeper mini-cabins to support components above them. The draws may not be useful but doors at the front of the bins will access stored baggage that can still ride on the belts.
Attached to the lower bins are the AirSleeper lower mini-cabins. The lower mini-cabins have a structural purpose as well for supporting the upper mini-cabins and therefore require additional bracing structure. The Figures show that the seat movement machinery lies in the space directly under or behind the seat bottom but the space under arm rests 14 - 025 , are used for bracing ribs and the lower end of the shear plane 14 - 013 that braces the lower cabins. Between the ribs there are optional pop-up storage spaces. They may also be storage spaces that have hinged or sliding covers. The top surface of these will be a part of the arm rest in the sitting position of the occupant and part of the bed surface in the sleeping position of the occupant and therefore will be suitably covered for comfort.
The seat back supports 14 - 001 have side wings to support the occupant in the event of rapid deceleration of the vehicle. The back support also has in most embodiments the air supply for ventilation, reading lights, headphone sockets and one or more projectors installed on the edge of the side walls to project approximately along the line of sight of the occupant lying face up, regardless of course of the position of the seat back. The projection surface may be the mini-cabin ceiling, a table top inclined to be vertical for the purpose, or the ceiling of the aircraft cabin for the upper mini-cabins. The air supply vents may be directed from the upper edges of the sides of the seat to provide a constant clean air supply for the occupant. As shown in the FIGS. 14-010 , the steps are placed on the edge of the lower Air Sleeper mini-cabins and the upper mini-cabins displaced laterally to accommodate this. This allows excellent egress ingress for the lower occupant. The feet and legs of the upper occupant are separated from the space of the lower occupant with a screen 14 - 011 and the upper section of the rear wall 14 - 013 . The rear wall 14 - 013 is also a shear “Plane” (may not be flat) that support the mini cabin structure in the event of rapid deceleration of the aircraft/vehicle. Notably the shear plane needs to be narrow at the lower end so that the space of the lower passenger is not compromised. The plane is typically at the knee position of the lower passenger and a slightly narrower space at that point can be accommodated by the passenger.
The upper mini-cabins have a limited structural role and do not need to support above them in most embodiments. They have a support structure for the monitor/camera/projector and also for conducting oxygen to the oxygen mask container towards the end at the top of this support 14 - 008 . The Camera may be used for video conferencing, the projector may project on the table (not shown but deployable from the side wall of the mini cabin). If oxygen generator is used this may be housed in the support mount 14 - 008 . 14 - 007 shows a monitor or projector although the projector may be housed directly on the mount 14 - 008 .
As shown in FIG. 6-05 the bin drawer 14 - 015 may be pulled out onto the aisle for storing or retrieving baggage.
FIG. 6 shows the perspective of the lower mini-cabin occupant. On the left is the stairs for access to the upper mini-cabin. A screen or projection space may be on the rear of the wall behind the stairs. The top recess adds space to the lower mini-cabin and lies under the arm rests of the upper mini-cabins.
FIG. 6-07 shows another aspect of the space efficiency achieved in this invention. The steps at the lower end will interact with the space of the lower occupant and therefore needs to be designed carefully. In some embodiments of the invention, the a section of the mini-cabin 14 - 023 is cut out for foot space on the first step which may lie below it. The cutout may also extend to the side section of the leg rest (not-shown) Moreover the second step 14 - 022 is contoured to be towards the end of the mini cabin so that the leg space of tall occupants in the lower mini-cabin is not compromised.
FIG. 6-11 shows the handles for easy egress and ingress to the upper mini-cabins. Additional handles may be installed along the edge of the lower mini-cabins as well.
FIG. 6-12, 6-13 show the mechanism for changing the seat position from lie flat to sit upright. There are many possible actuator mechanisms both linear and rotational. One is shows with an attachment point at the rear of the seat pan. The seatback anchor is supported by a pivot 14 - 031 to move from the flat bed position to the seated position. In addition at the lower end of the seat back there is a pivotal attachment to the seat bottom 14 - 032 . As may be seen from the figures, the seat bottom moves forward when the seat tilts back to the flat bed position. The seat bottom in this embodiment at its front end has sliders or rollers 14 - 030 in a slot 14 - 029 that directs the vertical position of the seat front as it moves back or forwards thereby defining the angle of orientation of the seat bottom.
In another variation of this architecture, the pivot 14 - 031 is not at a distance from the bottom edge of the seat back along the seat back as shown but rather is on one or more arms that are attached to the bottom edge of the seat back protruding backwards (in the sitting position) or under (in the flat bed position) the seat back like an elbow that could be substantially at right angles to the seat back. The pivot to the support pan on the mini-cabin is at the end of this arm. The pivot 14 - 032 is at the end of the seat back as in the illustrated embodiment. This arrangement will pull the seat bottom back (rather than forward) as it goes to the flat bed position and the slot heights will be reversed so that the front of the seat bottom rises as it moves back.
The advantage of this arrangement is that the length of the noted arm can be varied (and the slot as well) to change the height of the seat back and bottom in the flat bed position to benefit the lower occupant, and bring the seat bottom forward in the sitting position for the upper occupant This architecture is shown in FIGS. 6-16 and 6-17 . The figs show only the ends of the slots where the pins are. The contour can take any shape for preferred orientations during recline.
FIG. 6-14 shows the center section of the leg rest that may be retracted under the seat bottom in a slot under it. An alternative design will have the center section of the leg rest hinge down at the front edge of the seat bottom. There are many actuator mechanism for retraction of leg rests in the back ground art. This invention however proposes some embodiments to have the same actuator used forth e seat back angle support to also actuate the center leg rest by utilizing limit switches that lock the seat bottom at the end of the movement desired and lock the end of the actuator to the center section of the leg rest to push it out or pull it back. Notably this attachment may need to have levers or gears well disclosed in the background art, to increase the movement with reduced force required. When the center leg rest is full retracted and detected by limit switches, the actuator end is unlocked from this mechanism and locked onto the seat back engagement point to move the seat back.
The Seat Bottom Mechanism
Mass and weight are not desirable in aircraft architectures and therefore a fewer number of actuators required for a seat mechanism has utility.
This mechanism is designed to actuate the angle of the seat bottom (and seat back); the movement of a sliding leg rest and the movement of wings and/or extensions to the leg rest if needed. Notably the force/displacement ratios can change drastically between moving a seat with a high mass occupant on it vs moving a leg rest or other small parts. The former may need a high force and a small displacement particularly if near the axis of motion to provide the required torque at that axis, and the leg rest may need to move a large distance but with a small force. These requirements are accommodated in the design.
Actuation of the seat back and bottom angle is achieved by attaching the seat back on the pivotal support 16 - 1014 and attaching the seat bottom on the seat back with pivotal support 16 - 1015 . The front of the seat bottom can slide in this embodiment along a path that is predefined to provide the desired seat bottom angle at different recline angles of the seat back. This and any other seat back and seat bottom architectures that require the motion of a point on the seat bottom can utilize the present invention.
This invention uses locks or spring loading to channel the available force/movement of the actuator to the desired point. In one embodiment the seat bottom (or back) has locking points at different orientations available from the motion of the seat bottom. Initially the Main Slider is locked to the seat bottom 16 - 1009 . This ensures that when the seat bottom is not locked on its one or more locking points the seat bottom moves as the 16 - 1009 is locked. At the desired position of the seat bottom the seat bottom lock is actuated and concurrently the lock 16 - 1009 is released. Thereby locking the seat bottom (and the seat back) in the desired position and transferring the motion to the main slider. The motion can of course be stopped at any time by stopping the actuator.
In a first embodiment, with a single lever, as the actuator motion continues the main slider 16 - 1004 is actuated and actuates the Pusher rod 2: 16 - 1006 by moving its pivotal attachment thereto. The Pusher rod 2: 16 - 1006 is designed to work as a lever, providing motion amplification (with force de amplification) for the leg rest assembly which slides on the seat bottom. One end of the pusher rod 2 has a slot that slides over a pin on the seat bottom. The orientation of the slot and its shape is designed to have a surface of contact that is as close as possible to the radial direction with regard to the pivotal connection to the Main slider 16 - 1003 . The moment arm is short between this point of contact and the pivot point whereas the moment arm is longer with regard to the contact point of a similar slot that engages a pin on the Slider 16 - 1002 on the sliding leg rest 16 - 1001 . This slot is designed to have an orientation and shape to make the contact surface between this pin and this slot as close to the direction of motion of the slider 16 - 1002 .
However with multiple levers connected end to end or serially we have a multiplication of the motion with a proportional reduction in available force. In a second embodiment, a multiple “scissor” or “accordion” movement is possible with multiple pairs of levers attached pivotally in their middle to each other, the ends of a first pair of levers pivotally connected to the seat bottom but also enabled to slide orthogonally to the slider direction so that when the “scissor” closes the ends can come together. The pivot of the first lever pair is pivotally attached to the slider, and therefore as the slider slides away from the first ends of the first pair of levers the scissor will close. The second ends of the first pair of the levers are attached to the first ends of the second pair of levers pivotally and as the first ends of the first pair of levers move together it forces the second end of the first pair to move together and as the first end of the second pair of levers are pivotally connected these move together also. Multiple pairs of levers connected in this fashion with the second ends of one pair connected to the first end of another pair will give a series of serially connected levers. As the slider moves and moves the pivot of the first pair of levers the entire assembly will extend. Therefore the leg rest connected pivotally to the second ends of the last pair of levers with these connections enabled to slide together orthogonal to the slider direction will push the leg rest forwards. The converse will happen as the main slider moves back.
The original movement is passed to the first ends of the first lever pair and the second ends drive the first ends of the second lever pair and so on for multiples of such lever pairs interconnected resulting in a multiplication of the movement of the first scissor whose input is the force/displacement designed for the movement of the seat bottom to move the move the leg rest which needs a much larger motion and smaller force. The number of lever pairs and the length of the levers will be factors that determine the amplicifation.
At or before the time of motion of the main slider 16 - 1003 , the lock 16 - 1008 between the leg rest and the leg rest slider needs to be engaged thereby ensuring that the movement of the leg rest slider is directly transferred to the motion of the sliding leg rest base 16 - 1001 . Following a predetermined distance of motion of the leg rest base 16 - 1001 , the leg rest may be locked (lock not shown) to the seat bottom and concurrently the lock 16 - 1008 between the leg rest base and the leg rest slider is released so that the motion is transferred to the leg rest slider but not the leg rest base. This motion of the slider will directly move the front flange of the leg rest slider and/or move the side slider 16 - 1004 on either side of the leg rest (one side shown) for additional support of the legs.
The side slider is activated by the pivotal attachment with pusher rod 1: 16 - 1005 which is pivotally attached to the leg rest slider and to the side slider and has an orientation that allows the translation of the motion to the lateral direction.
The reverse process will occur as the actuator direction is reversed and the lock mechanism activation is reversed. Notably spring loadings of each slider mechanism may be used to change the force characteristics as the displacement proceeds.
A second embodiment that does not use switching locks may work as follows. End stops are arranged for the seat bottom motion with regard to the support structure of the AirSleeper, and the leg rest base with regard to the seat bottom. Strong spring loadings are used first between the seat bottom and the main slider 16 - 1003 to prevent the main slider from moving relative to the seat bottom 16 - 1000 before the end stop of the seat bottom is reached. Thereafter the force on the end stop will prevent further motion of the seat bottom and the spring between the seat bottom 16 - 1000 and the main slider 16 - 1003 will compress an allow the main slider to move thereby actuating the pusher rod 2: 16 - 1006 which will move the leg rest slider 16 - 1002 . However a strong spring between the Leg rest slider 16 - 1002 and the leg rest base 16 - 16 - 1001 will prevent the leg rest slider from moving relative to the leg rest base and therefore the leg rest base will move relative to the seat bottom till its end stop is reached. Thereafter the end stop will prevent further motion of the leg rest base and thereafter the leg rest slider will move against the spring loading to actuate the flange 16 - 1007 and/or the side sliders 16 / 1004 . The motion as the actuator shaft retreats will follow the same sequence in reverse.
There are many arrangements possible for all the pivots and slider arrangements disclosed in the background art that may be used in this invention.
AirSleeper Stair Arrangement
As shown in FIG. 8-05 to 8-08 the stair profile is recessed into the AirSleeper enclosure. The advantage is that there is more aisle space at hip to head level. In addition this invention provides a grade on the stairs that is ergonomically attractive for egress and ingress. Finally the stairs are arranged not to interfere with the lower passenger movement as they are at the extreme end of the lower passenger space and on one side. The motion of the seat bottom and its extensions do not interfere with the steps in this embodiment. The upper AirSleeper module will have a shorter front end as a result and therefore for the sleep or flat bed position it will be desirable in some embodiments to have an extension of the leg rest forward and in the case of narrower leg rests to the side as well. This is disclosed in this invention as well above. | The invention relates to device for providing a safety for passengers and to devices, providing the passenger comfort. There are disclosed variants of load limiter accomplishment for a restraint a passenger in a vehicle, which have a possibility to hold the preliminarily given force. The invention concerns a multi-passenger modular array oftiered passenger supports, having a several levels, means for attaching the modules, locking devices, attaching the modules to the vehicle floor, a drive mechanism for seats in the module, a mechanism for protecting the head of passenger, which is positioned on the seat. The means for providing the passenger comfort head are characterized by the position of steps in the modules, providing a sufficient space for free positioning the legs of the passenger in the upper and lower modules and in the zone of passage between rows. There are also disclosed the presence and position of the bins for storing packages, a construction of armrest and means for lighting, air conditioning, for information drop on the screen and for supplying an oxygen, in necessary. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present Utility patent application claims priority benefit of the U.S. provisional application for patent Ser. No. 60/851,712, entitled “A Device for Containment and Protection of a Liquid Handling System” and filed on Oct. 14, 2006 under 35 U.S.C. 119(e).
FIELD OF THE INVENTION
The present invention relates generally to water systems. More particularly, the invention relates to a device for the containment and protection of a liquid handling system enabling easy installation and removal.
BACKGROUND OF THE INVENTION
Several issues have been identified with liquid handling systems. One of these problems is that fluid pumping devices installed in homes or other buildings leave room for extensive damage by defective or worn out devices. Defects such as, but not limited to, failed and leaking pressure tanks and bad pressure switches may cause pressure relief valves to release water into the building and can cause water damage and mold issues inside the building. Another issue is that valuable building space is occupied by liquid handling systems. Other problems include, without limitation, limited access to the device due to physical building limitations, and hazards caused by the proximity of electrical devices. These issues may be avoided by housing the liquid handling system in a containment device outside of the building.
The current art provides some methods for housing liquid handling systems. For example, without limitation, separate “pump houses” may be built to house liquid handling systems. However, pump houses are expensive to construct and may not be appealing in a yard. In cold climates, pump houses must be heated to prevent freezing. In warm climates, pump houses tend to cause the liquid to warm up, and if this is a drinking water system, it may not to pleasing or refreshing to drink warm water. Also, pump houses tend to be confining and tend to collect everything else around the house or facility including, without limitation, toxic items such as, but not limited to, herbicides, and pesticides that should not be stored near water systems. This collection of objects also creates problems and safety issues with servicing the equipment of the liquid handling system. Pump houses are often dirty and filled with insects. Pump houses can become homes for pests such as, but not limited to, rodents, poisonous spiders, snakes, etc., creating additional health hazards. Also, pump houses require maintenance themselves including, without limitation, regular painting, cleaning, and roof maintenance.
Another solution is to house liquid handling systems in concrete “well rings” buried in ground. Concrete rings allow for the placement of a liquid handling system in-ground and protect the liquid handling system from freezing and resist vandalism, although less expensive than pump houses. However, concrete rings are still costly. Concrete rings are very heavy and may require a boom truck or truck-trailer to deliver and may require a crane, backhoe or similar device to set in-ground. Use of concrete rings requires entering a confined space to work on the water system device. Confined space issues include, without limitation, hazardous gasses, and electrical safety issues that actually may not meet electrical codes. Also, these concrete rings are not very tight, allowing nuisances such as, but not limited to, bugs, snakes, water, etc. to enter the concrete ring. It is also difficult to get plumbing through the concrete ring. The lids of these concrete rings are often very heavy and may require hoisting equipment to remove. The use of concrete rings does eliminate or minimize potential water damage in structures from leaking devices, and provide some protection from weather. Use of concrete rings in ground may be more aesthetically pleasing than a building, but is still somewhat of an eyesore. Furthermore, with the advent of new variable speed pumping systems and computerized pumping systems, it is necessary to have devices as big as concrete rings to house these smaller components.
In view of the foregoing, there is a need for an improved containment device for a liquid handling system that protects the liquid handling system from the elements and pests, is simpler to install than current containment devices, and provides easy access to the liquid handling system.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
FIGS. 1 , 2 , and 3 illustrate an exemplary vault assembly for a liquid handling system containment device, in accordance with an embodiment of the present invention. FIG. 1 shows a front view; FIG. 2 shows a side perspective view, and FIG. 3 shows an exploded view;
FIG. 4 illustrates a side perspective view of an exemplary quick connect adapter from a liquid handling system containment device, in accordance with an embodiment of the present invention;
FIG. 5 illustrates a side perspective view of an exemplary quick connector assembly from a liquid handling system containment device, in accordance with an embodiment of the present invention; and
FIG. 6 illustrates a side perspective view and an exploded view of an exemplary optional quick connect assembly for a regulating device, in accordance with an embodiment of the present invention.
FIG. 7 illustrates a side view of vault 8 with cutaway showing Quick connect 6 and 11 mounted on sidwall of vault.
Unless otherwise indicated illustrations in the figures are not necessarily drawn to scale.
SUMMARY OF THE INVENTION
To achieve the forgoing and other objects and in accordance with the purpose of the invention, a device for containment and protection of a liquid handling system is presented.
In one embodiment, a containment device for a liquid handling system is presented. The devise comprises a vault comprising a cavity of sufficient dimensions to contain at least the liquid handling system, a closed bottom and an open top. A supporting device comprising a first half of a quick connect system connected to external plumbing is positioned in a lower portion of the cavity and secured to the vault in a manner to provide support for a weight of the liquid handling system. A bracket comprising a second half of a quick connect system connected to internal plumbing for the liquid handling system is configured to retain the liquid handling system, contact the supporting device when the bracket and liquid handling system is lowered into the cavity and mate the first second halves of the quick connect system allowing liquid to flow from the external plumbing to the internal plumbing. A lid is secured to the top for minimizing the intrusion of environmental elements into the vault. In another embodiment, the device further comprises an alignment feature for guiding the bracket to properly contact the base. In another embodiment, the device further comprises an additional quick connect system for plumbing of regulation devices for the liquid handling system such that the regulation devices can be removed from the vault without removing the liquid handling system. In an embodiment, the regulation device is a gauge. In a further embodiment, the device further comprises a means for lowering and lifting the bracket and liquid handling system in the cavity. In an embodiment, the means for lowering and lifting is a lifting pipe attached to the bracket. In another embodiment, the external plumbing is attached to mainlines outside the vault. In a further embodiment, the vault is fabricated in a manner suitable for being buried below ground. The device is further fabricated to minimize distortions from soil pressure. In another embodiment, the device further comprises fasteners for securing the lid to the top. In yet another embodiment, the bracket retains the liquid handling system by fastener means. In another embodiment, the vault is constructed of a plastic material or galvanized steel. In another embodiment, the lid is constructed of molded plastic or fabricated metal.
In another embodiment, a containment device for a liquid handling system is presented. The device comprises a means for housing the liquid handling system, a means for quick connecting and disconnecting the liquid handling system from external plumbing, and a means for protecting contents of the housing. In a further embodiment, the device further comprises a means for lowering and lifting the liquid handling system in the housing. In yet another embodiment, the device further comprises a means for guiding the lowering of the liquid handling system. In still another embodiment, the device further comprises a means for minimizing distortions to the housing when the device is buried under ground.
In another embodiment, a quick connect device for use with a containment device for a liquid handling system is presented. The device comprises a connector shoe comprising a flat area with a plurality of openings for accepting a plurality of plumbing connectors on a first side of the connector shoe, the connector shoe retaining a plurality of O-ring type sealers in groves on a second side and placed circumferentially about the openings, and a connector base comprising a flat area with a plurality of openings for accepting a plurality of plumbing connectors on a first side, a slotted perpendicular boss along two edges of a second side, the boss dimensioned and positioned to hold in place the connector shoe, when the connector shoe is inserted between the bosses, and align the plurality of openings of the connector shoe and the connector base such that fluids can pass between the connector shoe and the connector base and the sealers prevent leaking. In another embodiment, the connector shoe comprises a regulation device connected to at least one opening. In another embodiment, the regulation device is a gauge.
Other features, advantages, and object of the present invention will become more apparent and be more readily understood from the following detailed description, which should be read in conjunction with the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the invention are discussed below with reference to the Figures. However, those skilled in the art will readily appreciate that the detailed description given here with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. For example, without limitation, it should be appreciated that those skilled in the art will, in light of the teachings of the present invention, recognize a multiplicity of alternate and suitable approaches, depending on the needs of the particular application, to implement the functionality of any given detail described herein, beyond the particular implementation choices in the following embodiments described and shown. That is, there are numerous modifications and variations of the invention that are too numerous to be listed but that all fit within the scope of the invention. Also, singular words should be read as plural and vice versa and masculine as feminine and vice versa, where appropriate, and alternative embodiments do not necessarily imply that the two are mutually exclusive.
The present invention will now be described in detail with reference to embodiments thereof as illustrated in the accompanying drawings.
Embodiments of the present invention provide liquid handling system containment devices that reduce cost of installation, simplify service and replacement of liquid handling systems, create protected space for liquid handling systems, and protect liquid handling systems from the elements such as, but not limited to, rain, snow, freezing, and heat. These embodiments also minimize vandalism by being out of site and having a secure lid. The lid in these embodiments may also be colored to minimize visibility of the containment device.
The preferred embodiment of the present invention is designed to hold a liquid handling system by the use of quick connect devices, enabling easy removal of the liquid handling system for service and replacement. No entrance into the vault is required. By servicing the liquid handling system components above ground, the need to enter the containment device is eliminated. Therefore, confined space is not an issue with the preferred embodiment, and not having to enter the vault eliminates hazardous gasses issues. Not entering the containment device also generally climinates clear area issues for electrical appliances needed, for example, without limitation, pressure switches, disconnects, junction boxes, breaker panels, etc.
FIGS. 1 , 2 , and 3 illustrate an exemplary vault assembly 20 for a liquid handling system containment device, in accordance with an embodiment of the present invention. FIG. 1 shows a front view; FIG. 2 shows a side perspective view, and FIG. 3 shows an exploded view. The present embodiment comprises vault assembly 20 that houses liquid handling system devices such as, but not limited to, pressure tanks, pumps, filters, etc., in a clean, safe place that is weather resistant, for example, without limitation, resistant to heat, freezing, rain, snow, etc. The present embodiment enables easy initial installation and easy future repair and maintenance.
In the present embodiment, vault assembly 20 is comprised of a molded or fabricated vault 8 of adequate construction to withstand soil pressures to prevent distortion or collapsing when buried underground up to a lid 1 . Vault 8 is preferably constructed of a plastic or galvanized steel, but may be constructed of various alternate materials such as, but not limited to, aluminum or other metals. Vault 8 houses a quick connect system and a liquid handling device 4 connected to the quick connect system. The top of vault 8 has a ridge that enables lid 1 to seal to vault 8 and areas adequate to fasten lid 1 to vault 8 with fasteners 2 for security and safety. Fasteners 2 are designed to make removal of lid 1 difficult, adding to security. Fasteners 2 may be, for example, without limitation, latches, hooks, or bolts passing through lid 1 and threaded into vault 8 , to secure lid 1 to vault 8 . Lid 1 may be constructed of molded plastic or fabricated metal dependant on traffic, security, and aesthetic needs.
Vault 8 comprises a bottom to prevent pests from entering and provisions for drainage that may be needed. A quick connect base 11 , the first half of the quick connect system, is attached to a supporting device 10 that is also attached to other areas of vault 8 to support the weight of the liquid handling system being installed in vault 8 . Quick connect base 11 is bolted or welded to vault 8 to hold quick connect base 11 square. Liquid handling device 4 connects to bracket 5 by means such as, but not limited to clamps or bolts. Bracket 5 holds the second half of the quick connect system, a quick connect shoe 6 , and holds quick connect shoe 6 inline with quick connect base 11 , assuring proper alignment and support of liquid handling device 4 . Liquid handling device 4 is installed or removed by a lifting pipe 3 that is installed on bracket 5 . In alternate embodiments a handle on liquid handling device 4 may be used for lifting liquid handling device 4 out of vault 8 . Liquid handling device 4 may be any device connected to a pumping system such as, but not limited to, a pump, tank, meter, filter, valving, etc.
In the present embodiment, when lifting liquid handling device 4 out of vault 8 , typical plumbing 7 is disconnected by quick connect shoe 6 and quick connect base 11 separating in a vertical direction. To install quick connect assembly with pumping device 4 into vault 8 , the user slides quick connect assembly with liquid handling device 4 into the cavity of vault 8 in a vertical direction and aligns alignment feature 17 which guides quick connect shoe 6 into quick connect base 11 , thereby enabling quick connect shoe 6 to enter quick connect base 11 and pressing down until bracket 5 and a base supporting bracket 10 touch. At this point, plumbing 7 is connected, allowing fluid to pass from liquid handling device 4 through plumbing 7 to quick connect through shoe 6 and base 11 and on to external plumbing 9 .
External plumbing 9 enables items inside of vault 8 to be connected to mainlines outside of vault 8 . In some embodiments, plumbing 7 may be modified to accept a miniature quick connector 7 a , as shown by way of example in FIG. 6 , which enables pressure regulation devices such as, but not limited to, gauges to be easily removed without removing liquid handling device 4 from vault 8 . In other embodiments these regulation devices may be plumbed in direct without a quick connect when the servicing of the item is not an issue for example without limitation, with a pressure release valve. Items such as, but not limited to, pressure regulating valves, gate valves, ball valves, pressure relief valves and similar devices may be installed in plumbing 7 and external plumbing 9 as needed. These items can be installed at manufacture, in shop, or in the field as needed.
FIG. 4 illustrates a side perspective view of an exemplary quick connect adapter from a liquid handling system containment device, in accordance with an embodiment of the present invention. In the present embodiment, the quick connect adapter comprises quick connect base 11 and quick connect shoe 6 . Quick connect base 11 is a device that accepts quick connect shoe 6 . Quick connect base 11 has a flat area that has on each edge a slotted perpendicular boss that holds and aligns holes in quick connect shoe 6 and holes in quick connect base 11 when properly installed. O-rings 6 a in quick connect shoe 6 provide sealing to allow fluid to pass from quick connect base 11 to quick connect shoe 6 without leaking. O-rings 6 a are set in a groove machined in quick connect shoe 6 . Connection to quick connect shoe 6 and quick connect base 11 is accomplished with connectors 12 allowing pipe connection for controlled flow. Connectors 12 connect quick connect shoe 6 to plumbing 7 and quick connect base 11 to external plumbing 9 , shown by way of example in FIGS. 1 , 2 , and 3 . Connectors 12 may be threaded or plain end to be soldered or welded. Plumbing 7 and external plumbing 9 are fitted with conventional plumbing fittings such as, but not limited to, copper, galvanized steel, or plastic, to accommodate various apparatuses as liquid handling device 4 . This plumbing may be done at the factory, on site, or in a shop.
FIG. 5 illustrates a side perspective view of an exemplary quick connector assembly from a liquid handling system containment device, in accordance with an embodiment of the present invention. In the present embodiment, quick connect shoe 6 and quick connect base 11 may be installed anywhere on bracket 5 and base supporting bracket 10 to accommodate various liquid handling devices. In alternate embodiments, more than one quick connect adapter may be installed if needed or desired. In some embodiments portions of the outer ring of bracket 5 may be cut away to facilitate clearance for items mounted on the wall of vault 8 during removal, for example, without limitation, controllers, switches, disconnects, J-boxes, etc.
FIG. 6 illustrates a side perspective view and an exploded view of an exemplary optional quick connect assembly for a regulating device, in accordance with an embodiment of the present invention. Some embodiments of the present invention may have a small quick connector 7 a , as shown by way of example in FIGS. 1 and 2 . Quick connector 7 a can be used to adapt pressure-regulating devices 28 to plumbing 7 and external plumbing 9 , shown by way of example in FIGS. 1 , 2 , and 3 . These pressure-regulating devices 28 may include, without limitation, pressure switches, gauges, transducers etc. Quick connector 7 a enables these accessory devices 28 to be removed and serviced without removal of the main device.
In some embodiments these accessory devices 28 may also be connected by a small quick connect adapter similar to the quick connect adapter, shown by way of example in FIG. 6 , connecting liquid handling device 4 to the plumbing of the vault assembly. This small quick connect adapter comprises a quick connect base 23 and a quick connect shoe 24 . Quick connect base 23 and quick connect shoe 24 slide together to allow fluid to flow through to the accessory devices 28 . O-rings 25 seal the connections between quick connect base 23 and quick connect shoe 24 to prevent leaking. O-rings 25 set in a grooves machined in quick connect shoe 24 . Pipe nipples 26 adapt the plumbing from quick connect shoe 24 to the accessory device 28 .
By constructing vault 8 from plastics or thin gauge metals, vault 8 can be delivered in a pickup truck or trailer and set into an existing ditch by one person, without lifting equipment or with minimal lifting equipment. Installation is very quick. The only water connections that require attention at installation are external plumbing 9 positioned outside of vault 8 below the freezing level. Vault 8 is designed to control fluids by minimizing or eliminating rainwater and groundwater from entering. However, caution must be used when installing vault 8 in high water tables. In these situations water removal means such as, but not limited to, drains, sump pumps, or holes may be used to drain or remove any fluids that enter vault 8 . Vault 8 is installed in the ground after a waterline ditch has been dug, and water lines are connected to plumbing 9 at this time. A typical installation of vault assembly 20 , according to the present embodiment, is as follows.
After the excavator digs ditches for vault 8 and lines, vault 8 is placed in the ditch. The ditch must be of adequate width and depth to enable vault 8 to be buried to the level of lid 1 at the point of installation. Water lines are then connected to external plumbing 9 at vault 8 . Liquid handling device 4 can be in vault 8 at this time or may be installed into vault 8 after backfilling. If liquid handling device 4 is to be installed after backfilling, the excavator then backfills the ditch. Liquid handling device 4 along with bracket 4 is lowered into vault 8 . Alignment feature 17 guides quick connect shoe 6 into quick connect base 11 , and quick connect shoe 6 and quick connect base 11 are aligned. Bracket 4 with Liquid handling device 4 is then pushed into place. If electrical is needed, the electrical system is wired at this point. Lid 1 and fasteners 2 are then installed. If liquid handling device 4 requires service, fasteners 2 and lid 1 are removed and bracket 5 with liquid handling device 4 is lifted out of vault 8 . Liquid handling device 4 may be serviced and then reinstalled into vault 8 as described above.
Liquid handling device 4 that is housed in vault 8 may be assembled at a factory, in a shop, or in the field by service personnel. In the present embodiment, all other components are comprised in vault 8 . Electrical connections are preferably performed by an electrician. Controllers and other items such as, but not limited to switches, disconnects, J boxes, etc. may be installed on a post, inside vault 8 , or inside other structures as preferred. Vault 8 has a plastic or metallic lid 1 that seals to vault 8 attached with fasteners 2 to supply security and safety. This design enables many different components to be installed in vault 8 , for example, without limitation, pumps, meters, filters, pressure tanks, etc. The physical size of vault 8 , quick connect shoe 6 , and quick connect base 11 , bracket 5 and base support bracket 10 can be changed to facilitate equipment of different sizes, for example, without limitation, larger tanks, pumps, filters, meters, etc. Special ordered systems can be built individually as needed.
Being able to install the vault assembly outside, according to the present embodiment, provides space saving in buildings where the liquid handling system is needed. However, in alternate embodiments, this vault assembly may be installed in the floor of structures if needed.
An embodiment of the invention may be configured to enable the component parts of the foregoing liquid handling device to be removable from the housing using the quick connect shoe 6 and base 11 mounted to the sidewall of Vault 8 without using brackets 5 an 10 as shown in FIG. 7 page 7 of 7. This solution functions best for small lighter system devices. A drawback of this solution is Quick connect shoe 6 and base 11 is not intended to suspend excessive weight of large devices. Also, the flex in the sidewall of the vault at mounting point can cause problems with the removal of the heavy devices. A support 21 has been added to minimize flexing issues in this configuration. Support 21 is attached to the plumbing 7 . Support 21 rests on bottom of vault 8 to help support weight of device 4 .
Having fully described at least one embodiment of the present invention, other equivalent or alternative means for implementing a containment device for a liquid handling system according to the present invention will be apparent to those skilled in the art. The invention has been described above by way of illustration, and the specific embodiments disclosed are not intended to limit the invention to the particular forms disclosed. The invention is thus to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the following claims. | A containment device for a liquid handling system is presented. The devise has a vault having a cavity, a closed bottom and an open top. A supporting device having a first half of a quick connect system connected to external plumbing is positioned in a lower portion of the cavity and secured to the vault to provide support for a weight of the liquid handling system. A bracket having a second half of a quick connect system connected to internal plumbing for the liquid handling system is configured to retain the liquid handling system, contact the supporting device when the bracket and liquid handling system is lowered into the cavity and mate the first second halves of the quick connect system allowing liquid to flow from the external plumbing to the internal plumbing. A lid is secured to the top for minimizing the intrusion of environmental elements into the vault. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a wavelength tunable laser and an optical device using the wavelength tunable laser. More particularly, the invention relates to a semiconductor laser capable of tuning a lasing wavelength over a wide range, an optical modulator using the semiconductor laser, and a wavelength-division multiplexing transmission system employing, as a light source, a semiconductor laser used for a wavelength-division multiplexing optical system for multiplexing a plurality of different signal light and transmitting the multiplexed signal.
One of the important techniques in a wavelength-division multiplexing optical system is management of a wavelength of a light source of each of a plurality of channels. In the present optical communication systems, in order to maintain the wavelength of the light source at a predetermined value, a wavelength monitor and means for stabilizing the wavelength of the light source by feedback are provided for each channel and a spare light source prepared for a failure is provided for each of all of the channels. The number of related electronic devices therefore increases according to the number of channels. It is also necessary to control each semiconductor laser so that its lasing wavelength is within a predetermined narrow wavelength band. It is consequently difficult to improve the manufacturing yield. Such issues interfere with the attempt to achieve miniaturization and reduction in cost of an optical transmission system and are significant issues in the case of further narrowing the interval between waves of channels or the case of increasing the number of channels.
On the other hand, there is an idea such that the lasing wavelengths necessary for a plurality of channels are covered by a single backup light source by using a lasing wavelength tunable semiconductor laser. In this case, a wavelength tunable semiconductor laser capable of easily and successively sweeping the lasing wavelength is necessary, but has not been realized until now.
In particular, in an optical multiplexing transmission of a long distance, it is necessary to realize the system in a form that an optical modulator is monolithically integrated by which chirping can be reduced. In a monolithic integrated light source in which an optical modulator is incorporated, by adjusting the temperature of the whole light modulator, the wavelength of a channel can be adjusted. Presently, however, the operating temperature range of the monolithic integrated optical modulator is as narrow as ±5 degrees centigrade. The width of the wavelength which can be swept in practice is therefore only about 0.5 nm.
FIG. 9 shows the configuration in cross section of a wavelength tunable semiconductor laser capable of easily and successively sweeping the wavelength, in which a heater electrode is attached to a conventional buried heterostructure semiconductor laser. (For example, a technique described in IEEE Photonics Technology Letters, Vol. 4, p. 321, 1992 can be mentioned as a wavelength-division multiplexing system light source of this kind). According to the technique, a heater layer is formed over an upper electrode of a buried heterostructure semiconductor laser via an insulating film to control the temperature of an active layer. As shown by arrows with thick lines, since the heat generated by the heater layer escapes into not only the active layer but also a buried layer, the active layer cannot be efficiently heated. It is therefore a problem that the wavelength tuning efficiency, that is, the wavelength fluctuation range per unit power in the wavelength tunable semiconductor laser is as low as 3.2 nm/W.
SUMMARY OF THE INVENTION
It is therefore a main object of the invention to realize a wavelength tunable laser capable of tuning a wavelength over a wide range by simple means.
It is another object of the invention to realize a wavelength-division multiplexing transmission system which achieves the object and is suitable for a long distance transmission by using the wavelength tunable laser.
In order to achieve the objects, a wavelength tunable laser according to the invention is formed by mounting a thin film heater layer over and/or on a side of an upper electrode of a ridge waveguide semiconductor laser on a semiconductor substrate. The ridge waveguide semiconductor laser is obtained by forming a waveguide constructing a semiconductor laser in a ridge shape on a semiconductor substrate including a light emitting layer. The cross section of the ridge can have a shape of rectangle, trapezoid, or the like. An inverse trapezoid (inverse mesa) shape in which the side in contact with the semiconductor substrate is narrower than the upper side is preferable.
One of optical devices according to the invention is an integrated optical device in which the wavelength tunable laser and an external optical modulator are integrated on a semiconductor substrate of the wavelength tunable laser.
Further, another optical device according to the invention constructs a wavelength-division multiplexing transmission system for multiplexing light signal of a plurality of channels of different wavelengths and transmitting the light signal through a light transmission line. One or more wavelength tunable lasers are used as spare light source(s) of the plurality of light sources of the plurality of channels. When one of the light sources of the channels becomes faulty or the like and has to be replaced, the spare light source is allowed to operate and its wavelength is made coincide with the wavelength of the light source of the channel to be replaced by using the wave tuning function of the wavelength tunable laser.
The wavelength tunable laser of the invention enables the heat generated by the thin film heater to be efficiently applied to the light emitting part of the semiconductor laser. A monolithic integrated device is formed by combining the wavelength tunable laser with an optical modulator to thereby provide each of many optical devices such as a wavelength-division multiplexing transmission system with the effective means.
These and other objects, features and advantages of the present invention will become more apparent in view of the following description of the preferred embodiments in conjunction with accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view showing the structure of a monolithic integrated optical device as an embodiment of a wavelength tunable laser according to the invention.
FIG. 1B shows an enlarged portion of FIG. 1 A.
FIG. 2 shows the result of measurement of the wavelength tuning characteristic of the wavelength tunable laser according to an embodiment of the present invention.
FIG. 3A is a perspective view showing the structure of a monolithic integrated optical device constructing an optical modulator as an embodiment of an optical device using the wavelength tunable laser according to the invention.
FIG. 3B shows an enlarged portion of FIG. 3 A.
FIG. 4A is a perspective view showing the structure of a monolithic integrated optical device constructing an optical modulator as an embodiment of an optical device using the wavelength tunable laser according to the invention.
FIG. 4B shows an enlarged portion of FIG. 4 A.
FIG. 5 is a system configuration diagram showing the configuration of a wavelength-division multiplexing optical system to which a wavelength tunable laser according to the invention is applied.
FIG. 6 is a block diagram showing the configuration of the main part of FIG. 5 .
FIG. 7 is a perspective view for explaining an embodiment of a spare light source corresponding to a spare light source 507 in FIG. 6 or the like.
FIG. 8 is a block diagram showing another embodiment of a wavelength-division multiplexing transmission system.
FIG. 9 is a cross section of a wavelength tunable laser which is a conventionally known buried semiconductor laser.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
FIG. 1A is a perspective view showing the configuration of a monolithic integrated optical device as an embodiment of a wavelength tunable laser according to the invention. The cross sectional configuration of the main part of the embodiment is shown in an enlarged diagram FIG. 1 B.
In the wavelength tunable laser, a buffer layer 102 and an active layer 103 are formed on a semiconductor substrate 101 and a ridge waveguide which includes a cladding layer 106 and a cap layer 107 and has an inverse mesa shape is formed. On the active layer 103 , polyimide as a nonconductor 115 is formed via SiO 2 on both sides of the ridge waveguide. Further, an upper electrode 108 of a semiconductor laser is formed on the ridge waveguide and a thin film heater 110 is mounted over the upper electrode 108 via an insulating film 109 .
An embodiment of a method of fabricating the wavelength tunable laser will be described hereinbelow. On an n type ( 100 ) InP semiconductor substrate 101 , 1.0 μm of an n type InP buffer layer 102 , the active layer 103 , and 0.02 μm of a first p type InP cladding layer 104 are sequentially deposited by metalorganic vapor-phase epitaxy. The active layer 103 has 0.05 μm of an n type InGaAsP lower guide layer (composition wavelength of 1.10 μm), a multiple quantum well layer of 5 cycles (a well layer made of InGaAsP having a thickness of 6.0 nm and compressive strain of 1% (composition wavelength of 1.70 μm) and a barrier layer made of InGaAsP having a thickness of 10 nm (composition wavelength of 1.15 μm)) and 0.05 μm of an upper guide layer made of InGaAsP (composition wavelength of 1.15 μm). The wavelength of light emitted from the multiple quantum well active layer 103 is about 1.56 μm.
A grating 105 of uniform cycles of 241 nm is formed on the whole face of the substrate by holographic photolithography and wet etching. The depth of the grating is about 50 nm. Subsequently, 1.7 μm of the second p type InP cladding layer 106 and 0.2 μm of a highly doped p type InGaAs cap layer 107 are formed by metalorganic vapor-phase epitaxy.
Subsequently, a process is performed to obtain an inverse-mesa ridge waveguide type laser structure having the width of about 2.0 μm and, after that, the upper electrode 108 is formed. The upper electrode 108 for laser driving is patterned and the silicon oxide film 109 having a thickness of 200 nm is formed on the entire face. Further, the platinum thin film heater 110 having a width of about 10 μm and a thickness of 300 nm is formed only over the ridge waveguide by electron beam evaporation, photolithography, and ion million. Au heater electrode pads 114 for connection are connected to both ends of the platinum thin film heater 110 .
Finally, after opening a window in the upper electrode 108 for laser driving, a lower electrode 111 is formed. The resultant is cut by a cleavage process into devices each having a length of d=400 μm, a low reflecting film 112 of about 1% of reflectance is formed on the front end face of the device and a high reflecting film 113 of about 90% of reflectance is formed on the rear end face by a known method.
A distributed feedback semiconductor laser device in a 1.55 μm band fabricated by the above fabricating method is mounted on a heat sink (not shown) using a silicon carbide material and the upper electrode 108 for laser driving and the heater electrode are wired.
FIG. 2 shows the result of measurement of the wavelength tuning characteristic of the wavelength tunable laser according to the embodiment. In the graph, the lateral axis denotes power consumption (mW) of the heater 110 and the vertical axis denotes a change value (nm) of the wavelength. In the graph, black dots indicate the embodiment and blank dots show the conventional technique shown in FIG. 9 . The measurement is carried out under the condition that the heat sink temperature is set at 20 degrees centigrade and the heater current passing through the heater 110 is changed in a range from 0 to 100 mA. As understood from the measurement result, by changing the heater current within the range from 0 to 100 mA, the wavelength tuning range of 5 nm or larger is obtained. In this case, the wavelength tuning efficiency of about 10 nm/W that is about 10 times as high as the conventional one is obtained. Since the temperature coefficient of the lasing wavelength of the laser is 0.11 nm/deg., the temperature of the laser active layer is heated to 20 to 57 degrees centigrade. In this case, the laser driving current necessary for a constant output of 10 mW changes from 50 mA to 70 mA. An increase is therefore suppressed to only 20 mA.
On the other hand, the longitudinal mode of the distributed feedback laser during sweeping of the wavelength by the current is stable, so that complete continuous wavelength sweeping is realized without mode hopping since the reflectance of the laser cavity uniformly changes by the heating and, in principle, there is no change in the longitudinal mode.
In the embodiment, as mentioned above, since the characteristic fluctuation at the time of high temperature is smaller as compared with the conventional buried hetero structure semiconductor laser shown in FIG. 9, the ridge waveguide structure semiconductor laser has an advantage such that the laser characteristic deterioration at the time of heating of the heater is a little. Since heat generated by the heater 110 does not easily escape to the polyimide portion 104 , the active layer can be efficiently heated via the ridge section. Consequently, the wavelength tuning operation can be realized with a smaller amount of power consumption.
The wavelength tunable laser on which the heater having the multiple quantum well active layer made of InGaAsP is mounted has been described in the embodiment. When the laser has an active layer made of another material such as InGaAlAs or GaInNAs having an excellent characteristic at high temperature, the high temperature characteristic of the active layer is more excellent than that of the InGaAsP material laser of the embodiment. Consequently, the wavelength sweep can be realized over a wider range.
In the structure of the embodiment, by passing the current to the heater electrode, the laser active layer is heated to change the reflectance. Thus, the lasing wavelength of the distributed feedback laser can be changed over a wide range.
Embodiment 2
FIG. 3A is a perspective view showing the configuration of a monolithic integrated optical device as another embodiment of the wavelength tunable laser according to the invention. The cross sectional configuration of the main part of the embodiment is shown in an enlarged diagram FIG. 3 B. The different point from the embodiment shown in FIGS. 1A and 1B is the position of the heater electrode. In the second embodiment, a heater electrode 210 is formed over an active layer 203 via a silicon oxide film 209 on a side of the ridge waveguide. The ridge waveguide and the heater electrode 210 are provided so as to have a predetermined gap and a nonconductor is removed. The other structure is substantially the same as that of FIGS. 1A and 1B. Specifically, 1.0 μm of an n type InP buffer layer 202 , an active layer 203 , and a first p type InP cladding layer 204 are sequentially formed on an n type ( 100 ) InP semiconductor substrate 201 .
The device has a grating 205 formed on the entire face of the substrate, a second p type InP cladding layer 206 , a highly doped p type InGaAs cap layer 207 , an inverse mesa ridge guide laser structure, an upper electrode 208 , and a silicon oxide film 209 . Au heater electrode pads 214 for wiring are connected to both ends of the platinum thin film heater 210 . A low reflecting film 212 of reflectance of about 1% is formed on the front end face of the integrated device and a high reflecting film 213 of reflectance of about 90% is formed on the rear end face. The embodiment has also the inverse mesa ridge waveguide shown in FIGS. 1A and 1B and can realize the wavelength tuning characteristic in a manner similar to the first embodiment.
Embodiment 3
FIG. 4A is a perspective view showing the configuration of a monolithic integrated optical device constructing an optical modulator as an embodiment of an optical device using the wavelength tunable laser according to the invention. The cross sectional configuration of the main part of the embodiment is shown in an enlarged diagram FIG. 4 B.
In the embodiment, a wavelength tunable laser of the operating principle similar to that of the embodiment 1 and an electro-absorption optical modulator are monolithic integrated. On an n type ( 100 ) InP semiconductor substrate 301 , an n type InP buffer layer 302 , an active layer 303 , and a first p type InP cladding layer 104 are sequentially deposited. The active layer 303 comprises 0.05 μm of an n type InGaAsP lower guide layer (composition wavelength of 1.10 μm), a multiple quantum well layer of 5 cycles (a well layer made of InGaAsP having a thickness of 6.0 nm and compressive strain of 1% (composition wavelength of 1.70 μm) and a barrier layer made of InGaAsP having a thickness of 10 nm (composition wavelength of 1.15 μm), and 0.05 μm of an upper guide layer made of InGaAsP (composition wavelength of 1.15 μm). A grating 305 of uniform cycles of 241 nm is formed on the whole face of the substrate. Subsequently, a second p type InP cladding layer 306 and a highly doped p type InGaAs cap layer 307 are formed. Further, a process is performed to obtain an inverse mesa ridge waveguide laser structure having a width of about 2.0 μm and, after that, an upper electrode 308 is formed. On the upper electrode 308 , a silicon oxide film 309 is formed on the entire face. A platinum thin film heater 310 is formed only over the ridge waveguide. Au heater electrode pads 314 for connection are connected to both ends of the platinum thin film heater 310 . After opening a window in the upper electrode 308 for laser driving, a lower electrode 311 is formed. A low reflecting film 312 of about 1% of reflectance is formed on the front end face of the device and a high reflecting film 313 of about 90% of reflectance is formed on the rear end face. An enlarged diagram shows a cross section of the semiconductor layer of the main part taken along line X-X′.
In the embodiment, an electro-absorption optical modulator is formed on the InP semiconductor substrate 301 . The interval of 150 μm or more is provided between the wavelength tunable laser and the electro-absorption optical modulator. It is designed so that heat applied into the laser at the time of tuning the wavelength does not reach the optical modulator. In a manner similar to the first embodiment, the basic lateral structure is a known inverse mesa ridge waveguide laser in which polyimide is embedded such that a nonconductor 315 such as polyimide is formed on both sides of the ridge waveguide. According to the third embodiment, when the oscillation wavelength is 1550 to 1554 nm and the current of heating is changed from 0 to 100 mA, 4 nm of the wavelength tuning width is obtained. When the wavelength is tuned, a stable long distance transmission characteristic is obtained at 10 gigabits per second within the wave sweeping range of 4 nm since the change in the chirping characteristic of the electro-absorption optical modulator is slight in the wavelength range of about 4 nm.
Embodiment 4
FIGS. 5 and 6 are a system configuration diagram and a diagram showing the configuration of the main section of a wavelength-division multiplexing transmission system using the wavelength tunable laser according to the invention.
Light signals of a plurality of channels whose wavelengths are multiplexed, which are generated by a wavelength-division multiplexing transmission system 501 according to the invention are amplified by a fiber amplifier 502 and the amplified signals are transmitted through an optical fiber 503 for transmission and demodulated by an optical receiver 504 via an optical amplifier on the receiving side. As necessary, one or a plurality of optical amplifiers 502 for relay are provided in some midpoints in the optical fiber 503 .
The wavelength-division multiplexing transmission system 501 is formed as a monolithic integrated device having optical devices of a plurality of light signal sources 505 of different wavelengths of a plurality of channels ch. 1 to ch. 32 , a spare light source 507 , a Mach-Zehnder type optical modulator 508 for optical modulating an output of the spare light source 507 , and an optical multiplexer 506 for multiplexing output light of the light signal sources 505 and the modulator 508 . The wavelength set in the light signal source 505 is 1534.25 nm to 1558.98 nm and the wavelength interval is set to 100 GHz. A single spare light source 507 covers the entire wavelength range from 1534.25 nm to 1558.98 nm.
The light output of the spare light source 507 is led to the Mach-Zehnder type optical modulator 508 which is a single waveguide optical modulator and is made of lithium niobate, and subjected to high-speed optical modulation. Since the modulation characteristic hardly fluctuates according to the operation wavelength in the Mach-Zehnder type optical modulator 508 , laser beams of different wavelengths from the spare light source 507 are modulated with the same chirping characteristic. According to the embodiment, when a fault occurs in any of the main light sources 505 of 32 channels, by setting the wavelength of the spare light source 507 to the wavelength of the faulty light source, the function of the wavelength-division multiplexing transmission system is recovered at high speed. All of the channels can be backed up by the single spare light source 507 , the single Mach-Zehnder type optical modulator 508 , and a single driver. Consequently, as compared with the conventional configuration in which spare parts are prepared for each of the channels, the miniaturization of the system and the cost reduction are greatly improved.
Embodiment 5
FIG. 7 is a perspective view for explaining an embodiment of a spare light source corresponding to the spare light source 507 in FIG. 6 or the like. In the embodiment, eight distributed feedback semiconductor lasers 701 are monolithic integrated on a semiconductor integrated substrate 705 . Output light of the semiconductor lasers 701 are converged to an outgoing waveguide 704 by a known optical multiplexer 702 integrated on the same substrate 705 . A semiconductor light amplifier 703 is connected to the outgoing waveguide 704 to compensate a multiplexing loss. The oscillation wavelength of each of the eight distributed feedback semiconductor lasers 701 is set to a range from 1530 to 1562 nm and the ranges are set at intervals of 4 nm by controlling a grating cycle and a gain peak wavelength of each of the lasers 701 in accordance with a known method. The configuration of the semiconductor laser 701 is according to the embodiment shown in FIG. 1 . When the carrier temperature of the semiconductor laser 701 was set to 20 degrees centigrade and the current of heating was changed in a range from 0 to 100 mA, the wavelength tuning width of 4 nm was realized.
Embodiment 6
FIG. 8 is a block diagram showing another embodiment of the wavelength-division multiplexing transmission system. In the embodiment shown in FIG. 6, only one spare light source 507 is provided. In the sixth embodiment, a plurality of channels ch. 1 to ch. 33 are divided into eight groups 805 each having four channels of close wavelengths and spare light sources 801 to 808 are provided for the eight groups, respectively. The other configuration and operation are similar to those of FIG. 6 .
The wavelength tunable laser according to the invention can realize the wide wavelength tuning range and the wave tuning efficiency a few times as high as that of the known conventional buried hetero structure semiconductor laser by the simple configuration of using the ridge structure semiconductor laser. By monolithic integrating the wavelength tunable laser and the optical modulator and assembling the integrated device to a communication system, a high-reliability high-quality wavelength-division multiplexing transmission system can be realized. Further, a very reliable optical transmitter capable of continuously tuning the wavelength of a transmission signal can be easily realized at low manufacturing cost. | In order to form a wavelength tunable laser capable of tuning a wave over a wide range by simple control means, a thin film heater is mounted either over an upper electrode of a ridge waveguide semiconductor laser having ridge waveguides on a semiconductor substrate or over the semiconductor substrate and on both sides of the ridge waveguide with a gap of a few μm. By controlling a current passed to the thin film heater, the oscillation wavelength of the semiconductor laser is tuned. In the case where the thin film heater is mounted over an upper electrode of a ridge waveguide, a nonconductor is formed on both sides of the ridge conductor to more efficiently enable heat from the heater to reach an active layer of the ridge waveguide more efficiently. | 1 |
BACKGROUND OF THE INVENTION
Poultry, beef, and fish processing is an extensive industry. Every year, for example, approximately four billion chickens are processed and sold in the United States alone. Unfortunately, mass production techniques make processing plants prime breeding grounds for food poisoning bacteria such as Salmonella and Escherichia. "According to the federal Food Safety & Inspection Service in Washington, D.C., about 37 percent of all chicken meat sold in the United States is infected with Salmonella. The Center for Disease Control in Atlanta estimates that Salmonella, which can cause severe stomach pains and even typhoid fever, kills about 1,000 people a year and causes another 35,000 to be hospitalized." "Microbiologist hatches test kit for salmonella", San Francisco Business Times, (Jul. 6, 1987) p. 13.
In the poultry industry, chickens are shipped to a processing plant where they are killed, defeathered, and eviscerated along rapidly moving disassembly lines. Assembly line workers commonly wear protective steal mesh gloves to guard against accidental injuries from knives which are used during product cut-up and evisceration. During processing, bacteria and other contaminants associated with the chickens inevitably are transmitted to these gloves. As a result, the U.S.D.A. has developed information concerning bacteria concentration levels for safe, sanitary assembly line operations. These bacteria levels are measured according to a bacteria plate count which signifies the number of bacterial colonies per square inch. It is currently understood that a bacteria plate count of one hunted or less is considered sterile and thus acceptable. The food processing industry has been attempting to develop an effective approach to mitigate bacterial dissemination and clean soiled gloves in a manner commensurate with such governmental standards.
In multi-shift plants, gloves typically are cleaned at the end of a given shift for subsequent use. If adequate cleaning has not occurred, process workers may start a shift with gloves that already have an unacceptable plate count. Thereafter, during the shift, every chicken, from the first one handled, may be infected with bacteria. As an example of the potential for bacterial dissemination, larger processing plants may run assembly lines at ninety chickens per minute with a chain of processing personnel, one person handling every third bird. By the end of a shift, a single processor may come in contact with hundreds of birds and have a glove contamination at a plate count level of half a million or more. Moreover, each bird may be handled by as many as ten different processors. As a result, cross contamination of bacteria among chickens inevitably occurs. The resultant need for clean gloves during processing is apparent.
In the poultry industry, there presently is no uniformly practiced method for adequately cleaning gloves to meet the governmental requirements. One method for cleaning is to use high pressure water from a spray wand. The gloves are placed on the plant floor, frequently already contaminated, secured under a foot, and manually sprayed with high pressure water to remove flesh and other particles. This method has proven less than effective in that spraying with high pressure water alone merely removes larger, visible contaminants. Micro-analysis testing reveals that the gloves still have a high bacteria plate count concentration, often in the hundred thousand range. If the gloves are used after spraying, the bacteria not washed out will continue to multiply exponentially with time, contaminating the production system. The wand cleaning method is additionally inefficient in that it requires several minutes to spray and clean each glove, which must be done one at a time. Preferably, glove cleaning should be carded out during a given shift, for example, during breaks as well as following it. Unfortunately, those breaks are of such a short duration as to preclude such desirable practices. Additionally, the number of gloves involved is substantial; larger plants employ four to five hundred gloves used in a single shift. Another cleaning approach involves soaking the gloves in a chemical sanitizing solution. This process, however, typically requires overnight treatment which makes it impractical for use with multi-shift plants requiring rapid cleaning, as for example during a five minute break or between shifts.
In another approach, a washer has been employed which operates much like a conventional, household dishwasher. Contaminated gloves are placed upright on open ended forks which slowly cycle through a washing chamber. Inside the chamber, the gloves are blasted by high pressure cold water jets. Designs heretofore offered to industry have been found to be unacceptable because of the difficulties of cleaning the machines themselves, the entanglement of the gloves within conveyor assemblies, limited plant water supplies, cross contamination of gloves during the cleaning process, unacceptable plate count levels, and the like.
Other washers combine soap and hot water cleaning cycles. These devices require a separate rinsing chamber and washing chamber which greatly adds to manufacturing and maintenance costs. Still other devices have used anhydrous ammonia as a sterilizing agent (400 ppm) which have experienced severe waste disposal problems.
Effective cleaning necessarily involves cleaning the glove tips. During processing, the finger tips are in frequent pressure contact with chicken parts and, as a result, are heavily contaminated with flesh and the like. A washer should be designed to remove the contaminants in these concentrated areas to produce a glove with a safe bacterial level.
An effective washer should not only lower plate count levels, but also be designed for effective periodic cleaning. In this regard, bacteria removed from the gloves during washing tends to accumulate and grow in the washing chamber. Crevices, nooks, protrusions, and any other non uniform surface act as pockets where bacteria may grow. As the gloves are being cleaned in the washing chamber, they are often exposed to contamination from such bacteria pockets, for example through splashing. Cross contamination between dirty gloves entering the chamber and clean ones leaving may also occur. As another design consideration, washers are periodically cleaned to remove bacteria, such as that accumulating in the pockets. Prior washers, have not been adequately designed for easy disassembly. Typically, extensive time and effort is required to access interior locations for cleaning or maintenance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of apparatus configured according to the invention;
FIG. 2 is a left side view of the apparatus of FIG. 1;
FIG. 3 is a front view of the apparatus of FIG. 1;
FIG. 4 is a rear view of the apparatus of FIG. 1;
FIG. 5 is a top view of the apparatus of FIG. 1;
FIG. 6 is a sectional view of apparatus according to the invention taken through the plane 6--6 shown in FIG. 3;
FIG. 7 is a partial sectional view taken through the plane 7--7 shown in FIG. 6;
FIG. 8 is a sectional view taken through the plane 8--8 shown in FIG. 6;
FIG. 9 is a sectional view taken through the plane 9--9 shown in FIG. 6;
FIG. 10 is a partial sectional view taken through the plane 10--10 shown in FIG. 9;
FIG. 11 is a partial sectional view taken through the plane 11--11 shown in FIG. 9;
FIG. 12 is a partial sectional view taken through the plane 12--12 shown in FIG. 10;
FIG. 13 is a sectional view taken through the plane 13--13 shown in FIG. 6;
FIG. 14A is a plan view of a portion of a glove mount employed with the apparatus of the invention;
FIG. 14B is a sectional view taken through the plane 14B--14B shown in FIG. 14A;
FIG. 15 is a partial sectional view taken through the plane 15--15 shown in FIG. 13;
FIG. 16 is a partial sectional view taken through the plane 16--16 shown in FIG. 13; and
FIG. 17 is a schematic diagram showing fluid delivery and electrical circuitry employed with the apparatus of FIG. 1.
SUMMARY
The present invention is addressed to apparatus for cleaning industrial safety apparel such as wire mesh gloves with efficiency and speed. Gloves employed in processing meat products such as chickens are cleaned effectively within a time interval permitting more frequent cleaning, for example, during short work breaks in the course of a given shift and with an apparatus which is fabricable at practical cost levels.
Cleaning is carried out within a confined chamber into which a conveyor assembly extends carrying gloves upon uniquely elevated glove mounts. Movement of the glove mounts is along a conveyor locus of movement extending from an access deck assembly. The height of the glove mounts is effective to avoid glove entanglement with moving components of the apparatus. To achieve ingress and egress from the containment chamber with the elevated glove mounts, a unique curtain assemblage formed of very thin plastic and with varying side-to-side overlapping is employed. In this regard, a very small overlap is employed at the level of the gloves themselves where high pressure nozzle outputs are not present. Correspondingly, a greater overlap of entrance and exit curtains is employed below the level of the glove where potentials for spray excursions are present. While within the cleaning chamber for a relatively short residence interval, the gloves are subjected to high pressure spraying of chlorinated water expressed from rotating nozzles at an elevated temperature of about 100° F. Such elevated temperature evokes a flesh cooking activity facilitating its removal, while chlorination in amounts within a range of about 150 to 200 pans per million (ppm) facilitates flesh removal while destroying bacteria. Cross contamination of clean gloves from dirty gloves is avoided through a ramp developed enhancement of removal of contaminated cleaning fluid from the chamber and with a unique exit and entrance separation structuring. To facilitate the removal of contaminant from the tips of gloves, the axis of rotation of the cleaning nozzles is offset slightly from the axis of rotation of the locus of movement of the glove mounts within the chamber. This evokes an undulation or relative movement between the nozzles dedicated to glove tip cleaning and the tips of the gloves themselves. The utilization of hot water along with cold water from the water supply of a given processing plant assures an adequate water supply to the instant apparatus for application within plants with relatively limited water availability.
The important aspect of cleaning the apparatus, for example during cleaning shifts, is enhanced through the utilization, for example, of removable doors or panels from two sides of the containment chamber. This exposes the interior regions of the cleaning chamber for facile access by cleaning personnel. To remove these light weight doors or panels, such cleaning personnel need only lift them a few inches and slide them sideways. Reinstallation of the doors is carried out simply following the reverse procedure. Access further is achieved through a pivoting front deck assembly, not requiring deck lid removal to simplify a pivoted repositioning. Cleaning further is enhanced through the employment of the noted sloping ramp beneath the conveyor assembly which extends under front access deck components. This ramp assembly supports a number of components including bearing blocks for rotating shafts. These bearing blocks are formed of a plastic material immune to chemical attack and which incorporate an O-ring attachment with the ramp surface to minimize the amount of potential contaminant cavity regions.
Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter.
The invention, accordingly, comprises the system and apparatus possessing the construction, combination of elements, and arrangement of parts which are exemplified in the following disclosure.
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction with the accompanying drawings.
DETAILED DESCRIPTION OF THE INVENTION
The apparatus of the present invention functions to carry out the cleaning of industrial gloves and the like to an extent wherein contaminant removal and associated bacterial removal achieves about a 99% reduction in the plate count levels for each machine pass or cycle. This is accomplished without cross-contamination between emerging clean and entering contaminated gloves and within a cleaning cycle of duration which permits the gloves of a typical production shift to be cleaned during an employee break in the course of a given production shift. Of corresponding importance, the apparatus is accessible for cleaning by cleaning personnel during a cleaning shift or time interval following normal production shifts. It is during these intervals of time that the cleaning personnel must have facile access to all aspects of the machine regions to be cleaned such that cleaning can be carried out effectively without leaving bacterial pockets and the like. In this respect, pockets or bolted connections and the like which may create bacterial collecting regions are avoided and the system almost achieves a "self-cleaning" aspect in the normal course of its operation. Additionally, access to the regions of the apparatus to be cleaned is substantially improved along with a lessening of the physical requirements for achieving such access. These features are achieved utilizing the typically limited water supplies available in a production environment and at cost levels which are practical.
Referring to FIG. 1, a pictorial representation of the apparatus for removing flesh containing contaminants from protective gloves is shown generally at 10. The apparatus 10 includes a lower support assembly 12 intended to be placed upon a plant floor surface. For this purpose, leveling feet, three of which are shown at 14-16, are provided to assure proper leveling to achieve optimum fluid flow. The fourth of such leveling feet is shown at 17 in FIG. 4. Lower support assembly 12, in turn, supports a containment chamber represented generally at 22 which is depicted having an upper portion represented generally at 24, a lower portion shown generally at 26, a forward portion 27 and two side portions, one of which is seen in general at 28 in the present figure, the opposite side of which is seen at 30 in FIGS. 3-5. Additionally supported upon the lower support assembly 12 and adjacent the containment chamber 22 forward portion 27 is an access deck assembly represented generally at 32. Deck assembly 32 includes a deck cover 34 which is hinged to the lower support assembly 12 at hinge 36. Centrally within the assembly 32 there is formed an opening 38 having a U-shaped periphery which functions to access the entrance region of a conveyor assembly represented generally at 40.
Conveyor assembly 40 serves to support a sequence of stainless steel glove mounts represented generally at 42. Gloves as at 44 are drawn over the mounts 42 which, inturn, are positioned for movement by the conveyor assembly 40 into containment chamber 22, whereupon the gloves undergo high pressure spray cleaning. Certain of the gloves 44 are seen to have a wrist securement strap or component 46 which will tend to hang downwardly as the gloves are moved along a conveyor locus defined by the conveyor assembly 40. Each of the glove mounts 42 is formed having a rod support component 48 into which a relatively high, fork-shaped glove support 50 is removably inserted. Such a fork-shaped glove support 50 is seen without a mounted glove 44 in FIG. 2. Glove supports 50 are removed by personnel for the purpose of inserting them within a glove 44, whereupon they are reinstalled within the rod support components 48 as the personnel stand before the access deck assembly 32. Generally, the glove mounts 42 are configured such that the tip regions 52 of gloves 44 are about 25 inches above the conveyor assembly. This relatively elevated configuration assures that no entanglement occurs between such components as the straps 46 and the conveyor assembly 40. However, accommodation is required for the greater bending moments imposed upon the glove mounts 42 occasioned during the entrance to and exit from containment chamber 22.
Considering the entrance of the sequence of glove 44 carrying glove mounts 42 into the containment chamber 22, it may be observed that the forward portion 27 of chamber 22 is configured having a flat forward door assembly represented generally at 54 and comprised of a flat transparent polymeric front door 56 which is slidably received within two spaced-apart, vertically disposed channel-defining forward door tracks 58 and 60. Slidable movement of the front door 56 is facilitated by two stainless steel, D-shaped handles 62 and 64.
Looking additionally to FIG. 3, it may be observed that the central portion of front door 56 is configured to accommodate an entrance curtain assembly represented generally at 66 and an oppositely disposed exit curtain assembly represented generally at 68. Curtain assemblies 66 and 68 are designed for the purpose of protecting the user of apparatus 10 from the high pressure sprays and contaminant carrying fluid splashes extant within containment chamber 22. They also are designed to accommodate for the earlier-noted relatively elevated stature of the glove mounts 42 and the bending moments associated with their movement into and out of chamber 22. This is achieved through the utilization of a very thin, flexible polymeric material, for example polyurethane, having a thickness of about 0.060 inch in combination with a selective curtain overlap arrangement. In this regard, entrance curtain assembly 66 includes an inwardly facing vertically oriented flexible polymeric sheet 70 having a length extending from a bottom location 72 (FIG. 3) adjacent conveyor assembly 40 to an upper location 74 positioned slightly above the tip region 52 of a glove 44 when mounted upon glove mount 42. Polymeric sheet 70 is attached to the forward face of front door 56 by a stainless steel strap 76.
The opposite side of entrance curtain assembly 66 is configured having two flexible polymeric sheets which selectively overlap polymeric sheet 70. In this regard, the lower one of these polymeric sheets 78 extends from bottom location 72 to a top location or elevation 80 adjacent to and spaced below a glove 44 when supported upon a glove mount 42. Lower polymeric sheet 78 overlaps the corresponding lower portion of polymeric sheet 70 by an amount effective to protect the user from the high pressure sprays extant within containment chamber 22. Generally, for the thin polymeric material involved, an overlap of about 1 inch is desirable. This 1 inch overlap also may be flexed rearwardly by the upstanding rod portion 368 of fork-shaped glove support 50. Extending above lower polymeric sheet 78 from top location 80 to upper location 74 is an upper polymeric sheet 82 of the same thickness but dimensioned to overlap the corresponding upper portion of polymeric sheet 70 by a much smaller amount, for example, less than about 3/8 inch and preferably about 1/4 inch. This lesser overlap facilitates the flexing of the curtain components by the glove and glove mount assembly as it is pushed therethrough by the conveyor assembly 40. Attachment of both lower polymeric sheet 78 and upper polymeric sheet 82 is by a stainless steel strap 84 which is attached, in turn, to an inwardly disposed separation structure 292 (FIG. 6) of chamber 22. The lesser overlap provided by polymeric sheet 82 becomes available inasmuch as high pressure fluids are not directed toward it and, thus, it is required to contain only indirectly impinging fluids flashing from glove mounts 42 and associated gloves 44.
Exit curtain assembly 68 is similarly structured having an inwardly facing flexible polymeric sheet 86 which extends from bottom location 72 to upper location 74 and which is attached to front door 56 by a stainless steel strap 88. Polymeric sheet 86 is of the same thickness as sheet 70 and cooperates with a lower polymeric sheet 90 which is integrally formed with sheet 78 and attached to a shield structure 292 within chamber 22 by strap 84. As before, a one-inch overlap is provided by the sheet 90 for the purpose of accommodating higher pressure sprays and which is engaged by the lower portion of glove mounts 42 as they exit from containment chamber 22. Above polymeric sheet 90 there is positioned an upper polymeric sheet 92 dimensioned identically and formed integrally with corresponding polymeric sheet 82 and extending from the earlier-noted top location or elevation 80 to upper location 74. As before, the overlap provided by upper polymeric sheet 92 is less than about 3/8 inch and preferably about 1/4 inch to permit facile egress of glove retaining glove mounts while confining splashing fluids to the entrance of chamber 22. Sheet 92 is fixed with sheet 82 to internal chamber structure by strap 84.
To facilitate the cleaning of chamber 22 during cleaning shift operations, the front door assembly 54 is configured to be removed with minimum physical effort. Initially, the front door 56 is formed of a lighter polymeric material, for example lexan having a thickness of about 1/4 inch. FIG. 3 reveals that the door 56 has a generally T-shaped side edge configuration with lower side edges 94 and 96 being laterally spaced apart so as to be received within mutually inwardly facing channel-like openings of respective tracks 58 and 60.
Lower side edges 94 and 96 extend to respective upper side edges 98 and 100 which are spaced apart a greater distance. In this regard, the edges 98 and 100 fit snugly within the channels of tracks 58 and 60 such that slidable movement of them within the tracks is vertical and not horizontal. Correspondingly, the slidable movement of edges 94 and 96 within respective tracks 58 and 60 is both vertical and horizontal. With this arrangement, only a minimum of effort is required on the part of cleaning personnel to remove the front door 56. This is carried out by lifting it slightly to slide it upwardly within tracks 58 and 60 to an extent represented by the corresponding vertical extent of upper side edges 98 and 100. Door 56 then may be slid laterally in either direction an amount sufficient to clear tracks 58 and 60. With the arrangement, only a limited amount of lifting is called upon on the part of cleaning personnel to effect door removal and reinsertion.
The effective cleaning of chamber 22 also requires a high degree of access thereto that all pockets which possibly could contain bacteria promoting contaminants can be cleaned. To accommodate for this need, apparatus 10 incorporates a side door assembly which is represented in general in FIGS. 1 and 2 at 110. Side door assembly 110 is formed in similar fashion as front door assembly 54. In this regard, the assembly 110 includes a flat side door 112 formed of polymeric material such as lexan having a thickness of about 1/4 inch. Attached to the lower portion of door 112 are two D-shaped stainless steel handles 114 and 116. Looking additionally to FIG. 8, door 112 is slidably received within internally disposed channel shaped tracks 118 and 120. FIG. 2 reveals that the side door 112 is configured having a generally T-shaped side edge configuration having laterally spaced-apart lower side edges 122 and 124 which are both horizontally and vertically slidable within respective tracks 118 and 120. Edges 122 and 124 transition to respective upper side edges 126 and 128 which are of limited vertical extent and are spaced apart a widthwise distance essentially restricting any lateral slidable movement of door 110. Thus, to remove or insert door 110, the cleaning personnel need only lift it the short distance represented by the lengthwise extents of edges 126 and 128, and slide it laterally in or out of the tracks 118 and 120. As before, no excessive physical effort is required for this procedure.
FIGS. 1 and 11 also reveal the presence of a downwardly depending position locator component 130 which is attached to the door 110. This device extends downwardly such that its tip is positioned at a gap 132 within the lower support assembly 12 above an access door 136. Component 130 functions to close or otherwise actuate a proximity switch by its adjacency with switch component 133 (FIG. 11) located just behind gap 132. Door 136 is seen to be hinged at 138 and is latched at latches 140. Note the presence of a lower gap 142 beneath door 136. The proximity switch arrangement assures that high pressure nozzles within chamber 22 cannot be activated until door 112 is in a fully enclosing orientation. In similar fashion, a position locator component 142 is fixed to the lower region of front door 56. As seen in FIG. 5, locator component 142 cooperates with a proximity switch 144 which extends rearwardly from a circuit enclosure 146 attached, in turn, to the bottom of deck cover 34. Deck cover 34 is shown in FIG. 5 in an open, vertical orientation, being contained therein by a conventional elbow latching mechanism 148. With the arrangement shown, when the deck 34 is closed, the proximity switch 144 is adjacent the locator component 142 and assumes a closed or circuit completing orientation. Thus, the front door 56, side door 112, as well as deck cover 34 must be closed in order for the apparatus 10 to be enabled for operation. FIG. 5 also reveals the presence of a start/stop switch 150 associated with the circuit enclosure 146 as well as a pressure gauge 152 which may be viewed through an opening 154 within deck cover 34 as seen in FIG. 1.
Looking to FIGS. 2, 4, and 5, the water input components associated with apparatus 10 are revealed. In this regard, apparatus 10 utilizes two plant water inputs, one from the cold water supply, and the other from the plant hot water supply. This parallel input serves to make more efficient utilization of the typically limited water supplies of a processing plant and advantageously permits the utilization of heated water while permitting chlorine addition at the unheated water input. With the arrangement, water may be ejected from the cleaning nozzles at an optimum temperature of about 100° F. which substantially improves flesh removal. Additionally, the acidic nature of the chlorinated cleaning fluid functions to enhance bacteria removal as well as flesh contaminants. FIG. 4 reveals the dual water input. In this regard, heated water is introduced at inlet 160 to a filter 162, the output of which is directed to the interior of apparatus 10. Unheated water is introduced at inlet 164 of filter 166. The output of filter 166 at conduit 168 is introduced to a chlorinator 170. Chlorinator 170 may be provided as a metering pump, for example a series 410-1 metering pump marketed by TAT Engineering Corporation of Branford, Conn. The output of chlorinator 170 is directed to the interior of apparatus 110 via conduit 172. FIG. 6 additionally shows a waste fluid output port 178 which functions to convey contaminant containing fluids from the chamber 22.
Looking to FIG. 6, the internal components of apparatus 10 are revealed. In the figure, the lower support assembly 12 is seen to include a lower support platform area represented in general at 182 and, preferably, structured robustly. In this regard, it may be formed, for example, of four C-channel members. The platform area 182 supports a motor 184 which may be, for example, of a 10 horsepower variety. The output of motor 184 at drive pulley 186 is transmitted to a pump pulley assembly 188 via belt arrangement 190. Pulley assembly 188 functions to drivably rotate pump shaft 192 of a stainless steel pump 194. Pump 194 is configured having two parallel inlets as well as two parallel outlets as described later herein in conjunction with FIG. 17. Pulley assembly 188 additionally drives a gear reduction assembly 204 through belt 206 and pulley 208. Assembly 204 functions to rotatably drive a main sprocket drive shaft 210. Drive also is imparted to a gear assembly 212 through pulley 214 and belt 216. Belt 216, in turn, is driven by a pulley (not shown) attached to pump shaft 192. Gear assembly 212 serves to rotate a head drive shaft 218 which extends to the upper portion 24 of chamber 22. Positioned at the top of lower support assembly 12 is a stainless steel fluid discharge ramp 220 which includes an upwardly disposed stainless steel fluid transfer surface 222. Note that the transfer surface 222 is canted or sloped at an angle of about 5° and extends continuously from a location beneath access deck assembly 32 to the outlet port 178. The slope of the ramp facilitates the removal of contaminant carrying fluids serving both to avoid cross-contamination of cleaner gloves with respect to contaminated gloves, and to minimize bacteria build-up due to the lowered dwell time of contaminated materials within the apparatus 10. Connections of components to the ramp 220 at surface 222 are, where appropriate, by sanitary welds to avoid the presence of pockets where bacteria may build-up. Additionally, the bearing blocks supporting drive shafts 210 and 218 are designed to avoid bacterial build-up and to assure that there is no egress of chlorine containing contaminated fluids into lower support assembly 12.
Further supporting the aspect of avoidance of bacterial build-up, drive shaft 210 is seen to extend through an opening in discharge ramp 220. Shaft 210 is fixed, for example, by welding to the main sprocket 232 of conveyor assembly 40. Thus a two-piece composite structure is avoided. Shaft 210 is supported at ramp surface 222 by a bearing block 230 which is described in detail later herein. In general, conveyor assembly 40 includes an access or secondary stainless steel sprocket 234 and chain guiding stainless steel idler pulleys 236 and 238, one of which is shown in the instant figure and both of which are seen in FIG. 12. A tension adjustment assembly represented generally at 240 serves to adjust tension on the chain component of conveyor assembly 40 through sprocket 234. Assembly 240 is connected to a bracket which is welded to surface 222 of discharge ramp 220 in a manner facilitating fluid flow down the above-discussed slope thereof. In general, the main sprocket 232 provides drive to the conveyor assembly 40 to maneuver glove mounts 42 and associated gloves 44 into the containment chamber 22 about a generally circular conveyor locus. The glove mounts 42 are fed into this locus through the earlier-described entrance curtain assembly 66 and exit therefrom through the exit curtain assembly 68 (FIG. 3). Main sprocket 232 rotates about a main sprocket axis 242.
Positioned above the main sprocket 232 and glove mounts 42 as they are moved about the chamber locus of movement is a rotating spray head assembly represented generally at 250. Rotation is developed for assembly 250 from belt 216 and pulley 214 functioning to drive stainless steel head drive shaft 218 from gear assembly 212. Shaft 218 extends through a bearing block 252 mounted upon the fluid transfer surface 222 of ramp 220 in a manner similar to the mounting provided at beating block 230. Shaft 218 extends upwardly to be supported at a pillow block 254 and above which is drivably coupled two a pulley 256. Looking additionally to FIG. 7, it may be observed that pulley 256 is coupled in driving relationship with a belt 258 which, in turn, is coupled in driven relationship with a pulley 260. Pulley 260, in turn, drives the head manifold assembly 262 through a shaft seen in FIG. 8 at 264. The latter figure reveals that the head manifold assembly 262 performs in four quadrants, each having a principal stainless steel conduit 266-269. Coupled to each of the four principal quadrants are three stainless steel nozzles, such as nozzles 272-274 as seen in conjunction with principal conduit 267 in FIGS. 7 and 8. High pressure cleaning fluid as earlier described to be water at about 1,000 psi which is chlorinated and at a temperature of about 100° F., is expressed from these nozzles onto the gloves 44 in somewhat of a cascading fashion. In this regard, the nozzles within the quadrants are pointed at progressively lower and lower regions of the gloves 44 such that a form of downwardly sweeping cleaning action is developed. In this regard, note in FIG. 7 that nozzle 272 is at a lowest elevation, while nozzles 273 and 274 function to express highly pressurized cleaning fluid respectively below and at the fingertips of gloves 44. The figure further shows that such nozzles as at 276 and 277 are oriented and dimensioned to express fluid under pressure at progressively higher levels upon gloves 44. In general, the fingertips of gloves 44 will contain a larger amount of flesh or flesh contaminant. Thus, an enhanced form of cleaning action is employed. Looking particularly to FIG. 6, it may be observed that shaft 264 of the spray head assembly 250 rotates about a spray head axis 284. This rotation is in the opposite rotational sense as the conveyor locus rotation provided from main sprocket 232. However, the spray head assembly 250 is rotated about axis 284 at a greater rate of speed, e.g. 50 rpm. FIG. 6 reveals that the sprocket axis 242 is offset from spray head axis 284 by a small but optimal amount of about 0.25 inch. This 0.25 inch offset is provided to develop an undulating horizontal relative movement of the spray nozzles directed at the tip of gloves 44, for example, as provided at nozzles 273 and 274 described in connection with FIGS. 7 and 8. The undulating relative movement during the movement of the glove tip cleaning spray head nozzles improves cleaning action at the infested tips. To achieve adequate performance of the drive system for head assembly 250, it is desirable that pulleys 256 and 260 be formed of a temperature stable material able to withstand the 100° cleaning fluid temperature and which material also is required to be chemically stable in view of the chlorinated fluids utilized. It has been found that a polymer sold under the trade designation "Delrin" by E. I. DuPont de Nemours is suitable for this purpose. Belt 258 also encounters this severe environment. Preferably, the belt 258 is provided as a "Polycord" belt marketed by Habisit Belting, Inc., having a place of business at Schaumburg, Ill. Fluid transfer connection to the assembly 250 is from one of the two outlets of pump 194 and by flexible conduit to connection with the fluid pressure input to the stainless steel swivel assembly 286 of head assembly 250. Access to the upward portion of assembly 250 is through a bolted cover 288 located at the top surface of chamber 22.
In view of the nozzle positioning and undulating relative movement thereof during rotation, it is desirable that the glove mounts 42 remain vertically stable so as to consistently position gloves 44 for nozzle cleaning action. As part of this stability, an inner guide ring 290 is provided within chamber 22 against which the inward facing sides of mounts 42 may slidably abut during their travel along the chamber locus. Ring 290, in turn, is coupled in cantilever fashion with an upstanding stainless steel splash guard assembly represented generally at 292 by an attachment arrangement represented at 294, as is revealed in FIGS. 8 and 9. FIG. 7 particularly reveals that the ring 290 is canted from horizontal. This arrangement is provided to assure that the gloves 44 which it may contact are not shielded by it from cleaning activity. In this regard, should ring 290 be horizontal, an opportunity for such shielding is presented.
Glove mounts 42 are provided with an outwardly disposed guide 296 at a lower elevation within chamber 22. Guide 296 is revealed in FIGS. 6, 8, and 9 as being formed of a polymeric sheet which is bolted to inwardly depending stainless steel brackets, two of which are shown at 298 and 300 in FIG. 6. FIGS. 8 and 9 show that the guide 296 is formed having a curved inner aperture, the periphery of which is shown at 302, against which the lower portions of glove mounts 42 slidably abut during the course of their movement along the chamber locus of movement.
Referring to FIGS. 9 and 10, conveyor assembly 40 and the locus of movement thereof is revealed in enhanced detail. In this regard, the assembly 40 is seen to be formed of a continuous stainless steel chain 310 which is positioned in driven relationship about main sprocket 232, and which extends through entrance opening 66 and exit opening 68 to be wound about secondary sprocket 234 seen in FIG. 10. To align chain 310 for movement through curtain assemblies 66 and 68, the earlier noted idler sprockets as are revealed in FIG. 12 at 236 and 238 are provided. These sprockets 236 and 238 respectively are mounted for free rotation upon stainless steel shafts seen in FIG. 12 at 312 and 314. As seen in FIG. 13, shafts 312 and 314, in rum, are mounted upon a stainless steel bracket or fixture 316 welded to fluid transfer surface 222 of ramp 220. Secondary sprocket 234 is mounted upon and supported by a stainless steel shaft 318 forming part of the tension adjustment assembly 238. Adjustment of tension is provided, as shown in FIG. 10, by the bias asserted against shaft 318 from stainless steel spring 320 in conjunction with the compression asserted thereto from a stainless steel bolt or machine screw 322. Note in FIG. 10 that shaft 318 extends upwardly from secondary sprocket 234 to rotate within and support an entrance guide 324 against which the inwardly disposed surfaces of lower mount components 48 abuttably slide. Guide 324 contributes to a necessary isolation of contaminated gloves entering chamber 22 through entrance curtain assembly 66 from the clean gloves emerging from chamber 22 through exit curtain assembly 68. The spacing developing this isolation should be at least about five inches.
With the arrangement shown, looking to FIG. 9, the conveyor locus of movement as established by chain 310 has an entrance region in conjunction with its movement along from sprocket 234 entrance guide 324, whereupon it extends into chamber 22 to establish a chamber region wherein contaminated gloves entering through entrance curtain assembly 66 are progressively cleaned of flesh and bacteria, whereupon the locus of movement extends through the chamber forward portion and exit curtain assembly 68 to sprocket 234. Within the latter region, personnel may remove the glove supporting fork-shaped glove supports 50 from the components 48 for removal of cleaned gloves 44. In general, the main sprocket is provided having about an 18 inch diameter and is driven at a rate of about 11/2 rpm. Correspondingly, the nozzles at the spray head assembly 250 are rotated in the same direction at about 50 rpm. The cleaning or dwell time for the gloves while traveling along the chamber region of the locus of movement is about 62 seconds. The latter interval provides about a 99% reduction in bacteria plate count and is rapid enough to permit the cleaning of gloves during normal shift breaks.
FIGS. 8-10 and 12 additionally reveal detail of the splash guard assembly 292. Assembly 292 not only protects personnel standing adjacent access deck assembly 32 from high pressure spray at 100° F. in supplement with the curtain assemblies 66 and 68, but also assures an avoidance of cross contamination of gloves 44 at the entrance region of their locus of movement from clean gloves moving to the exit region. The assembly 292 is generally triangular in cross section and, as seen in FIG. 10, extends upwardly to a tip 326 located adjacent the tips 52 of gloves 44 as they move within chamber 22. This height is selected as an amount effective to block fluid sprayed over and splashing from gloves in the vicinity of the conveyor locus entrance region from contacting and cross contaminating gloves which are "clean" and exiting from the chamber 22. The assembly 292 is hollow in the region beneath guide ring 290 so as to provide a conduit 328 serving to guide fluids downwardly and then outwardly from a port 330 onto fluid transfer surface 222. Assembly 292 is bolted to bracket 317 which is welded to bracket 316 and surface 222, which, as noted above, is welded to fluid transfer surface 222 of ramp 220. FIGS. 10 and 12 further reveal the provision of a separation plate 332 which functions to assure the noted isolation of the entrance region from the exit region and, as seen in FIG. 6, the plate 332 further supports the stainless steel vertical mount for curtain 78 including stainless steel strap 84. With the arrangement shown, as cleaning shift personnel lift the door 56, polymeric sheets 78, 82, 90, and 92, being fixed to separation plate 332 by strap 84 remain in place for support during cleaning procedures.
Referring to FIGS. 14A and 14B, the structure of the glove mounts represented generally at 42 as they are mounted upon chain 310 is revealed in enhanced detail. Because of the substantial height of the glove mount and necessity to avoid cross contamination of exit region containing clean gloves with respect to gloves entering chamber 22, the attachment of the mounts 42 to chain 310 must be structurally reliable. In FIG. 14A, a portion of chain 310 is reproduced with the same numeration. This chain 310 incorporates a master link 340 which as seen additionally in conjunction with FIG. 14B functions to support an L-shaped lower mount component 342. In this regard, the pins 344 and 346 utilized with master link 340 extend through and secure a horizontal flange 348 of mount component 342. Component 342 additionally includes an attachment flange 349 which will be aligned with the link 340 along the conveyor locus and which functions to vertically support rod support component 48. Attachment of the component 48 to flange 349 is by a stainless steel bolt arrangement including two bolts 351 and 352. Two bolts 351 and 352 are employed to assure the verticality of rod support component 48. It may be recalled that the glove mounts 42 are relatively high, exhibiting correspondingly heavy turning or pivoting moments at their connection with chain 310. FIG. 14B additionally reveals the presence of a vertical, cylindrical support cavity 358 which terminates at 360 and communicates with a fluid relief passage 362. Passage 362 facilitates the cleaning of cavity 358 as well as providing a drain for any fluids which may collect therein. The upwardly disposed portion of rod support component 48 is provided with a vertical alignment slot 364 which receives an alignment pin 366 fixed to and extending from the lower disposed rod 368 of fork-shaped glove support 50.
The cleaning of equipment and floors of a meat processing facility is a physically taxing duty typically undertaken during late evening or early morning shifts. Accordingly, it is important that the equipment subject to cleaning such as apparatus 10 be constructed to avoid pockets leading to bacterial build-up and that such equipment be easily dismounted for purposes of cleaning. As indicated earlier herein, the front and side doors 56 and 112 of apparatus 10 readily are removed with a vertical lifting requirement of minimal extent. This exposes the entire chamber 22. As illustrated in connection with FIG. 5, the deck cover 34 of access deck assembly 32 is simply pivoted upwardly to provide access therebeneath. Next, as revealed in conjunction with FIG. 6, this procedure opens the entire fluid transfer surface 222 to easy access by cleaning personnel. In addition to being canted to promote contaminant containing fluid removal, the surface 222 supports only the minimal necessary components employed with apparatus 10. In this regard, FIG. 11 reveals that door 112 is supported above surface 222 by flange 380 such that the bottom of the door is not located within a collection, albeit temporal, of contaminant containing fluid. In similar fashion, door 56 is supported above surface 222, for example by a flange or protrudance 382 seen in FIG. 6. Bearning blocks 230 and 252, respectively supporting shafts 210 and 218 also are structured for the purpose of assuring that no chlorine containing fluids as well as contaminants may migrate into lower support assembly 12 and to minimize any opportunity for bacteria build-up. Looking to FIG. 15, bearing block 252 is revealed at an enhanced level of detail. Block 252 includes a polymeric housing 384 which is formed of a material having appropriate strength and which, additionally, is immune to the corrosive effects of chlorinated cleaning fluids and temperatures employed within chamber 22. A material suited for this purpose is marketed under the trade designation "Delrin" by E. I. DuPont de Nemours. The central portion of block 384 is bored at 386 and the block is centered over a circular opening 388 in deck assembly 220. To assure that no fluids may migrate into the opening 388, a circular groove of semi-circular cross-section is formed within the lower surface 390 of block 384 which receives polymeric O-ring 392. The entire assembly is retained in position by four bolts, two of which are seen at 394 and 396. O-rings 392 are positioned outwardly as far as practical from the opening 386 for the purpose of minimizing the extent of any region of possible bacterial capture.
A brass bushing 402 is positioned within opening 386 for receiving and rotatably supporting stainless steel shaft 218. Finally, polymeric seal 404 is located within the upper portion of opening 386 and is secured to the shaft 218 by stainless steel ting 406.
Referring to FIG. 16, the corresponding mounting of beating block 230 upon ramp 220 is shown. Block 230 includes a polymeric housing 408 formed of the same material as housing 384. Housing 408 is configured having a centrally disposed bore 410 which is oriented over a circular opening 412 within ramp 220. The lower surface 414 of housing 408 is configured having a recess of semi-circular cross section functioning to receive a polymeric O-ring 416. Housing 408 and O-ring 416 are secured in position by four bolts, two of which are shown at 418 and 420. Rotatably supporting the drive shaft 210 is a brass bushing 426. Thus configured, the beating block 230 is immune to the corrosive effects of the environment of chamber 22 and, with the mounting thereof incorporating O-ring 416, the regions susceptible to bacteria build-up are minimized.
Referring to FIG. 17, a schematic representation of the drive, control, and fluid delivery components of apparatus 10 is revealed. Where appropriate, the same numeration employed in earlier figures is utilized in the schematic diagram but in primed fashion. In the figure, hot water is seen introduced at port 160' whereupon it is filtered at filter 162' and directed via conduit 440 through a heat adjustment valve 442 to one input of pump 194'. The stainless steel pump 194' is of a two input, two output variety. The pump may be provided, for example, as a Model 1050 pump marketed by cat Pumps U.S.A., Inc. of Minneapolis, Minn. One output of pump 194' is coupled as represented by conduit 444 with a pressure damper or accumulator 446. While such devices typically are not employed with the pumping arrangement shown, it has been found that the utilization of such an accumulator or damper 446 improves the performance of pump 194'. Additionally, communicating with conduit 444 is a pressure valve or blow-off valve 448.
The cold water input to the apparatus is represented at 164' which is directed to the input of filter 166'. Filtered cold water is directed, as represented at conduit 168', to a chlorinator 170'. Preferably, chlorinator 170' adds chlorine with a positive pressure addition to an extent that the resultant cleaning fluid, following hot and cold water mixture at pump 194', will exhibit a chlorine content of between about 150 and 200 parts per million (ppm). Within this range, a chlorine content of 180 ppm is preferred. Fluid having been chlorinated, then is passed via conduit 172' to an opposite input to pump 194'. A pressure switch 450 is provided in fluid communication with hot water conduit 164' and has a normally closed orientation. Upon the occurrence of an excessive pressure at conduit 164', switch 450 will open.
Pump 194' is driven from motor 184' as represented by dashed association line 452. The opposite output of pump 194' is represented at conduit 454 which is directed to a swivel connector 286' associated with head assembly 250'. Pressure gauge 152' is seen coupled with conduit 454.
With the arrangement shown, the cleaning fluid directed to head 250' is at an optimum temperature value of about 100° F. Additionally, the fluid will be chlorinated to an optimum value of 180 ppm, and the fluid is expressed from the head assembly 250' at about 1000 psi. This combination has been found to optimally reduce glove plate counts as well as drive flesh contaminants from the gloves. An additional advantage accrues from the utilization of both hot and cold water for the system inasmuch as the supplies of water available in typical processing plants are limited because of the high demands of the overall processes involved. By utilizing both the hot and cold water supplies of the plant in parallel, assurance is made that adequate water volume or flow is available for the pump 194' of apparatus 10. No pump starvation is encountered. Additionally, the positive pressure input from chlorinator 170' promotes improved pressures.
Motor 184' generally will have a rating of about 10 hp. The motor is coupled to three phase high voltage inputs as represented at lines 460-462. Lines 460-462 are seen directed to a motor relay 464 which carries out start and stop functions. From relay 464, a three phase input is provided to motor 184' from lines 466-468. Phase line 460 and neutral line 461 are tapped by respective lines 470 and 472 and the voltages associated therewith are reduced at a step-down transformer 474. The lower control voltage levels are provided from transformer 474 at lines 476 and 478. Line 478 extends through a normally open start switch 150' which, when momentarily closed, serves to close a motor relay control 480. When actuated, motor relay control 480 effects the closure of motor relay 464 as represented by dashed lines 482 and 484. Line 478 as well as associated line 476 may be open circuited by a stop switch 150' which is incorporated mechanically with the start function thereof as well as by pressure switch 450 and proximity switches 486 and 488. Switch 486 may, for example, carry out the function of position locator component 130 as it is associated with proximity device 133 (FIG. 11), while switch 488 represents the function carried out in conjunction with proximity device 144 as associated with position locator component 142 (FIG. 5).
Since certain changes may be made in the above-described system and apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the description thereof or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | Apparatus is provided for cleaning industrial apparel such as wire mesh safety gloves used in processing meats such as chickens. The apparatus employs a containment chamber within which a conveyor carries the gloves which are mounted upon substantially elevated glove mounts. Within the chamber, high pressure nozzles are rotated to express hot chlorinated water upon the gloves over a residence interval of about one minute. The apparatus employs parallel inputs of hot and cold water, the latter being chlorinated within a range of about 150 to 200 ppm. Cleanability is enhanced through the utilization of facilely removed light weight flat front and side doors and a pivoting forward deck assembly. Bacteria-promoting pockets and the like are minimized through the utilization of sanitary welds and O-ring mounted polymeric bearing blocks. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
FEDERAL SPONSORSHIP
Not Applicable
JOINT RESEARCH AGREEMENT
Not Applicable
TECHNICAL FIELD
This invention pertains generally to highway road signs. More particularly, the invention pertains to a highway road sign capable of opening and folding to display or conceal information presented on a face of the road sign. The folding of the roadway sign in accordance with the invention is further capable of opening and closing remotely. Power to the folding roadway sign may be provided with a solar energy. The foldable sign of the invention is also operable when subjected to cross winds.
BACKGROUND
Generally, traditional road signs have been built of a thicker gauge sheet metal in order to withstand extreme weather conditions. During roadway construction, a need still exists for sturdy roadway signs, however, separate specialized road signs have been utilized in order to convey temporary messages when crews are working in a work zone. When the work zones are inactive it may be preferred to block from visibility the message conveyed on the sign. Some localities or agencies may even mandate removal or blockage of work zone signage when crews are not present in the work zone. Additional sheet metal or covers may be added to the sign to block the messages when crews leave the work area. Alternatively, the specialized signs may be built in halves that are able to fold or flip. These folding signs may be used to block the message conveyed on the sign. Prior signs have required manual manipulation of the sign to alter the characteristics, position, or condition of the sign.
It is desirable to provide a folding sign that is rigid and sturdy and that does not have a wide gap between the halves when the sign is opened (making the message on the sign disjoint). Further, it is desirable to secure the two halves of the sign together in a way capable of withstanding significant winds when in the open or folded positions. Also, at times, it may be preferred to be able to remotely activate the opening and closing of the sign. For example, the sign may be positioned in a work zone area, at a location, making the conditions less than ideal to manually fold and secure the sign. And, during inclement weather, the manual folding of signs may be less than desirable.
SUMMARY
Embodiments according to aspects of the invention are rigid and sturdy and capable of automatically folding or flipping the two halves of a roadway sign between an open and closed position. According to other aspects, the apparatus of the invention to fold and open the roadway sign is capable of being activated remotely to either open or close the sign. Further, the activation of multiple roadway signs to open or close may be daisy chained together electronically such that an activation of one sign to an open or closed position results in subsequent activation of multiple corresponding signs. The invention may also utilize solar power to provide energy for the activation of the roadway sign between the open and closed position.
These and other embodiments according to aspects of the invention include an apparatus for folding a highway safety sign, wherein the apparatus includes at least one hinge, braces, mounts, a support member, and an actuator. The hinge includes two hinge mounts wherein each hinge mount is attached to a half of a roadway sign. A first brace is fixed to the first half of the sign and is further engaged to the first hinge mount of the hinge. Similarly, a second brace is fixed to the second half of the sign and is engaged to the second hinge mount of the hinge. The support member articulates at a mid-joint and has a first end pivotally attached to the first brace and a second end pivotally attached to the second brace. The actuator has a first end pivotally coupled to the hinge and has a second end pivotally coupled to the articulating support member.
The hinge portion of the apparatus of the invention may further have a first set of arms having first ends pivotally attached to the first hinge mount and having second ends slidingly engaged to the second hinge mount. Similarly, the hinge may have a second set of arms having first ends pivotally attached to the second hinge mount and having second ends slidingly engaged to the first hinge mount. Additionally, the hinge may include a pivot pin connecting mid portions of the first and second set of arms of the hinge. Also, a first end of the actuator may be pivotally coupled to at least one of the first and second set of arms of the hinge. According to aspects of the invention, an embodiment of the invention may further include first and second spaced apart outer hinges that are capable of coupling to the sign and wherein the hinge is positioned between the first and second spaced apart outer hinges. The actuator may be electrically coupled to a wireless power switching control that allows a user to send a signal to the switching control to activate the sign to an open or closed position. Further, a solar panel may supply energy to the switching control and the actuator.
Another embodiment according to aspects of the invention includes a sign having first and second separable halves, at least three floating hinges fixed or attached to the sign, braces attached to the sign and one of the floating hinges, an articulating support member, and an actuator. Each hinge may include a first hinge mount fixed to the first half of sign, a second hinge mount fixed to the second half of sign, a first set of arms having first ends pivotally attached to the first hinge mount and having second ends that slide in guideways of the second hinge mount, a second set of arms having first ends pivotally attached to the second hinge mount and having second ends that slide in guideways of the first hinge mount, and a pivot pin that connects mid portions of the first and second set of arms. A first brace is fixed to the first half of the sign and engaged to the first hinge mount of the third floating hinge and a second brace is fixed to the second half of the sign and engaged to the second hinge mount of the third floating hinge. The articulating support member has a first end pivotally attached to the first brace and a second end pivotally attached to the second brace. The actuator has a first end pivotally coupled to at least one of the first and second set of arms of the third floating hinge and has a second end pivotally coupled to a joint of the articulating support member.
According to aspects of the invention the actuator may be electrically coupled to a wireless power switching control. Additionally, a solar panel may be provided and electrically coupled to the actuator and switching control to supply energy to the actuator and switching control. In an embodiment of the invention the actuator may be of the linear actuation type and may be of a solenoid or hydraulic type of known suitable construction.
The accompanying drawings, which are incorporated in and constitute a portion of this specification, illustrate embodiments of the invention and, together with the detailed description, serve to further explain the invention. The embodiments illustrated herein are presently preferred; however, it should be understood, that the invention is not limited to the precise arrangements and instrumentalities shown. For a fuller understanding of the nature and advantages of the invention, reference should be made to the detailed description in conjunction with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
In the various figures, which are not necessarily drawn to scale, like numerals throughout the figures identify substantially similar components.
FIG. 1 is a back left perspective view of a remote staked highway road sign apparatus of the present invention shown in an open position;
FIG. 2 is a back right perspective view of a remote staked highway road sign apparatus of the type shown in FIG. 1 ;
FIG. 3 is a back left perspective view of a remote staked highway road sign apparatus of the present invention shown in a partially closed position;
FIG. 4 is a back left perspective view of a remote staked highway road sign apparatus of the present invention shown in a closed position;
FIG. 5 is a back right perspective view of an embodiment of a highway road sign apparatus of the present invention shown in an open position;
FIG. 6 is a back left perspective view of an embodiment of a highway road sign apparatus of the present invention shown in an open position;
FIG. 7 is a back left perspective view of an embodiment of a highway road sign apparatus of the present invention shown in a partially open position;
FIG. 8 is a back right perspective view of an embodiment of a highway road sign apparatus of the present invention shown in a partially open position;
FIG. 9 is a front perspective view of an embodiment of a highway road sign apparatus of the present invention shown in a closed open position;
FIG. 10 is a back perspective view of an embodiment of a highway road sign apparatus of the present invention shown in a closed position;
FIG. 11 is a back perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in an open position;
FIG. 12 is a front perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in an open position;
FIG. 13 is a back left perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in a partially open position;
FIG. 14 is a back right perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in a partially open position;
FIG. 15 is a front upper perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in a closed position;
FIG. 16 is a front lower perspective view of an embodiment of a middle hinge, braces, support member, and actuator of a highway road sign of the present invention shown in a closed position;
FIG. 17 is a front lower perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in an open position;
FIG. 18 is a back perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in an open position;
FIG. 19 is a back perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially closed position and having a pin removed;
FIG. 20 is a back left perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially closed position and having a pin removed;
FIG. 21 is a back perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially closed position;
FIG. 22 is a top perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially closed position;
FIG. 23 is a back perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially open position;
FIG. 24 is a back perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a partially open position;
FIG. 25 is a front left perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a closed position;
FIG. 26 is a bottom perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a closed position;
FIG. 27 is a top perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a closed position; and
FIG. 28 is a top side perspective view of an embodiment of a hinge of a highway road sign of the present invention shown in a closed position.
DETAILED DESCRIPTION
The following description provides detail of various embodiments of the invention, one or more examples of which are set forth below. Each of these embodiments are provided by way of explanation of the invention, and not intended to be a limitation of the invention. Further, those skilled in the art will appreciate that various modifications and variations may be made in the present invention without departing from the scope or spirit of the invention. By way of example, those skilled in the art will recognize that features illustrated or described as part of one embodiment, may be used in another embodiment to yield a still further embodiment. Thus, it is intended that the present invention also cover such modifications and variations that come within the scope of the appended claims and their equivalents.
The apparatus 10 of the present invention is particularly well suited for remote opening and closing the first and second halves 16 and 18 of a two piece work zone roadway sign 14 . With reference to the Figures, various embodiments according to aspects of the invention will be described in greater detail. With reference to FIGS. 1-5 , a work zone roadway sign assembly is shown removed and suspended above the ground. The sign 14 includes a first half 16 and second half 18 coupled together by first hinge 30 , second hinge 60 and third hinge 190 . The apparatus for folding the sign 14 generally includes at least one hinge 60 , bracing 110 , an articulating support member 130 , and an actuator 160 . Additional hinges 30 and 190 may be aligned on either side of hinge 60 and each hinge includes two hinge mounts wherein each hinge mount is attached to a corresponding first and second half 16 and 18 of the roadway sign 14 . The sign 14 may be mounted to stakes 176 and 178 that are buried or driven into the ground. The apparatus 10 may further include a remote controlled power switch control 180 and solar panel 188 of known suitable construction coupled to the actuator 160 with electrical conduits 184 . The solar panel is attached to stake 176 and the remote wifi control 180 is coupled to the lower half 18 of the sign 14 . The wireless power switch control or remote wifi 180 may further include an antenna 182 . Without limitation intended, the wireless control may include wi-fi, z-wave or Bluetooth systems having hand held, key fob or switch controllers. Operating system apps may also be utilized to create additional functionality for the controller.
Referring to FIGS. 6-10 , bracing 110 includes a first brace 112 fixed to the first half 16 of the sign 14 and is further engaged to a first hinge mount 62 of the second hinge 60 . Similarly, bracing 110 includes a second brace 114 fixed to the second half 18 of the sign 14 and the second brace 114 is further engaged to the second hinge mount 64 of the second hinge 60 . Articulating support member 130 couples together the first brace 112 and second brace 114 . The support member 130 articulates at a mid-joint 132 and has a first end 134 pivotally attached to the first brace 112 and a second end 136 pivotally attached to the second brace 114 . The actuator 160 has a first end 162 pivotally coupled to the hinge 60 and has a second extendable end 164 pivotally coupled to the articulating support member 130 .
Those skilled in the art will appreciate that the actuator 160 may be of an integrated electric actuator of known suitable construction that combines servomotor, digital drive, linear controller and actuator in a compact unit, such as those available from Motion Control Products and Tolmatic. In use, when the second end 164 extends out of the main body, the two halves of the sign pivot closed and then the second end 164 draws into the main body the two halves of the sign pivot open.
FIGS. 11-16 also illustrates the attachment, coupling and actuation of the hinge 60 , bracing 110 , articulating support member 130 and actuator 160 . The first ends 134 of support member are pivotally attached with pivot pins 118 to the first braces 112 and the second ends 136 of support member 130 are pivotally attached with pivot pins 118 to the second brace 114 . A pivot pin 118 couples the first and second ends 134 and 136 of the support members to an end of the second extendable end 164 of the actuator 160 at a mid-joint 132 . Sign mounting pads 116 couple free ends of each brace member to each corresponding half of the sign. A flange of the each brace member 112 and 114 extends over the top of corresponding hinge mounts 62 and 64 to provide additional stability and continuity between the sign halves 16 and 18 , the braces 112 and 114 and the articulating support member 130 . Further, the pads 116 and flanges 120 increase rigidity and reduce the potential of the sign twisting when subjected to cross winds. The reliefs or cutouts 122 in the bracing 112 and 114 further reduce resistance to a cross wind. The pivot attachment of the first end 134 and second end 136 may be modified to couple directly to the respective hinge mounts, however, coupling to the bracing is affective. The hinge 60 includes features that allow the edge of the two signs to align adjacent and with minimal gap when the sign is in the open position and allows a gap 124 between the signs when in the closed folded position (see, for example, FIG. 15 ).
FIGS. 17-28 illustrates various embodiments of the hinges 30 , 60 and 190 in accordance with aspects of the invention. FIGS. 17 and 18 illustrate hinge 30 in the open position. FIGS. 19 through 24 illustrate hinges 30 , 60 and 190 in a partially open position and FIGS. 25 through 28 illustrate hinge 190 in the closed position. Hinge 30 includes first hinge mount 32 , second hinge mount 34 , a top pair of arms 36 and a bottom pair of arms 38 . A first end of the top pair of arms 36 is pivotally coupled to the second hinge mount 34 with a bottom pivot pin 44 . A second end of the top pair of arms 36 is slidingly coupled to the first hinge mount 32 with a guideway pin 52 that slides in guideways 52 formed in the hinge mount 32 . Similarly, a first end of the bottom pair of arms 38 is pivotally coupled to the first hinge mount 32 with a top pivot pin 40 . A second end of the bottom pair of arms 38 is slidingly coupled to the second hinge mount 34 with a guideway pin 54 that slides in guideways 48 formed in the hinge mount 34 . The pairs of arms 36 and 38 are pivotally coupled together with a middle pivot pin 42 . A relief 50 may be formed in the first and second hinge mounts 32 and 34 to allow the hinge mounts to pivot into an open position without the arms binding on the hinge mounts. Holes 56 are formed in the hinge mounts to allow the hinge mounts to be attached to a sign.
Middle hinge 60 includes first hinge mount 62 , second hinge mount 64 , a top pair of arms 66 and a bottom pair of arms 68 . A first end of the top pair of arms 66 is pivotally coupled to the second hinge mount 64 with a bottom pivot pin 74 . A second end of the top pair of arms 66 is slidingly coupled to the first hinge mount 62 with a guideway pin 88 that slides in guideways 72 formed in the hinge mount 62 . Similarly, a first end of the bottom pair of arms 68 is pivotally coupled to the first hinge mount 62 with a top pivot pin 70 . A second end of the bottom pair of arms 68 is slidingly coupled to the second hinge mount 64 with a guideway pin 90 that slides in guideways 78 formed in the hinge mount 64 . The pairs of arms 66 and 68 are pivotally coupled together with a middle pivot pin 72 . A relief 80 may be formed in the first and second hinge mounts 62 and 64 to allow the hinge mounts to pivot into an open position without the arms binding on the hinge mounts. Holes 86 are formed in the hinge mounts to allow the hinge mounts to be attached to a sign. The actuator pivot pin mount 82 extends form the top arms 66 . Those skilled in the art will appreciate that the actuator mounts 82 may be formed and extend from either the top arms 66 , bottom arms 68 , or a combination of both. Pivot pin 84 couples the actuator mount to the first end 162 of actuator 160 (see, for example, FIG. 11 ).
Opposing hinge 190 includes first hinge mount 192 , second hinge mount 194 , a top pair of arms 196 and a bottom pair of arms 198 . A first end of the top pair of arms 196 is pivotally coupled to the second hinge mount 194 with a bottom pivot pin 204 . A second end of the top pair of arms 196 is slidingly coupled to the first hinge mount 192 with a guideway pin 212 that slides in guideways 206 formed in the hinge mount 192 . Similarly, a first end of the bottom pair of arms 198 is pivotally coupled to the first hinge mount 192 with a top pivot pin 200 . A second end of the bottom pair of arms 198 is slidingly coupled to the second hinge mount 194 with a guideway pin 214 that slides in guideways 208 formed in the hinge mount 194 . The pairs of arms 196 and 198 are pivotally coupled together with a middle pivot pin 202 . A relief 210 may be formed in the first and second hinge mounts 192 and 194 to allow the hinge mounts to pivot into an open position without the arms binding on the hinge mounts. Holes 216 are formed in the hinge mounts to allow the hinge mounts to be attached to a sign.
These and various other aspects and features of the invention are described with the intent to be illustrative, and not restrictive. This invention has been described herein with detail in order to comply with the patent statutes and to provide those skilled in the art with information needed to apply the novel principles and to construct and use such specialized components as are required. It is to be understood, however, that the invention can be carried out by specifically different constructions, and that various modifications, both as to the construction and operating procedures, can be accomplished without departing from the scope of the invention. Further, in the appended claims, the transitional terms comprising and including are used in the open ended sense in that elements in addition to those enumerated may also be present. Other examples will be apparent to those of skill in the art upon reviewing this document. | A highway road sign is described that is capable of opening and folding to display or conceal information presented on a face of the road sign. The foldable sign of the invention is further capable of being opened and closed remotely and powered with solar energy. Additionally the foldable sign is operable when subjected to cross winds. | 4 |
CROSS-REFERENCES
This application is a continuation in part application of application Ser. No. 08/366,324, Dec. 29, 1994 U.S. Pat. No. 5,613,454 on Mar. 25, 1997.
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for latchtacking the chain of stitches formed at the completion of a work piece into the beginning of the new seam in the next work piece. When sewing, for example the longitudinal seam on a garment sleeve, a seam chain is produced at the completion of the seam that extends from the trailing edge of the garment. This chain is severed from the completed garment piece and the remainder of the chain extends to the needle and other stitch forming implements. The remaining chain, can be folded back upon the top surface of the next garment piece to be sewn. When seaming of the next garment piece commences the remaining chain is covered by the seam. U.S. patent application Ser. No. 08/608,057 discloses, a sewing machine for hemming, folding and seaming garment sleeves. U.S. patent application Ser. No. 08/608,057 is by reference hereby included as a part of this application.
Generally, a sewing machine for forming an overedge chain stitch has a sewing needle, loopers, and a chaining tongue that cooperate to form the thread chain. The sewing machine also includes a presser foot, feed dogs and a throat plate that function to cyclically advance a work piece through the stitch forming region. The chaining tongue, which acts as if a knitting needle around which the thread chain is formed, and is typically part of the throat plate.
In sewing a series of work pieces with a manual, semi-automatic or automatic sewing machine that produces an overedge chain stitch in the work pieces, the sewing machine continues its sewing operation for a time after the work piece has passed through the stitch forming region of the sewing machine. This continued operation of the sewing machine creates a thread chain extending back toward the sewing needles from the trailing edge of the completed work piece.
The thread chain is severed from the completed work piece, after which a portion of the thread chain remains attached to the sewing needle and other stitch forming implements. This portion of the thread chain will then become attached to the leading edge of the next work piece passing through the stitch forming region.
In order to improve the appearance of the finished work pieces and to prevent unraveling of the seams, the portion of the thread chain attached to the sewing needle must be positioned and retained upstream along the line of feed of the sewing needle. The thread chain is positioned so that it will be oversewn into the seam beginning at the leading edge of the next work piece. The process of oversewing the thread chain into a seam at a leading edge of a work piece is known as latchtacking.
There are known devices for retaining and positioning a portion of a thread chain to be oversewn into a seam at the leading edge of a work piece. U.S. Pat. No. 4,038,933 to Marforio includes a vacuum operated device for latchtacking a thread chain. A throat plate includes a longitudinal channel, which extends through the entire length of the throat plate and a chaining tongue. The longitudinal channel is coupled by a conduit to a switching valve. The switching valve is coupled by a second conduit to a vacuum unit. A trim knife is located adjacent to the throat plate.
A disadvantage of the Marforio device is that the vacuum is supplied to the throat plate through the switching valve. The switching valve will typically have small vacuum passageways that may become clogged or partially blocked by lint, dust, thread pieces and the like, which are ingested through the chaining tongue. In addition, the location of the switching valve may increase the distance between the vacuum unit and the throat plate. This increases the time required to obtain vacuum at the chaining tongue after the valve is switched. It is desirable to mount the vacuum source close to the chaining tongue and to precisely control the timing of the application of the vacuum.
Another disadvantage of the Marforio device is that the trim knife is positioned to the right of the straight longitudinal channel. The trim knife trims the edges of the work piece before the work piece reaches the sewing needles. Because the trim knife is positioned to the right of the longitudinal channel, the resulting seam width size may be unacceptable on many work pieces.
U.S. Pat. No. 5,159,889, to Price et al, also includes a vacuum operated device for latchtacking a thread chain. A throat plate includes an air conduit that terminates in an opening at a chaining tongue. The air conduit extends from the throat plate to a vacuum canister, where the air conduit is coupled to an internal control valve assembly suspended from the lid of the canister. When the internal control valve is open, reduced air pressure within the canister draws an air stream through the air conduit. The reduced air pressure within the canister is established by coupling the canister to an inlet conduit of a venturi. The venturi is coupled to a high pressure air line by a valve.
A disadvantage of the Price device is that the vacuum canister is physically large making mounting close to the throat plate difficult. In addition, the vacuum canister requires regular maintenance to remove the lint, dust, thread pieces and the like that are drawn through the opening in the air conduit and into the canister. Furthermore, because vacuum is drawn through the internal control valve assembly, the presence of such debris on the valve element of the internal control valve assembly may prevent the internal control valve from completely closing. It is desirable to mount the vacuum source close to the chaining tongue and to minimize required maintenance.
A further disadvantage of the Price device is that two valves are utilized, the internal control valve assembly and the valve coupling the venturi to the high pressure line. It is desirable to minimize the number of components used in the vacuum system. In addition, the time required to evacuate the canister with this valve arrangement may limit the number of work pieces that can be produced in a given time. Also the chain cutter is located a substantial distance to the rear of the throat plate and as a result the thread chain that must be latchtacked is very long.
Another known device for retaining and positioning a portion of a thread chain to be oversewn into a seam at the leading edge of a work piece is available from Atlanta Attachment Company of Lawrenceville, Ga. The device includes a thin-walled vacuum tube that is soldered to the underside of the throat plate and chaining tongue. The thin-walled vacuum tube is soldered to a vacuum conduit at the front edge of the throat plate.
A disadvantage of this device is that the chaining tongue may not be hardened and polished after the thin-walled vacuum tubing is soldered in place. It is desirable to harden and Polish all surfaces of the chaining tongue because the thread chain is formed around the chaining tongue and should smoothly slide over the chaining tongue. Surfaces of the chaining tongue that have not been hardened are subject to needle nicks, which may cause the thread chain to snag and necessitate replacement of the entire throat plate. In addition, with the thin walled tubing, which is formed and then soldered in place, the chaining tongues on a series of throat plates may not be consistently dimensioned, leading to greater set up times when replacing a throat plate. Furthermore, the vacuum conduit may not be readily reformed or repositioned.
In the prior art the completed garment piece is conveyed along the stitch line, away from the stitch forming region, at a faster rate than the stitch forming rate. This causes the chain that is formed to be stretched. This faster feed rate can be automatically initiated for example by a signal to the operating system that is generated in response to sensing the trailing edge of the completed garment piece. The base of the chain is formed over a hollow chaining tongue that is open at its free end. The typical chaining tongue is formed integral with the throat plate. A vacuum source is connected to the chaining tongue which creates a stream of air that flows in the open end of the chaining tongue. The signal that is generated in response to sensing the trailing edge of the completed garment piece can also activate a cutting device that severs the chain at a predetermined distance from the back edge of the chaining tongue. This usual predetermined distance is approximately an inch which results in quite a long chain that is difficult to control. When the stretched chain is severed it snaps back toward the stitch forming zone. Since the free end of the chain is no longer constrained the portion of the chain at the back edge of the chaining tongue will now be drawn into the open end of the chaining tongue by the air stream. At this time in the cycle the free end of the chain, provided it has not become snagged or tangled, is supported on the upper surface of the throat plate. The length of chain, from the back edge of the chaining tongue to its severed end is then, provided it has not become snagged or tangled, pulled into the hollow chaining tongue by the air stream. When stitching of the next garment begins the thread chain is gradually pulled out of the chaining tongue and the seam being formed covers the chain at the stitch forming region which is located at the base of the chaining tongue. This conventional practice is called latchtacking. For this conventional latchtacking practice to be successful, the loose unconstrained end of the cut chain must be pulled into the open end of the chaining tongue. However, the relative long unconstrained section of chain that snaps back when it is severed often becomes snagged or tangled and as a result is prevented from being pulled into the open end of the chaining tongue. In order to assure proper latchtacking operation a relatively high vacuum differential must be maintained for a relatively long time period. Maintaining this vacuum for the required time period requires substantial power use that increases the operating cost. The long chain, which contributes nothing to the desirability of the finished product, and is a waste of thread. The long thread chain contained in a latchtack in fact detracts from the esthetics quality of the work piece.
When the seam in a work piece is completed and chaining begins the tension on the threads is no longer proper. A thread tension change for the looper thread or threads is required to produce a balanced thread chain. The tension for the needle thread, while producing a seam, is set to feed the proper length of thread to produce an unbalanced stitch. Since the needle thread passes through the fabric it encounters frictional resistance during the stitch forming process. The looper thread or threads on the other hand do not pass throughout the fabric and the resistance on these threads do not change when changing from seaming to chaining. Thus, the tension on the looper thread or threads is adjusted when chaining is initiated causing the stitch chain to be balanced. A balanced stitch chain is more pliable and thus more inclined to be sucked into the opening in the chaining tongue.
Thus, there is a need for a less costly latchtacking technique that is more reliable, and produces a finished work piece that is esthetically superior to the work piece that is produced by the current technique.
SUMMARY OF THE INVENTION
The present invention is directed to an apparatus and method that satisfies the need for a less costly latchtacking technique that is more reliable, and produces a finished work piece that is esthetically superior to the work piece that is produced by the current technique.
An advantage of this invention is that latchtacking can be performed using less power, and waste less thread. Thus, this invention provides a more economical method of producing a latchtack.
Another advantage of this invention is that it is more reliable and as a result of using this invention there will be fewer rejected work pieces.
Still another advantage of this invention is that the resulting finished product is more esthetically pleasing to the consumer.
This invention consist of a chain cutter that cuts a relatively short unstretched chain.
This invention further consist of locating the chain cutter at the back edge of the chaining tongue.
This invention also consist of producing a latchtack that includes a very short chain length and is thus esthetically pleasing.
This invention consist of a method for latchtacking in which the chain is not stretched prior to being cut.
This invention further consist of a method for latchtacking in which stitching ceases prior to the chain being cut.
This invention still further consist of a method for latchtacking in which there is no vacuum in the chaining tongue while the chain is being cut.
This invention consist of producing a latchtack that is more reliable than produced by the prior art latchtacking technique.
This invention also consist of a latching technique in which the tension on the needle and looper thread is adjusted when chaining begins such that a short pliable balanced chain is produced which results in a more reliable technique and a latchtack that is esthetically superior to prior art latchtacks.
The current invention involves a throat plate including a throat plate body having a first internal bore beginning at a front edge of the throat plate body and extending longitudinally there through, and a channel formed in the lower surface of the throat plate body. The throat plate further includes a chaining tongue having a front edge and back edge, where the chaining tongue is integrally formed with the throat plate body. The chaining tongue has a second internal bore beginning at the back edge of the chaining tongue and extends for a distance longitudinally through the chaining tongue and to the throat plate body where the channel couples the second internal bore to the first internal bore.
In another aspect of the invention, a vacuum generating system applies vacuum to the back edge of a chaining tongue at the location of the thread chain cutter. The vacuum generating system includes a source of positive pressure gas, a vacuum generator having an input port, an outlet port and a vacuum port, and a valve for coupling the source to the input port of the vacuum generator. The valve is controllable. The vacuum generating system further includes a conduit coupling the vacuum port of the-vacuum generator to the throat plate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a top view of a throat plate in accordance with the present invention.
FIGS. 1B and 1C illustrate alternative configurations for a vacuum conduit attached to the throat plate of FIG. 1A.
FIG. 1D is a top view of a work piece advancing over the throat plate of FIG. 1A and being trimmed by a trim knife.
FIG. 1E is a view of a partially seamed work piece having a thread chain oversewn into the seam at a leading edge of the work piece.
FIG. 2A is a bottom view of the throat plate shown in FIG. 1A.
FIG. 2B is a bottom view of an alternative embodiment of the throat plate shown in FIG. 2A.
FIG. 3A is a view of a back edge of a chaining tongue on the throat plate shown in FIGS. 1A-1D and 2A-2B.
FIG. 3B is a view of a front edge of the throat plate shown in FIGS. 1A-1D and 2A.
FIG. 3C is a sectional view of a vacuum passageway extending between the back edge of the chaining tongue shown in FIG. 3A and the front edge of the throat plate shown in FIG. 3B.
FIG. 4 is a schematic of a vacuum generating system in accordance with the present invention.
FIG. 5 is a perspective view of an embodiment of the chain cutter mechanism of this invention.
FIG. 6 is a plan view of an embodiment of this invention.
FIG. 7 is a plan view of the preferred embodiment of the latchtacking arrangement of this invention.
FIG. 8 is a timing diagram for the preferred embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention is best understood by reference to the embodiments shown in FIGS. 1A through 4 in which like elements are referred to by like numerals. FIG. 1A is a top view of a throat plate 10 in accordance with this embodiment of the invention. The throat plate 10 has a front edge 12, a back edge 14, a left edge 16 and a right edge 18. Two longitudinal closed slots 20 and 22 are machined into the throat plate 10. Twelve grooves 24, oriented substantially perpendicular to the slots 20 and 22, are cut into an upper surface 26 of the throat plate 10. A screw may be driven through a mounting hole 28 to secure the throat plate 10 to the bed of a sewing machine (not shown). The slots 20, 22 and grooves 24 operatively associate with a presser foot and feed dogs in a conventional manner to cyclically advance a work piece 29, as shown in FIG. 1D, through a stitch forming region 30.
The throat plate shown in the accompanying Figures may be used with a Model 39500 over edge sewing machine manufactured by Union Special Corporation. The Model 39500 over edge sewing machine may produce a class 503 or a class 504 sewing stitch, and may be adapted for manual or automatic operation. U.S. Pat. No. 4,796,552 discloses a sewing machine of the Model 39500 type, and this patent is by reference hereby included as a part of this disclosure. Alternatively, the invention may be adapted for use on other sewing machines, including sewing machines for producing other classes of sewing stitches, to perform the latchtack function.
Referring again to FIG. 1A, a platform 32 extends from the right edge 18 of the throat plate 10. A chaining tongue 34 extends generally toward the back edge 14 of the throat plate 10 from the platform 32. The portion of the throat plate 10 exclusive of the chaining tongue 34 is referred to herein as a body 36 of the throat plate 10. Thus, the platform 32 is part of the body 36 of the throat plate 10.
A trim knife 37 may be mounted adjacent to the body 36 of the throat plate 10 in the notch to the front of the platform 32. Trim knife 37 functions to trim the edges of the fabric being sewn. The trim knife 37 includes a lower stationary blade 39 and an upper moving blade 41. The location of the trim knife 37, as shown in FIG. 1D, in front of the chaining tongue 34 provides a narrow seam width.
The chaining tongue 34 has a back edge 38, which is angled with respect to a line 40 parallel to the back edge 14 of the throat plate 10, as shown in FIG. 1A. The angle between the back edge 38 of the chaining tongue 34 and the line 40 is preferably 8.7 degrees, although other angles may be acceptable. The interface between the chaining tongue 34 and the platform is referred to herein as a front edge 42 of the chaining tongue 34. The chaining tongue 34 also has a right edge 44 and a left edge 46.
As shown in FIG. 1A, the right edge 44 of the chaining tongue 34 angles toward the left edge 46 of the chaining tongue 34 such that the distance between the right edge 44 and the left edge 46 is greatest at the front edge 42 of the chaining tongue 34. The angle between the right edge 44 and a line 48 perpendicular to the platform 32 is preferably 7.6 degrees, although other angles may be acceptable. The distance between the right edge 44 and the left edge 46 is referred to herein as the width of the chaining tongue 34. A needle channel is provided between the right edge 18 of the throat plate and the left edge 46 of the chaining tongue 34. The needle 31 is located in the needle channel at the base of the chaining tongue 34.
FIG. 2A is a bottom view of the throat plate 10 shown in FIG. 1A. The throat plate 10 has a lower surface 50, which is preferably machined in an area 52 along the left edge 16 and the right edge 18 to prevent interference between the cyclically moving loopers (not shown) and the throat plate 10 during the sewing operation.
A vacuum passageway 54 between the front edge 12 of the throat plate 10 and the back edge 38 of the chaining tongue 34 is shown in phantom in FIG. 2A. FIG. 3C is a sectional view of the vacuum passageway 54 extending between the back edge 38 of the chaining tongue 34, as shown in FIG. 3A, and the front edge 12 of the throat plate 10, as shown in FIG. 3B. For sewing machines having the trim knife 37 positioned as shown in FIG. 1A, the vacuum passageway 54 is preferably formed from three interconnected segments.
The first segment is an internal bore 56 within the chaining tongue 34, as shown in FIG. 2A. The internal bore 56 begins at the back edge 38 of the chaining tongue 34 and extends longitudinally through the chaining tongue 34. A longitudinal axis 58 extends axially through the center of the internal bore 56. FIG. 3A is a view of the back edge 38 of the chaining tongue 34 on the throat plate 10 showing an opening 68 on the back edge 38 formed by the internal bore 56. Preferably, the internal bore 56 is formed using an electric discharge machining ("EDM") process.
As shown in FIG. 3C, the chaining tongue 34 has a lower surface 74 with a radius 76 so that the chaining tongue 34 does not interfere with the operation of the loopers (not shown). When the throat plate 10 is used with the Union Special Model 39500 sewing machine, the lower surface 74 preferably is 0.105 inches (0.267 cm) below the upper surface 26 of the throat plate 10 and the radius 76 is approximately 109 inches (0.277 cm). The dimensions are determined by the desired seam width.
The second segment of the passageway 54 is a channel 60 machined into the lower surface 50 of the throat plate 10, as shown in FIG. 2A. The channel 60 intersects the internal bore 56. Preferably, the channel 60 does not extend into the chaining tongue 34, but rather intersects the internal bore 56 on the platform 32. Prior to use of the throat plate 10, the channel 60 is sealed with a cover (not shown), which may be soldered into place or secured by other means, such as a screw. Notably, the cover for the channel 60 does not extend into the stitch forming region 30, and therefore the cover does not contact either the thread chain or the work piece during sewing. Preferably, the walls of the channel 60 are machined so that the cover fits flush with the lower surface 50 of the throat plate 10.
The third segment of the passageway 54 is an internal bore 62 within the body 36 of the throat plate 10, as shown in FIG. 2A. The internal bore 62 begins at an opening 70 on the front edge 12 of the throat plate 10, as shown in FIG. 3B, and extends longitudinally into the throat plate 10, where the internal bore 62 intersects the channel 60. A longitudinal axis 66 extends axially through the center of the internal bore 62. The internal bore 62 may be formed using EDM, drilling or other known machining techniques. Preferably, the internal bore 62 is counterbored at the front edge 12 of the throat plate 10 for attaching the throat plate to a vacuum source. The counterbored portion of the internal bore 62 may be tapped.
Because the vacuum passageway 54 includes the internal bore 56 in the chaining tongue 34, the chaining tongue 34 may be machined from the stock parent metal used for the throat plate 10. Where a throat plate body and a chaining tongue, including the upper and lower surfaces and left and right edges of the chaining tongue, are machined from the same piece of stock parent material, the chaining tongue is referred to herein as being integrally formed with the throat plate body.
Preferably, the parent material for the throat plate 10 and integrally formed chaining tongue 34 is a tool steel, such as S7 tool steel, although any other machinable and heat treatable material may alternatively be used. Since the chaining tongue 34 is integrally formed with the throat plate 10, all surfaces of the chaining tongue 34, including the left edge 46, the right edge 44, the lower surface 74, and the walls of the internal bore 56, may be heat treated and polished, although it is not necessary to heat treat the walls of the internal bore 56. Preferably, the machined throat plate 10 is heat treated to provide a hardness of HV-600 minimum and a core hardness of HRC 42 maximum.
Several advantages are realized by constructing the passageway 54 as described herein. For example, the chaining tongue 34, being hardened on all thread contacting surfaces, is more durable allowing nicks formed on the chaining tongue during its use to be removed by polishing. In addition, throat plates in accordance with the present invention may be machined with chaining tongues having consistent outer dimensions, making the throat plates more interchangeable and producing more consistent thread chains. Furthermore, because the chaining tongue 34 is entirely formed from the parent metal, the walls of the internal bore 56 may be hardened and polished to prevent snagging of the thread chain.
Moreover, because the internal bore 62 within the body 36 of the throat plate 10 provides an attachment point on the throat plate 10 for the vacuum source 64, that is, the opening 70 at the front edge 12 of the throat plate 10, the vacuum source 64 may be coupled to the internal bore 62 using any convenient or desirably shaped conduit 72. More specifically, because the conduit 72 is attached to the passageway 54, as opposed to being integrally formed with the passageway 54, the conduit 72 may be replaced or reoriented without consequence to the chaining tongue 34. Also, differently shaped conduits may be used with the throat plate 10 for different applications requiring auxiliary attachments in front of the throat plate 10. FIGS. 1B, which is a top view of the throat plate 10, and IC, which is a right side view of the throat plate 10, illustrate some of the many alternative ways that the conduit 72 may be oriented.
In alternative embodiments, the vacuum passageway 54 may be formed from two segments. In a first alternative embodiment, shown in FIG. 2B, the channel 60 and the internal bore 62 in the throat plate 10 are replaced by a length of soft steel tubing 63. The tubing 63, shown in FIG. 2B, is essentially formed to match the shape of the channel 60 and the internal bore 62, shown in FIG. 2A. The lower surface 50 of the body 36 is machined to accommodate the steel tubing 63, which is attached to the internal bore 56 in the chaining tongue 34. Thus, the two segments of the vacuum passageway 54 are the length of soft steel tubing 63 and the internal bore 56. In this embodiment, the steel tubing 63 may extend from the throat plate 10 to operate as the conduit 72 to the vacuum source 64. The chaining tongue 34 in the first alternative embodiment is integrally formed with the throat plate 10.
In a second alternative embodiment, the internal bore 56 in the chaining tongue 34 and the channel 60 are replaced by a formed length of soft steel tubing. The lower surface of the chaining tongue 34 and the throat plate 10 are relieved by machining to accommodate the steel tubing, which is attached to the internal bore 62 . Thus, the two segments of the vacuum passageway 54 are the length of soft steel tubing and the internal bore 62 within the body 36 of the throat plate 10.
If the trim knife 37 is not required, the vacuum passageway may be formed in a single segment. In FIG. 1A, the notch along the right edge 18 of the throat plate 10 to the front of the platform 32 may accommodate the trim knife 37. If the trim knife 37 is not required, then the notch may be eliminated and the right edge 18 to the front of the platform 32 extended to the right edge of the platform 32. The vacuum passageway 54 may then be formed by machining a bore extending from the back edge 38 of the chaining tongue 34 to the front edge 12 of the throat plate 10. The passageway 54 is preferably formed using electric discharge machining. As above, the passageway 54 may be counterbored at the front edge 12 of the throat plate 10.
Referring now to FIG. 4, which is a schematic view of a vacuum generating system in accordance with the present invention. The vacuum generating system includes an air supply 78, which provides positive pressure. The air supply 78 is preferably coupled to a regulator 80, which may have a gage 82 or other indicator of the pressure level. The regulator 80 is coupled to a valve 84, which is coupled to a controller. The air supply 78 may alternatively be directly coupled to the controlled valve 84. When the valve 84 is open, air from the air supply 78 flows through the valve 84. When the valve 84 is closed, the air supply is cut off. The valve 84 output is coupled to a vacuum generator 86.
The vacuum generator 86 has an input port 88, an exhaust port 90 and a vacuum port 92. Between the input port 88 and the exhaust port 90, the vacuum generator 86 forms a venturi-with a straight through hole, providing a vacuum at the vacuum port 92. The vacuum generator 86 may exhaust to the atmosphere. A suitable commercially available vacuum generator 86 is supplied by Fabco-Air of Gainesville, Fla. as model VTR-1. A Series HAV Vacuum Transducer Pump as manufactured by Air-vac Engineering Co. of Milford, Conn. may alternatively be used.
The vacuum port 92 of the vacuum generator 86 is coupled by the conduit 72 to the counterbored opening 70 on the front edge 12 of the throat plate 10. Preferably, the lengths of the conduit 72 and the coupling between the vacuum generator 86 and the valve 84 are minimized. As the valve 84 is controllable, close coupling the valve 84 to the vacuum generator 86 reduces the time delay between switching open the valve 84 and obtaining a vacuum at the chaining tongue 34. The valve 84 is preferably a pneumatically actuated poppet valve, although a solenoid actuated valve may alternatively be used. The valve 84 is preferably controlled by a microprocessor having an input from a sensor, such as a retroreflective sensor, located to monitor the position of the work piece. The valve 84 may alternatively be controlled by an operator, who may throw a switch to apply the actuating signal to the valve 84.
In operation, the air supply is coupled to and flows through the vacuum generator 86 upon application of the required pressure to the pneumatically controlled valve 84. The venturi within the vacuum generator 86 generates vacuum at the vacuum port 92 as the air supply flows from the input port 88 to the exhaust port 90. The vacuum is coupled by the conduit 72 to the passageway 54 in the throat plate 10, ultimately reaching the opening 68 in the chaining tongue 34. Preferably, the openings throughout the passageway 54, the conduit 72 and the path through the vacuum generator 86, between the vacuum port 92 and the exhaust port 90, are larger than the opening 68 to prevent the vacuum generating system from becoming clogged by lint, dust, thread pieces and the like.
The vacuum at the opening 68 serves to draw the end of the portion of the severed thread chain that is attached to the sewing needle into the chaining tongue 34. By varying tension on the sewing threads prior to or in the course of chaining off the thread chain, the thread chain may be made more balanced and flexible, as is known in the art. A balanced and more flexible thread chain may be captured by the chaining tongue more consistently. In addition, it is desirable during the latchtacking operation to sever the balanced thread chain very close to the back edge 14 of the throat plate 10 in order to minimize the length of the severed thread chain and to locate the severed end of the thread chain near the opening 68 in the chaining tongue 34.
Alternatively, or in addition to varying tension on the sewing threads, the thread chain may be stretched before it is severed, as is known and described, for example, in U.S. Pat. No. 4,679,515 to Keeton or in U.S. Pat. No. 5,159,889 to Price et al., to assist in directing the portion of the severed thread chain that is attached to the sewing needle toward the opening 68 in the chaining tongue 34. Several stitches may be chained off during or immediately after severing the thread chain to ensure that the proximal end of the thread chain is located about the chaining tongue.
The end of the thread chain is thereby positioned and retained within the chaining tongue 34 until the next work piece 29 enters the stitch forming region 30 of the sewing machine. As the work piece 29 is advanced through the stitch forming region 30, the thread chain is withdrawn from the chaining tongue 34 and oversewn into the seam at the leading edge of the work piece 29. As shown in FIG. 1E, a thread chain 94 is oversewn into a seam 96 at a leading edge 98 of the work piece 29. Preferably, vacuum is supplied by the vacuum generator 86 to the chaining tongue 34 as the advancing work piece 29 draws the thread chain out of the chaining tongue 34.
The throat plate 10, as described above, may be used in automated seaming or hemming and seaming sewing machines, as well as in manual or semi-automatic sewing workstations. As is further described above, the vacuum source 64 is preferably controlled by the microprocessor, which has an input from the sensor, such as a retroreflective sensor, located to monitor the position of the work piece. The vacuum source 64 may alternatively be controlled by the operator, who may throw a switch to apply the actuating signal to the valve 84.
Referring to the drawings, FIG. 5 is a perspective view of the chain cutter 110 that is used in the preferred embodiment of this invention. The blades 112 and 116 of chain cutter 110 are miniature version of a conventional chain cutter of the type that is used with the embodiments of this invention discussed above and illustrated in FIGS. 1A through 4. The size of blades 112 and 116 were reduced to enable the cutter 110 to be located at the free end of the hollow chaining tongue 34 of the throat plate 10. It should be noted that the throat plate 10 as described above is used in this preferred embodiment of the invention.
The chain cutter 110 includes a stationary knife 112 that is secured by a fastener such as a screw 113 to an end portion of the cast cutter frame 114. The cast cutter frame 114 is secured to the cutter bracket 126 which is fixedly secured to the sewing machine frame. The movable knife 116 is carried at the first free end of a shaft 118. Shaft 118 is supported for rotation in cylindrical openings formed in lugs 115 that are integral with the cast cutter frame 114. A collar 119 is secured to shaft 118 between lugs 115 that serves as an adjustable stop for one end of a compression spring 120. The other end of compression spring 120 bears against one of the lugs 115 such that the movable knife 116 is biased into engagement with stationary knife 112. A link 121, which is one half of a clevis, is secured to the second free end of shaft 118. Link 121 is pivotally connected by a clevis pin 122 to link 123 which is the other half of the clevis. Link 123 is secured to the free end of a piston shaft 124 that reciprocates in the cutter cylinder 125. Cylinder 125 is mounted for articulation on the cutter bracket 126. When cylinder 125 is energized the piston shaft is extended which causes the clevis links 121 and 123 to move about clevis pin 122. The movement of link 121 imparts an articulation of shaft 118 in the cylindrical openings formed in lugs 115.
FIG. 6 is a top view illustration of the embodiments of this invention that are discussed above and illustrated in FIGS. 1A through 4. In this view the throat plate 10, hollow chaining tongue 34 and its back edge 38 are identified. Also identified in this view is the work piece 129 that has been completed, with the thread chain 94 that extends from the trailing edge 198 of completed work piece 129 to the needle and other stitch forming implements. In FIG. 6 stationary knife 112 and the movable knife 116 are located rearwardly of the back edge 14 of the throat plate 10. In FIG. 6 the length of chain 94 that extends from the back edge 38 of chaining tongue 34 to the location where chain 94 is severed by knife blades 112 and 116 is identified by the letter X, which is approximately 0.762 inches or 0.0195 centimeters.
FIG. 7 is a top view illustration of the preferred embodiments of this invention in which the blades 112 and 116 of chain cutter 110 have been miniaturized. In this view the throat plate 10, hollow chaining tongue 34 and its back edge 38 are identified. Also identified in this view are the work piece 129 that has been completed, the thread chain 94 that extends from the trailing edge 198 of completed work piece 129 to the needle and other stitch forming implements. In FIG. 7 the stationary knife 112 and movable knife 116 are located at the back edge 38 of the chaining tongue 34. In FIG. 7 the length of chain 94 that extends from the back edge 38 of chaining tongue 34 to the location where chain 94 is severed by knife blades 112 and 116 is identified by the letter Y which is approximately 0.110 inches or 0.0028 centimeters. Thus, in the preferred embodiment the severed chain length has been reduced from 0.762 inches to 0.116 inches. which represents a reduction of 693%. As a result of this reduction it is no longer necessary to stretch the chain before it is cut and the loose unconstrained section of chain extending from the back edge 38 of the chaining tongue to the back edge of the throat plate 10 has been eliminated. The elimination of this loose section of chain has also eliminated the possibility that this loose chain will become snarled or tangled. Furthermore, the length of chain that must be latchtacked into the seam of the next work piece has been greatly reduced which improves the appearance of the finished product.
FIG. 8 is a timing diagram for the preferred embodiment of this invention and discloses the current best mode of the invention. However, some of the sewing machine components and their sequence of operation are, as disclosed in the current best mode, are not necessary or could be varied without affecting the practice of applicants invention. For example the feed belt could be eliminated or it could remain in the down position throughout the cycle. A column at the left side of this diagram contains the names of a number of the mechanical components that play a roll in the latchtacking process. Each of these components is connected to the sewing machine's central processor. The central processor receives and sends signals to and from the components and can be programmed to send a signal a predetermined time periods after receiving a signal. The time delays can be measured either in units of time or in stitches produced by the sewing machine.
The first component in the timing diagram is labeled SEW/LATCHTACK SENSOR. This sensor is uncovered until a work piece to be stitched approaches the stitch forming region. When the approaching work piece reaches the SEW/LATCHTACK SENSOR the sensor is covered and the sequence begins. The next component is the PRESSER FOOT which is either down or up. When the sensor is covered a signal is sent to the central processing unit which responds by sending a signal to lower the presser foot to the down position. It should be noted that the presser foot is not raised to the up position as soon as the sensor is uncovered, rather there is programmed into the central processing unit a predetermined presser foot up delay. This delay compensates for the time it took the leading edge of the work product to advance from the spot that it covered the sensor to when it reached the stitch forming region. The next component on the left is the side feed belt lift mechanism. The feed belt is one of the mechanisms that feeds the work piece during the seaming process. The feed belt is moved to its down or operative position in response to the work piece covering the sensor. The next component on the left is the SEW MOTOR. The central processing unit is programmed to turn the sew motor on after a predetermined delay following the covering of the sensor. Next, skipping down to the second from last component on the left is the stitch tongue vacuum. The stitch tongue vacuum, also referred to above as the chaining tongue vacuum, is turned on prior to turning on the sew motor. Thus, the stitch chain that was severed from the previous work piece will be drawn into the opening in the chaining tongue before the sew motor is turned on. However, this timing could be changed to cause the stitch chain to be drawn into the chaining tongue at the same time or after the sew motor is turned on. On the column of components at the left of the diagram, following the sew motor is the motor run signal. The motor run signal is delayed a predetermined time period after the sew motor is turned on and stays on for a time period, depending upon its braking rate, after the sew motor is turned off. At, a predetermined time period after the leading edge of the work piece was sensed the THREAD TENSION MODE is changed from chaining to sewing. This change is time to begin at the same time that seaming begins. The THREAD TENSION MODE is changed from sewing to chaining after a predetermined time period. This predetermined time period of course corresponds to the time period or the number of stitches required to completed the seam in the work piece. It should be noted that the presser foot is down at the instant that the thread tension mode is changed to chaining but is raised a very short period thereafter. A signal is then sent to turn the sew motor off. At this time in the cycle the side feed belt is down and running and is thus functioning to convey the work piece. At about the same time that the signal is sent to turn the sew motor off the drive to the side feed belt stops. However, the side feed belt is not raised at this time. As a result the side belt is now functioning to stop movement of the work piece. The motor continues to run for a short time period depending upon its braking rate. It should be noted that when the motor run signal stops the central processing unit knows that the sewing head has stopped. When the central processing unit ceases to receive a motor run signal, the central processing unit sends a signal to actuate the chain cutter. Thus, the chain can not be cut until after the motor run signal has stopped and caused a signal to be sent to actuate the chain cutter. After a predetermined time delay following cutting the chain the STITCH TONGUE VACUUM is again turned on. The STITCH TONGUE VACUUM remains on for a predetermined time period and is then turned off. A complete cycle of stitching a work piece beginning with a latchtack has now been completed.
Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. As such, it is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is the appended claims, including all equivalents thereof, which are intended to define the scope of the invention. | An apparatus and method is provided for a less costly and more reliable latchtacking technique that produces a finished work piece that is esthetically superior to the work piece that is produced by the current technique. A chain cutter has miniaturized cutting blades located at the back edge of the chaining tongue such that a relatively short unstretched chain is cut. The chain is not stretched because, stitch Also at the time the chain is cut, the vacuum in the hollow chaining tongue has been turned off. The tension on the needle thread is adjusted when chaining begins such that a short pliable balanced chain is produced which results in a more reliable technique and a latchtack that is esthetically superior to prior art latchtacks. | 8 |
FIELD OF THE INVENTION
[0001] This disclosure relates to the field of on line paid search advertising and more particularly to a methodology for paid search ad agencies servicing local businesses to determine which of the possible thousands of paid search terms and words provide the best ad spend return for the business they are servicing and the appropriate amount of ad spend to capture the particular local market they are servicing.
BACKGROUND
[0002] Online search powered by Web-based search engines has proven to be one of the most common methods used by consumers and businesses to find and purchase both products and services. Online search providers such as Google, Bing, and Yahoo! now have the ability for a local business to purchase search based ad content that only pertains to the local businesses geographic location.
[0003] The economy is made up of millions of local businesses who are potential purchasers of local search based ad content. These local businesses have established web sites to promote the products and/or services they provide to the local community. Online paid search advertising is on a path to quickly surpass previous forms of advertising local businesses used to reach potential clients such as phone book advertising. The online search providers have employed a system to sell their search based advertising which at first seems quite simple for a local business to deploy and purchase. However, local businesses do not typically have the ability to analyze all of the thousands of possible search terms and phrases to develop an effective local paid search ad campaign. Difficulties include determining how to establish a correct budget for the desired results, how to analyze changing local paid search trends, and how to determine which terms and words actually provide a return on their advertising investment. However on a national level, these local businesses typically fall into a certain category. Local businesses all across the country in this category share common terms and phrases related to their specific business. Local businesses also share several types of customer groups who represent different levels of profit and ongoing profit potential for the local business. Online search providers provide back to the paid advertiser a great deal of data. Never before in the history of advertising has there been such a large amount of raw data available to the individual business related to their paid search advertising campaign. This data comes from both the analytic tools the local business may place on their website and the providers of paid search advertising. However the ability to properly analyze this data is beyond the reach of the local business owner. Local business owners typically make a guess on several things including key search terms, negative search terms, and ad budget. Local business owners do not have a method to take the data fed back to them from the results of their self run campaign to properly analyze the results. A need exists to provide local business owners with a mathematical strategy to develop a paid local search based advertising campaign.
SUMMARY
[0004] In one aspect, a method and system disclosed herein includes gathering data pertaining to a national category of business and in addition data received from on line search providers, calculating the value of at least in part on terms, words, phrases to the local business owner to develop a target budget and key word campaign for a local paid search campaign across any number of online search ad providers.
[0005] A local business owner wishing to embark on a paid search advertising campaign has one of two choices: i) attempt to design and run the campaign themselves or ii) pay an outside agency to run the campaign. The local business owner may know his field better than an outside agency. An outside agency may have a better understanding of paid search advertising due to trial and error experience.
[0006] A method to categorize the local business owner into a national vertical segment will reveal words, terms, and phrases consumers and businesses use to seek out providers of this vertical segment. High value target terms, words and phrases will be established through methods including data analysis and interviews with other local business owners at a national level in the same vertical segment. For example a potential local customer searching for the term Lexus is quite valuable to the local business selling the Lexus brand, but has very little value to the local business selling appliances. However for the local business selling a competing brand such as BMW, the Lexus search term would have a high value. Furthermore, a local business engaged in repair of the Lexus brand would consider the search term “Lexus repair” to have a very high long term value in capturing a potential repeat customer.
[0007] Certain categories of products sold by local businesses have a higher profit margin than other products sold by the same local business. These categories of products have words, terms, and phrases associated with them. For example, a local audio/video business may engage in selling expensive high profit home theater systems and also engage in selling low margin, low priced televisions. A search term such as “best home theater system” has a higher value to the local audio/video business than the search term of “televisions”. Furthermore, the search term of “cheap televisions” may have no value at all to the local audio/video business and a negative term may be employed in the paid search terms to prevent any type of ad for their business being presented to a customer searching for “cheap televisions.”
[0008] Furthermore, some search words, terms, or phrases may be very specific to the local business in a category, yet are not widely searched terms. An example of this may be a search term such as “best Maserati dealer in Utah”. This combination of search terms may have a very low cost to allow the ad to be displayed across paid search providers, but this potential client would have a high value to the Maserati dealer in Utah.
[0009] All of the potential paid search words, terms, and phrases, including negative phrases which prevent an ad from showing can be captured in a relational database that links to the specific national business category the local business exists within. A weighted index number can then be assigned to each potential word, term, or phrase used in a paid search ad based upon the national category the local business falls within.
[0010] Data from the providers of paid search advertising such as Google, Bing, Yahoo!, and others will reveal the estimated market price for high positioning of paid search ads based upon the various geographic locations. High positioning of paid search ads is desired by the local business to present their ad to potential clients searching for providers of their product or service. Furthermore data from the paid search providers will reveal the inventory of search ads available in a specific local geographic area. Both of these data sets are changing every minute and can be constantly updated with real time information.
[0011] Data from the providers of paid search advertising such as Google, Bing, Yahoo!, and others is available in real time to measure the effectiveness of both paid search words, terms, and phrases and the positioning of these words, terms, and phrases based both on the local ad being shown to the local potential customer and the rate of clicks to the promoting website of the local business by the potential local customer.
[0012] Multivariate analysis can be used across a set of relational data bases to establish the target budget for the local business falling into a national category, based upon their geographic location, and the national category. On going updates to the data bases, from the providers of the local paid search ads can be fed back into the data bases as related to providing enough ad spend for the ad to be shown, positioning of ads, and click through rates of the ad to the local businesses web site. This analysis can then adjust the ad spend budget and words, terms, phrases and keyword bid rates based on real time local data that relates to the local business. Data trends can be found on a national level as they relate to search words, terms, and phrases as the market within the national category may evolve.
BRIEF DESCRIPTION OF THE FIGURES
[0013] The invention and the following detailed description may be understood by reference to the following figures:
[0014] FIG. 1 illustrates a generalized method to establish a vertical master list.
[0015] FIG. 2 illustrates a method to establish a set of negative terms for a vertical master list.
[0016] FIG. 3 illustrates a generalized method to develop a connected set of key words, terms, and phrases with related negative key words, terms, and phrases (word groupings).
[0017] FIG. 4 illustrates a generalized method to place a value in several categories on each word grouping.
[0018] FIG. 5 illustrates a mathematical method to derive an index value for each word grouping.
[0019] FIG. 6 illustrates a method to project a local cost for a preferred ad position for each word grouping.
[0020] FIG. 7 illustrates a generalized method to add local specific word groupings and use a mathematical method to obtain an index factor for the local specific word groupings.
[0021] FIG. 8 illustrates a mathematical method to derive a total suggested budget for a local individual business search based ad campaign.
[0022] FIG. 9 illustrates a generalized process to obtain an actual budget from an individual local business and from there to use a mathematical method to derive a target word grouping and target bid price for each word grouping.
[0023] FIG. 10 illustrates a method to analyze real time results of the individual local business ad campaign and feed these results into a mathematical method to obtain a local index score for word groupings, which through a mathematical method derives a revised target word grouping and revised target paid search campaign budget.
DETAILED DESCRIPTION
[0024] The methods and systems disclosed herein relate to the domain of paid local on line search campaigns for local businesses.
[0025] FIG. 1 represents a method 100 to derive a list of terms and phrases 104 that relate to a specific category of business 101 . The method 100 is a manual interview process 102 with person or persons having detailed knowledge of the specific category of business 101 . The specific category of business 101 may be any type of business where there may be other businesses in this same category across a large geographic region. The interview process 102 generates a list of terms and phrases which are refined by a data analysis method 103 to construct a vertical master list 104 of terms and phrases related to a specific national business category 101 . The method 100 may be applied to any category of business. In embodiments, the vertical master will be all terms and phrases that could be used in a search that could be associated with products and services related to the specific category of business. Terms and phrases that could possibly not be related to the specific business will be removed through the data analysis method.
[0026] FIG. 2 represents a method 109 to derive a list of negative terms and phrases 105 . A term or phrase found in the vertical master list 104 when input into a search engine in combination with a term or phrase not found in the vertical master list 104 may result in an undesirable search result. The search engines 107 such as Google, Bing, Yahoo!, and others provide a set of tools 106 used to determine other terms and phrases related to a searched term or phrase 104 . These other terms and phrases may have a negative impact on the desired outcome of a paid search within a local business paid search campaign 147 . These undesired other terms and phrases are input into the vertical master negative terms list 108 . In embodiments, the negative terms and phrases may be obtained by a manual method of entering each of the terms and phrases in the vertical master list 104 and comparing them to the existing terms and phrases in the vertical master list or an automated data query method of the search engines.
[0027] FIG. 3 represents a method 109 to derive a list of keyword terms and phrases in addition to a list of relevant negative terms and phrases 111 . The method 109 is a manual interview process 110 with person or persons having detailed knowledge of the specific category of business 101 . The interview and analysis method 110 will confirm or deny with person or persons having detailed knowledge of the specific business category 101 that the negative terms and phrases 108 derived with search engine 107 tools 106 are an accurate data set. The interview and analysis 110 generates a list of keyword terms and phrases in addition to a list of relevant negative terms and phrases 111 . In embodiments, this method 109 involves comparing with the specific industry expert or experts every related term or phrase derived from the method in FIG. 2 that could be a possible negative term of phrase. A negative term or phrase when entered into a search engine with a desired term or phrase could yield a search result not relevant to the specific business category. In embodiments, the negative terms and phrases will be used in conjunction with the desired terms and phrases in an ad campaign for individual businesses in the specific national business category. These negative terms and phrases will prevent on line ads from being displayed if the negative term or phrase was entered by the party entering data into a search engine.
[0028] FIG. 4 represents a method 112 to add related data to the keyword terms and phrases 111 . A relational database 118 is built which links each individual term or phrase 113 to factors that influence the value of the individual term or phrase 113 . The interview and analysis process 110 includes several questions about each individual term or phrase 113 . The answers to these questions are typically obvious to someone with experience in the individual business category. Related product margin 114 refers to the profit percent typical of products or services shown when an on line search is done for that individual word or term 113 . Related selling price 115 refers to the total dollar selling price typical of products or services shown when an on line search is done for that individual word or term 113 . Related customer value 116 refers to a scale of long term potential value of a person or persons typically searching for the individual word or term 113 . Other relationships 117 may exist for the individual search word or term and may include but not be limited to relevant industry news about the individual search word or term 113 , reputation of any products or services linked to the individual search term or phrase 113 , and data search trends of the individual search word or term 113 . The method 112 results in a large database of information linked to each individual search word or term. An example of one row of the database 118 is shown in FIG. 4 . All fields in the database 118 with the exception of the individual word or term 113 are assigned a statistical value. In embodiments, the related profit margin, related selling price, related customer value, and other attributes are used to assign values to each of the search terms and phrases. In embodiments, these values may vary from one specific national business to another. In embodiments, these values are assigned through a series of interviews with experts or experts related to the specific national business category.
[0029] FIG. 5 represents a mathematical method 119 using multivariate analysis to derive an index factor 125 for each individual search term or phrase 113 . The weighting factor 120 for related profit margin 114 is assigned the same statistical value across the database for the individual national business in the same category FIG. 1 101 . The weighting factor 121 for related selling price 115 is assigned the same statistical value across the database for the individual national business in the same category FIG. 1 101 . The weighting factor 122 for related customer value 116 is assigned the same statistical value across the database for the individual national business in the same category FIG. 1 101 . The other weighting factors 123 for other related values 117 are each assigned the same statistical value across the database for the individual national business in the same category FIG. 4 101 . The statistical values assigned to each weighting factor will vary from individual national business FIG. 4 101 . to another. Using multivariate analysis 124 , an index factor 125 is calculated for each individual search term or phrase in the relational database FIG. 4 118 for the individual category of business FIG. 4 101 . In embodiments, this statistical method weighs the various characteristics of the search terms and phrases to derive a true value of the search term or phrase as it relates to other possible search terms and phrases of the same specific national business category.
[0030] FIG. 6 represents a method 126 to project a local target cost for preferred ad position 128 for each individual search term or phrase in a specific geographic area. Bid rates for the same individual search term or phrase vary widely across geographic regions. Using the local analysis tools 127 provided by the national search engines 107 , a projected cost for preferred ad position 128 can be derived for each individual search term or phrase 113 . The projected cost for preferred ad position 128 for each individual search term or phrase 113 populates a field in the relational database FIG. 4 118 . In embodiments, a manual or automated tool may be used to enter each of the various search terms and phrases along with the related negative terms and phrases into the advertising tools provided by national search engines to derive the estimated local cost, specific to each geographic region, of having the national search engines display an ad related to these search terms and phrases in a preferred position.
[0031] FIG. 7 represents a method to derive a specific list of search terms and phrases for an individual business from the national specific business category the individual local business falls within and to add local specific search terms 133 or phrases to a database for each individual local business 130 and to derive using multivariate analysis 124 an index factor 125 for each of the local individual business specific search terms and phrases 133 and to derive a projected target cost for preferred placement for each of the individual local business terms and phrases. Using a business process 131 , each individual local business 130 is interviewed. All of the national search terms and phrases 134 are discussed with the individual local business. Not all of these national terms and phrases will be relevant to the individual local business 130 due to many factors including product line differences within the same category and or the fact the individual local business may not specialize in all areas of this specific national business. The business process 131 will eliminate for the specific individual local business 130 any of the national terms and phrases 134 that are not relevant to the individual local business 130 . This data set becomes the individual local business target word list 132 . During the business process 131 certain local specific search words and phrases 133 may be derived. These local specific terms and phrases 133 may be geographic terms and phrases, local slang or colloquialisms, terms and phrases related to unique products or services the individual local business provides, or any other terms and phrases uniquely linked to the individual local business. This data set of unique local terms and phrases 133 is processed with the same method used in FIG. 4 112 to add related data to terms and phrases related to the individual local business. Using the same mathematical method shown in FIG. 5 119 , a weighting factor is assigned to each of the related terms including profit margin 114 , selling price 115 , customer value 116 , and other relationships 117 . Using multivariate analysis 124 an index factor 125 is assigned to each individual term or phrase in the local individual business specific terms and phrase database 133 . Using the same method represented in FIG. 6 126 , each of the local individual business specific terms and phrases 133 is assigned a projected cost for preferred ad position 128 . In embodiments, this method is used to possibly reduce the size of the list of all terms and phrases for a specific national industry to only those terms and phrases that relate to the products and or services provided by the specific local business. In embodiments, the interview method is used to derive any other terms and phrases that may relate specifically to the individual business. In embodiments, this statistical method weighs the various characteristics of the specific search terms and phrases related to the individual business to derive a true value of the search term or phrase as it relates to other possible search terms and phrases of the same specific national business category. In embodiments, a manual or automated tool may be used to enter each of the local specific to the individual business search terms and phrases along with the related negative terms and phrases into the advertising tools provided by national search engines to derive the estimated local cost, specific to the geographic region of the local business, of having the national search engines display an ad related to these search terms and phrases in a preferred position.
[0032] FIG. 8 represents a method 135 to derive a suggested advertising budget for paid local search 138 using multivariate analysis 139 for a specific individual local business FIG. 7 130 . The method applies multivariate analysis 139 to the refined national terms and phrase list 132 , the individual local business specific terms and phrase list 136 , the index factor 137 derived by the method represented in FIG. 5 119 , and the projected target cost for preferred ad position 128 for each of the terms and words in both the refined national terms and phrase target list 132 and the individual local business specific terms and phrase list 136 . The analysis produces a suggested ad spend budget 138 for the individual local business. In embodiments, this is a method to derive, an estimated search engine advertising ad budget for a specific local business. In embodiments, the terms and phrases from the national list that relate to the specific local business, the terms and phrases that relate only to the specific local business, the estimated cost of displaying these search terms in preferred position, and the relative importance of each of these terms and phrases are all entered into a multivariate analysis tool to derive the total estimated advertising budget needed for the specific local business.
[0033] FIG. 9 represents a business process 140 to refine an on line search ad spend budget for an individual local business 130 . Using this refined budget, multivariate analysis 143 is applied to find the target word group list 144 and target bid price 145 for each of these individual terms and phrases 132 , 136 . The suggested ad spend budget derived using the method 135 described in FIG. 8 may or may not exceed the ad spending ability of the individual local business. A budget business process 141 with the individual local business 130 will determine an on line ad spend budget 142 that fits the current spending ability of the individual local business. Using multivariate analysis 143 on the individual local business target word group list derived from national list 132 , the individual local business unique local target word group list 136 , the index factor for each word group in each target list 137 , and the local projected cost for preferred ad position 128 for each word group in each target list derives a list of target terms and phrases 144 and a suggested bid price for preferred ad position 145 for each of these suggested terms and phrases 144 that match the ad spend budget 142 of the individual local business 130 . In embodiments, the method derives an optimal set of search terms and phrases for the individual local small business to place paid search bids on that will match the small business budget needs. In many cases, most businesses will not be able to spend up to the recommended spend level for optimum placement for all of the possible search terms and phrases that relate to their specific category of business. In embodiments, a business interview process with the local business determines a budget for the local business. The need exists to determine which search terms and phrases related to the individual business would generate the largest pool of potential profitable customers. In embodiments, the method uses multivariate analysis to derive the list of search terms and phrases while also establishing a suggested bid price where the combination of search terms and phrases coupled with the suggested bid price should closely match the budget determined in the interview process. In embodiments, the interview business process occurs on a daily, weekly, monthly, or other seasonal time frame and can be used to derive a new set of search terms and phrases with their suggested bid price at any time.
[0034] FIG. 10 represents a method 162 to continually refine the target word group list 159 for the individual local business FIG. 8 130 and the target price for preferred ad placement 160 of the target word group list. An individual local business FIG. 8 130 will run a paid search campaign 147 with one or more paid search providers. These paid search providers generate detailed data results 149 related to the success of the paid search campaign of the individual local business. This data may consist of total impressions for each individual search term or phrase 151 , total clicks on each individual ad for each individual search term or phrase 152 , average cost per ad click 153 , positioning of the individual ad 154 , a score from the paid search provider on the individual ad 155 , and other related data 156 . The individual local business will have a website 146 the ad clicks are directed to. The website will have tools 161 embedded in the website to track many details related to clicks to the website including but not limited to, time spent on the web site, pages visited on the web site, geographic location of the user clicking on the ad and more. Both the data from the paid search providers related to the individual local business paid search campaign and the data from the individual local business website are entered into a relational database. Based on this data, multivariate analysis 157 is used to obtain an additional index value known as the local index value 158 . This is an individual value for each of the search terms and phrases of the individual local business paid search campaign. Using the additional index value 158 and multivariate analysis 157 a refined suggested ad budget 160 is calculated and in addition a refined list of search terms and phrases 159 suggested for the individual local business. In embodiments, this method uses all of the data available to the individual business to refine the advertising campaign based on multivariate analysis. In embodiments, the method described may or may not run in real time, daily, weekly, monthly or any other cycle. In embodiments, this method may be used to provide the individual local business with recommended paid on line search budgets based upon changing conditions.
[0035] In embodiments, the methods of this invention use national business category experts, multivariate analysis, and individual local specific business interviews to derive an optimum on line paid search advertising campaign for a specific local business. In embodiments, the data provided by both the national search engines and the individual local business web site are used with multivariate analysis to refine the on line paid search ad campaign of the individual local business. | Local businesses using on line search advertising to attract customers have a difficult time determining the effectiveness of various search terms or how much to bid for each term or search phrase. Local businesses typically fall into a national category. This national category has words and terms related to it which consumers and businesses use to search for providers and information within the category. Multivariate analysis can be used across target words and terms, negative words and terms, product profit margin, product sales volume, customer value, and click thru success to determine an index value for each search term. This analysis can be used to determine the best potential ad budget for a paid search campaign and the best phrases to deploy and optimal bid rates. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention claims priority under 35 U.S.C. § 119 of German Patent Application No. 196 23 652.5 filed on Jun. 13, 1996, the disclosure of which is expressly incorporated by reference herein in its entirety.
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention claims priority under 35 U.S.C. § 119 of German Patent Application No. 196 23 652.5 filed on Jun. 13, 1996, the disclosure of which is expressly incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a deflection adjustment roll that includes a rotating roll jacket, a support member that axially passes axially through the roll jacket, and a plurality of support elements, e.g., hydrostatic and/or hydrodynamic support elements, disposed next to one another and spaced apart in an axial direction of the roll. The support elements may support the roll jacket on the support member via a fluid cushion formed between support member and the roll jacket. A fluid removal apparatus may be provided for removing operating fluid, e.g., lubricant, from a portion of an interior surface of the roll that collects on the interior surface of the roll during operation. The operating fluid collected on the interior surface of the roll may form a fluid ring that circulates around the support elements on an inner circumference of the roll jacket.
2. Discussion of Background Information
In a deflection adjustment roll of the prior art, operating fluid, in particular oil, supplied, e.g., via the support elements must be removed again from the interior portion (inner side) of the roll. When a deflection adjustment roll having support elements located adjacent the top inside surface of the roll is utilized as a bottom roll, the operating fluid can be wiped from the interior portion of the roll jacket by the support elements and can be discharged in a manner supported by gravity. However, a deflection adjustment roll having support elements located adjacent the bottom inside surface of the roll cannot be utilized as a bottom roll, and, when utilized as a top roll, e.g., as disclosed in DE 25 50 366 A1, a reservoir is located between the yoke and an end section of the roll jacket.
In the deflection adjustment rolls of the prior art, it is particularly problematic that relatively thick oil rings can form in the roll, which in turn bring high splash-induced power losses that occur, e.g., when circulating around the support elements.
SUMMARY OF THE INVENTION
An object of the present invention may be to produce a deflection adjustment roll of the type discussed above such that fluid quantity contained on an interior portion of the roll and correspondingly, splash-induced power losses associated with the fluid quantity, may be easily and reliably reduced to a minimum.
The above object may be achieved according to the present invention by a plurality of fluid stripping elements formed on the support elements as part of a fluid removal apparatus. The stripping elements may laterally protrude from each support element in a direction of a neighboring support element and strip the fluid circulating around the support elements from the interior surface of the roll jacket in flow channels formed between the support elements.
In this embodiment, the support elements and the fluid stripping elements provided on the support elements may act concertedly on the fluid entrained by the roll jacket and circulating around the support elements. The fluid stripping elements may optimize an oil quantity that can be stripped so that the fluid quantity contained on the inner surface of the roll may be reduced to a predetermined minimum. Thus, the fluid film coatings formed on the inside surface of the roll may be kept sufficiently thin and, correspondingly, the splash-induced power losses that occur due to the fluid circulation around the support elements are slight.
According to a preferred embodiment, the fluid stripping elements may be at least partially located and/or formed such that they are only active when the deflection adjustment roll is utilized as a bottom roll, i.e. when the support elements (and the fluid stripping elements) are positioned in an upper half of the roll. Consequently, the fluid stripping elements may remain inactive when the deflection adjustment roll is utilized as a top roll, i.e. when the support elements (and the fluid stripping elements) are positioned in an oil sump located or formed at a bottom of the roll.
As is known in the art, when used in a same machine, different rotation directions for the roll jacket are produced when a deflection adjustment roll is used as a top roll as opposed to a bottom roll. Thus, according to the present invention, fluid stripping elements may be suitably located and/or formed to only be active when the roll jacket rotates in one direction and to remain essentially inactive when the roll jacket rotates in the opposite direction.
Therefore, according to a particular embodiment of the present invention, the support elements may be simply formed as round elements and the fluid stripping elements, which may be formed, e.g., as blade-shaped, may radially protrude radially from the support elements. The fluid stripping elements, when active, may be located in an upstream region of the support elements with respect to a direction of rotation of the roll jacket, i.e., a region oriented toward the circulating fluid ring, and may be directed counter to a circulating direction of the fluid ring. Conversely, the fluid stripping elements, when inactive, may be located in a downstream region of the support elements, i.e., remote from the circulating fluid ring, and may be directed in the circulating direction of the fluid ring.
Each of the tips of the fluid stripping elements may be advantageously coupled to respective support element, e.g., by a substantially horizontal strut to reduce a flow resistance of the active fluid stripping elements. Accordingly, the struts may respectively extend from the tips of the fluid stripping elements into a region of a central axis of the support elements extending parallel to the roll axis.
According to a preferred embodiment, two fluid stripping elements may be located on opposite sides of each support element and, e.g., may be formed as symmetrical to the central axis of the support element extending perpendicular to the roll axis.
In order to deliberately strip away the fluid rings formed or produced from the fluid entrained by the roll jacket that circulates around the support elements, particularly when the fluid stripping elements are inactive, scraper elements are provided adjacent the inner circumference of the roll jacket and axially positioned along the length of the roll jacket to include spaces associated with the support elements. In this embodiment, the fluid stripping elements deliberately act on the discrete fluid rings produced by fluid entrained by the roll jacket that circulates around the support elements. Therefore, the fluid quantity contained on the inner surface of the roll jacket may be reduced to a minimum. At the same time, friction losses may be kept low, even in comparison with rolls using a continuous stripping blade.
According to a preferred embodiment, an axial length of the scraper elements may be greater than a distance between the support elements. This enables the scraper elements to remove the discrete fluid rings from the inner circumference of the roll jacket over its entire length. It is noted that, after leaving the flow channels formed between the support elements, the discrete fluid rings may become somewhat wider. The scraper elements may also be active when the fluid stripping elements are active, so as to strip the narrow fluid rings flowing (or formed) between the active fluid stripping elements from the inner circumference of the roll jacket.
In a preferred embodiment, at least one fluid discharge may be associated with the fluid stripping elements and/or the scraper elements for fluid discharge supported or assisted by gravity. Thus, relatively costly mechanisms and/or devices for aspirating the discharged or removed fluid may be eliminated.
Furthermore, at least one air deflection plate, that forms a gap with the roll jacket, may precede the fluid stripping elements and/or the scraper elements. The at least one air deflection plate may be sized so that the operating fluid entrained by the roll jacket may pass through, but only a slight amount of border layer air entrained within the operating fluid by the roll jacket may pass through. Accordingly, the fluid stripped by the fluid stripping elements or the scraper elements may flow away smoothly and is not stirred up by any air entrained by the roll jacket. In this regard, this feature may be satisfied by a gap of only a few millimeters.
The present invention may be directed to a deflection adjustment roll that includes a rotating roll jacket, a support member axially extending through the roll jacket, a plurality of at least one of hydrostatic and hydrodynamic support elements located next to one another with a predetermined spacing in an axial direction of the roll jacket to support the roll jacket on the support member, and a fluid removal device that removes operating fluid collected on an inner surface of the roll jacket during operation and that forms a fluid ring that circulates around the plurality of support elements on the inner surface of the roll jacket. The fluid removal device may include a plurality of fluid stripping elements formed on the plurality of support elements that laterally protrude from each support element in a direction of a neighboring support element to strip the fluid circulating around the plurality of support elements from the roll jacket in the flow channels formed between the support elements.
According to another feature of the present invention, the plurality of fluid stripping elements may be at least one of partially located and formed to be active only when the roll jacket rotates in one direction and to remain substantially inactive when the roll jacket rotates in an opposite direction.
According to another feature of the present invention, the plurality of support elements may include round support elements and the plurality of fluid stripping elements may protrude in a substantially radial direction from the plurality of support elements. When active, the plurality of fluid stripping elements may be located on an upstream region of the plurality of support elements relative to the one direction to be oriented toward the circulating fluid ring and are directed against a fluid flow, and, when inactive, the plurality of fluid stripping elements may be located on a downstream region of the plurality of support elements relative to the opposite direction to be remote from the circulating fluid ring and are directed into the fluid flow.
According to a further feature of the present invention, the plurality of fluid stripping elements may include tips coupled to a respective support element by reinforcing struts extending approximately in the fluid flow direction to reduce a flow resistance of the plurality of fluid stripping elements when inactive. Further, the reinforcing struts may be coupled substantially tangent to an outer circumference of the respective support element.
According to still another feature of the present invention, two fluid stripping elements may be formed on each respective support element and may be positioned on opposite sides of the respective support element.
According to another feature of the present invention, the fluid stripping elements are formed on the plurality of support elements to be symmetrical to a radial plane extending through a central axis of the respective support element and perpendicular to an axis of rotation for the deflection adjustment roll.
According to a still further feature of the present invention, the plurality of fluid stripping elements are one of at least partially located and formed to be active only when the plurality of support elements and plurality of fluid stripping elements are arranged in an upper half of the roll jacket, and to remain inactive when the plurality of support elements and the plurality of fluid stripping elements are arranged in a bottom half of the roll jacket. Further, when the plurality of fluid stripping elements are active, the deflection adjustment roll is positioned as a bottom roll and when the plurality of stripping elements remain inactive, the deflection adjustment roll is positioned as a top roll.
According to still another feature of the present invention, scraper elements may be arranged along the axial length of and adjacent to the inner surface of the roll jacket. The arrangement of scraper elements may include spaces corresponding to the plurality of support elements to strip the fluid flowing between the plurality of support elements from the inner surface of the roll jacket at least when the plurality of fluid stripping elements are inactive. An axial length of the scraper elements may be at least equal to the predetermined spacing between the plurality of support elements, and, alternatively, may be greater than the predetermined spacing between the plurality of support elements.
According to a further feature of the present invention, at least one of the scraper elements may be formed to produce a wedge gap between the inner surface of the roll jacket and the at least one scraper element. The at least one scraper element may be active only when the roll jacket rotates in the opposite direction and the at least one scraper element may permit fluid to pass when the roll jacket rotates in the one direction due to a hydrodynamic effect produced by the wedge gap.
According to another feature of the present invention, at least one of the scraper elements may be pressed against the inner surface of the roll jacket by a compression spring supported on the support member.
According to a further feature of the present invention, the deflection adjustment roll may also include at least one fluid recess, for a gravity-supported fluid discharge, associated with at least one of the plurality of fluid stripping elements and the scraper elements. Further, the at least one fluid recess may be formed between two strips located on top of the support member to collect fluid stripped by the at least one of the plurality of fluid stripping elements and scraper elements.
According to yet another feature of the present invention, the deflection adjustment roll may also include at least one air deflection plate, preceding at least one of the plurality of fluid stripping elements and the scraper elements, positioned, with respect to the inner surface of the roll jacket, to form a gap of predetermined size. The predetermined size may be sufficient to allow fluid entrained by the roll jacket and a small amount of border air to pass through the gap. Further, the predetermined size of the gap may be less than approximately 5 mm.
According to another feature of the present invention, the operating fluid may include a lubricant.
According to yet another feature of the present invention, the deflection adjustment roll may also include a fluid cushion formed between the support elements and the supporting member.
The present invention may be directed to a deflection adjustment roll that includes a roll jacket having an inner surface and being rotatable around a longitudinal axis, support elements positioned adjacent the inner surface of the roll jacket, and flow channel spaces formed between the support elements. The support elements and the flow channel spaces may be arranged along a length of the roll jacket. The deflection adjustment roll may also include a fluid stripping device coupled to the support elements and arranged to form fluid rings by removing operating fluid from the inner surface when the roll jacket rotates in a first direction and to form fluid rings by substantially deflecting the operating fluid on the inner surface when the roll jacket rotates in a second direction that is opposite the first direction.
According to another feature of the present invention, the support elements may include rounded elements and the fluid stripping device may include fluid stripping elements radially extending from the rounded elements. The fluid stripping elements may include an active side for removing operating fluid and an inactive side for substantially deflecting operating fluid.
According to still another feature of the present invention, the roll jacket may also include an upper portion and a lower portion. When the fluid stripping device is positioned in the upper portion of the roll jacket, the roll jacket may rotate in the first direction. Alternatively, when the fluid stripping device is positioned in the lower portion of the roll jacket, the roll jacket may rotate in the second direction.
According to a further feature of the present invention, scraper elements may be positioned adjacent the inner surface and opposite the support elements, and may be arranged along the length of the roll jacket to be radially opposite the flow channel spaces formed between the support elements.
According to still another feature of the present invention, the scraper elements may be arranged to remove operating fluid from the inner surface when the roll jacket rotates in the second direction. Alternatively, the scraper elements may be arranged to allow operating fluid to remain on the inner surface when the roll jacket rotates in the first direction.
According to a still further feature of the present invention, the scraper elements may include a beveled portion arranged to form a wedge gap between the inner surface and the beveled portion. Further, the scraper elements may include a removal portion, opposite the beveled portion, to remove operating fluid from the inner surface.
According to another feature of the present invention, the scraper elements may include a length greater than or equal to the flow channel spaces.
According to still another feature of the present invention, the deflection adjustment roll may also include a first fluid recess that may receive the operating fluid removed by the fluid stripping device and a second fluid recess that may receive the operating fluid removed by the scraper elements.
According to a still further feature of the present invention, the support elements may be held against the inner surface via a pressure fluid and the scraper elements may be held against the inner surface via a spring force.
According to yet another feature of the present invention, the support elements may include at least one of hydrostatic and hydrodynamic support elements.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of preferred embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:
FIG. 1 illustrates a simplified schematic cross-section of a deflection adjustment roll utilized as a bottom roll;
FIG. 2 illustrates a simplified schematic cross-section of a deflection adjustment roll utilized as a top roll;
FIG. 3 illustrates an enlarged top view of a support element of the deflection adjustment roll according to the present invention;
FIG. 4 illustrates a top view of an inner surface of the roll jacket of the deflection adjustment roll depicted in FIG. 1 which is depicted as unwound over an arc of more than 360°;
FIG. 5 illustrates a simplified schematic cross-section of an alternative embodiment of a deflection adjustment roll utilized as a top roll; and
FIG. 6 illustrates a top view of the support element of the deflection adjustment roll depicted in FIG. 5 having a preceding air deflection plate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The particulars shown herein are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for the fundamental understanding of the invention, the description taken with the drawing figures making apparent to those skilled in the art how the invention may be embodied in practice.
In a schematic cross-sectional representation, FIG. 1 illustrates a deflection adjustment roll according to the present invention. The deflection adjustment roll may include a rotating roll jacket 1, a support member or yoke 2 axially passing through roll jacket 1, and a plurality of hydrostatic and/or hydrodynamic support elements 3 that support roll jacket 1 on support member 2. The plurality of support elements 3 may be located next to each other along an axial direction of the roll jacket, and the support elements may be positioned to have a space, e.g., a distance a, between adjacent support elements. To exert a predetermined radial pressure against an interior surface of roll jacket 1, a fluid cushion may be formed between support member 2 and support elements 3. Further, the radial pressure exerted by the support elements against the interior surface of the roll jacket may also be exerted against a counter roll 22 so as to form a nip.
Support elements 3 may be formed, e.g., as piston-shaped elements and may be sealingly inserted into pressure chambers 10 formed in support member 2. A supply line 11 may be provided in support member 2 to provide pressure fluid to pressure chamber 10, and the pressure fluid may be utilized to adjustably press support elements 3 against the inner surface of roll jacket 1.
Each support elements 3 may have an end slip surface 14 for contacting a portion of roll jacket 1. Hydraulic pressure pockets 12 may be formed on end slip surfaces 14 and may communicate with a respective pressure chamber 10 to receive a supply of pressure fluid.
FIGS. 3 and 4 illustrate that support elements 3 may be formed as rounded elements and that two fluid stripping elements 4 that may be located on a round outer circumference of each support element 3. Fluid stripping elements 4 associated with each support element 3 may be symmetrical to a central axis of the respective support element 3, and each central axis of respective support elements 3 may extend perpendicular to a roll axis X (see FIG. 1). Fluid stripping elements 4 may each laterally protrude from support elements 3 and may extend into flow channels formed between adjacent support elements 3 to deliberately strip operating fluid circulating in the flow channels, i.e., around the support elements 3, from the inner surface of roll jacket 1. However, in accordance with the present invention, fluid stripping elements 4 may be formed such that they are only active when roll jacket 1 rotates in one particular direction and they remain substantially inactive when roll jacket 1 rotates in an opposite direction.
Accordingly, fluid stripping elements 4 may be formed, e.g., as blade-shaped elements and may respectively substantially radially protrude or extend from support elements 3. When active, fluid stripping elements 4 may also be positioned on an upstream region of support elements 3 with respect to a roll rotation direction R, i.e, a region oriented toward a fluid flow F, and may be directed counter to fluid flow F entrained by roll jacket 1, e.g., as indicated in FIG. 3.
However, if fluid flow F is reversed, i.e., the roll rotation direction is reversed, then support elements 3 will likewise be flowed against in the opposite direction. Accordingly, fluid stripping elements 4 may be positioned on a downstream region of the support elements 3, i.e., a region remote from circulating fluid F, and may be directed in the flow direction of fluid F, as shown in FIG. 4. In this manner, fluid stripping elements 4 offer only a slight flow resistance and, therefore, are considered substantially inactive.
To maintain as low a flow resistance as possible, and to reinforce the relatively narrow fluid stripping elements 4, the tips of the fluid stripping elements may each be coupled to support element 3 by a reinforcing strut 23 extending substantially parallel to fluid flow direction F, and which may connect the tip of fluid stripping element 4 to a substantially tangential extension from the outer circumference of support element 3.
The deflection adjustment roll illustrated in FIG. 1 is utilized as a bottom roll. Accordingly, fluid stripping elements 4 may be directed counter to the fluid F entrained by roll jacket 1, or roll rotation direction R. Therefore, fluid stripping elements are active to wipe fluid F circulating around support elements 3 from the inner surface of roll jacket 1. The stripped fluid F may be collected into a fluid recess 7 coupled to a side portion of support member 2. The stripped fluid may then be conveyed out of the roll through an outlet line 8 coupled between fluid recess 7 and a central discharge line 9. As shown in the Figure, central discharge line 9 may be positioned lower than fluid recess 7 so that the stripped fluid may be discharged solely due to hydrostatic pressure or gravity. Thus, the present invention does not require an aspiration device for removing the fluid stripped by the fluid stripping elements 4.
On an underside of support member 2, i.e., the side opposite support elements 3, a plurality of scraper elements 5 may be provided. Scraper elements 5 may be arranged over an axial length of roll jacket 1. As is more clearly illustrated in FIG. 4, which depicts the deflection adjustment roll as unwound over an arc A of more than 360° to show the spaced relationship and relative arrangement between support elements 3 and scraper elements 5, scraper elements 5 may be positioned relative to spaces "a" formed between adjacent support elements 3 so as to strip the fluid, flowing between, and channeled by, support elements 3, from the inner circumference of roll jacket 1.
Scraper elements 5 may have an axial length 1 and may be arranged to be offset relative to spacing a between support elements 3. For example, scraper elements 5 may be offset from support elements 3 by a half spacing T of the support element arrangement, i.e., scraper elements 5 may be positioned adjacent a circumferential portion of the roll jacket between adjacent support elements 3. Further, axial length 1 of scraper elements 5 may be slightly larger than distance a between adjacent support elements 3. In this manner, scraper elements 5 may be utilized to remove discrete fluid rings from an entire width of the inner circumference of roll jacket 1. The discrete fluid rings may be formed from the fluid entrained on the interior surface of roll jacket 1 that flows around support elements 3 (as shown by the arrows, and the discrete fluid rings may become somewhat wider after passing through the flow channels formed between the support elements 3.
Scraper elements 5 may be formed, e.g., like fluid stripping elements 4, so that they are only active in one rotational direction of roll jacket 1, e.g., when fluid stripping elements 4 are inactive. In this arrangement, when stripping elements are inactive, scraper elements 5 may be active so as to strip the fluid rings formed between the support elements 3 from the inner surface of roll jacket 1.
In the embodiment shown, the scraper element 5 may be pressed against the inner surface of roll jacket 1 by a spring force. Thus, scraper element 5, which may be formed, e.g., as blade-like, may be coupled, e.g., to a tappet 15. In this manner, scraper element 5 may pivot around an axis B perpendicular to roll axis X, and tappet 15 may be guided to move radially toward roll jacket 1 in a recess 16 provided in support member 2. A compression spring 6 may be inserted into recess 16 to provide a desired spring force to scraper element 5 against the inner surface of roll jacket 1.
Each scraper element 5 may be provided with an oblique face 17 oriented toward the inner surface of roll jacket 1 to produce a wedge gap between the inner circumference of roll jacket 1 and the respective scraper element 5 held against it. Accordingly, scraper elements 5 may only be active when roll jacket 1 is rotated in a direction that the fluid is directed to the non-wedged side of scraper element 5, i.e., opposite direction R shown in FIG. 1. However, when roll jacket 1 is rotated in direction R, as shown in FIG. 1, the hydrodynamic effect produced by the wedge gap permits fluid F to pass.
In the embodiment depicted in FIG. 1, the deflection adjustment roll is utilized as a bottom roll of a press device, in which roll jacket 1 is rotated in a direction R. As noted above, fluid stripping elements 4, provided on support elements 3, are active so as to strip the fluid F circulating around support elements 3 from the inner surface of roll jacket 1. At the same time, scraper elements 5 are inactive and, thus, allow fluid F to pass through due to the hydrodynamic effect produced by the wedge gap between oblique face 17 and roll jacket 1.
If the deflection adjustment roll, as depicted in FIG. 2, is utilized as a top roll, then roll jacket is rotated in a direction R', which is opposite direction R from FIG. 1. In this arrangement, fluid stripping elements 4 are inactive and, thus, extend substantially in the flow direction of fluid F. Fluid F contacts support element 3 at the end opposite fluid stripping elements so that the fluid is hardly stripped from roll jacket 1, rather fluid F is guided around support elements 3 to form the discrete fluid rings as fluid F is transported through the flow channels between adjacent support elements 3, as shown in FIG. 4. However, scraper elements 5 are positioned in their active position so as to strip the discrete fluid rings formed through the flow channels between support elements 3 from roll jacket 1.
Further, a fluid recess 7' may be associated with scraper elements 5 to collect the stripped fluid. Fluid recess 7' may be coupled to an outlet line 8 that feeds or guides the stripped fluid from fluid recess 7' to central discharge line 9. As noted above, with respect to fluid recess 7', central discharge line 9 may be positioned lower than fluid recess 7' so that the stripped fluid may be discharged solely due to hydrostatic pressure or gravity. Thus, the present invention also does not require an aspiration device for removing the fluid stripped by scraper device 5.
According to an alternative embodiment of the present invention illustrated in FIGS. 5 and 6, an air deflection plates 20 may be attached to support elements 3 to precede the fluid stripping elements 4 and/or the doctor elements 5. Air deflection plates 20 are positioned relative to the inner circumference of roll jacket 1 to form a gap of a predetermined size. The size of the gap may be set to enable the operating fluid F entrained by roll jacket 1 to flow unobstructed through the gap and to deflect most of the border air entrained by the fluid F. Thus, a small amount of the border air may be permitted to pass through the gap. In this manner, the fluid stripped by fluid stripping elements 4 or scraper elements 5 may flow away smoothly. The gap distance between air deflection plate 20 and the inner circumference of roll jacket 1 may be, e.g., less than 5 mm.
In the alternative embodiment illustrated in FIG. 5, fluid recess 7 may alternatively be formed between two strips 21 located on the top of support member 2 to collect fluid stripped by fluid stripping elements 4 or by doctor elements 5, whichever elements are active in the arrangement, i.e., located on top of support member 2. Fluid recess 7 may communicate with central discharge conduit 9 through a drop line 24 in order to discharge fluid collected in fluid recess 7 that has been stripped from the roll.
It is noted that the foregoing examples have been provided merely for the purpose of a explanation and are in no way to be construed as limiting of the present invention. While the invention has been described with reference to a preferred embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview ofthe appended claims, as presently stated and as amended, without departing from the scope and spirit of the invention in its aspects. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein; rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
Reference Numeral List
1 roll jacket
2 support member
3 support element
4 fluid stripping element
5 scraper element
6 compression spring
7 fluid recess
7' fluid recess
8 outlet line
9 central discharge line
10 pressure chamber
11 supply line
12 pressure pocket
13 line
14 slip surface
15 tappet
16 recess
17 oblique face
18 fluid recess
19 channel
20 air deflection plate
21 strips
22 counter roll
23 strut
24 drop line
a distance between support elements
l length of scraper elements
A unwound portion of roll showing an arc of more than 360°
B axis
F fluid
R rotation direction
R' rotation direction (opposite R)
T spacing
X roll axis | Deflection adjustment roll that includes a rotating roll jacket, a support member axially extending through the roll jacket, a plurality of at least one of hydrostatic and hydrodynamic support elements located next to one another with a predetermined spacing in an axial direction of the roll jacket to support the roll jacket on the support member, and a fluid removal device that removes operating fluid collected on an inner surface of the roll jacket during operation and that forms a fluid ring that circulates around the plurality support elements on the inner surface of the roll jacket. The fluid removal device may include a plurality of fluid stripping elements formed on the plurality of support elements that laterally protrude from each support element in a direction of a neighboring support element to strip the fluid circulating around the plurality of support elements from the roll jacket in the flow channels formed between the support elements. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates, in general, to a modular column system constructed by stacking at least one precast unit between a foundation section and a coping section, as well as a method of constructing the same, in which the precast unit makes use of an internally confined hollow column unit fabricated in advance, and in which a joint section between the precast units is firmly formed. As a result, the modular column system realizes a short construction period and economy because reinforcement bars and forms are not used, and also realizes high resistance to bending moment and a reduction in cross section and self-weight of the precast unit, so that the modular column system enables easier and more economical assembly, and prevents brittle fracture of the joint section between the precast units.
[0003] 2. Description of the Related Art
[0004] Generally, piers constructed in bridge work are cast-in-place concrete structures, in which, after foundation pit excavation work is carried out at the site, concrete is poured into formwork, in which reinforcement bars are arranged, and is cured for a predetermined period of time, and thereby a foundation section is formed.
[0005] After the foundation section is cured, the reinforcement bars and forms are arranged on the cured foundation section, and the concrete is poured into and cured in the formwork to form a pier. An upper portion of the pier, i.e. a coping section supporting a bridge deck, is formed by pouring concrete in a primary or secondary process after the forms are arranged in the state in which a staging is supported. Thereby, the pier is finished.
[0006] For this reason, a long construction period and great expense are required for the work of setting up the formwork and dismantling the formwork after curing the concrete. Further, problems with the pier can occur depending on the construction location. For example, in the case of constructing an elevated roadway, the pier creates a traffic jam around the construction site. Further, in the situation where the work environment is unfavorable, as in underwater work, the construction and management of the pier are difficult, and the possibility of faulty construction is increased.
[0007] In consideration of these aspects, piers have been constructed at sites in a method of constructing the foundation section including the foundation pit excavation under the ground, and then fabricating and assembling the pier as a unit structure.
[0008] To realize the advantages of construction of the modular pier, because a structure fabricated in a precast way in respective units, namely precast units, is fabricated in a factory, it is advantageous to control the quality of the concrete. Further, because the precast units are continuously fabricated, it is advantageous to manage manpower and the forms. In addition, because the precast units can be fabricated together with the construction of the foundation section, it is possible to reduce the construction period in comparison with the cast-in-place method.
[0009] In this manner, the modular pier constructed using the precast unit is disclosed in Korean Patent No. 10-99113 (titled “Modular Pier and Column Structure and Method of Constructing the Same”).
[0010] In the document, a plurality of precast units having a cross section of a spherical shape, a circular shape, or an oval shape is fabricated according to the height of a pier. Among the precast units, an upper precast unit has a convex shape at a lower end thereof, whereas a lower precast unit corresponding to the upper precast unit has a concave shape at an upper end thereof. Then, the upper and lower precast units are assembled. The convex and concave portions are provided with shear keys that are adapted to transmit compressive force, tensile force, axial force, and shear force when a bending moment is applied to the upper precast unit at five different positions. The shear keys are assembled in a construction method of injecting grout into shear key recesses of the middle thereof through an injection hole from the outside.
[0011] The above-described construction of the modular pier is characterized by directly assembling and constructing the pier structure as a unit structure at a site, and by the unit stably withstanding the fractional force transmitted thereto via the shear keys, installed in different directions, in conjunction with the injection of the grout.
[0012] However, when constructing this pier, it is difficult to set up the formwork for fabricating units having convex and concave shapes. Practically, due to its self-weight, the precast unit made of concrete has nothing but to be lifted by a crane, so that, when constructing a high pier, the number of precast units to be fabricated is excessively increased.
[0013] Meanwhile, the pier of the bridge serves to accept the load of its upper structure as the force to transmit it in a downward direction, and acts as a main member for resisting transverse loads, such as that of an earthquake. Hence, the pier should be designed such that it can resist vertical loading, transverse loading, bending moment, and so forth.
[0014] In consideration thereof, the design of the pier is based on the concept of a plastic hinge enabling core concrete to resist great compressive deformation and thus have the capability to dissipate energy. This means that the pier is endowed with ductile capability capable of causing plastic deformation against repeated load without remarkable reduction of stress resistance or rigidity.
[0015] The response modification factor taken into consideration in an earthquake-proof design is greatly influenced by this ductile capability. In the bridge, the ductile capability of the pier accounts for most of the ductile capability of the entire bridge.
[0016] Currently, the design criteria of roadway and railway bridges prescribe a transverse reinforcement ratio in order to secure the ductile capability of the plastic hinge section of the pier with respect to the earthquake and the transverse load. A reinforced concrete pier having a solid cross section is widely constructed on the basis of the transverse reinforcement ratio, and has good load supporting capacity.
[0017] However, the solid cross-section reinforced concrete pier has various disadvantages in that it is difficult to apply to a place where the foundation section encounters a structural problem due to the self-weight thereof, that it is economically unfavorable due to the increase in concrete material cost, and in that it encounters a chance of cracks occurring due to the generation of the heat of hydration when concrete is poured.
[0018] For this reason, attention is paid to a steel pier having advantages of good ductile capacity and a reduced construction period in spite of a certain disadvantage with respect to construction expenses.
[0019] However, the steel pier generally has a relatively greater width over the thickness of a deck constituting the pier, and thus has a problem in that it is vulnerable to local buckling when earthquakes occur.
[0020] Conventionally, in order to address this problem, a concrete filled steel tube (CFT) is used. CFT refers to a structure in which a steel tube having a circular or angular cross section is filled with concrete. Because the concrete is confined in the steel tube, CFT has advantages in that it is excellent in preventing the local buckling, has good ductile capability, and is reduced in cross section and self-weight due to an increase in resistance to the bending moment compared to the existing concrete pier.
[0021] However, CFT has a problem in that the material expense thereof is very high. Further, CFT still has a problem in that, when constructed as a high pier, it is increased in cross section and self-weight and thus is unsuitable for on-site conditions having restrictions on the ratio of width to thickness. In addition, CFT encounters a problem of maintenance for preventing corrosion thereof in on-site conditions, in which the corrosion becomes an issue, as in the underwater pier.
[0022] Further, in the case in which the pier of the bridge or the column of a building has a structural problem due to the excessive self-weight of concrete, or the material expense of the concrete is relatively high, a pier or a column having a hollow cross section is used, instead of one having a solid cross section.
[0023] Such a hollow cross-section pier or column is estimated to have high applicability because the resistance to the bending moment is not dynamically weaker compared to a usual pier or column.
[0024] Especially, as earthquake-proof design is currently becoming a hot issue, there is a necessity to design a pier or column capable of withstanding a greater bending moment, and furthermore, transverse displacement is required. Thus, when designing a pier or column capable of withstanding a great bending moment, a hollow cross-section pier or column, the self-weight of which is reduced because the inside thereof is hollow, can be more favorable according to the circumstances.
[0025] However, the ductile capacity of the hollow cross-section pier or column is doubtful, because it is difficult to expect a concrete confining effect therefrom. In other words, due to brittle fracture behavior caused in the inside of the hollow cross section because there is no concrete confining effect, the pier or column having a hollow cross-section evidences poor ductile capability in practice.
[0026] Nevertheless, in the case of modular piers proposed to date, no special study has been made of excessive self-weight in the case of using concrete for the precast unit, high material expense in the case of using CFT as a material for replacing concrete, whether to introduce the hollow cross section as an approach to resolve the increase in cross section and self-weight when constructing a high pier, the brittle fracture of the hollow cross section in the case of using the hollow cross section, and maintenance in the case of using CFT for, for example, an underwater pier.
SUMMARY OF THE INVENTION
[0027] Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an object of the present invention is to provide a modular column system using at least one internally confined hollow column unit, in which the internally confined hollow column unit includes an outer pipe section formed of steel or fiber reinforced plastic (FRP), a concrete section filled with concrete and forming a hollow section inside the outer pipe section, and an inner pipe section installed in the hollow section of the concrete section and formed of steel or FRP, which confines the concrete section, thereby providing easy assembly of the units as well as economical construction due to the advantages derived from construction using a general modular column system, due to the hollow section, and due to a reduction in self-weight caused by reduction of a cross section, and improving corrosion resistance by means of the inner and outer pipe sections formed of FRP in the case of, for example, an underwater pier.
[0028] In order to achieve the above object, according to one aspect of the present invention, there is provided a modular column system using at least one internally confined hollow column unit. The modular column system includes at least one precast unit installed between a foundation section and a coping section, and means for fastening the precast unit to the foundation section, fastening the precast units to each other, and fastening the coping section to the precast unit. The precast unit is an internally confined hollow column unit which includes an outer pipe section formed of steel or fiber reinforced plastic (FRP), a concrete section filled with concrete and forming a hollow section inside the outer pipe section, and an inner pipe section installed in the hollow section of the concrete section and formed of steel or FRP confining the concrete section.
[0029] Therefore, the modular column system of the present invention is constructed in a manner such that the internally confined hollow column unit is attached to the upper portion of the foundation section by means of the fastening means, such that the internally confined hollow column units are stacked on and attached to the attached hollow column unit up to the designed height of the modular column system, and such that the coping section is attached to an upper portion of the uppermost one of the internally confined hollow column units.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:
[0031] FIG. 1 is a perspective view illustrating an internally confined hollow column unit in a modular column system using at least one internally confined hollow column unit in accordance with the present invention;
[0032] FIG. 2 is a partial cross sectional view illustrating an internally confined hollow column unit as a component of the present invention, wherein an inner pipe section of the internally confined hollow column unit is formed as a cylindrical pipe;
[0033] FIG. 3 is a partial cross sectional view illustrating an internally confined hollow column unit as a component of the present invention, wherein an inner pipe section of the internally confined hollow column unit is formed as a corrugated pipe;
[0034] FIG. 4 is a perspective view illustrating a shear connector that is additionally installed to an internally confined hollow column unit as a component of the present invention;
[0035] FIG. 5 is a cutaway view illustrating an internally confined hollow column unit as a component of the present invention, wherein shear connectors are attached to inner and outer pipe sections of the internally confined hollow column unit;
[0036] FIG. 6 is a side cross sectional view illustrating the state in which internally confined hollow column units are stacked between a foundation section and a coping section, and are attached to each other at joint sections therebetween by fastening means in accordance with the present invention;
[0037] FIG. 7 is an exploded perspective view illustrating the state in which internally confined hollow column units are stacked between a foundation section and a coping section in accordance with the present invention;
[0038] FIG. 8 is a perspective view illustrating a bar-like member that includes a body section and a head section in accordance with an embodiment of the present invention;
[0039] FIG. 9 is an exploded perspective view illustrating the state in which a foundation section and a lowermost internally confined hollow column unit, two adjacent internally confined hollow column units, an uppermost internally confined hollow column unit, and a coping section are fastened by fastening means in accordance with an embodiment of the present invention;
[0040] FIG. 10 is an exploded perspective view illustrating the state in which a common joint section between internally confined hollow column units is attached by supports in accordance with the present invention;
[0041] FIG. 11 schematically illustrates a process of constructing a modular column system using at least one internally confined hollow column unit in accordance with the present invention; and
[0042] FIG. 12 is a flowchart illustrating a method of constructing a modular column system using at least one internally confined hollow column unit in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Reference will now be made in greater detail to an exemplary embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts.
[0044] As illustrated in FIG. 1 , an inner pipe section 13 is installed in the hollow section 14 of a concrete section 12 , and thus it confines the concrete section 12 . Thus, the concrete section 12 is under a triaxial compression load. Thereby, when a precast unit is fabricated, the hollow section 14 of the concrete section 12 is formed so as to reduce the self-weight of the precast unit to facilitate assembly, thereby preventing incidental brittle fracture in the cross section of the hollow section 14 of the concrete section 12 . Further, the inner pipe section 13 is inserted to reinforce the resistance to bending moment as well as to reduce the cross section and self-weight of the precast unit, and thus an internally confined hollow column unit 10 is preferably used as the precast unit for the assembly of a pier.
[0045] When constructed for a general structure, the inner pipe section 13 and an outer pipe section 11 are preferably made of steel, thereby securing the resistance to bending moment.
[0046] However, when being constructed for use in a corrosive environment, such as for an underwater pier, the inner and outer pipe sections 13 and 11 can be made of fiber reinforced plastic (FRP) having corrosion resistance and ductility. More preferably, the FRP is selected from materials suitable for the conditions of on-site construction, for instance FRPs to which reinforcing materials have been added, such as carbon FRP (CFRP), aramid FRP (AFRP), glass FRP (GFRP), and so on. Further, the use of such an FRP incidentally reduces the self-weight of the structure, thereby serving to make assembly easy.
[0047] As illustrated in FIG. 1 , the diameter D 1 of the hollow section 14 can be adjusted in a factory so as to meet the conditions of on-site construction in consideration of self-weight, costs of concrete materials, etc. at the time of assembly.
[0048] The hollow section 14 is formed so as to run through the concrete section 12 . Thus, as illustrated in FIG. 2 , in the case in which the inner pipe section 13 is formed as a cylindrical pipe 13 a , the hollow section 14 has the shape of a cylindrical column, thus being integrally formed with the inner pipe 13 a . As illustrated in FIG. 3 , in the case in which the inner pipe section 13 is formed as a corrugated pipe 13 b , the hollow section 14 has the shape of a cylindrical corrugated column, and is thus integrally formed with the corrugated pipe 13 b.
[0049] As illustrated in FIGS. 2 and 3 , the inner pipe section 13 can employ the cylindrical pipe 13 a having smooth surfaces, or a corrugated pipe 13 b alternating convexity with concavity.
[0050] In the case of using the cylindrical pipe 13 a , there is an advantage in that it can exert resistance to axial compressive force and bending moment. In the case of using the corrugated pipe 13 b , it has a good effect of confining the concrete section 12 , and thus is suitable for preventing local buckling of the inner pipe section 13 as well as increasing the ductility of the precast unit, so that it can be properly selected according to the conditions at a construction site.
[0051] As illustrated in FIG. 5 , the outer pipe section 11 is provided with a plurality of shear connectors 16 , which serve to secure unified behavior with the concrete section 12 , attached to the inner surface thereof, to which the concrete section 12 is attached.
[0052] Similarly, as illustrated in FIG. 5 , the inner pipe section 13 is also provided with a plurality of shear connectors 16 , which serve to secure unified behavior with the concrete section 12 , attached to the outer surface thereof, to which the concrete section 12 is attached.
[0053] The shear connectors 16 are formed of steel in the case in which the inner and outer pipe sections 13 and 11 are formed of steel. Thereby, the shear connectors 16 are preferably welded to the outer and inner surfaces of the inner and outer pipe sections 13 and 11 , to which the concrete section 12 is attached. At this time, a weld zone between the inner or outer pipe section 13 or 11 and each shear connector 16 is preferably prevented from brittle fracture by maintaining strength greater than that of each of the inner and outer pipe sections 13 and 11 and the shear connectors 16 .
[0054] Meanwhile, the shear connectors 16 are formed of FRP in the case in which the inner and outer pipe sections 13 and 11 are formed of FRP. Thereby, the shear connectors 16 are preferably bonded to the outer and inner surfaces of the inner and outer pipe sections 13 and 11 , to which the concrete section 12 is attached. At this time, the bonding zone between the inner or outer pipe section 13 or 11 and each shear connector 16 is preferably prevented from brittle fracture by maintaining strength greater than that of each of the inner and outer pipe sections 13 and 11 and the shear connectors 16 .
[0055] As illustrated in FIG. 4 , each shear connector 16 includes a stiffener portion 16 a that has plate shape and is attached in an axial direction of the unit and functions to resist the buckling of the unit, and a stud portion 16 b that is integrally formed with the stiffener portion 16 a , is attached in a plate shape in a radial direction of the unit, and secures unified behavior of the inner and outer pipe sections 13 and 11 with the concrete section 12 . Thereby, each shear connector 16 can be constructed to secure unified behavior of the inner and outer pipe sections 13 and 11 with the concrete section 12 , as well as exert a function of preventing the precast unit from buckling.
[0056] Meanwhile, as illustrated in FIGS. 6 and 7 , means for fastening a foundation section 20 and the uppermost one of the internally confined hollow column units 10 includes a plurality of foundation section anchoring holes 21 that are formed in the upper portion of the foundation section 20 , a plurality of lower anchoring holes 15 b that are formed in the lower portion of the concrete section 12 and are opposite the foundation section anchoring holes 21 , a plurality of bar-like members 40 that are inserted between the lower anchoring holes 15 b and the foundation section anchoring holes 21 , and grout 50 that fixes the bar-like members 40 .
[0057] Further, means for fastening a coping section 30 and the lowermost one of the internally confined hollow column units 10 includes a plurality of coping section anchoring holes 31 formed in the lower portion of the coping section 30 , a plurality of upper anchoring holes 15 a that are formed in the upper portion of the concrete section 12 and are opposite the coping section anchoring holes 31 , a plurality of bar-like members 40 that are inserted between the upper anchoring holes 15 a and the coping section anchoring holes 31 , and grout 50 that fixes the bar-like members 40 .
[0058] Also, means for fastening the two adjacent internally confined hollow column units 10 includes a plurality of upper anchoring holes 15 a that are formed in the upper portion of the lower one of the internally confined hollow column units 10 , a plurality of lower anchoring holes 15 b that are formed in the lower portion of the upper one of the internally confined hollow column units 10 and are opposite the upper anchoring holes 15 a , a plurality of bar-like members 40 that are inserted between the upper anchoring holes 15 a and the lower anchoring holes 15 b , and grout 50 that fixes the bar-like members 40 .
[0059] These fastening means are constructed to attach the lowermost one of the internally confined hollow column units 10 to the foundation section 20 , and between the two adjacent internally confined hollow column units 10 , and between the uppermost one of the internally confined hollow column units 10 and the coping section 30 by inserting the bar-like members 40 into the anchoring holes 15 a , 15 b , 21 and 31 , and then curing the grout 50 between the bar-like members 40 and the anchoring holes 15 a , 15 b , 21 and 31 .
[0060] In order to provide stronger attachment, as illustrated in FIG. 8 , the bar-like members 40 include a body section 41 and head sections 42 that are located at opposite ends of the body section 41 and are thicker than the body section 41 . Preferably, when the bar-like members 40 are inserted into the anchoring holes 15 a , 15 b , 21 and 31 , and then are attached by injecting of the grout 50 , each bar-like member 40 is more strongly attached due to the step in each head section 42 . Each bar-like member 40 is preferably made of a steel bar, etc, and the dimensions thereof, such as length, are adjusted according to the bending moment generated from the joint sections 80 of the internally confined hollow column units 10 .
[0061] The numbers of the bar-like members 40 and the anchoring holes 15 a , 15 b , 21 and 31 are preferably adjusted depending on the bending moment generated in the joint sections 80 of the internally confined hollow column units 10 .
[0062] The grout 50 is used not only for attaching the bar-like members 40 to the anchoring holes 15 a , 15 b , 21 and 31 , but also for preventing the bar-like members 40 from corroding in the case in which each bar-like member 40 is made of a mixture of a steel bar and cement paste or mortar. The grout 50 preferably has fluidity and expansibility suitable to compactly fill the anchoring holes 15 a , 15 b , 21 and 31 .
[0063] As illustrated in FIGS. 6 and 7 , the foundation section 20 is provided with a column unit insertion recess 22 into which the lowermost internally confined hollow column unit 10 is inserted. Thereby, the lowermost internally confined hollow column unit 10 can be firmed stacked on the foundation section 20 . The foundation section 20 can be formed in the shape of a circle, a tetragon or the like depending on the shape of the lowermost internally confined hollow column unit 10 .
[0064] According to one embodiment of the present invention, as illustrated in FIG. 9 , the means for fastening the foundation section 20 and the lowermost internally confined hollow column unit 10 includes a lower outer flange 62 a that is attached to the lower outer circumference of the outer pipe section 11 of the lowermost internally confined hollow column unit 10 and is provided with a plurality of lower outer fastening holes 63 a , and a plurality of fasteners 101 , such as bolts, that pass through the lower outer fastening holes 63 a , are inserted into a plurality of foundation section outer fastening holes 23 a at the upper portion of the foundation section 20 , and fasten the lower outer flange 62 a to the foundation section 20 .
[0065] A lower inner flange 62 b is attached to the lower inner circumference of the inner pipe section 13 of the lowermost internally confined hollow column unit 10 and is provided with a plurality of lower inner fastening holes 63 b . A plurality of fasteners 101 , such as bolts, passes through the lower inner fastening holes 63 b , is inserted into a plurality of foundation section inner fastening holes 23 b at the upper portion of the foundation section 20 , and fastens the lower inner flange 62 b to the foundation section 20 . Thereby, the means for fastening the foundation section 20 and the lowermost internally confined hollow column unit 10 preferably prevents brittleness of the joint section 80 between the foundation section 20 and the lowermost internally confined hollow column unit 10 .
[0066] As illustrated in FIG. 9 , the means for fastening the coping section 30 and the uppermost internally confined hollow column unit 10 includes an upper outer flange 60 a that is attached to the upper outer circumference of the outer pipe section 11 of the uppermost internally confined hollow column unit 10 and is provided with a plurality of upper outer fastening holes 61 a , and a plurality of fasteners 101 , such as bolts that pass through the upper outer fastening holes 61 a , are inserted into a plurality of coping section outer fastening holes 32 a at the lower portion of the coping section 30 , and fasten the upper outer flange 60 a to the coping section 30 .
[0067] An upper inner flange 60 b is attached to the upper inner circumference of the inner pipe section 13 of the uppermost internally confined hollow column unit 10 and is provided with a plurality of upper inner fastening holes 61 b . A plurality of fasteners 101 , such as bolts, passes through the upper inner fastening holes 61 b , is inserted into a plurality of coping section inner fastening holes 32 b at the lower portion of the coping section 30 , and fastens the upper inner flange 60 b to the coping section 30 . Thereby, the means for fastening the coping section 30 and the uppermost internally confined hollow column unit 10 preferably prevents brittleness of the joint section 80 between the coping section 30 and the uppermost internally confined hollow column unit 10 .
[0068] Further, the means for fastening two adjacent internally confined hollow column units 10 includes an upper outer flange 60 a that is attached to the upper outer circumference of the outer pipe section 11 of the lower internally confined hollow column unit 10 and is provided with a plurality of upper outer fastening holes 61 a , a lower outer flange 62 a that is attached to the lower outer circumference of the outer pipe section 11 of the upper internally confined hollow column unit 10 and is provided with a plurality of lower outer fastening holes 63 a opposite the plurality of upper outer fastening holes 61 a , and a plurality of fastener tools 100 , for example, bolts and nuts, that pass through the upper and lower outer fastening holes 61 a and 63 a and fasten the upper and lower outer flanges 60 a and 62 a to each other.
[0069] An upper inner flange 60 b is attached to the upper inner circumference of the inner pipe section 13 of the lower internally confined hollow column unit 10 , and is provided with a plurality of upper inner fastening holes 61 b . A lower inner flange 62 b is attached to the lower inner circumference of the inner pipe section 13 of the upper internally confined hollow column unit 10 , and is provided with a plurality of lower inner fastening holes 63 b opposite the plurality of upper inner fastening holes 61 b . A plurality of fastener tools 100 , for example bolts and nuts, passes through the upper and lower inner fastening holes 61 b and 63 b and fastens the upper and lower inner flanges 60 b and 62 b to each other. Thereby, the means for fastening two adjacent internally confined hollow column units 10 preferably prevents brittleness of the joint section 80 between the two adjacent internally confined hollow column units 10 .
[0070] The flanges 60 a , 60 b , 62 a and 62 b , which are attached to the upper and lower circumferences of the internally confined hollow column unit 10 , have an annular shape, such as a circular shape or a quadrilateral shape, which can be determined to correspond to the shape of the cross section of the internally confined hollow column unit 10 . The hollow inner diameter D 4 of each of the upper and lower outer flanges 60 a and 62 a is equal to the outer diameter D 2 of the outer pipe section 11 of the internally confined hollow column unit 10 . Thus, the upper and lower outer flanges 60 a and 62 a can be attached to the outer surfaces of the opposite ends of the outer pipe section 11 by means of welding. Alternatively, in the case in which the outer pipe section 11 is formed of plastic, such as FRP, the upper and lower outer flanges 60 a and 62 a may be attached to the outer surfaces of the opposite ends of the outer pipe section 11 by means of bonding.
[0071] The outer diameter D 5 of each of the upper and lower inner flanges 60 b and 62 b is equal to the inner diameter D 3 of the inner pipe section 13 of the internally confined hollow column unit 10 . Thus, the upper and lower inner flanges 60 b and 62 b can be attached to the inner surfaces of the opposite ends of the inner pipe section 13 by means of welding. Alternatively, in the case in which the inner pipe section 13 is formed of plastic, such as FRP, the upper and lower inner flanges 60 b and 62 b may be attached to the inner surfaces of the opposite ends of the inner pipe section 13 by means of bonding.
[0072] According to another embodiment of the present invention, as illustrated in FIG. 10 , the means for fastening two adjacent internally confined hollow column units 10 includes an outer support 70 a that is attached in a strip shape to the outer circumference of the joint section 80 between the upper and lower internally confined hollow column units 10 .
[0073] An inner support 70 b is attached in a strip shape to the inner circumference of the joint section 80 between the upper and lower internally confined hollow column units 10 . Thereby, the means for fastening two adjacent internally confined hollow column units 10 preferably prevents brittleness of the joint section 80 between the upper and lower hollow column units 10 .
[0074] The outer and inner supports 70 a and 70 b are attached to the outer and inner circumferences of the joint section 80 between the upper and lower hollow column units 10 by means of welding in the case in which the outer and inner pipe sections 11 and 13 are formed of steel, or by means of bonding in the case in which the outer and inner pipe sections 11 and 13 are formed of plastic such as FRP. Thereby, the outer and inner supports 70 a and 70 b prevent brittleness of the joint section 80 between the upper and lower hollow column units 10 .
[0075] As described above, when the adjacent hollow column units 10 are mutually attached using the flanges 60 a , 60 b , 62 a and 62 b or the supports 70 a and 70 b , they are first attached to each other by means of the bar-like members 40 inserted in the upper and lower anchoring holes 15 a and 15 b as well as the grout 50 , and then by means of either the fastener tools, such as bolts and nuts, fastened to the flanges thereof or the supports 70 a and 70 b attached to the joint section 80 . Thereby, the brittleness of the joint section 80 in the modular column system can be prevented.
[0076] Further, in the case in which the internally confined hollow column unit 10 is attached to either the upper portion of the foundation section 20 or the lower portion of the coping section 30 , they are first attached to each other by means of the bar-like members 40 inserted between the lower anchoring holes 15 b and the foundation section anchoring holes 21 and between the upper anchoring holes 15 a and the coping section anchoring holes 31 as well as the grout 50 , and then by means of the fasteners 101 , such as bolts, that are fastened either to the upper portion of the foundation section 20 through the lower outer and inner flanges 62 a and 62 b or the lower portion of the coping section 30 through the upper outer and inner flanges 60 a and 60 b . Thereby, the brittleness of the joint section 80 in the modular column system can be prevented.
[0077] Meanwhile, as illustrated in FIGS. 11 and 12 , a method of constructing the modular column system using at least one internally confined hollow column unit in accordance with the present invention includes a step S 1 of constructing the foundation section 20 with the plurality of foundation section anchoring holes 21 after pit excavation work.
[0078] In step S 1 of constructing the foundation section 20 , the column unit insertion recess 22 , into which the lowermost one of the internally confined hollow column units 10 is inserted, can be formed at the upper portion of the foundation section 20 .
[0079] The grout 50 is injected into the foundation section anchoring holes 21 (step S 2 ).
[0080] Before the grout 50 in the foundation section anchoring holes 21 is cured in step S 2 , the bar-like members 40 , which have been inserted into and attached in the lower anchoring holes 15 b of the lowermost internally confined hollow column unit 10 to be placed on the upper portion of the foundation section 20 , are inserted into the foundation section anchoring holes 21 , into which the grout 50 has been injected, and thus the lowermost internally confined hollow column unit 10 is attached to the foundation section (step S 3 ).
[0081] In the case of the bar-like members 40 inserted into the lower anchoring holes 15 b of the lowermost internally confined hollow column unit 10 , it does not matter that the bar-like members 40 are inserted into the lower anchoring holes 15 b at the site before injection of the grout 50 into the lower anchoring holes 15 b . However, in this case, the period for construction is delayed due to the time it takes to cure the grout, so that the internally confined hollow column unit 10 is preferably precast in a factory with the bar-like members 40 inserted into and attached in the lower anchoring holes 15 b in the interest of reducing the construction period as well as economy.
[0082] In step S 3 of attaching the lowermost internally confined hollow column unit to the foundation section, the lower outer flange 62 a having the plurality of lower outer fastening holes 63 a and the lower inner flange 62 b having the plurality of lower inner fastening holes 63 b are attached to the lower outer and inner circumferences, respectively, of the lowermost internally confined hollow column unit 10 , placed on the upper portion of the foundation section. Then, the fasteners 101 are fastened in the foundation section outer and inner fastening holes 23 a and 23 b of the upper portion of the foundation section 20 , thereby attaching the lower outer and inner flanges 62 a and 62 b to the foundation section 20 .
[0083] Then, the grout 50 is injected into the upper anchoring holes 15 a of the lowermost internally confined hollow column unit 10 , which has been placed on the upper portion of the foundation section 20 in step S 3 (step S 4 ).
[0084] Before the grout 50 in the upper anchoring holes 15 a is cured in step S 4 , the bar-like members 40 , which have been inserted into and attached in the lower anchoring holes 15 b of the internally confined hollow column unit 10 to be placed on the lowermost internally confined hollow column unit 10 on the foundation section 20 , are inserted into the upper anchoring holes 15 a of the lowermost internally confined hollow column unit 10 , into which the grout 50 has been injected, and thus the adjacent hollow column units 10 are attached to each other (step S 5 ).
[0085] According to one embodiment of the present invention, in step S 5 of attaching the internally confined hollow column units 10 to each other, the internally confined hollow column units 10 are each provided with the upper and lower outer flanges 60 a and 62 a and the upper and lower inner flanges 60 b and 62 b , and then are attached to each other using the fastener tools 100 .
[0086] Further, according to another embodiment of the present invention, in step S 5 of attaching the internally confined hollow column units 10 to each other, the joint section 80 between the internally confined hollow column units 10 is attached to the outer support 70 a on the outer circumference thereof and to the inner support 70 b on the inner circumference thereof, and thereby the internally confined hollow column units 10 are attached to each other.
[0087] The internally confined hollow column units 10 are stacked and attached up to the designed height of the modular column system by means of repetition of steps S 4 and S 5 (step S 6 ).
[0088] Then, the grout 50 is injected into the upper anchoring holes 15 a of the uppermost internally confined hollow column unit 10 , which has been placed on the upper portion of the foundation section 20 in step S 6 (step S 7 ).
[0089] Before the grout 50 in the upper anchoring holes 15 a is cured in step S 7 , the bar-like members 40 , which have been inserted into and attached in the coping section anchoring holes 31 of the lower portion of the coping section 30 , are inserted into the upper anchoring holes 15 a , into which the grout 50 has been injected, and thus the uppermost internally confined hollow column unit 10 is attached to the coping section (step S 8 ).
[0090] In step S 8 of attaching the coping section 30 to the upper portion of the uppermost internally confined hollow column unit 10 , the upper outer flange 60 a and the upper inner flange 60 b are attached to the upper outer and inner circumferences, respectively, of the uppermost internally confined hollow column unit 10 , placed under the coping section 30 . Then, the fasteners 101 are fastened in the coping section outer and inner fastening holes 32 a and 32 b of the lower portion of the coping section 30 , thereby attaching the upper outer and inner flanges 60 a and 60 b to the coping section 30 .
[0091] As apparent from the above description, the modular column system using at least one internally confined hollow column unit and the method of constructing the same in accordance with the present invention provide the following advantages.
[0092] First, the resistance to the bending moment is increased using the internally confined hollow column units, in which the concrete section is confined by the inner pipe section, and thus is under triaxial compression load. As a result, the internally confined hollow column units are each reduced in cross section and self-weight, and thus make assembly easy.
[0093] Second, the hollow sections of the internally confined hollow column units result in the use of less concrete, a reduction in the cross section of each of the internally confined hollow column units, elimination of the need for forms, elimination of the use of steel bars, and so on. As a result, the economically advantageous effect of reducing labor costs for installation can be obtained.
[0094] Third, the internally confined hollow column units are each provided with the inner and outer pipe section formed of plastic, such as FRP, such that they can be used in corrosive environments, such as in an underwater pier, and thus are advantageous for maintenance. In the case of using the FRP, the internally confined hollow column units can be reduced in self-weight.
[0095] Fourth, the brittle fracture of the joint sections between the internally confined hollow column units can be prevented by the strong attachment of the joint sections.
[0096] Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | A modular column system and a method of constructing the same are constructed by stacking at least one precast unit between a foundation section and a coping section. The precast unit makes use of an internally confined hollow column unit fabricated in advance, and joint sections between the precast units are firmly formed. Thereby, the modular column system can realize a short construction period and economy because reinforcement bars and forms are not used, as well as high resistance to bending moment and reduction in cross section and self-weight of the precast unit, and thus the modular column system can provide easier and more economical assembly, and prevent brittle fracture of the joint section between the precast units. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a rope system and more particularly, an endless rope which is arranged to travel through a machine while being tensioned in its longitudinal direction.
2. Description of the Related Art
In conventional rope systems, sometimes there is a danger that a rope gets stuck or that a rope is inadvertently wrapped around a drying cylinder or around a roll. This may result in serious damage to the equipment, e.g. to the rope tensioning device or to other elements of the rope system.
In the paper technology, in particular in paper or cardboard making machines or in paper or cardboard finishing machines, a rope system is often used for threading the paper or cardboard web into the machine (in particular into the drying section) when the machine is started up or after a web break. Basically, two (sometimes three) endless ropes are used which travel together along the web travel path through a drying section, a calendar section or a coating section. At the upstream end of a section, the two ropes form a rope nip. At this point, the ropes grip the beginning of an edge strip (a so-called “tail”) of the paper or cardboard web and transfer the edge strip through the section.
What is needed in the art is a rope system wherein the potential of damage to the equipment is eliminated or at least reduced.
SUMMARY OF THE INVENTION
The present invention provides a rope system and method for using a rope system that includes a measuring device for measuring the tension value in at least one endless rope. Preferably, the tension value is measured continuously during operation of the machine.
The measuring device is adapted to detect excessive tension, which is above the desired tension value normally maintained in the rope. Excessive tension may appear if the rope gets stuck or if other damage occurs to the rope system.
According to one embodiment of the invention, a rope cutter is provided for severing the endless rope if the rope suddenly is excessively tensioned. The rope cutter becomes immediately active when excessive tension is detected.
Generally, after severing the rope, the paper making machine is able to continue operating in the normal way because any danger of damage to the machine has been eliminated. Certainly, some loss arises from severing the rope. However, this loss is inconsequential in comparison to the damage that would occur to the mechanical equipment if the rope was not cut.
Preferably, the rope system of the present invention includes a rope tensioning device with a cylinder which is adapted to move at least one sheave, that is wrapped by the rope, for tensioning the rope. A selected pressure will be supplied to the cylinder which corresponds to the desired tension value. The measuring device is adapted to measure the prevailing pressure in the cylinder. The measuring device may be embodied as a pressure switch which creates a signal if the pressure in the cylinder exceeds the selected pressure. That signal will then be transmitted to the rope cutter.
In one embodiment of the invention, the rope cutter includes a cylinder for actuating the rope cutter. A control valve may be provided to control the cylinder such that the cylinder actuates the rope cutter when the signal exists. In a preferred embodiment of the invention, the control valve is controlled by a pressure fluid (e.g. compressed air) which is admitted to the control valve when the signal exists.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 shows a section of a rope system, namely a rope tensioning device including a rope cutter according to the invention; and
FIG. 2 is a view along arrow II of FIG. 1 .
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1, there is shown a rope tensioning device 8 of the rope system including two movable sheaves 11 and 12 which support rope 9 a , 9 and 9 b . As an example, rope 9 a is the incoming run and rope 9 b is the outgoing run of rope 9 . The arrangement is such that, where rope 9 a , 9 and 9 b wraps sheaves 11 and 12 , rope 9 a , 9 and 9 b form a single S (or an inverted S). Sheaves 11 and 12 are movable from an initial position, shown in full lines, away from each other, each by a distance L, into a final position as shown in dot-dash-lines, thereby extending rope 9 by a length of four times distance L.
In another embodiment of the invention, the tension device may include only one movable sheave.
Rope tensioning device 8 (FIGS. 1 and 2) includes a stationary frame 10 supporting two rodless pneumatic cylinders 14 and 15 . Each cylinder 14 and 15 having a movable piston (not shown) to which sheave support 13 is connected. Sheave supports 13 are adapted to support rotatable sheaves 11 and 12 (e.g. by antifriction bearings).
In yet another embodiment of the invention rope tensioning device 8 will be positioned in a paper-making machine in which rope 9 is used. In the paper-making machine, the tensioning device may be arranged horizontally (as shown in FIG. 1 ), vertically, upside down or in any other orientation. Two or more tensioning devices may be combined in order to tension a twin-rope-system or a three-rope-system. Usually, each rope forms an endless loop traveling at the operating speed of the paper-making machine.
At the infeed end of rope tensioning device 8 (close to the incoming run 9 a of rope 9 ), rope cutter 20 is mounted on frame 10 . Rope cutter 20 includes a pivotable knife 21 which is adapted to cooperate with stationary counter knife 22 . Knife 21 is pivotable around an axle having an axis 23 . Also, knife 21 is coupled to piston 24 of a double acting pneumatic cylinder 25 which is coupled to frame 10 .
A two position control valve 30 connects pressure source 31 via line 32 and either via line 26 to one side of cylinder 25 for moving (shown in the drawing) and holding knife 21 in its inoperative position as shown in FIG. 2, or via line 27 to the other side of cylinder 25 for actuating knife 21 .
If knife 21 is to be actuated, valve 30 is switched over, e.g. pneumatically, by supplying pressure from pressure source 31 via line 33 , auxiliary control valve 34 and line 35 to valve 30 . This occurs if a signal is transmitted from rope tension measuring device 36 via line 37 to auxiliary control valve 34 . As an alternative, the signal may be directly transmitted from measuring device 36 via line 38 to control valve 30 .
Measuring device 36 is adapted to measure the tension in rope 9 . Normally, the tension in rope 9 is held at a desired value, by maintaining a selected pressure, supplied from pressure source 19 , via line 18 to cylinder 15 .
If the tension in rope 9 increases to a predetermined excessive tension value (above the desired value), resulting in increased pressure in cylinder 15 and in line 18 , measuring device 36 creates the signal to be transmitted by line 37 . As an example, measuring device 36 is designed as a pressure switch pilot valve (sometimes called “sequence valve”) which connects line 18 to line 37 . If the pressure in line 18 exceeds a certain value which can be adjusted, e.g. by setting the force of a spring 39 , the signal is generated.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A rope system includes an endless rope, a measuring device and a rope cutter. The endless rope is configured to travel through a machine, while the endless rope is under tension. The measuring device is used to measure the tension in the endless rope. The rope cutter is positioned to sever the endless rope if the tension exceeds a predetermined value. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus where the wet of several different gas flows is carried out in at least three scrubbing towers, and the droplet separation of the scrubbed gases takes place in a uniform cyclon-type droplet separator, so that the obtained product is a pure, dropless gas.
2. Description of Related Art
Presently the tightened legislation in environmental protection sets higher and higher demands on the cleaning of exhaust gases. Above all this concerns industry and may become a threshold issue for many company, as for the continuation of production. This also means that more and more companies will invest in gas scrubbing, both in development and production as well as in new purchases.
In the majority of conventional practices, attention is paid to the scrubbing phase only, with the confidence that some separate, ready-made filter serves well enough as the droplet separator. This means that the scrubber units easily become bulky groups of miscellaneous constructions, if there are more gas lines than one. It is, however, pointed out that easy maintenance and effective droplet separation are in most cases almost as important as the scrubber unit itself.
An ideal solution for such cases is a combined scrubber and droplet separator unit, where the exhaust gases from different stages can be conducted separately and discharged directly into open air.
In principle, the scrubbing of gases can thus be divided into two stages, i.e. the scrubbing proper and the successive droplet separation. The scrubbing methods and requirements largerly define what kind of scrubber is best. The same applies to droplet separators.
A very popular principle is the venturi principle. In practice this includes two different types. One type uses a water spray to give strength and energy to the scrubbing, and at the same time the spray serves as a kind of blower, a suction fan. In the other type, the gas itself renders strength to the process, in which case the gas must be pressurized.
Both of the above mentioned scrubber types are described to a great detail in literature, for example in the following references: (1) H. Brauer, Y. B. G. Varma: Air Pollution Control Equipment, Springer-Verlag 1981, or (2) W. Strauss: Industrial Gas Cleaning, Pergamon Press 1975.
One problem when using venturi scrubbers, as well as with other scrubber types, is changing the capacity. The patent specification FR 2,452,311 introduces a system where a collar restricting the gas flow is formed in the venturi shaft by means of an annular water layer. By adjusting the thickness of the water layer, any changes in the capacity can be easily responded to.
Another, perhaps even more problematic situation is created when the capacity rises to a higher order. In that case the range of the water spray in relation to the gas flow is not sufficient, no matter which of the two venturi systems is employed. In order to solve this problem, for instance the reference (1), on pages 109 and 110, introduces applications with several venturis instead of only one.
Centrifugal force can also be made use of in gas scrubbers. A wet cyclone based on this idea is described for instance in the U.S. Pat. No. 2,696,275 and on the page 374 of reference (2), where a centrifugal wet scrubber and a turbulence phenomenon created by means of guiding vanes is introduced.
From the U.S. Pat. No. 3,456,928, there is known a scrubber based on a kind of a blower effect, where the gas flow is allowed to blow towards the surface of the water collected on the bottom of the scrubber.
Upwards rising gas to be cleaned can be put to contact with downwardly directed water sprays by using a cylindrical scrubbing vessel, as is described in the U.S. Pat. No. 3,773,472. The direction of the two flows can also be opposite. A similar type of scrubbing method, where the scrubbing cylinder is filled with filler particles, is described for instance on pages 122-123 and 129 of reference (1).
Different types of droplet separators are described for instance on pages 219-239 of reference (1). The main droplet separator types are based on the zig-zag principle, centrifugal principle or conventional filter principle.
According to the present invention, the gas or gases to be scrubbed are conducted into at least three vertical scrubbing tubes, and thereafter into a uniform droplet separator formed of several nested cylinders, where the gases are forced in a rotary motion and the pure and droplet-free gas is drained through a drain tube located in the middle of the scrubbing tubes. The essential novel features of the invention are apparent from the appended patent claims.
An advantage of several scrubbing tubes is that even with large gas volumes, the scrubbing process still remains well under control. In droplet separation, the uniform treatment of even large amounts of gases has not caused problems--on the contrary, from the point of view of building technique, it is simpler to construct a compact apparatus where all of the gas, even a large amount, is conducted to. Nowadays, owing to the said strict air-protective legislation, the tendency is to clean the gases of more and more components, and consequently the scrubber of the present invention with several scrubbing tubes is well suited to this purpose. At the droplet separation stage, solid particles have already been removed, and therefore it is even more recommendable to treat the gases flexibly together. Moreover, the apparatus is particularly suitable for treating emissions, because after cleaning, all of the gases can be discharged into open air.
Gases are conducted into the scrubbing tubes either separately, or after first combining them in the preliminary chamber and then distributing them into the tubes. The scrubbing tubes can be mutually similar or different, both in operation and size, depending on the scrubbing requirements--advantageously, however, they are similar. Because the tubes can differ from each other, it is possible to use the apparatus for treating emissions from different types of sources, and each emission type can be treated in a unit particularly designed for it. Thus the scrubbing tubes can be for instance a venturi scrubber, a centrifugal wet scrubber, a spray-type scrubber or a filler scrubber. The essential point is that the scrubbing tubes are located symmetrically with respect to each other. After the scrubbing process, the scrubbed gases are allowed to collide in the water gathered in the largest cylindrical vessel of the scrubber of the invention, which collision leads to the second stage of the scrubbing process.
The gases scrubbed in the scrubbing tubes are tangentially conducted, each along its specific conduit, to the next cylinder. Only in this cylinder, the gases are combined. The tangential path is arranged by means of auxiliary walls in the chamber and by possible blade extensions. This second largest cylinder begins, in the vertical direction, from the ceiling of the scrubbing chamber, and ends--as open--underneath the water level. Thus conditions for a simple and effective droplet separation are created; for the tangential feeding of gases secures the operation of centrifugal forces, so that the rotary gas flow is burst into the next inner cylinder through the annular opening located in between this inner cylinder, its bottom part and the water surface. From this inner cylinder, the gas is discharged, through the smallest cylinder, and according to a normal cyclone effect, upwards droplet-free.
The scrubbed, droplet-free yet saturated gas can be conducted directly to the open air or, if conditions particularly require, through a heat exchanger formed by the hot gases entering the scrubber for cleaning, in which case the temperature of the gas to be drained rises to a level where water is not condensed on the possibly cold walls of the drain pipe. This fact is observed particularly when scrubbing in unheated facilities.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in more detail with reference to the appended drawings, where
FIG. 1 illustrates the basic principle of a scrubber of the invention, comprising four different venturi scrubber units,
FIG. 2 is a lengthwise cross-section of the bottom part of the scrubber of FIG. 1,
FIGS. 3 a, b and c illustrate different alternatives as transversal cross-sections of FIG. 2,
FIGS. 5 a, b and c illustrate scrubbing tubes operated with different scrubbing methods, and
FIGS. 6 a and b, illustrate embodiments of FIG. 1.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In the scrubber embodiment of FIG. 1, it is apparent that the gas to be scrubbed enters through at least three, in this case four scrubbing tubes 1. In the case of FIG. 1, the tubes are venturi tubes. As is seen, gas is conducted tangentially into the venturi, but it can also be conducted in a straight line. The scrubbing tubes 1 are located in a scrubbing chamber 4 formed by the space left in between the outer cylinder 2 and the next cylinder, i.e. the distribution cylinder 3, symmetrically above the scrubbing chamber. The gases to be conducted to the separate scrubbing tubes do not have to be mutually similar; one part may come for instance from a submerged evaporator connected to the regeneration unit of pickling acids, a second part from the delay crystallizer of the same regeneration process, and a third part from some other unit of the regeneration creating flue gases, etc. As is seen in FIG. 2, on the bottom of the scrubbing chamber 4, there is water or other scrubbing liquid 5 used in the washing of gases. The bottom of the scrubbing chamber can be conical, or it may have a flat bottom.
FIG. 3a illustrates how the interior of the scrubbing chamber is provided with partition walls 6, extending from the outer cylinder to the distribution cylinder 3, so that the gas emitted from each scrubbing tube is directed, through the channel formed by the specific partition walls, to an inner swirl chamber 7. In the top part of the distribution cylinder 3, above the liquid surface, there are provided apertures 8, through which gas flows into the swirl chamber. The number of the partition walls is always the same as that of the scrubbing tubes. The partition walls 6 are constructed to be inwardly turnable, so that for each gas flow they form a channel which is tangential with respect to the inner cylinder 9. Of course the partition walls do not necessarily have to be tangential, the main thing is that they force the gases to a rotary motion. Thus the gases are set to rotary motion in the swirl chamber 7 formed in between the distribution cylinder and the inner cylinder 9 therein, and in this swirl chamber there is formed a uniform whirl flow of scrubbed and saturated gas, which is released inside the cylinder 9 as an even, symmetrical whirl rotating at a increasing speed.
In the swirl chamber 7, the separate gas flows are combined and flow upwards as one uniform flow. It is pointed out that the change of direction for the gases is carried out essentially above the free liquid surface. This removes the major part of the liquid and reduces the load of the droplet separator. As is seen in FIGS. 3b and 3c, particularly in cases where the feeding of some gas to be scrubbed is desired to be interrupted, it is possible to furnish the scrubber with blade extensions 10 provided with hinges in between the cylinders 3 and 9. The blade extension 10 may be constructed movable, so that it closes in a flap-like fashion, if for instance gas does not flow in through a given section. The flap may be closed by overpressure, or it can be done manually or automatically. In FIG. 3b, all blade extensions are in a closed position, and in FIG. 3c all blade extensions are open.
In the vertical direction, the partition walls 6 extend from the top edge of the scrubbing chamber to below the liquid surface, so that the gas is always forced to whirling motion when flowing into the swirl chamber. In the swirl chamber, and further in the inner cylinder 9, the rotation of the gases causes the solid particles and liquid drops to be released from the gas to the liquid. A possible carrying away of the liquid droplets to the gas flow from the liquid surface can further be prevented by some suitable arrangement, for instance by using a preventive cone. By arranging a water washing in the inner surface of the inner cylinder 9, the particles or harmful gas components still remaining in the gas flow and emitted on the walls in the cylinder 9 can be absorbed in a water film flowing down along the wall and conveyed into the washing liquid 5. The scrubbed, droplet-free saturated gas is drained through the innermost cylinder, i.e. the drain cylinder 11, which is located in the middle of the scrubbing tubes.
Consequently an effective droplet separation, achieved with structures of maximal simplicity, is in the apparatus of the present invention realized as follows: the gas flows, discharged from three or more scrubbing tubes and colliding with scrubbing liquid collected on the bottom of the scrubber, are turned from mainly vertical direction to horizontal direction, and directed advantageously tangentially to droplet separation. The gases are combined, and in the next cylindrical swirl chamber (scrubbing chamber) they are formed into a symmetrical whirl field strengthening towards the center and forced into another swirl chamber, where the liquid droplets contained in the gas are discharged on the walls of the cylinder 9, whereafter the whirl flow is drained from the droplet separator through the still smaller drain cylinder 11.
Owing to the operation of the above described four nested cylinders, the scrubber is called FCS (Four Cylinder Scrubber). As is seen in the drawings, the cylinders are all concentric, so that the diameter of the inner cylinder is always shorter than that of the previous cylinder.
According to FIG. 4a, the different gas flows 12 can be combined already before the scrubbing tubes by conducting all to the front chamber 13, wherefrom they can be symmetrically distributed to the different scrubbing tubes. Advantageously the front chamber is arranged so that it surrounds the drain cylinder 11, in which case the draining gases 14 are heated up to a temperature where the gases are not recondensed, even if the drain tube walls are cold. This is particularly advantageous from the point of view of preventing corrosion. In the embodiment of FIG. 4b, the draining gases 14 flow, after the drain cylinder 11, through a heat exchanger tube arrangement 15, formed inside the front chamber 13, which arrangement heats the draining gases 14 even more effectively than the previous method.
As was pointed out above, a venturi scrubber is not the only scrubber alternative, but the scrubbing tubes may be based on other known principles as well. FIGS. 5, a, b and c, illustrate various structural alternatives for the scrubbing tubes; FIG. 5a illustrates a scrubbing tube 16 operated according to the centrifugal scrubbing principle; FIG. 5b illustrates a scrubbing tube 17 filled with filler particles; and FIG. 5c illustrates a scrubbing tube 18 operated according to the spray principle. The essential feature is, however, that the scrubbed gas entering from all these scrubbing tubes is conducted into a uniform droplet separator constructed of four nested cylinders, above which droplet separator, or alternatively at the sides whereof, the tubes are advantageously arranged. Another essential feature is that in the swirl chamber, the gases are set to a whirling motion, so that the droplets are separated from the gas.
The invention is further described with reference to the appended examples.
EXAMPLE 1
Three different gases must be scrubbed, so that gas A is fed from one process unit, gas B is fed from two process units and gas C from three process units. There are at least two different solutions.
SOLUTION 1
According to FIG. 6a, there are used water-spray operated venturis, three in number. Gas A enters the venturi 19, gases B are combined prior to the venturi 20, and gases C are likewise combined prior to the venturi 21. Thus the venturis are separate, according to FIG. 6a, and the discharge gases are not reheated.
SOLUTION 2
There is provided a front chamber 22 according to FIG. 4a, as is illustrated in FIG. 6b. Into this front chamber, there are conducted A-gases, B-gases and C-gases through six symmetrically positioned tubes, in which case all of the gases in a way obtain the same position and are combined in the front chamber. The position of the tubes 23 (indicated with arrows) feeding to the chamber can be directed towards the front chamber from the side, from the top or even tangentially. In this case the temperature of the pure, saturated gas can be increased by making use of the higher temperature of the new gases entering the process.
EXAMPLE 2
The gases to be scrubbed contain nitric oxides, sulphur oxides and hydrogen fluorides which are created when aerating the equipment facilities of the so-called OPAR process (OPAR=Outokumpu Pickling Acid Recovery, see for example Proceedings of CIM Svmoosium on Iron Control in Hvdrometallurgy, Toronto, Oct. 19-22, 1986). The first gas type is a 145° C. gas from a submerged evaporator, flow rate 1000 Nm 3 /h, containing all of the above mentioned components. The second gas type, containing mainly nitric oxides, is sucked from two delay crystallizers located outside. The gas temperature is 80° C., and the flow rate from both crystallizers 500 Nm 3 /h. The third gas, likewise containing nitric oxides but with lower contents, is sucked from three points located inside the said pickling acid regeneration plant. In this fashion, the regeneration salt concentrator, the pump tank of the salt filter, and the pump tank collecting overflow from the concentrator, are all aerated. The temperature of these gases, too, is 80° C., and the flow rate from the points of each location roughly 350 Nm 3 /h.
It could have been possible to arrange the said multigas scrubbing according to the solution 1 of Example 1, by using a separate venturi for each gas type as is illustrated in FIG. 1. Because, however, the said gases are nearly dust-free, and because it was also desired to heat the scrubbed gas above the dewpoint, a multigas scrubbing process was chosen for this case--following the procedure of solution 2 of Example 1.
The employed scrubber is provided with a front chamber as in the embodiments of FIGS. 4a and 6a. The gases to be scrubbed are conducted into the top part of the cylinder, through six tubes located symmetrically with respect to each other. In the front chamber, the gases are mixed with each other while the temperature in this case sets at about 115° C. in the top part of the chamber. While flowing through the chamber, the gases are cooled by nearly ten degrees, whereas the cleaned gas flows in the drain tube passing through the chamber and is heated a little more. The employed scrubbing solution is acid water in the scrubbing, which is circulated, via the cooler, to the said venturis beginning from the front chamber.
The scrubbing result is improved from what it was when using large separate venturis. The symmetrical multiscrubber structure promotes a good gas/scrubbing solution contact. Another important factor is the pre-mixing of gases to be scrubbed, which balances the load of the scrubber. Moreover, the running and adjusting of this scrubber is easier than the controlling of several separate scrubbers. By incorporating the flue gases from the delay crystallizer of the OPAR process into the scrubbing circuit, the recovery of regenerated nitrogen was increased from 97% to 98,5%, i.e. nearly as high as the recovery of fluoride (99%). The scrubbing solution collected from the scrubbing could thus be used as a pickling acid for refined steel, together with the acid formed elsewhere in the regeneration process. Thus the multigas scrubber producing a homogeneous scrubbing solution, whereby the recovery of both nitrogen and fluoride are increased to nearly 100%, helps adjusting the composition of the pickling acids, and thus the pickling process itself. | The invention relates to an appparatus where the wet scrubbing of several different gas flows is carried out in at least three scrubbing towers, and the droplet separation of scurbbed gases takes place in a cyclonic, uniform droplet separator constructed of several cylinders, so that the obtained product is a pure and droplet-free gas. | 1 |
CROSS RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 11/641,543 filed Dec. 18, 2008, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/751,362 filed Dec. 16, 2005, and is a continuation-in-part of U.S. patent application Ser. No. 11/354,583 filed Feb. 14, 2006, which claims the benefit of U.S. Provisional Application Ser. No. 60/652,922 filed Feb. 14, 2005; a continuation-in-part of U.S. patent application Ser. No. 11/342,240 filed Jan. 27, 2006, now U.S. Pat. No. 7,638,195, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/648,327 filed Jan. 27, 2005; and a continuation-in-part of U.S. patent application Ser. No. 11/225,607 filed Sep. 12, 2005, now U.S. Pat. No. 7,553,904 issued Jun. 30, 2009 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/608,582 filed Sep. 10, 2004), which is a continuation-in-part of U.S. patent application Ser. No. 11/166,008 filed Jun. 24, 2005, which is (a) a continuation of U.S. patent application Ser. No. 09/631,892 filed Aug. 4, 2000, now U.S. Pat. No. 6,972,312 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/147,435, filed Aug. 4, 1999); (b) a continuation of U.S. patent application Ser. No. 10/351,292, filed Jan. 23, 2003, now U.S. Pat. No. 6,933,345 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/351,523, filed Jan. 23, 2002), which is a continuation-in-part of U.S. patent application Ser. No. 09/818,265, filed Mar. 26, 2001, now U.S. Pat. No. 6,716,919 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/192,083, filed Mar. 24, 2000); (c) a continuation of U.S. patent application Ser. No. 09/747,762, filed Dec. 21, 2000, now U.S. Pat. No. 6,911,518 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/171,888, filed Dec. 23, 1999); and (d) a continuation of U.S. patent application Ser. No. 10/186,318, filed Jun. 27, 2002, now U.S. Pat. No. 6,927,270 (which claims priority from U.S. Provisional Patent Application Ser. No. 60/301,544, filed Jun. 27, 2001). The disclosures of the foregoing applications are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to methods for enhancing the bulk and surface properties of a polymer through use of POSS nanostructured chemicals as dispersion aids, surface modifiers, and interfacial friction modifiers.
BACKGROUND OF THE INVENTION
[0003] It is common practice to modify particulates of polymer, organic, inorganic, man-made or natural origin materials with silane coupling agents, surfactants, polymeric coatings, chemical oxidation treatments, chemical reduction treatments, hot and cold treatments, and radiation exposures in attempts to alter the surface properties of the particle with itself or with a secondary material, or to improve its dispersive characteristics.
[0004] Prior art associated with particulates, coatings, and processing techniques has not been able to precisely control particulate and material surface properties and surface-surface interactions at the 1 nm to 50 nm level. Therefore, a need exists for surface modification agents and techniques to provide such control.
SUMMARY OF THE INVENTION
[0005] The present invention describes methods of dispersing particulates into a polymer by controlling its surface properties at the nanoscopic level with the use of nanostructured chemicals. The method is highly desirable for the creation of chemical masterbatches. This invention also teaches a method of controlling the surface and interfacial properties of polymeric, metallic, ceramic, and surfaces derived from natural, man-made or biological materials by controlling their nanoscopic surface topology, surface area, and associated volume via nanostructured chemicals. Such surface control can be applied in both remedial and original manufacturing.
[0006] The invention solves the problem of dispersing nano and macroscopic particulates at high concentrations within a polymer matrix. The solution is enabled uses nanostructured chemicals as dispersion aids and surface modifying agents within polymeric materials and on particulate surfaces. The invention also provides a means for reducing the friction of surfaces through the use of the same nanostructured chemicals as interfacial modifiers.
[0007] The use of POSS nanostructured chemicals for control of particulate dispersion in polymers is useful for the preparation of highly concentrated particulate masterbatches. The purpose of the masterbatch is to provide performance enhancing additive concentrates in an easily dilutable form. Masterbatches are desired by formulators, molders, and polymer converters as they provide a convenient method of increasing the value of common plastics and are lower-cost to ship than a fully diluted product. The ability to increase the concentration, complexity, number, and type of additives that can be incorporated into a masterbatch enables additional functionality and further increases value.
[0008] Combination of three primary material are preferred for masterbatch compositions: (1) POSS nanostructured chemicals, POMS metallized nanostructured oligomers, or metal containing nanostructured polymers; (2) polymers or polymer/monomer combinations including traditional amorphous polymer systems such as acrylics, carbonates, epoxies, esters, silicones, polyolefins, polyethers, polyesters, polycarbonates, polyimides, polyamides, polyurethanes, phenolics, cyanate esters, polyureas, resoles, polyanilines, fluoropolymers, and silicones and polymers containing functional groups; traditional semicrystalline and crystalline polymer systems such as styrenics, amides, nitriles, olefins, aromatic oxides, aromatic sulfides, and esters; or ionomers or traditional rubbery polymer systems derived from hydrocarbons and silicones; and (3) nanoscopic and macroscopic particulates including metals, metal alloys, oxides, ceramic, ceramic alloys, microtubes, nanotubes, inorganic, organic, and any particulate of man-made or natural origin.
[0009] The nanostructured chemical can be utilized to surface functionalize a particle prior to or during masterbatch mixing. It can be added to the polymer followed by addition of the particulate filler or can be added simultaneously with the polymer and filler in a sequence that provides the most desirable performance and economic advantages.
[0010] Preferably, the process of particulate dispersion occurs by combining together the components of interest and effecting the surface and interfacial modification through mixing. All types and techniques of blending, and mixing including melt blending, dry blending, grinding, milling, solution blending, reactive and nonreactive mixing are also effective.
[0011] In addition, because of their chemical nature, POSS nanostructured chemicals can be tailored to show compatibility or incompatibility with nearly all polymer, biological, organic, and inorganic systems. Their physical size in combination with their tailorable compatibility enables nanostructured chemicals to be selectively incorporated into plastics, and to control the dynamics of coils, blocks, domains, and segments, and subsequently favorably impact a multitude of physical properties. The properties most favorably improved are time dependent mechanical and thermal properties such as viscosity, friction, solubility, dispersion, heat distortion, creep, shrinkage, compression set, modulus, hardness, abrasion resistance, electrical resistance, electrical conductivity, radiation absorption, luminescence, emissivity, degree of cure, biological compatibility and biological function. In addition to mechanical properties, other physical properties that are favorably improved include thermal conductivity and electrical conductivity, fire resistance, and gas barrier and gas and moisture permeation properties, which are selectively controlled depending on cage size, composition and homogeneity of distribution.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 illustrates the representative volume contributions of a 1.5 nm POSS molecule;
[0013] FIG. 2 illustrates the impact of surface area relative to weight % loading of POSS;
[0014] FIG. 3 illustrates the volume contribution relative to weight % loading of POSS;
[0015] FIG. 4 illustrates representative examples of POSS nanostructured chemicals;
[0016] FIG. 5 illustrates different surface topology for cages bound to a surface by one or three reactive groups;
[0017] FIG. 6 illustrates the use of a nanostructured chemical to increase the surface area of a particle;
[0018] FIG. 7 illustrates the use of a nanostructured chemical to decrease the amount of surface in contact with a projectile particle;
[0019] FIGS. 8( a ) and 8 ( b ) illustrate the use of nanostructured chemicals to increase the brightness of TiO 2 dispersions in polypropylene. FIG. 8( a ) is a dispersion of polypropylene containing 5 wt % SO1450 and 1 wt % nanoscopic TiO 2 . FIG. 8( b ) is a dispersion of polypropylene with 1 wt % nanoscopic TiO 2 ;
[0020] FIG. 9 is a transmission electron micrography comparison of (A) 5 wt % SO1450 dispersed in polypropylene, (B) 100 nm average diameter of nano-TiO 2 dispersed in polypropylene at 1 wt % level, and (C) 50 nm average diameter of nano-TiO 2 dispersed in polypropylene containing 5 wt % SO1450 and 1 wt % nano-TiO 2 ;
[0021] FIG. 10 illustrates the surface of a polypropylene control; and
[0022] FIG. 11 illustrates the surface of a 10% MS0825 POSS/polypropylene formulation.
DEFINITION OF FORMULA REPRESENTATIONS FOR NANOSTRUCTURES
[0023] For the purposes of understanding this invention's chemical compositions the following definition for formula representations of Polyhedral Oligomeric Silsesquioxane (POSS), Polyhedral Oligometallosesquioxane (POMS) and Polyhedral Oligomeric Silicate (POS) nanostructures is made.
[0024] Polysilsesquioxanes are materials represented by the formula [RSiO 1.5 ] ∞ where ∞ represents molar degree of polymerization and R=represents an organic substituent (H, siloxide, siloxy, cyclic or linear aliphatic or aromatic groups that may additionally contain reactive functionalities such as alcohols, esters, amines, ketones, olefins, ethers or halides). Polysilsesquioxanes may be either homoleptic or heteroleptic. Homoleptic systems contain only one type of R group while heteroleptic systems contain more than one type of R group. As a special case R may also include fluorinated organic groups.
[0025] POSS, POMS, and POS nanostructure compositions are represented by the formula:
[0026] [(RSiO 1.5 ) n ] Σ# for homoleptic compositions
[0027] [(RSiO 1.5 ) n (R′SiO 1.5 ) m ] Σ# for heteroleptic compositions (where R≠R′)
[0028] [(RSiO 1.5 ) n (RXSiO 1.0 ) m ] Σ# for functionalized heteroleptic compositions (where R groups can be equivalent or inequivalent)
[0029] [(RRSiOhd 1 . 5 ) n (RSiO 1.0 ) m (M) j ] 93 # for heterofunctionalized heteroleptic compositions
[0030] In all of the above R is the same as defined above and X includes but is not limited to OH, Cl, Br, I, alkoxide (OR), acetate (OOCR), peroxide (OOR), amine (NR 2 ), isocyanate (NCO), and R. The symbol M refers to metallic elements within the composition that include high and low Z metals including s and p block metals, d and f block transition, lanthanide, actinide metals, in particular, Al, B, Ga, Gd, Ce, W, Ni, Eu, U, Y, Zn, Mn, Os, Ir, Ta, Cd, Cu, Ag, V, As, Tb, In, Ba, Ti, Sm, Sr, Pt, Pb, Lu, Cs, Tl, and Te. The symbols m, n and j refer to the stoichiometry of the composition. The symbol Σ indicates that the composition forms a nanostructure and the symbol # refers to the number of silicon atoms contained within the nanostructure. The value for # is usually the sum of m+n, where n ranges typically from 1 to 24 and m ranges typically from 1 to 12. It should be noted that Σ# is not to be confused as a multiplier for determining stoichiometry, as it merely describes the overall nanostructural characteristics of the system (aka cage size).
DETAILED DESCRIPTION OF THE INVENTION
[0031] The present invention recognizes that significant property enhancements can be realized by the modification of particulate and polymer surfaces with nanostructured chemicals. This greatly simplifies surface modification since the prior art does not control surface area, volume, or nanoscopic topology, and does not function as interfacial control agents nor as alloying agents within polymer morphology or between dissimilar materials.
[0032] The prior art is deficient in recognizing and establishing control over nanoscopic surface features. The present invention demonstrates that properties such as dispersion, viscosity, surface energy, lubricity, adhesion, and stain resistance can be easily and favorably controlled through use of nanostructured chemicals at material surfaces and interfaces. Properties most favorably improved are time dependent mechanical and thermal properties such as particle dispersion, dispersion stability, heat distortion, creep, compression set, strength, toughness, visual appearance, feel, and texture, shrinkage, modulus, hardness and abrasion resistance, impact resistance, fire resistance, shrinkage reduction, expansion reduction, adhesion, lubricity, conductive, dielectric, capacitive properties, degree of cure, rate of cure, radiation absorptive properties and biological activity. In addition other physical properties are favorably improved, including gas and moister permeability, paint, print, film and coating properties.
[0033] The fundamental premise behind surface modification in this invention is underpinned mathematically through computation of the surface area and volume contribution provided at various loadings of 1 nm spherical nanostructured chemical particles either into or onto a material. Computation reveals that as a particle becomes smaller it contributes more surface area and more volume as a wt % of its incorporation into a material than would larger particles (see FIGS. 1-3 ). The net effect is that even small loadings of sufficiently small nanoparticles can ultimately dominate the surface characteristics of a material. The new surface provided by nanomodification can be utilized to either decrease surface roughness by filling-in surface defects or can increase surface roughness by creating more surface. Furthermore, it can be utilized to either increase or decrease the surface-surface interaction between two or more materials by making their surfaces smoother or rougher. The material surfaces can be similar or dissimilar, and of man-made or of natural or biological origin.
[0034] Practical applications of this invention require the use of nanoscopic particulate-like entities. Most desirably, such particles would have a known and precise chemical composition, rigid three dimensional shape, controllable diameter, and controllable surface chemistry. Nanostructured chemicals meet such requirements and are preferably employed in this invention.
[0035] Nanostructured chemicals are best exemplified by those based on low-cost Polyhedral Oligomeric Silsesquioxanes (POSS) and Polyhedral Oligomeric Silicates (POS) and Polyhedral Oligometallosesquioxanes (POMS). FIG. 4 illustrates some representative examples of monodisperse POSS nanostructured chemicals. However, logical extensions of nanoscopic chemicals include carboranes, polyoxometallates, and POMS, and are also contemplated in this invention. POMS are nanostructured POSS chemicals that contain one or more metals inside or outside the central cage framework. In certain instances, cages may contain more than one metal atom, or more than one type of metal atom or even metal alloys in or on the cage.
[0036] POSS nanostructured chemicals contain hybrid (i.e. organic-inorganic) compositions and cage-like frameworks that are primarily comprised of inorganic silicon-oxygen bonds which may also contain one or more metal atoms bound to the cage. In addition to the metal and silicon-oxygen framework, the exterior of a nanostructured chemical is covered by both reactive and nonreactive organic functionalities (R), which ensure compatibility and tailorability of the nanostructure with other substances. Unlike particulate fillers, POSS nanostructured chemicals dissolve into polymers and solvents and exhibit a range of melting points from −40° C. to 400° C.
[0037] POSS nanostructured chemicals bearing metal atoms (POMS), silanols, alcohols, amines or other polar groups are preferably utilized as dispersion and surface modification agents because they can chemically interact and even permanently bond to the surface of silica, metallic or polymer particles while nonreactive groups on the cage can compatibilize the surface toward a secondary material or secondary surface. The chemical nature of POSS nanostructured chemicals also renders their dispersion characteristics to be governed by the Gibbs free energy of mixing equation (ΔG=ΔH-TΔS) rather than kinetic dispersive mixing as for insoluble particulates. Thus, the ability of POSS to interact with a surface through Van der Waals interactions, covalent, ionic, or hydrogen bonding can be utilized to chemically, thermodynamically, and kinetically drive their dispersion and surface modification. Furthermore, since POSS cages are monoscopic in size, entropic dispersion (ΔS) is favored.
[0038] Each POSS nanostructured chemical also has a molecular diameter that can be controlled through variation of cage size and the length of the cage R groups attached to the cage (typical range from 0.5 nm to 5.0 nm). The molecular diameter is key to providing control over surface topology, surface area, and volume contributions in optimal formulations. For example, a cage bound to a surface by three silanol groups provides a lower topological profile than a cage bound at one vertice ( FIG. 5 ).
[0039] Additionally, the topological control that POSS cages offers can be used advantageously as bumps on a surface ( FIG. 6 ). The resulting surface roughness will increase the amount of bondable surface area and can be utilized to disrupt the interaction of filler particulates with each other. It is well known that filler-filler interactions lead to self-quenching, agglomeration and inefficient dispersion of fillers and additives. POSS greatly reduces filler-filler interactions and self association by providing a nanoscopic spacer on the surface of particles and between polymer chains.
[0040] Consequently, POSS surface modification can reduce surface friction by decreasing the areal contact between two surfaces. Because POSS cages are molecules they can also melt and thereby reduce friction through nanoscopic surface lubrication and through isoviscous flow. This feature is particularly attractive for use in low friction fabrics, bandages, films, fabrics, tapes, and clothing.
[0041] The use of POSS to promote lower surface friction is beneficially utilized in sabots and shotgun wadding to retain projectile kinetic energy ( FIG. 7 ) against loss from barrel friction and aerodynamic drag. As a projectile translates the interfacial friction is reduced through lubrication by POSS R groups and also reduces barrel fouling.
[0042] Furthermore, the use of POSS nanostructured chemicals is very cost effective because only a small amount is needed to greatly increase the surface area ( FIG. 2 ). Computations indicate that a 1 wt % incorporation of POSS onto a material provides a billion nm 2 /g increase in surface area. Thus the incorporation of small amount of POSS is both economically and technically effective at dominating surface area.
EXAMPLES
General Process Variables Applicable to all Processes
[0043] As is typical with chemical processes, there are a number of variables that can be used to control the purity, selectivity, rate and mechanism of any process. Variables influencing the process for the incorporation of nanostructured chemicals (e.g. POSS, POMS, POS) into plastics includes the size, polydispersity, topology, composition, and rigidity of the nanostructured chemical. Similarly the molecular weight, polydispersity and composition of the polymer system must also be matched with that of the nanostructured chemical. Finally, the kinetics, thermodynamics, and processing aids used during the compounding process are also tools of the trade that can impact the loading level and degree of enhancement resulting from incorporation of nanostructured chemicals into polymers. Blending processes such as melt blending, dry blending, milling, grinding, and solution mixing blending are all effective in utilizing nanostructured chemicals. Continuous, semicontinuos, and batch process methods of incorporation can be used.
[0044] Methods for application include master batching, mixing, blending, milling, grinding, and thermal or solvent assisted methods including spraying and vapor deposition. Masterbatching is particularly desired because it affords automated and continuous production and consequent cost saving advantages. The incorporation of a nanostructured chemical into or onto a particle polymer favorably impacts a multitude of physical properties.
Example 1
Masterbatch Dispersion of Particles
[0045] POSS trisilanols were added to metallic particles by dissolving the POSS in dicholoromethane followed by addition of the metal particle powder. The solvent was then recovered under reduced pressure and the solid was heated to promote bonding of the POSS to the surface through Si—O—M bond formation.
[0046] POSS trisilanols were added to thermoplastic polymers by melt compounding followed by addition of metallic particles and additional melt compounding. Similarly POSS trisilanols and metallic powders were added to a polymer during melt compounding followed by extrusion and pelletizing of the final composition. A striking observation was an increased bright whiteness of the systems utilizing POSS trisilanols and nanoscopic titanium dioxide as compared to formulations without the POSS surface modification ( FIG. 8 ).
[0047] In addition to increased brightness, the use of POSS trisilanols resulted in finer particle sizes and more uniform distributions than could be obtained without nanoscopic surface modification. The dispersion level of the POSS within the polymer with and without the metallic particle is provided as evidence of the ability to create masterbatches with enhanced dispersion ( FIG. 9 ).
[0048] Specific combinations of POSS with polymer and fillers are necessary to obtain optimal dispersions and masterbatch concentrations. For example heptaisoOctyl POSS trisilanol #SO1455, TrisilanolisoButyl POSS #SO1450, or OctaisoButyl POSS #MS0825, are most preferably utilized with polyethylene, polypropylene and related polyolefins. While masterbatch concentrations of POSS at greater than 20 wt % can be utilized, loading levels of 0.1 wt % POSS are effective at creation of stable dispersions.
[0049] Masterbatches of polar thermoplastics such as polyamides, polyethers, polycarbonates, polyesters, and polyurethanes preferably utilize trisilanolphenyl POSS #SO1458 or trisilanolisoOctyl POSS #SO1455. While masterbatch concentrations of POSS at greater than 20 wt % can be utilized, loading levels of 0.1 wt % POSS are also effective at creation of stable dispersions.
[0050] Masterbatches containing 75% by weight of inorganic solid such a Gd 2 O 3 can be achieved while maintaining high levels of dispersion and processability into molded articles.
Example 2
Topographic Control of Molded Plastics
[0051] Masterbatches containing 5 and 10 wt % Octaisobutyl POSS (#MS0825) and polypropylene (PP) were prepared utilizing a continuous co-rotating twin screw extruder with an L:D ratio of 40:1. Surface topography measurements were made by hot pressing the extrudate between clean silicon wafers and conducting tapping mode surface topography. The relative surface roughness from incorporation of 10% MS0825 POSS increased four fold (from 0.61 nm for PP) ( FIG. 10 ) to 2.23 nm for the POSS-PP ( FIG. 11 ). The topographical measurements verify the control of surface roughness at the nanoscopic length scale and the uniform incorporation of MS0825 POSS throughout the PP in 1.5-50 nm domains.
Example 3
Surface Friction Control
[0052] Surface topology control necessarily renders control over surface friction properties. Nanoscale surface friction studies were performed via AFM in lateral force mode (LFM) on 1 μm×1 μm scan size for master batches of POSS in thermoplastic polymers. Relative coefficient of friction (μ) is defined as the ratio of the total lateral friction force (F f ) to the total normal force (F N ). In LFM AFM, the surface is scanned in the direction perpendicular to the long axis of the cantilever and the probe experiences a friction force in the direction opposite to the scanning direction. The relative coefficient of friction for PP, and PP masterbatches containing 5 wt. % and 10 wt. % MS0825 POSS is shown in Table 1. The incorporation of 10 wt. % MS0825 POSS in PP results in an almost 60% reduction in relative coefficient of friction (COF). The reduction in surface friction renders polymers containing POSS useful for low friction textiles and molded articles.
[0000]
TABLE 1
Comparisons of adhesion and friction
for PP MS0825 POSS masterbatches
Relative Adhesive Force
(nN)
% COF
Composition
COF
Intercept
Force Curve
Reduction
PP control
0.17
37.77
30.76
—
PP/5% MS0825 POSS
0.14
20.57
17.35
18
PP + 10% MS0825 POSS
0.07
26.29
15.02
59
Example 4
Friction Reduction of Projectiles
[0053] As illustrated in FIG. 7 , nanostructured chemicals can be utilized to decrease the surface area and subsequent coefficient of friction for dissimilar surfaces. This application is particularly attractive for application as low friction projectiles.
[0054] A series of 0.22 cal rimfire and 0.50 cal true-to bore bullets were coated with various POSS nanostructured chemicals and their ballistic properties were measured. Given the use of lead and copper in bullets, POSS cages functionalized with silanol groups and thiol groups were found to be particularly adherent to the bullets due to the formation of strong bonds to the metal.
[0055] Each of the bullets was cleaned prior to coating to remove particulates. The bullets were then dipped into a solution containing dichloromethane and dissolved POSS. The preferred POSS systems that are useful for such application are heptaisoOctyl POSS trisilanol (#SO1455) and heptaisoOctylPOSSpropylthiol (#TH1555) in solution loadings from 0.1 wt % to 10 wt %. The bullets were then air dried.
[0056] Ballistic testing was conducted using a fire-arm which was cleaned before and after firing. The purpose of the cleaning was to examine the amount of residue and to avoid cross contamination. A noticeable improvement in both bullet velocity and reduction of bullet drop was observed as well as reduction in barrel residue (fouling) (Table 2). Such enhancements are of great value to sportsmen, law enforcement and the military.
[0000]
TABLE 2
Comparison of ballistics for 0.22 caliber bullets
Bullet Caliber 0.22
Ave. Vel.
Std deviation
Coating
ft/sec
ft/sec
Trajectory drop
Control
1046
70.75
bullets dropped 7″ at 60 yds
TH1555
1064
35.45
bullets dropped 4.5″ at 60 yds
SO1455
1062
14.24
bullets dropped 4.5″ at 60 yds
Example 5
Friction Reduction of Sabots
[0057] The use of nanoscopic POSS to attain low friction polymer surfaces is also desirable for sabots to reduce energy loss. A wide series of POSS polyolefin and polyamide masterbatches were prepared and injection molded into shotgun wads. The wads were then loaded with 1.25 oz of #2 steel shot using same-lot, factory controlled powder loadings. The rounds were then fired and both shot velocity and pattern were measured (Table 3). The findings indicated and increase in shot velocity and significantly tighter shot pattern. Such enhancements are of great value to sportsmen, law enforcement and the military. The combination of POSS coated projectiles and low friction sabots is also envisioned.
[0000]
TABLE 3
Comparison of ballistics for 12 gauge steel-shot shotgun wads.
Ave. Shot
Velocity
Resulting Shot
Composition
ft/sec
pattern
Wad flight distance
LDPE Control
1342
modified choke
LDPE 5 wt %
1364
equivalent to
wad traveled 20 yds further
MS0825
full choke
LDPE 5 wt %
1364
equivalent to
wad traveled 18 yds further
SO1450
full choke
LDPE 5 wt %
1356
modified-full
wad traveled 10 yds further
MS0830
choke pattern
[0058] While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the methods and apparatus disclosed herein may be made without departing from the scope of the invention which is defined in the appended claims. | A method of using metallized and nonmetallized nanostructured chemicals as surface and volume modification agents within polymers and on the surfaces of nano and macroscopic particulates and fillers. Because of their 0.5 nm-3.0 nm size, nanostructured chemicals can be utilized to greatly increase surface area, improve compatibility, and promote lubricity between surfaces at a length scale not previously attainable. | 1 |
BACKGROUND OF THE INVENTION
[0001] This invention concerns radiation therapy, especially brachytherapy, for treating tissues which may have diffuse proliferative disease. In brachytherapy, the radiation source is generally placed within a surgically created or naturally occurring cavity in the body. In particular, this invention relates to an applicator for delivering radiation therapy to a vaginal cavity and/or to adjacent tissue, often following surgical treatment of cancer. Radiation therapy of this sort is generally administered over a period of time in partial doses, or fractions, the sum of which comprises a total prescribed dose. This fractional application takes advantage of cell recovery differences between normal and cancerous tissue whereby normal tissue tends to recover between fractions, while cancerous tissue tends not to recover.
[0002] In brachytherapy, a prescribed dose is selected by the therapist to be administered to a volume of tissue (the target tissue) lying outside the treatment cavity into which the radiation source will be placed. Generally the prescribed dose will include a minimum dose to be delivered at a preferred depth outside the treatment cavity (the prescription depth). Since, in accordance with the laws of physics, radiation intensity falls off with increasing distance from the radiation source, it is desirable to create and maintain a space between the source of radiation and the first tissue surface to be treated (generally the cavity wall since the source is placed within the cavity) in order to moderate the absorbed dose at the cavity surface. Although not always the case, generally the absorbed dose at the prescription depth outside the cavity is to be uniform. In this isotropic case, it is therefore important that the incident radiation on the interior surface of the cavity be the same at all points being treated. To accomplish this objective, it may be necessary to sequentially position a single radiation source through a series of positions (or utilize multiple sources strategically placed) which, in the aggregate, produce a uniform absorbed dose incident on the cavity surface being treated. When this is achieved, the absorbed dose reaching into tissue will be the same at all points being treated, and the minimum prescribed dose can be delivered at the prescription depth as nearly as the treatment plan will allow. Furthermore, by selecting the radiation source intensity (radioisotope emissions or x-ray tube output) and controlling treatment time and the distance from the source(s) to the cavity interior surface, the incident radiation can be sufficiently moderated to avoid substantial damage to normal tissue.
[0003] Rigid applicator cylinders designed to receive radioisotopes have traditionally been used to treat vaginal cancer or malignancies in adjacent tissues. A principal function of an applicator is to establish and maintain distance relationships between the radiation source and the tissues being treated such that the prescribed dose is delivered to a desired prescribed depth of tissue, and yet normal tissues nearest the radiation source are not subjected to absorbed doses sufficient to risk significant necrosis. Applicators of this general type are available, for example, from Varian Medical Systems, Inc., Charlottesville, Va. Such prior art applicator cylinders are sized to the vaginal cavity or adjacent anatomy, but because the tissues should be positioned closely against the exterior surface of the applicator, large applicators must be chosen that are often painful on insertion, and once inserted may fail to provide a good fit. Additionally, prior art cylinders are generally straight, with a central lumen into which radioactive seeds are delivered and later removed after completion of prescribed therapy. As a result, anisotropic treatment plans are difficult to achieve with such symmetrical applicators. Thus conventional applicators are less than ideal in many cases.
SUMMARY OF THE INVENTION
[0004] Although this invention is disclosed with specific reference to therapeutic application of radiation within the vagina, the principles of the invention may be similarly applied to other brachytherapy situations in other natural or surgically created anatomic spaces, or to therapeutic situations other than post-surgical treatment of cancer, and still fall within the bounds of this invention. The term “proximal” as used herein refers to the end of the element being described which is nearest the therapist when in use, while the term “distal” refers to the end farthest from the therapist, and which is generally inserted into the patient.
[0005] The applicator of this invention comprises a polymeric sleeve exhibiting substantially elastomeric behavior, particularly diametrally, an end of which sleeve can be turned inside-out on itself along at least part of its length. The opposite end of the sleeve can be fastened to, or is monolithic with one end of a substantially rigid or semi-rigid, cylindrical, tubular mandrel which extends axially away from the sleeve. The open end of the sleeve (opposite the mandrel) further comprises a diametral transition section terminating in a cuff or handle, the outer diameter of which is larger than the vaginal opening of the patient in order to prevent entry of the applicator cuff into the vagina. When the cuff and attached everted portion of the sleeve are restrained axially relative to the mandrel and the mandrel is advanced through the cuff, the body of the sleeve progressively everts until the inner surface of the sleeve becomes the new outer surface of the applicator. The mandrel further comprises an axial lumen sized to accommodate a radiation source (and source catheter if any), said source extending at least from the end of the mandrel opposite the end connected to the sleeve for a length sufficient to allow positioning of the radiation source for delivery of the prescribed therapy. Beyond this length, the lumen may extend to join that of the sleeve, or may have a closed distal end.
[0006] Preparatory to use, the cuff and transition section are turned inside-out, such that the doubled-over wall of the sleeve at the transition section becomes the distal end of the applicator. The exterior diameter of the doubled-over portion of the wall should be sized to enter comfortably into the vagina. If desired, all or a portion of the sleeve wall may be contoured or of foamed material for patient comfort, but also to shape the vaginal cavity when the applicator is properly positioned within the vagina. In combination with the wall thickness of the sleeve, the mandrel should be sized to expand the outer portion of the doubled over wall to stretch the vagina to the desired contour. As the mandrel is advanced and the cuff is restrained, the sleeve progressively everts until both the (at least) distal portion of the mandrel as well as the inside-out sleeve are positioned within the now distended vagina. The length of the everted applicator sleeve must be adequate to reach the full vaginal depth if that is required for proper delivery of the prescribed dose of radiation. If necessary to facilitate sleeve eversion and dilation of the vagina, lubrication may be applied between the inner and outer portions of the doubled over wall of the sleeve to provide for sliding of the wall portions and the exterior surface of the mandrel, and preferably between the outer sleeve wall and the vaginal wall as well to eliminate any adhesion or friction which might prove uncomfortable. Longitudinal fiber reinforcement may be built into the wall of the sleeve such that advancing the mandrel during eversion against the axial resistance of the cuff or handle results in an increased diameter rather than in any substantial stretching of the sleeve length.
[0007] Once the applicator is positioned within the vagina, a radiation source may be introduced into the mandrel lumen and radiotherapy commenced. If an x-ray source is used, for example a source as described in U.S. Pat. No. 6,319,188, the source may be manipulated through use of a catheter. If an isotope source is used, it may be mounted on a wire as is conventional, and used with an afterloader, for example a GAMMAMED afterloader (Varian Medical Systems, Inc., Charlottesville, Va.). Other source handling methods are known to those of skill in the art and may also be employed.
[0008] Several alternate features are contemplated and result in different embodiments, all of which are within the scope of the invention. As mentioned above, the structure of the applicator may comprise an open or “through” (rather than a closed) mandrel lumen communicating with the lumen of the sleeve, with the sleeve proximal end joined to the mandrel by bonding or mechanical fixation using conventional methods. In another embodiment, the through mandrel lumen may be sized or used for the additional purpose of venting or evacuating the vaginal space as the mandrel is advanced. If the proximal end of the mandrel comprises a conventional hub with a central seal and a secondary access port from outside the patient to the central mandrel lumen is provided, fluids can be withdrawn from the vaginal cavity around the applicator, or therapeutic agents can be administered. Additional lumina may be provided which communicate with other portions of the applicator as necessary to address auxiliary purposes, for example to accommodate wiring for radiation sensors, or to accommodate a plurality of sources or multiple source positions within or on the applicator. Another feature which can be used on the outer (after eversion) sleeve portions of the applicator embodiments presented herein is grooving or texturing, or an open, outer matrix, all suitable for facilitating fluid flow at the vaginal cavity /applicator interface.
[0009] The two portions, mandrel and sleeve, may be one monolithic structure but having different geometry and/or physical properties such that functionality of the applicator is accommodated (more rigid mandrel section and elastomeric or resilient sleeve section). For example, the sleeve portion may be of foamed material (such as foamed urethane) in order to offer a degree of radial compliance at the surface of the vaginal cavity, thus providing for accommodation or formation of different surface contours. As a further variation, the outer diameter of the mandrel and/or the wall thickness of the sleeve portion of the applicator may be varied along their/its length such that preferred, potentially non-uniform outer configurations of the applicator can be provided for therapeutic applications requiring non-uniform absorbed radiation dose prescriptions at different locations within the vagina. Alternatively, this radiation variation can be achieved with radiation-absorbing additives to the sleeve or mandrel or coatings at selected locations.
[0010] In contrast to traditional cylindrical applicators, the applicators of this invention offer easier insertion before dilation, and eliminate axial friction between the applicator and the vaginal wall as the mandrel advances and the applicator is deployed. By expansion of the applicator in the manner described, frictional drag at the vaginal wall is largely eliminated and dilation of the vagina is gradual, gentle and more comfortable for the patient.
DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 depicts in longitudinal section view, an applicator embodiment of the invention comprising sleeve and mandrel portions.
[0012] FIG. 2 depicts in section view, the applicator of FIG. 1 with the distal end turned inside-out.
[0013] FIG. 3 depicts in coronal section view, the applicator introduced into the mouth of the vagina.
[0014] FIG. 4 depicts the applicator as in FIG. 3 , but with the mandrel advanced partially into the vagina causing partial eversion of the sleeve portion of the applicator. An optional obturator is shown within the applicator lumen to be used if a support guide is necessary as the eversion process progresses.
[0015] FIG. 5 a depicts the applicator as in FIG. 4 , but with the mandrel fully advanced and the sleeve further everted. In this figure, the obturator has been removed.
[0016] FIG. 5 b depicts in transverse section, the apparatus of FIG. 5 a at section AA. An optional radiation sensor is shown positioned at the interface between the inverted sleeve and the mandrel.
[0017] FIG. 5 c depicts in transverse section, the apparatus of FIG. 5 a at section AA, showing the outer wall of the everted sleeve with a pattern of grooves in the sleeve surface adjacent the vaginal cavity, and optional longitudinal reinforcing fibers in the sleeve wall.
[0018] FIG. 5 d depicts in longitudinal section view, the distal cuff sleeve wall, but with alternate superelastic Nitinol type of longitudinal reinforcing members having non-uniform thickness along their length.
[0019] FIG. 6 depicts a stress-strain curve for the alternate superelastic Nitinol type of longitudinal reinforcing members for the applicator sleeve.
[0020] FIG. 7 depicts in sagittal section, the applicator fully deployed in the vagina as in FIG. 5 a, and with a radiation source and source catheter positioned within the lumen of the applicator mandrel for delivery of radiation therapy.
[0021] FIG. 8 depicts in section view, a different applicator embodiment of the invention with a closed-end mandrel lumen.
[0022] FIG. 9 a shows in partial section, the everting sleeve wall at the tightly-curved distal extremity of the applicator when reinforced by a thin section of the alternate type of reinforcing member.
[0023] FIG. 9 b shows in partial section, the greater radius of the everting sleeve wall when reinforced by a thick section of the alternate type of reinforcing member.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0024] FIG. 1 shows an applicator 100 of the present invention, comprising a sleeve portion 102 joined at one end, its proximal end 104 , to the distal end of a cylindrical mandrel 110 . The mandrel 110 has a central lumen 112 communicating with a central lumen 106 of the sleeve 102 . Proximate to the distal end 114 of the sleeve 102 , the sleeve increases in diameter to connect with a cuff 116 . The diameter of the cuff is sufficiently great that, together with its structural properties (which might be reinforced, for example by a metal or structural polymer ring 117 seen in FIG. 5 d ), it is prevented from entering the vagina when the applicator 100 is being deployed. If desired, a handle (not shown) can be provided as an alternative to a cuff and the handle will serve equally to prevent entry into the vagina, but will also facilitate manipulation of other elements of the applicator by the therapist during their insertion into the vagina and/or during radiotherapy. Materials of choice for the sleeve 102 must be substantially immune to damage from prescribed radiation, must offer modest elastomeric properties consistent with eversion, and must be amenable to fastening to the mandrel 110 (or offer a range of properties allowing a monolithic structure for the applicator). Suitable materials for the sleeve 102 would include soft silicone elastomers, thermoplastic elastomers like Kraton (Kraton Polymers US, LLC, Houston, Tex.) or thermoplastic rubbers like Santoprene (Exxon Mobil Corp., Akron, Ohio). Mandrel 110 materials should be more robust and would include harder silicone elastomers, polycarbonate, or ethylene-propylene rubber. Harder and softer rubbery materials can be comolded into one integral structure.
[0025] FIG. 2 shows the distal end 114 of the sleeve 102 turned inside out, positioning the cuff 116 adjacent to the cylindrical portion of the sleeve 102 , and the tapered section of the distal end 114 of the sleeve 102 forming a new, doubled-over distal extremity 120 of sleeve 102 . By controlling the geometry and material properties of the sleeve 102 proximate to the distal end 114 , the outer diameter of the distal extremity 120 can be sized for easy insertion into the mouth of the vagina. Positioned as shown in FIG. 3 , the applicator will ease gently into the vagina when deployed, and the cuff 116 will serve to anchor what is now the outer portion of the applicator at the mouth of the vagina 122 . Along the length of the mandrel 110 , depth calibration markings 111 ( FIG. 2 ) can be provided to assist proper depth of insertion of the applicator 100 , as is described later herein.
[0026] FIG. 4 shows the applicator within the vagina 122 after the mandrel 110 has been advanced into the applicator sleeve 102 , continuing eversion of the sleeve and advancing the distal extremity 120 of the applicator 100 within the vagina 122 . If support is necessary to prevent buckling of the sleeve 102 , or to steer the distal extremity 120 as the mandrel 110 is advanced, an obturator 124 may be manipulated within the lumina 106 and 112 to facilitate insertion of the applicator 100 into the vagina 122 . Care must be taken to avoid vaginal injury during manipulation of the obturator. Such an obturator can be made from a structural polymer, for example, polypropylene or polycarbonate.
[0027] FIG. 5 a shows the mandrel 110 fully advanced, and the sleeve 102 further everted, shaping the entire surface of the vaginal cavity into the shape of the outer surface of the applicator 100 . The applicator now fills the entire vaginal cavity, and the obturator (if used) has been removed from the lumen 112 . If the prescription or other factors suggest that the applicator need not or should not be inserted to full depth, the mandrel 110 may be calibrated with markings 111 ( FIG. 2 ) along its length to indicate the depth of insertion into the vagina 122 . Such markings would also serve to provide applicators having variable depth capabilities for differing anatomy. FIG. 5 a shows the outer surface of the applicator 100 being uniform. It can alternatively be contoured in order to provide other, preferred shapes. Such contours would then result from the additive combination of sleeve and mandrel geometries.
[0028] If the contouring sleeve 102 and the mandrel 110 were made to interact in a locking or detent fashion (not shown), this would also serve to prevent the applicator 100 from inadvertently being expelled from the vagina 122 . Should it be desirable to provide an external (to the patient) lock between the sleeve 102 and the mandrel 110 , a series of radial, blind holes or notches (rather than markings) can be provided along the length of the mandrel, and a conventional pawl or pin (not shown) can be provided on the cuff to engage the holes or notches when proper depth has been attained. Alternatively, a series of laterally extending ridges (not shown) can be provided on each surface, for interaction at a series of eversion positions.
[0029] FIG. 5 b is a cross-section view taken at AA in FIG. 5 a and shows the everted sleeve 102 juxtaposed against the outer diameter of the mandrel 110 . In this embodiment, the outer surface of the mandrel 110 is a circular cylinder, and the wall of the sleeve 102 is uniform, resulting in a circular cross-section of the applicator 100 when the sleeve 102 is everted and held open by the mandrel 110 . Note further that the mandrel lumen 112 is shown positioned centrally. In such a circumstance, if a radiation source that emits isotropically, at least in the radial direction transverse to the axis of the mandrel 110 , is positioned within the lumen 112 , the shape of the transverse isodose traces (concentric loci of points of equal dose intensity) will correspond to the circular shape of the applicator. If different isodose traces are desired, the mandrel lumen may be positioned off-center, or the geometry of the mandrel and sleeve may be varied to produce differently shaped isodose traces in the tissues outside of the applicator. The emission characteristics of the radiation source may also be shaped or shielded, and/or the positioning of the source within the mandrel lumen 112 may be varied to create non-circular isodose shapes as well, or non-symmetrical shapes relative to the vagina. (See copending U.S. patent applications Ser. Nos. 11/394,640 and 11/471,277 for descriptions of such methods and apparatus, each of which is hereby referenced and made part of this specification in its entirety.) Rather than sizing the lumen 112 merely to accommodate the radiation source, the lumen may be sized for the additional purpose of venting or evacuating the vaginal space, or for introduction of therapeutic agents as the mandrel is advanced or as radiotherapy progresses. If the lumen 112 is oversize for the source, locator fins (not shown) or other conventional methods of precisely locating the source within the lumen 112 must be provided. In such an embodiment, the proximal end of the mandrel may advantageously further comprise a conventional hub with a central lumen seal (not shown) and a secondary access port from outside the patient to the central lumen for fluid passage. For example, see application Ser. No. 11/481,242, incorporated herein in its entirety. Additional lumina (not shown) may also be provided which communicate with other portions of the applicator to address auxiliary purposes, for example to accommodate wiring for radiation sensors or multiple radiation sources or source positions. FIG. 5 b also shows a radiation sensor 130 , for example of the MOSFET type, positioned on and fastened to the exterior surface of the mandrel. Such a sensor can communicate to outside the body by conventional wiring 132 (shown schematically), or can communicate information to outside the patient by conventional wireless methods. Alternatively, this sensor or other sensors can be positioned and held in place elsewhere on or within elements of the applicator. The purpose of the sensor (or sensors) is to measure the radiation during radiotherapy. Such sensing can be used to control the therapy and/or to verify that prescribed therapy is being or has been administered. Such control may be by manual adjustment, or may be automated—including in real time during a procedure, to alter or verify absorbed dose during or between fractions. (See copending U.S. patent application Ser. No. 11/394,640 for a description of sensing and feedback control of radiotherapy, said patent application being hereby incorporated herein in its entirety.) Once a radiation source has been characterized by multiple sensor mapping to establish output and stability prior to actual therapy, only a few, or as few as one sensor, is necessary to measure radiation source performance.
[0030] FIG. 5 c is a section view of the applicator sleeve 102 , again taken at section AA in FIG. 5 a. FIG. 5 c shows optional grooves 134 in the everted sleeve outer surface for the purpose of facilitating fluid transport between the applicator 100 and the cavity wall 122 of the vagina, such as for the venting of trapped air during placement of the applicator 100 in the vagina, evacuation of seroma, or infusion of therapeutic agents. FIG. 5 c also shows optional longitudinal reinforcing members 126 embedded within the wall of the sleeve 102 . These may advantageously be flexible cords, for example of braided or stranded polyester, molded within the walls during fabrication. Such reinforcement facilitates further eversion of the sleeve 102 as the mandrel 110 is advanced by preventing stretching of the length of the already everted portion of the sleeve wall. Tension tending to produce such stretching is caused by advancing the mandrel against the resistance provided by the cuff 116 . This tension can be reduced by lubrication applied to the sliding surfaces during the eversion process. Such lubrication might for example be a hydrophilic coating applied during applicator fabrication and moistened before insertion into the vagina 122 , or glycerin based lubricants such as KY (Johnson & Johnson, New Jersey) applied before vaginal insertion. An example of a hydrophilic surface coating would be LubriLAST (AST Products, Inc., Billerca, Mass.).
[0031] The longitudinal cord reinforcing members 126 are useful in resisting tension on mandrel insertion. They will follow the bending or rolling action of the everting sleeve wall as the mandrel 110 is advanced. If the compressive rigidity of the sleeve adjacent to the distal end of the mandrel is insufficient to prevent buckling of the sleeve as the mandrel is advanced, different reinforcing members may be necessary.
[0032] As shown in FIG. 5 d, a potentially useful alternative to cord members, and/or use of an obturator (as described in relation to FIG. 4 ) are solid reinforcing members 128 made from superelastic Nitinol. Such members provide buckling resistance under axial compression yet form kink-resistant bends on eversion, straightening out easily if not spontaneously when bending forces are removed. Such behavior is exhibited, for example by ZIPWIRE guidewires (Boston Scientific Corp., Natick, Mass. See also U.S. Pat. Nos. 5,597,378 and 6,245,030 for descriptions of this sort of material).
[0033] FIG. 6 illustrates the stress-strain characteristics of such superelastic material. Upon loading, stress and strain vary linearly, but at a threshold stress, σ T , strain increases greatly without appreciable increase in stress until reaching a strain limit, ε L , whereupon strain will no longer increase without an attendant, significant increase in stress. From the point of this limit strain, ε L , substantially all strain can be recovered upon unloading. This characteristic has important implications in design of the applicator. A reinforcing member 128 exhibiting stress-strain characteristics as in FIG. 6 bends easily until the member's extreme fibers (transverse to the member's neutral axis) reach the limit strain, ε L , which generally happens at one initial point of the bend. In a macro-sense, once ε L is reached at the one initial point, increased resistance to further bending at that point induces adjacent points along the length of the member to reach ε L as well. This behavior progresses until at the limit where all portions of the bend reach ε L concurrently and the shape of the bent member is circular for the entire extent of the bend. The radius of the bent section is proportional to the thickness of the member in the direction transverse to the neutral axis of bending, i.e. in the direction of the radius of curvature. It is therefore clear that, by controlling the thickness of the reinforcing members 128 in the direction described, one may design a sleeve 102 which bends tightly on initial eversion of the distal end 114 of sleeve 102 , as shown in FIG. 3 or FIG. 9 a, but which will later bend only to a larger but uniform radius more proximally as shown in FIGS. 4 or 9 b. As is shown in FIG. 4 , as eversion progresses, the distal extremity 120 of the applicator 100 progresses into the vaginal cavity, and the bend rolls ahead of the mandrel 110 , producing a radially expanding action in keeping with the thickness of the superelastic Nitinol reinforcing members 128 . The trailing portion of the wall of the everted sleeve 102 proximal of the distal extremity 120 will straighten and be supported by the mandrel 110 . The bending radius of the wall of sleeve 102 when reinforced by various thickness of superelastic members 128 is discussed with respect to FIGS. 9 a and 9 b below.
[0034] FIG. 7 shows in sagittal section, the applicator of FIG. 5 a. In this view, the applicator 100 is curved in the medial plane, mimicking the curvature of the anatomy. Use of semi-rigid or flexible mandrel material will permit curved compliance in the manner shown, or alternatively, a more rigid, but curved mandrel can be used to produce the same effect in vagina 122 . FIG. 7 also shows a radiation source 136 mounted at the distal end of a source catheter 138 , positioned in the lumen 112 .
[0035] FIG. 8 shows a similar applicator to that shown in FIG. 7 , but in this Figure, the mandrel lumen 112 is blind, and does not communicate with the distal end 120 of the applicator.
[0036] FIG. 9 a depicts a bend which might be formed in the wall of the sleeve 102 during eversion when reinforced by a thin portion of a reinforcing member 128 . FIG. 9 b depicts a similar section of sleeve wall, but where the thickness of the reinforcing member 128 is thicker, and the radius formed in the everting wall 102 is larger.
[0037] In use, the applicator of this invention can be prepared by applying lubrication (by use of KY gel or wetting any hydrophilic coatings) appropriately if it is anticipated that sliding friction between elements of the applicator, or between the applicator and vagina, could be a problem. Next, the distal end of the applicator (sleeve and cuff or handle) are turned inside out if not already everted during manufacture. The distal extremity is next inserted axially into the mouth of the vagina until the cuff (or handle) rests against the patient's anatomy. The mandrel is then advanced into the sleeve until proper depth for therapy is attained (and the locking mechanism, if provided, is properly engaged). If desired, resistance to the mandrel's 110 insertion may be overcome by holding the cuff (or alternate handle) manually if desired to avoid unnecessary pressure on the patient's anatomy.
[0038] Auxiliary functions can be connected and provided before, during or after applicator insertion as appropriate for convenience and efficacy. These functions would optionally include sensing, venting, suction, and administration of therapeutic agents as prescribed. Insertion of an isotope source into the applicator from an afterloader or similar device for administering radiation would commence after the applicator is positioned, and any auxiliary functions are enabled. If an electronic x-ray source which can be turned on and off at will is to be used, the source can be positioned at any point in the process as convenient, and switched on when the applicator is properly positioned and auxiliary functions are enabled.
[0039] This invention has been described herein in considerable detail in order to instruct one of skill in the art how to practice the invention. It is to be understood, however, that the invention can also be practiced using other methods and apparatus without departing from the scope of the invention itself, as defined in the claims. | An everting applicator for brachytherapy of body cavities such as the vagina has a flexible sleeve secured to a distal mandrel, both the sleeve and the mandrel having internal lumens. The flexible sleeve has a diverging opening at its distal end, preferably bell-shaped or cone-shaped, such that when the open end is pushed against the mouth of a vagina, the sleeve will evert back upon itself, progressively unrolling to an inside out configuration wherein, fully inserted, the sleeve is fully everted back over the exterior surface of the mandrel. A radiation source, isotopic or electronic, is then inserted into the mandrel lumen to commence a therapeutic irradiation procedure of tissues of the vagina. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 587,452, filed June 16, 1975, now abandoned, which in turn is a division of U.S. patent application Ser. No. 480,784, filed June 19, 1974, now U.S. Pat. No. 3,923,792, issued Dec. 2, 1975.
BRIEF SUMMARY OF THE INVENTION
The invention relates to compounds of the formula ##STR1## wherein R 1 is lower alkyl, cyclo-lower alkyl or cyclo-lower alkyl-lower alkyl; R 2 is hydrogen or lower alkyl; provided that when R 1 is lower alkyl, then R 2 must be lower alkyl;
And salts thereof with pharmaceutically acceptable bases. The compounds of formula I are useful as antibacterial agents.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to compounds of the formula ##STR2## wherein R 1 is lower alkyl, cyclo-lower alkyl or cyclo-lower alkyl-lower alkyl; R 2 is hydrogen or lower alkyl; provided that when R 1 is lower alkyl, then R 2 must be lower alkyl;
And salts thereof with pharmaceutically acceptable bases.
As used herein, the term "lower alkyl" denotes a straight or branched chain saturated hydrocarbon of 1-7 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, neopentyl, pentyl, heptyl, and the like; methyl is preferred. The term "cyclo-lower alkyl" denotes a cyclic hydrocarbon of 3-8 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and the like. The term "cyclo-lower alkyl-lower alkyl" denotes a lower alkyl group as defined above wherein a hydrogen atom is substituted by a cyclo-lower alkyl group as defined above. The term "alkanoyl" denotes a group derived from an aliphatic carboxylic acid of 1-7 carbon atoms, for example, formyl, acetyl, propionyl, and the like.
The compounds of the invention are prepared by reacting a compound of the formula ##STR3## wherein R 1 and R 2 are as hereinbefore described, with a compound of the formula ##STR4## wherein R 7 is alkanoyl, and X is chlorine, bromine or iodine, preferably chlorine.
Compounds of formula I, wherein R 2 is hydrogen and R 1 is cyclo-lower alkyl or cyclo-lower alkyl-lower alkyl are a preferred group of compounds. Preferred compounds of formula I are:
N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)-sulfanilamide;
N 1 -(1-cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)-sulfanilamide and the like.
A most preferred compound of formula I of the invention is N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide.
The compounds of formula I form pharmaceutically acceptable acid addition salts with bases. Such bases include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide or the like; or amines such as dicyclohexylamine ethylamine, ethanolamine or the like.
The starting materials of formula II are prepared according to the procedures described in the Examples. Exemplary of the compounds of formula II are:
1-cyclopropylmethylcytosine (also known as 1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-aminopyrimidine);
1-cyclopentylcytosine (also known as 1-cyclopentyl-1,2-dihydro-2-oxo-4-aminopyrimidine);
1-cyclopropylcytosine (also known as 1-cyclopropyl-1,2-dihydro-2-oxo-4-aminopyrimidine);
1-cyclohexylcytosine (also known as 1-cyclohexyl-1,2-dihydro-2-oxo-4-aminopyrimidine);
1-cyclohexyl-5-methylcytosine (also known as 1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-aminopyrimidine);
1-ethyl-5-methylcytosine (also known as 1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-aminopyrimidine);
1-cyclopropyl-5-methylcytosine (also known as 1-cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-aminopyrimidine); or the like.
A cytosine of formula II is conveniently reacted with a sulfanilyl chloride, -bromide, or -iodide, preferably the -chloride of formula III in the presence of a base, for example, pyridine, or a trialkylamine such as triethylamine or trimethylamine, with or without an inert organic solvent such as acetonitrile or the like. The reaction temperature is not critical; preferably, the reaction is carried out at room temperature. The resulting product of formula I can be recovered utilizing conventional procedures, for instance, by crystallization or the like. The N 4 -alkanoyl derivative of formula I, as described in the Examples, can be deacylated according to known procedures. For example, the alkanoyl derivative is treated with an alkali metal hydroxide such as sodium hydroxide. The deacylation is preferably carried out at an elevated temperature, for example, at a temperature in the range of from about 25° to 100° C. The reaction product, which is a compound of formula I, can be recovered utilizing conventional procedures, for example, crystallization or the like.
The compounds of formula III are known compounds or can be prepared in accordance with known procedures. Exemplary of such compounds are:
N-acetylsulfanilyl chloride;
N-acetylsulfanilyl bromide;
or the like.
The compounds of formula I and its pharmaceutically acceptable salts with bases are usesul as antibacterial agents, e.g., against S. aureus Smith, S. pyogenes 4, P. vulgaris 190 and S. typhosa P58a. The antibacterial activity of the claimed compounds can be demonstrated in warm-blooded animals, for exmaple, in Swiss albino mice weighing 18 to 20 gms. The mice are infected intraperitoneally with 0.5 ml. of an inoculum containing 100 to 1000 minimal lethal doses of the organism prepared in 5% hog gastric mucin, except for S. pyogenes 4 which is suspended papain digested bacto beef broth. The infecting inocule are prepared from overnight broth cultures. The test substance is administered orally as follows: two treatments, 5 hours apart, on the day of and day following infection, and one treatment on the second and third days following infection. Mice which die are autopsied and cultures are taken from heart blood, the survivors are observed for a period of 2 weeks.
For such use, the presently disclosed compounds are formulated, using conventional inert pharmaceutical adjuvant materials, into dosage forms which are suitable for oral or parenteral administration. Such dosage forms include tablets, suspensions, solutions, etc. Furthermore, the compounds of this invention can be embodied into, and administered in the form of, suitable hard or soft capsules. The identity of the inert adjuvant materials which are used in formulating the present compounds into oral and parenteral dosage forms will be immediately apparent to persons skilled in the art. These adjuvant materials, either inorganic or organic in nature, include, for example, water, gelatin, lactose, starch, magnesium stearate, talc, vegetable oils, gums, polyalkyleneglycols, etc. Moreover, preservatives, stabilizers, wetting agents, emulsifying agents, salts for altering osmotic pressure, buffers, etc. can be incorporated, if desired, into such formulations.
The quantity of active medicament which is present in any of the abovedescribed dosage forms is variable. It is preferred, however, to provide capsules or tablets containing from about 100 mg. to about 500 mg. of the formula I base or an equivalent amount of a medicinally acceptable base addition salt thereof.
The frequency with which any such dosage form will be administered to a patient or a host, i.e. a warm-blooded animal, will vary, depending upon the quantity of active medicament present therein and the needs and requirements of the patient, as diagnosed by the prescribing physician. Under ordinary circumstances, however, up to about 80 mg/kg. of the compound can be administered daily in several dosages. It is to be understood, however, that the dosages set forth therein are exemplary only and that they do not, to any extent, limit the scope or practice of this invention.
The sulfacytosine derivatives of the invention can also be used in combination with known potentiators of the 2,4-diamino-5-benzylpyrimiding type having the formula ##STR5## wherein R 3 is hydrogen or lower alkyl, R 4 is hydrogen or lower alkoxy, R 5 is amino, lower alkylamino, di-lower alkylamino or lower alkoxy, and R 6 is lower alkoxy, provided that when R 3 is lower alkyl, R 4 is hydrogen and R 5 is lower alkoxy,
or pharmaceutically acceptable acid addition salts thereof.
The potentiators of formula IV above may be prepared by chlorinating or brominating a compound of the formula ##STR6## wherein R 3 , R 4 , R 5 and R 6 are as defined in formula IV above, and treating the halo compound obtained with ammonia.
The reaction with ammonia is preferably carried out using a lower alkanol as solvent, preferably methanol. A suitable temperature range is from about 80° C. to about 200° C., preferably from about 100° C. to about 150° C. Since said temperature range is above the boiling point of methanol, the reaction is performed in a "closed system", e.g., in an autoclave. The chlorinating or brominating step as the case may be, is performed in the usual manner as known to all persons skilled in the art.
The potentiators of formula IV above may be transformed into pharmaceutically acceptable acid addition salts by contacting these compounds with suitable acids. Examples of suitable acids are hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, malonic acid, succinic acid, maleic acid, citric acid, tartaric acid, malic acid, fumaric acid, methane sulfonic acid, or p-toluenesulfonic acid, etc.
Compositions comprising sulfacytosine derivatives and potentiators are prepared by mixing the components, whereby the sulfonamide and the potentiator may be present in a weight by weight ratio of from about 1:1 to about 40:1, preferably about 5:1. The mixing of the components may be performed in a known manner. These compositions are useful as antibacterial agents and are administered and used in the same manner as described hereinbefore for the compounds of formula I.
Preferred compounds of formula IV are:
2,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine;
2,4-diamino-5(4-amino-3,5-dimethoxybenzyl)-pyrimidine; and
2,4-diamino-5-(2-methyl-4,5-dimethoxybenzyl)-pyrimidine.
The following Examples further illustrate the invention. All temperatures are in degrees Centrigrade, unless otherwise mentioned.
EXAMPLE 1
Preparation of 3-cyclopropylmethylaminopropionitrile
With stirring and cooling in ice to maintain a reaction temperature of 8-10°, 16.4 g. of acrylonitrile was added to 22 g. of aminomethylcyclopropane. The mixture was allowed to warm to room temperature, with intermittent cooling for about 1 hour to maintain the temperature below 25°, and then allowed to stand overnight. The mixture was heated for 1 hour on a steam bath and then distilled under reduced pressure to obtain 32.0 g. of 3-cyclopropylmethylaminopropionitrile, boiling at 101°-102° at 7 mm.
EXAMPLE 2
Preparation of a mixture of 1-(2-cyanoethyl)-1-cyclopropylmethylurea and 1-cyclopropylmethyl-5,6-dihydrocytosine
With cooling in ice to maintain the reaction at 25°-30°, 19.1 ml. of concentrated hydrochloric acid was added to 29.8 g. of 3-cyclopropylmethylaminopropionitrile to adjust the pH to 6.50. A total of 20.1 g. of 97% potassium cyanate was then added in four equal portions at 1 hour intervals. After the first portion was added, the reaction mixture was heated to 50° and maintained at 48°-50° with stirring overnight. The mixture was evaporated under reduced pressure with heating on a steam bath. The mixture was twice more evaporated to dryness after addition of 25 ml. portions of benzene. The residue was boiled for five minutes with 50 ml. of isopropanol, and the insoluble portion filtered off from the hot mixture and washed with an additional 10 ml. of hot isopropanol. The combined filtrate and wash was cooled in ice and allowed to crystallize for 2 hours before filtering the mixture of 1-(2-cyanoethyl)-1-cyclopropylmethylurea and 1-(cyclopropylmethyl-5,6-dihydrocytosine and washing with cold isopropanol; yield 28.9 g., m.p. 76°-100°. This product showed two spots, at R f 's of 0.54 and 0.92 (1:1 methanol-chloroform on Silica gel) when visualized in an iodine chamber. The mixture was used directly for the preparation of 5-bromo-1-cyclopropylmethyl-5,6-dihydrocytosine.
EXAMPLE 3
Preparation of 1-(2-cyanoethyl)-1-cyclopropylmethylurea
This compound was isolated from the mixture of Example 2 by two recrystallizations from ethanol. This product, which corresponded to the spot at higher R f 's on Tlc, melted at 84°-87°.
Analysis Calcd. for: C 8 H 13 N 3 O: C, 57.47; H, 7.84; N, 25.13; Found: C, 57.44; H, 8.01; N, 25.18.
EXAMPLE 4
Preparation of 1-cyclopropylmethyl-5,6-dihydrocytosine
0.84 g. of the mixture of products obtained in Example 2 was refluxed for 45 minutes in 8 ml. of ethanol containing 0.10 g. of sodium methoxide. On cooling in ice, 0.50 g. of crystalline product separated, corresponding on Tlc to the spot of lower R f . After recrystallization from ethanol, the obtained 1-cyclopropylmethyl-5,6-dihydrocytosine melted at 213°-214°.
Analysis Calcd. for C 8 H 13 N 3 O: C, 57.47; H, 7.84; N, 25.13; Found: C, 57.28H, 7.89; N, 25.30.
EXAMPLE 5
Preparation of 5-bromo-1-cyclopropylmethyl-5,6-dihydrocytosine
To a solution of 8.10 g. of sodium methoxide in 150 ml. of methanol was added 25.0 g. of the mixture of 1-cyanoethyl-1-cyclopropylmethylurea and 1-cyclopropylmethyl-5,6-dihydrocytosine obtained in Example 2. The mixture was refluxed for 45 minutes, and then cooled in ice, whereupon crystallization occurred. With stirring and cooling to maintain the reaction at 3°-5°, 24.0 g. of bromine was added over a period of 20 minutes. The precipitate redissolved during this addition. The mixture was allowed to warm to room temperature and to stand for three days, during which time crystallization occurred. After chilling in ice, the resulting 5-bromo-1-cyclopropylmethyl-5,6-dihydrocytosine was filtered, washed with cold methanol, and dried in a vacuum desiccator over potassium hydroxide; yield 31.1 g., m.p. 139°-143° with resolidification. Recrystallization of 30.1 g. of product, from 21. of methanol, yielded 17.1 g. of 5-bromo-1-cyclopropylmethyl-5,6-dihydrocytosine melting at 143°-145° with resolidification.
Analysis Calcd. for C 8 H 12 BrN 3 O: C, 39.04; H, 4.91; N, 17.07; Found: C, 38.91; H, 4.95; N, 17.03.
EXAMPLE 6
Preparation of 1-cyclopropylmethylcytosine
To a solution of 4.55 g. of 85% potassium hydroxide in 93 mml. of methanol cooled to 5°, was added 17.0 g. of 5-bromo-1-cyclopropylmethyl-5,6-dihydrocytosine. The mixture was stirred and allowed to warm spontaneously. When the initial reaction, which had warmed the mixture to 30°, subsided, the mixture was refluxed for 5 minutes and allowed to cool and stand at room temperature overnight. The suspension was evaporated under reduced pressure on a water bath at 86°. The residue was triturated was 300 ml. of water on a steam bath and chilled in ice before filtering. The resulting 1-cyclopropylmethylcytosine was washed with cold water and dried in a vacuum desiccator over potassium hydroxide; yield, 9.50 g., m.p. 264°-266°. A sample for analysis was recrystallized from ethanol; m.p. 265°-267°.
Analysis Calcd. for C 8 H 11 N 3 O: C, 58.17; H, 6.71; N, 25.44; Found: C, 58.23; H, 6.39; N, 25.72.
EXAMPLE 7
Preparation of N 4 -Acetyl-N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide
A. A mixture of 7.60 g. of 1-cyclopropylmethylcytosine, 10.8 g. of N-acetylsulfanilyl chloride and 30 ml. of pyridine was stirred overnight. The mixture was diluted slowly with 300 ml. of water and acidified by addition of 50 ml. of 6N hydrochloric acid. The mixture was allowed to stand for 5 hours to complete the crystallization, before filtering and washing with water; yield 13.5 g. of N 4 -acetyl-N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 218°-223°.
B. A mixture of 495 mg. of 1-cyclopropylmethylcytosine, 702 mg. of N-acetylsulfanilyl chloride, 10 ml. of acetonitrile and 322 mg. of triethylamine was stirred and refluxed for 18 hours. The solvent was evaporated under reduced pressure, and the residue triturated with 10 ml. of water and 3 ml. of 10% aqueous sodium hydroxide. The alkaline solution was decanted from the dark insoluble portion and cleared by filtration. Addition of acetic acid to about pH 5 gave a gummy precipitate which solidified only very slowly. The aqueous solution was decanted and the gum triturated with 2 ml. of hot ethanol, and allowed to settle in an ice bath to obtain after filtration 280 mg. of product, melting at 222°-224°. A sample for analysis was recrystallized from aqueous ethanol; m.p. 225°-226°.
Analysis Calcd. for C 16 H 18 N 4 O 4 S: C, 53.03; H, 5.00; N, 15.46; Found: C, 52.94; H, 5.09; N, 15.32.
EXAMPLE 8
Preparation of N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide
A mixture of 14.6 g. of N 4 -acetyl-N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide and 146 ml. of 10% aqueous sodium hydroxide was heated on a steam bath for 1 hour after the temperature reached 85°. After dilution with 300 ml. of water, the mixture was filtered and acidified to about pH 5 by gradual addition of acetic acid. The initially gummy precipitate quickly solidified. The lumpy solid was crushed, filtered, washed with water, and dried in a vacuum desiccator over potassium hydroxide to yield 10.4 g. of N 1 -(1-cyclopropylmethyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 87°-95°. Recrystallization of 10.0 g. of this product from 60 ml. of 50% ethanol and drying in a vacuum desiccator over potassium hydroxide gave hydrated crystals which required further drying at 60° under reduced pressure, yield 8.03 g., m.p. 90°-92°.
Analysis Calcd. for C 14 H 16 N 4 O 3 S: C, 52.49; H, 5.03; N, 17.49; Found: C, 52.24; H, 5.18; N, 17.32.
EXAMPLE 9
Preparation of 3-cyclopentylaminopropionitrile
With stirring and cooling in an ice bath to control the temperature at 10°-15°, 36.4 g. of acrylonitrile was added to 58.4 g. of cyclopentylamine over a period of 20 minutes. The mixture was allowed to warm spontaneously to 30°, and then cooled intermittently for about 30 minutes, until the reaction subsided. After standing overnight, the mixture was heated for 1 hour on a steam bath and distilled under reduced pressure to yield 82.4 g. of 3-cyclopentylaminopropionitrile, b.p. 113°-115° at 9 mm.
EXAMPLE 10
Preparation of 1-(2-cyanoethyl)-1-cyclopentylurea
With stirring and cooling to maintain a reaction temperature of 25°-30°, 45.5 ml. concentrated hydrochloric acid was added to 76.0 g. of 3-cyclopentylaminopropionitrile to obtain a final pH of 6.50. A total of 46.0 g. of 97% potassium cyanate was then added in four equal portions at 1-hour intervals. After the first portion was added, the reaction was heated to 50° and maintained at 48°-50° with stirring overnight. The mixture was evaporated under reduced pressure with heating on a steam bath. The mixture was twice more evaporated to dryness after the addition of 80 ml. portions of benzene. The residue was triturated with 120 ml. of boiling isopropanol. The potassium chloride was removed by filtration and washed with 20 ml. of hot isopropanol, and the filtrate allowed to crystallize in an ice bath to yield 65 g. of 1-(2-cyanoethyl)-1-cyclopentylurea, m.p. 81°-84°.
EXAMPLE 11
Preparation of 5-bromo-1-cyclopentyl-5,6-dihydrocytosine
To a solution of 17.8 g. of sodium methoxide in 330 ml. of methanol was added 59.7 g. of 1-cyanoethyl-1-cyclopentylurea. The mixture was stirred and heated on a steam bath for 30 minutes and then cooled in ice. At 5°-8°, 52.9 g. of bromine was added over a period of 30 minutes. The ice bath was removed. Thereafter, the mixture was allowed to warm to room temperature and stand for 3 days, during which time crystallization occurred. The mixture was chilled in ice before filtering the product, which was washed with cold methanol and then with ether to yield 69.8 g. of 5-bromo-1-cyclopentyl-5,6-dihydrocytosine, m.p. 134°-144° with resolidification.
EXAMPLE 12
Preparation of 1-cyclopentylcytosine
To a solution of 15.8 g. of 85% KOH in 320 ml. of methanol was added at 10°, 62.4 g. of 5-bromo-1-cyclopentyl-5,6-dihydrocytosine. The mixture was stirred and allowed to warm spontaneously to a maximum temperature of 31° after 15 minutes. When the initial reaction subsided, the mixture was refluxed on a steam bath for five minutes. After standing overnight at room temperature, the mixture was evaporated to dryness under reduced pressure. The residue was dissolved in 100 ml. of water by heating quickly to 80° on a steam bath, and the solution filtered through a sintered glass funnel before cooling in ice to 30°. The product was allowed to crystallize at room temperature for 2 hours before filtering to yield 38.8 g. of 1-cyclopentylcytosine, m.p. 183°-198°. The product was used directly in the subsequent reaction with N-acetylsulfanilyl chloride.
A sample for analysis was prepared by purification via the hydrochloride, as follows: The 1-cyclopentylcytosine (10.0 g.) was dissolved in 40 ml. of warm ethanol, and the mixture strongly acidified by addition of ethanolic HCl. The hot solution was cleared by filtration and allowed to crystallize at room temperature to yield 6.07 g. of 1-cyclopentylcytosine hydrochloride, m.p. 204°-209°. A solution of 5.30 g. of the hydrochloride in 10 ml. of hot water was made strongly alkaline by addition of excess 10% aqueous sodium hydroxide solution, which was allowed to crystallize at room temperature to yield 3.75 g. of 1-cyclopentylcytosine, m.p. 229°-233°.
Analysis Calcd. for C 9 H 13 N 3 O: C, 60.32; H, 7.31; N, 23.45; Found: C, 60.19; H, 7.57; N, 23.64.
EXAMPLE 13
Preparation of N 4 -Acetyl-N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide
A mixture of 240 g. of 1-cyclopentylcytosine, 31.4 g. of N-acetylsulfanilyl chloride and 80 ml. of pyridine was stirred after controlling the initial reaction by momentary cooling to keep the reaction temperature below 35°. The mixture was diluted with 800 ml. of water and acidified to pH 1-2 by the addition of 148 ml. of 6N hydrochloric acid. After 4 hours, the supernatant liquid was decanted from the viscous gummy precipitate. The gum was dissolved in 100 ml. of warm ethanol and 100 ml. of water was added. The mixture was stirred for 3 hours as crystallization occurred to yield 26.3 g. of N 4 -acetyl-N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 219°-228°. The decantate from the initially viscous gummy precipitate also deposited crystals of N 4 -acetyl-N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide during 3 hours; additional yield 2.80 g., m.p. 230°-234°.
EXAMPLE 14
Preparation of N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide
A mixture of 29.1 g. of N 4 -acetyl-N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide and 290 ml. of 10% aqueous sodium hydroxide was heated on a steam bath for 1 hour, diluted with 290 ml. of tap water, and acidified by addition of 60 ml. of acetic acid. The initially oily precipitate solidified over a period of several hours to yield 21.1 g. of product melting over a wide range. The resulting product was dissolved in 200 ml. of boiling methanol. treated with charcoal, and the filtered solution evaporated under reduced pressure to a volume of 65 ml., which crystallized at room temperature to yield 15.2 g. of N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 167°-171°. The product was dissolved in 150 ml. of methanol. The volume was reduced to 60 ml. by evaporation under reduced pressure, and the product allowed to crystallize at room temperature to yield 12.7 g. of N 1 -(1-cyclopentyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 168°-171°.
Analysis Calcd. for C 15 H 18 N 4 O 3 S: C, 53.88; H, 5.43; N, 16.76; Found: C, 53.78; H, 5.23; N, 16.62.
EXAMPLE 15
Preparation of 3-cyclopropylaminopropionitrile
With stirring and cooling to maintain a reaction temperature of 10°-15°, 46.5 g. of acrylonitrile was added to 50.0 g. of cyclopropylamine. When the addition was complete, the reaction mixture was allowed to warm spontaneously to a maximum temperature of 30°, and then allowed to stand overnight at room temperature. After heating 1 hour on a steam bath and distillation under reduced pressure, 64.8 g. of 3-cyclopropylaminopropionitrile, b.p. 90°-92° at 12 mm., was obtained.
EXAMPLE 16
Preparation of 1-(2-cyanoethyl)-1-cyclopropylurea
With stirring and cooling in ice, 46 ml. of concentrated hydrochloric acid was added to 64.8 g. of 3-cyclopropylaminopropionitrile at 25°-30° to obtain a final pH of 6.00. A total of 49.3 g. of 97% potassium cyanate was then added in four portions at intervals of 1 hour. After the first portion was added, the mixture was warmed to 50° and maintained at 45°-50° with stirring overnight. The mixture was evaporated to dryness under reduced pressure with warming on a steam bath. After the addition of 100 ml. of benzene, the mixture was again evaporated to dryness. The residue was extracted by trituration with a total of 600 ml. of boiling isopropanol in two portions, and the filtered solution allowed to crystallize in an ice bath to yield 55.3 g. of 1-(2-cyanoethyl)-1-cyclopropylurea, m.p. 119°-123°.
EXAMPLE 17
Preparation of 5-bromo-1-cyclopropyl-5,6-dihydrocytosine
To a solution of 17.8 g. of sodium methoxide in 330 ml. of methanol was added 50.5 g. of 1-(2-cyanoethyl)-1-cyclopropylurea. The mixture was refluxed for 30 minutes, and cooled in ice. With stirring at 4°-6°, 52.9 g. of bromine was added over a period of 30 minutes. The mixture, containing some precipitate, was stirred overnight. After approximately 24 hours, a mild exothermic reaction was noted. As the original precipitate suddenly dissolved, a precipitate of white crystals began to separate. The mixture was allowed to stand for three days before filtering, whereby 55.9 g. of 5-bromo-2-cyclopropyl-5,6-dihydrocytosine, m.p. 135°-140° with resolidification, was obtained.
EXAMPLE 18
Preparation of 1-cyclopropylcytosine
To a solution of 15.2 g. of 85% potassium hydroxide in 310 ml. of methanol was added 53.3 g. of 5-bromo-1-cyclopropyl-5,6-dihydrocytosine. The mixture was allowed to warm spontaneously for 30 minutes and then refluxed with stirring for 5 minutes. The mixture was stirred for 1.5 hours, allowed to stand overnight, and evaporated under reduced pressure. The residue was dissolved in 80 ml. of water at 80°, and the solution after filtration was allowed to crystallize overnight in a refrigerator. The crystallized material was washed with ice-cold water and then with ether to yield 20.4 g. of 1-cyclopropylcytosine, m.p. 209°-223°.
EXAMPLE 19
Preparation of N 4 -Acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide
A mixture of 10.6 g. of 1-cyclopropylcytosine, 16.4 g. of N-acetylsulfanilyl chloride and 47 ml. of pyridine was stirred overnight after momentary cooling to maintain the reaction below 30°. The mixture was poured into 700 ml. of water, and after filtration by gravity, the solution was strongly acidified by addition of 6N hydrochloric acid. Gradual crystallization occurred overnight in a refrigerator before filtering the N 4 -acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)-sulfanilamide; yield 10.7 g., m.p. 139°-143°.
EXAMPLE 20
Preparation of N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide
A solution of 10.7 g. of N 4 -acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide in 107 ml. of 10% aqueous sodium hydroxide was heated on a steam bath for 1 hour. After cooling below 35°, 15 ml. of acetic acid was added to precipitate a gum, which quickly solidified; yield 7.45 g., m.p. 119°-123°. Of this period, 7.35 g. was dissolved in 735 ml. of hot water by adding 12 ml. of 10% aqueous sodium hydroxide to obtain a strongly alkaline solution. After the addition of 5 ml. of acetic acid, the hot solution was immediately filtered and allowed to crystallize at room temperature to yield 5.95 g. of N 1 -(1-cyclopropyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 124°-126°.
The sample for analysis, after recrystallization from 80% ethanol, was found to contain water of crystallization.
Analysis Calcd. for C 13 H 14 N 4 O 3 S.H 2 O: C, 48.15; H, 4.97; N, 17.28; H 2 O; 5.55; Found: C, 48.01; H, 4.81; N, 17.19; H 2 O; 5.96.
EXAMPLE 21
Preparation of 3-cyclohexylaminopropionitrile
With stirring and intermittent cooling to maintain the reaction at 20°-25°, 53.0 g. of acrylonitrile was added over a 30-minute period to 99.0 g. of cyclohexylamine. Intermittent cooling was continued for another hour until the reaction subsided, and the mixture was allowed to stand overnight before distillation under reduced pressure to yield 109 g. of 3-cyclohexylaminopropionitrile, b.p. 75°-78° at 0.1 mm.
EXAMPLE 22
Preparation of 1-(2-cyanoethyl)-1-cyclohexylurea
With stirring and cooling in ice to maintain the reaction temperature below 35°, 57.8 ml. of concentrated hydrochloric acid and 40 ml. of water were added to 106.6 g. of 3-cyclohexylaminopropionitrile, followed by about 3 ml. of 10% aqueous sodium hydroxide to bring the final pH to 6.00. A total of 58.5 g. of 97% potassium cyanate was then added in four equal portions at one -hour intervals. After the first addition, the mixture was warmed to 50° and maintained at 45°-50° during the remainder of the reaction time. An additional 75 ml. of water was added when a thick precipitate separated, and stirring was continued overnight. The mixture was heated to 80° after adding 200 ml. of water, and then cooled to room temperature and filtered to yield 121 g. of 1-(2-cyanoethyl)-1-cyclohexylurea, m.p. 110°-112°.
EXAMPLE 23
Preparation of 5-bromo-1-cyclohexyl-5,6-dihydrocytosine
To a stirred solution of 27.0 g. of sodium methoxide in 500 ml. of methanol was added 97.5 g. of 1-(2-cyanoethyl)-1-cyclohexylurea. The mixture was refluxed for 30 minutes, cooled to 5°, and 80 g. of bromine was added at 5°-10° over a period of 30 minutes. The mixture was stirred at ambient temperature overnight, and the precipitate filtered and washed with methanol to yield 118.4 g. of 5-bromo-1-cyclohexyl-5,6-dihydrocytosine, m.p. 152°-156° with resolidification.
EXAMPLE 24
Preparation of 1-cyclohexylcytosine
To a stirred solution of 27.7 g. of 85% potassium hydroxide in 570 ml. of methanol at 10° was added 115 g. of 5-bromo-1-cyclohexyl-5,6-dihydrocytosine. The mixture was allowed to warm spontaneously, reaching a maximum temperature of 33° after 13 minutes. After about 1 hour, the mixture was refluxed for 5 minutes and allowed to cool to room temperature with continued stirring for 2 hours. After standing overnight, the mixture was evaporated under reduced pressure. The residue was triturated with 500 ml. of water at 75° for 5 minutes and allowed to settle for 2 hours with cooling in ice to yield 70.7 g. of a product, m.p. 213°-231°. Of this product, 65.0 g. was recrystallized from 375 ml. of methanol to yield 42.7 g. of 1-cyclohexylcytosine, m.p. 252°-258°.
EXAMPLE 25
Preparation of N 4 -Acetyl-N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl) sulfanilamide
A mixture of 29.0 g. of 1-cyclohexylcytosine, 90 ml. of pyridine and 35.1 g. of N-acetylsulfanilyl chloride was stirred overnight, poured into 900 ml. of water, and acidified by addition of 80 ml. of concentrated hydrochloric acid. After several hours of vigorous stirring, the precipitated product solidified to yield 33.3 g. of N 4 -acetyl-N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl-sulfanilamide, m.p. 219°-234°. A sample purified by two recrystallizations from ethanol melted at 247°-250°.
EXAMPLE 26
Preparation of N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide
A mixture of 27.9 g. of N 4 -acetyl-N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide and 280 ml. of 10% aqueous sodium hydroxide was stirred and heated on a steam bath for 1 hour, diluted with 280 ml. of water, cooled to room temperature, and acidified by dropwise addition of 56 ml. of acetic acid to precipitate a finely divided solid to yield 21.4 g. of crude N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 100°-120°.
Dicyclohexylamine Salt
Of the product, 20.0 g. was dissolved in 120 ml. of hot ethanol and 11.5 g. of dicyclohexylamine was added. The hot solution was filtered quickly and then crystallization was allowed to proceed first at room temperature and then in a refrigerator overnight to yield 15.8 g. of the dicyclohexylamine salt of N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 126°-128°. A sample for analysis was recrystallized from ethanol; it contained ethanol of crystallization.
Analysis Calcd. for C 30 H 29 N 5 O 4 S (C 16 H 20 N 4 O 3 S . C 12 H 23 N . C 2 H 6 O) C, 62.58; H, 8.58; N, 12.16; Found: C, 62.34; H, 8.54; N, 12.23.
Of the above dicyclohexylamine salt, 15.5 g. was stirred with 300 ml. of water, 75 ml. of 10% aqueous sodium hydroxide and 250 ml. of ether. The ether was separated, and the aqueous phase washed again with 250 ml. of ether. The aqueous solution was diluted and 1200 ml. of water, heated to 90°, quickly acidified with 15 ml. of acetic acid, and allowed to stand three days before filtering the precipitate to yield 8.50 g. of N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 153°-156°. This product was dissolved in 60 ml. of hot methanol, and the solution filtered and boiled down to a volume of 25 ml. before allowing to stand and crystallize overnight to yield 7.10 g. of N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide, m.p. 155°-157°.
Analysis Calcd. for C 16 H 20 N 4 O 3 S: C, 55.16; H, 5.79; N, 16.08; Found: C, 54.94; H, 5.82; N, 16.36.
EXAMPLE 27
Preparation of 1-cyclohexyl-4-thiothymine
A solution of 8.20 g. of 1-cyclohexythymine 1 and 9.60 g. of phosphorous pentasulfide in 500 ml. of pyridine was refluxed for 9 hours, and the solvent distilled off under reduced pressure. The residue was triturated with 120 ml. of water to obtain a solid, which was dried in the air and recrystallized from 120 ml. of ethanol to yield 7.15 g. of 1-cyclohexyl-4-thiothymine, melting at 176°-179°.
1 T. Okano, S. Goya and T. Takahashi, J. Pharm. Soc. Japan, 88, 1112 (1968).
A 300 mg. sample of product prepared as above was recrystallized from 6 ml. of ethanol to obtain 224 mg. of analytically pure 1-cyclohexyl-4-thiothymine, melting at 177°-178°.
EXAMPLE 28
Preparation of 1-cyclohexyl-5-methylcytosine
5.0 g. of 1-cyclohexyl-4-thiothymine was added to 120 ml. of ethanol which had been saturated with ammonia at 5°. The solution was heated under pressure at 120° for 22 hours. After removal from the pressure reactor, the mixture was reheated, filtered and concentrated by evaporation under reduced pressure to a volume of 60 ml. The solution was chilled in ice to obtain 3.28 g. of crystalline product. On further concentration, the mother liquor yielded a second crop of 0.69 g. The combined crops, which contained ethanol of crystallization, were distilled with 100 ml. of toluene until approximately 50 ml. of distillate was collected. The residue was chilled in ice to obtain 2.65 g. of 1-cyclohexyl-5-methylcytosine, melting at 205°-207°.
EXAMPLE 29
Preparation of N 4 -acetyl-N 1 -(1l -cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide
A mixture of 2.07 g. of 1-cyclohexyl-5-methylcytosine, 10 ml. of pyridine and 2.34 g. of N-acetylsulfanilyl chloride was stirred overnight, poured into 100 ml. of cold water, and acidified by addition of 18 ml. of 6N hydrochloric acid. Supernatant liquid was decanted from the gummy precipitate, which was washed with water, by decantation. The gum solidified on trituration with 10 ml. of ethanol to yield 1.75 g. of N 4 -acetyl-N 1 -(1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide, melting at 254°-256°. The product may be crystallized from ethanol.
EXAMPLE 30
Preparation of N 1 -(1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl) sulfanilamide
A mixture of 169 mg. of N 4 -acetyl-N 1 -(1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide and 1.7 ml. of 10% aqueous sodium hydroxide was heated on the steam bath for 30 minutes, diluted with an equal volume of water, and heated for another 30 minutes. The mixture was cooled and acidified by dropwise addition of acetic acid, diluted with 1 ml. of water and allowed to stand for 30 minutes before filtering. Of the crude product obtained (123 mg.), 94 mg. was dissolved in 2 ml. of warm methanol, and crystallized by evaporating to one-quarter volume in a stream of nitrogen, to obtain 48.9 mg. of N 1 -(1-cyclohexyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide, melting point 203°-206°.
EXAMPLE 31
Preparation of 1-ethyl-4-thiothymine
A mixture of 4.62 g. of 1-ethylthymine 2 , 7.33 g. of phosphorus pentasulfide and 100 ml. of pyridine was refluxed for 8.5 hours. The pyridine was distilled off under reduced pressure, and the residue triturated with 50 ml. of water to obtain a solid, which was filtered and washed with four 10 ml. portions of water. After drying in the air, this material was crystallized from 100 ml. of ethanol to obtain 4.00 g. of 1-ethyl-4-thiothymine, melting at 204°-207°.
2 K. Yamauchi and M. Kinoshita, J. Chem. Soc. Perkin I, 1973, 391.
A 300 mg. sample was recrystallized from 10 ml. of ethanol to obtain 219 mg. of 1-ethyl-4-thiothymine, melting at 205°-206°, for analysis.
EXAMPLE 32
Preparation of 1-ethyl-5-methylcytosine
3.40 g. of 1-ethyl-4-thiothymine was added to 100 ml. of ethanol which had been saturated with ammonia at 5°. The solution was heated under pressure at 120° for 24 hours. The mixture was cooled in ice, and the crystalline product filtered and washed with cold ethanol to obtain 2.00 g. of 1-ethyl-5-methylcytosine, melting at 244°-247°.
The melting point was unchanged when a sample for analysis was prepared by recrystallization from ethanol.
EXAMPLE 33
Preparation of N 4 -acetyl-N 1 -(1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl) sulfanilamide
A mixture of 1.53 g. of 1-ethyl-5-methylcytosine, 2.34 g. of N-acetylsulfanilyl chloride and 10 ml. of pyridine was stirred overnight, diluted with 100 ml. of cold water, filtered with a little Hyflo to remove turbidity and acidified by addition of 19 ml. of 6N hydrochloric acid. The product was allowed to crystallize for several hours at room temperature before filtering, washing with water, and drying in a vacuum desiccator over potassium hydroxide to obtain 1.78 g. of N 4 -acetyl-N 1 -(1-ethyl-1,2-dihydro-5-methyl-4-pyrimidinyl)-sulfanilamide, melting at 235°-239°.
EXAMPLE 34
Preparation of N 1 -(1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl) sulfanilamide
A mixture of 1.00 g. of N 4 -acetyl-N 1 -(1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide and 10 ml. of 10% aqueous sodium hydroxide was heated for 1 hour on the steam bath, diluted with 20 ml. of water, cooled and acidified by gradual addition of acetic acid. The solid precipitate was filtered and washed with water to obtain 0.72 g. of product melting at 174°-176°. Recrystallization of 0.50 g. of this product from 30 ml. of ethanol gave 0.35 g. of N 1 -(1-ethyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide, melting at 176°-178°.
EXAMPLE 35
Preparation of 1-cyclopropyl-4-thiothymine
10.24 g. of ethyl (2-methyl-3-piperidino-thioacryloyl)-carbamate 3 were added with stirring to a solution of 2.52 g. of cyclopropylamine in 40 ml. of ethanol. The mixture was cooled slightly to keep the temperature below 32° when the product rapidly crystallized. After 30 minutes, the mixture was chilled in ice and filtered, to obtain 5.45 g. of 1-cyclopropyl-4-thiothymine, melting at 178°-180°.
3 R. W. Lamon, J. Het. Chem., 5, 837 (1968).
A sample for analysis was obtained by recrystallization from ethanol. The melting point was unchanged.
EXAMPLE 36
Preparation of 1-cyclopropyl-5-methylcytosine
7.50 g. of 1-cyclopropyl-4-thiothymine was added to 120 ml. of ethanol which had been saturated with ammonia at 5°. The solution was heated under pressure at 120° for 22 hours. The mixture was cooled in ice and the crystals filtered and washed with cold ethanol to obtain 5.33 g. of 1-cyclopropyl-5-methylcytosine, melting at 252°-256°.
A sample obtained for analysis by recrystallization from ethanol melted at 253°-255°.
EXAMPLE 37
Preparation of N 4 -acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide
A mixture of 0.83 g. of 1-cyclopropyl-5-methylcytosine, 1.17 g. of N-acetylsulfanilyl chloride and 4 ml. of pyridine was stirred overnight, diluted with 70 ml. of water, acidified with 8 ml. of 6N hydrochloric acid, and allowed to stand overnight in the refrigerator while gradual crystallization occurred. Filtration gave 0.60 g. of N 4 -acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide, melting at 176°-181°.
EXAMPLE 38
Preparation of N 1 -(cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl) sulfanilamide
A mixture of 500 mg. of N 4 -acetyl-N 1 -(1-cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide and 5 ml. of 10% aqueous sodium hydroxide was heated on the steam bath for 1 hour, diluted with 10 ml. of water, cooled and acidified by gradual addition of 1ml. of acetic acid. The initial oily precipitate quickly solidified and filtration gave 332 mg. of product melting at 128°-133°. Recrystallization from 7 ml. of ethanol gave 120 mg. of N 1 -cyclopropyl-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl)sulfanilamide, melting at 134°-136°.
Example 39
Example 39______________________________________Capsule Formulation Per Capsule______________________________________N..sup.1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide 50 mg.Lactose, U.S.P. 125 mg.Corn Starch, U.S.P. 30 mg.Talc, U.S.P. 5 mg.Total 210 mg.______________________________________
Procedure:
N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide is mixed with lactose and corn starch in a suitable mixer. The mixture is further blended by passing through a Fitzpatrick Comminuting Machine with a No. 1A screen with knives forward. The blended powder is returned to the mixer, the talc is added and blended thoroughly. The mixture is filled into No. 4 hard shell gelatin capsules on a Parke Davis capsulating machine.
EXAMPLE 40
Example 40______________________________________Tablet Formulation Per Tablet______________________________________N.sup.1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide (2% excess) 255 mg.Dicalcium Phosphate Dihydrate, Unmilled 230 mg.Corn Starch 70 mg.FD&C Yellow No. 5 - Aluminum Lake 25% 2 mg.Durkee 117* 25 mg.Calcium Stearate 3 mg.Total Weight 585 mg.______________________________________ *Mixture of di- and tri- C.sub.16 -C.sub.18 fatty acid esters of glycerin (primarily stearic acid with smaller amounts of palmitic and oleic acids)
Procedure:
All the ingredients are mixed thoroughly and Fitzed (Model D) using a No. 1A screen, medium speed. The mixture is remixed and slugged. The slugs are screened on an Oscillator through a No. 14 mesh screen and compressed on an "E" machine.
EXAMPLE 41
Example 41______________________________________Tablet Formulation mg/tab.______________________________________N.sup.1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4pyrimidinyl)sulfanilamide 4002,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine 80Microcrystalline Cellulose PH 102 75Corn Starch, Dried 10Methylcellulose 400 cps 9Microcrystalline Cellulose PH 1102 75Corn Starch, Dried 40Magnesium Stearate 2Total Tablet Weight 691______________________________________
Procedure:
N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide and 2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidines are mixed together in a suitable blender. The mixture is milled through a Fitzmill using No. 1 plate, hammers forward, high speed. The resulting mixture is granulated with 5% methylcellulose solution is distilled water and aged overnight in a refrigerator. The wet granulation is passed through a No. 5 screen, hammers forward, low speed, and dried overnight in a suitable oven at 120° F. The dried granulation is then milled through No. 2a plate, hammers forward, low speed. The microcrystalline cellulose PH 1102 and the dried corn starch are milled through a No. 1 screen, hammers forward, medium speed. The materials from the last two steps are mixed for 10 minutes in a suitable blender. The magnesium stearate is added to the above mixture and mixed for 2 minutes. The resulting material is then compressed into tablets having a weight of 691 mg. per tablet.
EXAMPLE 42
Example 42______________________________________Tablet Formulation mg/tablet______________________________________N.sup.1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide 8002,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine 160Pregelatinized starch 50Primojel 50Magnesium Stearate 5Total weight 1065 mg.______________________________________
Procedure:
The N 1 -(1-cyclohexyl-1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamide and 2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidine are mixed together in a suitable mixer for 10 minutes. The resulting mixture is milled through a No. 1A plate, knives forward, medium speed, Fitzmill. The mixture from the foregoing step is granulated with distilled water. The resulting granulation is passed through a No. 5 screen, knives forward, slow speed, Fitzmill. The granulation is racked and oven dried at 120° F overnight. The dried granulation is passed through a No. 12 wire mesh screen on a Fitzmill at low speed, knives forward. Thereafter, the primojel and magnesium stearate are added, and the resulting mixture mixed for 5 minutes. The granulation is pressed at 1,065 mg. on a suitable rotary tablet press. | N 1 -(1,2-dihydro-2-oxo-4-pyrimidinyl)sulfanilamides, bearing a lower alkyl, cycloalkyl or cycloalkyl-lower alkyl substituent in the 1-position, prepared by reaction of the corresponding 1-substituted-1,2-dihydro-2-oxo-4-aminopyrimidine and N-acylated sulfanilyl chloride with subsequent hydrolysis, are described. The end products are useful as antibacterial agents. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/893,808, filed on Mar. 8, 2007, which is incorporated herein by reference in its entirety.
FIELD
[0002] The present disclosure relates to substrates such as paving bricks, tile and the like having a cavity or channel with a photoluminescent portion arranged therein.
BACKGROUND
[0003] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0004] Referring now to FIGS. 1 and 2 , a non-powered photoluminescent paving brick 10 includes a paving brick base 14 that defines a cavity 16 . A photoluminescent laminate structure 20 is attached in the cavity 16 . The photoluminescent laminate structure is made before attachment in cavity 16 . Glue, resin or other adhesive material and/or mechanical fasteners may be used to attach the photoluminescent laminate structure 20 in the cavity 16 of the paving brick base 14 . For example, the photoluminescent paving brick 10 can be installed in a walkway to provide light during low light conditions. During daylight hours, the photoluminescent laminate structure 20 absorbs light energy. When the light is removed at dusk, the photoluminescent laminate structure 20 emits light or glows, which provides a non-powered source of light.
[0005] In FIG. 2 , the photoluminescent laminate structure 20 may include first and second transparent layers 24 and 28 that sandwich an inner photoluminescent layer 26 . The transparent layers 24 and 28 typically comprise glass or plastic. The inner layer 26 may comprise a resin layer with photoluminescent or phosphorescent particles suspended therein. The resin that is used typically cures in the absence of air since the resin layer is located between the transparent layers 24 and 28 . The resin is typically solvent-based and experiences shrinkage as the solvent is released as a gas. The resin also typically has a relatively high viscosity and low compressive and tensile strength.
[0006] One problem associated with the approach shown in FIGS. 1 and 2 includes relatively high material cost for the glass or plastic layers 24 and 28 . In addition, the manufacturing cost of the non-powered photoluminescent paving brick is also relatively high. In particular, creating a uniform layer of resin between the transparent layers 24 and 28 can be difficult.
[0007] In addition, the durability of the non-powered photoluminescent paving brick 10 may be suspect. There is a tendency for damage to occur when water seeps into gaps between the paving brick base 14 and the photoluminescent laminate structure 20 . Since the paving brick 10 is typically installed outdoors, the paving brick 10 is subject to wide temperature variation and standing water. When the water freezes and thaws, it expands and contracts and the laminate structure 20 experiences relatively high pressure. In addition, the photoluminescent laminate structure 20 may experience delamination when soaked in water—even in the absence of freezing temperatures. As a result, the photoluminescent laminate structure 20 may tend to delaminate, break or separate from the paving brick base 14 .
[0008] Furthermore, when an outer surface of the transparent layer 28 of the photoluminescent laminate structure 20 becomes wet, a coefficient of friction of the outer surface may be reduced. Since the paving brick 10 may often provide a walking surface, the non-powered photoluminescent paving brick 10 may be relatively slippery.
SUMMARY
[0009] A non-powered photoluminescent paving brick includes a substrate defining one of a cavity and a channel that extends from one end to an opposite end of the substrate. A photoluminescent portion includes a light transmissive resin including a suspension of photoluminescent particles. The photoluminescent portion is arranged in the one of the cavity and the channel and wherein the light transmissive resin has an exposed outer surface that directly receives light.
[0010] In other features, friction-enhancing particles are suspended in the photoluminescent portion. The photoluminescent portion has a first thickness, wherein the friction-enhancing particles have a cross-sectional dimension that is greater than the first thickness and wherein at least part of the friction-enhancing particles project outwardly from an outer surface of the photoluminescent portion. The photoluminescent portion comprises a plurality of stacked resin layers and wherein the friction-enhancing particles are suspended in one of the plurality of stacked resin layers.
[0011] In other features, the photoluminescent portion has a thickness that is greater than about 1/16″ and less than about ½″. The photoluminescent particles have a size between 2 and 200 microns. The light transmissive resin has a shrinkage factor that is less than 0.1%. The light transmissive resin is substantially solvent-free. The light transmissive resin has tensile and compressive strengths that are greater than about 1000 psi. The photoluminescent particles absorb ultraviolet light and re-emit visible light.
[0012] In other features, a reflective layer is arranged between an inner surface of the photoluminescent portion and the cavity, wherein the reflective layer comprises resin and at least one of pigment and reflective particles suspended therein. The channel has one of a rectangular, square or trapezoidal cross section perpendicular to a direction of the channel. The photoluminescent portion and the reflective layer have a combined thickness that is greater than or equal to about 1/16″ and less than or equal to about ½″. The photoluminescent portion and the reflective layer each have a thickness of about ⅛″. The resin in the reflective layer and the photoluminescent portion forms a substantially seamless bond during curing.
[0013] A non-powered photoluminescent paving brick comprises a substrate for the non-powered photoluminescent paving brick that includes plastic. A photoluminescent portion comprising a light transmissive resin including a suspension of photoluminescent particles formed on one surface of the substrate.
[0014] In other features, anchoring cavities are formed in the substrate, wherein the photoluminescent portion is received in the anchoring cavities. Friction-enhancing particles suspended in the photoluminescent portion. The photoluminescent portion has a first thickness, wherein the friction-enhancing particles have a cross-sectional dimension that is greater than the first thickness and wherein at least part of the friction-enhancing particles project outwardly from an outer surface of the photoluminescent portion. The light transmissive resin has a viscosity that is less than 1000 centipoise.
[0015] In other features, the photoluminescent portion has a thickness that is greater than about 1/16″ and less than about ½″. The photoluminescent particles have a size between 2 and 200 microns. The light transmissive resin has a shrinkage factor that is less than 0.1%. The light transmissive resin is substantially solvent-free. The light transmissive resin has tensile and compressive strengths that are greater than about 1000 psi.
[0016] In other features, anchoring cavities are formed in the substrate. The photoluminescent portion includes a first layer of the light transmissive resin that forms anchoring portions that extend from one side of the first layer into the cavities, wherein an opposite side of the first layer is substantially planar. A second layer is formed on the opposite side of the first layer and comprising the light transmissive resin and the suspension of photoluminescent particles.
[0017] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
[0018] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
[0019] FIG. 1 is a perspective view of a non-powered photoluminescent paving brick according to the prior art;
[0020] FIG. 2 is a cross-sectional view of the photoluminescent paving brick of FIG. 1 ;
[0021] FIG. 3A is a perspective view of a non-powered photoluminescent device according to the present disclosure;
[0022] FIG. 3B is a plan view illustrating a first cavity and an optional second cavity;
[0023] FIG. 4 is a cross-sectional view of the photoluminescent device of FIG. 3A ;
[0024] FIGS. 5A and 5B are cross-sectional views illustrating friction-enhancing particles suspended in a resin layer;
[0025] FIG. 6 is a cross-sectional view illustrating an outer surface having a higher coefficient of friction due to sanding or another abrasive method;
[0026] FIG. 7A is a perspective view of an alternate photoluminescent device with an embossed or grooved outward facing surface;
[0027] FIG. 7B is a cross-sectional view the embossed or grooved outer surface of the resin layer of FIG. 7A ;
[0028] FIG. 8 is a side cross-sectional view of a reflective layer and a resin layer with suspended photoluminescent particles;
[0029] FIG. 9 is a side cross-sectional view of a reflective layer, a resin layer with suspended photoluminescent particles and a layer with friction-enhancing particles;
[0030] FIGS. 10-14 illustrate various exemplary methods for making the non-powered photoluminescent paving brick according to the present disclosure;
[0031] FIG. 15 illustrates another exemplary photoluminescent device;
[0032] FIG. 16 illustrates a substrate of FIG. 15 in further detail;
[0033] FIG. 17 illustrates an alternative substrate with anchoring cavities;
[0034] FIG. 18 illustrates a multi-layer photoluminescent portion;
[0035] FIG. 19 illustrates another exemplary photoluminescent paving brick or other a substrate with a channel formed from one end to an opposite end thereof and photoluminescent portion in the cavity;
[0036] FIG. 20 is an end view of the exemplary photoluminescent device of FIG. 19 ; and
[0037] FIG. 21 is an alternate end view of the exemplary photoluminescent device of FIG. 19 .
DETAILED DESCRIPTION
[0038] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. Unless otherwise stated herein, it is understood that features described with respect to one embodiment or FIG. may be used in any other FIG. or embodiment described herein.
[0039] Referring now to FIGS. 3A , 3 B and 4 , a non-powered photoluminescent device 100 according to the present disclosure is shown. While the present disclosure will describe exemplary paving bricks, the techniques described herein may be applied to any suitable substrate with a cavity or channel. For example, the substrate may include cement, asphalt, tile, other floor materials, decorative molding or other substrates.
[0040] The non-powered photoluminescent device 100 includes a paving brick or other substrate 102 defining a cavity 104 . The cavity 104 may be formed during manufacturing or cut after manufacturing. While a rectangular cavity is shown, the cavity 104 may have any suitable shape. The cavity 104 may have a shape in the form of letters, logos, or other suitable shapes. Two or more adjacent paving bricks may have different-shaped cavities that together form a shape. For example only, multiple paving bricks may show a direction of a walking path.
[0041] A photoluminescent resin layer 106 may be cast, molded or formed in the cavity 104 . Alternatively, the photoluminescent resin layer 106 may be cast, molded or formed and then later installed in the cavity 104 . The same resin may be used to adhere the layer 106 in the cavity 104 . The photoluminescent resin layer 106 includes a transparent resin material with photoluminescent or phosphorescent particles suspended therein, as will be described further below.
[0042] In FIG. 3B , the cavity 104 may optionally include a second cavity 130 having a regular or irregular shape. The second cavity 130 may be smaller than the cavity 104 . The second cavity 130 is shown with an irregular shape. Examples of regular shapes include squares, circles, polygons, and/or other symmetric shapes. The second cavity 130 provides additional surface area to which the resin may attach inside the cavities 104 and 130 . As a result, durability may be improved. The second cavity 130 may also be used as a watermark to differentiate genuine paving bricks from knock-off paving bricks.
[0043] In some implementations, the resin may include a two-part resin. The resin may be a solvent-free resin that experiences negligible shrinkage during curing. The resin may experience negligible evaporation during curing. The resin may experience less than 0.1% shrinkage. More particularly, the resin may experience less than 0.01% shrinkage. For example only, the resin may be Crystal Clear™ resin available from Smooth-On located in Pennsylvania, United States. Crystal Clear™ 202 resin may be used, although other resins are contemplated.
[0044] The resin may have a high tensile strength after curing. The resin may have tensile and compressive strengths greater than about 1000 psi. The resin may have a tensile and compressive strength greater than 2000 psi. Crystal Clear™ 202 has a tensile strength of 2800 psi, a compressive strength of 2208 psi and a shrinkage factor or approximately 0.0013 inches per inch. The resin may be clear and UV resistant.
[0045] The resin may have a relatively low viscosity to allow the resin to seep into pores of the paving brick or substrate to ensure that the photoluminescent resin layer 106 attaches securely to a surface of the cavity 104 . In other words, high viscosity material may not seep into the pores of the substrate and adequately bond therewith, which may result in delamination. For example, Crystal Clear™ 202 has a viscosity of approximately 600 centipoise (cps) at 72° F. The resin may have a viscosity that is less than 1500 cps at 72° F. The resin may have a viscosity that is less than 1000 cps at 72° F. The resin may have a viscosity that is about 600 cps at 72° F. plus or minus 100 cps.
[0046] When multiple layers of the resin are used and fully or partially cured, the resin may form relatively seamless bonds between the layers. In other words, the multiple layers bond together and form a relatively seamless unitary structure that does not have compromised strength. Furthermore, the resin does not experience delamination of the multiple layers after curing. The bonds may also be optically clear after curing.
[0047] In some implementations, the photoluminescent resin layer 106 may have a thickness between ⅛″ and ½″, although other thicknesses may be used. In some implementations, the resin layer 106 may include between 3 grams (g) and 200 g of photoluminescent particles per ⅛″ resin layer per 10 in 2 . In some implementations, the resin layer 206 may include between 5-100 g of photoluminescent particles per ⅛″ layer per 10 in 2 . Other ranges such as 5-30 g or 5-15 g may be used. The photoluminescent particles may have a size between 2 and 200 microns. More particularly, the photoluminescent particles may have a size of about 70 microns. Other photoluminescent particles may a size of 200 microns.
[0048] Suitable photoluminescent particles include long decay phosphors described in U.S. Pat. No. 5,376,303, long afterglow phosphors of U.S. Pat. No. 5,885,483 and photostorage and emissive materials of U.S. Pat. No. 6,177,029, which are all hereby incorporated by reference in their entirety.
[0049] The long decay phosphor of U.S. Pat. No. 5,376,303 is comprised of MO.a(A1 1-b B b ) 2 O 3 :cR herein:
0.5≦a≦10.0, 0.0001≦b≦0.5 and 0.0001≦c≦0.2,
MO represents at least one divalent metal oxide selected from the group consisting of MgO, CaO, SrO and ZnO and R represents Eu and at least one additional rare earth element selected from the group consisting of Pt, Nd, Dy and Tm.
[0053] In U.S. Pat. No. 5,885,483, the long afterglow phosphors comprise a sinter expressed by a general formula MO.(n−x){a A1 2 O 3 a*(1−a)A1 2 O 3 y }B 2 O 3 :R wherein M represents an alkaline earth metal, T represents a rare earth element, 0.5<a≦0.99, 0.001≦x≦0.35, 1≦n≦8 and a part of M may be replaced with at least one alkaline earth metal selected from the group consisting of Mg, Ca and Ba.
[0054] The photostorage and emissive material of U.S. Pat. No. 6,177,029 is composed of photoluminescent material that absorbs light from a light source such as UV light. The photoluminescent material re-emits the light energy in a first wavelength spectrum when the light source is removed. A second material is mixed with the photoluminescent material. The second material is selected from the group consisting of fluorescent colorants and optical brighteners that absorb light at the first wavelength spectrum and re-emit the absorbed light at a second wavelength spectrum. The phosphorescent particles described herein may absorb light at ultraviolet wavelengths and re-emit light at visible wavelengths.
[0055] In use, the non-powered photoluminescent device 100 absorbs ultraviolet light energy into the photoluminescent particles, which store the energy until a source of light is removed. For outdoor applications, the source of light may be removed when the sun goes down. For other applications, the source of light may be removed when a powered source of light is turned off (for example intentionally, due to power failure or other emergency). When the source of light is removed, the particles emit light energy in the visible spectrum.
[0056] The photoluminescent particles can be the photoluminescent particles described above and in the concentrations described above (hereinafter high light (HL) photoluminescent particles). The photoluminescent particles are called HL due to their ability to be charged outdoors by UV light with only ordinary degradation of the photoluminescent particles. The photoluminescent particles may be charged on cloudy days since UV light will be present—unlike some solar powered devices.
[0057] In other embodiments, low light (LL) photoluminescent particles are used alone or in combination with the HL photoluminescent particles. The LL photoluminescent particles have a shorter charge time and require lower levels of UV light to charge. The LL photoluminescent particles charge with indoor sources of light but experience accelerated degradation if charged with higher intensity outdoor light. The LL photoluminescent particles may be suitable for indoor applications.
[0058] The LL photoluminescent particles may include GLL300M available under the trademark Luminova® from United Mineral and Chemical Corp. of Lyndhurst, N.J. and Nemota & Co. LTD. of Tokyo, Japan. The HL photoluminescent particles may include G300, BG300 or V300 available under the trademark Luminova® from United Mineral and Chemical Corp. and Nemota & Co. LTD. of Tokyo, Japan. As can be appreciated, the photoluminescent resin layers described above can also be implemented using LL, HL and/or LL and HL photoluminescent particles. LL photoluminescent particles may be suitable for indoor applications such as indoor pavers, tile, molding, trim, swimming pool steps, risers and the like.
[0059] Referring now to FIGS. 5A and 5B , friction-enhancing particles can be added to the resin layer that includes the photoluminescent particles. In FIG. 5A , a photoluminescent device 150 includes a cavity 154 and a photoluminescent resin layer 156 . Friction-enhancing particles 158 may be added to the photoluminescent resin layer 156 .
[0060] The friction-enhancing particles 158 may have an outer dimension that is greater than a thickness “d” of the photoluminescent layer 156 such that at least part of the frictional particles project outwardly from an outer surface of the photoluminescent layer 156 . The thickness “d” may be greater than or equal to 1/16″ and less than or equal to ½″. The thickness “d” may be about ⅛″. Still other thicknesses are contemplated.
[0061] The friction-enhancing particles 158 may be transparent or clear to allow light to pass through. In some implementations, the friction-enhancing particles 158 may include Aluminum Oxide (AlO 2 ) particles, Silica particles, and/or Quartz particles, although other materials may be used. The friction-enhancing particles 158 may be mixed with the resin and the photoluminescent particles and then poured into the cavity 154 . Alternately the friction-enhancing particles may be added to a mixture of the resin and photoluminescent particles after the mixture has been poured into the cavity 154 . The friction-enhancing particles may have any suitable shape.
[0062] In FIG. 5B , the friction-enhancing particles 158 have an outer dimension that is less than a thickness “d” of the photoluminescent layer 156 . There are several ways to implement the embodiment in FIG. 5B . For example only, the photoluminescent particles 158 can be added after the resin in the photoluminescent portion has been poured into the cavity and has at least partially cured. The increased viscosity due to partial curing may allow the friction-enhancing particles to float above the outer surface while being part of the resin layer. Alternately, the friction-enhancing particles can be selected to have a density that is less than the density of the resin in the photoluminescent layer 156 . These lower-density friction-enhancing particles can be added to the mixture before or after pouring. Since the density is lower, they will tend to float at least partially above the outer surface. Still other variations are contemplated. The friction-enhancing particles may be glued to an outer surface after the outer layer has cured.
[0063] Referring now to FIG. 6 , a photoluminescent device 200 includes a cavity 204 formed in a paving brick or other substrate 202 and a photoluminescent resin layer 206 in the cavity 204 . An abrasive material such as sanding paper or a grinding wheel may be used to scuff an outer surface 210 of the photoluminescent layer 206 to increase a coefficient of friction of the outer surface 210 . The photoluminescent resin layer 206 may have a thickness greater than or equal to 1/16″ and less than or equal to ½″. The photoluminescent resin layer 206 may have a thickness of approximately ⅛″. Still other thicknesses are contemplated.
[0064] Referring now to FIGS. 7A and 7B , an alternate photoluminescent device 250 with an embossed or grooved outer surface is shown. In FIG. 7A , a photoluminescent device 250 includes a cavity 254 formed in a paving brick or other substrate 252 and a photoluminescent resin layer 256 in the cavity 254 . After the photoluminescent portion is at least partially cured, an outer surface thereof is scored or embossed at 260 to create raised portions 270 and/or lowered portions 272 as can be seen in FIG. 7B . The raised and/or lowered portions 270 and 272 , respectively, tend to increase a coefficient of friction of the outer surface. The photoluminescent resin layer 256 may have a thickness greater than or equal to 1/16″ and less than or equal to ½″. The photoluminescent resin layer 256 may have a thickness of approximately ⅛″. Still other thicknesses are contemplated.
[0065] Referring now to FIG. 8 , a photoluminescent device 300 includes a cavity 304 . A photoluminescent resin layer 306 is arranged over a reflective layer 310 in the cavity 304 . The reflective layer 310 may comprise any material that increases reflectivity of light incident thereon. The reflective layer 310 may include a paint layer applied to a surface of the paving brick. Alternately, the reflective layer 310 may include a layer of resin mixed with a light pigment such as a white, silver or other light colored pigment. Alternately, the reflective layer 310 may include a zinc metallic powder that is mixed with a resin layer. Other reflective layers may include a light colored fabric that is resin-permeable so that the resin may seep through the fabric and attach itself along a bottom surface of the cavity.
[0066] If the layer of resin mixed with pigment or zinc metallic powder is used, the layer may have a thickness greater than or equal to 1/16″ and less than or equal to ½″. The layer of resin may have a thickness of approximately ⅛″. The photoluminescent resin layer 306 may have a thickness greater than or equal to 1/16″ and less than or equal to ½″. The photoluminescent resin layer 306 may have a thickness of approximately ⅛″. Still other thicknesses are contemplated.
[0067] Referring now to FIG. 9 , a photoluminescent device 350 includes a cavity 354 formed in a paving brick or other substrate 352 . A reflective layer 360 is arranged in the cavity 354 . A photoluminescent layer 358 is arranged above the reflective layer 360 . A resin layer 361 is added and includes friction-enhancing particles 362 . The friction-enhancing particles 362 may have an outer dimension that is greater than a thickness of the outer resin layer 361 . As a result, at least part of the friction-enhancing particles project outwardly from an outer surface of the photoluminescent layer 361 . Alternately, the friction-enhancing particles may be implemented as shown in FIG. 5B .
[0068] The reflective layer 360 , the photoluminescent layer 358 and the resin layer 361 may have a combined thickness greater than 3/16″ and less than ½″. The lower reflective layer 360 , the middle photoluminescent layer 358 and the outer resin layer 361 may each have a thickness of approximately ⅛″. Still other thicknesses are contemplated.
[0069] Referring now to FIG. 10-14 , various exemplary methods for making the photoluminescent device according to the present disclosure are shown.
[0070] In FIG. 10 , a first method 400 for making a non-powered photoluminescent substrate is shown. In step 408 , resin is mixed with photoluminescent particles. In step 412 , the mixture is poured into a cavity in a substrate. In step 414 , the mixture is allowed to cure. In step 418 , a coefficient of friction of an outer surface of the photoluminescent portion may be optionally increased using any of the methods described above.
[0071] In FIG. 11 , another method 430 for making a non-powered photoluminescent substrate is shown. In step 434 , resin is mixed with pigment or zinc metallic powder. In step 436 , the mixture is poured into a cavity in a substrate. In step 440 , the mixture is allowed to cure or an outer skin is formed. An outer skin forms before curing occurs. In step 444 , resin is mixed with photoluminescent particles. In step 446 , the mixture is poured into the cavity. In step 450 , the mixture is allowed to cure.
[0072] In FIG. 12 , another method 460 for making a non-powered photoluminescent substrate is shown. In step 464 , resin is mixed with photoluminescent particles and friction-enhancing particles. In step 468 , the mixture is poured into a cavity. In step 470 , the mixture is allowed to cure.
[0073] In FIG. 13 , another method 500 for making a non-powered photoluminescent substrate is shown. In step 504 , resin is mixed with a pigment. The mixture is poured into a cavity of a substrate in step 510 . In step 514 , the mixture is allowed to cure or form a skin. In step 516 , the resin is mixed with photoluminescent particles and friction-enhancing particles. In step 520 , the mixture is poured into the cavity of the substrate. In step 524 , the mixture is allowed to cure.
[0074] In FIG. 14 , another method 550 for making a non-powered photoluminescent substrate is shown. In step 554 , resin is mixed with pigment or zinc metallic powder as described above. In step 558 , the mixture is poured into a cavity of a substrate. In step 560 , the mixture is allowed to cure or form a skin. In step 564 , the resin is mixed with photoluminescent particles. In step 570 , the mixture is poured into the cavity of the substrate. In step 572 , the mixture is allowed to cure and/or form a skin. In step 574 , the resin is mixed with friction-enhancing particles. In step 578 , the mixture is poured into a cavity. In step 580 , the mixture allowed to cure.
[0075] In any of the foregoing embodiments, curing may be performed by allowing air drying. Alternately, curing may be accelerated using heat. In addition, cure enhancing additives may be added to the resin mixture.
[0076] Advantages of the foregoing include reduced manufacturing cost as compared to other approaches. In addition, the structure is more durable and resistant to the adverse effects of weather. Furthermore, the transparent layers are eliminated. These structures may reduce light incident upon the photoluminescent particles and may also reduce the intensity of the glow.
[0077] While the photoluminescent portion can be cast, molded or formed in the cavity or channel, the photoluminescent portion can be formed, cast or molded outside of the cavity or channel and then installed in the cavity or channel using an adhesive. For example only, the resin used for the photoluminescent portion can be used as an adhesive to attach the photoluminescent portion in the cavity or channel and to create a seamless bond.
[0078] Referring now to FIGS. 15 and 16 , another exemplary photoluminescent paving brick or other device 600 comprises a substrate 602 and a photoluminescent portion 604 . The substrate 602 can be made of high strength plastic that can be molded, cast or injected. The photoluminescent portion 604 may be formed as described above and may include any of the features described above. The plastic may include a material selected from a group consisting of Polypropylene, Nylon, Nylon 6, Nylon 6-6, Polybutylene Terepthalate (PBT) Polyester, Acrylic or other high tensile strength plastic. The plastic may have a high tensile strength sufficient to allow sidewalk or driveway traffic. The plastic may have a tensile strength greater than or equal to approximately 2000-3000 psi for light traffic. For heavy traffic, the plastic may have a tensile strength greater than approximately 7000-8000 psi. For pressures, the term approximately shall mean +/−500 psi. As can be appreciated, the lighter weight of the plastic substrate brick will make the bricks easier to ship.
[0079] The substrate 602 may have a generally rectangular shape, a circular shape, a square shape, a symmetric shape, a polygon shape and/or any other suitable shape. Raised portions 610 - 1 A, 610 - 1 B, 610 - 2 A, 610 - 2 B, 610 - 3 A, and 610 - 3 B (collectively raised portions 610 ) may be formed along sides of the substrate 602 . Corresponding raised portions 612 - 1 A, 612 - 1 B, 612 - 2 A, 612 - 2 B, 612 - 3 A, and 612 - 3 B (collectively raised portions 612 ) may be formed along sides of the photoluminescent portion 604 .
[0080] The raised portions 610 may align with corresponding ones of the raised portions 612 . The raised portions 610 and 612 are offset such that they do not abut corresponding raised portions 610 and 612 on an adjacent paving brick when installed. As a result, sand, dirt or other filler material may be easily inserted between the abutting paver bricks to limit movement of the paver bricks.
[0081] Referring now to FIG. 17 , an alternative substrate with anchoring portions between the photoluminescent portion and the substrate is shown. The substrate 602 defines one or more anchoring cavities 622 (anchoring cavities 622 - 1 and 622 - 2 are shown) that allow part of the photoluminescent portion 604 to enter during manufacturing (casting or molding).
[0082] When the material dries, the photoluminescent portion 604 is securely held to the substrate 602 . This structure greatly enhances strength—which may be helpful when the paving brick is subjected to changing temperatures and moisture. For example, the part of the photoluminescent portion 604 that enters the anchoring cavities 622 may include the resin alone, a mixture of the resin and photoluminescent particles (and/or other materials). As a result, the photoluminescent portion 604 forms one or more anchoring portions 624 (anchoring portions 624 - 1 and 624 - 2 are shown) that are secured in the anchoring cavities 622 - 1 and 622 - 2 .
[0083] Referring now to FIG. 18 , two or more layers can be used to form the photoluminescent portion 604 . A first layer 634 may be applied in the cavity and in the anchoring cavities 622 - 1 and 622 - 2 . After full or partial curing, a second layer 636 may be applied on top of the first layer 634 .
[0084] The first layer 634 may comprise resin, resin and pigment (such as white pigment), resin and photoluminescent particles, or resin and any other material. The second layer 636 may comprise resin and photoluminescent particles. When a single layer is applied as in FIG. 17 , the photoluminescent particles may tend to fall to a lowest point due to their heavier specific gravity. As a result, the photoluminescent particles may end up concentrating in the anchoring cavities 622 - 1 and 622 - 2 , which can be seen when viewing the paving brick from the top. Furthermore, some of the resin described herein are relatively optically clear after curing and do not tend to show boundaries between cured layers. Therefore, when two or more layers are used and first layer does not include photoluminescent material, the anchoring cavities are less longer visible from the top of the paving brick.
[0085] As can be appreciated, the anchoring cavities 622 may be made parallel to each other. Alternately, additional anchoring portions may be used and may be arranged at different angles to increase strength.
[0086] In some implementations, the substrate is formed of plastic using any suitable process. For example, thermoforming, injection molding, CNC machining or any other suitable approach may be used. Additionally, post forming steps such as CNC milling can be used to trim edges and/or to form anchoring cavities. Alternately, these anchoring structures can be formed during manufacturing.
[0087] Referring now to FIG. 19 , another exemplary photoluminescent paving brick 650 includes a substrate 652 . The substrate 652 may be a conventional paving brick. A channel 654 is created from one end 656 to an opposite end 658 of the substrate 652 . The channel can be created during manufacturing of the paving brick or cut after the paving brick is manufactured.
[0088] A photoluminescent portion 662 is molded, cast or formed in the channel or pre-formed, molded or cast and adhered in the channel with adhesive as described above. The photoluminescent portion 662 may comprise one or more layers as described herein.
[0089] As can be appreciated, the cavities described above may be formed in the paving brick during manufacturing of the paving brick. Alternately, the cavities described herein can be routed or drilled in the paving brick after manufacturing the paving brick. A more simple approach may be to use the channel 654 . For example, the channel 654 may be created using a router bit that cuts from one end to the other rather than a plunge cutting method used to form a central cavity. The plunge cutting methods may tend to be more time consuming and expensive.
[0090] Referring now to FIGS. 20 and 21 , exemplary end views of the exemplary photoluminescent paving brick of FIG. 19 are shown. The channel can have a rectangular or square end view. Alternately, the channel can have a trapezoidal cross section or other cross section with an undercut region to more securely hold the photoluminescent portion therein. | A non-powered photoluminescent paving brick includes a substrate defining one of a cavity and a channel that extends from one end to an opposite end of the substrate. A photoluminescent portion includes a light transmissive resin including a suspension of photoluminescent particles. The photoluminescent portion is arranged in the one of the cavity and the channel and wherein the light transmissive resin has an exposed outer surface that directly receives light. | 8 |
BACKGROUND OF THE INVENTION
[0001] Naphtha produced from various refinery units, including the Crude and Vacuum Unit, Coker Unit, and others, forms a significant part of the gasoline product pool, and is a major source of the sulfur found in gasoline. This sulfur impurity typically must be removed to comply with various product specifications and/or environmental regulations.
[0002] Hydrodesulfurization is a catalytic chemical process used to remove sulfur from a naphtha feed, as well as other petroleum products. Removing the sulfur from these products reduces sulfur dioxide emissions that result from use of the products in fuel combustion. Moreover, removing the sulfur provides benefits within a petroleum refinery because sulfur, even in very small quantities, can adversely affect noble metal catalysts used in downstream processes, such as catalytic reforming.
[0003] Conventional fixed bed hydrodesulfurization can reduce the sulfur level of a naphtha feed. During hydrodesulfurization, the raw feed reacts with hydrogen in the presence of a catalyst to convert organic sulfur compounds to hydrogen sulfide. However, the hydrogen sulfide formed during the hydrodesulfurization recombines with olefins in the naphtha feed to form mercaptans, known as recombination mercaptans. In particular, it has been found that presence of recombination mercaptans is increased when the operating temperature of the hydrotreating reactor is high. For instance, temperatures in excess of 650° F. have been found to increase formation of recombination mercaptans.
[0004] The hydrodesulfurization process generally involves a hydrogenation reaction, which cleaves a chemical bond between a carbon atom and a sulfur atom in the hydrocarbon.
[0005] This hydrogenation reaction is exothermic, causing the temperature of effluent leaving the hydrotreater reactor to increase over time. This can cause a corresponding increase in the formation of recombination mercaptans. A post-treat reactor is required to remove the recombination mercaptans by converting mercaptans into hydrogen sulfide.
[0006] Accordingly, there is a need to control the temperature of the naphtha feed flowing through the post-treat reactor.
SUMMARY OF THE INVENTION
[0007] In one aspect, a process for controlling a temperature of fluid entering a post treat reactor in a naphtha hydrotreater includes measuring a temperature of hydrotreater reactor effluent and determining a set point based on the measured temperature. The set point is transmitted to a first temperature indicator controller, and the first temperature indicator controller measures a temperature of fluid flowing into a post treat reactor and adjusts a combined feed flow through a bypass of an upstream combined feed exchanger. This reduces an amount of heat exchanged in the combined feed exchanger and thus prevents the fluid temperature of the fluid entering the post treat reactor from falling below the set point.
[0008] In another aspect, a process for controlling the temperature of fluid entering a post treat reactor in a naphtha hydrotreater includes measuring a temperature of hydrotreater reactor effluent and communicating the measured temperature to a remote set point calculator. The remote set point calculator determines a set point of a first temperature indicator controller based on the measured temperature and transmits the set point from the remote set point calculator to the first temperature indicator controller, The first temperature indicator controller measures a temperature of fluid at a post treat reactor inlet and adjusts a combined feed flow through a bypasss of an upstream combined feed exchanger, reducing the amount of heat exchanged in the combined feed exchanger and preventing the temperature of the fluid entering the post treat reactor from falling below the set point of the first temperature indicator controller. The process further includes transmitting the temperature measured by the first temperature indicator controller to a second temperature indicator controller as a process value. The second temperature indicator controller compares the transmitted temperature process value to a set point specified in the second temperature indicator controller and controls flow of a quench fluid into an inlet of the post treat reactor inlet based on a difference between the transmitted temperature process value and the set point of the second temperature indicator controller so that the fluid temperature at the post treat reactor inlet does not exceed the set point of the second temperature indicator controller.
[0009] In yet another aspect, a temperature control device for use with a hydrotreater reactor and a post treat reactor includes a remote set point calculator configured to determine and transmit a set point temperature. The device further includes a temperature indicator in communication with the remote set point calculator. The temperature indicator is configured for measuring a temperature of effluent leaving the hydrotreater reactor and communicating the measured temperature to the remote set point calculator. A first temperature indicator controller is in communication with the remote set point calculator, the first temperature indicator controller measuring a temperature of effluent entering the post treat reactor and comparing the measured temperature of effluent entering the post treat reactor with the set point temperature transmitted by said remote set point calculator. The first temperature indicator controller is configured for controlling a combined feed flow through a bypass of an upstream heat exchanger to prevent fluid temperature of fluid entering the post treat reactor from falling below the set point. The remote set point calculator determines the set point based on the temperature of effluent leaving the hydrotreater reactor measured at said temperature indicator.
BRIEF DESCRIPTION OF THE DRAWING
[0010] The FIGURE illustrates one embodiment of a hydrotreating process flow incorporating the post treat reactor inlet temperature control process of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] A process has been developed to control the temperature of fluid entering a post treat reactor in a hydrotreating unit.
[0012] Referring now to the FIGURE, a hydrotreating process flow 10 is shown. A hydrocarbon feed 12 , such as naphtha, is pumped to a hydrotreating unit through a charge pump 14 . After exiting the charge pump 14 , the feed 12 is separated into a first portion 16 and a second portion 18 . The first portion 16 is mixed with a recycle gas 20 and is passed through a cold combined feed heat exchanger 22 , forming a heated feed 24 . The second portion 18 bypasses the cold combined feed heat exchanger 22 and rejoins the heated feed 24 to from a combined feed 26 .
[0013] The combined feed 26 is then split into a first portion 28 and a second portion 30 . The first portion 28 of the combined feed 26 passes through a hot combined feed heat exchanger 32 . The second portion 30 bypasses the hot combined feed heat exchanger 32 and rejoins the first portion 28 to form a heated combined feed 34 . The heated combined feed 34 is then further heated in a charge heater 36 . A temperature indicator controller 38 measures a temperature of the heated combined feed 34 at or near an inlet of the charge heater 36 and controls the flow of the second portion 18 bypassing the cold combined feed heat exchanger 22 , thus controlling the ratio of the first portion 16 and the second portion 18 , based on the measured temperature. To control the flow of the second portion 18 bypassing the cold combined feed heat exchanger 22 , an operative connection 40 connects the temperature indicator controller 38 to a cold combined feed bypass control valve 42 , such that the valve can be adjusted based on the temperature measured at the temperature indicator controller. The operative connection 40 may be, for example, an electrical, mechanical, or electromechanical connection, a wired data connection, a wireless data connection, or other known means for allowing the temperature indicator controller 38 to adjust the valve 42 .
[0014] When exiting the charge heater 36 , a feed 44 has been heated to a desired reaction temperature. As an example, the feed 44 exiting the charge heater 36 is heated to be in the range of about 550° F. (288° C.) to about 650° F. (343° C.), and preferably approximately 600° F. (315° C.). After exiting the charge heater 36 , the feed 44 enters a hydrotreating reactor 46 at an inlet 48 .
[0015] The reactor 46 contains a catalyst for converting contaminants such as sulfur, nitrogen, oxygenates, and halides to hydrogen sulfide, ammonia, water, and hydrogen halides via hydrogenation reactions, as is known in the art. Suitable catalysts may include, for example cobalt-molybdenum or nickel-molybdenum catalysts, as well as other catalysts.
[0016] Hydrotreater effluent 50 leaves the hydrotreating reactor 46 through an outlet 52 , and the temperature of the effluent is measured using a temperature indicator 54 positioned at or near the reactor outlet. The hydrotreater effluent 50 passes through the hot combined feed exchanger 32 to heat the first portion of the combined feed 28 before it enters the charge heater 36 . This path also advantageously cools the effluent 50 before it enters a post-treat reactor 56 . A data connection 58 connects the temperature indicator 54 to a remote set point calculator 60 . The data connection 58 includes, for example, wired and/or wireless data connections, electrical connections, or other known means for communicating data, including a temperature measured at the temperature indicator, to the remote set point calculator 60 . The temperature measured by the temperature indicator 54 is transmitted to the remote set point calculator 60 . The remote set point calculator 60 then determines a set point temperature for the effluent 50 entering the post-treat reactor based on the received temperature data. The remote set point calculator 60 can be, for example, a computer running software to determine the set point, an electrical circuit hardwired to determine a set point, or any combination of hardware and software that can be used to determine the set point.
[0017] The set point temperature is determined based on the measured temperature transmitted to the remote set point calculator 60 . One example algorithm that may be used is, for example, if the measured temperature is greater than 650° F. (343° C.), then the remote set point calculator 60 determines the set point temperature of effluent entering the post treat reactor to be in the range of about 550° F. (288° C.) to about 600° F. (315° C.), and more preferably 600° F. (315° C.); if the measured temperature is 650° F. or less, the remote set point calculator determines the set point temperature to be 550° F. (288° C.). Those of skill in the art will recognize the set point temperatures determined by the remote set point calculator 60 may be adjusted without departing from the scope of the invention. Likewise, while the example algorithm described above may be used to establish a set point temperature, different algorithms may also be used without departing from the scope of the invention.
[0018] The remote set point calculator 60 is connected to a first temperature indicator controller 62 positioned at an inlet of the post treat reactor 56 by a data connection 64 . The data connection 64 can be, for example, a wired or wireless data connection, as is known in the art, an electrical connection, or other known connection capable of communicating the determined set point temperature from the remote set point calculator 60 to the first temperature indicator controller 62 . The determined set point temperature is communicated to the first temperature indicator controller 62 .
[0019] When effluent 50 from hydrotreating reactor reaches the first temperature indicator controller 62 after passing though the hot combined feed exchanger 32 , the first temperature indicator controller measures the temperature of the reactor effluent at the post treat reactor 56 inlet, and compares the measured temperature to the set point temperature received from the remote set point calculator 60 . The first temperature indicator controller 62 is connected to an upstream valve 66 by an operative connection 68 , and controls the valve to adjust the flow of the heated combined feed 26 through the hot combined feed heat exchanger 32 so that the temperature of the effluent 50 measured at the first temperature indicator controller does not fall below the set point temperature. More specifically, in some embodiments, the first temperature indicator controller 62 controls the upstream valve 66 so that the temperature of effluent 50 matches the set point temperature. In particular, when the first portion 28 of the hot combined feed 26 passing through the hot combined feed exchanger 32 is relatively large, the effluent 50 from hydrotreating reactor 46 contacts more of the relatively cool feed 28 and is cooled more. Conversely, when the second portion 30 of the feed 26 bypassing the hot combined feed heat exchanger 32 is relatively large, the effluent 50 from hydrotreating reactor 46 is cooled less, allowing the temperature of the effluent to remain higher. The operative connection 68 between the first temperature indicator controller 62 and the upstream valve 66 can be, for example, an electrical, mechanical, or electromechanical connection, a wired or wireless data connection, or other known connection usable to control operation of the valve.
[0020] Because the hydrotreating reactions that take place in the hydrotreater reactor 46 are exothermic, the temperature of the effluent 50 gradually increases as the reactor runs. However, the post treat reactor 56 is preferably operated at a temperature range of about 600° F. (315° C.) to about 650° F. (343° C.). The exothermic reaction eventually increases the temperature of the reactor effluent 50 substantially, so that the first temperature indicator controller 62 is no longer capable of maintaining the temperature at the set point using the upstream valve 66 .
[0021] A data connection 70 connects the first temperature indicator controller 62 to a second temperature indicator controller 72 such that data can be transmitted at least from the first temperature indicator controller to the second temperature indicator controller. The connection 70 can be, for example, a connection capable of wired or wireless data transmission, an electrical connection, or the like. Further, an operative connection 74 connects the second temperature indicator controller 72 to a valve 76 that controls the flow of a quench liquid into the effluent 50 upstream of the first temperature indicator controller 62 . The operative connection 74 can be, for example, an electrical, mechanical, or electromechanical connection, a wired or wireless data connection, or other known connection usable to control operation of the valve 76 .
[0022] The first temperature indicator controller 62 transmits, as a process value, the temperature measured at the inlet to the post treat reactor 56 to the second temperature indicator controller 72 using the data connection 70 . The second temperature indicator controller 72 has a set point that approximately matches the maximum temperature of the post treat reactor 56 . For example, when the post treat reactor 56 is run at temperatures in the range of 600° F. (315° C.) to 650° F. (343° C.) as discussed above with a maximum temperature of 650° F. (343° C.), the set point of the second temperature indicator controller 72 is preferably similarly set to be within a range of approximately 630° F. (332° C.) to 650° F. (343° C.), and more preferably is set to approximately 650° F. (343° C.). The second temperature indicator controller 72 compares the received temperature process value from the first temperature indicator controller 62 to the set point, and adjusts the valve 76 controlling flow of quench fluid to further adjust the temperature so that it does not exceed the set point of the second temperature indicator controller. Together, the remote set point calculator 60 , temperature indicator 54 , first temperature indicator controller 62 , and second temperature indicator controller 72 form a temperature control device for the post treat reactor 56 .
[0023] The quench fluid preferably includes a recycle gas 20 from the hydrotreater, though it will be recognized by those of skill in the art that other quench fluids may be used without departing from the scope of the invention.
[0024] After passing through the hot combined feed heat exchanger 32 , the effluent 50 from the hydrotreating reactor 46 then enters the post treat reactor 56 to treat the recombination mercaptans formed due to recombination reactions in the hydrotreating reactor, as is known in the art. After leaving the post treat reactor 56 , post treat reactor effluent 78 flows through the cold combined feed heat exchanger 22 to heat the feed first portion 16 and cool the effluent 78 . Then, wash water 80 is injected into the effluent 78 , and the effluent is further cooled in a condenser 82 to produce a material 84 .
[0025] Thereafter, the material 84 enters a product separator 86 to remove sour water 88 . The remainder 90 is sent to a stripping column 92 , where it is separated into at least a gaseous component 94 and a hydrotreated naphtha component (not shown). The gaseous component 94 enters a compressor 96 to be compressed and added to the naphtha feed as recycle gas. Additionally, the gas 94 may be used as quench fluid in the hydrotreating reactor 46 and/or in the reactor effluent 50 . The sour water 88 , which contains ammonia, hydrogen chloride, and hydrogen sulfide, is removed from the separator 86 and is further processed as is known in the art. The hydrotreated naphtha is sent downstream for further processing. For example, the naphtha can be sent to a stripping column to remove hydrogen sulfide, water, and light ends. However, the hydrotreated naphtha may undergo different or additional processing without departing from the scope of the invention.
[0026] While exemplary embodiments of the process flow have been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiments merely represent an example, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those of skill in the art with a convenient road map for implementing an exemplary embodiment of the invention. It will be understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims. | In one aspect, a process for controlling a temperature of fluid entering a post treat reactor in a naphtha hydrotreater includes measuring a temperature of hydrotreater reactor effluent and determining a set point based on the measured temperature. The set point is transmitted to a first temperature indicator controller, and the first temperature indicator controller measures a temperature of fluid flowing into a post treat reactor and adjusts a combined feed flow through a bypass of an upstream combined feed exchanger. This reduces an amount of heat exchanged in the combined feed exchanger and thus prevents the fluid temperature of the fluid entering the post treat reactor from falling below the set point. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to freight vehicles and more particularly to freight vehicles having a cargo space which is capable of handling bulk goods, including bulk liquid product, as well as being capable of handling piece goods, such as boxed or palletized goods.
2. Prior Art
Freight vehicles which can handle either piece goods or bulk goods are generally known. The advantage of such convertibility is that the same cargo space on the same vehicle could handle either of these two significantly different types of loads. The term “piece goods” is defined herein to mean any goods which are handled as individual items or pieces, including packaged goods or palletized goods. The term “bulk goods” means any goods which are pourable and commonly shipped in bulk, such as powder, grain, flake, fluid or liquid materials. The term “freight vehicle”encompasses any vehicle capable of containing freight or cargo, including without limitation tractor-trailers, railway cars, ships, aircraft, domestic and I.S.O. containers, and intermodal freight vehicles.
For example, U.S. Pat. No. 4,534,596, issued Aug. 13, 1985, incorporated in its entirety by reference herein, discloses a freight vehicle having a conventional cargo space for piece goods, wherein the cargo space includes openings in the roof and floor for filling and discharging bulk material. Specially constructed bulk material container bags are deployed from the roof under the inlet openings and extend to the floor over the outlet openings. The bags are filled with bulk material through the inlet openings in the roof, and when the vehicle has arrived at the shipment destination the material is discharged from the outlet openings in the floor. To allow handling of piece goods, the bags are retractable to a stored and locked position on the ceiling of the cargo space.
Freight vehicles also are known which are capable of handling bulk liquid product. In addition to conventional tank trucks, it is known to provide conventional tractor-trailer vehicles with elongated collapsible liquid cargo bags which are adapted to be filled with liquid product. While such liquid cargo bags are secured to the cargo space of the vehicle using various securing means such as harness straps, a major problem in the transportation of bulk liquid product has been the sloshing motion of the bulk liquid during transportation. Such sloshing motion can make the vehicle difficult to control, potentially causing an accident, and additionally, can cause a vehicle to jack-knife or tip over.
The sloshing motion is caused by the kinetic energy that is generated when a large mass traveling at a given speed in a given direction is subjected to a rapid change in speed caused by acceleration or deceleration, or a sudden change in direction caused by the making of a turn. This energy when imparted to the liquid mass can build up over time as the vehicle continues on its route, potentially causing the problems discussed above. There thus exists a need in the art for improvement in systems using such bulk liquid cargo bags in convertible freight transportation vehicles.
SUMMARY OF THE INVENTION
This invention provides a freight vehicle having a cargo space convertible for handling bulk cargo as well as piece goods (general cargo), with an improved system for carrying bulk liquid material, comprising at least one collapsible, flexible liquid cargo bag deployed in the cargo space, for receiving a bulk mass of liquid product to be transported, and at least one adjustable cinch strap mounted across said bag, including a mechanism for tightening the strap down over the bag, so as to increase the pressure of liquid product within the bag such that the liquid mass within the bag acts as a solid mass. The bulk liquid is filled into the liquid cargo bag either by pumping or by gravity loading.
According to another aspect of the invention, a method is provided for carrying bulk liquid material in a freight vehicle including a cargo space convertible from a space suitable for carrying piece goods, comprising the steps of deploying at least one collapsible, flexible liquid cargo bag in the cargo space, for receiving a bulk mass of liquid product to be transported, and increasing the pressure of liquid product loaded within the bag such that the liquid mass within the bag acts as a solid mass.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more readily understood from the detailed description given hereinafter in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective phantom view of a bulk liquid cargo container system according to a first embodiment of the present invention;
FIG. 2 is a variation of the system of FIG. 1;
FIG. 3 is a perspective view of a second embodiment of the invention;
FIG. 4 is a variation of the embodiment of FIG. 3;
FIG. 5 is a perspective view of a liquid cargo container system before pressurizing, using a single-type restrainer belt;
FIG. 6 illustrates the system of FIG. 5 after pressurizing;
FIG. 7 is a perspective view of a liquid cargo container system before pressurizing, using a double-type restrainer belt;
FIG. 8 illustrates the system of FIG. 7 after pressurizing;
FIG. 9 is a detailed view of the single-type restrainer belt used in the embodiment of FIGS. 5 and 6; and
FIG. 10 is a detailed view of the double-type restrainer belt used the embodiment of FIGS. 7 and 8 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described in detail with respect to the preferred embodiments as shown in FIGS. 1-10.
As shown in FIG. 1, a bulk liquid cargo bag 12 is provided in a freight transport vehicle 10 . Bag 12 is made of a sturdy, lightweight, flexible material. Bag 12 is provided at one end thereof with a fill pipe 14 fitment for filling and draining bulk liquid product from the bag. According to the invention, a plurality of adjustable cinch straps 16 are provided for the purpose of increasing the pressure of the liquid mass within the bag 12 , such that the liquid mass will act as a solid within the bag.
The liquid mass is pressurized by tightening the straps 16 down over the bag 12 , using a ratcheting mechanism 90 , as shown in FIGS. 9 and 10. Straps 16 are preferably attached to the freight vehicle through D-rings 18 . However, it is possible that the straps 16 may be belted completely around the bag 12 , and additional harness means may be provided to harness the bag to the interior of the cargo space within the freight vehicle.
As shown in the embodiment of FIG. 1, two straps 16 are provided for a bag 12 which is on the order of 40 feet long. The straps 16 divide the bag into three equal sections. When the straps are tightened down to create a sufficient pressure in the liquid mass, they act as baffles, which serve to compartmentalize the bulk liquid into separate sections 12 a , 12 b and 12 c . These separate baffled sections prevent the transfer of the full kinetic forces from one section to another, is and serve to completely stabilize the liquid mass so that it simulates a solid mass. Tests have shown that a pressure of 3 psi was sufficient to cause the liquid mass to take on the characteristics of a solid. However, more or less pressure may be required according to the specific configuration of the bags, the density of the particular liquid product being transported, and other similar factors. This can be accomplished by varying the amount of tightening or cinching down of the straps 16 with respect to the bag 12 . A pressure meter may be attached to the bag to allow the pressure to be monitored, thus avoiding the possibility of over- or under-pressurizing the liquid mass.
In a preferred embodiment, the bag 12 may be constructed of a heavy duty, sturdy material, combined with a thinner disposable liner. The disposable liner (not shown) may be removably installed within the bag 12 through a zippered slit 20 along the length of the bag 12 . A special use leak proof, high strength zipper with disappearing teeth (commercially known) is used to close the bag. The disposable liner is removed after product discharge, and a new liner is installed before additional product is loaded into the bag. However, it is also possible according to the invention to provide a bag without a liner. Under such circumstances, it is necessary for the bag to be thoroughly cleaned before and after product loading and discharging has been performed. Such a reusable bag is constructed of FDA and Milk Industry approved flexible fabrics, with food-grade approved fitments. After unloading, the zipper is fully opened to allow the fabric to be completed washed with spinners and scrubbers, or to be commercially laundered and passed through a radiation unit to ensure sterility for the next use. Alternatively the zipper can be omitted, in which case both ends of the bag can be opened to permit the bag to be turned inside out for cleaning.
Especially where the transported product is food or plastic grade material, it is absolutely necessary to prevent adulteration or contamination. Incompatibility of many bulk products (liquid or dry) usually limits many transport vehicles to the carriage of a single commodity. Even with the use of expensive controlled cleaning systems available at approved cleaning sites, the danger of contamination still exists because of the configuration of bulk tankers. Moreover, temperature differentials between the hot water and/or steam used for cleaning and the ambient environmental temperature can result in unwanted condensation on the inside of the cargo container. Additionally, there exists potential harm or even death to personnel required to enter a tanker to perform cleaning. The use of the present invention, especially with a disposable liner, effectively eliminates these problems with the prior art.
Alternatively, as shown in FIG. 2, three straps 16 may be provided to divide the liquid mass into four compartmentalized sections, as needed to stabilize bags of longer length.
FIGS. 3 and 4 illustrate respective alternate embodiments of FIGS. 1 and 2 in which two bags 12 are provided adjacent to each other within the cargo space of a freight vehicle. This embodiment allows the transportation of two different liquid products within the vehicle, or two separate loads of the same product for two separate destinations, while maintaining the solid mass characteristics after the first load has been delivered. Additionally, the provision of two narrower bags 12 will allow greater stabilization of the liquid load than one bag of twice the width.
FIG. 5 illustrates a further alternate embodiment wherein a double fill pipe 14 a is attached to both bags 12 . The fill pipe 14 a has a single outlet port 14 c . Separate valves 14 b may be provided for each arm of the fill pipe 14 a to control loading and discharge of the liquid product. As shown in FIG. 9, one possible configuration of the cinch straps is a single strap 16 a threaded through a D-ring 18 a located between bags 12 , with a single ratcheting mechanism 90 for tightening the strap down over the bags. FIG. 6 illustrates the bags 12 in a pressurized state after tightening of the straps 16 .
FIG. 10 illustrates a second configuration of the cinch straps in which separate straps 16 b are attached to separate D-rings 18 b mounted in the floor of the cargo space between bags 12 .
FIGS. 7 and 8 illustrate an embodiment of the invention using the alternate configuration of the cinch straps as shown in FIG. 10 . FIG. 7 illustrates the bags in an unpressurized state, and FIG. 8 shows the bags in a pressurized state after tightening of the straps 16 b.
The bags 12 may be collapsed and folded when not in use and stored in a storage compartment built into the floor of the cargo space. Further, air release valves may be provided on the bags to exhaust any air volume present in the bags while loading liquid product into the bags.
The liquid cargo system according to the invention further enables an operator to access the cargo space by providing walking space between the side wall of the vehicle and the loaded liquid cargo bag—facilitating inspection, installation and removal of single or double outer bags, as well as installation and removal of disposable inner liner bags.
The invention having been thus described, it will be apparent to those skilled in the art that the same may be varied in many ways without departing from the spirit and scope of the invention. Any and all such modifications are intended to be covered by the following claims. | A freight transport vehicle convertible for carrying piece goods as well as bulk liquid cargo, includes a collapsible liquid cargo bag and at least one adjustable cinching strap for being tightened down over the bag. Tightening of the strap over the bag causes the pressure of the liquid mass within the bag to increase, serving to make the liquid mass act as a solid mass within the bag. This prevents kinetic energy that is built up in the mass through motion of the vehicle from causing sloshing motion of the liquid during transportation, thus eliminating possible hazards in operation of the vehicle and preventing possible damage to the cargo bag. | 1 |
RELATED APPLICATIONS
[0001] This application claims priority of provisional patent application No. 60/096,105 filed Aug. 10, 1998; and provisional patent application No. 60/096,104 filed Aug. 10, 1998, and provisional patent application No. 60/095,952 filed Aug. 10, 1998.
TECHNICAL FIELD
[0002] This invention relates generally to orthotic devices and more particularly to orthotic devices designed to promote an increase in range of motion in a joint by the use of selectively inflatable and deflatable bladders.
BACKGROUND OF THE INVENTION
[0003] When a joint is injured either by trauma or by surgery scar tissue can form which prevents full range of motion of that joint. Obviously, this is a disadvantageous condition and should be corrected if possible. Often, such correction involves an attempt by the injured or those assisting the injured to gradually (often over a period of months) manipulate the joint so that full range of motion is eventually achieved.
[0004] Full range of motion of a joint depends upon the anatomy of that joint and on the particular genetics of each individual. Typically, joints move in two directions, flexion and extension. Typically, flexion is to bend the joint and extension is to straighten the joint; however, in the orthopedic convention some joints only flex. For example, the ankle has dorsiflexion and plantarflexion. Other joints not only flex and extend, they rotate. For example, the elbow joint has supination and pronation, which is rotation of the hand about the longitudinal axis of the forearm placing the palm up or the palm down.
[0005] There is a need for a class of orthotics which promote an increase in range of motion of the joint rather than to merely provide support. One such series of devices is called the Joint Active System, Inc. It combines a traditional orthotic with limb cuffs on each limb segment and a special hinge joint connecting the two cuffs. This special hinge joint has a ratchet system which allows the hinge to be sequentially bent or straightened with a special wrench or knob. If the cuffs are attached to each limb segment and the hinge is slowly bent then the joint is typically forced into flexion. Similarly, if the hinge is slowly straightened after being strapped on a bent joint, the joint is also straightened. This system relies upon the patient to strap a cuff on to each limb segment. This is difficult to do particularly if the joint to be treated is the arm needed to strap the brace. Furthermore, the pressure on each limb segment by each cuff is very painful as the joint is bent or straightened. Lastly, the ratchet system does not allow for instant release of the pressure used to force an increase in the range of motion.
[0006] Another series of devices is made by Dynasplint Inc. These devices are similar to the Joint Active System in that there is a cuff for each limb segment and a special hinge designed to promote an increase in range of motion. With the Dynasplint system, the hinge contains a special set of springs that, when tightened, will put a low load of pressure on the cuffs to bend or straighten. The same objections apply to the Dynasplint as they do to the Joint Active System. The cuffs are uncomfortable, the device is hard to put on and there is no instant release of the pressure. With this system the device must be worn for hours at a time to be effective.
[0007] There are other devices available which use inflatable bladders around a joint. They tend to use the bladder(s) to provide support across the joint. Such inflatable bladders are positioned across the joint or in near proximity to the joint.
[0008] Such conventional orthosis devices may be designed for support across a joint. In general an orthosis connects one limb segment to another across a joint. The connection is either a rigid member or a hinged joint. In this way orthotics work to support the joint as a means of protecting it. General reference is made to U.S. Pat. Nos. 5,542,911, 5,378,224, 5,348,530, and 5,730,710.
[0009] One particular device which uses the bladder(s) to provide support across the joint is also shown in U.S. Pat. No. 5,514,081 to Mann, which uses the inflatable bladder to cross the elbow joint to provide support for an elbow with a flexion contracture (the elbow joint can not fully extend). This device places the inflatable bladder across the joint so that when it inflates it holds the elbow in full extension. This device does not appear to include rigid structural members. Further, it does not isolate the bladder distant to the joint, thus maximizing the biomechanical forces across the joint for promoting elbow extension.
[0010] U.S. Pat. No. 3,581,740 has an air bladder which crosses multiple finger joints of a hand as well as the wrist. Upon inflation, the hand is moved to a normally extended, spaced apart, condition.
[0011] Some prior art patents use inflatable members to gain range of motion in the hand. U.S. Pat. No. 4,671,258 uses a cyclical therapeutic joint exerciser by inflating a pouch that crosses the joint and a spring steel insert that automatically bends the joint when the inflatable pouch is not inflated. U.S. Pat. No. 4,807,606 uses bladders around the joints in the hands to exercise the joints. That is to say, the bladders are inflated and deflated sequentially with a pump device to flex and extend hand joints.
[0012] U.S. Pat. No. 5,056,504 uses the inflatable bladder in the palm against a rigid structure to push the fingers into extension. However, this 5,056,504 patent includes a bladder which “crosses the joint”, which is not only potentially painful to the user if the joint has undergone surgery, but is not optimally biomechanically efficient in the distribution of forces as will be described later with respect to applicant's invention.
[0013] Therefore, it may be seen that there is a need in the art to provide an improved orthotic device, which can be used to straighten (“orthoun” means to straighten) limbs or joints.
[0014] Therefore, it may be seen that there is a need in the art for an orthotic device and method of using same which provides optimal biomechanical distribution of load.
SUMMARY OF THE INVENTION
[0015] The present invention overcomes deficiencies in the prior art by providing an improved orthotic device. Generally described, the present invention comprises a strap, an inflatable member including an inflatable bladder, the inflatable member being spaced from the joint, and a device for inflating and deflating the inflatable member such that as the inflatable member is inflated, the strap is placed in increasing tension and the joint is moved.
[0016] More particularly described, the present invention comprises a structural body portion, an inflatable member, a flexible strap configured to be attached intermediate the structural body portion and the inflatable member, and an inflating device for inflating the inflatable member so that it increases in size, such that as the inflatable member is inflated, the inflatable member tend to push against the limb such that the limb is urged towards said structural body portion and the joint is moved. Other inventions are also included.
[0017] It is a further object of the present invention to provide an orthotic device which provides an optimal biomechanical application and distribution of load.
[0018] It is a further object of the present invention to provide an improved orthotic device which is easy to use.
[0019] It is a further object of the present invention to provide an improved orthotic device which is simple to manufacture.
[0020] It is a further object of the present invention to provide an improved orthotic device which applies no direct pressure on the joint itself.
[0021] It is a further object of the present invention to provide an improved orthotic device which is cost-effective to manufacture and use.
[0022] It is a further object of the present invention to provide an improved orthotic device which is efficient in its use of forces.
[0023] It is a further object of the present invention to provide an orthotic device which has increased reliability.
[0024] It is a further object of the present invention to provide an orthotic device which is easy to apply and remove.
[0025] It is a further object of the present invention to provide an orthotic device which allows for instant release of pressure.
[0026] It is a further object of the present invention to provide an orthotic device which provides a high load application
[0027] It is a further object of the present invention to provide an orthotic device which provides an efficient load application.
[0028] It is a further object of the present invention to provide an orthotic device which applies comfortable pressure.
[0029] It is a further object of the present invention to provide an improved orthotic device which is light in weight and easy to transport.
[0030] It is a further object of the present invention to provide an improved orthotic device which can be used in conjunction with a crutch for structural support.
[0031] Other objects, features, and advantages of the present invention will become apparent upon reading the following detailed description of the preferred embodiment of the invention when taken in conjunction with the drawing and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] [0032]FIG. 1 is a front view of a knee extension assembly 10 and ankle support member 30 used in conjunction with a conventional crutch 12 .
[0033] [0033]FIG. 2 is a is a side view of the elements 10 , 12 , being used by a wearer 15 .
[0034] [0034]FIG. 3 is a top cross-sectional view taken transverse to the longitudinal axis of the crutch and the wearer's leg of FIG. 2, with the cross-section taken through the inflatable air bladder 22 and its containing pouch 24 .
[0035] [0035]FIG. 4 is another transverse cross-section taken from the FIG. 1 configuration, but this time the cross-section is taken just above the ankle support member 30 .
[0036] [0036]FIG. 5 shows a front view of a second embodiment 200 of the invention, being an arm orthotic device.
[0037] [0037]FIG. 6 is a side view of a third embodiment 300 of the present invention, being an orthotic device for extending the forearm relative to the upper arm from position P 1 to position P 2 .
[0038] [0038]FIG. 7 is an exploded, illustrative, view of the device 300 of FIG. 7, with the portion comprised of the straps 325 and the inflatable member 324 (which includes an air bladder within a fabric pouch) detached from the main body of the device 300 .
[0039] [0039]FIG. 8 is a front view of a fourth embodiment of the invention, being an apparatus 400 used in conjunction with a user 415 , to provide external rotation of the shoulder.
[0040] [0040]FIG. 9 is a top view of some of the elements of FIG. 8.
[0041] [0041]FIG. 10 is a top view of a fifth embodiment of the present invention, being a device 500 which provides external rotation of the shoulder in a different range.
[0042] [0042]FIG. 11 is a front view of a sixth embodiment of the present invention, being a device 600 which provides abduction of the shoulder.
[0043] [0043]FIG. 12 is a side view of a seventh embodiment of the present invention, being a device 700 for flexion of the elbow.
[0044] [0044]FIG. 13 is a side view of an eighth embodiment of the present invention, being a device 800 which promotes both dorsiflexion and plantarflexion alternately and continuously.
[0045] [0045]FIG. 14 is a side view of a ninth embodiment of the present invention, being a device 900 which provides dorsiflexion of the ankle joint by capturing the foot and using the inflatable member to pull the ankle into dorsiflexion. This apparatus 900 includes a substantially flat base 901 , an inflatable member 920 , and an including floating yoke member 930 which captures the foot as described in further detail below.
[0046] [0046]FIGS. 15 and 16 are rear elevational and top plan views, respectively, of portions of the device of FIG. 14.
[0047] [0047]FIG. 17 is a side view of a tenth embodiment of the present invention, being a device 1000 which provides dorsiflexion of the ankle joint by capturing the foot and using the inflatable member 1020 to pull the ankle into dorsiflexion. This device 1000 includes a substantially rigid structural member 1001 which resembles a open-backed “slipper” portion 1002 with a front vertical flange 1003 which extends upwardly from the top of the slipper portion and along the front of the shin of the wearer 1015 .
[0048] [0048]FIG. 18 is a side view of an eleventh embodiment of the present invention, being another orthotic device 1100 which can be used to provide dorsiflexion of the ankle. This device 1100 includes a base 1101 , a cuff 1102 fixed to the base, a selectively positionable foot plate 1103 , an inflatable member 1120 , and connecting straps 1125 .
[0049] [0049]FIG. 19 is an illustrative view 1200 of a pair of exemplary limb members (such as an upper and lower leg, or such as an upper and lower arm), and how such members can be captured by the “three point” force configuration described above. Such an inventive configuration provides an optimally efficient biomechanical application of force by positioning the inflatable member as far as possible from the pivoting point, whether that pivoting point be the joint ( as shown in the FIG. 6), or the interface between the limb and the structural member (see FIG. 2).
[0050] [0050]FIGS. 20 and 21 are pictorial and end views, respectively, of a forearm supination and pronation device 1300 which includes a base 1301 , right and left adjustable base flanges 1302 L, 1302 R, respectively, an inflatable member 1320 , straps 1325 , a retaining cuff 1327 , and a glove assembly 1350 including a thumb retainer 1351 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0051] Reference is now made to the Figures, in which like elements indicate like elements throughout the several views.
[0052] The application will be discussed by reference to several different embodiments, which may share inventive concepts or alternately may each include individual inventive concepts.
[0053] First Embodiment, FIGS. 1 - 4
[0054] [0054]FIG. 1 is a front view of a knee extension assembly 10 and an ankle support member 30 used in conjunction with a conventional crutch 12 . FIG. 2 is a is a side view of the elements 10 , 12 , 30 being used by a wearer 15 . FIG. 3 is a top cross-sectional view taken transverse to the longitudinal axis of the crutch and the wearer's leg of FIG. 2, with the cross-section taken through the inflatable air bladder. FIG. 4 is another transverse cross-section taken from the FIG. 1 configuration, but this time the cross-section is taken just above the ankle support member 30 .
[0055] The crutch as shown in FIG. 1 is a conventional type of crutch, which is a distinctive aspect of the present invention in that conventional crutches are readily available within the market. The present invention particularly adds the use of a knee extension assembly 10 and an ankle support member 30 .
[0056] The knee extension assembly 10 includes an inflatable member 20 , a plurality of straps 25 , and a conventional hand-operated pump 24 with a bleed valve 29 . The inflatable member 20 can include an inflatable bladder 22 contained within a fabric pouch 24 . The inflatable bladder 22 can, as in other configurations described herein, may be inflated by the conventional hand-operated pump 24 and deflated by use of the bleed valve 29 . The plurality of straps 25 as shown in FIG. 2 can position the leg between the inflatable member and the crutch, while containing and attaching the inflatable member relative to the crutch. The configuration shown in FIGS. 1 - 2 includes three straps. However, other strap or bladder configurations may be used as known in the art.
[0057] The ankle support member 30 includes a cradle portion 32 and a back portion 34 is attached to the crutch towards the lower end of the crutch by use of conventional fasteners such as 36 , although any suitable attachment of the ankle support member 30 to the crutch is suitable. The cradle portion 32 defines a generally upwardly (as FIG. 4 is viewed) cradle which is configured to accept a length of the leg of the user.
[0058] Upon inflation of the inflatable member inflatable member 20 , it may be understood that a “three point” force combination is provided which allows for effective extension of the knee by use of an optimal, highly efficient but comfortable biomechanical application of load. This three point contact configuration is illustrated in FIG. 2 by the force arrows “F 1 ”, “F 2 ”, and “F 3 ”. Force arrow “F 1 ” illustrates force provided upwardly on the leg by the ankle support member 30 . The force arrow “F 2 ” illustrates force provided downwardly on the leg atop the thigh of the leg by the inflatable member 20 of the knee extension assembly 10 . It may be understood that this force is translated to the crutch through tension in the straps 25 . The force arrow “F 3 ” illustrates force provided upwardly on the leg by the upper end of the crutch (which may be the padded underarm rest). This three point action is further described elsewhere in this application with reference to FIG. 19.
[0059] It should be understood that although FIG. 2 illustrates the use of the air bladder atop the thigh, alternate locations of the air bladder are likewise contemplated; the inflatable bladder could alternatively be placed upon the knee, or the tibia. However, the present invention contemplates adjustability of the location of the knee extension assembly 10 along the length of the crutch, as at times (for example at the beginning of treatment) the knee joint may be sensitive to contact, and thus the knee extension assembly 10 may be adjusted so it is atop the thigh. At the same time, biomechanically the knee is a desirable location for application of the load, so later in treatment, when the knee is not as tender, the knee extension assembly 10 may be adjusted so it is atop or at least closely adjacent the knee.
[0060] Under one configuration of the present invention, the ankle support member 30 will remain at least temporarily attached to the crutch during its normal use. The patient can use the crutch in the conventional manner, with the assembly 10 carried therewith on the crutch if so desired. When an orthotic session is desired, the patient will then typically sit on a chair with the upper (underarm) portion of the crutch positioned beneath the relevant buttock. The remainder of the elongate crutch is positioned relatively underneath the length of the patient's leg, with the ankle support member 30 portion being positioned under the patient's ankle. The device 10 is then attached to its position as shown in FIG. 2, and the adjustable straps are adjusted to a comfortable tension. The bladder is then filled as desired, with pressure relief being available as desired.
[0061] The straps are adjusted to provide some initial amount of pressure, with the final amount of pressure and resulting force being provided by the air. It should also be understood that the adjustability of the straps accommodates various knee positions; it should be understood that during the initial stages of recovery, the leg may not be able to be bent very much at the knee, whereas towards the end of the recovery period, the leg preferably may be bent substantially straight at the knee.
[0062] It should be understood that one portion of the present invention includes the use of straps including hook-and-loop (such as VELCRO) attachment which allow for a “take-up” feature; this feature allows for the combination of large motions of the limb. However, other take-up configurations may be used such as known in the art, such as friction or other buckles, without departing from the spirit and scope of the present invention. This applies throughout this discussion.
[0063] As noted above, the knee extension assembly according to the present invention is contemplated for use in conjunction with a conventional crutch member such as known in the art and conventionally available. It should be understood that such a crutch configuration could also be a special crutch specially configured to work with the orthotic device according to the present invention, or could simply be a straight board or other elongate structural member.
[0064] Second Embodiment—FIG. 5
[0065] [0065]FIG. 5 illustrates the use of a rigid plastic or other suitable material, to provide an elongate structural member 210 which may be attached to the underside of the arm, with its lower end extending beyond the elbow, terminating in a “free end”. Approximate this “free end” are attached three (as shown) straps 225 which connect an inflatable member 220 (an air bladder in a fabric pouch) to the free end of the elongate member. This member 220 is configured to be positioned adjacent to the forearm of a wearer, such that inflation of the air bag therein tends to provide pressure causing movement such as shown as M. This is conventionally called “extension” and is desired in certain types of orthotics.
[0066] It should be understood that this FIG. 5 configuration includes the “three point” force combination as described above. However, this FIG. 5 configuration is similar to the FIG. 6 and 7 configuration, and the “three point” force configuration will be described in more detail in reference to FIG. 6.
[0067] Third Embodiment—FIGS. 6 and 7
[0068] [0068]FIGS. 6 and 7 show a third embodiment of the present invention, being an apparatus 300 configured to be attached to the arm of a wearer 315 . It should be understood that FIG. 6 is a more simplified version.
[0069] The apparatus 300 includes a substantially rigid structural frame 301 including a forearm bearing portion 302 and an upper arm bearing portion 304 , connected by one or more connecting members 306 . Also included are straps 325 and an inflatable member 320 , which can include an inflatable bladder contained by a fabric pouch. As are other configurations discussed herein, the straps are sewn to the fabric pouch by conventional means. As elsewhere in this discussion VELCRO-type attachments at 327 may be provided for detachability and adjustability of the straps.
[0070] Flanges 305 (see FIG. 7) may be optionally used if desired to extend upwardly on either side of the main body to contain the forearm as desired.
[0071] [0071]FIG. 7 shows the embodiment in slightly more detail than FIG. 6. In FIG. 7, the forearm bearing portion 302 , the upper arm bearing portion 304 , and two connecting members 306 are shown; it may be understood that in the FIG. 7 version shown they are all part of an essentially one-piece frame which in the preferred embodiment is plastic. It should be understood that the upper arm bearing portion is contoured to conform somewhat to the upper surface of the upper arm for comfort purposes when bearing downwardly thereon.
[0072] The frame 301 of the apparatus can be plastic, wood, metal, a metal/fabric sling, or other material(s) suitable to provide the needed structural support. It should be understood that the members 302 and 305 of the frame 301 could be rigidly attached together by virtue of being part of an integral, one-piece unit, or alternately could be part of a multiple-part device which allows for relative adjustment between the members 302 , 304 as desired.
[0073] As shown in FIG. 6, it may be seen that the “three point” force configuration is again utilized in this embodiment, as shown by force arrows “F 1 ”, “F 2 ” and “F 3 ”. Force arrow “F 3 ” illustrates the force down by the inflatable member. Force arrow “F 2 ” illustrates the force up by forearm bearing portion 302 . Force arrow “F 1 ” illustrates the force down by upper arm bearing portion 304 .
[0074] It should be understood that during the initial stages of recovery, the elbow may not be able to accommodate much pressure, and for that reason the elbow may be placed off the forearm bearing portion 302 . However, towards the end of the recovery period, the elbow may be placed on the forearm bearing portion 302 for optimal biomechanical application of force.
[0075] Fourth Embodiment—FIGS. 8 and 9
[0076] [0076]FIGS. 8 and 9 show an apparatus 400 which may not include any substantially rigid members (although one against the stomach may be used), but includes the use of an inflatable member 424 and a pair of straps 425 U, 425 L (upper and lower), together which are configured to provide external rotation of the shoulder. The upper strap 425 U may be passed around the upper torso and arm of a user, leaving the opposite arm free. The lower strap 425 L may be provided around the lower torso of the wearer, such as would a conventional belt. Between the upper and lower straps are attached an inflatable member 424 (being a bladder within a pouch), having its upper edge attached to the upper strap, and its lower edge attached to the lower strap, with the air bladder therein configured to be inflated and deflated as noted before.
[0077] To utilize the apparatus, the forearm is placed adjacent the air bladder, and the upper strap 425 U is provided in a suitably taut configuration to keep the relevant upper arm against the wearer's side for optimal biomechanical effect. The air bladder is then inflated, causing external rotation of the shoulder. As may be understood, when desired, the air bladder may be deflated as needed, in order to remove the device, or in order to alleviate pain.
[0078] It should be understood that other configurations are also contemplated for maintaining the upper arm against the side of the user, such as but not limited to a cuff (not shown) to contain the arm but allow it to rotate as it is strapped to the body.
[0079] Fifth Embodiment—FIG. 10
[0080] As shown in FIG. 10, the two-strap apparatus as shown in FIG. 7 may be complimented with a foam block or wedge 550 to provide a range of motion of external rotation which is different from the range of motion provided in the apparatus shown in FIGS. 8 and 9.
[0081] In this configuration, the forearm is oriented generally forwardly, and along the conventional line of sight of the user/patient 515 , and the inflatable member 524 is located between the foam member and the forearm. It should also be noted that the foam block 550 could be a separate air bag 550 , which could be inflated to a desired size and temporarily sealed.
[0082] Internal rotation could further be provided, by use of additional straps 525 A and an additional inflatable air member 524 A (shown in dotted line) to provide movement towards the body. These straps 524 A would have one of their ends attached to the air bladder, and their other ends attached relative to the patient's body, preferably at about the right shoulder.
[0083] Therefore, internal and external rotation could be provided by the use of a pair of bladders as desired “IR” and “ER”.
[0084] It should be understood that the configurations described above which include the two oppositely located bladders may be used to provide “CPM”, otherwise known as continuous passive motion.
[0085] Sixth Embodiment—FIG. 11
[0086] [0086]FIG. 11 illustrates a sixth embodiment 600 of the present invention, including a pair of horizontally-oriented straps 625 U, 624 L, an upper strap 624 U located about the upper torso and approximate the armpit region, and the lower strap 625 L being strapped about the lower torso of the body slightly upwardly of the belt region. Between the two straps is supported a foam pad, which fits generally underneath the armpit region of a particular arm of the wearer 615 . An inflatable member 624 is located intermediate the underneath of the upper arm and the foam pad, such that inflation of the air bladder by the air pump 628 by the wearer 615 causes abduction of the shoulder. Although not shown, it should also be understood that a second inflatable member (not shown), with accompanying straps, could be used to cause movement in the opposite direction. A third shoulder-to-crotch strap 626 extends to underneath the groin region could also be used in order to provide support for pulling the scapula downwardly. This isolates motion to the glenohumeral joint (otherwise known as the arm/shoulder blade joint) as opposed to the acronmioclavicular joint.
[0087] Seventh Embodiment—FIG. 12
[0088] This embodiment of the invention comprises a device 700 which uses a substantially rigid structural member 701 , an inflatable member 724 , and straps 725 which connect the structural member 701 to the inflatable member 724 . An additional hand strap 740 is provided to discourage movement of the inflatable member from its shown position to a position more towards the elbow. Another set of conventional straps such as 750 may be used to attach the structural member 701 relative to the upper arm.
[0089] As may be understood, by inflating the inflatable member 724 , the straps 725 are drawn into tension and flexion of the elbow joint is provided.
[0090] Eighth Embodiment—FIG. 13
[0091] [0091]FIG. 13 relates the use a orthotic device 800 which include the use of alternating air flow to respective air bladders to cause range of motion in, for example, an ankle. This is referred to as providing “continuous passive motion”.
[0092] The device includes a hard shell boot 810 , within which the lower leg, ankle, and foot of a patient is inserted. Two air bladders 824 U, 824 L, (although additional bladders could be used), are included within the boot. One air bladder is located above the foot proximate the toe area, whereas the other air bladder is located beneath the sole of the foot proximate the toe area. The “upper” bladder 824 U is separate from the “lower” bladder 824 L, and the upper and lower bladders can be inflated and deflated separately, in order to provide an up and down motion of the foot, translating into an up and down motion of the ankle.
[0093] At least two types of flexion are intended to be provided under the present invention. These two types of flexion are plantarflexion, and the other type is dorsiflexion.
[0094] In an alternate embodiment of the present invention, two hinged flaps are also used within the boot cavity, one atop the foot and below the upper bladder, and the other below the foot and above the lower bladder. These two flaps correspond to the two bladders, such that inflation of the lower bladder pushes upwardly on the lower pivoting flap, causing upper flexion (dorsi) flexion, and increased air within the upper bladder, creates downward movement of the upper flap, causing the opposite type of flexion.
[0095] The two bladders are connected by two corresponding air lines, each of which are attached at their opposite ends to a common air source. Under one configuration of the present invention, the lines are alternatively filled and evacuated, causing the dual motion desired under the present invention.
[0096] Ninth Embodiment—FIGS. 14 - 16
[0097] This apparatus 900 includes a substantially flat base 901 , an inflatable member 920 , and a floating yoke member 930 . The substantially flat base 901 includes a pair of upwardly-directed holes 902 (as FIG. 14 is viewed) which slidably accept a corresponding pair of downwardly-directed feet 911 which extend downwardly and leftwardly at an incline from the inclined yoke plate 910 .
[0098] Straps 925 are attached intermediate the upper end of the inclined yoke plate 910 and the inflatable member 920 . A vertical anchor strap 935 is connected intermediate the upper end of the inclined yoke plate 910 and the base plate 901 .
[0099] The inclined yoke plate 910 includes a tonguelike pad at 950 to provide a cushion as described below for the upper side of the foot. The tonguelike pad at 950 is located at the top of the yoke and can act as a type of “tramoline” pushing on the dorsum of the foot with a cushioning effect.
[0100] An air pump 990 with a quick release valve 991 is also included to inflate and deflate the air bladder within the fabric pouch of the inflatable member 920 .
[0101] Such a yoke concept accommodates different sized feet, as a variety of feet can be slipped into the gap defined by angled yoke plate.
[0102] After the straps are properly adjusted to take out slack, the air pump 990 is used to inflate the inflatable member 920 , tensioning the straps and providing a force on the calf of the leg of the wearer. This causes the ankle into desired dorsiflexion.
[0103] The downwardly-directed feet 931 do not bottom out in the holes 902 , but instead are allowed to slide or “float” upwardly and downwardly therein. Since the straps are in tension, it may be understood that a force is applied to the top of the foot by the angled yoke plate 930 at the location of the tonguelike pad at 950 . This causes the foot to be maintained in place due to pressure of the yoke atop the foot, instead of allowing the heel of the foot to lift from its location atop the base plate 901 . A heel cup or stop 909 also may be used as shown in dotted line in FIG. 16.
[0104] The spherically shaped member 950 is configured to allow the base plate 901 to be put on a level supporting surface such as a floor surface such that the spherically shaped member 950 can provide a rolling pivot or rocking point about which the base plate 901 can rotate. This conveniently allows the lower leg to be maintained in a substantially consistent orientation while the forces within the apparatus cause the ankle of the foot into desired dorsiflexion. This can be quite convenient as it allows the user/patient to sit comfortably while undergoing the process.
[0105] Tenth Embodiment—FIG. 17
[0106] This device 1000 includes a substantially rigid structural member 1001 which resembles a open-backed “slipper” portion 1002 with a front vertical flange 1003 which extends upwardly from the top of the slipper portion and along the front of the shin of the wearer 1015 . The wearer's front foot may be placed in the cavity of the slipper portion 1002 , and an inflatable member 1020 may be placed behind the calf. This inflatable member is attached relative to the upper, free, end of the front vertical flange 1003 by one or more straps 1025 .
[0107] After initial adjustment of the straps 1025 , the inflatable member may be inflated by use of the air pump, causing the straps to be drawn into tension, and the calf to be pulled forward. This causes desired dorsiflexion of the ankle.
[0108] An optional strap at 1035 may be used to maintain the foot in place.
[0109] The spherically shaped member 1009 of the substantially rigid structural member 1001 is configured to allow the substantially rigid structural member 1001 to be put on a level supporting surface such as a floor surface such that the spherically shaped member 1009 can provide a rolling pivot or rocking point about which the substantially rigid structural member 1001 can rotate. This conveniently allows the lower leg to be maintained in a substantially consistent orientation while the forces within the apparatus cause the ankle of the foot into desired dorsiflexion. As noted above this can be quite convenient as it allows the user/patient to sit comfortably while undergoing the process.
[0110] It should be understood that this configuration 1000 may be used instead or in combination with the FIG. 14 configuration, if the yoke of FIG. 14 applies too much pressure.
[0111] Eleventh Embodiment—FIG. 18
[0112] [0112]FIG. 18 shows another orthotic device 1100 which can be used to provide dorsiflexion of the ankle. This device 1100 includes a base 1101 , a cuff 1102 fixed to the base, a selectively positionable foot plate 1103 , an inflatable member 1120 , and connecting straps 1125 .
[0113] The selectively positionable foot plate 1102 is mounted to the base 1101 via a pivotable connection as known in the art, which allows for initial adjustment. However, it should be understood that when the orthotic device 1100 is in use, the pivoting connection is fixed such that the foot plate 1103 is fixed relative to the base 1101 .
[0114] The cuff 1102 is fixed to the base, and allows for the lower leg of the wearer 1115 to slide therein as described below.
[0115] After initial adjustment of the foot plate 1102 and the straps 1125 , the inflatable member 1125 is inflated, causing the straps to be drawn into tension. The inflatable member 1125 pushes down on the leg, namely the anterior aspect of the distal thigh, with the kneed flexed approximately 90 degrees. This causes the lower leg to move downwardly while being contained by the cuff 1102 . This forces the ankle into dorsiflexion as the foot of the wearer bears against the foot plate 1103 . Pressure may be relieved as desired.
[0116] [0116]FIG. 19
[0117] [0117]FIG. 19 is an illustrative view 1200 of a pair of exemplary limb members (such as an upper and lower leg, or such as an upper and lower arm), and how such members can be captured by the “three point” force configuration described above. Such a configuration provides an optimally efficient biomechanical application of force by positioning the inflatable member as far as possible from the pivoting point, whether that pivoting point be the joint (as shown in the FIG. 6), or the interface between the limb and the structural member (see FIG. 2).
[0118] Such a combination of the “three point” force configuration, the inflatable member, tensioning straps, and structural member is submitted to be a significant improvement over the prior art as pressure is not provided across the joint, as might be provided by a simple “wrap” or the known cited art.
[0119] [0119]FIGS. 20, 21
[0120] [0120]FIGS. 20 and 21 are pictorial and end views, respectively, of a forearm supination and pronation device 1300 . This device 1300 includes a base 1301 , right and left adjustable base flanges 1302 L, 1302 R, respectively, an inflatable member 1320 , straps 1325 , a retaining cuff 1327 , and a glove assembly 1350 including a thumb retainer 1351 .
[0121] The base 1302 is configured to be stationary and to provide support for the other members.
[0122] The right and left adjustable base flanges 1302 L, 1302 R, respectively, are configured to the attached to the base, and to be adjustable. During use they are rigidly affixed relative to the base 1302 .
[0123] The straps 1325 are positioned intermediate one of the base flanges and the rigid post member 1350 .
[0124] The rigid post member 1350 is attached to the glove assembly 1340 . This attachment can be temporary through VELCRO, snaps, or even a clothespin configuration. Alternately the post 1350 could be pivotally attached to the plate 1301 .
[0125] The glove assembly 1340 can be attached to a user's hand by various means, but the invention contemplates the insertion of the hand into the glove assembly, which is snugged as desired by use of various straps or bands. The glove assembly includes a thumb retainer 1351 perpendicular to the longitudinal axis of the forearm.
[0126] By selectively adjusting the flanges and the straps supination and prontation of the forearm may be provided, while the glove twists atop the base plate 1301 .
[0127] Although a glove assembly is disclosed above, it should be understood that the present invention also contemplates use of the device without a glove assembly. Such contemplation includes the use of some other means for attaching the post to the arm such that the longitudinal axis of the post is substantially parallel to the plane of the palm of the hand. Such an alternate configuration includes a strap which can fit around the hand across the palm and around the back of the hand, or a “clip” which can attach to the hand, or a “thumb sock”, which can be used to contain the thumb relative to the post. However, it should be understood that for optimal biomechanical effect the thumb should be oriented generally alongside and parallel to the elongate post.
Options, Variations
[0128] It should also be understood that different fluids other, than atmospheric air may be used, such as water, etc. Alternatively, hot or cold fluids, which may provide some therapeutic value, may likewise be used.
[0129] Various straps as known in the art may be used in order to maintain the outer boot in place on the wearer's limb.
[0130] It should be understood that under an alternative configuration according to the present invention, in order to provide an improved mechanical advantage, a boot may be used with a bent leg (providing an exposed upper horizontal surface) may be used. In such a configuration, the boot would include a strap which would go up and over the top of the knee, which is advantageous especially when providing the dorsi-type flexion of the ankle.
[0131] It should also be understood that the provision of air to the bladders according the present invention could be provided by automatic means, which may be advantageous in a long term type of treatment, such as the use of periodic inflation and deflation throughout a night time of wearing.
[0132] Furthermore, manual inflation and deflation for the provision of specific stretching of tissues may be provided by manual inflation and deflation of one of the bladders.
[0133] Finally, it may be understood that is not necessary that two bladders be used during a particular orthotic session; only one bladder may be used if only one type of motion is desired to stretch the limb against muscle tension.
Miscellaneous Comments
[0134] As noted above, a structural member may be used to provide structural support for various of the orthotic devices discussed herein. Such a structural device could be made of plastic, wood, metal, a metal/fabric sling, or other material(s) suitable to provide the needed support. It should be noted that although the structural support will need some type of stiffness to provide its support, it does not have to be perfectly rigid; some bending or deflection is possible and may be desirable.
Conclusion
[0135] Therefore it may be seen that the present invention provides a plurality of devices which provide improvements over known prior art othrotic devices.
[0136] While this invention has been described in specific detail with reference to the disclosed embodiments, it will be understood that many variations and modifications may be effected within the spirit and scope of the invention as described in the appended claims. | An inflatable bladder position a distance from a joint is attached to an external structural support which crosses the joint but does not support it. By inflating the bladder one limb segment is forced towards the external support thereby increasing the ranges of motion of that joint. Further, the inflatable bladder has an instant release valve which, when pressed, will instantly release the pressure within the bladder. The limb is positioned intermediate the bladder and the external structural support for optimal biomechanical efficiency. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to catheters used with guide wires in the cardiovascular system and, in particular, to a system for facilitating exchange of such catheters and guide wires, and for transporting such catheters and guide wires to selected sites within a patient.
BACKGROUND OF THE INVENTION
[0002] Catheters are inserted to various locations within a patient for a wide variety of purposes and medical procedures. For example only, one type of catheter is used in percutaneous catheter intervention (PCI) for the treatment of a vascular constriction termed a stenosis. In this instance, the catheter has a distally mounted balloon that can be placed, in a deflated condition, within the stenosis, and then inflated to dilate the narrowed lumen of the blood vessel. Such balloon dilation therapy is generally named percutaneous transluminal angioplasty (PTA). The designation PTCA, for percutaneous transluminal coronary angioplasty, is used when the treatment is more specifically employed in vessels of the heart. PTCA is used to open coronary arteries that have been occluded by a build-up of cholesterol, fats or atherosclerotic plaque. The balloon at the distal end of the catheter is inflated, causing the site of the stenosis to widen.
[0003] The dilation of the occlusion, however, can form flaps, fissures and dissections, which may result in reclosure of the dilated vessel or even perforations in the vessel wall. Implantation of a stent can provide support for such flaps and dissections and thereby prevent reclosure of the vessel or provide a patch repair for a perforated vessel wall until corrective surgery can be performed. A stent is typically a cylindrically shaped device formed from wire(s) or a tube and is intended to act as a permanent prosthesis. Stents may include therapeutic coatings or deliver therapeutic drugs to further treat the vessel and prevent reclosure of the vessel. A stent is deployed in a body lumen from a radially compressed configuration into a radially expanded configuration that allows it to contact and support a body lumen. A stent can be implanted during an angioplasty procedure by using a balloon catheter bearing a compressed stent that has been loaded onto the balloon. The stent radially expands as the balloon is inflated, forcing the stent into contact with the body lumen, thereby forming a supporting relationship with the lumen walls. Alternatively, self-expanding stents may be deployed with a sheath-based delivery catheter. Deployment is effected after the stent has been introduced percutaneously, transported transluminally and positioned at a desired location by the delivery catheter. In addition to angioplasty and stenting procedures, other therapeutic procedures require use of a delivery catheter, such as drug delivery, filters, occlusion devices, diagnostic devices and radiation treatment.
[0004] Typically, the placement of such therapeutic delivery catheters involves the use of a guide wire, which may be inserted into the patient's vasculature through the skin, and advanced to the location of the treatment site. The delivery catheter, which has a lumen adapted to receive the guide wire, then is advanced over the guide wire. Alternatively, the guide wire and the delivery catheter may be advanced together, with the guide wire protruding from the distal end of the delivery catheter. In either case, the guide wire serves to guide the delivery catheter to the location to be treated.
[0005] To treat small diameter vessels remote from the entry point into the patient, a guide catheter is used to span the distance. For example, in PTCA or stent delivery, a guide catheter 10 is typically inserted into a large artery 12 near the patient's groin, and then advanced toward the heart 14 to the entry opening, or ostium, of the diseased coronary artery as illustrated in FIG. 1A. The guide catheter 10 provides a tubular conduit through which catheters and guide wires, designated generally as 16 , can be passed from outside the patient to the vessel being treated.
[0006] There are three general types of catheters: “over-the-wire” (OTW) catheters, “rapid exchange” (RX) or single operator catheters and “fixed wire” (FW) or “a balloon on a wire” catheters. An over-the-wire catheter comprises a guide wire lumen that extends the entire length of the catheter. The guide wire is disposed entirely within the catheter guide wire lumen except for the distal and proximal portions of the guide wire, which extend beyond the distal and proximal ends of the catheter respectively. An OTW catheter typically has a “co-axial” catheter construction, as shown in FIGS. 2A and 3A, wherein two hollow tubes are nested together such that the lumen 22 of the inner tube can slidably receive guide wires, such as guide wire 24 , and the annular luminal space 26 formed between the inner and outer tubes is used for inflation/deflation, fluid. An alternative “multilumen” OTW catheter construction has an elongate shaft made from a single extruded tube 18 having two lumens 22 ′ and 26 ′ formed side-by-side, as shown in FIGS. 2B and 3B. OTW catheters that contain both multilumen segments and coaxial segments are also known.
[0007] Over-the-wire catheters have many advantages traceable to the presence of a full-length guide wire lumen such as good stiffness and pushability for readily advancing the catheter through the tortuous vasculature and across tight stenoses. The full-length guide wire lumen permits removal and replacement of a guide wire in an indwelling catheter, as may be required to alter the shape of the guide wire tip. It is also sometimes desirable to exchange one guide wire for another guide wire having a different stiffness. For example, a relatively soft, or flexible guide wire may prove to be suitable for guiding a PTCA catheter through a particularly tortuous anatomy, whereas following up with a stent-delivery catheter through the same vasculature region may require a guide wire that is relatively stiffer. The full-length guide wire lumen is also available for transporting radiocontrast dye to the stenosed artery, for making pressure measurements, for infusing drugs and for other therapies.
[0008] Over-the-wire catheters do suffer some shortcomings, however. For example, it often becomes necessary, in the performance of a PCI, to exchange one indwelling catheter for another catheter. In order to maintain a guide wire in position while withdrawing the catheter, the guide wire must be gripped at its proximal end to prevent it from being pulled out of the blood vessel with the catheter. For example, a PTCA catheter, which may typically be on the order of 135 centimeters long, is longer than the proximal portion of the standard guide wire that protrudes out of patient. Therefore, exchanging an over-the-wire PTCA catheter requires an exchange guide wire of about 300 centimeters long, whereas a standard guide wire is about 165 centimeters long.
[0009] In one type of over-the-wire catheter exchange, the standard length guide wire first is removed from the lumen of the indwelling catheter. Then, a longer exchange guide wire is passed through the catheter to replace the original wire. Next, while holding the exchange guide wire by its proximal end to control its position in the patient, the catheter is withdrawn proximally from the blood vessel over the exchange guide wire. After the first catheter has been removed, the next OTW catheter is threaded onto the proximal end of the exchange guide wire and is advanced along the exchange guide wire, through the guiding catheter, and into the patient's blood vessels until the distal end of the catheter is at the desired location. The exchange guide wire may be left in place or it may be exchanged for a shorter, conventional-length guide wire. In an alternative type of catheter exchange procedure, the length of the initial guide wire may be extended by way of a guide wire extension apparatus. Regardless of which exchange process is used, the very long exchange guide wire is awkward to handle, thus requiring at least two operators to perform the procedure.
[0010] Catheter designs have been developed in an attempt to eliminate the need for guide wire extensions or exchange guide wires. One such catheter design is the rapid exchange (RX) type catheter. Catheters of this type are formed so that the guide wire is located outside of the catheter except for a short guide wire lumen that extends within only a comparatively short distal segment of the catheter. The rapid exchange catheter's proximal exit port for the guide wire is typically located about 5 cm (2.0 in) to 100 cm (11.8 in) proximal to the catheter's distal end. In use, the guide wire is placed initially in the patient's vascular system. The distal segment of the RX catheter then is threaded onto the wire. The catheter can be advanced alongside the guide wire with its distal segment being attached to and guided along the guide wire. The RX catheter can be removed and exchanged for another RX catheter without the use of a very long exchange guide wire and without requiring withdrawal of the initially placed guide wire.
[0011] Although an RX catheter system may avoid the requirement for using a very long exchange wire, it presents several difficulties. First, without a full-length guide wire lumen, the proximal shaft of an RX catheter lacks an OTW catheter's coaxial interrelationship with the guide wire, which provides optimal transmission of force to push the distal end of the catheter through tight stenoses and/or tortuous blood vessels. FIGS. 2A and 3A illustrate guide catheter 10 , a shaft segment of OTW catheter 18 extending there through, and guide wire 24 disposed within guide wire lumen 22 in the common construction of coaxial tubes. The nested tubes result in an inner guide wire lumen 22 and an annular inflation lumen 26 formed between the tubes. The coaxial interrelationship with guide wire 24 provides an optimal transmission of force along the catheter length. In FIGS. 2B and 3B, inflation lumen 26 ′ extends parallel to guide wire lumen 22 ′ in a side-by-side arrangement. Although guide wire lumen 22 and guide wire 24 ′ are located off-center in catheter 18 ′, guide wire 24 ′ is confined within catheter 18 ′ throughout its length. Even if catheter 18 ′ begins to buckle slightly when the distal tip of the catheter is being forced through a tight stenosis, there is very little misalignment with guide wire 24 ′, such that most of the push force is transmitted to the distal tip. Therefore, despite their disadvantages during catheter exchange procedures, OTW catheters remain popular in the United States, due in part to the coaxial alignment between the catheter shaft and the guide wire, and the resulting excellent pushability of the device.
[0012] While improvements to RX catheters have incorporated stiff, metal proximal shafts and axial overlap between the shaft and the guide wire lumen to overcome the deficiencies discussed above, such RX catheters still are not optimal. FIGS. 4 and 5 depict prior art RX catheter 30 incorporating such a reinforced shaft 32 , disposed over guide wire 34 within guide catheter 36 . However, even with continuous column support of reinforced shaft 32 , the non-aligned or offset arrangement of guide wire 34 and shaft 32 of catheter 30 can cause shaft buckling within the guiding catheter, as illustrated generally at 38 in FIG. 4, especially when the distal tip of the catheter is being forced through a tight stenosis. Such a non-coaxial misalignment causes displacement of push forces and an associated resistance to catheter advancement, especially in the region of proximal guide wire port 40 .
[0013] A second difficulty associated with RX catheters is that it is not possible to exchange guide wires in an indwelling RX catheter, as can be done advantageously with OTW catheters. A guide wire can be withdrawn, sometimes unintentionally, from the proximal guide wire port, thus derailing an indwelling RX catheter. However, neither the first guide wire, nor a replacement guide wire, can be directed back into the catheter's proximal guide wire port, which is hidden remotely in the guiding catheter within the patient. FIG. 6 illustrates the problem of blindly steering the tip of guide wire 42 within guiding catheter 44 in an attempt to find and engage proximal guide wire port 46 of RX catheter 48 .
[0014] A third difficulty associated with RX catheters is that, if the guide wire lumen is so short that the proximal guide wire port exits from the distal end of the guiding catheter, then the guide wire will be exposed. Such an RX device presents a risk of what is called the “cheese cutter effect,” which is damage to the delicate inner surface of a curved artery from straightening tension applied to the exposed guide wire during push-pull maneuvers to advance the catheter. The short-lumen RX device also presents an increased risk of guide wire entanglement in those procedures where multiple guide wires are used, because the guide wires are exposed within the blood vessel. Furthermore, the exposed, unprotected portion of the guide wire can become kinked or tangled within the patient's vessel, adding complications to the procedure.
[0015] A fourth difficulty associated with RX catheters is encountered at the proximal end of the catheter system. There, the RX catheter and the guide wire extend from the guiding catheter side-by-side, making it awkward to seal the system against blood loss during manipulation of the components. The sealing, or “anti-backbleed” function is typically accomplished with a “Tuohy-Borst” fitting that has a manually adjustable gasket with a round center hole that does not conform well to the side-by-side arrangement of a catheter shaft and guide wire. A final difficulty associated with RX catheters is that the lack of a full-length guide wire lumen deprives the clinician of an additional lumen that may be used for other purposes, such as pressure measurement, injection of contrast dye distal to the stenosis, or infusing a drug.
[0016] An over-the-wire catheter designed to eliminate the need for guide wire extensions or exchange wires is disclosed in U.S. Pat. No. 4,988,356 (Crittenden et al.). This over-the-wire/short wire (OTW/SW) catheter includes a catheter shaft having a cut that extends longitudinally between the proximal end and the distal end of the catheter and that extends radially from the catheter shaft outer surface to the guide wire lumen. A guide member slidably coupled to the catheter shaft functions to open the cut such that the guide wire may extend transversely into or out of the cut at any location along its length. By moving the guide member, the effective over-the-wire length of the OTW/SW catheter is adjustable.
[0017] When using the OTW/SW catheter, the guide wire is maneuvered through the patient's vascular system such that the distal end of the guide wire is positioned across the treatment site. With the guide member positioned near the distal end of the catheter, the proximal end of the guide wire is threaded into the guide wire lumen opening at the distal end of the catheter and through the guide member such that the proximal end of the guide wire protrudes out the proximal end of the guide member. By securing the guide member and the proximal end of the guide wire in a fixed position, the catheter may then be transported over the guide wire by advancing the catheter toward the guide member. In doing so, the catheter advances through the guide member such that the guide wire lumen envelops the guide wire as the catheter is advanced into the patient's vasculature. In a PTCA embodiment, the OTW/SW catheter may be advanced over the guide wire in this manner until the distal end of the catheter having the dilatation balloon is positioned within the stenosis and essentially the entire length of the guide wire is encompassed within the guide wire lumen.
[0018] Furthermore, the indwelling OTW/SW catheter may be exchanged with another catheter by reversing the operation described above. To this end, the indwelling catheter may be removed by withdrawing the proximal end of the catheter from the patient while holding the proximal end of the guide wire and the guide member in a fixed position. When the catheter has been withdrawn to the point where the distal end of the cut has reached the guide member, the distal portion of the catheter over the guide wire is of a sufficiently short length that the catheter may be drawn over the proximal end of the guide wire without releasing control of the guide wire or disturbing its position within the patient. After the catheter has been removed, another OTW/SW catheter may be threaded onto the guide wire and advanced over the guide wire in the same manner described above with regard to the OTW/SW catheter. The OTW/SW catheter not only permits catheter exchange without the use of the very long exchange guide wire and without requiring withdrawal of the initially placed guide wire, but it also overcomes many of the other difficulties discussed in association with RX catheters.
[0019] Despite these advantages, original OTW/SW catheters in accordance with the '356 patent had difficulties related to movement of the guide wire through the guide member. As disclosed in the '356 patent, the use of a hypodermic tubing member to direct a guide wire into and out of the guide wire lumen was found to be effective while the guide wire was stationary within the guide member, and while the catheter was moved therethrough. However, if the guide wire were to be withdrawn through the guide member, the hypodermic tubing member would often scrape pieces of a lubricious coating from the guide wire. The resulting shavings, designated generally as 50 in FIG. 7, would become jammed in the annular space between the guide wire 52 and the hypodermic tubing member 54 , preventing further movement of the guide wire.
[0020] In a more significant problem with the original OTW/SW catheter, it could fail to adequately contain the guide wire within the guide wire lumen during normal operation. In particular, as the catheter was advanced over the guide wire, the catheter could bend or buckle such that the guide wire could protrude from the catheter shaft. If the guide wire protruded from the catheter shaft, it could subsequently become pinched, and the distal end of the guide wire could be pulled out of or pushed beyond the treatment site, thus complicating the procedure and requiring repositioning within the patient's vasculature. Bending or buckling of a OTW/SW catheter could also occur proximal to the guide member, where the guide wire is absent from the guide wire lumen. Furthermore, the transition between the proximal shaft containing the longitudinal cut and the distal part of the catheter is also a potential kink location. It is among the general objects of the invention to provide an improved device that overcomes the foregoing difficulties.
SUMMARY OF THE INVENTION
[0021] The present invention is a catheter and guide wire exchange system comprising an elongate flexible catheter having proximal and distal ends and first and second lumens extending there through, the first lumen being open at the shaft distal end and being sized and shaped to slidably receive a guide wire. The second lumen is an inflation lumen. The catheter has a bitumen proximal shaft and a coaxial distal shaft. The distal and proximal shafts are coupled through a transition section. At the transition section, an outer tubular portion of distal shaft overlaps the outer surface of the proximal shaft distal end. Proximal end of distal shaft inner tubular member is positioned within the first lumen of the proximal shaft. The shafts are then fused forming the transition section.
[0022] A guide member is mounted on catheter proximal shaft and is received in a guide way formed from a longitudinal cut in catheter proximal shaft to enable transverse access to the first lumen through the elongate flexible catheter. The guide way extends along a major portion of the length of the proximal shaft from a location adjacent the proximal end of the catheter to a location proximal to the proximal shaft distal end. A stop is located on the exterior of the proximal shaft distal end proximal to the transition section. The guide member cannot travel distally past the stop. An elongate stiffening member is disposed within the second lumen from the catheter proximal shaft to a location past the guide way distal end through the transition section and into the catheter distal shaft. A balloon is mounted about catheter distal segment, the balloon being in fluid communication with the second lumen. The guide member has a catheter passageway for slidably receiving the catheter shaft and a guide wire passageway for slidably receiving the guide wire. The guide member merges the guide wire and the catheter by guiding the guide wire transversely through the guide way in the catheter and into the first lumen. Conversely, the guide member can be used for separating the guide wire and catheter by guiding the guide wire transversely out of the first lumen through the guide way. The guide wire lumen may further include a ramp or recess to assist in aligning the guide wire with the guide wire passageway.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where:
[0024] [0024]FIG. 1A is a diagrammatic illustration of a patient showing the manner in which a balloon catheter is advanced from the femoral artery through the aorta and into the patient's heart;
[0025] [0025]FIG. 1B is an enlarged portion of FIG. 1A showing the present invention positioned with the guide catheter and extending into the femoral artery;
[0026] [0026]FIG. 2A is a longitudinal sectional illustration of a section of a prior art coaxial over-the-wire catheter and guide wire system;
[0027] [0027]FIG. 2B is a longitudinal sectional illustration of a section of a prior art multilumen over-the-wire catheter and guide wire system;
[0028] [0028]FIG. 3A is a transverse sectional illustration of a coaxial prior art over-the wire catheter and guide wire system, taken along the line 3 A- 3 A of FIG. 2A;
[0029] [0029]FIG. 3B is a transverse sectional illustration of a multilumen prior art over the-wire catheter and guide wire system, taken along the line 3 B- 3 B of FIG. 2B;
[0030] [0030]FIG. 4 is a longitudinal sectional illustration of a section of a prior art rapid exchange catheter and guide wire system;
[0031] [0031]FIG. 5 is a transverse sectional illustration of a prior art rapid exchange catheter and guide wire system, taken along the line 5 - 5 of FIG. 4;
[0032] [0032]FIG. 6 is partial longitudinal sectional illustration of a section of a prior art rapid exchange catheter and guide wire system, shown within a guiding catheter;
[0033] [0033]FIG. 7 is a partial longitudinal sectional illustration of a section of a prior art OTW/SW catheter and guide wire system;
[0034] [0034]FIG. 8 is an illustration of the catheter and guide wire of the present invention in an assembled configuration;
[0035] [0035]FIG. 8A is a cross-section taken along line A-A of FIG. 8;
[0036] [0036]FIG. 8B is a cross-section taken along line B-B of FIG. 8A;
[0037] [0037]FIG. 8C is a cross-section taken along line C-C of FIG. 8A;
[0038] [0038]FIG. 8D is a cross-section taken along line D-D of FIG. 8A;
[0039] [0039]FIG. 9 is a transverse sectional illustration of the transition section of the present invention;
[0040] [0040]FIG. 10A is a large view of the present invention extending from the guide catheter at the ostium of the heart;
[0041] [0041]FIG. 10B is a cross-section of the guide catheter showing the present invention extending through the aortic arch of FIG. 1A;
[0042] FIGS. 11 A- 11 C are schematic illustrations of the construction of the stop member of the present invention;
[0043] FIGS. 12 A- 12 E are schematic illustrations of the construction of the transition section of the present invention;
[0044] [0044]FIG. 13 is a transverse sectional illustration of an alternative embodiment of the transition section of the present invention;
[0045] [0045]FIG. 14 is a transverse cross-sectional view of the guide member of the present invention;
[0046] FIGS. 15 A- 15 C show the guide member positioned on the proximal shaft and illustrating the inter-relation between the guide member and the proximal shaft;
[0047] [0047]FIG. 16 is an alternative embodiment of the transition section with a ramped guide wire lumen; and
[0048] [0048]FIG. 17 is a second alternative embodiment of the transition section with a recessed guide wire lumen.
DETAILED DESCRIPTION OF THE INVENTION
[0049] As shown in FIG. 8A, the invention includes a catheter, indicated generally by the reference character 100 , on which a guide member 102 is slidably mounted. Guide wire 104 is illustrated as extending through the guide member 102 . Guide member 102 serves as a juncture in which the catheter 100 and guide wire 104 may be merged or separated so that the portion of guide wire 104 which extends proximally of guide member 102 (to the left as seen in FIG. 8A) is separated from catheter 100 and the portion of guide wire 104 which is located distally of guide member 102 (to the right as seen in FIG. 8A) is contained and housed within catheter 100 except for distal end 106 of guide wire 104 which may protrude distally out of distal end 108 of catheter 100 .
[0050] Catheter 100 includes an elongate, flexible, cylindrical main body, which may be formed from an extruded plastic material such as, for example, polyethylene or polyethylene block amide (PEBA) copolymer. Catheter 100 has a distal shaft 110 and a proximal shaft 112 with a transition section designated 114 . The embodiment shown in FIG. 8A, a catheter, such as for PTCA or stent delivery, having balloon 116 mounted around the catheter body near the distal end 108 of catheter 100 . Balloon 116 may be inflated and deflated through inflation lumen 118 formed through the body of the catheter 100 . Inflation lumen 118 extends from the proximal end of catheter 100 , where it communicates with fitting 120 and extends the length of catheter 100 , terminating in communication with the interior of balloon 116 . Fitting 120 may be connected to a suitable source of pressurized fluid or a partial vacuum (not shown) to inflate or deflate balloon 116 . Catheter 100 includes lumen 122 for receiving guide wire 104 . Guide wire lumen 122 extends the full length of catheter 100 , terminating at distal end 108 and proximal fitting 120 .
[0051] In accordance with the invention, the body of proximal shaft catheter 100 is formed with longitudinal guide way 124 which, when catheter 100 is viewed in cross-section, as in FIG. 8A, may be considered as defining a pair of flaps 126 and 128 which normally close together at guide way 124 to define enclosed guide wire lumen 122 . Guide wire lumen 122 may be circular in cross-section or may be non-circular; in either case, the cross-sectional dimensions of guide wire lumen 122 are greater than the cross-sectional dimension of guide wire 104 to permit relative longitudinal movement between guide wire 104 and catheter 100 . Inflation lumen 118 encompasses elongate stiffening member 130 , which causes the shaft of catheter 100 to have greater bending stiffness than guide wire 104 . Stiffening member 130 extends at least through the length of catheter 100 that includes guide way 124 , thus preventing the shaft from bending such that guide way 124 could buckle allowing guide wire 104 to protrude from the catheter shaft and it may extend into distal shaft 110 . Guide way proximal end 132 may terminate at or near fitting 120 . In the embodiment shown in FIG. 8A, guide way distal end 136 terminates short of proximal shaft distal end 138 , thereby leaving distal section 140 of proximal shaft 112 in which guide wire lumen is defined by a continuous surrounding wall as shown in FIG. 8B. Stop 142 is located approximate guide way distal end 136 . Stop 142 is a raised portion on the proximal shaft as seen in FIG. 8A. The raised portion may be annular or multiple areas spaced around the shaft circumference such as the two raised areas 162 and 164 spaced 180 degrees apart on the long axis of oval proximal shaft 112 as shown in FIG. 1C.
[0052] Turning now to FIGS. 8B, 8C and 9 , catheter 100 transforms from its proximal side-by-side lumen configuration to a distal coaxial configuration adjacent guide way distal end 136 . Distal catheter shaft 110 preferably comprises a coaxial arrangement of two tubes 144 and 146 , with inner tube lumen 148 communicating with proximal shaft guide wire lumen 150 . Outer tube 146 encompasses the inner tube 144 , forming an annular lumen 152 that extends proximal inflation lumen 154 to balloon 116 . The length of catheter 100 is such that it can pass easily through the curved aortic arch as shown in FIGS. 10A and 10B. In these views, guide catheter 156 stops proximate the ostium of the heart and prior to the diseased coronary artery. Guide catheter 156 provides tubular conduit through which catheter 100 and guide wire 104 are passed through the patient from outside the patient to the vessel being treated, as illustrated in FIGS. 1A, 1B, 10 A and 10 B. As seen in FIG. 10B, transition section 114 is proximal of guide catheter opening 158 with distal shaft 110 extending out from guide catheter 156 .
[0053] Prior to forming the transition section 114 , stop 142 is formed on proximal shaft 112 as is seen in FIGS. 11 A-C. Preferably, a tubular member 160 , preferably made of polyethylene or other suitable material that may be fused with the proximal shaft, is placed over proximal shaft distal section 138 , as shown by the arrows A and B, and positioned proximate guide way distal end 136 as seen in FIG. 11A. Heat, designated by the arrows A, B and C in FIG. 11B, is applied to fuse tubular member 160 to proximal shaft 112 . As is well known to those of skill in the art, heat can be applied by any suitable heat source such as a hot air source or a laser source. By fusing the tubular member 160 onto generally proximal shaft 112 , preferably two raised areas 162 and 164 spaced on opposing exterior surfaces of proximal shaft 112 are formed creating stop 142 as shown in FIG. 11C. Additionally, an annular raised surface may be formed about the exterior surface of proximal shaft 112 such as shown in FIG. 8. Stop 142 increases the outer diameter of proximal shaft 112 by an amount sufficient to prevent guide member 102 from moving distally past stop 142 . Alternatively, stop 142 may be formed integrally with proximal shaft 112 when it is initially extruded or tubular member 160 may be secured with an adhesive as will be understood by those of skill in the art.
[0054] Turning now to FIGS. 9 and 12A- 12 E, the formation of transition section 114 will be described. As shown, proximal shaft portion 164 adjacent guide wire lumen 150 is cut with an angle to assist in the assembly of catheter 100 . Distal shaft inner tube 144 is inserted into proximal shaft guide wire lumen 150 as shown by arrow A. Proximal shaft 112 contains stiffening member 166 that is preferably a hypotube that has a spiral cut section 168 to assist in forming a smooth transition from proximal shaft 112 to distal shaft 110 . Hypotube distal section 170 extends from proximal shaft inflation lumen 154 and is inserted into distal shaft inflation lumen 152 as indicated by arrow B. Outer tube proximal end 172 is positioned to overlap proximal shaft distal end 146 as indicated by arrows C and D. The amount of overlap is preferably the minimal such as 3 to 6 mm. Mandrels (not shown) are inserted into guide wire and inflation lumens 148 , 150 , 152 and 154 to prevent closure of the lumens during application of heat, represented by arrows E-H, to form transition bond 174 as shown in FIG. 12D. While any appropriate heat source may be used, application of laser heat is preferred for a forming a fusion bond that is minimal in size to avoid creating a potential kink point in the catheter while also being fluid tight and able to withstand the necessary pressures in a procedure. Alternatively, other bonding methods may be used such as use of an adhesive. FIG. 12E illustrates the path of guide wire through guide wire lumens 148 and 150 forming overall catheter guide wire lumen 122 , designated by arrows 176 a - d , and likewise arrows 178 a - dc illustrate the pathway of the inflation fluid through lumens 152 and 154 forming overall catheter inflation lumen 118 .
[0055] [0055]FIG. 13 shows an alternative embodiment for transition section 114 that incorporates a connecting tube 180 . In this embodiment, proximal shaft 112 may be formed from a commonly used catheter material, such as polyethylene. Distal shaft outer tube 146 may likewise be formed from a polyethylene or multilayer extrusion that has an inner layer that readily fuses with the material of proximal shaft 112 . Inner tube 144 distal shaft 110 may be made from a commonly used catheter mutilayer extrusion having a nylon or polyamide block copolymer outer layer, a polyethylene inner layer and an intermediate tie layer. The nylon or polyamide block copolymer outer layer of inner tube 144 will not readily bond to the polyethylene of proximal shaft 112 . Connecting tube 180 is preferably made of polyethylene and is used to assist in bonding tube 144 with the surface of inflation lumen 150 to form a fluid tight seal necessary for the integrity of overall catheter inflation lumen 118 . Distal end 182 is inserted into proximal end 184 of inner tube 144 and the tubes are bonded or fused together to form a fluid tight seal. Proximal end 186 is inserted into distal end 188 of inflation lumen 150 and proximal end 190 of outer tube 146 is inserted over distal end 192 of proximal shaft 122 . The bonding process to form transition section 114 can then proceed as described with respect to FIGS. 12 A- 12 E.
[0056] Guide member 102 has proximal and distal ends 200 and 202 , respectively, as shown in FIGS. 14 and 15A- 15 C. Catheter passageway 204 extends longitudinally in a generally straight line from guide member proximal end 200 to guide member distal end 202 . Guide wire passageway 206 extends from its end 208 through tube 210 into guide wire lumen 122 at its end 212 . Guide wire tube 210 is preferably made of polyimide. Catheter proximal shaft 112 extends through catheter passageway 204 , engaging keel 214 , which extends through guide way 124 in catheter 100 to spread flaps 126 and 128 apart as shown in FIGS. 15 A- 15 C. Guide wire 104 extends through guide wire tube 210 that enters guide wire lumen 122 through spread-apart flaps 126 and 128 . During advancement of catheter 100 through guide member 102 , flaps 126 and 128 draw together under the influence of the inherent resiliency of the catheter body to close guide way 124 , thus enclosing guide wire 102 within guide wire lumen 122 . Guide wire 104 is contained within guide wire lumen 122 from guide member 102 to catheter distal end 108 . Guide wire 104 may be inserted or removed through guide wire tube 210 , while guide member 102 is held stationary with respect to catheter 100 as shown by the arrows A and B in FIG. 15A. In this fashion, guide wire 104 can be exchanged within catheter 100 . In yet another type of manipulation, guide member 102 can be held relatively still while catheter 100 is moved through catheter passageway 204 , thus bringing guide wire 104 and catheter 100 apart or together, depending on which direction catheter 100 is moved as indicated by arrow A in FIG. 15B.
[0057] In an alternative embodiment shown in FIG. 16, guide wire lumen 122 may include a ramp 220 approximate the distal position of guide wire tube distal end 212 . Ramp 220 assists in aligning guide wire 104 into the guide wire passageway 206 as guide wire 104 is back loaded into catheter 100 . In a back-loading operation, guide wire 104 is inserted into catheter distal end 108 and threaded proximally through guide wire lumen 122 until guide wire passageway distal end 212 captures the proximal end 222 of guide wire 104 and directs it into guide wire passageway 206 . This procedure is typically performed while guide member 102 is positioned adjacent guide way distal end 136 . Guide wire passageway distal end 212 may be positioned to be coaxial with guide wire lumen 122 . In the guide wire back loading procedure, guide wire 104 may move along lower surface 224 of guide wire lumen 122 and move against lower edge 226 of tube 210 instead of moving into guide wire passageway 206 . Ramp 220 acts to assist in aligning guide wire passageway distal end 212 with guide wire proximal end 222 by preventing it from moving against lower edge 226 of tube 210 in order to complete the “back-loading” operation. Ramp 220 may be formed during the extrusion process or by adding the ramp prior to forming the transition section. Alternatively, the ramp may be formed as a part of process for forming the stop or transition section by selecting an appropriate mandrel selected for the guide wire lumen that will permit formation of the ramp.
[0058] [0058]FIG. 17 shows another embodiment of guide wire lumen 122 which includes a recess 228 approximate the distal position of guide wire passage way distal end 212 . Recess 228 has distal and proximal sloped surfaces 230 and 232 . Recess 228 assists in aligning guide wire 104 with guide wire passageway 206 as guide wire 104 is back loaded into catheter 100 . In a back-loading operation, guide wire 104 can be inserted into and threaded proximally through guide wire lumen 122 until guide wire proximal end 222 reaches recess 224 . Distal and proximal surfaces 230 and 232 are selected such that if as guide wire proximal end 222 is threaded proximally it is received in recess 228 , the sloped surfaces will direct guide wire 104 into guide wire passageway 206 when guide member 102 is positioned adjacent guide way distal end 136 . Recess 228 may be formed by removing material prior to the bonding process for the stop or the transition section. Alternatively, an appropriately designed mandrel may be used to form the recess during the heating process for either the formation of the stop or transition section.
[0059] While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made there in without departing from the spirit and scope of the invention. | A catheter and guide wire exchange system including a catheter that has a guide wire lumen with a guide way extending along a length of the proximal shaft. A guide member is slidably disposed about the proximal shaft for directing a guide wire into or out of the guide way and the guide wire lumen. A transition section joins the bitumen proximal shaft to a coaxial distal shaft. | 0 |
BACKGROUND
This invention relates to an improved tubing hanger and running tool with a preloaded lockdown of the tubing hanger to the wellhead housing which overcomes the disadvantages of prior subsea tubing hangers and running tools.
Tubing hangers are typically designed to support the weight of the associated tubing strings by landing on a seat within the wellhead housing. The tubing hanger is then locked in position by urging a split ring carried on the tubing hanger body into a recess in the wellhead housing interior wall which prevents upward movement of the tubing hanger. Due to manufacturing tolerances and debris which may have accumulated on the landing seat in the wellhead housing during prior drilling operations, it has been necessary to make the recess which the split ring engages longer than the split ring. This additional length allows room for the tubing hanger and split ring to reciprocate within the recess as the tubing string lengths grow or contract due to thermal stresses.
Once the running tool is removed from the tubing hanger and wellhead, residual torsional force exerted on the tubing hanger by the tubing strings suspended below can cause the tubing hanger to rotate with respect to the wellhead housing and move from its original orientation. This loss of orientation can damage or make it impossible to reinstall the running tool during subsequent tubing string operations or install the subsea tree subsequently. As drilling and production technology has allowed such operations in deeper water depths, operators have insisted on the use of metal-to-metal seals to seal the annulus between the tubing strings and the last casing string. These type of metal-to-metal seals are easily damaged by excessive movement after energization. The reciprocating and rotational motions described above are extremely deleterious to these metal-to-metal seals. The present invention overcomes these problems by providing a novel apparatus for preloading the tubing hanger and preventing reciprocating or rotational movement of the tubing hanger.
U.S. Pat. No. 3,693,714 to B. F. Baugh discloses a typical prior art tubing hanger and running tool which utilizes an expansible lock ring to secure the tubing against upward movement with respect to the wellhead housing.
U.S. Pat. No. 4,067,062 to B. F. Baugh is an example of a tubing hanger allowing use of multiple tubing strings and an associated hydraulic running tool which can run and lock the tubing hanger within the wellhead and is releasable therefrom. The running tool can be subsequently reconnected to the tubing hanger and hydraulically unlatch the tubing hanger and retrieve it to the surface.
U.S. Pat. No. 4,067,388 to E. M. Mouret discloses a running tool and tubing hanger combination which allows release of the tool from the tubing hanger by hydraulic pressure or rotation of the running string to which the tool is attached.
SUMMARY
An improved subsea tubing hanger having a body with an external shoulder for landing on a seat within a subsea wellhead housing, locking means carried on the hanger to engage a interior recess of the wellhead housing, with the locking means including a locking ring and a actuator ring for setting the locking ring. A preloading means includes a extendible ring cooperating with the locking ring to prevent any movement of the tubing hanger when engaged and operable by torque supplied by the running tool. The improved tubing hanger running tool includes a body secured to the tubing hanger by conventional latching means with a rotatable outer sleeve having an interior helical groove. A piston positioned on the running tool body and operated by hydraulic fluid pressure has an exterior pin which coacts with the helical groove to provide torque to the actuating ring and preloading means of the tubing hanger.
An object of the present invention is to provide an improved tubing hanger and running tool for lowering, landing and locking a tubing hanger within a subsea wellhead housing and preloading the lockdown mechanism to prevent any subsequent axial or rotational movement of the tubing hanger and its metal-to-metal seals relative to the wellhead housing.
Another object of the present invention is to provide an improved tubing hanger running tool which provides torque for operating the improved preload lockdown mechanism without transmitting the torque into the tubing hanger or its metal-to-metal seals.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present invention are set forth below and further made clear by reference to the drawings, wherein:
FIG. 1 is an elevation view, in full section, of the preferred embodiment of the improved tubing hanger and running tool with the tubing hanger in the locked position and the preload mechanism activated.
FIG. 2 is an enlarged elevation view of the tubing hanger landed in the wellhead housing with the running tool omitted for clarity prior to energizing of the metal-to-metal seal.
FIG. 3 is a view similar to FIG. 2 with the metal-to-metal seal energized.
FIG. 4 is a view similar to FIG. 3 with the tubing hanger lockdown engaging the internal recess of the wellhead housing and the tubing hanger preload activated.
FIGS. 5A, 5B, 5C, 5D and 5E are views similar to FIG. 1 on an enlarged scale showing the wellhead housing, tubing hanger and running tool in greater detail with the FIGURES arranged left to right, with FIG. 5A being the leftmost and FIG. 5E being the rightmost.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, subsea tubing hanger TH has been lowered on running tool RT into position within subsea wellhead W. Casing hanger CH has been previously landed within wellhead W and annulus packoff assembly AS installed thereabout. A collet connector, blowout preventer stack and riser (not shown) are secured to the upper end of wellhead W in a manner well known to those skilled in the art with the riser extending to the surface for connection to a drilling rig (not shown) for drilling and production operations within the wellhead. Running tool RT has orienting sleeve S forming the upper end thereof with orientation slot OS formed therein for cooperation with an orienting pin (not shown) disposed in the bore of the blowout preventer to provide an orientation reference with respect to wellhead W.
Referring to FIG. 2, wellhead W includes wellhead housing 10 with casing hanger CH landed therein having landing seat 12 therein for receiving shoulder 14 of tubing hanger TH. Casing hanger CH has upper face 16 with antirotation slot 18 formed therein for receiving antirotation pin 20 of tubing hanger TH. Wellhead housing 10 has locking recess 22 formed on its interior above casing hanger CH for coaction with tubing hanger TH as hereinafter described.
Tubing hanger TH includes body 24 with tubing passages 26 therethrough with only one of such passages being shown and lower ring 28 secured thereon having shoulder 14 sized to land within casing hanger CH on landing seat 12. Shoulder ring 30 is secured to the exterior of body 24 with camming ring 32, metal-to-metal seal 34, bearing ring 36 and retainer ring 38 which is also secured to body 24 therebelow. Landing ring 40 is positioned about shoulder ring 30 with antirotation pins 20 disposed in its lower face. Piston ring 42 is positioned above landing ring 40 and keyed together by suitable means, as shoulder screws 44. Immediately above piston ring 42 are torque ring 48 and lockdown backup ring 50 connected by thread 52. The lower end of torque ring 48 has tabs 54 which engage vertical slots 56 in piston ring 42 to prevent rotation therebetween while allowing relative axial movement. The interior and exterior of torque ring 48 and lockdown backup ring 50 have seals disposed thereon which seal against body 24 and piston ring 42 to form controlled landing chamber 58 which is connected by passage 60 to check valve 62 and operated by running tool RT in a manner to be described hereinafter.
Lock ring 64 is initially positioned on the exterior of lockdown backup ring 46 and has tapered inner surface 66 which is engaged by tapered surface 68 on actuator ring 70 to urge lock ring 64 into engagement with locking recess 22 of wellhead housing 10. Actuator ring 70 is of two part construction to facilitate assembly with lower slot 72 engaged by torque pins 74 to allow axial movement of actuator ring 70 with respect to lockdown backup ring 50 and transmitting torque thereto. Torque slots 76 are positioned on the upper face of actuator ring 70 for engagement by running tool RT. Protector ring 78 is held in position immediately above lock ring 64 on torque pins 74 to prevent premature activation of ring 78 during running.
The upper face of tubing hanger body 24 is counterbored with latch groove 80 positioned therein for connection of running tool RT. Orientation slot 82 is vertically oriented in body 24 for engagement by running tool RT in a manner well known to those skilled in the art.
Referring to FIGS. 5A-5E, running tool RT includes lower body 84, upper body 86 and orientation body 88 with lower body 84 and upper body 86 held in abutting relationship by two part piston nut 90. Control passages 92c-92g extend through lower body 84 and upper body 86 with seal subs 94 providing a continuous fluid path. Control passages 92a-92e are shown radially arranged for descriptive purposes but are actually arranged radially and circumferentially to fit within bodies 84 and 86. Lower body 84 and upper body 86 are maintained in proper orientation by seal subs 94. Upper body 86 and orientation body 88 are connected by nut assembly 96 with orientation pins 98 maintaining alignment. Orientation body 88 has orienting sleeve S secured thereto and terminates with handling sub 100.
Torque sleeve 102 is held on running tool RT by bearing ring 104 and is rotatable thereon with splines 106 formed on the lower end thereof for engagement with torque slots 76 of actuator ring 70. Helical groove 108 is formed on the interior of torque sleeve 102 with pin 110 of torque piston 112 guided therein. Torque piston 112 is antirotated with respect to upper body 86 by key 114 axially movable within vertical slot 116. Torque piston 112 has interior and exterior seals disposed thereon which seal against upper body 86 and torque sleeve 102 to form torque chamber 118 which receives hydraulic fluid pressure through control passage 92a. Piston nut 90 has interior and exterior seals disposed thereon which seal against upper body 86 and torque sleeve 102 to form untorque chamber 118 which receives hydraulic fluid pressure through control passage 92b. When hydraulic fluid pressure is supplied through control passages 92a or 92b, torque piston 112 is constrained to move up or down accordingly. Simultaneously, pin 110 is moving in helical groove 108 thereby causing torque sleeve 102 which is free to rotate on upper body 86, to transmit its torque through torque slots 76 and splines 106 to actuator ring 70. Actuator ring 70 transmits this torque through torque pins 74 to lockdown backup ring 50. Since torque ring 48, piston ring 42, and landing ring 40 are antirotated with respect to casing hanger CH, lockdown backup ring 50 is urged upwardly to contact lock ring 64 and establish the desired preloaded connection.
Piston stop ring 120 is positioned axially below piston nut 90 and secured on lower body 84. Locking piston 122 is disposed radially outwardly from piston stop ring 120 and is of two part construction to facilitate assembly. Interior groove 124 of locking piston 122 receives unlocking segments 126 therein with latching piston 128 closely fitting behind unlocking segments 126 to ensure their retention within groove 124. Piston nut 90, piston stop ring 120 and locking piston 122 have seals disposed thereon which seal against lower body 84 and torque sleeve 102 to form tubing hanger locking chamber 130 and tubing hanger unlocking chamber 132 which receive hydraulic fluid pressure from control passages 92c and 92d, respectively.
Similarly, piston stop ring 120, locking piston 122 and latching piston 128 have seals disposed thereon which seal against lower body 84 to form running tool latching chamber 134 and running tool unlatching chamber 136 which receive hydraulic fluid pressure from control passages 92e and 92f, respectively. Running tool latch ring 138 is disposed on the lower portion of running tool RH and is cammed into engagement with latch groove by latching piston 128 as described hereinafter. Ring 140 is positioned immediately above latch ring 138 and prevents premature actuation of latch ring 138 during running and retrieving of the running tool RT. Orientation key 142 is secured to the lower end of body 84 and coacts with orientation slot 82, as best seen in FIG. 2, to duplicate alignment of tubing passages 26 when running tool RT is inserted in tubing hanger TH. Control passage 92g extends through running tool RT and aligns with control valve 62 when running tool RT is inserted in tubing hanger TH. Tubing sub 144 is positioned in tubing passage 26 of running tool RT and extends into corresponding tubing passage 26 of tubing hanger TH. Adjacent orientation key 142 is poppet valve 146 to which control passages 92c and 92h are connected and which coacts with actuator ring 70 in a manner to be described hereinafter to provide a surface indication of positive locking of the tubing hanger TH at the surface.
A typical sequence of events for using the improved tubing hanger and running tool with a preloaded lockdown is as follows. The tubing hanger TH and running tool RT are assembled as shown in FIGS. 5A-5E with latching piston 128 extended by hydraulic fluid pressure in running tool latching chamber 134 which urges running tool latch ring 138 into engagement with latch groove 80 in tubing hanger TH. Hydraulic fluid pressure is then applied to control passage 92g, through check valve 62 and passage 60 to controlled landing chamber 58. This causes landing ring 40 and piston ring 42 to move downward until the inner edge of piston ring 42 is stopped by shoulder ring 30. Hydraulic fluid pressure is also applied to control passage 92d and hence tubing hanger unlocking chamber 132 which ensures actuator ring 70 is maintained in the unlocked position until the appropriate time. These operations place actuator ring 70 and landing ring 40 and piston ring 42 in the position shown in FIG. 2. The tubing hanger TH and running tool RT are then run into the wellhead W in a conventional manner until landing ring 40 contacts upper face 16 of casing hanger CH at which time the assembly is rotated until antirotation pin 20 engages antirotation slot 18. In this position, the metal-to-metal seal 34 is held up out of contact with casing hanger CH. The pressure in controlled landing chamber 58 is then released allowing the tubing hanger TH and running tool RT to descend to the position shown in FIG. 3 whereby camming ring 32 has engaged the tapered inner surface of landing ring 40 and activated metal-to-metal seal 34 into sealing engagement with casing hanger CH. Simultaneously, tubing hanger body 24 has moved downward allowing shoulder 14 to contact landing seat 12 of casing hanger CH and placing lock ring 64 adjacent locking recess 22.
Hydraulic fluid pressure is applied to control passage 92c and tubing hanger locking chamber 130 thereby urging torque piston 122 and actuator ring 70 downwardly to cam lock ring 64 into locking recess 22 as seen in FIG. 5E. As actuator ring 70 reaches its final locked position, its inner edge operates poppet valve 146 to direct the hydraulic fluid pressure in control passage 92c to passage 92h which is vented to the surface where, typically a pressure gauge is attached. An increase in hydraulic fluid pressure on this gauge provides a reliable indicator the tubing hanger is securely locked.
At this point if it is desired to release running tool RT from tubing hanger TH, hydraulic fluid pressure is applied to control passage 92f thereby urging latching piston 128 upwardly and releasing latch ring 138 from recess 80 allowing running tool RT to be retrieved to the surface. In this case a mechanical torque tool which has tabs on its lower end to engage torque slots 76 can be run on drillpipe and used to rotate torque ring 48 to its final preloaded position. If the running tool RT was left in place, hydraulic fluid pressure is then applied to control passage 92a to cause torque sleeve 102 to rotate and urge torque ring 48 to its final preloaded position in contact with locking ring 64 which is contacting locking recess 22. Running tool RT is then released from tubing hanger TH as previously described. Should it be desired to remove tubing hanger TH, running tool RT is rerun in a manner well known to those skilled in the art with orientation key 142 engaging slot 82 to ensure proper orientation upon reentry. The running tool RT can then be relatched to the tubing hanger TH and the tubing hanger TH unlocked from the wellhead housing 10 by pressurizing tubing hanger unlocking chamber 132 without the need to release or untorque the tubing hanger preload. | An improved subsea tubing hanger having a body with an external shoulder for landing on a seat within a subsea wellhead housing, locking ring carried on the hanger to engage an interior recess of the wellhead housing, with an actuator ring for setting the locking ring. A preloading mechanism includes an extendible ring cooperating with the locking ring to prevent any movement of the tubing hanger when engaged and operable by torque supplied by the running tool. The improved tubing hanger running tool includes a body secured to the tubing hanger by conventional latching ring with a rotatable outer sleeve having an interior helical groove. A piston positioned on the running tool body and operated by hydraulic fluid pressure has an exterior pin which coacts with the helical groove to provide torque to the actuating ring and preloading ring of the tubing hanger. | 4 |
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a spray gun usable with a module including a removable, easy-to-view, high-accuracy digital pressure gauge being installed in the spray gun as necessary.
2. Description of Related Art
The air spray gun uses compressed air to atomize a paint for spraying an object to be coated. To assure a stable quality of painting with the spray gun, it is necessary to always monitor and control the pressure of spraying compressed air. There are available some spray guns in which the spraying air pressure can be checked by the user operating the spray gun.
In the spray coating, both the quality of the finished coating and scattering of the paint mist greatly depend upon the spraying air pressure used in the air spray gun to spray paint on an object. Namely, it is well known that a higher air pressure will provide an increased energy for spraying and a finer atomization of the paint, which has generally contributed to an improved quality of paint coating. However, fine atomized mist of a paint is easily influenced by air flow to be more scattered. On this account, it is advisable to use a spray gun with an appropriate spraying pressure selected in accordance with the paint, object to be coated and coating conditions. For a quality spray coating, the spray gun should desirably be operated while monitoring the air pressure used for the spraying and under well-controlled conditions. In the recent spray guns, a lower air pressure is used to prevent the spray of paint from scattering, and thus because even a small change of the air pressure has a great influence on the coating quality, it has become more important to control the spraying air pressure.
Conventionally, the spraying air pressure is adjusted by a reducing valve or the like, and supplied through an air hose to the spray gun. During spraying of a paint, the user of the spray gun rarely checks the pressure of the air pressure. Recently, however, more and more air spray guns use a lower air pressure, and thus it has become important to adjust the air pressure within a lower pressure range and check the air pressure at hand.
Further, to assure a stable quality of painting and a quality skimming-coating of information devices and precision devices with a reduced amount of paint, it has become essential to appropriately control the paint spraying conditions.
Normally in the spray-coating tests, a spray gun is used with a pressure gauge being attached directly to the spray gun. In such tests, a general-purpose pressure gauge is connected to an air hose of the spray gun. However, the pressure gauge is rarely used in actual spray-coating because its weight and size are not acceptable in the routine paint spraying jobs.
It has been proposed to use a small pressure gauge installable directly to a spray gun and which permits the user of the spray gun to check the air pressure at any time in spraying a paint and will not interfere with the operation of the spray gun itself (cf. Japanese Published Examined Utility Model No. 22277 of 1993). This pressure gauge is an analog-indication one of a so-called Bourdon tube type. However, since the pressure gauge has to be designed smaller for installation to a spray gun which is normally not so large, such a pressure gauge is not satisfactory with respect to accuracy and durability in the operating environments.
Also, a spray gun with a digital-indication gauge using a pressure sensor is known from the disclosure in the Japanese Published Unexamined Utility Model No. 506310 of 1993. In this pressure gauge, a pressure gauge unit is housed in a closed container. When the service life of the driving cell has expired, the pressure gauge itself has to be discarded and replaced with a fresh one, which will lead to wasting of resources and addition of wastes.
The digital pressure gauge detects a pressure in an air channel and indicates it digitally, and this technology is already used in the general-purpose digital pressure gauge. The general-purpose digital pressure gauge includes a compressed air intake, pressure sensor, digital converter, indicator and a power unit, and it is used as an accessory to a spray gun. However, the pressure gauge thus used on the spray gun will add to the size and weight of the spray gun, which will cause increased fatigue of the user of the spray gun and will adversely affect the operability of the spray gun itself.
SUMMARY OF THE INVENTION
Accordingly, the present invention has an object to overcome the above-mentioned drawbacks of the related art by providing a spray gun usable with an accurate, easy-to-view pressure gauge which allows a spray coating of a stable and high quality, and can eliminate poor coating, minimize the paint consumption and prevent environmental pollution.
It is required that the pressure gauge used with the spray gun should be able to provide a stable pressure indication, have a long service life, be usable without any adverse influence on the shape and operability of the existent spray gun and permit the user to simply check an air pressure used in the spray gun.
The above-mentioned pressure gauge should preferably be an accurate, easy-to-view digital pressure gauge. However, this type of pressure gauge needs electric power, and thus it is important that a cell, which will be used as the power source, is replaceable taking account of the cell consumption.
Further, the cell should be safe enough so as not to cause any fire while spraying a paint diluted with a volatile solvent. Therefore, the cell should have an appropriate structure for use in a spray gun. Also it is a problem to solve by the present invention that to prevent a possible danger, the pressure gauge should easily be removable from the spray gun when no pressure indication is required for the spray gun.
Also, the spray gun once operated for spraying a paint has to be cleaned after use. Electronic parts used with the cell as the power source in the pressure gauge have to be protected against any affection caused by cleaning with a solvent. The above and other problems are solved by the present invention as will be described below.
According to the present invention, there is provided a spray gun including a spray gun body which atomizes a paint for spraying an object, and a pressure indication unit formed as at least a part of a grip of the spray gun to be removably installable on the spray gun grip and having assembled therein a pressure indication module including a pressure sensor, converter which is supplied with a detection signal from the pressure sensor and converts the signal into a digital signal, and a digital indicator to provide a digital indication of the digital signal output from the converter. Thus, an air intake can be provided independently of the spray gun body, and the pressure indication unit can be assembled to the spray gun body whenever necessary to accurately check a spraying air pressure on the spray gun body itself.
The pressure indication unit is formed integrally so as to form a pressure indication module, compressed air coupling and a portion for coupling to the spray gun body. Namely, the pressure indicator for indicating the pressure of compressed air introduced into the spray gun is designed as a unit. Thus, the pressure indication unit has an improved operability, can be produced separately from the spray gun body, can be assembled to the spray gun body as necessary to check the pressure of compressed air, and also can be used with another spray gun. That is, the pressure indication unit according to the present invention is highly versatile. More specifically, the pressure indication unit has the coupling portion at which it is installed on the spray gun body. Just attaching the pressure indication unit to the spray gun body will provide a spray gun which has a pressure indicator including the compressed air coupling connectable to a compressed air source.
The pressure indication module according to the present invention incorporates a digital converter which converts a pressure detection signal from a pressure sensor exposed in a compressed air channel into an electrical signal, and a pressure indicator which is supplied with the electrical signal output from the digital converter and digitally indicates the supplied electrical signal. Because of the integral forming of the main parts of the pressure indication module, the latter is designed sufficiently small to be incorporated in a pressure indication unit which will form a part of the spray gun grip. Thus the pressure indication unit can simply be attached to the spray gun which can thus permit the user to check the pressure of spraying air pressure easily and readily at hand.
Further, according to the present invention, there is provided a spray gun with a pressure indication module composed of a pressure sensor, digital converter and an indicator, formed integrally with each other. The pressure indication module has power terminals and a pressure-sensitive element of the pressure sensor exposed in the compressed air channel, the power terminals and pressure-sensitive element being exposed to the outside. Thus, the pressure indication module can easily be assembled to a device such as a spray gun and also assembled into the aforementioned pressure indication unit. It can maintain its stable performance and is connectable to a power source, which is provided separately.
Since the air gun is to spray a paint, and thus is always subject to adhesion of the paint, it is to be cleaned with a thinner and always exposed to an atmosphere of organic solvent. Also, the power unit and pressure indication module have to be airtight, especially at a portion where the electrical parts are provided, and therefore the electrical parts are isolated with a sealing material from outside.
Also, according to the present invention, there is provided an air spray gun in which compressed air having the pressure thereof adjusted is introduced through a compressed air intake and the atomizing air jet is controlled, the spray gun including a pressure sensor exposed in a channel for the adjusted compressed air and a pressure indication unit provided separately from the pressure sensor which receives a pressure detection signal output from the pressure sensor and converts the input pressure detection signal into an electrical signal. With this air spray gun, it is possible to check the pressure of compressed air accurately when the spray gun is being used, control the pressure of the compressed air that is spraying a paint to an object, and quickly adjust the compressed air pressure, if not appropriate, by an air pressure control valve provided in the spray gun to attain a stable quality of the paint spray coating.
Namely, the spray gun is normally supplied with compressed air having the pressure thereof adjusted at a compressed air source as having previously been described. Therefore, the spray gun can be used with compressed air whose pressure has been stabilized to some extent, but such a stability of the compressed air is not always sufficient when the user has to check and elaborately control the compressed air pressure. That is, even if the compressed air pressure is varied at the compressed air source, the user of the spray gun according to the present invention can readily check the pressure while spraying a paint and appropriately adjust the air pressure at the spray gun itself without leaving his or her spraying position.
Since the pressure sensor included in the present invention is provided in the air channel inside the spray gun to detect the actual pressure of an adjusted air jet, the pressure indication unit can always provide an accurate indication of the compressed air pressure in the course of spraying a paint and hence the user of the spray gun can operate the air pressure control valve in response to a variation in air pressure at the compressed air source. Namely, the user can instantly correct the pressure to a correct one and modify the spray gain to maintain a stable paint spraying operation.
Also, according to the present invention, an air pressure detection signal can be taken as an external signal, and supplied to a control unit provided separately to automatically control the pressure of compressed air.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing detailed description of the preferred embodiments of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view of the spray gun according an embodiment of the present invention.
FIGS. 2( a ) to 2 ( c ) show the construction of one embodiment of a pressure transducer used in the present invention, in which FIG. 2 ( a ) is a plan view of the pressure transducer, FIG. 2 ( b ) is a side elevation of the pressure transducer, and FIG. 2 ( c ) is a rear view of the pressure transducer.
FIG. 3 is a partial sectional view of the pressure transducer set in a pressure indication unit.
FIGS. 4( a ) to 4 ( c ) show the use of the spray gun according to the present invention, in which FIG. 4 ( a ) shows the grip of the spray gun to which the pressure indication unit according to the present invention is attached, FIG. 4 ( b ) shows the spray gun grip to which an adapter is attached, and FIG. 4 ( c ) shows the spray gun grip to which another adapter is attached.
FIG. 5 is an external view of an automatic spray gun according to another embodiment of the present invention, in which a pressure indication unit is provided.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , there is schematically illustrated in the form of a sectional view the spray gun according to an embodiment of the present invention. The spray gun is of a manual type operated by a trigger 1 . As shown, the spray gun includes a body and the spray gun body includes a gun barrel 6 having an atomization air cap 2 , paint supply adjuster 3 , spray pattern adjuster 4 and an air valve 5 , and a grip 7 extending backward and downward from the gun barrel 6 . A pressure indication unit 10 is removably fixed to the lower end of the grip 7 , and thus forms a part of the grip 7 .
The pressure indication unit 10 has a compressed air intake 11 formed at the lower end thereof. The compressed air intake 11 communicates with a central air channel 13 extending to a portion 12 for coupling to the spray gun body, formed at the upper end of the pressure indication unit 10 . The pressure indication unit 10 is externally threaded (indicated at a reference 14 ) on the outer surface thereof inside which the compressed air intake 11 is formed. An air hose is fitted on the threads 14 and compressed air is introduced into the pressure indication unit 10 from a compressed air source. The coupling portion 12 is formed from a projecting cylinder 16 having a gasket 15 fitted on the outer surface thereof. The coupling portion 12 is inserted into a coupling hole 8 formed in the spray gun body 1 and directs compressed air from the compressed air intake 11 to the air valve 5 .
The coupling portion 12 may be a projected portion of the spray gun body or simply a gasket, for example, which would be able to provide airtight channels in the coupling portion 12 and spray gun body 1 . The pressure indication unit 10 is fixed with a screw 9 to the grip 7 after connecting the coupling unit 12 to the spray gun body 1 in an airtight manner. This fixation may of course be done otherwise.
The pressure indication unit 10 has built therein a pressure transducer 24 which is applied with the pressure of compressed air introduced through a branch channel 28 communicating with an air path 13 between the compressed air intake 11 and coupling portion 12 . The pressure transducer 24 is illustrated in detail in FIG. 2 . It is assembled in the pressure indication unit 10 as shown in FIG. 3 . As will be apparent, the pressure transducer 24 includes a pressure sensor 25 having a part thereof exposed to the branch channel 28 , a digital converter circuit board 26 which converts a displacement of the pressure sensor 25 into an electrical signal, and an indicator 27 . These components of the pressure transducer 24 are formed integrally with each other.
The pressure transducer 24 includes an operation power unit 18 . The power unit 18 has a button-shaped cell removably housed in a cell compartment. The power unit 18 is connected to power terminals 18 A and 18 B of the pressure transducer 24 . The power unit 18 and indicator module are separately settable and removable. Thus, only the cell is a consumable part, and the cell can easily be replaced.
The pressure transducer 24 in which its elements are formed integrally with each other is fitted in a concavity formed in a part of the pressure indication unit 10 as shown in FIG. 3 . A cover 23 is provided over the pressure transducer 24 with a gasket 19 placed under the cover 23 . Thus the pressure transducer 24 is kept airtight. However, the pressure transducer 24 may be otherwise kept airtight correspondingly to its shape. Also, the power terminals 18 A and 18 B may be provided in places where they are connected directly to the cell. Although the places depend upon the location of the cell, the power terminals 18 A and 18 B may be connected indirectly to the cell each with each cord or connection piece.
A part of the pressure sensor 25 is exposed in the branch channel 28 communicating with the compressed air channel 13 to detect the pressure of supplied compressed air. The digital converter, formed as the circuit board 26 , is electrically connected in a predetermined relative position to the indicator 27 formed from a liquid crystal panel. The pressure sensor 25 , circuit board 26 and indicator 27 are desirably molded from an insulative resin as a pressure indication module held airtight while the power terminals 18 A and 18 B and a pressure-sensitive element 25 A of the pressure sensor 25 are exposed to outside. Since the pressure indication module has thus an integrated structure as a small digital pressure gauge, it can provide a stable pressure indication and it is usable in any other device which requires a pressure indication, such as a hand-held device whose mass and size are limited.
The pressure transducer 24 converts a strain the pressure sensor 25 incurs when applied with a pressure into an electrical signal and displays the electrical signal as a digital indication signal on the indicator 27 . It adopts the conventional digital conversion technology.
The pressure indication unit 10 is designed with consideration given to its appearance which should desirably fit the grip 7 . When attached to the spray gun, it forms a part or all of the grip and thus adds a pressure indication function to the spray gun without spoiling the easy operability of the spray gun.
FIG. 4 ( b ) shows a combination of the spray gun with an adapter 21 having the same appearance as the pressure indication unit 10 and provided with a compressed air intake and coupling portion. The adapter 21 is to be attached to the spray gun grip. FIG. 4 ( a ) shows a combination of the spray gun with the pressure indication unit 10 used in combination with the spray gun and shaped to fit the grip.
FIG. 4 ( c ) shows another adapter 22 incorporating an air supply adjusting means, which will permit a functional expansion of the spray gun.
With these adapters, the spray gun according to the present invention can be used as an ordinary one without any pressure indication. In case the paint spraying conditions are not so strict and the user of the spray gun can feel a change of air pressure and adjust the pressure, the spray gun may be used with any of these adapters. However, in case even a slight change in air pressure will adversely affect the finish of the painting, a paint should be sprayed under an ample pressure control or the air pressure has to be checked during spraying because the user cannot himself or herself judge the air pressure, the spray gun can be used with the pressure indication unit, which can be readily and easily replaced with any of the adapters.
Since the pressure indication unit incorporating electrical and electronic parts can be separated from other parts, the spray gun itself can advantageously be cleaned by washing in a thinner without any problem.
FIG. 5 shows an application of the present invention to an automatic spray gun in which paint spraying can automatically be controlled with an external signal. The automatic spray gun is supplied with compressed air under a pre-adjusted pressure. In the conventional automatic spray gun, however, the controller and spray gun are apart from each other and the pressure under which a desirable condition of spraying is maintained will vary depending upon the condition of the air-supply hose and operating conditions. Therefore the aforementioned problems cannot be solved by the conventional automatic spray gun. FIG. 5 shows another application of the pressure indication unit to such an automatic spray gun. It should be noted that the present invention is not limited to an automatic spray gun having any special structure.
As having been described in the foregoing, the present invention provides the pressure indication unit which accurately detects and indicates a spraying air pressure as an important factor in using the spray gun and can be installed easily and readily to the spray gun when necessary. The pressure indication unit allows the user of the spray gun to easily check and control the spraying air pressure. This effect of the pressure indication unit according to the present invention can be applied to the ordinary spray gun as well as the automatic spray gun.
Namely, since the pressure indication unit is designed as a removable module having necessary functions integrated therein, it can be attached to the spray gun when necessary to check and control the spraying air pressure. When no pressure indication is required, any of the adapters having no such function may be installed in place of the pressure indication unit, which will lead to saving of any extra costs and to a reasonable use of the spray gun.
Also, the pressure indication unit according to the present invention is designed to form a part of the grip of the manual spray gun, and it adds no excessive part to the spray gun. It allows the user of the spray gun to always check the spraying air pressure and thus prevent any defect in a painted surface or nonuniform coating due to any unexpected pressure change.
More specifically, the pressure indication unit according to the present invention is superior in accuracy, reliability and durability to the conventional analog pressure gauge. It assures an accurate checking of a spraying air pressure which has been just a measure of the painting quality, and permits a user to apply a spray coating under a relatively low pressure and strictly control spraying conditions for a quality paint coating.
The present invention provides a spray gun to which a module including an easy-to-view, accurate digital pressure gauge can be assembled. The accuracy and easy viewing of the pressure gauge assure a stable spraying operation for a quality coating, which will result in the elimination of poor coating, reduction of paint consumption and prevention of environmental pollution. | A spray gun with pressure display for applying paint onto a painted object by atomizing the paint with compressed air. A pressure indicating device includes a digitally displayed pressure sensor ( 25 ), a pressure transducer part ( 24 ), and a display part ( 27 ) unitized with each other. The pressure indicating device is detachably installed on a spray gun body, and adapters ( 21, 22 ) without a pressure indication function are detachably fitted to the spray gun body according to the shape of the body grip part so that the presence or absence of the pressure indication function can be selected before use. The spray gun can be used under controlled conditions by allowing a worker to detect an air pressure at hand during spraying operation since the spraying air pressure largely affects paint finish as well as dispersion of atomized paint. | 1 |
FIELD OF THE INVENTION
This invention relates to manual shovels having shock absorbing handles for manipulating the blades to load and unload debris.
BACKGROUND OF THE INVENTION
The shovel may be one of the oldest known hand tools. The basic components are an elongated handle which serves as a lever to increase force on the blade. The handle is connected to a blade comprising a solid load bearing plate terminating in a straight or curved edge. The handle is used to swing or rapidly push the blade into debris and any obstruction encountered by the blade is transmitted through the handle to the hands and arms of the user. The handle is usually made of wood and the blade is of metal. Some blades are flat, some are simple curves and some are compound curves for scooping material.
The handle may be a straight or curved shaft with one end connected to the blade in numerous ways, such as rivets, nails, bolts, etc. Other handles may have a “D-shape” terminal end opposite the blade with a cross bar perpendicular to the long shaft of the handle providing greater thrust to the blade.
DESCRIPTION OF THE PRIOR ART
There are many variants of shock absorbing handles designed to lessen the shock and resultant strain on the user. For example, publications, such as WO 9952685A1 and WO 9739858A1 disclose snow shovels with two piece telescoping handles having an internal spring and guide to limit travel and prevent rotation. Also, U.S. Pat. No. 5,533,768; U.S. Pat. No. 4,691,954; and U.S. Pat. No. 6,792,829 each disclose a shovel handle with two components separated by a spring or resistence mechanism to reduce the shock forces. In each of the disclosed devices, the resilient portion of the handle is located approximately where the user may grip the shaft.
In the '768 patent the handle shaft, per se, has an integral flexible portion that distorts to lessen shock.
In the '954 patent, the shovel handle has an upper and a lower portion that telescope together compressing an internal spring to lessen shock.
In the '829 patent, the lower portion of the handle has a smaller diameter extension that telescopes throughout the upper portion terminating near the “D-shaped” grip. The upper portion of the handle terminates in a shoulder that engages a coil spring disposed about the smaller diameter extension.
SUMMARY OF THE INVENTION
What is needed in the art is a lightweight molded shovel with a large scoop blade and a compact shock absorbing mechanism located in the handle at a point so as not to interfere with the operation of the shovel.
Disclosed is a lightweight molded plastic shovel for removing snow and ice has a reinforced scoop and a shock absorbing mechanism in the handle. The handle has a “D shaped” hand grip at one end telescoped over a guide surrounded by a coil spring. The other end of the guide telescopes into the shaft of the handle. The movement of the “D shaped” hand grip toward the scoop compresses the spring reducing shock during use.
Accordingly, it is an objective of the instant invention to provide a molded plastic shovel with a shock absorbing handle for moving snow and other particulate material from one place to another.
It is a further objective of the instant invention to provide a compound curved blade with reinforcing ribs and an integral socket for connection to a plastic coated steel handle.
It is another objective of the instant invention to provide a shock absorbing mechanism having a center guide extending through upper and lower brackets and surrounded by a coil spring with the opposite ends of the spring contacting each bracket, respectively.
It is yet another objective of the instant invention to provide a shock absorbing shovel handle having a guard over the shock absorbing portion of the handle to prevent pinching.
It is a still further objective of the invention to provide a molded plastic “D shaped” end on the handle opposite the blade.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. Any drawings contained herein constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective of the assembled shovel of this invention; and
FIG. 2 is an exploded view of the shovel of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
The shovel 10 , shown in FIG. 1 , has an elongated handle 11 with a “D shaped” hand grip 12 on one end and a blade 13 on the other end. The blade 13 has a straight edge 14 for separating the shovel load from the mass of material to be moved. The hand grip and blade components are made of molded plastic polymers having the necessary strength and rigidity to repeatedly separate and lift a scoop full of material, such as snow and ice. The elongated handle is constructed of a suitable metal, such as steel, and coated with a suitable polymer, such as plastic, to prevent surface deterioration and/or oxidation of the handle.
The blade 13 is curved in the longitudinal and lateral axes to form a deep scoop. The deep reinforcing ribs 15 add strength to the blade and also function to divide the load into segments for easy separation from the blade during unloading. In addition to the ribs 15 , the blade has a socket 16 into which one end of the handle 11 is inserted. The socket 16 forms a partition 17 extending through the center of the blade 13 . Stabilizing flange 18 and stabilizing flange 19 project from the longitudinal sides of the socket 16 providing additional resistence against torque on the blade from uneven loads. The blade 13 is a one piece molded component preferably constructed through the process of injection molding.
The bottom of the handle 11 is inserted into the socket 16 to a depth approximating the center of the blade adding more strength to the blade and ensuring adequate overlap to the connection. The handle and socket may be secured through the overlap by rivets, bolts, adhesive, or thermoplastic welding (not shown). The plastic coated steel handle extends from the blade to the “D shaped” end of the handle providing a smooth stable lever for manipulation by the user. The handle 11 may alternatively be constructed from aluminum or fibreglass with a suitable bore to receive guide 23 .
The one piece molded “D shaped” end 12 has yoke 32 supporting the opposite ends of a hand grip 31 oriented perpendicular to the longitudinal axis of the handle. The yoke 32 has a stem 33 extending along the longitudinal axis of the handle. The stem has a rivet hole 34 , as shown in FIG. 2 , for connection with the shock absorbing mechanism 20 . Other fastening devices may be used, as mentioned above.
The shock absorbing mechanism 20 is composed of an upper bracket 21 and a lower bracket 22 . The upper bracket is attached to the stem 33 of the “D shaped” handle, either directly or by the connector 30 . The connector 30 provides reinforcement, particularly when the connection is by a rivet or through bolt 26 extending through the bracket, the connector and the stem. The upper bracket 21 is formed as an annular plate having an attached or integrally formed guard 37 . The guard 37 is constructed and arranged to extend around the coil spring 24 to prevent pinching during operation of the shock absorbing mechanism. The guard is preferably constructed of a transparent plastic material, but may alternatively be constructed from opaque materials suitable for guarding the shock absorbing mechanism. The lower bracket 22 is formed as an annular plate with a central bore. Extending normal to the annular portions of the upper and lower brackets about the circumferences thereof are a pair of upper ears 35 and lower ears 36 . The stem 33 and the connector 30 extend between the ears 35 and engage the annular plate. A rivet 26 or other fastener penetrates the upper ears, the connector 30 and the stem 33 to secure the “D shaped” hand grip to the shock absorbing mechanism.
The upper end of the handle 11 attaches to lower bracket 22 by extending between the lower ears 36 to contact the annular plate of the bracket. As shown, a rivet 25 extends through the ears 36 and the handle fastening the handle to the shock absorbing mechanism 20 . The end of the handle has a bore into which the guide 23 slides. The bore extends at least the length of the slot 35 .
The guide 23 is of a size to telescope through the central bores of the annular plates of the upper and lower brackets. The guide has a slot 35 through which the rivet 25 extends. The slot 35 limits the travel of the shock absorbing mechanism 20 . The guide 23 is surrounded by a biasing member illustrated herein as coil spring 24 which is compressed between the annular plates of the upper and lower brackets when the “D shaped” hand grip moves toward the blade. The compression of the spring cushions the shock produced by encountering obstructions with the blade.
All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein-incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein.
One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | A lightweight molded plastic shovel for removing snow and ice has a reinforced scoop and a shock absorbing mechanism in the handle. The handle has a “D shaped” hand grip at one end telescoped over a guide surrounded by a coil spring. The other end of the guide telescopes into the shaft of the handle. The movement of the “D shaped” hand grip toward the scoop compresses the spring reducing shock during use. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. provisional application No. 60/123,176, filed Mar. 5, 1999, hereby incorporated herein by reference, entitled “Integrating Fluxgate Magnetometer and Spatially Integrating Magnetometer.”
This application is related to U.S. nonprovisional application Ser. No. 09/262,932, filed Mar. 5, 1999, now U.S. Pat. No. 6,344,743 B1, hereby incorporated herein by reference, entitled “Standing Wave Magnetometer,” joint inventors John J. Holmes and John F. Scarzello.
This application is related to U.S. nonprovisional application Ser. No. 09/517,560, filed Mar. 2, 2000, hereby incorporated herein by reference, entitled “Spatially Integrating Fluxgate Magnetometer Having a Flexible Magnetic Core,” joint inventors John F. Scarzello, John J. Holmes and Edward C. O'Keefe.
This application is related to U.S. nonprovisional application Ser. No. 09/517,558, filed Mar. 2, 2000, now U.S. Pat. No. 6,278,272 B1, hereby incorporated herein by reference, entitled “Integrating Fluxgate Magnetometer,” joint inventors John F. Scarzello, John J. Holmes and Edward C. O'Keefe.
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
The present inventions relate to methods, systems and apparatuses for performing measurement pertaining to magnetic field, more particularly to such methods, systems and apparatuses for measuring a magnetic field at the surface of a ferromagnetic material.
Ships and submarines are constructed of ferromagnetic materials which produce magnetic field signatures, making them detectable and vulnerable to magnetic influence sea mines and detectable by airborne magnetic anomaly detection (MAD) and underwater electromagnetic surveillance systems.
To reduce the magnetic field signature of ships and submarines, coils are wrapped around the ferromagnetic hull, and fields produced which reduce the vessel's signature. In order to control the coil currents, a degaussing (DG) system must have sensors which accurately measure the signature-related magnetic fields, and control algorithms to extrapolate the spatially measured field values to regions under the ship, and adjust the coil currents to minimize the signature amplitude.
It is useful to measure magnetic fields near the hull of naval ships and submarines, so that such measured magnetic fields can be used to control advanced degaussing systems. A large number of “point” sensors are presently employed, but they are expensive and not capable of satisfying the need for measuring fields at all points along the circumference of a ship or submarine hull. It is important to measure these fields produced by local hull anomalies (welds, stresses, bulkheads, etc.) and material inhomogeneities at many locations, for more effective control of the ship's degaussing system. Ideally, by measuring the surface magnetic fields all over the hull (and thereby continuously monitoring the magnetic state of a ship or submarine hull), the magnetic field signature of the ship can be adjusted and maintained at a low level using an advanced degaussing system such as the U.S. Navy's Advanced Closed Loop Degaussing System, thereby maldng a ship less vulnerable to sea mine magnetic influence fuzes.
Advanced degaussing systems require accurate and spatially distributed magnetic field measurements around the ship, so that ship mathematical model algorithms can precisely control magnetic field signatures below the ship. Some of the problems associated with measuring these fields include: large spatial gradient magnetic fields; local magnetic anomalies; induced magnetic fields caused by heading changes; and, permanent magnetization changes due to pressure-induced hull stresses. Such measurements have been made using traditional fluxgate magnetometers, short baseline gradiometers, etc.
In some cases, there are large spatial magnetic field gradients, close to the hull, which are produced by local hull anomalies (e.g., welds, stresses, bulkheads, etc.) and material inhomogeneities. “Point” triaxial fluxgate magnetometers and gradiometers are presently used to measure these spatial gradients; however, because of these local effects, field measurements at many locations may not be useful for controlling the shipboard degaussing system.
Fluxgate magnetometers measure the magnetic field intensity using a variety of transducer cores which, normally, are considered to be small “point” field sensors (typically, about one to two inches in length). More generally, fluxgate, fiber-optic and other magnetic field sensitive transducer phenomena measure the magnetic field intensity using a variety of transducer cores which are normally considered point field measurements (wherein the transducers are typically about one to two inches in length).
A ship or submarine with a ferromagnetic hull produces a magnetic field signature which is dependent on the hull material magnetic characteristics, it's geometry in the earth's magnetic field, and stresses which are applied to the hull. Present degaussing systems sense the magnetic fields relatively close to the hull, and adjust the degaussing coil currents to minimize the fields at a distance below the vessel which can be sensed by magnetic influence sea mines. The ferromagnetic hull material's characteristics are used in complex ship models which are able to predict a vessels magnetic field signature below the ship. However, the characteristics may change significantly with respect to stress, heading, and time.
Ferromagnetic material sample characteristics are presently measured using ASTM “Standard Methods of Testing Magnetic Materials, which include DC fluxmeter, and alternating current techniques; see ASM Standard Methods of Testing Magnetic Materials, A34-70, American National Standards Institute, Part 8, incorporated herein by reference. Other techniques include balance permeameters for feebly magnetic materials, and portable permeameters, sometimes used as “magnaflux probe” for non-destructive testing of structural materials; see Sery, R. S., Permeameter Development and Use for Measuring Magnetic Permeability of SSN and High Strength Steels, NSWC TR 80-347, Oct. 1, 1980, Naval Surface Weapons Center, White Oak, Md., incorporated herein by reference.
Other pertinent background information is provided by the following papers, each of which is hereby incorporated herein by reference: Lenz, J. E., “A Review of Magnetic Sensors,” IEEE Proceedings, Vol. 78, No. 6, June 1990;Gordon, D. I., R. E. Brown and J. F. Haben, “Methods for Measuring the Magnetic Field,” IEEE Trans. Mag., Vol. Mag-8, No. 1, March 1972; Gordon, D. I. and R. E. Brown, “Recent Advances in Fluxgate Magnetometry,” IEEE Trans. Mag., Vol. Mag-8, No. 1, March 1972; Gordon, D. I., R. H. Lundsten, R. A. Chiarodo, H. H. Helms, “A Fluxgate Sensor of High Stability for Low Field Magnetometry,” IEEE Transactions on Magnetics, vol. MAG-4, 1968, pp 379-401; Acuna, M. H., “Fluxgate Magnetometers for Outer Planets Exploration,” IEEE Transactions on Magnetics, vol. MAG-10, 1974, pp 519-23.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide method, apparatus and system for measuring magnetic characteristics of a ferromagnetic material such as that of a ship's hull.
It is another object of the present invention to provide method, apparatus and system for continuously measuring same, for use in association with a magnetic control system such as a ship degaussing system.
All magnetic materials can be characterized by a hysteresis curve, which is a two dimensional plot of Induction (B in weber/m 2 =10 4 gauss) versus Magnetic Field intensity (H in ampere/meter=0.01256 Oersted). The ratio of B/H is defined as the magnetic permeability of the material (weber/m-amp=henry/meter=newton/amp 2 or 1 hy/m=79.6×10 3 gauss/oersted), and varies non-linearly with respect to field amplitude, and mechanical stress.
At the surface of a ship or submarine hull or any ferromagnetic material, the normal component of the Induction (B) and the transverse component of Field Intensity (H) are each continuous across the surface boundary. The fields at the surface are dependent on the bulk material magnetic properties (permeability), which are dependent on the ambient magnetic field, the stress on the material which changes the characteristics of the magnetic material, and other local effects.
The “Ferromagnetic Surface Magnetic Field Sensor” (“FSMFS”) in accordance with the present invention features measurement of magnetic field at the surface of a ferromagnetic material (e.g., at the surface of a ship's hull) by measuring either or both the transverse H field and the normal B (Induction), using the ferromagnetic properties of the material as part of the sensor transducer. This invention advantageously senses magnetic characteristics of ferromagnetic material while obviating the need to alter such material.
The present invention provides a fluxgate device for sensing the transverse component of the magnetic field intensity H at a surface area of a ferromagnetic entity. The inventive device comprises a magnetic core, a drive winding and two sense windings. The magnetic core generally describes a three-dimensional “E” shape. The magnetic core including four portions. The four portions are a base portion and three leg portions each projecting from the base portion. The three leg portions are a first end leg portion, a second end leg portion and a middle leg portion. The middle leg portion is approximately equidistantly interposed between the first end leg portion and the second end leg portion. The first end leg portion, the second end leg portion and the middle leg portion each have a leg end surface for being situated adjacent the surface area of the ferromagnetic entity when the device is positioned with respect to the ferromagnetic entity. The drive winding is wound over the middle leg portion. The two sense windings are a first sense winding and a second sense winding. The first sense winding is wound over the base portion between the first end leg portion and the middle leg portion. The second sense winding is wound over the base portion between the second end leg portion and the middle leg portion. Typically, the device further comprises three calibration windings. The three calibration windings are a first calibraton winding, a second calibration winding and a third calibration winding. The first calibration winding is wound over the first end leg portion. The second calibration winding is wound over the middle leg portion. The third calibration winding is wound over the second end leg portion.
The present invention also provides a fluxgate device for sensing the normal component of the magnetic induction B at a surface area of a ferromagnetic entity. The device comprises a magnetic core, a drive winding and a sense winding. The magnetic core generally describes a semi-open coaxial double-cylinder shape. The magnetic core includes an approximately cylindrical bucket-shaped portion and an approximately cylindrical solid portion. The approximately cylindrical solid portion has a smaller diameter than has the approximately cylindrical bucket-shaped portion. The approximately cylindrical bucket-shaped portion has an annular end surface. The approximately cylindrical solid portion has a continuous circular end surface. The annular end surface and the continuous circular end surface are for being situated adjacent the surface area of the ferromagnetic entity when the device is positioned with respect to the ferromagnetic entity. The drive winding is wound over the approximately cylindrical solid portion. The sense winding is wound over the approximately cylindrical solid portion. Typically, the device further comprises a calibration winding which is wound over the approximately cylindrical solid portion.
The purpose of the present invention, in the context of the U.S. Navy's effort, is to continuously measure magnetic characteristics of the material of a ship's hull at many locations, and to supply the measured data to the ship degaussing system's model-based control algorithms. The present invention's U.S. Navy prototype FSMFS is designed to measure a ferromagnetic hull's magnetic characteristics continuously. According to inventive principles, the B and H values of the surface properties of the hull can be determined by using the hull material itself as part of the transducer element. The inventive methodology dynamically measures, in real time, any change in hull magnetic characteristics including permanent magnetism, as well as induced magnetism and magnetization produced by hull stress.
Thus provided by the present invention is a type of ferromagnetic material (e.g., hull material) “permeameter.” The invention's FSMFS can use either crystalline or amorphous magnetic materials in the transducer core. The U.S. Navy's prototype FSMFS sensor uses modified electronics which the U.S. Navy developed for its prototype IFM sensor.
Related to (but distinguishable from) the inventive FSMFS is the inventive “Integrating Fluxgate Magnetometer” (IFM) which is disclosed by the aforementioned U.S. Pat. No. 6,278,272 B1. A typical inventive Integrating Fluxgate Magnetometer (IFM) is a fluxgate magnetometer having a rigid transducer core which is configured as a long “race track” in order to integrate large component gradient magnetic fields near a ferromagnetic entity, e.g., a ship hull or a large piece of machinery. A typical inventive IFM: (i) measures magnetic fields over the length of its elongated transducer element (e.g., the 30 cm length of an inventive prototype tested by the U.S. Navy), and (ii) spatially integrates the component field amplitudes.
Also related to (but distinguishable from) the inventive FSMFS is the inventive “Spatially Integrating Magnetometer” (SIM) which is disclosed by the aforementioned U.S. nonprovisional patent application Ser. No. 09/517,560. A typical Spatially Integrating Magnetometer (SIM) measures the magnetic field at discrete distributed points, or summation of all field components, along a “linear,” flexible transducer element. According to many inventive SIM embodiments, a spatially integrating transducer magnetometer measures the magnetic field components (tangential and normal) over a very long linear region, at discrete points, and integrates component field values (the sum of the field component amplitudes) over the length of the spatially integrating tranducer magnetometer's sensor element. A typical inventive SIM: (i) measures magnetic field amplitude components over a very long linear region, at discrete points, and (ii) integrates these component field values (the sum of the field component amplitudes) over the length of the transducer element.
Also related to (but distinguishable from) the inventive FSMFS is the inventive “Standing Wave Magnetometer” (SWM) which is disclosed by the aforementioned U.S. Pat. No. 6,344,743 B1. In accordance with many embodiments of the inventive SWM, a methodology is provided for determining the distribution of a magnetic field in a spatial sector. According to a typical inventive SWM, a magnetic field amplitude value is measured at each of a plurality of points in the sector, wherein the means for measuring is characterized by a length which is defined by the points. Alternating current is applied at a high frequency having an associated wavelength which corresponds to a multiple of the length. The applied alternating current is conducted so as to establish a standing wave along the length. The measured magnetic field amplitude values are processed; this processing includes performing, over the multiple of the length, Fourier analysis based on a harmonic bias function which results from the standing wave.
Other objects, advantages and features of this invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE APPENDICES
Incorporated herein by reference is the following technical report: Scarzello, John F. and Edward C. O'Keefe, “Development of Shipboard Magnetic Sensors for Degaussing System Controllers,” NSWCCD-TR-98/011, Jun. 30, 1998, Machinery Research and Development Directorate Research and Development Report, Naval Surface Warfare Center, Carderock Division, West Bethesda, Md. 20817-5700. See, especially, Chapter 6 of this report. This report includes 93 pages, including 43 pages of drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the present invention may be clearly understood, it will now be described, by way of example, with reference to the accompanying drawings, wherein like numbers indicate the same or similar components, and wherein:
FIG. 1 is a diagrammatic representation of a ferromagnetic material, illustrating the Induction (B) and Field Intensity (H) components of the ferromagnetic material.
FIG. 2 is a diagrammatic representation of a ship's hull which is made of a ferromagnetic material, illustrating, similarly as does FIG. 1, the Induction (B) and Field Intensity (H) components of the hull.
FIG. 3 is an exemplary graphical representation of magnetic induction as a function of applied magnetic field strength for positive transverse stress (tension) ranging from 0 to 400 Mpa. The stress results in an effective demagnetizing field which shears the hysteresis loop.
FIG. 4 is a graphical representation, related to FIG. 3, of the normal magnetic induction component as a function of stress.
FIG. 5 is a diagrammatic perspective view, juxtaposed on a ferramagnetic surface such as a ship's hull surface, of the U.S. Navy prototype magnetic induction “Ferromagnetic Surface Magnetic Field Sensor” (“FSMFS”) and the U.S. Navy prototype magnetic field intensity “Ferromagnetic Surface Magnetic eld Sensor” (“FSMFS”), in accordance with the present invention.
FIG. 6 is a diagrammatic perspective view of the “E” core of the inventive prototype magnetic field intensity H FSMFS shown situated on a ferromagnetic (e.g, hull) surface in FIG. 5 .
FIG. 7 is a diagrammatic circuit and cutaway elevation view of the “E” core for the inventive prototype magnetic field intensity H (“E” core) FSMFS shown situated on a ferromagnetic (e.g, hull) surface in FIG. 5 .
FIG. 8 is a diagrammatic perspective view of the “Pot” core of the inventive prototype magnetic induction B FSMFS shown situated on a ferromagnetic (e.g, hull) surface in FIG. 5 .
FIG. 9 is a diagrammatic circuit and cutaway elevation view of the inventive prototype magnetic induction B (“Pot” core) FSMFS shown situated on a ferromagnetic (e.g., hull) surface in FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 and FIG. 2, a basis for the present invention is the existence of physical boundary conditions between a magnetic material 10 and a non-permeable medium (such as air 12 ), specifically the physical boundary conditions as pertains to the physical phenomena of magnetic induction (alternatively called magnetic flux density) B and magnetic field intensity (alternatively called magnetic field strength) H. At the surface 11 of a ship or submarine hull or any other ferromagnetic material 10 , the normal component of the magnetic induction B and the transverse component of the magnetic field intensity R are each continuous across the surface 11 boundary.
As shown in FIG. 1 and FIG. 2, the induction B normal component is continuous across the boundary defined by first (upper, as shown) surface 11 a and is continuous across the boundary defined by second (lower, as shown) surface 11 b. Also as shown in FIG. 1 and FIG. 2, the field intensity h transverse component is continuous across the boundary defined by first (upper, as shown) surface 11 a and is continuous across the boundary defined by second (lower, as shown) surface 11 b.
Magnetic permeability is the measure of the ability of a material to modify a magnetic field, and is equal to the ratio of the magnetic induction B to the magnetic field intensity H. The magnetic fields at the surfaces 11 a and 11 b are dependent on the magnetic properties (magnetic permeability) of the bulk material 11 . These magnetic properties are dependent on the ambient magnetic field, the stress on the material which changes the characteristics of the magnetic material, and other local effects. In particular, magnetic induction B and magnetic field intensity H in hull material 10 are a function of the ambient field, the degaussing coil fields, geometry, stress and temperature.
For instance, with reference to FIG. 3, a ferromagnetic material's hysteresis curve is subject to various levels of pressure-induced stress, resulting in an effective demagnetization field which shears or degrades the hysteresis loop. With reference to FIG. 4, the normal B field component can be measured with respect to stress.
Reference now being made to FIG. 5, the ferromagnetic surface magnetic field sensor in accordance with this invention typically comprises the combination of two inventive kinds of ferromagnetic surface magnetic field sensors, viz., (i) the normal B field (magnetic induction) component sensor 30 and (ii) the transverse H field (magnetic field intensity) component sensor 40 . It is emphasized that, in accordance with the present invention, either the B field component or the H field component can be measured in the absence of the other; however, many embodiments preferably implement both kinds of inventive transducers, in order to obtain a more complete assessment of the magnetic condition of the ferromagnetic material in question.
The U.S. Navy is interested in the present invention for utilization in relation to marine vessels. For many such applications, the inventive ferromagnetic surface magnetic field sensor can be aptly termed a “hull surface magnetic field sensor.” The objective of the present invention's hull surface magnetic field sensor is to measure the hull's surface B and H parameters so that it may be possible to more fully determine the magnetic condition of the ship's hull. FIG. 1 and FIG. 2 illustrate the B and H components which can be inventively measured with surface sensors either inside or outside the hull, or both inside and outside the hull. If, for instance, both B and H surface fields are measured around the outside of the hull 10 , advanced degaussing controller algorithms and degaussing coils can reduce signatures sufficiently to provide protection against magnetic influence sea mines and surveillance systems.
Fluxgate magnetometers have been developed to measure magnetic fields since the late 1930's. They use a ferromagnetic material as the transducer element, which is cyclically driven into saturation, which controls the flux in the core. To measure the controlled flux driven core plus that provided by the external or ambient magnetic field, the field dependent induced second harmonic signal of the saturated core is measured and compared to the second harmonic of the drive signal, whose amplitude is proportional to the ambient field intensity, with phase corresponding to field polarity.
The hull material transducer according to this invention utilizes a fluxgate magnetometer principle, but applies the principle to a transducer core that employs the hull material as part of the transducer element. In other words, according to this invention, the ferromagnetic material of the hull becomes part of the ferromagnetic material of the transducer circuit. By incorporating the ferromagnetic hull material, which has a different magnetic hysteresis curve than the well-defined transducer core, the boundary magnetic fields can be measured.
As illustrated in FIG. 5 through FIG. 9, an “E” core and a “Pot” core are used as the transducer elements for measurement of the H T (the transverse H field) component and the B N (the normal B field) component, respectively. Normal B field component sensor 30 includes magnetic Pot core 31 . Transverse H field component sensor 40 includes magnetic E core 41 .
Still referring to FIG. 5 and also referring to FIG. 6 and FIG. 7, the U.S. Navy's inventive prototype transverse H field component sensor 40 has a tangential H field measurement core design comprising magnetic material and characterized by an “E”-shaped geometry. Transverse H field component sensor 40 resembles in shape the letter “E”—the upper case form of the fifth letter of the English language alphabet.
Although E core 41 of transverse H field component sensor 40 is a unitary member, for geometrically descriptive purposes E core 41 can be considered to be regionalized so as to have a base 42 section and (demarcated with respect thereto via intersecting plane h, indicated with dashed line) three approximately parallel “leg” 43 sections which are each approximately perpendicular to base 42 and are approximately parallel to each other. Base 42 is shown to be approximately horizontal, and is approximately vertical when the letter “E” is upright. Legs 43 are shown to be approximately vertical, and are approximately horizontal when the letter “E” is upright.
The three legs 43 can be designatively differentiated among themselves as middle leg 43 m and two end legs 43 e 1 and 43 e 2 . The three legs 43 m, 43 e 1 and 43 e 2 are each approximately vertical and approximately perpendicular to base 42 , and are approximately perpendicular to ferromagnetic surface 11 when transverse H field component sensor 40 is appropriately situated.
E core 41 has a rectilinear configuration formed by approximately flat (planar) surfaces sharing approximately straight (linear) edges with adjacent surfaces and oriented approximately orthogonally with respect to the adjacent surfaces. Base 42 and legs 43 m, 43 e 1 and 43 e 2 each approximately describe a rectangular parallelepiped. Legs 43 m, 43 e 1 and 43 e 2 are approximately congruent rectangular parallelepipeds. Leg 43 m is approximately equidistant between leg 43 e 1 and leg 43 e 2 .
Legs 43 m, 43 e 1 and 43 e 2 each have four exposed side surfaces and, perpendicular thereto, an exposed end bottom or lower) surface. Leg 43 m has two approximately parallel lengthwise side surfaces 44 m and 44 m ′ and, approximately perpendicular thereto, two approximately parallel widthwise side surfaces 45 m and 45 m ′ and a bottom surface 46 m. Leg 43 e 1 has two approximately parallel lengthwise side surfaces 44 e 1 and 44 e 1 ′ and, approximately perpendicular thereto, two approximately parallel widthwise side surfaces 45 e 1 and 45 e 1 ′ and an end (bottom) surface 46 e 1 . Leg 44 e 2 has two approximately parallel lengthwise side surfaces 44 e 2 and 44 e 2 ′ and, approximately perpendicular thereto, two approximately parallel widthwise side surfaces 45 e 2 and 45 e 2 ′ and an end (bottom) surface 46 e 2 . The distance between widthwise side surface 45 e 1 ′ and widthwise side surface 45 m approximately equals the distance between widthwise side surface 45 e 2 and widthwise side surface 45 m′.
Base 42 has an exposed top (upper) surface 47 , two approximately parallel exposed lengthwise side surfaces 48 and 48 ′, two approximately parallel exposed widthwise side surfaces 49 and 49 ′, and two exposed bottom (lower) surfaces 50 and 50 ′ which are staggered in relation to legs 43 . Top base surface 47 and bottom base surfaces 50 and 50 ′ are approximately parallel to leg end surfaces 46 e 1 , 46 m and 46 e 2 and to each other. The three leg end surfaces 46 e 1 , 46 m and 46 e 2 are approximately congruent and approximately coplanar. Lengthwise base side surface 48 and lengthwise leg side surfaces 44 e 1 , 44 m and 44 e 2 are approximately coplanar. Lengthwise base side surface 48 ′ and lengthwise leg side surfaces 44 e 1 ′, 44 m ′ and 44 e 2 ′ are approximately coplanar. Widthwise base side surface 49 and widthwise leg side surface 45 e 1 are approximately coplanar. Widthwise base side surface 49 ′ and widthwise leg side surface 45 e 2 ′ are approximately coplanar.
When appropriately positioned relative to a ferromagnetic surface 11 of ferromagnetic material (e.g., hull plate) 10 , transverse H field component sensor 40 is situated whereby the letter “E” described by E core 41 is sideways adjacent to ferromagnetic surface 11 , so that the three leg end surfaces 45 e 1 , 45 m and 45 e 2 abut ferromagnetic surface 11 . As shown in FIG. 5 and FIG. 7, E core 41 when situated atop ferromagnetic surface 11 is like a letter “E” rotated ninety degrees. Base 42 and ferromagnetic surface 11 , as depicted in FIG. 5 and FIG. 7, are each approximately horizontal. It should be understood, however, that normal B field component sensor 30 and transverse H field component sensor 40 can each be inventively practiced having any orientation in space.
A purpose of the present invention's “E”-shaped transducer core geometry, as defined by E core 41 , is to measure the H component of field intensity in much the same way as would a fluxgate double rod magnetometer or a ring core magnetometer. The drive winding 55 is wound around middle leg 43 m, and applies an H drive field H D which is divided into two H D semiportions corresponding to both lateral ends (viz., the leg 43 e 1 end and the leg 43 e 2 end) of E core 41 .
Sense windings 56 a and 56 b are wound, respectively, over the portions of base 42 having exposed bottom (lower) surfaces 50 and 50 ′, respectively. The amplitude of the induced field in each of sense windings 56 a and 56 b is dependent on the amplitude of (H D +H T ) and (H D −H T ). A simple peak difference demodulator used by the Brown Magnetometer shows that the resultant is equal to 2 H T . A number of detectors could be used, including the amplitude-dependent second harmonic phase detector techniques used by most present high quality fluxgate magnetometers.
Calibration windings 57 are wound over legs 43 m, 43 e 1 and 43 e 2 . The middle calibration winding 57 is wound over drive winding 55 which is directly wound on leg 43 m. A calibration winding 57 is generally necessary for inventive practice of transverse H field component sensor 40 , and would be wound on each of legs 43 m, 43 e 1 and 43 e 2 of E core 41 , to calibrate the changes to absolute field values.
As illustrated in FIG. 7, when transverse H field component sensor 40 is appropriately driven, two closed magnetic flux paths manifest themselves. A first closed magnetic flux path is formed through base 42 , leg 43 e 1 , ferromagnetic material 10 and leg 43 m. A second closed magnetic flux path is formed through base 42 , leg 43 e 2 , ferromagnetic material 10 and leg 43 m.
Still referring to FIG. 5 and also referring to FIG. 8 and FIG. 9, normal B field component sensor 30 employs a Pot core 31 which measures the B N component after spatially averaging out all H T fields. Geometrically, Pot core 31 has a coaxially doubly cylindrical character and bears resemblance to a “pot,” and can be considered to be akin to an E core 41 which is rotated three hundred sixty degrees (360°), thereby canceling out the measured H T component of field. As illustrated in FIG. 9, drive winding 60 applies a B drive field B D wherein (B D +B N )A Outside =(B D −B N )A Inside , wherein A is the amplitude of the induced field.
Although Pot core 31 of normal B field component sensor 30 is a unitary member, for geometrically descriptive purposes Pot core 31 can be considered to be regionalized so as to have a solid disk 32 section, a hollow major cylinder 33 section and (demarcated with respect thereto via intersecting plane b, indicated with dashed line) a solid minor cylinder 34 section. The combination of disk 32 and hollow major cylinder 33 describes a continuous (unbroken) “pot” shape—that is, the shape of a cylindrical container or receptacle.
Disk 32 , hollow major cylinder 33 and solid minor cylinder 34 are approximately coaxial. Otherwise stated, the respective peripheries of disk 32 , hollow major cylinder 33 and solid minor cylinder 34 are approximately symmetrical with respect to the same axis of symmetry a. Disk 32 is approximately circular, and hollow major cylinder 33 and solid minor cylinder 34 are each approximately cylindrical. Hollow major cylinder 33 has an annular bottom surface 35 . Solid minor cylinder 34 has a circular bottom surface 36 . Annular bottom surface 35 and circular bottom surface 36 are approximately coplanar.
Solid minor cylinder 34 has a minor cylindrical surface 37 . As shown in FIG. 5 and FIG. 9, drive winding 60 , sense winding 61 and calibration winding 62 are each wound around minor cylindrical surface 37 in the interior of Pot core 31 . Drive winding 60 is the innermost winding. Sense winding 61 is wound over drive winding 60 . Calibration winding 62 is wound over sense winding 61 . Drive winding 60 and sense winding 61 are only affected by the magnitude of the B N field. As is the case for E core 41 of transverse H field component sensor 40 , a calibration winding 62 is generally necessary for Pot core 31 of normal B field component sensor 30 , so that the amplitude of the component can be measured accurately.
As illustrated in FIG. 9, when normal B field component sensor 30 is appropriately driven, a closed magnetic flux path describing a sort of “donut” shape manifests itself. The closed magnetic flux path is formed through solid disk 32 section, hollow major cylinder 33 section, ferromagnetic material 10 and solid minor cylinder 34 section.
A main feature of the combined transducer in accordance with the present invention is the measurement of the surface B N and H T fields using the ferromagnetic (e.g., hull) material as part of the transducer element. Each of inventive component transducers 31 and 41 individually measures the magnetic condition of the hull and uses it as part of its transducer element. Inventive transducer 30 senses magnetic flux in its Pot core 31 , and inventive transducer 40 senses magnetic flux in its E core 41 . The magnetic state characterized by the hysteresis loop of the ferromagnetic material will be reflected in the value of the surface fields. According to this invention, the normal and tangential magnetic field components can be measured very closely in space with respect to the ferromagnetic surface.
It is believed that no known methodology can accomplish measurement of normal and tangential magnetic field components as well or as easily as can the inventive methodology. Conventional “Hall-effect” sensors would perhaps be capable of measuring B N fields. However, measurement of the H T fields according to known devices and techniques would be difficult and problematical, because this would require modifying the ferromagnetic (e.g., hull) material.
FIGS. 6-5 of the above-mentioned U.S. Navy technical report NSWCCD-TR-98/011 by John F. Scarzello and Edward C. O'Keefe is a photograph of a U.S. Navy tensile testing machine modified to apply stress to a ½″ thick toroidal plate of HY-130. The plate is wound with coils so that a hysteresis curve of toroidal plate can be measured as a function of stress, and correlated with the measurements from the present invention's prototype B N and H T sensors. Ambient fields B are applied normal to the toroidal plate by placing it inside a Helmholtz coil, while H T fields are applied by a separate toroidal calibration winding. In this test installation, the magnetic condition of the test plates can be measured and a comparison made to the prototype inventive sensors.
Experimental ferrite cores, shown in FIGS. 6-4 of the above-mentioned U.S. Navy technical report NSWCCD-TR-98/011 by John F. Scarzello and Edward C. O'Keefe, are being used by the U.S. Navy first to measure the magnetic characteristics of an HY-80 hull sample with a lapped contact surface that is placed in a two-axis Helmholtz coil to test the inventive prototype sensor. Modified electronics from the U.S. Navy's prototype IFM are being used for the U.S. Navy's prototype Pot core 31 and E core 41 . Toroidal core permeability standards, used to periodically check the measurement electronics, are also pictured in FIGS. 6-4 of the above-mentioned U.S. Navy technical report NSWCCD-TR-98/011 by John F. Scarzello and Edward C. O'Keefe. Experimental transducer cores can also be made of laminated silicon steel or other high-induction, soft ferromagnetic materials, and tape wound Pot cores 31 with laminated top disks. Generally speaking, there are numerous transducer core materials that can be used in accordance with this invention, including both crystalline and amorphous material cores. The transducer size will be varied to obtain the desire resolution and dynamic operating range of the material.
Generally, the following are critical issues for inventive practice: (i) calibration; (ii) attachment to the hull or other ferromagnetic material (iii) stability with respect to time and temperature; and, (iv) sensitivity. Regardless of whether the present invention's E core 41 or the present invention's Pot core 31 is being practiced, the interface between the ferromagnetic (e.g., hull) material and the present invention's measuring transducer core normally is critical. Referring again to FIG. 5, FIG. 7 and FIG. 9, ferromagnetic material surface 11 must be a “lapped” surface so that there is almost a transparent boundary of appreciable thickness between ferromagnetic material 10 and the present invention's measuring transducer core—either E core 41 or Pot core 31 , as the case may be.
In the real world, an “ideal” interface may be difficult to achieve. Nevertheless, a very thin sheet of soft magnetic material may be used as an interface 70 , and should be satisfactory as long as its thickness is much less than the dimensions of the present invention's measuring transducer core. The use of ferro-fluid type materials may also be possible to ensure a continuous and uniform flux path between the ferromagnetic material 10 and the present invention's measurement transducer core (whether it is Pot core 31 or E core 41 ).
As shown in FIG. 5 through FIG. 7, interface 70 is present between ferromagnetic surface 11 and the three leg end (bottom) surfaces 45 e 1 , 45 m and 45 e 2 . As shown in FIG. 5, FIG. 8 and FIG. 9, interface 70 is present between ferromagnetic surface 11 and the two round bottom surfaces, viz., annular bottom surface 35 and circular unbroken bottom surface 36 . Interface 70 is shown to be thicker in FIG. 9 than in FIG. 7, but this is for illustrative purposes; neither E core 41 nor Pot core 31 would necessarily require a thicker or thinner interface vis-a-vis each other, and such considerations pertaining to interface thicknesses depend on the individual embodiments.
In inventive practice, E core 41 or Pot core 31 will generally be positioned so as to be at least slightly distanced from the surface of the ferromagnetic material being sensed. The inventive IFM and the inventive SIM will each also be at least slightly distanced from the ferromagnetic material surface. Neither the inventive FSMFS, nor the inventive IFM, nor the inventive SIM is dimensionally or configurationally unwieldy; in ship applications, the inventive FSMFS and/or the inventive IFM and/or the inventive SIM can be rather facilely integrated with a ship or submarine hull, giving reliable performance without necessitating inordinate amounts of hull penetrations and conductors. The U.S. Navy envisions embedding or incorporating each of E core 41 or Pot core 31 in a relatively thick coating provided on the ferromagnetic hull, whereby each of sensor 40 and sensor 30 adjoins the ferromagnetic hull surface but is proximately separated therefrom. The inventive IFM and the inventive SIM can also be embedded in the ship's hull in this manner.
Other embodiments of the inventions disclosed herein will be apparent to those skilled in the art from a consideration of this disclosure or practice of the invention disclosed herein. Various omissions, modifications and changes to the principles described may be made by one skilled in the art without departing from the true scope and spirit of the invention which is indicated by the following claims. | A magnetic field sensor, for sensing the transverse component of the magnetic field intensity H, is based on fluxgate magnetometric principles and includes an “E”-shaped magnetic core. A drive winding is wound about the medial leg of the “E” shape. A sense winding is wound about the base of the “E” shape at the two locations between the medial leg and the extreme legs. A calibration winding is wound about each leg. Another magnetic field sensor, for sensing the normal component of the magnetic induction B, is also based on fluxgate magnetometric principles and includes a magnetic core having a sort of coaxial double cylindrical configuration wherein a basket-shaped cylinder encloses a smaller, solid cylinder. A drive winding, then a sense winding, then a calibration winding are wound over the solid cylinder. During operative placement of either inventive sensor in appropriate relation to a ferromagnetic surface, a closed magnetic flux path is manifested through the sensor and the ferromagnetic material; in effect, the ferromagnetic material is made a part of the sensor's transducer core. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to the injection of fluid into oil and gas wells. In particular, this invention relates to the delivery of fluid to a well through a production tree mounted on the well, by injecting the fluid through a mandrel in the production tree.
[0003] 2. Brief Description of Related Art
[0004] The production of oil and gas from some wells may lead to contact between compounds in hydrocarbon rock formations, and those present in oilfield process fluids, such as, for example, seawater. This contact may lead to the formation of “scale”, or salts that clog the formation and inhibit hydrocarbons in the formation from entering the well. Accordingly, scale inhibitors are sometimes introduced into a well to control or prevent scale deposition. In some cases, scale inhibitors may be combined with fracture treatments, whose purpose is to crack the formation and facilitate the release of hydrocarbons into the well.
[0005] The fluids used to inhibit scaling and to cause fracturing (hereinafter referred to as scale squeeze fluid, or just fluid) are typically introduced to the well through the choke of a production tree attached to the well. From the choke, the fluid may enter the production bore of the tree, the production tubing of the well, and ultimately the formation in need of de-scaling/fracturing. However, there are problems associated with introducing the fluid through a choke on the production tree.
[0006] For example, when the fluid is introduced through the choke, the capacity of the choke to carry out other functions, such as managing pressure within the well, may be reduced or eliminated. In addition, introduction of the fluid through the choke requires a special choke insert adapted for interface with a landing module that delivers the fluid. Retrofitting the choke to accept the special choke insert can be a complicated process that requires multiple steps. The steps include running guide posts, running a remote component replacement (RCR) tool to remove any old choke inserts, running an RCR tool to insert the special choke insert, running a scale squeeze module, injecting the scale squeeze fluid, recovering the module, and capping the scale squeeze adapter.
[0007] Accordingly, there is a need for a fluid injection system and process that overcomes the disadvantages of the prior art.
SUMMARY OF THE INVENTION
[0008] Disclosed herein is a fluid injection system in which the fluid is injected not into the choke of a production tree, but directly into a mandrel at the top of the tree. A pathway is provided within the production tree for the fluid to travel from the mandrel to the production bore within the tree, and then into the production tubing of a well.
[0009] Also disclosed herein is a process for injecting fluid into a well by injecting the fluid. directly into the mandrel at a production tree mounted to the well. The process includes attaching a fluid supply line to the mandrel of the production tree with a connector. In one embodiment, all of the components necessary to connect the fluid supply line to the mandrel, and to control the flow of fluid through the fluid supply line, are included in one package, so that installation of the fluid injection system requires only one trip to deliver the package and install the components of the system at the production tree.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention will be better understood on reading the following detailed description of nonlimiting embodiments thereof, and on examining the accompanying drawings, in which:
[0011] FIG. 1 is a schematic side cross-sectional view of an example embodiment of a production tree having a flow path from a mandrel at the top of a production tree to a production bore in the tree; and
[0012] FIG. 2 is a schematic side cross-sectional view of an example embodiment of a fluid injection system arranged and designed to deliver a fluid to a mandrel at the top of a production tree.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] The system and method of the present disclosure will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown, and wherein like reference numerals refer to like elements throughout. The subject matter of the present disclosure may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments; 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.
[0014] It is to be understood that the subject of the present disclosure is not limited to the exact details or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there are disclosed illustrative embodiments of the subject disclosure and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation.
[0015] Referring to FIG. 1 , there is shown a schematic side cross-sectional view of a production tree 2 according to one possible embodiment of the present invention. The production tree 2 has a production bore 4 in fluid communication with, and configured for attachment at a lower end to, the production tubing of a well (not shown). The production tree 2 also includes a mandrel 6 at an upper end. A fluid port 8 provides a pathway through the mandrel 6 to an annulus wing block through annulus access valve 10 , and from the annulus access valve 10 to a crossover port 12 . An annulus master valve 14 separates the crossover port 12 from the portion of the annulus below the annulus master valve 14 .
[0016] The crossover port 12 provides a pathway from the annulus wing block to a production wing block through a crossover valve 16 . The crossover port 12 intersects the production bore 4 at a location between a production wing valve 18 and a production master valve 20 . The production wing valve 18 separates the crossover port 12 from the portion of the production bore upstream of the production wing valve 18 . Each of the valves disclosed herein may be controlled by known methods. For example, the valves may be hydraulically controlled. Alternatively, the valves may be mechanically or electrically controlled.
[0017] One advantage to the production tree configuration shown in FIG. 1 is that fluid, such as, for example, scale squeeze fluid, may be introduced directly to the production bore 4 through the mandrel 6 of the production tree 2 . One reason this direct injection through the mandrel 6 is advantageous is that it eliminates the need to introduce the fluid through a choke. This frees the choke for use for other purposes, such as controlling pressure within the well. Another advantage to introducing fluid to the production tree directly through the mandrel, and not the choke, is that when connecting the fluid lines, it is easier to land the connector (discussed in more detail below) on the mandrel than the choke.
[0018] FIG. 2 shows a schematic side cross-sectional view of a fluid injection system according to an embodiment of the present invention, where the fluid is introduced to the production tree 2 through a mandrel 6 at the top of the production tree 2 . As can be seen, fluid may be brought to the fluid injection system by a fluid supply line 22 that connects the fluid injection system with a fluid source at another location (not shown), such as, for example, at the surface of the sea. The fluid supply line 22 communicates with the production tree 2 via a connector 24 . In an example embodiment, the connector 24 is annular and includes clamps (not shown) on an inner circumference that can selectively attach on the outer circumference of the mandrel 6 of the production tree 2 . In one embodiment, the connector 24 may be a MDH4 connector. The connector 24 is optionally adaptable for use with different function packages. addition, different connectors may be used to connect the fluid supply line 22 to different types of production trees. For example, although the production tree shown in FIG. 1 is a horizontal tree, the fluid injection system of the present invention may also be used with trees having a vertical configuration.
[0019] As shown in FIG. 2 , the fluid supply line 22 may include one or more valves to control the flow of fluid through the supply line 22 . For example, the fluid supply line 22 may include an isolator valve 26 and/or a check valve 28 , in addition, the fluid injection system may include additional components depending on the type and structure of the production tree 2 . For example, if the production tree has a plug 30 in the top of the mandrel 6 , the system may include a plug removal tool 32 such as that disclosed in, for example, U.S. Pat. Nos. 7,240,736 and 6,968,902. Similarly, a remotely operated vehicle (ROV) carrier 34 may be included in the system. Furthermore, the fluid injection system may include safety devices, such as, for example, an emergency quick disconnect 36 to ensure a secure disconnect.
[0020] One advantage to the fluid injection system shown in FIG. 2 is that all of the necessary structure (e.g., the supply line 22 , isolator valve 26 , check valve 28 , emergency quick disconnect 36 , ROV carrier 34 , plug removal tool 32 , and connector 24 ) can be placed in one trip, with just one land and lock of the connector. Thus, installation of the system of FIG. 2 is faster and more cost effective than the installation of known systems, many of which require running multiple parts and tools separately in order to connect fluid supply lines to the production tree.
[0021] With the structure of the production tree 2 and fluid injection system as shown in FIGS. 1 and 2 , the flow path of fluid introduced through the system is as follows: First, the fluid travels from a fluid source to the connector 24 via fluid supply line 22 . Then the fluid travels through the connector 24 and the mandrel 6 via the fluid port 8 . The annular access valve 10 is open and the annulus master valve 14 is closed, so that the fluid travels through the annular access valve 10 and into the crossover port 12 . Thereafter, with the crossover valve 16 open, the production access valve 18 closed, and the production master valve 20 open, the fluid travels through the crossover valve 16 and the production master valve 20 into the production bore 4 . Thus, the fluid enters the production tree 2 through the mandrel 6 and ultimately into the production bore 4 . From the production bore 4 the fluid travels into the production tubing of the well.
[0022] Another embodiment of the invention includes a method of injecting fluid into the production tubing of a well by introducing the fluid through a mandrel at the top of a production tree. First, the production tree is positioned at the top of the well, so that the production bore of the tree is in fluid communication with the production tubing in the well. In one embodiment, the production tree is designed as described above in reference to FIG. 1 , with a flow path between a mandrel at the top of the tree and the production bore of the tree. A fluid supply line, such as that described above with respect to FIG. 2 , is attached to the mandrel of the production tree. Thereafter, fluid is injected through the mandrel, into the production tubing of the tree, and then from the tree into the production tubing of the well. In one embodiment, the liquid may be scale squeeze liquid, although other types of fluid may he introduced by the same method.
[0023] While the invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention. For example, in addition to the parts of the production tree specifically discussed above, other known tree components may be included in the tree. For example, the tree may include chokes, hydraulic or electric control tines for the valves, etc. Similarly, this system can be integrated with other deep water packages. Furthermore, it is to be understood that the above disclosed embodiments are merely illustrative of the principles and applications of the present invention. Accordingly, numerous modifications may be made to the illustrative embodiments and other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | A system for injecting fluids into a well having a fluid supply tine that is connected to a mandrel at the top of the production tree. The system is designed so that all components of the system are packaged together and run to the production tree in one run. The production tree is designed to provide a pathway for the fluid to travel from the mandrel to the production bore within the tree, and then into the production tubing of a well. | 4 |
TECHNICAL FIELD
The present disclosure generally pertains to a seal between relatively movable parts and more particularly to a tandem dry gas seal suitable for use with a centrifugal compressor.
BACKGROUND
Seal systems are used in a wide variety of rotary shaft devices, such as blowers, compressors, and pumps, which have critical sealing requirements. Dry gas seal systems provide a barrier between the gas in the working chamber, or process gas, and the external environment to minimize the loss of process gas to the environment. Seal systems may include two stages of seals arranged in tandem to improve reliability. Mosley and Haynes, in European Patent Application publication EP 0 701 074 A1, describe a dry gas seal with two face seal stages of the same construction.
Dry gas seals operate with very small gaps or separations between opposed sealing surfaces. Brittle materials such silicon or tungsten carbide are used for some sealing surfaces to provide precise surfaces for small separations between the opposed sealing surfaces. Such materials may, however, fail and a failure can be catastrophic.
The present disclosure is directed toward overcoming one or more of the problems discussed above as well as additional problems discovered by the inventor.
SUMMARY OF THE DISCLOSURE
A seal assembly includes a primary seal stage and a secondary seal stage. The primary seal stage includes a primary ring arranged to be coupled to a housing and a mating ring arranged to be coupled to a rotating shaft. The primary ring and the mating ring of the primary seal stage are formed materials chosen to effectively block flow of gas through the seal assembly. The secondary seal stage is coaxially positioned with respect to the primary seal stage and includes a primary ring arranged to be coupled to the housing and a mating ring arranged to be coupled to the rotating shaft. The primary ring and the mating ring of the secondary seal stage are formed of materials chosen to survive a failure of the primary seal stage. The seal assembly may be used in a compressor for sealing a penetration of the compressor's shaft through the compressor's housing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway illustration of an exemplary centrifugal compressor.
FIG. 2 is a cross-sectional view of a seal assembly according to an exemplary disclosed embodiment.
DETAILED DESCRIPTION
FIG. 1 is a cutaway illustration of an exemplary centrifugal compressor 100 . Process gas enters the centrifugal compressor 100 at a suction port 112 formed on a housing 110 . The process gas is compressed by one or more centrifugal impellers 122 mounted to a shaft 120 . The compressed process gas exits the centrifugal compressor 100 at a discharge port 114 that is formed on the housing 110 .
The shaft 120 and attached elements such as the centrifugal impellers 122 are supported by bearings 132 installed on axial ends of the shaft 120 . Seal assemblies 142 are disposed about the shaft 120 inward of the bearings 132 . The seal assemblies 142 seal high pressure inside the centrifugal compressor 100 . Different designs may use more or fewer seal assemblies 142 .
The seal assemblies 142 include primary and secondary seal stages. The primary seal stage normally operates to block the flow of the process gas out of the compressor. The secondary seal stage may be considered a backup to block the flow of the process gas out of the compressor in the event of failure or malfunction of the primary seal stage. In an embodiment, the secondary and primary seal stages are substantially identical but formed of different materials.
FIG. 2 is a cross-sectional view of a seal assembly 142 . The elements of the seal assembly are generally ring shaped or radially disposed about a central axis of the seal assembly. FIG. 2 illustrates a cross-section of one side of a symmetrical seal assembly. The seal assembly may be used as the seal assemblies 142 of the centrifugal compressor 100 of FIG. 1 . The seal assembly of FIG. 2 includes a primary seal stage 30 and a secondary seal stage 50 . The primary seal stage 30 is disposed at an inner, or process gas, end of the seal assembly 142 . The secondary seal stage 50 is disposed at an outer, or bearing, end of the seal assembly 142 .
The seal assembly is illustrated in FIG. 2 adjacent to a buffer seal 20 . The buffer seal 20 includes segmented carbon rings 21 , 22 held in a buffer seal housing 24 . Radial passages in the buffer seal housing 24 provide a purge inlet 15 . A secondary vent 17 is disposed between the buffer seal 20 and the secondary seal stage 50 . A primary vent 13 is disposed between the primary seal stage 30 and the secondary seal stage 50 . A primary inlet 11 is disposed on the process gas end of the primary seal stage 30 .
When the seal assembly illustrated in FIG. 2 is used in a compressor, various gas flows exist during operation. In an embodiment, filtered process gas 12 flows into the primary inlet 11 . Some of the filtered process gas leaks through the primary seal stage 30 . The filtered process gas that leaks through the primary seal stage 30 passes out the primary vent 13 as a primary vent gas 14 which may then be collected or, for example, for natural gas, flared off. A purge gas 16 , such as nitrogen, flows into the purge inlet 15 . Some of the purge gas flows past the segmented carbon ring 22 and out the secondary vent 17 as a secondary vent gas 18 . Some of the filtered process gas that leaked through the primary seal stage 30 also leaks through the secondary seal stage 50 and out the secondary vent 17 .
The flows through or pressures in the primary inlet 11 , the primary vent 13 , the purge inlet 15 , and the secondary vent 17 are monitored to control operation of the seal. The monitoring can also be used to detect a malfunction or abnormal operation of the seal. A system monitoring the seal can shut down the compressor when abnormal operation is detected.
The primary seal stage 30 includes a sleeve 5 . The sleeve 5 may be coupled to the shaft of a compressor. The sleeve 5 may be formed of a stainless steel. A mating ring 32 is disposed in an opening of the sleeve 5 . A sleeve O-ring 33 is disposed in a slot in the opening of the sleeve 5 . The sleeve O-ring 33 provides a static seal between the sleeve 5 and the mating ring 32 . The sleeve O-ring 33 may be made of a polymer, for example, polytetrafluoroethylene (PTFE).
The primary seal stage 30 also includes a primary ring 31 disposed in an opening of a retainer 34 . The retainer 34 may be formed of a stainless steel. The retainer 34 may be coupled to the housing of a compressor. The primary ring 31 and the mating ring 32 include corresponding opposing faces.
A spring 35 biases the primary ring 31 towards the mating ring 32 . Although one spring is illustrated in FIG. 2 , the primary seal stage 30 may have multiple springs circumferentially distributed around the central axis of the seal assembly 142 . The spring 35 may be formed of a superalloy. A spring plate 36 is disposed between the spring 35 and the primary ring 31 . A retainer O-ring 37 is disposed between the spring plate 36 and the retainer 34 and provides a static seal between the spring plate 36 and the retainer 34 . The retainer O-ring 37 may be made of a polymer, for example, PTFE.
The mating ring 32 of the primary seal stage 30 is made of a brittle material. In an embodiment, the primary ring 31 of the primary seal stage 30 is also made of a brittle material. The primary ring 31 and the mating ring 32 may be made of the same material or different materials. The primary ring 31 and mating ring 32 of the primary seal stage 30 may be coated with additional materials, for example, the rings may be diamond coated. In another embodiment, the primary ring 31 is made of a more flexible material, such as a carbon composite. Brittle materials provide precise shapes that experience limited distortion during operation at high gas pressures, for example, 1000 PSI, high rotational speeds, for example, 20,000 RPM, and high temperatures, for example, 400° C.
Ductile and brittle materials are distinguished by the relationships between stresses and strains in the materials. Ductile materials can withstand relatively large strains before failure. Objects made of either type of material exhibit elastic deformation in response to initial stresses. When stresses are removed after elastic deformation, the objects return to their initial shapes.
Objects made of ductile materials exhibit plastic deformation in response to stresses greater than an elasticity limit. When stresses are removed after plastic deformation, the objects do not return to their initial shapes. Plastic deformation can result in a large deformation in a ductile material, for example, 15%, before the material fractures. An example ductile material is steel. A material may be considered ductile when it can be deformed more than 5% in plastic deformation.
Objects made of brittle materials do not exhibit large plastic deformations. Objects made of brittle materials abruptly fracture in response to stresses greater than a fracture limit. Example brittle materials include tungsten carbide and silicon carbide. A material may be considered brittle when it can be deformed less than 5% before fracture.
The secondary seal stage 50 includes a portion of the sleeve 5 in the embodiment of FIG. 2 . In other embodiments, the secondary seal stage 50 may include a separate sleeve. The secondary seal stage 50 includes a mating ring 52 disposed in an opening of the sleeve 5 . A sleeve O-ring 53 is disposed in a slot in the opening of the sleeve 5 . The sleeve O-ring 53 provides a static seal between the sleeve 5 and the mating ring 52 . The sleeve O-ring 53 may be made of a polymer, for example, PTFE.
The secondary seal stage 50 also includes a primary ring 51 disposed in an opening of a retainer 54 . The retainer 54 may be formed of a stainless steel. The retainer 54 may be coupled to the housing of a compressor. The primary ring 51 and the mating ring 52 include corresponding opposing faces.
A spring 55 biases the primary ring 51 towards the mating ring 52 . Although one spring is illustrated, the secondary seal stage 50 may have multiple springs circumferentially distributed around the central axis of the seal assembly 142 . The spring 55 may be formed of a superalloy. A spring plate 56 is disposed between the spring 55 and the primary ring 51 . A retainer O-ring 57 is disposed between the spring plate 56 and the retainer 54 and provides a static seal between the spring plate 56 and the retainer 54 . The retainer O-ring 57 may be made of a polymer, for example, PTFE.
The mating ring 52 of the secondary seal stage 50 is made of a ductile material, for example, steel. In an embodiment, the primary ring 51 of the secondary seal stage 50 is also made of a ductile material. The primary ring 51 and the mating ring 52 may be made of the same material or different materials. The primary ring 51 and the mating ring 52 of the secondary seal stage 50 may be strengthened by surface treatment, for example, using induction heating. In another embodiment, the primary ring 51 is made of a more flexible material, such as a carbon composite.
INDUSTRIAL APPLICABILITY
The rate that gases leak between the sealing faces of the primary ring 31 and the mating ring 32 is decreased when the faces are closely spaced. The primary ring 31 and the mating ring 32 may be spaced, for example, by a few microns. The components of the seal assembly 142 are subject to shape distortion by thermal changes, gas pressures, and rotational forces.
Prior seal assemblies have used primary and secondary seal stages made of the same materials. Early seal assemblies used mating rings, in both primary and secondary seal stages, made of steel, a ductile material. The seal assemblies used primary rings, in both primary and secondary seal stages, made of a carbon composite material. The carbon composite used is relatively flexible (having a low modulus of elasticity) and low strength compared to the mating ring. The carbon composite is also quite brittle. The carbon composite, because of its low strength, is generally not used as for the mating ring, which rotates.
For use at higher pressures, prior seal assemblies use mating rings, in both primary and secondary seal stages, made of tungsten carbide or silicon carbide, brittle materials. The relatively flexible primary rings conformed against the much stiffer mating rings creating the desired small spacing between the faces of the primary and mating rings. For use at still higher pressures, other prior seal assemblies use mating rings and primary rings, in both primary and secondary seal stages, made of tungsten carbide or silicon carbide.
A seal assembly using a carbide mating ring and a carbon primary ring can fail when the highly stressed mating ring develops cracks due to thermal, rotational, and pressure induced stresses. When the mating ring fails, the carbide material can break up into pieces with jagged edges. With rotation, these pieces can cut into and break up the carbon primary ring causing destruction of the primary ring.
The carbon primary ring is not typically considered the initiator of a failure. If the carbon primary ring were to crack first, since it has low strength, it would not cause another ring to crack and break up. Although the gas flow would increase due to the cracks in the carbon ring, the flow would still be low compare to when pieces of the rings are liberated opening up large flow paths.
A seal assembly using a carbide mating ring and a carbide primary ring can fail in the same manner. Breakup of one of the carbide rings liberates hard pieces which can cause the other carbide ring to fail.
The present seal assembly 142 uses materials in the primary seal stage 30 and the secondary seal stage 50 selected for the distinct functions of the stages. The seal assembly is both very effective at blocking the flow of gases and very rugged. The primary seal stage 30 is effective at blocking flow of gases. The primary seal stage 30 may [add example of seal performance]. The ruggedness of the secondary seal stage 50 can allow it to survive a failure of the primary seal stage.
The materials used in the primary ring 31 and the mating ring 32 of the primary seal stage 30 are selected for their superior performance as a gas seal. For intermediate to high gas pressures at least one of the rings is a rigid material like silicon carbide or tungsten carbide. In some embodiments, both the primary ring 31 and the mating ring 32 are made of these types of materials. Although these materials provide superior seal performance at elevated pressures, in the event of a failure, fracturing and liberation of pieces of these rigid, brittle materials often results in large openings within the seal assembly, which causes excessive amounts of pressurized gas to escape.
The materials used in the primary ring 51 and the mating ring 52 of the secondary seal stage 50 are selected for their ruggedness in the event of a failure of the primary seal stage 30 in addition to performance as a gas seal. The use of a ductile material, like steel, in the highly stressed rotating mating ring 52 mitigates the possibility of pieces of the mating ring 52 being liberated as in the case of a brittle material failure. In various embodiments, the primary ring 51 is made from a ductile material or a carbon material, which is a relatively flexible although somewhat brittle. These materials result in the primary ring remaining more intact and in place after a failure than rings made of the materials used in the primary seal stage.
The disclosed seal assembly embodiments may be suited for any number of industrial applications, such as various aspects of the oil and natural gas industry. For example, applications for compressors with the disclosed seal assemblies may include transmission, gathering, storage, withdrawal, and lifting of oil and natural gas.
The seal assemblies discussed above may be used in servicing a compressor in the field. An existing seal assembly may be removed and replaced with a new seal assembly. The new seal assembly is of a type disclosed above.
The preceding detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. The described embodiments are not limited to use in conjunction with a particular type of compressor. Hence, although the present disclosure, for convenience of explanation, depicts and describes a seal assembly for a centrifugal compressor, it will be appreciated that seal assemblies in accordance with this disclosure can be implemented in various other configurations and used in other types of machines. Furthermore, there is no intention to be bound by any theory presented in the preceding background or detailed description. It is also understood that the illustrations may include exaggerated dimensions to better illustrate the referenced items shown, and are not consider limiting unless expressly stated as such. | A seal assembly forms a barrier between a compressor's interior and exterior regions. The seals assembly includes a primary seal stage and a secondary seal stage. The primary seal stage is formed of materials chosen to effectively block flow of gas through the seal assembly. The secondary seal stage is formed of materials chosen to survive a failure of the primary seal stage. | 5 |
FIELD OF THE INVENTION AND RELATED ART STATEMENT
1. Field of the Invention
The present invention relates to a brushless DC motor which is suitable for a laser printer, a polygon scanner for facsimile or the like.
2. Description of the Related Art
The conventional brushless DC motor in the prior art is provided with exciting multiphase windings with semiconductor switches connected to the respective exciting windings, wherein the direction of current flowing in the exciting windings is switched in response to the relative position between a rotor made of a permanent magnet and the exciting windings. By changing the current direction and by selecting suitable windings, a torque for a constant rotative direction is generated. However, in such a brushless DC motor of the prior art, when the currents of the windings are switched for selection of the windings, a discontinuous fluctuation of the torque which is peculiar to the conventional brushless DC motor arises. In order to reduce the peculiar fluctuation of the torque, it is desirable, for example, to increase the inertia of the rotative member or to control the phase and the value of the exciting current with a driving circuit, so as to compensate the fluctuation of the torque.
A brushless DC motor which is equivalent to the two-phase excitation in alternating current and which is excited using a transistor switch is shown in FIG. 8 as a conventional example in the prior art. Referring to FIG. 8, a stator 1 is provided with four slots 3, and exciting windings 4, 4', 5 and 5' are wound in the respective slots 3. A rotor 2 which is magnetized into two poles of N and S is rotatably mounted in the central opening of the stator 1 with the shaft 6. Although a rotor 2 having one pole pair is shown by way of Example in the related art description for simplicity, the electric angle of a unit pole pair will be 2π even if the rotor has multipole pairs.
Respective direct current switches Tr 11 , Tr 12 , Tr 21 and Tr 22 are connected in series with the exciting windings 4, 4', 5 and 5', respectively. A positive terminal of a direct current power source 7 is connected to one end of the windings 4 and 4'. Another end of the windings 4 and 4' is connected to the negative terminal of the DC power source 7 through the respective DC current switches Tr 11 and Tr 12 . Since the direct current switches Tr 11 -Tr 22 allow a current to pass in a predetermined direction when closed, for example, when a current flows into the exciting winding 4 which is connected to the direct current switch Tr 11 by closing the direct current switch Tr 11 , a portion 1a of the stator 1 wound with the exciting winding 4 is magnetized to N of the magnetic pole, which is identical with the N pole of the rotor 2. On the other hand, when the direct current switch Tr 12 closes, a current flows into the exciting winding 4', and a portion 1b of the stator 1 wound with the winding 4' is magnetized to the N pole. As a result, the magnetic pole of the portion 1a of the stator 1 wound by the exciting winding 4 becomes N by turning ON the direct current switch Tr 11 , and becomes S by turning ON the direct current switch Tr 12 . On the contrary, the magnetic pole of the portion 1b of the stator 1 wound with the exciting winding 4' becomes S by turning ON the direct current switch Tr 11 , and becomes N by turning ON the direct current switch Tr 12 . The changes of the magnetic poles as mentioned above are substantially identical with a change of magnetic poles of a single exciting winding in alternating current excitation. Effects which are caused by the exciting windings 5 and 5' and are respective direct current switches Tr 21 and Tr 22 are similar to that of the exciting windings 4 and 4' and the direct current switches Tr 11 and Tr 12 . These effects are substantially equivalent to the two-phase excitation in the alternating current excitation.
Positional sensors H 1 , H 2 , H 1 ' and H 2 ' are disposed in the respective slots 3 and detect a position of the magnetic pole of the rotor 2. The respective positional sensors H 1 , H 2 , H 1 ' and H 2 ' are connected to the direct current switches Tr 11 , Tr 21 , Tr 12 and Tr 22 , respectively. Signals for controlling the exciting windings 4, 4', 5 and 5' in relation to the magnetic pole of the rotor 2 are generated by the positional sensors H 1 , H 2 , H 1 ', H 2 ', respectively. The positional sensors H 1 , H 2 , H 1 ' and H 2 ' may be composed by a Hall device, for example. During operation of the positional sensors, when the N pole of the rotor 2 approaches the positional sensor H 1 , a voltage is induced in the positional sensor H 1 and the direct current switch Tr 11 closes. By contrast, induced voltage in the positional sensor H 1 ' is reduced and the direct current switch Tr 12 is opened. The above-mentioned action also arises in the positional sensors H 2 and H 2 ' at the position wherein the rotor 2 turns by 90° from the positions mentioned above, and in this case the direct current switch Tr 21 closes and the direct current switch Tr 22 opens. As a result, the exciting windings 4, 4', 5 and 5' are switched in turn by rotation of the rotor 2 about shaft 6.
The relationship between the magnetic poles generated by the exciting windings 4, 4', 5 and 5' and the rotor 2 is shown in FIG. 9(a). In the figure, the magnetic poles of the stator 1 excited by the respective exciting windings 4, 4', 5 and 5' and the rotor 2 are shown by linearly spread bars. Referring to FIG. 9(a), the magnetic poles 14 and 14' of the stator 1 excited by the exciting windings 4 and 4' coincide with the magnetic poles 12 of the rotor 2, which are shown in the third line of FIG. 9(a). In this state, on the other hand, the magnetic poles 15 and 15' of the stator 1 excited by the exciting windings 5 and 5' are displaced from the magnetic poles 12 of the rotor 2 by π/2 as shown in the middle line of FIG. 9(a). The positions of the respective positional sensors H 1 , H 2 , H 1 ' and H 2 ' are as shown at the bottom line.
A variation of the torque corresponding to the rotational angle of the rotor 2 is shown in the waveforms of FIG. 9(b). A waveform T 1 shows a torque generated by the magnetic poles 14 and 14', and a waveform T 2 shows a torque generated by the magnetic poles 15 and 15'. A waveform (T 1 +T 2 ) shows a resultant torque of the magnetic poles 14, 14', 15 and 15'. The waveform (T 1 +T 2 ) shows that the exciting windings 4, 4', 5 and 5' are switched during the rotational angle of π of the rotor 2. Furthermore, it is shown that the phase difference between the exciting windings 4 and 4' and the exciting windings 5 and 5' is π/2. The above-mentioned operation is known as the current flowing for a π electric degrees in the brushless motor.
When the gap between stator 1 and rotor 2 is uniform and a reluctance torque does not exist, and when the windings are simply excited by a switched DC source, the excited magnetic flux distribution of the stator 1 per one unit length of axis direction is shown by the following expression:
B.sub.s ·sin θ,
and a magnetic flux distribution of the rotor magnet per one unit length for axial direction is shown by the following expression:
B.sub.R sin (θ-ωt-ψ),
where θ designates a space distribution angle, B s designates a maximum value of excited magnetic distribution, ωt designates an angular velocity of rotation, B R designates a maximum value of a magnetic flux distribution of the rotor and ψ designates an initial difference of positions or a load angle between the stator 1 and the rotor 2. A magnetic energy W which is stored in the gap is shown by the following equation (1): ##EQU1## where, R designates a reluctance.
Therefore, a torque T which is generated by exciting the respective exciting windings 4, 4', 5 and 5' is shown by the following equation (2): ##EQU2##
When a spatial harmonics magnetic flux distribution exists in the magnetic flux distribution, a torque Tn by the harmonics magnetic flux is generated only when the harmonic magnetic flux distribution of the same dimension exists as shown by the equations (1) and (2), the torque Tn being introduced by combination of the equation (1) and (2), and being shown by the following equation (3):
Tn=-2πRnB.sub.Sn B.sub.Rn sin n(ωt+ψ) (3),
where Bsn designates a maximum value of an excited magnetic flux distribution of an n harmonic, BRn designates a maximum value of an excited magnetic flux distribution of the rotor of an N harmonic and Rn designates the reluctance of an n harmonic.
In the above-mentioned operation, currents are continuously flowed in the exciting windings 4, 4', 5 and 5', and the flows of the currents are controlled by the positional sensors H 1 , H 1 ', H 2 and H 2 ' for sensing the magnetic pole of the rotor 2. Therefore, the torque Tn between the magnetic poles 14, 14', 15 and 15' and the rotor 2 as shown in the equation (3) is maintained within the rotational angle from 0 to π in the current flow for π electric degrees.
In a brushless DC motor of the prior art comprising two-phase exciting windings and a rotor operating in the current flow for π/2 electric angle, as shown in FIG. 10(a), when one exciting winding is excited, another exciting winding is controlled so as not to be excited by utilizing the positional sensors H 1 , H 2 , H 1 ' and H 2 '. The exciting windings are excited with a time period of π/2 in turn. Therefore, in this prior art motor, the torque fluctuates with a time period of π/2 as shown by the curve T of FIG. 10(b), and there is a specialized torque variation in two-phase exciting of the current flow for π/2 electric degrees.
FIG. 11(a)-FIG. 11(d) show an example of a brushless DC motor in the prior art having three-phase exciting windings. FIG. 11(a) shows exciting polarities of the respective exciting windings, and FIG. 11(b) shows the polarity of the rotor wherein the pole N of the rotor coincides with the polarity of the first windings. The positional sensors H 1 , H 2 , H 3 , H 1 ', H 2 ' and H 3 ' are disposed at the positions as shown in FIG. 11(c). The torque characteristic in the current flowing for π/3 electric degrees of the example is shown in FIG. 11(d). The torques T 1 , T 2 and T 3 as shown by dotted lines are generated by the first winding, the second winding and the third winding, respectively. The sum torque is shown by the envelope TE. As is shown by the envelope TE, the torque of the three-phase brushless DC motor also considerably varies with an electric angle π/3 which is peculiar therein.
OBJECT AND SUMMARY OF THE INVENTION
An object of the present invention is to provide a brushless DC motor wherein fluctuation of the torque is reduced and a flat torque characteristic is realized.
The brushless DC motor for compensating ripple torque in accordance with the present invention comprises:
a stator having exciting windings,
a rotor having main magnetic poles opposing the exciting windings through an air gap,
compensation magnetic poles disposed on the rotor, and
a compensation winding opposing through the air gap the compensation magnetic poles disposed on the rotor, for generating a compensating torque having inverse phase and an identical cyclic period with respect to a variation of torque generated by interaction of the exciting windings and the main magnetic poles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphics depiction of a main torque and a compensation torque in a brushless DC motor of a first embodiment in accordance with the present invention;
FIG. 2 is a plane view of the brushless DC motor of the first embodiment;
FIG. 3 shows the relative position of linearly spread magnetic poles of a stator and rotor and of positional sensors in the first embodiment;
FIG. 4 shows the relative position of linearly spread magnetic poles of the rotor and compensation magnets and of the positional sensors in current flowing for electric degrees in the embodiment;
FIG. 5 shows a magnetization pattern of the rotor in the case of current flowing for π/2 electric degrees of the first embodiment;
FIG. 6 shows a magnetization pattrn of the rotor in the case of current flowing for π electric degrees of the first embodiment;
FIG. 7(a) shows torque characteristics in a three-phase brushless DC motor of a second embodiment in accordance with the present invention;
FIG. 7(b) shows the relative position of linearly spread magnetic poles of the three windings and the compensation winding of the second embodiment;
FIG. 7(c) shows the relative position of linearly spread magnetic poles of compensation magnets and a main rotor of the second embodiment;
FIG. 7(d) shows the linearly spread positions of the positional sensors in the second embodiment;
FIG. 8 is the plan view of a brushless DC motor in the prior art;
FIG. 9(a) shows the relative position of linearly spread magnetic poles of the stator and rotor and of the positional sensors in the prior art;
FIG. 9(b) shows the torque characteristics of the brushless DC motor in the prior art;
FIG. 10(a) shows the relative position of the linearly spread magnetic poles of the stator and rotor in π/2 operation of a two-phase motor in the prior art;
FIG. 10(b) shows the torque characteristics in current flow for π/2 electric degrees of a two-phase motor in the prior art;
FIG. 11(a), FIG. 11(b) and FIG. 11(c) show the relative positions of the linearly spread magnetic poles of the stator and rotor and of the positional sensors in the three-phase operation of the prior art;
FIG. 11(d) shows the torque characteristic in the three-phase operation of the prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention is illustrated in FIG. 1-FIG. 7(d). The basic principle of the present invention is shown in FIG. 1. Referring to FIG. 1, the abscissa indicates a rotational angle represented in radians and the ordinate indicates torque. Curve T 1 shows a torque generated between first windings 8 and 8' and a rotor 2, and curve T 2 shows the torque generated between second winding 9 and 9' and the rotor 2. Curve T, which is an envelope of the curves T 1 and T 2 , shows a sum of the torques as shown by the curves T 1 and T 2 in a current flowing for π/2 electric degrees of a two-phase brushless DC motor. The above-mentioned torque T cyclically varies with a time period of π/2. If a compensation torque as shown by a curve T A is added to the torque T, hill-top shaped portions of the compensation torque T A are added to valley-shaped portions of the torque T, and total torque becomes almost flat because the phase of the compensation torque T A is opposite to that of the torque T and effectively eliminates the hill and vally-shaped portions when added thereto.
A plane view of an embodiment in accordance with the present invention is shown in FIG. 2. A ring shaped stator core 1A has eight slots 3a, 3b, 3c, 3d, 3e, 3f, 3g and 3h on an inner wall thereof. A winding 8 is wound across slots 3a and 3e on the upper portion of the stator core 1A as shown in FIG. 2. A winding 8' is wound also across the slot 3a and 3e on the lower part of the stator core 1A. A winding 9 is wound across slots 3c and 3g on the right portion of the stator core 1A, and a winding 9' is wound acros the slots 3c and 3g on the left portion of the stator 1A. A compensation winding 10 is also inserted in the slot 3a from the front side to the rear side of the stator 1A as shown in FIG. 2. Compensation winding 10 passes behind the stator 1A and is inserted in the slot 3b. Then the winding 10 is pulled out to the front side of the stator 1A. Subsequently, the winding 10 passes the front side of the stator 1A and is inserted in the slot 3c to the rear side of the stator 1A. The remainder of the slots 3d, 3e, 3f, 3g and 3h are likewise filled by the winding 10, and the respective terminals are connected to the power source 7.
One of the terminals of each of the windings 8 and 8' are connected to a negative terminal of a power source 7 through direct current switches Tr 11 and Tr 12 , respectively. One of the terminals of each of the winding 9 and 9' is also connected to the negative terminal of the power source 7 through direct current switches Tr 21 and Tr 22 . The other terminals of the respective windings 8, 8', 9 and 9' are connected to a positive terminal of the power source 7. Positional sensors H 1 , H 2 , H 1 ' and H 2 ' using a Hall devices are disposed in the slots 3f, 3h, 3b and 3d, respectively. The direct current switch Tr 11 is controlled by the positional sensor H 1 , the direct current switch Tr 12 is controlled by the Hall device H 1 ', the direct current switch Tr 21 is controlled by the positional sensor H 2 , and the direct current switch Tr 22 is controlled by the positional sensor H 2 '. A rotor 2A also is formed by a pair of magnetic poles. A ring shaped compensation magnet 2B comprises four pairs of magnetic poles disposed on a peripheral portion of the rotor 2A.
Linearly spread magnetic poles of the brushless DC motor as shown in FIG. 2 are shown by FIG. 3. Since the current of compensation winding 10 is constant, its magnetic poles do not change.
When the rotor 2A rotates, a compensation torque T A which has a reverse phase with respect to the variation of sum torque T of T 1 and T 2 generated between the windings 8, 8', 9, 9' and the rotor 2A is generated. The relationship between the compensation torque and a main torque generated by the windings 8, 8', 9, 9' and the rotor 2A is discussed hereinafter. When the maximum value of the sum torque is 1 as a fundamental value in the current flowing for π electric degrees and the current flowing for π/2 electric degrees, torque at a position where the current is switched is calculated by equation (2), and the value is given by the following equation:
sin π/4=0.707,
Therefore, the compensation torque T A is given by the following equation: ##EQU3##
As a result, the compensation torque T A in the current flow for π/2 electric degrees is shown by equation (4-1).
T.sub.A =0.145 sin 4(ωt-π/8) (4-1).
The compensation torque T A in the current flow for π electric degrees is shown by the following equation (4-2).
T.sub.A =-0.145 sin 4(ωt-π/8) (4-2).
In the embodiment, a torque due to mutual action between the compensation magnets 2B and the stator windings, or a torque due to mutual action between the rotor 2A and the compensation winding 10 is not generated because the number of poles thereof are different from each other.
The relationship between a maximum value B S of a magnetic flux distribution of the stator exciting windings and a maximum value B SA of the magnetic flux distribution of the compensation winding is obtained by equation (2), the relation being shown by the following equation: ##EQU4## where, B S designates a maximum value of the magnetizing distribution of the first stator winding, B R designates a maximum value of the magnetizing distribution of the magnetic pole of the rotor 2A, B SA designates a maximum value of the exciting distribution of the compensation winding and B RA designates a maximum value of the magnetizing distribution of the magnetic pole of the compensation magnet 2B.
For example, when the respective values are as follows: 0.3B R =B RA , B S =1, B R =1 the values V SA may be obtained from equation (5) as shown by the following equation (6): ##EQU5## When the gap between the stator and the rotor is constant and magnetic reluctance is generated by only the gap, an ampere turn of the compensation winding is decided by equation (6). A ratio of the strength of the magnetic pole of the rotor 2A to that of the magnetic poles of the compensation magnet 2B is selected to be of a suitable value by selecting a ratio of both lengths along the axis, when both magnets have the same characteristics.
In the embodiment, since the stator is provided with the four pairs of magnetic poles generated by the compensation winding, the four pairs of magnetic poles are disposed on the rotor with a pitch of an electric angle of π/8 as the compensation magnets in the current flowing for π/2 electric degrees. In the current flowing for π electric degrees, the four pairs of the magnets are disposed in a reverse polarity to that of the current flowing for π/2 electric degrees.
Relative positions between the magnetic poles 24, 24', 25 and 25' and the magnetic poles 20 of the compensation winding of the stator 1A, the magnetic poles 22 and 11 of the rotor 2A and 2B, respectively, and the positional sensors H 1 , H 1 ', H 2 and H 2 ' in the current flow of π/2 electric degrees are shown in FIG. 3, while the relative positions of the magnetic poles of the rotor and the positional sensors in the current flow of π electric degrees are shown in FIG. 4.
When a common magnet is used as the magnet of the rotor 2A and the compensation magnet 2B of the rotor, a magnetizing distribution is formed along the combined magnetic pole of the magnetizing distribution B R sin θ of the rotor and magnetizing distribution ±B RA sin 4(θ+π/8) of the compensation magnet. The magnetizing distribution is given by the following expression:
B.sub.R sin θ±B.sub.RA sin 4 (θ+π/8) (7),
where the plus sign is applied in the current flow for π/2 electric degrees, and the minus sign is applied in the current flow for π electric degrees.
A magnetizing distribution plotted with an interval π/16 in the current flow for π/2 electric degrees is shown in FIG. 5 (a pattern of the magnetizing distribution of B R =1, B RA =0.3). A magnetizing distribution which is plotted with an interval π/16 in the current flow for π electric degrees is shown in FIG. 6 (a pattern of the magnetizing distribution of B R =1, B RA =0.3). In these figures, a sign 0 shows zero magnetizing zones.
The torque characteristics in the case of a three phase brushless DC motor in the current flow for π/3 electric degrees is shown in FIG. 7(a). In the figure, curves T 1 , T 2 and T 3 show torques of a first winding, a second winding and a third winding, respectively. A compensation torque T A is given by the following expression:
0.067 sin 6 (ωt+π/12).
Linearly spread magnetic poles of the first winding, the second winding, the third winding, a compensation winding, a compensation magnetic pole of the rotor and a magnetic pole of the rotor are shown in FIG. 7(b) and FIG. 7(c). Relative positions of the positional sensors for switching currents of the respective windings of the stator are shown in FIG. 7(d).
In a brushless DC motor having m (where m is a natural number) phase exciting windings, a compensation winding having magnetic poles as shown by an expression 2×(2 m) is wound by superimposition on the exciting windings. The compensation winding then is excited by a constant DC current. The number of compensation magnetic poles of the rotor in the m-phase brushless DC motor is also 2×(2m).
Also, when a common magnet is used as the magnet of the rotor and the compensation magnets, the common magnet is magnetized in a magnetizing pattern to an axis direction of the rotor as shown by the following expression:
B.sub.R sin θ+B.sub.RA sin [2×(2 m)θ±π/2].
Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form may be changed in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed. | A brushless DC motor comprising a stator with plural exciting windings and a rotor made of a permanent magnet is provided with a compensation winding wound in the stator and compensation magnetic poles disposed on the rotor such that a torque which is generated between the compensation winding and the compensation magnetic poles of the rotor may eliminate fluctuation of the torque generated by interaction of the exciting windings of the stator and the main magnet of the rotor. | 7 |
RELATED APPLICATIONS
[0001] This application claims the benefit of earlier filed provisional application Ser. No. 61/019,609 filed Jan. 8, 2008 entitled “Method of Mixing Search Results from Multiple Categories.
[0002] This application also relates to five earlier U.S. patent applications, namely Ser. No. 11/189,312 filed 26 Jul. 2005, published as US 2007/00278329, entitled “processing and sending search results over a wireless network to a mobile device”; Ser. No. 11/232,591, filed Sep. 22, 2005, published as US 2007/0067267 entitled “Systems and methods for managing the display of sponsored links together with search results in a search engine system” claiming priority from UK patent application no. GB0519256.2 of Sep. 21, 2005, published as GB2430507; Ser. No. 11/248,073, filed 11 Oct. 2005, published as US 2007/0067304, entitled “Search using changes in prevalence of content items on the web”; Ser. No. 11/289,078, filed 29 Nov. 2005, published as US 2007/0067305 entitled “Display of search results on mobile device browser with background process”; and U.S. Ser. No. 11/369,025, filed 06 Mar. 2006, published as US2007/0208704 entitled “Packaged mobile search results”. This application also relates to US provisional applications Ser. No. 60/946,729 filed Jun. 28, 2007 entitled “Method of Enhancing Availability of Mobile Search Results”, Ser. No. 60/946,730, filed Jun. 28, 2007 entitled “Social distance search ranking”, Ser. No. 60/946,728, filed Jun. 28, 2007 entitled “Ranking Search Results Using a Measure of Buzz”, and Ser. No. 60/946,726, filed Jun. 28, 2007 entitled “Audio Thumbnails”.
[0003] The contents of these applications are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0004] This invention relates to query servers for providing a mobile search service, to corresponding methods of using a mobile search service, and corresponding apparatus and software.
DESCRIPTION OF THE RELATED ART
[0005] Search engines are known for retrieving a list of addresses of documents on the Web relevant to a search keyword or keywords. A search engine is typically a remotely accessible software program which indexes Internet addresses (universal resource locators (“URLs”), usenet, file transfer protocols (“FTPs”), image locations, etc). The list of addresses is typically a list of “hyperlinks” or Internet addresses of information from an index in response to a query. A user query may include a keyword, a list of keywords or a structured query expression, such as Boolean query.
[0006] Known Internet search engines take a query from a user and return a list of search results. A typical search engine “crawls” the Web by performing a search of the connected computers that store the information and makes a copy of the information in a “web mirror”. This has an index of the keywords in the documents. As any one keyword in the index may be present in hundreds of documents, the index will have for each keyword a list of pointers to these documents, and some way of ranking them by relevance.
[0007] For all search engines, the order that results are displayed in will depend on many factors, but are typically derived from at least a measure of how well the search terms matched the candidate documents and some measure of the significance or popularity of those document independent of the search terms. For example, it is known to rank hypertext pages based on intrinsic and extrinsic ranks of the pages based on content and connectivity analysis. Connectivity here means hypertext links to the given page from other pages, called “backlinks” or “inbound links”. These can be weighted by quantity and quality, such as the popularity of the pages having these links. PageRank(™) is a static ranking of web pages used as the core of the search engine known by the trademark Google (http://www.google.com).
[0008] This ranking arrangement works fine for search services where all candidate documents are handled by the same algorithm and displayed in the same manner, e.g. all discoverable web-pages on the Internet but does not lend itself to the situation where there are multiple types of documents, each scored in a type-specific manner and displayed with a type-specific presentation. Other known search engines currently solve this problem by offering the user the choice, up front, of performing a Web search versus an Image search or a Product search. Once this choice has been made, the problem is reduced to the original arrangement whereby results of only one type are being displayed. Other services solve the problem by dividing the results page into multiple regions and displaying a single result-type per region.
[0009] Search engines for searching the world wide web are well developed for accessing the web from a desktop personal computer (i.e. a computer having a keyboard, mouse and display say bigger than 1000×1000 pixels). On a desktop search service, such as Google and Ask.com, such solutions for addressing searches which provide multiple types of documents work reasonably well. Mobile devices that are capable of accessing content on the world wide web are becoming increasingly numerous. Some of the problems of known mobile search services are addressed in US 2007/00278329, US 2007/0067267, US 2007/0067304, US 2007/0067305 and US2007/0208704 to the present applicants and the contents of these applications are herein incorporated by reference.
[0010] The present applicant has realized that further improvements are possible, particularly to address searches which provide multiple types of documents.
SUMMARY OF THE INVENTION
[0011] According to one aspect there is provided a query server to provide a search service for searching computer accessible content, the query server being arranged to
[0012] receive a search query from a user on a mobile device,
[0013] output said search query to multiple sources of indexable information,
[0014] input an individual list of results from each of said multiple sources together with a scoring for each result wherein each result has a position in its associated individual list determined by its scoring,
[0015] combine said lists of results to form a single combined list wherein results in said single combined list are ranked using a combination of their scoring and position in their respective individual list and
[0016] send said combined list of search results to a user's mobile device.
[0017] According to another aspect there is provided a method of providing a search service for searching computer accessible content, the method comprising
[0018] receiving a search query from a user on a mobile device,
[0019] outputting said search query to multiple sources of indexable information,
[0020] inputting an individual list of results from each of said multiple sources together with a scoring for each result wherein each result has a position in its associated individual list determined by its scoring,
[0021] combining said lists of results to form a single combined list wherein results in said single combined list are ranked using a combination of their scoring and position in their respective individual list and
[0000] sending said combined list of search results to a user's mobile device.
[0022] In other words, the results are served in a single combined (mixed list) containing examples from multiple types which is much more beneficial on a mobile handset where the display is perhaps only 200×200 pixels. On such handsets, there is little room to divide up the results into separate regions as proposed for desktop services (although this is the solution adopted currently by e.g. m.yahoo.com) without generating a very long page requiring time-consuming scrolling to view. The invention addresses the difficulty of arranging the scoring of mixed search results, when the factors (e.g. scores and distributions of scores) are type-specific.
[0023] The invention provides an arrangement whereby results of multiple types are mixed in relevancy order. By using both ranking and scoring from the original individual lists, the combined list will have some result diversity across the different types. As explained in more detail below, the arrangement may provide convenient and tunable control over the importance placed upon result diversity.
[0024] Various aspects of the invention are set out in the independent claims. Any additional features can be added, and any of the additional features can be combined together and combined with any of the above aspects. Other advantages will be apparent to those skilled in the art, especially over other prior art. Numerous variations and modifications can be made without departing from the claims of the present invention. Therefore, it should be clearly understood that the form of the present invention is illustrative only and is not intended to limit the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] How the present invention may be put into effect will now be described by way of example with reference to the appended drawings, in which:
[0026] FIG. 1 shows schematically an overview of some of the complete system principal entities involved in an embodiment of the invention,
[0027] FIG. 2 shows a schematic view of some features of the system shown in FIG. 1 ;
[0028] FIG. 3 a shows a schematic view of an alternative mixing engine for use in the system shown in FIG. 1 ;
[0029] FIG. 3 b shows the steps of a method implemented by the mixing engine of FIG. 3 a;
[0030] FIG. 4 a shows a schematic view of a second alternative mixing engine, and
[0031] FIG. 4 b shows the steps of a method implemented by the mixing engine of FIG. 4 a.
DETAILED DESCRIPTION
DEFINITIONS
[0032] Online means accessible by computer over a network and so can encompass accessible via the internet or public telecommunications networks, or via private networks such as corporate intranets.
[0033] Content items encompasses web pages, or extracts of web pages, or programs or files such as images, video files, audio files, text files, or parts of or combinations of any of these and so on.
[0034] User can encompass human users or services such as meta search services.
[0035] Items which are “accessible online” are defined to encompass at least items in pages on websites of the world wide web, items in the deep web (e.g. databases of items accessible by queries through a web page), items available internal company intranets, or any online database including online vendors and marketplaces.
[0036] Hyperlinks are intended to encompass hypertext, buttons, softkeys or menus or navigation bars or any displayed indication or audible prompt which can be selected by a user to present different content.
[0037] The term “comprising” is used as an open-ended term, not to exclude further items as well as those listed.
DETAILED DESCRIPTION OF THE DRAWINGS
[0038] The overall topology of the embodiments of the invention is illustrated in FIG. 1 which shows a mobile search service deployed using the normal components of a search engine. The search engine service is deployed using the query server 50 to prompt for and respond to queries from users. The indexer 60 populates the index 70 containing word occurrence lists (commonly referred to as inverted word lists) together with other meta-data relevant to scoring. The back-end crawler 80 scans for and downloads candidate content (“documents”) from the web (or other source of indexable information). This system can be formed of many servers and databases distributed across a network, or in principle they can be consolidated at a single location or machine. The term search engine can refer to the front end, which is the query server in this case, and some, all or none of the back end parts used by the query server, whose functions can be replaced with calls to external services.
[0039] A plurality of users 5 connected to the Internet via desktop computers 11 or mobile devices 10 can make searches via the query server. The users making searches (‘mobile users’) on mobile devices are connected to a wireless network 20 managed by a network operator, which is in turn connected to the Internet via a WAP gateway, IP router or other similar device (not shown explicitly). The search results sent to the users by the query server can be tailored to preferences of the user or to characteristics of their device.
[0040] The documents fetched and supplied to the indexer 60 can be of numerous different types, e.g. images, music files, restaurant reviews, wikipedia™ pages. For each type of document, various score data is also obtained using type-specific methods, e.g. restaurant reviews documents might have user supplied ratings, web pages have traffic and link-related metrics, music links often have play counts etc.
[0041] FIG. 2 is a schematic drawing of some key features of the system. After a search query is received by the query server 50 , it is separated into individual search enquiries 140 which will be sent to each search engine, e.g. news engine, songs engine etc. The query server also associates each individual query 140 with a mixing algorithm 150 and this information is passed to the mixers 120 . As described in more detail below, there may be a single mixer applying a mixing algorithm to all the results or there may be more than one mixer each applying the same or different mixing algorithm so that the results from one genre are not overrepresented in the overall list.
[0042] As shown in FIG. 1 , the normal components of a search engine are connected to a mixing engine 90 to generate the mixed list. The components of a simple mixing engine are shown in FIG. 3 a. When a search is performed, the query server performs a search within each type (news, songs and wikipedia as shown in FIG. 3 a ) and generates a (potentially long) list of candidate documents per type that match or are close to the query terms. The table below illustrates two different buckets of search results, namely news and songs:
[0000]
SONGS
NEWS
Scoring
Scoring (date based)
(based on no. plays)
1
Headline a
182000
1
Song a
3 million
2
Headline b
52000
2
Song b
20000
3
Headline c
33000
3
Song c
55
4
Headline d
15000
4
Song d
2
[0043] As shown above, each candidate document is assigned a type-specific score by combining its type-specific metrics using type-specific algorithms. These metrics include both static scoring data such as data obtained at crawl time and dynamic scoring data produced depending on the query terms and the words contained in the documents. For example, for news items, the scoring may be primarily based on date but may also be influenced by the popularity of the item.
[0044] The results from the multiple lists are each passed to a normalisation unit N 130 . The normalisation step is type-specific and involves scaling the type-specific score distribution into a generic score distribution such that document scores from different types can be reasonably compared against each other when sorting lists of documents of different types. The normalisation can be as simple as a linear scaling factor or a more complex algorithm that also modifies the distribution of scores within a standard range to better compare the relative rank of the Nth document of one type with Nth document of another type.
[0045] The normalised (or generic) scores for each type of document are passed to a mixer 120 to mix the results from the multiple lists. A combination of the generic scores and the position (rank) of each document within its type-specific list is used to rank the documents. The first step of this mixing (i.e. normalisation) is to enable inter-type score comparisons and the second step is to provide means to promote result diversity (i.e. promoting the likelihood of getting results of different types).
[0046] The combination of a generic score, g, with a type-specific result rank, r, can be any function f(g,r) provided that relative result ordering is maintained within each type, i.e. the condition is satisfied:
[0000] f ( g N , N )> f ( g M , M ) for any N<M
[0000] where g N is the generic score of the Nth highest-scoring document of type X and g M is the generic score of the Mth highest-scoring document of the same type X.
[0047] For example, the following function obviously rewards the generic score g and penalises high (i.e. bad) rank positions r:
[0000]
f
(
g
,
r
)
=
g
r
[0048] This is a very simple example and a real function might well be much more complex in shape. Suitable functions generally will reward a high value of g and penalise a high value of r.
[0049] A slightly more complex example involves making the combination function tunable. This may be convenient when tunability is a highly desirable feature in the development of a search engine using this arrangement of components. Thus, the function may be:
[0000]
f
(
g
,
r
)
=
ag
+
(
1
-
a
)
r
[0000] where a is a tuning factor with a=1 meaning no diversity, pure result rankings only and a=0 means pure diversity, one result from each category taken in sequence. Values of a between 0 and 1 are likely to represent a more sensible approach than either extreme.
[0050] FIG. 3 b shows the steps implemented by the mixing engine of FIG. 3 a. The query server receives the search query S 200 and sends it to each category search engine S 210 . Each search engine returns a list of results S 220 which are normalised S 230 and then mixed S 240 before outputting to a user.
[0051] FIG. 4 a shows a variation on the mixing engine of FIG. 3 a which incorporates trees of streams. In other words, various genre within one category are mixed before mixing with different categories. As shown in FIG. 4 a, the music category is subdivided into three genres, pop, classic and rock each having its own independent index. In this embodiment, the query passes via the main mixer 120 through the music mixer 140 so that a search is conducted over each separate music index. For each music genre, a list of candidate documents that match or are close to the query terms is generated together with a scoring of the relevancy of each document. The scoring for each genre is normalised and the normalised results are passed to the music mixer 170 for mixing. The results for each type of music are then mixed, as described above e.g. using the function described above and the tuning factor al, to generate an overall list of music results. Such a list may be considered to represent an interim combined list, and the various music lists may be considered to be selected lists.
[0052] Whilst the music results are being generated, the search query is also sent to a news index and a Wiki index (i.e. a collection of web pages e.g. Wikipedia), each generating a list of type specific results. No interim combined list is formed for the news and Wiki results and thus if the music lists are considered to be selected lists, the news and Wiki lists may be considered to be non-selected lists. The music, news and Wiki results are independently normalised using the appropriate technique by normalisation units 130 . The normalised results of each type are then mixed in mixer 120 , as described above e.g. using the function described above and the tuning factor a 2 , to yield a single list of results. In other words, the query server is arranged to form at least one interim list, namely for music and then to combine the results from the non-selected lists, e.g. for news and Wiki, with the results in the interim combined list. It will be appreciated that the tuning factor a 1 used for the initial music mixing may differ from the tuning factor a 2 used for the final mixing step. If the separate music categories were each mixed individually with news and wiki results, music may be overrepresented in the overall result list. However, by using two mixing steps, any lumpiness in the overall list may be reduced, e.g. by defining the mixing algorithms so that if two songs are adjacently listed in the results, the next result is from a different category.
[0053] It will be appreciated that the tuning parameters (a 1 , a 2 ) could be varied in real-time. This variation may be dependent for example on the search term that has been entered, or on the quality of the results from the various type-specific search engines. In this way, the balance of diversity versus type-specific score may be adapted depending on how applicable that diversity is.
[0054] FIG. 4 b shows the steps implemented by the mixing engine of FIG. 4 a. The query server receives the search query S 300 and sends it to each category search engine S 310 . Each search engine returns a list of results S 320 which are normalised S 330 . The normalised results from the music category and then mixed S 340 to generate a music results list. This music list is then mixed with the results from the other categories S 350 to generate an overall list before outputting to a user S 360 . As it will be appreciated, the mixing of the results from a particular category (i.e. a pre-mixing step) may apply to multiple categories before an overall mixing step is completed.
[0055] In all embodiments, each item in the results list is a single search result. The representation of a search result may be the content items main title, a summary description and other optional meta data such as links to the source site, links to related items, links to re-perform the search which produced the item and so on. Each result row in the list may also includes an image, a title, a description and a link to the online content which the result is representing.
[0056] It is primarily the intention that the tuning parameters of the relevant functions are useful for system administrators only. However, it is conceivable that a service might wish to use the above method to expose some factors as configurable user preferences.
[0057] The query server may provide for user login. The user is identified by registering a username and password and then subsequently by logging in with the same username and password. The registration process is a one-time process per user. In a preferred embodiment, the login process is also a one-time process per user by caching their credentials (or a unique key representing their identity) in a cookie. However, where cookies are not supported then the user is required to provide username and password for each use. The user could be required to login at the first page of the mobile search service or a later stage. Once a user has logged in, the user may be able to manually adjust the tuning factor to be used for mixing. Thus, the query server may be arranged to prompt a user to adjust the tuning factor. Alternatively, the system may automatically adjust the tuning factor to suit a particular user and such adjustment may be done in real-time.
[0058] As described above, wikipedia results are included in the overall results list. Wikipedia or other similar databases may also be used to help refine the search. For example, before sending the search query out to each category search engine, the query server may check on Wikipedia for the various meanings or interpretations for a particular search term. These results may be used to bias the search results, e.g. by biasing for particular categories which include the most likely meaning of the search term used. The tuning factor may thus be adjusted in real-time to achieve this biasing.
[0059] In all of the above embodiments, a mobile device may be any kind of mobile computing device, including laptop and hand held computers, portable music players, portable multimedia players, mobile phones. Users can use mobile devices such as phone-like handsets communicating over a wireless network, or any kind of wirelessly-connected mobile devices including PDAs, notepads, point-of-sale terminals, laptops etc. Each device typically comprises one or more CPUs, memory, I/O devices such as keypad, keyboard, microphone, touchscreen, a display and a wireless network radio interface.
[0060] These devices can typically run web browsers or microbrowser applications e.g. Openwave™, Access™, Opera™ Mozilla™ browsers, which can access web pages across the Internet. These may be normal HTML web pages, or they may be pages formatted specifically for mobile devices using various subsets and variants of HTML, including cHTML, WML, DHTML, XHTML, XHTML Basic and XHTML Mobile Profile. The browsers allow the users to click on hyperlinks within web pages which contain URLs (uniform resource locators) which direct the browser to retrieve a new web page.
[0061] The Web server can be a PC type computer or other conventional type capable of running any HTTP (Hyper-Text-Transfer-Protocol) compatible server software as is widely available. The Web server has a connection to the Internet 30 . These systems can be implemented on a wide variety of hardware and software platforms.
[0062] The summary page or package of screenviews which may be created as described in US 2007/00278329, US 2007/0067305 or US2007/0208704 can be implemented as a set of pages in XHTML Mobile Profile for example. As indicated by the W3C website, XHTML Mobile Profile is one in a series of XHTML specifications. The XHTML Mobile Profile document type includes the minimal set of modules required to be an XHTML Host Language document type, and in addition it includes images, forms, basic tables, and object support. It is designed for Web clients that do not support the full set of XHTML features; for example, Web clients such as mobile phones, PDAs, pagers, and settop boxes. The document type is rich enough for content authoring. XHTML Mobile Profile is designed as a common base that may be extended by additional modules from XHTML Modularization such as the Scripting Module. Thus it provides a common language supported by various kinds of user agents such as browsers. It is useful if the page format can be read and presented by many different versions of “legacy” browsers to maximize the user base among existing mobile telephone users for example.
[0063] The query server is typically connected to a database that stores detailed device profile information on mobile devices and desktop devices, including information on the device screen size, device capabilities and in particular the capabilities of the browser or microbrowser running on that device. The query server may be configured to detect the user agent identified in the HTTP headers contained in the request received from the mobile device's web browser. The server then adapts the package according to the model of mobile device.
[0064] The query server, and servers for indexing, calculating metrics and for crawling or metacrawling can be implemented using standard hardware. The hardware components of any server typically include: a central processing unit (CPU), an Input/Output (I/O) Controller, a system power and clock source; display driver; RAM; ROM; and a hard disk drive. A network interface provides connection to a computer network such as Ethernet, TCP/IP or other popular protocol network interfaces. The functionality may be embodied in software residing in computer-readable media (such as the hard drive, RAM, or ROM). A typical software hierarchy for the system can include a BIOS (Basic Input Output System) which is a set of low level computer hardware instructions, usually stored in ROM, for communications between an operating system, device driver(s) and hardware. Device drivers are hardware specific code used to communicate between the operating system and hardware peripherals. Applications are software applications written typically in C/C++, Java, assembler or equivalent which implement the desired functionality, running on top of and thus dependent on the operating system for interaction with other software code and hardware. The operating system loads after BIOS initializes, and controls and runs the hardware. Examples of operating systems include Linux™, Solaris™, Unix™, OSX™ Windows XP™ and equivalents.
[0065] Any of the additional features can be combined together and combined with any of the aspects. Other advantages will be apparent to those skilled in the art, especially over other prior art. No doubt many other effective alternatives will occur to the skilled person. It will be understood that the invention is not limited to the described embodiments and encompasses modifications apparent to those skilled in the art lying within the spirit and scope of the claims appended hereto. | At least some embodiments of this invention provide for a way to mix mobile content found as a result of searching and/or browsing on the Internet. Aspects of the invention provides software, systems (meaning software and hardware to run the software) or an exchange of signals with users to provide a mobile content service. Other related aspects provide methods for providing or using such a search service. According to one aspect there is provided a query server to provide a search service for searching computer accessible content, the query server being arranged to receive a search query from a user on a mobile device, output said search query to multiple sources of indexable information, input an individual list of results from each of said multiple sources together with a scoring for each result wherein each result has a position in its associated individual list determined by its scoring, combine said lists of results to form a single combined list wherein results in said single combined list are ranked using a combination of their scoring and position in their respective individual list and send said combined list of search results to a user's mobile device. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to beverage containers. More specifically, the present invention relates to a double-walled beverage container having inner and outer walls joined at an upper rim and having a thermal break formed between the walls.
[0003] 2. Related Art
[0004] Beverage containers exist in various shapes and sizes. One common type of beverage container is an aluminum can having a partially-removable tab and a finger lever for opening the tab. Once opened, a beverage can be consumed or poured through the opened tab. Various types of beverages, such as sodas, beer, etc., are contained in cans of this type.
[0005] Unfortunately, common aluminum beverage cans do not adequately insulate the contents of the can from heat outside of the can, due to the fact that the can is formed with a single wall which is thermally conductive. As a result, heat from the environment can heat the contents, and even more so, as one holds a cold beverage can, heat is transferred from one's hand to the contents of the can, adding sufficient heat to raise the temperature of the contents of the can to an undesirable level. One solution to this problem in the past is an insulating sleeve that fits over the can. Such sleeves are often made from foam or other similar insulating material. However such sleeves only partially fit over beverage containers, have poor insulating properties and are cumbersome to use. Other solutions relate to double-walled containers, however, these solutions do not provide a thermal break which extends, uninterrupted, along the entire side and bottom of the container.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a beverage container having a double-walled construction with a thermal break. The container includes an inner wall with an inner bottom wall for containing a beverage, an outer wall which extends about the inner wall, and an outer bottom wall which extends under the inner bottom wall. A thermal break extends, uninterrupted, between the inner wall and the outer wall and the inner bottom and outer bottom walls. The container includes a top having an upper rim which joins the periphery of the top, the inner wall, and the outer wall. The upper rim could be formed using a crimping process, wherein the peripheral edges of the top, the inner wall, and the outer wall are crimped together.
[0007] The outer wall and the thermal break are co-extensive in height with the inner wall, so as to completely surround the inner wall, and the thermal break extends, uninterrupted, between the inner and outer walls and between the inner and outer bottom walls. The thermal break inhibits heat from the environment from being transmitted into the contents of the can, and even more so, heat from a person's hand when holding the container, to keep a beverage within the container cool. The thermal break could comprise air and/or a material which occupies all or part of the space between inner and outer walls (e.g., in the form of vertical strips of material, or annular rings of material), or the thermal break could be entirely comprised of a thermally non-conductive material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing features of the invention will be apparent from the following Detailed Description of the Invention, taken in connection with the accompanying drawings, in which:
[0009] FIGS. 1A-1B are side and top views, respectively, showing the beverage container of the present invention;
[0010] FIG. 2 is a cross-sectional view of the beverage container of the present invention, taken along line 2 - 2 of FIG. 1B ;
[0011] FIGS. 3-5 are cross-sectional views of the beverage container of the present invention, showing various configurations of the thermal break;
[0012] FIGS. 6A-8 are close-up, cross-sectional views showing steps for fabricating the beverage container of the present invention; and
[0013] FIGS. 9-10 are partial perspective views showing various configurations of the spacers of the beverage container of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention relates to a beverage container, described in detail below in connection with FIGS. 1A-10 .
[0015] FIGS. 1A-1B are side and top views, respectively, of the beverage container 10 of the present invention. The container 10 includes an outer wall 12 having an outer bottom wall 12 b, and an inner wall 14 having an inner bottom wall 14 b positioned within the outer wall 12 and the outer bottom wall 12 b for containing a liquid (e.g., a beverage). A thermal break 16 extends uninterrupted between the inner surface of the outer wall 12 and the outer surface of the inner wall 14 , and between the inner surface of the outer bottom wall 12 b and the outer surface of the inner bottom wall 14 b. The inner surface of the outer wall 12 and the thermal break 16 are co-extensive in height with the outer surface of the inner wall 14 , so as to completely surround the outer surface of the inner wall 14 to provide a thermal break along the entire height of the container. The thermal break 16 inhibits thermal energy outside of the outer wall 12 and the outer bottom wall 12 b (e.g., heat in the ambient air, or heat from a person's hand when the container 10 is held) from being transmitted into a liquid contained within the inner wall 14 and the inner bottom wall 14 b, to assist in keeping a beverage cool. The thermal break 16 could comprise air and/or a material which occupies all or part of the space between inner and outer walls 12 , 14 and inner and outer bottom walls 12 b, 14 b (e.g., in the form of vertical strips of material, or annular rings of material, discussed below), or the thermal break could be entirely comprised of thermally non-conductive material.
[0016] As shown in FIGS. 1A-1B , the container 10 is in the shape of a conventional beverage container (e.g., the shape of a beverage can). Of course, this shape could be varied as desired. The container 10 includes a tapered upper region 18 , an upper rim 20 , a tapered lower region 22 , and a recessed bottom region 24 . A tab 26 and an associated finger lever 28 could be provided, as in conventional beverage cans. The finger lever 28 can be raised by a person's finger to apply force to the tab 26 to partially separate the tab 26 from a top 30 of the can and to force the tab 26 below the top 30 , so as to open the container 10 to provide access to a liquid contained within the inner wall 14 and the bottom inner wall 14 b. Advantageously, the thermal break 16 extends along the entire height of the container 10 , up to the upper rim 20 , and along the entire width of the bottom of the container 10 (i.e., extending continuously between the outer bottom wall 12 b and the inner bottom wall 14 b ) so as to maximize insulation of the outer wall 12 from the inner wall 14 . Indeed, physical contact between the outer wall 12 and the inner wall 14 only occurs only at the upper rim 20 , thereby minimizing conduction of thermal energy between the outer wall 12 and the inner wall 14 . It is noted that the outer wall 12 and the outer bottom wall 12 b, the inner wall 14 and the inner bottom wall 14 b, and the top 30 , as well as the tab 26 and the finger lever 28 , could be formed from any suitable, lightweight material, such as aluminum (as is used to form conventional beverage cans).
[0017] FIG. 2 is a cross-sectional view of the container 10 of the present invention, taken along the line 2 - 2 of FIG. 1B . The thermal break 16 could include annular strips of material 32 positioned between the outer wall 12 and the inner wall 14 . The strips 32 could be attached to the inner surface of the outer wall 12 and the outer surface of the inner wall 14 to provide a degree of structural rigidity for the container 10 and to resist compression of the outer wall 12 against the inner wall 14 (e.g., when force is applied by a person's hand while handling the container 10 ). Also, the strips 32 could be formed (e.g., by coating) on either the inner surface of the outer wall 12 or the outer surface of the inner wall 14 prior to assembly of the container 10 , or prior to the formation of the walls. The strips 32 also function as a thermal break. The strips 32 could be formed of any suitable, lightweight material, such as plastic or foam.
[0018] FIGS. 3-4 are cross-sectional views of the container 10 of the present invention, wherein the thermal break 16 includes a plurality of vertical strips 34 are positioned between the inner surface of the outer wall 12 and the outer surface of the inner wall 14 . Similar to the annular strips 32 shown in FIG. 2 , the vertical strips 34 could be attached between the inner surface of the outer wall 12 and the outer surface of the inner wall 14 to provide a degree of structural rigidity for the container 10 , and to resist compression of the outer wall 12 against the inner wall 14 . Additionally, similar to the annular strips 32 , the vertical strips 34 also function as a thermal break, and could be formed (e.g., by dipping, coating, spraying, etc.) on the inner surface of the outer wall 12 or the outer surface of the inner wall 14 prior to assembly of the container 10 , or prior to the formation of the walls. The strips 34 could be formed from any suitable, lightweight material, such as plastic or foam.
[0019] FIG. 5 is a cross-sectional view of the container 10 of the present invention, wherein a continuous, uninterrupted layer of thermally non-conductive material 36 forms the thermal break between the outer wall 12 and the inner wall 14 , and between the outer bottom wall 12 b and the inner bottom wall 14 b, of the container 10 . The layer 36 could be formed from any suitable, thermally non-conductive material, such as plastic, foam, etc., and provides added structural rigidity for the container 10 . The layer 36 could be formed on the outer surfaces of the inner wall 14 and the inner bottom wall 14 b, or on the inner surfaces of the outer wall 12 and the outer bottom wall 12 b, using an suitable process, such as dipping, coating, spraying, etc.
[0020] FIGS. 6A-8 are close-up, cross-sectional views showing fabrication of the container of the present invention. One way of fabricating the container is shown in FIGS. 6A-6B . First, the inner wall 14 , the outer wall 12 , and the top 30 are formed using conventional fabrication processes for forming components of aluminum cans. Then, as shown in FIG. 6A , the inner wall 14 is positioned within the outer wall 12 , and a flange 40 created on the inner wall 14 extends over the upper end 38 of the outer wall 12 and serves to support and locate the inner wall 14 with respect to the outer wall 12 and the inner bottom wall 14 b with respect to the outer bottom wall 12 b, so that a thermal break extending along the sides and bottom of the container is provided. Also, the top 30 is positioned on the flange 40 , such that a flange 42 of the top 30 is nested on top of the flange 40 of the inner wall 14 . Then, as shown in FIG. 6B , the flanges 40 , 42 and end 38 are crimped inwardly or seamed to form the upper rim 20 . It is noted that other methods of attaching the top 30 and the inner and outer walls 12 , 14 as may be known in the art are within the scope of the present invention. It is noted that if the strips of the present invention are used, or if the thermal break will be filled with material, the strips of material could be positioned between the outer surface of the inner wall 14 and inner surface of the outer wall 12 , or formed on either the outer surface of the inner wall 14 or the inner surface of the outer wall 12 (e.g., by coating, spraying, adhering, or otherwise applying) prior to formation of the inner and outer walls, or after formation of the walls prior to positioning the inner wall within the outer wall.
[0021] Another way of fabricating the beverage container of the present invention is shown in FIGS. 7A-7D . First, as shown in FIG. 7A , the layer 36 could be formed on the outer surface of the inner wall 14 (e.g., by coating, dipping, spraying, etc.). Optionally, a gap 37 could be provided to facilitate joining (e.g., crimping or seaming) of the inner wall 14 , the outer wall 12 , and the top 30 . Of course, the layer 36 could extend entirely along the inner wall 14 with no gap. Also, the layer 36 could be formed on the inner surface of the outer wall 12 , if desired. Once the layer 36 is formed, the inner wall 14 is inserted into position within the outer wall 12 , in the general direction indicated by arrow A, such that the inner wall 14 rests within the outer wall 12 , as shown in FIG. 7B . In such circumstances, the layer 36 serves to support and position the inner wall 14 with respect to the outer wall 12 . Then, as shown in FIG. 7C , the taper 18 is formed by bending both the inner wall 12 and the outer wall 14 , using conventional techniques utilized to form the taper of existing beverage containers. Finally, as shown in FIG. 7D , the top 7 D is positioned on the inner wall 14 and the outer wall 12 , and the flanges 40 , 42 and the end 38 are joined together (e.g., crimped, seamed, etc.) to form the complete container. As can be seen, the layer 36 extends up to the top 30 .
[0022] Yet another way of fabricating the beverage container of the present invention is shown in FIG. 8 . First, a taper 18 A is formed in the inner wall 14 , using conventional techniques. Then, the layer 36 is formed on the outer surface of the inner wall 14 (e.g., by dipping, coating, spraying, etc.), and the inner wall 14 is inserted into position within the outer wall 12 . As mentioned above, the layer 36 could also be formed on the inner surface of the outer wall 12 . Once the inner wall 14 is in position within the outer wall 12 , a taper could then be formed in the outer wall 12 to match the taper 18 a of the inner wall 14 , so that both walls 12 , 14 are tapered (as shown in FIG. 7C ). Then, as shown in FIG. 7D , the top 30 and walls 12 , 14 could be joined, to form the complete container.
[0023] It is noted that any desired number of strips, in any desired spatial arrangement, could form part of the thermal break 16 of the container 10 . For example, as shown in FIG. 9 , three vertical strips 34 could be included in the thermal break 16 between the inner surface of the outer wall 12 and the outer surface of the inner wall 14 . Also, as shown in FIG. 10 , three annular strips 32 could be included in the thermal break 16 between the inner surface of the outer wall 12 and the outer surface of the inner wall 14 .
[0024] Having thus described the invention in detail, it is to be understood that the foregoing description is not intended to limit the spirit or scope thereof What is desired to be protected is set forth in the following claims. | A beverage container having a double-walled construction is provided. The container includes an inner wall with an inner bottom wall for containing a beverage, an outer wall which extends about the inner wall, and an outer bottom wall which extends under the inner bottom wall. A thermal break extends uninterrupted between the outer surface of the inner wall and the inner surface of the outer wall and the inner bottom and outer bottom walls. The container includes a top having an upper rim which joins the periphery of the top, the inner wall, and the outer wall. | 1 |
DESCRIPTION OF THE INVENTION
The present invention relates to a polycarbonate/ABS blend compositions having improved impact resistance. The present compositions comprise a combination of polycarbonate, ABS resin and heat stabilizer.
In recent years, heat stability and impact resistance were required in molding thermoplastic resins which have certain special uses. Under these circumstances, general purpose grade plastics and ABS resins are unable to satisfy these performance requirements. Instead, expensive heat stable engineering plastics such as polycarbonate (PC), polysulfone (PSF) and polyphenylene oxide (PPO) were developed to solve these problems. These high performance resins are not only expensive, but also are difficult to process. In order to improve processing and heat resistance, the simplest way is to use polymer blending techniques, for example, PC/ABS polyblends exhibit very balanced mechanical properties and processability. These polyblending techniques have been described, for example, in Japan Patent Application 38-15225, 39-71, and 42-11496.
However, there are unstable quality conditions during blending of PC/ABS resins. The causes of this unstability were believed to be associated with residual impurities present in common preparation procedures for forming ABS. These impurities include emulsifiers, migrating agent, and suspension stabilizer. These trace impurities influnce PC in such a way that, during the melt blending of PC and ABS under elevated temperature, PC resin might be degraded due to heat decomposition. The heat degradation can lead to lower physical properties and darken color. Furthermore, the degree of degradation in blending of PC/ABS is more severe than that in molding of PC alone. In order to overcome these drawbacks, Japan Patent 56-131657 described use of organic and inorganic acids as heat stabilizers of PC/ABS polyblends, while U.S. Pat. No. 4,472,554 disclosed high molecular acids as heat stabilizer of PC/ABS polyblend.
Thus, the instant invention provides four types of compounds as heat stabilizers of PC/ABS polyblends:
(1) benzothiazole compounds;
(2) benzimidazole compounds;
(3) hydrazine compounds;
(4) cation exchange materials.
suitable polycarbonates for use in the present invention include those selected from aromatic polycarbonate, aliphatic polycarbonate, aliphatic-aromatic polycarbonate or halogen-substituted bisphenol-A polycarbonates.
Suitable ABS resins for use in the present invention include those selected from resins prepared by emulsion, suspension or solution polymerizations of cyanovinyl compounds, for example, acrylonitrile, conjugated dienes compounds, for example, butadiene, and aromatic-vinyl compounds, for example, styrene; or the polyblend prepared by melt blending of the above prepared resins with cyanovinyl-aromatic vinyl copolymer, for example, ABS/acrylonitrile-styrene copolymer blend.
The benzothiazole compounds suitable for use in the instant invention are compounds of general formula (I) ##STR4## where R is selected from hydrogen, alkyl, aryl or benzothiazolyl.
The benzimidazole compounds suitable for use as heat stabilizer in the instant invention include compounds of general formula (II) ##STR5## where R is selected from hydrogen, alkyl, aryl or benzimidazolyl.
Suitable hydrazine compounds for use as heat stabilizer in the instant invention include compounds of general formula (III) ##STR6## where R 1 and R 2 are independently selected from alkyl, aryl or alkyl- or aryl-substituted aryl.
The cation exchange material suitable for use as heat stabilizer in the instant invention comprise various cation salts of silicaluminates, where cations may be sodium, potassium, lithium, calcium, strotium or barium; zeolites having various mole number of crystalline water; metal salts of tripolyphosphate, where the metal ions may be sodium, potassium, calcium, strontium, or barium; or other cation exchange resins.
The amount of the above described heat stabilizer in the instant invention is in the range in the 0.01 to 5 phr (part per hundred part) based on the total weight of the PC/ABs polyblend.
The improvement of impact resistance of the polycarbonate polyblend through incorporation of the heat stabilizers of the present invention can be illustrated by the following examples, which are not meant to limit the instant invention. Data and figures in the tables are based on weight units unless stated otherwise.
EXAMPLES
The methods used in comparative examples 1-3 and examples 1-24 involve the drying of ABS and PC resins, compounding the resins according to suitable ratio, blending in extruder (blending temperature 220°-250° C., screw speed at 150 rpm), pelletizing and drying. The resulting material is injection molded into test specimens specified by ASTM and subjected to impact resistant test in accordance with ASTM D-256.
Data in Table 1 shows the effect of two benzothiazole type heat stabilizers on the impact strength of PC/ABS polyblend composition. As can be seen, heat stabilizers were not used in the three comparative examples while the types and amount of heat stabilizers used in examples 1-6 were listed in the Table together with the compositions of PC/ABS polyblend. Where similar polymer compositions were used, the impact strengths obtained in examples 1-6 were significantly higher than those obtained in corresponding comparative example 1-3. The improvements of impact strength of PC/ABS polyblend can be ascribed to the interaction of benzothiazole compounds with the impurities in ABS, for example migrating agent, so as to inhibit the thermal decomposition of PC during high temperature blending.
TABLE 1__________________________________________________________________________The effect of benzothiazole type heat stabilizer onthe impact strength of PC/ABS polyblend compositions. Comparative examples Examples 1 2 3 1 2 3 4 5 6__________________________________________________________________________ABS 75 50 25 75 75 50 50 25 25PC 25 50 75 25 25 50 50 75 75heat *G--R, R = hydrogen -- -- -- 0.3 -- 0.5 -- 0.2 --stabi- G--R, R = G -- -- -- -- 0.7 -- 0.5 -- 1.0lizerImpact Strength, notched, 0.2 0.5 8.0 5.0 4.3 14.5 12.0 14.2 13.8ft-lb/in__________________________________________________________________________ *G = C.sub.6 H.sub.4 SNCS
Table 2 shows the effect of benzimidazole type heat stabilizers on the impact strength of PC/ABS polyblend compositions. The polymers used in comparative examples 1 to 3 do not include the said heat stabilizer. The types and amounts of heat stabilizers used in example 7-12 are shown together with polymer composition in each example. The impact strengths obtained were significantly enhanced, wherein, the impact strengths obtained in examples with PC composition 25%, 50% and 75% were increased to 25, 30 and 2 times, respectively.
TABLE 2__________________________________________________________________________The effect of benzimidazole type heat stabilizer onthe impact strengths of PC/ABS polyblend compositions. Comparative examples Examples 1 2 3 7 8 9 10 11 12__________________________________________________________________________ABS 75 50 25 75 75 50 50 25 25PC 25 50 75 25 25 50 50 75 75heat *D--R, R = hydrogen -- -- -- 0.1 -- 0.5 -- 1.0 --stabi- D--R, R = D -- -- -- -- 0.3 -- 0.5 -- 0.8lizerImpact Strength, notched, 0.2 0.5 8.0 5.5 5.1 15.1 15.5 13.6 14.0ft-lb/in__________________________________________________________________________ *D = C.sub.6 H.sub.4 NHNCS
Table 3 shows the effect of 2 hydrazine type heat stabilizers on the impact strengths of PC/ABS polyblend compositions. Similarly, the impact strength in example 13-18 which include heat stabilizer were significantly improved over comparative examples which did not include heat stabilizers.
TABLE 3__________________________________________________________________________The effect of hydrazine type heat stabilizers onthe impact strength of PC/ABS polyblend compositions. Comparative examples Examples 1 2 3 13 14 15 16 17 18__________________________________________________________________________ABS 75 50 25 75 75 50 50 25 25PC 25 50 75 25 25 50 50 75 75heat stabilizer*R.sub.1AR.sub.2, -- -- -- 0.8 -- 0.5 -- 0.1 -- ##STR7##R.sub.1AR.sub.2 -- -- -- -- 0.2 -- 0.5 -- 1.0R = C.sub.10 H.sub.20,R.sub.2 = phenylImpact Strength, notched, 0.2 0.5 8.0 4.1 4.6 14.9 13.5 13.1 13.4ft-lb/in__________________________________________________________________________ ##STR8##
Table 4 shows the effect of two types of cation exchange materials as the heat stabilizer on the impact strengths of PC/ABS polyblend compositions. The impact strengths obtained in example 19-24 which included with said heat stabilizers showed improved results as compared to the corresponding comparative examples 1-3.
TABLE 4__________________________________________________________________________The effect of cation exchange materials on the impact strengthsof PC/ABS polyblend compositions. Comparative examples Examples 1 2 3 19 20 21 22 23 24__________________________________________________________________________ABS 75 50 25 75 75 50 50 25 25PC 25 50 75 25 25 50 50 75 75heat Zeolite (NaX) -- -- -- 0.5 -- 0.5 -- 0.3 --stabi- Tripolyphosphate -- -- -- -- 0.9 -- 0.5 -- 0.7lizerImpact Strength, notched, 0.2 0.5 8.0 5.7 4.6 15.0 12.8 14.1 13.0ft-lb/in__________________________________________________________________________
The improved results of the use of the heat stabilizers of the present invention on the impact strength of PC/ABS polyblend compositions are clearly demonstrated by the forgoing examples. | A polycarbonate blend composition comprising 95-5 wt % of a polycarbonate resin, 5-95% of an ABS resin and 0-01-5 parts per hundred of a heat stabilizer (relative to the combined resin weight). The heat stabilizers are selected from benzothiazoles of formula: ##STR1## wherein R is selected from hydrogen, alkyl, aryl and benzothiazolyl; benzimidazole compounds of formula: ##STR2## wherein R is selected from hydrogen, alkyl, aryl and benzimidazolyl; hydrazine compound of formula: ##STR3## wherein R is alkyl, and cation exchange materials selected from metal salts of silicaluminate zeolites, metal salts of triphosphates and cation exchange resins. These poly blend composition display improved impact resistance. | 2 |
[0001] This application claims the benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application No. 60/722,347 filed Oct. 1, 2005. Such provisional application is hereby incorporated by reference in its entirety into this application.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a barrier in a residential home, particularly to such a barrier having a gate, and specifically to such a barrier having a first gate that in turn has a second gate.
BACKGROUND OF THE INVENTION
[0003] Homes are dangerous places for children. Children fall down stairs, stick forks into electrical sockets, climb onto countertops, put metal objects into microwaves, turn on gas stoves, operate electric hair dryers on wet floors, hide in freezers and front load washers and dryers, open medicine cabinets, and pester old dogs. New parents soon become safety conscious.
[0004] A staircase is especially dangerous. The staircase itself is enticing. It offers a place to slide down. Or, if an open staircase, it is a cliff off which to hang and drop. What is beyond the staircase is further fun. The staircase may lead to a dark basement. Or it may run to a strangely lit attic.
[0005] Some rooms can temporarily or permanently be off-limits to children. One such room is the kitchen. For example, the cook may not wish to watch where he or she is walking while carrying a hot dish in glass bakeware from the stove to a counter top.
[0006] To minimize some of the above problems, a child safety gate may help to keep a child out of a certain area. The child safety gate may be positioned at the top of a staircase or at the bottom of a staircase. The child safety gate may be positioned between the living room and the kitchen while dinner is prepared. Or the child safety gate may be positioned at some other location in the home.
[0007] One problem with the child safety gate is its very nature: it is a barrier. For example, even an adult has difficulty stepping high over the child safety gate, an activity that in itself can inflict serious bodily harm. To minimize such high stepping, many child safety gates have an easy open—but child proof—gate so that the older child or adult is minimally burdened by the barrier.
[0008] Moreover, those who cannot speak of their problems often suffer great inconveniences from a child safety gate. For example, small dogs cannot jump over or squeeze through the child safety gate like a cat. The small dog, therefore, must suffer from 1) lack of attention from a small child because the small dog cannot—because of the child safety gate—gain access to the child or 2) too much attention from a small child because the small dog cannot—because of the child safety gate—get away from the child.
SUMMARY OF THE INVENTION
[0009] A feature of the present invention is the provision in a removable barrier in a residential home having a relatively large gate, of a relatively small gate within the relatively large gate.
[0010] Another feature of the present invention is the provision in such a removable barrier, of the size of the relatively small gate being sufficiently great to permit the passage of a relatively small dog, and of the size of the relatively small gate being sufficiently small to prevent a toddler from climbing through the relatively small gate. Preferably, the relatively small gate measures about ten inches in height (from top to bottom) and about seven inches in width (from side to side).
[0011] Another feature of the present invention is the provision in such a removable barrier, of the relatively large gate swinging on an axis that is offset from the axis on which the relatively small gate swings.
[0012] Another feature of the present invention is the provision in such a removable barrier, of the relatively large gate swinging on an axis that is generally parallel to the axis on which the relatively small gate swings.
[0013] Another feature of the present invention is the provision in such a removable barrier, of each of the relatively large and small gates having lowermost portions, and of the lowermost portions confronting each other and being swingable relative to each other.
[0014] Another feature of the present invention is the provision in such a removable barrier, of the relatively large gate being swingable in one of a forward and rearward direction, and of the small gate being swingable in each of the forward and rearward directions.
[0015] An advantage of the present invention is that a small dog may be permitted to pass through the present residential home passageway barrier and, at the same time, a toddler is not permitted to pass through the child safety gate.
[0016] Another advantage of the present invention is that the present residential home passageway barrier is inexpensive to manufacture.
[0017] Another advantage of the present invention is that the present residential home passageway barrier is simple to set up in a passageway of a residential home.
[0018] Another advantage of the present invention is that the present residential home passageway barrier is simple to operate.
[0019] Another advantage of the present invention is that the present residential home passageway barrier is simple to take down from a passageway in a residential home.
[0020] Another advantage of the present invention is that the present residential home passageway barrier is see-through. The frame of the residential home passageway barrier is see through. The relatively large gate is see through. The relatively small gate is see through. The caretakers and children can see each other when on opposing sides of the barrier.
[0021] Another advantage of the present invention is that the present residential home passageway barrier is removable from the passageway of the residential home and portable such that the barrier can be set up at another location.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1A is a perspective view of the present residential passageway barrier set up in a passageway of a residential home, where the passageway is shown in phantom.
[0023] FIG. 1B shows a front partial view of the residential passageway barrier of FIG. 1A and further shows a front full view of an extension for the residential passageway barrier of FIG. 1A .
[0024] FIG. 2A is a front detail view of the lock mechanism of the residential passageway barrier of FIG. 1A , where the lock mechanism is in a closed position.
[0025] FIG. 2B is a front detail view of the lock mechanism of the residential passageway barrier of FIG. 1A , where the lock mechanism is in an open position.
[0026] FIG. 2C is a perspective detail view of the relatively small gate of the residential passageway barrier of FIG. 1A and shows the relatively small gate in an open position.
DESCRIPTION
[0027] As shown in FIG. 1A , the present residential home passageway barrier or child safety gate is indicated by reference numeral 10 . Barrier 10 generally includes a frame 12 , which includes a relatively large gate 14 , which includes a relatively small gate 16 . Barrier 10 can be set up in a passageway 18 of a residential home 20 . The passageway 18 includes opposing sides 22 , 24 . Passageway 18 can be a hallway or an entrance into a room or the space at the top of a staircase or the space at the bottom of a staircase or another type of passageway.
[0028] More specifically, frame 12 includes a generally U-shaped main frame portion 26 . Main frame portion 26 includes a lowermost tubular horizontally extending frame member 28 that runs from one side 22 of passageway 18 to the other side 24 of passageway 18 . At each of the ends of the lowermost frame member 28 , a threaded connection 30 is engaged. Threaded connection 30 can be screwed into or out of its respective end of lowermost frame section 28 to effectively lengthen or shorten the length of lowermost frame member 28 such that lowermost frame member 28 can be rigidly and removably engaged between opposing sides 22 and 24 of passageway 18 . Threaded connection 30 includes an elastomeric or plastic or resilient head 32 that engages without marking up the surfaces of sides 22 and 24 .
[0029] U-shaped main frame portion 26 further includes an upright support member 34 . Upright support member 34 is generally T-shaped so as to include an inwardly extending frame member 36 and an outwardly extending frame member 38 . Outwardly extending frame member 38 includes threaded connection 30 having head 32 .
[0030] U-shaped main frame portion 26 further includes upright support member 40 . Upright support member 40 is formed in the shape of an inverted L so as to include an outwardly extending frame member 42 that includes threaded connection 30 with head 32 . Outwardly extending frame member 42 is coaxial with outwardly extending frame member 38 . It should be noted that, when fabricated, U-shaped main frame portion 26 is formed such that upright support members 34 and 40 are slightly oblique relative to one another and are not parallel to one another, such that upright support member 40 lies at an obtuse (greater than ninety degrees) angle relative to lowermost frame member 28 , and such that pressure must be applied to upright support member 40 to draw upright support member 40 into a right angle relationship with lowermost frame member 28 . Such pressure is the screwing outwardly of threaded connections 30 of one or more of support members 38 and 42 . Such pressure and such a drawing in of upright support member 40 provides resiliency and rigidity to frame 12 as a whole. Such pressure and such a drawing in of upright support member 40 drawings the upper portion of upright support member to a locking relationship with locking mechanism 44 .
[0031] Lowermost frame member 28 and upright support members 34 and 40 are preferably one-piece. Each of lowermost frame member 28 , upright support member 34 , and upright support member 40 are rectangular in section and are tubular.
[0032] Frame 12 further includes an upright support member 46 rigidly engaged, such as by welding, between outwardly extending support member 38 and lowermost support member 28 . Frame 12 further includes a generally U-shaped support member 48 rigidly engaged at its ends, such as by welding, to upright support member 46 . Support member 48 confronts side 24 of passageway 18 .
[0033] Frame 12 further includes an upright support member 50 rigidly engaged, such as by welding, between outwardly extending support member 42 and lowermost support member 28 . Frame 12 further includes a generally U-shaped support member 52 rigidly engaged at its ends, such as by welding, to upright support member 50 . Support member 52 confronts side 22 of passageway 18 .
[0034] Relatively large gate 14 is swingably engaged via pin connectors between inwardly extending support member 36 and lowermost support member 28 . Relatively large gate 14 includes a main or exterior rectangular frame portion 54 that includes a lowermost horizontally extending support member 56 , an uppermost horizontally extending support member 58 , an end upright support member 60 that defines the axis on which relatively large gate 14 swings, and an end upright support member 62 . Each of the support members 56 , 58 , 60 and 62 are tubular and rectangular in section. Relatively large gate 14 further includes, within the rectangular frame portion 54 , an upright support member 64 extending to and between lowermost support member 56 and uppermost support member 58 , upright support member 66 extending to and between the lowermost support member 56 and uppermost support member 58 , and a horizontally extending support member 68 extending between the upright support members 64 and 66 . Relatively large gate 14 further includes upright support members 70 and 72 , where each of the upright support members 70 and 72 extends to and between horizontally extending support member 68 and uppermost support member 58 . Relatively large gate 14 further includes a rigid tab 73 or downward extension 73 of upright support member 62 that confronts a side surface of horizontally extending support member 28 . With rigid tab 73 , relatively large gate 14 is a one-way swingable gate that swings in only one of a forward or rearward direction, depending upon the orientation of the barrier 10 as a whole and the particular passageway 18 in which the barrier 10 is set up and is barred, via rigid tab 73 , from swinging in the other direction.
[0035] As shown in FIG. 2C , relatively small gate 16 is swingably engaged via pin connectors 74 between horizontally extending support member 68 and lowermost support member 56 . Relatively large gate 16 includes a main or exterior rectangular frame portion 76 that includes a lowermost horizontally extending support member 78 , an uppermost horizontally extending support member 80 , an end upright support member 82 that defines the axis on which relatively large gate 16 swings, and an end upright support member 84 . Relatively small gate 16 further includes upright support members 86 and 88 extending to and between lowermost support member 78 and uppermost support member 80 . Upright support member 86 is coaxial with upright support member 70 when the relatively small gate 16 is closed. Upright support member 88 is coaxial with upright support member 72 when the relatively small gate 16 is closed. Relatively small gate 16 further includes a coil spring loaded pin connector 90 , mounted in upright support member 84 , that can engage an opening 92 in upright support member 66 via a distal end 94 . Pin connector 90 further includes a roughened cap 96 that acts as a handle that fingers can manipulate to draw the biased pin connector end 94 out of the opening 92 . When cap 96 is released, pin connector end 94 is biased via the internal coil spring such that pin connector end 94 automatically is pushed away from upright support member 84 and into opening 92 if the relatively small gate 16 is aligned with or coplanar with relatively large gate 14 .
[0036] It should be noted that lowermost support member 56 of the relatively large gate 14 is slightly spaced, such as via a nylon or plastic washer, from lowermost support member 28 of main frame 26 such that the relatively large gate 14 is swingable. It should be noted that each of the support members 78 , 80 , 82 and 84 of the relatively small gate 16 is slightly spaced from its respective support members 56 , 68 , 64 and 66 of the relatively large gate 14 such that the relatively small gate 16 is swingable within the relatively large gate 14 .
[0037] As shown in FIGS. 2A and 2B , locking mechanism 44 includes a sliding foot 98 having a U-shaped distal end 100 for engaging upright support member 40 , which is rectangular in section, where the U-shape wraps about the upright front and back sides of the upright support member 40 . Foot 98 is engaged in and slides into and out of a body 102 of locking mechanism 44 . Body 102 is fixed, via pin connectors, to the relatively large gate 14 about support members 58 , 62 , and 66 . U-shaped distal end 100 is drawn away from and pushed back about upright support member 40 via a pivot arm 104 that is swingably fixed to body 102 via a pivot pin 106 . Pivot arm 104 includes a fixed raised portion 108 having a border 110 or edge 110 such that edge 110 and an edge 112 of pivot arm 104 are generally horizontally extending edges that aid a hand getting a grip to lift pivot arm 104 generally vertically to slide distal end 100 onto and off of upright support member 40 . Locking mechanism 44 further includes a lock 114 . Lock 114 includes a body 116 that is slidingly fixed on uppermost support member 58 via a pin 118 engaging a slot in uppermost support member 58 . Body 116 is internally spring loaded, such as via a coil spring, such that body 116 is biased to a normally closed and locked position where a rigid tab 120 or rigid extension 120 of body 116 confronts an end 122 of pivot arm 104 , as shown in FIG. 2A . Body 116 is slideable from the normally closed and locked position to an open position, as shown in FIG. 2 B, such that tab 120 is slid away from pivot arm end 122 such that pivot arm 104 can be pivoted up, an action that draws foot 98 into pivot arm body 102 , via an internal rider and track arrangement between the pivot arm 104 and the foot 98 .
[0038] As shown in FIG. 1B , barrier 10 may include a barrier extension 124 . Barrier extension 124 includes a lowermost support member 126 and an uppermost support member 128 . Barrier extension 124 further includes a pair of upright support members 130 and 132 engaged to and between the lowermost support member 126 and uppermost support member 128 . Barrier extension 124 further includes a generally U-shaped support member 134 rigidly engaged at its ends, such as by welding, to upright support member 132 . Support member 134 , when barrier extension 124 is engaged to barrier 10 , confronts one of the sides 22 , 24 of passageway 18 . Lowermost support member 126 includes a U-shaped connection 136 that engages, such as by a frictional engagement, an end 138 of lowermost support member 28 of frame 12 . Uppermost support member 128 includes a U-shaped connection 140 that engages, such as by a frictional engagement, an end 142 of outwardly extending frame member 38 . The friction fit between U-shaped connections 136 and 140 and respective ends 138 and 142 can be supplemented by an internal pin and hole arrangement, where the pins and holes extend horizontally and where the pin is fixed to one of frame 12 and barrier extension 124 and where the hole is formed in the other of the frame 12 and barrier extension 124 .
[0039] Threaded connection 30 is a removable connection that is screwable off frame 12 , such as off ends 138 and 142 . FIG. 1A shows the threaded connection 30 on each of the ends of lowermost support member 28 and on each of the outwardly extending frame sections 38 and 42 . FIG. 1B shows the threaded connection 30 off of ends 138 , 142 and screwed onto the outer ends of support members 126 and 128 . It should be noted that barrier extension 124 is engagable to either end of frame 12 such that barrier extension 124 can confront either support member 48 or support member 52 , that barrier extensions 124 can be utilized on both ends of the frame 12 , and that one barrier extension 124 can engage another barrier extension 124 that can engage still another barrier extension 124 and so on.
[0040] In operation, to install the barrier 10 , the width of the passageway 18 is measured so as to ascertain whether frame 12 will be used by itself or whether a barrier extension 124 will be required. If required, then one or more barrier extensions 124 are engaged. Then the threaded connections 30 having the heads 32 are screwed into the four corners of the barrier 10 . Then the barrier 10 is set between the sides 22 and 24 of the passageway 18 and then the threaded connections 30 are screwed outwardly so as to engage the sides 22 and 24 . When barrier 10 is in place, lowermost support member 28 may lie on the floor or be slightly spaced off the floor. As the threaded connections 30 are screwed out, upright support member 40 is drawn into engagement with the U-shaped distal end 100 of the lock mechanism 44 such that barrier 10 is placed under pressure and such that barrier 10 is secure in its location in the passageway 18 .
[0041] In operation, to open the relatively large gate 14 , the sliding lock 114 is operated to take tab 120 out of a confronting relationship with pivot arm end 122 . Then the pivot arm 104 is lifted to slide in foot 98 and draw U-shaped distal end 100 out of an engaged position with upright support member 40 . Then the relatively large gate 14 is swung open on an axis defined by upright support member 60 . Then the user can walk through the resultant opening of the barrier 10 . Once through, the user swings the relatively large gate 14 shut, slides open the lock 114 , lays down the pivot arm 104 fully onto the pivot arm body 102 , and releases the lock 114 , thus permitting the tab 120 to confront and lay over pivot arm end 122 .
[0042] In operation, to open the relatively large gate 14 without repeatedly using lock 114 , lock 114 is slid away from pivot arm end 122 , which is then lifted up slightly, whereupon lock 114 is released to permit tab 120 to slide under pivot arm end 122 such that pivot arm end 122 lies on top of tab 120 . Then, when a user approaches barrier 10 , the user merely lifts up pivot arm 104 to open the gate 14 , and then merely pushes pivot arm 104 back down to close gate 14 such that the user need not slide lock 114 back and forth. This arrangement may be used, for example, when children are not yet sufficiently tall to reach the pivot arm 104 .
[0043] In operation, to open the relatively small gate 16 , the cap or handle end 96 is drawn out so as to bring the distal pin end 94 out of opening 92 , whereupon the relatively small gate 16 can be swung open about an axis defined by upright support member 82 . Relatively small gate 16 can open to and away from either face of the barrier 10 such that the small gate 16 can open forwardly or rearwardly. When the relatively small gate 16 is open and the connector pin 90 is released, the connector pin 90 is biased such that distal pin end 94 juts out from upright support member 84 and such that distal pin end 94 abuts and make contacts with upright support member 66 as the relatively small gate 16 is swung back to the relatively large gate 14 . Thus, relatively small gate 16 can remain open if desired for a small dog to push open with his or her nose or draw back with his or her paw. To close relatively small gate 16 , pin 90 is drawn in until the distal end 94 can move past upright support member 66 and into the opening 92 of upright support member 66 .
[0044] In operation, when the relatively small gate 16 is open, the opening left by the small gate 16 is sufficiently large such that a small dog can walk through and is sufficiently small such that a toddler cannot crawl through.
[0045] In operation, to uninstall the barrier 10 , one or more threaded connections 30 are screwed into the frame 12 so as to release pressure in frame 12 , and then threaded connections 30 are screwed in (such as one pair of threaded connections engaging side 22 ) to fully release the barrier 10 from the passageway 18 . The barrier 10 can then be carried away and set up at another location or stored.
[0046] Relatively large gate 14 swings on an axis defined by upright support member 60 . Relatively small gate 16 swings on an axis defined by upright support member 82 . Such axis and upright support members 60 and 82 are parallel to and offset from each other.
[0047] U-shaped main frame portion 26 includes a first rigid portion, such as upright support member 34 , and a second rigid portion, such as upright support member 40 . The relatively large gate 14 is swingably engaged to one such rigid portion and lockable to the other such rigid portion.
[0048] Relatively large gate 14 has lowermost support member 56 that confronts and swings relative to lowermost support member 78 of the relatively small gate 16 .
[0049] Relatively large gate 14 is in a plane defined by frame 12 when gate 14 is closed. Relatively small gate 16 is in a plane defined by relatively large gate 14 when small gate 16 is closed such that the frame, large gate 14 and small gate 16 are coplanar when the gates 14 and 16 are closed.
[0050] Tab 73 can be on either of the large gate 14 or on frame portions of the support members confronting upright support member 62 , such as support member 28 such that one of the gate 14 or frame portion can block the other of the gate 14 or frame portion such that gate 14 is a one-way swingable gate.
[0051] Relatively small gate 16 can be swung either way through the plane defined by relatively large gate 16 .
[0052] It should be noted that relatively large gate 14 and relatively small gate 16 are independent of the other. Operation of one gate is not dependent upon operation of the other gate.
[0053] The relatively large gate 14 includes a proximal end frame member, such as upright support member 60 , and a distal end frame member, such as upright support member 62 . The relatively small gate 16 includes a proximal end frame member, such as upright support member 82 , and a distal end frame member, such as upright support member 84 . Such proximal end frame members are spaced from each other. Such distal end frame members are spaced from each other.
[0054] Relatively large gate 14 includes a plurality of upright support members. Relatively small gate 16 includes a plurality of upright support members. The upright support members 86 and 88 of the relatively small gate 16 are coaxial with respective support members 70 and 72 of the relatively large gate 14 .
[0055] One rigid portion of frame 12 includes upright support members 30 , 46 and 48 and runs on one side of the relatively large gate 14 . Another rigid portion of frame 12 includes upright support members 40 , 50 and 52 and runs on the other side of the relatively large gate 14 .
[0056] The height of barrier 10 (and the height of relatively large gate 14 ) is preferably between about two feet and about five feet, more preferably between about two and one-half feet and about three and one-half feet, and most preferably between about three feet and about four feet.
[0057] The height (from top to bottom) of an opening left by the open small gate 16 is preferably between about eight and twelve inches, more preferably between about nine and eleven inches, and most preferably about ten inches. The width (from side to side) of an opening left by the open small gate 16 is preferably between about five and nine inches, more preferably between about six and eight inches, and most preferably about seven inches.
[0058] According to the American Heritage® Dictionary of the English Language, Fourth Edition, Copyright© 2000, a gate is a structure that can be swung, drawn, or lowered to block an entrance or a passageway.
[0059] An example of a gate that can be drawn is a scissors like gate that is drawn shut or opened up accordion style. Another example of a gate that can be drawn shut or drawn open is a sliding gate.
[0060] An example of a gate that can be lowered or raised is a sliding gate. Another example of a gate that can be lowered is a scissors like gate that is lowered or raised accordion style. Still another example of a gate that can be lowered or raised is a gate swinging on a horizontal axis.
[0061] Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalents of the claims are intended to be embraced therein. | A gate within a gate within a barrier. A first, relatively small gate is engaged within a second, relatively large gate, which is engaged in a barrier for extending across a passageway of a residence. The relatively large gate can be closed to, for example, minimize access of toddlers to the passageway, while the relatively small gate can be opened to, for example, maximize access of small dogs to the passageway. One example of a passageway is the head or bottom of a stairway. The relatively large gate, when closed, minimizes toddlers from falling down or climbing up stairs. The relatively small gate, when open, permits small dogs to walk down or climb up the stairs. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Application Ser. No. 61/899,409, filed Nov. 4, 2013 (pending), the disclosure of which is hereby incorporated by reference herein.
TECHNICAL FIELD
[0002] The present invention relates generally to microwave-excited ultraviolet lamp systems and methods.
BACKGROUND
[0003] Ultraviolet lamp systems or lamp heads are used in many applications. For example, systems may be used for heating or curing of adhesives, sealants, inks or other coatings or for other purposes such as surface treatments. These systems typically couple microwave energy to an electrodeless lamp, such as an ultraviolet (UV) plasma lamp bulb mounted within a microwave chamber of the lamp system. In many ultraviolet lamp systems, one or more magnetrons are provided in the lamp head housing to direct microwave radiation to the plasma lamp bulb within the microwave chamber. The magnetrons are coupled to the microwave chamber through waveguides that include output ports connected to an upper end of the chamber. When the plasma lamp bulb is sufficiently excited by the microwave energy, it emits ultraviolet radiation through an open lamp face of the lamp system to irradiate a substrate which is positioned at an optimal distance from the open lamp face.
[0004] A source of forced air is fluidly connected to a housing of the lamp system which contains the magnetrons, the microwave chamber and the plasma lamp bulb. The source of forced air is operable to direct cooling air, such as 350 CFM of cooling air for example, through the housing and into the microwave chamber to cool the magnetrons and the plasma lamp bulb during irradiation of the substrate by the lamp system.
[0005] In some UV heating and curing applications, the lamp system includes a mesh screen mounted at the open lamp face. The screen is transmissive to ultraviolet radiation but is opaque to microwaves. The configuration of the mesh screen also permits the significant airflow of cooling air to pass therethrough and toward the substrate.
[0006] In other applications, the substrates irradiated by the UV lamp may be rather wide and require multiple lamp heads to be mounted adjacent one another across the width of the substrate. The substrate is then moved relative to the lamp heads in order to irradiate the entire surface of the substrate that is facing the lamp heads. For example, these substrates may comprise large, flat panels used for flat screen televisions, or films such as those used for tinting windows. In such cases, it is important to provide uniform exposure of ultraviolet radiation across the full width of the substrate. A problem that has developed involves the occurrence of “striping” in which thin bands or stripes of underexposed substrate areas occur generally between the adjacent lamp heads.
[0007] Therefore, it would be desirable to provide continued improvements in this area to provide more effective cooling within a lamp head housing, and to provide more uniform ultraviolet irradiation to wide substrates when using multiple, adjacently mounted lamp heads.
[0008] These and other features of the various embodiments of this invention will become more readily apparent to those of ordinary skill upon review of the following detailed description of the illustrated embodiments taken in conjunction with the accompanying drawings.
SUMMARY
[0009] In an illustrative embodiment the invention provides an apparatus for generating ultraviolet light for irradiating a substrate. The apparatus includes a housing enclosing an interior space. The housing includes an inlet for receiving a cooling air flow, and a window configured to emit ultraviolet light and discharge the cooling air flow. A lamp bulb is mounted within the interior space between the inlet and the window. First and second microwave generators are respectively mounted between the inlet and the lamp bulb. A plate structure is positioned between the inlet and the first and second microwave generators. The plate structure at least partially defines a plenum within the housing and includes first and second openings generally aligned with the respective first and second microwave generators to direct first and second portions of the cooling air flow at the first and second microwave generators. The plate structure may comprise more than one plate, or may be constructed from multiple, distinct plates. The housing further comprises a top side and a rear side. The inlet is located in the top side, and the plate structure extends from the top side to the rear side. The plate structure includes a section oriented at an acute angle relative to vertical between the top side and the rear side.
[0010] The invention further provides a method of irradiating a substrate with ultraviolet light from at least first and second apparatus. Each apparatus includes a housing holding an ultraviolet lamp bulb and including a window. The method comprises mounting the first and second apparatus adjacent to one another with the ultraviolet lamp bulbs extending generally parallel to each other along their respective lengths. The substrate is positioned at an optimal distance from the windows of the first and second apparatus. The first and second apparatus and the substrate are moved relative to one another in a direction perpendicular to the respective lengths of the ultraviolet lamp bulbs. While moving the first and second apparatus and the substrate relative to one another, ultraviolet light is emitted from each apparatus through the respective windows such that adjacent patterns of ultraviolet light are directed onto the substrate. The patterns emitted from the adjacent apparatus meet on the substrate to prevent underexposed areas along the substrate at the locations generally between the adjacent first and second apparatus. Mounting the first and second apparatus further comprises mounting the first and second apparatus in abutting, contacting relationship to one another. Mounting the first and second apparatus also further comprises orienting the ultraviolet lamp bulbs to extend coaxial relative to each other along their respective lengths.
[0011] Various additional features and advantages of the invention will become more apparent to those of ordinary skill in the art upon review of the following detailed description of the illustrative embodiments taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross sectional view of an apparatus for irradiating substrates with ultraviolet light, constructed in accordance with the prior art.
[0013] FIG. 2 is a perspective view a portion of a housing associated with an apparatus for irradiating substrates with ultraviolet light, and constructed in accordance with an illustrative embodiment of the invention.
[0014] FIG. 3 is a perspective view of the plate structure forming the plenum of the housing shown in FIG. 2 .
[0015] FIG. 4 is a cross sectional view of an apparatus for irradiating substrates with ultraviolet light, and constructed in accordance with an illustrative embodiment of the invention.
[0016] FIG. 5 is an enlarged portion of the cross sectional view shown in FIG. 4 , and illustrating the lower section of the apparatus irradiating a substrate with ultraviolet light.
[0017] FIG. 6 is a cross sectional view taken along line 6 - 6 of FIG. 1 .
[0018] FIG. 7 is a cross sectional view taken along line 7 - 7 of FIG. 5 .
[0019] FIG. 8 is a cross sectional view showing two apparatus of the prior art placed side-by-side in abutting relation and irradiating a substrate with ultraviolet light.
[0020] FIG. 8A is a top view schematically illustrating the resulting substrate and the “striping” effect generally formed on the substrate in an area of the substrate between the two apparatus.
[0021] FIG. 9 is a cross sectional view showing two apparatus of the invention placed side-by-side in abutting relation and irradiating a substrate with ultraviolet light.
[0022] FIG. 9A is a top view schematically illustrating the resulting uniformly irradiated substrate with no “striping” effect.
DETAILED DESCRIPTION
[0023] FIG. 1 illustrates a microwave excited ultraviolet lamp system or apparatus 10 constructed in accordance with the prior art. Specifically, apparatus 10 includes a housing 12 containing a pair of microwave generators, illustrated as a pair of magnetrons 14 (only one shown) that are each coupled to a longitudinally extending microwave chamber 16 . An electrodeless plasma lamp 22 , in the form of a sealed, longitudinally extending plasma lamp bulb, is mounted within the microwave chamber 16 and supported adjacent the upper end of the chamber 16 . Housing 12 includes an inlet 12 a on a top side 12 b connected in fluid communication with a source of pressurized air for purposes of accepting a cooling air flow within the housing 12 . A plenum 24 is located at an upper end of the housing 12 , while a lower end of the housing 12 forms a lamp head 28 . The source of pressurized air directs a cooling air flow, represented diagrammatically by arrows 30 , through the plenum 24 and at the magnetrons 14 , as well as the lamp bulb 22 . The plenum 24 is formed by a plate structure 40 having a single opening 42 for directing the air at the pair of magnetrons 14 . The plate structure 40 extends from the top side 12 b of the housing 12 to a rear side 12 c of the housing 12 . Ultraviolet light from the bulb 22 is emitted through an open face or window 50 .
[0024] Now referring to FIGS. 2-4 , an apparatus 10 ′ constructed in accordance with various aspects or embodiments of the present invention is shown. In these figures, like structure is indicated by like reference numerals and, therefore, additional explanation of such structure is unnecessary. Corresponding elements that have been changed in design are indicated with the same numerals as in FIG. 1 , but with prime (′) marks. The differences in design are either discussed herein or apparent from a review of the drawings. As best shown in FIGS. 2 and 3 , a plenum 24 ′ of the apparatus 10 ′ is constructed with an angular plate structure 40 ′ that provides a larger plenum 24 ′ than plenum 24 and also provides a pair of openings 44 , 46 separated by a blocking portion 48 of the plate structure 40 ′. The plate structure includes sections 40 a ′, 40 b ′ oriented at acute angles, relative to vertical, for purposes of enlarging the plenum 24 ′ and assisting air flow. The plate structure 40 ′ extends from the top side 12 b ′ of the housing 12 ′ to the rear side 12 c ′ of the housing 12 ′. The separate openings 44 , 46 ensure that separate flows of cooling air are directed at the respective magnetrons 14 for more efficient and effective cooling of each magnetron 14 . For ease of comparison, the structure of apparatus 10 ′ is shown in solid lines, while the structure of the prior art apparatus 10 is shown in dash-dot lines in FIG. 4 . Thus, it will also be appreciated that the assembly of the magnetrons 14 and the lamp bulb 22 also have been moved, as a unit, closer to a window or open face 50 ′ of the housing 12 ′ as indicated by arrows 52 . In addition, the housing 12 ′ has been shortened by an amount indicated by the arrow 54 to thereby bring the window 50 ′ closer to the lamp bulb 22 . The width of the window 50 ′ (parallel to the lengthwise dimension of the lamp bulb 22 ) is also maximized to increase the area of ultraviolet light emission as much as possible.
[0025] As will be appreciated from the discussion to follow, these features help to provide a wider pattern of ultraviolet light emission from the window 50 ′ and, when multiple apparatus 10 ′ are mounted adjacent each other, helps to eliminate the striping issue discussed above. More specifically, because the assembly of the magnetrons 14 and the lamp bulb 22 has been moved closer to the window 50 ′, this effectively ensures that more of the scattered ultraviolet light at the ends of the window 50 ′ spreads farther outwardly onto the substrate 60 . The outward spreading of the light energy provides sufficient overlap between adjacent apparatus 10 ′ that the areas on the substrate 60 generally between the adjacent apparatus 10 ′ are sufficiently irradiated thereby providing uniform irradiation across the entire width of the substrate. This is accomplished while maintaining the proximity of the window 50 ′ at an optimal height or distance from the substrate, as opposed to moving farther from the substrate where the intensity of the ultraviolet radiation would be less.
[0026] FIG. 5 illustrates an enlarged cross sectional view of the lower end of the apparatus 10 ′ and, specifically, the lamp head 28 . This more specifically shows how the lowering of the magnetron assembly 14 ( FIG. 4 ) and lamp head 28 relative to the window 50 ′ provides a wider scatter pattern of ultraviolet light through the window 50 ′. These figures also show a substrate 70 located at an optimal distance or height “h” from the window 50 ′. As is known, and illustrated in FIG. 6 , a screen 71 is provided for preventing RF radiation or microwaves from passing through the window 50 ′, but allowing ultraviolet light to pass through. The scatter pattern of ultraviolet light is shown as occurring within angle β in FIG. 5 with the substrate 70 moving in a direction left to right or right to left as viewed in FIG. 5 . The scatter pattern β is relatively wide in this direction due to use of the reflectors 72 , 74 , as is known in the art.
[0027] Referring to FIG. 6 , in a direction perpendicular to that shown in FIG. 5 , (i.e., a width direction perpendicular to the path of the substrate) the scatter pattern of ultraviolet light is shown by arrows 80 to be a much smaller angle than the angle β in FIG. 5 . This is because the reflectors 72 , 74 ( FIG. 5 ) are not designed to reflect the light in these directions, but instead there is extraneously scattered light which is emitted in these directions. In this regard, FIG. 7 illustrates a view similar to FIG. 6 but showing apparatus 10 ′ of the invention. Apparatus 10 , of the prior art, has a scatter pattern of ultraviolet light that covers a width w 1 ( FIG. 6 ) which is less than the scatter pattern width w 2 ( FIG. 7 ) of apparatus 10 ′ with the window 50 ′ placed at the same optimal distance or height “h” from the substrate. The wider scatter pattern width w 2 is shown by arrows 90 and occurs due to the combination of the effects of lowering the magnetrons 14 ( FIG. 4 ) and lamp head assembly 28 ′ from the locations illustrated in dash-dot lines in FIG. 7 , to the locations shown in solid lines in FIG. 7 , in addition to slightly widening the window width from a width Ww 1 ( FIG. 6 ) to a width Ww 2 ( FIG. 7 ). It will also be appreciated that the dimensions of the lamp head 28 ′ have been changed relative to lamp head 28 , including shortening the structure forming the microwave chamber 16 ′.
[0028] As shown in FIGS. 8 , 8 A, 9 and 9 A, the effects of the changes discussed with regard to FIGS. 6 and 7 are schematically illustrated in a situation involving multiple apparatus 10 and 10 ′ respectively placed in adjacent, and more preferably abutting, contacting side-by-side relation above a wide substrate 70 , and at the optimal distance or height “h” from the substrate 70 . FIG. 8 illustrates the prior art apparatus 10 mounted in abutting, contacting relationship and with the lamp bulbs 22 in a colinear or coaxial relation to each other and the resulting scatter pattern of ultraviolet light indicated by the arrows 80 . This results in inadequately irradiated “stripe” or lengthwise area 82 along the substrate 70 (as viewed along the machine direction MD) because the ultraviolet light emitted between the two apparatus 10 does not irradiate the stripe area with sufficient intensity. As shown, the machine direction MD is perpendicular to the lengths of the respective bulbs 22 . On the other hand, with the apparatus 10 ′ of the invention in the same abutting, contacting side-by-side relation, the scatter pattern of ultraviolet light indicated by the arrows 90 is wider due to the effects of lowering the magnetron assemblies 14 ( FIG. 4 ) and lamp head 28 ′ and slightly widening the window 50 ′ such that the area 92 between the apparatus 10 ′ is irradiated with ultraviolet light of sufficient intensity to prevent the striping effect, as schematically illustrated in FIG. 9A . This is because the scatter patterns 90 spreading outwardly toward each other and between the adjacent apparatus 10 either meet or overlap at the surface of the substrate 70 , as shown in FIG. 9 .
[0029] While the present invention has been illustrated by the description of one or more embodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. The various features shown and described herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method and illustrative examples shown and described. Accordingly, departures may be from such details without departing from the scope of the general inventive concept. | An apparatus for generating ultraviolet light for irradiating a substrate. The apparatus includes a housing enclosing an interior space. The housing includes an inlet for receiving a cooling air flow, and a window configured to emit ultraviolet light and discharge the cooling air flow. A lamp bulb is mounted within the interior space between the inlet and the window. First and second microwave generators are mounted between the inlet and the lamp bulb. A plate is positioned between the inlet and the first and second microwave generators, the plate at least partially defining a plenum within the housing and including first and second openings generally aligned with the respective first and second microwave generators to direct first and second portions of the cooling air flow at the first and second microwave generators. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
Field of the Invention
[0004] The present invention concerns a protective pad that prevents damage to material that is subjected to compaction such as paver bricks. In particular, paver brick and other materials laid over a sand base often require compacting as part of the installation process. Current paver designs often include uneven top surfaces having peaks and valleys that mimic the contours of natural stone. However, when a motorized compactor having a metal base is passed over a peak, the peak is often marred and/or broken as a result of the compactor concentrating force on the peak. To solve this problem, one approach has been to place a soft pad made from rubber, silicone or urethane over the compactor's compaction plate and to bolt the rubber pad to the compactor.
[0005] Using a soft pad has several drawbacks. First, the pad will often rip at one or more mounting points on the compactor. Also, a compactor, which is typically gas powered, typically cannot be pulled in reverse and in other directions as a result of the flexible pad's tendency to bunch. This limits the range of motion of the compactor.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention provides solutions to the above-mentioned limitations of the prior designs. It provides an inflexible, non-metallic pad this resists tearing or ripping at an attachment point. It does not hinder compactor speed of operation or inhibit direction of movement. It is also fast and easy to attach and remove, saving time and effort, unlike. soft pads that need to be bolted after drilling holes into the compactor. Moreover, a universal attachment portion is freely positionable to permit mounting to many different compactor designs.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of an embodiment of the present invention.
[0008] FIG. 2A is a perspective view of another embodiment of the present invention.
[0009] FIG. 2B is a perspective view of yet another embodiment of the present invention.
[0010] FIG. 3 is a side view showing the universal positioning aspect of the attachment portion.
[0011] FIG. 4 is an explode side view.
[0012] FIG. 5 is a perspective view of another embodiment of the present invention.
[0013] FIG. 6 is a cross-sectional view of another embodiment of the present invention.
[0014] FIG. 7 illustrates an embodiment of the present invention in use.
[0015] FIG. 8 is a perspective view of another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] This 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. The scope of the invention is defined by the appended claims.
[0017] As shown in FIGS. 1 through 4 , the present invention includes a pad 100 having an inflexible or rigid planar portion 102 having an upwardly curved lip 104 connected to a hinge member 106 and an attachment portion 108 . Rigid planar portion 102 can be any substantially rigid or semi-rigid material, such as, but not limited to, plastic and other non-metallic materials. In one configuration, the planar portion may be made from a substantially sturdy rigid sheet material that has a small deflection when subject to a compacting force or when moved across a surface to be compacted. Suitable materials for pad 102 include, but are not limited to, acrylonitrile-butadiene-styrene, acrylic, chlorinated polyvinyl chloride, nylon, polycarbonate, polyethylene LOPE and HOPE, polypropylene, polyvinyl chloride, and styrene.
[0018] In addition, planar portion may also be a composite of rigid material sections 140 - 142 and a flexible material 150 which may be an elastomeric material. In addition, as shown in FIG. 6 , pad 600 may be a layered composite of a rigid material 602 and flexible material 630 .
[0019] As shown in FIGS. 2A , 2 B and 7 , planar portion is adapted to have sufficient rigidity and corresponding limited amount of deflection, or none at all, so as to maintain a co-planar relationship with a surface to be compacted 800 during the compaction process. In addition, the planar portion is also adapted to have sufficient rigidity to maintain a co-planar relationship with planar compaction plate 812 of compactor 810 during the operation of compactor 810 . This co-planar relationship is maintained for all directions of travel of compactor 810 .
[0020] Tapered edge 110 is located opposite tapered edge 105 formed by bend 104 . The edges, which oppose one another, allow for the smooth travel of the pad and compactor assembly over a surface that often includes loose material such as sand and the like. The edges may also be beveled, rounded and in other configurations.
[0021] As shown in FIG. 7 , pad 700 is attached to compactor 810 by clamps 720 and 722 which clamp attachment portion 708 to the machine. As a result of compactors having different angular front edges, in a preferred embodiment, pad 100 includes a hinged portion 106 , which allows attachment portion 108 to be positioned in a variety of angular positions such as 200 and 202 . Hinged portion 106 may be a mechanical hinge of a living hinge as shown. As shown in FIG. 4 , living hinge 106 is comprised of section 170 that connects sections 177 and 178 . To create the flexibility to form the hinge, section 170 may be substantially less in thickness than sections 177 and 178 . In a preferred configuration, section 170 is 75 percent thinner than the other sections.
[0022] In addition, hinge 106 may face the compactor or it may face way from the compactor such as shown in FIG. 5 for hinge 506 . Even with the hinge facing away from the compactor, attachment portion 508 may still he affixed to a device by clamps 520 and 522 . In addition, a pad may he affixed to a compactor by bolts, screws, fasteners, rivets and in other ways known to those of skill in the art.
[0023] FIG. 8 depicts another embodiment, which requires no mechanical affixation of pad 850 to a compactor. In this embodiment, the device is comprised of planar surface 802 which may be of a composition as described above. In addition, pad 802 is connected to sidewalk 810 - 813 which, together, form a semi-enclosed housing or structure in which a compactor nests or may be placed. The sidewalk maintain the compactor within the device during operation. In addition, the sidewalls may also be angled or tapered to allow for the smooth travel of the pad and compactor assembly over a surface that often includes loose material such as sand and the like. The edges may also be beveled, rounded and in other configurations. | What is disclosed is a pad for use with a compactor having a planar plate for protecting material to he protected. The pad includes a rigid planar surface adapted to maintain a co-planar relationship with the plate of the compactor during the operation of the compactor. The pad is adapted to be affixed to the compactor by clamps and other mechanical means. | 4 |
TECHNICAL FIELD
[0001] Generally, this invention relates to vacuum cleaners. In particular, the invention relates to a removable dirt separation system for a vacuum cleaner. Moreover, the invention relates to a removable dirt separation system for use in a bagless vacuum cleaner.
BACKGROUND OF THE INVENTION
[0002] Upright vacuum cleaners are well known in the art. Typically, these vacuum cleaners include an upper housing pivotally mounted to a vacuum cleaner foot. The foot is formed with a nozzle opening defined in an underside thereof and may include an agitator mounted therein for loosening dirt and debris from a floor surface. A motor and fan may be mounted to either the foot or the housing for producing suction at the nozzle opening. The suction at the nozzle opening picks up the loosened dirt and debris and produces a flow of dirt-laden air which is ducted to the vacuum cleaner housing.
[0003] In conventional vacuum cleaners, the dirt laden air is ducted into a filter bag supported on or within the vacuum cleaner housing. Alternatively, bagless vacuum cleaners duct the flow of dirt-laden air into a dirt separation system having a dirt cup which filters the dirt particles from the airflow before exhausting the filtered airflow into the atmosphere. Various dirt separation systems have been used on bagless vacuum cleaners to separate the dirt particles from the airflow. For example, some vacuum cleaners have dirt cups with outer walls comprising a filter material. Locating the filter material along the outer walls has the distinct advantage of permitting the use of a large amount of filter material similar to the amount of material in a filter bag. However, such vacuum cleaners have a disadvantage of not permitting the operator to view the accumulated material within the dirt cup. Other vacuums, place the filter element in an interior portion of the dirt cup. Such dirt cups do not take advantage of the larger surface available on the outer wall of the dirt cup.
[0004] What is needed therefore, is a dirt separation system that overcomes the above-mentioned drawbacks.
SUMMARY OF THE INVENTION
[0005] In accordance with a first aspect of the present invention, there is provided a removable dirt separation system for a vacuum cleaner. The dirt separation system includes a dirt cup having a bottom wall and at least one vertically extending side wall and a filter assembly removably mounted in an upper portion of the dirt cup and having a generally horizontal screen element, an exit above the screen, and a filter covering the exit. The dirt separation system further includes a flow directing nozzle disposed in the dirt cup to direct an air stream generally parallel to a surface of the screen element. Particles in the air stream are primarily separated by the screen element. Particles in the air stream are secondarily separated by the filter element.
[0006] In accordance with a second aspect of the present invention, there is provided an upright vacuum cleaner. The upright vacuum cleaner includes a carpet engaging nozzle base and an upper housing pivotally connected to the nozzle base. The upright vacuum cleaner further includes a duct opening in said upper housing and a dirt cup removably secured to the upper housing and having a bottom wall and a number of vertically extending sided walls. The upright vacuum cleaner yet further includes a filter assembly removably mounted in an upper portion of the dirt cup and having a generally horizontal screen element, an exit above the screen element, and a filter covering the exit. The upright vacuum cleaner still further includes a flow directing nozzle fluidly connected to the duct and disposed to direct an air stream generally parallel to a surface of the screen element. Particles in the air stream are primarily separated by the screen element. Particles in the air stream are secondarily separated by the filter element.
[0007] In accordance with a third aspect of the present invention, there is provided a method of operating a removable dirt separation system for a vacuum cleaner. The vacuum cleaner includes a dirt cup and a filter assembly removably mounted in an upper portion of the dirt cup and having a generally horizontal screen element, an exit above the screen element, and a filter covering the exit. The method includes the step of directing an air stream generally parallel to a surface of the screen element via a flow directing nozzle. The method further including the steps of primarily separating particles from the air stream with the screen element and secondarily separating particles from the air stream with the filter element.
BRIEF DESCRIPTION OF DRAWINGS
[0008] FIG. 1 is a perspective view of an upright vacuum cleaner which incorporates the features of the present invention therein;
[0009] FIG. 2 is a perspective view similar to FIG. 1 , but showing a dirt separation system removed from the vacuum cleaner;
[0010] FIG. 3 . is a perspective view of the dirt separation system of FIG. 2 with a filter assembly removed;
[0011] FIG. 4 . is an exploded perspective view of the filter assembly of the dirt separation system of FIG. 3 ;
[0012] FIG. 5 is a cross-sectional view of the dirt separation system of FIG. 2 , taken along the line 5 - 5 ;
[0013] FIG. 6 is a side view of an upper portion of the vacuum cleaner shown in FIG. 1 , showing a bucket handle in a first position;
[0014] FIG. 6A is an enlarged cutaway view of a portion of the vacuum cleaner of FIG. 6 ;
[0015] FIG. 7 is a view similar to FIG. 6 , but showing the bucket handle in a second position;
[0016] FIG. 7A is an enlarged cutaway view of a portion of the vacuum cleaner of FIG. 7 ;
[0017] FIG. 8 is a side view of the removable dirt separation system of FIG. 2 in a carry position;
[0018] FIG. 9 is a view similar to FIG. 8 , but showing the filter assembly removed and a dirt cup in an empty position;
[0019] FIG. 10 is a cross-sectional view of the upper housing of the vacuum cleaner of FIG. 6 , taken along the line 10 - 10 showing the air flow within the upper housing;
[0020] FIG. 11 is a cross sectional view of the upper housing and dirt cup of the vacuum cleaner of FIG. 6 , taken along the line 11 - 11 showing the air flow around the dirt cup;
[0021] FIG. 12 is a front view of the upper housing of the vacuum cleaner of FIG. 2 , as viewed along the line 12 - 12 showing the air flow around the exterior of the upper housing;
[0022] FIG. 12A is an enlarged view of a portion of upper housing shown in FIG. 12 ;
[0023] FIG. 13 is a partial cut away perspective view of an upper portion of the vacuum cleaner showing the handle locking mechanism;
[0024] FIG. 14 is a partial cross sectional view of the upper housing of FIG. 13 , taken along the line 14 - 14 and showing the latch in a latched position;
[0025] FIG. 15 is a view similar to FIG. 13 , but showing the latch in a release position;
[0026] FIG. 16A is a view similar to FIG. 14 , but showing the latch in a release position and the handle in an operational position;
[0027] FIG. 16B is a view similar to FIG. 16A , but showing the handle in a storage position;
[0028] FIG. 17 is a perspective view of the base of the vacuum cleaner shown in FIG. 1 ;
[0029] FIG. 18 is a cross sectional view of the base of the vacuum cleaner of FIG. 17 , taken along the line 18 - 18 showing the blocker door in a closed position; and
[0030] FIG. 19 is a cross sectional view similar to FIG. 18 but showing the blocker door in an open position.
DETAILED DESCRIPTION
[0031] While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
[0032] Referring now to FIG. 1 , there is shown an upright vacuum cleaner 10 which incorporates the features of the present invention therein. The vacuum cleaner 10 includes a vacuum cleaner base 12 and a vacuum cleaner upper housing 20 pivotally connected to the base 12 . The base 12 is adapted to engage a carpeted floor surface. The base 12 includes a nozzle opening 14 formed in an underside thereof for suctioning of dirt particles from a carpeted floor surface. In addition, an agitator 154 (see FIG. 18 ) is positioned within the nozzle opening 14 to assist in removing dirt particles from the carpeted floor surface.
[0033] Referring now to FIG. 2 , there is shown the vacuum cleaner of FIG. 1 , with a dirt separation system 30 removed from the upper housing 20 . The upper housing 20 includes an inlet interface 22 in fluid communication with the nozzle opening 14 . The upper housing 20 further includes an outlet interface 24 for exhausting filtered air from the removable dirt separation system 30 . A motor-fan unit 26 (See FIG. 10 ) is positioned in a lower portion of the upper housing 20 and is adapted to generate an airflow from the nozzle opening 14 to the outlet interface 24 . In this type of vacuum cleaner, the motor-fan unit 26 is positioned downstream from the outlet interface 24 such that the low pressure at a fan inlet 127 creates an airflow that draws low pressure air from the nozzle opening 14 to the outlet interface 24 via the inlet interface 22 and dirt separation system 30 . The air which reaches the motor-fan unit 26 has been filtered by the dirt separation system 30 prior to reaching the motor/fan unit 26 , hence these vacuums are generally referred to as “clean air” units. The air which exits the motor-fan unit 26 is then exhausted from the vacuum cleaner 10 .
[0034] In another type of vacuum cleaner, the motor-fan unit 26 is positioned between the nozzle opening 14 and the inlet interface 22 such that the low pressure at the fan inlet creates a suction in the nozzle opening 14 . This suction draws the loosened dirt from the floor surface into nozzle opening 14 and creates a flow of dirt-laden air which travels through the motor-fan unit 26 . The flow of dirt-laden air is blown upwardly through the inlet interface 22 through the dirt separation system 30 , through the outlet interface 24 and exhausted from the vacuum cleaner 10 . The air which reaches the motor-fan unit 26 has not been filtered either by the dirt separation system 30 or a bag prior to reaching the motor/fan unit 26 , hence these vacuum cleaners are generally referred to as “dirty air” units. It should be appreciated that the inventions described herein may be used in either a dirty air unit or a clean air unit without deviating from the scope of the invention.
[0035] Referring now to FIG. 3 , there is shown an exploded view of the dirt separation system 30 with a filter assembly 40 removed to show the interior of a bucket, or dirt cup 50 . The dirt cup or bucket 50 has a distinctive bucket handle 52 rotatably attached thereto. The dirt cup 50 also includes a number of sidewalls 54 which define the exterior of the dirt cup 50 . The bucket handle 52 is movable between a generally vertical first position, shown in FIG. 1 , a generally vertical carry position, shown in FIG. 2 , an emptying position shown in FIG. 9 , and a generally horizontal second position, shown in FIG. 3 . The filter assembly 40 includes a lid member 41 having an exit opening 42 defined therethrough. A compressible seal 46 around the periphery of the exit opening 42 is adapted to seal against the exit interface 24 (See FIG. 2 ) of the upper housing 20 . The lid member 41 further includes a sealing arrangement 44 around the periphery of the lid member 41 . The sealing arrangement 44 is bonded to the lid member 41 and is adapted to engage and seal against one or more of the side walls 54 of the dirt cup 50 to prevent dirt laden particles from bypassing the exit opening.
[0036] Referring now to FIG. 4 , there is shown an exploded view of the filter assembly 40 . The filter assembly 40 further includes a removable filter 60 . The removable filter 60 includes a base plate 64 , a sealing plate 62 with a filter exit 66 (See FIG. 5 ) defined therethrough, and a vertically extending filter element 68 . The filter element 68 includes a first inner layer formed of a melt-blown polypropylene, a second middle layer formed of a spun-bond polyester and an outer third layer formed of an expanded polytetrafluoro-ethylene (ePTFE) membrane. The ePTFE outer layer provides non-stick properties to the filter element 68 and allows any dirt or dust accumulated on the filter element 68 to be easily displaced therefrom. Although the filter element 68 is shown and described as having three layers, it is understood that the filter material may include any number of layers or be formed of any number of materials such as a micro-glass or a melt-blown polyester without affecting the concept of the invention.
[0037] The filter exit 66 is adapted to seal to an extension 48 of the lid member 41 to place the exit opening 42 of the lid 41 in fluid communication with the filter exit 66 . A upper edge of the filter element 68 is bonded to the sealing plate 62 and a lower edge of the filter element 68 is bonded to the base plate 64 . The base plate 64 and sealing plate 62 form a generally oval shape around the exit opening 42 of the lid member 41 . This oval shape provides a significant amount of filter material to be placed within small volume.
[0038] The filter member 68 is pleated around the oval track formed by the base plate 64 and sealing plate 62 to further increase the effective filter area of the filter member 68 . It should be appreciated that once the removable filter 68 is assembled to the lid member 41 and the lid member 42 is placed in the dirt cup 50 , the airflow from the dirt cup 50 may only exit through the exit opening 42 via the filter element 68 , as the sealing arrangement 44 prevents air flow from by-passing the filter element 68
[0039] The filter assembly 40 further includes a screen support 70 which surrounds the removable filter 60 . The screen support 70 includes a number of horizontal openings 74 defined therethrough which place the interior of the screen support 70 in fluid communication with the exterior of the screen support 70 . In addition, a screen element 76 covers each of the screen openings 74 . The screen elements 76 may be formed of a number of different materials such as metal or synthetic mesh or screens, cloth, foam, a high-density polyethylene material, apertured molded plastic or metal, or any other woven, non-woven, natural or synthetic coarse filtration materials without affecting the scope of the invention. It should be appreciated that the screen element 76 separate dirt particles from an air stream prior to those particles reaching the filter element 68 of the filter 60 .
[0040] The screen support 70 further includes a catch 78 defined thereon which is adapted to be engaged by a latch 49 of the lid member 41 . The screen support 70 is attached to the lid member 41 when the latch 49 engages the catch 78 . Alternatively, the screen support 70 may be removed from the lid member 41 when the latch 49 is disengaged from the catch 78 .
[0041] Referring now to FIG. 5 , there is shown a cross sectional view of the dirt separation system 30 . When the dirt cup separation system 30 is secured to the upper housing 20 , as shown in FIG. 1 , the vacuum cleaner is placed in an operational mode. As shown, the dirt cup 50 further includes a bottom wall 55 having an inlet 56 defined therethrough. The inlet 56 seals against the inlet interface 22 of the upper housing 20 to place the dirt cup 50 in fluid communication with the agitator chamber 14 . The dirt cup 50 further includes a conduit 57 which directs a dirt laden air stream from the inlet 56 to a flow directing nozzle 58 , as indicated by arrow 80 . The flow-directing nozzle 58 creates a sheet-like airflow, indicated by arrow 81 , which is generally parallel to the screen elements 76 of the filter assembly 40 . It should be appreciated that the air flow created by the flow directing nozzle 58 prevents dirt particles from accumulating on the screen elements 76 of the filter assembly 40 . From the flow-directing nozzle 58 , the air stream generally settles in an expansion chamber 59 wherein inertial and gravitational forces separate large particles from the air stream, as the air stream is generally directed as indicated by arrows 82 .
[0042] The air stream exits the expansion chamber 59 via the screen elements 76 . The screen elements 76 act as a primary separation means to separate coarse particles from the air stream which exits the expansion chamber 59 . The air stream then generally passes (i) vertically through the screen elements 76 , (ii) horizontally outwardly through a gap created between the screen elements 76 and the base plate 64 by tabs 78 , vertically along an exterior of the filter 60 , and horizontally toward the filter element 68 , as generally indicated by the arrows 83 . The filter element 68 act as a secondary separation means to separate fine particles from the air stream which exits the expansion chamber 59 . The filter assembly 40 has the advantage of horizontal screen elements 76 which are cleaned by the nozzle 58 combined with the vertical filter element 68 which provides a relatively large filter area. The filtered air stream then exits the dirt separations system 30 via the exit opening 42 in the general direction of arrows 84 . It should be appreciated that the exit opening 42 seals against the exit interface 24 (see. FIG. 2 ) of the housing when the dirt separation system 30 is secured to the upper housing (as shown in FIG. 1 ).
[0043] Referring now to FIGS. 6 and 6 A, there is shown a side view of the upper housing 20 showing the bucket handle 52 in the first position. In the first position, the handle 52 is substantially vertical. Furthermore, the bucket handle 52 is substantially flush with a surface 13 of the upper housing 20 . The bucket handle 52 is rotatably mounted to the dirt cup or bucket 50 about a hub 53 such that the bucket handle 52 may rotate relative to the bucket 52 about the hub 53 in the general direction of arrows 99 and 100 . FIG. 6A shows an enlarged portion of a latch portion 90 of the bucket handle 52 . The latch portion 90 engages a catch 15 defined in the upper housing 20 as the bucket handle 52 is rotated in the general direction of arrow 100 . In particular, an extension 92 of the latch portion 90 engages a detent defined in the catch 15 . Thus, the latch portion 90 of the bucket handle 52 secures the bucket or dirt cup 50 to the upper housing 20 when the bucket handle 52 is positioned in the first position. When the bucket or dirt cup 52 is secured to the upper housing 20 , the vacuum cleaner is placed in an operational mode whereby an air stream may be advanced from the nozzle 14 to the dirt separation system 30 where particles are separated from the air stream by the filter assembly 40 .
[0044] Referring now to FIGS. 7 and 7 A, there is shown the bucket handle 52 in second position. In the second position, the handle 52 is moved toward a horizontal plane from the first position shown in FIG. 6 . FIG. 7A shows an enlarged partially cut-away of the latch portion 90 of the upper handle 52 in the second position. The latch portion 90 releases the catch 15 defined in the upper housing 20 as the bucket handle 52 is rotated in the general direction of arrow 99 . In particular, an extension 92 of the latch portion 90 disengages the detent defined in the catch 15 . Thus, the latch portion 90 of the bucket handle 52 releases the bucket or dirt cup 50 from the upper portion 20 when the handle 52 is positioned in the second position.
[0045] Referring now to FIG. 8 , there is shown the dirt separation system 30 in a carry position. Once the dirt cup or bucket 52 is released from the upper housing 20 , as described above, an operator may grasp the bucket handle 52 and carry the dirt separation system 30 to a dirt receptacle (not shown).
[0046] Referring now to FIG. 9 , there is shown the dirt separation system 30 in an emptying position. To move the dirt separation system 30 from the carry position to the emptying position, the filter assembly 40 is removed from the dirt cup 50 , and the dirt cup 50 is rotated in the general direction of arrow 99 relative to the handle 52 to allow the contents of the dirt cup 50 to be emptied in the dirt receptacle. The filter assembly 40 may be further cleaned by detaching the screen support 70 and the filter 60 from the lid member 41 , as shown in FIG. 4 . Once detached, the screen elements 76 and filter element 68 may be cleaned by the operator. The filter assembly 40 may be reassembled and repositioned within the dirt cup or bucket 50 and the dirt separation system 30 returned to the carry position (shown in FIG. 8 ). Once in the carry position, the dirt cup 50 may be moved from the dirt receptacle to the vacuum cleaner 10 . The dirt separation system 30 may then be repositioned in the upper housing 20 as shown in FIG. 7 . The dirt cup or bucket 50 may then be secured to the upper housing 20 by moving the bucket handle 52 from the second position of FIG. 7 to the first position of FIG. 6 , as described above. Securing the dirt cup to the upper housing places the vacuum cleaner in an operational mode.
[0047] Referring now to FIG. 10 , there is shown a cut-away view of the internal airflow path within the upper housing 20 , as taken along the line 10 - 10 of FIG. 6 . Airflow from the nozzle 14 is directed to the inlet interface 22 via a hose 170 , shown in FIGS. 18 and 19 . From the inlet interface 22 , dirt enters the dirt separation system 30 via the inlet 56 and exits the dirt separation system 30 via the exit opening 42 as described above in connection with FIG. 5 above. The exit opening 42 is sealed against the exit interface 24 . From the exit interface 24 , filtered air is directed to an inlet 27 of the motor-fan unit 26 via a fan duct 110 . The fan duct 110 within the housing 20 extends substantially the entire length of the dirt cup 50 as the exit interface 24 is positioned above of the dirt cup 50 . It should be appreciated that the length of the fan duct 110 muffles noises created by the motor-fan unit 26 . After exiting the motor fan unit 26 via the exit 28 , the air flow is directed upwardly by a fan exhaust duct 112 . The fan exhaust duct 112 directs the air flow to a final filter 116 comprising a filter element 117 and a filter retainer 118 (shown in FIG. 2 ). The fan exhaust duct 112 also extends substantially the entire length of the dirt cup 50 . It should further be appreciated that the length of the fan exhaust duct 112 helps muffle noises created by the motor-fan unit 26 .
[0048] Referring now to FIG. 11 , there is shown a cross sectional view of a portion of the upper housing 20 with the dirt cup 50 placed in the operational mode. The airflow which passes through the filter 116 exits the upper housing 20 into an expansion chamber 120 and travels generally laterally in the vacuum cleaner 10 in the general direction of arrows 101 . The expansion chamber 120 is an expanding area defined between a portion of the upper housing 20 and a number of side walls 54 of the dirt cup 50 which allows the airflow to diffuse prior to exiting the vacuum cleaner 10 . The expansion chamber 120 provides a significant reduction in the sound created by the motor/fan unit 26 . The dirt cup 50 further includes a number of lateral extensions 55 which cooperate with surfaces 114 of the upper housing 20 to define an expansion chamber exit 122 . After passing through the expansion chamber 120 , the muffled air flow is allowed to exit the vacuum cleaner 10 along the length of the expansion chamber exit 122 , in the general direction arrow 102 , at a reduced velocity and sound level. The length of the expansion chamber exit 122 can best be seen in FIG. 1 .
[0049] Referring now to FIGS. 12 and 12 A, there is shown the air flow within the expansion chamber 120 having the dirt separation system 30 removed for clarity of description. In particular, it can be seen that the airflow indicated by the arrows 101 and 102 is vertically distributed along the height of the expansion chamber 120 . In addition, it should be noted that a number of vanes 124 are attached to the upper housing 20 . These vanes 124 direct the airflow away from the base 12 . As the upwardly directed airflow passes through the expansion chamber exit 122 , it does not disturb the surface being cleaned by the vacuum cleaner 10 . In addition, it should be appreciated that the vanes 124 could alternately be placed on the lateral extensions 55 of the dirt cup 50 to direct the airflow away from the base 12 .
[0050] Referring now to FIG. 13 , there is shown a handle 130 positioned in an operational position. The handle 130 is rotatably mounted to the upper housing 20 . The handle 130 rotates about a round axle extension 132 attached to a lower portion of the handle 130 . This arrangement allows the handle 130 to rotate about the axel extension 132 in the direction of arrows 99 and 100 . A latch 140 is provided to secure the handle 130 in the operational position. The latch 140 rotates about an axel 142 in the general direction of arrows 99 and 100 . The axis of rotation of the latch 140 about the axel 142 is offset from the axis of rotation of the handle 130 about the axle extension 132 such that the latch 140 may engage exterior portions of the handle 130 . A spring 143 interposed between the housing 20 and the latch 140 biases the latch 140 in the general direction of arrow 99 . A lever 144 is secured to the axel 142 . An extension of the lever 144 is the actuator 145 which extends through the housing 20 and allows and operator to rotate the latch 140 in the general direction of arrow 100 by depressing the actuator 145 . The textured surface 146 of the actuator assists the operator in moving the actuator 145 .
[0051] Referring now to FIG. 14 , there is shown a partial schematic view of the engagement of the latch 140 with the handle 130 . In particular, as the spring 143 biases the latch 140 in the general direction of arrow 99 , the latch 140 engages a notched engagement surface 134 of the handle 130 . Biasing the latch 140 against the engagement surface 134 places the latch 140 in the locked position which holds the handle 130 in an operational position. It should be appreciated that the latch 140 engages the handle 130 over substantially the entire width of the handle 130 to provide a substantial latching force between the handle 130 and the latch 140 .
[0052] Referring now to FIG. 15 , there is shown the latch 140 in the release position, which allows the handle 130 to be placed in a storage position. To place the latch in the release position, the operator moves the actuator 145 in the general direction of arrow 100 by overcoming the biasing force of the spring 143 and rotating the latch 140 in the general direction of arrow 100 . Placing the latch 140 in the release position, moves the latch 140 out of contact with the notched engagement surface 134 of the handle 130 thereby allowing the handle 130 to be rotated in the general direction of arrow 100 (see. FIG. 16A ). The handle 130 may then be freely rotated in the general direction of arrow 100 as the latch 140 slides along an arcuate surface 136 of the handle 130 when the latch is in the release position (see FIG. 16B ). Thus, the handle 130 may be placed in the storage position shown in FIGS. 15 and 16 B. To move the handle to the operational position from the storage position, the operator rotates the handle 130 in the general direction of arrow 99 until the biasing force of the spring 143 causes the latch 140 to engage the notched engagement surface 134 of the handle 130 , as shown in FIG. 14 .
[0053] Referring to FIGS. 17-19 , there is show the base 12 of the vacuum cleaner 10 . The base 12 further includes a duct 150 placed in fluid communication with an agitator chamber 152 having a rotating agitator 154 positioned within. The base 12 further includes a blocker door 160 movable between a closed position (shown in FIGS. 17 and 18 ) and an open position (shown in FIG. 19 ). When the blocker door 160 is placed in the open position, a flexible hose 170 may be placed on the outer surface of the duct 150 . The flexible hose 170 is in fluid communication with the inlet interface 22 (shown in FIG. 2 ). The flexible hose 170 is in further fluid communication with the dirt separation system 30 and motor/fan unit 26 when the vacuum cleaner 10 is in the operational position. Thus, when the motor/fan unit 26 is operating, suction from the motor fan unit 26 , is transmitted to an end 172 of the hose 170 . For carpet cleaning, the hose 170 is attached to the duct 160 to further place the hose 170 in fluid communication with the nozzle opening 14 . For above the floor cleaning, which typically involves placing tools (not shown) on the end 172 of the hose 170 , the hose 170 is disconnected from the duct 160 . When the hose 170 is disconnected from the duct 160 , it is desirable to prevent access to the agitator chamber 152 via the duct 150 . Thus, it is desirable for the blocker door 160 to move into the closed position shown in FIGS. 17 and 18 when the hose 170 is disconnected from the duct 160 .
[0054] Referring now to FIGS. 18 and 19 , the base 12 further includes an arcuate track 156 defined therein. The arcuate track 156 is adapted to engage an arcuate surface 162 of the blocker door 160 such that the blocker door 160 may slide and rotate relative to the base 12 in the general direction of arrows 199 and 200 . The blocker door 160 further includes a tab 164 which passes through a slot 158 defined in the track 156 . A spring 180 is interposed between the tab 164 and the base 12 to bias the tab 164 in the general direction of arrow 182 . It should be appreciated that biasing the tab 164 in the general direction of arrow 182 also biases the blocker door 160 in the general direction of arrow 200 to place the blocker door in the closed position shown in FIGS. 17 and 18 .
[0055] In operation, when the flexible hose 170 is disconnected from the duct 160 , the biasing force of the spring 180 causes the blocker door 160 to slide in the general direction of arrow 200 and place the blocker door 160 in a closed position. Placing the blocker door 160 in the closed position blocks access to the agitator chamber 152 via the duct 160 (see FIGS. 17 and 18 ). To return the vacuum cleaner 10 to a floor cleaning mode, the flexible hose 170 is connected to the duct 150 . To accomplish this, an operator may press on an upper surface of the blocker door 160 to cause the blocker door to slide along the track 156 and rotate in the general direction of arrow 199 . As the biasing force of the spring 180 is overcome, the blocker door 160 is placed in the open position shown in FIG. 19 and the flexible hose 170 may be connected to the duct 160 . It should be appreciated, that the end 172 of the flexible hose 170 may also be used to slide the blocker door 160 along the track 156 the closed position to the open position, thus allowing an operator of the vacuum cleaner 10 to connect the flexible hose 170 to the duct 150 using a single hand.
[0056] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as exemplary 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. | A vacuum cleaner includes a dirt separation system that has a dirt cup retaining a filter assembly having a screen element, an exit, and a filter element disposed between the screen element and the exit. A nozzle disposed in the dirt cup directs an airstream generally parallel to the surface of the screen element so that particles in the airstream are primarily separated by the screen element and, as the airstream ultimately travels towards the exit in the dirt cup, are secondarily separated by the filter element. | 8 |
Pursuant to 35 U.S.C. Section 202(c), it is acknowledged that the United States Government has certain rights in the invention described herein, which was made in part with funds from the Department of Defense, Grant No. DAMD17-99-1-9313.
BACKGROUND OF THE INVENTION
The present invention relates generally to targeted therapy and medical imaging as applied to cancer treatment and diagnosis, and in particular to conjugates composed of a radiolabeled, cell cycle-dependent therapeutic agent chemically coupled to a ligand that targets androgen receptor (AR). The conjugates of the invention are taken up selectively by malignant tumor cells that have androgen receptor and are incorporated into the nucleus of such cells, where they produce a cytotoxic effect and/or are detectable via radioimaging techniques.
The main treatments for breast, prostate, ovarian and many other cancers are surgery, chemotherapy and radiation therapy. In some cases a combination of two or more of these treatments is recommended. Typically, clinical trials for advanced carcinomas use combination chemotherapy based on established anti-cancer agents. For example, there are numerous active clinical trials (Phase I) dealing with recurrent and progressive ovarian carcinoma that rely on existing drugs such as paclitaxel, carboplatin, cisplatin, floxouridine and similar drugs in a combination chemotherapy. Many of these include an autologous stem cell support to combat the side effects brought on by the administration of these drugs. Newer drugs include matrix metalloproteinase inhibitors, vaccines, and antibodies.
Many of the currently available front-line and salvage agents used in cancer therapy are associated with cumulative and/or irreversible toxicities that pose challenges for long-term treatment planning. The irreversible effects associated with some of these therapies include development of multidrug resistance, neurotoxicity, and nephrotoxicity. All of these diminish the probability of improved responses when multiple treatments are needed to keep the cancer under control.
It has previously been proposed to use targeted cytotoxic radioisotopes for the treatment and diagnosis of cancer. One of the intended benefits of targeted therapy is to diminish the incidence and severity of side effects by confining toxic exposure, more or less, to the disease site. Certain radioisotopes, particularly Auger electron-emitting isotopes, such as 123 I and 125 I are known to be very toxic to viable cells, but only if they are localized within the nucleus of the cell. (Warters et al., Curr. Top. Stop Rad. Res., 12:389 (1977).) It has been reported that 5′-iodo-2′-deoxyuridine (IUdR), when labeled with the Auger electron emitter 123 I or 125 I exhibits substantial toxicity in mammalian cells in vitro (Makrigiorgos et al., Radiat. Res., 118:532–44 (1989)) and produces a therapeutic effect in animal tumor models (Baranowska-Kortylewicz et al., Int. J. Radiat. Oncol. Biol. Phys., 21:1541–51 (1991)). Furthermore, radiolabeled IUdR has been found to enable scintigraphic detection of animal and human tumors (Baranowska-Kortylewicz, supra). See also U.S. Pat. Nos. 5,094,835 and 5,308,605.
Considerable effort has been devoted to developing antibodies for the targeted delivery of therapeutic and diagnostic agents. However, antibodies themselves have not been capable of reaching the cell nucleus in effective amounts. Most such antibodies react with the cell surface, and are gradually internalized, routed to lysosomes and degraded (Kyriakos et al., Cancer Res., 52:835 (1992)). Degregation products, including any radioisotopes attached thereto, then gradually leave the cell by crossing the lysosomal membrane and then the cell membrane. Although a conventional radioisotope label on an antibody degradation product can theoretically pass through the nuclear membrane and deliver some radioactivity to the nucleus (Woo et al., WO 90/03799) actual observations show that the amount is limited, and in any event, is insufficient to have a toxic effect on tumor cells.
Protein and polypeptide hormones and growth factors, particularly those having cell surface receptors, may be directly radiolabeled and used to target a tumor cell. As in the case of targeting radiolabeled antibodies, however, radioisotopes bound to amino acid residues of hormones, growth factors and the like exit from the cell after catabolism, and do not appreciably bind to nuclear material.
Despite the many advances in the field of cancer therapy and diagnosis, there remains an acute need for innovative treatment methods, particularly for cancers having high instances of relapse, which can be safely applied in a repetitive, long-term regimen, without the side effects produced by existing treatments.
SUMMARY OF THE INVENTION
The above-noted need is satisfied by the radiolabeled conjugates of the present invention which are capable of targeting and being selectively taken up and degraded by a tumor cell, and thereby delivering to the tumor cell nucleus a radioisotope capable of being incorporated into the nuclear material, so as to produce a cytotoxic effect and/or to render the cell detectable by radioimaging. The conjugates of the invention can be safely administered in long term cancer treatments, without producing significant adverse health effects.
In accordance with one aspect of the present invention, there is provided a cancer-specific radiolabeled conjugate of the formula:
wherein B* represents uracil substituted with a radionuclide; R represents H, OH, or O-L-DHT, L being a cleavable bifunctional linking moiety and DHT is 4-dihydrotestosterone, which is bound through its hydroxyl substituent to said linking moiety; and R′ represents a phospho group or a substituted phospho group having the formula —PO(OR a ) (OR b ), —PO(OR a )(ODHT) or —PO(ODHT) 2 , R a and R b being the same or different and representing H or lower alkyl and DHT is as previously defined, with the proviso that at least one of the R and R′ substituents comprises a DHT moiety.
The present invention also provides methods of using the above-described conjugate for treating and diagnosing cancers comprising cells having AR, especially ovarian, breast and prostate cancer.
The conjugates of the present invention have been designed so as to take advantage of two characteristics of many relapsing cancers, i.e. (1) relapsed/advance cancers have a large portion of rapidly growing and dividing cells (i.e. a large S-phase fraction); and (2) AR is expressed in practically all prostate cancer (primary and metastatic), ovarian cancer (>90% positive for AR regardless of the tumor site) and breast cancer (even when estrogen receptor (ER)-negative and progesterone receptor (PR)-negative, breast cancer cells express AR). Upon administration, the conjugate first binds to the sex hormone binding globulin, which in turn carries it exclusively to cells that have AR. Subsequent to this interaction, the entire conjugate is transported into the cell. Intracellular enzymes cleave the linking moiety, thus releasing and trapping within the cell the portion of the conjugate that is responsible for killing tumor cells. This cytotoxic effect is induced only when the cell cycle dependent therapeutic agent is incorporated into the DNA of dividing tumor cells. This dependence of radiotoxicity on the participation of the radiolabeled agent in DNA synthesis, in combination with relatively rapid pharmacokinetics, limits the exposure of normal tissue to radiation. In other words, the conjugate that remains in systemic circulation, or enters normal tissue or organs, is essentially innocuous. Accordingly, the radiolabeled conjugates of the invention may be administered frequently and without adverse effects.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a set of two graphs depicting the binding of 125 IUdR-DHT to OVCAR-3 cells in vitro. FIG. 1A plots the fraction of “bound” counts to “free counts” against “bound” 125 IUdR-DHT (mM). FIG. 1B plots bound 125 IUdR-DHT (mM) against free 125 IUdR-DHT (mM).
FIG. 2 is a set of two graphs depicting the stability of 125 IUdR-DHT. FIG. 2A depicts the stability of 125 IUdR-DHT with time in the presence or absence of OVCAR-3 cells. FIG. 2B depicts the kinetics of the emergence of 125 IUdR in the medium in the presence or absence of OVCAR-3 cells.
FIG. 3 is a graph showing the HPLC profiles of 5′-MP- 125 IUdR-3′-DHT with SHBG in the presence or absence of DHT.
FIG. 4 is a graph sowing the tumor uptake of 5′-MP- 125 IUdR-3′-DHT in athymic mice (bars) and the amount of DNA-bound 125 IUdR (line).
FIG. 5 is a set of two graphs showing the in vivo uptake of 125 IUdR-3′-DHT by OVCAR-3 tumors in athymic mice (A) and the amount bound to DNA (B) over time.
DETAILED DESCRIPTION OF THE INVENTION
The conjugates of the present invention are composed of one component which is effective for killing cancer cells that make DNA and multiply and another component that is capable of specifically targeting AR expressed by cancer cells.
Thymidine analogs, such as IUdR, have certain characteristics which make their radiolabeled derivatives useful for the treatment or diagnosis of tumors whether macroscopically observable or not. Because such thymidine analogs are low-molecular-weight molecules, they diffuse readily within tissues. IUdR, for example, when radiolabeled with an Auger electron emitter, such as, 123 I, 125 I, 77 Br, 80m Br, 195m Hg, and 113 Sn, is innocuous outside the cell and ineffective at killing cells when within the cytoplasm. IUdR may also be radiolabeled with beta- or alpha-emitters such as, 131 I, 32 P, and radioisotopes of astatine (e.g., 225 At). Unlike Auger electron emitters, these radioisotopes are radiotoxic even when outside of the cell. Such isotopes would allow for the irradiation of neighboring cells, i.e., a bystander effect, which is beneficial, particularly if AR expression is not uniform. IUdR is, for the most part, taken up selectively by dividing cancerous cells located within nondividing cells and is indefinitely retained following DNA incorporation. Nondividing cells will not incorporate radiolabeled IUdR into their DNA and most of the radiolabeled IUdR that is not taken up by cancerous cells will be catabolized/dehalogenated rapidly [t 1/2 of minutes] and thus will not incorporate into the DNA of distant noncancerous dividing cells. Furthermore, since it is a small molecule, radiolabeled IUdR will not induce an antibody response and as such lends itself to repeated injections, continuous infusion, or similar modes of administration.
In order to provide cancer cell specificity and enhanced delivery, the radiolabeled thymidine analogs are conjugated to an AR ligand. Radiolabeled IUdR, for example, is conjugated to the androgen ligand DHT. Importantly, AR is expressed on cells from a variety of cancers, such as 50–90% of breast tumors (Bryan, R. M., et al. (1984) Cancer, 54:2436–2440; Lea, O. A., et al. (1989) Cancer Res., 49:7162–7167; Soreide, J. A., et al. (1992) Eur. J. Surg. Oncol., 18:112–118). DHT, in addition to providing specific targeting of the conjugate to cells expressing AR, has also demonstrated anti-cancer effects in breast cancer experimental models (see, for example, Poulin, R., et al. (1988) Breast Cancer Res. Treat., 12:213–225) and other androgens, such as fluoxymesterone, have produced anti-cancer effects in administration to patients (see, for example, Ingle, J. N., et al. (1991) Cancer, 67:886–891).
Particularly preferred conjugates in accordance with the present invention have the formula
wherein R and R′ are as previously defined.
The term “lower alkyl”, as used herein, refers to a straight or branched chain hydrocarbon group having 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms.
Specific examples of conjugates within the scope of this invention are the following:
Synthetic routes for the preparation of these conjugates are exemplified hereinbelow.
In vitro studies conducted to date with certain of the specific conjugates described above have produced several notable results. First, coupling of DHT to 125 IUdR produces cell killing agents which specifically target AR. Second, excess DHT competes with the DHT-containing conjugate for binding to AR. Third, uptake of the conjugate by the cell and metabolic processing of the conjugate is dependent on the presence of AR. Furthermore, in vivo studies have shown that certain of the above-described conjugates are bound specifically to the sex hormone binding globulin and are actively transported into cells that express AR and that uptake of 125 IUdR transported to in vivo grown tumors in the form of conjugates with DHT is dependent on the AR-expression and results in the arrest of tumor growth.
Therapeutic preparations comprising the conjugates of this invention may be conveniently formulated for administration with a biologically acceptable vehicle, which may include the patient's own serum or serum fractions. Other suitable vehicles include liposomes and similar injectable suspensions, saline, activated carbon absorbents, and solutions containing cyclodextrins such as alphadex and betadex. Additionally, IUdR compounds may be derivatized, e.g. by esterification of available hydroxyl groups, with long chain fatty acids to increase the circulation half-life of the compounds. The concentration for diagnostic uses of the conjugate in the chosen vehicle should normally be from about 0.1 mCi/mL to about 10 mCi/mL. The concentration for therapeutic uses of the conjugate in the chosen vehicle should normally be from about 1 mCi/mL to about 100 mCi/mL. These concentrations may vary depending on whether the method of administration is intravenous, intraperitoneal, or intratumor. In all cases, any substance used in formulating a therapeutic preparation in accordance with this invention should be virus-free, pharmaceutically pure and substantially non-toxic.
If necessary, the action of contaminating micro organisms may be prevented by various anti-bacterial and/or anti-fungal agents, such as parabens, chlorbutinol, phenyl, sorbic acid, thimerosal and the like. It will often be preferable to include in the formulation isotonic agents, for example, glucose or sodium chloride. Additionally, free-radical scavengers and antioxidants such as ascorbic acid and the like may be employed to allow for a longer storage of the radioactive drug.
As used herein, the term “biologically acceptable vehicle” is intended to include any and all solvents, dispersion media and the like which may be appropriate for the desired route of administration of the conjugates described herein, either as such, or in the form of a pharmaceutical preparation, as described above. Except insofar as any conventional vehicle is incompatible with the conjugates of this invention, its use in formulating pharmaceutical preparations including such conjugates is contemplated. It is noted in this regard that administration of the conjugates of this invention with any substance that competes with the conjugate for AR binding is to be avoided.
The conjugates described herein may be administered parenterally to a patient, either as such or in combination with a biologically acceptable vehicle, as noted above, by conventional procedures. The preferred modes of administration are intravenous and intraperitoneal. For therapeutic applications, the conjugate will typically be administered at a dose that provides from about 1 mCi (37 MBq)-20 mCi (740 MBq) of radioactivity per 24 hours. The amount of the conjugate administered for diagnosis will generally be an amount sufficient to provide between 0.1 mCi and 10 mCi of radioactivity. For the registration of AR expression, the imaging can commence immediately after the administration. To detect DNA uptake, imaging may begin 1 hour after administration. Notably, with longer lived radioisotopes, imaging can occur at least daily for 7 days or longer to assess the tumor growth kinetics. The determination of an appropriate dose of the conjugate, either therapeutic or diagnostic, for a particular patient will, of course, be determined based on the type and stage of the patient's cancer and the judgment of the attending medical oncologist or radiologist, as the case may be.
As used herein, the term “patient” includes both humans and animals.
The targeted delivery of radio nuclides to cancer cells in the manner described herein produces strong cytotoxic activity, in that the radionuclide is introduced into the DNA of the multiplying cells, where it induces DNA strand breaks in the double helix. Moreover, by delivering radiolabeled agents to a specific site and relying on mechanisms operational at the site of delivery to release the radiolabeled agent, the usual in vivo degredation pathways are by-passed, bioavailability of the radiolabeled agent is improved and more tumor cells are exposed to the cell killing effect of the radiation as they enter into the S phase.
The following examples describe the synthesis of the aforementioned conjugates 1–5 of the present invention, as well as biological testing of certain of the conjugates. These examples are provided for illustrative purposes only and are not intended to limit the scope of the invention in anyway.
EXAMPLE I
Synthesis of 125 IUdR-3′-succinyl-DHT Conjugate (Scheme 1)
A. Preparation of DHT Half Ester of Succinic Acid
Succinic acid anhydride (2 g, 20 mmol) and DHT (2 g, 6.9 mmol) were dissolved in anhydrous pyridine and 80 mg of 4-dimethylaminopyridine (DMAP) was added. The reaction flask was placed on a rotatory evaporator and approximately 20 mL of pyridine was evaporated under reduced pressure at 50° C. The reaction mixture was then stirred for 1 h at room temperature and ice-water was added (50 mL). The mixture was extracted with ethyl acetate (2×50 mL), washed with 5% citric acid, water and brine. The ethyl acetate layer was dried over anhydrous MgSO 4 . The solvent was evaporated to dryness and an oily residue was treated with ethyl acetate/hexanes mixture to produce white precipitate of the crude DHT half-ester of succinic acid. The end product was collected by filtration and dried in vacuo. The purification of the DHT half-ester of succinic acid was accomplished on a silica gel column with dichloromethane/methanol mixture (10:0.4; v/v) as an eluant to give 2.12 g (78% yield) of the pure half ester.
B. Preparation of 5′-Dimethoxytrityl- 125 IUdR
Dimethoxytrityl chloride (4 g, 11.3 mmol) is added in two portions into a stirred solution of 5-iodo-2′-deoxyuridine (4 g, 11.4 mmol; IUdR) in 50 mL anhydrous pyridine at room temperature. The mixture is stirred overnight. Pyridine is evaporated to dryness and an oily residue is dissolved in 100 mL ethyl acetate, washed with water, 10% citric acid, aqueous saturated sodium bicarbonate solution, and saline. The washed organic layer is dried over MgSO 4 . Ethyl acetate is evaporated to dryness giving a crude DMT-IUdR in the from of a glass-like residue, which is redissolved in ethyl acetate/ethyl ether mixture, filtered and allowed to crystallize at 4° C. overnight. The crystalline, pure DMT-IUdR is collected by filtration. The volume of the filtrate is reduced under vacuum and a silica gel column is used to purify the remaining DMT-IUdR using dichloromethane/methanol (10:0.5; v/v) as a column solvent.
C. Conjugation Reaction and Deprotection
As shown in Scheme 1 below, purified DMT-IUdR (4 g, 6.01 mmol) is dissolved in 3 mL freshly distilled from CaH 2 anhydrous dichloromethane and the DHT half-ester of succinic acid, prepared a previously described, (2.35 g, 6.0 mmol) is added. To this mixture dicyclohexylcarbodiimide (1.26 g, 6.2 mmol; DCC) is added in the presence of 80 mg of 4-dimethylaminopyridine (DMAP). The mixture was stirred at room temperature and the reaction progress was monitored on TLC. When the esterification was complete, the reaction mixture was diluted with ethyl ether (10 mL) and filtered to remove dicyclohexylurea (DCU). The filtrate was washed with water, citric acid and brine and was dried over MgSO 4 . The residue of crude 5′-DMT-protected 6 obtained after evaporation of the solvent was purified on a silica gel column using ethyl acetate/hexanes (3:2; v/v) as a solvent. The yield of 5′-DMT-protected 6 was 3.1 g (50%). The 5′-DMT-protected 6 (3 g) was dissolved in 25 mL of 2-propanol and 1 mL of 90% CF 3 COOH (TFA) was added. After approximately 4 hours at room temperature, TLC indicated that 100% of the DMT protection was removed to generate 5′-deprotected derivative 6. After evaporation of the solvent, the residue was treated with 5 mL water and evaporated again to remove the majority of TFA. The glassy residue was dissolved in dichloromethane and dried over MgSO 4 . The crude product was purified on a silica gel column with ethyl acetate/hexanes (15:10; v/v) as a solvent to give 2.8 g (82%) of pure conjugate 6. The deprotection of 5′-DMT derivative 6 with trifluoroacetic acid can also be conducted in tert-butanol as a solvent.
D. Preparation of Stannyl Derivatives and Radiolabeling Procedure
The preparation of the 5-trialkylstannyl-derivatives (7) is accomplished as described in U.S. Pat. No. 5,468,853 to Baranowska-Kortylewicz which is commonly owned with its present application. The radiolabeling is also accomplished using procedures described in U.S. Pat. No. 5,468,853. The radioisotopes that can be utilized in this protocol include radiohalides such as radioiodine, radiobromine, and radioastatine. The reaction can be conducted with radiochlorine, but not as efficiently, and it does not work for radiofluorine. Suitable oxidants include: iodogen, chloromine-T, N-chlorosuccinimide, hydrogen peroxide, tert-butyl hydroperoxide (T-HYDRO solution; 70% wt in water) and cerium ammonium nitrite.
The conjugate obtained by this synthesis is relatively hydrophobic but still soluble in aqueous media at “no-carrier-added” radioactivity levels. The release of 125 IUdR from the succinate ester appears to be very effective, both in vitro in cell culture and in vivo in tumor bearing animals. The half-life in vivo is short and may be detrimental to the delivery of therapeutic doses to tumor. On the other hand, because the half-life is short, repeated injections should be possible without a large radioactive burden in normal tissue.
EXAMPLE II
Synthesis of 5′-monophosphate- 125 IUdR-3′-succinyl-DHT Conjugate (Schemes 2 and 3)
A. Phosphorylation Reaction
IUdR (1.5 g, 4.25 mmol) was dissolved in 7 mL of DMF/THF mixture (3:4; v/v) under strictly anhydrous conditions. After cooling to 0° C., 1H-tetrazole (1.2 g, 17.1 mmol) and di-tert-butyl diisopropylphosphoramidite (1.65 mL, 5.1 mmol) were added. The mixture was stirred at 0–4° C. for 72 h. Tert-Butyl hydroperoxide (4.6 mL) was added at −80° C. and the mixture was allowed to slowly warm up to room temperature. A 5% solution of NaHSO 3 (10 mL) was added and the whole mixture was evaporated to dryness. The residue was extracted with dichloromethane (2×50 mL) and the organic layer dried with MgSO 4 . A mixture of all possible phosphorylated derivatives of IUdR was obtained, i.e., 3′-monosubstituted, 5′-monosubstituted and 3′,5′-disubstituted. Separation of the desired 5′-isomer was accomplished on a silica gel column with chloroform/methanol (10:0.6; v/v) as a solvent. The desired pure 5′-monosubstituted derivative (8) was isolated in 52% yield. The final purification was accomplished by crystallization from ethyl ether to give white solid, mp. 121–123° C.
B. Conjugation Reaction and Radiolabeling
The DHT half-ester of succinic acid, prepared as described in Example 1 above, (0.77 g, 1.46 mmol) was dissolved in 10 mL of anhydrous dichloromethane. Dicyclohexylcarbodiimide (DCC; 0.32 g, 1.5 mmol) was added followed by phosphorylated IUdR (8) (0.8 g, 1.46 mmol) and DMAP (70 mg). The reaction mixture was stirred at room temperature until starting materials disappeared as determined by TLC. The solvent was evaporated under vacuum and replaced with ethyl acetate/hexanes mixture (3:2; v/v). The precipitated DCU was removed by filtration and the filtrate was washed with citric acid and water. The organic layer was dried under MgSO 4 and evaporated again. The purification of the resulting conjugate 9 was done on a silica gel column using chloroform/methanol mixture (10:0.6; v/v) as a solvent. The final pure conjugate was obtained in 49% yield (0.66 g).
The stannyl derivative was prepared and radiolabeling was carried out in the same general manner as in Example 1, above. Removal of the protecting t-butyl group was effected by a breif exposure of the 125I-labeled derivative to the HPLC solvent which is typically 0.05% to 0.5% trichloroacetic acid (TCA) in acetonitrile at room temperature.
An alternative approach to the synthesis of conjugate 2 is shown in Scheme 3, in which the conjugation reaction is carried out prior to phosphorylation. However, Scheme 2 has been found to produce the desired conjugate in higher yield.
Conjugate 2 is the most hydrophilic of the conjugates described herein (two negative charges on the monophosphate group). It cannot cross the cell membrane by itself, i.e., it requires the active transport mechanism from the systemic circulation into the tumor cells with the aid of sex hormone binding globulin.
EXAMPLE III
Synthesis of 5′-[ 125 I]iodo-2′-deoxy-5′-monophosphate-O-methyl-O-(mono-dihydrotestosterone) (Scheme 4)
A. Preparation of N,N-diisopropylmethylphoshoramidate of DHT
Dihydrotestosterone (5α-androstan-17β-ol-3′-one; 2 g, 6.9 mmol) was dissolved in 30 mL of anhydrous THF under nitrogen. N,N-Diisopropylethylamine (DEPA; 1.78 g, 13.8 mmol) and DMAP (20 mg, 0.13 mmol) were added. A stirred mixture was cooled to 0° C. and N,N-diisopropylmethylphosphoamidic chloride (2.05 g, 10.33 mmol) was added neat in five 0.5-mL portions. Stirring was continued at 0° C. for 30 min. The precipitate was filtered off and the filtrate was evaporated to dryness under vacuum. A crude product was purified on a silica gel column using dichloromethane/ethyl acetate/triethylamine (10/10/0.05; v/v) as a solvent. Only partial purification was achieved and the material obtained from the column was used in the following step of the synthesis.
B. Preparation of 5-Iodo-2′Deoxyuridine-5′-Monomethylphosphate-3′-Succinyl DHT
A solution of the freshly prepared N,N-diisopropylmethylphosphoramidate of DHT (1.55 g, 3.4 mmol) in anhydrous THF (20 mL) was cooled to 0° C. and 1H-tetrazole (1.4 g, 20 mmol) was added followed by IUdR (1.1 g, 3.1 mmol) dissolved in 5 mL anhydrous DMF. The mixture was allowed to react overnight at 0°–2° C. Tert-Butyl hydroperoxide (4 mL, 70% w solution in water) was added at −10° C. The mixture was allowed to slowly reach room temperature and after 1 hour of stirring at room temperature the solvent was evaporated to dryness under vacuum. The semi-solid residue was extracted with dichloromethane (2×50 mL) and washed with 5% NaHSO 3 and water. During the extraction unreacted IUdR was separated and removed by filtration. The filtrate was dried over MgSO 4 and again evaporated to dryness. The residue was analyzed on TLC plate and revealed the presence of two UV-positive spots along with a small residual spot corresponding to unreacted IUdR. The two UV-positive components were separated on a silica gel column using dichloromethane/methanol mixture (10:0.6; v/v) as a solvent. The major component (TLC R f =0.65) was identified as a 5′-regioisomer (12) and was obtained after the column chromatography in 63% yield (1.23 g).
The stannyl derivative (14) was prepared and radiolabeling was carried out in the same general manner as in Example 1, above.
Alternatively, the method of scheme 4 can be performed using the N,N-diisopropylmethylphosphoramidate of DHT, and following the same procedure described above except that the methyl group is hydrolyzed prior to the stannylation reaction. The final reaction product of scheme 4 with this modification is 5′-[ 125 I]iodo-2′-deoxy-5′-monophosphate-O-(mono-dihydrotestosterone) (4A).
Conjugates 4 and 4A possess interesting characterisitics in that the negative charge on the monophosphate—either already present as in conjugate 3 or generated after administration by circulating carboxylases—will prevent the uptake of this drug via passive diffusion (charged molecules cannot readily cross the cell membrane, they require the active transport mechanism to be able to enter cancer cells), thus improving the selectivity. This is very similar to conjugate 2, but the DHT on phosphate is more stable compared to succinate esters.
EXAMPLE IV
Synthesis of 5′-[ 125 I]iodo-2′-deoxy-5′-monphosphate-O-(bis-dihydrotestosterone) (Scheme 5)
A. Preparation of N,N-diisopropylphosphoramidite (DHT) 2
Diisopropylphosphoramidous dichloride (0.65 mL, 3.45 mmol) was added to a stirred solution of DHT (2 g, 6.9 mmol) containing 1.5 mL (8.5 mmol) of DEPA and 65 mg of DMAP in 50 mL anhydrous THF at 0° C. Copious amounts of white precipitate were formed. The stirring was continued for 2 hours at room temperature. The precipitate was removed by filtration and the filtrate was evaporated to dryness. The crude product was partially purified on a silica gel column using dichloromethane/ethyl acetate/triethylamine (10/5/0.05; v/v) as a solvent. The partially purified (approximately 95% pure) N,N-diisopropylphophoramidite (DHT) 2 was used in the following reaction.
B. Preparation of 5-Iodo-2′Deoxyuridine-5′-Mono-O-(bis-dihydrotestosterone)phosphate
A solution of freshly prepared N,N-diisopropylphosphoramidite of DHT (2.1 g, 2.92 mmol) in 20 mL of anhydrous THF was stirred at 0° C. while 1H-tetrazole (1 g, 14.2 mmol) followed by IUdR (2 g, 5.65 mmol) as a solution in 5 mL of anhydrous DMF were added sequentially. This reaction mixture was stirred at 0°–2° C. overnight. After cooling to −10° C., 4 mL of tert-butyl hydroperoxide was added and with constant stirring. The mixture was allowed to reach room temperature over a period of 30 min. The white precipitate was filtered off and the filtrate was treated with 5% NaHSO 3 (10 mL). The organic layer was evaporated to dryness and the residue was kept under high vacuum for 1 hour. The residue was extracted with dichloromethane (2×50 mL) and the combined extracts were washed with water, NaHCO 3 and dried over MgSO 4 . The solvent was evaporated to dryness and the residue containing two UV-positive components (R f 0.58 and R f 0.40 on TLC) were separated and purified on a silica gel column using dichloromethane/methanol (10:0.7; v/v) as a solvent to give 0.9 g (R f 0.58) and 0.15 g (R f 0.40) of the two regioisomers. The faster isomer (R f 0.58) was identified as pure conjugate 13.
The stannyl derivative 15 was prepared and radiolabeling was carried out in the same general manner as in Example 1, above.
Conjugate 5 is the most hydrophobic of all the conjugates described herein. It may be best suited for local/regional administration (e.g., intraperitoneal in the case of ovarian cancer) with a slow diffusion from the site of injection.
EXAMPLE V
Binding of 125 IUdR-DHT to OVCAR-3 Cells In Vitro
To generate a Scatchard plot for the binding of 125 IUdR-DHT to OVCAR-3 cells, OVCAR-3 cells were thawed from a stock or freshly harvested by a lavage of the peritoneal cavity of athymic mice bearing intraperitoneal ascites OVCAR-3 tumors. The cells were twice washed with full media (RPMI 1640 medium with 2 mM L-glutamine adjusted to contain 1.5 g/L sodium bicarbonate, 4.5 g/L glucose, 10 mM HEPES, and 1.0 mM sodium pyruvate and supplemented with 0.01 mg/ml bovine insulin, 80%; fetal bovine serum, 20%). The cells were spun at 450 rpm for 10 minutes to collect a cell pellet and were then resuspended in full media to achieve approximately 5×10 6 cells/mL. The cells were counted and their viability was determined by Trypan Blue staining. “Cold” dihydrotestosterone (DHT) was dissolved in 95% ethanol to create a stock solution of 5 μg/mL. Similarly, 95% ethanol was added to 125 IUdR-DHT to produce 250,000 cpm/100 μL. Forty samples were prepared in plastic tubes as set forth in Table 1.
TABLE 1 Tube 125 IUdR-DHT “cold” DHT 95% EtOH number cells cpm (μL) ug (μL) μL 1 a, b 5 × 10 6 250,000 (100) 5 (10) 0 2 a, b 5 × 10 6 200,000 (80) 5 (10) 20 3 a, b 5 × 10 6 150,000 (60) 5 (10) 40 4 a, b 5 × 10 6 125,000 (50) 5 (10) 50 5 a, b 5 × 10 6 100,000 (40) 5 (10) 60 6 a, b 5 × 10 6 75,000 (30) 5 (10) 70 7 a, b 5 × 10 6 50,000 (20) 5 (10) 80 8 a, b 5 × 10 6 25,000 (10) 5 (10) 90 9 a, b 5 × 10 6 12,500 (5) 5 (10) 95 10 a, b 5 × 10 6 0 (0) 5 (10) 100 11 a, b 5 × 10 6 250,000 (100) 0 10 12 a, b 5 × 10 6 200,000 (80) 0 30 13 a, b 5 × 10 6 150,000 (60) 0 50 14 a, b 5 × 10 6 125,000 (50) 0 60 15 a, b 5 × 10 6 100,000 (40) 0 70 16 a, b 5 × 10 6 75,000 (30) 0 80 17 a, b 5 × 10 6 50,000 (20) 0 90 18 a, b 5 × 10 6 25,000 (10) 0 100 19 a, b 5 × 10 6 12,500 (5) 0 105 20 a, b 5 × 10 6 0 (0) 0 110
The tubes were capped and gently vortexed. The “total applied” counts were then determined in a gamma counter. The samples were then incubated at 0–4° C. with shaking for 14–16 hours. The cells were centrifuged at 1,000 rpm for 15 minutes at 4° C. to generate a cell pellet. A known volume of the supernatant from the centrifugation was transfered to new plastic tubes and counted in a gamma counter to determine the “free” counts. The cell pellet with the remainder of the supernatant was then counted in the gamma counter. “Bound” counts were then determined by subtracting counts associated with the supernatant from the remaining counts. Plots of this data can be found in FIG. 1 . The data show a single type of binding sites with a high affinity for 125 IUdR-DHT. Use of the excess DHT revealed that the high affinity seen is due to the DHT portion of the drug and thus dictated by the presence of AR.
To determine the strength of the interaction of 125 IUdR-DHT with the cells, the cells were then washed with ice-cold phosphate buffered saline (PBS) and gently centrifuged. Again, a known volume of the supernatant was removed and both the supernatant and pellet were counted in the gamma counter.
For general binding assays, OVCAR-3 cells were harvested by a lavage of the peritoneal cavity of athymic mice bearing intraperitoneal ascites OVCAR-3 tumors. Cells were washed with Hank's balanced salt solution (HBBS), resuspended in RPMI 1640 medium without serum and used in a binding assay.
Alternatively, cells harvested from the intraperitoneal ascites tumors were plated in tissue culture flasks (T25) at 1×10 6 cells/mL in RPMI 1640 with added penicillin, streptomycin, L-glutamine and 10% fetal bovine serum. The cells were allowed to reach about 70% confluency and the serum-containing medium was aspirated and replaced with serum-free medium (SFM). The cells were allowed to remain in SFM for 24 hours. After 24 hours, the medium was aspirated and SFM containing 10 nM dihydrotestosterone (DHT) was added to three flasks. The volume of added SFM was carefully measured to assure that each flask received an identical volume of SFM. To the another three flasks an identical volume of SFM without DHT was added. The cells were incubated overnight. The medium was removed from all flasks and the cells were washed with 40 mM HEPES supplemented with 0.1% bovine serum albumin (0.1 g BSA in 100 mL HEPES), pH 7.4. 125 IUdR-DHT derivative was dissolved in HEPES/BSA buffer to produce a final concentration of about 50,000 cpm/mL. An identical volume of 125 I-DHT-containing buffer was added to all six flasks and incubated for 5 hours at 4° C. The medium was aspirated and 1 mL aliquots were counted in a gamma counter to determine cpm/mL after incubation. Cells were washed two times with ice-cold PBS containing 0.1% BSA. The washes were combined, the total volume measured, and 1 mL aliquots were counted in a gamma-counter. To the cells, 5 mL of 1 M NaOH was added and incubated for two hours. The NaOH wash was collected and 1-mL aliquots were counted in a gamma-counter. One mL PBS was added to the remaining cells and the cells were scraped and transferred into gamma-counter tubes to determine cpm/mL. This procedure may be employed to determine competitive binding wherein the amount of cpm in the NaOH-treated cell pellet in the absence of “cold” DHT is the “total bound” and the amount of cpm in NaOH-treated cells that were incubated with “cold” DHT can yield the amount of nonspecific binding. This method works well with cells that grow as monolayers such as PC3, LNCaP, and DU-145 cells.
EXAMPLE VI
Stability of 125 IUdR
OVCAR-3 cells in full growth medium (RPMI 1640 medium with 2 mM L-glutamine adjusted to contain 1.5 g/L sodium bicarbonate, 4.5 g/L glucose, 10 mM HEPES, and 1.0 mM sodium pyruvate and supplemented with 0.01 mg/ml bovine insulin, 80%; fetal bovine serum, 20%) at 1×10 6 cells per flask were plated onto three Petri dishes and allowed to attach for 24 hours. As a control, one dish without cells was subjected to the same treatments. After 24 hours, the cells were trypsinized from one dish to determine cell number and viability. The media was then aspirated from the remaining dishes, including the control, and replaced with 1 mL of fresh media. 0.1 mCi of 125 IUdR-DHT in 0.10 mL of ethanol was added to all of the dishes. The dishes were incubated at 37° C. At 0, 5, 15, 30, 60, 120, 180, and 240 minutes, 10 μL of media was removed from each of the dishes of which 2 μL was added to a silica gel TLC plate. Additionally, 2 μL was added to glass gamma counter tubes as standards. The TLC plates were run with a 3:1 mixture of ethyl acetate and hexane (v/v). When the solvent front approached the end of the plate, the plate was removed from the solvent, dried, and cut into strips. The standards and the strips were then counted. The percent recovered 125 IUdR-DHT was calculated as a ratio of the intact 125 IUdR-DHT at a given timepoint divided by the intact 125 IUdR-DHT at the 0 minute timepoint (see FIG. 2A ). Similar calculations were used to determine the kinetics of the appearance of 125 IUdR in the medium, which was determined to occur at a rate of 8.5%/hour ( FIG. 2B ). This rate is in comparison to the disappearance of 125 IUdR-DHT from the media at a rate of 16%/hour. Notably, 125 IUdR is freely diffusible from cells and therefore only a fraction of 125 IUdR-DHT hydrolyzed in cells is used for DNA synthesis. The inclusion of a negatively-charged monophosphate assists in the retention of these compounds in the cell.
EXAMPLE VII
Binding of 5′-MP- 125 IUdR-DHT to Sex Hormone Binding Globulin
Typically, the testosterone or DHT signaling in AR-positive cells involves sex hormone binding globulin (SHBG). Human SHBG-DHT complexes interact with plasma membranes of several sex steroid-dependent cells and tissues. This interaction involves the binding of SHBG to a specific membrane protein receptor, which promotes its cellular internalization. The next step entails binding to AR and conformational changes in AR. AR is subsequently translocated to the nucleus where it dimerizes and binds DNA. The overall process allows for the intracellular delivery of the 125 IUdR drugs only to cells expressing AR.
To assay the binding of 5′-MP- 125 IUdR-3′-DHT to SHBG, a 0.1 mg/mL solution of SHBG in 0.1 M Tris buffer, pH 7.6 containing 0.1% bovine serum albumin was prepared as a stock solution. Additionally, a solution of 0.1 mCi/mL 5′-MP- 125 IUdR-3′-DHT in 50% ethanol and a solution of 0.05 mg/mL DHT in 50% ethanol were prepared. Twenty samples of were prepared as set forth in Table 2 with the 5′-MP- 125 IUdR-3′-DHT being added last.
TABLE 2 SHBG DHT 5′-MP- 125 IUdR- Tris buff 50% EtOH tube mL mL 3′-DHT (mL) mL mL 1 0.2 0.000 0.01 0.590 0 2 0.2 0.000 0.01 0.590 0 3 0.2 0.002 0.01 0.588 0 4 0.2 0.002 0.01 0.588 0 5 0.2 0.004 0.01 0.586 0 6 0.2 0.004 0.01 0.586 0 7 0.2 0.008 0.01 0.582 0 8 0.2 0.008 0.01 0.582 0 9 0.2 0.016 0.01 0.574 0 10 0.2 0.016 0.01 0.574 0 11 0.2 0.032 0.01 0.558 0 12 0.2 0.032 0.01 0.558 0 13 0.2 0.064 0.01 0.526 0 14 0.2 0.064 0.01 0.526 0 15 0.2 0 0.01 0.526 0.064 16 0.2 0 0.01 0.526 0.064 17 0.2 0 0.01 0.574 0.016 18 0.2 0 0.01 0.574 0.016 19 0.2 0 0.01 0.586 0.004 20 0.2 0 0.01 0.586 0.004
The tubes were then vortexed for about 30 seconds and incubated for 10 minutes in a water bath at 37° C. The samples were then incubated at 0–4° C. for 3 hours. 0.1 mL aliquots were removed from the samples and counted in a gamma counter. To each tube, 0.4 mL of ice-cold charcoal-dextran solution was added and the tubes were incubated on ice for 15 minutes. The samples were then centrifuged at 4° C. for 20 minutes at 1,000 rpm. 0.5 ml aliquots were taken for gamma-counting and the residue was also counted. Selected samples were analyzed by size-exclusion HPLC (tandem TSK2000 and TSK3000 size exclusion columns (TosoHaas; Montgomeryville, Pa.) with a guard column using PBS, pH7.2 as the eluant). As seen in FIG. 3 , SHBG specifically bound 5′-MP- 125 IUdR-3′-DHT and this interaction was competed away with “cold” DHT.
EXAMPLE VIII
In Vivo Effects of 5′-MP- 125 IUdR-3′-DHT
Athymic mice bearing intraperitoneal OVCAR-3 tumors were treated with 0.05 mCi (1.4 kBq) 5′-MP- 125 IUdR-3′-DHT intraperitoneally. Tumor cells were recovered by peritoneal lavage from the mice at 0, 24, 48, and 72 hours after 5′-MP- 125 IUdR-3′-DHT administration. The cells were washed with phosphate buffered saline. The cells were subsequently pelleted and counted in a gamma counter to determine tumor uptake (n=5; FIG. 4 ). To determine the amount of DNA-bound 125 IUdR, the cells were fractionated using a Wako kit (Wako Cemicals USA, Inc., Richmond, Va.) or, alternatively, with a NE-PREP nuclear and cyoplasmic extraction kit (Pierce, Rockford, Ill.) per the manufacturer's instruction. The distribution of radioactivity in the cytoplasm and DNA were measured and normalized to tumor size ( FIG. 4 ).
With regard to 125 IUdR-3′-DHT, the biodistribution of the reagent (0.001–0.010 mCi/mouse; 0.027–0.27 kBq/mouse) in athymic mice bearing AR-expressing OVCAR-3 tumors is seen in Table 3. Additionally, the efficacy of the reagent against the intraperitoneal OVCAR-3 tumors after 6 fractionated doses (0.1 mCi/dose/mouse; 2.7 kBq/dose/mouse) is seen in Table 4. The tumor uptake of 125 IUdR-3′-DHT and the incorporation into DNA over time is shown in FIG. 5 .
TABLE 3
Percent injected dose per gram tissue
average of n = 10 (standard deviation)
1.5 h
24 h
48 h
72 h
Blood
29.61
0.25
0.30
0.17
(5.22)
(0.08)
(0.15)
(0.00)
OVCAR-3 tumor
20.70
5.66
5.41
3.54
(IP)
(0.95)
(0.37)
(0.73)
(0.27)
solid OVCAR-3*
12.94
0.67
0.28
0.24
(1.56)
(0.46)
(0.01)
(0.01)
Brain
1.91
0.03
0.05
0.04
(0.39)
(0.01)
(0.01)
(0.00)
Kidney
17.67
0.20
0.18
0.22
(3.18)
(0.02)
(0.01)
(0.01)
Spleen
15.60
0.59
0.44
0.59
(2.82)
(0.02)
(0.04)
(0.11)
Liver
11.07
0.24
0.32
0.33
(2.92)
(0.04)
(0.06)
(0.03)
Uterus
11.43
0.54
0.66
0.97
(0.42)
(0.21)
(0.33)
(0.34)
*on average approximately 2 mice in each group developed solid IP tumors
TABLE 4 125 IUdR-DHT with excess “cold” DHT to block uptake of the Shamtreatment 125 IUdR-DHT radioactive drug (control mice) mean tumor 0.304 ± 0.320* 0.635 ± 0.332 1.955 ± 1.109 burden (g) median tumor 0.244 0.533 1.864 size (g) range (g) 0.012–0.781 0.192–1.238 0.515–3.402 tumor growth −670% −230% 0% reduction *average (n = 10) and standard deviation
Notably, the stability of 125 IUdR-3′DHT in the presence of OVCAR-3 cells showed that the emergence of “free” 125 IUdR in the growth medium requires interaction of the drugs with specific cells. This experiment also showed that the first step in the enzymatic hydrolysis of the reagent appears to be the removal of the DHT moiety. This allows at least a partial retention of the negatively charged succinate inside the cell where the next hydrolytic step frees 125 IUdR to be taken up by DNA.
A number of literature and patent references are cited in the foregoing specification in order to more fully describe the state of the art to which this invention pertains. The entire disclosure of each of these citations is incorporated by reference herein.
While certain embodiments of the present invention have been described and/or specifically exemplified above, various other embodiments will be apparent to those skilled in the art from the foregoing disclosure. The present invention is, therefore, not limited to such embodiments, but is capable of considerable variation and modification without departing from the scope of the following claims. | Radiolabeled conjugates are disclosed which have a component that is effective to target tumor cells, which cells selectively take up and degrade the conjugate, thereby delivering to the tumor cell nucleus a radioisotope capable of being incorporated into the nuclear material, so as to produce a cytotoxic effect and/or to render the cell detectable by radioimaging. | 0 |
FIELD OF THE INVENTION
This invention is related to a method of making a modified silica filler in which silica is contacted with a blend or mixture of a diorganodihalosilane and a tetrahalosilane in a weight ratio of 1:0.1 to 1:2, respectively.
BACKGROUND OF THE INVENTION
This is an improvement in methods of modifying silica fillers, as described for example, in U.S. Pat. No. 6,051,672 (Apr. 18, 2000), assigned to the same assignee as the present invention. While the '672 patent contains a general formula (1) which broadly interpreted includes tetrahalosilanes, (i) no particular tetrahalosilane compounds are disclosed in the '672 patent, (ii) the '672 patent does not describe any particular mixture or blend of tetrahalosilane compounds and diorganodihalosilane compound as being any more effective than any other blend, (iii) nor does the '672 patent teach any particular ratio of these silane compounds as being necessary to achieve new and unexpected results, i.e., the ability to deposit more siloxane on silica, vis a viz, improved its hydrophobicity.
Furthermore, it is generally recognized in the art that treating agents used to impart hydrophobicity to surfaces should contain organic or hydrocarbon groups characteristic of fats, oils, and waxes such as alkyl groups. However, since tetrahalosilanes such as silicon tetrachloride SiCl 4 contain no organic or hydrocarbon groups in their molecule, it was highly unexpected that they would possess this functional utility.
SUMMARY OF THE INVENTION
The invention is directed to a method of making modified silica fillers in which silica is contacted with a blend or mixture of organosilicon compounds. In particular, it is directed to an improvement in treating silica with blends or mixtures of diorganodihalosilanes and tetrahalosilanes, in weight ratios of 1:0.1 to 1:2, respectively.
Preferably, the weight ratio is 1:0.3 to 1:1, most preferably 1:0.5. Similarly, the blend or mixture is preferably a dialkyldichlorosilane and a tetrahalosilane such as silicon tetrachloride, silicon tetrabromide, and silicon tetraiodide, most preferably dimethyldichlorosilane and silicon tetrachloride. In some additional embodiments, the blend or mixture may also comprise compositions containing (i) dimethyldichlorosilane, (ii) silicon tetrachloride, and (iii) mercaptopropyltriethoxysilane.
These and other features of the invention will become apparent from a consideration of the detailed description.
DETAILED DESCRIPTION OF THE INVENTION
The silica used to make the modified silica fillers according to this invention are the colloidal or precipitated silicas of the type used to formulate polymeric compositions such as rubber, particularly those rubber compositions used in the manufacture of vehicle tires for improving the mechanical properties of tire rubber. Such silicas are described in detail in the '672 patent, and in U.S. Pat. No. 5,908,660 (Jun. 1, 1999), to which reference may be had and which are considered incorporated herein by reference.
Mineral fillers such as silica, having a small particle size and a large surface area, are capable of increasing the tensile strength of rubber compounds, and therefore are useful as a reinforcing material for rubber; particularly when the mineral surfaces of the filler are converted to hydrophobic low energy surfaces. Typically, this is carried out using methylchlorosilanes which react with the surface water of mineral surfaces or the water present in a reaction, i.e., hydrolysis and condensation of silanols, liberating hydrochloric acid and concurrently depositing a very thin film of methylpolysiloxanes with low critical surface tensions not wetted by water. A very simplified representation is ≡Si—Cl+H 2 O→≡SiOH+HCl→≡Si—O—Si≡.
Among some of the other reasons it may be desirable to impart hydrophobicity to silica surfaces, is that it renders them easily dispersible in organic systems such as defoamers, and in food, dairy, and vegetable processing. In other applications, silica particles rendered sufficiently hydrophobic can be held at oil-water interfaces. Surfaces of oxide minerals modified with monolayers of organofunctional silanes to render such surfaces hydrophobic make them useful in oil recovery, ore flotation, pigment dispersion, and for surface modification of metals. These water repellent, low energy surfaces are useful in water resistant treatments for masonry, electrical insulation, packing for chromatography, and in non-caking fire extinguishers. Ceramic insulators treated in this fashion are capable of maintaining high electrical resistivity under humid conditions. Forming an insoluble water resistant methylpolysiloxane film on a surface protects brick, mortar, sandstone, and concrete from spalling, cracking, and efforescence.
When silicone rubbers are reinforced with untreated silicas, reactions can take place causing the mixture to become tough and nervy, making it difficult to further process the mixture unless processing is performed immediately after the mixture is prepared. Reactions known as structuring and crepe aging can be prevented by treating silica surfaces with materials capable of reacting with hydroxyl radicals present on silica surfaces. While many methods have been devised for treating silica as powders and water dispersions to prevent structuring and crepe aging, the present invention provides a simplified avenue for producing treated silicas useful in reinforcing silicone rubbers as well.
The silica treating agents according to the invention are blends of organodichlorosilanes and tetrahalosilanes such as silicon tetrachloride, silicon tetrabromide, and silicon tetraiodide. The organodichlorosilanes may contain alkyl groups, cycloalkyl groups, araalkyl (arylalkyl) groups, alkaryl (alkylaryl) groups, aryl groups, and certain substituted groups which are not reactive with respect to silica surfaces.
Some examples of alkyl groups are methyl, ethyl, propyl, butyl, hexyl, octyl, decyl, dodecyl, octadecyl, and nonadecyl. Some examples of cycloalkyl groups are cyclobutyl and cyclohexyl. Some examples of araalkyl (arylalkyl) groups are benzyl, phenylethyl, and 2-phenylpropyl. Some examples of alkaryl (alkylaryl) groups are tolyl and mesityl. Some examples of aryl groups are phenyl, xenyl, naphthyl, and anthracyl. Some examples of substituted groups which are not reactive with respect to a silica surface are halogenated alkyl groups and aryl groups such as chloromethyl, dichloromethyl, trichloromethyl, 3-chloropropyl, chlorocyclohexyl, chlorophenyl, and dichloroxenyl; alkyl groups containing alkoxy radicals such as methoxy, ethoxy, butoxy, and pentoxy; alkyl groups containing sulfido (—S—), disulfido, or polysulfido radicals; and alkyl groups containing cyano (—C≡N) radicals.
Representative of some organodichlorosilanes and tetrahalosilanes which can be used according to this invention are silicon tetrachloride, silicon tetrabromide, silicon tetraiodide, n-butylmethyldichlorosilane, t-butylmethyldichlorosilane, t-butylphenyldichlorosilane, cyclohexylmethyldichlorosilane, n-decylmethyldichlorosilane, di-n-butyldichlorosilane, di-t-butyldichlorosilane, dicyclohexyldichlorosilane, dicyclopentyldichlorosilane, diethyldichlorosilane, di-n-hexyldichlorosilane, dimesityldichlorosilane, dimethyldichlorosilane, di-n-octyldichlorosilane, di-phenyldichlorosilane, di-(p-tolyl)dichlorosilane, docosylmethyldichlorosilane, dodecylmethyldichlorosilane, ethylmethyldichlorosilane, n-heptylmethyldichlorosilane, hexylmethyldichlorosilane, n-octylmethyldichlorosilane, phenylethyldichlorosilane, phenylmethyldichlorosilane, and p-tolylmethyldichlorosilane.
A general method of making modified silica fillers according to the invention is described below in Example A, although the modified silica fillers can be made by any known and accepted technique, for example, as described in detail in the '660 patent, the '672 patent, and in U.S. Pat. No. 6,384,125 (May 7, 2002). While these patents describe general methods, they fail to describe the features of this invention, i.e., the use of a particular mixture or blend of a diorganodihalosilane and tetrahalosilane compounds in a particular ratio.
When used in rubber compositions for manufacturing vehicle tires, other conventional additives may be used along with the modified silica filler, including other fillers such as carbon black, various oils, plasticizers, accelerators, antioxidants, heat stabilizers, light stabilizers, zone stabilizers, extenders, and coloring pigments.
EXAMPLES
The following examples are set forth in order to illustrate the invention in more detail. The silica slurry used in the examples contained 6.5 percent by weight of silica, and is a commercial product of PPG Industries, Inc., Pittsburgh, Pa. Neutralization was carried out by using a standard solution containing 25 percent by weight of sodium hydroxide, and it was prepared by dissolving 1000 grams of sodium hydroxide pellets in 3000 milliliter of deionized water.
The apparatus used in treating the silica consisted of a 5-liter round-bottom reaction flask, with ball joints, a Teflon® shaft stirring paddle assembly, an overhead electrical stirring motor, and a Type-K thermocouple temperature controller with a flexible heating mantle. The reaction flask was surmounted with a Dean-Stark trap and water cooler condenser with a port for a sealed glass thermocouple well directly submersed into the reaction flask. The third neck of the reaction flask was sealed with a ball-joint cap or an addition funnel. Filtration and washing of treated silica fillers and silica filler cakes was conducted with a 253 mm Coors Porcelain Buchner funnel containing Whatman filter paper. The funnel was mounted on a 4-liter filter flask. A Fisher brand Digital Conductivity Meter was used to measure the conductivity of the filtrate from the washing process. A Mettler Toledo Portable pH\Ion Meter, Model No. MP125 was used to measure pH.
The following procedure, used in Example 2, represents a general procedure which was repeated in Examples 1, 3, and 4. Data for Examples 1-4 is shown in Table 1.
Example A
A General Procedure for Examples 1-4
The reaction flask was charged with 2000 g of silica slurry and 165 g of concentrated sulphuric acid. The slurry was heated to a temperature of 70° C. and the heat was then turned off. At this point, a mixture containing 9.10 g of tetrachlorosilane and 25.5 g of dimethyldichlorosilane was added directly to the reaction flask via a long-stem funnel in rapid fashion over a period of about 2-7 minutes. The treated slurry was then allowed to stir as it cooled to room temperature over a 60-minute period.
To the stirred slurry was added 600 mL of a solution containing 25 percent by weight of sodium hydroxide, in order to adjust the pH in the range of 3.4 to 3.7. The neutralized slurry was transferred to the Buchner funnel and vacuum filtered to removed the aqueous phase. The filter cake was then washed repeatedly with copious amounts of water until the filtrate read less than 100 micro ohms. After allowing it to air-dry overnight, the filter cake was transferred to plastic pails with lids and spray dried as follows.
The air-dried treated silica was re-slurried in deionized water to provide a slurry containing 20-40 percent by weight of the treated silica. The slurry was mixed until all of the solids were broken up. The slurry was then pumped to a Niro Atomizer spray drier at a rate of about 20 ml/minute with an inlet temperature of 260° C. and an outlet temperature of between 120-140° C. The dried and treated silica product was collected and stored in glass jars.
An elemental analysis of the treated silica was conducted by an independent testing laboratory. The results of elemental analyses obtained for treated silica fillers prepared in Examples 1-4 are shown in Table 1. In Table 1, MPTES is 3-mercaptopropyltriethoxysilane HS—CH 2 CH 2 CH 2 —Si(OCH 3 ) 3 and DMDCS is dimethyldichlorosilane.
TABLE 1
Percent Loss Results
Grams
Grams
Grams
Percent Carbon
Rate, Addition
Example
MPTES
DMDCS
SiCl 4
Theory
Actual
% Loss
Minutes
1
25.5
3.28
1.38
58
2
2
25.5
9.1
3.20
2.27
29
2
3
9.1
25.5
9.1
3.76
3.80
0
7
4
9.1
25.5
4.00
2.58
36
7
The new and unexpected results obtained according to the invention, i.e., the deposit of more siloxane, can be appreciated by comparing Examples 1 and 2, which show that the Percent Loss was decreased from 58 percent in Example 1 where only the dichlorosilane was used, to 29 percent in Example 2 where a blend of the dichlorosilane and tetrachlorosilane were employed. As can be seen in Example 3, a further improvement can be obtained by addition of other silanes to the blend. Example 4 shows that other silanes without the tetrahalosilane in the blend or mixture, do not account for improved performance. A comparison of Examples 3 and 4 shows that rate of addition is not a critical factor in improving deposits of siloxanes on silica surfaces.
Thus, the comparison of Example 1 with Example 2 shows a clear improvement. Example 3 shows that inclusion of other additives do not have a deleterious affect; in fact, their addition to the blend of dichlorosilanes and tetrahalosilanes may actually be advantageous in some instances.
Other variations may be made in compounds, compositions, and methods described herein without departing from the essential features of the invention. The embodiments of the invention specifically illustrated herein are exemplary only and not intended as limitations on their scope except as defined in the appended claims. | Modified silica fillers are prepared by contacting silica with blends or mixtures containing diorganodihalosilanes and tetrahalosilanes in weight ratios of 1:0.1 to 1:2, respectively. While dialkyldichlorosilanes and tetrahalosilanes such as dimethyldichlorosilane and silicon tetrachloride, respectively, are most preferred, the blends or mixtures may also comprise compositions containing other silanes such as mercaptopropyltriethoxysilane. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
Co-Pending or Previously Abandoned Patent Applications
[0001] Methods for detection of ultraviolet light reactive alternative cellular energy pigments (ACE pigments). William John Martin Submitted Dec. 24, 2007. Publication number 20090163831 Method of assessing and of activating the alternative cellular energy (ACE) pathway in the therapy of diseases. William John Martin Submitted Jan. 16, 2008. Publication number 20090181467
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[0020] Methods of Transferring Energies to Water, Alcohols and Minerals. Submitted Nov. 25, 2011. Application Ser. No. 13/304,558.
[0021] Weight Change as a Measurement of an Intrinsic Energy Property of Matter. Submitted Dec. 27, 2011. Application Ser. No. 13/340,669
[0022] Weight Change as a Measurement of an Intrinsic Energy Property of Foods and Other Materials, Submitted Jan. 5, 2012.
[0023] Heat as a Method to Enhance the Fluid Activating Ability of Humic Acids, Zeolites and Related Enerceuticals, Submitted May 28, 2014.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0024] Not applicable: No Federal funding was received in support of this patent application.
REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0025] Not Applicable
BACKGROUND OF THE INVENTION
[0026] As detailed in the above-listed co-pending and/or abandoned patent applications, which are herein incorporated by reference, the Applicant has identified an inducible kinetic activity of water, which relates to the water's ability to provide biological benefits beyond that of regular, non-activated water. Water activation is postulated to involve the absorption of an external force tentatively called KELEA (kinetic activity limiting electrostatic attraction). The KELEA activity of water and other fluids can be enhanced using a variety of methods, broadly categorized into two approaches. One approach involves the addition to the water of small amounts of certain unbound dipolar substances. These include humic/fulvic acids, zeolites, various other ceramics, terpenes and many others. The second approach to water activation is to place water into different types of electrical, magnetic and/or other energy fields, including that provided by previously activated fluids. In certain situations, the body itself can produce a water activating energy field, as the Applicant has now shown by including water samples near the participants engaging in Laughing Yoga classes.
[0027] Activation of water can be assessed by the differing dissolving patterns of particles of neutral red dye sprinkled onto the surface of the water. These patterns can range from stationary particles with slowly enlarging concentric rings of dissolved dye (indicative of minimal kinetic activity of the water), to rapid linear movements of the particles in activated water. The linear movements typically have a to-and-fro quality and can lead to long streaks of dissolved dye. In highly activated water, grouping of particles can collectively move as a rapidly rotating, horizontal, cylindrical vortex. While dissolved particles of neutral red dye in regular water, do not yield an ultraviolet (UV) light fluorescent solution, activated water solutions with added neutral red dye will fluoresce upon UV illumination (except if the fluorescence is quenched by particular additional components in the solution). Another useful assay to assess the degree of kinetic activation of water is to measure the rate of weight loss of capped containers of the water. For non-activated water, the weight reduction even over several hours is minimal (<0.1 mg per ml). Activated water will more rapidly lose weight, which occurs primarily by evaporation of highly kinetic molecules. These molecules show the capacity to escape in spite of the screwed cap of the container. The workable threshold of significant activity (weight loss) is >0.5 mg/ml within several hours. Values of >5 mg/ml have been achieved. The increased vaporization is essentially a measure of reduced intermolecular hydrogen bonding of the water molecules and can also be also measured as an increase in vapor pressure within completely sealed containers.
[0028] Activation can be shown with other drinkable fluids, including non-alcoholic and alcoholic beverages. High ethanol content alcoholic beverages have a higher baseline of activity than does water and non-alcoholic beverages, but can be induced to still much higher levels of activity. It has also been noted that a small quantity of activated fluid added to regular fluid will induce activation of the entire fluid in a time dependent manner. This type of progressive activation is typically achieved using 10 fold dilutions. It is similar to the procedure used in preparing, so called, homeopathic formulations. (The Applicant has learned through experimentation that it is preferable to allow for a day or so time delay between dilutions.)
[0029] Unlike, the misleading principle that homeopathic formulations have a specificity of action under the “Law of Similars,” activated water and/or alcohol can potentially provide substantial clinical benefits for a wide range of illnesses. The clinical benefits occur through the enhancement of the body's alternative cellular energy (ACE) pathway. This can be achieved through the consumption or injection of the activated fluid. It can also occur by placing the fluid in close proximity of the body. Included in this latter approach, is the addition of a small quantity (−0.1 mg/ml) of neutral red dye into the activated water or ethanol, with the solution then being illuminated with a UV light (for example a Halco 13 watt condensed UV light bulb) for 30-60 minutes. Activation of the ACE pathway is shown by the occurrence of UV inducible fluorescence within patchy areas the patient's skin and/or within the oral cavity.
[0030] There are increasing clinical data supporting the proposal that enhancing the ACE pathway can help compensate for illnesses characterized by an insufficiency of cellular energy derived from food metabolism. These conditions include inadequate oxygen from chronic obstructive pulmonary disease (COPD); impaired blood supply from cardiovascular and cardiovascular diseases; and increased energy demands due to infections and during wound healing. Of further interest is the indication that the ACE pathway plays a more unique role, beyond that of food calories, in supporting human cognition and mood.
[0031] This new paradigm has placed special importance on increasing the efficiency and availability of ways of enhancing the ACE pathway. It has also stimulated inquiry into the physics of the proposed KELEA force. The working hypothesis is that KELEA is attracted by free (unbound) electrical charges and may be fundamental in preventing the fusion and possible annihilation of opposing electrical charges. It is envisioned that certain dipolar (dielectric) compounds can capture and then release (transmit) KELEA in an oscillating manner, such that nearby electrostatically bonded water molecules will undergo a degree of charge separation. This loosening of intermolecular hydrogen bonding can be sufficient to enable the separated water molecules to function as direct receivers of KELEA. The body water includes both intracellular and extracellular water, with the latter including blood, lymph and cerebrospinal fluid.
BRIEF SUMMARY OF THE INVENTION
[0032] The invention underscores the distinction between the use of various dietary products as sources of calories and/or biochemical nutrients and their discovered function of much smaller amounts being able to activate water and both non-alcoholic and alcoholic beverages. The patent application does so by describing water and beverage activation by a wide range of products, including certain dietary supplements, pharmaceutical compounds and natural foods. Included in the later is cocoa, an ingredient used to make chocolate. Once the water or beverage is activated, the activating product can be substantially removed by progressive dilutions (as in the practice of homeopathy) or completely removed by highly efficient filtration. The requirement for very small amounts (<1 mg/ml) of activating product is emphasized since it is often more efficient than using larger amounts (>10 mg/ml) of product. These findings will likely result in the widespread adoption of using activated water for human and animal consumption, as well as improving the efficiency of agriculture and of certain water based industrial applications. The terms “enerceuticals”; “waterceuticals”; “alternative cellular energy”; “ACE Water” and “KELEA Activated Water” convey the essence of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Not Applicable and none included
DETAILED DESCRIPTION OF THE INVENTION
[0034] To formally establish that water itself is being activated, many of the water activation studies described in the Applicant's earlier patent applications using tap water have been repeated using distilled water (e.g. Arrowhead Distilled Water supplied by Nestlé). The focus of this Application is on the successful use of dietary supplements and certain foods, including cocoa, as practical means of activating water and both non-alcoholic and alcoholic beverages. The level of water activation is primarily assessed by progressively weighing the treated distilled water in capped, but not completely sealed 1 oz glass containers. (A 200 gm electronic digital Sartorius balance reading to 0.1 mg is used in most weighing experiments.) Both the rate and extent of weight loss occurring over several hours and in some experiments over days and even over many months have been made. (As noted previously, while the weight of containers with regular water remains essentially stable [<0.1 mg/ml loss over several hours]; the weight of containers with activated water will exceed >0.5 mg/ml over the same period of time and may typically continue to >1.0 mg/ml within 24 hours.) This approach can be followed by testing for the ability of ˜10% of the activated water to induce significant weight loss in a secondary container with 90% added regular distilled water.
[0035] The other major parameter of water activation is testing for dynamic linear and to-and-fro dissolving patterns of sprinkled neutral red dye particles, which remain on the surface of the water. This dynamic pattern contrasts with the slowly, concentrically spreading dissolving pattern seen when neutral red dye is sprinkled onto inactive water. (An exception to this test is when the surface tension of the activated water is so reduced that the neutral red dye particles become submerged and the dissolving dye tends to be less linear). Another useful criterion of activation is UV light fluorescence of solutions of activated water with dissolved neutral red dye (˜0.1 mg/ml). The fluorescence does not occur with solutions of inactive water and dissolved neutral red dye.
[0036] Absolute ethanol and very high alcohol content beverages, such as Stroh Rum (80% ethanol) or EVERCLEAR grain alcohol (75.5% ethanol) will naturally show a dramatic dissolving pattern of neutral red dye and fluorescence of solutions with neutral red dye. It proceeds to a much greater extent than that of even highly activated water. Yet these activities, as well as measurable weight loss in closed containers, can still be greatly enhanced using various dipolar materials. Moreover, when dissolved humic acid is added, there is a slow formation of bubbles, which rapidly collapse.
[0037] The range of compounds able to activate water and ethanol containing fluids is ever increasing. Moreover, the efficiency of humic acids, zeolites, kaolin and other ceramics in activating either water or beverages can be significantly enhanced by heating to ˜1,000° C. or higher in either a vacuum furnace or an inert gas filled furnace. (The heating is intended to disrupt covalent bonds in favor of unbound electrical charges). A method practiced over the last several months with supporting clinical evidence of efficacy has been the activation of Stroh Rum in a 500 ml bottle using 50 mg of humic acid, which had previously been subjected to an hour of heating at 1,000° C. Eighty (80) ml aliquots of activated rum (80% ethanol) are removed at various times and diluted to 800 ml with distilled water, to achieve an 8% ethanol solution. Eighty (80) ml of this diluted solution is further diluted 10 fold the next day to achieve a 0.8% ethanol solution and on the next day diluted 2 fold to reach an acceptable 0.4% ethanol concentration. This material clearly tests positive in assessments of its kinetic activity, benefits of drinking, testing on plants, etc. Several layers of Glad “Cling Wrap” (Oakland Calif.) are used to help seal the tightly screwed capped containers, when not being used to dispense activated liquid. The containers of activated water are stored separately from water samples designated as control water in various testing procedures. Otherwise, the activated solutions can lead to partial activation of the nearby water.
[0038] The amounts of products required for water activation using heated humic acids can be less than the 0.1 mg/ml used in the above illustration. Moreover, the removed 80 ml aliquots of activated rum can be replaced with fresh rum as it is being used, without an overall loss of activity over time. As with other particulate materials being used for liquid activation, the humic acids can be reused, if recovered from the activated fluid by sedimentation or by filtration (discussed later).
[0039] Various soluble pharmaceutical products have also been shown to have water-activating properties, including small amounts of procaine, Lidocaine, niacin and Dilantin. So too can many tinctures used in the formulation of homeopathics (available from Biorin Corp. Newtown square, Pa.). Of the foods tested, extracts of leaves and/or seeds of moringa oleifera trees are effective as are leaves and stems of the Ashitaba plant. HB-101, a Japanese terpene-rich tree sap extract and d-limonene, which is derived from orange peel, can also readily activate water. Certain fermenting bacteria and yeasts also produce water activating components, but their safety has not been established.
[0040] Of special interest because of its ready acceptance by the public, is the discovery of the quite remarkable water-activating activity of cocoa ( cocao ), as shown by using as little as 0.1 mg/ml of store purchased, packaged material. (Indeed, it is less effective and only active over a short period of time when large quantities (>10 mg/ml) of cocoa are added to distilled water. Cocoa is mainly derived from the fruit seeds of the Theobroma cacao tree, but can also be extracted from kola nuts and from certain tea plant leaves. Its major ingredient is theobromine, a dipolar molecule. The cocoa products tested included 8 oz and 8.8 oz packages of Chirardelli Premium Baking Cocoa and Droste Cocao, respectively. Given the small amount of cocoa required, each single package could potentially directly activate over 2,000 liters of water or beverage. A clue to the potential water activating properties of cocoa and of certain other herbal extracts is reports of their broadly based medicinal benefits. While others have attributed these benefits to the products' biochemical properties, the Applicant has discovered their biophysical capacity for activating liquids.
[0041] Proof that the beneficial activity of various natural products is intrinsic to their ability to activate water and not due to their biochemistry is provided by several lines of evidence: i) comparable activation of water is achievable using external energy delivering devices; ii) the level of activity tends to be inversely related to the amount of added component, with the exception of insoluble pellets; iii) the activity is retained through several 10 fold dilutions, as practiced in homeopathy; iv) activity is retained after all of the added material is removed by filtration. A simple demonstration of the latter is obtained by using the Zero Water device manufactured by Zero Technologies, 4510 Adams Circle, Bensalem Pa. 19020, to ensure removal of the water activating components; v) the levels of water and beverage activation can steadily increase over several months if the activated liquids are maintained in tightly sealed containers and vi) sealed containers of activated liquids can be used to activate nearby fluids, without any need for direct mixing of the two liquids.
[0042] Attributing the beneficial effects of using these compounds to the physics of fluid activation stands in sharp contrast to the generally accepted notions of their biological functions. For example, humic/fulvic acids and zeolites are commonly regarded as sources of bioavailable minerals. Several of the listed products are regarded as powerful anti-oxidants. Niacin is identified as a vitamin, while procaine, Lidocaine and Dilantin are thought to function as inhibitors of neurotransmission. Homeopathic tinctures are viewed to act selectively in treating the same sets of symptoms as are inducible when administered in larger quantities to normal individuals (Law of Similars). More recent concepts relating to many of the compounds include their possible intracellular influences upon gene expression (epigenetic effects). These effects can arguably lead to the increased production of certain beneficial hormones and neurotransmitters, e.g. endorphins in the case of cocoa containing chocolate.
[0043] The basic discovery is that various naturally occurring materials, including cocoa, can be used in small quantities to activate fluids. These products can seemingly act as antennas to capture an environmental energy, tentatively called KELEA. Possibly, via an oscillatory mechanism, some of these compounds can undergo some adjustment so as to release the absorbed energy, which can, thereby, be transferred to nearby fluid molecules. The transmitted energy reduces the intermolecular hydrogen bonding of the fluid molecules, potentially exposing the separated charges to the direct absorption of KELEA. This can lead to further activation of the fluid over time, as has been repeatedly seen. Once this phase of continuing further activation is achieved, the remaining presence of the initial dipolar material is no longer required and can be removed by dilution or by filtration. The recovered materials can be reused. The activated fluids can also be used to activate added fluids, including water. Fluid activation can, therefore, be a highly efficient, inexpensive, process with essentially unlimited potential.
[0044] The body can also produce KELEA absorbing materials, termed ACE pigments. They can be fluorescent, especially in the presence of certain dyes including neutral red dye. They are occasionally magnetic and can show alternating attraction and repulsion attraction when suspended in water. Chemically, they include various aromatic structures and can bind to various minerals. They form within cells, but may also form abiotically, along with the synthesis of lipid membranes and other structures.
[0045] It is also likely that electrical charges within the body can act as KELEA absorbing materials. These can include coordinated electrical activity of skeletal muscles, heart and brain. Furthermore, there may be a complementary, positive feedback relationship between activated water and electrical activity of organs in the absorption and spreading of KELEA. This is suggested by the capacity of laughter to activate water and the ability of activated water to elevate the mood of individuals.
[0046] It is reasonable to suppose that KELEA can also be diverted from its role in activating water. Microwave of homeopathic formulations is stated to diminish its beneficial activity. Compounds could absorb KELEA and either not release it, transfer it into a non-usable energy, e.g. heat. It is certainly possible that stress in some way can act as a drain on KELEA. Conceivably, it could be fast beta brain waves, tachycardia, cortisol, adrenaline, etc.
[0047] The invention now being described, it will be apparent to one of skill in the art that the findings are reflective of a new paradigm. The appended claims represent a rather narrow series of immediate practical applications of the findings. Modifications and extensions of these claims will undoubtedly follow without departing from the spirit and scope of the invention. | The Applicant has identified a biological energy pathway, which is distinct from photosynthesis and from the generation of cellular energy through normal metabolism. It is referred to as the third or the alternative cellular energy (ACE) pathway. This pathway is expressed through an energy acquired kinetic activity of water molecules. The present application extends on the breadth of compounds capable of transferring a natural force called KELEA, (kinetic energy limiting electrostatic attraction) to water and to both non-alcoholic and alcoholic beverages. They include common dietary supplements such as humic acids and common foods, such as cocoa. These products can be repeatedly used for liquid activation at very low quantities and can be removed from the liquid prior to the liquid being used for biological purposes. The studies have widespread practical applications in human and animal health as well as in agriculture. The studies also provide for a better understanding of the practice of homeopathy. | 0 |
BACKGROUND
[0001] The objective of the present invention is a method of producing CdTe solar cells with increased efficiency.
[0002] The distribution of thin-film solar cells may be accelerated further by increasing their electric efficiency in light conversion. Solar cells based on CdTe have proven particularly promising in this respect.
[0003] In the state of the art, the CdTe solar cell has the following structure: on a glass substrate, a transparent conducting oxide layer (TCO) is deposited as front contact. The TCO layer can include a high resistive buffer layer which helps to minimise the shunting effect in solar cell. On this, a layer of cadmium sulfide (CdS) and on top of that, a layer of cadmium telluride (CdTe) are deposited. Finally a metal layer is applied to collect the charge carriers. This process is called superstrate configuration.
[0004] In producing the solar cells the substrate (preferably glass) forms the base on which the subsequent layers are deposited one after another.
[0005] In CdTe solar module preparation normally the thickness of the CdTe layer is maintained in the range of 4 to 5 μm. However, theoretical simulations of the CdTe solar cells show that solar cells with 1 μm CdTe layer could also yield reasonable high efficiency. In principle reducing the CdTe film thickness from 4 to 2 μm could help to reduce CdTe material consumption by 30-40% in module production. The CdTe film thickness reduction would also help to reduce layer deposition time and thereby expedite module production.
[0006] High efficiency solar cells are normally achieved with CdTe deposition at substrate temperatures>500° C. The CdTe layer at this temperature has large grains which could result in formation of pinholes. Therefore, simply reducing the layer thickness has several negative influences over the solar cell efficiency and longtime stability. While reducing the film thickness (<3 μm), pinholes are formed in the CdTe layer leading to shunting of the solar cells. This problem will be more pronounced if there is an etching process involved in solar cell production which will lead to poor performance of the solar cell. Furthermore, the reduction in shunt resistance value leads to a low fill factor and eventually reduced efficiency. Therefore, minimizing the pinhole formation in CdTe layer is necessary in order to obtain high efficiency solar cells.
[0007] In addition to this, increasing the p-doping of the CdTe layer is also important to achieve high efficiency solar cells. Further increase in efficiency of the CdTe solar cells may be achieved by doping the CdTe layer. According to the theoretical predictions, heavy p-doping of CdTe is limited due to the formation of the self-compensation effect. Only a certain level of p-doping can be achieved by using an appropriate doping element and a process providing a doping element to the CdTe layer after depositing the CdTe layer. During the preparation of the CdTe solar cell, the extrinsic p-doping of CdTe layer is normally done after the activation process and involves post annealing treatment to induce diffusion of doping elements. The well-known and easy p-dopant for CdTe layer is Cu.
[0008] The object of the present invention is to obtain a solar cell comprising a doped CdTe layer with a reduced thickness and without pinholes. Furthermore, it is the object of the present invention to simplify the production process of CdTe solar cells.
SUMMARY
[0009] The present invention proposes a method to produce thin film CdTe solar cells having a pin-hole free and uniformly doped CdTe layer with a reduced layer thickness. The method according to the present invention is an efficient way to prevent shunting of the solar cells, to improve reliability and long-term stability of the solar cells and to provide a uniform doping of the CdTe layer. This is achieved by applying a sacrificial doping layer between a first CdTe layer having large grains and a second CdTe layer having small grains, which together form the CdTe layer of the solar cells. Furthermore it provides the possibility to eliminate the CdCl 2 activation treatment step in case the sacrificial doping layer comprises a halogen.
DETAILED DESCRIPTION
[0010] According to the invention, the process of producing a CdTe solar cell comprises a step of forming a first CdTe layer having large grains on a base layer, a step of forming a sacrificial doping layer comprising a doping element on the first CdTe layer and a step of forming a second CdTe layer having small grains on the sacrificial doping layer.
[0011] The preferred material of the sacrificial doping layer is selected out of a group of materials comprising copper, phosphorus, antimony, bismuth, molybdenum or manganese as the doping element. According to one embodiment, the doping element is provided as an elemental layer. In another embodiment, the doping element is provided in a combination of different elements, for instance copper and antimony or antimony and bismuth, or in a composition, wherein the composition is preferably a compound of any of the mentioned doping elements with a halogen, for instance SbCl 3 . The preferred halogen for the composition of the sacrificial doping layer is fluorine (F), most preferred chlorine (CI). The preferably used compounds are chlorides.
[0012] The sacrificial doping layer can be applied using methods according to state of the art. Preferably used are physical or dry chemical processes or wet chemical processes such as, but not limited to:
Sputtering, Electro-deposition, Spraying solution of compound comprising halogen, wherein the compound is dissolved in water or in another known solvent, Spin coating, Dipping the substrate (or the surface of the first CdTe layer) into a solution which contains the doping element or a compound of it, Sponge roller coating, etc.
[0019] Compounds comprising a halogen are preferably applied by wet processing, more preferably by sponge roller coating.
[0020] The thickness of the sacrificial doping layer depends on the dimensions of the CdTe layer resulting from fusion of the first CdTe layer and the second CdTe layer and on the used doping element. Regarding the thickness of the CdTe layer, the thickness of the sacrificial doping layer is chosen such that a predetermined doping level of the CdTe layer is achieved when the sacrificial doping layer is completely dissolved. In case of elemental antimony as the sacrificial doping layer, the thickness of the sacrificial doping layer is preferably approximately one thousandth of the thickness of the CdTe layer. Some examples are given in Table 1, where also the respective approximate thicknesses of the first and the second CdTe layer are given.
[0000]
TABLE 1
1 st CdTe
2 nd CdTe
CdTe layer
Doping layer
layer
layer
total
thickness
thickness
thickness
thickness
in case of Sb
(nm)
(nm)
(nm)
(nm)
4000
1000
5000
5
2400
600
3000
3
1600
400
2000
1-2
500
500
1000
0.5-1
[0021] However, also other doping elements or compositions comprising the doping element may be used. Generally, the thickness of the sacrificial doping layer is preferably in a range of 2 nm to 15 nm. If copper is used as the doping element, the thickness of the sacrificial doping layer should be reduced with respect to that when using other doping elements, since a high degree of copper would lead to degradation of the solar cell over time. Preferably, the thickness of a sacrificial doping layer comprising copper as the doping element should be 30% smaller than the thickness of a sacrificial doping layer comprising another doping element, for instance antimony.
[0022] The sacrificial doping layer is preferably applied on the first CdTe layer at a substrate temperature in the range from room temperature to 350° C. The substrate temperature should not exceed 350° C., since higher substrate temperatures would make it difficult to apply the sacrificial doping layer with the mentioned small thickness due to re-evaporation issues. If compounds comprising a halogen are used for applying the sacrificial doping layer, the substrate temperature is preferably in the range of room temperature to 100° C.
[0023] The first CdTe layer is applied on a base layer as a layer having large grains. The grains of the first CdTe layer have sizes in the order of micrometers, for instance in the range of 2 μm to 5 μm. This is achieved by depositing the first CdTe layer at a substrate temperature in the range of 490° C. to 540° C., wherein the thickness of the first CdTe layer lies between 0.5 μm and 6 μm, more preferably between 1 μm and 1.8 μm. The base layer is a layer stack comprising a transparent substrate, a transparent front contact layer and a CdS layer in case the solar cell is produced in a superstrate configuration. The base layer is a layer stack comprising a substrate and a back contact layer in case the solar cell is produced in a substrate configuration. Further details of these configurations are described later.
[0024] The thickness of the second CdTe layer lies preferably between 1% and 100% of the total thickness of the first CdTe layer depending on the total CdTe layer thickness requirement. More preferably, the thickness of the second CdTe layer lies between 20% and 30% of the total CdTe layer thickness. The total CdTe layer thickness can be in the range of 0.5 μm to 8 μm. Only for very thin total CdTe layers with a layer thickness of 0.5 μm to 1.5 μm, the thickness of the second CdTe layer can be around 40-50% of the total CdTe layer thickness in order to fill the pin-holes and/or grain boundaries of the first CdTe layer. The thickness percentage of the second layer thickness is given only as an example. According to the invention, the method can work with second layer thickness in any of the thickness range.
[0025] The second CdTe layer is applied as a layer having small grains and serves to fill or cover the pin-holes and/or grain boundaries of the first CdTe layer. The grains of the second CdTe layer have sizes in the order of nanometers, for instance in the range of 100 nm to 500 nm. Thus the formation of shunting between the back contact and the front contact of the solar cell as well as the migration of impurities along the grain boundaries within the CdTe layer can be reduced or avoided. The deposition of a small-grain layer is achieved by depositing the second CdTe layer at a substrate temperature in the range from 200° C. to 350° C.
[0026] The first and the second CdTe layer can be deposited by any known method including but not limited to close space(d) sublimation (CSS), chemical bath deposition (CBD), sputtering, electro-deposition or any other physical or chemical methods.
[0027] According to one embodiment of the method for producing a solar cell, the method further comprises a temperature treatment step performed after depositing the second CdTe layer. That is, the temperature treatment step may be performed directly following the step of applying the second CdTe layer or may be performed at a later process step, for instance after applying a cover layer, which might be a sacrificial cover layer.
[0028] The temperature treatment step includes heating the substrate to a temperature in the range of 300° C. to 550° C. Most preferably, the substrate temperature during the temperature treatment process should not exceed 450° C. if the second CdTe layer lies open, i.e. is not covered by another layer, in order to prevent re-evaporation of the CdTe.
[0029] Preferably, a material containing a halogen is provided on the surface of the second CdTe layer during the temperature treatment step. This process step corresponds to the so called activation step known from the state of the art in the production of CdTe solar cells. Usually, CdCl 2 is used as the material containing a halogen for this temperature treatment step, wherein the CdCl 2 is applied onto the CdTe layer by wet chemical method or by vacuum evaporation followed by annealing in air atmosphere at defined temperature (normally in the range of 380° C.-440° C.). The benefits of this activation step include reduction of lattice mismatch between the CdS/CdTe layers and CdTe layer grain boundary passivation. The CdCl 2 activation induced inter-diffusion between the CdS and CdTe layer helps to achieve smooth electronic band transition at the CdS/CdTe junction. However, a disadvantage of this approach is that the CdCl 2 is a potentially hazardous material and therefore difficult to manage in production line.
[0030] If the sacrificial doping layer comprises a halogen, the use of CdCl 2 may be avoided, since the halogen component comprised in the sacrificial doping layer helps in passivating the grain boundaries in the CdTe layer. Therefore, the temperature treatment step of the present invention is preferably performed without providing a halogen containing material on the surface of the second CdTe layer, since the inventive method mimics the CdCl 2 activation process under these conditions.
[0031] The thermal energy available during the temperature treatment step induces decomposition of the sacrificial doping layer into its components and/or diffusion of its components, in particular of the doping element, into and/or through the CdTe layer. Thus, the sacrificial doping layer is broken down, which characterises the doping layer as a sacrificial layer. In the result, the first CdTe layer and the second CdTe layer are now bordering on each other and form the CdTe layer of the solar cell.
[0032] However, the production process of solar cells may comprise different process steps involving higher temperatures, for instance the deposition of CdTe layers. Therefore, dissolving of the sacrificial doping layer and diffusion of its components may also occur, at least partially, during the deposition of the sacrificial doping layer, the deposition of the second CdTe layer and/or other process steps performed after applying the second CdTe layer, for instance a process step for applying a contact layer. Therefore, the above mentioned temperature treatment step may be preserved, if a halogen containing sacrificial doping layer is used and if the process steps following the step of applying the sacrificial doping layer provide a thermal budget sufficient for dissolving the sacrificial doping layer and diffusing the doping element.
[0033] Since the diffusion of doping elements takes place from “inside” the CdTe layer, the CdTe layer is doped more uniform than it is in case of providing a doping layer on top of the deposited complete CdTe layer as it is state of the art. At least, a nearly uniform doping of the CdTe layer is achieved applying a lower thermal budget to the solar cell during the production process as compared to processes according to the state of the art. “Nearly uniform doping” means that no or only a small concentration gradient of the doping element can be measured within the CdTe layer.
[0034] In another embodiment of the invention, depending on the doping layer material selection, the excess doping element, i.e. doping element atoms which cannot be incorporated into the CdTe crystals, can accumulate on the surface of the second CdTe layer. This happens due to the grain boundary assisted preferential impurity diffusion, especially due to the second CdTe layer with smaller grains. The excess doping elements can be washed or rinsed away by using suitable solvents or a following process of nitric-phosphoric acid etching can remove it.
[0035] The inventive method for producing a solar cell may be used for producing solar cells in a superstrate configuration or in a substrate configuration.
[0036] The method for producing a solar cell in superstrate configuration further comprises providing a transparent substrate, preferably of glass, applying a transparent front contact layer or layer stack, for instance of TCO, and applying a CdS layer on the transparent front contact layer or layer stack. After applying the CdS layer, the above described inventive method is performed, wherein the layer stack comprising the transparent substrate, the transparent front contact layer and the CdS layer serves as the base layer for applying the first CdTe layer. That is, the first CdTe layer, the sacrificial doping layer and the second CdTe layer are applied in this order onto the CdS layer. Further, the described temperature treatment process, for instance a CdCl 2 activation process and nitric-phosphoric acid etching process, may be performed, before applying a back contact layer or layer stack.
[0037] The CdTe surface is washed using suitable solution such as water or methanol. The back contact layer may comprise a metal, any other suitable conductive material or a suitable semiconducting layer (such as Sb 3 Te 2 ) according to the state of art.
[0038] In the production process of substrate configuration solar cells, the steps in addition to the steps of applying the first CdTe layer having large grains, applying the sacrificial doping layer and applying the second CdTe layer having small grains are performed basically in a reverse order. The substrate can be a flexible metal foil such as molybdenum which can serve as back contact to collect the photo induced electrical charges or can be any other suitable substrate according to the state of art. Thus, first a substrate is provided on which the back contact layer or layer stack is applied, followed by applying the first CdTe layer, the sacrificial doping layer and the second CdTe layer. That is, the layer stack comprising the substrate and the back contact layer serves as the base layer for applying the first CdTe layer. Subsequently, the CdS layer and the transparent front contact layer, for instance TCO, are applied, wherein a temperature treatment process as described above may be performed after applying the second CdTe layer or even after applying the CdS layer and/or the transparent front contact layer. Optionally, depending on the CdS and TCO deposition methods, the diffusion of the doping element can also happen already during CdS and/or TCO deposition process. In case a CdCl 2 activation process is involved, the doping element can also diffuse during the activation process. In such conditions, an additional post annealing treatment to diffuse the doping element may not be necessary.
[0039] The process steps of applying a (transparent) substrate, applying a front contact layer, applying a CdS layer and applying a back contact layer are performed according to well-known methods from prior art and are therefore not described in detail herein. It should be noted that, in the production process of substrate configuration solar cells, the step of applying a CdS layer should be performed at relatively low substrate temperatures in the range of 200° C. to 350° C. in order to prevent re-evaporation of the CdTe layer. This can be achieved by using a well-known sputtering process for depositing the CdS layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 schematically shows the layer structure of a solar cell according to the state of the art. Said solar cell comprises on the substrate ( 1 ) a layer sequence consisting of front contact ( 21 ), CdS layer ( 3 ), CdTe layer ( 4 ) and back contact ( 22 ).
[0041] FIGS. 2 a to 2 d schematically shows the layer sequences, as they may be observed during the course of the method according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] The method according to the invention is explained in the following in a first exemplary embodiment showing the making of a solar cell in superstrate configuration, without intending to imply a restriction to said embodiment.
[0043] As shown in FIG. 2 a , the front contact ( 21 ) and the CdS layer ( 3 ) have already been applied on the transparent substrate ( 1 ) by means of methods according to the state of the art. As front contact ( 21 ), a 450 nm thick transparent bi-layer [Fluorine doped tin oxide (350 nm) as conducting layer and tin oxide (100 nm) as high resistive buffer] was applied (as TCO). The CdS layer ( 3 ) reaches a thickness of 90 nm and was deposited using CSS technique. On this, the first CdTe layer ( 41 ) according to the invention is deposited with a thickness of 1.6 μm. The deposition process was performed as a CSS process at a substrate temperature of 530° C. resulting in large grains of the deposited layer.
[0044] FIG. 2 b schematically shows the applied sacrificial doping layer ( 5 ) above the first CdTe layer ( 41 ). The sacrificial doping layer ( 5 ) consists of elemental antimony (Sb) and was deposited with a thickness of 2 nm using a sputter process at a substrate temperature of 280° C.
[0045] FIG. 2 c schematically shows the layer stack of the solar cell after depositing the second CdTe layer ( 42 ) on the sacrificial doping layer ( 5 ). The second CdTe layer ( 42 ) was deposited with a thickness of 400 nm using a CSS process at a substrate temperature of 300° C. The second CdTe layer ( 42 ) has small grains which cover the grain boundaries of the first CdTe layer ( 41 ). The sacrificial doping layer ( 5 ) does not cover the grain boundaries of the first CdTe layer ( 41 ) completely caused by the very small layer thickness of the sacrificial doping layer ( 5 ). However, it is uniformly distributed over the first CdTe layer surface. This ensures uniform doping of the resulting CdTe layer. Furthermore, the sacrificial doping layer ( 5 ) starts to break up during the deposition of the second CdTe layer ( 42 ), wherein the antimony moves into the first CdTe layer ( 41 ) as well as in the partly deposited second CdTe layer ( 42 ). However, since the antimony is not diffused into the first CdTe layer ( 41 ) and the second CdTe layer ( 42 ) to a large degree at this process step, the already diffused antimony atoms as well as a reduced thickness of the sacrificial doping layer ( 5 ) are not illustrated in FIG. 2 c.
[0046] Subsequently, the known CdCl 2 activation step is performed at a temperature of 385° C. for 20 min.
[0047] FIG. 2 d schematically shows a solar cell after completing the back contact procedure. A back contact ( 22 ) comprising a metal, in this case molybdenum (Mo), has been created having a layer sequence which corresponds to that known from prior art. As shown, the sacrificial doping layer ( 5 ) is completely broken down and diffused into the CdTe layer ( 40 ) resulting from the fusion of the first CdTe layer ( 41 ) and the second CdTe layer ( 42 ), wherein the resulting CdTe layer ( 40 ) is doped with antimony (indicated by the points within the CdTe layer ( 40 )). The diffusion of the doping element into the first and the second CdTe layers ( 41 , 42 ) as well as the total breakdown of the sacrificial doping layer ( 5 ) may happen at any time during the CdCl 2 activation step and/or during the creation of the back contact ( 22 ) resulting in the shown layer arrangement.
[0048] The CdTe layer ( 40 ) is nearly uniformly doped, which means that no or only a small concentration gradient of the antimony in the CdTe layer ( 40 ) can be seen.
LIST OF REFERENCE NUMERALS
[0000]
1 Substrate (glass)
21 Front contact (transparent, TCO)
22 Back contact (metal)
3 CdS layer
4 CdTe layer (state of the art)
40 CdTe layer
41 First CdTe layer
42 Second CdTe layer
5 Sacrificial doping layer | The present invention proposes a method to produce thin film CdTe solar cells having a pin-hole free and uniformly doped CdTe layer with a reduced layer thickness. The method according to the present invention is an efficient way to prevent shunting of the solar cells, to improve reliability and long-term stability of the solar cells and to provide a uniform doping of the CdTe layer. This is achieved by applying a sacrificial doping layer between a first CdTe layer having large grains and a second CdTe layer having small grains, which together form the CdTe layer of the solar cells. Furthermore it provides the possibility to eliminate the CdCl 2 activation treatment step in case the sacrificial doping layer comprises a halogen. | 8 |
COPYRIGHT NOTICE
[0001]
[0000]
Dan Alan Preston
US Citizen
US Resident
Bainbridge Island,
WA
Joseph David Preston
US Citizen
US Resident
Bainbridge Island,
WA
Marc A. Derenburger
US Citizen
US Resident
Bremerton, WA
Carin L. Douglass
US Citizen
US Resident
Silverdale, WA
Paul M. Peterson
US Citizen
US Resident
Bremerton, WA
Kyle A. Yeats
US Citizen
US Resident
Port Orchard, WA
[0002] Contained herein is material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the United States Patent and Trademark Office patent file or records, but otherwise reserves all rights to the copyright whatsoever. The following notice applies to the software, screenshots and data as described below and in the drawings hereto and All Rights Reserved.
FIELD OF THE INVENTION
[0003] This invention generally relates to the establishment of a plurality of known locations known in the art as “monuments”; from these monuments located at least on, over, or within the tunnel boring machine's (TBM) start point, known in the art as a “launch start”. The present invention provides among other things an integrated navigation system that provides real-time parametric guidance information to the TBM, relative to the tunnel origin, past course and current trajectory, while simultaneously employing a non-contact measuring system in concert with said origin and course information for the final provision of an as-built map of tunnel dimensions and centerline.
BACKGROUND OF THE INVENTION
[0004] Tunnel boring machines (TBM) are used to excavate circular cross section tunnels through a variety of soil and rock strata. As tunnels are bored regardless of geology, it is imperative the TBM and resulting excavating tunnel stay on the design alignment within the mandated tolerances. It may be very costly if 1. The tunnel veers off alignment wandering outside of the client's purchased Right-of-Way (ROW), 2. The TBM encounters unanticipated geological features or utilities in urban settings, or 3. The tunnel alignment and correction curves exceed the tight tolerances required for sustaining the dynamic envelope of train tunnels and highway tunnels. In order to avoid negative impacts on the TBM, the tunnel surroundings, or underground utilities, it is imperative that TBM be precisely locatable and guided when boring through the earth.
[0005] In addition to the need for precise navigation of the TBM, the tunnel itself must be mapped. The need for mapping in tunnels is twofold. Firstly, an as-built map of the tunnel is needed to compare finished tunnel dimensions to plan requirements. Secondly, the as-built map can be maintained after the tunnel is completed and used as a baseline measurement for reference during subsequent surveys to observe changes in tunnel geometry over time.
[0006] The present methods of TBM guidance primarily use lasers and conventional surveying techniques. Lasers and transit theodolites, originating from the tunnel entrance, are relayed through a network of fixed monuments on the tunnel walls and used to identify the position and attitude of the TBM relative to the desired design location. The precision in identifying the exact location (Northing, Easting, Elevation) of this progressive series of monuments and their growing error as the tunnel extends can lead to improper alignment of the tunnel or missing the end target within the stipulated tolerance. This conventional system using sighted theodolites to advance the monuments used by the laser guidance systems is often adversely affected by error inherent to accuracy of the measuring instruments, light refraction, angle of incidence, and reception. From the final measured monument near the TBM, a servo theodolite with distance measuring capability, along with inclinometers on the TBM, are used to identify the axis of the TBM as well as monitor TBM pitch (up and down), yaw, and rotation depending on their installation orientation. The theodolite locates and reports to the underlying guidance computer prisms attached to the TBM with a known orientation and location relative to the reference frame of the TBM. The motorized station can measure their location as the TBM bores the tunnel. The output from the inclinometers and updated target locations is relayed to a central processing unit which outlines the path for the TBM. Monitoring of TBM vertical alignment is derived from the same methods of angle and distance measurement. The series of monuments affixed to the tunnel wall as the TBM advances is measured for elevation using wire line water level instruments to minimize the accumulation of error relative to elevation. Gyroscopes may also be used to monitor the yaw of the TBM, verified by a surveyor.
[0007] The present state of tunnel mapping utilizes a two-step method. Firstly, the mapping positions are precisely located in reference to a known point outside of the tunnel. This is accomplished using a theodolite measurement device. If the tunnel curves, mirrors are used to reflect the beam, and the mirrors' locations are measured by the laser measurement device. Each of these mirrors induces additional error in the final measurement of the mapping positions. With the location and orientation of the mapping stations known, the tunnel walls are then measured at several locations with respect to this position. These measurements are typically done using reflector-less laser measurement system; however, other touch-less measurement systems, such as Electronic Distance Measurements (EDM), may be used to measure the distance to the tunnel walls.
[0008] The process of establishing the mapping locations and obtaining measurement is repeated until the entire tunnel has been measured. The distance measurements are then associated with their respective locations to generate a three dimensional map of the tunnel. This process is costly, time-consuming, and labor-intensive, requiring cessation of any work and traffic in the tunnel until survey completion.
[0009] What is needed is an integrated navigation system that provides real-time parametric guidance information to the TBM, relative to the tunnel origin (hereinafter “the pit”), past course, and current trajectory, while simultaneously employing a non-contact measuring system in concert with said origin and course information for the final provision of an as-built map of tunnel dimensions and centerline. The pit is a known point within the earth-centered-earth fixed global positioning system (GPS), and at least one of GPS retransmission and time modulated wireless triangulation architectures provide availability of positioning signals in the otherwise unavailable underground environment of a newly excavated tunnel. As the TBM proceeds along its excavation heading, a vehicle such as a rubber wheeled vehicle or a locomotive delivers ring assemblies, fabricated on-site in the pit to support the recently excavated portion of the tunnel. The constrained curvilinear path, also known as the design centerline, from pit to TBM is regularly traversed by the locomotive which is, in current systems, employed for transport of ring assemblies and muckout.
DESCRIPTION OF RELATED ART
[0010] In a discussion of prior art, European patent application Ser. No. EP20010304645 filed May 25, 2001, titled SELF-CONTAINED MAPPING AND POSITIONING SYSTEM UTILIZING POINT CLOUD DATA generally describes a self-contained mapping and positioning system for underground mining that is capable of mapping the topography of a region, such as a mine tunnel, and further being able to use the mapped data to determine the position of an object, such as a mining vehicle, within the mine tunnel.
[0011] The method described in European patent application Ser. No. EP20010304645 provides only the position of the object, whereas the present invention incorporates positioning as well as automatic course correction as determined by a pre-established path. Furthermore, the present invention includes permanent monuments to be used in post-boring surveys to evaluate changes in tunnel geometry.
[0012] In a discussion of prior art, U.S. patent application Ser. No. 08/304,858 filed Sep. 13, 1994, titled GUIDANCE SYSTEM AND METHOD FOR KEEPING A TUNNEL BORING MACHINE CONTINUOUSLY ON A PLAN LINE generally describes a guidance system and method for keeping a TBM continuously on a plan line. The guidance system requires no machine operator calculations and provides the boring machine operator with a graphic display of past, present, and projected positions of the boring machine from a horizontal and vertical perspective. The system uses a laser beam transmitter placed to the rear of the TBM along with a front opaque target with a horizontal and vertical cross-hair and a rear transparent target with a horizontal and vertical cross-hair. The front and rear targets are disposed on the front and the rear of the boring machine. Also, an on-board programmable computer is installed on the boring machine for imputing data as to horizontal offset and vertical offset readings from the front and rear targets as the boring machine advances forward. Typically the boring machine moves forward in increments of four feet with offset readings taken by the operator after each increment. The offsets are measured in feet up to two decimal places with the readings based on measured positions being wither right or left of the vertical cross-hair and above or below the horizontal cross-hair of the front and rear targets. Further, the on-board computer is programmed to store and provide a laser alignment check for verifying laser setup information and to graphically display alignment errors during a change in the setup of the laser beam transmitter by a survey crew.
[0013] The device described in U.S. patent application Ser. No. 08/304,858 employs a series of lasers to project the path which are prone to error inherent to light refraction, angle of incidence, and reception. The present invention provides the TBM with data via the locomotive, combined with an on-board INS to provide the TBM with the current orientation, direction, and position to compile the projected path and compare with the desired path.
[0014] In a discussion of prior art, U.S. Pat. No. 3,498,673 filed Feb. 19, 1968, titled MACHINE GUIDANCE SYSTEM AND METHOD generally describes a TBM disposed within a tunnel and provided with a guidance system comprising a laser projection unit fixedly supported by a wall of the tunnel and directing its beam onto a mirror-like reflector mounted on the machine, whereby the reflector provides a reflection of the beam on a target also mounted on the machine. The tunnel boring apparatus is steered to maintain the reflection at a predetermined location on the target.
[0015] The method described in U.S. Pat. No. 3,498,673 aligns external lasers with the desired path and is sent through the TBM which is steered such that the TBM keeps the laser within a designated area. Laser guidance systems are prone to error inherent to light refraction, angle of incidence, and reception. The present invention utilizes a locomotive with an INS to position the TBM continuously; this position is then compared to the desired path as programmed into the TBM to provide the TBM with a path that needs to be followed to match the desired path.
[0016] In a discussion of prior art, European patent application Ser. No. EP20030250157 filed Jan. 10, 2003, titled METHOD AND APPARATUS FOR SURVEYING THE GEOMETRY OF TUNNELS generally describes a method and apparatus for surveying the geometry of tunnels comprising measuring the position of a tunnel surface relative to an absolute three-dimensional coordinate system, using at least one reflector-less distance sensor mounted for orientation in three dimensions and calculating a deviation from a predefined geometry for the surface and displaying said deviation in real time.
[0017] The method and apparatus described in European patent application Ser. No. EP20030250157 is well suited to the mapping of tunnels as well as post-boring surveys for maintenance of the tunnel but is not well suited for as-built mapping during the tunneling process. The present invention utilizes permanent monuments for long-term tunnel mapping, utilizes an INS system that is integrated with the self-contained mapping system, and communicates the combined parametric information to the TBM to provide navigational guidance for the TBM.
[0018] So as to reduce the complexity and length of the Detailed Specification, and to fully establish the state of the art in certain areas of technology, Applicant(s) herein expressly incorporate(s) by reference all of the following materials identified in each numbered paragraph below. The incorporated materials are not necessarily “prior art” and Applicant(s) expressly reserve(s) the right to swear behind any of the incorporated materials.
[0019] U.S. Pat. No. 6,707,424 Integrated Positioning System and Method
[0020] U.S. Pat. No. 8,417,490 System and Method for the Configuration of an Automotive Vehicle with Modeled Sensors
[0021] Inertial Navigation, by Kevin J. Walchko, University of Florida, Gainesville, Fla., and Dr. Paul A. C. Mason, NASA Goddard Space Flight Center, Greenbelt Md. Published 2002.
[0022] Real-Time Tunnel Boring Machine Monitoring: A State of the Art Review, by Michael A. Mooney, Bryan Walter, Christian Frenzel. Colorado School of Mines, Golden Co. Published 2012
[0023] Design and Field Testing of an Autonomous Underground Training System, by Joshua A. Marshall and Timothy D. Barfoot. Published Dec. 13, 2007
[0024] Applicant(s) believe(s) that the material incorporated above is “non-essential” in accordance with 37 CFR 1.57, because it is referred to for purposes of indicating the background of the invention or illustrating the state of the art. However, if the Examiner believes that any of the above-incorporated material constitutes “essential material” within the meaning of 37 CFR 1.57(c)(1)-(3), applicant(s) will amend the specification to expressly recite the essential material that is incorporated by reference as allowed by the applicable rules.
SUMMARY OF THE INVENTION
[0025] Although the best understanding of the present invention will be had from a thorough reading of the specification and claims presented below, this summary is provided in order to acquaint the reader with some of the new and useful features of the present invention. Of course, this summary is not intended to be a complete litany of all of the features of the present invention, nor is it intended in any way to limit the breadth of the claims, which are presented at the end of the detailed description of this application.
[0026] The present invention employs the regular traverse of the locomotive between the pit and the TBM as the method for accumulation of parametric guidance information to the TBM, relative to the tunnel origin, past course, and current trajectory; the means of transmission of said information to the TBM for navigation; and the means by which a non-contact measuring system is deployed in concert with said origin and course information for the final provision of an as-built map of tunnel dimensions and centerline.
[0027] To implement the present invention, an integrated system of devices is installed in the pit, on the locomotive, on the TBM, and on the tunnel ring assemblies. Installed in the pit are GPS receivers and GPS re-transmitters. Installed on the locomotive are GPS receivers for the retransmitted signals within the pit, a fault-tolerant inertial navigation system (FTINS) that obtains course information, a self-contained mapping system, a central processing unit (CPU), and a wireless transmitter for information transfer to and from the TBM. Installed on the TBM are a transceiver to receive transmitted origin and course information, a microprocessor and attitude heading reference system (AHRS) for calculation of heading, and various input/output devices. Included in the present invention are permanent monuments affixed to tunnel ring assemblies which are utilized in concert with the aforementioned self-contained mapping system installed on the locomotive, as well as being available for post-boring surveys of tunnel geometry.
[0028] Aspects and applications of the invention presented here are described below in the drawings and detailed description of the invention. Unless specifically noted, it is intended that the words and phrases in the specification and the claims be given their plain, ordinary, and accustomed meaning to those of ordinary skill in the applicable arts. The inventors are fully aware that they can be their own lexicographers if desired. The inventors expressly elect, as their own lexicographers, to use only the plain and ordinary meaning of terms in the specification and claims unless they clearly state otherwise and then further, expressly set forth the “special” definition of that term and explain how it differs from the plain and ordinary meaning. Absent such clear statements of intent to apply a “special” definition, it is the inventors' intent and desire that the simple, plain and ordinary meaning to the terms be applied to the interpretation of the specification and claims.
[0029] The inventors are also aware of the normal precepts of English grammar. Thus, if a noun, term, or phrase is intended to be further characterized, specified, or narrowed in some way, then such noun, term, or phrase will expressly include additional adjectives, descriptive terms, or other modifiers in accordance with the normal precepts of English grammar. Absent the use of such adjectives, descriptive terms, or modifiers, it is the intent that such nouns, terms, or phrases be given their plain, and ordinary English meaning to those skilled in the applicable arts as set forth above.
[0030] Further, the inventors are fully informed of the standards and application of the special provisions of 35 U.S.C. §112, ¶6. Thus, the use of the words “function,” “means” or “step” in the Detailed Description or Description of the Drawings or claims is not intended to somehow indicate a desire to invoke the special provisions of 35 U.S.C. §112, ¶6, to define the invention. To the contrary, if the provisions of 35 U.S.C. §112, ¶6 are sought to be invoked to define the inventions, the claims will specifically and expressly state the exact phrases “means for” or “step for, and will also recite the word “function” (i.e., will state “means for performing the function of [insert function]”), without also reciting in such phrases any structure, material or act in support of the function. Thus, even when the claims recite a “means for performing the function of . . . ” or “step for performing the function of . . . ”, if the claims also recite any structure, material or acts in support of that means or step, or that perform the recited function, then it is the clear intention of the inventors not to invoke the provisions of 35 U.S.C. §112, ¶6. Moreover, even if the provisions of 35 U.S.C. §112, ¶6 are invoked to define the claimed inventions, it is intended that the inventions not be limited only to the specific structure, material or acts that are described in the preferred embodiments, but in addition, include any and all structures, materials or acts that perform the claimed function as described in alternative embodiments or forms of the invention, or that are well known present or later-developed, equivalent structures, material or acts for performing the claimed function.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] A more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the following illustrative figures. In the figures, like-reference numbers refer to like-elements or acts throughout the figures. The presently preferred embodiments of the invention are illustrated in the accompanying drawings, in which:
[0032] FIG. 1 is a perspective view of the locomotive in the launch pit according to the preferred embodiment of the present invention, depicting the physical method for the accumulation of locomotive initial geo-location data at the launch pit and the retransmission of said data to the locomotive.
[0033] FIG. 2 is a block diagram of the components contained within FIG. 1 .
[0034] FIG. 3 depicts an alternate embodiment using a robotic total survey station mounted in the launch pit and a system of survey reflectors.
[0035] FIG. 4 is a block diagram depicting the components within FIG. 3 which provide for the accumulation and transmission of initial geo-location data.
[0036] FIG. 5 depicts an alternate embodiment using a robotic total survey station mounted on the locomotive and a system of survey reflectors in the launch pit.
[0037] FIG. 6 is a block diagram depicting the components contained within FIG. 5 which provide for the accumulation and transmission of initial geo-location data.
[0038] FIG. 7 depicts an alternate embodiment using a docking station and alignment marks at surveyed locations within the launch pit.
[0039] FIG. 8 is a block diagram depicting the components contained within FIG. 7 which provide for the accumulation and transmission of initial geo-location data.
[0040] FIG. 9 is a block diagram of the components contained within the locomotive.
[0041] FIG. 10 is a block diagram illustrating the components contained within the TBM.
[0042] FIG. 11 depicts the process elements associated with the utilization of geo-location input data.
[0043] FIG. 12 depicts the process elements associated with the utilization of updated geo-location information.
[0044] FIG. 13 is a block diagram illustrating the components contained within the fault tolerant inertial navigation system.
[0045] FIG. 14 depicts the process elements accomplished within the fault tolerant inertial navigation system componentry.
[0046] FIG. 15 is a block diagram illustrating the components utilized for the self-contained mapping system.
[0047] FIG. 16 depicts the process elements accomplished by the self-contained mapping system.
[0048] FIG. 17 is a block diagram of the SACore IMM for Automatic Guidance of a TBM.
DETAILED DESCRIPTION
[0049] In the following description, and for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the various aspects of the invention. It will be understood, however, by those skilled in the relevant arts, that the present invention may be practiced without these specific details. In other instances, known structures and devices are shown or discussed more generally in order to avoid obscuring the invention. In many cases, a description of the operation is sufficient to enable one to implement the various forms of the invention, particularly when the operation is to be implemented in software. It should be noted that there are many different and alternative configurations, devices and technologies to which the disclosed inventions may be applied. The full scope of the inventions is not limited to the examples that are described below.
[0050] In the following examples of the illustrated embodiments, references are made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the scope of the invention.
[0051] FIG. 1 illustrates the preferred embodiment of the physical method for the accumulation of locomotive initial geo-location data within the launch pit 105 and the retransmission of said data to the locomotive 100 . The locomotive 100 starts and ends each travel cycle through the tunnel 110 in the launch pit 105 . Surrounding the launch pit 105 are three or more geo-location and retransmission devices 200 . A locomotive mounted transceiver 115 receives and transmits the position data 225 ( FIG. 2 ).
[0052] FIG. 2 describes the components illustrated in FIG. 1 . The geo-location and retransmission devices 200 each contain at least one global positioning system (GPS) receiver 205 , microprocessor 210 , and transmitter 215 . These devices 200 , well known in the art of position determination and land survey techniques, are designed to receive a GPS signal 220 by which position data 225 is determined and relayed to a locomotive mounted transceiver 115 ( FIG. 1 ).
[0053] These commercially available systems utilize two positioning and navigation systems in a single unit, the first is used within sight of earth-orbiting Global Navigation Satellite System (GNSS) satellites and the second in less than optimal GNSS locations. The locomotive 100 ( FIG. 1 ) in the launch pit 105 ( FIG. 1 ) will generally not be in line-of-sight of the earth-orbiting satellites. The locomotive mounted transceiver 115 ( FIG. 1 ) receives transmissions from a group of at least three ground-based beacons stationed at precise known locations, each of which transmits a distinct signal, including location information. The means of data transmission may include wireless protocols such as 802.11g, Bluetooth, time modulated ultra-wide band (TM-UWB) or other such wireless methods as may arise with developing technologies.
[0054] Another embodiment of the present invention, illustrated in FIG. 3 and described by FIG. 4 , uses a pit mounted robotic total survey station 400 comprising a robotic mount 405 , a controller 410 , and a total station 415 (similar in method and construction to the Trimble Series 6), and a survey station transceiver 420 . The pit mounted robotic total survey station 400 is mounted along the perimeter of the launch pit 105 where it utilizes reflective monuments 310 outside of the launch pit 105 to determine its geo-location. A locomotive mounted reflective monument 305 is used to determine the location of the locomotive 100 relative to the known reflective monuments 310 . The survey station transceiver 420 contained within the pit mounted robotic total survey station 400 transmits position data 225 to the survey station transceiver 420 on the locomotive 100 .
[0055] According to yet another embodiment of the present invention, illustrated in FIG. 5 and described by FIG. 6 , a locomotive mounted robotic total survey station 600 , comprising a robotic mount 405 , a controller 410 , and total station 415 . Within the method described by this embodiment, the locomotive mounted robotic total survey station 600 obtains the position of the locomotive 100 by triangulation with at least three reflective monuments 310 at surveyed locations within the launch pit 105 . As depicted in FIG. 9 , the locomotive mounted transceiver 115 is bypassed with this embodiment and position data 225 is direct fed to self-contained mapping system (SCMS) 900 ( FIG. 9 ) onboard the locomotive 100 .
[0056] A less technical yet viable alternative embodiment of the present invention is illustrated in FIG. 7 and described by FIG. 8 , wherein the locomotive 100 stops at a fixed docking station 700 installed at the terminal point of the track in the pit 105 . Alignment marks 705 may also be utilized in this embodiment either independently or in concert with the fixed docking station 700 to establish position data 225 . The surveyed origin point established by the docking station 700 is a direct input to central processing unit one (CPU 1 ) 1520 ( FIG. 15 ) onboard the SCMS 900 ( FIG. 9 ), offsets to the inertial navigation system (INS) are calculated and the INS is updated to the current position and time of position.
[0057] Referring now to FIG. 9 , there is illustrated an embodiment of the present invention describing the componentry mounted on and within the body of the locomotive 100 for the gathering and storage of information related to the guidance of the TBM 1000 ( FIG. 10 ) and the mapping of the tunnel 110 ( FIGS. 1, 3, 5, 7 ). Within the preferred embodiment of FIG. 1 and the alternate embodiment of FIG. 3 , a locomotive mounted transceiver 115 establishes a link by which position data 225 ( FIGS. 2, 4, 6, and 8 ) is transferred to and received by CPU 1 1520 ( FIG. 15 ). In the case of the alternate embodiments of FIGS. 5 and 7 , initial position data is directly provided to CPU 1 1520 ( FIG. 15 ). In each of the described embodiments, the position data 225 ( FIGS. 2, 4, 6, and 8 ) from the SCMS 900 is utilized to either initialize or recalibrate fault tolerant inertial navigation system one (FTINS 1 ) 1515 ( FIG. 15 ) such that a point of origin, also known as initial position, within the launch pit (Position 1 ) is calculated. Data is transmitted from CPU 1 920 via SCMS transmitter 1505 ( FIG. 15 ) to the host PC 910 and to the TBM 1000 ( FIG. 10 ). The data transmitted to the host PC 910 may be stored on internet based storage.
[0058] Referring now to FIG. 10 , the docking process 1135 ( FIG. 11 ) within an embodiment of the present invention establishes the actual position 1020 relative to the locomotive 100 ( FIGS. 1, 2, 3, and 7 ), which is both necessary and sufficient to characterize the actual underground location of the TBM 1000 . Central processing unit 2 (CPU 2 ) 1010 receives updated position information (Position 2 ) 1015 from CPU 1 1520 ( FIG. 15 ) through TBM transceiver 1005 . The TBM 1000 obtains the presumed position (Position 3 ) 1025 from FTINS 2 1030 based on movement of the TBM 1000 (element 1200 ). CPU 2 1010 calculates the difference between the updated position information (Position 2 ) 1015 and the presumed position (Position 3 ) 1025 (element 1205 ), and the difference is applied as a correction to the Position 3 1025 data in FTINS 2 1030 (element 1210 ).
[0059] FIG. 11 depicts the process elements associated with the utilization of position input data provided by the componentry depicted in FIG. 1 , the interaction of componentry depicted in FIG. 9 as the locomotive 100 transits the curvilinear tunnel path 1125 , and the transmission of accumulated data to the TBM 1000 componentry of FIG. 10 . Initial Position 0 is established at the geo-location and retransmission devices 200 (element 1100 ). The time modulated signal with Position 0 data is then transmitted to CPU 1 1520 ( FIG. 15 ) onboard the locomotive 100 (element 1105 ). CPU 1 1520 ( FIG. 15 ) calculates initial position of the locomotive 100 (Position 1 1400 ) (element 1110 ). The Position 1 1400 data is then provided to FTINS 1 1515 ( FIG. 15 ) (element 1115 ). FTINS 1 1515 ( FIG. 15 ) is then updated to Position 1 1400 (element 1120 ).
[0060] Two processes occur as the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) transits a curvilinear path 1120 through the tunnel 110 ( FIGS. 1, 3, 5, and 7 ) from the launch pit 105 ( FIGS. 1, 3, 5, and 7 ) to the TBM 1000 ( FIG. 10 ). The first process is the establishment of guidance information for the TBM 1000 ( FIG. 10 ) by the delivery of a position update to the FTINS 2 1030 ( FIG. 10 ). The second process is the active mapping of the tunnel 110 ( FIGS. 1, 3, 5, and 7 ) as-built, accomplished by the measurement of distance to the tunnel walls 1130 by a SCMS 900 ( FIGS. 9 and 15 ). These processes may be accomplished simultaneously during the transit from launch pit 105 ( FIGS. 1, 3, 5, and 7 ) to docking with the TBM at Position 2 1135 or separately so as to focus on delivery of position data to the TBM 1000 ( FIG. 10 ) on the incoming trip and to focus on tunnel mapping on the outgoing trip.
[0061] Within these two processes, whether simultaneous or separate, information from FTINS 1 1515 ( FIG. 15 ) and the SCMS 900 ( FIGS. 9 and 14 ) is provided to CPU 1 1520 ( FIG. 15 ), which compiles the aforementioned data with the initial position data 1120 . Upon docking 1135 with the TBM 1000 ( FIG. 10 ), the FTINS microprocessor 1320 ( FIG. 13 ) calculates the actual position and provides this data to the onboard CPU 1 1520 ( FIG. 15 ) (element 1140 ). The docking process 1135 establishes actual position relative to the locomotive 100 ( FIGS. 1, 3, 5 , and 7 ) and the TBM 1000 ( FIG. 10 ). All information relative to travel and tunnel measurement from the SCMS 900 ( FIG. 9 ) is retained onboard the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) until its return to the launch pit 105 ( FIGS. 1, 3, 5, and 7 ), where data collected in terms of TBM 1000 ( FIG. 10 ) position and tunnel measurements are uploaded to the host PC 910 ( FIG. 9 ) and may be backed up to internet-based data storage.
[0062] Referring now to FIG. 12 , the TBM 1000 ( FIG. 10 ) obtains the presumed position (Position 3 ) 1025 ( FIG. 10 ) from FTINS 2 1030 ( FIG. 10 ) based on movement of the TBM 1000 ( FIG. 10 ) (element 1200 ). CPU 2 1010 ( FIG. 10 ) calculates the difference between the updated position information (Position 2 ) 1015 ( FIG. 10 ) and the presumed position (Position 3 ) 1025 ( FIG. 10 ) (element 1205 ), and the difference is applied as a correction to the Position 3 1025 ( FIG. 10 ) data in FTINS 2 1030 ( FIG. 10 ) (element 1210 ). There is programmed within CPU 2 1010 ( FIG. 10 ) a known offset distance 1215 from FTINS 2 1030 ( FIG. 10 ) to the steering control point of the TBM 1000 ( FIG. 10 ), and CPU 2 1010 ( FIG. 10 ) applies the aforementioned known offset to the Position 3 1025 ( FIG. 10 ) data (element 1220 ) contained within FTINS 2 1030 ( FIG. 10 ). The designed tunnel route 1225 programmed within the read-only memory of CPU 2 1010 ( FIG. 10 ), and the as-designed tunnel route 1225 is now compared to the current position 1230 . CPU 2 1010 ( FIG. 10 ) on the TBM 1000 ( FIG. 10 ) now establishes a new immediate heading 1235 for the TBM 1000 ( FIG. 10 ) to follow. This new heading is applied to a steering correction 1240 to the TBM 1000 ( FIG. 10 ) for either a manual or automatic pilot to follow.
[0063] FIG. 13 depicts the components in the fault tolerant inertial navigation system (FTINS) 1300 . Both the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) and the TBM 1000 ( FIG. 10 ) are equipped with two inertial measurement units (IMUs) 1305 which include one or more angular rate sensors (gyroscopes) 1310 and one or more accelerometers 1315 which provide information to the FTINS microprocessor 1320 . The output of the FTINS microprocessor 1320 describes the physical location of the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) relative to the known initial position data 225 ( FIGS. 2, 4, 6, and 8 ), and the physical location of the TBM 1000 ( FIG. 10 ) relative to its last position update.
[0064] FIG. 14 depicts the process elements accomplished within the FTINS 1300 ( FIG. 13 ) componentry. The gyroscopes provide (ω x , ω y , ω z ) 1405 and the accelerometers provide ({umlaut over (x)}, ÿ, {umlaut over (z)}) 1410 data. The FTINS microprocessor 1320 ( FIG. 13 ) calculates change in position by integrating the acceleration data 1415 . The FTINS microprocessor 1320 ( FIG. 13 ) then receives the initialized position (Position 1 ) 1400 and compares it to the change in position 1420 . The FTINS microprocessor 1320 ( FIG. 13 ) finally calculates the current position 1425 .
[0065] Referring now to FIG. 15 , there is illustrated an embodiment of the present invention describing the self-contained mapping system (SCMS) 900 mounted within the locomotive 100 ( FIGS. 1, 3, 5, and 7 ). The SCMS 900 uses a vibration isolation device 1510 and reflective monuments 310 installed on, or cast into, the tunnel walls to map the tunnels. The vibration isolation device 1510 comprises: FTINS 1 1515 ; a contact-free 3D scanner 1525 , such as a Light Detection and Ranging or Laser Imaging Detection and Ranging (LiDAR); CPU 1 1520 ; a data storage unit 1530 , such as a hard disk drive or a flash memory device; and a wired or wireless transmitter 1505 . The SCMS 900 is capable of generating a 3D map of the tunnel 110 ( FIGS. 1, 3, 5, and 7 ) during and after the tunnel boring process, generating an accurate measurement of the tunnel centerline, and, through the use of the reflective monuments 310 ( FIGS. 3, 4, 5, and 6 ), the SCMS 900 may be used to observe the movement of fixed points on the tunnel wall during and after the tunnel boring process to determine change in tunnel geometry over time.
[0066] FIG. 16 depicts the process elements accomplished by the SCMS 900 ( FIGS. 9 and 15 ). The SCMS 900 ( FIGS. 9 and 15 ) applies a position offset to the FTINS 1 1515 ( FIG. 15 ) measurements in order to match the FTINS 1 1515 ( FIG. 15 ) reference frame with that of the 3D scanner 935 ( FIGS. 9 and 15 ). The SCMS 900 ( FIGS. 9 and 15 ) then measure the distance to the tunnel wall relative to the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) and geometric tunnel center 1600 . The FTINS 1 1515 ( FIG. 15 ) estimates the absolute position of the locomotive 100 ( FIGS. 1, 3, 5, and 7 ) (element 1605 ). Timestamps 1610 , 1615 are applied to the two measurements and the data is stored. A position offset to the FTINS 1 1515 ( FIG. 15 ) is applied to the laser reference frame 1625 . The data resulting from 1610 and 1625 is then correlated 1620 and used to: generate the geometric centerline of the tunnel 1630 , extract reflective monument measurements 1635 , and generate a 3D mesh of the tunnel wall 1640 . The position of the reflective monuments 310 ( FIGS. 3, 4, 5, and 6 ) can be extracted 1635 by isolating measurements from the 3D scanner 1525 ( FIG. 15 ) which indicate a higher reflectivity, and individual reflective monuments can be identified by their specific reflectivity. Upon completing the trip through the tunnel, the SCMS 900 ( FIGS. 9 and 15 ) uploads the measurements from the FTINS 1 1515 ( FIG. 15 ) and 3D scanner 1525 ( FIG. 15 ) to an external computer via wired or wireless link 1645 for analysis of the as-built tunnel geometry.
Multi-Sensor Data Fusion:
[0067] Those skilled in the art of state estimation, robotics, and advanced defense avionics understand academically that sensor-fusion is the art of combining sensory data or data derived from disparate sources such that the resulting information is in some sense “better” than would be possible when these sources were used individually. This process is predicated on the covariance (or the measure of how much two variables vary together) of non-independent sources. The term “better” in the case above can mean more accurate, more complete, more dependable, or refer to the result of an emerging view or state estimation.
[0068] The data sources for a fusion process are not specified to originate from identical sources or sensors which may or may not be spatially and temporally aligned. Further one can distinguish direct fusion, indirect fusion, and fusion of the outputs of the former two. Direct fusion is the fusion of sensor data from a set of heterogeneous or homogeneous sensors, soft sensors, and history values of sensor data, while indirect fusion uses information sources like a prior knowledge about the environment and human input. Sensor fusion is also known as “multi-sensor data fusion” and is a subset of information fusion through an implementation of the probability theory.
[0069] Probability theory is the mathematical study of phenomena characterized by randomness or uncertainty. More precisely, probability is used for modeling situations when the result of a measurement, realized under the same circumstances, produces different results. Mathematicians and actuaries think of probabilities as numbers in the closed interval from 0 to 1 assigned to “events” whose occurrence or failure to occur is random. Two crucial concepts in the theory of probability are those of a random variable and of the probability distribution of a random variable.
[0070] Implementing the features described above with affordable instruments requires reliable real-time estimates of system state. Unfortunately, the complete state is not always observable. State Estimation takes all the data obtained and uses it to determine the underlying behavior of the system at any point in time. It includes fault detection, isolation and continuous system state estimation.
[0071] There are two parts to state estimation: modeling and algorithms. The overall approach is to use a model to predict the behavior of the system in a particular state, and then compare that behavior with the actual measurements from the instruments to determine which state or states is the most likely to produce the observed system behavior.
[0072] This is not well understood or currently implemented in the construction industry; the approach understood and practiced is logical decisions in linear and deterministic systems. If use cases require higher confidences in measurements, instrument specifications are tightened resulting in the undesired effect of cost and schedule increases. The environment we live and operate in is neither linear nor deterministic; use cases are infinite; and the perverse variability of the systems and potential errors cannot be modeled. The variability of the problem identified above includes aspects other than just spatial (i.e. precise location of the tunnel boring machine); temporal relationships are part of the fundamental intellectual structure (together with space and number) within which events must be sequenced, quantify the duration of events, quantify the intervals between them, and compare the kinematics of objects.
[0073] In any of the embodiments listed above; the use of Fusion Engine (FE) and Kalman filters in the guidance system of the TBM, will greatly improve position accuracy and reduce instrument costs. The FE continuously receives measurements from multiple sources and generates a state estimate and covariance (confidence) of the current position of the TBM; all updated position data measurements received are used to ensure the measurement data is within the FE estimates.
[0074] In order to continuously and accurately estimate the position of the TBM the Kalman filters in the preferred embodiment are implemented as an asynchronous n-scalable Interacting Multiple Model (IMM) estimation Filter. The IMM comprises multiple models of drift from position in order to accurately match the maneuvering and drift expectations.
[0075] Since the drift or progression of the gyros in either FTINS is not known ahead of time, an accurate model cannot be designed, so errors in the position estimation will occur. Adding process noise to model the TBM maneuvers or using a maneuver detector to adapt the filter has been used in the art, but detection delays and large estimation errors during maneuvers are still a problem. It is generally accepted that the Interacting Multiple Model (IMM) estimator provides superior tracking performance compared to a single Kalman Filter.
[0076] The IMM is based on using several models in parallel to estimate the maneuvering TBM's states. Each Kalman Filter, uses a different model for each maneuver, one models a constant state of the TBM, another models a position change in the longitudinal axis while another models a position change in the lateral axis and vertical axis. Switching between these models during each sample period is determined probabilistically. Unlike maneuver detection systems where only one filter model is used at a time, the IMM uses all filters. The overall state estimate output is a weighted combination of the estimates from the individual filters. The weighting is based on the likelihood that a filter model is the correct maneuvering TBM model.
[0077] The IMM estimator is a state estimation algorithm that uses Markovian switching coefficients. A system with these coefficients is described by r models, M 1 , M 2 , . . . , M r , and given probabilities of switching between these models. M j (k) denotes that model j (M j ) is in effect during the sampling period ending at time t k , [t k-1 , t k ]. The dynamics and measurement for a linear system are given by
[0000] x ( k )=Φ j ( k,k− 1) x ( k− 1)+ G j ( k,k− 1) w j ( k− 1), (1)
[0000] and
[0000] z ( k )= H j ( k ) x ( k )+ v j ( k ), (2)
[0078] where x(k) is the system state at time t k , z(k) is the measurement vector at time t k , Φ j (k,k−1) is the state-transition matrix from time t k-1 to time t k for M j (k), G j (k,k−1) is the noise input matrix, and H j (k) is the observation matrix for M j (k). The process noise vector w j (k−1) and the measurement noise vector v j (k) are mutually uncorrelated zero-mean white Gaussian processes with covariance matrices Q j (k−1) and R j (k) respectively.
[0079] The initial conditions for the system state under each model j are Gaussian random variables with mean x j (0) and covariance P j (0). These prior statistics are assumed known, as also is μ j (0)=Pr{M j (0)}, which is the initial probability of model j at t 0 .
[0080] The model switching is governed by a finite-state Markov chain according to the probability π ij =Pr{M j (k)|M i (k−1)} of switching from M i (k−1) to M j (k). The model switching probabilities, π ij , are assumed known and an example is
[0000]
π
ij
=
[
.95
.05
.05
.95
]
.
(
3
)
[0081] A block diagram of the IMM estimator with only two models, for simplicity, is shown in FIG. 17 .
[0082] The inputs to the IMM estimator are {circumflex over (x)} 1 (k−1|k−1), {circumflex over (x)} 2 (k−1|k−1), P 1 (k−1|k−1), P 2 (k−1|k−1), and μ i|j (k−1|k−1), all from the sampling period ending at t k-1 . Where {circumflex over (x)} 1 (k−1|k−1) is the state estimate from filter 1 at time t k-1 using measurements from time t k-1 and P 1 (k−1|k−1) is the corresponding state covariance matrix. Each of the filters use a different mixture of {circumflex over (x)} 1 (k−1|k−1) and {circumflex over (x)} 2 (k−1|k−1) for their input, For r models, this mixing allows the model-conditioned estimates in the current cycle to be computed using r filters rather than r 2 filters, which greatly decreases the computational burden. The inputs to the filters, {circumflex over (x)} 01 (k−1|k−1), {circumflex over (x)} 02 (k−1|k−1), and the corresponding covariance matrices are computed in the Interaction (Mixing) block.
[0083] For the filter matched to M j (k), the inputs are
[0000]
x
^
0
j
(
k
-
1
k
-
1
)
=
∑
i
=
1
r
μ
i
|
j
(
k
-
1
k
-
1
)
x
^
i
(
k
-
1
k
-
1
)
(
4
)
P
0
j
(
k
-
1
k
-
1
)
=
∑
i
=
1
r
μ
i
j
(
k
-
1
k
-
1
)
{
P
i
(
k
-
1
k
-
1
)
+
[
x
^
i
(
k
-
1
k
-
1
)
-
x
^
0
j
(
k
-
1
k
-
1
)
]
⋆
[
x
^
i
(
k
-
1
k
-
1
)
-
x
^
0
j
(
k
-
1
k
-
1
)
]
T
}
,
(
5
)
[0000] where the conditional model probability is
[0000]
μ
i
j
(
k
-
1
k
-
1
)
=
Pr
{
M
i
(
k
-
1
)
M
j
(
k
)
,
Z
1
k
-
1
}
=
1
μ
j
(
k
k
-
1
)
π
ij
μ
i
(
k
-
1
k
-
1
)
,
(
6
)
[0000] and the predicted model probability is
[0000]
μ
j
(
k
k
-
1
)
=
Pr
{
M
j
(
k
)
Z
1
k
-
1
}
=
∑
i
=
1
r
π
ij
μ
i
(
k
-
1
k
-
1
)
.
(
7
)
[0084] Using the measurements, z(k), for the filter matched to M j (k), the updates are computed using the familiar Kalman Filter equations
[0000] {circumflex over (x)} j ( k|k− 1)=Φ j ( k,k− 1) {circumflex over (x)} 01 ( k|k− 1), (8)
[0000] P j ( k|k− 1)=Φ( k,k− 1) P 0j ( k|k− 1)[Φ j ( k,k− 1)] T +G j ( k,k− 1) Q j ( k− 1)[ G j ( k,k− 1)] T (9)
[0000] v j ( k )= z ( k )− H ( k ) {circumflex over (x)} j ( k|k− 1), (10)
[0000] S j ( k )= H j ( k ) P j ( k|k− 1)[ H j ( k )] T +R j ( k ), (11)
[0000] K j ( k )= P j ( k|k− 1)[ H j ( k )] T [S j ( k )] −1 , (12)
[0000] {circumflex over (x)} j ( k|k )= {circumflex over (x)} j ( k|k− 1)+ K j ( k ) v j ( k ), (13)
[0000] P j ( k|k )=[ I−K j ( k ) H j ( k )] P j ( k|k− 1), (14)
[0000] where {circumflex over (x)} j (k|k−1) is the predicted state estimate under M j (k), P j (k|k−1) is the corresponding prediction covariance, v j (k) is the residual, S j (k) is the residual covariance matrix, K j (k) is the Kalman gain matrix, {circumflex over (x)} j (k|k) is the updated state estimate under M j (k), and P j (k|k) is the updated covariance matrix.
[0085] The likelihood of the filter matched to M j (k) is defined by Λ j (k)=f[z(k)|M j (k), Z 1 k-1 ], where f[|] denotes a conditional density. Using the assumption of Gaussian statistics, the filter residual and the residual covariance, the likelihood is
[0000]
Λ
j
(
k
)
=
1
det
[
2
π
S
j
(
k
)
]
exp
{
-
1
2
[
v
j
(
k
)
]
T
[
S
j
(
k
)
]
-
1
v
j
(
k
)
}
.
(
15
)
[0000] The probability for M j (k) is
[0000]
μ
j
(
k
k
)
=
Pr
{
M
j
(
k
)
Z
1
k
}
=
1
c
μ
j
(
k
k
-
1
)
Λ
j
(
k
)
,
(
16
)
[0000] where the normalization factor c is
[0000]
c
=
∑
j
=
1
r
μ
i
(
k
k
-
1
)
Λ
i
(
k
)
.
(
17
)
[0086] These computations are performed in the Model Probability Update block. Finally the combined state estimate {circumflex over (x)}(k|k) and the corresponding state error covariance for the IMM are given by
[0000]
x
^
(
k
k
)
=
∑
j
=
1
r
μ
j
(
k
k
)
x
^
j
(
k
k
)
,
(
18
)
P
(
k
k
)
=
∑
j
=
1
r
μ
j
(
k
k
)
{
P
j
(
k
k
)
+
[
x
^
j
(
k
k
)
-
x
^
(
k
k
)
]
[
x
^
j
(
k
k
)
-
x
^
(
k
k
)
]
T
}
.
(
19
)
[0087] The final state estimate, {circumflex over (x)}(k|k), is the best estimate of the TBM state and P(k|k) is the error covariance matrix for this optimal state estimate.
[0088] For the sake of convenience, the operations are described as various interconnected functional blocks or distinct software modules. This is not necessary, however, and there may be cases where these functional blocks or modules are equivalently aggregated into a single logic device, program or operation with unclear boundaries. In any event, the functional blocks and software modules or described features can be implemented by themselves, or in combination with other operations in either hardware or software.
[0089] Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention may be modified in arrangement and detail without departing from such principles. Claim is made to all modifications and variation coming within the spirit and scope of the following claims. | A system and methods are disclosed for providing the location of a tunnel boring machine (TBM) by establishing of a plurality of known locations or “monuments”; from these monuments located at least on, over or within the TBM's start point, known in the art as a “pit”. The present invention provides among other things an integrated navigation system that provides real-time parametric guidance information to the TBM, relative to the tunnel origin, past course and current trajectory, while simultaneously employing a non-contact measuring system in concert with said origin and course information for the final provision of an as-built map of tunnel dimensions and centerline. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of the miniature football game toy disclosed in the Chilean Pat. No. 26.924 and the Argentinian Pat. No. 190750. In the improved toy of this invention, the "players" are selectively activated at will by the operators participating in the game. The "players" are activated through the touching of a respective key or button located on a control panel. The operators do not waste any physical effort moving the players and are thus able to concentrate their mental ability and ingenuity on producing a fast and lively game whose object is to score points by sending the ball into the opponent's goal area.
Nowadays, a football game toy is well-known wherein two or more operators can play a miniature football game, the simulated game field being a table or board whereon a number of rotatory and transversally slidable rods are mounted perpendicular to the major axis of the "field". Each of these rods is provided with a predetermined number of wooden, metal or plastic figures representing the "players" in the game, these figures being fixed to the respective rod.
Each operator actuates the respective "players" by rotating and/or sliding the cooperating rod, the rotation and/or transverse movement of the "players" sending the ball in the general direction of the opposed or remote goal area in order to score one point.
As the players are fixed to the rotatory rods, the figures forming "play lines" (forward, center and defense), the movement of the rods produces the movement of the complete "line", thus reducing the originality and liveliness of the game. There also exist "football game" toys wherein the "players" are not manually actuated by the operators but the activation of the "players" is produced through the energization of some type of electromagnetic device, said device producing the movement of the "players" to strike the ball.
The above mentioned "football games" do not permit a real competition between two operators but are almost random games due to the fact that the operators have no means of influencing the actuation of the "players" because the activation of the electromagnetic device associated to each "player" is determined by the opening or closing of a set of electronic contacts caused by random positioning of the metal ball on a recess located at the foot of the "player".
In a similar known "football games", the ball is guided from one "player" to another by a suitable channel or guiding slot, and the operators have no means of influencing the movement of the ball.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a novel and improved miniature football game wherein the operation of the "players" is simplified thus saving physical effort on the part of the operators and only requiring the touching of any one of a number of "keys" or switches suitably arranged on control boards or panels located around the edge or border of the table or "field". The control boards are preferably located behind the "goal area" and near the corners of the table.
The keys are so arranged that they can be easily touched and pressed with the finger-tips or with the back of the palms.
When pressing one or more control keys, the respective operator is able to move one or more "players", even if they are not in contact with the ball, since the "players" are suitably arranged on the "field" surface and can be moved alternately forward or backward along a predetermined path which is defined by slots formed in the "field" surface. The "player" activated by the operator can hit the ball sending said ball to another "player" of the same team; the "player" can send the ball directly into the opposing "goal area", or can even intercept the ball which has been played by an opposing "player". Thus the result of the "game" depends only on the mental ingenuity of the two opposing operators.
The surface of the "field" is a lightgauge metal sheet, or a reinforced plastic plate comprising a number of suitably arranged undulations defining guides, slots, or channels to allow the ball to move in the general direction of the "player" opposite to the one hitting the ball. Around the outer edge of the "field" a "fence" (made of plastic material) of a suitable height is provided to prevent the ball from falling out of the "field" in the event of an "off-side".
A novel arrangement is provided for the activation of the "players" comprising an electromagnetic coil with a movable magnetic core linked to a lever arm actuating a sliding arm whereon a respective "player" is mounted, these elements constituting an "actuator".
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described with reference to the accompanying drawings where:
FIG. 1 illustrates a perspective view of a first embodiment of the "actuator" used to activate the "player".
FIG. 1A illustrates the electrical connection of the magnetic coil used in the embodiment of FIG. 1.
FIG. 2 is a part bottom view of the "actuator" of FIG. 1.
FIG. 3 illustrates a perspective view of a second embodiment of the actuator.
FIG. 3A illustrates the electrical connection of the magnetic coil used in the embodiment of FIG. 3.
FIG. 4 is a plan view of the "field", illustrating the arrangement of the "guide slots" on the field surface.
FIG. 5 illustrates a vertical section taken along line A--A of FIG. 4.
FIG. 6 illustrates a vertical section taken along line B--B of FIG. 4.
FIG. 7 illustrates the location of the control panels for activating the "players" of one team.
FIG. 8 illustrates a preferred arrangement of the control keys on the control panels.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a first embodiment of electromagnetical actuator used for activation of the "players" in the football game of the invention. The actuator comprises a frame 1 made of metal sheet or similar material having a hollow core magnetic coil 2 horizontally mounted on the bottom part thereof and inserted into a metal housing 3. This magnetic coil 2 is provided with a metal core 4 slidable mounted in the hollow core of the coil and having a recess 5 formed in the outer end thereof.
The metal housing 3 is mounted in a bracket 6 affixed to the bottom part of said frame 1.
In the lower front portion of bracket 6 the are located two coaxial small diameter holes 7, 8, wherein is inserted a shaft 9.
A long lever arm 10 is suitably fixed to the shaft 9, passing through the recess 5 of the core 4 between the bottom end of said recess and pin 11 located transversely to the core 4 at the open end of the recess 5.
A biassing spring 13 affixed by rivet or a bolt 14 to the under part of the bracket 6 (FIG. 2) is engaged in a half-ring 12 fixed to the transverse pin 11, thus normally holding the core 4 in a position remote from the coil 2. The biassing force of the spring 13 is not strong enough to prevent the core 4 from being moved into the hollow core coil 3 when said coil is energized, but only to return said core 4 to its outward position when coil 2 is de-energized, thus maintaining the lever-arm 10 in its right hand position, as shown in FIG. 1.
In the upper part of frame 1 there is provided a guide rail 15 fixed to said frame 1, a vertical pin 16 being slidably mounted on said rail 15 by means of a sliding support 17 having an eyelet 18 wherein the outer end of the lever arm 10 is engaged. In the left portion of the guide rail 15 there exists a spring 19 to provide a cushioning means for the support 17 and cooperating pin 16 in its movement to the left of the frame 1.
The magnetic coil 2 comprises a high current coil 2a and a low current coil 2b connected in series, the high current coil being shunted by the spring switch 21 when the actuator is de-energized.
When the key switch 161 is pressed, the high current coil 2a is energized and the movable core 4 moves into the hollow coil, moving the pivoting arm lever 10 towards the left-hand side of the actuator (FIG. 1) thus sliding the support plate 17 and attached pin 16 towards the cushioning spring 19.
Suitably located, through a window 20, is a normally closed switch 21, shunting the magnetic coil 2a. When the lever arm 10 reaches its leftward position and the support plate 17 abuts the spring 19, said lever arm 10 pushes the contact 22 opening the electrical shunt coil 2 thus allowing both coils 2a and 2b to remain energized while the switch 161 is kept depressed, without overheating of the coils.
When the coil 2 is de-energized, the biassing spring 13 forces the core 4 out of the hollow coil, thus moving the lever arm 10 to its original position, together with the sliding plate 17 and pin 16. As soon as the coil is de-energized and the spring 13 outwardly moves the core 4, the spring contact 22 closes, thus allowing the high current coil 2a to be again energized by the operator's pressing of the respective control key located on the control panel.
FIG. 3 illustrates a double actuator, similar to the one already described, preferably used to activate the "goal-keeper" of the football game of the invention.
The double-actuator comprises two opposed magnetic hollow coils 302, coaxially arranged, (only one of which is shown for simplicity of the drawing), having a common magnetic core (304). Both coils are similar to the coil used in the embodiment already described, and to prevent any possibility of damage if both keys 162 are pressed simultaneously, said key switches are electrically interlocked allowing only one of the coils to be energized.
Said core (304) presents an elongated recess or slot (305) centrally located, and provided with two transverse pins 311 suitably separated one from the other.
A lever arm 310, affixed to a shaft 309 pivoting in the small diameter holes 307, 308 projects through the opening between the pins 311.
The outer end of lever arm 310 engages the eyelet 318 of sliding support 317 wherein the vertical pin 316 is affixed.
Said support 317 is slidably mounted on the guide rail 315 having springs 319 at both ends thereon for cushioning the movement of the sliding support 317.
Two guide rails 325 are located at a suitable height of frame 301, the lever arm 310 passing through between said rails 325.
Sliding stops 324 are pressed by springs 323 against the lever arm 310, said sliding stops 324 abutting the fixed stop 325, thus maintaining the lever arm 310 in a center location when both coils 302 are de-energized.
When one of the coils 302 is energized, the core 304 moves into the coil forcing the lever arm 310 to move in the same direction as the energized coil. The lever arm 310 presses against the sliding stop 324 and respective springs 323 until the level arm 310 opens the spring contact 322 of the switch 320 (not shown) thus deenergizing the coil 302, the springs 323 and cooperating sliding stop 324 forcing the lever arm 310 to its original center position, the fixed stop 326 preventing over-travel of the lever arm 310 from the center position until any of the coils 302 is again energized by the operator.
FIG. 4 illustrates a top plan view of the "field" for the "football game" of this invention, made of light sheet metal or reinforced plastic material. The surface of the "field" is divided into a number of "player's areas" 101, 102 . . . 119, 120.
Suitably located in each of these areas is formed an elongated narrow slot 101s, 102s, . . . 119s, 120s defining the direction of the alternative movement of the player mounted and affixed to the vertical pin 5 of the respective electromagnetic actuator located beneath the surace of the "field", (FIGS. 5 and 6).
Each "player's area" is defined by undulations, the slopes thereon being in the general direction of the respective slot existing in the "player's area" to direct the ball to the vertical pin 5 projecting through the slot.
FIGS. 5 and 6 illustrate a section taken along lines A--A and B--B of the player area 102 of FIG. 4, with this area being representative of any one of the player's areas of the "field".
Behind each slot 102s there exists a substantially rectilinear small mound 122 to prevent the ball from being detained behind the "player", and forcing the ball to the front of the player.
Along the entire perimeter of the "field" there extends a resilient fence 150 to prevent the ball from leaving the field.
In front of each "goal-area" there is located a respective slot 151, 152 whereat the "goal-keeper" associated to the electromagnetic actuator described in relation to FIG. 3 can be moved transversally to the goal-area to cover the "door" and prevent the scoring of a point by the opposing team.
Behind each of the short sides of the field, and near the corners of said field, there are located two control panels 160 (FIGS. 4 and 7) each panel comprising five small keys 161 arranged in a position comfortable for finger-tip operation, and a larger key 162 located close to the rear edge of the panel 160.
The small keys 161 energize the respective single-coil actuators associated to the "players" (FIG. 1) and each of the larger keys 162 energizes the respective left and right-hand coils of the double-coil actuator described in reference to FIG. 3.
The interconnection of the electromagnetic actuators activating the respective players to the keys on the control boards can be arranged, for instance, for the keys located on the left control board to activate the players of the left-hand side of the field, and vice-versa, or any other suitable combination.
The novelty of the "field" of the invention is in the arrangement of the elongated slots guiding the alternative movement of the players, said arrangement being such that each player is always in a convenient position for receiving, hitting and directing the ball to another player of the same team, or even intercepting the ball sent by a player from the other team, the novelty being also in the shaping and arrangement of the player's areas surrounding each of the respective slots. These areas always direct the ball towards the slot and the front of the respective player.
The frame of the electromagnetic actuator is mounted under the surface of the field, directly under the slot guiding the movement of the respective player, with the forward or energized movement of the player affixed to the vertical pin of the actuator facing the general direction of the opposing team's goal area. | An improvement in miniature toy football games in which figures representing players and goal-keepers move alternately along paths or trails provided on the surface of a plate which represents the playing field. The players and goal-keepers can be moved, as desired, by an operator pressing corresponding control keys arranged on a control panel. The surface of the playing field has an arrangement of undulations and cavities for guiding the ball towards the foot of a player. The players and goal-keepers are mounted on electromagnetic actuators in the form of a hollow magnet coil horizontally mounted on a frame. The coil has a sliding core linked to a lever arm for producing alternate movement of the players. The actuator is mounted under a slot guiding the movement of the players. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a flow measurement device for measuring the velocity of a fluid traveling through the turning sections of an air supply duct bend located between a forced draft fan and a secondary air windbox of a furnace.
2. Description of the Related Art
As a general rule, conventional fluid velocity measurement devices require uniform, linear duct regions to yield accurate air flow measurements. Straight, unobstructed ductwork having a length equivalent to several duct diameters, preceding the measurement device location, is required to ensure that proper fluid flow conditions exist at the measurement location. Unfortunately, some air duct systems contain no such regions, and any measurement taken in those systems will be less than accurate.
The use of turning vanes in rectangular elbow ducts to improve air flow through a bend is known. The usefulness of turning vanes for limiting pressure drops in a bend and for improving airflow through the bend is described at page 3-13 of Steam/Its Generation And Use (40th Ed.) which has been published by The Babcock & Wilcox Company. The effect of the vanes is to increase the velocity and reduce pressure drop through the bend. Turning vanes, however, are generally thin and occupy little cross-sectional area.
Examples of duct guide vanes can be found in several U.S. patents.
U.S. Pat. No. 3,405,737 to Harper discloses a plurality of double vanes attached perpendicular to a rail, which is connected to the opposite corners of a duct bend. The vanes are situated in the middle of the duct. The vanes extend between the top of the duct bend and the rail, forming channels between their concave and convex surfaces parallel to the duct bend.
U.S. Pat. No. 4,919,170 to Kallinich discloses a similar configuration to Harper. The flow guide elements of the Kallinich '170 patent are thin sheets oriented parallel to the duct bend. The flow guide elements in Kallinich are shorter at the inner corner of the duct bend than at the outer duct bend. The flow guides of the Kallinich '170 patent are disclosed to be used in a flue located between a power plant boiler and a flue gas-cleaning plant. However, the invention of Kallinich '170 is different from that of the present invention because the guides are thin.
The known corner foils are used primarily for directing air through a duct rather than channeling it into discrete flows for measurement. Also, the known corner foils attempt to reduce pressure changes and to maintain the same flow through duct bends. Many of the corner foils are continuous curves and therefore, do not provide straight segments between them, as required for accurate airflow measurements.
SUMMARY OF THE INVENTION
It is therefore, a primary object of the present invention to provide a suitable region in the bending sections of furnace ductwork for taking accurate pressure measurements in order to determine the velocity of the fluid flowing through the duct.
Accordingly, the proposed invention provides an apparatus for creating an acceptable flow environment in turning sections of a secondary air ductwork system. Means are provided for creating a region containing the proper fluid flow conditions. The means create regions in the turning sections, having increased fluid velocity which is suitable for obtaining accurate measurements of the fluid flow through the duct work.
The means comprises a plurality of segmented air foils which are placed across the width of a rectangular duct. The air foils have discrete segments which create straight channels between the air foils and the duct walls. Additionally, in one embodiment, a small plate is provided between one of the air foils and the inner duct wall to further straighten the fluid flow through the channel. The air foils are tapered more at the leading edge facing the fluid flow than at the trailing edge, where the fluid flow is allowed to expand back to the full width of the duct.
Apparatus for measuring the fluid flow is located in the straight channel regions between the air foils. The measurement apparatus may be oriented in any known manner most beneficial in obtaining an accurate measurement. The measurement apparatus is used to obtain a measurement of the fluid pressure in these regions, which can be used to determine the fluid velocity in the duct.
The pressure sensing device, senses both static and dynamic pressures of the fluid within the straight channel regions of the duct and transmits the magnitude of the pressure to another device such as a pressure transmitter which is capable of measuring the pressure differential. From the pressure transmitter, the information is relayed to a device capable of making calculations from the information and then displaying the fluid velocity based on the calculations.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a plane view of a ductwork bend incorporating the present invention; and
FIG. 2 is a sectional view taken along line 2--2 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in which like numerals are used to refer to the same or similar elements, FIG. 1 shows a section of a duct bend 10. The duct bend 10 is formed by inner duct wall 12 and outer duct wall 14, which are substantially parallel to each other. However, inner duct wall 12 has a arcuate shape, while outer duct wall 14 has a straight, flattened segment in between arcuate portions which forms the bend in the duct wall. The inner and outer duct walls 12, 14 are airtightly joined by duct side walls 16 (not shown in FIG. 1).
Inside duct bend 10 are first corner air foil 20, second corner air foil 22 and inner corner air foil 24. The air foils 20, 22 and 24 are substantially equally spaced between inner duct wall 12 and outer duct wall 14. The air foils 20, 22, 24 extend across the width of the duct bend 10 and have outer channel 50, middle channel 52 and inner channel 54 between them.
The first and second air foils 20 and 22 have leading edges 21 and 23 respectively, which are more tapered and elongated than their trailing edges 25 and 26 respectively. The air foils substantially reduce the total volume within the duct through which air passing through the duct may flow. The air is forced into the channels 50, 52, 54, where the pressure increase may be measured at pressure measurement points 40, shown within channels 50, 52, 54. Pressure measurement points 40 are connected to any known pressure measurement device (not shown) which can transmit the measurements to a processing and display device.
Also, thin plate 30 may be located within channel 54. The plate 30 is to further assist in straightening the air flow through channel 54, created by second corner air foil 22 and inner corner air foil 24.
Turning to FIG. 2, the channels 50, 52 and 54 created by the corner air foils 20, 22 and 24 can be seen to extend across the width of the duct bend 10. This view shows the leading edge ends of the foils 20, 22 and 24 and channels 50, 52 and 54. The foils are located essentially equidistantly between outer duct wall 14 and inner duct wall 12. The corner air foils 20, 22 are securely connected to side walls 16.
In a preferred shape for the first and second corner air foils, the leading edges 21 and 23 are created by a tapered section which has a length which is approximately 1/4 of the duct height. The duct height is the shortest distance between the inner duct wall 12 and the outer duct wall 14. Trailing edges 25 and 26 of the corner foils 20 and 22, are formed by a taper having a length which is approximately 1/8 of the height of the duct 10.
The middle sections of the air foils 20 and 22 can be of different widths depending on the desired size of the channels between them. One possible set of values for the width, however, is 1/5 the height of the duct for both corner foils 20 and 22. Inner corner air foil 24, which is securely fixed to inner duct wall 12, has a thickness which is equal to about 1/10 of the height of the duct.
Each of the corner air foils has a substantially straight section between the leading edges 21, 23 and the trailing edges 25, 26 having a length proportional to the length of the straight section of outer duct wall 14. In a preferred embodiment, the straight channel segments of the air foils 20, 22, 24 lie within an angle formed by lines extending between the ends of the straight section of the outer duct wall 14 and the center of a circle on which the arcuate portion of the inner duct wall 12 lies.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | An arrangement of air foils in a duct bend for channeling an air flow through the duct in a manner which enhances the accuracy of pressure measurements taken at one or more points in the channels formed in the duct between the air foils. | 5 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/835,316, filed Aug. 7, 2007, now abandoned, which is a continuation of U.S. patent application Ser. No. 11/000,375, filed Dec. 1, 2004, now U.S. Pat. No. 7,269,587, which is a continuation of U.S. patent application Ser. No. 09/895,174, filed Jul. 2, 2001, now U.S. Pat. No. 7,058,628, which is a continuation of U.S. patent application Ser. No. 09/004,827, filed Jan. 9, 1998, now U.S. Pat. No. 6,285,999, which claims priority from U.S. provisional patent application No. 60/035,205 filed Jan. 10, 1997, which are all incorporated herein by reference.
STATEMENT REGARDING GOVERNMENT SUPPORT
This invention was supported in part by the National Science Foundation grant number IRI-9411306-4. The Government has certain rights in the invention.
FIELD OF THE INVENTION
This invention relates generally to techniques for analyzing linked databases. More particularly, it relates to methods for assigning ranks to nodes in a linked database, such as any database of documents containing citations, the world wide web or any other hypermedia database.
BACKGROUND OF THE INVENTION
Due to the developments in computer technology and its increase in popularity, large numbers of people have recently started to frequently search huge databases. For example, internet search engines are frequently used to search the entire world wide web. Currently, a popular search engine might execute over 30 million searches per day of the indexable part of the web, which has a size in excess of 500 Gigabytes. Information retrieval systems are traditionally judged by their precision and recall. What is often neglected, however, is the quality of the results produced by these search engines. Large databases of documents such as the web contain many low quality documents. As a result, searches typically return hundreds of irrelevant or unwanted documents which camouflage the few relevant ones. In order to improve the selectivity of the results, common techniques allow the user to constrain the scope of the search to a specified subset of the database, or to provide additional search terms. These techniques are most effective in cases where the database is homogeneous and already classified into subsets, or in cases where the user is searching for well known and specific information. In other cases, however, these techniques are often not effective because each constraint introduced by the user increases the chances that the desired information will be inadvertently eliminated from the search results.
Search engines presently use various techniques that attempt to present more relevant documents. Typically, documents are ranked according to variations of a standard vector space model. These variations could include (a) how recently the document was updated, and/or (b) how close the search terms are to the beginning of the document. Although this strategy provides search results that are better than with no ranking at all, the results still have relatively low quality. Moreover, when searching the highly competitive web, this measure of relevancy is vulnerable to “spamming” techniques that authors can use to artificially inflate their document's relevance in order to draw attention to it or its advertisements. For this reason search results often contain commercial appeals that should not be considered a match to the query. Although search engines are designed to avoid such ruses, poorly conceived mechanisms can result in disappointing failures to retrieve desired information.
Hyperlink Search Engine, developed by IDD Information Services, (http://rankdex.gari.com/) uses backlink information (i.e., information from pages that contain links to the current page) to assist in identifying relevant web documents. Rather than using the content of a document to determine relevance, the technique uses the anchor text of links to the document to characterize the relevance of a document. The idea of associating anchor text with the page the text points to was first implemented in the World Wide Web Worm (Oliver A. McBryan, GENVL and WWWW: Tools for Taming the Web, First International Conference on the World Wide Web, CERN, Geneva, May 25-27, 1994). The Hyperlink Search Engine has applied this idea to assist in determining document relevance in a search. In particular, search query terms are compared to a collection of anchor text descriptions that point to the page, rather than to a keyword index of the page content. A rank is then assigned to a document based on the degree to which the search terms match the anchor descriptions in its backlink documents.
The well known idea of citation counting is a simple method for determining the importance of a document by counting its number of citations, or backlinks. The citation rank r(A) of a document which has n backlink pages is simply
r ( A )= n.
In the case of databases whose content is of relatively uniform quality and importance it is valid to assume that a highly cited document should be of greater interest than a document with only one or two citations. Many databases, however, have extreme variations in the quality and importance of documents. In these cases, citation ranking is overly simplistic. For example, citation ranking will give the same rank to a document that is cited once on an obscure page as to a similar document that is cited once on a well-known and highly respected page.
SUMMARY
Various aspects of the present invention provide systems and methods for ranking documents in a linked database. One aspect provides an objective ranking based on the relationship between documents. Another aspect of the invention is directed to a technique for ranking documents within a database whose content has a large variation in quality and importance. Another aspect of the present invention is to provide a document ranking method that is scalable and can be applied to extremely large databases such as the world wide web. Additional aspects of the invention will become apparent in view of the following description and associated figures.
The present invention achieves the above objects by taking advantage of the linked structure of a database to assign a rank to each document in the database, where the document rank is a measure of the importance of a document. Rather than determining relevance from the intrinsic content of a document, or from the anchor text of backlinks to the document, the present method determines importance from the extrinsic relationships between documents. Intuitively, a document should be important (regardless of its content) if it is highly cited by other documents. Not all citations, however, are of equal significance. A citation from an important document is more important than a citation from a relatively unimportant document. Thus, the importance of a page, and hence the rank assigned to it, should depend not just on the number of citations it has, but on the importance of the citing documents as well. This implies a recursive definition of rank: the rank of a document is a function of the ranks of the documents which cite it. The ranks of documents may be calculated by an iterative procedure on a linked database.
Because citations, or links, are ways of directing attention, the important documents correspond to those documents to which the most attention is directed. Thus, a high rank indicates that a document is considered valuable by many people or by important people. Most likely, these are the pages to which someone performing a search would like to direct his or her attention. Looked at another way, the importance of a page is directly related to the steady-state probability that a random web surfer ends up at the page after following a large number of links. Because there is a larger probability that a surfer will end up at an important page than at an unimportant page, this method of ranking pages assigns higher ranks to the more important pages.
In one aspect of the invention, a computer implemented method is provided for calculating an importance rank for N linked nodes of a linked database. The method comprises the steps of:
(a) selecting an initial N-dimensional vector p 0 ; (b) computing an approximation p n to a steady-state probability p ∞ in accordance with the equation p n =A n p 0 , where A is an N×N transition probability matrix having elements A[i][j] representing a probability of moving from node i to node j; and (c) determining a rank r[k] for a node k from a k th component of p n .
In a preferred embodiment, the matrix A is chosen so that an importance rank of a node is calculated, in part, from a weighted sum of importance ranks of backlink nodes of the node, where each of the backlink nodes is weighted in dependence upon the total number of links in the backlink node. In addition, the importance rank of a node is calculated, in part, from a constant α representing the probability that a surfer will randomly jump to the node. The importance rank of a node can also be calculated, in part, from a measure of distances between the node and backlink nodes of the node. The initial N-dimensional vector p 0 may be selected to represent a uniform probability distribution, or a non-uniform probability distribution which gives weight to a predetermined set of nodes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of the relationship between three linked hypertext documents according to the invention.
FIG. 2 is a diagram of a three-document web illustrating the rank associated with each document in accordance with the present invention.
FIG. 3 is a flowchart of one implementation of the invention.
DETAILED DESCRIPTION
Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the claimed invention. For support in reducing the present invention to practice, the inventor acknowledges Sergey Brin, Scott Hassan, Rajeev Motwani, Alan Steremberg, and Terry Winograd.
A linked database (i.e. any database of documents containing mutual citations, such as the world wide web or other hypermedia archive, a dictionary or thesaurus, and a database of academic articles, patents, or court cases) can be represented as a directed graph of N nodes, where each node corresponds to a web page document and where the directed connections between nodes correspond to links from one document to another. A given node has a set of forward links that connect it to children nodes, and a set of backward links that connect it to parent nodes. FIG. 1 shows a typical relationship between three hypertext documents A, B, and C. As shown in this particular figure, the first links in documents B and C are pointers to document A. In this case we say that B and C are backlinks of A, and that A is a forward link of B and of C. Documents B and C also have other forward links to documents that are not shown.
Although the ranking method of the present invention is superficially similar to the well known idea of citation counting, the present method is more subtle and complex than citation counting and gives far superior results. In a simple citation ranking, the rank of a document A which has n backlink pages is simply
r ( A )= n.
According to one embodiment of the present method of ranking, the backlinks from different pages are weighted differently and the number of links on each page is normalized. More precisely, the rank of a page A is defined according to the present invention as
r ( A ) = α N + ( 1 - α ) ( r ( B 1 ) B 1 + … + r ( B n ) B n ) ,
where B 1 , . . . , B n are the backlink pages of A, r(B 1 ), . . . , r(B n ) are their ranks, |B 1 |, . . . , |B n | are their numbers of forward links, and α is a constant in the interval [0,1], and N is the total number of pages in the web. This definition is clearly more complicated and subtle than the simple citation rank. Like the citation rank, this definition yields a page rank that increases as the number of backlinks increases. But the present method considers a citation from a highly ranked backlink as more important than a citation from a lowly ranked backlink (provided both citations come from backlink documents that have an equal number of forward links). In the present invention, it is possible, therefore, for a document with only one backlink (from a very highly ranked page) to have a higher rank than another document with many backlinks (from very low ranked pages). This is not the case with simple citation ranking.
The ranks form a probability distribution over web pages, so that the sum of ranks over all web pages is unity. The rank of a page can be interpreted as the probability that a surfer will be at the page after following a large number of forward links. The constant α in the formula is interpreted as the probability that the web surfer will jump randomly to any web page instead of following a forward link. The page ranks for all the pages can be calculated using a simple iterative algorithm, and corresponds to the principal eigenvector of the normalized link matrix of the web, as will be discussed in more detail below.
In order to illustrate the present method of ranking, consider the simple web of three documents shown in FIG. 2 . For simplicity of illustration, we assume in this example that r=0. Document A has a single backlink to document C, and this is the only forward link of document C, so
r ( A )= r ( C ).
Document B has a single backlink to document A, but this is one of two forward links of document A, so
r ( B )= r ( A )/2.
Document C has two backlinks. One backlink is to document B, and this is the only forward link of document B. The other backlink is to document A via the other of the two forward links from A.
Thus
r ( C )= r ( B )+ r ( A )/2.
In this simple illustrative case we can see by inspection that r(A)=0.4, r(B)=0.2, and r(C)=0.4. Although a typical value for α is ˜0.1, if for simplicity we set α=0.5 (which corresponds to a 50% chance that a surfer will randomly jump to one of the three pages rather than following a forward link), then the mathematical relationships between the ranks become more complicated. In particular, we then have
r ( A )=1/6 +r ( C )/2,
r ( B )=1/6 +r ( A )/4, and
r ( C )=1/6 +r ( A )/4 +r ( B )/2.
The solution in this case is r(A)=14/39, r(B)=10/39, and r(C)=15/39.
In practice, there are millions of documents and it is not possible to find the solution to a million equations by inspection. Accordingly, in the preferred embodiment a simple iterative procedure is used. As the initial state we may simply set all the ranks equal to 1/N. The formulas are then used to calculate a new set of ranks based on the existing ranks. In the case of millions of documents, sufficient convergence typically takes on the order of 100 iterations. It is not always necessary or even desirable, however, to calculate the rank of every page with high precision. Even approximate rank values, using two or more iterations, can provide very valuable, or even superior, information.
The iteration process can be understood as a steady-state probability distribution calculated from a model of a random surfer. This model is mathematically equivalent to the explanation described above, but provides a more direct and concise characterization of the procedure. The model includes (a) an initial N-dimensional probability distribution vector p 0 where each component p 0 [i] gives the initial probability that a random surfer will start at a node i, and (b) an N×N transition probability matrix A where each component A[i][j] gives the probability that the surfer will move from node i to node j. The probability distribution-of the graph after the surfer follows one link is p 1 =Ap 0 , and after two links the probability distribution is p 2 =Ap 1 =A 2 p 0 . Assuming this iteration converges, it will converge to a steady-state probability
p
∞
=
lim
n
→
∞
A
n
p
0
which is a dominant eigenvector of A. The iteration circulates the probability through the linked nodes like energy flows through a circuit and accumulates in important places. Because pages with no links occur in significant numbers and bleed off energy, they cause some complication with computing the ranking. This complication is caused by the fact they can add huge amounts to the “random jump” factor. This, in turn, causes loops in the graph to be highly emphasized which is not generally a desirable property of the model. In order to address this problem, these childless pages can simply be removed from the model during the iterative stages, and added back in after the iteration is complete. After the childless pages are added back in, however, the same number of iterations that was required to remove them should be done to make sure they all receive a value. (Note that in order to ensure convergence, the norm of p i must be made equal to 1 after each iteration.) An alternate method to control the contribution of the childless nodes is to only estimate the steady state by iterating a small number of times.
The rank r[i] of a node i can then be defined as a function of this steady-state probability distribution. For example, the rank can be defined simply by r[i]=p ∞ [i]. This method of calculating rank is mathematically equivalent to the iterative method described first. Those skilled in the art will appreciate that this same method can be characterized in various different ways that are mathematically equivalent. Such characterizations are obviously within the scope of the present invention. Because the rank of various different documents can vary by orders of magnitude, it is convenient to define a logarithmic rank
r [ i ] = log p ∞ [ i ] min k ∈ [ 1 , N ] { p ∞ [ k ] }
which assigns a rank of 0 to the lowest ranked node and increases by 1 for each order of magnitude in importance higher than the lowest ranked node.
FIG. 3 shows one embodiment of a computer implemented method for calculating an importance rank for N linked nodes of a linked database. At a step 101 , an initial N-dimensional vector p 0 is selected. An approximation p n , to a steady-state probability p ∞ in accordance with the equation p n =A n p 0 is computed at a step 103 . Matrix A can be an N×N transition probability matrix having elements A[i][j] representing a probability of moving from node i to node j. At a step 105 , a rank r[k] for node k from a k th component of p n is determined.
In one particular embodiment, a finite number of iterations are performed to approximate p ∞ . The initial distribution can be selected to be uniform or non-uniform. A uniform distribution would set each component of p 0 equal to 1/N. A non-uniform distribution, for example, can divide the initial probability among a few nodes which are known a priori to have relatively large importance. This non-uniform distribution decreases the number of iterations required to obtain a close approximation to p ∞ and also is one way to reduce the effect of artificially inflating relevance by adding unrelated terms.
In another particular embodiment, the transition matrix A is given by
A = α N 11 + ( 1 - α ) B ,
where 11 is an N×N matrix consisting of all 1s, α is the probability that a surfer will jump randomly to any one of the N nodes, and B is a matrix whose elements B[i][j] are given by
B [ i ] [ j ] = { 1 n i if node i points to node j 0 otherwise ,
where n i is the total number of forward links from node i. The (1−α) factor acts as a damping factor that limits the extent to which a document's rank can be inherited by children documents. This models the fact that users typically jump to a different place in the web after following a few links. The value of α is typically around 15%. Including this damping is important when many iterations are used to calculate the rank so that there is no artificial concentration of rank importance within loops of the web. Alternatively, one may set α=0 and only iterate a few times in the calculation.
Consistent with the present invention, there are several ways that this method can be adapted or altered for various purposes. As already mentioned above, rather than including the random linking probability α equally among all nodes, it can be divided in various ways among all the sites by changing the 11 matrix to another matrix. For example, it could be distributed so that a random jump takes the surfer to one of a few nodes that have a high importance, and will not take the surfer to any of the other nodes. This can be very effective in preventing deceptively tagged documents from receiving artificially inflated relevance. Alternatively, the random linking probability could be distributed so that random jumps do not happen from high importance nodes, and only happen from other nodes. This distribution would model a surfer who is more likely to make random jumps from unimportant sites and follow forward links from important sites. A modification to avoid drawing unwarranted attention to pages with artificially inflated relevance is to ignore local links between documents and only consider links between separate domains. Because the links from other sites to the document are not directly under the control of a typical web site designer, it is then difficult for the designer to artificially inflate the ranking. A simpler approach is to weight links from pages contained on the same web server less than links from other servers. Also, in addition to servers, internet domains and any general measure of the distance between links could be used to determine such a weighting.
Additional modifications can further improve the performance of this method. Rank can be increased for documents whose backlinks are maintained by different institutions and authors in various geographic locations. Or it can be increased if links come from unusually important web locations such as the root page of a domain.
Links can also be weighted by their relative importance within a document. For example, highly visible links that are near the top of a document can be given more weight. Also, links that are in large fonts or emphasized in other ways can be given more weight. In this way, the model better approximates human usage and authors' intentions. In many cases it is appropriate to assign higher value to links coming from pages that have been modified recently since such information is less likely to be obsolete.
Various implementations of the invention have the advantage that the convergence is very fast (a few hours using current processors) and it is much less expensive than building a full-text index. This speed allows the ranking to be customized or personalized for specific users. For example, a user's home page and/or bookmarks can be given a large initial importance, and/or a high probability of a random jump returning to it. This high rating essentially indicates to the system that the person's homepage and/or bookmarks does indeed contain subjects of importance that should be highly ranked. This procedure essentially trains the system to recognize pages related to the person's interests.
The present method of determining the rank of a document can also be used to enhance the display of documents. In particular, each link in a document can be annotated with an icon, text, or other indicator of the rank of the document that each link points to. Anyone viewing the document can then easily see the relative importance of various links in the document.
The present method of ranking documents in a database can also be useful for estimating the amount of attention any document receives on the web since it models human behavior when surfing the web. Estimating the importance of each backlink to a page can be useful for many purposes including site design, business arrangements with the backlinkers, and marketing. The effect of potential changes to the hypertext structure can be evaluated by adding them to the link structure and recomputing the ranking.
Real usage data, when available, can be used as a starting point for the model and as the distribution for the alpha factor. This can allow this ranking model to fill holes in the usage data, and provide a more accurate or comprehensive picture. Thus, although this method of ranking does not necessarily match the actual traffic, it nevertheless measures the degree of exposure a document has throughout the web.
Another application and embodiment of the present invention is directed to enhancing the quality of results from web search engines. In this application of the present invention, a ranking method according to the invention is integrated into a web search engine to produce results far superior to existing methods in quality and performance. A search engine employing a ranking method of the present invention provides automation while producing results comparable to a human maintained categorized system. In this approach, a web crawler explores the web and creates an index of the web content, as well as a directed graph of nodes corresponding to the structure of hyperlinks. The nodes of the graph (i.e., pages of the web) are then ranked according to importance as described above in connection with various exemplary embodiments of the present invention.
The search engine is used to locate documents that match the specified search criteria, either by searching full text, or by searching titles only. In addition, the search can include the anchor text associated with backlinks to the page. This approach has several advantages in this context. First, anchors often provide more accurate descriptions of web pages than the pages themselves. Second, anchors may exist for images, programs, and other objects that cannot be indexed by a text-based search engine. This also makes it possible to return web pages which have not actually been crawled. In addition, the engine can compare the search terms with a list of its backlink document titles. Thus, even though the text of the document itself may not match the search terms, if the document is cited by documents whose titles or backlink anchor text match the search terms, the document will be considered a match. In addition to or instead of the anchor text, the text in the immediate vicinity of the backlink anchor text can also be compared to the search terms in order to improve the search.
Once a set of documents is identified that match the search terms, the list of documents is then sorted with high ranking documents first and low ranking documents last. The ranking in this case is a function which combines all of the above factors such as the objective ranking and textual matching. If desired, the results can be grouped by category or site as well.
It will be clear to one skilled in the art that the above embodiments may be altered in many ways without departing from the scope of the invention. Accordingly, the scope of the invention should be determined by the following claims and their legal equivalents. | A method may include identifying a linked document that is linked to by a group of linking documents; identifying links between the linking documents and the linked document; assigning a weight to each of the identified links; and determining a score for the linked document based on the identified links between the linking documents and the linked document, and the weights assigned to each of the identified links. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national stage under 35 U.S.C. 371 of International Application PCT/CA2011/001387, filed on Dec. 22, 2011 (currently pending). International Application PCT/CA2011/001387 cites the priority of U.S. Patent Application 61/460,195, filed Dec. 27, 2010.
FIELD OF THE INVENTION
The present invention relates to the drilling and stimulating of subterranean rock formations for the recovery of hydrocarbon and natural gas resources. In particular, the present invention relates to a method of fracture treating a wellbore while the drilling operation is underway.
BACKGROUND
Subterranean reservoir rock formations that contain hydrocarbons and gases are often, if not usually, horizontal in profile. It was therefore of immense economic value and a great benefit to society when modern drilling techniques were developed that could create horizontal wellbores from a vertical well over a distance to gain access to a larger portion of hydrocarbon and natural gas resources in a reservoir.
A problem to overcome, however, was that such horizontal reservoirs (for instance, shale formations), are generally quite tight and compressed in nature, meaning that they often don't contain natural fractures of sufficient porosity and permeability within the formation through which hydrocarbons and gas can readily flow into the well at economic rates. Engineers, however, were able to develop methodologies whereby rock formations can be “perfed” (perforated) and “fracked” (fractured) to create pathways in the rock formations through which hydrocarbons and gas can much more readily flow to the well.
While such fracking has led to a great increase in the amount of hydrocarbons and gas that can be readily recovered from a formation, engineers found that it was important to be able to isolate one fracture from another so that the same part of the well was not being repeatedly fractured. Repeated fracturing can cause rock chips and fine rock particles to enter cracks and pore space, thereby reducing the porosity and permeability of the fracked area into the well. The same is true for vertical or deviated wells.
In the known methodology, drilling, and perfing and fracking rock formations involves separate operations. In particular, the well is drilled first, and then the drilling rig is moved off location before a fracturing “spread” is moved on to the location to perf and frac the wellbore for the subsequent recovery of hydrocarbon or natural gas resources. The timing between the drilling of the well and the fracture treatment of the same well can vary from immediately thereafter to as much as 18 months depending on the availability of frac equipment which is in high demand. There are therefore several inefficiencies in the known methods of resource recovery.
It is useful to more fully discuss the conventional drilling and fracking methodology in order to assist in distinguishing the method of the present invention.
Conventional Drilling
A drill bit(s) is mounted on the end of a drill pipe, and a mixture of water and additives (“mud”) is pumped into the hole to cool the bit and flush the cuttings to the surface as the drill bit(s) grinds away at the rock. This mud generally cakes on the walls of the wellbore, which assists in keeping the well intact. The hole is generally drilled to just under the deepest fresh water reservoir near the surface, where the drill pipe is then first removed. Surface casing is then inserted into the drilled hole to a point below the water reservoir in order to isolate the fresh water zone. Cement is subsequently pumped down the casing, exits through an opening called a shoe at the bottom of the casing and wellbore, and is then forced up between the outside of the casing and the hole, effectively sealing off the wellbore from the fresh water. This cementing process prevents contamination of the freshwater aquifers. The drill pipe is then lowered back down the hole to drill through the plug and cement and continue the vertical section of the well. At a certain depth above the point where a horizontal well is desired (the “kick-off point” or “KOP”), the well will slowly begin to be drilled on a curve to the point where a horizontal section can be drilled. The KOP is often located approximately 220 meters above the planned horizontal leg. Up to this point, the process is the same as drilling a vertical well.
Once the KOP is reached, the pipe and bit are pulled out of the hole and a down hole drilling motor with measurement drilling instruments is lowered back into the hole to begin the angle building process. In general, it takes approximately 350 m of drilling to make the curve from the KOP to where the wellbore becomes horizontal (assuming an 8° angle building process, for instance). Then, drilling begins on the “lateral”, the well's horizontal section.
When the targeted horizontal drilling distance is reached on the lateral, the drill bit and pipe are removed from the wellbore. Production casing is then inserted into the full length of the wellbore. Cement is again pumped down the casing and out through the hole in the casing shoe, forcing the cement up between the outside of the casing and the wall of the hole, thus filling the “annulus”, or open space. At this point, the drilling rig is no longer needed so this equipment is moved off-site and a well head is installed. The fracturing or service crew then moves its equipment on-site to prepare the well for production and the recovery of hydrocarbon and gas resources.
Conventional Perfing and Fracking of the Wellbore
The first step in the known method is to perf the casing. In this respect, a perforating gun is lowered by wire line into the casing to the targeted section of the horizontal leg (i.e. in general, to the end of the lateral so that the process can work back along the horizontal leg from the “toe” to the “heel” of the wellbore). An electrical current is sent down the wire line to the perf gun, which sets off a charge that shoots small evenly-spaced holes through the casing and cement and out a short distance into the rock formation (often shale). This causes fractures in the rock formation, but is generally not sufficient in itself to create proper fairways through which hydrocarbons or gas can readily flow into the wellbore due to the tight or compressed nature of the rock formation (as previously stated, compressed reservoirs do not generally contain natural fractures and therefore hydrocarbons or gas cannot be produced economically without additional manipulation). As a result, a further step is needed to increase the porosity and permeability of the rock by providing more significant pathways through which the hydrocarbons or gas can flow more readily. To do this, the perf gun is removed from the hole, and the well then needs to be “fracked” to create proper fairways.
Fracking (or fracing) is the process of propagating the fracture in the rock layer caused by the perforation in the formation from the perf gun. In this respect, it is hydraulic fracturing that is usually undertaken, which is the process whereby a slurry of, for example, mainly water, and some sand and additives are pumped into the wellbore and down the casing under extremely high pressure to break the rock and propagate the fractures (sufficient enough to exceed the fracture gradient of the rock). In particular, as this mixture is forced out through the vertical perforations caused by the perf gun and into the surrounding rock, the pressure causes the rock to fracture. Such fracturing creates a fairway, often a tree-like dendritic fairway, that connects the reservoir to the well and allows the released hydrocarbons or gas to flow much more readily to the wellbore. Once the injection has stopped, often a solid proppant (e.g. silica sand, resin-coated sand, man-made ceramics) is added to the fluid and injected to keep the fractures open. The propped fractures are permeable enough to allow the flow of hydrocarbons or gas to the well.
In order for the next section of the horizontal leg to be perforated and fracked (i.e. multi-stage fracking from the “toe” all along to the “heel” of the horizontal leg), a temporary plug is placed at the nearest end of the first-stage frac to close off and isolate the already perforated and fracked section of the wellbore. The process of perfing, fracking, and plugging is then repeated numerous times until the entire horizontal distance of the wellbore is covered. Once such a process has been completed, the plugs are drilled out, allowing the hydrocarbons or gas to flow up the wellbore to a permanent wellhead for storage and distribution. Unfortunately, in this known method, a well operator is unable to determine whether any particular fracture treatment has been successful in increasing the porosity and permeability of the rock formation at a given location of the wellbore, whether the treatment is having a net positive or negative effect on overall flow of hydrocarbons or gas into the well, and whether a modification to the fracturing fluid/slurry, for example, would have produced better results.
Persons skilled in the art would be aware of other similar or related completion methodologies that have the same limitations. For instance, engineers may employ an open hole completion where no casing is cemented in place across the horizontal production leg. Pre-holed or slotted liners/casing may be employed across the production zone. Swellable/inflatable elastomer packers may be used, for instance, to provide zonal isolation and segregation, and zonal flow control of hydrocarbons or gas. Perfing may be accomplished by perforating tools or by a multiple sliding sleeve assembly, etc. Regardless, the methodologies operate in essentially the same manner—the operation proceeds from the “toe” of the well back to the “heel”, and the well operator is unable to determine whether any particular fracture treatment has been successful in increasing the porosity and permeability of the rock formation at any given location of the wellbore, whether the treatment is having a net positive or negative effect on overall flow of hydrocarbons or gas into the well, and whether a modification to the fracturing fluid/slurry, for example, would have produced better results.
A method that would allow for the creation of fracture treatments into a wellbore while the drilling operation is under way would overcome several problems and inefficiencies associated with the known hydrocarbon and gas recovery process in the oil and gas industries.
SUMMARY OF THE INVENTION
The method of the present invention involves placing fracture treatments into a wellbore while the drilling operation is still under way (drilling ahead). The fracture treatment is bounded in the open hole on one side by the current end of the hole and on the other side by a temporary pack off isolation fluid that has been introduced to the well by way of either pumping down the existing drill string or by pumping down a separate frac string. In particular, the drill string or frac string remains in the wellbore, and the annulus between same and the wellbore is packed off with the temporary isolation fluid/material. The objective is to place the frac in the reservoir and flow it back very quickly after placement, thus increasing the chances of flowing back harmful formation damaging materials and increasing the relative productivity of the newly placed fracture treatment (compared to conventionally placed fracs).
Drilling then continues (with hydrocarbon and gas resources being recoverable even at this early stage) and fractures can be placed as closely to one another as practical. This is only limited by the effectiveness of the isolation fluid/material given the pressure created at the fracture site (called fracture initiation pressure) in the context of the subterranean formation at issue—the better the isolation fluid/material works, the shorter the required distance between fracture intervals. In this manner, multi-stage fractures can be placed in a wellbore as the well is drilled ahead, each one contributing cumulatively as the wellbore length is increased.
The net effect of the method of the present invention is that the well operator is able to determine in real time if a fracture treatment has been successful, including whether the fracture treatment composition is sufficient/should be changed, and whether this is having a net positive or negative effect on overall flow of the hydrocarbons or gas into the well. Based on the composition of the inflow up the well, the operator may determine, for instance, that the frac treatment has been effective or may determine that a different fracturing fluid/slurry should be employed for subsequent frac treatments based on the rock formation encountered. This is to be distinguished from conventional fracking techniques where there is no real time feedback, no way to know whether a proper fracturing fluid/slurry was used at a particular stage/site, and no way for an operator to know what must be done to improve performance.
Finally, this “Frac Ahead” process allows the operator to place multiple fractures (much like the dendritic pattern observed in leaf patterns) in multi lateral wellbores, thereby increasing swept reservoir volume to a previously unattainable level.
According to one aspect of the present invention, there is provided a method of drilling and completing a wellbore in a subterranean formation for the recovery of hydrocarbon or natural gas resources comprising the steps of:
(i) drilling an intermediate wellbore in a subterranean formation by means of a drill string; (ii) inserting a frac string into the wellbore and pumping into the wellbore through an opening in the frac string an isolation fluid that is sufficient to withstand fracture initiation pressure; (iii) pumping into the wellbore through an opening in the frac string a frac fluid at a pressure sufficient to create fractures in the subterranean formation in the vicinity of the end of the frac string; (iv) removing the frac string from the wellbore; (v) inserting the drill string into the wellbore and through the isolation fluid to flow any residual frac fluid and the isolation fluid back out of the wellbore; and (vi) extending the wellbore by means of the drill string,
whereby hydrocarbon or natural gas resources may flow from the fractures into the wellbore for the recovery thereof while drilling proceeds, and whereby steps (ii) to (vi) may be repeated throughout the entire length of the wellbore to create multi-fractured zones in the wellbore that cumulatively add to the recovery of hydrocarbon or natural gas resources.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of exemplary embodiments in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described, by way of example only, with reference to the attached figures, wherein:
FIG. 1 is a diagram showing the drilling of an intermediate hole;
FIG. 2 is a diagram showing an open wellbore before intermediate casing is inserted;
FIG. 3 is a diagram showing the insertion of intermediate casing into the wellbore;
FIG. 4 is a diagram showing the cementing of the intermediate casing in the wellbore;
FIG. 5 is a diagram showing the intermediate casing cemented in the wellbore;
FIG. 6 is a diagram showing the drilling out of the shoe in the intermediate casing;
FIG. 7 is a diagram showing the drilling of a first section beyond the intermediate casing;
FIG. 8 is a diagram showing the open first section of the wellbore;
FIG. 9 is a diagram showing the insertion of a frac string into the first section of the wellbore;
FIG. 10 is a diagram showing the pumping of isolation fluid from the frac string into the first section of the wellbore;
FIG. 11 is a diagram showing the pumping of frac fluid from the frac string into the first section of the wellbore;
FIG. 12 is a diagram showing fractures created in the subterranean formation from the frac treatment to the first section of the wellbore;
FIG. 13 is a diagram showing the removal of the frac string from the wellbore;
FIG. 14 is a diagram showing the insertion of the drill string through the isolation fluid in the first section of the wellbore;
FIG. 15 is a diagram showing the flow of hydrocarbons or gas from the fractures into the first section of the wellbore;
FIG. 16 is a diagram showing the drill string extending to the end of the first section of the wellbore;
FIG. 17 is a diagram showing the drilling ahead of a section of the wellbore;
FIG. 18 is a diagram showing the open second section of the wellbore before the frac string is inserted;
FIG. 19 is a diagram showing the insertion of a frac string into the second section of the wellbore;
FIG. 20 is a diagram showing the pumping of isolation fluid from the frac string into the second section of the wellbore;
FIG. 21 is a diagram showing the pumping of frac fluid from the frac string into the second section of the wellbore to create fractures in the subterranean formation;
FIG. 22 is a diagram showing the removal of the frac string from the wellbore;
FIG. 23 is a diagram showing the insertion of the drill string through the isolation fluid in the second section of the wellbore;
FIG. 24 is a diagram showing the drilling ahead of a third section of the wellbore;
FIG. 25 is a diagram showing the open third section of the wellbore before the frac string is inserted;
FIG. 26 is a diagram showing the insertion of a frac string into the third section of the wellbore;
FIG. 27 is a diagram showing the pumping of isolation fluid from the frac string into the third section of the wellbore;
FIG. 28 is a diagram showing the pumping of frac fluid from the frac string into the third section of the wellbore to create fractures in the subterranean formation;
FIG. 29 is a diagram showing the removal of the frac string from the wellbore;
FIG. 30 is a diagram showing the insertion of the drill string through the isolation fluid in the third section of the wellbore;
FIG. 31 is a diagram showing the drilling ahead of a fourth section of the wellbore while hydrocarbons or gas are flowing into the wellbore;
FIG. 32 is a diagram showing the flowing of hydrocarbons or gas from fractures in the first, second, and third sections into the wellbore;
FIG. 33 is a plan view of hypothetical fractures in a single leg horizontal wellbore;
FIG. 34 is a plan view of hypothetical fractures in a single leg horizontal wellbore with an overlay showing the swept reservoir area;
FIG. 35 is a plan view of a hypothetical dendritic wellbore configuration in a subterranean formation;
FIG. 36 is a plan view showing production/flow of hydrocarbons or gas from fractures into the dendritic wellbores;
FIG. 37 is a plan view of a hypothetical dual horizontal wellbore configuration;
FIG. 38 is a plan view of a hypothetical dual horizontal wellbore configuration with an overlay showing the swept reservoir area; and
FIG. 39 is a plan view showing production/flow of hydrocarbons or gas from fractures into the dual horizontal wellbore.
The same reference numerals are used in different figures to denote similar elements.
DETAILED DESCRIPTION
The method of the present invention is generally used in horizontal wells but can also be used on vertical or deviated wells.
In an exemplary embodiment, with reference to FIG. 1 , an intermediate wellbore 2 is drilled in a subterranean formation 4 using a conventional drill string 6 with a conventional drill bit 8 attached to the end thereof. The drill string 6 is then withdrawn from the intermediate wellbore 2 (see FIG. 2 ) and an intermediate casing 10 is run into the wellbore 2 (see FIG. 3 ). The space between the outside of casing 10 and the wellbore 2 is called the annulus 12 . With reference to FIG. 4 , suitable cement 14 is pumped into the casing 10 under high pressure where it exits the end of the casing 10 (known as the shoe 16 ) and fills in the annulus 12 . In this respect, casing 10 is generally cemented into place, such that the cement 14 generally fills the space both inside at least an end section (shoe joint) of casing 10 as well as the annulus 12 . FIG. 5 shows the casing 10 wherein the cement 14 is hardened in place such that the shoe 16 is closed off. A person skilled in the art to which the invention relates will understand, however, that the use of the casing 10 in the manner described above is optional as methods according to the present invention can also be applied to “mono-bore” wellbore configurations.
With reference to FIG. 6 , the drill string 6 is then run into the casing 10 and drills out the shoe 16 of the intermediate casing 10 . With reference to FIG. 7 , the drill string 6 then continues drilling a first section of the wellbore 2 (indicated generally at 18 ) extending from and beyond the intermediate wellbore 2 . The drill string 6 is then withdrawn (see FIG. 8 ) and a frac string 20 is run into the first section 18 (see FIG. 9 ).
With reference to FIG. 10 , an isolation fluid 22 is introduced into the first section 18 through openings in the frac string 20 to fill all or part of the first section 18 . The isolation fluid 22 is one which can withstand the pressure created at the fracture (called fracture initiation pressure) and that therefore does not allow significant movement of a fracturing fluid to another part of the well. The isolation fluid 22 can be a suitable gel, for example.
With reference to FIG. 11 , a fracturing fluid 24 is then pumped into the first section 18 through an opening 26 in the frac string 20 at a pressure sufficient to create fractures 28 (i.e. sufficient enough to exceed the fracture gradient of the rock) in the subterranean formation 4 in the vicinity of the end of the frac string 20 and the end of the first section 18 . The fracturing fluid 24 is often a slurry of, for example, mainly water, and some sand and additives, but can include any suitable fluid including but not limited to water, salt water, hydrocarbon, acid, methanol, carbon dioxide, nitrogen, foam, emulsions, etc. Such fracturing fluids are well known to persons skilled in the art. FIG. 12 shows a different perspective view of the fractures 28 (tree-like dendritic fairways) propogating throughout the formation 4 in the vicinity of the end of the frac string 20 .
With reference to FIG. 13 , the frac string 20 is then withdrawn and the drill string 6 is run to the end of the first section 18 through the isolation fluid 22 (see FIG. 14 ). The isolation fluid 22 is then “cleaned up” by rotating the bit 8 through and flowing it back out of the well through the annulus between the drill string 6 and the open hole and between the drill string and the intermediate casing 10 , along with drilled material being circulated to the surface (not shown) and production (hydrocarbons or gas 30 ) from the newly formed fractures 28 (see FIGS. 15 and 16 ). The drill string 6 is then moved ahead to the end of the first section 18 , and a second section (indicated generally at 32 ) is drilled to extend the wellbore 2 (see FIG. 17 ). In so doing, an operator can then perform multi-stage fracking while the wellbore is being drilled/extended by repeating the isolation and fracturing steps described above. It is important to note that at this time, hydrocarbons or gas 30 are flowing into the well, and are therefore recoverable at this stage, even while drilling proceeds. As a result, the well operator is able to determine in real time if the recent fracture treatment has been successful at this early stage, including determining the sufficiency of the fracture treatment composition, and whether the fracture treatment is having a net positive or negative effect on flow of the hydrocarbons or gas 30 . Based on the composition of the inflow up the well, an operator may determine, for instance, that a given frac treatment has been effective or may determine that a different fracturing fluid/slurry should be employed for subsequent frac treatments based on the rock formation encountered. This is to be distinguished from conventional fracking techniques where there is no real time feedback, no way to know whether the fracturing fluid/slurry used was effective, and no way for an operator to know what must be done to improve performance.
The repeated isolation and multi-stage fracturing steps are shown in FIGS. 18 to 32 . In particular, with reference to FIG. 18 , the drill string 6 is withdrawn from the wellbore (see FIG. 18 ) and a frac string 20 is run into the second section 32 (see FIG. 19 ). With reference to FIG. 20 , an isolation fluid 22 is introduced into the second section 32 through openings in the frac string 20 to fill all or part of the second section 32 . With reference to FIG. 21 , a fracturing fluid 24 is then pumped into the second section 32 through an opening in the frac string 20 at a pressure sufficient to create fractures 28 in the subterranean formation 4 in the vicinity of the end of the frac string 20 and near the end of the second section 32 . With reference to FIG. 22 , the frac string 20 is then withdrawn and, with reference to FIG. 23 , the drill string 6 is run to the end of the second section 32 through the isolation fluid 22 (not shown). The isolation fluid 22 is “cleaned up” by rotating the bit 8 through and flowing it back out of the well through the annulus between the drill string 6 and the open hole and between the drill string and the intermediate casing 10 , along with drilled material being circulated to the surface (not shown) and production (hydrocarbons or gas 30 ) from the newly formed fractures 28 . In particular, with reference to FIG. 24 (which shows the drilling/extension of a third section 34 of the wellbore 2 ), because hydrocarbons or gas 30 are now flowing into the well from fractures 28 from both the first section 18 and the second section 32 , as noted above, the well operator is able to determine in real time if the second fracture treatment has been successful at this early stage, including whether the fracture treatment composition should be changed, and whether such treatment is having a net positive or negative effect on overall flow of the hydrocarbons or gas 30 into the well. Based on the composition of the inflow up the well, the operator may determine, for instance, that the given frac treatment has been effective or may determine that a different fracturing fluid/slurry should be employed for subsequent frac treatments based on the rock formation encountered. Once again, this is to be distinguished from conventional fracking techniques where there is no real time feedback, no way to know whether a proper fracturing slurry was used at a particular stage/site, and no way for an operator to know what must be done to improve performance.
The repeated process then continues at FIG. 25 . The drill string 6 is withdrawn and a frac string 20 is run into the third section 34 (see FIG. 26 ). With reference to FIG. 27 , an isolation fluid 22 is introduced into the third section 34 through openings in the frac string 20 to fill all or part of the third section 34 . With reference to FIG. 28 , a fracturing fluid 24 is then pumped into the third section 34 through an opening in the frac string 20 at a pressure sufficient to create fractures 28 in the subterranean formation 4 in the vicinity of the end of the frac string 20 and near the end of the third section 34 . With reference to FIG. 29 , the frac string 20 is then withdrawn and, with reference to FIG. 30 , the drill string 6 is run to the end of the third section 34 through the isolation fluid 22 (not shown). The isolation fluid 22 is “cleaned up” by rotating the bit 8 through and flowing it back out of the well through the annulus between the drill string 6 and the open hole and between the drill string and the intermediate casing 10 , along with drilled material being circulated to the surface (not shown) and production (hydrocarbons or gas 30 ) from the newly formed fractures 28 . In particular, with reference to FIG. 31 (which shows the drilling/extension of a fourth section 36 of the wellbore 2 ), because hydrocarbons or gas 30 are now flowing into the well from fractures 28 from both the first section 18 , the second section 32 , and the third section 34 (see FIG. 32 ), the well operator can determine in real time if the third fracture treatment has been successful at this early stage, including whether the fracture treatment composition should be changed, and whether such change is having a net positive or negative effect on overall flow of hydrocarbons or gas 30 into the well. Based on the composition of the inflow up the well, the operator may determine, for instance, that the given frac treatment has been effective or may determine that a different fracturing fluid/slurry should be employed for subsequent frac treatments based on the rock formation encountered. Once again, this is to be distinguished from conventional fracking techniques where there is no real time feedback, no way to know whether a proper fracturing slurry was used at a particular stage/site, and no way for an operator to know what must be done to improve performance. A person skilled in the art would understand that such a process could continue further throughout the entire desired length of the wellbore.
In another exemplary embodiment (not shown), the process may proceed as shown in FIGS. 1 to 5 , however, at this stage a hybrid drill/frac string with a drill BHA on the end (not shown) is then run into the casing 10 , the shoe 16 is drilled out, and a first section 18 extending from and beyond the intermediate wellbore 2 is drilled (as in FIG. 7 ). The drill BHA part would then be disconnected from the hybrid drill/frac string and withdrawn back up to the surface through the string using a wireline or similar arrangement. An isolation fluid 22 is then introduced into the first section 18 through the hybrid drill/frac string to fill all or part of the first section 18 . The isolation fluid 22 is one which can, as stated previously, withstand the pressure created at the fracture (called fracture initiation pressure) and that therefore does not allow significant movement of a fracturing fluid to another part of the well. The isolation fluid 22 can be a suitable gel for example. A fracturing fluid 24 is then introduced through the hybrid drill/frac string into the first section 18 at a pressure sufficient to fracture the subterranean formation 4 in the vicinity of the end of the string, in a manner similar to that shown in FIG. 11 . The fracturing fluid can, once again, be a slurry of, for example, mainly water, and some sand and additives, but can include any suitable fluid including but not limited to water, salt water, hydrocarbon, acid, methanol, carbon dioxide, nitrogen, foam, emulsions, etc. The isolation fluid is cleaned up by flowing it back out of well through the hybrid drill/frac string annulus. The hybrid drill/frac string is then moved ahead and a second section beyond the first section is drilled to extend the wellbore. The isolation and fracturing steps described above can then be repeated.
FIG. 33 shows a plan view of a single leg horizontal wellbore 2 with fractures 28 propogated in a subterranean formation 4 in accordance with the methods of the present invention. FIG. 34 shows the plan view of FIG. 33 with a grid overlay showing that a horizontal wellbore 1000 m in length, with fractures extending 200 m both above and below the wellbore, will catch hydrocarbons or gas from a reservoir area of approximately 40,000 m 2 .
FIG. 35 shows that vertical or deviated wellbores 38 can be created from a horizontal wellbore 2 in accordance with the methods of the present invention in order to create a further dendritic fracture pattern in the subterranean formation. Such a wellbore and fracture pattern can be used to increase the production of hydrocarbons or gas 30 from a well site, as shown in FIG. 36 . In particular, by having, for instance, a dual wellbore configuration, as shown in FIG. 37 that is 1000 m in length, with each such wellbore having fractures that extend 200 m both above and below each wellbore, the reservoir drainage area increases significantly to approximately 80,000 m 2 (see FIG. 38 ). FIG. 39 shows how each fracture in a dual wellbore contributes to the overall production of the well. | A method of drilling and stimulating subterranean formations is provided that allows a well operator to determine in real time if a fracture treatment has been successful, and whether the fracture treatment composition is sufficient for subsequent fracking. The method involves placing fracture treatments into a wellbore while the drilling operation is still under way. The fracture treatment is bounded in the open hole on one side by the current end of the hole and on the other side by a temporary pack off isolation fluid that has been introduced to the well by way of pumping down the existing drill string or by pumping down a separate frac string. The objective is to place the frac in the reservoir and flow it back very quickly after placement, thus increasing the chances of flowing back harmful formation damaging materials and increasing the relative productivity of the newly placed fracture treatment. | 4 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT
[0001] The U.S. Government may have certain rights in this invention pursuant to the National Institute of Standards and Technology Contract Number 70ANB0H3035 awarded by NIST.
BACKGROUND OF THE INVENTION
[0002] This invention relates to the transmission, reception, detection, synchronization, and use of ultra-wideband communication systems. In particular, it pertains to a continuous noise transmitted-reference, delayed hopped (TR/DH) ultrawideband radio communications system.
[0003] Conventional ultra-wideband (UWB) radio systems operate by transmitting and receiving a sequence of very short radio frequency (RF) pulses, the duration of which is typically less than a nanosecond. This is referred to as impulse radio. The individual pulses typically have low energy. Consequently, the low duty cycle of the pulsed waveform results in a very low average power.
[0004] One conventional approach to implementing UWB communications systems is to utilize a pulse position modulation (PPM) scheme to impress information onto a UWB carrier. PPM is an orthogonal signaling scheme by which a receiver determines in which one of a number of different time windows a received pulse appears, and this determination conveys a quantum of information, e.g., if there are two possible time windows, determination of one window conveys one bit of information; for three windows, a trit of information is conveyed, for four windows, two bits, and so on.
[0005] Successful operation of a PPM system requires accurate time synchronization be acquired and maintained between transmitter and receiver. For example, for an UWB PPM system, this synchronization must be accurate to within a fraction of the pulse duration. Because the pulse duration is quite small in a UWB system, the synchronization requirements are quite stringent. The time required to establish synchronization for this method can be prohibitive, and acquisition is not always possible in the presence of multiple access interference, which occurs when more than one pair of transmitters and receivers is active at the same time. A long acquisition time is a major risk in the use of conventional UWB impulse radio communications. Therefore, a need exists for UWB communication systems without the synchronization difficulties associated with conventional approaches.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention consists of the combination of two chief features and innovations surrounding each of them. The first of these is known in the art as transmitted-reference (TR). The TR technique is defined as the transmission of two versions of a wideband carrier, one modulated by data and the other unmodulated. These two signals are recovered by the receiver and are correlated with one another to perform detection of the modulating data. The commonly used wideband carrier is a continuous, wideband pseudo-noise source, and the modulated and unmodulated versions are typically separated from one another in either time or frequency. In the present invention, the carriers used are continuous, wideband noise or continuous, wideband pseudo-noise. Thus, in the present invention, the term “transmitted-reference” refers to the transmission and reception of multiple instances of a noise or pseudo-noise waveform that are separated from each other by specific time intervals, known to the receiver. The noise waveform by itself is referred to as the carrier. Information is carried by such a signal by modulating the relative phase of the two transmitted noise waveforms. The receiver correlates the received signal with a delayed version of itself over a finite interval to demodulate the signal. In contrast to impulse radio methods, the use of the transmitted-reference technique makes synchronization with the individual pulses unnecessary. On the other hand, it also imposes a signal-to-noise ratio (SNR) penalty when compared with impulse radio techniques.
[0007] When two UWB TR signals are generated with different delays, it is possible, under certain conditions, to receive and demodulate both of them simultaneously, by applying two separate correlators to the same received signal. Thus, the use of different delays, each associated with a separate transmitter, imparts a certain amount of multiple access capacity to an UWB TR communications system. In one embodiment, “capacity” is defined as the supportable number of simultaneous users of the communications system.
[0008] The second feature of the present invention is a type of multiple access scheme called “delay hopping”. In the context of UWB communications, delay-hopping refers to the method of varying the delay used in the TR UWB transmission in a fixed pattern known both to the transmitter and to the receiver. This pattern constitutes a code word, and multiple access capacity is obtained through the code-division multiple access (CDMA) technique.
[0009] CDMA is a multiple access method that allows users to access the channel in a random manner. Signal transmissions from different users can completely overlap in both time and frequency in a CDMA system. The demodulation of these signals makes use of the fact that each signal is associated with a code sequence known to the receiver, and this code is usually referred to as a spreading code. Spreading codes of different transmitters should be orthogonal (or nearly so) in the sense that multiple codes can be detected simultaneously with little interference to one another.
[0010] One representative embodiment of the present invention consists of combining the TR and DH techniques to create a UWB communications scheme for transmitting a continuous noise transmitted reference that is easy to synchronize and has a usable level of multiple access capacity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a block diagram of one representative embodiment of a transmitter for transmitting a continuous noise, delay hopped, transmitted reference.
[0012] [0012]FIG. 2 is a block diagram of another representative embodiment of a transmitter for transmitting a continuous noise, delay hopped, transmitted reference.
[0013] [0013]FIG. 3 is a block diagram of one representative embodiment of a receiver.
[0014] [0014]FIG. 4 is a block diagram of one representative embodiment of a bank of correlators.
[0015] [0015]FIG. 5 is a block diagram of one representative embodiment of a CDMA code word correlator.
[0016] [0016]FIG. 6 is a block diagram of another representative embodiment of a receiver.
[0017] [0017]FIG. 7 is a diagram of the power spectral density of a noise carrier.
[0018] [0018]FIG. 8 is a diagram of the power spectral density of transmitted reference delay hopped modulated noise carrier.
[0019] [0019]FIG. 9 is a diagram of a modulated signal.
[0020] [0020]FIG. 10 is a diagram of the outputs of the correlator multipliers of one representative embodiment of the receiver.
[0021] [0021]FIG. 11 is a diagram of the output of the integrator of one representative embodiment of the receiver.
[0022] [0022]FIG. 12 is a diagram of an output of the CDMA code word correlator.
DETAILED DESCRIPTION OF THE INVENTION
[0023] In one embodiment, the specific transmitted-reference (TR) method described here requires the transmission of at least two continuous noise waveforms. The two continuous noise waveforms are separated by a time interval, D, known to both the receiver 300 (FIG. 3) and transmitter 100 (FIG. 1). The transmitted data is encoded by the relative amplitude polarity of the two continuous noise waveforms. One of the transmitted waveforms is always transmitted with the same polarity; this waveform is the reference signal and the other waveform, whose polarity is modulated, is the information-bearing signal. The name “transmitted-reference” comes from the fact that the reference signal is transmitted along with the information-bearing signal.
[0024] As shown in FIG. 1, one embodiment of a transmitter 100 used to transmit the continuous noise transmitted reference comprises a wideband noise source 110 connected to a delay 160 of delay time interval (D) and a summer 170 . The output of the delay 160 is connected to information modulator 130 that is also connected to the summer 170 . An antenna 180 is connected to the summer 170 . In this embodiment, two instances of the continuous noise waveform are separated by delay time interval (D). The delay time interval (D) is known by the transmitter 100 and the receiver 300 (FIG. 3). The transmitted data is encoded by the relative amplitude polarity of the continuous noise waveforms.
[0025] In another embodiment of the transmitter 100 , as shown in FIG. 2, a wideband noise source 110 is connected to a spectral shaping device 120 to produce a continuous noise carrier. The wideband noise source can comprise a back biased diode and passing the output of the diode through a capacitor to remove any DC bias. Also, the wideband noise source can comprise a high speed pseudo random noise generator. The spectral shaping device 120 filters the output of the wideband noise source 110 . In one embodiment, the spectral shaping device 120 can comprise an analog filter. In another embodiment, the spectral shaping device 120 can comprise a digital filter. The spectral shaping device 120 removes energy from predetermined frequency bands to protect the integrity of the communication and/or to comply with federal government regulations. The spectrally shaped continuous noise transmitted reference is provided to the summer 170 and information modulator 130 .
[0026] In one embodiment, the information modulator 130 impresses a delay hop code division multiple access (CDMA) code word on the continuous noise carrier from the spectral shaping device 120 . A delay hop controller 140 also connected to the multiplexer and data polarity switch 150 derives delay hop CDMA code word 135 . Information symbols 145 are provided to the delay hop controller 140 that uses the information symbols 145 to generate the delay hop CDMA code word 135 . This code word consists of a sequence of delay values and an associated sequence of chip polarities of phases. The delay hop controller 140 , in one embodiment, comprises a finite state sequential machine. In one embodiment, the code word comprises N C chips. Each of the N C chips comprises a pair of continuous noise waveforms separated by a fixed time interval or delay.
[0027] The multiplexer and data polarity switch 150 controls the application and routing of the wideband continuous noise waveforms to a band of fixed delays 160 and the application of the chip polarity values to the information-bearing waveform. In one embodiment, the delays 160 can comprise discrete delay analog components, such as, sections of coaxial transmission cable. In another embodiment, the delays 160 can comprise digital delay components. In another embodiment, where the noise source 110 comprises a pseudo random noise source, the delays 160 can be created by the pseudo random noise source when the noise is generated. The multiplexer switch 150 is controlled by the delay hop controller 140 by generating the delay hop CDMA code words 135 according to predetermined design criteria as imposed by bounds on the cross-correlations of the delay hop CDMA code words 135 . The output of the spectral shaping device 120 and the outputs of the fixed delays 160 are combined by a summer 170 and summed to produce a continuous noise transmitted reference signal that comprises a sum of two instances of the continuous noise carrier generated by the wideband noise source 110 wherein a first instance comprises an undelayed continuous noise waveform and the second instance comprises the delayed instance of the at least one of the continuous noise waveforms impressed with the modulated delay hop CDMA code word 135 . The continuous noise waveform is provided to filter 175 for further filtering and then is supplied to the antenna 180 and radiated.
[0028] Delay hopping is a code division multiple access (CDMA) scheme to be used with transmitted reference UWB. A limited amount of multiple access capacity is available in TR UWB by transmitting and receiving continuous noise transmitted reference signals with separate delays. A receiver 100 tuned to one delay will respond to received continuous noise transmitted reference signal at a separate delay at a far lower energy level than it would to continuous noise transmitted reference signals transmitted with its own delay value. However, when multiple transmissions with different delays are present at the receiver's antenna 310 , spurious correlations between continuous noise transmitted reference signal originating from different transmitters can occur. By using CDMA code words whose chips represent a multiplicity of delays and a multiplicity of relative signal polarities between the reference and the information-bearing signal, delay hopping allows for a greater multiple access capacity than simply transmitting with different delays.
[0029] A transmitted reference/delay hopped (TR/DH) code word (also termed delay hop CDMA code word 135 ) consists of N C chips, transmitted sequentially. Each of the N C chips comprising a continuous noise transmitted reference separated by a fixed time interval. The continuous noise transmitted reference in different chip intervals are, in general, characterized by different delays. Note that the chip values are distinct both in associated delay value and in the polarity of the transmitted chip. When a code word of N C chips is used to send one data bit, then if the data bit to be sent is a one, all information-bearing signals in each chip of the code word have the polarity of the code word polarity bit. If the data bit to be sent is zero, then all information-bearing signals in each chip of the code word are transmitted with the opposite polarity of the code word polarity bit.
[0030] Typical values of the parameters are as follows. The number of chips in a code word (N c ) will be in the range of 50 to 1000, and the duration of each chip will be in the range of 1 to 10 microseconds. The time delays separating the two continuous noise transmitted reference signals is drawn from a small set of possible time intervals. While there is no fundamental limitation on the duration of the intervals separating the continuous noise transmitted reference signals, shorter delays will be more accurately implementable in the transmitter 100 and the receiver 300 .
[0031] The DH CDMA code words 135 are the most important part of the delay-hopped code division multiple access (CDMA) scheme. The DH CDMA code words 135 can easily be found using a computer search. For example, we have generated a set of 1000 of them, each composed of 200 chips, with delays drawn from a set of 16 possible delays. All of these DH CDMA code words 135 have autocorrelation side lobes that are less than 7% of the peak autocorrelation in absolute value. The maximum of the absolute value of the cross-correlation at any lag between any pair of these words is less than 10% of the peak autocorrelation. Longer codes, composed of more chips, will have even better correlation properties.
[0032] The top-level structure of the receiver 300 is depicted in FIG. 3. The receiver 300 for a transmitted reference/delay hopped (TR/DH) code word consists of a bank of correlators 320 connected to antenna 310 . Each correlation in the bank of pulse-pair correlators 320 is tuned to a different delay. The bank of correlators 320 is connected to a CDMA code word correlator 350 having output 350 . The CDMA code word correlator 340 is implemented, in one embodiment, as software running on a digital signal processor (DSP) 134 . In another embodiment, the code word correlator 340 may be a programmable logic device (PLD) or application-specific integrated circuit (ASIC). The outputs of bank of correlators 300 are sampled by A/D converters 330 at a sample rate that is typically from 2 to 10 msps. This rate is determined by the chip time. In general, it is desirable to have two or more samples per chip.
[0033] Each correlator in the bank of correlators 320 , as depicted in FIG. 4 is an analog circuit comprising a delay 322 , a signal multiplier 324 (such as a four-quadrant Gilbert cell) and a finite-time integrator 326 . The signal is split into two paths, of which one is delayed. The two versions of the received signal are multiplied, and the product is integrated over a chip time. The delay 322 is such that the leading pulse in the delayed circuit path is registered in time with the trailing pulse in the undelayed circuit path. This non-zero-mean product is integrated over a chip interval to produce a chip signal. Note that this circuit implements the mathematical operation of estimating the correlation of the received signal at a lag given by D.
[0034] The CDMA code correlator 340 will take samples of the multiple outputs of the bank of pulse pair correlators 320 and add them together in a manner dictated by the expected CDMA code word. The objective of this operation is to produce the registered sum of all the chip signals. When the expected code word matches the transmitted code word 135 , this operation will have the effect of applying a gating waveform, matched to the entire delay hopped (DH) code word waveform, to the observed data at the output of the correlators 320 . If the gating waveform matches the shape of the chip signal waveform, a matched filter is implemented; however, this requires knowledge of the relative timing of the sample clock and the transmitter chip clock. If the gating waveform applied to the individual chip is rectangular, with duration 2T c , then the effect of the CDMA code word correlator 340 is to add all of the individual chip waveforms in phase, producing an output which is a high-SNR version of the individual chip waveform.
[0035] In one embodiment, the structure of the CDMA code correlator is depicted in FIG. 5. The specific code correlator 340 depicted uses a CDMA code word 135 that matches the correlator bank 320 output depicted in FIG. 4. Note that the chip time delays (D chip time ) 342 and signs (additions and subtractions) cause the elementary correlator peaks to be aligned in time with the same signs. The delayed outputs of the A/D converters from the CDMA code word correlator are summed by summer 344 and provided as output 350 . Since the sample period of the A/D converters 330 has been specified to be a fraction of the chip period, the delays 342 in FIG. 5 may, in one embodiment, all be implemented as a number of digital storage devices, with provision for passing stored data from one to the next. Thus, in one embodiment, the CDMA code word correlator 340 of FIG. 5 depicts a synchronous digital circuit such as would be implemented in a programmable logic device (PLD) or ASIC.
[0036] In FIG. 6, one embodiment of the transmitter 300 uses baseband demodulation to modify the shape of the correlation function of the received signal. Antenna 201 receives the ultra-wideband signal which is then bandpass filtered and amplified by amplifier 202 . This signal is mixed in quadrature in mixers 203 a and 203 b resulting in real and imaginary parts of the complex incoming signal. The frequency of the local oscillator is chosen to approximate the frequency of the maximum spectral power density of the received signal from amplifier 202 . The baseband signals from mixers 203 a and 203 b are filtered by low pass filters 610 and are delayed by time D in delays 21 a and 21 b , respectively. The outputs of delays 21 a and 21 b are then correlated with the undelayed signals from mixers 203 a and 203 b using analog multiplying correlators 22 a , 22 b , 22 c , and 22 d . The analog outputs from these correlators are subtracted and added in subtractor 220 and adder 221 , respectively. The resulting analog signals from subtractor 220 and adder 221 can be seen to be an analog implementation of a complex correlation between the delayed and undelayed versions of the complex baseband signal from mixers 203 a and 203 b . The difference output of subtractor 220 is the real part, and the summed output of the adder 221 is the imaginary part of the complex correlated signal. Integrators 23 a and 23 b perform a complex integration which is digitized by ADCs 210 a and 210 b . The digitized results are sent to DSP 215 . When implementing a receiver with multiple delay channels, then the items in the dotted line ( 21 a - b , 22 a - d , 23 a - b , 210 a - b , 220 , 221 ) are repeated once for each different delay channel. Each receiver requires only one copy of antenna 201 , amplifier 202 , mixers 203 a and 203 b , local oscillator 204 , phase shifter 205 and DSP 215 .
[0037] The receiver 300 of FIG. 6 calculates the phase angle and amplitude of the complex value formed by the values from ADCs 210 a and 210 b . The operation of estimating the phase angle of a sequence of complex values modulated by an information sequence can be performed either through the use of local bit decisions or by squaring the input data. The correction of the phase allows the complex output of ADCs 210 a and 210 b to be converted to a real number the sign of which depends on the phase angle calculated from ADCs 210 a and 210 b . The real data so produced is either positive or negative, depending upon the relative phases of the pulses in the received pulse pairs, and so can be used in a manner which is completely analogous to the output of the receiver 100 depicted in FIG. 4. The absolute value of this data is determined by the modulus of the correlation function at this mismatched delay, and so it is relatively insensitive to delay mismatch.
[0038] Note that if multiple delay channels are required are required in the receiver of FIG. 6, the same I/Q converter can be shared by all the delay channels. Note also that if additional protection against delay variations is required, multiple delays per receiver channel can be implemented. For example, each delay channel could be replicated three times, once with the nominal delay, once with the nominal delay minus an offset and once with the nominal delay plus the same offset. For each transmitter being tracked, the best delays for each channel could be found by comparison of output energies.
[0039] Since the receiver 300 of FIG. 6 is operated by computing the autocorrelation of the input signal at a certain lag, the receiver 300 will also compute the autocorrelation at the same lag of any noise that is added to the signal. If the noise autocorrelation at that lag is non-zero, then it will produce an additive offset to the signal autocorrelation that will increase the bit error probability. This effect can be corrected in one of two ways, both of which require knowledge of the noise autocorrelation function. The first option is to specify the nominal delays at known zeros of the noise autocorrelation. The second is to subtract the known, non-zero noise correlation value from the output of the receiver prior to detection of bits. The noise autocorrelation function can be obtained from the frequency response functions of the front end filters that band limit the noise.
[0040] As an example, consider the power spectral densities plotted in FIG. 7. This example will use a noise carrier. FIG. 7 shows the power spectral density (PSD) of a noise carrier with a 2 gigahertz bandwidth and a center frequency of 2 gigahertz. This is the sample spectrum of a simulated carrier, formed by filtering uncorrelated noise sampled at 40 gigahertz with a 551-tap FIR filter, with the desired bandpass response. FIG. 8 shows the same carrier modulated by a TR/DH CDMA code word 135 . In one embodiment, the CDMA code word 135 is composed of sixteen 600-nanosecond chips, each imposing correlation on the noise carrier at one of four lags: 1.65 nanoseconds, 2.65 nanoseconds, 3.65 nanoseconds and 4.65 nanoseconds. As shown in FIG. 8, the most noticeable effect of the TR/DH modulation is to raise the overall sidelobe level. It should be appreciated that the raised overall sidelobe levels shown in FIG. 8 can be filtered out using filter 175 (FIG. 1).
[0041] FIGS. 9 - 12 depict the various stages in the demodulation of the noise signal that has a spectrum depicted in FIG. 8. FIG. 9 is a portion of the noisy signaling waveform, and the segment depicted has a duration of 25 nanoseconds. FIG. 10 depicts the outputs of the four multipliers in the bank of correlators 320 . Each correlator in the bank of correlators 320 has, for example, the structure depicted in FIG. 4. FIG. 10 depicts a time interval of 15 microseconds, during which the transmission of a single TR/DH code word of duration 9.6 microseconds takes place. The four pulse-pair correlators are tuned to the four delays used in the modulation: 1.65 nanoseconds, 2.65 nanoseconds, 3.65 nanoseconds and 4.65 nanoseconds. Note that the mean levels of the outputs of the multipliers shift away from zero at certain times; these times correspond to the times of the transmitted chips. FIG. 11 depicts the outputs of the four integrators of the pulse-pair correlators. The waveforms are the actual chip waveforms arising from the simulation. The DH CDMA code 135 transmitted in this example can be expressed as an ordered sequence of integers {3, 4, 1, −4, −1, −2, 3, −2, 4, −1, −3, −2, −4, 1, 3, −4}. This sequence of numbers represents the numbers of the transmitted delays, numbered from shortest to longest, and the signs of the numbers denote the polarity of the transmitted chip. The CDMA code word 135 can be “read off” the waveforms depicted in FIG. 11. For example, reading from left to right, the first channel to produce an output waveform is channel 3 , and the polarity of that waveform is positive. FIG. 12 shows the output of a DH CDMA code correlator 340 of the type depicted in FIG. 3 when the input consists of the chip waveforms depicted in FIG. 11. For this relatively short code, the code correlator output has high sidelobes. Other DH CDMA codes will have upwards of a thousand chips, and a much lower ratio of peak absolute sidelobe level to peak mainlobe level in the output correlation.
[0042] The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings and with the skill and knowledge of the relevant art are within the scope of the present invention. The embodiment described herein above is further intended to explain the best mode presently known of practicing the invention and to enable others skilled in the art to utilize the invention as such, or in other embodiments, and with the various modifications required by their particular application or uses of the invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art. | An ultra-wideband (UWB) communications system combines the techniques of a transmitted reference (TR) and a multiple access scheme called delay hopping (DH). Combining these two techniques using UWB signaling using a continuous noise transmitted waveform avoids the synchronization difficulties associated with conventional approaches. This TR technique is combined with the DH multiple access technique to create a UWB communications scheme that has a greater multiple access capacity than does the UWB TR technique by itself. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62/110,482, filed Jan. 31, 2015, which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to cleaning devices, and more particularly to robotic cleaning devices.
BACKGROUND OF THE INVENTION
[0003] Over the years, various robotic devices have been devised to clean or vacuum floors and other surfaces. The use of a mobile robot with a cleaning head is known in the art as a solution to the need for autonomous and automatic floor cleaning devices. The robotic cleaners in the prior art can use a vacuum cleaner head or a sweeping attachment to clean floors as they move.
[0004] While robotic cleaners have gotten smaller over time, even the current robotic cleaners are too large to fit under low horizontal obstructions, such as the area under an entertainment console or sideboard. Open areas in a room can be cleaned using conventional techniques or a robotic cleaner, but neither is capable of easily cleaning under low furniture. Because these areas with low overhead clearance can only be cleaned by moving the obstructing furniture, they often go without cleaning for prolonged periods of time. Therefore, there is a need for a device that is able to automatically identify areas in a room with low overhead clearance and that has the capability to clean those areas.
[0005] While the robotic cleaners in the prior art are capable of vacuuming or sweeping a room with stationary objects, they are unable to adjust to changes in the environment (e.g. a chair moving). Existing robotic cleaners often use an array of sensors coupled with a preset expanding pattern or a creeping line pattern to cover an entire room. These navigation systems are only effective in simple and static environments and are prone to problems in dynamic environments where a previously identified object moves. Other robotic cleaners in the prior art use a random pattern consisting of operating in a straight line until an obstruction is detected. This programming can cause the robot to be stuck in a corner or within a small area with multiple obstructions, such as under a table and chairs. Therefore, there is a need for a robotic cleaner with a navigation system capable of adapting to a dynamic environment.
[0006] The robotic cleaners in the prior art are also prone to getting stuck in corners or falling off raised areas, such as off a stair. A solution in the prior art includes the use of complex electronic boundaries set into the navigation programming, but this only provides parameters for operation without providing an algorithm for determining when the robot is in danger of becoming stuck. Other solutions in the prior art use reactive systems to detect when the robot is stuck to merely turn the device off. The cleaning robots in the prior art are unable to determine when they are in danger of becoming stuck and initiating an action to avoid the situation. When stuck, the cleaning robots in the prior art are also inefficient at freeing themselves due to their large size and weight. Therefore, there is a need for a robotic cleaner that is capable of detecting when it is at risk of becoming stuck so that it can initiate a movement to avoid the condition. There is also a need for a robotic cleaner capable of efficiently freeing itself in the event it does become stuck on an obstruction.
[0007] Existing robotic floor sweepers use a rectangular cleaning pad located in front of the robot. The rectangular pusher pads are unable to clean in corners or small gaps and tend to push dirt into the corners of a room rather than collecting it. The pusher style of cleaning pad is prone to becoming stuck on small irregularities in the floor surface and requires a relatively heavy robot to provide adequate traction to push the cleaning pad. Therefore, there is a need for a robotic cleaner with a cleaning pad that is capable of cleaning corners and capable of moving over small irregularities on the surface of a floor.
[0008] Accordingly, it is an object of the present invention to provide a robotic cleaner capable of fitting under areas with low overhead clearance and targeting those areas for cleaning. It is also an object of the present invention to provide a robotic cleaner that is capable of adapting to a dynamic environment and detecting when it is in danger of becoming stuck to avoid the condition. It is also an object of the present invention to provide a lightweight mobile robot and cleaning pad attachment capable of cleaning in corners and under low furniture.
BRIEF SUMMARY OF THE INVENTION
[0009] The present invention is a robotic floor cleaning apparatus comprising a mobile robot with a detachable cleaning element extending from the bottom of the mobile robot. The mobile robot comprises a case containing a micro-controller, a power supply, two or more wheels and associated drive motors, upward facing ultrasonic sensors, collision detection sensors and downward facing infrared transmitters and receivers. The present invention can use multiple types of detachable cleaning elements, including disposable and reusable versions.
[0010] The present invention uses a navigation system that in one mode, uses the data collected from the upward facing ultrasonic sensors to target areas in a room with a low overhead clearance for cleaning. The navigation system is also capable of detecting patterns in the mobile robot's movements that are precursors or indicative of the mobile robot being stuck and uses a variety of preprogrammed motions to avoid the situation. The navigation system specifically uses an algorithm that randomizes the movements of the apparatus and reacts to the environment to provide more thorough floor coverage than possible using the navigation systems in the prior art.
[0011] While the invention described has been described as being particularly applicable to robotic cleaners, it is appreciated that the present invention could be used in other applications within the scope of the inventive concept.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of the robotic floor cleaning apparatus with a first embodiment of a disposable cleaning element attached.
[0013] FIG. 2 is a perspective view of the robotic floor cleaning apparatus with the top cover removed and with a first embodiment of a disposable cleaning element attached.
[0014] FIG. 3 is a top view of the robotic floor cleaning apparatus with the top cover removed and with a first embodiment of a disposable cleaning element attached.
[0015] FIG. 4 is a bottom view of the robotic floor cleaning apparatus with the bottom cover removed.
[0016] FIG. 5 is a front view of the robotic floor cleaning apparatus with a first embodiment of a disposable cleaning element attached.
[0017] FIG. 6 is a side view of the robotic floor cleaning apparatus with the top cover removed and with a first embodiment of a disposable cleaning element attached.
[0018] FIG. 7 is a bottom view of the robotic floor cleaning apparatus without a cleaning element attached.
[0019] FIG. 8 is a bottom view of the robotic floor cleaning apparatus with a first embodiment of a disposable cleaning element attached.
[0020] FIG. 9 is a perspective view of a first embodiment of a disposable cleaning element.
[0021] FIG. 10 is a perspective view of a first embodiment of a reusable cleaning element.
[0022] FIG. 11 is a perspective view of a second embodiment of a disposable cleaning element.
[0023] FIG. 12 is a perspective view of a second embodiment of a reusable cleaning element.
[0024] FIG. 13 is a block diagram of the apparatus.
[0025] FIG. 14 is a flow chart showing the operations carried out by the apparatus.
[0026] FIG. 15 is a flow chart showing the operations carried out by the apparatus when in the clean step.
[0027] FIG. 16 is a flow chart showing the operations carried out by the apparatus when in the backup and spin step.
[0028] FIG. 17 is a flow chart showing the operations carried out by the apparatus when in the move forward step.
[0029] FIG. 18 is a flow chart showing the operations carried out by the apparatus when in the forward under step.
[0030] FIG. 19 is a flow chart showing the operations carried out by the apparatus when in the spiral outward step.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIG. 1 shows the apparatus of the present invention 10 in an exemplary configuration as a robotic floor sweeper. The apparatus 10 comprises a mobile robot 11 with a first embodiment of a detachable disposable cleaning element 12 attached to the underside of the mobile robot and in contact with the surface to be cleaned. The mobile robot 11 includes an upper case 13 and a lower case 14 that provide the main body of the mobile robot and support for the internal components. Providing propulsion are a left wheel 15 and a right wheel 16 driven by electric motors not seen in this view.
[0032] The mobile robot 11 includes a variety of sensors connected to an internally mounted micro-controller 33 (visible in FIG. 2 ). Visible through openings 20 and 21 in the upper case 13 are upward facing ultrasonic sensors 22 . The ultrasonic sensors 22 are used to detect the height of surfaces above the mobile robot 11 . At the front of the mobile robot 11 is a bumper 24 capable of displacing switches on internally mounted collision sensors (not shown in this view).
[0033] Also visible through openings in the upper case 13 are a power switch 23 , a trouble light 26 and a status light 27 . The trouble light 26 illuminates when certain problems are detected by the mobile robot 11 . The status light 27 is green in normal operation and changes in its lighting configuration can be used to indicate different modes of the apparatus 10 . In the preferred embodiment, the trouble light 26 and status light 27 are LED lights, but it is appreciated that multiple types of lights are available in the art and capable of being used in this application.
[0034] FIG. 2 contains a perspective view of the apparatus 10 with a first embodiment of a disposable cleaning element 12 attached and the top cover 13 removed (not shown in this view). The top cover 13 and the bottom cover 14 contain multiple internally molded partitions and extrusions to sandwich and securely hold the internal components when the top cover 13 and bottom cover 14 are fastened together. The top cover 13 and bottom cover 14 can be fastened using mechanical fasteners or an adhesive. In FIG. 2 , the top cover 13 has been removed, leaving the internal components sitting on the bottom cover 14 .
[0035] The power supply 30 comprises a battery or other electrical storage device. The preferred embodiment uses a NiMH (Nickel metal hydride) battery, but it is appreciated that multiple types of electrical storage devices would be appropriate for this application. Electrically connected to the battery 30 is a connector 31 , also connected to the power printed circuit board (“PCB”) 32 .
[0036] The power PCB 32 contains a micro-controller 33 , a power board 34 , a motor driver 35 and a charging port 36 . The power button 23 , trouble light 26 and status light 27 are also mounted to the power PCB 32 . The specific functions and the interrelationship of these components is discussed in further detail in the block diagram of FIG. 13 and its associated description in the specification.
[0037] Mounted towards the front of the apparatus 10 are the ultrasonic sensors 22 and collision sensors 38 . The ultrasonic sensors 22 are electrically connected to and mounted above a sensor PCB 37 which is not visible in this view (the sensor PCB 37 is visible in FIG. 3 ). The collision sensors 38 are fixed to the sensor PCB 37 and detect when the bumper 24 is displaced towards the collision sensors 38 .
[0038] The left electric drive motor 40 and right electric drive motor 41 are mounted on movable arms 42 and coupled to their respective drive wheels 15 and 16 through a reduction gear assembly. The movable arms 42 are mounted to suspension cage 43 at pivots 44 , allowing the movable arms to rotate in a limited range about an axis substantially parallel to the longitudinal axis of the mobile robot 11 . Between the movable arms 42 and the suspension cage 43 are springs 45 which push the movable arms 42 downward. When at rest, the movable arms 42 are at their lower rotational limit and deflect upwards when in motion, in reaction to surface irregularities.
[0039] FIG. 3 contains a top view of the apparatus 10 with a first embodiment of a disposable cleaning element 12 attached and the top cover 13 removed (not shown in this view). Similar to FIG. 2 , the internal components are resting on the bottom cover 14 in this view. Visible in this view is the selector switch 50 mounted to the underside of the power PCB 32 . The selector switch extends through opening 51 between the upper case 13 (not shown in this view) and lower case 14 . In the preferred embodiment, the selector switch 50 is used to cycle the apparatus 10 between various cleaning modes.
[0040] Also visible in FIG. 3 is the sensor PCB 37 , which is electrically connected to the power PCB 32 . In the preferred embodiment, the sensor PCB 37 is connected to the power PCB 32 using a six cable connector. Below the sensor PCB 37 are the infrared transmitters 52 , used as fall detectors. The infrared transmitters 52 are downward facing and detect the presence of the ground beneath the apparatus 10 . When the infrared transmitters stop detecting the ground under the apparatus 10 , the micro-controller interprets this change as a fall or impending fall depending on the duration of the signal. The infrared transmitters 52 are mounted to the bottom case 14 using brackets 55 .
[0041] FIG. 4 contains a bottom view of the apparatus 10 with the bottom cover 14 removed (not shown in this view). In this view the internal components are resting on the top cover 13 as they would be if the apparatus 10 was inverted. In this bottom view, the underside of the power PCB 32 and the sensor PCB 37 are visible. On the underside of the power PCB 32 is selector switch 50 . On the underside of the sensor PCB 37 is a path illuminating light 56 . The path illuminating light 56 is used to illuminate the front of the apparatus 10 and make it more visible to people in the area. There is an opening between the upper case 13 and lower case 14 containing a clear plastic lens 57 to allow the light from the path illuminating light 56 to travel through the case.
[0042] Also visible in FIG. 4 are the infrared transmitters 52 and their associated brackets 55 . The brackets 55 are normally fixed to the bottom case 14 , however, as this is a bottom view, the infrared transmitters 52 and brackets 55 are merely placed in the upper case 13 to show their arrangement. Also in this view are the clear lenses 53 mounted to the bottom case 14 using a skirt 54 that snaps into an opening on the bottom case 14 to hold the assembly.
[0043] In FIGS. 5 and 6 are views of the apparatus 10 with a first embodiment of a detachable disposable cleaning element 12 attached to the underside of the mobile robot 11 . In FIG. 5 is a front view of the apparatus 10 and in FIG. 6 is a side view of the apparatus 10 with the top cover 13 (not shown in this view) removed. The bumper 24 contains a logo 25 cut through the bumper material to allow the light from the path illuminating light 56 to travel through the bumper. In the preferred embodiment, the bumper 24 comprises a rigid plastic base with a rubber or rubberized coating to reduce the amount of sound created when the bumper impacts an obstruction during use. The bumper 24 can alternatively be made entirely of a semi-rigid material to reduce noise or a transparent or semi-transparent material to allow light to pass through without the use of a logo 25 cut through the bumper.
[0044] In FIG. 7 is a bottom view of the apparatus 10 without a cleaning pad installed. On the underside of the mobile robot 11 are openings 25 that allow the internally mounted infrared sensors to view the ground ahead of the wheels 15 and 16 . Visible in this view are the four screws 71 that secure the lower case 14 to the upper case 13 (not shown in this view). While the preferred embodiment uses screws, other types of mechanical fasteners or an adhesive could be substituted. On the surface of lower case 14 are three recesses 72 , each containing a hook and loop fastener 73 . The recesses 72 are recessed into the surface of lower case 14 to the depth necessary to make the surface of hook and loop fasteners 73 flush with the surface of the lower case 14 . The hook and loop fasteners 73 can be either of the hook or loop variety as long as the type used on a corresponding attachment is of the opposite type. The hook and loop fasteners 73 are secured to the lower case 14 with an adhesive in the preferred embodiment, but it is appreciated that there are other methods in the art to achieve this end.
[0045] FIG. 8 is a bottom view of the apparatus 10 with a first embodiment of a disposable cleaning element 12 attached to the underside of the mobile robot 11 . In the preferred embodiment, the disposable cleaning element 12 is made largely of an electrostatic cleaning cloth 64 , however it is appreciated that there are other materials known in the art that can be used as a substitute. The disposable cleaning element 12 has a solid area of electrostatic cleaning cloth 64 in the areas located directly under the bottom case 14 . The disposable cleaning element 12 follows the contours of the bottom case 14 and avoids fouling the wheels 15 and 16 or covering the clear lenses 53 . On the part of the disposable cleaning element 12 that extends away from the bottom case 14 , there are a multitude of slits 60 in the electrostatic cleaning cloth 64 to allow the cleaning element to remain flexible as the mobile robot moves. The shape of the disposable cleaning element 12 and the slits 60 are designed to minimize the possibility of the cleaning element from becoming caught in the wheels 15 and 16 . Even when sections of the cleaning element 12 are folded towards the wheels, they are unable to reach the wheels.
[0046] The circular shape of the cleaning element 12 combined with the slits 60 complement the navigation programming used in the apparatus 10 and maximize the ability of the apparatus 10 to clean in small corners. When the apparatus turns in corners, the slits 60 allow the material to brush into the corner where a solid cleaning element would bunch up or lift from the surface. The circular shape is also important to the function of the cleaning element 12 and provides a more consistent brushing effect on corners than a rectangular or triangular cleaning element. When the apparatus 10 rotates the circular portion of the cleaning element 12 near a corner, the corner is brushed by each finger of the cleaning material (defined by the slits 60 ) with an approximately equal amount of force. When a cleaning element with a triangular or rectangular shape extending from the bottom case 14 was tested, the rotation of the apparatus 10 caused the material to bunch up and the cleaning effect of each finger was different, creating an inconsistent cleaning action.
[0047] In FIG. 9 is a perspective view of the upper side of a first embodiment of a disposable cleaning element 12 . The area of the cleaning element 12 that presses against the bottom case 14 contains a thin layer of plastic 61 for additional support. The plastic 61 prevents the cleaning element 12 from folding away from the bottom case 14 when in motion. In the preferred embodiment, the plastic 61 is an approximately three mil flexible film and the weight of the mobile robot 11 provides the additional force needed to hold the cleaning element 12 in place. To keep the cleaning element 12 from sliding away from the mobile robot 11 , there is an adhesive strip 62 attached to the top of the cleaning element 12 . In the preferred embodiment, the adhesive strip 62 is double-sided tape, but it is appreciated that multiple types of removable fasteners or adhesives could be used with similar results.
[0048] In FIG. 10 is a perspective view of a first embodiment of a reusable cleaning element 112 , which can be used as a substitute for cleaning element 12 . In this embodiment, the reusable cleaning element 112 is made largely of microfiber cloth 164 , however it is appreciated that there are other materials known in the art that can be used as a substitute. The microfiber cloth 164 covers the entire bottom surface of the reusable cleaning element 112 . The reusable cleaning element 112 has a similar overall shape as the disposable cleaning element 12 , but with detailed differences to optimize its performance. The material used for the reusable cleaning element 112 in this embodiment is softer and more flexible than the material used for the disposable cleaning element 12 . Because the reusable cleaning element 112 uses a softer and more flexible material, it is able to remain on the surface as the mobile robot 11 rotates without as many slits 160 .
[0049] In this alternative embodiment, the reusable cleaning element 112 uses three slits 160 extending away from the bottom case 14 . One slit 160 follows the centerline of the apparatus 10 , extending rearward. The other two slits 160 extend from the rear corners of the bottom case 14 and extend rearward and to the side. These two slits 160 terminate at a point on the cleaning element 112 that is directly behind the cutouts 163 for the drive wheels. This arrangement allows the cleaning element 112 to slide against a wall easily, while still allowing the mobile robot 11 to rotate and use the rotating motion to move the cleaning element 112 through a corner.
[0050] Similar to the disposable cleaning element 12 , the reusable cleaning element 112 uses a thin layer of support material 161 to increase the rigidity of the area which it is applied. The support material 161 can be a fabric or other washable material, including some plastics that are durable enough to be washed. To keep the cleaning element 112 centered on the mobile robot 11 , multiple hook and loop fasteners 162 are used that correspond to the hook and loop fasteners 73 (visible in FIG. 7 ) fixed to the bottom cover 14 .
[0051] In FIG. 11 is a perspective view of a second embodiment of a disposable cleaning element 412 , which can be used as a substitute for cleaning elements 12 and 112 . In this embodiment, the disposable cleaning element 412 is made largely of electrostatic cleaning cloth 464 , however it is appreciated that there are other materials known in the art that can be used as a substitute. The electrostatic cleaning cloth 464 covers the entire bottom surface of the disposable cleaning element 412 .
[0052] In this alternative embodiment, the disposable cleaning element 412 uses five slits 460 extending away from the bottom case 14 . One slit 460 follows the centerline of the apparatus 10 , extending rearward. Two slits 460 extend from the rear corners of the bottom case 14 and extend rearward and to the side. These two slits 460 terminate at a point on the cleaning element 412 that is behind the cutouts 463 for the drive wheels. Two slits 460 extend from the sides of the bottom case 14 and extend rearward and to the side. The disposable cleaning element 412 uses a thin layer of plastic 461 that covers the entire upper surface of the disposable cleaning element 412 to provide additional support. To keep the cleaning element 412 centered on the mobile robot 11 , an adhesive strip 462 is attached to the top of the cleaning element 412 . In the preferred embodiment, the adhesive strip 462 is double-sided tape, but it is appreciated that multiple types of removable fasteners or adhesives could be used with similar results.
[0053] In FIG. 12 is a perspective view of a second embodiment of a reusable cleaning element 512 , which can be used as a substitute for cleaning elements 12 , 112 and 412 . In this embodiment, the reusable cleaning element 512 is made largely of microfiber cloth 564 , however it is appreciated that there are other materials known in the art that can be used as a substitute. The microfiber cloth 564 covers the entire bottom surface of the reusable cleaning element 512 .
[0054] In this alternative embodiment, the reusable cleaning element 512 uses five slits 560 extending away from the bottom case 14 . One slit 560 follows the centerline of the apparatus 10 , extending rearward. Two slits 560 extend from the rear corners of the bottom case 14 and extend rearward and to the side. These two slits 560 terminate at a point on the cleaning element 512 that is behind the cutouts 563 for the drive wheels. Two slits 560 extend from the sides of the bottom case 14 and extend rearward and to the side. The reusable cleaning element 512 uses a thin layer of support material 561 that covers the entire upper surface of the reusable cleaning element 512 to provide additional rigidity to the cleaning element. The support material 561 can be a fabric or other washable material, including some plastics that are durable enough to be washed. To keep the cleaning element 512 centered on the mobile robot 11 , multiple hook and loop fasteners 562 are used that correspond to the hook and loop fasteners 73 (visible in FIG. 7 ) fixed to the bottom cover 14 .
[0055] The second embodiment of a disposable cleaning element 412 and the second embodiment of a reusable cleaning element 512 share multiple advantages over the first embodiment of a disposable cleaning element 12 and the first embodiment of a reusable cleaning element 112 . Cleaning elements 412 and 512 use a support layer 461 and 561 , respectively, that covers the entire top surface of the cleaning element. Cleaning elements 12 and 112 use a support layer 61 and 161 , respectively, that covers only the top surface of the cleaning element that is directly below the mobile robot 11 . Extending the support layer in cleaning elements 412 and 512 to the entire top surface improves contact with the floor when cleaning and reduces production costs because a single cutting die can be used for the cleaning material 464 and 564 and the support layer 461 and 561 . The number of cuts necessary to produce each cleaning element 412 and 512 can be reduced to a single cut by attaching the support layer 461 and 561 to the cleaning material 464 and 564 , respectively, prior to being cut with a cutting die.
[0056] The extension of the support layer 461 and 561 also blocks dirt from collecting on the upper surface of the cleaning elements 412 and 512 , improving their appearance when used for a period of time. In comparison, cleaning elements 12 and 112 tend to collect some dirt on their visible upper surfaces when used.
[0057] Cleaning elements 412 and 512 use the same number and placement of slits 460 and 560 , respectively. Using the same number and placement of slits allows cleaning elements 412 and 512 to be manufactured using a common, or substantially common, cutting die, reducing manufacturing costs. The common pattern also allows both types of cleaning elements to be dispensed from the same dispenser and fit into a substantially similar package.
[0058] In FIG. 13 is a functional block diagram of the major components contained within the apparatus 10 . The block diagram is separated by location, with the components mounted on the power PCB 32 , the components included in the engine compartment 46 , the components mounted on the sensor PCB 37 and the components included in the battery compartment 59 shown in separate groups. The power PCB 32 includes a micro-controller 33 that directs the operations of the cleaning robot. The micro-controller 33 is directly connected to the power board 34 , motor driver 35 , cleaning mode switch 50 , piezo speaker 58 , status light 27 and trouble light 26 . The motor driver 35 is also connected to the left drive motor 40 and the right drive motor 41 . The motor driver 35 can control the speed of the left drive motor 40 and right drive motor 41 independently in forward and reverse. The power board 34 provides power to the components contained in the apparatus from the rechargeable battery 30 . The charging jack 36 completes the circuit between the rechargeable battery 30 and power board 34 when a charging cord is not plugged into the charging jack. When a power cord is plugged into the charging jack 36 to recharge the rechargeable battery 30 , the charging jack breaks the electrical connection with the power board 34 and directs the power to the rechargeable battery. The power switch 23 is connected to the power board 34 and provides a means for a user to turn the apparatus 10 on or off when a power cord is not plugged into the charging jack 36 . In the preferred embodiment, when a power cord is plugged into the charging jack 36 , the power board does not receive power from either the charging jack 36 or the rechargeable battery 30 .
[0059] The components on the sensor PCB 37 are connected directly to and controlled by the micro-controller 33 with the exception of the running lamp 56 . The running lamp 56 is energized when the power board is providing power to the micro-controller 33 from the rechargeable battery 30 . While the components on the sensor PCB 37 are controlled by the micro-controller 33 , they receive power from the power board 34 through an electrical connection not shown in FIG. 13 . Incorporated as part of the sensor PCB 37 are the upward facing object sensors 22 , the collision detectors 38 and the fall detectors 52 . The upward facing ultrasonic sensors 22 are mounted to a controller that is electrically connected to the sensor PCB 37 . In the preferred embodiment, the upward facing sensors 22 are capable of sensing objects up to 20 feet above the sensors, however, in this application, the range of the sensors is limited through the software to approximately two feet. The apparatus 10 targets areas in a room with less than 10-12 inches of overhead clearance for cleaning, making it unnecessary to use the full range of the ultrasonic sensors 22 in this embodiment. While the range of the ultrasonic sensors 22 are being limited by the software in this embodiment, it is appreciated that there may be other applications where it would be preferable to use up to the full range of the ultrasonic sensors 22 . A larger range from the ultrasonic sensors would be necessary if the apparatus 10 was programmed to target areas with between a 10-12 inch and 20 foot overhead clearance or for the apparatus 10 to detect features above, such as a door frame.
[0060] The collision detectors 38 are micro-switches with spring loaded levers. The spring loaded levers push the bumper forward to its resting position and are compressed when the bumper comes in contact with an obstruction. The fall detectors 52 are infrared transmitters and receivers mounted to the bottom of the apparatus 10 . The fall detectors 52 send out a signal and time the response back to determine if the ground is directly under the front of the apparatus 10 . While infrared transmitters and receivers are used in the preferred embodiment, it is appreciated that there are other types of sensors that would be adequate for this function, including ultrasonic sensors.
[0061] The use of infrared sensors as the fall detectors 52 reduces the overall size of and the cost to manufacture the apparatus 10 . A challenge with infrared sensors is that they are sensitive to the color and sheen of the floor surface as well as the amount of ambient light. Certain types of floors with large variations in color, such as a black and white tile floor, generate a large number of false positives on cleaning robots in the prior art. Instead of automatically changing the sensitivity of the infrared sensors, the cleaning robots in the prior art require the user to manually reduce the overall sensitivity of the fall sensors to allow the cleaning robot to travel over surfaces that would otherwise trigger false positives of falling, effectively disabling the fall detection system. To reduce the occurrence of false positives while maintaining the functionality of the fall detectors in all conditions, the preferred embodiment uses the first three seconds of operation to calibrate the infrared sensors. During the first three seconds of the cleaning cycle, the micro-controller 33 records the high values taken from the fall detectors 52 to obtain a range of normal values for the floor type and current lighting conditions. By using the range of values obtained by the infrared sensors in the current cleaning cycle, the apparatus 10 is able to adapt to the current conditions and reduce the chance of false positives that it is falling.
[0062] In FIGS. 14-19 are flow charts showing the operations carried out by the apparatus 10 in the preferred embodiment. Steps in each flow chart that are defined further in a separate figure are denoted by a bold box. The flow charts shown are exemplary in nature and are capable of being changed or modified within the scope of the invention.
[0063] In FIG. 14 is a flow chart showing the functions carried out by the micro-controller 33 during a full cleaning cycle. After the start 200 of the flow chart and before any functions are carried out by the micro-controller 33 , the apparatus goes through a hardware based sequence 201 . The hardware based sequence can occur at any point during the cleaning cycle and does not require explicit checking by the micro-controller 33 to sense a change in the hardware based settings. The first step in the hardware based sequence 201 is to determine whether a charger is connected 202 , specifically, whether a charging cord is plugged into the charging port. When a power cord is plugged in, the apparatus powers down and charges the battery 203 . When a power cord is not plugged in, the apparatus then checks whether the power switch has been pressed 204 . If the power switch has been pressed, the flow chart exits the hardware based sequence 201 and continues to the software based sequence that makes up the majority of a full cleaning cycle.
[0064] With power flowing to the micro-controller, the first software step in the sequence is to play a startup melody, initialize the CPU and sensors and start the loop timer 205 . The micro-controller then detects whether the under cleaning mode has been selected by the user 206 . The under cleaning mode (also referred to as the “clean under” mode herein) directs the apparatus to clean areas of a room under objects. As stated earlier, the preferred embodiment considers an overhead obstruction height of less than approximately 10-12 inches over the top of the apparatus as being located under an object. The under cleaning mode is selected by the user through the selector switch 50 (visible in FIGS. 3 & 4 ). If the user has selected the under cleaning mode, the micro-controller sets the seeking job flag to true 207 . If the under cleaning mode has not been selected, the micro-controller sets the seeking job flag to false 208 . The seeking job flag status is used at various points in the clean step 213 to optimize the path of the apparatus according to the user's cleaning preference. The micro-controller then checks whether the user has changed the duration of the cleaning cycle 209 . In the preferred embodiment, the user is able to change the length of the cleaning cycle during the first ten seconds after the power switch has been pressed by triggering the collision sensors (by pressing the bumper). When the user has changed the duration by pressing the bumper, the duration of the cleaning cycle is adjusted as the loop timer that initially started in step 205 is restarted 210 . When more than ten seconds have elapsed on the loop timer 211 , the apparatus sounds a tone to announce the duration of the cleaning cycle 212 and then begins to clean 213 .
[0065] The clean step 213 is further defined in FIG. 15 to detail the specific steps that are included in the sequence. When the clean step 213 is complete, the apparatus stops the motors and restarts the loop timer 214 . The apparatus then plays a finished melody and then flashes the status light for 10 seconds 215 to alert the user that the cleaning cycle is complete and continues to do so until more than 15 minutes have elapsed on the loop timer 216 . During the 15 minute delay, the user can either shut the apparatus off using the hardware based sequence 201 by pressing the power switch or by letting the loop timer pass 15 minutes 216 . When the loop timer passes 15 minutes 216 , the apparatus shuts off the lights and powers down 217 , ending the full cleaning cycle 220 .
[0066] In FIG. 15 is a flow chart detailing the sequence used by the apparatus under the clean step 213 in FIG. 14 . After the clean step starts 221 , the micro-controller starts the duration timer 222 . The micro-controller then initiates the move forward step 223 . The move forward step is further defined in FIG. 17 to detail the specific steps that are included in the sequence. When the move forward step 223 is complete, the apparatus checks whether there is a pending fall 224 indicated by the fall sensors or if there has been a bump detected by the collision sensors 227 . If either of these conditions exist, the micro-controller turns on the trouble light 225 and initiates the backup and spin sequence 226 .
[0067] When the move forward step 223 is complete and a fall is not pending 224 and a bump has not been detected 227 , the apparatus checks whether the clean under mode has been selected by the user 228 . When the clean under mode has been selected, the apparatus checks whether the seeking job flag is set to true 229 . If the seeking job flag is set to true, it then uses the upward facing ultrasonic sensors 22 (visible in FIGS. 1 & 2 ) to determine if the apparatus is located under an object 230 . If the apparatus is under an object, the micro-controller sets the seeking job flag to false 231 .
[0068] When the apparatus is not seeking a job in step 229 , the apparatus uses the upward facing ultrasonic sensors 22 (visible in FIGS. 1 & 2 ) to determine if the apparatus is located under an object. If under an object, the micro-controller continues to the next step. If not under an object, the apparatus will backup and spin 233 , a process explained in further detail in FIG. 16 . After the backup and spin step 233 , the apparatus will again check whether it is under an object 234 . If under an object, the micro-controller will move along to the next step. If not under an object, the micro-controller will decide whether to set the seeking job flag to true before continuing 235 . In the preferred embodiment, the micro-controller decides to set the seeking job flag to true in step 235 approximately 40% of the time. The micro-controller can alternatively decide to set the seeking job flag to true in step 235 at a different frequency, such as approximately 25% of the time.
[0069] The next step in the clean flow chart is a check by the micro-controller if the duration timer that was started in step 222 is less than the cleaning cycle selected by the user in step 209 (in FIG. 14 ). If the duration timer has not exceeded the length of the cleaning cycle selected by the user, the micro-controller will loop back to the move forward step 223 . If the duration timer has exceed the length of the cleaning cycle, the micro-controller will determine once again whether it is under an object 237 . To avoid having the apparatus end a cleaning cycle under an object, the micro-controller will loop back to the move forward step 223 if located under an object at the end of the cycle. When the apparatus is not under an object and the duration timer has exceeded the duration of the cleaning cycle selected by the user, the clean step will end 240 .
[0070] In FIG. 16 is a flow chart detailing the backup and spin function 226 and 233 in FIG. 15 . When the backup and spin flow chart has been initiated 241 , the micro-controller first stops the motors 242 . The micro-controller will then decide a direction to begin a spin 243 . Approximately 70% of the time, the chosen spin direction will be in a different direction than the last spin. The micro-controller then decides on a spin speed by directing each motor to spin in an opposite direction at between 70 and 100 percent 244 , where the percentage indicates the shaft speed of the motor in relation to its maximum shaft speed under load. The variable spin rates help the apparatus free itself when it is stuck or in danger of being stuck.
[0071] To reduce the chances of the apparatus backing off or spinning off a ledge, the micro-controller then checks if it has had a recent pending fall 245 . A recent pending fall will take the form of a recent event where the downward facing infrared sensors 52 (visible in FIG. 4 ) have sensed a fall or a lack of ground under the front of the apparatus. When a recent fall has been detected, the micro-controller will direct a less aggressive backup and spin, choosing a backup time of between 0.75 to 1.50 seconds 250 and a spin time of between 0.75 and 1.50 seconds 251 .
[0072] If a recent fall has not been detected in step 245 , the micro-controller will then check if the apparatus appears to be stuck 246 . The apparatus does not need to be physically unable to move for the micro-controller to consider it stuck, but rather can be merely moving in a small partially enclosed area, such as under a chair or under a piece of furniture in a corner. The apparatus considers itself to be stuck when there have been four hits on the bumper 24 (visible in FIG. 1 ) within the previous four seconds of forward motion and the last period of forward motion was less than two seconds. The micro-controller starts a timer each time the apparatus moves forward and keeps the previous four forward elapsed times in memory on a rolling basis. When the micro-controller determines that the apparatus is stuck in step 246 , the apparatus plays a trouble melody 247 and chooses an extended backup time of between 0.50 and 3.00 seconds 248 and an extended spin time of 0.50 to 7.50 seconds 249 . If the apparatus is not stuck, the micro-controller chooses an intermediate backup time of 0.50 to 2.00 seconds 252 and an intermediate spin time of 0.25 to 5.00 seconds 253 . The micro-controller chooses an extended backup and spin time when the apparatus is stuck to remove itself from the partially enclosed area that has obstructed its movement over the previous four periods of forward motion.
[0073] Once the backup and spin times have been selected by the micro-controller, the apparatus executes the selected backup 254 . While the micro-controller will select a power level for each motor and a duration, in the preferred embodiment, the motor does not run at the selected power level for precisely the duration selected. To avoid stressing the motor and gears, the motor speeds are increased over a span of milliseconds rather than instantaneously. After the backup is complete, the micro-controller turns off the trouble light 255 (if it was energized) and directs the apparatus to execute the selected spin 256 . Once the spin is complete, the backup and spin sequence is complete 260 .
[0074] In FIG. 17 is a flow chart detailing the move forward step 223 in FIG. 15 . After the move forward sequence begins 261 , the micro-controller starts the forward timer 262 . The forward timer runs for the entire duration of each move forward sequence and provides the basis for the forward elapsed times used to choose the duration of the backup and spin in FIG. 16 . The micro-controller then polls the sensors to determine if the apparatus is about to fall 263 or if the collision sensors have been triggered 264 . Either event causes the trouble light to turn on 265 , the motors to stop 280 and the move forward sequence to end 281 .
[0075] If neither a pending fall nor bump are detected, the micro-controller determines if the duration timer that was started in step 222 (in FIG. 15 ) is less than three seconds. If the duration timer is less than three seconds, the micro-controller will calibrate the fall detectors 267 by calculating and storing the maximum values recorded during the first three seconds of the duration timer. In the preferred embodiment, the fall detectors calculate a value based on the amount of time elapsed between the transmission and receipt of an infrared pulse and the intensity of the return pulse. The precise values generated by the fall detectors will depend on the specific infrared sensors (or other type of sensor capable of detecting distance) used in the application. For infrared sensors in general, surfaces that are further away generate higher values. Darker and matte surfaces generate higher values because they reflect less light than lighter and glossy surfaces, making them appear further away to an infrared sensor. The apparatus will continue to operate during the time when the micro-controller is calibrating the fall detectors to ensure that multiple areas of the surface to be cleaned are sensed in the initial calibration.
[0076] If the apparatus is stopped at step 268 , the micro-controller will start a heading timer and direct the apparatus to move forward at full speed 269 . If the apparatus is not stopped in step 268 , the micro-controller will move directly to the next step where it determines if the under cleaning mode has been selected by the user 270 . If the under cleaning mode has been selected by the user, the micro-controller will initiate the forward under sequence 274 that is shown in further detail in FIG. 18 .
[0077] If the under cleaning mode has not been selected in step 270 , the micro-controller will then determine if the heading timer has run for more than four seconds 271 . When the heading timer has run for more than four seconds, 70 percent of the time, the micro-controller will select a new forward speed, setting both motors forward at 100 percent and 30 percent of the time, the micro-controller will select a new forward speed, setting each motor forward at 60 to 100 percent 272 . Once the new forward speed is selected in step 272 , the micro-controller restarts the heading timer and directs the apparatus to move forward at the selected speed 273 .
[0078] In the next step in the move forward sequence, the micro-controller determines if the forward timer that began in step 262 has exceeded “X” seconds 275 . In the preferred embodiment, the micro-controller sets “X” to 25 so that in step 275 , the micro-controller determines whether the forward timer has exceeded 25 seconds. The micro-controller can alternatively decide to set “X” as a different value, such as 60.
[0079] When “X” seconds have elapsed, the micro-controller stops the motors 280 and the move forward sequence is ended 281 . If the forward timer has not exceeded “X” seconds in step 275 , the micro-controller then begins to determine whether the apparatus is operating in a large open space, such as under a bed or in a large room. The micro-controller first polls the upward facing ultrasonic sensors to determine if the apparatus is located under an object 276 . If under an object, the micro-controller checks if the last four forward times have all exceeded “Y” seconds 277 . In the preferred embodiment, the micro-controller sets “Y” to two so that in step 277 , the micro-controller determines whether the last four forward times have all exceeded two seconds. The micro-controller can alternatively decide to set “Y” as a different value, such as three.
[0080] If the previous four forward times have exceeded “Y” seconds, the micro-controller initiates the spiral outward sequence 279 which is shown in further detail in FIG. 19 . If the apparatus is not under an object in step 276 , the micro-controller checks if the last four forward times have all exceeded “Z” seconds 278 and uses this threshold to determine whether to initiate the spiral outward sequence 279 . In the preferred embodiment, the micro-controller sets “Z” to four so that in step 278 , the micro-controller determines whether the last four forward times have all exceeded four seconds. The micro-controller can alternatively decide to set “Y” as a different value, such as five. The move forward sequence will continue to loop back to step 263 until a pending fall 263 or bump is detected 264 or until the forward timer has exceeded “X” seconds 275 .
[0081] In FIG. 18 is a flow chart detailing the forward under step 274 in FIG. 17 . After the forward under sequence starts 285 , the micro-controller determines if the seeking job flag is set to true 286 . If set to true in step 286 , the micro-controller then determines if the apparatus is located under an object 287 . When under an object, the micro-controller starts a loop timer and directs the motors to move forward at full speed 288 . The apparatus will continue to move forward at full speed unless a pending fall is detected 294 , triggering the trouble light 297 ; unless a bump is detected 295 , also triggering the trouble light 297 ; unless the apparatus is no longer under an object 296 or if more than two seconds have passed on the loop timer 298 that was started in step 288 . When the loop timer exceeds two seconds in step 298 , the micro-controller clears the seeking job flag, restarts the forward timer that was started in step 262 in FIG. 17 , and chooses a forward speed between 60 to 100 percent for each motor 299 . The micro-controller then starts the heading timer and directs the motors to move forward at the selected speed or speeds 300 .
[0082] If the apparatus is not seeking a job in step 286 , the micro-controller determines whether the apparatus is located under an object 289 . If not under an object, 60 percent of the time, the micro-controller will set the forward timer to greater than “A” seconds to cause the forward run to end after the move forward sequence ends in step 303 and 40 percent of the time, the micro-controller will set the seeking job flag to true 301 . In the preferred embodiment, the micro-controller sets “A” to 25 so that in step 301 , the micro-controller sets the forward timer to greater than 25 seconds 60% of the time. The micro-controller can alternatively decide to set “A” as a different value, such as 60.
[0083] If the apparatus is under an object in step 289 , the micro-controller determines whether the forward timer is 10 or more seconds greater than the longest recent elapsed forward time 290 . The micro-controller records four previous elapsed forward times and compares the present forward timer to these stored values. When the forward timer is greater than 10 seconds longer than the longest recent elapsed forward time, the micro-controller sets the forward timer to greater than “B” seconds 302 to end the forward run after the forward under sequence ends 303 . In the preferred embodiment, the micro-controller sets “B” to 25 so that in step 302 , the micro-controller sets the forward timer to greater than 25 seconds. The micro-controller can alternatively decide to set “B” as a different value, such as 60.
[0084] If the forward timer is not greater than 10 seconds longer than the longest recent forward elapsed time 290 or if the apparatus is seeking a job 286 and is not under an object 287 , the micro-controller will check if the heading timer is greater than four seconds 291 . When the heading timer exceeds four seconds, 70 percent of the time, the micro-controller chooses a forward speed of 100 percent for both motors and 30 percent of the time, the micro-controller chooses a forward speed of 60 to 100 percent for each motor 292 . Once the forward speed is selected, the micro-controller starts the heading timer and directs the motors to operate at the chosen speed 293 , thus ending the forward under sequence 303 . When the heading timer has not exceeded four seconds in step 291 , the forward under sequence is ended 303 .
[0085] In FIG. 19 is a flow chart showing the spiral outward step 279 in FIG. 17 in further detail. After the spiral outward sequence is started 305 , the micro-controller starts the loop timer and directs the motors to both move forward at full speed 306 . The micro-controller then determines whether a fall is pending 307 or if a bump has been detected 308 , either event causing the trouble light to turn on 309 . If neither event has been detected, the micro-controller determines if the loop timer is greater than half the average of the last four forward spans 310 . The micro-controller will loop back to step 307 until the loop timer exceeds half of the average of the last four forward spans in step 310 . Once the loop timer does exceed half the average of the last four forward spans, the micro-controller stops the motors and restarts the loop timer 311 . To increase the randomization of the paths taken by the apparatus, the micro-controller determines the direction of the last turn taken by the apparatus 312 and selects a first turn to the left 313 or right 314 based on it being in the opposite direction to the direction of the previous turn. The apparatus also begins its turn to the left or right in steps 313 and 314 , respectively.
[0086] As the apparatus moves, the micro-controller checks whether a fall is pending 315 or a bump has been detected by the collision sensors 316 , either event causing the trouble light to turn on 317 . If the duration timer started in step 222 (in FIG. 15 ) has not exceeded the duration set by the user in step 209 (in FIG. 14 ) 318 , the apparatus will continue to move forward and slowly reduce the rate at which it is turning 320 . When initiating the first sharp turn in steps 313 and 314 , the micro-controller directs the inboard motor to stop and the outboard motor to move forward at 100 percent. To reduce the rate at which the apparatus turns, the micro-controller slowly increases the forward rate of the inboard motor (from an initial setting of zero), creating an expanding spiral shaped path.
[0087] In step 320 , the micro-controller stops and reverses the motors at regular intervals for a short duration. Stopping and reversing the motors at regular intervals during step 320 reduces the possibility of the apparatus becoming stuck on an obstruction for the remainder of the cleaning cycle. In the preferred embodiment, the micro-controller stops the motors every 10 to 20 seconds of spiraling, operates the motors in reverse for a half second to two seconds and then continues forward as before.
[0088] When the duration timer exceeds the duration set by the user 318 , the micro-controller stops the motors and clears the stored forward span counters 319 . The micro-controller then determines if the clean under mode has been selected 321 and if selected, sets the seeking job flag to true 322 prior to ending the sequence 323 .
[0089] What has been described is an apparatus for automatically cleaning floors. In this disclosure, there are shown and described only the preferred embodiments of the invention, but, as aforementioned, it is to be understood that the invention is capable of use in various other combinations and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein. | The present invention is a mobile robot with an attached cleaning element and capable of autonomously seeking areas with low overhead clearance. In the preferred embodiment is a mobile robot using an array of upward facing distance sensors in communication with a controller to detect the presence of obstructions or surfaces above the apparatus. The controller directs the movements of the mobile robot through the use of a drive system, using pattern recognition to avoid becoming stuck and using random movements to increase floor coverage. | 0 |
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/104,452 filed Oct. 16, 1998 and U.S. Provisional Patent Application Ser. No. 60/104,985 filed Oct. 20, 1998.
BACKGROUND OF THE INVENTION
1. Field
This invention relates generally to an improved polyolefin microporous breathable film and method of making same. More specifically, this invention is directed toward a process by which increased Water Vapor Transmission Rate (WVTR) and enhanced film appearance can be realized with substantially the same film formulation and orientation.
2. Background
Preparation of films having good WVTR from highly filled polymers, usually polyolefins, is well known in the art. In the past, a combination of polyolefin, usually a polyethylene, with a filler, usually CaCO 3 , is widely used as a film with good WVTR, often, but not necessarily, in combination with non-woven polymers for use in diapers, adult incontinence devices, feminine hygiene articles, surgical garments, housewrap composites, protective apparel, roofing materials and the like.
The use of interdigitating rolls to orient films or non-wovens is also well known in the art. In some cases this process is referred to as cold stretching. To increase the WVTR of films, while employing interdigitating technology, it has been necessary to increase the level of filler in the polyolefin/filler blend, or to increase the depth of interengagement of the orienting rollers—both of which have technical limits, and which may have a serious negative impact on important physical properties of the resulting film. The technical limits of depth of engagement of the interdigitating rolls and CaCO 3 loading restrict film breathability level.
Also, it is desirable for many applications of breathable film, such as disposable diapers, adult incontinence products, and feminine hygiene devices, that some visual evidence of a difference between breathable and non-breathable films exist. It is thought that this product differentiation could be of benefit to the consumer, as well as the manufacturer of the disposable products.
SUMMARY
We have discovered that applying heat to interdigitating rollers results in a substantial improvement in orientation effectiveness (WVTR increases), and imparts a third dimensionality to the film which differentiates it from other breathable films. In addition, a new control is provided for the adjustment of film breathability, i.e., rather than require a formulation change, or adjustment to the depth of activation of the interdigitating rollers, to control WVTR levels, roller temperature may be adjusted. As can be seen from the following examples, with all other factors constant, an increase in the temperature of the interdigitating rolls from 70° F. to 140° F., increases WVTR from 1900 gm/sqm/day to 4100 gm/sqm/day.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the Process for Producing Polyolefin Microporous Breathable Film may be obtained by reference to the following drawing figures together with the detailed description.
FIG. 1 shows the geometry of interdigitating rollers;
FIG. 2 shows a machine direction orientation roller;
FIG. 3 shows a transverse direction orientation roller; and
FIG. 4 shows a cross-section of a WVTR test cell.
DETAILED DESCRIPTION
Introduction
This invention concerns polyolefin/filler based breathable films. While initial work was executed on a polypropylene based product, it will be shown that the disclosed process is effective for all polyolefin materials.
This invention further includes certain polyolefins, their conversion into fabricated articles such as films, articles made from such films, and applications in which such articles having high WVTR combined with good physical properties are desirable. The resulting films, and film composites, (including coextruded and laminated films) have combinations of properties rendering them superior and unique to films or film composites previously available. The films disclosed herein are particularly well suited for use in producing certain classes of high WVTR films, consumer and industrial articles using the films in combination with, for instance, polymeric woven or non-woven materials. Such consumer articles include, but are not limited to diapers, adult incontinence devices, feminine hygiene articles, medial and surgical gowns, medical drapes, industrial apparel, building products such as “house-wrap”, roofing components, and the like made using one or more of the films disclosed herein. Additionally, the films of the present invention may also be used in metallized films with a high WVTR, according to the disclosure of U.S. Pat. No. 5,055,338, which is to be incorporated herein by reference in its entirety.
Production of the Films
Films contemplated by certain embodiments of the present invention may be made utilizing a polyolefin, by film processes including blown molding, casting, and cast melt embossing. The preferred process is a cast melt embossed film process. In extrusion processes, the films of the present invention can be formed into a single layer film, or may be one layer or more of a multi-layer film or film composite. Alternatively, the polyolefin films described in this disclosure can be formed or utilized in the form of a resin blend where the blend components can function to modify the WVTR, the physical properties, the draw-down, the sealing, the cost, or other parameters. Both blend components and the parameters provided thereby will be well known to those of ordinary skill in the art. The breathable films of the present invention may also be included in laminated structures. As long as a film, multi-layer film, or laminated structure includes one or more polyolefin/filler film layers having the WVTR, or draw-down, and the like of the film, such film, multilayer film, or laminated structure will be understood to be contemplated as an embodiment of the present invention.
Polyolefin Precursor Film Component
The polyolefin precursor component can be any film forming polyolefin including polyethylene and polypropylene, ethylene polar comonomer polymers, ethylene α-olefin copolymers and combinations hereof.
Suitable Polyolefins and Relative Benefits
Polypropylene
Impact
Tear
Softness
Drawdown
Metallocene Homo-
preferred
preferred
preferred
most
polymers and
preferred
Copolymers
Random Copolymer
more
more
more
more
PP
preferred
preferred
preferred
preferred
Impact Copolymer
most
most
most
preferred
polypropylene
preferred
preferred
preferred
Homopolymer PP
preferred
preferred
preferred
preferred
Exxon LD 3003
preferred
preferred
preferred
preferred
It will be understood that, in general, we contemplate that a large number of polyolefins will be useful in the techniques and applications described herein. Also included in the group of polyolefins that are contemplated as embodiments of this invention are metallocene catalyzed polyethylenes, both linear low density and very low density (0.88 to 0.935 g/cm3), high density polyethylene (0.935-0.970 g/cm3), Ziegler-Natta catalyzed linear low density polyethylene, conventional high pressure low density polyethylene (LDPE), and combinations thereof. Various elastomers or other soft polymers may be blended with the majority polyolefin component, these include styrene-isoprene-styrene (styrenic block co-polymer), styrene-butadiene-styrene (styrenic block co-polymer), styrene-ethylene/butylene-styrene (styrenic block co-ploymer), ethylene-propylene (rubber), Ethylene-propylene-diene-modified (rubber), Ethylene-vinly-acetate, Ethylene-methacrylate, Ethylene-ethyl-acrylate, Ethylene-butyl-acrylate.
Filler
Fillers useful in this invention may be any inorganic or organic material having a low affinity for and a significantly lower elasticity than the film forming polyolefin component. Preferably a filler should be a rigid material having a non-smooth hydrophobic surface, or a material which is treated to render its surface hydrophobic. The preferred mean average particle size of the filler is between about 0.5-5.0 microns for films generally having a thickness of between about 1 to about 6 mils prior to stretching.
Examples of the inorganic fillers include calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium, sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, zinc oxide, magnesium hydroxide, calcium oxide, magnesium oxide, titanium oxide, alumina, mica, glass powder, zeolite, silica clay, etc. Calcium carbonate (CaCO 3 ) is particularly preferred for its low cost, its whiteness, its inertness, and its availability. The selected inorganic filler such as calcium carbonate is preferably surface treated to be hydrophobic so that the filler can repel water to reduce agglomeration. Also, the surface treatment of the filler should improve binding of the filler to the polyolefin precursor while allowing the filler to be pulled away from the precursor film under stress. A preferred coating for the filler is calcium stearate which is FDA compliant and readily available.
Organic fillers such as wood powder, and other cellulose type powders may be used. Polymer powders such as Teflon® powder and Keviar® powder can also be used.
The amount of filler added to the polyolefin precursor depends on the desired properties of the film including dart impact strength, tear strength, WVTR, and stretchability. However, it is believed that a film with good WVTR generally cannot be produced as is taught herein with an amount of filler less than about twenty percent (20%) by weight of the polyolefin/filler blend.
The minimum amount of filler (about twenty percent by weight) is needed to assure the interconnection within the polyolefin precursor film of voids created at the situs of the filler—particularly by the stretching operation to be subsequently performed. Further, it is believed that useful films could not be made with an amount of the filler in excess of about seventy percent (70%) by weight of the polyolefin/filler composition. Higher amounts of filler may cause difficulty in compounding and significant losses in strength of the final breathable film. Preferred ranges include about 30% to about 70% by weight, more preferably from about 40% to about 60% by weight.
While a broad range of fillers has been described at a broad range of inclusion parameters based on weight percentages, still other embodiments of the present invention are contemplated. For instance, fillers with much higher or much lower specific gravity may be included with the polyolefin precursor at amounts outside the weight ranges disclosed. Such combinations will be understood to be contemplated as embodiments of our invention as long as the final film, after orientation, has WVTR, or draw down similar to that described herein.
Film Physical Property Modification
It was found that the addition of small amounts of low density polyethylene to the polyolefin/filler blend allowed film extrusion at higher throughput levels with some majority polymers. Low density polyethylene with a melt flow index of about 0.9 to 25.0 grams per ten minutes (12.0 grams per ten minutes being preferred), and a density of about 0.900 to 0.930 may be used.
Further improvements in film impact and tear strength are possible by the addition of plastomers, elastomers, styrenic block co-polymers (SIS, SBS, SEBS), or rubbers. Material grades included are:
Property Improvement Materials
Melt Flow
Supplier
Grade
Index
Density
Exxon Chemical
Exact 3139
7.5
.900
Exxon Chemical
Exact 4044
16.5
.895
Exxon Chemical
Exact 9095
2.2
.893
Exxon Chemical
Exact 3131
3.5
.900
Exxon Chemical
Paxon SLX 9106
2.0
.900
Exxon Chemical
Paxon SLX 9101
3.5
.900
Dexco
Vector 4211
13
Dexco
Vector 4411
40
Exxon
Vistalon 3708
Exxon
Vistalon 3030
Shell
Kraton G1657
8
SEBS
Union Carbide
UC 9042
5.1
.900
Union Carbide
UC 1085
0.8
.884
Stretching or Orienting
Final preparation of a breathable film is achieved by stretching the filled polyolefin precursor film to form interconnected voids. Stretching or “orientation” is achieved by incrementally orienting the polyolefin precursor in the machine direction, transverse direction, or both. Films can be incrementally oriented by a number of mechanical techniques, however, the preferred technique is to stretch the film through pairs of interdigitating rollers, as shown in FIG. 1 . Therein it may be seen that the film is contracted by the apex 18 of a plurality of teeth spaced a distance or pitch (W) apart. The apex 18 of each tooth extends into the open space 20 between the teeth on an opposing roller. The amount of interengagement depends both on the tooth depth (d) and the relative position of the rollers.
Machine direction orientation is accomplished by stretching the film through a gear like pair of rollers 16 as shown in FIG. 2 . Transverse direction orientation is accomplished by stretching the film through a pair of disk-like rollers as shown in FIG. 3 .
The preferred embodiment employs rollers with a tooth pitch, W=0.080″, however a pitch of about 0.040″ to 0.500″ is also acceptable. The tooth depth (d), is preferably 0.100″, however, a tooth depth of about 0.030″ to 0.500″ is also acceptable. For the transverse direction orientation rollers, as shown in FIG. 3, the depth may be up to about 1.000″ as mechanical interference is less of an issue with the transverse direction rollers. The preferred embodiment employs interdigitating rollers that can be temperature controlled from about 50° F. to about 210° F. More preferred is a temperature range of from about 70° F. to about 190° F. Even more preferred is a temperature range from about 85° F. to about 180° F. And most preferred is a temperature range from about 95° F. to about 160° F. Roll temperature may be maintained through the internal flow of a heated or cooled liquid, an electrical system, an external source of cooling/heating, combinations thereof, and other temperature control and maintenance methods which will be apparent to those of ordinary skill in the art. The preferred embodiment is internal flow of a heated or cooled liquid through the rollers.
The depth of interengagement of the roller teeth determines the amount of orientation imparted on the film. A balance must be drawn between the depth of engagement of the roller teeth and the level of filler in the film, as many physical properties of the film are affected as depicted in the following table.
Relationships Between Process and Formulation Factors
Relationships between process and formulation factors
Dart
Basis
CD
Adjust
WVTR
Impact
Weight
Tensile
MD Tear
CaCO 3
Increase
Increase
Increase
de-
crease
MD
Increase
Increase
de-
de-
de-
Orientation
crease
crease
crease
TD
Increase
Increase
de-
de-
De-
Orientation
crease
crease
crease
Roll
Increase
In-
de-
Temperature
creased
crease
Properties of Films Produced
WVTR
In an embodiment of the present invention, certain films and articles made therefrom have higher WVTR than previously thought possible. The WVTR of such films should be above about 100 g/m 2 /24 hr@37.8° C., 100% RH, preferably above about 1000 g/m 2 /24 hr@37.8° C., 100% RH, more preferably above about 2000 g/m 2 /24 hr@37.8° C., 100% RH. Some applications benefit from film with a WVTR at or above about 10,000 g/m 2 /24 hr@37.8° C., 100% RH.
Test Methods
Water Vapor Transmission Rate (WVTR)
Both a Mocon W1, and a Mocon W600 instrument are used to measure water evaporated from a sealed wet cell at 37.8° C. through the test film and into a stream of dry air or nitrogen. It is assumed that the relative humidity on the wet side of the film is near 100%, and the dry side is near 0%. The amount of water vapor in the air stream is precisely measured by a pulse modulated infra red (PMIR) cell. Following appropriate purging of residual air, and after reaching a steady state of water vapor transmission rate, a reading is taken. WVTR of the test films are reported at Grams of Water/Meter 2 /Day@37° C. The output of the unit has been calibrated to the results obtained with a film of known WVTR. The testing protocols are based on ASTM 1249-90 and the use of a reference film, such as Celgard 2400, which has a WVTR of 8700 g/m 2 /day@37.8° C. The diagram depicted in FIG. 4 illustrates the basic operation of the Mocon units.
Mocon W1
As illustrated generally by reference to FIG. 4, the Mocon W1 has a single test cell and an analog chart recorder. Air is pumped through a desiccant dryer, then through the test cell, and then past the PMIR sensor. A five-minute purge of residual air is followed by a six-minute test cycle with controlled air flow. The result is a steady state value for WVTR. The purge and test cycles are controlled manually. The unit is calibrated to a film with a known WVTR every twelve hours. Calibration results are control charted and adjustments are made to the instrument calibration accordingly.
Mocon W600
The Mocon W600 has six measurement cells with PMIR data fed into a computer. Nitrogen is fed through a desiccant dryer, then through the active test cell, then past the PMIR sensor. In addition to data compilation, a computer controls test cycle sequencing. All cells are purged simultaneously for an eight-minute period. This is followed by an eight-minute test cycle for each of the six measurement cells. Total testing time is fifty-six minutes. Two of the six measurement cells always measure reference films with a known WVTR.
EXAMPLES
Example 1
Experimental Grade 400-6-1
A blend of 57% ECC FilmLink 400 CaCO 3 was combined with 33% Exxon PD 7623 Impact Copolymer, 2% Exxon LD-200.48, and 8% Exxon Exact 3131 oriented in interdigitating rolls of 0.80″ pitch. The MD depth of engagement was 0.020″, and the TD depth of engagement was 0.040″. The temperature of the interdigitating rolls was 140° F.
Example 2
Experimental Grade 400-6-2
A blend of 57% ECC FilmLink 400 CaCO 3 was combined with 33% Exxon PD 7623 Impact Copolymer, 2% Exxon LD-200.48, and 8″ Exxon Exact 3131 oriented in interdigitating rolls of 0.080″ pitch. The MD length of engagement was 0.020″, and the TD depth of engagement was 0.040″. The temperature of the interdigitating rolls was 110° F.
Example 3
Experimental grade 400-6-3
A blend of 57% ECC FilmLink 400 CaCO 3 was combined with 33% Exxon PD 7623 Impact Copolymer, 2% Exxon LD-200.48, and 8% Exxon Exact 3131 oriented in interdigitating rolls of 0.080″ pitch. The MD depth of engagement was 0.020″, and the TD depth of engagement was 0.040″. The temperature of the interdigitating rolls was 70° F.
As can be seen from the following table, the WVTR rise from a roll temperature of 70° F. (considered ambient temperature) to 110° F., and then 140° F. is dramatic, unexpected and surprising.
Table of Example Film Properties
Example 1
Example 2
Example 3
Grade Number
400-6-1
400-6-2
400-6-3
Roll Temperature (° F.)
140
110
70
Basis Weight (gm/sqm)
43
40
39
WVTR (gm/sqm/day)
4100
3000
1900
Dart Impact Strength (gm)
240
300
300
MD Ultimate (gm/in)
1585
1532
1453
MD Elongation (%)
408
431
442
TD @ 5% (gm/in)
457
389
388
TD Ultimate (gm/in)
785
1166
1049
TD Elongation (%)
351
358
357
MD Elmendorf Tear Strength (gm)
166
208
205
A linear regression analysis reveals that with the above fixed formulation, depth of activation water vapor transmission rate is predicted by the following equation:
WVTR= −329.73+31.216*Roller Temperature (° F.)
Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims. | Polyolefin/filler breathable films may be produced by machine or transverse direction orientation using interdigitating grooved rollers. Biaxial orientation to similarly produce breathable films may be accomplished by the same method. By heating the rollers, the breathability of the film is increased without increasing the depth of engagement of the interdigitating rollers. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to new and useful improvements in squeeze gate assemblies used for cattle normally in conjunction with a head gate assembly at one end thereof.
Many squeeze gates exist, but all suffer from disadvantages some of which include the fact that the movement of the squeeze gates lifts the cattle from the ground, operation of the squeeze gates frightens the cattle with the possibility of damage occurring to the cattle.
Other disadvantages include inefficient locking devices which not only are difficult to operate, but do not permit the squeeze gate sides to be swung open clear of the animal so that it may readily be disengaged from the chute.
SUMMARY OF THE INVENTION
The present invention overcomes these disadvantages by providing a quietly operating, easily actuated, squeeze gate in which the two sides move parallel to one another, either towards or away from each other with a simple handle operation.
The handle incorporates a self-locking assembly which, when the handle is raised to move the gate, disengages the assembly and which engages the assembly thus locking the gate, when the handle is lowered.
Another advantage of the present invention is that the two gates move towards or away from one another merely by actuating one side thereof, a cross-over chain assembly transferring similar motion to the opposite gate.
Another advantage of the present construction is that the gates are mounted on links attached to the base frame and the rear links can readily be detached so that the gate sides may swing open hinging around the front linkage thus enabling the chute to be opened fully merely by pulling the pins securing the rear linkage.
A still further object of the invention is to provide a device of the character herewithin described which is simple in construction, economical in manufacture and otherwise well suited to the purpose for which it is designed.
With the foregoing objects in view, and other such objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings in which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of the squeeze chute showing the gates in the opened position.
FIG. 2 is a top plan view of FIG. 1, but showing the gates in the squeezed or closed position.
FIG. 3 is an enlarged fragmentary top plan view showing the interconnection between the two gates.
FIG. 4 is an enlarged fragmentary side elevation showing the preferred embodiment of the rear hinging mechanism.
FIG. 5 is an enlarged fragmentary view showing the pivotal connection of the front linkage attachment to the gate.
FIG. 6 is an enlarged fragmentary side elevation showing the lock assembly.
FIG. 7 is a top plan view of FIG. 6 substantially along the line 7--7 of FIG. 6.
In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
Proceeding therefore to describe the invention in detail, reference character 10 illustrates a base frame which consists of a pair of spaced and parallel members 11 extending longitudinally and having a rear cross bar 12 extending therebetween. A head gate assembly 13 is situated at the front end of the base frame and extends upwardly therefrom but as this does not form part of the present invention, it is not believed necessary to disclose details thereof except to say that the assembly enables an animal within the chute to be engaged around the neck in the usual manner.
The head gate assembly includes a pair of spaced and parallel vertical members 14 which are preferably but not necessarily, tubular members extending upwardly from the front ends of the longitudinally extending base frame members 11.
A pair of squeeze gates collectively designated 15 are provided and are pivotally secured to the base frame for movement towards and away from one another as will hereinafter be described.
Each component 15 is substantially rectangular when viewed in side elevation and includes a rear vertical member 16, a front vertical member 17 and upper and lower horizontal members 18 and 19 with horizontal cross braces 20 being provided where necessary. The plywood panel or the like 21 may fill in the bottom portion of the open rectangular component 15.
Linkage secures the gate component 15 to the base frame 10 and dealing first with the rear linkage collectively designated 22, a pair of spaced and parallel side plates 23 are welded towards the rear end of the lower horizontal member 19 of the component 15 within which a link 24 is pivotally secured by means of pivot pin 25. The link 24 is shown in detail in FIG. 4 and consists of a cranked member, the outer end of which is secured to a vertical sleeve 26.
A plate 27 is welded to the base member 10 adjacent the rear end thereof and includes a tubular portion 28 welded to the underside thereof.
A pivot pin 29 detachably engages through the tubular member 26 and into the tubular member 28 thus detachably securing the link to the base frame member 10, but enabling same to swing free if the pivot pin 29 is removed, and in this connection the upper end of the pivot pin is angulated to form a handle portion 29A.
The front linkage collectively designated 30 includes upper and lower link arms 31 secured to a vertical support member 32 as by welding and extending outwardly therefrom. Pairs of plates 33 are welded to the front vertical member 17 of the gate component and pivot pins 34 pivot the distal ends of the link arms 31 within the pairs of plates 33 as clearly shown in FIG. 5.
The vertical support member 32 is preferably tubular and engages over the lower end bearing member 35 and is supported for rotation within a strap bearing 36 secured adjacent the upper end of the support 14 and extending rearwardly therefrom as clearly shown in FIG. 1.
Means are provided to partially rotate one of the support members 32 within its bearings, taking the form of a handle assembly 37 hereinafter to be described and further means collectively designated 38 are provided to transfer the motion of one of the support members 32 to the other 32A and hence movement of one gate component 15 to the other gate component 15A and details of this action are shown in FIG. 3.
A sprocket gear or wheel 39 is secured to the upper end of each of the support members 32 and 32A and an endless sprocket chain assembly 40 extends around the sprockets as clearly illustrated with the assembly being crossed intermediate the sprockets so that the sprockets rotate in opposite directions one to the other. This assembly 40 can be continuous length of chain, but preferably solid central rod portions 41 are preferred where the assembly crosses over in order to prevent any locking up of the assembly from occurring.
Referring back to the handle assembly 37, this includes the elongated handle 42 pivoted for movement within a vertical plane by the inner end thereof, within a portion 43 secured to and extending from one of the support members 32.
A lock means or assembly is provided collectively designated 44 and takes the form of a quadrant 45 secured by one end thereof to the support 13 and curving around the support member 32. A plurality of apertures 46 is formed through this quadrant as clearly shown in FIG. 7.
A curved guide 47 extends upwardly from the portion 43 and over the quadrant 45 and supports a relatively short pin 48 for vertical sliding movement and this pin is positioned so that it may engage any of the apertures 46 within the quadrant 45 when it is in the lowermost position as illustrated in FIG. 6.
A relatively long pin 49 is also provided and pins 48 and 49 are connected together by a connector link 50 and pin 49 extends downwardly just clear of the portion 43 to which handle 42 is pivoted.
The relatively long pin 49 is positioned so that it is engaged by the handle when the handle is raised to the horizontal or operating position shown in FIG. 1 and this raises pin 49 upwardly in the direction of arrow 51 together with short pin 48 and link 50 thus disengaging the short pin 48 from the quadrant and allowing the support member 32 to be rotated by means of the handle 42.
Movement of the handle in the direction of arrow 52 as illustrated in FIG. 2, will cause the two support members to rotate thus moving the gate components 15 and 15A inwardly towards one another to the position shown in FIG. 2 whereupon lowering of the handle 42 will enable the short pin 48 to move downwardly and engage one of the apertures 46 within quadrant 45 thus locking the squeeze gate in the desired position so that the gate components 15 and 15A cannot move outwardly relative to one another.
When it is desired to release the gate components 15 and 15A, the handle may be raised to the horizontal position thus disengaging pin 48 whereupon the handle can be moved in a direction opposite to arrow 52 thus opening the gates which of course remain substantially parallel to one another at all times due to the position of the front and rear linkage as hereinbefore described.
If desired, the animal held between the gates in the locked position, may be released merely by pulling the pivot pin 29 of the rear linkage 23 as hereinbefore described whereupon the two gate components may swing outwardly away from one another pivoting upon the pivot pins 34 of the front linkage 30. This enables the animal to be released immediately, assuming that the head gate assembly has also been released.
From the foregoing, it will be appreciated that operation of the squeeze gate assembly is easily controlled by a single operator who can also operate the head gate assembly and that the two squeeze gate components move in a parallel movement one with the other towards or away from one another thus enabling the animal to be held firmly yet released readily and rapidly.
Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. | Two gate sides are pivoted within a base for substantial parallel swinging movement towards and away from one another by means of a handle on one support post of the components. A cross-over chain at the other ends of said support posts transfers movement of one gate side with the other. The handle incorporates a locking mechanism which is disengaged when the handle is lifted for gate side movement but is engaged when the handle is lowered thus maintaining the gate side lock in position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No. 10/796,353, filed Mar. 8, 2004 now U.S. Pat. No. 7,028,818.
FIELD
The embodiments of the invention relate to terminating signals. Specifically, embodiments of the invention relate to terminating signals with a programmable on die termination circuit to maximize transfer rates.
BACKGROUND
Computer systems are comprised of a set of components that communicate with each other over buses and similar communication lines. Computer system components include processors, communication chipsets, memory modules, peripheral components and similar devices. These devices communicate with one another over a set of buses. These busses may utilize communication protocols understood by each of the components on the bus. Some components act as bus controllers to manage communication traffic on the bus.
Computer system speed and efficiency is limited by the speed of buses and communication lines in the computer system. A processor relies on a system bus, memory bus and memory controller for retrieving data and instructions from system memory. The processor is limited in the speed at which it can process these instructions by the speed at which it can receive the data and instructions over the system bus and memory bus from system memory.
Buses are typically communication lines laid out on a printed circuit board such as the main board of a computer system. Components in the computer system have pins that connect to the lines of the bus. The components communicate across the bus by driving a signal across lines of the bus. These signals are latched by a recipient device. The signal is terminated by an on board termination circuit which includes a resistor or similar component. If a signal is not properly terminated then a reflection of the signal may occur or other noise may affect subsequent signaling on the line.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
FIG. 1 is a block diagram of one embodiment of a computer system.
FIG. 2 is a block diagram of one embodiment of a communication line between a memory controller and a memory module.
FIG. 3A is a diagram of one embodiment of the behavior of a signal on a communication line utilizing an on die termination circuit.
FIG. 3B is a diagram of one embodiment of the behavior of a signal on a communication line with programmed on die termination.
FIG. 4 is a diagram of one embodiment of a feedback test circuit.
FIG. 5 is a diagram of one embodiment of a circuit for programmable one die termination of a signal.
FIG. 6 is a diagram of one embodiment of circuit for converting a format of an encoded condition signal.
FIG. 7 is a flowchart of one embodiment of a process for terminating a signal on die.
DETAILED DESCRIPTION
FIG. 1 is a block diagram of one embodiment of a computer system. In one embodiment, the computer system may include a processor 101 for executing instructions of programs. Program instructions may be retrieved from memory 113 or similar sources. The computer system may include multiple processors. In one embodiment, processor 101 may be in communication with a hub 107 . Hub 107 may facilitate communication between processor 101 , memory 113 , graphics processor 109 and similar input and output devices. In one embodiment, hub 107 may be a component or chipset on a mainboard or similar platform. Hub 107 may be a “Northbridge” chipset. In one embodiment, graphics processor 109 may be a component or chipset on a mainboard or similar platform. In another embodiment, the graphics processor 109 may be on a peripheral card connected to the mainboard or platform via an accelerated graphics port (AGP) or similar connection. Graphics processor 109 may be in communication with a monitor 111 or display device. A display device may be a cathode ray tube (CRT) device, liquid crystal display device, plasma display device or similar display device.
In one embodiment, hub 107 may be in communication with input output (I/O) hub 115 . I/O hub 115 may facilitate communication between hub 107 and I/O devices 119 , storage devices 117 and similar devices. In one embodiment, I/O hub 115 may be a component or chipset on a mainboard or similar platform. I/O hub 115 may be a “Southbridge” chipset. I/O hub 115 may be in communication with a communications device 121 . Communications device 121 may be a network card, wireless device or similar communication device.
In one embodiment, the computer system may be connected to a network 123 through communications device 121 . The computer system may communicate through network 123 with a remote system such as a computer system, console device, handheld device, sensor or similar system.
FIG. 2 is a diagram of one embodiment of a communication line between a memory controller and a memory module. In one embodiment, a memory module 211 communicates with memory controller 213 via a communication line 205 . A memory module 211 may be a dynamic random access memory module or similar memory module type. The memory module may be packaged as a dual in line memory module (DIMM), single in line memory module (SIMM) or similar memory module configuration. Memory module 211 may be a double date rate (DDR) module or similar type of memory module. In one embodiment, memory controller 213 may be a direct memory access (DMA) controller, NorthBridge chipset or similar device. Communication line 205 may be a part of a system bus such as a front side bus, a memory bus, or similar communication line. The diagram shows a single communication line. Memory module 211 and memory controller may communicate over any number of communication lines in parallel or in similar configurations.
In one embodiment, memory module 211 has a set of driving circuits 201 , 203 to drive a signal over communication line 205 . Memory module 211 may have a set of logic one circuits 201 to drive a logical ‘one’ signal over communication line 205 . For example, the logical one signal may be a relative high voltage signal. In one embodiment, memory module 211 may have a set of logic zero circuits 203 to drive a logical ‘zero’ signal over communication line 205 . For example, the logical zero signal may be a relative low voltage signal.
In one embodiment, memory controller 213 or similar receiving circuit may be connected to communication line 205 . Any circuit chip, or component may be coupled to communication line 205 and receive a signal sent by another chip, component, or circuit. For example, memory module 211 may send a set of signals to memory controller 213 where communication line 205 is part of a memory bus.
In one embodiment, a receiving circuit must terminate an incoming or received signal to prevent reflection of the signal and noise on communication line 205 . A receiving device such as memory controller 213 may utilize a set of resistors 207 to terminate the incoming signal. Resistor 207 must have a resistance of appropriate size to terminate the signal properly. In another embodiment, communication line 205 may be bidirectional. A terminations circuit may be utilized at both the receiving circuit and the driving circuit.
FIG. 3A is a diagram of the behavior of a signal on a communication line utilizing known on die termination circuits. The diagram shows the relative current (I) and voltage (V) of a signal that is received by a device when the signal transitions from a high voltage to a low voltage. The diagram shows a signal when the resistance of the line receiver is not attuned to the conditions of the line or the strength of the incoming signal. This results in a transition period 301 , such as a change in voltage level in a signal, exhibiting fluctuations in the resistance to a signal. The resistance is the relationship between the current and voltage that the diagram shows as a curved line. This behavior of known on die termination circuits is undesirable because it does not maintain a constant relationship between current I and voltage V during periods of voltage change 301 to minimize signal reflection and maximize the signaling rate of a communication line.
FIG. 3B is a diagram of the behavior of a signal on a communication line with programmable on die termination. The diagram shows a signal where the on die termination has been calibrated for the conditions of the chip. The transition period of the signal 303 exhibits a constant resistance. The constant resistance facilitates the termination of the signal as the strength of the signal is fully absorbed by the on die termination circuit. This allows higher communication speeds on the communication line. Higher communication speeds are possible because the communication line may be available to transmit the next signal in a shorter time period. A communication line may be unavailable or unusable when signal reflection and similar noise occurs on a line due to poor termination of the previous signal. If the previous signal is properly terminated with a constant resistance to the signal over the transition of the signal from one voltage level to another voltage level then the communication line may be used for transmitting the next signal without an extensive delay to allow for signal reflection and similar noise to subside. This improved performance may be attained without the need for the extra board area and added component cost required by on board termination.
FIG. 4 is a diagram of one embodiment of a condition testing circuit. In one embodiment, a device may include a testing circuit 401 to determine conditions in the device. A device may be any component chip or similar device that communicates with other devices in a computer system. For example, a device may be a memory controller or similar device. The testing circuit may include test block or circuit block 403 including a block of circuits that are representative of other circuit blocks in the device. Circuit block 403 may be part of a feedback loop 409 that receives an off die signal or power source and includes a finite state machine 405 .
In one embodiment, finite state machine 405 monitors the signals in the feedback loop and functions as an encoder that generates an encoding for the conditions of circuit block 403 . The conditions that finite state machine 405 may encode include the effects of the physical characteristics of the device, such as the quality and type of manufacture, materials and similar physical characteristics, temperature, voltage and similar device conditions have on the signal processed by circuit block 403 . In one embodiment, finite state machine 405 may encode the impedance of signals in block 403 based on physical characteristics, voltage levels, and temperatures (PVT) of block 403 . Finite state machine 405 may encode the conditions in a signal output to an internal communication line 407 . This signal may be used by compensation circuits to adjust the operation of other blocks in the device to correct for conditions in the device and thereby improve the performance of the device.
In one embodiment, the conditions in the device may be encoded in an 8 bit format. In another embodiment, the conditions may be encoded in any sized signal or format. This signal may be used to drive adjustment circuits in other blocks. The encoded condition may have a more precise encoding of the conditions than are utilized by the adjustment circuits in the other parts of the device. For example, the testing circuit 401 may generate an 8 bit encoding of the device conditions. The adjustment circuits may only utilize an approximated 5 bit encoding of the conditions in the device. In one embodiment, a device may have multiple testing circuits. The outputs of these circuits may be utilized for different regions of the device. In another embodiment, the output of multiple testing circuits may be combined for a composite condition encoding.
FIG. 5 is a diagram of one embodiment of an on die termination circuit having a driver circuit to adjust the resistance to an incoming signal. In one embodiment, termination circuit 500 may be electrically coupled to an input pad 507 . Input pad 507 may be connected to a pin or similar structure that is coupled to a communication bus to receive a signal from other devices. Input pad 507 may be coupled to on die termination circuit 500 . On die termination circuit 500 may absorb the incoming signal to prevent the reflection of the signal and to minimize noise on the communication line.
In one embodiment, a receiving circuit or input pad 507 may be coupled to a set of resistors 509 . In one embodiment, set of resistors 509 may include three resistors for absorbing incoming signals. The three resistors may be polyresistors. In one embodiment, the resistors may be composed of polysilicide or similar material. Set of resistors 509 may have an overall resistance to an incoming signal that is based on the strength of signal generating devices. In one embodiment, the distribution of the resistance between the resistors may be use to adjust the properties of on die termination circuit 500 . In one embodiment, the resistor coupled in series with the other resistors and positioned on the input pad leg of the circuit may have a proportionately large size in comparison with the parallel resistors coupled to transistor sets 503 , 505 . In this configuration the resistance of on die termination circuit 500 to an incoming signal exhibits a greater linearity than if a greater proportion of the resistance was placed in the resistors in series coupled to transistor sets 503 , 505 .
In another embodiment, the distribution of the resistance amongst resistors 509 may be used to improve the range of resistance that can be provided. In this embodiment, larger matching resistors are used in series in the legs of set of resistors 509 that are coupled to set of transistors 503 , 505 than in the input pad leg. In this configuration a greater range or resistances can be provided to allow more programmable resistance settings.
In one embodiment, the resistance to the incoming signal is added to and configurable based on sets of transistors 503 and 505 . Transistor set 503 may be a set of PMOS transistors that form a pull up resistor in combination with the resistor from the set of resistors 509 coupled to the set of PMOS transistors. A set of complementary NMOS transistors 505 may be coupled to the other parrallel leg of the set of resistors 509 to form a pull down resistor. The sets of transistors 503 , 505 may be programmed by a driver signal 501 generated by the testing circuit or similar signal source. Driver signal 501 may activate or deactivate a complementary set of transistors from PMOS and NMOS transistors 503 , 505 to vary the resistance provided by the pull up and pull down resistors. Driver signal 501 may be based on the conditions of the device and thereby adjust the resistance to properly terminate an incoming signal based on the conditions of the device. These conditions may change dynamically and driver signal 501 may dynamically alter the resistance of the on die termination circuit 500 accordingly to allow transistor sets 503 , 505 to act as a compensation circuit. Transistor sets 503 , 505 may be isolated from input pad 507 by resistors 509 to minimize the resistive value of the transistors due to voltage changes at the input pad.
FIG. 6 is a block diagram of one embodiment of a conversion circuit to convert a condition code into a driver signal for an on die termination circuit. In one embodiment, a device or chip may generate a condition code having greater precision than supported by an on die termination circuit. In one embodiment, an encoded condition signal is in an 8 bit form. For example, a 865/875 chipset from Intel Corporation, stores an 8 bit condition encoding in an rcomp register which may be used by the on die termination circuit. In one embodiment, the on die termination circuit may utilize a 5 bit driver signal. A conversion circuit may approximate the 8 bit signal in a 5 bit form. In one embodiment, an on die termination circuit may utilize an approximated or truncated condition code because a small number of legs in the driver circuit are used to conserve space on die.
In one embodiment, condition code signal 617 may be input into a multiplier 601 . Multiplier 601 may adjust the encoded signal by multiplying the signal to adjust for the conditions of the on die termination circuit based on the relation of the voltage level at which the signal was encoded to the voltage level of the on die termination circuit. For example, if the voltage level of condition code signal 617 is twice the voltage level of the on die termination circuit the multiplier may be a ½ or 0.5 multiplier. Multiplier 601 may have a set number of multipliers that may be applied to the incoming condition code signal 617 . For example, multiplier 601 may support ½, ⅝, ¾, ⅞, 1, 9/8, 5/4, and 3/2multiplications of the encoded condition signal 617 . In one embodiment, an offset or adder component 603 may be used to further modify the encoded signal to compensate for differences in the operation, voltage level, characteristics and similar conditions of the on die termination circuit. Offset component may be used to make a static adjustment to encoded condition signal 617 .
In one embodiment, a manual or test mode may be supported by a device. In a manual, test or similar scenario an override mode may be used to directly set the condition code for the device thereby ignoring the actual device conditions. In one embodiment, override setting signal 613 supplies the replacement condition code. The replacement condition code may be provided in a format intended for other components of the device and may need to be adjusted in the same manner as the encoded condition signal. In another embodiment, the replacement condition code may be supplied in a format directly useable by the on die termination circuit. A multiplexor 605 , switch or similar circuit driven by an override command signal 611 may choose between the override settings signal 613 and the adjusted condition code signal 617 .
In one embodiment, a further set of checks may be made of the adjusted condition code signal. In one embodiment, an approximation check may be made. If the highest order bits of a condition code are not used in the approximated signal an approximation check may designate a set value to be utilized for all adjusted condition codes that have logic ‘one’ values in the highest order bits that are not utilized in the approximated driver signal. For example, if an 8 bit encoding is being approximated by a 5 bit encoding by utilizing all the bits of the 8 bit encoding except for the highest order bit and the two lowest order bits, then an approximation check determines if the highest order bit is a logical one. If the bit is a one then the highest approximated value may be used, such as an all logical ones 5 bit value ‘11111.’ Multiplexor 607 may select between the designated replacement value and the adjusted condition code signal 607 based on detection of a high order ‘1’ bit or similar approximation triggering condition.
In one embodiment, the approximation check may also include an overflow check. An overflow check may be made to determine if the multiplier component 601 or offset component 603 caused condition code signal 617 to overflow. The overflow check component may test to determine if the multiplier component 601 or offset component 603 cause the highest order bit in condition code signal 617 to change from a logical 1 to a logical 0 due to the overflow. In one embodiment, this overflow error may be corrected for by designating an encoding to approximate all the high value condition codes that result from an overflow. For example, an all logical ones ‘11111’ value may be used in a 5 bit encoding for all adjusted condition codes that generated an overflow signal during multiplication or offset. Multiplexor 607 may select between the designated replacement value for approximation checks and the actual adjusted condition code signal to be output to the on die termination circuit based on the detection of an overflow.
FIG. 7 is a flowchart of one embodiment of a process for programming an on die termination circuit to adjust for conditions in a chip or device. In one embodiment, a testing circuit or similar component detects the physical conditions, voltage conditions and temperature conditions (PVT) of the component or on die termination circuit (block 701 ). After the PVT conditions have been detected an encoded signal representing the signal may be generated by a testing circuit or similar circuit (block 703 ).
In one embodiment, the encoded condition signal may be used as a driver signal to adjust the on die termination circuit. In another embodiment, the encoded condition signal may need to be converted into a format suitable for driving the on die termination circuit (block 705 ). The driver signal may be used to set the resistance level of the on die termination circuit based on device conditions. An input signal may be received by the on die termination circuit at an input pad (block 707 ). The properly adjusted on die termination signal then terminates the incoming signal by providing a constant resistance at a sufficient level to terminate the incoming signal (block 709 ). This results in minimal noise and signal reflection on the communication line coupled to the input pad.
In one embodiment, the programmable on die termination circuit reduces noise and signal reflection quickly enough and thoroughly enough to allow the communication line to improve its transfer rate. In one embodiment the communication line communicating with a device with a programmable on die termination circuit may be capable of 400 megatransfers per second (MTS). In one embodiment, the communication channel may be a double data rate (DDR) memory bus, or similar communication line.
In one embodiment, the on die termination circuit may be used by memory controller chipsets or any circuit communicating on a bus or similar communication line. In one embodiment, programmable on die termination circuits may provide consistent programmable target impedance throughout a PVT range by providing flexibility in settings via the multiplier and offset components of the conversion circuit. The on die termination scheme may conserve space on and decrease cost of main boards and similar platforms. The on die termination scheme also allows the same devices to be used in different environments and systems due to their programmable termination settings.
The system for programmable on die termination may be implemented in software, for example, in a simulator, emulator or similar software. A software implementation may include a microcode implementation. A software implementation may be stored on a machine readable medium. A “machine readable” medium may include any medium that can store or transfer information. Examples of a machine readable medium include a ROM, a floppy diskette, a CD-ROM, an optical disk, a hard disk, a radio frequency (RF) link, and similar media and mediums.
In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes can be made thereto without departing from the broader spirit and scope of the embodiments of the invention as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. | Embodiments include an on die termination circuit. The on die termination circuit may be programmable. The on die termination circuit may be programmed to compensate for environmental conditions and the physical characteristics of the device. The programmed on die termination circuit allows for faster transfer rates over communication lines by reducing the time needed to recover from signal reflection and similar issues. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to the construction of a shoe and, more particularly, to a midsole construction with improved comfort and shock absorption to enhance the comfort of a user's foot.
[0002] The footwear industry has seen numerous design features introduced over the years in order to enhance the comfort, cushioning, resiliency and shock absorption capabilities of a shoe. Many of the technological advances have occurred in the sole, particularly the midsole. In most footwear, the midsole often provides both protective cushioning and shock absorption for the user's foot. In an effort to provide improved performance, it is often desirable to vary the support characteristics of the sole from one region to another. A wide variety of soles have been developed to provide variable support for the foot. These advances include using air cushioning systems such as air cavities or air bladders disposed within the sole of a shoe Although a marked improvement over conventional uniform sole constructions has occurred over the years, there still remains a need for a midsole construction that can be adapted to provide additional comfort and shock absorption to the wearer's foot.
[0003] It would therefore be desirable to provide an improved midsole construction which is capable of providing increased comfort and shock absorption for the foot without using air cavities and/or air bladders to achieve the same.
SUMMARY OF THE INVENTION
[0004] A shoe is generally composed of an upper connected to a sole. The sole of a shoe is generally comprised of an outsole, a midsole, an insole, and on occasion, a sock liner. The present invention is directed to an improved midsole construction having multiple layers of varying materials, each layer of material having a different hardness/softness level.
[0005] In one aspect of the present invention, a midsole is provided which includes a three-layered construction, namely, a top layer, a middle layer and a bottom layer. The top layer provides a layer of material between the insole of the shoe and the second or middle layer of the midsole; the middle layer provides cushioning to the foot; and the bottom layer provides additional cushioning and a contacting surface for the outsole. In one embodiment, the top layer is made of a polyurethane material with a hardness in the range of 60-90° Asker C hardness, the middle layer is made of a thermoplastic rubber material with a hardness in the range of 20-65° Asker C hardness, and the bottom layer is made of a polyurethane material with a hardness in the range of 20-50° Asker C hardness. In one embodiment, the middle layer spans the heel portion of the shoe only and includes an upper surface which mates with and attaches to a portion of the bottom surface of the top layer and a bottom surface which mates with and attaches to a portion of the upper surface of the bottom layer. As a result, in the forefront area of the shoe, the bottom surface of the top layer mates with and attaches directly to the upper surface of the bottom layer. The bottom layer provides a layer of material between the outsole of the shoe and the second or middle layer of the midsole in the heel portion of the shoe and a layer of material between the outsole of the shoe and the top layer of the midsole in the forefront portion of the shoe. The three layers of the midsole have varying hardness/softness levels with the top layer being harder than the middle and bottom layers and with the middle layer being harder than the bottom layer. These layers can be attached to each other by any suitable means such as cement adhesion and/or stitching.
[0006] In another embodiment, the three layers of material forming the midsole are re-arranged such that the top layer is harder than the middle and bottom layers but the middle layer is softer than the bottom layer. In one embodiment, the bottom layer has an upper surface which mates with and attaches to only a portion of the bottom of the middle midsole layer and the bottom surface thereof mates with and attaches to a portion of the upper surface of the outsole in the heel portion of the shoe. In this particular embodiment, the middle layer of the midsole attaches directly to the upper surface of the outsole in the forefront portion of the shoe.
[0007] It is an object of the present invention to provide a midsole which provides enhanced comfort and shock absorption by utilizing multiple layers of varying materials which are likewise of varying hardness/softness levels.
[0008] Specific advantages and features of the present midsole construction will be apparent from the accompanying drawings and the description of the several embodiments of the present invention.
DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of one embodiment of a shoe constructed in accordance with the teachings of the present invention.
[0010] FIG. 2 is an exploded view of the shoe of FIG. 1 showing construction of the midsole.
[0011] FIG. 3 is an exploded view of the embodiment of the midsole shown in FIG. 2 .
[0012] FIG. 4 is an exploded view of another embodiment of the midsole of the shoe shown in FIG. 1 .
[0013] FIG. 5 is an exploded view of the embodiment of the midsole shown in FIG. 4 .
[0014] FIG. 6 is a rear elevational view of the bottom layer of the midsole embodiment shown in FIGS. 4 and 5 .
[0015] It should be understood that the drawings are not necessarily to scale and that the embodiments disclosed herein are sometimes illustrated by fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted. It should also be understood that the invention is not necessarily limited to the particular embodiments illustrated herein. Like numbers utilized throughout the various figures designate like or similar parts or structure.
DETAILED DESCRIPTION
[0016] A shoe generally includes an upper and a sole assembly that is affixed to the upper. The sole assembly generally includes an insole, a midsole, and an outsole, each having a peripheral shape designed to conform to the shape of a wearer's foot. To facilitate disclosure of the present invention, reference will be made to various general areas of the foot, such as the heel, arch and forefoot areas. When used to refer to locations on the various sole components, these terms should be interpreted to include those areas of the midsole and outsole that are disposed generally (and not necessarily directly) beneath the corresponding elements of the foot. It should be understood, however, that the boundaries between the heel, arch and forefoot areas are not precise and that these terms should be interpreted loosely and with a great deal of flexibility.
[0017] Referring now to the drawings and, in particular, FIGS. 1-3 , a first embodiment of a new and improved shoe midsole construction having multiple layers embodying the principles and concepts of the present invention and generally designated by the reference numeral 20 in FIGS. 2 and 3 will be described.
[0018] A shoe 12 ( FIG. 1 ) generally includes an upper 14 and a sole assembly 16 that is affixed to the upper 14 . Sole assembly 16 typically includes an insole 18 , a midsole 20 , and an outsole 22 and is attached to the upper 14 using a conventional method of attachment such as an adhesive, stitching or injection molding. In the embodiment illustrated in FIG. 1 , the insole 18 is formed as part of the upper 14 . The midsole 20 includes three layers, a top layer 24 , a middle layer 26 and a bottom layer 28 . The midsole 20 , as shown in FIGS. 2 and 3 , has an upper surface 30 and a bottom surface 32 . The top layer 24 of the midsole 20 can be attached via conventional means to either an insole such as insole 18 , or to the upper 14 , while the bottom surface 32 of bottom layer 28 is attached to the outsole 22 using a conventional method of attachment.
[0019] Top layer 24 of the midsole 20 is positioned below the insole 18 and above the middle layer 26 of the midsole 20 . The specific material of the top layer 24 may be chosen depending upon the nature and type of shoe in which it will be used. Top layer 24 may be made from a variety of materials including, but not limited to, molded Polyurethane (PU), Polyvinyl Chloride (PVC), Thermoplastic Urethane (TPU), Thermoplastic Rubber (TPR), vulcanized rubber, ethyl vinyl acetate (EVA), rubberlon, or any other synthetic or natural material. The material forming the top layer 24 has a hardness factor greater than the middle and bottom layers 26 and 28 and is generally in the range of 60-90° Asker C hardness. The material and hardness/softness ranges selected will be determined by the type of footwear onto which midsole 20 is intended to be placed.
[0020] Lying underneath top layer 24 of the midsole 20 is a middle layer 26 having an upper surface 36 and a bottom surface 40 . In the embodiment illustrated in FIGS. 2 and 3 , the middle layer 26 only extends across the heel portion of top layer 24 and bottom layer 28 and may be made from a variety of materials including, but not limited to, TPR. The upper surface 36 of middle layer 26 is attached to the bottom surface 34 of the top layer 24 at the heel portion of the sole 16 using a conventional method of attachment, such as adhesive, while the bottom surface 40 of the middle layer 26 is attached to the upper surface 38 of the bottom layer 28 in the heel portion of the sole 16 . In contrast, the bottom surface 34 of the top layer 24 is attached directly to the upper surface 38 of bottom layer 28 in the arch and forefoot areas of the sole 16 . The middle layer 26 may further be secured to the top layer 24 by utilizing male connection portions, projections or components 42 associated with the bottom surface 34 of the top layer 24 which portions 42 mate with and engage corresponding female connection portions, openings or components 44 associated with the middle layer 26 as best shown in FIG. 3 . Regardless of the type of material used for the middle layer 26 , the middle layer 26 is softer than the top layer 24 and is generally of a hardness in the range of 20-65° Asker C hardness, and preferably in the range of 40-60° Asker C hardness.
[0021] The bottom layer 28 of the present midsole 20 is positioned below the middle layer 26 in the heel area of the sole 16 and below the top layer 24 in the arch and forefront areas of the sole 16 and above the outsole 22 . The specific material of the bottom layer 28 may again be chosen depending upon the nature and type of shoe in which it will be used. The bottom layer 28 may be made from a variety of materials including, but not limited to, molded Polyurethane (PU), Polyvinyl Chloride (PVC), Thermoplastic Urethane (TPU), Thermoplastic Rubber (TPR), vulcanized rubber, EVA, rubberlon, or any other synthetic or natural material. The material forming the bottom layer 28 has a hardness factor which is softer than both the top layer 24 and the middle layer 26 and is generally in the range of a 20-50° Asker C hardness, and preferably in the range of 20-40° Asker C hardness. The material and hardness/softness ranges selected will again be determined by the type of footwear onto which midsole 20 is intended to be placed. The upper surface 38 of the bottom layer 28 of the midsole 20 is attached to the bottom surface 40 of the middle layer 26 of the midsole 20 in the heel portion of the sole 16 using a conventional method of attachment, while the upper surface 38 of the bottom layer 28 of the midsole 20 in the arch and forefront areas of the shoe 16 is attached directly to the bottom surface 34 of the top layer 24 of the midsole likewise using conventional means.
[0022] In the particular embodiment illustrated in FIGS. 2 and 3 , the middle layer 26 of midsole 20 is utilized to provide additional comfort to the wearer of the shoe 12 in that the middle layer 26 acts as a cushioning means to further cushion the heel of the wearer as the heel portion of the shoe 12 strikes the ground during a normal gait. In some embodiments, the middle layer 26 may be comprised of a gel type material which provides increased shock absorption and energy return whereas the top and bottom layers 24 and 28 of the midsole 20 can be made of a dual density lightweight material which likewise provide support and shock absorption. It is also recognized and anticipated that in some embodiments, the middle layer 26 of the midsole 20 may extend beyond the heel portion of the sole 16 to include the arch area and/or forefoot area of the sole 16 as well, or portions thereof. Regardless of the types of materials used for each of the three separate layers 24 , 26 and 28 associated with the present midsole construction 20 , improved comfort and cushioning is achieved in this particular midsole construction due to the fact that the top layer 24 of the midsole 20 is harder than the middle layer 26 of the midsole 20 , which, in turn, is harder than the bottom layer 28 of the midsole 20 . Stated another way, the bottom layer 28 is softer than the middle layer 26 which, in turn, is softer than the top layer 24 of the midsole construction 20 . This arrangement of layers and hardness factors provides for improved comfort and cushioning to the wearer of the shoe 12 .
[0023] In another embodiment, referring now to the drawings and, in particular, FIGS. 4-6 , a second embodiment of a new and improved shoe midsole construction having multiple layers embodying the principles and concepts of the present invention and generally designated by the reference numeral 46 in FIGS. 4 and 5 will be described.
[0024] In the embodiment illustrated in FIG. 4 , the insole 18 is again formed as part of the upper 14 . The midsole 46 includes three layers, a top layer 48 , a middle layer 50 and a bottom layer 52 . The midsole 46 , as shown in FIGS. 4-6 , has an upper surface 54 and a bottom surface 56 . The top layer 48 of the midsole 46 can be attached via conventional means to either an insole such as insole 18 , or to the upper 14 , while the bottom surface 56 of bottom layer 52 is attached to the outsole 22 using a conventional method of attachment.
[0025] Top layer 48 of the midsole 46 is positioned below the insole 18 and above the middle layer 50 of the midsole 46 . The specific material of the top layer 48 may be chosen depending upon the nature and type of shoe in which it will be used. Top layer 48 may be made from a variety of materials including, but not limited to, molded Polyurethane (PU), Polyvinyl Chloride (PVC), Thermoplastic Urethane (TPU), Thermoplastic Rubber (TPR), vulcanized rubber, EVA, rubberlon, or any other synthetic or natural material. The material forming the top layer 48 has a hardness factor greater than the middle and bottom layers 50 and 52 and is generally in the range of 60-90° Asker C hardness. The material and hardness/softness ranges selected will be determined by the type of footwear onto which midsole 46 is intended to be placed.
[0026] Lying underneath top layer 48 of the midsole 46 is a middle layer 50 having an upper surface 58 and a bottom surface 60 . Middle layer 50 of the midsole 46 is positioned below the top layer 48 and above the bottom layer 52 of the midsole 46 . The specific material of the middle layer 50 may be chosen depending upon the nature and type of shoe in which it will be used. Middle layer 50 may be made from a variety of materials including, but not limited to, molded Polyurethane (PU), Polyvinyl Chloride (PVC), Thermoplastic Urethane (TPU), Thermoplastic Rubber (TPR), vulcanized rubber, EVA, rubberlon, or any other synthetic or natural material. The material forming the middle layer 50 has a hardness factor lesser than the top and bottom layers 48 and 52 and is generally in the range of 20-50° Asker C hardness, and preferably in the range of 20-40° Asker C hardness. The material and hardness/softness ranges selected will be determined by the type of footwear onto which midsole 46 is intended to be placed.
[0027] In the embodiment illustrated in FIGS. 4 and 5 , the middle layer 50 extends across the entire length of the top layer 48 . The upper surface 58 of middle layer 50 is attached to the bottom surface 62 of the top layer 48 using a conventional method of attachment, such as adhesive, while the bottom surface 60 of the middle layer 50 is attached to the upper surface 64 of the bottom layer 52 in the heel portion of the sole 16 and to the upper surface 66 of the outsole 22 in its remaining portion, namely, in the arch and forefoot areas.
[0028] The bottom layer 52 of the present midsole 46 is positioned below the middle layer 50 and above the outsole 22 and may be made from a variety of materials including, but not limited to, TPR. The upper surface 64 of bottom layer 52 is attached to the bottom surface 60 of the middle layer 50 at the heel portion of the sole 16 using a conventional method of attachment, such as adhesive, while the bottom surface 56 of the bottom layer 52 is attached to the upper surface 66 of the outsole 22 in the heel portion of the sole 16 . In contrast, the bottom surface 60 of the middle layer 50 is attached directly to the upper surface 66 of the outsole 22 in the arch and forefoot areas of the sole 16 . The bottom layer 52 may further be secured to the middle layer 50 by utilizing male connection portions, projections, flanges or components 68 associated with the top surface 64 of the bottom layer 52 as best shown in FIG. 6 , which portions 68 mate with and engage corresponding female connection portions, cut-outs, cavities, notches or components 70 associated with the middle layer 50 as best shown in FIGS. 4 and 5 . The flanges 68 mate with and engage the cut-outs 70 when the bottom layer 52 is attached to the middle layer 58 . Regardless of the type of material used for the bottom layer 52 , the bottom layer 52 is softer than the top layer 48 and is generally of a hardness in the range of 20-65° Asker C hardness, and preferably in the range of 40-60° Asker C hardness.
[0029] In the particular embodiment illustrated in FIGS. 4 , 5 and 6 , the bottom layer 52 of midsole 46 is utilized to provide additional shock absorption to the wearer of the shoe 12 in that the bottom layer 52 acts as a shock absorption means to further absorb shock to the heel of the wearer as the heel portion of the shoe 12 strikes the ground during a normal gait. It is also recognized and anticipated that in some embodiments, the bottom layer 52 of the midsole 46 may extend beyond the heel portion of the sole 16 to include the arch area and/or forefoot area of the sole 16 as well, or portions thereof. Regardless of the types of materials used for each of the three separate layers 48 , 50 and 52 associated with the present midsole construction 46 , improved shock absorption is achieved in this particular midsole construction due to the fact that the top layer 48 of the midsole 46 is harder than the middle layer 50 and bottom layer 52 of the midsole 46 and the bottom layer 52 is harder than the middle layer 50 of the midsole 56 . Stated another way, the bottom layer 52 is softer than the top layer 48 , but is harder than the middle layer 50 of the midsole construction 46 . This arrangement of layers and hardness factors provides for improved shock absorption to the wearer of the shoe 12 .
[0030] Thus, there have been shown and described two embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | A midsole adapted for attachment to a shoe having multiple layers of varying materials each having a different hardness level. More particularly, the present midsole includes a top, middle and bottom layer wherein all three layers of material have a different hardness range and wherein at least one of the layers is made from thermoplastic rubber (TPR). In one embodiment, the thermoplastic rubber (TPR) layer lies between the top and bottom layers and in another embodiment, the thermoplastic rubber (TPR) layer is the bottom layer. The thermoplastic rubber (TPR) layer may also have a length shorter than the other two layers forming the midsole. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. §119(e) of provisional application 60/198,021 filed on Apr. 18, 2000, currently pending.
FIELD OF THE INVENTION
[0002] This invention relates to a border for a computer screen in general, and more particularly to a border having an appearance that is variable and customizable and capable of receiving personalized images inserted therein.
BACKGROUND OF THE INVENTION
[0003] In a day where everything seems to be personalized and almost everyone owns a display monitor of some sort, it seems impossible to offer a display monitor that can suit the tastes of each individual. For instance, most monitors are provided in a single color, usually black, gray, white or some other neutral color. While such a color scheme may be compatible with most surroundings, it is boring to look at. Thus, considering that most people spend their work lives in front of a computer screen, there is a need for a computer screen that is attractive, interesting in appearance and appealing to behold.
[0004] The apparatus of the present invention addresses such need, and enables users to customize their display monitors to fit their personal tastes, decor, or just the way they feel. The present invention allows a person to change the look of their monitor as their tastes change, and consists of a series of display chambers disposed about the peripheral edge of the monitor that are adapted to receive customized display items. A countless variety of images or objects from various sources may be inserted into such chambers to achieve a desired look. Images may include everything from baby photos to vacation pictures, themes to fit certain occasions and holidays, or photos and logos of a favorite sports team. Everything from personal creations, magazine clippings, to images downloaded from the Internet may be displayed in such display chambers to enhance and customize the appearance of a monitor.
DESCRIPTION OF THE PRIOR ART
[0005] In the past, similar devices have been proposed to alter the appearance or offer a useful element to a display monitor. Such devices are usually fixed or otherwise secured to the display monitor in some fashion. Unlike the prior art, however, the screen border of the present invention, once secured to the monitor, may be temporarily displaced to provide the user with access to control buttons positioned on the front of the monitor housing.
[0006] In a preferred embodiment, the screen border of the invention is hingedly connected to the monitor, such that it may be pivoted from a position adjacent or against the monitor display screen to a position away from the monitor. Usually, the hinges are positioned on the top of the screen border and monitor, such that the border may be pivoted upwardly toward the user and away from the screen. Alternatively, the hinges may be positioned on the side of the screen border and monitor, such that the border may be pivoted to the side away from the screen. Thus, when it is desired to adjust the monitor settings or turn the power on or off, the border of the invention may be temporarily displaced without having to painstakingly remove the entire unit from the monitor housing.
[0007] The prior art is also limited to devices consisting of removable and interchangeable display components and does not offer the ability to insert and change images without the use of some means to attach or affix the images to the device. The computer screen border of the present invention provides a user with the ability to manipulate and interchange images and objects as many times as desired.
[0008] For instance, U.S. Pat. No. 4,869,565 discloses a display apparatus which is affixed to the sides and top of a computer monitor. Channel members are provided along the sides and top to hold large “L” shaped display members. Images are then attached to the display members, not inserted into the channels themselves.
[0009] U.S. Pat. No. 5,104,087 discloses a note/memo board designed to surround a computer display housing on only three sides. The board attaches to the display housing with the use of angle brackets backed with VELCRO® material with matching strips on the sides and top of the device . The note/memo board, however, mounts to the back of the computer screen, not on the actual face, which positions the screen beyond the user's field of focus.
[0010] U.S. Pat. No. 5,398,905 discloses a die-cut display board for a computer video monitor wherein a cardboard, plastic, or foam back is secured to the computer video monitor by means of double-stick tape or a VELCRO® material. The middle region, where the screen would appear, is scored such that the middle may be pushed apart creating tabs to be folded in towards the rear of the device to lie on the top and the sides of the monitor to form an opening to view the screen.
[0011] U.S. Pat. No. 5,549,267 discloses a frame assembly that adheres to the face of a computer monitor by means of a repositionable pressure sensitive adhesive. The front surface of the frame is adapted to have sheets of paper and other objects releasably adhered thereto. The frame assembly may also include different sized central cut outs to fit devices having different sized view able surfaces.
[0012] U.S. Pat. No. 5,564,209 discloses an apparatus for positioning around a screen comprising, a strap of a flexible material with a circumference that allows it to be positioned around the upper surface, lower surface and side surfaces of the screen that assumes a rectangular configuration when placed therearound. A decorative attachment, in the form of a doll, sports event scene, beach scene or the like, may than be supported by the strap.
[0013] U.S. Pat. No. 5,638,096 discloses a display frame specifically for computer monitors. The display frame is adhesively affixed to the front surface of a monitor. In order to change the decorative image of the frame, the user must replace the frame with a frame having a different image. The frame also does not allow easy access to control buttons that may exist on a monitor housing. Such frame may also consist of a plurality of slots in which the corners only of photographs are placed.
[0014] U.S. Pat. No. 5,678,792 discloses a display device and method of attaching objects such as pictures, notes and the like to appliances. Such device consists of a substantially flexible, lengthwise deformable band that is extended around the perimeter of an appliance. Objects are secured in. place by the deformable material creating frictionous contact with the appliance. U.S. Pat. No. 5,890,603 discloses a similar display device.
[0015] U.S. Pat. No. 5,197,213 discloses a decorative frame having a plurality of enclosure members for retaining appearance-altering material. The enclosure members are adhesively connected to each other and the frame backing, such that the appearance-altering material cannot be repeatedly changed at will. A main objective of the '213 device is to permit the changing of a picture or mat which surrounds the picture without simultaneously affecting the appearance-altering material disposed within the enclosure members.
[0016] U.S. Pat. No. 5,465,514 discloses a readily variably decorative self-standing picture frame. This picture frame consists of recessed sides and end walls which are sufficient to receive a glass plate, a suitable illustration, and a protective backing layer having a pedestal to support the frame in an upward position. The '514 frame also includes a number of stud members placed on the rear of the back layer for securing the frame to a back wall. Disposed in the recessed walls are transparent cylindrical tubes adapted to receive therein varied changeable decorative enclosures. The length of such cylindrical tubes extend into portions of corner recesses, which are adapted to receive and secure retainers. These retainers overlap the ends of the cylindrical tubes therefore holding the tubes securely in place. In order to change a decorative enclosure, such tubes must be removed entirely from the frame.
[0017] U.S. Pat. No. 2,593,195 discloses a backing board for picture frames having a plurality of metal strips adjustable thereacross. Each of the metal strips consist of prongs near the ends allowing a piercing engagement with the backing board, which allows pictures of different sizes to be secured in different positions against the backing board.
[0018] U.S. Pat. No. 5,672,105 discloses a monitor mask utilizing a plurality of pages which partially surround a computer screen. The pages are bound such that they may be individually moved.
OBJECTS OF THE INVENTION
[0019] It is an object of the present invention, therefore, to provide a bordering area for a screen that can be customized in appearance.
[0020] It is a further object of the present invention to provide a screen border having chambers for the receipt and display of image-bearing material.
[0021] It is a further object of the present invention to provide a bordering area that allows for quick and easy insertion and exchange of image-bearing material within such chambers.
[0022] It is a further object of the present invention to provide a screen border that is hingedly attached to a screen, allowing the border to be pivoted away from the screen to gain access to control buttons or the like without necessitating the removal of the border from the screen to accomplish the same task.
[0023] Still other objects and advantages of the invention will become clear upon review of the following detailed description in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
[0024] The computer screen border of the present invention comprises a plurality of chambers that are adapted to receive appearance-changing objects therein. Such objects may be image-bearing strips or decorative, three-dimensional objects. The chambers are positioned around the perimeter and are secured to the screen border, with the interior of such chambers being easily accessible such that the image-bearing strips or objects may be inserted into and removed therefrom without necessitating removal of the chambers or the border from the screen. The border of the invention may be integrally formed into a monitor housing, or it may be removably or permanently attached to an existing monitor housing. A hinged connection may be incorporated into the construction of the border so that the border may be temporarily pivoted away from the computer screen to allow a user to gain access to controls or the like positioned behind the border.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] [0025]FIG. 1 is a perspective view of a screen border of the present invention.
[0026] [0026]FIG. 2 is a side view of FIG. 1.
[0027] [0027]FIG. 3 is a perspective view of the border of FIG. 1 showing the removal of the corners pieces of the border of the invention.
[0028] [0028]FIG. 4A illustrates the insertion of images into the receiving chambers of the present invention and FIG. 4B illustrates a border of the invention having images positioned within the receiving chambers.
[0029] [0029]FIG. 5 is a perspective view of one embodiment of a screen border of the invention hingedly connected to a monitor.
[0030] [0030]FIG. 6 is a side view of the border of FIG. 5 showing the pivoting movement of the border with respect to the monitor.
[0031] [0031]FIG. 7 is a perspective view of another embodiment of a border of the present invention, wherein a continuous screen border is hingedly connected to a base member that has been attached to or integrally formed into a monitor.
[0032] [0032]FIG. 8 is a side view of the border of FIG. 7 showing the pivoting movement of the continuous border with respect to the monitor.
[0033] [0033]FIG. 9 is a detailed perspective view showing the insertion of an image-bearing insert in accordance with the embodiment of FIGS. 7 and 8.
[0034] [0034]FIG. 10 is a perspective view of another embodiment of a border of the present invention, wherein a continuous screen border is completely removable from the monitor and snap fit or otherwise engageable with the monitor.
[0035] [0035]FIG. 11 is a side view of the border of FIG. 10 showing the engagement of the continuous border with respect to the monitor.
[0036] [0036]FIG. 12 is a perspective view of another embodiment of a border of the present invention, wherein the receiving chambers are completely removable in order to gain access to and insert and/or image-bearing inserts.
[0037] [0037]FIG. 13 a detailed perspective view showing the insertion of an image-bearing insert in accordance with the embodiment of FIG. 12.
[0038] [0038]FIG. 14 is a perspective view of another embodiment of a border of the present invention, wherein the receiving chambers are separately hingedly attached to the border.
[0039] [0039]FIG. 15 is a detailed perspective view showing the insertion of an image-bearing insert in accordance with the embodiment of FIG. 14.
[0040] [0040]FIG. 16 is a perspective view of another embodiment of a border of the present invention utilizing slots along the base member and/or receiving chambers in order to gain access to insert and change image-bearing inserts.
[0041] [0041]FIG. 17 is a detailed perspective view showing the insertion of an image-bearing insert through a slot in accordance with the embodiment of FIG. 16.
[0042] [0042]FIG. 18 is a perspective view of another embodiment of the border of the invention, wherein a the border is slidably attached to the monitor.
[0043] [0043]FIG. 19 is a side view of another embodiment of the border of the invention, wherein the border is mountable to a monitor as a separate unit by a hook-like clamp or bracket.
[0044] [0044]FIG. 20 illustrates the pivotal movement of the border of FIG. 19 about the top of the monitor, the border being mountable to a monitor by a clamp-like bracket.
[0045] [0045]FIG. 21 is a side view of another embodiment of the border of the invention, wherein the border is mountable to a full-sized monitor by a flat bracket.
[0046] [0046]FIG. 22 illustrates the pivotal movement of the border of FIG. 21 about the top of the monitor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] The following detailed description is of the best mode or modes of the invention presently contemplated. Such description is not intended to be understood in a limiting sense, but to be an example of the invention presented solely for illustration thereof, and by reference to which in connection with the following description and the accompanying drawings one skilled in the art may be advised of the advantages and construction of the invention. In the various views of the drawings, like reference characters designate like or similar parts.
[0048] [0048]FIG. 1 is a three-dimensional view and FIG. 2 is a side view of the screen border 5 of the present invention shown attached to a monitor 10 having a screen 11 . While a flat-panel monitor housing 10 is shown in the appended drawings, the border of the invention 5 will be usable with other monitor types as well (see, for example, FIGS. 21 and 22). The border 5 preferably comprises a plurality of cover members 20 positioned around the perimeter of a base member 12 , such members 20 being adapted to display image-bearing elements 16 as discussed below and defining a central opening in said base member 12 through which the monitor screen 11 is viewable. Outwardly projecting side walls 13 (see also FIGS. 9, 13, 15 , etc.) extending from the base member 12 and positioned along the longitudinal edges of the cover members 20 define a receiving chamber between the members 20 and the base member 12 , such receiving chamber being adapted to accommodate image-bearing elements therein as will be described below. Corner pieces 14 preferably having colored attachments 15 are disposed along the corners of the base member 12 , such that the corner pieces 14 in combination with the cover members 20 define a continuously-appearing border around said base member 12 . While such corner pieces 14 are described with attachments 15 , such attachments are not necessary for the operation of the border of the invention. The corner pieces 14 are removable from the border 5 (FIG. 3) and preferably reattachable thereto by a friction fit connection between the corner pieces 14 and either the base member 12 or the receiving chambers. However, other methods of connection between the corner pieces 14 and the border 5 , such as a tongue and groove, male/female, adhesive, Velcro® connection or the like, may be used.
[0049] The cover members 20 are preferably affixed to the base member 12 between the side walls 13 , such that the receiving chambers are dimensioned to receive and display image-bearing inserts 16 therein (FIGS. 4A and 4B). In this regard, cover members 20 are preferably formed from a hollow, transparent or translucent material so that the image-bearing inserts 16 are clearly viewable through said members 20 (FIG. 4B). The inserts 16 preferably have the same longitudinal dimension (length) as the members 20 , and the corner pieces 14 preferably act as barriers, so that the inserts 16 are bounded by the cover members 20 and the corner pieces 14 when the corner pieces 14 are attached to the border 4 . Furthermore, there preferably exists a slight gap between the edges of the cover members 20 , the side walls 13 and the base member 12 for accommodating the image-bearing inserts (see, for example, FIGS. 15 and 17). However, such slight gap does not have to be present, and the receiving chambers can instead be defined between the cover members 20 and the base member 12 .
[0050] [0050]FIG. 4A illustrates a plurality of inserts 16 a - 16 d (collectively defined by the reference number 16 ), a plurality of corner pieces 14 a - 14 d (collectively defined by the reference number 14 ), a plurality of attachments 15 a - 15 d (collectively defined by the reference number 15 ) and a plurality of cover members 20 a - 20 d (collectively defined by the reference number 20 ). With the corner pieces 14 removed from the border 5 , the inserts 16 may be added to the receiving chambers as follows, it being understood that such process is only illustrative of one potential process for creating the border of the invention. First, corner piece 14 a is attached to the border 5 so that insert 16 a can be inserted into the receiving chamber defined by cover member 20 a in the direction of the arrow as shown. Corner piece 14 a acts as a stop, preventing the overinsertion of insert 16 a through the receiving chamber. Once insert 16 a has been fully inserted, corner piece 14 d is attached to the border 5 , thereby completing the lower edge of the border 5 . With the corner pieces 14 a and 14 d in place, inserts 16 b and 16 c may be dropped into receiving chambers defined by cover members 20 b and 20 d , such that corner pieces 14 a and 14 d act as stops preventing such inserts 16 b and 16 c from falling completely through such chambers. Once inserts 16 a - 1 6 c are in place, corner piece 14 b is attached to the border 5 and insert 16 d is advanced through the receiving chamber defined by cover member 20 c until it impacts corner piece 14 b . Finally, corner piece 14 c is attached to complete the border 5 (FIG. 4B).
[0051] All of the attachments 15 a - 15 d provided on the corner pieces 14 a - 14 d may be the same in appearance, or each may be different as the case may be, it being understood that the attachments 15 provide yet a further means for varying the overall appearance of the border 5 . Such attachments 15 may also be colored, solid, striped, have a design that matches the design of the inserts 16 , or the like. Also, each of the inserts 16 a - 16 d may have a different design, image or the like, or all of the inserts 16 may have the same design, image, appearance or the like, depending on the desires of the user. Furthermore, the cover members 20 , while preferably transparent or translucent, may also be adorned with designs, embossings, engravings or the like (not specifically shown). Thus, the overall design of the border 5 of the invention provided by the combination of the corner pieces 15 , cover members 20 and inserts 16 may be varied and customized according to the desires of the user.
[0052] The general concept of the screen border 5 of the present invention has been described in connection with FIGS. 1 - 4 B. However, there are a variety of ways such border 5 can be operated and applied to a computer screen 10 or the like.
[0053] In one embodiment as shown in FIGS. 5 and 6, the border 5 of the present invention can be integrally connected to the monitor by a hinge connection 17 or the like, which allows the border 5 to be pivoted away from the screen 11 to provide access to control buttons 27 or the like situated on the monitor housing. Such hinge connection 17 may be configured with a hold position to retain the border 5 in a pivoted position as shown in FIG. 6 without requiring that the user constantly support the border 5 . The border 5 may be pivoted outward only slightly, or to a position that is substantially perpendicular to said screen. Or, such hinge connection 17 may require that the user support the border 5 at all times during pivoting. In the embodiment of FIGS. 5 and 6, the border 5 will be in a rest position directly adjacent the computer monitor 10 (see FIG. 1 for example).
[0054] FIGS. 7 - 9 illustrate another embodiment of the border of the present invention, wherein the base member 12 is attached to the monitor 10 , and the cover members and corner pieces are connected to form a continuous member 19 that is hingedly attached to the base member 12 . As shown in FIG. 9, the combination of the side walls 13 and the base member 12 create a cavity along the base member 12 for receipt of the inserts 16 , which cavity is then enclosed by the continuous display member 19 when such member 19 is pivoted into a position adjacent the monitor 10 .
[0055] FIGS. 10 - 11 illustrate another embodiment of the border of the present invention, wherein the base member 12 is attached to the monitor 10 , and the cover members and corner pieces are connected to form a continuous member 19 that is snapped to or otherwise completely removable from, and engageable with, the base member 12 . Inserts 16 are added to the border of FIGS. 10 - 11 as illustrated in FIG. 9. In the embodiments illustrated in FIGS. 7 - 11 , decorative attachments 15 may be added to the continuous display member 19 as desired.
[0056] As noted above with respect to the embodiment of FIGS. 1 - 4 B, it is preferred if the cover members 20 are secured or fixed to the base member 12 . However, such members 20 may be completely removable from the base member 12 as shown in FIGS. 12 - 13 , or separately hingedly connected to the base member 12 as shown in FIGS. 14 - 15 . In the embodiment of FIG. 12, for example, each of the members 20 are completely removable from the base member 12 by means of a snap fit engagement or the like. Thus, as shown in FIG. 13, an image-bearing insert 16 is inserted into the receiving chamber defined between the base member 12 and side walls 13 after the cover member 20 is disengaged from the base member 12 . In the embodiment of FIG. 14, for example, each of the receiving chamber sections, defined by a cover member 20 , base member section 12 and side wall sections 13 , is hingedly attached to the monitor 10 by means of a hinge 10 . Thus, as shown in FIG. 15, an image-bearing insert 16 is inserted into the receiving chamber defined between the cover member 20 , base member 12 and side walls 13 . Preferably, an image-bearing insert 16 is inserted into a slight opening or gap defined between the ends of the cover member 20 , the base member 12 and side walls 13 as discussed above and as shown (see also FIG. 17).
[0057] FIGS. 16 - 17 illustrate another embodiment of the present invention, wherein the base member 12 comprises openings or slots 21 along the outer peripheral edges to accommodate the passage of image-bearing inserts 16 therethrough. The lowermost cover member 20 might also have a slot 21 along its upper peripheral surface as shown in FIG. 16. Such inserts 16 should be dimensioned to extend partially outside said slots 21 when fully inserted within the receiving chambers so that said inserts 16 may be gripped and changed as desired.
[0058] [0058]FIG. 18 illustrates yet another embodiment of the present invention, wherein the continuous member 19 further comprises an extending lip 23 on both the top and bottom peripheral edges as shown, which lips 23 ride inside a longitudinal channel 22 formed in the upper and lower peripheral edges of the base member 12 . Thus, the continuous member 19 can move from side to side as shown without having to remove the entire member 19 to gain access to insert images 16 .
[0059] FIGS. 19 - 22 illustrate yet another embodiment of the present invention, wherein the border 5 is formed as a separate unit from the monitor 5 and is separately and preferably removably attachable thereto. In FIGS. 19 and 20, the border 5 is supported on the flat screen monitor 10 by a hook-like or clamp-like bracket 24 to which the border is pivotally connected by a hinge 17 . The bracket 24 may be temporarily adhesively attached to the monitor 10 or it may merely grip the monitor 10 as shown. In FIGS. 21 and 22, a flat bracket 25 is connected to the full-sized monitor 10 by a suitable attachment 25 and pivotally connected to the border 5 by a hinge 17 . The semi-permanent attachment means 25 may be some type of adhesive material, Velcro® strips or the like. Other attachment means, such as by a snap connection or the like, are also contemplated.
[0060] While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. | A screen border has a plurality of chambers that are arranged around the perimeter of the border. The chambers are adapted to receive appearance-changing objects, such as image-bearing strips or decorative, three-dimensional objects, therein. Appearance-changing objects may be easily inserted into and withdrawn from the interior of the chambers through access areas provided on the border. The border may be integrally formed into a housing, or it may be removably or permanently attached to an existing housing. A hinged connection may be incorporated into the construction of the border so that the border may be temporarily pivoted away from the screen to allow a user to gain access to controls or the like positioned behind the border. | 6 |
RELATED APPLICATIONS
[0001] The present application is a continuation application and claims priority to U.S. patent application Ser. No. 13/588,171, filed on Aug. 17, 2012, which is incorporated herein by reference.
BACKGROUND
[0002] In the manufacture of paper products, such as facial tissues, bath tissues, napkins, wipes, paper towels, etc., it is often desired to optimize various properties of the products. For example, the products should have good bulk, a soft feel, and should have good strength. Unfortunately, however, when steps are taken to increase one property of the product, other characteristics of the product are often adversely affected.
[0003] For instance, it is very difficult to produce a high strength paper product that is also soft. In particular, strength is typically increased by the addition of certain strength or bonding agents to the product. Although the strength of the paper product is increased, various methods are often used to soften the product that can result in decreased fiber bonding. For example, chemical debonders can be utilized to reduce fiber bonding and thereby increase softness. Moreover, mechanical forces, such as creping or calendering, can also be utilized to increase softness.
[0004] However, reducing fiber bonding with a chemical debonder or through mechanical forces can adversely affect the strength of the paper product. For example, hydrogen bonds between adjacent fibers can be broken by such chemical debonders, as well as by mechanical forces of a papermaking process. Consequently, such debonding results in loosely bound fibers that extend from the surface of the tissue product. During processing and/or use, these loosely bound fibers can be freed from the tissue product, thereby creating lint, which is defined as individual airborne fibers and fiber fragments. Moreover, papermaking processes may also create zones of fibers that are poorly bound to each other but not to adjacent zones of fibers. As a result, during use, certain shear forces can liberate the weakly bound zones from the remaining fibers, thereby resulting in slough, i.e., bundles or pills on surfaces, such as skin or fabric. As such, the use of such debonders can often result in a much weaker paper product during use that exhibits substantial amounts of lint and slough.
[0005] As such, a need currently exists for a paper product that is strong, soft, and that has low lint and slough.
SUMMARY
[0006] Typically, increased basis weight, and in-turn sheet caliper, have a negative impact on creping and often causes increased slough in the finished tissue product. Despite this trend, the present disclosure surprisingly provides a high basis weight web having low slough. The novel tissue webs generally have basis weights greater than about 16 grams per square meter (gsm), while maintaining less than about 4 mg of slough. All while yielding tissue products that are both thick and soft.
[0007] Accordingly, in one aspect the present disclosure provides a creped tissue product comprising one or more plies, the tissue product having a geometric mean tensile (GMT) of less than about 1000 g/3″, a basis weight of at least about 33 gsm and a slough of less than about 4 mg.
[0008] In other aspects the disclosure provides a creped tissue web having a GMT of less than about 500 g/3″, a basis weight of at least about 16 gsm and a slough of less than about 4 mg.
[0009] In yet other aspects the disclosure provides a soft creped tissue web having a basis weight of at least about 16 gsm, a slough of less than about 4 mg and TS7 value from about 8 to 10. Preferably, soft creped tissues having low slough and TS7 value as also strong enough to withstand use, such that the geometric mean tensile is at least about 300 g/3″ and more preferably at least about 400 g/3″.
[0010] In still other aspects the present disclosure provides a multi-ply tissue product comprising two multi-layered creped tissue webs, the tissue webs having three superposed layers, an inner layer consisting essentially of softwood fibers and two outer layers consisting essentially of hardwood fibers, the inner layer being located between the two outer layers, wherein each web has a GMT of less than about 500 g/3″, a basis weight of at least about 16 gsm and a slough of less than about 4 mg.
[0011] In still other aspects the disclosure provides a high basis weight tissue web having a creping composition applied at high levels of addition. For example, tissue webs according to the present disclosure may be produced by applying a non-fibrous olefin polymer to the Yankee dryer at high addition levels, preferably greater than about 50 mg/m 2 (the add on rate of creping composition to the dryer, measured as dry mass (i.e., mg) per unit area of dryer surface (i.e., m 2 )). The resulting tissue webs have low slough, such as a slough less than about 4 mg, even at basis weights greater than about 16 gsm.
[0012] In yet other aspects the disclosure provides a process for producing a creped tissue web product comprising the steps of applying an aqueous polyolefin dispersion to a moving creping surface, wherein said aqueous polyolefin dispersion comprises at least one thermoplastic resin, water, and at least one dispersing agent, wherein said aqueous polyolefin dispersion has an average particle size in the range of from 0.05 μm to 5 μm and a pH in the range of from 7 to 11, and wherein said dispersion comprises more than 25 percent by weight of water; pressing a base sheet having a basis weight of at least about 16 gsm against the creping surface after the aqueous polyolefin dispersion has been applied, the aqueous polyolefin dispersion adhering the base sheet to the creping surface; and removing the base sheet from the creping surface, wherein the creped base sheet has a slough of less than about 4 mg and a GMT less than about 500 g/3″.
[0013] Other features and aspects of the present disclosure are discussed in greater detail below.
DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a comparison of basis weight (x-axis, grams per square meter) and slough (y-axis, mg) for various prior art and inventive tissue products.
[0015] FIG. 2 illustrates a perspective view of a test apparatus that can be used to measure slough according to the test method set forth herein;
[0016] FIG. 3 is a comparison of basis weight (x-axis, grams per square meter) and slough (y-axis, mg) for two different creping chemistries; and
[0017] FIG. 4 is a comparison of basis weight (x-axis, grams per square meter) and slough (y-axis, mg) for different add-on levels of a non-fibrous olefin creping composition.
DEFINITIONS
[0018] As used herein, the term “slough,” also referred to herein as “pilling” and “Scott pilling,” refers to the undesirable sloughing off of bits of the tissue web when rubbed and is generally measured as described in the Test Methods section below. Slough is generally reported in terms of mass, such as milligrams.
[0019] As used herein, the term “geometric mean tensile” (GMT) refers to the square root of the product of the machine direction tensile and the cross-machine direction tensile of the web, which are determined as described in the Test Methods section.
[0020] As used herein, the term “slope,” also referred to as “modulus,” refers to slope of the line resulting from plotting tensile versus stretch and is an output of the MTS TestWorks™ in the course of determining the tensile strength as described in the Test Methods section. Slope is reported in the units of grams (g) per unit of sample width (inches) and is measured as the gradient of the least-squares line fitted to the load-corrected strain points falling between a specimen-generated force of 70 to 157 grams (0.687 to 1.540 N) divided by the specimen width.
[0021] As used herein, the term “geometric mean modulus” (GMM) generally refers to the square root of the product of the machine direction and cross-machine direction slopes, and is an output of the MTS TestWorks™ in the course of determining the tensile strength as described in the Test Methods section.
[0022] As used herein, the term “tissue product” refers to products made from base webs comprising fibers and includes, bath tissues, facial tissues, paper towels, industrial wipers, foodservice wipers, napkins, medical pads, and other similar products.
[0023] As used herein, the terms “tissue web” and “tissue sheet” refer to a cellulosic web suitable for making for use as a tissue product.
[0024] As used herein, the term “caliper” is the representative thickness of a single sheet measured in accordance with TAPPI test methods T402 “Standard Conditioning and Testing Atmosphere For Paper, Board, Pulp Handsheets and Related Products” and T411 om-89 “Thickness (caliper) of Paper, Paperboard, and Combined Board” with Note 3 for stacked sheets. The micrometer used for carrying out T411 om-89 is an Emveco 200-A Tissue Caliper Tester (Emveco, Inc., Newberg, Oreg.). The micrometer has a load of 2 kilo-Pascals, a pressure foot area of 2500 square millimeters, a pressure foot diameter of 56.42 millimeters, a dwell time of 3 seconds and a lowering rate of 0.8 millimeters per second. Caliper may be expressed in mils (0.001 inches) or microns.
[0025] As used herein the term “basis weight” generally refers to the conditioned weight per unit area of a tissue and is generally expressed as grams per square meter (gsm). Basis weight is measured herein using TAPPI test method T-220.
DETAILED DESCRIPTION
[0026] In general, the present disclosure is directed to creped tissue webs, and products produced therefrom. The creped webs and products are strong, soft, and have low amounts of slough, such as less than about 6 mg and more preferably less than about 4 mg, even at basis weights in excess of 16 gsm per ply and geometric mean tensile of less than about 500 g/3″ per ply. As such, the tissue webs are strong and soft, yet have low slough. Surprisingly, the combination of favorable properties is achieved without post treatment of the web with silicones, lotions, or the like.
[0027] In one embodiment, the tissue webs are creped, wherein the creping composition comprises a thermoplastic resin, such as the composition disclosed in U.S. Pat. No. 7,807,023, which is incorporated herein in a manner consistent with the present disclosure. The thermoplastic resin may be contained, for instance, in an aqueous dispersion prior to application to the creping surface. In one particular embodiment, the creping composition may comprise a non-fibrous olefin polymer. The creping composition, for instance, may comprise a film-forming composition and the olefin polymer may comprise an interpolymer of ethylene and at least one comonomer comprising an alkene, such as 1-octene. The creping composition may also contain a dispersing agent, such as a carboxylic acid. Examples of particular dispersing agents, for instance, include fatty acids, such as oleic acid or stearic acid.
[0028] In one particular embodiment, the creping composition may contain an ethylene and octene copolymer in combination with an ethylene-acrylic acid copolymer. The ethylene-acrylic acid copolymer is not only a thermoplastic resin, but may also serve as a dispersing agent. The ethylene and octene copolymer may be present in combination with the ethylene-acrylic acid copolymer in a weight ratio of from about 1:10 to about 10:1, such as from about 2:3 to about 3:2.
[0029] The olefin polymer composition may exhibit a crystallinity of less than about 50 percent, such as less than about 20 percent. The olefin polymer may also have a melt index of less than about 1000 g/10 min, such as less than about 700 g/10 min. The olefin polymer may also have a relatively small particle size, such as from about 0.05 micron to about 5 microns when contained in an aqueous dispersion.
[0030] In an alternative embodiment, the creping composition may contain an ethylene-acrylic acid copolymer. The ethylene-acrylic acid copolymer may be present in the creping composition in combination with a dispersing agent, such as a fatty acid.
[0031] Once applied to a tissue web, it has been discovered that the creping composition may form a discontinuous film depending upon the amount applied to the web. In other embodiments, the creping composition may be applied to a web such that the creping composition forms discrete treated areas on the surface of the web.
[0032] Compared to commercially available tissue, tissue prepared according to the present disclosure generally has lower slough even at higher basis weights.
[0000]
TABLE 1
Conditioned
Plies
Basis Weight
Slough
GMT
GMM
Sample
(No.)
(gsm)
(mg)
(g/3″)
(kg)
Kleenex ® Mainline
2
28.27
1.59
772
9.93
Facial Tissue
Puffs Basic ® Facial
2
29.82
6.13
665
7.18
Tissue
Puffs Plus ® Facial
2
42.79
4.98
797
10.11
Tissue
Puffs Ultra Strong and
2
40.03
9.69
1036
12.87
Soft ® Facial Tissue
Publix ® Facial Tissue
2
32.62
1.13
741
10.75
Up&Up ™ Everyday
2
30.75
3.79
814
10.59
Facial Tissue
Scotties ® 2-Ply
2
31.34
2.85
816
14.82
Facial Tissue
Inventive Sample
2
35.91
3.36
860
13.44
Inventive Sample
2
35.62
3.10
1004
15.75
[0033] Accordingly, in certain embodiments the disclosure provides a creped tissue product comprising two or more plies, wherein the product has a basis weight of at least about 33 gsm, and more preferably at least about 35 gsm, such as from about 33 to about 40 gsm. The tissue products preferably have a slough less than about 10 mg, more preferably less than about 8 mg and still more preferably less than about 4 mg. Further, tissue products having low slough and increased basis weight preferably have a geometric mean tensile less than about 1000 g/3″ and more preferably less than about 900 g/3″ and still more preferably less than about 800 g/3″.
[0034] In general, any suitable fibrous web may be treated in accordance with the present disclosure. For example, in one aspect, the base sheet can be a tissue product, such as a bath tissue, a facial tissue, a paper towel, a napkin, and the like. Fibrous products can be made from any suitable types of fiber.
[0035] Fibrous products made according to the present disclosure may include single-ply fibrous products or multiple-ply fibrous products. For instance, in some aspects, the product may include two plies, three plies, or more.
[0036] Fibers suitable for making fibrous webs comprise any natural or synthetic fibers including both nonwoody fibers and woody or pulp fibers. Pulp fibers can be prepared in high-yield or low-yield forms and can be pulped in any known method, including kraft, sulfite, high-yield pulping methods and other known pulping methods. Fibers prepared from organosolv pulping methods can also be used, including the fibers and methods disclosed in U.S. Pat. Nos. 4,793,898, 4,594,130, 3,585,104. Useful fibers can also be produced by anthraquinone pulping, exemplified by U.S. Pat. No. 5,595,628.
[0037] The fibrous webs of the present disclosure can also include synthetic fibers. For instance, the fibrous webs can include up to about 10 percent, such as up to about 30 percent or up to about 50 percent or up to about 70 percent or more by dry weight, to provide improved benefits. Suitable synthetic fibers include rayon, polyolefin fibers, polyester fibers, bicomponent sheath-core fibers, multi-component binder fibers, and the like. Synthetic cellulose fiber types include rayon in all its varieties and other fibers derived from viscose or chemically-modified cellulose.
[0038] Chemically treated natural cellulosic fibers can be used, for example, mercerized pulps, chemically stiffened or crosslinked fibers, or sulfonated fibers. For good mechanical properties in using web forming fibers, it can be desirable that the fibers be relatively undamaged and largely unrefined or only lightly refined. While recycled fibers can be used, virgin fibers are generally useful for their mechanical properties and lack of contaminants. Mercerized fibers, regenerated cellulosic fibers, cellulose produced by microbes, rayon, and other cellulosic material or cellulosic derivatives can be used. Suitable web forming fibers can also include recycled fibers, virgin fibers, or mixes thereof.
[0039] In general, any process capable of forming a web can also be utilized in the present disclosure. For example, a web forming process of the present disclosure can utilize creping, wet creping, double creping, recreping, double recreping, embossing, wet pressing, air pressing, through-air drying, hydroentangling, creped through-air drying, co-forming, airlaying, as well as other processes known in the art. For hydroentangled material, the percentage of pulp is about 70-85 percent.
[0040] Also suitable for articles of the present disclosure are fibrous sheets that are pattern densified or imprinted, such as the fibrous sheets disclosed in any of the following U.S. Pat. Nos. 4,514,345, 4,528,239, 5,098,522, 5,260,171, and 5,624,790, the disclosures of which are incorporated herein by reference to the extent they are non-contradictory herewith. Such imprinted fibrous sheets may have a network of densified regions that have been imprinted against a drum dryer by an imprinting fabric, and regions that are relatively less densified (e.g., “domes” in the fibrous sheet) corresponding to deflection conduits in the imprinting fabric, wherein the fibrous sheet superposed over the deflection conduits was deflected by an air pressure differential across the deflection conduit to form a lower-density pillow-like region or dome in the fibrous sheet.
[0041] The fibrous web can also be formed without a substantial amount of inner fiber-to-fiber bond strength. In this regard, the fiber furnish used to form the base web can be treated with a chemical debonding agent. The debonding agent can be added to the fiber slurry during the pulping process or can be added directly to the headbox. Suitable debonding agents that may be used in the present disclosure include cationic debonding agents such as fatty dialkyl quaternary amine salts, mono fatty alkyl tertiary amine salts, primary amine salts, imidazoline quaternary salts, silicone, quaternary salt and unsaturated fatty alkyl amine salts. Other suitable debonding agents are disclosed in U.S. Pat. No. 5,529,665, which is incorporated herein by reference in a manner consistent herewith.
[0042] While the creped webs of the present disclosure achieve low slough, such as less than about 4 mg at geometric mean tensile of less than about 500 g/3″ without post treatment, the webs may, in certain embodiments, be post treated to provide additional benefits. The types of chemicals that may be added to the web include absorbency aids usually in the form of cationic, or non-ionic surfactants, humectants and plasticizers such as low molecular weight polyethylene glycols and polyhydroxy compounds such as glycerin and propylene glycol. Materials that supply skin health benefits such as mineral oil, aloe extract, vitamin-E, silicone, lotions in general, and the like, may also be incorporated into the finished products. Such chemicals may be added at any point in the web forming process.
[0043] Fibrous webs that may be treated in accordance with the present disclosure may include a single homogenous layer of fibers or may include a stratified or layered construction. For instance, the fibrous web ply may include two or three layers of fibers. Each layer may have a different fiber composition. For example a three-layered headbox generally includes an upper head box wall and a lower head box wall. Headbox further includes a first divider and a second divider, which separate three fiber stock layers.
[0044] Each of the fiber layers comprises a dilute aqueous suspension of papermaking fibers. The particular fibers contained in each layer generally depend upon the product being formed and the desired results. For instance, the fiber composition of each layer may vary depending upon whether a bath tissue product, facial tissue product or paper towel is being produced. In one aspect, for instance, the middle layer contains southern softwood kraft fibers either alone or in combination with other fibers such as high yield fibers. Outer layers, on the other hand, contain softwood fibers, such as northern softwood kraft. In an alternative aspect, the middle layer may contain softwood fibers for strength, while the outer layers may comprise hardwood fibers, such as eucalyptus fibers, for a perceived softness.
[0045] In general, any process capable of forming a base sheet may be utilized in the present disclosure. For example, an endless traveling forming fabric, suitably supported and driven by rolls, receives the layered papermaking stock issuing from the headbox. Once retained on the fabric, the layered fiber suspension passes water through the fabric. Water removal is achieved by combinations of gravity, centrifugal force and vacuum suction depending on the forming configuration. Forming multi-layered paper webs is also described and disclosed in U.S. Pat. No. 5,129,988, which is incorporated herein by reference in a manner that is consistent herewith.
[0046] Preferably the formed web is dried by transfer to the surface of a rotatable heated dryer drum, such as a Yankee dryer. In accordance with the present disclosure, the creping composition may be applied topically to the tissue web while the web is traveling on the fabric or may be applied to the surface of the dryer drum for transfer onto one side of the tissue web. In this manner, the creping composition is used to adhere the tissue web to the dryer drum. In this embodiment, as the web is carried through a portion of the rotational path of the dryer surface, heat is imparted to the web causing most of the moisture contained within the web to be evaporated. The web is then removed from the dryer drum by a creping blade. Creping the web, as it is formed, further reduces internal bonding within the web and increases softness. Applying the creping composition to the web during creping, on the other hand, may increase the strength of the web.
[0047] In another embodiment the formed web is transferred to the surface of the rotatable heated dryer drum, which may be a Yankee dryer. The press roll may, in one embodiment, comprise a suction pressure roll. In order to adhere the web to the surface of the dryer drum, a creping adhesive may be applied to the surface of the dryer drum by a spraying device. The spraying device may emit a creping composition made in accordance with the present disclosure or may emit a conventional creping adhesive. The web is adhered to the surface of the dryer drum and then creped from the drum using the creping blade. If desired, the dryer drum may be associated with a hood. The hood may be used to force air against or through the web.
[0048] In other embodiments, once creped from the dryer drum, the web may be adhered to a second dryer drum. The second dryer drum may comprise, for instance, a heated drum surrounded by a hood. The drum may be heated from about 25° C. to about 200° C., such as from about 100° C. to about 150° C.
[0049] In order to adhere the web to the second dryer drum, a second spray device may emit an adhesive onto the surface of the dryer drum. In accordance with the present disclosure, for instance, the second spray device may emit a creping composition as described above. The creping composition not only assists in adhering the tissue web to the dryer drum, but also is transferred to the surface of the web as the web is creped from the dryer drum by the creping blade. Once creped from the second dryer drum, the web may, optionally, be fed around a cooling reel drum and cooled prior to being wound on a reel.
[0050] In addition to applying the creping composition during formation of the fibrous web, the creping composition may also be used in post-forming processes. For example, in one aspect, the creping composition may be used during a print-creping process. Specifically, once topically applied to a fibrous web, the creping composition has been found well-suited to adhering the fibrous web to a creping surface, such as in a print-creping operation.
[0051] For example, once a fibrous web is formed and dried the creping composition may be applied to at least one side of the web and the at least one side of the web may then be creped. In general, the creping composition may be applied to only one side of the web and only one side of the web may be creped, the creping composition may be applied to both sides of the web and only one side of the web is creped, or the creping composition may be applied to each side of the web and each side of the web may be creped.
[0052] In one embodiment the creping composition may be added to one side of the web by creping, using either an in-line or off-line process. A tissue web is passed through a first creping composition application station that includes a nip formed by a smooth rubber press roll and a patterned rotogravure roll. The rotogravure roll is in communication with a reservoir containing a first creping composition. The rotogravure roll applies the creping composition to one side of web in a preselected pattern. The web is then contacted with a heated roll, which can be heated to a temperature, for instance, up to about 200° C., and more preferably from about 100° C. to about 150° C. In general, the web can be heated to a temperature sufficient to dry the web and evaporate any water. It should be understood, that besides the heated roll, any suitable heating device can be used to dry the web. For example, in an alternative embodiment, the web can be placed in communication with an infra-red heater in order to dry the web.
[0053] Besides using a heated roll or an infra-red heater, other heating devices can include, for instance, any suitable convective oven or microwave oven.
[0054] From the heated roll, the web can be advanced by pull rolls to a second creping composition application station, which includes a transfer roll in contact with a rotogravure roll, which is in communication with a reservoir containing a second creping composition. The second creping composition may be applied to the opposite side of the web in a preselected pattern. The first and second creping compositions may contain the same ingredients or may contain different ingredients. Alternatively, the creping compositions may contain the same ingredients in different amounts as desired. Once the second creping composition is applied the web is adhered to a creping roll by a press roll and carried on the surface of the creping drum for a distance and then removed therefrom by the action of a creping blade. The creping blade performs a controlled pattern creping operation on the second side of the tissue web. Although the creping composition is being applied to each side of the tissue web, only one side of the web undergoes a creping process. It should be understood, however, that in other embodiments both sides of the web may be creped.
[0055] Once creped the tissue web may be pulled through a drying station. The drying station can include any form of a heating unit, such as an oven energized by infra-red heat, microwave energy, hot air, or the like. drying station may be necessary in some applications to dry the web and/or cure the creping composition. Depending upon the creping composition selected, however, in other applications a drying station may not be needed.
[0056] The creping compositions of the present disclosure are typically transferred to the web at high levels, such that at least about 30 percent of the creping composition applied to the Yankee is transferred to the web, more preferably at least about 45 percent is transferred and still more preferably at least about 60 percent is transferred. Generally from about 45 to about 65 percent of the creping composition applied to the Yankee dryer is transferred to the web. Thus, the amount of creping additive transferred to the sheet is a function of the amount of creping additive applied to the Yankee dryer.
[0057] The total amount of creping composition applied to each side of the web can be in the range of from about 0.1 to about 10 percent by weight, based upon the total weight of the web, such as from about 0.3 to about 5 percent by weight, such as from about 0.5 to about 3 percent by weight. To achieve the desired additive application levels the add on rate of creping composition to the dryer, measured as mass (i.e., mg) per unit area of dryer surface (i.e., m 2 ), may range from about 50 to about 300 mg/m 2 , and still more preferably from about 100 to about 200 mg/m 2 .
[0058] Further, the creping composition is applied to the paper web so as to cover from about 15 to about 100 percent of the surface area of the web. More particularly, in most applications, the creping composition will cover from about 20 to about 60 percent of the surface area of each side of the web.
[0059] In one aspect, fibrous webs made according to the present disclosure can be incorporated into multiple-ply products. For instance, in one aspect, a fibrous web made according to the present disclosure can be attached to one or more other fibrous webs for forming a wiping product having desired characteristics. The other webs laminated to the fibrous web of the present disclosure can be, for instance, a wet-creped web, a calendered web, an embossed web, a through-air dried web, a creped through-air dried web, an uncreped through-air dried web, an airlaid web, and the like.
[0060] In one aspect, when incorporating a fibrous web made according to the present disclosure into a multiple-ply product, it may be desirable to only apply the creping composition to one side of the fibrous web and to thereafter crepe the treated side of the web. The creped side of the web is then used to form an exterior surface of a multiple-ply product. The untreated and uncreped side of the web, on the other hand, is attached by any suitable means to one or more plies.
[0061] In multiple-ply products, the basis weight of each fibrous web present in the product may vary. In general, the total basis weight of a multiple-ply product will be from about 33 to about 60 gsm, such as from about 33 to about 45 gsm, and more preferably from about 33 to about 40 gsm. In particularly preferred embodiments the tissue product is a multi-ply facial tissue wherein each ply has a basis weight from about 16 to about 30 gsm, such as from about 16.5 to about 22.5 gsm, and more preferably from about 17 to about 20 gsm.
[0062] Webs made according to the above processes, and products formed therefrom, have relatively low slough, such as less than about 8 mg, more preferably less than about 6 mg and still more preferably less than about 4 mg. For instance, for a web having a basis weight from about 16 to about 25 gsm, or a product having a basis weight from about 33 to 50 gsm, slough may vary from about 1 to about 8 mg, such as from about 2 to about 6 mg, or from about 2 to about 4 mg. Surprisingly, it has been discovered that treatment of tissue webs with the creping composition of the present disclosure results in tissue products having lower slough at a given basis weight relative to creped tissue products prepared according to the prior art. For example, tissue products of the present invention have sloughs from about 3 to about 5 mg at a basis weight of about 36 gsm.
[0063] Moreover, the relatively low sloughs are achieved at relatively modest geometric mean tensile strengths. This provides a tissue having the requisite softness and stiffness, without excessive pilling. For example, creped tissue products prepared according to the present disclosure have geometric mean tensile strengths of less than about 1000 g/3″, and more preferably less than about 900 g/3″, such as from about 700 to about 1000 g/3″.
[0064] In addition to having low slough, webs and products prepared according to the present disclosure have improved softness, especially when prepared at higher basis weights, such as greater than about 16.5 gsm per ply. For example, tissue webs having a basis weight of at least about 16.5 gsm have a tissue softness value (also referred to herein as a “TS7 value”), measured using EMTEC Tissue Softness Analyzer (“TSA”) (Emtec Electronic GmbH, Leipzig, Germany) as described in the Test Methods section, from about 8 to about 10. In a particularly preferred embodiment the present disclosure provides a tissue product comprising at least one creped web having a basis weight greater than about 16 gsm, a slough less than about 5 mg and a TSA value from about 8 to about 10.
Test Methods
[0065] Slough
[0066] Slough, also referred to as “pilling,” is a tendency of a tissue sheet to shed fibers or clumps of fibers when rubbed or otherwise handled. The slough test provides a quantitative measure of the abrasion resistance of a tissue sample. More specifically, the test measures the resistance of a material to an abrasive action when the material is subjected to a horizontally reciprocating surface abrader. The equipment and method used is similar to that described in U.S. Pat. No. 6,808,595, the disclosure of which is herein incorporated by reference to the extent that it is non-contradictory herewith.
[0067] FIG. 2 is a schematic diagram of the test equipment used to measure pilling. Shown is the abrading spindle or mandrel 35 , a double arrow 36 showing the motion of the mandrel 35 , a sliding clamp 37 , a slough tray 38 , a stationary clamp 39 , a cycle speed control 40 , a counter 41 , and start/stop controls 42 . The abrading spindle 35 consists of a stainless steel rod, 0.5″ in diameter with the abrasive portion consisting of a 0.005″ deep diamond pattern knurl extending 4.25″ in length around the entire circumference of the rod. The abrading spindle 35 is mounted perpendicularly to the face of the instrument 33 such that the abrasive portion of the abrading spindle 35 extends out its entire distance from the face of the instrument 33 . On each side of the abrading spindle 35 is located a pair of clamps 37 and 39 , one movable 37 and one fixed 39 , spaced 4″ apart and centered about the abrading spindle 35 . The movable clamp 37 (weighing approximately 102.7 grams) is allowed to slide freely in the vertical direction, the weight of the movable clamp 37 providing the means for insuring a constant is tension of the tissue sheet sample over the surface of the abrading spindle 35 .
[0068] Prior to testing, all tissue sheet samples are conditioned at 23±1° C. and 50±2% relative humidity for a minimum of 4 hours. Using a JDC-3 or equivalent precision cutter, available from Thwing-Albert Instrument Company, Philadelphia, Pa., the tissue sheet sample specimens are cut into 3±0.05″ wide×7″ long strips (note: length is not critical as long as specimen can span distance so as to be inserted into the clamps 37 and 39 ). For tissue sheet samples, the MD direction corresponds to the longer dimension.
[0069] Each tissue sheet sample is weighed to the nearest 0.1 mg. One end of the tissue sheet sample is clamped to the fixed clamp 39 , the sample then loosely draped over the abrading spindle or mandrel 35 and clamped into the sliding clamp 37 . The entire width of the tissue sheet sample should be in contact with the abrading spindle 35 . The sliding clamp 37 is then allowed to fall providing constant tension across the abrading spindle 35 .
[0070] The abrading spindle 35 is then moved back and forth at an approximate 15 degree angle from the centered vertical centerline in a reciprocal horizontal motion against the tissue sheet sample for 20 cycles (each cycle is a back and forth stroke), at a speed of 170 cycles per minute, removing loose fibers from the surface of the tissue sheet sample. Additionally the spindle rotates counter clockwise (when looking at the front of the instrument) at an approximate speed of 5 RPMs. The tissue sheet sample is then removed from the jaws 37 and 39 and any loose fibers on the surface of the tissue sheet sample are removed by gently shaking the tissue sheet sample. The tissue sheet sample is then weighed to the nearest 0.1 mg and the weight loss calculated. Ten tissue sheet specimens per sample are tested and the average weight loss value in milligrams (mg) is recorded, which is the Pilling value for the side of the tissue sheet being tested.
[0071] Tissue Softness
[0072] Sample softness was analyzed using an EMTEC Tissue Softness Analyzer (“TSA”) (Emtec Electronic GmbH, Leipzig, Germany). The TSA comprises a rotor with vertical blades which rotate on the test piece applying a defined contact pressure. Contact between the vertical blades and the test piece creates vibrations, which are sensed by a vibration sensor. The sensor then transmits a signal to a PC for processing and display. The signal is displayed as a frequency spectrum. The frequency analysis in the range of approximately 200 Hz to 1000 Hz represents the surface smoothness or texture of the test piece. A high amplitude peak correlates to a rougher surface. A further peak in the frequency range between 6 kHZ and 7 kHZ represents the softness of the test piece. The peak in the frequency range between 6 kHZ and 7 kHZ is herein referred to as the TS7 Softness Value and is expressed as dB V2 rms. The lower the amplitude of the peak occurring between 6 kHZ and 7 kHZ, the softer the test piece.
[0073] Test samples were prepared by cutting a circular sample having a diameter of 112.8 mm. All samples were allowed to equilibrate at TAPPI standard temperature and humidity conditions for at least 24-hours prior to completing the TSA testing. Only one ply of tissue is tested. Multi-ply samples are separated into individual plies for testing. The sample is placed in the TSA with the softer (dryer or Yankee) side of the sample facing upward. The sample is secured and the TS7 Softness Values measurements are started via the PC. The PC records, processes and stores all of the data according to standard TSA protocol. The reported TS7 Softness Value is the average of 5 replicates, each one with a new sample.
[0074] Tensile
[0075] Samples for tensile strength testing are prepared by cutting a 3 inches (76.2 mm)×5 inches (127 mm) long strip in either the machine direction (MD) or cross-machine direction (CD) orientation using a JDC Precision Sample Cutter (Thwing-Albert Instrument Company, Philadelphia, Pa., Model No. JDC 3-10, Ser. No. 37333). The instrument used for measuring tensile strengths is an MTS Systems Sintech 11S, Serial No. 6233. The data acquisition software is MTS TestWorks™ for Windows Ver. 4 (MTS Systems Corp., Research Triangle Park, N.C.). The load cell is selected from either a 50 Newton or 100 Newton maximum, depending on the strength of the sample being tested, such that the majority of peak load values fall between 10 and 90 percent of the load cell's full scale value. The gauge length between jaws is 2±0.04 inches (50.8±1 mm). The jaws are operated using pneumatic-action and are rubber coated. The minimum grip face width is 3 inches (76.2 mm), and the approximate height of a jaw is 0.5 inches (12.7 mm). The crosshead speed is 10±0.4 inches/min (254±1 mm/min), and the break sensitivity is set at 65 percent. The sample is placed in the jaws of the instrument, centered both vertically and horizontally. The test is then started and ends when the specimen breaks. The peak load is recorded as either the “MD tensile strength” or the “CD tensile strength” of the specimen depending on the sample being tested. At least six (6) representative specimens are tested for each product, taken “as is,” and the arithmetic average of all individual specimen tests is either the MD or CD tensile strength for the product.
[0076] For multiple-ply products tensile testing is done on the number of plies expected in the finished product. For example, 2-ply products are tested two plies at one time and the recorded MD and CD tensile strengths are the strengths of both plies.
EXAMPLES
[0077] Inventive sample codes were made using a wet pressed process utilizing a Crescent Former. Initially, northern softwood kraft (NSWK) pulp was dispersed in a pulper for 30 minutes at 4 percent consistency at about 100° F. The NSWK pulp was then transferred to a dump chest and subsequently diluted to approximately 3 percent consistency. The NSWK pulp was refined at about 1 HP-days/MT. Softwood fibers were then pumped to a machine chest where they were mixed with 2 kg/MT of Kymene® 920A (Ashland Water Technologies, Wilmington, Del.) and 1 kg/MT Baystrength 3000 (Kemira, Atlanta, Ga.) of prior to the headbox. The softwood fibers were added to the middle side layer in the 3-layer tissue structure. The virgin NSWK fiber content contributed approximately 32 percent of the final sheet weight.
[0078] Eucalyptus hardwood kraft (EHWK) pulp was dispersed in a pulper for 30 minutes at about 4 percent consistency at about 100° F. The EHWK pulp was then transferred to a dump chest and diluted to about 3 percent consistency. The EHWK pulp fibers were then pumped to a machine chest where they were mixed with 2 kg/MT of Kymene® 920A. These fibers were added to dryer and felt layers, as indicated in the Table below.
[0000]
TABLE 2
Weight %
Layer
Fiber Type
Additives
(total web)
Dryer
EHWK
2 kg/MT Kymene ® 920A
44
Middle
NSWK
2 kg/MT Kymene ® 920A
32
1 kg/MT Baystrength ™ 3000
Felt
EHWK
2 kg/MT Kymene ® 920A
24
[0079] The pulp fibers from the machine chests were pumped to the headbox at a consistency of about 0.1 percent. Pulp fibers from each machine chest were sent through separate manifolds in the headbox to create a 3-layered tissue structure. The fibers were deposited onto a felt using a Crescent Former.
[0080] The wet sheet, about 10 to 20 percent consistency, was adhered to a Yankee dryer, traveling at about 2000 fpm (610mpm) through a nip via a pressure roll. The consistency of the wet sheet after the pressure roll nip (post-pressure roll consistency or PPRC) was approximately 40 percent. The wet sheet is adhered to the Yankee dryer due to the creping composition that is applied to the dryer surface. A spray boom situated underneath the Yankee dryer sprayed the creping composition onto the dryer surface.
[0081] Two different creping compositions were evaluated. A conventional creping composition comprising, by weight on a solids basis, 70 percent Crepetrol™ Xcel and 30 percent Crepetrol™ 874 (both commercially available from Ashland Water Technologies, Wilmington, Del.) was prepared at about 1 percent solids. The flow rates of the conventional creping chemistry were varied to deliver a total addition of about 10 mg/m 2 spray coverage on the Yankee Dryer at the desired component ratio. A non-fibrous olefin dispersion, sold under the trade name HYPOD 8510 (Dow Chemical Co., Midland, Mich.) was also evaluated. The HYPOD 8510 was prepared at 30 percent solids and delivered at a total addition of about 200 mg/m 2 spray coverage on the Yankee Dryer.
[0000]
TABLE 3
Total Addition
Creping Composition
Creping Components (wt %)
(mg/m 2 )
Conventional
Crepetrol ™ Xcel (70%)
10
Crepetrol ™ 874 (30%)
Non-fibrous Olefin
HYPOD 8510
200
[0082] The sheet was dried to about 98 to 99 percent consistency as it traveled on the Yankee dryer and to the creping blade. The creping blade subsequently scraped the tissue sheet and a portion of the creping composition off the Yankee dryer. The creped tissue basesheet was then wound onto a core traveling at about 1575 fpm (480 mpm) into soft rolls for converting. Two soft rolls of the creped tissue were then rewound, calendered, and plied together so that both creped sides were on the outside of the 2-ply structure. Mechanical crimping on the edges of the structure held the plies together. The plied sheet was then slit on the edges to a standard width of approximately 8.5 inches, and cut to facial tissue length. Tissue samples were conditioned and tested. Table 4 summarizes the conditions under which the samples of the present example were prepared. Table 5 summarizes the physical properties of the samples prepared as described herein.
[0000]
TABLE 4
Finished
Add On
Web Target Basis
Product
Sample
Creping Composition
(mg/m 2 )
Weight (gsm)
Plies (No.)
1
Conventional
10
16.2
2
2
Conventional
10
17.75
2
3
Conventional
10
20.4
2
4
Non-fibrous Olefin
200
14.2
2
5
Non-fibrous Olefin
200
16.8
2
6
Non-fibrous Olefin
200
17.75
2
7
Non-fibrous Olefin
200
18.5
2
8
Non-fibrous Olefin
200
21.3
2
[0000]
TABLE 5
Basis
Single Ply
Weight
Slough
Caliper
Single Ply Basis
Sample
(gsm)
(mg)
GMT (g/3″)
(μm)
Weight (gsm)
1
32.9
7.5
702
238.8
16.4
2
35.6
8.2
708
249.6
17.8
3
40.0
10.5
841
259.1
20.0
4
29.4
3.5
711
212.2
14.7
5
33.0
3.8
802
226.3
16.5
6
35.5
3.7
876
237.6
17.8
7
37.6
3.8
1082
236.0
18.8
8
41.9
5.5
1184
256.0
21.0
[0083] Referring to FIG. 2 , the effect of basis weight on slough is illustrated for the two creping compositions of the present example. As can be seen from FIG. 2 , for tissue webs treated with conventional creping compositions, slough increases significantly as basis weight increases. However, for inventive an increase in basis weight is accompanied by only a negligible increase in slough. Indeed, even when basis weight is increased by as much as 28 percent, slough increases by only about 0.3 mg.
[0084] In this manner, it is believed that the additive composition provides strength to the outer most layer of the web without significantly increasing the geometric mean tensile of the web. Of particular advantage, these results are obtained without a substantial increase in stiffness of the tissue web and without a substantial decrease in the perceived softness.
[0085] To further explore the relationship between the non-fibrous olefin creping composition, basis weight and slough, additional tissue products were prepared as described above, but the creping composition was added at two different add-on levels—200 mg/m 2 and 100 mg/m 2 . The physical properties are summarized in the table below.
[0000]
TABLE 6
Single
Add On
Basis Weight
GMT
Ply Basis
MD
CD
Slough
(mg/m 2 )
(gsm)
(g/3″)
Weight (gsm)
Slope
Slope
(mg)
100
32.54
792.40
16.27
11.03
12.92
5.30
100
35.00
834.42
17.50
10.77
11.87
5.00
200
30.13
771.13
15.06
10.33
13.87
3.78
200
35.76
821.32
17.88
11.68
12.68
5.22
[0086] Finally, to explore the relationship between basis weight, softness and slough, additional inventive samples were prepared as described above. The non-fibrous olefin creping composition was applied at an add-on level of 100 mg/m 2 to prepare both the control and inventive samples. Tissue softness was measured using the TSA instrument as described above. The physical properties of the control and inventive samples, as well as comparative commercial tissue samples, are summarized in the table below.
[0000]
TABLE 7
Basis
Add-On
Weight
GMT
GMM
Slough
Sample
Creping Composition
(mg/m 2 )
(gsm)
(g/3″)
(kg)
(mg)
TS7
Control
Non-fibrous Olefin
100
28.6
825
11.64
1.4
10.8
Inventive
Non-fibrous Olefin
100
33.3
805
6.99
1.9
9.7
Inventive
Non-fibrous Olefin
100
36.6
790
9.31
3.9
9.2
Publix ® Facial Tissue
—
—
32.62
741
10.75
1.13
12.7
Puffs Basic ® Facial Tissue
—
—
29.82
665
7.18
6.13
10.2
Scotties ® 2-Ply Facial Tissue
—
—
31.34
816
14.82
2.85
12.6
Up&Up ™ Everyday Facial Tissue
—
—
30.75
814
10.59
3.79
11.1
[0087] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims. | Low slough, high basis weight tissue webs and products are provided. The tissue webs generally have basis weights greater than about 16 grams per square meter (gsm), while maintaining less than about 4 mg of slough. All while yielding tissue products that are both thick and soft. | 3 |
FIELD OF THE INVENTION
The present invention relates generally to hydrodynamic conditioning of textile fabrics, and, more particularly, to a method for hydrodynamically treating the multiple layers of tubular knitted fabrics.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram of the hydrodynamic conditioning and finishing process of the present invention;
FIG. 2 is a schematic view of the hydrodynamic conditioning process of the current invention;
FIGS. 3A through 3D are graphical illustrations of the changes in structure of the loops of tubular knitted fabrics that are created by the hydrodynamic conditioning and finishing process of the present invention; and
FIG. 4 is a table of exemplary test data for the hydrodynamic conditioning and finishing process of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Certain exemplary embodiments of the present invention are described below and illustrated in the attached Figures. The embodiments described are only for purposes of illustrating the present invention and should not be interpreted as limiting the scope of the invention, which, of course, is limited only by the claims below. Other embodiments of the invention, and certain modifications and improvements of the described embodiments, will occur to those skilled in the art, and all such alternate embodiments, modifications and improvements are within the scope of the present invention.
Definitions:
“Bursting Strength” refers to the force required in pounds to rupture a fabric when performed in accordance with a standard test method for the particular fabric construction.
“Dimensional Stability” refers to the ability of a textile material to maintain, or return to, its original geometric configuration.
“High Cotton Content” refers to fabric having a cotton content, by weight, of greater than about 50 percent.
“Hydroenhancement” refers to a process whereby woven or knitted fabrics are subjected to dynamic fluid jets to achieve certain physical properties.
“Hydroentanglement” refers to the process for forming a fabric by mechanically wrapping wrapping and knotting fibers in a web, typically non-woven, through the use of high velocity, high pressure jets or columns of water.
“Pilling” refers to the tendency of fibers in a textile to work loose from a fabric surface and form balls or matts of fiber that remain attached to the surface of the fabric.
“Residual Shrinkage” refers to the amount of shrinkage in the length and width directions, expressed in percent, which the finished fabric and/or article of apparel may still undergo when subjected to home laundering by the consumer and/or end user.
“Torque” in a tubular knitted fabric refers to the tendency of a fabric to skew or twist as a result of shifting of the courses and wales.
Hydroentanglement and hydroenhancement are generally known in the art. Hydroentanglement conventionally has been used non-woven fabrics where one or more layers or batts of loose fibers have been subjected to fluid jets to intermingle and permanently interlock the fibers into a more composite mass. Hydroenhancement, on the other hand, has typically been employed to create certain surface effects or patterns on the surfaces of single-ply fabrics.
The present invention is directed to a method for hydrodynamically treating tubular, or other multi-ply knitted fabric. More specifically, the method produces a tubular knitted fabric that is conditioned by hydrodynamic treatment without permanently entangling or permanently interlocking the knitted fabric layers together, while creating a knitted fabric having a low level of residual shrinkage. As defined above, residual shrinkage refers to the amount of shrinkage which a fabric or apparel will still undergo after being subjected to repeated home launderings. The lower the level of residual shrinkage, the more desirable is the finished fabric, or apparel formed therefrom. Additionally, the pressure of the jet nozzles does not skew or spiral the fabric. Further, the surface of the fabric is aesthetically pleasing, having a level and relatively smooth surface and a soft hand.
Turning now to FIG. 1 , the one embodiment of the process of the present invention is illustrated in a flow diagram. The process begins with the formation of a tubular knitted fabric (Step 110 ). In the embodiments described herein, the tubular knitted fabrics have a high cotton content. In one embodiment, the tubular knitted fabric comprises 100 percent open end spun cotton that is circular knitted; however, the present invention is not limited to yarns formed by any particular method. As is known in the art, circular knitting involves the production of fabric on a circular knitting machine to form a tube, with the yarns forming the tube running continuously around the fabric. The initially knitted, but untreated tubular knitted fabric is referred to as “greige,” or unbleached fabric.
Following formation of the tubular knitted fabric, rolls of the greige fabric are readied for hydrodynamic treatment. Referring also to FIG. 2 , the hydrodynamic treatment (Step 120 ) of the present process is shown in detail. Hydrodynamic treatment, or hydrotreatment, uses a mechanical action via fine, high-velocity fluid jets that are directed against the flat surfaces of a fabric. Conventionally, however, where multiple layers or loosely formed batts are involved, this treatment has the effect of permanently entangling the layers or batts into a single composite structure. FIG. 2 is exemplary of one commercially available entangling machine. In particular, the machine employed in the current process is a Fleeissner, two-stage belt and drum entangler having five jet manifolds. While a Fleeissner entangler has been described herein, those skilled in the art will appreciate that other entanglers with similar operating capabilities may also be used to accomplish the method described herein. The machine may comprise a straightener/feeder 121 which typically aligns and feeds fabric to the downstream fluid treatment. The inventors were able to use the same straightener/feeder 121 to feed a tubular knitted fabric. A support member, or conveyor belt 122 , is provided to traverse the tubular fabric via a series of spaced rollers 123 beneath the first series of three jet manifolds 125 . The belt 122 used in the present process is a 103 Mesh PET type belt available from Albany International of Albany, N.Y. A jet strip available from Gozz Beckert of Germany is used in conjunction with the belt. The parallel spaced manifolds 125 each comprise high velocity jet nozzles (not shown), usually arranged in multiple rows, wherein the jets are each between about 0.005 and 0.007 inches in diameter and arranged at a density of between about 30 and 60 jets per square inch. The downstream manifolds 127 are similarly configured.
The manifolds 125 , 127 on the Fleeissner entangler are variably controllable for hydrodynamic jet pressures of between about 25 bar and 250 bar; however, the entangler is typically operated at the higher end of the pressure range for at least two reasons: (1) entanglers are conventionally designed for forming non-woven constructions of interlocked loose fibers, and (2) higher pressures conventionally are believed necessary to obtain maximum entanglement and optimal surface effects. The machine and belt 122 can operate at feed-through rates of up to about 350 meters per minute. As will be discussed in greater detail below, a range of speed and pressure combinations have been found to provide acceptable results in the method described and claimed herein.
After passing beneath the first series of jet manifolds 125 , the fabric advances around a cylindrical drum 126 wherein the opposite, or bottom, side of the tubular knitted fabric is subjected to similar hydrodynamic treatment. The drum 126 also comprises spaced fluid-permeable openings (not shown) that are configured like a mesh screen. While the number and arrangement of manifolds 127 may vary, the Fleeissner two-stage entangler comprises a series of two jet manifolds 127 .
Upon exiting the second series of jet manifolds 127 , the hydrodynamically treated fabric is next fed through a conventional dryer where excess moisture in the fabric is substantially removed. As will be described in greater detail below, the hydrodynamically treated fabric has physical properties that are substantially different from the griege fabric. For example, the hydrodynamic treatment has the effect of increasing the dyeable surface areas of the yarns such that dye uptake coverage is increased. Also, it is anticipated that the required dwell, or cycle, time in a conventional dye bath or bleach bath will be reduced since the fabric will have been pre-cleaned by the hydrodynamic treatment. Further, the inventors have unexpectedly found that at manifold pressures at between about 25 bar and 40 bar, the two layers of the tubular knitted fabric are not permanently entangled; rather, the hydrodynamically treated fabric may be subsequently finished, without the need for any manipulation to separate the two layers. Thus, any minimal entanglement which may be created will be removed during the conventional subsequent processing.
Turning again to FIG. 1 , the hydrodynamically treated fabric is finished used conventional techniques known in the art. For instance, depending upon the desired application, the dried fabric may be dyed and/or bleached. As is also conventional in the art, griege fabric is batched for bleaching or dyeing. Where the treated fabric is 100 percent cotton or a derivative thereof, the knitted fabric is immersed in a dye bath (Step 130 ) and dyed with reactive type dyestuffs. After dyeing, the fabric is padded (Step 140 ) to remove excess dyestuff. If other fiber types are included, separate dye baths may be required. For the exemplary data shown in FIG. 4 , all of the tested fabric was bleached, and not dyed.
The dyed and padded fabric is next dried (Step 150 ) in a conventional manner at belt speeds and temperatures well known in the art. As also described in greater detail below, the dyeing or bleaching, and drying steps further enhance the desired properties of the hydrodynamically treated fabric. Following the drying step, the tubular knitted fabric is subjected to a conventional calendering operation (Step 160 ), which further conditions and compacts the fabric, while improving the hand of the fabric.
Referring now to FIG. 3 , the effects of the hydrodynamic treatment of the tubular knitted fabric and subsequent finishing are graphically illustrated. As shown in FIG. 3A , illustrative yarns 312 in two layers of the greige fabric show minimal signs of fiber breakage, or barbing, which tends to create hooks extending from the yarn surfaces. Further, and as shown in the Figure, gaps X, Y, which represent the overlap of the two loops in a knitted course, are present between the loops of each yarn 312 in the top A and bottom B layers of the fabric, respectively. As an example of the process of the present invention, prior to hydrodynamic treatment, the gaps X, Y, as would normally be expected, might be about ⅛ inches; however, this is exemplary of one of many possible dimensions depending upon the various knitting parameters as well as the yarn sizes, etc. The fabric has an initial weight basis of 2.15 ounces per square yard.
Referring to FIG. 3B , the effects of the hydrodynamic treatment are illustrated. Whereas conventional hydrodynamic treatment has the effect of permanently entangling the fibers of overlying layers, the inventors have found that at sufficiently low hydrodynamic pressures, the fibers comprising the yarns tend to fracture, creating a plurality of barbs 312 a over their entire surface areas, yet do not interlock the discrete layers A and B in any appreciable, measurable fashion. As shown in FIG. 3B , at pressures between about 25 bar and 40 bar (absolute), the barbs 312 a of yarns 312 tend to interlock the individual knitted loops of the fabric together. Further, following the hydrodynamic treatment process of the current invention, the gaps X, Y are reduced through both the compacting action of the hydrodynamic treatment and the interlocking of the barbs 312 a to between approximately ⅙ inches (top layer A) and approximately 1/16 inches (bottom layer B). The creation and initial interlocking of the barbs facilitates the reduction in the size of the gaps X, Y during the subsequent processing, as described below. The weight basis of the fabric has also increased to between 4.23 and 4.51 ounces per square yard.
Turning to FIG. 3C , following the dyeing and bleaching step (Step 130 ), and padding of the dyed or bleached fabric (Step 140 ), the average gap X, Y for the top A and bottom B layers of the knitted fabric is further reduced to between approximately ⅛ inches and 1/16 inches, respectively. Subsequent drying of the dyed or bleached fabric (Step 150 ), the gap X, Y is further reduced through drying action to between approximately 1/32 inches, respectively, for the top A and bottom B layers. The weight basis of the fabric remains between 4.06 and 4.44 ounces per square yard.
Finally, and referring to FIG. 3D , following calendaring, the gaps X, Y are further reduced to between about 0.0 inches and less than 1/32 inches for the top A and bottom B layers, respectively. In effect, then, the combined processes of the hydrodynamic treatment, dyeing/bleaching, drying, and calendaring causes the tubular knitted fabric gaps to close, unexpectedly yielding a substantially more dimensionally stable tubular knitted fabric than has been heretofore produced.
Turning lastly to FIG. 4 , detailed numerical measurements of the results for various pressures and line speed combinations of the current process are shown. FIG. 4 comprises three separate data sections: Untreated Fabric (Greige), Hydrodynamically Treated Fabric, and Bleached and/or Dyed Fabric. By way of example, the Untreated Fabric comprises measured data for a 100 percent tubular knitted jersey fabric comprising, a 28/1 yarn and having an initial width (comprising two overlying layers) of 23.625 inches and a weight basis of 2.15 ounces per square yard. The weight basis is measured in accordance with Standard ASTM D-3776-96, “Standard Test Method for Mass Per Unit Area (Weight) of Fabric. As shown in the table, for one embodiment the initially formed greige fabric had a residual shrinkage after five home launderings of 15.2 percent in the length dimension and 12.3 percent in the width dimension, when laundered and measured in accordance with AATCC Test Method 135-1995, “Dimensional Changes in Automatic Home Laundering of Woven and Knit Fabrics.” Dimensional changes in the length and width are expressed as a percentage of the initial dimension of the specimen. As will be appreciated by those of ordinary skill in the art, the greater the dimensional changes that result from home laundering, the less desirable and/or less predictable is the fabric, or apparel made therefrom, to the ultimate consumer. For tubular knitted fabric applications, maximum dimensional change, or shrinkage, of 5 percent or less in both the length and width directions is considered desirable.
As shown for the Hydrodynamically Treated Fabric in FIG. 4 , various combinations of jet manifold pressures and line speeds were tested and measured. As will be understood, minor variations in handling of the fabric following hydrodynamic treatment, or hydrodynamic treatment followed by bleaching and/or dyeing, in combination with errors in measurements, result is minor variations in test results for similarly processed specimens. At one end of the spectrum of pressure/speed combinations, for example, a specimen was hydrodynamically treated at a pressure of 40 bar and a line speed of 120 meters per minute. The residual shrinkage was reduced by the hydrodynamic treatment to about 14 percent in the length dimension and 3.6 percent in the width dimension after five home launderings. This is approximately an 8 percent reduction in residual shrinkage in the length dimension and a 63 percent reduction in the width dimension. The weight basis of the treated fabric also increased about 97 percent to 4.23 ounces per square yard. When further subjected to bleaching/dyeing, drying, and calendaring, the residual shrinkage for the same specimen was further reduced in the width dimension to about 6.5 percent in the length dimension and increased to about 6 percent in the width dimension. The weight basis decreased slight to 4.06 ounces per square yard. The increase in the width dimension and slight decrease in the weight basis are the result of the mechanical action of the calendaring process.
At the opposite end of the pressure/speed spectrum, a specimen of the same fabric construction was treated at a pressure of 25 bar and a line speed of 30 meters per minute. The residual shrinkage was reduced by the hydrodynamic treatment to about 10.8 percent in the length dimension and 7 percent in the width dimension. This is approximately a 29 percent reduction in residual shrinkage in the length dimension and a 43 percent reduction in the width dimension. The weight basis increased to 4.25 ounces per square yard. When further subjected to bleaching/dyeing, drying, and calendaring, the residual shrinkage for the same specimen was further reduced to about 4.7 percent in the length dimension and decreased to 5.9 percent in the width dimension. The weight basis remained unchanged.
As shown in FIG. 4 , at higher jet manifold pressures, higher line speeds may be used to obtain acceptable results. Conversely, at lower jet manifold pressures, lower line speeds are necessary to achieve similar results. Thus, any number of combinations of speeds of 120 meters per minute and pressures of between about 25 bar and 40 bar would provide results consistent with those described herein.
Additionally, as shown in FIG. 4 , the bursting strength of the tested greige fabric is 77.5 pounds as measured in accordance with Standard ASTM D 3787-01, Standard Test Method for Bursting Strength of Textiles—Constant-Rate-of-Traverse (CRT) Ball Burst Test. After subjecting the knitted fabric to the hydrodynamic treatment described herein, the fabric had a bursting strength between about 77 and 80, with an average bursting strength of about 78. Thus, the bursting strength of the hydrodynamically treated fabric is relatively unchanged, demonstrating that the hydrodynamic treatment does not degrade or weaken the fabric.
Referring again to FIG. 4 , the initial greige fabric has a measured resistance to pilling of 4/4 (front/back) after a first cycle and 3/3 after a second cycle when measured in accordance with Standard ASTM D 3512, Standard Test Method for Pilling Resistance and Other Related Surface Changes of Textile Fabrics: Random Tumble Pilling Tester. After subjecting the knitted fabric to the hydrodynamic treatment described herein, the measured resistance to pilling remains unchanged for the various combinations of pressure and line speed. Thus the hydrodynamically treated fabric is not more susceptible to pilling, and would not have a higher pill rate, as a result of the treatment, even though the hydrodynamic treatment has the effect of creating barbs, or hooks, on the surfaces of the yarns forming the fabric. Further, and as shown in FIG. 4 , subsequent bleaching or dyeing of the hydrodynamically treated fabric does not decrease the resistance of the dyed or bleached fabric to pilling.
Lastly, garments (T-shirts) formed from the tubular knitted fabric were subjected to repeated laundering up to five home laundering cycles in accordance with AATCC Test Method 135. The following measured residual shrinkage values were obtained:
25 bar
30 bar
35 bar
30 m/min
30 m/min
100 m/min
1 Wash
Length
3.3%
3.45%
5%
Width
5.3%
5.1%
5.9%
3 Washings
Length
5.8%
4.25%
5.8%
Width
5.3%
5.1%
5.9%
5 Washings
Length
6.7%
5.3%
7.5%
Width
5.3%
5.1%
5.9%
These results illustrate that garments formed from tubular knitted fabric that is treated and finished in accordance with the method described herein exhibit relatively low levels of residual shrinkage, a desired characteristic of finished retail apparel.
Although the present invention has been described with preferred embodiments, it is to be understood that modifications and variations may be utilized without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the appended claims and their equivalents. It should also be understood that terms used herein should be given their ordinary meaning to a person of ordinary skill in the art, unless specifically defined or limited in the application itself or in the ensuing prosecution with the Patent Office. | A method is provided for conditioning a tubular knitted fabric. The method includes the step of placing on a supported member a tubular knitted fabric formed of yarns, the yarns having fibers of a high cotton content. The layers of the fabric are arranged in overlying layered relation, each layer having an outer surface. The fabric is traversed at a preselected rate while subjecting the outer surfaces of the overlying layers to jets of fluid at pressures of about 40 bar absolute or lower. The fibers forming the overlying layers do not interlock the overlying layers and are separable by subsequent fabric finishing or laundering. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable.
FEDERALLY SPONSORED RESEARCH
Not applicable.
SEQUENCE LISTING, ETC ON CD
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to doctor blade systems for applying coatings in a printing or coating process, and in particular to a new design for the doctor blade head.
2. Description of Related Art
In the application of liquid substances to a moving web or successive sheets of material, it is considered well known in the art to apply the liquid using a rotating transfer roller, and to directly apply the liquid uniformly onto the roller by means of a doctor blade assembly. The doctor blade assembly generally includes a reservoir chamber extending the length of the transfer roller and in contact with the circumferential surface thereof, and a pair of doctor blades extending longitudinally on either side of the chamber. The doctor blades are angled obliquely toward the transfer roller surface, and serve both to seal the reservoir chamber to the roller and to form a uniform film of liquid on the roller transfer surface. The assembly also must include some means to seal the reservoir chamber at the ends of the roller, so that the liquid is not flung from the roller into the surroundings, and so that the liquid may be pumped through the reservoir during the transfer process. Such transfer systems are used in flexographic and gravure printing, adhesive applicators for substrates such as paper or plastic, coating applicators in many different industrial processes, and the like. Exemplary system are described in U.S. Pat. Nos. 4,821,672 and 6,576,059 issued to Nick Bruno.
It is apparent that the doctor blade head must provide uniform coating of the transfer roller to the utmost extent, so that the printed output is as perfect as possible. Factors that may cause defects in the liquid layer on the transfer roller may include the transfer roller itself, which is furnished with a micro-etched pattern designed to sustain the liquid film that is transferred to the printing or coating roller. The pattern may also carry air into the doctor blade cavity and cause bubbles to form in the coating liquid in the cavity, leading to defects in the coating and printing drop-outs in the final product. This effect is also exacerbated by the rotational velocity of the transfer roller and printing roller, and may limit the production speed of the printing press.
Indeed, the doctor blade cavity may be viewed as a closed space having fixed side and end wall, except for the rapidly and constantly moving side wall formed by the transfer roller engaged by the doctor blade head. In the prior art the cavity is typically a flattened rectangular chamber, and the fluid flow is end-to-end through the cavity. It is quite possible for turbulence to occur within the flowing liquid, which retards the flow rate and requires higher pumping pressure to maintain the fluid flow through the chamber. Turbulence may be increased by the motion of the transfer roller surface forming one side of the cavity, again limiting the speed of the printing press.
In addition to the issue of turbulence, the pump that provides the pressurized fluid to the cavity typically creates pulses of pressure, particularly since pneumatically operated piston pumps are easiest to use and maintain in a transfer coating machine. Instability in the fluid pressure may also contribute to turbulence in the fluid and an ultimate degradation in printing quality.
BRIEF SUMMARY OF THE INVENTION
The present invention generally comprises an improved doctor blade head for coating a transfer roller. The doctor blade head is provided with several salient features that enable a high velocity flow of coating liquid longitudinally through the doctor blade chamber, while requiring a lower overall fluid pressure across the chamber. Higher fluid flow rates through the chamber enables the chamber to be replenished with fresh fluid more often, and less air (foam) is introduced into the fluid from the anilox roller surface that moves across the doctor blade opening.
In one aspect, the chamber is configured as a quasi-cylindrical cavity that is more similar to a round pipe than prior art designs, thereby allowing fluid flow with less restrictions (resistance) than previous chamber cavity designs. The decreased resistance increases the fluid velocity and decreases the pump pressure required to move fluid through the cavity.
In a further aspect, the doctor blade head is provided with a check plate mounted in the inlet side of the chamber that allows fluid into the cavity from the cavity inlet that is connected to a pump, but does not let fluid back-flow out of the cavity through the inlet side. There is another check plate mounted in the outlet side of the chamber that allows fluid to flow out of the cavity but prevents fluid flow into the chamber from the outlet side. These check plates enable the system to maintain a very low and unchanging fluid pressure in the cavity of the chamber. They also keep the chamber cavity completely filled at all times of operation, not allowing air into the cavity from outside the chamber system, which can cause large starvation spots (dropouts) on the anilox roller.
The invention also provides an hydraulic accumulator for stabilizing the pump pressure that feeds the chamber. The hydraulic accumulator acts as a fluid pressure and fluid velocity balancing device, and includes a rolling diaphragm piston moving in a cylinder that is connected to the inlet fluid path, with a spring impinging on the piston. If there is a fluid pressure spike from the chamber supply pump, it enters the cylinder though the inlet manifold, and pushes the rolling diaphragm to move outwardly in the cylinder against the spring, thus storing the energy and fluid from that pressure spike. As the fluid pressure decreases from the pump and in the chamber cavity, in between strokes, the spring pushes the stored fluid into the chamber cavity so that the hydraulic accumulator releases that energy and fluid into the chamber. The result of this that pressure spikes are attenuated and pressure dropoffs are compensated, so that there is continuous fluid flow through the chamber at a very stable fluid pressure. As the supply pump delivers more or less fluid, the hydraulic accumulator keeps the fluid pressure stable, and the chamber cavity completely filled when used in conjunction with the check-plates.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective rear view of the doctor blade head of the invention, shown engaged with a transfer roller.
FIG. 2 is a partially cross-sectioned perspective view of the hydraulic accumulator of the invention.
FIG. 3 is a partially cross-sectioned perspective view of the doctor blade chamber outlet assembly of the invention.
FIGS. 4-6 are cross-sectional elevations of the hydraulic accumulator shown in FIG. 2 , depicting sequentially the operation of the accumulator.
FIGS. 7-9 are cross-sectional elevations of the outlet check plate assembly shown in FIG. 3 , depicting sequentially the operation of the outlet check plate.
FIG. 10A is a cross-sectional side elevation of a typical doctor blade head known in the prior art, and FIG. 10B is a cross-sectional side elevation of the doctor blade head of the invention.
FIG. 11 is an exploded view of the hydraulic accumulator of the invention, and
FIG. 12 is an exploded view of the outlet check plate assembly of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention generally comprises an improved doctor blade head for coating a transfer roller that delivers a high velocity flow of coating liquid longitudinally through the doctor blade chamber, while providing a lower, more stable fluid pressure across the chamber. As shown in FIG. 1 , the doctor blade head 20 generally includes a channel-like structure 21 having a central web portion 22 with a plurality of mounting brackets 23 for securing the doctor blade head to a supporting framework (not shown). The head 20 includes a longitudinally extending cavity 24 ( FIG. 10B ) that has a longitudinally extending opening 26 . A pair of doctor blades 27 are secured in opposed, parallel fashion adjacent to the opening 26 , and are disposed to impinge on a rotating transfer roller 28 , whereby a film of coating fluid is applied to the roller. The roller may comprise an anilox roller or the equivalent known in the prior art.
As shown in FIG. 1 , a fluid pump 30 has its output connected through tubing or hose to an inlet assembly 31 disposed at one end of the structure 21 , and the inlet of the pump is connected to an outlet manifold assembly 32 disposed at the other end of the structure 21 , so that fluid from the pump flows the length of the cavity 24 before returning to the pump.
A salient feature of the invention is an hydraulic accumulator 41 for stabilizing the pressure applied to the fluid in the doctor blade cavity 24 . The hydraulic accumulator 41 is located in the inlet assembly 31 , and is shown in FIGS. 2 , 4 - 6 , and 10 . With regard to FIGS. 2 and 10 , the hydraulic accumulator is comprised of an outer housing plate 42 and an inner housing plate 43 in stacked relationship and secured by bolts to the outer surface of the web 22 of channel-like structure 21 . The housing plates are provided with cylindrical recesses 44 and 47 that are equal in diameter and axially aligned to form a closed cylindrical space. A rolling diaphragm piston 52 is entrained between the opposed faces of the plates 42 and 43 , defining a variable volume fluid chamber 56 at the inner side and an outer chamber 44 that is open to ambient pressure. A spring 45 is seated in an annular groove 46 in the recess 44 to exert a resilient force to bias the piston 52 to extend into the recess 47 of plate 43 . A fluid passage 48 extends through the plate 42 and is connected at its outer end to a standard male connector 49 for a supply tubing extending to the pump outlet. Within the plate 43 a fluid passage 53 is aligned with and joins the passage 48 , the fluid passage extending to fluid chamber 56 .
The inner end of housing plate 43 is provided with a port 54 that communicates with the fluid chamber 56 . The port 54 also provides an annular seat 55 for an inlet check plate 51 , a flexible tongue that is shaped to occlude the port 54 . An inlet opening 57 is formed in the web 22 of doctor blade channel 21 in communication with the cavity 24 , the opening 57 providing a large area through which the fluid may pass so that locally generated turbulence is avoided. The opening 57 also provides space for the check plate 51 to deflect inwardly in a resilient fashion ( FIGS. 5 and 6 ) to allow fluid to enter the cavity 24 from the fluid chamber 56 . However, any retrograde flow from the cavity 24 toward the chamber 56 is blocked by the plate 51 urged to impinge on the seat 55 by the retro-flow as well as its own resilient restoring force. Thus if the input fluid pressure should falter for whatever reason, the check plate 51 prevents backflow out of the cavity 24 , an event that could, for example, potentially draw air into the system and cause starvation spots on the transfer roller.
Note that bolts are used to join the housing plates to the channel web 22 , along with appropriate seals to contain the fluid, but they are not enumerated herein.
The hydraulic accumulator 41 functions as shown in the sequence depicted in FIGS. 4-6 . When fluid from the pump enters the accumulator 41 from fitting 49 and passages 48 and 53 , the fluid flows into fluid chamber 56 , as shown in FIG. 4 . If there is a pressure spike in the fluid, it will overcome the force of spring 45 and cause the piston 52 to deflect ( FIG. 5 ) and enlarge the fluid chamber 56 , thus absorbing the pressure surge before it is transmitted to the cavity 24 . Note that the hydraulic accumulator does not interrupt the fluid flow to the cavity 24 , which continues as the check plate 51 is opened by the fluid flow advancing through port 54 and opening 57 into the cavity 24 . As the pressure spike passes, the piston 52 is urged by spring 45 to return inwardly, driving excess fluid from chamber 56 into the cavity 24 . The net result is that pressure spikes are attenuated, pressure dropoffs between pump strokes are compensated, and fluid pressure applied to the doctor blade cavity is stabilize to a high degree.
A further aspect of the invention, shown in FIGS. 3 , 7 - 9 , and 12 , is the provision of an outlet check plate in the outlet manifold assembly 32 . The web 22 is provided with an outlet opening 67 at the end that is longitudinally opposed to the inlet assembly, the outlet opening having sufficient area and smooth surface transitions to enable fluid flow therethrough without creating backpressure or turbulence in the cavity 24 . A rectangular housing 63 is secured to the web 22 , and the housing is provided with a chamber 64 extending therethrough. At the inner end of the housing 63 the chamber 64 is aligned in flow communications with outlet opening 67 . A check plate 61 is secured within the opening 67 , the check plate comprising a flexible tongue that is shaped to occlude the opening 67 . An annular seat 65 surrounds the opening 67 and is disposed to engage the check plate 61 in a manner similar to the seat 55 and check plate 51 , except that fluid flow is blocked if retrograde into the cavity 24 but free-flowing out of opening 67 . as shown in FIGS. 8 and 9 . At the outer end of the housing 63 a transparent window is secured and sealed at the opening of chamber 64 , providing a watch glass for visual inspection of the fluid outflow from the doctor blade chamber. A tapered end 68 protrudes from a lower side of the housing 63 , and a male tubing connector 69 extends therefrom to form a flow path from the outlet 67 past the check plate 61 and through the chamber 64 , thence out of the connector 69 to return to the pump 30 .
Note that the two check plates 51 and 61 act together to maintain the cavity 24 completely filled with fluid at all times, and enable the system to run at a very low fluid pressure in the cavity, while the hydraulic accumulator regulates and stabilizes the fluid pressure in the cavity.
Another important aspect of the invention is the shape of the cavity 24 of the doctor blade head 20 . With reference to FIG. 10A , a typical chambered doctor blade head known in the prior art is provided with a cavity 71 that is generally shaped as a flattened rectangle, with inlet and outlet connections 72 and 73 that open to the cavity in directions that are essentially transverse to the fluid flow along the longitudinal length of the cavity (parallel to the transfer roller axis). As a result turbulence may occur, requiring higher pump pressure and a wider opening between the doctor blades 77 in order to assure complete coating of the transfer roller surface.
In contrast with the prior art, the doctor blade head 20 of the invention ( FIG. 10B ) provides a cavity 24 that is configured as a quasi-cylindrical cavity that is more similar to a round pipe, thereby allowing a more streamline fluid flow with less restrictions (resistance) than previous chamber cavity designs. Note also that the opening 26 between the doctor blades 27 is substantially narrower than prior art devices; i.e., subtending an angle about the transfer roller axis that is as little as half the angle subtended by prior art devices ( FIG. 10A ). This reduction in contact area, made possible by the hydraulic accumulator 41 and check plates 51 and 61 , reduces vibration between the head and the roller and facilitates the application of a uniform coating.
The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and many modifications and variations are possible in light of the above teaching without deviating from the spirit and the scope of the invention. The embodiment described is selected 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 in various embodiments and with various modifications as suited to the particular purpose contemplated. It is intended that the scope of the invention be defined by the claims appended hereto. | A doctor blade head for coating a transfer roller includes a semi-cylindrical cavity to enable streamline fluid flow therethrough, and check plates at the inlet and outlet openings for permitting unidirectional flow into the inlet opening from said pump and out of the outlet opening toward the pump. An hydraulic accumulator acts as a fluid pressure and fluid velocity balancing device, and includes a rolling diaphragm piston moving in a cylinder that is connected to the inlet fluid path, with a spring impinging on the piston to absorb pressure surges and compensate pressure dropoffs. | 1 |
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