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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of provisional patent application Ser. No. 61/576,370 filed 2011 Dec. 16 by the present inventor.
BACKGROUND
Prior Art
The following is a tabulation of some prior art that presently appears relevant:
U.S. Pat. No.
Pat. No.
Issue Date
Patentee
4,344,351
Aug. 17, 1982
McQueen
4,514,923
May 07, 1985
Teel
4,685,379
Aug. 11, 1987
Troncoso
4,787,288
Nov. 29, 1988
Miller
5,074,190
Dec. 24, 1991
Troncoso
6,101,918
Aug. 15, 2000
Akins
6,966,138
Nov. 22, 2005
Deckard
Semi-automatic firearms have a limited firing rate as compared to automatic weapons. Automatic weapons are also known to be prohibitively expensive and harder to acquire than semi-automatic firearms. As a result many devices have been proposed in the past for increasing the firing rate of semi-automatic firearms. See for example, U.S. Pat. No. 4,344,351 to McQueen; U.S. Pat. No. 4,787,288 to Miller; U.S. Pat. Nos. 4,803,910 and 5,074,190 to Troncoso; U.S. Pat. No. 6,101,918 to Akins; and U.S. Pat. No. 6,966,138 to Deckard.
Some of these solutions attempt to make it easier to “bump fire”, or use the firearms recoil to allow user to manipulate trigger faster, but these solutions fail to meet the needs of the industry because of complicated non-intuitive operation or undesirable add on devices. Other solutions attempt to use mechanical means such as crank or slide devices to manipulate trigger quickly, but these solutions are similarly unable to meet the needs of the industry because non-intuitive operation with difficulty maintaining accurate fire. Still other solutions, for example U.S. Pat. No. 6,966,138 to Deckard, seek to convert a standard trigger to fire a shot on both pull and release, but these solutions also fail to meet industry needs because the device needs to be installed and removed to switch between modes of operation, and are not compatible with trigger systems with a forward hammer engagement surface such as AR-15 and AR-10 pattern rifles, one of the most popular rifles in the United States.
Deckard's device also has no means of eliminating the possibility of “hammer follow” in the double-fire mode. In the double fire mode, if the trigger is not manipulated properly, the hammer can follow the bolt assembly forward as it reciprocates resulting in either multiple rounds fired with one function of the trigger or the hammer being in a forward (fired) position with a loaded round in the chamber.
In the double fire mode of Deckard's device, the primary sear surface of the trigger and the disconnector engagement surface are spaced so that if the trigger is improperly manipulated or held in a central position, the hammer will not be held in a rearward position. The hammer will follow the bolt assembly forward, resulting in the aforementioned automatic fire or requiring manually reciprocating the bolt assembly to resume firing. This is a serious shortcoming of the device, as it is capable of firing more than one round with a single function of the trigger thus meeting the definition of a machine gun as described in 26 U.S.C. 5845(b), in which a machine gun is defined as a weapon which is able to fire more than one shot with a single function of the trigger. Thus this device would not gain approval by the Bureau of Alcohol, Tobacco, Firearms and Explosives Firearms Technology Branch for civilian sales.
Thus, the need exists for solutions to the above problems with prior art.
SUMMARY
The present invention is a selectable trigger for semiautomatic firearms, enabling quick and easy transitions between two modes and rates of fire. One mode allows normal semiautomatic operation, in which the firearm fires one round with a pull of the trigger and resets trigger with release of trigger, and another mode which fires a round with a pull of the trigger and fires another round with trigger release, thus doubling rate of fire.
In one embodiment the invention comprises of the following core components: A trigger, a primary disconnector, a secondary disconnector, a hammer, a selector cam, a selector lever, a detent spring and detent ball. These components are connected as follows: The selector cam is positioned under the front of the primary disconnector. The shaft of the selector cam passes through the trigger. The selector lever is fastened to the bottom of the selector cam by a cross pin. A spring and detent ball are located in the selector lever and engage voids in the trigger to keep selector lever in desired position.
When the selector lever is turned, the selector cam engages the primary disconnector, tilting the primary disconnector on its axis, thus varying the amount of engagement of the primary disconnector on the hammer.
With the selector in first position, the firearm will function as most semiautomatic firearms function, a pull of the trigger will fire one round, releasing the trigger will reset the trigger for the next shot. In this mode, the primary disconnector engagement will not release hammer until the engagement surface of trigger or trigger mechanism is in position to retain hammer in a cocked position.
With the selector in the second position, the firearm will fire one round when the trigger is pulled, and fire one round when trigger is released, thus doubling rate of fire. In this mode, the primary disconnector engagement depth is lessened, allowing the hammer to be released before the engagement surface of the trigger or trigger mechanism is in place to retain hammer in a cocked position, thus allowing hammer to fall striking firing pin, firing a round.
The secondary disconnector prevents the hammer from following the bolt assembly forward if the engagement surface of the trigger or the primary disconnector is not in position to retain hammer in a cocked rearward position. If the trigger is either forward or rearward the secondary disconnector will not engage the hammer, but if the trigger is in a central position that would allow the hammer to follow the bolt forward, the secondary disconnector will engage hammer retaining it in a rearward position until the trigger is either pulled or released.
Advantages
The present invention advantageously fills the aforementioned deficiencies by providing a selectable dual mode trigger for semiautomatic firearms which provides the user the ability to quickly and easily transition between two modes of operation, one mode doubling the rate of fire as opposed to a conventional trigger system. The invention requires no installation or removal of devices to transition between modes of operation, a simple flip of a switch is all that is required to transition between modes of operation.
The inventions secondary disconnector is advantageous in that the possibility of hammer follow is eliminated. The secondary disconnector greatly enhances the reliability of the trigger system, as well as prevents more than one round being fired per trigger function, thus meeting BATFE restrictions.
The invention is advantageous in that it is a mechanical device, and does not depend on the recoil of the weapon to function, as some prior art devices do. It will function equally well on firearms chambered for high or low recoil rounds.
The present invention is advantageous over prior art in that its operation in both modes is intuitive, with no unusual manipulations or motions required to operate. The device operates with a pull and a release of the trigger, in the same manner as practically every other firearm. The selector lever is unobtrusive, and does not hinder normal operation, handling, or function.
The present invention is advantageous in that it is compatible with trigger systems with a forward hammer engagement surface, such as the popular AR-15 and AR-10 pattern rifles or any semi-automatic firearm using or able to be adapted to use such a trigger system.
DRAWINGS
Figures
FIG. 1 shows the individual components of the invention in accordance with the first embodiment in a disassembled state.
FIG. 2 shows various aspects and details of the trigger, selector lever, detent, detent spring and selector cam.
FIG. 3 shows another aspect of the trigger, selector lever, and selector pin, showing the selector lever in the first position, allowing normal semi-automatic operation.
FIG. 4 shows another aspect of the trigger and selector lever with the selector lever in the second position, allowing a dual mode of fire with firearm firing one shot on trigger pull, and firing one shot on trigger release.
FIG. 5 shows various components of the invention in relation to the receiver or trigger housing of a firearm, with the trigger and selector lever protruding exposed allowing manipulation.
FIG. 6 shows another aspect, an underside view, of the trigger showing selector cam bore and recesses for detent engagement.
FIG. 7 shows the dual mode trigger in the forward position with the hammer in the cocked rearward position and the selector lever in the first position for normal semi-automatic operation.
FIG. 8 shows the dual mode trigger in rearward position with the hammer in the forward fired position and the selector lever in the first position for normal semi-automatic operation.
FIG. 9 shows the dual mode trigger in the rearward position with the hammer in rearward position with the hammer being held rearward by the primary disconnector and the selector lever in the first position to allow normal semi-automatic operation.
FIG. 10 shows the dual mode trigger returned to the forward position with the hammer in the cocked rearward position and the selector lever in the first position for normal semi-automatic operation.
FIG. 11 shows the dual mode trigger in the forward position with the hammer in the cocked rearward position and the selector lever in the second position to allow a shot to be fired both with trigger pull and trigger release.
FIG. 12 shows the dual mode trigger in the rearward position with the hammer in the forward fired position and the selector lever in the second position to allow a shot to be fired both with trigger pull and trigger release.
FIG. 13 shows the dual mode trigger in the rearward position with the hammer in the rearward position being held rearward by the primary disconnector and the selector lever in the second position to allow a shot to be fired both with trigger pull and trigger release.
FIG. 14 shows the dual mode trigger in the central position with the hammer in the forward fired position having been released by the primary disconnector and the selector lever in the second position to allow a shot to be fired both with trigger pull and trigger release.
FIG. 15 shows the dual mode trigger returned to the forward position with the hammer in the rearward cocked position and the selector lever in the second position to allow a shot to be fired both with trigger pull and trigger release.
FIG. 16 shows the dual mode trigger in the central position with the hammer in the rearward position being held rearward by the secondary disconnector and the selector lever in the second position to allow a shot to be fired both with trigger pull and release.
Drawings-Reference Numerals
1
trigger
2
hammer
3
primary disconnector
4
secondary disconnector
5
selector cam
6
selector lever
7
selector pin
8
selector detent
9
selector detent spring
10
secondary disconnector pin
11
primary disconnector spring
12
secondary disconnector spring
13
selector cam bore
14
hammer engagement surface of trigger
15
trigger engagement surface of hammer
16
hammer engagement surface of primary disconnector
17
primary disconnector engagement surface of hammer
18
hammer engagement surface of secondary disconnector
19
secondary disconnector engagement surface of hammer
20
raised camming surface of selector cam
21
safety selector (prior art)
22
second position selector detent recess
23
first position selector detent recess
24
hammer pin (prior art)
25
trigger and primary disconnector pin (prior art)
26
selector detent bore
DETAILED DESCRIPTION
FIGS. 1 - 16
Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
The core components of the selectable dual mode trigger are illustrated in FIG. 1 . A trigger 1 is manufactured with a selector cam bore 13 in which a selector cam 5 fits, with its shaft protruding from the bottom of the trigger 1 .
Affixed to the lower portion of selector cam 5 by means of a selector pin 7 is a selector lever 6 . A selector detent 8 and a selector detent spring 9 fit inside the selector lever 6 . The trigger 1 has a slot in its top portion to fit a primary disconnector 3 , a primary disconnector spring 11 , a secondary disconnector 4 , and a secondary disconnector spring 12 . A secondary disconnector pin 10 is used to retain the secondary disconnector 4 in the trigger 1 . A hammer 2 is equipped with engagement surfaces 15 , 17 , and 19 for the trigger 1 , primary disconnector 3 , and the secondary disconnector 4 respectively.
Alternative views of the trigger 1 , the selector lever 6 , and the selector cam 5 are shown in FIG. 2 . In this view, the top of the selector cam bore 13 is visible on the upper surface of the trigger 1 . This view shows a selector detent bore 26 in the top surface of the selector lever 6 in which the selector detent spring 9 and selector detent 8 fit. Three different aspect views of the selector cam 5 show in detail a raised camming surface 20 . The raised camming surface 20 interfaces with the primary disconnector 3 when the selector lever 6 is in the second position.
The selector lever 6 is shown in the first position in FIG. 3 . In this position, the firearm will function as a normal semi-automatic, firing one shot with trigger pull, and resetting trigger with trigger release. Also visible in FIG. 3 is the selector pin 7 .
The selector lever 6 is shown in the second position in FIG. 4 . The selector lever 6 rotates 90 degrees to transition between the two modes of fire. In the second position, the firearm will fire one round with trigger pull, and fire one round with trigger release. This mode of operation doubles the rate of fire as compared to normal semi-automatic operation.
In FIG. 5 various components of the selectable dual mode trigger are shown in relation to the firearms receiver or trigger housing. The curved portion of the trigger 1 and the selector lever 6 are exposed allowing manipulation to fire the weapon and to select between two modes of operation. The trigger 1 and the primary disconnector 3 pivot on a trigger and primary disconnector pin 25 . The hammer 2 pivots on a hammer pin 24 . A safety selector 21 serves as a static contact point for the secondary disconnector 4 during the firing cycle of the selectable dual mode trigger.
The underside of the trigger 1 is shown in FIG. 6 . Visible from this perspective are the selector cam bore 13 , a first position selector detent recess 23 , and a second position selector detent recess 22 .
OPERATION—FIGS. 7 - 16
FIG. 7 shows the selectable dual mode trigger cocked ready to fire. The selector lever 6 is placed in the first position to allow normal semi-automatic operation. The trigger 1 is in a forward position. The hammer 2 is retained in a cocked rearward position by the hammer engagement surface of the trigger 14 . The primary disconnector is pushed in a forward position by the primary disconnector spring 11 . The secondary disconnector 4 is pushed in a forward position by the secondary disconnector spring 12 . The secondary disconnector 4 is not contacting the safety selector 21 .
FIG. 8 shows the trigger 1 pulled rearward, disengaging the hammer engagement surface of the trigger 14 from the trigger engagement surface of the hammer 15 . This allows the hammer 2 to pivot forward, firing a round. The selector lever 6 is in the first position. The selector cam 5 is visible above the trigger 1 . The raised camming surface of the selector cam 20 is positioned beside the primary disconnector 3 . The secondary disconnector 4 is in contact with the safety selector 21 and is pivoted rearward.
FIG. 9 shows the trigger 1 in a rearward position being held there by the users finger immediately after a shot is fired. The selector lever 6 is in the first position. The hammer 2 has been returned to a rearward position by the firearms action, and is retained in that position by the primary disconnector 3 . The secondary disconnector 4 is in contact with the safety selector 21 and is in a rearward position.
FIG. 10 shows the trigger 1 released by the operator and returned to a forward position. The hammer 2 has been released by the primary disconnector 3 and is now being held in a cocked rearward position by the hammer engagement surface of the trigger 14 . The selector lever 6 is in the first position. The secondary disconnector 4 is in the forward position, no longer in contact with the safety selector 21 .
FIGS. 7-10 detail one cycle of the selectable dual mode trigger with the selector lever 6 in the first position. The firearm fired one round when the trigger 1 was pulled rearward by the operator, and the hammer 2 reset in a cocked rearward position when the operator released the trigger 1 . This is the normal semi-automatic mode of operation. The hammer 2 is in a cocked position ready to fire another round with the pull of the trigger 1 .
FIG. 11 shows the dual mode trigger with the trigger 1 in the forward position. The hammer 2 is in a cocked rearward position retained in that position by the hammer engagement surface of the trigger 14 . The selector lever 6 has been rotated 90 degrees and is now in the second position. The selector cam 5 has likewise rotated 90 degrees and the raised camming surface of the selector cam 20 is positioned under the front of the primary disconnector 3 . The raised camming surface of the selector cam 20 tilts the primary disconnector 3 rearward about 0.030″.
FIG. 12 shows the trigger 1 pulled rearward by the operator. The hammer 2 has rotated forward, firing a round. The selector lever 6 is in the second position. The primary disconnector 3 is tilted rearward about 0.030″ in relation to the trigger 1 . The secondary disconnector 4 is in contact with the safety selector 21 and is tilted rearward.
FIG. 13 shows the trigger 1 held in a rearward position by the operator immediately after firing a round. The hammer 2 has been returned to a rearward position by the firearms action and is retained in that rearward position by the primary disconnector 3 .
FIG. 14 shows the trigger 1 in a central position having been released by the operator. The selector lever 6 is in the second position and the primary disconnector 3 is tilted rearward about 0.030″ in relation to the trigger 1 . As a result of the primary disconnector 3 being tilted rearward by the raised camming surface of the selector cam 20 , the hammer engagement surface of the primary disconnector 16 is rearward about 0.030″ and releases the hammer 2 before the hammer engagement surface of the trigger 14 is in position to retain it in a rearward position. As a result, instead of the hammer 2 resetting as it does when the selector lever 6 is in the first position, the hammer 2 rotates forward firing a round. Thus, two rounds are fired in one rearward and forward cycle of the trigger 1 accomplishing a rate of fire double that of standard semi-automatic firearms.
FIG. 15 shows the trigger 1 released by the operator in the forward position. The selector lever 6 is in the second position. The hammer 2 has been returned to a rearward position by the action of the firearm. It is retained in the rearward cocked position by the hammer engagement surface of the trigger 14 . One rearward and forward (pull and release) cycle of the trigger 1 has now been completed resulting in the firing of two rounds, one shot on pull, one shot on release.
FIG. 16 illustrates the essential and novel function of the secondary disconnector 4 . When the selector lever 6 is in the second position, the primary disconnector 3 is tilted rearward about 0.030″ in relation to the trigger 1 . In this mode of operation, in which the firearm fires a round both with pull and release of trigger 1 , it is possible that neither the hammer engagement surface of the primary disconnector 16 or the hammer engagement surface of the trigger 14 will be in position to retain the hammer 2 when it is returned rearward by the firearms action. This possibility exists if the trigger 1 is in a central position, neither forward nor rearward completely.
In this scenario, the secondary disconnector 4 will retain the hammer 2 in a rearward position, preventing the hammer 2 from following the action or bolt forward. If the hammer 2 is retained in a rearward position by the secondary disconnector 4 , a complete pull or release of the trigger 1 will release the hammer 2 . If the trigger 1 is pulled to a rearward position, the secondary disconnector 4 will contact the safety selector 21 which tilts the secondary disconnector 4 rearward, causing the hammer engagement surface of the secondary disconnector 18 to disengage with the hammer 2 . The hammer 2 will then move forward slightly before being retained in a rearward position by the primary disconnector 3 as illustrated in FIG. 13 .
If the hammer 2 is retained in a rearward position by the secondary disconnector 4 as illustrated in FIG. 16 and the trigger 1 is released to a forward position by the operator, the secondary disconnector 4 will move rearward in relation to the hammer 2 and the hammer engagement surface of the secondary disconnector 18 will disengage the hammer 2 . The hammer 2 will then rotate forward slightly and be retained in a rearward position by the hammer engagement surface of the trigger 14 as illustrated in FIG. 15 .
In use, the operator chooses which mode of operation he desires to fire the weapon in and rotates the selector lever 6 accordingly. The operator then pulls and releases the trigger 1 . In the first mode the firearm will discharge one round with each complete pull and release of the trigger 1 , in the second mode the firearm will discharge two rounds with each complete pull and release of the trigger 1 .
The trigger 1 , hammer 2 , selector cam 5 , primary disconnector 3 , and secondary disconnector 4 are constructed of hardened firearms grade tool steel. The selector lever 6 can be constructed of various materials including but not limited to aluminum alloys, mild steel, hardened steel, or various composites.
While the invention has been described, disclosed, illustrated, and shown in one embodiment, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially if they fall within the scope of the claims here appended. Other embodiments could use other means of selectively varying the engagement of the primary disconnector such as a sliding or pivoting selector. The secondary disconnector could use a static point of contact other than the safety selector to accomplish disengagement with the hammer. Means other than a detent ball and spring could be implemented to secure the selector lever in the desired position. The invention can include additional features as desired, such as but not limited to a checkered, grooved or resilient surface on the selector lever.
ADVANTAGES
From the description above, a number of advantages of my selectable dual mode trigger for semiautomatic firearms become evident.
(a) The selector lever is unobtrusive and fits close to the receiver or trigger housing of the firearm.
(b) The selector lever allows easy transition between two modes and rates of fire without the addition or deletion of any devices or attachments.
(c) The selectable dual mode trigger can be installed in many firearms, such as AR-15 and AR-10 pattern rifles with no modification to the receiver or other major components of the firearm.
(d) The secondary disconnector retains the hammer in a rearward position if the trigger is in a central position, yet releases the hammer if the trigger is either pulled or released completely, preventing automatic fire or hammer follow malfunctions.
(e) The selectable dual mode trigger is mechanical and functions equally well on high or low recoil firearms, unlike many other devices for increasing rate of fire which are dependent on a firearms recoil to function.
(f) The selectable dual mode trigger is intuitive to use, the operator simply pulls and releases the trigger in both modes of fire, as in virtually every other firearm.
(g) The selectable dual mode trigger functions in both modes while the operator has a firm, natural grasp of the firearm which increases accuracy and control.
(h) Although other devices are add on and external, making them susceptible to damage and contamination with debris, the selectable dual mode trigger's components are contained inside the firearm thus increasing reliability and safety.
(i) The selectable dual mode trigger increases the rate of fire of a semiautomatic firearm without being classified as a machine gun or restricted weapon.
CONCLUSION, RAMIFICATIONS, AND SCOPE
Accordingly, the reader will see that the selectable dual mode trigger can be used to quickly and easily transition between two modes and rates of fire. The selectable dual mode trigger allows rates of fire approaching that of fully automatic firearms without the disadvantages of other proposed devices. Unlike other devices proposed to increase rate of fire, it is unobtrusive and requires no special techniques to operate. The selectable dual mode trigger is compatible with firearms and trigger systems with a forward hammer engagement surface, such as the popular AR-15 type firearms.
Although the description above contains many specificities, these should not be construed as limiting the scope of the embodiments, but providing illustrations of one embodiment. For example, the various components such as the trigger, hammer, disconnectors, selector lever and cam can have different shapes, the trigger can have a separate sear, the secondary disconnector can have alternative means of releasing hammer, etc.
Thus the scope of the embodiments should be determined by the appended claims and their legal equivalents, rather than by the examples given. | One embodiment of a trigger system with an integral selector for semi-automatic firearms. A selector allows the user to choose between two modes and rates of fire. A trigger ( 1 ) is made to allow passage of the lower portion of a selector cam ( 5 ) to the exterior of the firearm. A selector lever ( 6 ) is affixed to the lower end of the selector cam ( 5 ) on the exterior of the firearms action. Turning the selector lever ( 6 ) rotates the selector cam ( 5 ) which tilts a pivotal disconnector ( 3 ) on its axis, varying the amount of disconnector ( 3 ) engagement with a hammer ( 2 ). The variance in the disconnector ( 3 ) engagement causes the firearm to fire in one of two modes, firing one round with a trigger pull and resetting with trigger release, or firing one round with trigger pull, and firing another round with trigger release. Other embodiments are described. | 5 |
PRIORITY
[0001] This application claims priority of the Estonian national patent application number 201400004 filed on Feb. 4, 2014 the contents of which are incorporated herein by reference in entirety.
FIELD OF INVENTION
[0002] The invention belongs in the field of catering to the vital needs of people, specifically in the field of hygiene by means of disinfectants produced from aqueous solutions, especially from the aqueous solution of sodium chloride through electrolysis in a flow through diaphragm electrolyser. The invention provides a method for the production of disinfectants with active chlorine concentration in the range of 0-6000 ppm from a flow through diaphragm electrolyser, and at reducing the volume of the disinfectant for its transportation to the point of usage.
BACKGROUND
[0003] Electrolysis of the aqueous solution of sodium chloride in an anode compartment results in an anolyte that contains active chlorine compounds. An anolyte obtained with a prescribed concentration of active chlorine is a disinfectant that is widely used in various fields for disinfection and sterilisation.
[0004] The disinfectants that are normally used have the active chlorine concentration of not more than 500-800 ppm, and in case of production with diaphragm electrolysis, approximately 1500 g active chlorine is obtained per hour per one device. With the increase in the output of electrolysis devices by up to 8000 grams per hour, the opportunities for the application of the anolyte become wider in industrial technologies that require disinfectants with the active chlorine concentration of 2000-6000 ppm. Furthermore, the existence of high output electrolysis devices gave the possibility of centralised disinfectant production and delivery to consumers. In order to reduce transportation costs, the disinfectants with a high concentration of active chlorine became highly in demand.
[0005] A known method for the production of disinfectants with a high active chlorine concentration, whereby the chlorine is obtained from the electrolyser as gas which is then dissolved in water, such as chlorine dioxide, is provided in U.S. Pat. No. 7,833,392 [1]. The disadvantage of this method is that it requires higher safety precautions on account of leaking gas, and inadequate dissolution of the gas in water—less than 2.9 g/l.
[0006] U.S. Pat. No. 7,897,023 [2] describes a method for obtaining a mixture of oxidants from an electrolyser, mainly gaseous chlorine with the following dissolution in water. Besides the certain efficiency of this method, the disadvantage of this method is that it requires higher safety precautions due to leaking gaseous chlorine and the complexity of hydraulic connections for the production of large quantities of disinfectant, since the electrolyser on which the method [2] is based has low productivity—only about 40 grams of active chlorine per hour. This method [2] is also complicated due to the need to use a circulation circuit and special external heat exchangers for the cooling of electrolytes.
[0007] There are methods for the production of disinfectant in a liquid state by means of an electrolyser. Such disinfectants include the known sodium hypochlorite which is obtained through electrolysis. The methods for its production are not viewed, because sodium hypochlorite is obtained in another type of electrolyser—an electrolyser without a diaphragm, therefore the method for the production of sodium hypochlorite is not comparable with the method presented herein.
[0008] A method for the production of disinfectant with an electrolyser by means of sodium chloride electrolysis with the output capacity of more than 600 grams of active chlorine per hour is possible on the basis of the description of electrolyser provided in U.S. Pat. No. 8,298,383 [3]. The disadvantage of patent [3] is that the reduction of flows passing through the electrode compartment for the purpose of producing disinfectants with active chlorine concentration of up to 2000 ppm causes the electrodes to heat up to 100° C.
[0009] Patent GB 1396765 [4] describes a method for the production of disinfectant, wherein the heat of an anode as the inner electrode is lowered by passing coolant through a hollow inside the anode. The disadvantage of this method is its complexity due to the auxiliary external circulation circuit and a heat exchanger required for the cooling of the liquid.
[0010] Patent RU2350692 [5] describes a method, wherein the flow of electrolyte from the outside is channelled into a hollow in the anode, cooling it, and then flowing into the cathode compartment for producing the catholyte. The disadvantage of this method is that the method is not intended for the production of disinfectants and that the electrolyte enters the hollow in the anode from internal space through perforation in the anode wall, reducing the durability of the anode coating and the functioning order of the anode.
[0011] For the reduction of catholyte heating, the method of cooling by means of a Peltier element is also used in a known method (Thermoelectric Cooler—TEC), see e.g. patent JP2000051860 [6]. The disadvantage of this method is its low output caused by the low capacity of the Peltier element—up to 100 W/h, which allows taking out heat of no more than 4 litres per hour when producing disinfectants with active chlorine concentration of up to 6000 ppm.
[0012] In terms of embodiment and the achieved result, patent EE05608 [7] is the closest method, where the whole flow of water that passes into the electrolyser is initially divided into two parts: one part is guided into the cathode compartment, the second part is divided into two flows, one of which is guided into the anode compartment and the second flow is guided into an inner hollow in the cathode and then to the upper cover of the electrolyser for the purpose of diluting the anolyte to the required active chlorine concentration in the disinfectant, i.e. only part of the total water intended for the dilution of anolyte in the upper cover is guided to the cooling of the cathode. The active chlorine concentration in the anolyte before the anolyte reaches the upper cover of the electrolyser is up to 3000 ppm. This method [7] is regarded as the closest analogue. However, the disadvantage of this method, which was initially planned for the production of disinfectant at 500 ppm, is its limited capacity to yield disinfectants with high concentration, because the flow that is intended for the anode compartment enters the anode compartment, bypassing the inner hollow of the cathode, not participating in the cooling of the cathode and also not participating in the cooling of the catholyte, whereby the catholyte is only cooled by the flow that is intended for the reduction of active chlorine concentration in the disinfectant of less than 3000 ppm. However, with the need for production of disinfectants with active chlorine concentration of 3000 ppm, diluting the anolyte will no longer be necessary, i.e. the dilution flow that passes through the inner hollow of the cathode is stopped and only 2 flows will pass through the electrolyser: one flow through the cathode compartment, the other flow through the anode compartment, and method [7] becomes method [3] with a disadvantage that is related to the heating of electrolytes in the electrode compartments. As a result, application of method [7] in practice yields disinfectants with active chlorine concentration of no more than 2000 ppm, or cooling circulation circuits were to be used in order to obtain higher concentrations.
SUMMARY OF THE INVENTION
[0013] The objective of the invention is to extend the range of active chlorine concentration in the disinfectant and to produce disinfectants with adjustable active chlorine concentration from 0 to 6000 ppm with a simple method by means of a diaphragm electrolyser, without using external cooling circulation circuits and Peltier elements.
[0014] The objective is solved on account of the method for the production of disinfectants with a diaphragm electrolyser, which includes the formation of flow through a cathode compartment, as it foresees branching only a very small portion of fresh water through an inner hollow of the cathode, whereas the following differences have been planned:
the whole volume of water for the formation of flow in the anode compartment passes initially through the inner hollow of the cathode; the flow rate through the anode compartment shall not be less than 3.3 litres per hour per anode compartment at electric power 100 W/h, which in the viewed examples accounts for 4 litres per hour per 1 dm 2 of anode surface facing the cathode.
[0017] In the presented method, the causal relations between the achieved results and flow directions and volumes have been reached. In the viewed examples the entire flow that is intended for the formation of flow is passed through the anode compartment, the inner hollow of the cathode, whereas the volume of flow through the inner hollow of the cathode is not less than 4 litres per hour calculated per 1 dm 2 of the anode surface facing the cathode, while the volume of flow guided to the anode compartment also accounts for not less than 4 litres per hour per 1 dm 2 of the anode surface facing the cathode. These characteristics of the method are related to the operating conditions of the electrolyser: low volume of flow through the cathode compartment, difficulties in the heat exchange due to the diaphragm between the anode and cathode compartments (the presented method was tested, using a ceramic diaphragm), the method employs operating voltage not exceeding 24 A per 1 dm 2 and is not destructive for the protective coating of the anode surface facing the cathode. The voltage between the electrodes does not exceed 10 V. As an example of the calculation, an electrolyser is viewed where the area of anode surface is 1 dm 2 . Anolyte from the sodium chloride solution flows through the anode compartment into fresh water at 4 litres per hour, almost 15 g/l. Catholyte flows from the fresh water through the cathode compartment at 0.16 litres per hour. This catholyte is the alkali sodium hydroxide in which fresh water was generated during the electrolysis, flowing through the inner hollow of the cathode at 4 litres per hour.
[0018] Since the electric conductivity of the flows through the anode compartment and through the cathode compartment is approximately the same, the distance from the anode to the diaphragm and the distance from the cathode to the diaphragm is approximately the same, and the voltage drop in both compartments can be 5 V at maximum, the current used in the calculation is 24 A. If there was no flow passing through the inner hollow of the cathode, the temperature of the catholyte at the flow rate of 0.16 litres per hour could increase within 1 hour to:
[0000]
5
V
×
24
A
×
3600
sec
4187
g
/
l
×
0.161
=
644.8
°
C
.
[0019] In other words, the catholyte would start boiling, 7 minutes in this example. However, in 7 minutes the catholyte actually heats up to 45° C., therefore, in connection with the high electric conductivity of the metal wall of the cathode, the heat from 120 W/h transfers not only to the catholyte at the rate of 0.16 litres per hour, but also to the flow 4 litres per hour through the inner hollow of the cathode. In a case of ideal thermal conductivity of the cathode wall, the temperature of the cathode should increase to 24.8° C. In the actual process of disinfectant production the catholyte initially heats up by 45° C. in comparison with the initial temperature of fresh water; the fresh water in the inner hollow of the cathode heats up by 16° C. The water from the inner hollow of the cathode is guided to mixing with sodium chloride, and the sodium chloride solution is guided to the anode compartment, where the solution is heated up by further 25.8° C., i.e. the calculated temperature of the solution in the anode compartment exceeds the initial temperature of water by 40.8° C. Actually, the temperature of the solution discharged from the anode compartment exceeds the initial temperature of water by less than 35° C., because in the actual process of method embodiment the heat is transmitted into the ambient environment through the metal wall of the anode. The flow of fresh water through the inner hollow of the cathode is necessary primarily during the first operating hour of the electrolyser until the diaphragm has gained supplementary heat conductivity.
[0020] The diaphragm, which has become completely wet, allows the anolyte to be involved in the cooling of the catholyte. At the current of 24 A per 1 dm 2 of the anode surface facing the cathode, every 4 litres per hour of sodium chloride solution yields anolyte at 4 litres per hour, which contains no less than 24 grams of active chlorine, i.e. producing a disinfectant with the active chlorine concentration of not less than 6000 ppm. In order to prevent further heating of electrolytes, the current passing through the anode compartment is 100 W/h, not less than 3.3 litres per hour per anode compartment, and the current passing through the cathode compartment is 100 W/h, not less than 0.13 litres per hour per cathode compartment.
[0021] Thereby, the presented method has the following important features:
[0000] 1) the whole flow of water intended for the formation of flow through the anode compartment and the whole flow that is necessary for the dilution of anolyte to a concentration below 6000 ppm is guided to the inner hollow of the cathode;
2) the rate of anolyte flow through the anode compartment by not less than 3.3 litres per hour at converted electric energy of 100 W/h applied in the anode compartment, and the rate of catholyte flow through the cathode compartment by not less than 0.13 litres per hour at converted electric energy of 100 W/h applied in the cathode compartment, are required and sufficient for the achievement of technical results for extending the range of active chlorine concentration in disinfectants to up to 6000 ppm and for producing disinfectants with active chlorine concentration of 6000 ppm in an acceptable heat schedule without using any cooling circulation circuits and Peltier elements.
[0022] The invention in the presented method allows extending the range of active chlorine concentration in disinfectants of 0-2000 ppm from the concentration of the closest analogue to the concentration of 0-6000 ppm, and reduces the volume of the disinfectant for its transportation to the point of usage.
SHORT DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 provides a chart of the method for the production of disinfectants with a diaphragm electrolyser.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Referring to FIG. 1 : The initial fresh water flow 1 is divided into two flows by means of a T-piece 2 through which fresh water flow 3 is guided into cathode compartment 4 , while fresh water flow 5 is guided into an inner hollow 6 inside cathode 7 . From the inner hollow 6 the flow 5 is guided into T-piece 8 that divides the flow 5 into two flows of which fresh water flow 9 is guided to the upper cover 10 of the electrolyser for the purpose of mixing with anolyte 11 that arises through the anolyte compartment 12 to the upper cover 10 , while fresh water flow 13 is guided into mixer 14 , where flow 13 is mixed with the flow of concentrated sodium chloride solution 15 . After the mixer 14 the electrolyte flow 16 in the form of sodium chloride solution is guided into anode compartment 12 .
[0025] The rate of flow 9 is adjusted by means of regulator 17 , the rate of flow 13 is adjusted by means of regulator 18 , and the rate of the flow of concentrated sodium chloride solution 15 is adjusted by means of regulator 19 . Regulators 17 , 18 , 19 can be typical attachments: valves, dampers, dispenser pumps, etc. When the volume of electrolyte 16 that passes through anode compartment 12 is not less than 3.3 litres per hour at electric power 100 W/h per anode compartment, then at sufficient electric power the electrolyte 16 becomes anolyte 11 with the active chlorine concentration of 6000 ppm, which at such concentration is a ready disinfectant 20 and at this point the flow 9 is not used, or in case of producing a disinfectant with the active chlorine concentration of less than 6000 ppm, the anolyte is mixed in the upper cover 10 with the fresh water coming from flow 9 . The pH of the disinfectant is adjusted similarly to flow 3 in the method of the method of [7], where it is guided to cathode compartment 12 due to changes in mineralisation. The figure presents a version where the solution of concentrated sodium chloride is added to fresh water flow 3 by means of T-piece 21 and regulator 22 of the volume of sodium chloride solution.
[0026] The products of the electrolysis in the form of catholyte 23 and hydrogen 24 in cathode compartment 12 are discharged for disposal.
[0027] Thereby FIG. 1 illustrates how in the embodiment of the presented method the catholyte flow 4 is protected against overheating by means of fresh water flow 5 , which always flows through the inner hollow of cathode 7 , cooling down catholyte 4 , and the amount of which is at least equal with the amount of anolyte 11 .
[0028] The results of tests conducted with the presented method confirm the functioning of the method and are presented in the table below.
[0000]
TABLE
Temperature of disinfectant and catholyte in the presented method
at initial water temperature 12° C.
Temperature ° C. after
Concentration of active
120 minutes of electrolysis
chlorine in the disinfectant
disinfectant
catholyte
500 ppm
16
14
2000 ppm
22
20
3000 ppm
25
23
6000 ppm
42
40 | A method for production of disinfectant with active chlorine concentration in the range 0-6000 ppm from a flow through diaphragm-electrolyser with one of the aims to reduce the volume of disinfectant for its transportation to the point of usage. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. Ser. No. 13/781,200, filed Feb. 28, 2013, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an improved anchoring arrangement for use in conjunction with building construction having a masonry wall secured to steel building column supports. More particularly, the invention relates to construction accessory devices, namely, specially-configured hook column anchors with laser carve-outs that provide high strength pullout resistance when secured to the columns and within the masonry wall bed joints. The invention is applicable to structures having walls constructed from brick, block or stone in combination with a building column support.
[0004] 2. Description of the Prior Art
[0005] In the past, investigations relating to the effects of various forces, particularly lateral forces, upon brick veneer masonry construction demonstrated the advantages of having high-strength anchoring components embedded in the bed joints of anchored walls, such as facing brick, block or stone wall. Anchors are generally placed in one of the following five categories: corrugated; sheet metal; wire; two-piece adjustable; or joint reinforcing. The present invention has a focus on sheet metal and in particular, single construct hook column anchors for wall construction having steel column supports.
[0006] The use of steel for the construction of building wall supports has become increasingly popular since its inception in the late 1800s. In the 1940s, veneer construction with steel frames was introduced and its popularity has grown steadily since its introduction. This popularity results from the inherent benefits of steel, as opposed to masonry or wood construction. Steel is one of the strongest building frame materials available and is significantly safer, in that it is not susceptible to insect infestation, rotting or destruction from fire. The high strength of a steel structure provides greater resiliency against the effects of aggressive weather. Steel structures are also more cost effective, providing ease of construction and transport and requiring less material than timber or block methods. Steel is an environmentally-friendly construction material because it is recyclable and results in less raw material waste.
[0007] Laser cutting of the column anchor is performed by directing the output of a high-power laser, by computer, to melt, burn, or vaporize the desired configuration of the apertures and cut-outs. Examples of lasers used in the laser cutting herein include, but are not limited to, the CO 2 laser (and its variants), and the neodymium and neodymium yttrium-aluminium-garnet laser. Laser carving provides the ability to make the detailed carve-outs in the high-strength metals to form the presently presented column anchors without altering the metal structural attributes. Laser cutting provides advantages over mechanical cutting or plasma cutting because the workholding is easier and there is reduced contamination of the workpiece (there is no cutting edge). Precision is also improved because there is no wear of the cutting edge in the process and the structural integrity of the high-strength metal is uncompromised.
[0008] Anchoring systems for wall construction come in varied forms depending on the wall materials and structural use. Ronald P. Hohmann and Hohmann & Barnard, Inc., now a MiTek-Berkshire Hathaway company, have successfully commercialized numerous devices to secure wall structures, providing improvements that include increases in interconnection strength, ease of manufacture and use, and thermal isolation. The present invention is an improvement in interconnection strength and increased pullout prevention from both the masonry wall and the steel columns.
[0009] The high-strength laser configured column anchors of this invention are specially designed to prevent anchor pullout from the masonry wall and the building column support. The configured anchors restrict movement and ensure a high-strength connection and transfer of forces between the steel columns and masonry wall. The column anchor insertion portion is laser configured to ensure full mortar coverage when disposed within the masonry wall bed joint, restricting anchor pullout, while maintaining the requirements for mortar tolerances set forth in the Building Code Requirements for Masonry Structures, Chapter 6, Veneer. The close control of the overall dimensions of the insertion portion permits the mortar of the bed joints to flow through, over and about the anchor to secure against the laser configurations. The anchor hereof employs extra strong material and benefits from the laser configuration of the metal, providing an anchoring system that meets the unusual requirements demanded in current building structures.
[0010] There have been significant shifts in public sector building specifications which have resulted in architects and architectural engineers requiring larger and larger spacing between the structural walls of public buildings. These requirements are imposed without corresponding decreases in wind shear and seismic resistance levels or increases in mortar bed joint height. Thus, the wall anchors needed are restricted to occupying the same ⅜-inch bed joint height in the masonry wall. Because of this, the masonry wall material is tied down over a span of two or more times that which had previously been experienced. Exemplary of the public sector building specification is that of the Energy Code Requirement, Boston, Mass. (See Chapter 13 of 780 CMR, Seventh Edition). This Code sets forth insulation R-values well in excess of prior editions and evokes an engineering response opting for thicker insulation and correspondingly larger cavities.
[0011] The use of anchors in wall construction have been limited by the mortar layer thicknesses which, in turn are dictated either by the new building specifications or by pre-existing conditions, e.g., matching during renovations or additions the existing mortar layer thickness. While arguments have been made for increasing the number of the fine-wire anchors per unit area of the facing layer, architects and architectural engineers have favored wire formative anchors of sturdier wire. On the other hand, contractors find that heavy wire anchors, with diameters approaching the mortar layer height specification, frequently result in misalignment. Thus, these contractors look towards substituting thinner gage wire formatives, which result in easier alignment of courses of block to protect against wythe separation. A balancing of mortar and wall anchor dimensions must be struck to ensure wall anchor stability within the masonry wall. The present high strength column anchor greatly assists in maintaining this balance in the mortar joint. The presently presented column anchor provides the required high-strength interconnection within the allowed tolerances.
[0012] Besides earthquake protection requiring high-strength anchoring systems, the failure of several high-rise buildings to withstand wind and other lateral forces has resulted in the promulgation of more stringent Uniform Building Code provisions. This high-strength laser configured wall anchor is a partial response thereto. The inventor's related anchoring system products have become widely accepted in the industry.
[0013] The following patents are believed to be relevant and are disclosed as being known to the inventor hereof:
[0000]
U.S. Pat. No.
Inventor
Issue Date
4,021,990
Schwalberg
May 10, 1977
4,473,984
Lopez
Oct. 2, 1984
4,598,518
Hohmann
Jul. 8, 1986
4,875,319
Hohmann
Oct. 24, 1989
6,298,630
VeRost, et al.
Oct. 9, 2001
6,739,105
Fleming
May 25, 2004
7,171,788
Bronner
Feb. 6, 2007
[0014] U.S. Pat. No. 4,021,990—B. J. Schwalberg—Issued May 10, 1977 Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. The wall tie is embedded in the exterior wythe and is not attached to a straight wire run.
[0015] U.S. Pat. No. 4,473,984—Lopez—Issued Oct. 2, 1984 Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation.
[0016] U.S. Pat. No. 4,598,518—R. Hohmann—Issued Jul. 7, 1986 Discloses a dry wall construction system with wallboard attached to the face of studs which, in turn, are attached to an inner masonry wythe. Insulation is disposed between the webs of adjacent studs.
[0017] U.S. Pat. No. 4,879,319—R. Hohmann—Issued Oct. 24, 1989 Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run.
[0018] U.S. Pat. No. 6,298,630—VeRost, et al.—Issued Oct. 9, 2001 Discloses a wall plate for attaching a horizontal or sloping beam to a vertical masonry wall. The wall plate is attached through the use of an anchor affixed to a steel beam. A method of attaching a horizontal or sloping beam to a vertical masonry wall is further disclosed.
[0019] U.S. Pat. No. 6,739,105—Fleming—Issued May 25, 2004 Discloses a construction assembly which includes a structure panel, with structural members and integrally molded insulation, a floor support, joists and a horizontal ledge. The assembly further includes cut-out tabs and wall anchors and ties interconnected therewith and secured to the assembly.
[0020] U.S. Pat. No. 7,171,788—Bronner—Issued Feb. 6, 2007 Discloses masonry connectors for embedment in masonry wall mortar beds and interconnection with a vertical sliding rail attached to a steel frame. The device, when installed, is designed to be embedded in mortar along the cross ribs of the masonry block and does not require grouting in the cells of the masonry units.
[0021] None of the above anchors or anchoring systems provides a laser configured column wall anchor with enhanced interconnection properties and pullout resistance. This invention relates to an improved anchoring arrangement for use in conjunction with building construction having a masonry wall secured to a steel building column support and meets the heretofore unmet need described above.
SUMMARY
[0022] In general terms, the invention disclosed hereby is a laser configured hook column anchor and anchoring system for use in anchoring a masonry wall to a steel column structure. The system includes a specially-configured laser-cut metal column anchor that provides high-strength interconnection and superior pullout resistance when embedded in mortar within the bed joint of the masonry wall and attached to the building column flange. The column anchor is designed to fill no more than one half the height of the bed joint to ensure construction in accordance with the applicable engineering standards and guidelines. The close control of overall heights permits the mortar of the bed joints to flow over and through the column anchors. The hook attachment portion resists detachment from the building column support structure and limits movement along the x- and z-axes.
[0023] In this invention, the column anchor is constructed from steel or similar high-strength material. In the first embodiment, the hook column anchor is a device with a hook attachment portion and laser carve-outs and edging along the insertion portion. The column anchor is affixed to the steel column flange and inserted in the bed joint of the masonry wall. The masonry block cells and bed joint are filled with mortar, completely surrounding the insertion portion of the column anchor. The column anchor of this embodiment may be fashioned for use as a right-sided or left-sided anchor and is for use either as a single anchor affixed to one of edge of the flange or in conjunction with a second anchor, providing attachments to both edges of the column flange.
[0024] The second embodiment includes column anchors similar to the first, but provides a slot in the attachment portion for interconnection with a clamp, when a single column anchor is employed, and a securement bar, when two column anchors are secured to the column flanges. Affixing hardware is employed to further secure the clamp and the bar to the column anchor(s).
[0025] It is an object of the present invention to provide in an anchoring system having a masonry wall anchored to a steel column support construct, a high-strength column anchor, which includes a laser configured insertion portion and a hook attachment portion.
[0026] It is another object of the present invention to provide a specialized column anchor that is configured to provide a high-strength interlock between the steel columns and the adjacent wall.
[0027] It is another object of the present invention to provide labor-saving devices to simplify installations of brick, block and stone walls and the securement thereof to a steel column support structure.
[0028] It is a further object of the present invention to provide an anchoring system for a wall comprising a single component that is economical to manufacture resulting in a relatively low unit cost.
[0029] It is a feature of the present invention that when the column anchor is installed within the masonry wall bed joint and the bed joint mortar surrounds the laser configurations and apertures, the column anchor provides high strength pullout resistance from the wall.
[0030] It is a further feature of the present invention that when the column anchor is affixed to the column flange, the hook attachment portion resists detachment along the x- and z-axes, while allowing movement along the y-axis.
[0031] It is another feature of the present invention that the column anchors are utilizable with a wall of masonry block having aligned or unaligned bed joints.
[0032] It is yet another feature of the present invention that the column anchor provides a high-strength interconnection within the allowable tolerances for mortar joint anchoring systems.
[0033] Other objects and features of the invention will become apparent upon review of the drawings and the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] In the following drawings, the same parts in the various views are afforded the same reference designators.
[0035] FIG. 1 is a perspective view of the first embodiment of the hook column anchor and anchoring system having two column anchors with laser configured insertion portions emplaced in the bed joint of the adjacent masonry wall and secured to a steel column support structure;
[0036] FIG. 2 is a perspective view of the left-sided column anchor of FIG. 1 ;
[0037] FIG. 3 is a partial cross-sectional view of the anchoring system of FIG. 1 on a substantially vertical plane showing one of the column anchors embedded in the masonry wall bed joint;
[0038] FIG. 4 is a partial perspective of the hook column anchor and anchoring system having a single column anchor with a laser configured insertion portion emplaced in the masonry wall bed joint and secured to a steel column support structure;
[0039] FIG. 5 is a perspective view of the column anchor of FIG. 1 with a right-sided orientation;
[0040] FIG. 6 is a partial perspective view of the second embodiment of the column anchor and anchoring system having a single column anchor with a laser configured insertion portion emplaced in the masonry wall bed joint and secured to a steel column support structure, the column anchor includes a clamp and affixing hardware;
[0041] FIG. 7 is an exploded perspective view of the column anchor and clamp of FIG. 6 ;
[0042] FIG. 8 is a perspective view of the anchoring system of FIG. 6 having two column anchors joined together by a securement bar and attaching hardware; and,
[0043] FIG. 9 is a perspective view of an alternative design column anchor of this invention having multiple apertures within the insertion portion.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] In the embodiments described herein, the column anchors are laser configured to have a thickness of no greater than one-half the bed joint height in the masonry wall, thereby becoming better suited to building structures requiring greater pullout resistance when secured within a masonry wall anchored to adjacent building columns. It has been found that the laser configured column anchors, once secured within the mortar joints of the wall and to the column flange, provide a superior interconnect between the wall and the adjacent building column support than the prior art. Before proceeding to the detailed description, the following definitions are provided. For purposes of defining the invention at hand, a volumetric construction unit (“VCU”) is a masonry unit constructed with mortar joints between each adjacent unit. A VCU includes, but is not limited to, masonry blocks, bricks, stone or similar material. Further, a building column is a high strength column or beam constructed of steel or similar material and positioned in an orientation that provides an “H” shape with a set of flanges and an interior web parallel to the face plane of the wall interconnecting the flanges.
[0045] The description which follows is of two embodiments of column anchors and anchoring systems utilizing the laser configured column anchor devices of this invention, which devices are suitable for various wall applications. Although each column anchor is adaptable to varied backup structures, the embodiments here apply to walls constructed with VCUs anchored to a building column support structure. For the masonry structures, mortar bed joint thickness is at least twice the thickness of the embedded anchor.
[0046] In accordance, with the Building Code Requirements for Masonry Structures, ACI 530-05/ASCE 5-05/TMS 402-05, Chapter 6, each structure forming the wall is designed to resist individually the effects of the loads imposed thereupon. Further, the outer masonry wall is designed and detailed to accommodate differential movement and to distribute all external applied loads through the wall to the adjacent building columns utilizing the column anchors.
[0047] Referring now to FIGS. 1 through 5 , the first embodiment of the laser configured column anchors and anchoring system of this invention is shown and is referred to generally by the number 10 . In this embodiment, a wall structure 12 is shown having a building column support structure 14 of building columns 16 and an adjacent wall 18 of VCUs 20 . The column structure 14 and the wall 18 are spaced apart by a predetermined space 22 , which extends outwardly from the surface 24 of the building column structure 14 . Optionally, the space 22 accommodates fireproofing (not shown) which is usually sprayed onto the building columns. Each of the building columns 16 has a flange 17 disposed on a central web 19 proximal to the wall 18 . The central web 19 is disposed substantially parallel to the face plane of the wall 18 . The central web 19 separates and joins the two substantially parallel flanges 17 .
[0048] In this embodiment, successive bed joints of mortar 30 and 32 are formed between VCUs 20 . Courses of VCUs 20 and the bed joints 30 and 32 are substantially planar and horizontally disposed. For each wall 18 , the bed joints 30 and 32 are specified as to the height or thickness of the mortar layer and such thickness specification is rigorously adhered to so as to provide the uniformity inherent in quality construction.
[0049] For purposes of discussion, the exterior surface 24 of the building column structure 14 contains a horizontal line or x-axis 34 and an intersecting vertical line or y-axis 36 . A horizontal line or z-axis 38 , normal to the xy-plane, also passes through the coordinate origin formed by the intersecting x- 34 and y-axes 36 . In the discussion which follows, it will be seen that the various anchors are constructed to restrict movement interfacially along the z-axis 38 and along the x-axis 34 . The device 10 includes a column anchor 40 constructed for attachment to the building column 16 and for embedment in bed joint 32 , which, in turn, includes an elongated plate member 42 with an insertion portion 54 and an attachment portion 56 .
[0050] The column anchor 40 is shown in FIGS. 1 and 5 as being emplaced on a course of VCUs 20 and embedded within the bed joint 32 in FIG. 3 . The elongated plate member 42 has a thickness of no greater than one-half of the bed joint 32 height and includes an insertion portion 54 with one or more apertures 60 therethrough to permit the mortar of the bed joint 32 to flow through and surround the elongated plate member 42 . A single aperture 60 is shown in this embodiment. Multiple apertures 160 are shown in FIG. 9 and are incorporated herein by reference as a design alternative. Opposite the insertion portion 54 , the elongated plate member 42 includes an attachment portion 56 , which anchors the wall 18 to the building columns 16 . The attachment portion 56 includes a hook portion 21 that surrounds the edge of the flange 17 and when so attached is substantially normal to the face plane of the wall 18 . A rotated portion 55 of the attachment portion 56 and is contiguous with the insertion portion 54 . The rotated portion 55 enables the insertion portion to maintain parallelism with the bed joint 32 . Either a single column anchor 40 (as shown in FIG. 4 ) or two column anchors 40 (as shown in FIG. 1 ) are secured to the building column 16 . When the mortar of the bed joint 32 surrounds the column anchor 40 , the mortar flows through the apertures 60 and provides strong interconnection and pullout resistance.
[0051] The elongated plate member 42 contains a peripheral edge portion 58 with a patterned edge portion 62 that is either regularly 64 or irregularly 66 patterned. An example of a regularly 64 patterned edge portion is shown in FIG. 2 as a saw tooth pattern 68 . For enhanced holding, the patterned edge portions 62 are, upon installation, substantially parallel to x-axis 34 . This relationship minimizes the movement of the construct in and along a z-vector and in an xz-plane.
[0052] The column anchor 40 is a plate-like device constructed from mill galvanized, hot-dip galvanized, stainless steel or other similar high-strength material. The column anchors 40 are specially designed and laser configured to have a thickness of no greater than one-half the bed joint height 32 in the wall 18 so when inserted within the bed joint 32 , the bed joint mortar surrounds the column anchor 40 filling the apertures 60 and the patterned edge portions 62 , providing superior pullout resistance and providing a superior interconnect between the wall 18 and the adjacent building column 16 . The hook portion 21 provides further pullout resistance from the columns 16 . When the VCUs 20 are masonry blocks with open cells 70 , additional mortar or grout fills the cells 70 ensuring even greater pullout resistance and interconnection with the wall 18 . In this embodiment, the column anchors 40 either have a right-sided orientation (as shown in FIG. 5 ) or a left-sided orientation (as shown in FIG. 2 ) for use on either proximal flange 17 allowing for flexibility in design and for multiple column anchor attachments.
[0053] The description which follows is of a second embodiment of the laser configured column anchor and high-strength anchoring system. For ease of comprehension, where similar parts are used reference designators “100” units higher are employed. Thus, the column anchor 140 of the second embodiment is analogous to the column anchor 40 of the first embodiment.
[0054] Referring now to FIGS. 3 , and 6 through 9 , the second embodiment of the high-strength column anchor and anchoring system is shown and is referred to generally by the numeral 110 . In this embodiment, a wall structure 112 is shown having a building column support structure 114 of building columns 116 and an adjacent wall 118 of VCUs 120 . The building column structure 114 is shown spaced from the wall 118 . The surface 124 of the building column structure 114 lies substantially in a plane parallel to that of the adjacent surface of wall 118 . Each of the building columns 116 has a flange 117 disposed on a central web 119 proximal to the wall 118 . The central web 119 is disposed substantially parallel to the face plane of the wall 118 . The central web 119 separates and is joined to the two substantially parallel flanges 117 .
[0055] In this embodiment, successive bed joints of mortar 130 and 132 are formed between VCUs 120 . Courses of VCUs 120 and the bed joints 130 and 132 are substantially planar and horizontally disposed. For each wall 118 , the bed joints 130 and 132 are specified as to the height or thickness of the mortar layer and such thickness specification is rigorously adhered to so as to provide the uniformity inherent in quality construction.
[0056] For purposes of discussion, the exterior surface 124 of the building column structure 114 contains a horizontal line or x-axis 134 and an intersecting vertical line or y-axis 136 . A horizontal line or z-axis 138 , normal to the xy-plane, also passes through the coordinate origin formed by the intersecting x- and y-axes. In the discussion which follows, it will be seen that the various anchors are constructed to restrict movement interfacially along the z-axis and along the x-axis. The device 110 includes a column anchor 140 constructed for attachment to the building column 116 and for embedment in bed joint 132 , which, in turn, includes an elongated plate member 142 with an insertion portion 154 , a rotated portion 155 and an attachment portion 156 .
[0057] The column anchor 140 is shown in FIGS. 6 and 8 as being emplaced on a course of VCUs 120 and embedded within the bed joint 132 (as shown in FIG. 3 ). The elongated plate member 142 has a thickness of no greater than one-half of the bed joint 132 height and includes an insertion portion 154 with one or more apertures 160 therethrough to permit the mortar of the bed joint 132 to flow through and around the elongated plate member 142 . A rotated portion 155 is contiguous with the insertion portion 154 . The rotated portion 155 enables the insertion portion 154 to maintain parallelism with the bed joint 132 when attached to the column structure 114 . Opposite the insertion portion 154 and contiguous with the rotated portion 155 , the elongated plate member 142 further includes an attachment portion 156 which interengages with the building columns 116 . The attachment portion 156 is formed from the elongated plate member 142 and contains a hook portion 121 that surrounds the flange 117 and provides interengagement with the flange 117 . The hook portion 121 provides a secured attachment with the flange 117 and resists column anchor 140 pullout and movement along the x- and z-axes 134 , 138 . The attachment portion 156 further contains a slot 171 medial the elongated plate member 142 . When the mortar of the bed joint 132 surrounds the column anchor 140 , the mortar flows through the apertures 160 and provides a strong interconnect and high-pullout resistance from the wall 118 .
[0058] The elongated plate member 142 contains a peripheral edge portion 158 with a patterned edge portion 162 that is either regularly 164 or irregularly 166 patterned. An example of a regularly 164 patterned edge portion is shown in FIG. 7 as a saw tooth pattern 168 . For enhanced holding, the patterned edge portions 162 are, upon installation, substantially parallel to x-axis 134 . This relationship minimizes the movement of the construct in and along a z-vector and in an xz-plane.
[0059] The column anchor 140 is a plate-like device constructed from mill galvanized, hot-dip galvanized, stainless steel or other similar high-strength material. The column anchors 140 are specially designed and laser configured to have a thickness of no greater than one-half the bed joint height 132 of the wall 118 so when inserted within the bed joint 132 , the bed joint mortar surrounds the column anchor 140 and fills the apertures 160 and patterned edge portions 162 , providing superior pullout resistance and interconnection between the wall 118 and the adjacent building column 114 . When the VCUs 120 are masonry blocks with open cells 170 , the cells 170 are filled with additional mortar or grout, ensuring even greater pullout resistance and interconnection with the wall 118 .
[0060] For greater column anchor 140 securement against the flanges 117 , an L-shaped clamp 174 connects the column anchor 140 to the opposite flange through the slot 170 . The clamp 174 is a wire formative and secured to the column anchor 140 with attaching hardware 172 as shown in FIGS. 6 and 7 . The column anchor 140 has either a right-sided orientation (as shown in FIG. 6 ) or a left-sided orientation (as shown in FIG. 7 ) for use on either proximal flange 117 , allowing for flexibility in design and for multiple column anchors attachments. Alternatively, as shown in FIG. 8 , both left-sided and right-sided column anchors 140 are interconnected with the flanges 117 and secured with a securement bar 176 inserted through the column anchor slots 171 . The securement bar 176 is a wire formative threaded to accommodate previously described hardware 172 and secured to the column anchors 140 as shown in FIG. 8 .
[0061] The present invention provides a novel improvement for column anchors. The laser cutting of the column anchor maintains the high-strength and durability of the metal anchors while providing precision cuts that allow for flow through reception of the bed joint mortar, enhancing pullout resistance within the wall bed joints. The bed joint and cell mortar completely surround the column anchors within the bed joint, providing a solid interconnection within the wall. The hook shaped attachment portion provides additional pullout resistance from the column building support.
[0062] Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | A high-strength laser configured column anchor and anchoring system is disclosed. The high-strength column anchor provides high-strength pullout resistance when embedded within the wall bed joint. Specially-configured apertures, edging and dimension restrictions provide for flow-through mortar embedment within the wall bed joint. The edging provides irregular and regular patterns ensuring a secure fit within the bed joint. The column anchors include a hook attachment portion for secure attachment to the column flanges and optionally include a securement bar or clamp to further secure the column anchor to the column flanges. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a mat to be constructed of wood or wood products and to be used in vertically and horizontally lapped relation in order to form a roadway or platform mat upon soft ground.
2. Description of Related Art
Various different forms of board mat constructions heretofore have been provided such as those disclosed in U.S. Pat. Nos.: 1,970,037, 2,639,650, 2,652,753, 2,819,026, 2,912,909, 4,289,420, 4,462,712 and 4,600,336. However, these various different forms of mat constructions, in many instances, do not provide sufficient ground traction between the mat constructions and the underlying ground surface and between the upper surface of the mat construction and a vehicle moving thereover. Furthermore, these previously known mat constructions may not be readily mass produced at low cost and the spacing of multiple transverse members thereof spaced along the length of the mat require spacing jigs in order to effect mass production. In addition, many of these previously known forms of mat constructions require extensive cleaning after each usage on soft ground and are difficult to correctly assemble when laying down a mat construction.
SUMMARY OF THE INVENTION
The mat construction of the instant invention, basically, includes a single rectangular planar surface defining member and only a single pair of transverse logs or members secured to and extending transversely of the opposite ends of the surface defining member.
When forming a roadway or platform a plurality of mat constructions are disposed with their surface defining member uppermost and their transverse logs or members lowermost and other mat constructions of the roadway or platform are inverted and disposed beneath the first mentioned mat constructions.
All of the mat constructions are of the same length and width and the transverse logs or members each have a width slightly less than one-quarter the length of the corresponding surface defining member and are spaced apart slightly greater than one-half the length of the corresponding surface defining member.
The inverted members, with the surface defining member lowermost and the transverse logs or members uppermost are first laid upon the ground in end-to-end aligned relation and the other mat constructions are then disposed over the inverted mat constructions with the spacing between the transverse end logs or members of each of the upper mat constructions receiving therein the adjacent transverse logs or members of adjacent ends of inverted mat constructions and the spacing between the transverse end logs or members of each lower mat construction receiving therein the adjacent transverse end logs or members of adjacent ends of the upper mat constructions.
The main object of this invention is to provide a mat construction for use in forming a roadway or platform on soft ground with a minimum amount of expense, transportation costs, difficulty in assembling the individual mat constructions in order to form a roadway or platform and ease of removal of the mat constructions after usage and cleaning thereof prior to subsequent usage.
Another object of this invention is to provide a mat construction in accordance with the preceding objects which will afford ground traction between the lower mat constructions and the ground upon which they are disposed.
Another object of this invention is to provide mat constructions formed in a manner such that surface traction of the upper mat constructions of a roadway or platform being with the wheels of vehicles traveling thereover may be increased.
Another very important object of this invention is to provide a mat construction which may be produced at low cost.
Still another object of this invention is to provide a mat construction of simple design which does not require the use of jigs during a mass production thereof.
A further object of this invention is to provide a mat construction which may be of one piece, molded construction.
A still further object of this invention is to provide a mat construction which will require minimum cleaning after each usage upon soft ground.
Yet another object of this invention is to provide a mat construction which may be molded primarily of wood products and resin.
Another object of this invention is to provide a platform mat construction of substantially eight feet in width and which may be made double wide to provide for a single lane roadway with the usual less than eight foot spacing between the wheels of vehicles serving to minimize downward depression of the outer margins of the roadway beneath soft ground over which the roadway is formed.
A final object of this invention to be specifically enumerated herein is to provide a mat construction which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long-lasting and relatively trouble free in operation.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is fragmentary perspective view of a double wide roadway constructed through the utilization of a plurality of right side up and inverted mat constructions of the instant invention and wherein the rectangular planar surface defining member of each mat construction is formed by a single unbroken panel member;
FIG. 2 is a perspective view of a modified form of mat construction wherein the rectangular planar surface defining member is constructed of four plank-type members and wherein each transverse log or member at the opposite ends of rectangular surface defining member is formed of a pair of closely spaces transverse plank members;
FIG. 3 is an enlarged end elevational view of the mat construction illustrated in FIG. 2;
FIG. 4 is an end elevational view of a one piece mat construction wherein the rectangular surface defining member and the transverse logs are integrally formed by a molding process;
FIG. 5 is a reduced bottom plan view of the mat construction illustrated in FIG. 4;
FIG. 6 is an enlarged fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 6--6 of FIG. 1; and
FIG. 7 is a reduced side elevational view of the one piece mat construction illustrated in FIGS. 4 and 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more specifically to the drawings the numeral 10 generally designates a roadway which has been constructed over soft ground utilizing a plurality of mat constructions of the instant invention.
Each mat construction is referred to in general by the reference numeral 12 or 12' and includes a rectangular surface defining member 14 or 14' and a pair of opposite end elongated transverse logs or members 16 or 16'.
Each rectangular surface defining member 14 defines a first rectangular surface 18 and a second rectangular surface 20 facing opposite and paralleling the first surface 18. In addition, each transverse log or member 16 is secured to the opposite ends of the rectangular surface defining member 14 in any convenient manner.
The mat constructions 12' are identical to the mat constructions 12, except that the mat constructions 12' are one-half the width of the mat constructions 12.
The mat constructions 12 and 12' utilize one piece rectangular surface defining members 14 and 14' one piece transverse logs or members 16 and 16'.
When the mat constructions 12 and 12' have their first rectangular surfaces 18 and 18' disposed uppermost, the transverse logs or members 16 and 16' are secured to the undersides of the rectangular surface defining members 14 and 14'. However, when constructing the roadway 10, some mat structures 12 and also the mat structures 12' are disposed with their first rectangular surfaces 18 disposed uppermost and other mat structures 12 are disposed with their first rectangular surfaces 18 disposed lowermost.
The width of the transverse logs or members 16 and 16' is slightly less than one-quarter the length of the rectangular surface defining member 14 and 14' and the spacing between the transverse logs or members 16 and 16' of each mat structure 12 and 12' is slightly greater than one-half the length of the corresponding rectangular surface defining member 14 and 14'. In this manner, when constructing the roadway 10, a double row of mat structures 12 are disposed in end-to-end aligned and abutted relation with their second rectangular surfaces 20 and their transverse logs or members 16 disposed uppermost, see FIG. 6. Thereafter, a first row of mat structures 12 with their first rectangular surfaces 18 disposed uppermost and their transverse logs or members 18 disposed lowermost are centered over the first laid two rows of mat structures 12 in end-to-end aligned and abutting relation with the adjacent transverse logs or members of end abutted upper mat sections 12 received between the transverse logs or members 16 of the lower mats 12 and the transverse logs or members 16 of abutted ends of lower mats 12 received in the spacing between the transverse logs or mats 16 of the upper mat structures 12. Then, two rows of one-half width mat constructions 12' are disposed over the exposed remote side half marginal portions of the first laid two rows of mat constructions 12 with the half width mat constructions 12' aligned transversely of the roadway 10 with the corresponding upper mat structures. In this manner, the upper and lower mat structures 12 and 12' are tightly interlocked together against relative longitudinal shifting and the friction between the upper and lower mat structures 12 and 12' strongly resists relative lateral shifting between upper and lower mat sections 12 and 12'. Further, when a vehicle with slightly less than eight foot spacing between opposite side wheels is driven down the center of the roadway 10 on the center row of upper mat structures 12, the weight of the vehicle is supported more from the adjacent margins of the underlying bottom mat structures 12 and, thus, there is little tendency for soft mud at the longitudinal margins of the roadway 10 to bulge up and overflow the roadway longitudinal margins.
The mat sections 12 and 12' may be constructed entirely of wood with the transverse logs or members 16 and 16' comprising large transverse planks and with the rectangular surface defining members comprising heavy plywood panel sections, both the rectangular surface defining members 14 and 14' and the transverse log or members 16 and 16' being treated against rot.
With attention now invited more specifically to FIG. 2 of the drawings, there may be seen a modified form of mat structure 112 which utilizes four individual plank sections 113 as the rectangular surface defining member thereof and a pair of plank members 116 defining each of the transverse logs or members thereof. The plank members 113 are slightly spaced apart to allow heavily laden rubber tire areas aligned with the spacing between adjacent plank members 113 to be depressed downwardly between adjacent planks 113 in order to increase traction between the tires of wheeled vehicles and the first rectangular surface 118 of the mat structure 112. Here again, the plank members 113 and 116 may be constructed of wood or even molded of wood products mixed with resin. Of course, the mat structure 112 also may be constructed as a one-half mat structure and used in the same manner as the mat structure 12'.
Referring now more specifically to FIG. 4, the reference numeral 212 refers to a third form of mat structure which is of one piece construction and constructed of a mixture of wood chips and resin, or the like. The first rectangular surface 218 of the mat structure 212 includes four integral longitudinally extending, transversely spaced and generally inverted V-shaped ridges 219 for increasing traction between a wheeled vehicle and the first rectangular surface 218. The transverse logs or members 216 or formed integrally with the rectangular surface defining member 214 of the mat structure 212. The ridges 219, in addition to affording increased traction between the first rectangular surface 218 and wheeled vehicles moving thereover, also provide longitudinal stiffening for the mat structure 212. Also, as before, the mat structure 212 may be constructed as a one-half width mat structure.
It has been found that utilizing only two transverse logs or members at the opposite ends of each mat section 12 or 12' results in simplified construction of the mat sections 12 and 12', as opposed to mat sections previously known which incorporate more than two transverse log members or planks and which are interdigitated with relatively inverted mat sections of the same type. Previous mat sections utilizing more than two log members must be constructed through the utilization of jigs to insure proper spacing between the transverse log members and they are more difficult to clean after usage on soft ground to insure that the interdigitation of the log members of relatively inverted mat sections subsequently may be accomplished.
With applicant's invention it is only necessary to provide the rectangular surface defining members 14 and 14' and transverse logs or members 16 and 16' of the correct dimensions. Then, the transverse logs or members 16 and 16' may be readily secured to the opposite ends of the rectangular surface defining members 14 and 14', inasmuch as the transverse logs or members are substantially aligned with the end edges of the rectangular surface defining members 14 and 14' and the opposite side longitudinal margins of the rectangular surface defining members 14 and 14'. This type of construction enables the mat structures 12 and 12' to be assembled by persons having minimum education and instruction while still providing a product which is superior in its ability to be quickly erected in order form a roadway such as the roadway 10 and also its ability to be readily cleaned for subsequent usage.
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 roadway/platform mat construction is provided for disposition over soft ground. The mat construction includes a rectangular, panel-like mat structure including opposite transverse end margins and opposite side longitudinal margins. The mat construction defines a first rectangular surface and a second rectangular surface facing opposite and paralleling the first surface and including elongated transverse log structures carried by the opposite ends of the mat structure and projecting outwardly of the second surface thereof. The transverse logs are of a width measured longitudinally of the mat construction equal to substantially one-quarter the length of the mat construction and the spacing between opposite end logs of each mat construction measured longitudinally thereof is equal to substantially one-half the length of the mat construction. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a sewing machine and, more particularly, to a sewing machine for sewing stitch patterns.
Heretofore, sewing machines of this type have been provided with needle swing cams and work piece feeding cams corresponding to stitch patterns. The operator has selected specified cams for respective stitch patterns to be sewn. Accordingly, complicated stitch patterns have needed cams having a complicated shape which needs a complicated production process with a lower efficiency. The prior art sewing machines have been disadvantageous also in that the operator has to select specified cams for different stitch patterns.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a stitch pattern sewing machine which enables the operator to set stitch pattern data with ease and eliminates the need of producing specified cams for different stitch patterns, thus enabling an easy operation.
The present invention is characterized by a stitch pattern sewing machine comprising a memory circuit for storing as stitch pattern data an initial value indicating needle swing position upon start of stitch, a basic stitch number indicating the number of stitches for the formation of one stitch pattern and quantity of needle swing required for the formation of one stitch pattern, a counter in which the high-order digit portion and the low-order digit portion have the same number of digit, an instruction circuit for instructing stitch pattern to be sewn, a first means for reading from said memory circuit said stitch pattern data corresponding to the instruction from said instruction circuit, a second means for setting said basic stitch number at the low-order digit portion of said counter in accordance with data from said first means, a third means for adding logic value "1" to each digit of the value of said low-order digit portion and cycling the operation when the contents of said low-order digit portion become zero, and a fourth means for setting at least two different needle swing positions in accordance with the results of the operation of said third means.
In accordance with the present invention, a memory circuit for storing as data for each stitch pattern an initial value, basic stitch number and quantity of needle swing and an arithmetic and logic circuit having a high-order digit portion and low-order digit portion both having the same number of digits are provided. With such an arrangement, the basic stitch number is set at the low-order digit portion, and logic value "1" is added to each digit. When the result of the addition is a value other than zero, the needle swing position is set at the initial value. When the result of the addition is zero, the needle swing position is set at the position displaced from the last needle position by the quantity of needle swing stored. In this manner, predetermined stitch patterns are automatically sewn. Accordingly, data for each stitch pattern can be easily set. Furthermore, the present invention has excellent effects that unlike the prior art sewing machine it eliminates the need of producing specified cams for different stitch patterns and enables an easy operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective external view of an essential part of an embodiment of the present invention;
FIG. 2 is a block diagram of an essential part of the embodiment of the present invention;
FIG. 3 is a diagram of the waveform of the output of a needle position detection circuit;
FIGS. 4(a), 4(b) and 5 are flow charts of the embodiment of the present invention;
FIG. 6 is a diagram illustrating a predetermined stitch pattern of the embodiment of the present invention; and
FIG. 7 is a diagram illustrating an arithmetic and logic circuit of the embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the present invention will be described hereinafter by referring to the drawings. FIG. 1 is a perspective external view of the embodiment of the present invention. An arm portion 1 of the sewing machine is provided at its front face with a display panel 2 having a display of stitch patterns 2a to 2k. Shown at 3 is a pattern selection switch which enables a manual operation of selecting one of stitch patterns indicated by the designs 2a to 2k. Connected to a needle 4 which is provided in such an arrangement as to swing in directions perpendicular to the direction of work piece feeding is a stepping motor STM for determining the swing position of the needle 4 (see FIG. 2).
FIG. 2 shows a block diagram of an essential part of an embodiment of the present invention. Connected to CPU 6 are ROM 7 which stores program for the present sewing machine, RAM 8 which stores stitch pattern data, and an arithmetic and logic circuit 11 consisting of a counter 9 in which the high-order digit portion and the low-order digit portion have the same number of digits (e.g. 4 digits) and a substitution circuit 10 for substituting the value of the high-order digit portion with that of the low-order digit portion and vice versa. Also connected to CPU 6 via I/O port 13 are a needle position detection circuit 14 for detecting the position of the needle 4 synchronous with the upper axis angle, the stitch pattern selection switch 3 and a stepping motor STM (hereinafter referred to as "motor STM") for determining the swing position of the needle 4.
FIG. 3 is a view of the waveform of the output signal from the needle position detection circuit 14. The waveform (a) shows a so-called needle locus. The waveform (b) shows an output signal synchronous with the waveform (a). The synchronous signal (b) is outputted at L level signal while the needle 4 is in the needle disengagement state (needle swing period) and as H level signal when the needle 4 is in the needle insertion state (work piece feeding period).
FIGS. 4(a) and 4(b) are flow charts of the embodiment of the present invention. FIG. 5 shows a flow chart of a pattern generation routine (block 17) shown in FIG. 4(b).
The characteristic operation of the embodiment of the present invention having the above arrangement will be described hereinafter. Let us now explain the case where the stitch pattern shown in FIG. 6 is selected by the operation of the pattern selection switch 3. The stitch pattern shown in FIG. 6 has a basic pattern formed of the points A to E. That is, the basic needle number LC of the pattern is 5. The figure in the parenthesis in FIG. 6 indicates the needle swing position. That is, the initial value PX of the needle swing position of the stitch start point A of the pattern is 2. The quantity of needle swing AC from the point D to the point E is 2.
The basic needle number LC, the initial value PX and the quantity of needle swing AC have previously been stored in RAM 8 as stitch pattern data for each stitch pattern.
Once the pattern selection is conducted, the program proceeds to the pattern generation mode where the above stitch pattern data LC, PX and AC are read from RAM 8 (see blocks 18, 19, and 20 in FIG. 4(a)). At this time, a basic needle number LC=5 10 =0101 2 is set into the low-order digit portion LC 1 of the counter 9. CPU 6 then detects the output signal b (hereinafter referred to as "synchronous signal b") from the needle position detection circuit 14. When the synchronous signal b thus detected is at H level, the upper axis is caused to make a half turn so that the needle 4 stops at the needle disengagement section, i.e. the position shown by α in FIG. 3 (see blocks 21 and 22 in FIG. 4(a)). On the other hand, when the synchronous signal b is at L level, the needle 4 is at the needle disengagement section and is then caused to remain at the position (see block 21 in FIG. 4(a)).
Then the pattern generation routine shown in FIG. 5 is conducted (see block 17 in FIG. 4(b)). That is, logic value "1" is added to each digit of the basic needle number LC=0101 2 which has been set into the low-order portion LC 1 in the arithmetic and logic circuit 11 (see block 25 in FIG. 5). FIG. 7 shows the process of this addition. As a result of this operation, the low-order digit portion LC 1 obtains 0100 2 . However, since LC 1 is not zero, the initial value PX=2 is outputted as the needle swing position of the point A (see blocks 26, 27 and 28 in FIG. 5).
This needle swing position (2) is held in CPU 6 as the needle swing data of the point A (see block 30 in FIG. 4(b)). When the drive switch of the sewing machine is then turned on, it causes the sewing machine to be driven by a known driving mechanism (see block 30 in FIG. 4(b)). This causes the needle 4 to be driven in synchronism with the rotation of the upper axis. Similarly, the needle position detection circuit 14 outputs the synchronous signal b in synchronism with the locus of the needle. When the sewing machine is started, the synchronous signal b does not come to an up edge and is at L level (see blocks 32 and 33 in FIG. 4(b)). Therefore, CPU 6 determines that the needle is in the needle swing section and then gives the needle swing data (2) of the point A held at the block 30 to the motor STM to set the needle 4 at the needle swing position (2) of the point A (see block 34 in FIG. 4(b)). If there is an instruction such as sewing machine operation stop and hold lift in this state, the instruction is processed by a known mechanism not shown (see block 31 in FIG. 4(b)).
When an up edge U 1 of the synchronous signal b is detected after there is no such instruction or the above instruction is processed, CPU 6 determines that the needle is in the needle insertion section, i.e. work piece feeding section (see block 32 in FIG. 4(b)). While the needle is in this work piece feeding section, CPU 6 causes the arithmetic and logic circuit 11 to add logic value "1" to each digit of the low-order digit portion LC 1 (see block 17 in FIG. 4(b) and block 25 in FIG. 5). The result of the operation is LC 1 =0011 2 (see B in FIG. 7). However, since LC 1 is not zero, PX=2 is outputted as the needle swing position of the point B (see blocks 27 and 28 in FIG. 5 and B in FIG. 3).
This needle swing position (2) is held in CPU 6 as needle swing data of the point B (see block 30 in FIG. 4(b)). While the needle is in this needle insertion section, the point A is stitched. When the work piece feeding section is finished and the synchronous signal b is at L level (see blocks 33 and 34 in FIG. 4 (b)), the needle swing data (2) of the point B held in clock 30 is given to the motor STM so that the needle 4 is set at the needle swing position (2) of the point B (see block 34 in FIG. 4(b) and b in FIG. 3).
The operation described above is repeated thereafter. That is, if up edges U 2 , U 3 and U 4 of the synchronous signal b are detected at the block 32, the arithmetic and logic circuit 11 performs an operation of determining the needle swing position of the points C, D and E shown in FIG. 7 during the subsequent respective forwarding section. Since LC 1 is not zero at the points C and D, PX=2 is outputted as needle swing data (see blocks 25, 26, 27 and 28 in FIG. 5 and C and D in FIG. 3). The motor STM is driven during the next needle swing section in accordance with the needle swing data so that the needle swing position of the points C and D are determined (see blocks 32, 33 and 34 in FIG. 4(b) and c and d in FIG. 3).
If the operation of the arithmetic and logic circuit 11 gives the value of the low-order digit portion LC 1 =0000 2 , CPU 6 identifies this value (see block 26 in FIG. 5). At this time, a basic needle number LC=5=0101 2 is formed in the high-order digit portion LC 2 (see E in FIG. 7).
After identifying LC 1 =0000 2 , CPU 6 sends a shift pulse to the substitution circuit 10 to substitute the high-order digit portion LC 2 =0101 2 for the low-order digit portion LC 1 =0000 2 and vice versa (see block 35 in FIG. 5 and block 36 in FIG. 7). PX+AC=2+2=4 is outputted as needle swing data of the point E (see blocks 37 and 28 in FIG. 5 and E in FIG. 3). The needle swing position of the point E is determined in the same manner as described above in accordance with the needle swing data (4) of the point E (see blocks 32, 33 and 34 in FIG. 4(b) and e in FIG. 3).
The stitching of the points B to E is conducted during the needle insertion section immediately after the needle swing position is determined. The similar operation is repeated hereinafter until the stitching of the predetermined stitch pattern is finished.
In addition, the work piece feeding means, too, is connected to a stepping motor (not shown) so that the amount of work piece feeding can be predetermined. The stepping motor is adapted to be driven in accordance with data stored in a memory or data obtained as a result of a known arithmetic operation or the needle swing quantity calculation operation in response to the detection of the up edge U. | A sewing machine for stitching a stitch pattern having a predetermined shape in accordance with stitch pattern data, comprising a memory circuit for storing an initial value indicating the needle swing position for stitch start, a basic stitch number indicating the stitch number required for the formation of one pattern, and quantity of needle swing every stitch pattern, a counter in which the high-order digit portion and the low-order digit portion have the same number of digits, and a control circuit for setting said basic needle number into the low-order digit portion of said counter, adding logic value "1" to each digit of the low-order digit portion, determining a needle swing position in accordance with the arithmetic data, and conducting automatic stitch of said stitch pattern in accordance with the needle swing position thus determined. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method and apparatus for laser-based surgery and treatment, in particular of the human body. More specifically, it relates to the use of a femtosecond laser in such a method/apparatus.
[0003] 2. Description of the Related Art
[0004] Many techniques and devices are known for performing surgery or treatment on the human body. All of these known techniques and devices are plagued by the fact that they inherently affect an unduly large region of tissue relative to many small structures as found e.g. in the human brain or the human cardio-vascular system. In other words, conventional techniques and devices do not provide the precision required by doctors and surgeons to avoid “collateral damage” to healthy tissue and structures in the immediate vicinity of the area of treatment/surgery.
[0005] It is an object of the present disclosure to provide both a method and apparatus for surgery/treatment that overcomes the aforementioned deficiencies of the prior art. It is likewise an object of the present disclosure to teach previously unforeseen techniques for treating the human body.
BRIEF SUMMARY OF THE INVENTION
[0006] In accordance with a first aspect, the present disclosure provides an apparatus having a femtosecond laser that emits at least one pulse of laser energy having a pulse duration of less than 100 femtoseconds and a fiber optical channel for conducting said emitted pulse of laser energy to a vicinity of a human body to irradiate a localized area of said human body to effect at least one of:
microsurgery, in particular separation of tumor tissue from said human body, in particular from a brain of said human body, neurosurgery, e.g. capping of a nerve, separation of at least one of an epineurium and a perineurium from a nerve, capping of a cardiac nerve associated with an arrhythmia, capping of a renal nerve associated with blood pressure regulation, treatment of cardiovascular disease, e.g. removal of calcification (e.g. from a heart valve), tissue modification of vulnerable plaque, stimulation of vessel regions (e.g. stimulation of a baroreceptor), sectioning of vessels in preparation for anastomosis or bypass, treatment of the skin, tissue removal for biopsy, treatment of birthmarks or moles, cutting of a mucous membrane, e.g. in paranasal sinuses or a nasal cavity, disintegration or vaporization of a gallstone or a kidney stone, and orthopedic surgery.
[0016] In accordance with a second aspect, the present disclosure provides a corresponding method for effecting any of the aforementioned treatments.
[0017] In accordance with a third aspect, the present disclosure teaches use of a femtosecond laser for manufacturing an apparatus for effecting any of the aforementioned treatments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The novel features of the invention, as well as the invention itself, both as to its structure and its operation will be best understood from the accompanying figures, taken in conjunction with the accompanying description. The Figures show:
[0019] FIG. 1 an apparatus in accordance with the present disclosure
DETAILED DESCRIPTION OF THE INVENTION
[0020] FIG. 1 shows an apparatus 100 having an optional housing 10 . The apparatus 100 comprises a femtosecond laser 20 configured and adapted to output at least one pulse of laser energy. The pulse of laser energy has a duration on the order of femtoseconds, e.g. a duration of less than 100 fs, 50 fs, 10 fs, 5 fs or even 1 fs. The pulse of laser energy is followed by a period in which femtosecond laser 20 does not emit laser energy. This period is at least twice as long as the duration of the preceding pulse of laser energy, yet is typically on the order of several microseconds or larger.
[0021] In accordance with the embodiment shown in FIG. 1 , the pulse of laser energy emitted by femtosecond laser 20 is coupled into an optical channel 51 of a fiber-optic cable 50 . As known in the art of fiber-optic cables, optical channel 51 conducts the laser energy from one end of optical channel 51 to the other end of optical channel 51 with negligible loss. Fiber-optic cable 50 has a length suitable for transmitting the pulse of laser energy from femtosecond laser 20 to the vicinity of or deeply into the cardiovascular system of a patient requiring treatment, e.g. a length of 2 to 6 meters. To allow transmission of the pulse of laser energy deeply into the cardiovascular system, fiber-optic cable 50 can be configured with an extremely small outer diameter, e.g. on the order of 100 to 500 μm. Similarly, fiber-optic cable 50 can be configured to be flexible along its entire length or along a portion of its length, e.g. along at least a portion that is intended to be inserted into the cardiovascular system. In the present context, “flexible” is to be understood as having a small bending radius, e.g. a bending radius on the order of 3-20 mm. The bending radius indicates how sharply the fiber-optic cable 50 can be bent without damaging the fiber-optic cable 50 . Preferably, the bending solely incurs elastic deformation of the fiber-optic cable 50 , i.e. incurs no plastic or other irreversible deformation of the fiber-optic cable 50 .
[0022] To enhance steerability of fiber-optic cable 50 to the area requiring treatment (e.g. through various passages of the patient's cardiovascular system) and to enhance the accuracy with which the laser energy transmitted through optical channel 51 from femtosecond laser 20 can be aimed at a particular region of the patient's body, fiber-optic cable 50 can be provided with a stiff, i.e. substantially inflexible, distal end portion 52 . Choosing an appropriate length for stiff distal end portion 53 involves balancing the desire for flexibility and the desire for steerability/aiming accuracy. For an embodiment of a fiber-optic cable 50 for insertion into the cardiovascular system, a length in the range of 3 to 10 mm for stiff distal end portion 53 has been determined to be appropriate. Similarly, the flexibility of the fiber-optic cable 50 can vary anywhere along the length of the fiber-optic cable 50 , e.g. can vary continuously.
[0023] Aiming of the laser energy transmitted through optical channel 51 from femtosecond laser 20 at a particular region of the patient's body can likewise be accomplished by providing a movable, e.g. a steerable lens at the distal end of optical channel 51 . A steerable lens is of utility e.g. for treating plaque or stenoses along the wall of a vessel that thus surround the tip of the fiber-optic cable 50 . It such cases, it is desirable to direct the laser energy generally in a radially outward direction relative to the axis of the fiber-optic cable 50 rather than in an axial direction.
[0024] For the sake of obtaining feedback with regard to the laser treatment, fiber-optic cable 50 can comprise a feedback optical channel 52 that is configured to capture laser light that has been emitted from the distal end of optical channel 51 and has then been reflected back to the distal end of feedback optical channel 52 by the tissues/structures under treatment or by surrounding tissues/structures. The laser light captured at the distal end of optical channel 52 is then transmitted through fiber-optic cable 50 to an optical processing apparatus 30 where it is subjected to processing, e.g. spectrometric analysis. Such processing/analysis of the light obtained from the area of treatment or its vicinity via feedback optical channel 52 can yield information regarding the type of tissue/structure being irradiated by the laser energy transmitted through optical channel 51 , which can be indicative of the state of progress of the treatment. For example, light reflected from a gallstone will exhibit a different spectral characteristic than light reflected from surrounding tissue. Accordingly, a sudden or sharp decrease in the amount of light received via feedback optical channel 52 having a spectral characteristic indicative of reflection off a gallstone can be indicative of incorrect aiming of the irradiated laser energy or of disintegration of gallstone material previously located in the beam path of the laser energy irradiated from the distal end of optical channel 51 . In either case, a (similarly marked) decrease in the amount of laser energy irradiated per unit of time could be appropriate to prevent unintentional damage to healthy tissue in the beam path.
[0025] As shown in FIG. 1 , apparatus 100 may comprise a control apparatus 40 that is communicatively coupled to optical processing apparatus 30 and femtosecond laser 20 . Control apparatus 40 can be configured to automatically control an output of femtosecond laser 20 based on an input obtained from optical processing apparatus 30 that is indicative of a result obtained by processing the light captured by feedback optical channel 52 as described above. Control apparatus 40 can control the output of femtosecond laser 20 e.g. as regards the pulse duration of laser energy pulses emitted from femtosecond laser 20 , the power of each laser energy pulse emitted from femtosecond laser 20 , the number of pulses per unit of time, the total number of pulses, etc.
[0026] Naturally, apparatus 100 can be configured and adapted to display data indicative of a result obtained by processing the light captured by feedback optical channel 52 as described above to a user. Such a display of data to a user can be in addition to or in lieu of the aforementioned communication of data from optical processing apparatus 30 to control apparatus 40 . Similarly, apparatus 100 can be configured and adapted to receive input from a user regarding control of the femtosecond laser, e.g. as regards the pulse duration of laser energy pulses emitted from femtosecond laser 20 , the power of each laser energy pulse emitted from femtosecond laser 20 , the number of pulses per unit of time, the total number of pulses, etc. Such user control of the femtosecond laser 20 can be in addition to or in lieu of the aforementioned control of the femtosecond laser 20 by control apparatus 40 .
[0027] Femtosecond laser 20 can be controlled so as to emit at least one pulse of laser energy having a power in the range of 0.5 to 5 μJ per pulse. Due to the limited amount of energy emitted per pulse, a volume of less than 1 cubic millimeter of tissue (or other bodily structure) will be affected per pulse. Indeed, femtosecond laser 20 can be controlled such that the volume of affected tissue, depending on the type of tissue/structure being treated, lies in the range of 0.001 cubic millimeters to 0.05 cubic millimeters per pulse. The volume of affected tissue per pulse can even be as low as 1 cubic μm. Accordingly, the volume of affected tissue per pulse can likewise lie in the range of 1 cubic μm to 5 cubic μm, in the range of 5 cubic μm to 10 cubic μm or in the range of 10 cubic μm to 100 μm. As a result, apparatus 100 opens the door to a new dimension of microsurgery including previously unforeseen types of surgery requiring extreme precision.
[0028] In the following, specific aspects of the general disclosure supra will be discussed.
[0029] As stated above, conventional laser systems for medical applications are disadvantageous in that they generate undesired heat in tissue and structures in the vicinity of the region under treatment. Accordingly, conventional laser systems are unsuitable for microsurgery.
[0030] The apparatuses and techniques disclosed herein allow the destruction of tissue with high precision and in a spatially confined region. This allows cutting in a region without damage to adjacent tissue. By adjusting the penetration depth of the laser energy, e.g. by adjusting the focus of the irradiating laser beam, deep, yet exacting cuts can be made.
[0031] The dimensions as well as the mechanical characteristics (such as flexibility) of the cable that transmits the laser pulses are decisive in achieving high precision treatment of regions of the body that are difficult to reach.
[0032] The present disclosure teaches a transmission of laser pulses, in particular having a duration of the order of femtoseconds, through a very thin cable. The cable exhibits an outer diameter that is smaller than 500 micrometers, e.g. less than 300 μm, 250 μm, 200 μm, 150 μm or 100 μm. The cable can be a cable with a hollow core, a mode field diameter fiber or a photonic-crystal fiber. The thin cable can have the length of a catheter, e.g. a length of up to 2 meters, for example for endovascular treatment. In some cases, e.g. for some types of microsurgery, the cable need only be about 0.1 meters in length. The employment of a cable with such small dimensions is only possible in conjunction with a laser that emits pulses having a duration on the order of femtoseconds by limiting the power per pulse to a very small value, e.g. a power of less than 5, 2, 1 or 0.5 μJ per pulse.
[0033] The disclosed cable can be embodied such that at least a portion of the cable that transmits the laser pulse is very flexible. This allows access to regions reachable through tortuous paths. It can also be embodied such that only the (distal) tip of the cable is flexible. This allows regions encountered before the area of treatment to be circumvented as necessary, for example. Similarly, the flexible region can be proximal to the end section and the distal section can exhibit high strength or be very stiff. This allows bodily tissue to circumvented with the entire cable, while simultaneously ensuring high stability at the tip. High stability at the tip ensures that the laser can be accurately aimed during treatment. The flexible catheter region can also be steerable. The laser can be navigated by endoscopic methods.
[0034] The laser cable, i.e. the cable that conducts the laser light to an area of treatment, can comprise a movable, steerable lens. Precise ablation without damage to neighboring regions can be achieved by moving the lens while maintaining the cable in a fixed position.
[0035] Feedback, e.g. spectrometric feedback, can be provided for recognition of the characteristics of the affected tissue, and the system can comprise a control apparatus e.g. for stopping the emission of laser pulses depending on the feedback or information derived therefrom. This makes it possible to treat tissue having known characteristics while neighboring tissue of a different type remains unaffected by the laser. For example, hard tissue/structures such as bone cells can be removed without the danger of damaging neighboring soft tissue such as vessels and nerves.
[0036] The cable/catheter can be provided with at least one flexible region. The flexible region can have a radius of curvature in the range of 3 to 20 mm, e.g. a radius of curvature of less than 20, 15, 10, 8, 5 or 3 mm.
[0037] By using a femtosecond laser, i.e. a laser that emits pulses of laser light having a duration on the order of femtoseconds, it is possible to make cuts without adversely affecting neighboring tissue since the generation of heat is spatially localized. Accordingly, it is possible to remove tissue with high precision in both a lateral and an axial (depth) direction. This precision in both a lateral and axial direction allows deep, yet very precise incisions to be carried out.
[0038] A summary of diseases and conditions that can be treated by such an apparatus/by such techniques based on a femtosecond laser in conjunction with an extremely thin (and optionally flexible) cable follows.
[0039] Neurosurgery/minimal invasive surgery:
[0040] The apparatuses and techniques described above can be used for tumor removal, in particular in the region of the brain. Many tumors cannot be removed because injury to the proximal tissue would be unacceptable. By using a thin and flexible cable, areas can be reached for treatment that are otherwise not easily or feasibly accessible. By using a femtosecond laser, it is possible to excise the tumor or parts thereof with extreme precision. Tumors commonly grow into healthy tissue, whence it is often necessary to excise some of the healthy tissue proximal to the tumor to ensure complete removal of the tumorous tissue. By using a femtosecond laser, it is possible to reduce the amount of healthy tissue removed to a minimum.
[0041] Naturally, the minimally invasive laser treatment apparatuses and techniques described above can be used for tumor removal from other regions of the body and other types of bodily tissue. Moreover, these apparatuses and techniques can provide novel forms of laser treatment. For example, instead of cutting or excising a tumor, the femtosecond laser can be used to biologically alter the cancerous cells without substantial destruction or removal of tissue. Specifically, the amount of laser energy irradiated onto the area of treatment can be dosed, e.g. as described above, such that the outer structure of the cells remains intact, yet their inner structure is biologically modified.
[0042] The apparatuses and techniques described above can be used for treatment of the nervous system, including treatment of nerves and separation of nerves from one another. The separation of nerves is of importance, for example, in the field of pain therapy, e.g. in the treatment of worn-out joints and neurological diseases. Since nerves are often grouped in bundles, conventional surgical techniques almost always result in a cutting of several nerves. It is thus desirable to carefully and exactingly separate the individual nerves that run parallel to one another. This can be achieved by the apparatuses and techniques taught herein. Moreover, the laser is capable of precisely capping one or more individual nerves. The small dimensions of the fiber-optic cable play a decisive role in this respect since sections of other important nerves may run very close to the nerve or nerves to be capped.
[0043] The teachings of the present disclosure are similarly applicable to an ablation of the outer membranes of a nerve, e.g. the epineurium or the perineurium, for the sake of treating the nerves encased therein.
[0044] Cardiovascular and endovascular treatment:
[0045] Clogged, e.g. due to calcification, heart valves in be treated via the precision laser techniques and apparatuses taught herein. By applying the focus of the laser to a very small region (in this case mainly axially, i.e. primarily deeply into the tissue with minimal lateral expanse), the clogging/calcified region can be removed with negligible damage to neighboring healthy tissue. The flexibility and the very small diameter of the cable are advantageous in this respect and since that allows the system to be introduced into the area of treatment endovascularly, e.g. intravenously, from a peripheral vessels, for example from a femoral vein or a fermoral artery (e.g. for the treatment of heart valves in the left ventricle). Employment of such a technique avoids the necessity of surgical treatment of the heart valve. Accordingly, the aorta need not be opened, which avoids the need for connecting the patient to a heart-lung machine and the substantial risks associated therewith.
[0046] Clogged blood vessels that limit blood flow, i.e. blood vessels with stenosis, can be treated intravenously by means of a thin microcatheter as described hereinabove. Similarly, blood vessels soft plaque (also known as vulnerable plaque) can be safely treated by transmitting the laser light inside a thin, flexible catheter to the area of treatment. In contrast, mechanical surgery of soft plaque is undesirably dangerous since pieces of plaque can be uncontrollably detached, i.e. can be released into the bloodstream, and can thus lead to obstruction in a remote vessel of the cardiovascular system with a possibly crippling or lethal effect. As discussed above, employment of a femtosecond laser allows ablation of the areas of plaque without damaging the neighboring tissue. Another particular advantage of this technique is that soft plaque and calcified tissue are effectively so finely vaporized by the laser that the vaporized tissue can be absorbed from the bloodstream without problems. The teachings of the present disclosure thus provide considerable advantages over mechanical surgery of soft plaque or intervention through mechanical systems such as stents.
[0047] As discussed supra, the techniques and apparatuses of the present disclosure can be used for capping, i.e. severing, nerves, e.g. in the heart for treatment of arrhythmia, without damaging the neighboring tissue. The laser pulse can be introduced into the body endovascularly or an incision can be made in the inner wall of a cardiac chamber. The incision can also be made from outside the body, e.g. using endoscopic techniques. As compared to high-frequency ablation or cryoablation, the teachings of the present disclosure are advantageous inter alia on account of their spatial accuracy and the small dimensions of the instruments involved.
[0048] A further, similar application is the capping of nerves in the renal arteries, which allows the blood pressure to be influenced, e.g. for the sake of lowering a patient's blood pressure.
[0049] The teachings of the present disclosure can also be used for vaporizing/disintegrating thrombi with high precision.
[0050] The teachings of the present disclosure can be used for stimulating specific regions in the cardiovascular system. For example, baroreceptors in the cardiovascular system that are responsible for triggering contraction of vascular muscles and consequently for regulating the flow of blood and for regulating blood pressure can be stimulated by means of the laser.
[0051] The teachings of the present disclosure can also be used for surgically cutting vessels in preparation for bypasses or anastomoses.
[0052] Treatment of the skin:
[0053] Skin diseases and irregularities (e.g. as a result of acne, calluses or wrinkles) can be treated by means of a femtosecond laser as taught hereinabove.
[0054] The teachings of the present disclosure can also be used for carrying out a biopsy, e.g. with respect to a birthmark, mole or other skin irregularity suspected of being carcinogenic or cancerous, without damaging the neighboring tissue and without stimulating what may be malignant tissue. This approach also significantly reduces bleeding.
[0055] The teachings of the present disclosure are also of particular utility for making precise incisions in mucous membranes, e.g. as found in the nose and the paranasal sinuses.
[0056] Orthopedic surgery:
[0057] In the case of arthrosis and many forms of arthritis, there is a wearing of the joints, for example in the knees, hips, wrists or thumb region. The cartilage that covers the bones in the region of the joint protects each bone from wear during the relative motion with respect to the other bone(s) in the joint. When the cartilage is worn, some portions of the bones in the joint contact one another, which can lead to unphysiological growth in the region of contact. Bone protuberances and other irregularities can result that lead to considerable restrictions of mobility and a considerable pain. Using a femtosecond laser as taught herein, it is possible to ablate such protuberances and irregularities endoscopically in a minimally invasive fashion. In the case of implantation of an artificial joint, it is typically desirable to smooth or otherwise fashion the joint region of the respective bones in a precise manner using ablation. This allows the artificial joint to be correctly positioned and properly fastened. The teachings of the present disclosure can be used for this purpose.
[0058] The teachings of the present disclosure are likewise of utility in the treatment of so-called “impingement syndrome.” The term “impingement syndrome” is used to designate impaired joint mobility, specifically arising from degeneration or pinching of capsule or tendinous material. This can arise from a thickening of a tendon (e.g. in the shoulder region) or from anomalies in bone structures (for example as a result of an accident, e.g. to the hip or shoulder) that impede normal joint mobility. The pulses of laser energy can be used to excise or pulverize protuberences or overgrowth.
[0059] The teachings of the present disclosure can be similarly used for treatment of the spinal column, e.g. for ablation of tissue components (e.g. from the nucleus and/or annulus) of the discs or for ablation of bone constituents of the spinal column.
[0060] Treatment of the kidneys or gallbladder:
[0061] The teachings of the present disclosure can also be employed for disintegration of kidney stones, gallstones and the like. Feedback of the laser can be carried out in such a fashion that only the hard substances are disintegrated while the adjacent soft organ tissue is kept intact.
[0062] Biopsies:
[0063] The use of a femtosecond laser as taught herein provides significant advantages as regards obtaining small tissue samples from various organs and various regions of the body, in particular those that are difficult to access. In the case of tumor cells, for example, tissue is not spread. The sample taking is also less traumatic on account of the smaller and more precise cut. Indeed, it becomes possible to obtain tissue samples from regions of the human body that are not feasibly accessible by previously known techniques.
[0064] While various embodiments of the present invention have been disclosed and described in detail herein, it will be apparent to those skilled in the art that various changes may be made to the configuration, operation and form of the invention without departing from the spirit and scope thereof. | The present invention relates to a method and apparatus for laser-based surgery and treatment, in particular of the human body. Inter alia, the present disclosure teaches an apparatus having a femtosecond laser that emits at least one pulse of laser energy having a pulse duration of less than 100 femtoseconds and a fiber optical channel for conducting said emitted pulse of laser energy to a vicinity of a human body to irradiate a localized area of said human body to effect at least one of microsurgery, neurosurgery, treatment of cardiovascular disease, treatment of the skin, tissue removal for biopsy, cutting of a mucous membrane, disintegration or vaporization of a gallstone or a kidney stone, and orthopedic surgery. | 0 |
RELATED APPLICATIONS
[0001] This application is related to (MERL-2218) U.S. patent application Ser. No. 12/630,498 entitled “Wireless Energy Transfer with Negative Index Material,” filed by Koon Hoo Teo et al. on Dec. 3, 2009, (MERL-2221) U.S. patent application Ser. No. 12/630,543 entitled “Wireless Energy Transfer with Negative Index Material,” filed by Koon Hoo Teo et al. on Dec. 3, 2009, (MERL-2222) U.S. patent application Ser. No. 12/630,669 entitled “Wireless Energy Transfer with Negative Material,” filed by Koon Hoo Teo et al. on Dec. 3, 2009, (MERL-2223) U.S. patent application Ser. No. 12/630,710 entitled “Wireless Energy Transfer with Negative Index Material” filed by Koon Hoo Teo et al. on Dec. 3, 2009, all incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to transferring energy, and more particularly, to transferring energy wirelessly.
BACKGROUND OF THE INVENTION
Wireless Energy Transfer
[0003] Inductive coupling is used in a number of wireless energy transfer applications, such as charging a cordless electric toothbrush or hybrid vehicle batteries. In coupled inductors, such as transformers, a source, e.g., primary coil, generates energy as an electromagnetic field, and a sink, e.g., a secondary coil, subtends that field such that the energy passing through the sink is optimized, e.g., is as similar as possible to the energy of the source. To optimize the energy, a distance between the source and the sink should be as small as possible, because over greater distances the induction method is highly ineffective.
Resonant Coupling System
[0004] In resonant coupling, two resonant electromagnetic objects, i.e., the source and the sink, interact with each other under resonance conditions. The resonant coupling transfers energy from the source to the sink over a mid-range distance, e.g., a fraction of the resonant frequency wavelength.
[0005] FIG. 1 shows a conventional resonant coupling system 100 for transferring energy from a resonant source 110 to a resonant sink 120 . The general principle of operation of the system 100 is similar to inductive coupling. A driver 140 inputs the energy into the resonant source to form an oscillating electromagnetic field 115 . The excited electromagnetic field attenuates at a rate with respect to the excitation signal frequency at driver or self resonant frequency of source and sink for a resonant system. However, if the resonant sink absorbs more energy than is lost during each cycle, then most of the energy is transferred to the sink. Operating the resonant source and the resonant sink at the same resonant frequency ensures that the resonant sink has low impedance at that frequency, and that the energy is optimally absorbed. Example of the resonant coupling system is disclosed in U.S. Patent Applications 2008/0278264 and 2007/0222542, incorporated herein by reference.
[0006] The energy is transferred, over a distance D, between resonant objects, e.g., the resonant source having a size L 1 and the resonant sink having a size L 2 . The driver connects a power provider to the source, and the resonant sink is connected to a power consuming device, e.g., a resistive load 150 . Energy is supplied by the driver to the resonant source, transferred wirelessly and non-radiatively from the resonant source to the resonant sink, and consumed by the load. The wireless non-radiative energy transfer is performed using the field 115 , e.g., the electromagnetic field or an acoustic field of the resonant system. For simplicity of this specification, the field 115 is an electromagnetic field. During the coupling of the resonant objects, evanescent waves 130 are propagated between the resonant source and the resonant sink.
Coupling Enhancement
[0007] According to coupled-mode theory, the strength of the coupling is represented by a coupling coefficient k. The coupling enhancement is denoted by an increase of an absolute value of the coupling coefficient k. Based on the coupling mode theory, the resonant frequency of the resonant coupling system is partitioned into multiple frequencies. For example, in two objects resonance compiling systems, two resonant frequencies can be observed, named even and odd mode frequencies, due to the coupling effect. The coupling coefficient of two objects resonant system formed by two exactly same resonant structures is calculated by partitioning of the even and odd modes according to
[0000] κ=π| f even −f odd | (1)
[0008] It is a challenge to enhance the coupling. For example, to optimize the coupling, resonant objects with a high quality factor are selected.
[0009] Accordingly, it is desired to optimize wireless energy transfer between the source and the sink.
SUMMARY OF THE INVENTION
[0010] Embodiments of the invention are based on a realization that tuning a dominant frequency of a source or a sink of a wireless energy transfer system enables at least four different electromagnetic (EM) energy distribution patterns having maximum intensities in different zones. This realization allows transferring energy in different direction with optimized efficiency.
[0011] One embodiment of the invention provides a system configured to exchange energy wirelessly, comprising a structure configured to exchange the energy wirelessly via a coupling of evanescent waves, wherein the structure is electromagnetic (EM) and non-radiative, and wherein the structure generates an EM near-field in response to receiving the energy; and a controller configured to tune the structure such that the near-field is generated according a particular energy distribution pattern.
[0012] Another embodiment of the invention provides a method for exchanging energy wirelessly via a coupling of near-fields, comprising steps of providing a first structure configured to exchange energy wirelessly with a second structure via the coupling of near-fields of the first structure and the second structure, wherein the first and the second structures are electromagnetic (EM) and non-radiative, and wherein the first and the second structures generate EM near-fields in response to receiving the energy; determining an orientation between the first structure and the second structure; tuning a dominant frequency of the first structure such that the near-field of the first structure is generated according a particular energy distribution pattern optimal for the orientation; and exchanging energy wirelessly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a block diagram of a conventional resonant coupling system;
[0014] FIG. 2A is a schematic of a system suitable to transfer or receive energy wirelessly according to an embodiment of the invention; and
[0015] FIGS. 2B-5 are schematics of different embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Embodiments of the invention are based on a realization that tuning a dominant frequency of a source or a sink of a wireless energy transfer system enables the generation of at least four different electromagnetic (EM) energy distribution patterns with maximum intensities in different zones. This realization allows transferring energy in different direction with optimized efficiency.
[0017] FIG. 2A shows an embodiment of our invention configured to optimized wireless energy transfer form a tunable source 210 to multiple sinks. When the driver 240 supplies the energy 260 to the source 210 , the source generates an EM field 215 . Typically, the near-field 215 is generated according to a particular energy distribution pattern. The pattern, as described below, has different zones, such as optimum zones, wherein near-field intensities are optimal, i.e., maximum, and blind zones, wherein the near-field intensities are minimized.
[0018] In some applications, it is advantageous to transfer the energy to more than one sink, e.g., to the sink 1 221 and to the sink 2 222 . However, if the sink 1 occupies the optimal zone of the energy distribution pattern of the source, the sink 2 can be located in the blind zone of the pattern. Therefore, a controller 270 tunes the dominant frequency of the source 210 to change the energy distribution pattern 215 to another energy distribution pattern 216 , wherein the optimal zone of the pattern 216 replaces the blind zone of the pattern 215 . In one embodiment, the pattern 215 is either even or odd butterfly pattern, and the pattern 216 is either even or odd crossing pattern.
[0019] An orientation between the source and the sink is used to determine a particular optimal pattern for wireless energy transfer between the source and the sink. Accordingly, the embodiments facilitate reusing one source to transfer energy optimally to multiple directions corresponding to locations of different sinks. Similarly, one sink can receive the energy from multiple sources, i.e., from different directions.
[0020] In one embodiment, the tuning of the dominant frequency is achieved by an oscillator, e.g., a voltage or a digital controlled oscillator. A controller 270 monitors a control signal, e.g., voltage or digital signal, of the oscillator to achieve the desired resonant frequency for the system. Examples of such oscillators are oscillators manufactured by Digi-key, and Narda companies. Another example is the Crysteck corporation oscillator (model no: CVCO55CL-0060-0110), which provides frequency tuning range from 60 MHz to 110 MHz with tuning voltage changing from 0.5V to 9.5V.
[0021] FIG. 2B shows a system 200 according an embodiment of the invention. The system is configured to exchange, e.g., transmit or receive, energy wirelessly. The system includes the structure 210 configured to generate an electromagnetic field 220 when the energy is received by the structure and exchange the energy wirelessly via a coupling of evanescent waves.
[0022] In one embodiment, the energy 260 is supplied by the driver 240 . In this embodiment, the structure 210 serves as a source of the wireless energy transfer system. In an alternative embodiment, the energy 260 is supplied wirelessly from the source (not shown). In that embodiment, the structure 210 serves as a sink of the wireless energy transfer system.
[0023] The system 200 optionally includes a negative index material (NIM) 231 - 233 arranged within the near-field 220 . The NIM is a material with negative permittivity and negative permeability properties. Several unusual phenomena are known for this material, e.g., evanescent wave amplification, surface plasmoni-like behavior and negative refraction. Embodiments of the invention appreciated and utilized the unusual ability of NIM to amplify evanescent waves, which optimizes wireless energy transfer.
[0024] In one embodiment, the NIM 233 substantially encloses the EM structure 210 . Enclosing the EM structure with NIM is advantageous for increasing the coupling of evanescent waves between the source and the sink. In variations of this embodiment, the NIM can enclose the source, the sink or both. In one embodiment, there is a gap between the NIM and the EM structure. In another embodiment, multiple layers of the NIM are used.
[0025] The shape and dimensions of the near-field, i.e., the energy distribution pattern, depends on a frequency of the external energy 260 , and on a resonant frequency of the EM structure 210 , determined in part by a shape of the EM structure, e.g., circular, helical, cylindrical shape, and parameters of a material of the EM structure such as conductivity, relative permittivity, and relative permeability.
[0026] Usually, a range 270 of the near-field is in an order of a dominant wavelength of the system. In non resonant systems, the dominant wavelength is determined by a frequency of the external energy 260 , i.e., the wavelength λ 265 . In resonant systems, the dominant wavelength is determined by a resonant frequency of the EM structure. In general, the dominant wavelength is determined by the frequency of the wirelessly exchanged energy.
[0027] The resonance is characterized by a quality factor, i.e., a dimensionless ratio of stored energy to dissipated energy. Because the objective of the system 200 is to transfer or to receive the energy wirelessly, the frequency of the driver or the resonant frequency is selected such as to increase the dimensions of the near-field region. In some embodiments, the frequency of the energy 260 and/or the resonant frequency is in diapason from MHz to GHz. In other embodiments, aforementioned frequencies are in the light domain.
[0028] Evanescent Wave
[0029] An evanescent wave is a near-field standing wave with an intensity that exhibits exponential decay with distance from a boundary at which the wave is formed. The evanescent waves 250 are formed at the boundary between the structure 210 and other “media” with different properties in respect of wave motion, e.g., air. The evanescent waves are formed when the external energy is received by the EM structure and are most intense within one-third of a wavelength of the near field from the surface of the EM structure 210 .
[0030] Whispering Gallery Mode
[0031] Whispering gallery mode (WGM) is the energy distribution pattern in which the evanescent waves are internally reflected or focused by the surface of the EM structure. Due to minimal reflection and radiation losses, the WGM pattern reaches unusually high quality factors, and thus, WGM is useful for wireless energy transfer.
[0032] FIG. 3 shows an example of the EM structure, i.e., a cylinder 310 . Depending on material, geometry and dimensions of the cylinder 310 , as well as the dominant frequency, the EM near-field intensities and energy density are maximized at the surface of the disk according to a WGM pattern 320 .
[0033] The WGM pattern is not necessarily symmetric to the shape of the EM structure. The WGM pattern typically has blind zones 345 , in which the intensity of the EM near-field is minimized, and optimal zones 340 , in which the intensity of the EM near-field is maximized. Some embodiments of the invention place the NIM 230 in the optimal zones 340 to extend a range of the evanescent waves 350 .
[0034] Even and Odd Modes
[0035] FIG. 4 shows a butterfly energy distribution pattern. When two EM structures 411 and 412 are coupled to each other forming a coupled system, the dominant frequency of the coupled system is represented by even and odd frequencies. The near-field distribution at even and odd frequencies is defined as even mode coupled system 410 and an odd mode coupled system 420 . Typical characteristic of the even and the odd modes of the coupled system of two EM structures is that if the EM field is in phase in the even mode then the EM field is out of phase in the odd mode.
[0036] Butterfly Pair
[0037] The even and odd mode coupled systems generate an odd and even mode distribution patterns of the near-field intensities defined as a butterfly pair. The EM near-field intensity distribution of the butterfly pair reaches minimum in two lines 431 and 432 oriented at 0 degree and 90 degree to the center of each EM structure, i.e., blind zones of the butterfly pair. However, it is often desired to change the intensity distribution and eliminate and/or change the positions and/or orientations of the blind zones.
[0038] Crossing Pair
[0039] FIG. 5 shows distribution patterns of the near-field intensities according embodiments of the invention define as a crossing pair 500 . The crossing pair distribution pattern has optimal zones 531 and 532 oriented at 0 degree and 90 degree to the center of each EM structure, i.e., the optimal zones of the crossing pair pattern corresponds to the blind zones of the butterfly pair pattern. Therefore, one important characteristic of the butterfly pair and the crossing pair patterns is that their respective blind zones are not overlapping, and thus eliminates the blind zones when both kinds of patterns are utilized. Butterfly and crossing patterns have system quality factors and coupling coefficient of the same order of magnitude.
EFFECT OF THE INVENTION
[0040] Embodiments of the invention tune the dominant frequency of the source to generate at least four different energy distribution patterns. Those patterns include the butterfly pair pattern and the crossing pair pattern. The orientation between the source and the sink is used to determine a particular pattern optimal for wireless energy transfer between the source and the sink. Accordingly, the embodiments facilitate reusing one source to transfer energy optimally to multiple directions corresponding to locations of different sinks. Similarly, one sink can receive the energy from multiple sources, i.e., from different directions.
[0041] Although the invention has been described by way of examples of preferred embodiments, it is to be understood that various other adaptations and modifications may be made within the spirit and scope of the invention. Therefore, it is the object of the appended claims to cover all such variations and modifications as come within the true spirit and scope of the invention. | Embodiments of the invention disclose a method and a system configured to exchange energy wirelessly, comprising a structure configured to exchange the energy wirelessly via a coupling of evanescent waves, wherein the structure is electromagnetic (EM) and non-radiative, and wherein the structure generates an EM near-field in response to receiving the energy; and a controller configured to tune up the structure such that the near-field is generated according a particular energy distribution pattern. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of, and claims priority of, prior application Ser. No. 08/686,860 filed on Jul. 26, 1996 now abandoned, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The field of this invention is a process for making acrylic resins suitable as polymeric surfactants used in emulsion polymerization, as pigment grinding resins and for preparing dispersions used as overprint varnishes.
BACKGROUND OF THE INVENTION
Poly(α-methyl styrene-co-acrylic acid-co-styrene) and poly(styrene-co-acrylic acid-co-methacvrylic acid), acrylic resins, are used as a polymeric surfactant in emulsion polymerizations, as a pigment grinding resin and for preparing dispersions used to make overprint varnishes. In use, the resins are suspended in water and made into a dispersion, also known as a latex, by neutralizing them with a base such as 28% ammonium hydroxide. The base allows the acrylic resin to form polymeric surfactant micelles which have two chief advantages over solvent based systems. Firstly, they have lower viscosity, which is especially evident in high-solids systems. More importantly, however, is that being substantially solvent free, they are more environmentally friendly than solvent-based systems.
Typically, the acrylic resin has been made by bulk polymerization in a continuous-stirred tank reactor (CSTR). The CSTR is charged with styrene or styrene plus α-methyl styrene, (meth)acrylic acid, a polymerization initiator and a solvent or just with styrene, α-methyl styrene and (meth)acrylic acid. Reaction temperatures range from 180° C. to 300° C. and residence times are from 1 to 60 minutes. Of course, level control is very important. However, pressure is not controlled. The once-through percent conversion is on the order of 75%. The acrylic resin/unreacted monomer reaction product is sent to a devolatilizer for stripping of unreacted monomers for reuse. What emerges from the devolatilizer is the desired acrylic resin, suitable for flaking, pelletizing, pulverization, etc.
Heretofore, it has been believed that the reaction pressure appears to have no significant effect on the yield, and hence, pressure has not been controlled. Also, the use of tubular reactors for the bulk polymerization of styrenics has been taught away from because of problems encountered in thermal runaway reactions at 297° C., which resulted in resins having unacceptably large polydispersion. Past suggestions for avoiding this problem include the use of CSTRs with installed internal cooling coils.
The continuous tube reactor (CTR), also known as the linear flow reactor, has seen wide use in polymerizations because of its simplicity. No level controls are required, and because there is no stirring, there is no need for expensive, rotating seals capable of withstanding the pressure, temperature and solvent effects of the reaction. In the case of acrylics, it has been used in suspension polymerizations; the monomers employed are usually water soluble.
Note that all quantities appearing hereinafter, except in the examples are to be understood as being modified by the term "about." Also, all percentages are weight percentages unless indicated otherwise.
SUMMARY OF THE INVENTION
The invention is a bulk polymerization process for preparing a solid acrylic resin, which comprises the steps of: charging into a continuous tube reactor, a feedstock of at least one vinylic monomer and a polymerization initiator; maintaining a flow rate through the reactor sufficient to provide a residence time of the feedstock in the reactor of from one minute to one hour; maintaining a pressure of 80 psig to 500 psig; maintaining the resulting molten resin mixture with a heat transfer medium within the range from 180° C. to a maximum of 260° C.; and devolatilizing the molten resin mixture exiting the reactor to remove unreacted monomers to provide a solid acrylic resin upon cooling. A preferred embodiment comprises the additional step of recycling the unreacted monomers recovered during the devolatilization step and charging them into the continuous tube reactor as a fraction of the feedstock.
Unexpectedly, the consequences of thermal runaway, mentioned as a concern in the prior art, may be avoided by limiting the reaction pressure and allowing vapor formation.
Another surprise is that the yield is a strong function of the pressure when acrylic resin is made in a CTR. Conversion can be made to vary from 60% to 99% by varying the pressure.
Unforeseen also, was that coatings derived from resin made with recycled monomer showed an improved property, gloss on white, when compared to those derived from virgin monomer, as well as when compared to the closest commercial alternate resin.
An environmental benefit of the invention is that, for many embodiments, no solvent is required to make the resin and coating systems made from it are predominantly water based, rather than solvent based.
DETAILED DESCRIPTION OF THE INVENTION
The monomers are polymerized using a single-pass flow-through tubular reactor. A monomer blend and a polymerization initiator blend are separately introduced and then combined via stainless steel tubing. Prior to combination, the monomer blend may be preheated by pumping through a preheating section of tubing which is dipped into an oil bath set for a preselected temperature. The preheating ensures that the temperature of the monomer blend will be increased to a desired initiation temperature level prior to entering the tubular reactor. The preheating step is not essential to the process. The combined flows then enter a static mixer where the two streams are homogeneously mixed. At this point a small amount of initiation may occur if the monomer blend is preheated. After exiting the static mixer, the combined flows then enter the tubular reactor. The reactor consists of a single tube or a series of tubes of increasing diameter bound in a coil with a single pass. The tubes are plain with no static mixer or other mixing elements therein or in combination therewith after the combined flows enter the tubular reactor. The coil is immersed into a circulating oil bath preset at the desired temperature. Initiation and polymerization occur as the combined flows enter the tubular reactor, conversion is high and the reaction is essentially complete as evidenced by the presence of polymerized resin. Unexpectedly, the single-pass flow-through tubular reactor will efficiently accomplish the desired result under the stated conditions.
The particular reactor used for the following examples is constructed of five 20 foot lengths of 1/2 inch outside diameter (O.D.) tube, three lengths of 20 foot 3/4 inch O.D. tube and two lengths of 1 inch O.D. tube, all 18 gauge 316 stainless steel. They are joined in series and contained in a shell that is 21 feet long and 8 inches in diameter which contains recirculating hot oil as the heat transfer medium.
The design details are not particularly critical, and the reactor size can be scaled up or down within limits. However, the back pressure of the reactor is sensitive to the tube diameter, length and roughness, the number and radii of the connections as well as the changing rheological properties of the reaction mixture as it is converted to polymer as it travels the length of the tubing. These are computationally intractable and the optimal pressure control for each reactor design must be developed experimentally as the conversion rate, as will be seen, is a strong function of the pressure in a CTR. The minimum pressure, which is 80 psig, should be higher than the vapor pressures of the monomers at the heating oil temperature. The upper bound will depend on the hoop strength of the tubing used, the upper bound determined by economics and poor heat transfer, it may be reasonable to expect this to be 500 psig. For the reactor described, the optimal pressure range is from 100 to 300 psig. In this range, the conversion can vary from 60% to 99%.
In terms of mode of operation of the invention, it may be speculated that in a CSTR the pressure is not a variable independent of the temperature because a CSTR will have a headspace filled with vapor in thermodynamic equilibrium with the monomers. While not completely understood, the pressure in a CTR may be a variable that is at least partially independent of the temperature. While the formation of at least some vapor phase has been observed through a transparent tube reactor as transient foaming at the initiation of polymerization, it has been suggested that perhaps the continuous dynamic phase change in the CTR inhibits the establishing of thermodynamic equilibrium within the reactor. Beyond this, it can only qualitatively be stated that lower pressures increase vapor fraction and therefore reduce the residence time, hence the conversion. In order to obtain acceptable conversion and properties, the pressure should be simultaneously optimized with both temperature and residence time.
If the heat transfer fluid temperature is controlled to a maximum of 260° C. (500° F.), then it is possible to use a CTR to make acrylic resin without the danger of thermal run-away. Nor is there need for internal cooling coils and their inherent thermodynamic inefficiency. The lower bound for the temperature is 180° C. At this temperature, conversion is so slow that residence times become uneconomically long and the viscosities are too high to handle. The preferred temperature range for this reactor and monomer/initiator mixture is from 204° C. (400° F.) to 260° C. (500° F.); more preferred is 210° C. (410° F.) to 246° C. (475° F.). It may reasonably be expected that a longer tube will require lower temperature for equal conversion, while larger O.D. or thicker walls might necessitate higher temperatures. Note that while the heat transfer fluid is limited to 260° C., the stream at the reactor exit can be as high as 271° C.
The residence time lower limit is bounded by 1 minute, conversion being low. On the upper end there are diminishing returns on percent conversion as well as economic waste for needless dwell time; this limit is 1 hour. Also, polymer properties suffer at higher residence times. The preferred dwell time for this reactor is optimized simultaneously with the pressure and temperature, as described above, and is 150 to 250 seconds.
While no solvent is required, solvent can, of course, be added. Glycol ethers are the class of solvents most commonly encountered; diethylene glycol monoethylether and diethylene glycol dimethyl ether are examples and they are typically used at levels of up to 25%.
The feedstock should comprise at least one unreacted vinylic monomer. It is further preferred that the feedstock comprises a blend of vinylic monomers containing at least one acrylic monomer and at least one monoalkenyl aromatic monomer. Monoalkenyl aromatic monomers that can be used include vinyl toluene, para-methyl-styrene, tert-butyl-styrene and chlorostyrene, but preferred are styrene and α-methyl-styrene. Acrylic monomers that may be used include acrylic, methacrylic acid, crotonic acid and their esters and derivatives and maleic anhydride. Among them are butyl acrylate, 2-ethylhexylacrylate, 2-ethylhexylmethacrylate, methylmethacrylate, hydroxyethylmethacrylate and the like. Acrylic and methacrylic acid are preferred. The preferred blends comprises styrene, α-methyl styrene and acrylic acid and styrene, acrylic acid and methacrylic acid. Styrene and α-methyl styrene are hydrophobic, while (meth)acrylic acid is hydrophilic, especially when neutralized to a salt. In order to produce a dispersible polymeric surfactant, the hydrophobic portion must have a certain balance with the hydrophilic portion. Pure acrylic acid would result in polyacrylic acid, which forms a true solution in water, rather than a dispersion. Pure polystyrene or poly(styrene-co-α-methyl styrene) will not disperse in water because it has no hydrophilic functionality, nor an acid group whose hydrophilicity can be increased via neutralization. The composition range of styrene plus α-methyl styrene versus (meth)acrylic acid that has produced successful dispersions is 50 to 80 wt. % styrene plus α-methyl styrene and 18 to 40 wt. % (meth)acrylic acid, balance being initiator and any solvent. The ratio of styrene to α-methyl styrene is broader, as both are of the same character, hydrophobic, and may vary from 2.5:1 to 20:1. In terms of mole % of the monomers, the preferred ranges are 25 to 60% styrene, 2 to 35% alpha-methyl styrene and 25 to 50% acrylic acid.
With respect to the styrene, acylic acid and methacrylic acid embodiment, ratios of 1:2:1, 1:1:1 and 1:3:1 mole ratios are possible, giving a range of styrene:(methacrylic acid) of 1:2 to 1:4 moles.
Recycling of the monomers recovered from the reaction mass exiting the reactor as distillate from the devolatilization step is a preferred embodiment. As will be seen in the examples, the properties of the acrylic resins so produced, especially glossiness of the coatings made therefrom, are significantly improved. Typically, 10 wt. % of the feed consists of recycled monomer, however, at least 80 wt. % of the recovered monomers can be recycled. The recycled monomers may require pre-processing such as purification.
The polymerization initiator is of the free radical type with a half-life ranging from 1 to 10 hours at 90 to 100° C. Preferred are initiators with half-lives of 10 hours at 100° C. Initiators of this sort may be azo-type, such as azo-bis isobutyronitrile (AIBN), 1-tert-amylazo-1-cyanocyclohexane and 1-tert-butylazo-1-cyanocyclohexane. They may also be peroxides and hydroperoxides such as tert-butylperoctoate, tert-butylperbenzoate, dicumyl peroxide and tert-butyl hydroperoxide. Preferred are di-tert-butyl peroxide and cumene hydroperoxide. The quantity of initiator typically used ranges from 0.0005:1 to 0.06:1 moles initiator per mole monomer. When di-tert-butyl peroxide is used it is preferred that it is at 0.002 to 0.05 mole ratio, preferably from 0.003 to 0.04 mole ratio. For the styrene, acrylic acid and methacrylic acid embodiment, 1 part by weight per hundered monomer of di-tert-butyl peroxide has been found useful.
Once the reaction product exits the CTR, it is devolatilized to separate the molten acrylic resin, which can be flaked or pelletized after cooling. This then can be used to prepare dispersions. A typical formula would be prepared as follows:
Charge #1 is 201.52 g acrylic resin, 102.16 g de-ionized (DI) water, 4.99 g Dowfax 2A1 and 5.17 g Triton X-100 surfactant; adjust to a pH of 8.71 with ca. 3 g ammonium hydroxide.
Charge #2 is 146.58 g styrene and 27.60 g 2-ethylhexylacrylate.
Charge #3 is 1.99 g ammonium persulfate and 5.30 g DI water.
Charge #4 is 1.24 g t-butyl hydroperoxide (70%).
Charge #5 is 0.70 g sodium ascorbate and 8.00 g DI water.
At t=0 min., T=23° C., apply a nitrogen blanket, charge #1 and start heating. Note that the reactor is blanketed with nitrogen to quench any free radicals present; nitrogen is not involved in the actual resin chemistry in any way.
At 38 min. 80° C., charge 16.79 g #2.
At 43 min., 82° C., charge #3.
At 53 min., 85° C., start monomer #2.
At 118 min., 84° C., complete addition of monomer #2.
At 183 min., 84° C., charge #4 and 1/3 of #5.
At 188 min., 84° C., charge 1/3 of #5.
At 193 min., 84° C., charge remainder of #5.
At 198 min., remove and allow to cool.
Normally, the above would be augmented with preservatives, dyes, pigments, thixotropes, perfumes, wetting agents, antifoams, coalescing agents, slip aids and the like prior to use.
Examples 1 through 10 explore variations of the reaction parameters, particularly pressure, on the percent conversion (one-pass yield) and the properties of coatings made from dispersions prepared from the acrylic resins produced by the CTR. Example 11 describes a preferred embodiment, wherein the monomers are recycled and surprisingly form a product not only better than that had from virgin monomers, with respect to gloss on white, but also superior to the nearest commercial equivalent, Joncryl 678. Joncryl's properties as a control are shown in example 1. Example 12 shows the effect of varying monomer ratios on the yield obtained, as well as the highest yield obtained. All percents are weight percents and all molecular weights are weight average.
EXAMPLE 1
29.1% styrene, 40.9% α-methyl styrene, 29.5% acrylic acid and 0.5% di-tertiary butyl peroxide (the "feedstock") was passed through a continuous tube reactor. The residence time was 200 seconds, the pressure was 140 psig and the temperature was 232° C. (450° F.). The conversion was 77.6%. The acrylic resin/unreacted monomer blend was devolatilized. The resulting resin had a weight average molecular weight of 7913, an acid value of 253 and a glass transition temperature (Tg) of 117° C. A control sample of Joncryl 678 (trademark, S. C. Johnson Co.) was measured and found to have a weight average molecular weight of 9000, an acid value of 224 and a glass transition temperature (Tg) of 117° C. The composition of Joncryl 678 is believed to be 30% styrene, 40% α-methyl styrene and 30% acrylic acid. A dispersion was made from the experimental resin by the technique described above but neutralizing to pH 9.32. The final dispersion was 49.02% solids. Its viscosity was 530 cps, the particle size was 94.1 nm, while the gloss on black was 91.3 and the gloss on white was 82. The coatings were evaluated for gloss by conventional means, i.e. simply measuring within a Macbeth Novo-Gloss meter the visible light reflected from the surface at the same angle (i.e. 60 degrees) as the incident angle of the light. The values expressed are for an average of several measurements. A similar dispersion made from the Joncryl 678 to 49.13% solids and a pH of 8.40. The dispersion had a viscosity of 340 cps, a particle size of 55.7 nm, gloss on black of 92.0 and a gloss on white of 102.0.
EXAMPLE 2
The same feedstock was used as in experiment 1. The residence time was 250 seconds, the pressure was 150 psig and the temperature was 238° C. (460° F.). The conversion was 81.8%. The resulting resin had a weight average molecular weight of 7582, an acid value of 249 and a glass transition temperature (Tg) of 114° C. The dispersion was made as above, neutralized to pH 9.34. The final dispersion was 49.98% solids. Its viscosity was 510 cps, the particle size was 83.2 nm, while the gloss on black was 95.8 and the gloss on white was 75.1.
EXAMPLE 3
The same feedstock was used as in experiment 1. The residence time was 150 seconds, the pressure was 130 psig and the temperature was 238° C. (460° F.). The conversion was 61.8%. The resulting resin had a weight average molecular weight of 8098, an acid value of 255 and a glass transition temperature (Tg) of 127° C. The dispersion was made as above, neutralized to pH 9.10. The final dispersion was 49.48% solids. Its viscosity was 875 cps, the particle size was 74.5 nm, while the gloss on black was 93.5 and the gloss on white was 94.6.
EXAMPLE 4
The same feedstock was used as in experiment 1. The residence time was 250 seconds, the pressure was 130 psig and the temperature was 238° C. (460° F.). The conversion was 75.4%. The resulting resin had a weight average molecular weight of 8096, an acid value of 254 and a glass transition temperature (Tg) of 120.57° C. The dispersion was made as above, neutralized to pH 9.34. The final dispersion was 49.98% solids. Its viscosity was 440 cps, the particle size was 90.1 nm, while the gloss on black was 93.5 and the gloss on white was 75.0.
EXAMPLE 5
The same feedstock was used as in experiment 1. The residence time was 150 seconds, the pressure was 150 psig and the temperature was 238° C. (460° F.). The conversion was 65.9%. The resulting resin had a weight average molecular weight of 7518, an acid value of 257 and a glass transition temperature (Tg) of 124° C. The dispersion was made as above, neutralized to pH 9.48. The final dispersion was 51.24% solids. Its viscosity was 1350 cps, the particle size was 65 nm, while the gloss on black was 95.8 and the gloss on white was 71.6.
EXAMPLE 6
The same feedstock was used as in experiment 1. The residence time was 250 seconds, the pressure was 130 psig and the temperature was 227° C. (440° F.). The conversion was 82%. The resulting resin had a weight average molecular weight of 8339, an acid value of 250 and a glass transition temperature (Tg) of 128° C. The dispersion was made as above, neutralized to pH 8.70. The final dispersion was 47.85% solids. Its viscosity was 303 cps, the particle size was 71.9 nm, while the gloss on black was 95.1 and the gloss on white was 88.6.
EXAMPLE 7
The same feedstock was used as in experiment 1. The residence time was 150 seconds, the pressure was 150 psig and the temperature was 227° C. (440° F.). The conversion was 72.2%. The resulting resin had a weight average molecular weight of 7093, an acid value of 256 and a glass transition temperature (Tg) of 118° C. The dispersion was made as above, neutralized to pH 8.44 The final dispersion was 50.38% solids. Its viscosity was 535 cps, the particle size was 65.0 nm, while the gloss on black was 95.1 and the gloss on white was 85.9.
EXAMPLE 8
The same feedstock was used as in experiment 1. The residence time was 250 seconds, the pressure was 150 psig and the temperature was 227° C. (440° F.). The conversion was 86.4%. The resulting resin had a weight average molecular weight of 7809, an acid value of 249 and a glass transition temperature (Tg) of 111° C. The dispersion was made as above, neutralized to pH 8.35. The final dispersion was 48.61% solids. Its viscosity was 323 cps, the particle size was 79.6 nm, while the gloss on black was 94.8 and the gloss on white was 76.0.
EXAMPLE 9
The same feedstock was used as in experiment 1. The residence time was 150 seconds, the pressure was 130 psig and the temperature was 227° C. (440° F.). The conversion was 65.0%. The resulting resin had a weight average molecular weight of 7783, an acid value of 258 and a glass transition temperature (Tg) of 25° C. The dispersion was made as above, neutralized to pH 8.49. The final dispersion was 48.85% solids. Its viscosity was 595 cps, the particle size was 65.5 nm, while the gloss on black was 92.5 and the gloss on white was 99.5.
EXAMPLE 10
The same feedstock was used as in experiment 1. The residence time was 200 seconds, the pressure was 140 psig and the temperature was 232° C. (450° F.). The conversion was 75.4%. The resulting resin had a weight average molecular weight of 7944, an acid value of 253 and a glass transition temperature (Tg) of 114° C. The dispersion was made as above, neutralized to pH 8.54. The final dispersion was 49.15% solids. Its viscosity was 475 cps, the particle size was 72.9 nm, while the gloss on black was 95.6 and the gloss on white was 86.0.
EXAMPLE 11
The feedstock used was 90% that of experiment 1, plus 10% of the monomers recycled from the devolatilization step. The residence time was 150 seconds, the pressure was 130 psig and the temperature was 216° C. (420° F.). The conversion was 69.7%. A cut at the beginning of the run and again at the end of the run was taken. The resulting resin from one cut had a weight average molecular weight of 7913, an acid value of 253 and a glass transition temperature (Tg) of 117° C. The dispersion was made as above, neutralized to pH 8.48. The final dispersion was 48.00% solids. Its viscosity was 720 cps, the particle size was 66.6 nm, while the gloss on black was 91.92 and the gloss on white was 101.83. Note that the resin made with recycled monomers resulted in significantly higher gloss on white than that made with neat feedstock.
The resulting resin made from the other cut had a weight average molecular weight of 7582, an acid value of 249 and a glass transition temperature (Tg) of 114° C. The dispersion was made as above, neutralized to pH 8.13. The final dispersion was 48.30% solids. Its viscosity was 385 cps, the particle size was 75.5 nm, while the gloss on black was 93.24 and the gloss on white was 106.33. Note that the resin made with recycled monomers resulted in significantly higher gloss on white than that made with neat feedstock. Note also that the gloss on white, as well as the gloss on black, is superior to that obtained with the closest commercial equivalent, Joncryl 678.
EXAMPLE 12
The monomer portion of the feedstock consisted of 30% α-methyl styrene, while the ratio of acrylic acid:styrene (AA:Styrene) of the balance of the monomer was varied. Reactor pressure was 220 psig, while the residence time was 240 seconds and the heat transfer fluid temperature was 246° C. (475° F.). The results were:
______________________________________AA:Styrene Tg (° C.) Acid value Mol. Wt. % Conversion______________________________________1.31 95 292 1910 811.17 89 261 1940 841.05 94 265 1923 850.93 90 246 1899 760.83 93 242 1930 91______________________________________
EXAMPLE 13
The reaction conditions for this, and the remaining examples, are a reaction temperature of 410° F., a hot oil temperature set at 440° F. and pressure of 120 psig and a residence time of 3.3 minutes. Conversion was greater than 90% for this and the following examples. Styrene:acrylic acid:methacrylic acid was run at a 1:2:1 molar ratio (31.1:43.2:25.7 weight ratio) with 1 part by weight di-tert-butyl peroxide as the feedstock. The resulting polymer had a Tg of 112° C., a softening point of 162° C., a theoretical AV of 500, an experimental AV of 395, 1.6% residual monomer and a molecular weight of 10,000. A dispersion of the above resin was prepared by using 2 times the theoretical ammonia and then boiling off excess ammonia to pH 8-8.5 and adding DI water to compensate for loss.
EXAMPLE 14
Styrene:acrylic acid:methacrylic acid was run at a 1:3:1 molar ratio (25.6:53.2:21.2 weight ratio) with 1 part by weight di-tert-butyl peroxide as the feedstock. The resulting polymer had a Tg of 129° C., an experimental AV of 372, 5.06% residual monomer and a molecular weight of 10,400.
EXAMPLE 15
Styrene:acrylic acid:methacrylic acid was run at a 1:1:1 molar ratio (39.7:27.5:32.8 weight ratio) with 1 part by weight di-tert-butyl peroxide as the feedstock.
Although various embodiments of the invention are shown and described herein, they are not meant to be limiting, those of skill in the art may recognize various modifications to the embodiments, which modifications are meant to be covered by the spirit and scope of the appended claims. | Described is a process for making acrylic resins suitable as polymeric surfactants used in emulsion polymerization, as pigment grinding resins and for preparing dispersions used as overprint varnishes. The feedstock is styrene, α-methyl styrene, acrylic acid and a polymerization initiator and is preferably free of solvent. This mix is passed through a continuous tube reactor run at a controlled range of pressure and relatively low residence time and temperature. Optimally, when the polymer/unreacted monomers blend exits the reactor and is devolatilized, the recovered monomers are used to make up part of the feedstock. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method of using antibodies to treat pathological processes associated with proliferative diseases, such as cancer, by promoting the process of apoptosis. The invention more specifically relates to methods for the use of antibodies directed toward IL-6, including specified portions or variants, specific for at least one Interleukin-6 (IL-6 also known as interferon β2)) protein or fragment thereof in combination with steroids for the treatment of proliferative diseases such as cancer which are amenable to treatment by apoptosis inducing agents.
[0003] 2. Background
[0004] The need to develop more effective and less toxic therapeutic regiments to treat malignant diseases is becoming a major focus of cancer research. Specific factors such as cytokines that are either produced by the tumor cells or present in the tumor environment can contribute to both tumor growth and resistance to standard therapy. Targeted therapy using monoclonal antibodies towards those factors or towards specific receptors expressed by tumor cells might be the most effective way to treat cancer. Monoclonal antibodies have become the most rapidly expanding class of pharmaceuticals for treating a wide variety of human diseases, including cancer. Although antibodies have yet to achieve the ultimate goal of curing cancer, many innovative approaches stand poised to improve the efficacy of antibody-based therapies. (Carter Nature Rev Cancer (1) 118-29, 2001.
[0005] Cytokine IL-6
[0006] IL-6 (interleukin 6) is a 22-27 kDa secreted glycoprotein formerly known as monocyte-derived human B-cell growth factor, B-cell stimulatory factor 2, BSF-2, interferon beta-2, and hybridoma growth factor, which has growth stimulatory and proinflammatory activities (Hirano et al. Nature 324: 73-76, 1986).
[0007] IL-6 belongs to the granulocyte colony-stimulating factor (G-CSF) and myelomonocytic growth factor (MGF) family which includes leukemia inhibitory factor (LIF), oncostatin M (OSM), ciliary neurotropic factor (CNTF), cardiotropin-1 (CT-1), IL-1, and IL-11. IL-6 is produced by an array of cell types, most notably antigen presenting cells, T cells and B cells. IL-6-type cytokines all act via receptor complexes containing a common signal transducing protein, gp130 (formerly IL-6Rbeta). However, whereas IL-6, IL-11, CT-1, and CNTF bind first to specific receptor proteins which subsequently associate with gp130, LIF and OSM bind directly to a complex of LIF-R and gp130. The specific IL-6 receptor (IL-6R or IL-6alpha, gp80, or CD126) exists in either membrane bound or soluble forms (slL-6R, a 55 kD form), which are both capable of activating gp130.
[0008] Several agents are known to induce the expression of IL-6 including IL-1, IL-2, TNFα, IL-4, IFNα, oncostatin and LPS. IL-6 is involved in diverse activities such as B and T cell activation, hematopoiesis, osteoclast activity, keratinocyte growth, acute phase protein synthesis, neuronal growth and hepatocyte activation (Hirano et al. Int. Rev. Immunol;16(3-4):249-84, 1998).
[0009] Although IL-6 is involved in many pathways, IL-6 knockout mice have a normal phenotype, they are viable and fertile, and show slightly decreased number of T cells and decreased acute phase protein response to tissue injury (Kopf M et al. Nature: 368:339-42, 1994). In contrast, transgenic mice that over-express cerebral IL-6 develop neurologic disease such as neurodegeneration, astrocytosis, cerebral angiogenesis, and these mice do not develop a blood brain barrier (Campbell et al. PNAS 90: 10061-10065, 1993).
[0010] The Role of IL-6 in Cancer
[0011] IL-6 is implicated in the pathophysiology of several malignant diseases by a variety of mechanisms. IL-6 is hypothesized to be a causative factor in cancer-related morbidity such as asthenia, cachexia and bone resorption. Tumor-induced cachexia (Cahlin et al. (2000) Cancer Res; 60(19):5488-9), bone resorption and associated hypercalcemia were found to be diminished in IL-6 knockout mice (Sandhu et al. 1999). Cancer-associated depression, and cerebral edema secondary to brain tumors have also been associated with high levels of IL-6 (Musselman et al. Am J Psychiatry.;158(8):1252-7, 2001).
[0012] Experimental results from a number of in vitro and in vivo models of various human cancers have demonstrated that IL-6 is a therapeutic target for inhibition. IL-6 can induce proliferation, differentiation and survival of tumor cells, promote apoptosis (Jee et al. Oncogene 20: 198-208,2001), and induce resistance to chemotherapy (Conze et al. Cancer Res 61: 8851-8858, 2001).
[0013] Multiple myeloma is malignancy involving plasma cells. IL-6 is known to enhance proliferation, differentiation and survival of malignant plasma cells in multiple myeloma (MM) through an autocrine or a paracrine mechanism that involves the inhibition of apoptosis of the malignant cells. Accordingly, blocking of IL-6 has been postulated to be an effective therapy (Anderson et al. Hematology:147-165, 2000). Both in vitro experiments (Tassone, P. et al. Int. J. Oncol. 21(4): 867-873, 2002) and clinical trials have been performed (Bataille et al. (1995) Blood; 86(2):685-91 and Van Zaanen, et al. (1996) J Clin Invest 98: 1441-1448) and the results indicate that IL6 blockade has demonstrable effect on cancer cell growth.
[0014] Specific factors such as cytokines that are either produced by the tumor cells or present in the tumor environment can contribute to both tumor growth and resistance to standard therapy. Cytokines, such as IL-6, that bind to cell surface receptors and either modulate the immune response or inhibit some of the death signaling domains, render the cells resistant to steroids or chemotherapy induced cell death (Fehniger et al., Cytokine Growth Factor Rev 13:169-83, 2002).
[0015] Steroids Induce Apoptosis
[0016] Apoptosis is a form of programmed cell death that occurs under numerous developmental and physiological conditions that require the selective elimination of cells from tissues and organs without the production of an inflammatory response. The initiation of apoptosis is controlled bythe balance between death and life signals perceived by the cell. The apoptotic response by cells perceiving a death stimulus includes: a reduction in cell volume, compaction of intracellular organelles, chromatin condensation, and the generation of apoptotic bodies which contain degraded cellular components. This mode of death is in contrast to lytic mechanisms which releases cell contents into the surrounding environment. Apoptotic bodies are often engulfed by neighboring cells or macrophages, preventing the occurrence of an inflammatory response in the region of the dying cells.
[0017] Dexamethasone, a steroid drug, is a catabolic effector molecule that initiates the apoptotic process and causes what is termed glucocorticoid-induced apoptosis in rodent and human lymphocytes. These cells respond to dexamethasone with cell growth arrest, chromatin condensation, cell shrinkage, and the selective degradation of DNA, RNA, and protein. The response is dependent on the presence of functional glucocorticoid receptors and requires gene expression. The fragmentation of DNA and its associated cell shrinkage is an irreversible commitment to cell death (Cidlowski et al., Recent Prog Horm Res (51) 457-90, 1996).
[0018] Monoclonal Antibodies to IL-6
[0019] Murine monocolonal antibodies to IL-6 are known as in, for example, U.S. Pat. No. 5,618,700. U.S. Pat. No. 5,856,135 discloses reshaped human antibodies to human IL-6 derived from a mouse monoclonal antibody SK2 in which the complementary determining regions (CDR's) from the variable region of the mouse antibody SK2 are transplanted into the variable region of a human antibody and joined to the constant region of a human antibody.
[0020] Another murine IL-6 monoclonal antibody referred to as CLB-6/8 capable of inhibiting receptor signaling was reported (Brakenhoff et al, J. Immunol. (1990) (145:561). A chimerized form of this antibody called cCLB8 was constructed (Centocor, Malvern, Pa.) and has been given to multiple myeloma patients (Van Zaanen, et al. 1996 supra). The chimerized antibody and the method of making the resulting antibody from the murine antigen binding domains has been fully described in the applicants' copending application U.S. Ser. No. 60/332,743 hereby incorporated by reference into the present application.
[0021] Analysis of patient serum samples prior to and after cCLB8 administration showed that circulating levels of both sIL6R and sgp130 were high in these patients and remained unchanged by the treatment despite total blockage of serum IL-6 activity (VanZaanen, et al. Leukemia Lymphoma 31(506): 551-558, 1998.)
[0022] B-E8 is a murine mAb to IL-6 manufactured by Diaclone, France which has also undergone clinical evaluation. B-E8 mAb demonstrated effectiveness in treating B-lymphoproliferative disorders (Haddad et al 2001). In AIDS associated lymphoma, this anti-IL-6 mAb had a clear effect on lowering lymphoma-associated fever and loss of weight due to cachexia, thereby improving indices of the quality of life for those patients (Emilie et al. (1994) Blood 84(8):2472-9). B-E8 has also been us renal carcinoma patients. Metastatic renal cell carcinoma (RCC) is frequently associated with high levels of IL-6 and it is accompanied by paraneoplastic symptoms. B-E8 treatment had a significant reduction in the paraneoplastic syndrome in three RCC patients (Blay et al., Int J Cancer; 72(3): 424-30, 1997). In another published clinical trial, six patients with RCC were treated with B-E8 (Legouffe et al. (1994) Clin Exp Immunol. 98(2): 323-9). All of the treated patients demonstrated a loss of symptoms generally attributable to IL-6 overproduction following B-E8 treatment.
[0023] The clinical experience with anti-IL6 Mabs has been limited to date. However, several in vitro and murine models of various human tumors have been used to demonstrate that anti-IL-6 Mabs have the potential to impact tumor cell survival and disease progression including: inhibiting growth of human brain tumor cells (Goswami et al. (1998) J Neurochem 71: 1837-1845) or tumors (Mauray et al. 2000), human renal carcinoma tumors and serum calcium concentrations (Weisglass et al. (1995) Endocrinology 138(5):1879-8), and human hormone refractory prostate tumor xenografts (Smith et al. (2001) Prostate; 48(1):47-53). In one reported case, (B. Klein et al, Blood, 78: 1198-1204 (1991), a patient with plasma cell leukemia who had been treated unsuccessfully with cytotoxic chemotherapy (VAD regimen), was treated with anti-IL-6 therapy followed by treatment with dexamethasone to limit the effects of a putative immunization. The anti-IL-6 Mabs blocked myeloma cell proliferation in vivo for 45 days.
[0024] In summary, IL-6 is a pleiotropic cytokine that can promote the pathogenesis of malignant diseases through several mechanisms. Preclinical data have shown that IL-6 is a survival, proliferation and differentiation factor in several types of tumors including renal cancer and prostate cancer. IL-6 also plays a major role in development of cancer related morbidity such as cachexia, bone resorption and depression and it can cause resistance to chemotherapy by inducing MDR1 gene expression. Clinical data have shown that elevated levels of IL-6 contribute to the malignant process in several diseases and preliminary clinical trials have shown some disease attenuating activity of anti-IL-6 Mabs.
[0025] There is a need for agents capable of limiting the growth, survival, and metastatic potential of tumor cells, particularly renal carcinoma and hormone refractory prostate carcinoma. Apoptosis describes a particular sequence of events which eliminates viable cells from a tissue. The induction of apoptosis, therefore, in tumor tissue is desirable in so far as it reduces the tumor mass while preventing the release of tumor derived toxins which contribute to cancer related side effects. While steroid drugs promote apoptosis, IL6 protects against apoptosis specifically of cancer cells.
[0026] Therefore, it would be extremely desirable to have cancer treatment regimens that both induce apoptosis of unwanted pathogenic cells, such as malignant cells, and provide protection against the undesirable effects of excess IL-6 on tumor growth and resistance to apoptotic and other chemotherapy agents while at the same time ameliorating the ancillary and detrimental effects of excess endogenously produced IL-6 on the host such as asthenia, cachexia, and bone resorption.
SUMMARY OF THE INVENTION
[0027] This invention is a method of treating proliferative diseases amenable to treatment by apoptosis inducing agents in a patient in need of such treatment, which comprises co-administering an agent capable of inducing apoptosis and an IL-6 antagonist. In a preferred embodiment the apoptotic agent is a corticosteroid, most preferably dexamethasone, and the IL-6 antagonist is a monoclonal antibody specific for IL-6.
[0028] In one aspect, the IL-6 antagonist is an anti-IL-6 antibody. In this respect, the invention relates to a method of using antibodies directed toward IL-6, including specified portions or variants, specific for at least one Interleukin-6 (IL-6 also known as Interferon β2)) protein or fragment thereof, to augment the therapeutic effect of corticosteroid therapy. Such anti-IL-6 antibodies can act through their ability to prevent the interaction of IL-6 with membrane bound receptor in a manner that prevents events associated with the initiation or progression of cancer tissue including events leading to enhanced tumor cell survival, tumor growth, and metastatic spread. In a particular embodiment, the anti-IL-6 antibody used in combination with the steroid is one that specifically binds IL-6 in a manner that prevents its action systemically and locally. The antibodies may bind to IL6 creating a long-lived complex incapable of activating membrane bound receptor, such as gp130, in any tissue accessible by the complex through normal circulatory mechanisms. The method of the present invention thus employs antibodies having the desirable neutralizing property which makes them ideally suited for therapeutic and preventative treatment of metastatic disease states associated with various forms of cancer in human or nonhuman patients.
[0029] Accordingly, the present invention is directed to a method of treating a disease or condition which as a component involves the prolonged survival of unwanted cell types, such as malignant cells, in a patient in need of such treatment which comprises administering to the patient an amount of a neutralizing IL-6 antibody to enhance apoptosis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] [0030]FIG. 1A-C. Scatter diagrams showing the data points for Tdt+ RPMI 8662 cells (terminal deoxynucleotidylexotransferase)-mediated dUTP-FITC nick end labeled) which represent cells actively undergoing apoptosis when treated with dexamethasone.
[0031] [0031]FIG. 1A shows the level of apoptosis (45%) in a representative experiment for cells treated with dexamethasone. FIG. 1B shows the level of apoptosis (20%) when IL-6 is added to cells treated with the same concentration of dexamethasone as in 1 A. FIG. 1C shows the level of apoptosis (60%) in cells treated with dexamethasone and IL6 as in 1 B but where anti-IL6 antibody is also present.
DETAILED DESCRIPTION OF THE INVENTION
[0032] Two types of steroid hormones are synthesized in the adrenal cortex: corticosteroids and androgens. Corticosteroids (glucocorticoids and mineralocorticoids) are catabolic while the androgens are generally anabolic. Glucocorticoids, as represented by hydrocortisone, are so-named because of their role in regulating carbohydrate-metabolism. Mineralcorticords, as represented by aldosterone, regulate electrolyte balance. In addition to these functions, corticosteroids afford the individual (human or animal) the ability to cope with stressful environmental conditions or noxious stimuli. The daily output of corticosteroids by the adrenals can rise as much as 10-fold in response to stress. Therefore, the pharmacological agents that are corticosteroid analogs have therapeutic effects that are the side effects on physiological processes of the natural regulators of metabolic processes. For example, the anti-inflammatory and immunosuppressive actions of corticosteroids are one of the major therapeutic uses of drugs that mimic glucocorticoids, such as prednisone or dexamethasone. As understood herein, the term “steroid” refers to glucocorticoids or therapeutic agents which are analogs of or mimetics of glucocorticoids.
[0033] The understanding of the all the interactions that lead to lymphocytopenia in some situations and increased production of lymphoid tissue on the other hand in response to elevated or exogenous steroid is still incomplete. However, it is common practice to give steroids in the course of treating lymphoid malignancies. Likewise, suppression of inflammation is of enormous clinical benefit in a variety of instances as is the immunosuppressive effect of steroids. Steroids block or inhibit production and release of prostaglandins and leukotrienes, as well as the inflammatory cytokines; IL-1, IL-6, and TNFalpha, and acute phase reactants from macrophages and monocytes, endothelial cells, and fibroblasts. In addition, steroids reduce the elaboration of surface adhesion molecules on endothelial cells, the release of histamine by basophils, and the release of additional cytokines (IL-2, IL-3, and IFNgamma) from lymphocytes and suppress growth factor induced proliferation of fibroblasts.
[0034] Corticosteroids inhibit the inflammatory response to a variety of inciting agents and probably delay or slow healing. They transiently inhibit the edema, fibrin deposition, capillary dilation, leukocyte migration, capillary proliferation, fibroblast proliferation, deposition of collagen, and scar formation associated with inflammation. There is no generally accepted explanation for the mechanism of action of ocular corticosteroids. However, corticosteroids are thought to act by the induction of phospholipase A2 inhibitory proteins, collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A2. Corticosteroids are capable of producing a rise in intraocular pressure.
[0035] In effect, the hypothalamic-pituitary-adrenal axis (HPA axis) communicates with the immune system and it has been suggested that the action of steroids is to protect against the life-threatening activity of the cytokine “storm” which can accompany severe infection, trauma, or cancer. As such, steroids and IL6 are on opposing sides in the balancing act.
[0036] Use of steroids is not nontoxic. The toxic effects of therapeutic use of steroids are of two categories: those resulting from the use of supraphysiological levels of the hormone and those resulting from withdrawal from the effects of these above normal levels. Both types of side effects are potentially lethal. Prolonged therapy can lead to fluid and electrolyte abnormalities, hypertension, hyperglycemia, increased susceptibility to infection, osteoporosis, myopathy, behavioral disturbances, cataracts, growth arrest, and the physiological changes including adipose redistribution and hirsutism.
[0037] The effects of steroids on bone and calcium distribution are due to decreased activity of osteoblasts, decreased Ca2+ absorption in the gut, and increased PTH production. These effects are actually compounded by the effects of IL6 which promotes osteoclast activity as well as PTH release resulting in hypercalcemia and therefore the risk of thrombotic events.
[0038] The most frequent problem with withdrawal from steroid therapy is recurrence of the underlying condition, which may include graft rejection is the case of a transplant. Other complications include acute renal insufficiency as a consequences of HPA axis suppression. Recovery from steroid withdrawal may take from weeks to a year or longer.
[0039] Besides treating adrenal insufficiency syndromes and post-menopausal estrogen loss, estrogen loss due to ovariectomy or total hysterectomy, steroid therapy may be administered to treat non-endocrine disorders which are immune-mediated or require control of inflammatory mediators such as rheumatic disorders, renal diseases, allergic disease, bronchial asthma, ocular diseases, skin diseases, gastrointestinal diseases, hepatic diseases, malignancies, cerebral edema (due to parasites or neoplasms), hemolytic anemias, and stroke and spinal cord injury.
[0040] Other conditions or diseases wherein steroid therapy is used are exemplified by, but not limited to adrenal hyperplasia, adrenocortical insufficiency, alopecia areata, acquired hemolytic anemia, hypoplastic anemia (congenital), ankylosing spondylitis , gouty and psoriatic arthritis, berylliosis, bronchial asthma, bursitis, allergic and vernal conjunctivitis, cerebral palsy, chorioretinitis, choroiditis, chronic obstructive lung disease, ulcerative colitis, collagen disease, allergic conjunctivitis and corneal marginal ulcers, atopic and contact dermatitis, herpetiformis bullous dermatitis, seborrhea, edema due to lupus erythematosus, lupus nephritis, cerebral edema, regional enteritis, epicondylitis, erythroblastopenia, granuloma annulare, herpes zoster ophthalmicus, inflammation of the eye including iridocyclitis, iritis, keloids, keratitis, laryngeal edema, lichen planus, lichen simplex chronicus, Loeffler's syndrome, lupus erythematosus discoides, lupus erythematosus, systemic, meningitis, tuberculous, myositis, mycosis fungoides, necrobiosis lipoidica diabeticorum, nephrotic/nephritic syndrome, anti-glomerular basement membrane nephritis, ophthalmia, optic neuritis, synovitis of osteoarthritis, pemphigus, psoriatic, idiopathic thrombocytopenic purpura, rheumatic carditis, rheumatoid arthritis, rheumatoid arthritis, chronic rhinitis, sarcoidosis, scleroderma, serum sickness, shock, Stevens-Johnson syndrome, tenosynovitis, takayasuds arteritis, Wegener's granulomatosis, acute nonspecific thrombocytopenia, thyroiditis, trichinosis with myocardial involvement, trichinosis with neurologic involvement, tuberculosis, urticaria, uveitis.
[0041] Steroid therapy may also be used in conjunction with an organ or tissue transplant, such as a bone marrow transplant or a multiple organ transplant. In certain aspects of the invention, the steroid is administered at a high dose and/or over a long period of time.
[0042] Cancers arising from immune cell abnormalities are commonly treated with steroid drugs. These include myeloid cancers such as multiple myeloma, and myelogenous leukemia (CML), as well as lymphocytic leukemia (CLL and ALL) and lymphomas, particularly Non-Hodgkin's Lymphoma (NHL). Other cancers forming solid tumors including prostate, and breast cancers can be treated with the method of the present invention and, due to its minimally toxic nature, in combination with other agents and where adjunctive forms of therapy are being practiced, such as radiation therapy.
[0043] Other “solid tumor” forming cancers, include, but are not limited to, sarcomas and carcinomas such as fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, chordoma, angiosarcoma, endotheliosarcoma, lymphangiosarcoma, lymphangioendotheliosarcoma, synovioma, mesothelioma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma, colon carcinoma, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal cell carcinoma, adenocarcinoma, sweat gland carcinoma, sebaceous gland carcinoma, papillary carcinoma, papillary adenocarcinomas, cystadenocarcinoma, medullary carcinoma, bronchogenic carcinoma, renal cell carcinoma, hepatoma, bile duct carcinoma, choriocarcinoma, seminoma, embryonal carcinoma, Wilm's tumor, cervical cancer, testicular tumor, non-small cell lung carcinoma, small cell lung carcinoma, bladder carcinoma, epithelial carcinoma, glioma, astrocytoma, medulloblastoma, craniopharyngioma, ependymoma, pinealoma, hemangioblastoma, acoustic neuroma, oligodendroglioma, menangioma, melanoma, neuroblastoma, retinoblastoma, pancreatic or gastric adenocarcinoma, human papilomavirus associated cervical intraepithelial neoplasia, and hepatoma.
[0044] A secondary tumor, a metastasis, is a tumor which originated in a primary site in the body and spread to a distant organ. The common routes for metastasis are direct growth into adjacent structures, spread through the vascular or lymphatic systems, and tracking along tissue planes and body cavities with, for example, peritoneal fluid or cerebrospinal fluid. Secondary hepatic tumors are one of the most common causes of death in cancer patients and are by far and away the most common form of liver tumor. Although virtually any malignancy can metastasize to the liver, tumors which are most likely to spread to the liver include: cancer of the stomach, colon, and pancreas; melanoma; tumors of the lung, oropharynx, and bladder; Hodgkin's and non-Hodgkin's lymphoma; tumors of the breast, ovary, and prostate. Secondary lung, brain, and bone tumors are common to advanced stage breast, prostate and lung cancers. Any cancer may metastasize to bone, but metastases from carcinomas are the most common, particularly those arising in the breast, lung, prostate, kidney, and thyroid. Carcinoma of the lung is very commonly accompanied by hematogenous metastatic spread to the liver, brain, adrenals, and bone and may occur early, resulting in symptoms at those sites before obvious pulmonary symptom. Metastases to the lungs are common from primary cancers of the breast, colon, prostate, kidney, thyroid, stomach, cervix, rectum, testis, and bone and from melanoma. Each one of the above-named secondary tumors may be treated by the antibodies of the present invention.
[0045] Bone Loss
[0046] Bone loss is associated with and/or caused by steroid therapy as are high levels of circulating IL6 in cancer patients. In addition to bone loss due to aging and estrogen deficiency, patients of all ages, both sexes, and all races are susceptible to steroid-induced bone loss. Administration of glucocorticoids and steroids is the third most common cause of osteoporosis. Steroid-induced bone loss usually affects the cortical and cancellous bone of the axial skeleton. Between 30% and 50% of individuals taking steroids for more than 6 months will develop osteoporosis. The rate of bone loss is very rapid in the initial year of therapy, with as much as 20% of the bone lost in the first year. Doses exceeding 7.5 mg/day of prednisone can cause significant loss of trabecular bone in most people.
[0047] Studies in mice administered glucocorticoids suggests that steroid- induced bone loss is due to decreased bone formation which results from higher numbers of apoptotic/dead osteoclasts and osteoblasts. Lesser numbers of these cells could account for changes seen with glucocorticoid-induced bone disease. A decrease in osteoblast and osteocyte cell number due to death/apoptosis has also been demonstrated in patients who have glucocorticoid-induced osteoporosis (Weinstein et al., 1998).
[0048] Despite the current understanding and the considerable amount of research in this area, bone loss and osteoporosis remain significant medical and economic problems. Therefore, methods of reducing or preventing bone loss, for example by reducing or preventing apoptosis of osteocytes and osteoblasts, would represent a significant advance in the art.
[0049] Thus a particularly advantageous aspect of the present invention is to allow the treatment of disease with steroid therapy while preventing or ameliorating the effects on bone, such as bone resorption and concomitant hypercalcemia.
[0050] Methods of Evaluating Apoptotic Activity
[0051] Many events occur during the process of apoptosis that can be assayed to determine if cells are undergoing apoptosis and/or the extent of apoptosis. Nuclear matrix proteins (NMP) have been shown to dissociate and solubilize during apoptosis, which likely accounts for certain morphological changes seen in the nucleus of an apoptotic cell. Thus, detection of release of one or more NMP, particularly in a degraded state, such as lamin, can be used to assess apoptosis. Morphological measurements related to loss of nuclear structure and chromosome condensation into discrete balls are other markers of apoptosis. Degradation of the DNA produces 180 to 200 bp fragments that can be visualized as a DNA ladder by agarose or acrylamide gel electrophoresis. These nucleosomal fragments can also be labeled radioactively, flourescently, or with enzymes that can catalyze a color producing reaction. The fragments that possess free 3′ hydroxyl groups can be labeled using terminal deoxynucleotidyl transferase, and those lacking the ternminal 3′ hydroxyl group can be labeled using the Klenow fragment of E. coli DNA polymerase I.
[0052] In addition to nuclear changes, plasma and mitochondrial membrane perturbations occur early in apoptosis. Phosphatidylserine, which is restricted to the inner surface of the plasma membrane bilayer in normal cells, is externalized to the outer plasma. Phosphatidylserine on the outer surface of the plasma membrane can be detected by annexin, which has a high affinity for phosphatidylserine (Martin et al., 1995), or by anti-phosphatidylserine antibodies. Furthermore, certain dyes that are excluded from viable cells, such as trypan blue and propidium iodide, stain apoptotic cells due to these membrane perturbations.
[0053] Release of the cytosolic enzymes such as lactate dehydrogenase or loss of mitochondrial function, such as by measuring electron transfer to a dye, MTT ([3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide] can be measured spectrophotometrically.
[0054] Among the assays currently used to monitor apoptosis, the most common are visual methods, such as light or electron microscopy to determine cellular morphology, vital dye exclusion, nuclear staining with fluorescent dyes such as propidium iodide, acridine orange, bisbenzimide (Hoechst 33258 and 33342) and green fluorescent protein (GFP), indirect methods such as fluorescence-activated cell sorting (FACS) of fluorescently labeled cells, assays for the release of the cytosolic enzyme lactate dehydrogenase, the MTT/XTT assay, detection of binding of annexin V or anti-phosphatidylserine antibodies, detection of DNA fragmentation, detection of the release of soluble nuclear matrix proteins, such as nuclear matrix protein A, from cells, detection of the loss of lamins from the nuclear envelope and detection of free nucleosomes. Additionally, in certain instances these assays are combined, such as determining the binding of annexin V or anti-phosphatidylserine antibodies in conjunction of dye exclusion, such as propidium iodide. Annexin V labeled with either FITC or biotin, as well as a monoclonal anti-phosphatidylserine antibody, are available. Kits for the labeling and detection of these DNA fragments, four monoclonal antibodies against nuclear matrix proteins, as well as a kit for detecting soluble nuclear matrix proteins, anti-laminin antibodies are available, as are kits for detecting free nucleosomes. Many of these reagents are available commercially from Oncogene Research Products (Cambridge, Mass.).
[0055] Steroid Compositions
[0056] Synthetic analogs of glucocorticoids or preparation of hydrocortisone are available commercially under the names: cortisone acetate, dexamethasone, methylprednisolone acetate, prednisone, hydrocortisone, or prednisolone. Preparations containing these active ingredients are available from various vendors and are commonly administered to cancer patients intravenously or taken orally in tablet form. Triamcinolone acetonide is a derivative of triamcinolone (Muro Pharmaceuticals) approximately eight times more potent than prednisone in animal models of inflammation and is available as an intranasal spray. Loteprednol etabonate is structurally similar to other corticosteroids but the number 20 position ketone group is absent and is used preferentially in occular indications. Medrysone is a synthetic corticosteroid with topical anti-inflammatory and anti-allergic activity. Alclometasone dipropionate, betamethasone, mometasone furoate, halobetasol propionate, fluocinolone acetonide, and flurandrenolide are synthetic corticosteroids (typically fluorinated derivatives) particularly preferred for dermatological applications that can be topically administered. Compositions comprising any of the aforementioned active agents are encompassed by the present invention.
[0057] IL-6 Antagonists
[0058] As used herein, the term “IL-6 antagonists” refers to a substance which inhibits or neutralizes the angiogenic activity of IL-6. Such antagonists accomplish this effect in a variety of ways. One class of IL-6 antagonists will bind to IL-6 protein with sufficient affinity and specificity to neutralize the angiogenic effect of IL-6. Included in this class of molecules are antibodies and antibody fragments (such as for example, F(ab) or F(ab′) 2 molecules). Another class of IL-6 antagonists are fragments of IL-6 protein, muteins or small organic molecules i.e. peptidomimetics, that will bind to IL-6, thereby inhibiting the angiogenic acitvity of IL-6. The IL-6 antagonist may be of any of these classes as long as it is a substance that inhibits IL-6 angiogenic activity. IL-6 antagonists include IL-6 antibody, IL-6R antibody, an anti-gp130 antibody or antagonist, modified IL-6 such as those disclosed in U.S. Pat. No. 5,723,120, antisense IL-6R and partial peptides of IL-6 or IL-6R.
[0059] Anti-IL-6 Antibodies and Agents
[0060] Any of the anti-IL-6 antibodies known it the art may be employed in the method of the present invention. Murine monocolonal antibodies to IL-6 are known as in, for example, U.S. Pat. No. 5,618,700 or the antibody known as B-E8 (Diaclone, France) or the antibody referred to as CLB-6/8 capable of inhibiting receptor signaling (Brakenhoff et al, J. Immunol. (1990) (145:561) may be used. To avoid immune response to the antibody which causes adverse effects as well as eliminating the therapeutic action of the antibody, it is desirable to administer a human or close to human antibody scaffold. U.S. Pat. No. 5,856,135 discloses reshaped antibodies to human IL-6 derived from a mouse monoclonal antibody SK2 in which the complementary determining regions (CDR's) from the variable region of the mouse antibody SK2 are transplanted into the variable region of a human antibody and joined to the constant region of a human antibody. A chimerized form of the murine IL-6 monoclonal of the CLB-6/8 murine antibody antibody called cCLB8 was constructed (Centocor, Leiden, The Netherlands) and has been given to multiple myeloma patients (Van Zaanen, et al. 1996 supra). The method of making the resulting antibody from the murine antigen binding domains has been fully described in the applicants' copending application U.S. Ser. No. 10/280,716, hereby incorporated by reference into the present application.
[0061] Other process for humanizing of primatizing antibodies raised in non-human species are also suitable for constructing antibodies of the present invention providing the product antibody retains its ability to block IL6 from signaling in the target cell through interaction with its cognate receptor or receptor complex.
[0062] Other agents affecting a decrease in IL-6, such as the IL-6 receptor antagonist Sant7 (Tassone et al., Int J Oncol (21) 867-873, 2002) may also be employed.
[0063] Anti-Apoptotic Combinations of Steroids and Anti-IL6 Agents
[0064] A preferred combination of the present invention uses a standard i.v. or oral steroid preparation such as dexamethosone administered to a patient in combination with a neutralizing anti-IL6 monoclonal antibody.
[0065] The neutralizing anti-IL6 monoclonal antibody described herein can be used augment and promote apoptosis in combination with naturally produced corticosteroids or with steroid drug therapy and thereby prevent or impair tumor growth and prevent or inhibit metastases. Additionally, said monoclonal antibody can be used to enhance the anti-inflammatory activity of steroid drugs in diseases amenable to such treatment.
[0066] The beneficial effects of the combination of anti-IL-6 monoclonal antibodies with steroids are seen in the tumor response, local control of primary tumor growth and the reduced incidence or rate of metastatic spread. Secondly, the response is more effective than using either of these two agents alone. This combination can be used in a vast array of diseases such as multiple myeloma and edema secondary to primary brain tumors or brain metastasis where effective treatment is yet to be developed. Combining anti-IL-6 and dexamethasone can overcome the resistance to steroid therapy and can also help in reducing the dose of steroid needed to achieve an effect which is essential in minimizing the steroid tapering process; a process necessary to inhibit disease progression and associated symptoms. Finally this combination can decrease resistance to steroids when being used in conjunction with chemotherapy. Further, the combination treatment can have a positive effect on cerebral edema. Currently, steroids are used to treat cerebral edema. Anti-IL-6 therapy could be used to enhance the effect of steroids and decrease side effects observed during steroid tapering.
[0067] It is now understood that several signal transduction pathways lead to the stimulus that activates initiation of the apoptotic process. Stimuli that activate these pathways use diverse receptors (JNK, FAS, and the steroid receptors) include ionizing radiation and ceramide in addition to glucocorticoids or analogs (Makin, G. Experts Opin. Ther. Targets 6(1): 73-84, 2002). On the other hand, it has now been demonstrated that the survival signal activated by IL6 includes SHP2 which blocks RAFTK. RAFTK is necessary for the glucocorticoid-induced signal initiating apoptosis (Chauhan, D. et al. J. Biol. Chem. 275(36): 27845-27850, 2000). Thus, the intracellular biochemical basis for at least one mechanism of IL6 antagonism of steroid mediated apoptosis can be understood.
[0068] In its broadest sense the invention includes other combinations of agents. For instance, a number of chemotherapy agents are known to induce apoptosis, these include Doxorubicin, arsenic trioxide, retinoids, staurosporin, etoposide, 5-fluorouracil, Paclitaxel, STI571 (Gleevec), Flavoprid, ionizing radiation, Trail, BCL-2 antisense and inhibitors (Makin, Expert Opin Ther Targets (6) 73-84, 2002). Farnesyl transferase inhibitors (Le Gouill et al., Leukemia (16) 1664-7, 2002) may be successfully combined with apoptosis inducing agents, provided that the toxicity profile is acceptable and not additive.
[0069] The individual to be treated may be any mammal and is preferably a primate, a companion animal which is a mammal and most preferably a human patient. The amount of monoclonal antibody administered will vary according to the purpose it is being used for and the method of administration.
[0070] The anti-IL6 antibodies of the invention of the present invention may be administered by any number of methods that result in an effect in tissue where it is desired to enhance glucocorticoid-induced apoptosis. Further, the anti-IL6 antibodies of the invention may be administered wherever access to body compartments or fluids containing IL6 is achieved. In the case of inflamed, malignant, or otherwise compromised tissues, these methods may include direct application of a formulation containing the antibodies. Such methods include intravenous administration of a liquid composition, transdermal administration of a liquid or solid formulation, oral, topical administration, or interstitial or inter-operative administration. Administration may be affect by the implantation of a device whose primary function may not be as a drug delivery vehicle as, for example, a vascular stent.
[0071] Administration may also be oral or by local injection into a tumor or tissue but generally, the monoclonal antibody is administered intravenously. Generally, the dosage range is from about 0.01 mg/kg to about 12.0 mg/kg. This may be as a bolus or as a slow or continuous infusion which may be controlled by a microprocessor controlled and programmabale pump device.
[0072] Alternatively, DNA encoding preferably a fragment of said monoclonal antibody may be isolated from hybridoma cells and administered to a mammal. The DNA may be administered in naked form or inserted into a recombinant vector, e.g., vaccinia virus in a manner which results in expression of the DNA in the cells of the patient and delivery of the antibody.
[0073] The monoclonal antibody used in the method of the present invention may be formulated by any of the established methods of formulating pharmaceutical compositions, e.g. as described in Remington's Pharmaceutical Sciences, 1985. For ease of administration, the monoclonal antibody will typically be combined with a pharmaceutically acceptable carrier. Such carriers include water, physiological saline, or oils.
[0074] Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. Except insofar as any conventional medium is incompatible with the active ingredient and its intended use, its use in any compositions is contemplated.
[0075] The formulations may be presented in unit- dose or multi-dose containers, for example, sealed ampules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example, water for injections, immediately prior to use.
[0076] Abbreviations
[0077] Abs antibodies, polyclonal or monoclonal
[0078] aV integrin subunit alpha V
[0079] b3 integrin subunit beta 3
[0080] bFGF basic fibroblast growth factor
[0081] IFN interferon
[0082] Ig immunoglobulin
[0083] IgG immunoglobulin G
[0084] IL interleukin
[0085] IL6 interleukin 6
[0086] IL-6R interleukin-6 receptor
[0087] sIL-6R soluble interleukin-6 receptor
[0088] Mab monoclonal antibody
[0089] VEGF vascular endothelial growth factor
[0090] While having described the invention in general terms, the embodiments of the invention will be further disclosed in the following examples.
EXAMPLE 1
Dexamethasone Induced Apoptosis in Multiple Myeloma Cells: Alleviation of IL-6 Mediated Inhibition Using Anti-IL-6 Antibody
[0091] Multiple myeloma is a malignant plasma cell disorder that is resistant to conventional therapeutic regimens. IL-6 is known to be a growth and differentiation factor for myeloma cells. Dexamethasone is a glucocorticoid that is part of the standard theraputic regimen for multiple myeloma. Dexamethasone has been reported to induce apoptosis in mutliple myloma cells and cell lines through induction of apoptosis.
[0092] Materials and Methods
[0093] The cell line RPMI 8226, a human multiple myeloma cell line, was purchased from ATCC (Rockville, Md.). Cells were grown and maintained according to ATCC instructions in complete RPMI medium containing 10% FBS, 1% NEAA, 1% L-glutamine and 1% sodium pyruvate.
[0094] Chimeric CLB8 (cCLB8) (Centocor, Malvern, Pa.) was used at three different concentrations in the assay. Another a chimeric human-mouse IgG, c171A, also developed at Centocor was used as a negative control antibody.
[0095] Dexamethason-Induced Apoptosis
[0096] RPMI 8226 cells (1×10 6 /mL) were incubated for 48 h at 37° C. in a 5% CO2 incubator in RPMI complete medium with or without IL-6 (100 ng/mL), Dexamethasone (1 microM), c171A control antibody (1 microg/mL), or CNTO 328 at three concentrations (1 microg/mL, 100 ng/mL, or 10 ng/mL). After the incubation, cells were harvested and the Tunel assay (Tdt-mediated dUTP-FITC nick end labeling) as disclosed in Gavrieli et al., “Identification of Programmed Cell Death in situ Via Specific Labelling of Nuclear DNA Fragmentation”, J Immunol. Cell Biology 119:493-501, 1992 was used to measure apoptosis with minor modifications. Briefly, after the 48-hour incubation described above, approximately 10 6 cells were harvested, washed twice, and fixed with 1% paraformaldehyde for 15 minutes. After washing, the cells were permeabilized with 0.1% Triton (Sigma, St. Louis, Mo.) for 5 minutes and washed twice. The labeling reaction was performed in a heating block at 37° C. for 1 hour with 0.3 nM FITC-12-dUTP (Boehringer Mannheim, Indianapolis, Ind.), 2.5 mM CoCI2, 12.5 U Tdt, and 5 microL of 5×Tdt Buffer (Boehringer Mannheim) in a total volume of 50 microL. Cells were analyzed by flow cytometry.
[0097] After completing the Tunel assay, cells were washed twice and analyzed on a FACS Calibur flow cytometer (Becton Dickinson Immunocytometry Systems, San Jose, Calif.) equipped with a 15-mW air-cooled 488-nm argon laser. Gating to exclude debris was based upon diminished forward scatter (FSC) and side scatter (SSC). A minimum of 10,000 events was collected per sample and all analyses were performed with CELLQuest software (Becton Dickinson Immunocytometry Systems, San Jose, Calif.).
[0098] Results
[0099] The results demonstrate that the combination of dexamethasone and cCLB8 is superior to treatment with either agent alone at promoting cellular apoptosis
[0100] Dexamethasone at 1 microM, induced apoptosis in RPMI 8226 after 48 hrs (FIG. 1A). Dexamethasone induced 45% of cells to undergo apoptosis. At concentrations higher than 100 ng/mL, IL-6 inhibited dexamethasone-induced apoptosis. Dexamethasone in the presence of IL-6 induced only 20% of cells to undergo apoptosis (FIG. 1B). Dexamethasone induced 60% of cells to undergo apoptosis in the presence of both IL-6 and cCLB8 (FIG. 1C).
[0101] Table 1 shows the amount of apoptosis exhibited by RPMI 8226 cells subjected to various culture conditions. CCLB8 neutralized the inhibitory effect of IL-6 on dexamethasone-induced apoptosis in a dose dependent manner (P<0.02). The data presented in this table are representative of three experiments and P values were calculated using student T test.
TABLE 1 % Apoptosis Treatment Mean ± SEM P Value DEX 10-6 % 46 ± 4 DEX + IL-6 100 pg % 27 ± 9 DEX + IL-6 + CNTO 3281 ug % 54 ± 2.5 <0.02 DEX + IL-6 + CNTO 328100 ng % 45 ± 11 <0.02 Dex + IL-6 + Control mAb % 34 ± 9 <0.04
[0102] Summary
[0103] The experiments described herein demonstrate that effect of IL6 on apoptosis can be reduced by a specific monoclonal antibody that prevents IL6 signaling through a receptor complex which includes gp130. The data demonstrate that IL-6 inhibits dexamethasone-induced apoptosis in multiple myeloma cells. This is the first report to show that the neutralizing effect of cCLB8 on IL-6 inhibition of dexamethasone-induced apoptosis can significantly inhibit tumor cell survival by enhancing glucocorticoid-induced apoptosis and the same levels of apoptosis could not be achieved using either of these agents alone. | Methods for the use of antibodies directed toward IL-6, including specified portions or variants, specific for at least one Interleukin-6 (IL-6 also known as interferon β2)) protein or fragment thereof, in combination with steroids for the treatment of proliferative diseases such as cancer which are amenable to treatment by apoptosis inducing agents. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to a trophy structure, and more particularly to a modular trophy structure designed according to the assembly of a trophy to facilitate the manufacture and assembling processes and provide a flexible application and practical use of the trophy.
BACKGROUND OF THE INVENTION
[0002] Nowadays, our life is filled up with various different activities. To recognize and encourage achievements on good result, performance and status of the activities, trophies (or label objects in other forms) become a common way for the highlights and achievements of these activities. With reference to FIG. 1 for a conventional trophy, the trophy 90 comprises a base 91 and a label object 92 , wherein a screw 921 is protruded from the bottom of the label object 92 , and a corresponding screw hole 911 is formed on the base 91 , such that the screw 921 is locked and secured into the screw hole 911 to combine the base 91 with the label object 92 to form the trophy 90 . In addition, another screw 922 is protruded from the top of the label object 92 and secured with a label object 93 to expand the content of the highlight.
[0003] Although the finished product with the aforementioned conventional trophy structure is manufactured by screwing and assembling related parts, yet it still has the following drawbacks. Since the base 91 and the label object 92 are combined by securing the screw 921 into the screw hole 911 , the screwing and assembling operations take much time and fail to meet the cost-effective requirements, and the operating process causes a greater chance of damaging the label object 92 . Obviously, such conventional trophy structure is not an ideal design. In addition, the final combination status of the base 91 and the label object 92 requires precise positions or fixing positions and does not allow any skew of the assembly, and the conventional trophy structure relates to the setting of the length of combining the screw with the screw hole. In the modularization process, various factors may cause a dislocation of the screw and the screw hole easily to result in a misaligned connection. Obviously, the conventional trophy structure requires further improvements. Therefore, it is an important subject for related manufacturers and designers to overcome the aforementioned drawbacks of the conventional trophy structure.
[0004] In view of the aforementioned drawbacks of the prior art, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a modular trophy structure in accordance with the present invention.
SUMMARY OF THE INVENTION
[0005] Therefore, it is a primary objective of the present invention to provide a modular trophy structure that can be assembled more conveniently and quickly to achieve a cost-effective manufacture.
[0006] Another objective of the present invention is to provide a modular trophy structure that makes the connection of a trophy more flexibly to improve the expandability, practicality and value of the trophy design.
[0007] A further objective of the present invention is to provide a modular trophy structure that prevents the assembling of the trophy from being skewed, dislocated, or tilted, so as to improve the overall assembling quality and the display quality of the trophy.
[0008] To achieve the aforementioned objectives, the present invention provides a modular trophy structure, comprising: a base, having a plurality of rotating slots formed thereon, and disposed in the same circumference or different circumferences of the same center; and a label object, including a label base and a figure body coupled to each other, and the label base having a plurality of rotating latch members disposed at the same circumference or different circumferences of the same center; wherein, the rotating latch member is installed at the rotating slot, and the rotating latch member is latched into the rotating slot by a rotating operation, so that the label base is combined onto the base.
[0009] Wherein, the rotating slot includes a containing slot and a rotating slot coupled to each other, and the containing slot is coupled to a side of the rotating slot a side in the same circumferential direction, and the other side of the containing slot is protruded farther towards the outside than the rotating slot, and the rotating latch member includes a disposing portion and a rotating latch portion coupled to each other, and the disposing portion is coupled vertically to a side of the rotating latch portion in the same circumferential direction, and the other side of the disposing portion is protruded to the outside farther towards the outside than the rotating latch portion.
[0010] Wherein, the rotating slot has a blocking portion formed on an outer side of the rotating slot and at a position adjacent to the containing slot, and the bottom position of the blocking portion is substantially a rotating space.
[0011] Wherein, an end of the rotating slot away from the containing slot is a rotating latch end, and the rotating latch end has a width smaller than the rotating slot.
[0012] Wherein, the corresponding combination of the rotating slot and the rotating latch member are installed at positions of the same circumference of the same center.
[0013] Wherein, the figure body further includes at least a label connecting portion and at least a label connector coupled to the label connecting portion, and a label rotary latch mechanism is installed between the label connecting portion and the label connector.
[0014] Wherein, the label rotary latch mechanism includes a plurality of rotating slots formed at the label connecting portion and a plurality of rotating latch members disposed at the label connector, and the rotating slot includes a containing slot and a rotating slot coupled to each other, and the containing slot is coupled to a side of the rotating slot in the same circumferential direction, and the other side of the containing slot is protruded farther towards the outside than the rotating slot, and the rotating latch member includes a disposing portion and a rotating latch portion coupled to each other, and the disposing portion is coupled vertically to a side of the rotating latch portion in the same circumferential direction, and the other side of the disposing portion is protruded farther towards the outside than the rotating latch portion.
[0015] Wherein, the top of the figure body further includes an expansion connecting portion, and at least one expansion member coupled to the expansion connecting portion, and the expansion member includes an expanded base and an expanded figure body, and an expanded rotating latch mechanism is installed between the expanded base and the expansion connecting portion.
[0016] Wherein, the expanded rotating latch mechanism includes a plurality of rotating latch slots formed at the expansion connecting portion and a plurality of rotating latch members disposed at the expanded base, and the rotating latch slot includes a containing slot and a rotating slot coupled to each other, and the containing slot is coupled to a side of the rotating slot in the same circumferential direction, and the other side of the containing slot is protruded farther towards the outside than the rotating slot, and the rotating latch member includes a disposing portion and a rotating latch portion coupled to each other, and the disposing portion is coupled vertically to a side of the rotating latch portion in the same circumferential direction, and the other side of the disposing portion is protruded farther towards the outside than the rotating latch portion.
[0017] Wherein, the bottom of the blocking portion further includes at least one concave latch portion, and the top of the disposing portion includes at least one convex latch portion corresponsive to the concave latch portion, and the base further includes at least one positioning recess formed thereon, and the label base includes at least one positioning protrusion member formed thereon and corresponsive to the positioning recess.
[0018] The present invention will become clearer in light of the following detailed description of an illustrative embodiment of this invention described in connection with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic view of a conventional trophy structure;
[0020] FIG. 2 is a perspective view of a modular trophy structure of the present invention;
[0021] FIG. 3 is a partial exploded view of a modular trophy structure of the present invention;
[0022] FIG. 4 is an exploded view of a modular trophy structure of the present invention;
[0023] FIG. 5 is a schematic view of operating a modular trophy structure of the present invention;
[0024] FIG. 5A is a partial cross-sectional view of assembling a modular trophy structure of the present invention;
[0025] FIG. 6A is a schematic view of assembling a modular trophy structure of the present invention;
[0026] FIG. 6B is a schematic view of assembling a modular trophy structure of the present invention; and
[0027] FIG. 6C is a schematic view of assembling a modular trophy structure of the present invention; and
[0028] FIG. 7 is a schematic view of assembling a modular trophy structure of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] With reference to FIGS. 2 and 3 for a modular trophy structure of the present invention, the modular trophy structure comprises a base body 10 and a label object 20 , and the base body 10 comprises a base 11 , and the base 11 includes a plurality of rotating slots 12 formed thereon, and the plurality of rotating slots 12 are formed at positions of the same circumference or different circumferences of the same center. In this embodiment, the base 11 includes four rotating slots 12 formed thereon and arranged at positions of the same circumference, and the rotating slot 12 includes a containing slot 121 and a rotating slot 122 coupled to (or interconnected with) each other, and the containing slot 121 is coupled to a side of the rotating slot 122 in the same circumferential direction, and the other side of the containing slot 121 is protruded farther towards the outside (with respect to the center position) than the rotating slot 122 , so that an outer side of the rotating slot 122 has a blocking portion 123 formed at a position adjacent to the containing slot 121 , and the bottom of the blocking portion 123 is a rotating space 124 (as shown in FIG. 5A ), and an end of the rotating slot 122 away from the containing slot 121 is a rotating latch end 122 A. In an appropriate embodiment, the rotating slot 122 is tapered towards the rotating latch end 122 A. In other words, the rotating latch end 122 A has a width smaller than the rotating slot 122 .
[0030] The label object 20 includes a label base 21 and a figure body 22 coupled to each other, and the bottom of the label base 21 includes a plurality of rotating latch members 23 disposed at the same circumference or different circumferences of the same center. In this embodiment, the label base 21 includes four rotating latch members 23 corresponsive to the rotating slots 122 of the bases 11 , and the four rotating latch members 23 are disposed at positions of the same circumference. The rotating latch member 23 includes a disposing portion 231 and a rotating latch portion 232 coupled to each other, and the disposing portion 231 is coupled to a side of the rotating latch portion 232 in the same circumferential direction, and the other side of the disposing portion 231 is protruded farther towards the outside (with respect to the center position) than the rotating latch portion 232 .
[0031] The plurality of rotating slots 12 of the base 11 and the plurality of rotating latch members 23 of the label base 21 constitute a rotating latch mechanism (not labeled). In other words, the rotating latch mechanism is installed between the base 11 and the label base 21 , and the rotating latch mechanism comprises a rotating slot 12 and a rotating latch member 23 . In addition, the spatial positions of the rotating slot 12 and the rotating latch member 23 may be switched. For example, the base 11 includes the rotating latch member, and the label base 21 includes the rotating slot, but the invention is not limited to such arrangement.
[0032] In FIG. 3 , the containing slot 121 has a width A, the rotating slot 122 has a width B, the disposing portion 231 has a width a, and the rotating latch portion 232 has a width b, wherein the width A is equal to or slightly greater than the width a, and the width B is equal to or slightly greater than the width b to facilitate manufacturers or users to install the rotating latch member 23 into the rotating slot 12 . In addition, the rotating slot 122 has a length greater than the length of the rotating latch portion 232 , so as to provide an operating space of moving the rotating latch portion 232 in the rotating slot 122 . Further, the corresponding rotating slots 12 and rotating latch members 23 are arranged at positions of the same circumference (with respect to the same center), so that the containing slot 121 , rotating slot 122 is disposed opposite to the disposing portion 231 and the rotating latch portion 232 , and the plurality of rotating slots 12 (or rotating latch members 23 ) are arranged at different circumferences, so as to provide a foolproof effect for the assembling and operation processes.
[0033] In FIGS. 5 and 5A , when the label base 21 and the base 11 are combined, the rotating latch member 23 is installed at the rotating slot 12 , so that the disposing portion 231 (with the width a) is installed into the containing slot 121 (with the width A), and then the rotating latch portion 232 is rotated to move in a direction towards the rotating latch end 122 A of the rotating slot 122 , until a latching effect is produced, and the disposing portion 231 is linked to move into the rotating space 124 . After the disposing portion 231 is moved to a position under the blocking portion 123 to produce a latching effect in the vertical direction, the rotation and latching effect of the rotating latch mechanism makes the label base 21 to be combined with the base 11 , so as to prevent the installation from being dislocated or skewed. If it is necessary to remove or separate the label base 21 from the base 11 , the rotating latch portion 232 is rotated in the opposite direction to resume the disposing portion 231 to its original position opposite to the containing slot 121 . Now, the label base 21 can be separated or removed from the base 11 . The assembling and removing operations are quick, simple, and easy.
[0034] The figure body 22 is the main eye-catching area of the trophy, and the figure body 22 may further include at least a label connecting portion 24 and at least a label connector 25 coupled to the label connecting portion 24 , and a label rotary latch mechanism (not labeled) may also be installed between the label connecting portion 24 and the label connector 25 . In this embodiment, the label rotary latch mechanism includes a plurality of rotating slots 241 installed at the label connecting portion 24 and a plurality of rotating latch members 251 installed at the label connector 25 , and the plurality of rotating slots 241 and the plurality of rotating latch members 251 are also arranged at the same circumference or different circumferences of the same center, and the rotating slot 241 includes a containing slot 242 and a rotating slot 243 coupled to (or interconnected with) each other, and the rotating latch member 251 includes a disposing portion 252 and a rotating latch portion 253 coupled to each other. In the present invention, a label rotary latch mechanism is installed between the label connecting portion 24 and the label connector 25 , which is the similar to the rotating latch mechanism installed between the base 11 and the label base 21 . In other words, the assembly, operating method or spatial position of the label rotary latch mechanism and the rotating latch mechanism are the same, and thus will not be repeated. After the label connector 25 is coupled to the label connecting portion 24 , the label connector 25 shows a label content 254 of the trophy at the front side of the trophy, so that the content of the trophy may be changed if needed.
[0035] In FIGS. 3 and 4 , the top of the figure body 22 further includes an expansion connecting portion 26 , and at least one expansion member 30 is coupled to the expansion connecting portion 26 , and the expansion member 30 includes an expanded base 31 and an expanded figure body 32 , and an expanded rotating latch mechanism (not labeled) is also installed between the expanded base 31 and the expansion connecting portion 26 . In this embodiment, the expanded rotating latch mechanism includes a plurality of rotating slots (not shown in the figure) formed at the expansion connecting portion 26 and a plurality of rotating latch members 311 installed at the expanded base 31 , and an expanded rotating latch mechanism installed between the expanded base 31 and the expansion connecting portion 26 is the same as the rotating latch mechanism installed between the base 11 and the label base 21 . In other words, the assembly, operating method or spatial position of the expanded rotating latch mechanism and the rotating latch mechanism are similar, and thus will not be repeated. In addition, the expanded figure body 32 of the expansion member 30 is another expanded area for showing the content of the trophy. When it is not necessary to install the expansion member 30 , the expansion member 30 acts as an end connecting member (not shown in the figure), and the expanded rotating latch mechanism installed between the end connecting member and the expansion connecting portion 26 may be reserved for connecting or replacing the expansion member 30 at a later time. In the present invention, the top of the expanded figure body 32 may have another expanded rotating latch mechanism (not shown in the figure) coupled to an expansion member, so that the content and height of the label of the trophy may be increased as required to provide a flexible assembling and manufacturing processes of the trophy.
[0036] In FIGS. 6A-6C , the bottom of the blocking portion 123 of the base 11 further includes at least one concave latch portion 125 , and the top of the disposing portion 231 includes at least one convex latch portion 233 , and the concave latch portion 125 and the convex latch portion 233 are latched with each other, and they may be in form of one or more pairs. After the rotating latch member 23 is rotated and latched to the rotating slot 12 , the convex latch portion 233 is precisely latched to the concave latch portion 125 to provide better latching and positioning effects and enhance the feel of positioning during the rotation and combining operation. In addition, the spatial positions of the concave latch portion 125 and the convex latch portion 233 may be switched. For example, the concave latch portion 125 is disposed at the top of the disposing portion 231 , and the convex latch portion 233 is disposed at the bottom of the blocking portion 123 . In addition, a label rotary latch mechanism is installed between the label connecting portion 24 and the label connector 25 , and an expanded rotating latch mechanism is installed between the expanded base 31 and the expansion connecting portion 26 . Such arrangements are applicable for latching the concave latch portion 125 with the convex latch portion 233 .
[0037] In FIG. 7 , the relative positions of the base 11 and the label base 21 are positioned and combined, wherein the base 11 has a positioning recess 13 , and the label base 21 has a positioning protrusion member 27 which can be positioned and latched to the positioning recess 13 by rotating, combining and operating the label base 21 , so as to provide better latching and positioning effects of positioning, combining and operating the base 11 with the label base 21 and enhance the positioning feel of the rotation and combining operation.
[0038] In summation of the description above, the modular trophy structure of the present invention provides a more convenient and quicker way of assembling the trophy to provide a cost-effective manufacture. In the meantime, the present invention features various way of combining the components of the trophy to provide flexible applications of the trophy to improve the applicability, practicality and value of the trophy. The present invention further has the effect of preventing the assembling and manufacture of the trophy from being dislocated or skewed, so as to improve the overall assembling quality and the display quality of the trophy. | A modular trophy structure includes a base having plural rotating slots formed at the same circumference or different circumferences of the same center; and a label object, including a label base and a figure body coupled to each other, and the label base including plural rotating latch members disposed at the same circumference or different circumferences of the same center. The rotating latch member is installed at the rotating latch slot, and the rotating latch member is operated to latch the rotating latch slot in order to combine the label base onto the base. Therefore, the trophy may be assembled more conveniently and quickly to achieve a cost-effective manufacture of the trophy, provide flexible applications and practical uses of the trophy, and improve the overall assembling quality and the display quality of the trophy. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 08/574,053, filed on Dec. 18, 1995, and now abandoned, the entire contents of which are incorporated herein by reference, which application claims the benefit of earlier filed and copending provisional application Ser. No. 60/000,143, filed on Jun. 12, 1995.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved pulping process which utilizes non-ionic and anionic surfactants as solubilizing agents to enhance white liquor penetration into wood chips and the like during chemical pulping.
2. Description of the Related Art
Chemical pulping is a process whereby wood chips, wood shavings, and/or sawdust are heated at elevated temperatures in an aqueous acid or alkaline solution, also known as white liquor or cooking liquor, in order to remove enough lignin so that the cellulose fibers can be readily separated from one another. Typically, the process is carried out by heating a mixture of wood chips and cooking liquor in a large pressure vessel called a digester. The cooking temperature is usually in the 170°-175° C. range with a corresponding cooking time of 90 minutes. The cooked chips are discharged or blown from the digester under pressure, the mechanical force of which breaks up the wood chips into individual fibers, producing the pulp. The pulp from the digester contains fiber and exhausted liquor which is black in color. The black liquor is washed from the pulp which is then screened to remove uncooked chips and other large fragments and sent on for further processing.
The efficiency of the pulping process is reflected in the degree of delignification which depends upon the extent of the penetration of the cooking liquor and the uniformity of the distribution of the liquor within the chips. Inadequate impregnation usually results in a high level of screen rejects and low pulp yield. The current trends in research and development of the pulping industry are leading towards the use of digester aids. Digester aids are materials that are added to the white liquor to increase the yield and rate. To be most efficient, these digester aids must be soluble and stable under the pulping conditions.
Anthraquinone is an example of a compound that is widely employed as a digester aid because of its relatively low cost and lack of interference with downstream paper making operations.
Unfortunately, the known digester aids are not completely satisfactory, for example, for environmental considerations in certain cases or for lack of adequate penetration and extraction of undesirable organic components in other cases. Despite numerous prior attempts, there exists no known system which enhances the efficiency of the pulp digestion to desired levels while meeting other important criteria. It is therefore a principal object of the present invention to substantially enhance the rate of digestion of wood chips and thereby reduce the pulping cycle times in the production of pulp for the paper making process.
SUMMARY OF THE INVENTION
The present invention is an improvement in the conventional chemical pulping processes by improving the efficiency by which pulp cooking liquor components penetrate the wood and enable lignin and resins to be removed from the cellulosic materials. The surprising discovery has been made that the addition of certain surfactants or combinations of certain surfactants to the white liquor in a conventional pulping process improves both the rate of penetration of white liquor into cellulose pulp and reduces the pulping cycle times. The process according to the invention comprises contacting wood chips and the like with a digester aid which is a liquid mixture comprised of white liquor containing at least one surfactant as disclosed herein below. The surfactant concentration in the liquid mixture and the contact time with the pulp chips are each adjusted so that resinous components are extracted from the pulp without substantial degradation of cellulose. After contacting at least a portion of the resulting liquid mixture-pulp combination is heated to a digestion temperature typically above about 150° C. The heating is also referred to as cooking.
The process according to the invention results in (1) acceleration of the cooking liquor penetration by reducing its surface tension, (2) the dissolution and emulsification of the resinous components that inhibit liquor penetration and diffusion, thereby significantly enhancing the penetration of the liquor into the wood chips, and (3) enhanced delignification. When the pulping solution is alkaline, the affected alkali uptake by the chips increases by several percentage points compared to the uptake obtained in the absence of a surfactants employed in the process according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
Other than in the claims and in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the term "about".
As employed herein, the term "white liquor" means an aqueous mixture of alkali metal hydroxide and a sulfide with or without further additives and in concentrations well known in the art. The Kappa number, which is directly proportional to the amount of lignin remaining in the pulp, is the volume (in millimeters) of 0.1N potassium permanganate solution consumed by one gram of moisture-free pulp under the conditions specified in TAPPI method T 236 cm-85, the method used to determine the Kappa number.
The term pulping cycle time as used herein refers to the time required to cook a sample of wood chips and the like to a given residual effective alkali.
In the process according to the invention, wood chips, wood shavings, sawdust and the like are contacted with a liquid mixture comprised of white liquor and one or more surfactants which are soluble in white liquor and which are selected from the group consisting of polymethylalkylsiloxanes of the formula II; alkoxylated silicones; co- or terpolymers of silicones and alkoxylated polyhydric alcohols; alkoxylated aryl phosphates; alkoxylated branched alkyl phosphates; alkoxylated branched and unbranched alcohols; alkyl polyglycosides and alkoxylated alkyl polyglycosides; alkali metal salts of alkyl aromatic sulfates, sulfosuccinates and a silicone; and mixtures thereof.
Nonionic surfactants which are useful in the practice of this invention are those having an HLB value of from 9 to 16 and are selected from the group consisting of polymethylalkylsiloxanes; alkoxylated silicones; co- or terpolymers of alkoxylated silicones alkoxylated branched and unbranched aliphatic alcohols; and alkyl polyglycosides. Anionic surfactants which are useful in the practice of this invention are those selected from the group consisting of a mixture of alkali metal salts of alkyl aromatic sulfates, sulfosuccinates and a silicone; alkoxylated aryl phosphates; alkoxylated branched alkyl phosphates and mixtures thereof.
Polymethylalkylsiloxanes are compounds of the formula II ##STR1## wherein A=(CH 2 ) x --O--(C 2 H 4 O) y --(C 3 H 6 O) z --R; R is an organic moiety having from 1 to 8 carbon atoms such as an alkyl and/or alkenyl group, a substituted alkyl and/or alkenyl group, an acyloxy group; m is a number from 1 to 100, n is a number from 0 to 100, x is an integer from 1 to 3, y is a number from 1 to 100 and, z is a number from 0 to 100. Preferred polymethylalkylsiloxanes are those wherein n=0, m=1, x=3, y=8, z=0 and, R is methyl; n=35, m=11, x=3, y=18, z=0 and, R is methyl; n=0, m=1, x=3, y=8, z=0 and, R is acetoxy.
In the case of silicones and copolymers of silicones and ethoxylated polyhydric alcohols, relatively high degrees of ethoxylation, e.g., about 12 to 44, preferably about 22 to 44, have been found to be preferable for the purposes of this invention. These findings are applicable to a wide range of branched alkyl and aryl phosphates, branched alcohols, alkyl polyglycosides, and like compositions and mixtures.
Alkoxylated silicones, co- and terpolymers of alkoxylated silicones are described in WO 92/05854, the entire contents of which are incorporated herein by reference.
An alkoxylated polyol is any compound having at least 2 alcohol groups wherein all or substantially all of the alcohol functionalities are etherified with a polyoxyalkylene having a degree of polymerization of at least 2 examples of which include but are not limited to ethoxylated polyols, propoxylated polyols, butoxylated polyols, and random and block ethoxylated-propoxylated polyols. Preferably, the alkoxylated polyols are ethoxylated polyols.
An ethoxylated polyol is any compound having at least 2 alcohol groups wherein all or substantially all of the alcohol functionalities are etherified with polyoxyethylene having a degree of polymerization of at least 2. Such ethoxylated polyols include, but are not limited to, ethoxylated diols such as ethylene glycol, 1,2-propylene glycol, diethylene glycol, triethylene glycol, and polyethylene glycols of various degrees of polymerization; triols such as glycerine, trimethylolethane 2-methyl-2-(hydroxymethyl)-1,3-propanediol!, trimethylolpropane 2-ethyl-2-(hydroxymethyl)-1,3-propanediol!. Polyols also include pentaerythritol (2,2-dimethylol-1,3-propanediol), diglycerol (glycerol dimer), dipentaerythritol, triglycerine, and the like.
Alkoxylated aryl phosphates are phosphate esters which are a mixture of mono-, di-, and tri-esters of phosphoric acid esterified with alkoxylated phenols or alkyl-substituted phenols. Alkoxylated branched alkyl phosphates are phosphate esters which are a mixture of mono-, di-, and tri-esters of phosphoric acid esterified with alkoxylated branched aliphatic alcohols. Preferably, the alkoxylated aryl phosphates am ethoxylated aryl phosphates. Preferably, the alkoxylated alkyl phosphates are ethoxylated alkyl phosphates.
The alkyl polyglycosides which can be used in the invention have the formula I
R.sub.1 O(R.sub.2 O).sub.b (Z).sub.a I
wherein R 1 is a monovalent organic radical having from about 6 to about 30 carbon atoms; R 2 is divalent alkylene radical having from 2 to 4 carbon atoms; Z is a saccharide residue having 5 or 6 carbon atoms; b is a number having a value from 0 to about 12; a is a number having a value from 1 to about 6. Preferred alkyl polyglycosides which can be used in the compositions according to the invention have the formula I wherein Z is a glucose residue and b is zero. Such alkyl polyglycosides are commercially available, for example, as APG®, GLUCOPON®, or PLANTAREN® surfactants from Henkel Corporation, Ambler, Pa., 19002. Examples of such surfactants include but are not limited to:
1. APG®225 Surfactant--an alkyl polyglycoside in which the alkyl group contains 8 to 10 carbon atoms and having an average degree of polymerization of 1.7.
2. APG®425 Surfactant--an alkyl polyglycoside in which the alkyl group contains 8 to 16 carbon atoms and having an average degree of polymerization of 1.6.
3. APG®625 Surfactant--an alkyl polyglycoside in which the alkyl groups contains 12 to 16 carbon atoms and having an average degree of polymerization of 1.6.
4. APG®325 Surfactant--an alkyl polyglycoside in which the alkyl groups contains 9 to 11 carbon atoms and having an average degree of polymerization of 1.6.
5. GLUCOPON®600 Surfactant--an alkyl polyglycoside in which the alkyl groups contains 12 to 16 carbon atoms and having an average degree of polymerization of 1.4.
6. PLANTAREN®2000 Surfactant--a C 8-16 alkyl polyglycoside in which the alkyl group contains 8 to 16 carbon atoms and having an average degree of polymerization of 1.4.
7. PLANTAREN®1300 Surfactant--a C 12-16 alkyl polyglycoside in which the alkyl groups contains 12 to 16 carbon atoms and having an average degree of polymerization of 1.6.
8. GLUCOPON®220 Surfactant an alkyl polyglycoside in which the alkyl group contains 8 to 10 carbon atoms and having an average degree of polymerization of 1.5.
Other examples include alkyl polyglycoside surfactant compositions which are comprised of mixtures of compounds of formula I wherein Z represents a moiety derived from a reducing saccharide containing 5 or 6 carbon atoms; a is a number having a value from 1 to about 6; b is zero; and R 1 is an alkyl radical having from 8 to 20 carbon atoms. The compositions are characterized in that they have increased surfactant properties and an HLB in the range of about 10 to about 16 and a non-Flory distribution of glycosides, which is comprised of a mixture of an alkyl monoglycoside and a mixture of alkyl polyglycosides having varying degrees of polymerization of 2 and higher in progressively decreasing amounts, in which the amount by weight of polyglycoside having a degree of polymerization of 2, or mixtures thereof with the polyglycoside having a degree of polymerization of 3, predominate in relation to the amount of monoglycoside, said composition having an average degree of polymerization of about 1.8 to about 3. Such compositions, also known as peaked alkyl polyglycosides, can be prepared by separation of the monoglycoside from the original reaction mixture of alkyl monoglycoside and alkyl polyglycosides after removal of the alcohol. This separation may be carried out by molecular distillation and normally results in the removal of about 70-95% by weight of the alkyl monoglycosides. After removal of the alkyl monoglycosides, the relative distribution of the various components, mono- and poly-glycosides, in the resulting product changes and the concentration in the product of the polyglycosides relative to the monoglycoside increases as well as the concentration of individual polyglycosides to the total, i.e. DP2 and DP3 fractions in relation to the sum of all DP fractions. Such compositions are disclosed in U.S. Pat. No. 5,266,690, the entire contents of which are incorporated herein by reference.
Other alkyl polyglycosides which can be used in the compositions according to the invention are those in which the alkyl moiety contains from 6 to 18 carbon atoms in which and the average carbon chain length of the composition is from about 9 to about 14 comprising a mixture of two or more of at least binary components of alkyl polyglycosides, wherein each binary component is present in the mixture in relation to its average carbon chain length in an amount effective to provide the surfactant composition with the average carbon chain length of about 9 to about 14 and wherein at least one, or both binary components, comprise a Flory distribution of polyglycosides derived from an acid-catalyzed reaction of an alcohol containing 6-20 carbon atoms and a suitable saccharide from which excess alcohol has been separated.
The alkoxylated branched and unbranched aliphatic alcohols which can be used in the process according to the invention are those branched and unbranched alcohols having from 3 to 22 carbon atoms, preferably 8 to 18 carbon atoms. Preferred compounds are ethoxylated branched and unbranched aliphatic alcohols having from 8 to 18 carbon atoms such as ethoxylated tridecyl alcohol. Preferred surfactants include anionic and nonionic surfactants selected from the group consisting of the following: (1) a polymethylalkylsiloxane of the formula II wherein n=0, m=1, x=3, y=8, z=0 and, R is acetoxy; (2) a polymethylalkylsiloxane of the formula II wherein n=35, m=11, x=3, y=18, z=0 and, R is methyl; (3) a polymethylalkylsiloxane of the formula II wherein n=0, m=1, x=3, y=8, z=0 and, R is methyl; (4) a phosphated aryl ethoxylate which is commercially available as AQUAQUEST®601P and TRYFAC® from Henkel Corporation; (5) an ethoxylated tridecyl alcohol which is commercially available as TRYCOL®5941 from Henkel Corporation; (6) a blend of sodium alkyl aromatic sulfonate, sodium sulfosuccinate and silicone which is commercially available as STANTEX®40 DF from Henkel Corporation.
Under certain conditions, aqueous solutions of non-ionic surfactants such as silicones or ethoxylated surfactants exhibit limited solubility as the temperatures rise. Furthermore, under caustic conditions, these surfactants may phase separate and degrade into a dark gel phase. This lessens their desirability for specific applications as digester additives, despite their very good wetting ability under normal pH and temperatures. Alkyl polyglycosides have been found to enhance the solubility of non-ionic and anionic surfactants in alkaline media. The blends exhibit good thermal stability and remain stable over a wide range of temperatures. Alkyl polyglycosides have been found to enhance the solubility of ethoxylated surfactants. The performance of selected non-ionic and anionic surfactants as wetting agents, penetrants and deresinators improves significantly when used with alkyl polyglycosides. The alkyl polyglycosides which may be used in combination with the surfactants of this invention have the formula I and are set forth above. Combinations of alkyl polyglycosides of the formula I and polymethylalkylsiloxane of the formula II are preferred. Mixture containing from about 90/10 to about 10/90 (wt/wt) and preferably from about 75/25 to about 10/75 of a polymethylalkylsiloxane of the formula II wherein n=0, m=1, x=3, y=8, z=0 and, R is methyl and an alkyl polyglycoside of the formula I wherein R 1 is an alkyl group having from 8 to 10 carbon atoms b is zero and a is 1.5 are preferred. The most preferred surfactant system is a 10/75 (wt:wt) mixture of a polymethylalkylsiloxane of the formula II wherein n=0, m=1, x=3, y=8, z=0 and, R is methyl and an alkyl polyglycoside of the formula I wherein R 1 is an alkyl group having from 8 to 10 carbon atoms b is zero and a is 1.5.
The contacting or residence time may vary with the type of pulp and will be easily determinable by those skilled in the art. The residence time for contacting is preferably between about 45 minutes and about 180 minutes. The contacting temperature may vary with the type of pulp and will be easily determinable by those skilled in the art. The contacting temperature is preferably maintained at or below about 80° C. The digestion temperature can vary but will typically be above about 150° C. and is preferably between 160°-175° C.
The concentration of surfactant in the white liquor which together form the liquid mixture for contacting the pulp can be any amount that is effective to extract the resinous components from the pulp without substantially degrading the cellulose. Typically, the amount of surfactant will range from 0.05% (w/w) to 1.0% and preferably between about 0.05% (w/w) and about 0.5% (w/w) and most preferably from 0.125% to 0.25% based on the weight of oven dry wood. Typically, the specific components extracted from the wood chips include resins, fatty acids, and lignins.
The liquid mixture which contains one or more surfactants according to the invention and the white liquor is prepared by mixing the surfactants and the white liquor using standard mixing equipment. The amount of liquid mixture that can be used to treat the pulp can vary from 70% to 85% and preferably from 75% to 80% based on the weight of oven dry wood.
The present invention is applicable to any chemical pulping process including the pulping of wood chips from oak, gum, birch, poplar and maple trees. The pulping process may be the well-known Kraft process in which wood chips are cooked in an aqueous solution containing NaOH and Na 2 S, or an acid sulfite system.
The invention is further illustrated by the following examples.
EXAMPLE 1
LIQUOR PENETRATION DETERMINATION PROCEDURE
The extent of liquor penetration into hardwood or soft wood chips is determined by means of a gravimetric test. The cooking liquor comprises 0.25% of a surfactant in white liquor on a weight basis. The liquor may be sodium hydroxide for soda pulping, or a mixture comprising sodium hydroxide and sodium sulfide for Kraft pulping. The liquor is pre-heated at 70° C. The chips are immersed in the liquor (Kraft or soda) for a period of 30 minutes. The temperature is maintained constant over the impregnation time. The chips are then filtered from the liquor and weighed. The liquor uptake is calculated as a ratio of the weight of penetrated chips over the weight of the initial chips. The black liquors generated are submitted to tests described below. The composition of a typical cooking liquor is as follows:
NaOH Concentration: 25.6g/l as Na 2 O
Na2S Concentration: 9.75g/l as Na 2 O
Sulfidity: 27.6%
Liquor/Wood Ratio: 4/1
EXAMPLE 2
ANALYSIS OF BLACK LIQUOR
The residual alkali and the amount of organic material extracted from the wood chips are determined according to standard methods. Active alkali, total alkali and effective alkali (EA) are defined in TAPPI Standard T1203 os-61 and are determined using TAPPI methods T624 cm-85 and T625 cm-85. The effective alkali of black liquors is defined as the residual effective alkali. The alkali content is determined by means of a standard titration method as set forth in the TAPPI method. Effective alkali uptake (EAU) is calculated and used as a measure of the hydroxyl uptake at the initial phase of delignification. Effective Alkali Uptake (EAU)is given by the following equation:
EAU=((EA.sub.white liquor -Residual EA.sub.black liquor)/EA.sub.white liquor)×100
The residual sodium sulfide and percent sulfidity are also determined.
EXAMPLE 3
STANDARD KRAFT PULPING PROCEDURE
A 4-liter pressure reactor is charged with white liquor and heated to 80° C. The digester aid, one or more of the surfactants disclosed herein, is added slowly. Wood chips are then added so that the liquor to wood ratio is from 4:1 to 3:1 based on weight of oven dry wood. The reactor is purged with nitrogen and then sealed. The temperature is increased at such a rate that it reaches a maximum of 170° C. in one hour. The temperature and reaction rate are recorded every 10 minutes and used to calculate the total H-factor for a particular pulping study. For example, a pulping reaction is studied so that an H-factor is identified for a given temperature reading at a given time. The reaction rates are found in table 13 on page 50 of Pulp and Paper Manufacture, Volume 5, third edition, 1989, the entire contents of which are incorporated herein by reference, which lists the H-factors for temperatures from 100° C. to 199° C. (see also Pulp Paper Mag. Can., Volume 58, pages 228-231 (1957)). The H-factor for each temperature up to 170° C. is recorded and added together. The sum of the H-factors will lie in the range of 800-1150. Pulping runs are cooked to the same H-factors and the data for the same H-factor runs are compared. The shorter the time period required to arrive at a given H-factor the more efficient the pulping reaction and the shorter the cycle time. Black liquor samples are taken from the reactor at the same time intervals that the temperatures are recorded. Lignin and total organic content of black liquors are determined by means of ultraviolet spectroscopy as set forth in Example 6. The Kappa number for each run is determined according to TAPPI method T 236 cm-85. Since the Kappa number measures the amount of lignin remaining in the pulp, the lower the Kappa number for a given cook, the more efficient the lignin removal.
EXAMPLE 4
SOLUBILITY AND CLOUD POINT MEASUREMENTS
Solubility and stability of the surfactants which were used to make up the digester aids according to the invention were assessed through determination of cloud point and phase separation. Solutions comprising a surfactant or a mixed surfactant system were heated up to 100° C., or to the point where the solutions turned turbid or phase separated. The temperature at which turbidity or phase separation is observed is the cloud point of the solution, which is the lowest temperature at which a stable and homogeneous solution can be found, at this concentration.
EXAMPLE 5
WETTING ABILITY OF THE DIGESTER AIDS
The change in enthalpy per surface area is related to the surface free energy associated with the wetting of wood chips. An exothermic heat is observed when wetting takes place. The magnitude of the change in enthalpy is an indication of the wettability of the chips, and the ability of the digester aids to enhance wetting. Surface tension measurement and critical micelle concentration for specific surfactants provide critical information on wetting and solubilizing ability of the digester aids.
EXAMPLE 6
LIGNIN AND TOTAL ORGANIC ANALYSIS
Black or white liquor is filtered using a 0.2 μm pore size filter. About 20 ml of the filtrate is diluted with distilled water to a volume of 10 ml. UV absorption spectrum is taken with respect to the initial white liquor in the region of 190 nm to 450 nm, using a Perkin-Elmer UV/visible spectrophotometer and 1 -cm quartz cuvette. For quantitative determination, the areas under the peaks are integrated using a FTIR-UV software. The UV spectrum shows three specific maxima between 250 nm and 360 nm, at 268, 290, 360 respectively. A standard is made by dissolving alkali lignin in white liquor in a wide range of concentrations. Absorption of the lignin samples is measured as described above. Two maxima are observed in the region between 250 nm-300 nm. Consequently, for the black liquors, the peaks in the 250-300 nm regions are considered specifically caused by lignin structural groups. The total organic extraction is calculated from the maxima obtained in the entire 250-450 region.
Tables 1-5 illustrate the efficacy of the digester aids according to the invention. Table 1 illustrates the effect of surfactant composition on the ability of a digester aid to remove lignin from pulp. The combination of TEGOPREN®5878 and GLUCOPON®220 (1:7.2) is most efficient in removing lignin. TEGOPREN®5878 is a polymethylalkylsiloxane. The amounts of the various extracts is proportional to the absorbency at the indicated wavelengths.
Table 2 shows the effect of the preferred digester aid, TEGOPREN®5878-GLUCOPON®220 (75:25) as a digester aid in various pulping runs using Scandinavian softwood at a dosage of digester aid equal to 0.125% based on dry wood weight and 28.5% sulfidity. All runs in Table 2 were cooked to an H-factor of 1150. Table 3 shows the Kappa number for various digester aids at two different additive dose rates. Table 4 shows the Kappa number and number of rejects for various digester aids at different active alkali amounts as percentages of dry wood weight. The following surfactant compositions pertain to each of the tables below where indicated. The control is white liquor having no digester additives. Additive A is TRYCOL®5941-GLUCOPON®220 (1:1 ). Additive B is DC®25212, trademark product of Dow Chemical. Additive C is S911, a trademark product of Wacker Silicones. Additive D is AQUAQUEST®610-GLUCOPON®220 (1:1), both trademark products of Henkel Corporation. Additive E is STANTEX®40DF a trademark product of Henkel Corporation. Additive F is TEGOPREN®5878-GLUCOPON®220 (75:25). TEGOPREN®5878 is a trademark product of Goldschmidt Chemical. Table 5 shows the efficiency of the TEGOPREN®5878-GLUCOPON®220 combination at various blend ratios. The data in Tables 1, 2 and 5 was obtained using Scandinavian softwood while the data in Tables 3 and 4 was obtained using U.S. hardwood.
TABLE 1______________________________________Pulping of Scandinavian SoftwoodLignin Removal EfficiencySurfactant 268 nm.sup.1 290 nm.sup.2 336 nm.sup.3______________________________________Control 0.872 0.795 0.398A 1.036 0.916 0.512B 1.055 0.929 0.552C 0.994 0.934 0.521D 0.990 0.885 0.495E 0.985 0.887 0.484F 1.134 0.986 0.556______________________________________ .sup.1 absorption at 268 nm .sup.2 absorption at 290 nm .sup.3 absorption at 338 nm
TABLE 2______________________________________Efficiency of TEGOPREN ® 5878 - GLUCOPON ® 220 (75:25) Kappa Number Number of RejectsActive Alkali Additive Control Additive Control______________________________________18 27 30 0.7 2.820 25.8 25.6 0.7 0.5322 -- 22.27 -- 0.53______________________________________
TABLE 3______________________________________Kappa Number for Various Digester Aidsat Two Different Additive Dose RatesSurfactant.sup.1 At 0.125% At 0.25%______________________________________A 17.9 17.2B 17.4 18.6C 18.1 17D 17.7 17.8E 17.8 17.2F 17.2 16.9______________________________________
TABLE 4__________________________________________________________________________Kappa Number and Rejects for Various Digester Aidsat Different Active AlkaliKappa Number Number of RejectsSurfactant15.5% 16.5% 17.5% 18.5% 15.5% 16.5% 17.5% 18.5%__________________________________________________________________________Control20.1 19.2 17.8 16 2.43 2 1.9 1.7E 19 17.5 17.9 16.7 3 1.8 0.9 1.8F 18.5 17.6 17.2 15.8 1.4 2.6 0.8 1.3__________________________________________________________________________
TABLE 5__________________________________________________________________________Efficiency of TEGOPREN ® 5878-GLUCOPON ® 220at Various Blend Ratios Pulping of Scandinavian Softwood Surfactant Blend Additive Active Rejects Screen Weight Dose* Alkali Kappa Level YieldSurfactant Ratio (w/w %) % Number (%) (%)__________________________________________________________________________Control 0 0 18 30 2.8 43.1TEGOPREN/ 75:25 0.125 18 27 0.7 45.8GLUCOPON220TEGOPREN/ 1:7.5 0.063 18 28.2 0.8 45.3GLUCOPON220TEGOPREN/ 1:7.2 0.063 18 25.75 0.85 46.1GLUCOPON220__________________________________________________________________________ *% based on the weight of dry wood | The efficiency by which pulp cooking liquor components penetrate the wood and enable lignin and resins to be removed from the cellulosic materials is increased by contacting wood chips and the like with a liquid mixture comprised of white liquor containing at least one surfactant selected from the group consisting of a polymethylalkylsiloxane; a co- and terpolymer of silicone and a polyhydric alcohol; an alkoxylated aryl phosphate; an alkoxylated branched alkyl phosphate; an alkoxylated branched alcohol; an alkyl polyglycoside, an alkoxylated alkyl polyglycoside; a mixture of alkali metal salts of alkyl aromatic sulfate, a sulfosuccinate and a silicone; and combinations thereof; for a residence time effective to extract resinous components without substantial degradation of cellulose and thereafter heating at least a portion of the resulting mixture and wood chips. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This non-provisional patent application claims priority and benefit of U.S. provisional patent applications having application numbers (1) 61/258,196, filed Nov. 4, 2009, entitled SECURITY SPRING FOR EARRING, and (2) 61/260,123, filed Nov. 11, 2009, entitled SECURITY SPRING FOR EARRING POST, both disclosures of which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to earring clasps or clutches, and more particularly, to an earring clasp that more securely attaches to an earring post.
BACKGROUND OF THE INVENTION
[0003] How many times have you heard someone complaining of losing his or her earring? Unfortunately, it is not uncommon for people to lose their earrings because the clasps or other devices for securing earrings are not reliable. A lost earring is not only frustrating for the owner, but it also can be very costly because earrings can be quite expensive.
[0004] Pierced earrings generally are attached to a person's earlobe by using a clasp that grasps the post of the earring. Conventional clasps are typically poorly constructed and are not difficult to remove from an earring post without actuating the release mechanism. As a result, it is not uncommon for conventional earring clasps to unintentionally fall off and allow pierced earrings to be lost.
[0005] Accordingly, there exists a strong need for an inexpensive earring clasp or clutch that securely attaches to an earring post and is very difficult to be removed unintentionally or without activating the release mechanism.
ASPECTS AND SUMMARY OF THE INVENTION
[0006] In view of the foregoing, an aspect of the present invention is to provide an improved earring clasp or clutch that securely attaches to an earring post.
[0007] Another aspect of the present invention is to provide a durable but inexpensive earring post clasp.
[0008] A further aspect of the present invention is to provide a clasp for an earring that is difficult to be unintentionally removed without activating the release mechanism.
[0009] An additional aspect of the present invention is to provide a clasp that may be used to securely attach to the post of a broach or similar type of decorative pin.
[0010] Another aspect of the present invention is to provide an earring clasp that is treated or coated with antimicrobial material.
[0011] In order to achieve the above aspects, the present invention provides a clasp for securing to the post of an earring including a torsion spring having extended ends forming a first and a second arm, said first and second arms forming an acute angle, said torsion spring forming a receptacle, a flexible member at least partially located within the receptacle, and said flexible member including an aperture for receiving an earring post. The flexible member includes a channel on at least a portion of a periphery of the flexible member for receiving the torsion spring and retaining the flexible member within the receptacle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a flexible member configured in accordance with the present invention;
[0013] FIG. 2 shows the flexible member of FIG. 1 in a receptacle of a torsion spring configured in accordance with the present invention;
[0014] FIG. 3 shows a torsion spring configured in accordance with another embodiment of the present invention;
[0015] FIG. 3 a shows a torsion spring configured in accordance with another embodiment of the present invention;
[0016] FIG. 4 shows an earring post secured within the flexible member and the torsion spring shown in FIG. 2 ;
[0017] FIG. 5 shows another embodiment of a torsion spring configured in accordance with a preferred embodiment of the present invention;
[0018] FIG. 6 shows another embodiment of a flexible member configured in accordance with a preferred embodiment of the present invention; and
[0019] FIG. 7 shows the flexible member of FIG. 6 being retained within the receptacle of the torsion spring shown in FIG. 5 in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring to the drawings, FIG. 1 shows a flexible member, donut, cushion or ring 10 configured in accordance with the present invention. The flexible member 10 is preferably constructed of a flexible, nonslip material, such as rubber or similar polymer. The flexible member 10 also can be treated or coated with antimicrobial material in order to deter the growth or inhibit the spread of germs or diseases from earring posts. The flexible member 10 further may be different colors for decorative purposes. The flexible member 10 includes an aperture or hole 16 passing all the way between a first side 12 and a second opposing side 14 of the flexible member 10 . The aperture 16 is sized to fit loosely around an earring post. Since an earring post typically has a diameter between 0.6 to 0.8 millimeters, the aperture 16 preferably has a relaxed diameter of approximately 1.0 to 1.2 millimeters. The periphery of the flexible member 10 is designed to be constricted so the resulting diameter of the aperture 16 can be decreased to less than the diameter of an earring post.
[0021] A slit 20 can be included in the flexible member 10 to enable the diameter of the aperture 16 to more easily be decreased by constricting a periphery of the flexible member 10 . A channel 18 is provided between ridges 22 and 24 on the outer periphery of the flexible member 10 . The channel 18 is configured to receive a torsion spring. The diameters of the ridges 22 , 24 are greater than the channel 18 , enabling a torsion spring to be secured within the channel 18 and between the ridges 22 , 24 .
[0022] FIG. 2 shows an earring clasp 30 configured in accordance with the present invention. The flexible member 10 of FIG. 1 is shown contained within a receptacle 33 formed by the loop of a wire 17 of the torsion spring 31 . The receptacle 33 preferably has a diameter of about four millimeters for receiving the flexible member 10 . The wire 17 is preferably a 0.9 millimeter wire gauge (ASTM-A3113 302 Stainless).
[0023] The torsion spring 31 fits into the channel 18 of the flexible member 10 formed between the ridges 22 and 24 on the outer periphery of the flexible member 10 . Ends of the torsion spring 31 are extended to form arms 32 , 34 . The arms 32 , 34 form an acute angle. Compressing or squeezing the arms 32 , 34 of the torsion spring 31 together expands or increases the diameter of the receptacle 33 , which surrounds and retains the flexible member 10 . Squeezing the arms 32 , 34 of the torsion spring 31 increases the diameter of the receptacle 33 of the torsion spring 31 , thus enabling the diameter of the flexible member 10 to increase, which enables the diameter of the aperture 16 of the flexible member 10 also to increase. When the arms 32 , 34 are released, the receptacle 33 of the torsion spring 31 contracts, constricting the periphery of the flexible member 10 and causing the diameter of the aperture 16 to decrease.
[0024] Accordingly, and in accordance with the present invention, the arms 32 , 34 of the torsion spring 31 are squeezed together to increase the diameter of the aperture 16 and enable an earring post to be easily inserted into the aperture 16 of the flexible member 10 . After the earring post is positioned within the aperture 16 at a desired location, the arms 32 , 34 of the torsion spring 31 are released, causing the torsion spring 31 to contract or constrict around the flexible member 10 , and thus causing the diameter of the aperture 16 to decrease and tightly grasp the earring post. Since the flexible member 10 is constructed of a non-slip material, such as rubber, silicon or a similar polymer, the earring post is secured within the aperture 16 of the earring clasp 30 which makes it difficult to be unintentionally removed without activating the release mechanism of the earring clasp 30 by squeezing together the arms 32 , 34 of the torsion spring 31 . In this manner an earring clasp 30 is provided for securely attaching to an earring post.
[0025] FIG. 3 illustrates a torsion spring 40 configured in accordance with another embodiment of the present invention. Similar to the torsion spring 31 , the torsion spring 40 is constructed of a flexible wire 42 preferably made from stainless steel that is looped to form a receptacle 44 for receiving a flexible member 10 . The wire 42 typically has a circular cross-sectional configuration. However, the cross-sectional configuration of the wire 31 can be a triangular or a rectangular configuration. The illustrated torsion spring 40 forms the receptacle 44 by looping the wire 31 only once. However, the receptacle 44 can be formed by looping the wire 31 multiple times, thus increasing the constricting force or strength of the torsion spring 40 .
[0026] Similar to the torsion spring 31 , the torsion spring 40 includes arms 46 , 48 that extend from ends of the wire 42 . The arms 46 , 48 form an acute angle to enable a user to more easily squeeze the arms 46 , 48 together to expand the diameter of the receptacle 44 . The arms 46 , 48 also include extensions 47 , 49 that are angled and form handles to enable a user to more easily squeeze together the arms 46 , 48 of the torsion spring 40 .
[0027] FIG. 3 a illustrates a torsion spring 45 similar to the torsion spring 40 shown in FIG. 3 . The torsion spring 45 is constructed of a flexible wire 41 forming a receptacle 43 for receiving a flexible member. A first end 51 and a second end 53 of the torsion spring 45 are formed at the opposing ends of the wire 41 . While the wire 41 of the torsion spring 45 is shown as having one loop to form the receptacle 43 , the wire 41 preferably loops multiple times to form the receptacle 43 for increased strength and constriction force. The ends 51 , 53 of the wire 41 are the locations a user grasps to squeeze the torsion spring 45 . The ends 51 , 53 can be formed from the wire 41 , or additional material can be added to form round points or even extended handles to enable a user to more easily squeeze together the ends 51 , 53 in order to expand or increase the diameter of the receptacle 43 of the torsion spring 45 .
[0028] FIG. 4 illustrates the earring clasp 30 of the present invention shown in FIG. 2 , wherein an earring post 50 having a rounded head 52 is shown being retained within the aperture 16 of the flexible member 10 . Handles 35 , 37 are included on the arms 32 , 34 . The handles 35 , 37 enable a user to more easily squeeze together the arms 32 , 34 . The handles 35 , 37 can be a coating of rubber, silicon, or similar polymer, or a wrapped material such as cloth or latex around the arms 32 , 34 . Furthermore, the handles 35 , 37 may be colored for decorative purposes.
[0029] FIG. 5 illustrates a torsion spring 60 configured in accordance with a preferred embodiment of the present invention. The torsion spring 60 is constructed of a wire 62 that is coiled or looped to form a receptacle 66 . The ends of the wire 62 of the torsion spring 60 form arms 63 , 64 . The arms 63 , 64 form an acute angle, wherein squeezing the arms 63 , 64 together cause the diameter of the receptacle 66 to increase. The receptacle 66 of the torsion spring 60 is configured to receive and retain a flexible member for holding an earring post.
[0030] FIG. 6 illustrates a flexible member 70 configured in accordance with a preferred embodiment of the present invention. The flexible member 70 includes a channel 72 having a base 74 on the outer surface periphery of the flexible member 70 . A first ridge 76 and a second ridge 78 are located at opposing sides of the channel 72 . The first and second ridges 76 , 78 also are formed on the outer surface periphery of the flexible member 70 . The first and second ridges 76 , 78 have a greater diameter than the channel 72 . The channel 72 is designed to be retained and fit within a receptacle of a torsion spring configured in accordance with the present invention.
[0031] In the illustrated embodiment, the first ridge 76 has a greater diameter than the base 74 of the channel 72 , but a smaller diameter than the ridge 78 . The top surface 75 of the first ridge 76 also is angled to enable the flexible member 70 to more easily be inserted into the receptacle of a torsion spring configured in accordance with the present invention. An aperture 71 configured for receiving an earring post passes completely through the flexible member 70 and through the first and second ridges 76 , 78 . A slit or slot 73 is included in the base 74 of the channel 72 and the first ridge 76 to enable the diameter of the aperture 71 to more easily be decreased by constricting the receptacle of a torsion spring.
[0032] FIG. 7 illustrates an earring clasp 80 configured in accordance with a preferred embodiment of the present invention. The flexible member 70 of FIG. 6 is shown being retained within the receptacle 66 of the torsion spring 60 of FIG. 5 . The sloped top surface 75 of the flexible member 70 enables the flexible member 70 to be more easily inserted into the receptacle 66 of the torsion spring 60 . Handles 82 , 84 are included on the arms 63 , 64 of the torsion spring 70 . The handles 82 , 84 can be a rubber or silicon coating on the arms 63 , 64 .
[0033] Obviously many modifications and variations of the present invention are possible 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 otherwise than as specifically described. | An clasp for securing to the post of an earring including a torsion spring having extended ends forming a first and a second arm, said first and second arms forming an acute angle, said torsion spring forming a receptacle, a flexible member at least partially located within the receptacle, and said flexible member including an aperture for receiving an earring post. The flexible member includes a channel on at least a portion of a periphery of the flexible member for receiving the torsion spring and retaining the flexible member within the receptacle. | 8 |
CLAIMS FOR PRIORITY, INCORPORATION BY REFERENCE
This application is a continuation-in-part of: (1) co-pending application Ser. No. 07/713,551, filed Jun. 7, 1991now U.S. Pat. No. 5,236,231, which is a continuation of application Ser. No. 07/427,758, filed Oct. 26, 1989, now U.S. Pat. No. 5,069,485, issued on Dec. 3, 1991; and (2) application Ser. No. 07/753,612, filed on Aug. 30, 1991, now U.S. Pat. No. 5,240,293, issued on Aug. 31, 1993 which is a continuation of application Ser. Nos. 07/713,551, filed Jun. 7, 1991, and a division of application Ser. No. 07/427,758, filed Oct. 26, 1989, now U.S. Pat. No. 5,069,485, issued on Dec. 3, 1991. All of these prior filed applications are incorporated in their entirety herein by reference.
FIELD OF THE INVENTION
This invention relates to piping systems having a brittle liner for containing harsh fluids. More specifically, the invention is concerned with sealing lined pipe connectors.
BACKGROUND OF THE INVENTION
Many piping system applications in petro-chemical and other industries involve the handling of corrosive, erosive, scaling or otherwise hard-to-handle fluids. Piping materials that can withstand these fluids can be very costly. One economic approach to handling these difficult fluids is to cover or to line the interior of low cost (non-fluid-resistant) piping with a liner which is fluid-resistant. The low-cost pipe material, such as carbon steel, provides cost-effective structural support for the fluid resistant, but less structurally adequate liner. Even when a liner is composed of fluid resistant materials, more severe applications (such as handling erosive geothermal fluids) tend to erode, chip, spall, crack, pit, and delaminate the lining material, requiring thicker liners. Thin liners may also experience coverage and tool damage problems. One type of cost effective thick liner is composed of a fluid resistant, but brittle material, such as cement.
Lined-pipe connectors typically have a primary seal at a structural interface and a secondary liner seal at a liner interface to prevent fluid from contacting non-fluid-resistant piping materials. The added liner seal must also be reliable since exposure of the non-fluid-resistant pipe material to the harsh fluids can cause piping failure even if the primary seal does not leak.
Some connectors having significantly loaded liner gaskets or seals satisfy the need for a reliable liner seal, but significantly loaded liner seals may not be practical for fragile or brittle liners. In addition, liner sealing surface preparations needed (e.g., machining) can impose other unacceptable demands on the brittle liner, resulting in damage to the brittle liner and failure at the piping joint.
One type of soft elastomeric liner seal, such as an O-ring, also typically requires a groove or retaining edge to be provided in the liner end surface. In addition to loading and anchoring the elastomeric material, the groove can provide space for seal distortion isolated from the fluid stream flow.
However, this type of seal tends to require smoother sealing surfaces and tighter tolerances (e.g., on the groove depth) when compared to gasket type seals. But reliably obtaining these finishes and tolerances for a cast cement liner sealing surfaces may not be feasible, even if machined after casing. Grooves may also concentrate stresses in a brittle liner.
Creating a reliable liner end seal is particularly challenging when a threaded connector is used. The sealing element must be compressed while at the same time be able to accept relative rotation of the joint elements (e.g., during threaded joint assembly). Since typical soft elastomeric materials used for seals, such as synthetic rubbers, also tend to adhere to sealing surfaces and have a relatively high coefficient of friction without lubrication, rotating adhering surfaces without shredding, tearing, abrading, or otherwise damaging the soft elastomeric material or brittle liner can be difficult, especially when the liner surfaces are rough and unfinished.
None of the current or alternative approaches eliminates the problems of reliable brittle liner sealing without risking damage to the liner and/or the seal. Even if the seal and liner edges are undamaged, the reliability of sealing at these lined joints may be less than desired.
SUMMARY OF THE INVENTION
A multi-piece seal has a slidable interface between pieces, and the seal is composed at least in part of a deformable and fluid resistant material at the joint interface. The slidable interface allows for rotational slippage of pieces during pipe joint assembly and disassembly, minimizing rotational stresses on the seal pieces and sealing surfaces, e.g., the ends of a brittle liner. The flexible material and geometry of the multi-piece seal allows significant seal deformation without sizable loads on the liner, resulting in a highly reliable seal at the liner joints.
At least one of the seal pieces may be attached to a liner edge for improved seal stability and reliability. One of the pieces may also be composed of glass or other relatively inert, electrically resistant and rigid material, e.g., a fluid resistant casting or end ring bonded to the brittle liner edge. The bonded end ring further limits stresses at the rotating liner edge sealing surfaces and distributes compressional loads.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a shows a cross sectional and cut away view of a lined pipe joint having a dual-element sliding seal and FIG. 1b shows a cross sectional view of the seal portion of the lined pipe joint;
FIG. 2 shows a cross sectional view of a portion of an alternative lined pipe joint similar to that portion shown in FIG. 1b with end rings;
FIG. 3 shows a cross sectional view of a portion similar to that shown in FIG. 2 of another alternative lined pipe joint;
FIG. 4 shows a cross sectional view of a portion similar to that shown in FIG. 2 of still another alternative lined pipe joint; and
FIG. 5 shows a cross sectional view of a portion similar to that shown in FIG. 2 of a three element seal in an alternative lined pipe joint.
In these Figures, it is to be understood that like reference numerals refer to like elements or features.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1a shows a cross sectional and cut away view of an embodiment of a lined pipe connector apparatus 2. An interior surface 3 of a relatively long first pipe section 4 forms an interior passageway having a centerline axis . The first pipe or duct section 4 is typically composed of a rigid structural material such as carbon steel. The first pipe section is welded at one end to a rigid pin or short first end segment 5 at a butt weldment 6. The end segment is typically composed of fluid resistant materials, such as high alloy steels. Attaching alternatives to butt weldment 6 include mating threads, adhesive, bolting, or pinned connections. The end segment 5 and pipe 4 form a pin end assembly which mates to a box end assembly.
The box end assembly includes a rigid second end segment 7, such as a ring-like pipe coupling or box end, attached to a third end segment 8 by threaded joint 9. For handling corrosive or other hard-to-handle fluids, the second end segment 7 is also composed of fluid resistant material such as high alloy steel. The third end segment 8 is attached to a second pipe section 10 by butt weldment 11 which is similar to butt weldment 6.
The long cylindrical pipe sections 4 & 10 are typically composed of conventional structural materials in order to minimize cost, and are covered by fluid resistant liners 13 & 14 to contain hard-to-handle fluids such as geothermal fluids. These pipe materials of construction are not resistant to corrosive or other attack by many hard-to-handle fluids. However, the short end segments 5 & 8 are composed of more costly structural materials resistant to these harsh fluids (such as high alloy steels) and this embodiment is not necessary recommended for cost-effective joints. The end segments 5 & 8 protect the ends of the pipe sections 4 & 10 and the brittle liners 13 & 14 protect the rest of the long carbon steel pipe or duct sections. The liner material for geothermal applications is typically a cast concrete or cement placed in the pipe as a slurry and spun around the pipe centerline into the shape of liner(s) 13 & 14. The liners once set are typically brittle, e.g., may only withstand a tensile stress of only about 100 psi, but is more typically capable of withstanding a tensile stress of 1,000 to 2,500 psi. The liner is typically capable of withstanding a compressive stress of 10,000 to 25,000 psi, i.e., ten times the tensile stress. In addition to full tensile failures, this material is also subject to microcracking, limiting compressive as well as tensile loading.
The brittle liner 13 is typically bonded or sealably attached to both the first pipe section 4 at the interior surface and the end segment 5. The first end segment 5 to first liner 13 bonding serves to attach and seal (or limit exposure of) the carbon steel pipe section 4 to the fluid flowing within any microannulus passageway of the first cylindrical liner 13. The liner-segment bond may also have to be fluid resistant unless the joint is also sealed at or near the exposed end surfaces at gap 17 (as shown in FIG. 1b). The liner end seal shown in gap 17 comprises gasket elements 15 & 16.
A second brittle liner 14 is similarly attached or bonded to both the second pipe section 10 and the third end segment 8. The bonding of second liner 14 again forms a fluid seal between the second liner 14 and the third end segment 8 preventing fluid from contacting the second pipe 10 (similar to the first end segment 5 and first liner 13 bonding).
The opposing end sealing surfaces 18 & 19 of the end segments 5 & 8 and/or liners 13 & 14 when mated or joined form a ring-like cavity or gap 17. The opposing surfaces 18 & 19 are shown generally planar and perpendicular to the centerline 14. Alternatively, the opposing surfaces 18 & 19 may form a ring-shaped cavity having a stepped, V-shaped, or other cross-sectional shape. If the point of the V-shaped (or similar) cross-section is pointed radially inward, this may help contain extrusion tendencies of a seal material during compression, but which may tend to unbond a liner from the pipe.
The brittle liners 13 & 14 are typically composed of an inert cementitious material, such as portland cement blended with silica flour or polymer concrete. The sealing surfaces 18 & 19 of a cementitious liner may be irregular or rough which can be difficult to seal with a deformable seal. Concrete surfaces may also be porous, making sealing with a deformable seal still more difficult. The radial thickness "D" of the cementitious liner (as shown in FIG. 5) is at least 0.32 cm (1/8 inch) in this embodiment as per American Petroleum Institute "Recommended Practice for Application of Cement Lining to Steel Tubular, Good, Handling, Installation and Joining" which is herein incorporated by reference. However, radial thickness "D" is a function of pipe size, liner materials, fluid properties, etc., and other thicknesses may be appropriate for different embodiments and applications.
A liner seal at the liner ends of a threaded, brittle-lined pipe joint to perform more effectively should form a fluid barrier, be fluid-resistant, be slidable as the threaded joint is rotated during assembly, be easily deformable to limit sealing loads on the brittle or fragile liners 13 & 14, and be somewhat resilient to accommodate fluctuations in gap width. A "fluid-resistant" material is defined, for the purposes of this invention, as a material able to withstand the corrosive, erosive or other deleterious effects of the flowing fluids within the pipe sections. Without the fluid-resistant liner seal, harsh fluids would attack the structural non-fluid-resistant material of the piping (e.g., if the liner unbonds).
But the cementitious portion of sealing surfaces 18 and 19 can have a rough surface finish as cast, making it a difficult-to-seal surface. Although the surface finish can be improved, e.g, by controlling aggregate size, sealing these rough and irregular surfaces presents problems. These rough surfaces can be sealed by the expanded graphite gaskets or other highly compressible materials, but if greater reliability is desired, the surfaces can be machined or otherwise trued and smoothed.
The multi-element liner end seal or gasket (composed of dual seal elements 15 & 16) is shown compressed by the liner and segment end surfaces 18 & 19 in FIG. 1a and contacting, but uncompressed by these surfaces in FIG. 1b. The end surfaces 18 and 19 are separated by a distance "A" when the liner seal is fully compressed and by distance "B" when just contacting the liner seal, but not compressing it. Compression is achieved by squeezing and rotating the threaded pipe sections 4 & 10 together. The space between the liner seal elements 15 & 16 is shown in FIG. 1b for clarity in identifying each seal element, but the liner seal elements would be contacting each other as well as the liner end surfaces 18 & 19 when the end surfaces are separated by distance "A" or "B."
The multi-element gasket (seal elements 15 & 16) is mostly composed of an expanded graphite material, but may also be composed of other deformable materials having at least partial resiliency after deformation and a minimum lubricity. The sealing loads developed by the deformed material are limited by compressing both seal elements only over a compressing distance equal to distance "C" which is equal to contact distance "B" (when seal is initially contacted) less final gap or distance after compression "A." The preferred compressing distance "C" is no more than about 35 to 40 percent of contacting distance (or original total thickness) "B" for flexible graphite gaskets in thick cement-type liners, but the compressing distance "C" can be a larger range for other applications. More typically, compression is at least about 20 percent. Compressing the expanded graphite gaskets 35 to 40 percent can typically result in axial strains of as much as 3000×10 -6 inch/inch, but may be a little as 200×10 -6 inch/inch. For a reduced (expanded graphite) compression, the strains are typically reduced from this range.
Each of the deformable liner seal elements 15 and 16 may be bonded or attached to the end surfaces 18 and 19, but bonding is not required in the preferred embodiment. Even if not bonded, the rough and porous surface of the liner ends 18 and 19 tends to mechanically adhere the deformable seal elements 15 and 16 to these contacting surfaces. The seal to liner adherence prevents or limits differential movement at these contacting surfaces when the pipe sections are threadably rotated to accomplish the desired compression and joint makeup.
Differential movement or sliding during threaded rotation is achieved at the seal element 15 to seal element 16 interface. Sliding capacity at this slidable interface can be enhanced by the application of lubricants, but the lubricity of the preferred graphite materials of construction allows compression and sliding without added lubrication. These materials of construction avoid the need for a fluid resistant lubricant and the risk of unwanted lubricant contamination of other fluid components.
The preferred liner seal material of construction is a flexible or expanded graphite, such as Calgraph®, B grade, supplied by Pacific Mechanical, Inc. located in Santa Fe Springs, Calif., and Graphoil, supplied by Union Carbide Inc. Alternative materials of construction which would typically not require lubricant at the seal-to-seal sliding interface include: Teflon (for less elevated temperature applications), reinforced Teflon or Teflon coated elastomers, and nylon (for less hard-to-handle fluids). Other elastomer seal materials may a lubricant. Typical properties of the flexible graphite material are listed in Table 1.
TABLE 1______________________________________TYPICAL PROPERTIES-EXPANDED/FLEXIBLE GRAPHITEPROPERTY UNITS VALUE______________________________________Resistivity OHM-IN. parallel/ 0.004/0.025 perpendicular to surfaceBulk Density lb/FT.sup.3 (gm/cc) 70.0 (1.1)Thermal Conductivity BTU-in/hr-ft.sup.2 -°F. 1532Thermal Expansion 10.sup.-6 /°F. 2.8-4.4Hardness Shore Scleroscope 30-40Tensile Strength psi 700 minPermeability of Air cm.sup.2 gm <0.00001Emissivity at 932° F. -- 0.4Sublimation Temp. °F. 6600Temp. Limit (in air) °F. 1000Coef. of Friction -- 0.05(against steel)______________________________________
More reliable sealing can be obtained from these graphite gaskets even where the tolerances on dimension "C" are large, the liner/pipe segment end surfaces are misaligned, the liner partially unbonded, and the liner end surface is very rough, e.g., conventionally as cast. This improved sealing reliability is primarily due to the large compressibility of the flexible graphite seal elements. As both of the seal elements are compressed, the large compressibility allows the graphite material to fill in rough liner end surfaces and unbonded spaces. The large compressibility also minimizes the adverse effects of a smaller area of sealing due to misalignment or reduced compression distance caused by dimensional tolerance variations. Although the compressibility of the deformable seal elements is theoretically unlimited, a minimum compressibility of at least about 20% while retaining a resilience or recovery of at least about 10% and a creep relaxation of no more than 5% is preferred. A greater compressibility (while limiting stress) of at least about 30% is more preferred. Still greater compressibility of at least about 40 to 60% is still more preferable, but may be difficult to obtain. More typically, a compression ranging from about 25 to 35 percent is expected for the preferred expanded graphite materials of construction.
The graphite's low permeability also assists in obtaining a reliable seal. Although the permeability of the deformable seal elements is theoretically unlimited, a minimum permeability of no more than that of the liner is acceptable (typically less than about 0.00001) is preferred, a permeability of no more than about 10 percent of the liner more preferred, and a permeability of no more than about 1 percent of the liner still more preferred.
Another important property of the liner end seal material (with or without lubricant) is its lubricity and/or coefficient of friction against itself. Although the seal material coefficient of friction against itself is preferably no more than 0.3 without lubricant, more preferably limited to no more than 0.1 without lubricant, and still more preferably no more than about 0.05 without added lubricant, this property can typically range from as little as about 0.01 (with lubricant) to as much as about 0.7 (without lubricant). For seal elements having still higher static coefficient of friction (against itself) and or having a coefficient of friction against itself greater than against the sealing surface, the contacting (sealing) surfaces of the liner/piping may be roughened to increase friction at these contacting surfaces or even bonded, assuring slippage occurs between the seal elements 15 & 16.
In the preferred embodiment for geothermal applications, the liner and end seal must also be able to withstand scaling fluid temperatures of up to about 600° F. (316° C.), pressures of up to about 1200 psig (82.7 atmospheres), salinities of up to about 30 percent, fluid pH as low as about 2 and as high as about 8, and a fluid velocity up to about 200 feet per second or fps (60.96 meters per second). The liner seal must withstand these conditions without significant loss of resiliency, shrinkage, swelling, or long term degradation.
Each of the gaskets 37 & 38 may be formed using laminated ring construction. The plurality of layers may include an alloyed metallic layer imbedded in layers of flexible graphite or other deformable materials. The metallic layer provides a ring-like reinforcement of the graphite or other layers. The layered construction may provide multiple slidable interfaces if the layers are not bonded to each other.
In the embodiment shown in FIGS. 1a and 1b, the gaskets 15 and 16 also form a redundant fluid seal between the opposing surfaces of the metallic end segments as well as the liners. The squeezing by the metal segments also anchors the gaskets. This redundancy of sealing and anchoring further assures the reliability of sealing in a harsh environment. However, compression may be limited by the induced loads placed upon the brittle liner.
FIG. 2 shows a cross sectional view of an interface portion of an alternative embodiment connector apparatus similar to the view shown in FIG. 1b. The lined pin end 20 and lined box end 21 pipe sections are a similar configuration to the lined high alloy end segments shown in FIG. 1, but are composed of non-fluid resistant structural materials, such as steel or other conventional materials, requiring a primary seal at the mating liner end surfaces. A primary seal, as used herein, is a fluid barrier that is expected to function in the absence of other seals, whereas a secondary seal may not function in the absence of other seals, e.g., a joint gap filled with a putty (secondary seal) may be blown out upon loss of a primary seal at the joint. The interior or passageway 24 of the pin end 20 and box end 21 pipe sections have liners 22 and 23 which do not extend to entirely cover the interior passageway 24, i.e., the liner ends are setback to allow placement of end rings 35 and 36. Although the passageway 24 is shown extending in both pipe sections, the passageway may not be present in one or both portions of the joint, e.g, an end cap. If end rings 35 and 36 are not present, the setback of the liner end surfaces 25 & 26 prevents excessive (rotation and) compression of the dual element seal (15 & 16) between the liner end surfaces. However, the use of glass or other end rings 35 and 36 provides more suitable end surfaces to seal against and allows full compression if required. Thus, even if the opposing pipe end surfaces 27 & 28 are abutting, the set back of the liner end surfaces 25 & 26 allows placement of end rings and/or limits the liner end compression of the dual seal elements.
The dual element gasket 15 & 16 also anchors and forms a redundant seal at the metallic pin and box end surfaces 27 & 28, similar to that shown in FIG. 1a. Because the metal pipe can typically withstand much larger stresses and is no longer limited by the loads on the brittle liner, compression may be increased at the metallic interface, anchoring the seal and producing a more reliable liner seal.
FIG. 3 shows a cross sectional view of an interface portion of the preferred embodiment connector apparatus similar to the view shown in FIG. 2. The pin end 31 and box end 32 metal pipe sections are threadably attached similar to the pipe sections 20 & 21 shown in FIG. 2, but the pipe does not directly compress the gaskets 29 & 30. The interior pin end 31 and box end 32 pipe sections have liners 22a and 23a which do not extend to entirely cover the interior 24a of the pipe sections, similar to that shown in FIG. 2. The liner recess or setback from nose and shoulder of the pin and box ends respectively, again prevents excessive (rotational) compression of the dual element seal (29 & 30) even when the opposing pipe end surfaces 27a & 28a abut. Although the multi-element gasket seal is no longer anchored by pipe end compression, abutting pipes result in more repeatable and consistent compression. The dual seal elements 29 and 30 may also be attached to the liner end surfaces 25a & 26a, if anchoring is required. Alternatively, the joint could shoulder the seal at a different point and still trap the ring seals or gaskets between the nose and shoulder ends.
FIG. 4 shows a cross sectional view of an interface portion of a four element seal in another alternative embodiment connector apparatus. The pin end 31 and box end 32 pipe sections are threadably attached similar to the pipe sections shown in FIG. 3. The interfacing portions of the pin end 31 and box end 32 pipe sections have liners 22b and 23b which do not extend to entirely cover the interior 24a of the pipe sections. The liner end surfaces 25b & 26b are set back further than shown in FIG. 3 which allows end foils or end rings 35 & 36 to be bonded to the liner end surfaces 25b & 26b. A similar compression as a percent of the dual gaskets 33 & 34 can be achieved by the end rings 35 & 36, but a greater compression without liner damage may be possible because of the more even load distribution achieved by the end rings.
The end rings 35 & 36 also provide a finished or an otherwise smoother sealing surfaces contacting the dual sealing elements 33 & 34 when compared to the rough concrete liner end surfaces 25b & 26b. The end rings 35 & 36 are typically composed of a rigid, fluid-resistant material, such as glass polished high alloy steel if galvanic corrosion is not anticipated. Other processes to obtain the finished sealing surfaces on the end rings 35 & 36 include machining, rolling, and stamping.
The set back distance of the end rings 35 & 36 from the pipe end surfaces is selected to again prevent excessive compression of the dual element graphite seal (33 & 34). Thus, even when the opposing pipe end surfaces 27a & 28a abut, the set back of the liner end surfaces 25b & 26b and thin end rings 35 & 36 results in a predictable maximum % compression of the dual seal elements 33 & 34 having a given total thickness.
FIG. 5 shows a cross sectional view of an interface portion of a three element sealing element comprising dual deformable gaskets 37 & 38 and a landing ring 39. The deformable gaskets 37 & 38 (and gasket end ring in an alternative embodiment) are preferably contacting the landing ring 39, but these elements may also be spaced apart. The pin end 31a and box end 32a pipe sections are threadably attached similar to the pipe sections shown in FIG. 3. The internal surfaces 24a of the pin end 31a and box end 32a pipe sections have covering liners 22c and 23c which protrude or extend beyond the pipe section as well as entirely covering the interior passageway. For the thicker landing ring shown, the protrusion of the liner end surfaces 25c & 26c allows the pipe sections to contact and seat on the landing ring 39 while simultaneously compressing the dual deformable gasket elements 37 & 38. Other embodiments, e.g., using a landing ring thinner than the total thickness of the gaskets 37 & 38, may preferably have the liner end surfaces 25 & 26 set back while the pipe ends contact the thinner landing ring to achieve similar compression of the dual gaskets 37 & 38 without the risk of damage to a protruding brittle liner.
The landing ring 39 prevents excessive (rotational) compression of the dual element seal (37 & 38). When the pipe end surfaces abut the landing ring 39, the liner end surfaces 25c & 26c are compressed a known amount for a specific total thickness of the dual gaskets 37 & 38.
Several slidable interfaces may be present in this embodiment. When the pipe sections are rotated with respect to each other, the gasket-to-gasket and gasket-to-landing ring interfaces (if contacting) may slide against each other in the absence of the gasket-to-sealing surface sliding. Although landing ring sliding typically requires the landing ring to gasket contacting surface to be smooth, such as a glass or polished surface, the landing ring surface may be rougher if the liner end surfaces (or other landing ring surfaces) are unfinished.
A redundant seal may again be formed by the landing ring seal assembly shown. Although the ring joint lands provide for torque requirements, the landing ring 39 and dual gasket 37 and 38 may also redundantly seal at this interface. Thus, reliability of the seal is enhanced.
The nominal radial width "A" of the dual gaskets 37 & 38 (and liner in the embodiment shown in FIG. 5) is approximately 3/4 inch (1.905 cm), but may typically range from about 1/32 to 11/4 inches (0.07938 to 3.175 cm). Although substantially equal gasket thicknesses are shown, the nominal axial thickness of each of the dual gaskets may range from about 1/32 to 3/4 inches (0.07938 to 0.3175 cm) resulting in a total axial thickness (prior to compression) of from about 1/16 to 1/4 inches (0.1588 to 0.635 cm). The nominal landing ring radial width is approximately 1/8 inch (0.3175 cm). The nominal axial thickness of the landing ring is approximately 0.18 inches (0.4572 cm) for a 1/4 inch total thickness gasket (1/8 inch each) at 30 percent compression.
The invention satisfies the need to provide sealed connectors which can structurally and environmentally withstand severe environments at minimal cost. The process of using these sealed connectors is to place a multi-element, internally sliding seal proximate to a liner end or other sealing surface and compress the seal using a mating joint element. When the mating joint element is rotated and compressed, the internal sliding seal design precludes sliding (and sliding damage) at the seal to liner end interfaces, e.g., when joint ends are threadably joined. In one embodiment, the seal elements are also compressed by opposing structural pipe surfaces to form a redundant pipe and liner seal which anchors the seal. The use of low cost threaded piping with a brittle liner and deformable seals, such as dual gaskets, achieves a reliable and low cost sealed joint. The joint, end rings, and seals may also be reusable.
An alternative process first places an expanded graphite gasket-like element at a cementitious (or other rough) liner end surface and compresses the gasket-like element, followed by removal of the compression load and replacement of the gasket-like element with a different seal. The use of a graphite gasket having a slidable interface for the gasket-like element avoids liner and other damage caused by compression and rotation.
The process step of compressing the expanded graphite (gasket-like element) by the rough liner end surface drives graphite into the crevices and recesses of the cementitious surface (i.e., leaves a graphite residue) which is not removed when the gasket-like element is removed. The residue in the recesses upgrades or improves the surface finish (e.g., reduces surface roughness) so that a conventional or other deformable seal which previously would not reliably seal the joint can now be compressed by these surfaces and achieve a reliable seal. If the graphite gasket-like element is compressed by a liner and carbon steel surface, similar to that shown in FIG. 2, the graphite may also tend to coat and protect the carbon steel surfaces against the corrosive effects of the hard-to-handle fluid. The graphite gasket-like element can also be reused for impregnating other liner or pipe sealing surfaces.
The impregnation not only provides a less rough surface, but provides an improved slipping surface, i.e., having a lower coefficient of friction. The impregnated liner end surface joints can be threadably rotated without damaging a new seal or brittle liner. The new seal may be a single gasket or other conventional seal.
Another advantage of some embodiments of the invention process and apparatus is avoiding the potential for galvanic corrosion. The high alloy end segments shown in FIGS. 1a & 1b may encourage galvanic corrosion at a weldment or other attachment to the carbon steel pipes. The embodiments which seal in the absence of the high alloy end segments or other dissimilar metals avoid the potential for galvanic corrosion.
The invention is further described by the following sample test data summarized in Table 2.
TABLE 2______________________________________SEAL COMPRESSION TEST DATASEAL FINALARRANGEMENT LUBE RECESS CONDITION______________________________________2 × 1/32 Graphite None Flush Crimpled at 60%2 × 1/16 Graphite None Flush Crimpled at 47%2 × 1/8 Graphite None Flush Opened at 50%2 × 1/32 Graphite None Flush Rippled at 100%2 × 1/32 Graphite None Flush Ripped at 100%2 × 1/16 Graphite None Flush Good2 × 1/16 Graphite None Flush Good1/4" C-seal Red 0.160" extruded at 20%3/16" C-seal Red 0.160" left groove3/16" & 2 × 1/32 None 0.160" Springs crushedgraphite3/16" C-seal Red 0.160" Springs crushed & cement failed3/16" C-seal Red 0.160" --Silicon None Flush --Silicon None Flush 0.020 gap______________________________________
The data in Table 2 are illustrative of specific modes/tests of the compression boundaries of some embodiments of the invention and are not intended as limiting the scope of the invention as defined by the appended claims. The sample data were derived from testing of an instrumented 95/8 inch nominal diameter, lined-pipe, threaded joint. The instrumentation recorded temperature, pressure, loads, strain, leakage, and a video record of gasket element motion during assembly and compression of some types of connectors and seal designs.
While the preferred embodiment of the invention has been shown and described, and some alternative embodiments also shown and/or described, changes and modifications may be made thereto without departing from the invention. Accordingly, it is intended to embrace within the invention all such changes, modifications and alternative embodiments as fall within the spirit and scope of the appended claims. | A multi-piece, pipe joint seal has a slidable interface between seal pieces. The slidable interface allows for slippage between pieces during pipe joint assembly and disassembly, minimizing rotational and other stresses on the seal pieces and pipe sealing surfaces which may damage or endanger the deformable seal. The slidable interface seal is especially useful for joining brittle-lined pipe sections handling harsh fluids. | 8 |
RELATED APPLICATION
[0001] This application claims priority to, and the benefit of, co-pending U.S. Provisional Application No. 60/637,879, filed on Dec. 20, 2004, U.S. Provisional Application No. 60/637,789, filed on Dec. 20, 2004 and U.S. Provisional Application No. 60/580,930, filed on Jun. 18, 2004, for all subject matter common to these applications. The disclosures of the above-mentioned applications are hereby incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to coating of tubes, and more particularly to a system and method for coating and/or renovating deteriorated or pitted tubes to extend tube life and enhance performance.
BACKGROUND OF THE INVENTION
[0003] Metal tubes have many different applications across a broad spectrum of industrial uses. One example use of metal tubes is in heat exchanger configurations. Fluids or gases running through and over the tubes in the heat exchanger provide heating or cooling as desired. One such heat exchanger application is in the form of a condenser. A condenser is generally utilized to cool steam as it passes over the heat exchanger tubes, which have cooling water passing therethrough. Corrosion, deterioration, erosion, pitting, and fouling of condenser tubes can play a major role in the effectiveness of the heat exchanger apparatus. In addition, maintenance costs, water, chemistry, replacement costs, and down time for repair, are other issues that relate to the performance of the tubes in the condenser or heat exchanger.
[0004] The purpose of the tubes in heat exchanger configuration is to provide a barrier between the cooling media (in the form of water, most often) and the heated fluid, and to facilitate heat transfer. Over the course of time, the inner surfaces of the tubes can pit or erode, and eventually may begin to leak and cease to be an effective barrier.
[0005] In an effort to prevent or delay the formation of pits or erosion within the tubes, epoxy coatings and other rebuilding compounds have been used. In particular, coatings have been used to protect tube interiors of copper based alloys at the inlet end where water turbulence in conjunction with entrained solids can cause accelerated erosion damage. Coatings extending three inches to twenty four inches into the tube have been successful in preventing degradation in this area.
[0006] In addition, more recent approaches have involved coating the entire length of the tubes. Since coatings often significantly reduce fouling and corrosion of the inner surfaces of the tubes, long term performance of coated tubes can ultimately be better than uncoated tubes. One potential side effect associated with the use of coatings is the extent to which heat transfer varies with different characteristics relating to the coatings. Various factors will affect how a coating affects heat transfer, such as but not limited to thermal conductivity of the coating, interface effects between coating and tube, interface effects between multiple coatings, laminar flow effects, fouling effects and applied thickness. The thermal conductivity of the coating is a factor of the resin and filler blend in addition to how well integrated the resin and filler blend are to the other. Interface effects are a function of coating wetability and application parameters, such as temperature, humidity, dust control, and number of coats. In addition, the applied thickness of the coating varies with the number of coats. More specifically, conventionally two coats have been applied to the interior portions of the tubes, however, one coat is preferable because of the reduced thickness and reduced material costs. A full length tube coating currently is typically applied using a spraying process resulting in a coating thickness on the order of 2 mils to 5 mils. Such a thickness can penalize heat transfer capabilities, reducing them in the range of 15%-38% before fouling factors are considered.
[0007] Once tubes are placed into service in a heat exchanger they develop protective oxide layers and begin to foul. If the fouling rate is rapid, then tube performance can degrade quickly. Depending on the design cleanliness assumptions and available capacity of tubes, such degradation of performance is tolerable to a certain extent until such time as the heat exchanger must be cleaned or the tubes ultimately replaced. Coatings can prevent formation of oxides and also reduce the rate at which fouling occurs.
[0008] A significant concern relating to the degradation of heat transfer characteristics and overall performance of heat transfer tubes relates to the effect of pin holes or pitting due to corrosion of the inner surface of the tube. Currently, common materials utilized for tubes include copper alloys, stainless steel alloys, and titanium alloys, and carbon steel. These tubes work by forming passive films in their intended service. When the passive film breaks down, corrosion occurs. Coatings placed on the inner surface of the tubes can obviate the need for a passivation layer to form.
SUMMARY OF THE INVENTION
[0009] There is a need for an improved system and method relating to the application of a coating to the inner surface of tubes to both provide a protective coating and repair or renovate corroded or pitted inner tube surfaces. The present invention is directed toward further solutions to address this need.
[0010] In accordance with one aspect of the present invention, a pig device for use in the application of a coating material to a tube includes a main body portion. A coating applicator is disposed at a first end of the main body portion. An end flange is disposed at a second end of the main body portion. The coating applicator is configured to distribute the coating material onto the tube, and the end flange is configured to wipe excess coating material from the tube, to result in a coating formed on an inner surface of the tube.
[0011] In accordance with aspects of the present invention, the pig device is configured to be blown through the tube using a propellant. The coating applicator and the end flange are configured to apply an epoxy-based coating. The surface of the pig device is modified to control application of the coating material.
[0012] In accordance with one embodiment of the present invention, a method of coating an inner surface of a tube includes providing coating material in the tube. A pig device is provided in the tube, positioned to push the coating material through the tube. The pig device is propelled through the tube to apply the coating material to form a coating.
[0013] In accordance with one embodiment of the present invention, a system, method and device for coating an inner surface of a tube is provided wherein a pig device is motivated along the length of the tube using a propulsion mechanism. This propulsion mechanism may take numerous forms, including a pressure differential or a mechanical means. Following propulsion of this pig device through the tube a coating is thereby provided along the inner surface of the tube. This applied coating may be of uniform thickness and may have a minimal effect on the heat transfer characteristics of the tube. This applied coating may fill eroded elements in the tube, renovate regions of the tube which have deteriorated, span and bridge cracks in the tube or may serve to provide a uniform coating along the interior surfaces of the tube wherein the tube material is encapsulated.
[0014] In accordance with one embodiment of the present invention, the pig device utilized in applying a coating may be configured such that the coating applicator is manufactured from a compressible material or in the alternative the coating applicator may be manufactured from an incompressible material. The compressible coating applicator, in one embodiment, may be sized such that upon application of a propulsion mechanism to the pig device the coating applicator compresses. In another embodiment, the incompressible coating applicator may further contain a plurality of ridges and ribs associated with the coating applicator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The aforementioned features and advantages, and other features and aspects of the present invention, will become better understood with regard to the following description and accompanying drawings, wherein:
[0016] FIG. 1A is a perspective view of a pig device, according to one aspect of the present invention;
[0017] FIG. 1B is a perspective view of a pig device, according to an alternate aspect of the present invention;
[0018] FIG. 2 is an alternate perspective view of the pig device, according to one aspect of the present invention;
[0019] FIG. 3 is a perspective view of an end cap of the pig device, according to one aspect of the present invention;
[0020] FIG. 4A is a diagrammatic illustration of the pig device in use in a tube, according to one aspect of the present invention;
[0021] FIG. 4B is a diagrammatic illustration of the pig device in use in a tube, according to an alternate aspect of the present invention;
[0022] FIGS. 5A, 5B , 5 C, 5 D, and 5 E are diagrammatic illustrations of the pig device in use, according to one aspect of the present invention;
[0023] FIG. 6 is a flowchart illustrating one method of use of the pig device, according to one aspect of the present invention; and
[0024] FIGS. 7A, 7B , 7 C, 7 D, 7 E and 7 F are perspective illustrations of alternative pig device embodiments, according to aspects of the present invention.
DETAILED DESCRIPTION
[0025] An illustrative embodiment of the present invention relates to a system and method for coating and/or renovating the inner surface of a pipe or tube, such as a heat exchanger tube. The system and method involve providing a pig device configured to be inserted into the tube with a selected quantity of coating material. The pig device is pushed through the tube with compressed air. While the pig device travels along the inner surface of the tube, the pig device transports the coating material and applies the coating material to the inner surface of the tube to form a coating. If there are pits or other deterioration or erosion elements on the inner surface of the tube, the coating fills in such elements to repair or renovate the tube surface. The pig device can be used in on-site applications where the heat exchanger tubes are in their installed configuration. Alternatively, the tubes can be coated using the same device and process in a manufacturing setting where the tubes are being fabricated for eventual installation into a heat exchanger, or for some other application requiring a coated tube.
[0026] FIGS. 1 through 7 F, wherein like parts are designated by like reference numerals throughout, illustrate an example embodiment of a system and method for applying coatings and/or repairing inner surfaces of tubes according to the present invention. Although the present invention will be described with reference to the example embodiments illustrated in the figures, it should be understood that many alternative forms can embody the present invention. One of ordinary skill in the art will additionally appreciate different ways to alter the parameters of the embodiments disclosed, such as the size, shape, or type of elements or materials, in a manner still in keeping with the spirit and scope of the present invention.
[0027] Pigging technology falls under the genres of fluid mechanics, pipeline technology, and chemical engineering. A general definition of pigging is the propulsion through a pipe of a mobile plug pig which can execute certain activities inside the pipe or tube. Pigging can be used, for example, to clean a pipe mechanically using brushes, or to check the interior condition of the pipe or tube using a video camera. In pigging, the contents of a pipeline are pushed by a snug-fitting plug, known as the pig, with the goal of removing the contents almost completely from the pipeline. The pig is propelled through the pipe by a gas or a liquid propellant. The pig can be spherical, elongated, or composed of several parts. The pig is oversized relative to the pipe; thus, the pipe is sealed in front of and behind the pig. This enables the pig to be driven through the pipe by the gas or liquid propellant. The gas most frequently used is compressed air, and the liquid can be water or a cleaning agent or product.
[0028] It should be noted that the following description uses a heat exchanger as an example configuration for tubes that may require the functionality of the present invention. However, one of ordinary skill in the art will appreciate that heat exchanger tubes are merely one example application of tube structures having fluids flowing therethrough that may require a coating or a repair of the inner tube surface. Accordingly, the present invention is not limited to use with heat exchanger tubes, but can be used on a number of different types of tubes in a number of different configurations and having a number of different functions. The end result of the implantation of the present invention is that of a coated and/or repaired or renovated inner tube surface. As such, the invention is anticipated to be utilized in any application that may require such services.
[0029] FIG. 1A is a perspective illustration of a pig device 10 in accordance with one embodiment of the present invention. The pig device 10 is generally cylindrical in shape, as illustrated, for use in a normally configured cylindrical tube. However, one of ordinary skill in the art will appreciate that the cylindrical shape with circular cross-section can vary with the particular application, such that square, oblong, or other cross-sections can be embodied by the present invention. The present invention is thus not limited to the generally cylindrical shape.
[0030] The pig device 10 is formed of a main body portion 12 having a flanged end 14 at one end. The flanged end 14 increases the diameter dimension of the pig device 10 at the tip of the flange to perform a wiping function as later described herein. At an opposite end from the flanged end 14 the main body portion 12 supports a coating applicator 16 . The coating applicator 16 can take numerous forms as required for application of a coating, including a compressible sponge-like arrangement illustrated in FIG. 1A . In an alternate embodiment, as illustrated in FIG. 1B , the coating applicator 16 ′ can be a rigid substantially dome shaped end cap sized for insertion into a tube to be coated. The coating applicator 16 and 16 ′ can be made of a number of different materials, including but not limited to plastics, composites, polymers, rubber, and the like. Additionally, the coating applicator can have a variety of physical properties associated with the coating applicator 16 , 16 ′, including the ability to be compressed slightly for insertion into a tube in accordance with the embodiment of FIG. 1A . In an alternate embodiment, as illustrated in FIG. 1B , the coating applicator can be manufactured of a dense material which is not readily compressible. One skilled in the art will readily recognize that there exist numerous variable physical properties associated with the coating applicator 16 , 16 ′ wherein these physical properties are dictated by the tube configuration and coating application requirements. As described later herein, the coating applicator 16 , 16 ′ spreads the coating onto the inner surface of a tube as a first step in a process for applying a coating and/or repairing pits or erosion elements in the tube.
[0031] FIG. 2 is a perspective illustration of the pig device 10 of FIG. 1 , shown in a different angle perspective. As can be seen, the pig device 10 is shown as having no hollow inner cavities. However, one of ordinary skill in the art will appreciate that the primary purpose of the main body portion 12 of the pig device 10 is to provide a structure that can be pushed through a tube, not jam in the tube, and appropriately spread the coating as desired. Thus, the present invention is not limited to a solid structure, or even an enclosed structure, but can have hollow cavities in the pig device 10 to improve performance. The main body portion 12 can be made of a number of different materials, including but not limited to plastic, composite, metal, polymer materials, combinations thereof, and the like.
[0032] FIG. 3 is a perspective illustration of the coating applicator 16 ′ portion of the pig device 10 . The coating applicator 16 of the present figure is included for illustrative purposes. In the present FIG. 3 , the coating applicator 16 detailed is the same coating applicator 16 ′ depicted in FIG. 1B . On skilled in the art will readily recognize, as recited earlier, the coating applicator may take numerous forms and shapes, and may be manufactured from a variety of compatible materials.
[0033] In the example illustration, the coating applicator 16 ′ is a separate component from the main body portion 12 of the pig device 10 . However, the coating applicator 16 ′ and main body portion 12 can be a single component, as would be understood by one of ordinary skill in the art. The coating applicator 16 ′ of the present FIG. 3 has several features, one of which is a series or plurality of ribs 40 extending from a base portion of the dome to the tip portion of the dome. The ribs 40 taper at the tip of the dome to end flush with the top of the dome. However, such a taper is not necessary for the implementation of the device.
[0034] FIG. 4A is a diagrammatic illustration of the pig device 10 illustrated previously in FIG. 1B following insertion into a tube 18 or pipe. For clarity, the pig device 10 and attached coating applicator 16 ′ of FIG. 1B have been used to illustrate the orientation of the pig device 10 when located within a tube 18 or pipe. The present embodiment, however, is not intended to be limiting in any manner, as one skilled in the art will readily recognize that a variety of pig devices and associated coating applicators can be similarly situated within the inner region of a tube 18 or pipe. For example, as illustrated in FIG. 4B , the pig device 10 and associated coating applicator 16 of FIG. 1A can be readily inserted into a tube 18 to apply a coating.
[0035] The tube 18 can be made of a number of different materials, such as metal, plastic, composite, ceramic, alloy, and the like. However in the case of heat exchanger tubes, the most common material currently utilized is copper alloy, stainless steel, or titanium alloys. The tube 18 has an inner surface 20 formed by the walls of the tube 18 . In the example illustrated, the tube 18 includes erosion elements 22 (e.g., pitting, deterioration, erosion, corrosion, pin holes, and the like). The erosion elements 22 are representative of the types of defects that can occur in a heat exchanger, or other tube, over time. The erosion elements, as described above, can detract from the efficiency and effectiveness of the heat transfer by the tube 18 , and can eventually lead to leak formation and cross-contamination of fluids (from inside the heat exchanger and outside the heat exchanger). Accordingly, there is often a desire to repair such an erosion element 22 , or ultimately replace any tubes containing such erosion elements 22 , to maintain tube performance.
[0036] Returning to FIG. 3 , the rigid dome shape of the coating applicator 16 helps to evenly distribute the coating applied within the tube 18 or pipe as later described. One skilled in the art will readily recognize, however, that numerous alternative coating applicator 16 designs are applicable to the present invention, wherein these alternative coating applicators take a different shape or are manufactured from a different material as compared to the coating applicator illustrated herein.
[0037] The ribs 40 of the coating applicator provide centering and stabilizing functionality of the pig device 10 as it travels through the tube 18 . The ribs 40 are sized and dimensioned to approximate an effective diameter of the pig 10 of slightly less than the inner diameter of the tube 18 . For example, the effective diameter taken across the depth of one rib 40 and continuing along the remaining diameter of the coating applicator 16 measures approximately 0.4 mm less than an inner diameter of the tube 18 in accordance with one example embodiment of the present invention. One of ordinary skill in the art will appreciate that the exact dimension of 0.4 mm is not a limiting dimension. Rather, the sizing of the ribs 40 and the coating applicator 16 is such that the coating applicator 16 can slide through the tube 18 without being frictionally wedged inside the tube 18 . Likewise, the effective diameter of the coating applicator 16 must be large enough to provide stability and prevent the pig device 10 from tumbling within the tube 18 .
[0038] In the example embodiment, the ribs 40 are of a placement such that no two ribs diametrically oppose, or substantially diametrically oppose, each other. This feature is accomplished by positioning an odd number of ribs 40 evenly spaced around the circumference of the dome. However, there can be an even number of ribs 40 having different spacing dimensions between ribs 40 to result in the same effect of not having any two ribs diametrically opposed, or substantially diametrically opposed. If two ribs were diametrically opposed, the effective diameter of the coating applicator 16 would be significantly increased at the point of the opposed ribs 40 (the effective diameter would be the total sum of the applicator diameter plus the depth/thickness of both ribs). If two ribs 40 are diametrically opposed, such an arrangement increases the likelihood that the pig device 10 will hang up within a tube if, for example, one of the ribs passes over a raised imperfection on the inner surface of the tube that presses the diametrically opposed rib against the opposing wall of the tube, thus frictionally halting progress of the pig device 10 through the tube. Positioning the ribs 40 in a non-diametrically opposed configuration reduces the likelihood of such an occurrence.
[0039] The coating applicator 16 ′ further includes a lip 42 that extends outward from a main body portion 44 . The lip 42 extends for the circumference of the coating applicator around the base of the dome. The lip 42 is sized and dimensioned to abut the main body portion 12 of the pig device 10 , such that when the coating applicator 16 is placed within the main body portion 12 of the pig device, the surface of the main body portion 12 is flush with the lip 42 . Such a configuration creates a substantially smooth surface along the outside of the pig device 10 , thus avoiding the collection of coating material at the point of intersection between the coating applicator 16 ′ and the main body portion 12 . Furthermore, the coating applicator 16 ′ may be manufactured of a compressible material such that upon the application of a propulsion force on the pig device 10 the coating applicator 16 ′ may compress allowing the coating to pass beyond the coating applicator 16 ′.
[0040] The diameter of the main body portion 44 of the coating applicator 16 ′ is sized and dimensioned to fit snugly within the inner cavity of the main body portion 12 of the pig device 10 . To aid in the combining of the coating applicator 16 with the main body portion 12 , a flat 46 is provided on one side of the coating applicator 16 . The flat 46 enables any air trapped within the main body portion 12 of the pig device 10 as the coating applicator 16 is assembled together with the main body portion 12 to escape. As such, the coating applicator 16 ′ can more easily be mounted within the main body portion 12 of the pig device 10 .
[0041] As mentioned, the main body portion 44 of the coating applicator 16 ′ fits snugly within the main body portion 12 of the pig device. The fit can be a friction fit, holding the pieces together. Alternatively, adhesives or other mechanical bonding methods can be used, as understood by one of ordinary skill in the art, to couple the coating applicator 16 ′ to the main body portion 12 of the pig device 10 .
[0042] FIGS. 5A, 5B , and 5 C illustrate the pig device 10 in use in conjunction with the tube 18 , and also show the end result of a repair implemented by use of the present invention. In FIG. 5A , the pig device 10 using a solid coating applicator with associated ribs is shown at one end of the tube 18 . As set forth prior, the use of the solid coating applicator 16 , 16 ′ with associated ribs is solely used as an illustrative example of the present invention. One skilled in the art will readily recognize that numerous alternative coating applicator arrangements are directly applicable to the present invention. These suitable alternative coating applicator 16 , 16 ′ designs and material selection can be based upon a variety of factors including but not limited to tube inner diameter, the coating in use, the proposed coating thickness, and the length of the tube 18 to be traversed by the pig device 10 .
[0043] Prior to inserting the pig device 10 into the tube 18 , a selected quantity of coating material 24 is placed in the tube 18 . Alternatively, the coating material 24 can be placed on the end of the coating applicator 16 of the pig device 10 . The amount of coating material 24 provided depends upon a number of factors, including the length of tube 18 to be coated, the thickness of the coating, the specific configuration of the pig device 10 being utilized to spread the coating material 24 , the environment (such as humidity and temperature), the type of coating material 24 and associated coating properties (such as viscosity), and the like. Example materials forming the coating material 24 include but are not limited to epoxies, phenolics, vinal esters, poly esters, urethanes, other polymers, and other coating materials. The specific type of coating material utilized will depend largely on the purpose of the coating and the environment in which it is applied and to be maintained, as understood by one of ordinary skill in the art. For example, the coating material may contain numerous additives to improve performance of the tube or reduce further problems. A non-exhaustive list of suitable additives includes waxes, silicones, and other dry lubricants such as molybdenum disulfide.
[0044] Furthermore, to combat the growth of biological organisms along the inner surface of the tube, various algicides, biocides and fungicides can be added to the coating which kill or deter the growth of these organisms. Growth of biological organisms such as algae, fungi, bacterial and other micro organisms along the inner surface of the tube may result in fouling of the tube surface as well as the creation of obstructions within the tube. Fouling and obstructions such as this can reduce heat transfer within the tube as well as restrict or prohibit fluid flow. Furthermore, the existence of biological growth can further induce various types of corrosion along the tube wall, thereby resulting in deterioration and eventual tube failure. The introduction of algicides, biocides and fungicides into the coating material thereby serves to prevent or minimize such problems. Suitable substances for curbing biological growth include, but are not limited to ortho-phenylphenol(OPPS); isothiazolinone derivatives (such as 2-n-octyl-4-isothiaszolin-3-1 (OIT); guanides and biguanides; carbamates and dithiocarbamates; copper, sodium or zinc pyrithione; benzimidazoles; n-haloalkylthio compounds; 1-(3-chloroallyl)-3,5,7-tri-aza-1-azionia-adamantanechloride; tetrachloroisophthalonitriles; cis[1-(3-chloroallyl)-3,5,7-tri-aza-1-azonia-adamantane] chloride and 2,2-dibromo-3-nitropropionamide(DBNPA); and quaternary ammonium compounds.
[0045] Additionally, the coating materials of the present invention may be of varying viscosity. Unlike traditional coating methods, wherein the coating material is sufficiently thinned using a solvent, the coating of the present invention may be used in an un-thinned high viscosity state. The use of a thinning solvent aids in the flow of existing coating throughout the tube and helps control cure time properties. Following the coating of tube with a thinned coating, one must await the evaporation of the solvent from the coating material for the coating to cure. As heat exchanger tubing has a very low diameter to length ratio to maximize surface area for heat transfer, this confined space oftentimes makes it difficult for a solvent to migrate Further compounding this difficulty are any pits in the tube wall which may be filled with the solvented coating, whereby the likelihood that some solvent may be trapped in these pits is greatly increased.
[0046] In contrast, as the coating in the present invention is pushed through the tube, coating with higher initial viscosities can be used in an un-thinned state. For example, coatings with viscosities of 100,000 cps or greater can be readily used. In light of this, the risks associated with incomplete solvent removal are eliminated. As shown in FIG. 5B , the pig device 10 is pushed along the tube 18 in the direction of arrow A, leaving behind a coating 26 formed of a thin layer of the coating material 24 . The direction of the pig device 10 passing through the tube 18 is inconsequential to the implementation of the invention so long as the pig device 10 leads with the coating applicator 16 , 16 ′. To describe the action of the pig device 10 , the following is provided. The coating material 24 collects around the coating applicator 16 , 16 ′. This action is due to drag and frictional forces pushing the coating material 24 into the pig device 10 as it travels through the tube 18 . As the pig device 10 moves through the tube 18 , the spaces between the ribs 40 of the coating applicator 16 , in one embodiment, let an amount of the coating material 24 pass by the coating applicator 16 and collect along the main body portion 12 of the pig device 10 , between the main body 12 and the inner surface 20 of the tube 18 before the flanged end 14 . As the pig device 10 continues in the direction of arrow A, the flanged end 14 comes along and wipes the coating material 24 to form the coating 26 . In the other example embodiment, as the pig device 10 moves through the tube, the coating applicator 16 compresses thereby allowing the passage of coating material past the region defined by the coating applicator.
[0047] Even distribution of the coating material 24 is accomplished by the combination of the coating applicator 16 , 16 ′ controlling the initial amount of coating material 24 being let into the region between the main body portion 12 and the action of the flanged end 14 wiping against the inner surface 20 . As set forth prior, one skilled in the art will readily recognize that the coating applicator 16 and 16 ′ may take numerous forms and may be manufactured of a variety of materials. Regardless of material selection or coating applicator 16 forms, the coating applicator must be capable of passing a predetermined amount of the coating past the coating applicator 16 , 16 ′ and into the region defined by the main body portion 12 and the flanged end 14 .
[0048] In the instance of the existence of the erosion element 22 , the pig device 10 can be used to provide a coating patch 28 . In short, the coating material 24 is controlled by the coating applicator 16 , 16 ′ to the extent that a sufficient amount is available to fill the erosion element 22 in the form of a pit or imperfection as it exists in the tube 18 and as the pig device 10 comes across the pit or imperfection. As the pig device 10 passes over the erosion element 22 , the coating material 24 fills in any voids. Then as the flanged end 14 passes over the erosion element 22 , any excess coating material 24 is wiped away leaving sufficient material to form the coating patch 28 , filling the erosion element 22 . In areas on either side of the erosion element 22 the coating 26 is applied to the inner surface 20 .
[0049] In accordance with one example, a propulsion mechanism such as a compressed gas or liquid can be used in pushing the pig device 10 along the length of the tube 18 . In the exemplar embodiment, this propulsion mechanism is applied at the flange end 14 of the pig device 10 . As the propulsion mechanism is applied, the pig device 10 is motivated through the tube 18 to a far end. Depending on the particular tube configuration, the pig device 10 can continue, through a connector, to another tube, or alternatively exit the tube 18 . One of ordinary skill in the art will appreciate that the propulsion mechanism used in motivating the pig device 10 along the length of the tube 18 may take numerous forms. Such propulsion mechanisms include, but are not limited to, compressed gases, liquids, and the like, a pressure differential such as a vacuum, as well as a rod-like structure that can be used to manually push the pig device 10 through the tube. Applicant has found the compressed propellant to be the most effective at this time; however other propelling devices or forces can be utilized to move the pig device 10 through the tube.
[0050] In addition, the pig device 10 can be pulled through the tube 18 by a line, such as a wire, string, tape, rod, and the like, made of any number of different materials, including synthetic, non-synthetic, metal, plastic, composite, woven, non-woven, etc. Accordingly, the present invention is not limited by the particular material or structure of the device utilized to pull the pig device 10 through the tube 18 . Alternatively a negative pressure differential can be employed to pull the pig device 10 along the length of the tube 18 .
[0051] The use of the pig device 10 provides a user with added control over the dimensions of the resulting coating 26 . More specifically, the pig device 10 , by varying such portions as the coating applicator 16 , 16 ′ and the end flange 14 , can be modified to specifically result in a desired coating having a predetermined and substantially consistent thickness and distribution. For example, the coating applicator 16 , 16 ′ can be varied by material, size or shape to let selected amounts of the coating material to pass by for application. In addition, the diameter or width of the main body portion 12 can be varied to control the amount of coating material 24 being exposed to the end flange 14 . In addition, the dimensions and shape of the end flange 14 , and of the main body portion 12 , can be varied to control the distribution and amount of material being deposited on the inner surface 20 .
[0052] The configuration of the pig device 10 , with the wiping action of the end flange 14 , enables substantially improved control over the coverage and thickness of the coating 26 . In accordance with one embodiment of the present invention, coatings having a thickness on the order of less than 0.25 mils can be achieved using the pig device 10 of the present invention. This results in the ability to provide a coating that has a substantially reduced effect on heat transfer properties of the tube where the coating covers the inner surface in areas of otherwise good condition, while also repairing pits and other erosion elements 22 . Thus, the overall effect of use of the pig device 10 of the present invention on a tube in otherwise good condition is to provide a coating of thickness much smaller than past processes, with minimal heat transfer effect, but improved durability and ability to repel corrosion and other fouling or deteriorating elements. The overall effect of use of the pig device 10 of the present invention on a tube having erosion elements 22 that are detracting from tube performance is to repair and renovate the tube to restore the tube to a much improved condition, delaying the need to shut down the system and replace the tube. Additionally, the present invention can be utilized in coating a tube 18 which does not suffer from erosion elements or fouling, wherein the resulting coating is of minimal thickness. Such a uniform coating using the present invention is beneficial in industrial applications where the material the existing tube is manufactured from is incompatible with the proposed fluid for use within the existing tube. In a refrigeration setting, for example, a common copper heat exchanger that is in working order can be coated using the present invention such that a thin coating is uniformly applied to all regions of the interior of the heat exchanger tubes. This uniform coating covers all exposed copper surfaces along the interior of the tube. Following such a coating, a refrigerant that is otherwise incompatible with copper tubing can now be used, as the interior of the heat exchanger tubes no longer have any regions of exposed copper. One skilled in the art will readily recognize that this is solely an illustrative example of a use of the present invention in providing an inner surface of a tube which is compatible with the intended working fluid contained by the tube. Such an example is clearly not exhaustive of the potential used of recoated tubes.
[0053] FIGS. 5D and 5E illustrate an alternate embodiment of the pig device when used with the compressible coating applicator 16 . This illustrative example is an alternate embodiment of the present invention and is not intended to limit the scope of the present invention. In FIG. 5D , the pig device 10 is shown at one end of the tube 18 wherein a selected quantity of coating material 24 has already been placed in the tube 18 . As set forth prior, the amount of coating material 24 provided depends upon a number of factors relative to the specific application.
[0054] As shown in FIG. 5E , the pig device 10 is pushed along the tube 18 in the direction of arrow A, leaving a uniform coating 26 behind In the present embodiment, the coating material 24 collects around the coating applicator 16 . This action is due to drag and frictional forces pushing the coating material 24 into the pig device 10 as it travels through the tube 18 . As the pig device 10 moves through the tube 18 , the coating applicator 16 of the present embodiment retracts or compresses sufficiently to let an amount of the coating material 24 pass by the coating applicator 16 and collect along the main body portion 12 of the pig device 10 , between the main body 12 and the inner surface 20 of the tube 18 before the flanged end 14 . As the pig device 10 continues in the direction of arrow A, the flanged end 14 comes along and wipes the coating material 24 to form the coating 26 . The use of a compressible coating applicator 16 , as illustrated in the present embodiment, as well as the rigid coating applicator with associated ribs of FIG. 5A is not an exhaustive list of potential coating applicator embodiments. One skilled in the art will readily recognize that numerous alternative coating applicator 16 embodiments exist which are applicable to the present invention. These alternative embodiments may take numerous forms or shapes, and may be constructed from a variety of materials suitable for applying a coating.
[0055] FIG. 6 is a flowchart illustrating one example method of using the pig device 10 in accordance with one embodiment of the present invention. The coating material 24 and pig device 10 are provided in the interior portion of the tube 18 (step 100 ). The propellant is provided, blowing the pig device 10 through the tube 18 (step 102 ). As the pig device 10 travels along the tube 18 , the coating material 24 is deposited on the inner surface 20 of the tube 18 to form the coating 26 (step 104 ). If desired, the process can be repeated to provide additional layers of coating material 24 (step 106 ). It should be noted that if additional layers of coating material 24 are applied, the layers can be formed of coating material 24 that is of a different type, or the same as the initial coating material 24 . In addition, if the process is repeated, different pig devices 10 , having different properties or characteristics can be used to form coating layers having different properties. Furthermore, depending on the coating material 24 , time may be required to allow for the coating to set and cure.
[0056] FIGS. 7 A-F illustrate several example alternative embodiments of the pig device 10 in the form of pig devices 10 A- 10 F. Pig devices 10 A and 10 D have the additional aspects of longitudinal surface features 30 . Pig devices 10 B and 10 E have the additional aspects of latitudinal surface features 32 . The addition of the longitudinal surface features 30 and latitudinal surface features 32 are representative of a variety of different alternative embodiments in which the surface of the main body portion 12 is modified to have an impact on the distribution of the coating material 24 by the pig device. One of ordinary skill in the art will appreciate that different orientations and combinations of surface features, coating applicator arrangements (i.e. shape, material selection and compressibility), in addition to others not specifically described or illustrated, are possible in accordance with the present invention. Accordingly, the present invention is not limited to only the example embodiments illustrated.
[0057] In FIGS. 7C and 7F , an end flange 34 of pig device 10 C includes a plurality of valleys 36 . As the flange 34 passes over the coating material 24 , the valleys 36 in the flange 34 form ridges in the coating 26 that results on the inner surface 20 of the tube 18 . The particular pattern resulting in the coating 26 can vary, as understood by one of ordinary skill in the art, based on the shape of the flange. Such a flange 34 can be useful if multiple passes of the pig device are to be implemented. The first application of the coating material 24 can have the primary purpose of depositing the coating material 24 in a predetermined pattern of ridges, while subsequent passes of the pig device can smooth out, or otherwise modify, the resulting coating. Alternatively, the ridges or other patterns formed in the coating can form the final configuration of the coating, if such ridges or patterns are desired.
[0058] Initial implementations of the pig device 10 to provide a coating in a tube 18 have resulted in a coating of approximately 0.25 mils to 1 mil thickness that provided consistent coverage of the inner surface 20 . Heat transfer analysis of the coated tube revealed minimal effect on heat transfer properties. Tubes having one or more pits were quickly repaired by use of the pig device 10 and an epoxy coating to patch the pits with a durable patch, thus extending the work life of the tube.
[0059] Accordingly, the present invention is useful in that the implementation of the pig device to apply a coating or a coating patch enables substantially improved control over the coverage and thickness of a coating on an inner surface of a tube. Where prior methods have resulted in a minimum coating thickness of 2 mils to 5 mils, the present invention can achieve a much thinner coating, on the order of 0.25 mils to 1 mil. Thus, the resulting coating has far lesser negative effects on heat transfer properties of the tube. In addition, the pig device can be run through the tube multiple times to provide layers of coating if a more durable, or thicker coating is desired. The compressed fluid in the form of gas or liquid quickly propels the pig device through the tube, efficiently applying the coating to the inner surface.
[0060] Numerous modifications and alternative embodiments of the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. Details of the structure may vary substantially without departing from the spirit of the present invention, and exclusive use of all modifications that come within the scope of the appended claims is reserved. It is intended that the present invention be limited only to the extent required by the appended claims and the applicable rules of law. | The present invention relates to coating of tubes, and more particularly to a system and method for coating and/or renovating deteriorated or pitted tubes to extend tube life and enhance performance. Using this system and method a thin coating is applied to the interior of a tube such that the coating is uniform in thickness and covers all regions of the tube. The coating material may be selected to minimize changes in heat transfer or may be selected to provide for the change in working fluid within the tube such that the working fluid does not negatively interact with the tube material. | 1 |
FIELD OF THE INVENTION
The present invention generally relates to the management of pain associated with applying electrical cardioversion therapies. In particular, the invention relates to patient preparation in advance of application of the electrical cardioversion therapy.
BACKGROUND OF THE INVENTION
Implanted medical devices are capable of detecting and treating an arrhythmia (i.e., irregular heartbeats) in a patient. In one example, the implanted medical device includes a defibrillator that applies an electrical pulse therapy to a patient's heart upon detecting fibrillation (i.e., high, irregular heartbeat), a form of arrhythmia. Cardioverters or defibrillators discharge relatively high energy electrical shocks or pulses into or across cardiac tissue to arrest a life-threatening atrial or ventricular fibrillation upon detection by the implanted medical device. Defibrillation shocks, while highly effective at arresting the fibrillation, may occur suddenly and can cause considerable patient discomfort.
The level of discomfort that a patient experiences with defibrillation shocks is affected by many psychological factors, among which are fear and anxiety of the impending shock therapy. In one instance, the patient becomes highly distressed because the patient must rush through current activities in order to find an area for treatment, and await the application of the pre-programmed shock therapy. Patients can reduce the impact of these psychological factors by taking control over the time that the shock is applied and by physiologically preparing the body in advance of the shock delivery.
The implanted device is programmed by a physician using a programming head that is electrically connected to a programming unit similar to a personal computer. The programming of the implanted device is usually limited to the physician or a trained technician. To safeguard the patient's health, the physician programs the implanted device to automatically deliver at least one electrical shock therapy in a 24-hour period. Therefore, patient control over the application time of the shock treatment is not usually available to ambulatory patients because the patient is not authorized to program his own implanted device.
Patients can also reduce the impact of psychological factors by using any one of a number of sedatives prior to the shock delivery. Although sedation therapy may be helpful in reducing shock discomfort, sedation therapy is also impractical when the patient is traveling or when the patient needs to be alert and cannot be incapacitated by the sedative for a prolonged time period.
Accordingly, patients would be able to better manage the pain associated with electrical cardioversion therapy if they had the time to psychologically and physiologically prepare in advance of the therapy. An approach that addresses the aforementioned problems, as well as other related problems, is therefore desirable.
SUMMARY OF THE INVENTION
Various embodiments of the present invention are directed to addressing the above as well as other needs in connection with enabling a patient to control the pain associated with an electrical cardioverting therapy, by allowing the patient to control the timing of the electrical therapy. In one such embodiment, an implanted medical device is configured to automatically cause the application of an electrical therapy at least once within a selected period (e.g., 24-hour period), includes a circuit arrangement for temporarily disabling the electrical therapy application responsive to a patient activated device that is carried by the patient.
According to another embodiment of the invention, a system for temporarily disabling an electrical therapy application by an implanted medical device includes a capacitive circuit capable of charging and discharging in order to apply the electrical therapy. The implanted medical device automatically causes the capacitive circuit to charge and discharge at least once within a selected period. The system includes a patient activator device that communicates with the implanted device. A disabling circuit is also included within the implanted medical device that temporarily disables the electrical therapy application in response to the patient activator device. The system further includes an alerting arrangement that alerts the patient activator device in response to the disabling circuit. The system also includes an override circuit that overrides the temporary disabling of the electrical therapy application in response to the patient being in a relaxed mode.
According to yet another embodiment of the present invention, an implanted medical device that automatically applies an electrical therapy to a patient's heart at least once within a selected period includes a communications circuit that enables telemetric communications from the implanted medical device in response to an external patient activator device. A disabling circuit is disposed within the implanted medical device that temporarily disables the electrical therapy application. An alerting arrangement is also include that alerts the patient activator device in response to the disabling circuit. The implanted medical device further includes an override circuit that overrides the temporary disabling of the electrical therapy application in response to the patient being in a relaxed mode.
The above summary of the present invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures in the detailed description that follow more particularly exemplify these embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
FIG. 1 illustrates a block diagram of a patient-controlled system for temporarily disabling an electrical therapy provided by an implanted device according to an example embodiment of the invention; and
FIG. 2 is a flow diagram illustrating the manner of using a patient activator device to control the time that an electrical therapy is applied according to another example embodiment of the invention.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. 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.
DETAILED DESCRIPTION
The present invention is generally directed to a patient-controlled system that enables a patient to control the pain associated with an electrical cardioverting therapy by controlling the time that the electrical therapy is applied. While the present invention is not necessarily limited to such an application, the invention will be better appreciated using a discussion of example embodiments in such a specific context.
In an example embodiment, a system for delivering an electrical cardioverting therapy to a heart of a patient experiencing atrial fibrillation includes an implanted medical device that delivers the electrical cardioverting therapy within a predetermined time period upon detecting the fibrillation. The implanted medical device includes a capacitive circuit that can be charged and discharged in response to a first and a second signal, respectively. The implanted device automatically transmits the signals at least once within a predetermined time period (e.g., 24-hours) causing the capacitive circuit to charge and discharge and transmits the signals in response to the detected fibrillation. The system includes a patient activator device (PAD) that is carried by the patient and that communicates an instruction to the implanted device to temporarily disable the implanted device's control over the timing of the electrical therapy. The PAD device includes an alert feature that advises the patient that the electrical therapy is temporarily disabled.
In a related embodiment, the system includes a sleep monitor that is activated by the PAD and ensures that the patient is at least relaxed or asleep when he receives the electrical therapy. In another related embodiment, the sleep monitor is automatically activated when the implanted device detects an arrhythmia. The sleep monitor is programmable by the patient via the PAD.
FIG. 1 illustrates a block diagram of a patient-controlled system 100 for temporarily disabling an electrical therapy provided by an implanted device according to an example embodiment of the invention. A patient 102 has an implanted medical device 103 that is configured to detect an abnormal body function, such as an arrhythmia (irregular heartbeat) of a heart 105 . In this example, a detection circuit 104 detects an atrial fibrillation of the heart and transmits a warning signal via a communications module 108 to a patient activator device (PAD) 110 . PAD 110 , which can be carried, sounds an audible alarm (or emits a vibration) via an alert unit 113 , in response to the warning signal from implanted device 103 alerting patient 102 that his heart is in atrial fibrillation.
Patient 102 uses PAD 110 to instruct implanted device 103 to temporarily disable the implanted device's automatic atrial fibrillation response. In this example, the automatic response is application of an electrical cardioverting therapy or shock via a charge/discharge circuit 109 to heart 105 . Alert unit 113 advises the patient that the electrical therapy is temporarily disabled. System 100 also includes an override circuit in the form of a sleep monitor circuit 107 A (with sensor 107 B) that is activated by PAD 110 and, in conjunction with PAD 110 , ensures that the patient is at least relaxed or asleep when he receives the electrical therapy.
To induce relaxation or sleep prior to the application of the electrical therapy, patient 102 can choose to take a sedative. After taking the sedative, the patient activates sleep monitor circuit 107 A, which monitors the patient's physiological condition. If the patient decides not to take a sedative, the patient activates the sleep monitor when he is reclined or seated. Charge/discharge circuit 109 applies the electrical therapy to the patient upon detecting that the patient is in a relaxed mode or is asleep. In a related embodiment, a timing circuit is activated as part of the sleep monitor to ensure that the patient is asleep for a select period of time before applying the electrical therapy.
Heart conditions detectable by detection circuit 104 include, but are not limited to, ventricular fibrillation, tachycardia, bradycardia and eventual heart failure. In a related embodiment, a logic unit 106 in conjunction with detection circuit 104 , evaluate the severity of the detected heart condition. Logic unit 106 continues to monitor the general condition of heart 105 before triggering detection circuit 104 to warn patient 102 of a detected arrhythmia. Implanted device 103 is also programmed to automatically deliver additional electrical therapies or shocks if a preceding shock was either ineffective or an atrial tachyarrhythmia prematurely re-occurred.
In the present embodiment, PAD 110 is comprised of a communications module 114 that communicates bi-directionally with implanted device 103 via communications module 108 . PAD 110 also includes a logic unit 112 (e.g. microprocessor) that configures the electrical therapy that is applied by implanted device 103 . Unit 112 also processes warning signals from implanted device 103 and transmits them to an alert unit 113 that audibly advises patient 102 of the bi-directional communication occurring between implanted device 103 and PAD 110 . In this example, PAD 110 also includes a display 16 for reading alphanumeric messages from implanted device 103 and a keypad 118 for facilitating programming of implanted device 103 .
In another example embodiment, implanted device 103 is an implantable cardiac defibrillator (ICD) having programmable atrial tachyarrhythmia therapies with the capability to accept programmed commands from the PAD. The ICD also includes a PAD programming capability with several automatic shock and patient activated shock therapy options. A programmable option in the ICD will allow the patient to suspend therapy for a programmable duration (e.g., one-day). ICD is also capable of delivering an electrical therapy on patient-command via PAD 110 . A first signal from PAD 110 charges circuit 109 and a second signal from PAD 110 discharges circuit 109 into heart 105 . The override circuit (e.g., sleep monitor circuit) of implanted device 103 is also programmable and PAD includes additional features to assist the patient to include: a query function to determine status of atrial rhythm status; immediate delivery of an electrical therapy; an atrial defibrillation deactivation button; and a programmable delay function that can suspend therapy for up to a selected period of time (e.g., 24-48 hours).
With respect to sleep monitor 107 A, factors such as respiration rate, heart rate and patient activity are highly affected by sleep and are monitored by sleep monitor 107 A. Once activated, monitor 107 A attempts to detect a patient's state of relaxation or sleep. An example algorithm used by monitor 107 A for detecting sleep requires detecting a low activity level and a 15%-25% reduction in respiration and/or heart rate (suggested physiological measures). If monitor 107 A does not detect sleep within two hours, then the electrical therapy will be canceled. In another embodiment, the physiologic measures are combined with a timing circuit to ensure a steady state of sleep for a certain period of time before delivering the electrical therapy. This approach prohibits delivering the electrical therapy when the patient has just fallen asleep and is not yet entered REM sleep.
In a related embodiment, the patient is audibly warned (or via a vibration or light signal) by PAD 110 that the electrical therapy is to be administered shortly. In another related embodiment, PAD 110 has a programmable delay with a locking feature to ensure that the patient cannot alter the delay. The time delay can be based on the peak effect of the sedation therapy.
In a related embodiment, implanted device 103 comprises a neurological implant or nerve stimulator that includes a stimulator circuit. Logic unit 106 with detection circuit 104 and at least one sensor 107 B coordinates the detection of irregular body functions at or near the area of the implant. Upon detecting an irregularity at the implant area, PAD 110 receives telemetric communications from implanted device 103 of the irregularity and provides an alert to the patient. The stimulator circuit delivers the electrical therapy to the area upon sensing that the patient is in a relaxed mode.
In the various embodiments described herein, PAD 110 is configured to operate in harmony with implanted device 103 . For more information regarding the functionality of PAD 110 and IMD 103 , reference may be made to U.S. Pat. No. 5,987,356 to De Groot, which is assigned to the assignee of the present invention and incorporated herein by reference.
In the various embodiments described herein, modules 108 and 114 are configured to telemetrically communicate with each other using various techniques, including magnetic-field coupling, reflected impedance coupling and radio-frequency (RF) coupling. For more information regarding magnetic-field coupling, reference may be made to U.S. Pat. No. 3,311,111 to Bower and U.S. Pat. No. 3,805,796 to Terry et al., which are assigned to the assignee of the present invention and incorporated herein by reference. For more information regarding reflected-impedance coupling, reference may be made to U.S. Pat. No. 4,223,679 to Schulman et al., which is assigned to the assignee of the present invention and incorporated herein by reference. For more information regarding RF coupling, reference may be made to U.S. Pat. No. 5,843,139 to Goedeke et al., which is assigned to the assignee of the present invention and incorporated herein by reference.
FIG. 2 is a flow diagram 200 that illustrates the logic in the use of a patient activator device to control the time that an electrical therapy is applied according to another example embodiment of the invention. At step 202 , implanted device 103 detects the presence of arrhythmia, which in this case is atrial fibrillation. At step 204 , implanted device 103 determines the type of therapeutic mode: automatic atrial defibrillation or patient-activated atrial defibrillation. At step 206 of the patient activated atrial fibrillation path, implanted device 103 determines if the patient activated the therapy via a delay timer or sleep monitor 107 A. If the sleep monitor is activated at step 208 , the sleep monitor determines at step 210 if the sleep criterion for the patient is met. At step 212 , if the sleep criterion is met implanted device 103 determines whether a delay entered on PAD 110 is still engaged. If the therapy delivery time is exceeded in step 214 , then implanted device 103 determines whether the patient canceled the therapy. At step 218 , the implanted device applies the electrical therapy because the therapy was not actually canceled.
At step 206 , implanted device 103 determines that the patient did not activate a therapy, and device 103 continues to monitor for ongoing AF (atrial fibrillation) at step 220 . At step 208 , if implanted device 103 determines that the sleep monitor is not on then implanted device 103 verifies whether a delay is engaged. If no delay is detected, then at step 216 , implanted device 103 determines that the therapy was indeed canceled and continues to monitor for ongoing AF. Device 103 also continues to monitor for AF when the implanted device determines that at step 214 the therapy time delay has been exceeded. At step 210 , implanted device 103 determines that the sleep criterion is not met and continues to monitor for ongoing AF.
At step 222 on the automatic atrial defibrillation path, device 103 determines whether the patient has suspended the atrial defibrillation therapy for a fixed time period. If at step 223 , implanted device 103 determines that the suspended time is exceeded then device 103 continues to monitor for AF. At step 224 , implanted device 103 determines if there is a pre-programmed window for therapy (e.g., 4AM-6AM, daily). If there is no therapy pre-scheduled, at step 226 device 103 determines whether the sleep monitor is on. If at step 228 , device 103 determines that the sleep monitor is on and the sleep criteria is met device 103 delivers the shock therapy to heart 105 at step 230 .
Device 103 delivers a shock to the heart at step 224 if there is no therapy window and at step 226 if sleep monitor circuit 107 A is not on. Device 103 will continue to monitor for ongoing AF whenever device 103 determines that the sleep criterion is not met.
Various modifications, equivalent processes, as well as numerous applications to which the present invention may be amenable will be readily apparent to those of skill in the art to which the present invention is directed, upon review of the present specification. The claims are intended to cover such modifications and devices. | A patient-controlled system for temporarily disabling an electrical cardioverting therapy in order to prepare the patient psychologically and physiologically for the pain associated with electrical cardioversion therapy. In an example embodiment, the system includes a capacitive circuit capable of charging and discharging in order to apply the electrical therapy. The implanted medical device automatically causes the capacitive circuit to charge and discharge at least once within a selected period. The system includes a patient activator device that communicates with the implanted device. A disabling circuit is also included within the implanted medical device that temporarily disables the electrical therapy application in response to the patient activator device. The system further includes an alerting arrangement that alerts the patient activator device in response to the disabling circuit. An override circuit overrides the temporary disabling of the electrical therapy application in response to the patient being in a relaxed mode. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention, which is in the field of household utensils, pertains to a vegetable or fruit peeler that can be used more specifically for peeling asparagus, though not exclusively for said purpose.
2. The Prior Art
Currently-used peelers are generally composed of a handle, a cutting blade and one or two bars parallel to the blade, that can be called support or guide bars, because they are intended to press against the vegetable or fruit in order to guide the utensil appropriately, while limiting the thickness of the peels.
The most conventional model of a vegetable or fruit peeler is in the form of a sort of knife, having a handle unitary with a wide inwardly-curved blade made in one piece, divided into three parallel parts by two longitudinal slits, with the center part constituting a double-edged cutting blade, and the two side parts forming support bars.
The main problem with these utensils is that the peels often remain wedged in the slit(s) between the blade and the support bar(s). This problem is especially prevalent with irregularly-shaped or fibrous peels and is thus especially common in peeling asparagus. Peels wedged in the utensil must be removed using the hand not holding the utensil, which interferes with and slows down the peeling operation.
SUMMARY OF THE INVENTION
The present invention eliminates the aforementioned problem by providing an improved vegetable or fruit peeler allowing the user to employ only the hand holding the utensil for the easy and quick removal of any peels that may become wedged.
For this purpose, the object of the invention is a vegetable or fruit peeler composed in the known manner of a handle, a cutting blade and one or two support or guide bars parallel to the blade, wherein the blade and/or at least one support or guide bar form a unit that moves in translation towards the handle, and that can be retracted into the handle, so that the retraction of the mobile unit into the handle disengages the peels wedged between the blade and the support or guide bar(s).
In this way, the utensil user can make the cutting blade and/or the one or two support bars retract into the handle, using a simple and quick motion, as often as necessary during the peeling operation, so that the wedged peels are released and fall independently, by virtue of their own weight. The mobile unit is then returned, or returns on its own through the action of a spring or another elastic return mechanism, to its normal operating position, i.e., fully extended from the handle, and the peeling operation can be resumed immediately.
More specifically, the invention provides two embodiments for vegetable or fruit peelers having a cutting blade surrounded by two support or guide bars in the known manner.
In the first embodiment, the mobile unit that can be retracted into the handle is composed of the cutting blade and the two support or guide bars.
In the second embodiment, the mobile unit comprises the cutting blade and only one of the two support or guide bars, while the other support bar remains unitary with the handle.
The two embodiments below are possible for peelers endowed with a single support or guide bar.
In the first embodiment, the mobile unit that can be retracted into the handle is composed of the cutting blade and the single support or guide bar.
In the second embodiment, the mobile unit is composed of the cutting blade alone, while the single support bar remains unitary with the handle.
Advantageously, when one support bar remains unitary with the peeler handle, the bar comprises, at its end away from the handle, a rigid end piece extending perpendicularly to the "fixed" support bar, and having a mechanism to position the mobile unit cutting blade and support bar, if one exists, when the mobile unit is in its position fully extended from the handle. In the peeler's normal operating position, this arrangement provides the unit composed of the cutting blade and the support bar(s) the rigidity needed to produce peels having a uniform thickness, given that the thin and relatively flexible nature of the support bar(s) and especially the cutting blade makes them susceptible to bending when they are pressed against a vegetable or fruit in order to peel it.
In either of the above embodiments, the mobile unit that can be retracted into the handle, composed of the cutting blade and/or at least one support or guide bar, can comprise a stop provided for the manual activation of the mobile unit, so that the latter can be retracted into the handle, with a spring being mounted inside the handle to return the mobile unit to its position fully extended from the handle. The sliding of the mobile unit in the retracting direction is thus controlled by pushing the stop of this unit with the thumb or index finger of the hand holding the utensil, the hand still holding the handle with the other fingers, without having to change the position of the grip, while the mobile unit moves. After the peels are disengaged, it suffices to release the pressure of the finger on the stop, so that the return spring housed in the handle moves the mobile unit back to its normal operating position. Right-handed or left-handed persons may use the instrument in this manner, when mobile units composed of the cutting blade and one of the two support bars are involved.
When the user moves the mobile unit composed of the cutting blade and/or one of the support or guide bars by pressing the button with one of his fingers, the reaction could cause the other fingers holding the utensil to slip on the handle in the opposite direction. In order to hold the other fingers easily in place, another fixed stop is advantageously provided on the side of the handle opposite that of the stop unitary with the mobile unit, in order to keep in place the fingers other than the one acting on the first stop. In this way, when the index finger is used to move the mobile unit in translation, the second stop unitary with the handle will keep the thumb of the same hand, which tends to move in the opposite direction, in the proper position.
In another embodiment of the invention, the mobile unit that can be retracted into the handle, composed of the cutting blade and/or at least one support or guide bar, comprises a mechanical connection with a lever mounted pivotally on the handle, so that pressure exerted on the lever, towards or away from the handle, moves the mobile unit to its regular operating position, fully extended from the handle, or to its position retracted into the handle.
According to an initial option, the mobile unit is connected to a fixed point on the handle by means of a toggle lever composed of two rocker bars interconnected by an intermediary hinge pressing against the aforementioned lever, so that pressure exerted on the lever moving it towards the handle causes the mobile unit to move outside of the handle to its normal operating position, while a spring is mounted inside the handle to move the mobile unit to its retracted position inside the handle. In this case, the user can move the mobile unit to its operating position through the intermediary of the toggle lever, against the action of the spring, by pressing the lever with one of his fingers. To prevent the user from exerting constant pressure on the lever during the peeling operation, a small catch is preferably placed on the handle to hold the lever when the latter is placed against the handle. When the user wishes to remove the peels, he lifts the catch, which releases the lever and allows the spring to retract the mobile unit, with the toggle lever in this case displacing so as to move the handle lever away. A small wheel is advantageously provided at the intermediary hinge of the toggle lever to facilitate the latter's sliding on the lever when the mobile unit moves.
In one alternative, the mobile unit and the lever are mechanically connected by a wire, one end of which is attached to the mobile unit, passing over a first fixed pulley located towards the rear end of the handle, then over a second mobile pulley, held by the lever, and the other end of which is attached to the handle at a point so that, when the lever is moved away from the handle, the wire sliding or rolling over the pulleys moves the mobile unit into the handle, with a spring being mounted inside the handle to return the mobile unit to its position fully extended from the handle. The mobile unit is thus retracted into the handle by exerting traction on said unit through the intermediary of a wire selected so as to be sufficiently sturdy and flexible.
BRIEF DESCRIPTION OF THE DRAWINGS
In any event, the invention will be more clearly understood through the description below, with reference to the attached schematic drawings illustrating a few embodiments of the vegetable or fruit peeler, given as non-restrictive examples, in which:
FIG. 1 is a perspective view of an initial embodiment of a peeler according to the present invention;
FIG. 2 is highly schematic cross section showing the mechanism of the peeler in FIG. 1;
FIGS. 3 and 4 illustrate the use of the peeler in FIGS. 1 and 2 by a right-handed person;
FIG. 5 illustrates the use of the same peeler by a left-handed person;
FIG. 6 is a view of a second embodiment of the invention, similar to FIG. 2;
FIG. 7 is a view similar to those preceding, illustrating an alternative version of the peeler in FIG. 6;
FIG. 8 is a perspective view of a last embodiment of the peeler;
FIG. 9 is a longitudinal cross section of the peeler in FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In all embodiments shown in the drawings, the vegetable or fruit peeler comprises a handle 1, a cutting blade 2 and, on either side of blade 2, two support bars, respectively 3 and 4, parallel to each other and to blade 2. First of all, concentrating exclusively on FIGS. 1 to 7, one of the support bars 3 is attached securely to handle 1, with the other support bar 4 and blade 2 forming a retractable mobile unit 5 that can be moved in translation in the longitudinal direction of handle 1 as shown by double arrow 6, and can be retracted into the handle 1, the latter being hollow so that it can accommodate and guide mobile unit 5.
In the embodiment shown in FIGS. 1 and 2, the mobile unit 5 composed of blade 2 and support bar 4 also comprises in its rear part a side stop 7 so that it can be activated manually by the thumb or index finger of the hand holding the utensil. Mobile unit 5 may thus be pulled back and retracted, against the action of return spring 8 housed in handle 1, which returns mobile unit 5 to its normal operating position, fully extended from handle 1. Handle 1 bears another stop 9 on the side opposite the first stop 7, to hold the fingers other than the one acting on said first stop 7, and thus prevent the hand from slipping.
As shown primarily in FIG. 1, at its end away from handle 1, fixed support bar 3 bears a rigid end piece 10 which extends perpendicularly to the fixed support bar 3. End piece 10 contains two openings or grooves 11 and 12, provided to accommodate respectively the free ends of blade 2 and support bar 4 of mobile unit 5, when the latter is in its position fully extended from handle 1. This reinforces the peeler, preventing cutting blade 2 and support bar 4 from bending undesirably in the utensil's regular operating position.
When the utensil is in use, and when peels are wedged between blade 2 and either of the two support bars 3 and 4, it suffices to retract mobile unit 5 into handle 1 by acting on button 7, in order to release the peels, Which are then removed by the simple effect of gravity, being stopped by the "fixed" wall located at the end of handle 1, through which mobile unit 5 passes. Next, by releasing stop 7, return spring 8 is allowed to move mobile unit 5 back to its operating position so that the peeling in progress can continue.
FIGS. 3 and 4 illustrate the use of the peeler described above by a right-handed person, successively showing the normal operating position and the retracted position for removing the peels. FIG. 5 illustrates the same peeler held by a left-handed person.
FIG. 6 shows another embodiment, which also comprises a mobile unit 5 that can be retracted into handle 1, composed of cutting blade 2 and one 4 of the two support bars 3 and 4. The rear part of mobile unit 5 in this case is connected to a fixed point 13 of handle 1 located in the median area thereof, by a toggle lever 14, which cooperates with a lever 15 hinging on handle 1 at point 16, located at the rear end of the handle 1.
More specifically, toggle lever 14 comprises a first rocker bar 17 hinging at point 18 on mobile unit 5, and a second rocker bar 19 hinging at point 13 on handle 1, with the two rocker bars 17 and 19 being interconnected by intermediary hinge 20. A small wheel 21, provided at intermediary hinge 20, presses against one surface of lever 15, rolling on this surface.
Spring 22 stretched between the rear end of mobile unit 5 and a fixed point 23 of handle 1 causes mobile unit 5 to retract into handle 1. Conversely, pressure exerted on lever 15 in the direction of arrow 24, thus moving lever 15 towards handle 1, causes mobile unit 5 to move to its position fully extended from handle 1, through the intermediary of toggle lever 14. A small catch 25 is provided to hold lever 15 in its position closest to handle 1, corresponding to the position mobile unit 5 occupies during the normal operation of the peeler.
In this case, when wedged peels are to be removed, lever 15 must be released by lifting catch 25. The action of spring 22 then causes mobile unit 5 to retract into the handle. At the same time, toggle lever 14 moves lever 15 aWay from handle 1. Next, a simple push on lever 15 in the direction of arrow 24 moves the lever against handle 1 and returns mobile unit 5 to operating position.
In one alternative illustrated in FIG. 7, mobile unit 5 is connected mechanically to lever 15, still hinged at 16 to the rear end of handle 1 by means of a solid, flexible wire running along a path indicated by a solid line. A first end of wire 26 is attached to the rear part of mobile unit 5 at point 27. Past attachment point 27, wire 26 first extends parallel to handle 1, and runs over a first fixed pulley 28 located at the rear end of handle 1, at hinge 16 of lever 15. Wire 26 next follows the direction of lever 15, and passes over a second mobile pulley 29, held by lever 15. The other end of wire 26 is attached to handle 1 at a fixed point 30 located in the front of said handle 1.
In this case, return spring 8 housed inside handle 1 acts on mobile unit 5 as in the first embodiment described, i.e., it pushes said mobile unit 5 back to its normal operating position, fully extended from handle 1. A position of lever 15 brought towards handle 1, corresponds to the position of mobile unit 5, by means of the connection provided by wire 26. As in the preceding embodiment, a small catch 25 can hold lever 15 in said position.
To remove wedged peels, if necessary, the user releases lever 15, exerting traction according to arrow 31 on the lever 15, moving lever 15 away from handle 1. By sliding or rolling over the two pulleys 28 and 29, wire 26 then pulls mobile unit 5 into handle 1, thus causing the mobile unit 5 to retract. As soon as lever 15 is released, return spring 8 can bring mobile unit 5 back to its extended position, with lever 15 being moved back against handle 1.
FIGS. 8 and 9 show yet another embodiment wherein cutting blade 2 and the two support bars 3 and 4 surrounding said blade 2 are all mobile and can be retracted simultaneously into handle 1. Mobile unit 5 is thus composed of blade 2 and the two bars 3 and 4, interconnected by a block 32 mounted slidingly inside the hollow part of handle 1, which also houses return spring 8. As in the first embodiment, in this case again, mobile unit 5 comprises a stop 7 so that said unit can be pulled backwards, against the action of spring 8, to release the peels.
Of course, the invention is not limited solely to the embodiments of said vegetable or fruit peeler described as examples above; on the contrary, it encompasses all alternative embodiments and applications following the same principle. Thus, the peeler can also be designed in particular with a cutting blade and a single support bar, and, in this case, the single support bar may be either unitary with the handle, so that the mobile unit is limited to the blade, or unitary with the blade, so as to constitute the mobile unit together with the blade. Alternatively, the mobile assembly may be constituted by the support bar, whereas the cutting blade is integral with the handle. Further, in the case where the peeler comprises two support bars, the mobile assembly can be constituted by the two support bars, where the cutting blade is integral with the handle.
The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. | A household utensil, in particular a fruit or vegetable peeler is composed of a handle, a cutting blade and two support bars parallel to the blade. The blade and at least one of the support bars form a unit which moves in translation towards the handle and can be retracted into the handle. The retraction of the mobile unit into the handle releases the peels wedged between the blade and the support bars. The present invention is particularly useful for peeling asparagus. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation application of copending U.S. patent application Ser. No. 12/387,594, filed on May 6, 2009, which is a Continuation-In-Part of U.S. application Ser. No. 11/796,920, filed May 1, 2007. The disclosures of all of these U.S. patent applications are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a computer designed for mobile use.
BACKGROUND OF THE INVENTION
[0003] Bag computers are composed of a bag and computer joined so that the display panel pivots around the top front end of the bag so it can lay approximately flat against the bag front when stored or pivot with its display facing outward into the line of sight of the operator when in use. There may be a keyboard lower down on the bag front and there may be manual controls on the back of the display panel.
[0004] The bag computer was described in application Ser. No. 11/796,920. This application is a continuation on those inventions.
[0005] One characteristic of the most popular computers is division into components. This allows the computer owner to buy or replaces less expensive individual components when needed. Choice can be made between various prices and makers so the owner can optimize the result of his array of options. Manufacturers, as well, may benefit from being able to concentrate of the production of one type of component. This invention aims to build on the bag computer concept by encouraging owner replaceable components for bag computers.
BRIEF DESCRIPTION OF THE INVENTION
[0006] A bag computer is a bag with a display panel pivotally attached to so that the display panel can pivot from a storage position approximately flat against the bag's front wall to an operating position away from the bag so that the display is in the line of sight of the operator/wearer and he can view the display. The display panel may be attached near the junction of the top and front walls so that the display is as near as possible to the operator/wearer and have the greatest apparent display size. There may be a cover and this may have a manual input device, such as a keyboard, on the inside surface so that the input devices is hidden when the cover is closed and covers the display but available for use when the cover flap is opened. The cover may pivot near the center of the bag's front and close by pivoting up and attaching to attachments near the top of the bag. On the back side of the display panel opposite the display, in other words facing downward as the operators views the display, there may be controls, such as a touch pad, that may be operated with the fingers while holding the display panel. The bag computer's computing unit may be in the display panel or may be mounted separately to the inside or outside of the bag. The majority of the bag interior is available for everyday cargo or peripherals which are accessible though an opening in the bag's top wall.
[0007] The display panel may be removable from the bag. This may be done using a pivoting computer equipment mount (PCEM) which is comprised of a bag part and a display panel part which have complimentary attachments. One or both of these parts may include the hinge means or be part of the hinge means which allows the display to pivot on the bag.
[0008] The PCEMs hinge means may be able to hold any angular position relative to the bag front. Instead, the display panel position may be maintained with a display panel prop which removably spans between the bag front and display panel back.
[0009] In addition to the display, the display panel may have controls, display panel prop holders or finger guides. There may be a camera or communication antenna on the distal edge of the display panel (opposite the PCEM).
[0010] To further divide the bag computer into components, the display panel may be divided into a front side display panel portion with display and back side display panel portion with controls along a plane parallel to the display panel front and back sides.
[0011] The two display panel portions may be attached to each other directly with the display panel part of the PCEM fixed to one or the other display panel portion. Alternatively, the edge area of the two display panel portions may work in combination to form the display panel part of the PCEM.
[0012] There may be a fastening frame to hold the two display panel portions together and the display panel part of the PCEM is located on either the front side or back side display panel portion. Alternatively, there may be an attachment frame which holds the two display panel portions together and also includes on the attachment frame the display panel part of the PCEM to connect the three parts to the bag. Either type or frame may include display prop fixtures, bumpers to contact the bag front or finger guides for the back side controls or prop fixtures.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1 The bag computer is seen here in storage position with its display panel parallel to and adjacent to the bag's front wall and the cover over the display panel.
[0014] FIG. 2 Here the bag computer has its display panel in the same position as in FIG. 1 but the cover is open.
[0015] FIG. 3 Here the bag computer is in operating position with its diaply pivoted out into the line of sight of the wearer/operator.
[0016] FIG. 4A This is a front view of a manikin wearing and operating the bag computer. His hands are manipulating the controls on the back side of the display panel.
[0017] FIG. 4B This is a side view of a manikin wearing and operating the bag computer. His hands are manipulating the controls on the back side of the display panel.
[0018] FIG. 5 This is a detail of the parts of a bag computer including how the display panel is removable from the bag. The display is on the front side facing up.
[0019] FIG. 6A This is a figure of the display panel is tipped to show its back side including controls, tactile finger guides, bumpers, display prop holders and other details.
[0020] FIG. 6B This is a template or finger guide frame which fits the display panel and adds tactile finger guides, bumpers, display prop holders and other details.
[0021] FIG. 7A This is a front side view of the display panel showing details.
[0022] FIG. 7B This is a side edge view of the display panel showing details.
[0023] FIG. 7C This is a back side view of the display panel showing details.
[0024] FIG. 7D This is a side edge view of the display panel showing how it may be divided into a front side panel portion and a back side panel portion. In this embodiment the two parts are levered together with attachments.
[0025] FIG. 8A This view of the display panel shows an embodiment where the front and back side panel portions are attached using attachments found on one panel portion and matching the other portion. The mounting attachments to match the bag are found on the front side display panel portion.
[0026] FIG. 8B This shows the same parts as FIG. 8A but viewed from below so the display panel back side can be seen.
[0027] FIG. 9A This view of the display panel shows an embodiment where the front and back side panel portions are attached using attachments found on one panel portion and matching the other portion. The mounting attachments to match the bag are found on the back side display panel portion.
[0028] FIG. 9B This shows the same parts as FIG. 9A but viewed from below so the display panel back side can be seen.
[0029] FIG. 10A In this view the front and back side panel portions are attached using a separate fastening frame which, in this case, includes openings, tactile finger guides, bumpers, display prop holders and other details.
[0030] FIG. 10B This shows the same parts as FIG. 9A but viewed from below so the display panel back side can be seen.
[0031] FIG. 11A In this embodiment an attachment frame has an attachment means to connect with the bag. The attachment frame accepts slide-in front and back side panel portions.
[0032] FIG. 11B This shows the same parts as FIG. 10A but viewed from below so the display panel back side can be seen.
[0033] FIG. 12 In this case a attachment frame is also used to attach to the bag while accepting slide-in front and back side panel portions. Here, however, the openings, tactile finger guides, bumpers, display prop holders are included as part of the frame.
DETAILED DESCRIPTION OF THE INVENTION
[0034] A bag computer is a bag with a display panel, including input/output devices such as a display and graphic user input device, pivotally attached to the exterior of the bag so it may pivot horizontally from a storage position parallel to and adjacent the bag's front wall to an operating position away from the bag's front wall where the wearer/operator may view it. The bag computer's computing unit may be found in the display panel or elsewhere mounted to the bag's interior or exterior and is electrically connected to the display panel. A manual character input device such as a keyboard or electronic write pad may also be pivotally attached to the bag front. The bag computer may be seen as a system of components to facility the mobile use of a computer.
[0035] FIGS. 1 , 2 and 3 show how a bag computer is deployed and used. As shown in FIG. 1 the display panel, when pivotally attached to the bag 1 , is stored against the bag front 45 and may be covered with a cover, such as a cover flap 31 or rigid shaped cover. Shown in FIG. 2 , when the cover 31 is repositioned, the display panel 22 is exposed for use. Here it can be seen that the display panel is in storage position with its front side 3 , including display 11 , and back side approximately parallel to the bag front wall exterior 45 and its back side adjacent to the exterior of the bag front wall. In FIG. 3 , the display panel 22 is pivoted approximately around the junction of the front and top bag walls 23 to an operating position away from the bag front wall 45 with its display 11 properly oriented and in the line of sight of the operator/bag wearer so the display can be viewed and used. The back side of the display panel may have controls such as one or more touch pads, switched, or buttons, for operating the computer with fingers while holding and viewing the display on the display panel. The bag may have an opening 49 in its top wall to access the bag interior where peripherals or miscellaneous cargo may be stored. A keyboard 29 can be seen on the inside surface of the cover.
[0036] FIG. 4A , frontal view, and FIG. 4B , profile view, show the bag computer being worn by a manikin 46 . The bag shoulder strap 47 holds the bag computer 2 to the operator so the computer will not fall and he can use two hands for operating the display panel 22 back side 4 controls or operate the manual character input device, in this case a keyboard 29 . The display is in the line of sight 48 of the bag computer wearer.
[0037] The display panel may be removable from the bag. In this case, the bag and display panel may be pivotally joined with complimentary mounting attachments on the bag and display panel, also collectively known as “pivoting computer equipment mounts” (PCEM). As shown in FIG. 5 , one or more bag part PCEMs, also known as bag mounting attachments 59 , are found on the bag 1 and one or more complimentary display panel part PCEMs, also known as display panel mounting attachments 58 , are found on the display panel. The hinge means which allows pivoting may be part of the bag mounting attachment or part of the display panel mounting attachment or part of both. The PCEM leaves the back side of the display panel unobstructed so controls located there can be used The bag mounting attachments may be located at or near the junction 23 of the bag's front wall 45 and top wall 30 and the display panel mounting attachments may be located at or near the attachment edge 5 of the display panel.
[0038] The actual character of the PCEM may vary although all combinations serve to pivotally attach the display panel to the bag so that the display panel may rest in storage position with its front and back sides approximately parallel to and adjacent to the bag front wall or may be pivoted to an operating position in the line of sight of the operator/wearer for operation.
[0039] The PCEM hinge means may be capable of holding the angular position between the display panel and bag front wall with, for example, a ratchet or friction hinge. Instead, as in the case where the PCEM hinge means is a flexible fabric flap, the angular position between the display panel and bag front wall may be maintained using a display panel prop assembly 67 designed to extending between the bag front wall and display panel back side and temporarily support the display panel in one or more viewing positions.
[0040] Because the display panel and bag have different life times, the display panel and bag may be separated for replacement or upgrading. The display panel 22 is of panel-like shape having front side 3 with display 11 , an opposite back side which may have controls, an attachment edge 5 closest to the bag, a distal edge 6 opposite the attachment edge and two side edges 7 . On or near the attachment edge there may be one or more display panel mounting attachments 58 which are the display panel part of the PCEM and are complimentary to bag mounting attachments located on the bag and pivotally connect the bag and display panel.
[0041] The bag computer's computing equipment, such as the computing unit, batteries and communication equipment may be located in the display panel. Alternatively, some or all of the computer equipment may be located on the exterior or in the interior of the bag and connected electrically with the display panel by, for example, an electrical wire 8 and associated plug(s) designed to lead through an opening 47 in the bag associated with the front wall or bag mounting attachment. The electrical wire and plug may be attached to the display panel and be of specific length, size and shape to connect the display panel and computing unit while they are installed to the bag. The computing unit may be removably mounted to a bag mounting assembly fixed to the inside surface of the bag's front. Much of the remainder of the bag's interior may be left unoccupied so it may be used to hold miscellaneous cargo and/or peripherals.
[0042] FIG. 6A shows the back side 4 of the display panel 22 where controls may be found and be available for use when the operator holds and uses the display panel while it is attached to the bag. These controls may include one or more touch pads 9 , clickers, buttons 50 , slides or other means to communicate with the computing unit with the hands.
[0043] The back side of the display panel may have prop holder, such as holes, sockets 51 , clips 52 , sliding fixtures, guides, runway, pins, or hinge means with mount to match and be complimentary to a display panel's prop bar which extends between the display panel and bag front and is used to support the display panel at one or more angles relative to the bag front wall.
[0044] There may be several display panel back side prop holders properly spaced and angled to prop up the display panel in the most commonly used positions. Different types of holders may be used to accommodate holding the display panel at various horizontal angles versus holding the display panel vertical and parallel to the bag front and prop bar. There may be molded-in prop position guides 53 to help the fingers engage the bar end into the right prop position on the back of the display with the hands without looking. The display panel may have a means of spacing the display panel back from the bag front, such as display panel edges extended toward the bag front beyond the plane of the display panel back side, legs, bumpers 54 or display panel mounting attachment extending toward the bag front from the display panel back side or a recessed area in the display panel back side to matching the prop holders and prop bar, so that the display panel, when in storage position, may lay approximately flat against the bag without interference from the display panel prop assembly.
[0045] The display panel back side may include finger guides 55 around or near specific controls to assist in finding these controls without looking. The finger guides may be in the form of molded in ridges around or near controls. As shown in FIG. 6B , a removable finger guide template 56 or finger guide frame with tactile finger guide 55 features may be used to indicate control positions. The finger guide template or frame may be rigid and include clips to attach it to the display panel or may be thin and attach to the display panel with adhesive or attachments that are part of the display panel. Display panel prop holders 57 may be included in a finger guide template or finger guide frame 56 which may be removable from the display panel. The finger guide and display panel prop holder may be combined on the same finger guide template or frame.
[0046] Shown in FIGS. 7A , 7 B, 7 C and 7 D, to further divide the bag computer system into components, the display panel may be divided into two display panel portions along a plane parallel to the display panel front side and back side. The two portions are the front side display panel portion 37 and back side display panel portion 36 . Each display panel portion has an outward facing surface 39 and an inward facing surface 40 and four edges. The outward facing surface of the front side display panel portion includes the display 11 and the outward facing surface back side display panel portion includes controls, for example, a touch pad 9 or other pointing device, switches or buttons 50 . When the two display panel portions are assembled when forming the display panel, their inward facing surfaces are adjacent. The display may include a touch screen. The outward facing surface of the back side display panel portion may be mostly touchpad with a finger guide overlaying it and defining programmable function areas. The outward facing surface back side display panel portion may include holders for a display panel prop 60 . Either display panel portions may be replaced whenever desired. The front side display panel portion and back side display panel portion may be held together with an attachment means. The two display panel portions are electrically connected with the computing unit and this connection may be located anywhere on or near the attachment edge of the display panel. The connection may be a wire with plug 10 to match the computing unit.
[0047] In one embodiment the attachment means holding the two display panel portions together may be comprised of a first attachment pair 41 on one adjacent edge of the two display panel portions and used to lever the panels together while a second attachment pair 42 hold the opposite adjacent edges of the display panel portions together. Examples of the first attachment pair use to lever the display panel portions together may include a hook, plug, ledge or socket. Examples of the second attachment pair include a clamp with screw, clip or other attachment. The display panel mounting attachment may be attached to either of the display panel portions. Instead, the display panel mounting attachment 58 may be formed by a combination of adjacent edges of the two display panel portions, for example, where the adjacent edges of the panel portions act as two jaws 58 to clamp the bag mounting attachments between them and hold the display panel to the bag.
[0048] The two display panel portions may have an electrical connection 10 between them. The electrical connection may be combined with one of the attachment pairs. Alternatively, each display panel portion may have an independent electrical connection 8 connecting the display panel portion with a separate computing unit.
[0049] In a second embodiment the attachment means holding the two display panel portions may be comprised of attachments on one or both of the two display panel portions which hold the two display panel portions together. The attachments may be clips, channels to slide on matching panel edges or rails, pins, or other means to attach the two panel portions. As shown in FIG. 8A , a view of the two parts from an angle showing upper surfaces, and in FIG. 8B , a view of the two parts from an angle showing lower surfaces, attachment clips 61 may be included on the back side display panel portion 36 and these match the body shape of the front side display panel portion 37 to hold the two parts together. Although, in this case, the display panel mounting attachment are part of the front side display panel portion, the display panel mounting attachment 58 may be located on either of the two display panel portions. The two display panel portions may have an electrical connection 10 between them. Alternatively, each display panel portion may have an independent electrical connection 8 connecting the display panel portion with a separate computing unit.
[0050] Shown in FIGS. 9A and 9B , the display panel mounting attachment 58 is part of the back side display panel portion 36 and the front side display panel portion 37 is removable. Again, attachments 61 , such as channels to slide on matching panel edges or rails or clips, may be used to physically connect the two panel portion and an electrical connection 10 may be used to electrically connect the two panel portions. There may be a separate electrical connection 8 to lead to the computing unit attached to the bag.
[0051] In a variation on this embodiment, shown in FIGS. 10A and 10B , the attachment means holding the two display panel portions together may be comprised of a separate fastening frame 62 that includes attachments 61 which match and hold the back side display panel portion 36 and the front side display panel portion 37 together. The fastening frame may also include finger guides with guiding features such as openings 63 , bumps, ridges 64 or other features in relief, to help the operator feel the position of controls on the display panel back side. The fastening frame may also include prop holders 66 or bumpers 65 . The display panel mounting attachment may be located on fastening frame or either of the display panel portions. The two display panel portions may have an electrical connection 10 between them. Alternatively, each display panel portion may have an independent electrical connection 8 connecting the display panel portion with a separate computing unit.
[0052] In a third embodiment, shown in FIGS. 11A , 11 B and 12 the attachment means holding the two display panel portions together may be comprised of a separate attachment frame 62 designed to fit and hold the back side display panel portion 36 and the front side display panel portion 37 together and to the bag. The attachment frame has an attachment edge which has the display panel mounting attachment 58 which attaches the frame to the bag. The attachment frame has holding parts, such as receptacles, guides, rails 68 or gripping arms, to hold and retain the display panel portions in the attachment frame. The holding parts may match the shape of or complimentary attachments on the display panel portions.
[0053] The attachment frame may be box-like with one or more openings 63 to allow the display panel portions to be installed and to allow access to the display panel portions for operation after they are installed.
[0054] The display panel portions may slide into the receptacles of the attachment frame from one edge and in a direction parallel to the plane of the display panel front and back surface. Any edge of the attachment frame may be used for installation.
[0055] Electrical connection may be by plug between each display panel portion and the computing unit. Alternatively, there may be an electrical connection 10 between each of the display panel portions and the attachment frame. In this case, the attachment frame has a separate electrical connection 8 between the attachment frame and the external computing unit. In another alternative, the two panel portions may electrically connected directly with one of the display panel portions electrical connected to the attachment frame.
[0056] Finger guides, bumpers and prop holders may be included with the back side display panel portion. Alternatively, as shown in FIG. 12 , the finger guides 64 , bumpers 65 and prop holders 66 may be included as part of the attachment frame 62 with the back side display panel portion 36 being operated through finger guide openings 63 in the frame. The attachment frame may include the display panel mounting attachment 58 . The attachment frame holds the front side display panel portion 37 and the front side display panel portion. | Disclosed is an improvement to the bag computer of application Ser. No. 11/796,920. The bag computer has a pivoting display panel near its top front which can store against the bag front or pivot into the line of sight of the bag computer wearer/operator. The display panel may have controls on the side opposite the display. To gain advantage through multiple components, the display panel may be divided into a front portion with display and back portion with controls. Ways to divide and assemble these display panel components are described and include: 1) direct attachment between the two portions with one portion connecting to the bag; 2) a fastening frame attaching the two portions with one portion connecting to the bag; 3) an attachment frame which connects to the bag and accepts the two portions. | 6 |
BACKGROUND OF THE INVENTION
The invention relates to a paving-stone set, especially a concrete paving-stone set for constructing garden layouts, paths or the like with paving stones of which the side faces and upper and lower faces are made plane and the transitional region between a side face and the upper or lower faces is made substantially sharp-edged or rounded.
The external shaping of concrete paving stones is governed by both technical and visual factors. Thus, paving stones with plane side faces are produced in a square or rectangular basic chape, so that the paving stones, when laid in a composite structure over the entire surface, are supported against one another, thus ensuring a firm bond. Moreover, during laying, directional stability is improved in comparison with stones having curved outer contours, and a more efficient utilization of shape and of area is guaranteed. Furthermore, the advantage of plane outer contours is that the molds for producing the paving stones are cheaper. In addition, plane outer faces guarantee the greatest possible bundling capacity.
However, a laid surface with completely plane outer contours gives the observer a very monotonous impression, and because of this known paving stones (U.S. Pat. No. 4,572,699) are provided with a specific paving-stone head structure. This can be obtained by means of rounded edges, drawn-down corner regions, wavy recesses or the like.
Another advantage of plane side faces is that the stones can be laid very easily in a composite structure, since the side faces are supported against one another. Furthermore, good directional stability and alignment of the stones are possible during laying. However, the disadvantage of plane side faces is that between the individual paving stones there is little free space for water to run off or to seep away into the subsoil or for the possible growing of grass. Known paving stones are therefore sometimes given curved outer contours. But this entails the disadvantages mentioned above.
The object on which the invention is based is to provide a paving stone with substantially plane outer contours, that is to say an upper and a lower face and side faces, but of shaping which allows existence interspaces between the paving stones laid against one another. At the same time, the shaping will be such that a completely irregular appearance is obtained in the laid state.
SUMMARY OF THE INVENTION
According to the invention, this object is achieved because at least two side faces located opposite one another or adjoining one another are made rounded towards at least one corner region, the rounding, as seen in plan view, being shaped as a curve with a radius of curvature decreasing constantly towards the corner regions (this is known as a clothoid shape, which is also known as Cornu's spiral).
The advantage of the paving stone according to the invention is that the plane side faces makes it possible to ensure good laying in a composite structure, since the stones butt against one another in the laid state. The rounding in the form of a curve which decreases constantly towards the corner regions (clothoid) gives the stone shape a completely irregular appearance, thereby avoiding a monotonous aspect. At the same time, the clothoids are distributed completely irregularly in the particular corner regions of the paving stones, so that virtually every paving stone has a different effect. Also, one and the same paving stone itself has a different effect, depending on where the clothoid comes to rest in the laid composite structure, that is to say as a result of the rotation of the paving stone. The recess created as a result of the rounding in the corner region then allows water to flow off easily and, if appropriate, make it possible to grow plants or grass in this region. If the rounding were made as a conventional rounding of constant radius or simply as a constant bevel, the stone shape would not guarantee the desired visual effect, together with the associated possibilities of good water flow-off and growth of plants. In particular, such a paving stone would also always have the same effect, when rotated.
Advantageous developments and improvements of the paving-stone set indicated in the above are contemplated as being within the scope of the present invention.
The clothoid-shaped curvature is restricted to approximately 1/4 to 1/6 of the total side length. As a result, the main side face remains plane, thus affording the associated advantages during laying and ensuring the associated stability of the laid composite surface.
At least one corner of the paving stone between two side faces can preferably be made sharp-edged and right-angled. This serves for a clear visual delimitation in relation to the clothoid-shaped curvature in the remaining corner regions. Furthermore, a right-angled corner can utilize the area in edge regions in the most efficient way possible.
According to another aspect of the invention, the upper and lower edge between the upper face or lower face and the side faces is made sharp-edged, this sharp edge can also be broken irregularly.
Because the side faces are curved in the form of a clothoid in the corner regions, the paving stone also acquires a crowned rustic visual appearance, this partly being reinforced by the broken edges. At the same time, because of the plane upper face, it is easy to walk on the laid surface and easy to clean it, in particular to clear it of snow, etc, a good grip still being guaranteed by the interspaces formed by the clothoids.
When concrete paving stones are produced in production molds, the transistion between the lower face and side faces is usually made sharp-edged. So that both the side which is the lower during production in the production mold and the upper side subjected to the force of the male die can be used equally as the upper visible side in the laid state, the continuous edges between these two faces and the side faces are each made sharp-edged. The sharp edge is then broken in order to five a rustic appearance. This is achieved by uncontrolled tipping from the motor truck or by means of a special revolving drum, in which the stones knock against one another.
In another embodiment of the present invention, the structure of the face which is the lower in the production mold is made coarser, because of the coarser back concrete, than the upper face which is subjected to the force of the male die of the molding machine and in which a finer facing concrete of another composition is used. Then, if both sides are used at random during laying, this gives a looser appearance, if appropriate with different color structure as a result of the addition of coloring agents to the facing concrete and back concrete.
In another embodiment of the present invention, the paving stones are constructed according to the building-block system, with a square standard stone as seen in plan view, a larger rectangular 11/2-size stone as seen in plan view, and with a smaller rectangular half-size stone as seen in plan view.
Of course, the clothoid can also be formed by traversing a polygonal course.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are illustrated in the drawing and explained in detail in the following description. In the drawing:
FIGS. 1a and 1b show a larger rectangular stone in plan view and in a perspective view respectively,
FIGS. 2a and 2b show a paving stone of square horizontal projection in plan view and in perspective view respectively,
FIGS. 3a and 3b show a smaller paving stone of rectangular cross-section in plan view and in perspective view respectively, and
FIG. 4 shows a plan view of a laid surface or a die mold for producing the paving stones.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1a shows a paving stone (1) which is rectangular in its basic cross-section and which has a length of L 1 =238 mm and a width of b 1 =178 mm. In conformity with this, the side length of the square stone (2) according to FIG. 2a amounts to L 2 =b 2 =178 mm. The length of the small rectangular stone (3) according to FIG. 3a amounts to L 3 =178 mm and the width is b 3 =88 mm. The lengths b 1 , b 2 , L 2 and L 3 are accordingly the same. The height of the paving stones (1), (2) and (3) amounts to approximately h≈70 mm.
FIG. 1a shows the various possibilities for forming the curves at the side faces (8 to 11) in the corner regions. The corner regions are designated by the reference symbols (4 to 7). At the same time, the actual shaping is marked by an unbroken line, and the shaping which is also possible, if appropriate, is marked by a dot-and-dash line.
In the paving stone (1) (FIG. 1a), the corner (4) is designed as a so-called clothoid (31), that is to say the plane side face (8) has, both towards the left-hand corner region (4) and towards the right-hand corner region (5), a rounding which, as seen in plan view, is shaped as a curve with radii of curvature (R 4 , R 4 ', R 4 " and R 5 , R 5 ', R 5 ") decreasing constantly towards the corner regions. In the corner region (4), for example, the clothoid (31) starts on the side face (8) at a length L 4 ≈40 mm with a radius R 4 '≈81 mm and ends on the adjoining plane side face (9) with a length of L 5 ≈12 mm and a radius of R 4 "≈13 mm. Accordingly, the radius R 4 becomes constantly smaller towards the corner region, this being characteristic for this shaping.
The corner (5) in FIG. 1a has, for example a clothoid (31) which starts on the side face (8) at a distance L 6 ≈45 mm from the corner region and ends approximately at a length L 7 ≈7 mm in the side face (10). The radius at the start of the clothoid (31) is approximately R 5 '≈165 mm and ends in the corner region at R 5 "≈7.5 mm.
The corner region (6) of the stone shape (1) in FIG. 1a is designed as a right-angled sharp edge (32) with a rounding of R 6 ≈4 mm.
The corner region (7) of the stone shape in FIG. 1a has a clothoid form which starts on the longer side face (11) at a distance of L 8 ≈40 mm and ends laterally in the side face (10) at a distance L 9 ≈10 mm. The maximum radius amounts to, for example, R 7 '≈93 mm, and the minimum radius amounts to R 7 "≈11 mm.
The corner region indicated by dot-and-dash lines in the corner regions (4 to 7) in FIG. 1 represent alternative forms of construction of the clothoids (31') and of the right-angled construction (32') of the corner regions. Thus, the radii of the clothoids (31, 31') can assume highly varied values for different shapes.
The paving stone (2) of rectangular cross-section, shown in FIG. 2a, has corner regions (12 to 15) which are of a basic design similar to or the same as that of the corner regions (4 to 7) of the paving stone (1) in FIG. 1a. Thus, in the exemplary embodiment according to FIG. 2a, clothoids (31) are provided in the corner regions (12, 14, 15), whilst the corner (13) is made right-angled (32).
The same is true of the smaller rectangular paving stone (3) shown in FIG. 3a, with the corner regions (16 to 19), the corner region (18) of the paving stone (3) once again being made right-angled (32) without the construction of a clothoid. The lengths of the clothoids (31) are designated by L 4 , L 6 and L 8 according to the design in FIG. 1a.
As mentioned, the clothoids (31, 31') can have different starting and end radii. The clothoids (31) starts in each case on a side face at a length of L 4 , L 6 , L 8 of 1/4 to 1/6 of the total length L 1 , b 1 ; L 2 , b 2 ; L 3 , b 3 ) of the particular side face.
FIG. 4 shows the different types of paving stones to be formed from FIGS. 1a to 3a. The different types are identified by the type designation A to J, and the paving stones A' to J' illustrated are formed as a result of a rotation of the paving stone through 180° or a mirror-image representation of the stones A to J. The lower face and the upper face of the paving stone can be used equally as the visible face in the laid state.
The illustration in FIG. 4 also serves to show a laid surface, and for the sake of greater clarity there are distances between the side faces touching one another. In the laid state, the particular side faces are in contact with one another. It can be seen clearly from the illustration in FIG. 4 that marked recesses or cavities (37) are obtained in the corner regions in the zone of the clothoids, particularly also when several clothoids (31) of adjacent stones meet in the corner regions. This results in a sufficiently large gap (37) for water to flow off or, if appropriate, for growing grass on these part surfaces.
The illustration according to FIG. 4 can also serve to show the initial mold or die mold for producing the individual stone shapes or machine shapes with the best possible utilization of the mold area, each die mold being composed of the various stone shapes, as shown in FIG. 4. This guarantees that, during each production operation, the greatly varying stone shapes A to J or A' to J' are produced.
FIGS. 1b to 3b show the stone shapes according to FIGS. 1a to 3a in perspective. The larger rectangular stone (1) has a shaping as designated by A' in FIG. 4, that is to say, as seen in plan view the stone has a clothoid (31) only in the upper right-hand corner region (20) and in the lower left-hand corner region (21). The other two corner regions (22, 23) are made right-angled (32), that is to say the side faces (10' and 11') meet at right angles. This is also true of the side faces (8' and 9').
Of the stone shape in FIG. 1b, the continuous sharp-edged broken upper edge (38) between the upper visible face (24) and the side faces (8' and 10') is also shown. The same applies to the continuous lower edge (25) to the invisible lower face, this likewise being made continuously sharp-edged and broken, so that the stone can be turned over easily. The broken places (26) are obtained by knocking off the otherwise continuous sharp edge (38, 25) when the paving stones are tipped off from a motor truck onto the ground. However, the paving stones can also be knocked against one another in a drum, so that the edges break irregularly.
The square paving stones (2') and smaller rectangular paving stones (3') shown in FIGS. 2b and 3b respectively have basically the same design as the paving stone (1') in FIG. 1b. The paving stone (2') has clothoids (31) in the corner regions (28 to 30), whilst the corner region (27) is designed as a right-angled corner (32).
The same is true of the corner regions (34 and 36) of the paving stone (3') in FIG. 3b, which are designed as clothoids (31), whilst the other two corner regions (33, 35) are designed as right-angled corners (32). | A paving stone set includes a square paving-stone, a larger rectangular paving-stone and a smaller rectangular paving-stone. Each of the paving stones has generally planar top and bottom surfaces and generally planar side walls, with a clothoid shaped surface being formed on two corners of each paving-stone. The radius of curvature of each clothoid shaped surface may be different from that of the other clothoid shaped surfaces on each paving-stone. The top surface may have a different color and texture than the bottom surface. The paving-stones may be irregularly broken surfaces. | 4 |
PRIORITY
This application claims the benefit of U.S. Provisional Application No. 60/353,326 filed Feb. 1, 2002 and U.S. Des. Pat. No. D466,856 filed Feb. 1, 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a mounting device and system for use on all terrain vehicles.
2. Related Art
All terrain vehicles (“ATVs”) are used for a wide range of activities, including recreation, hunting, working and transportation. Many of these activities involve the use of auxiliary items, such as cameras, spotting scopes, umbrellas and warning flags. Because operation of the ATV generally requires the use of both hands of an operator, auxiliary items must be stored either on the ATV, or on the person of the operator and retrieved when desired. This is problematic for auxiliary items that an operator would like to be able to access very quickly, such as a spotting scope or a camera. Such items cannot be retrieved quickly because retrieval often requires the operator to dismount from the ATV to retrieve the item from its storage location.
An operator of an ATV who wishes to carry auxiliary items generally has a choice of storage options. The operator can store an item on the ATV, store the item on the person of the operator, or mount the item to the ATV. ATVs can be equipped with storage racks and bags for storing such items. Storage racks work well for larger items that can be secured to the storage rack with ropes or “bungee” chords, but do not work well for smaller items, which could fall through the racks while the ATV is in operation. Also, elongate items that are generally used in a vertical orientation, such as camera or scope mounts, can only be stored in the storage rack by laying the item horizontally on the rack. To be used, the items must be removed from the rack and elevated into a vertical position. Storing items in storage bags or on the person of the operator, such as in a backpack, is problematic in that an operator must open the bag or pack and remove the item before use.
An operator can also mount an auxiliary item directly to the ATV. For instance, warning flags, which often must be used in sand dune or hilly areas, are often mounted to the ATV. However, mounting such items is generally time consuming and often requires the use of one or more tools. Also, the items are generally removed from the ATV when no longer required, a step that again requires tools and consumes more time.
SUMMARY OF THE INVENTION
It has been recognized that it would be advantageous to develop a mounting device for use with ATVs that can be semi-permanently attached to an ATV, and thereafter allows an operator to quickly attach and detach auxiliary items to the device, and correspondingly, to the ATV.
The present invention provides an ATV quick-release mounting device with a mounting assembly which is attached to a member of the ATV. The mounting assembly is coupled to a receiving socket, to receive an adapter which may hold an auxiliary item. The receiving socket includes a maintaining means for maintaining of the adapter and to allow a user to quickly secure and release the adapter. The present invention can be semi-permanently attached to the ATV by the mounting assembly, and used thereafter to quickly and easily attach and remove auxiliary items to and from the ATV. Various auxiliary items may be secured such as firearms, spotting scopes, binoculars, monoculars, cameras, tools, and other view magnification devices.
In accordance with another aspect of the present invention, a mounting system for removably mounting auxiliary items includes an attachment assembly for attaching to a member of the ATV, and a receiving assembly with a socket. As part of the system, a plurality of adapters may be selectively and removably connected to the socket and to the auxiliary items. When needed an adapter having a particular auxiliary item attached thereto may be inserted into the socket and later removed in exchange for another adapter having an auxiliary item attached. The socket includes a maintaining means for quick-release maintaining of the adapter in the socket.
In accordance with a more detailed aspect of the present invention, the device includes a vertical riser to couple the receiving socket to the mounting assembly. The vertical riser can be threadably coupled or press-fit to the receiving socket and mounting assembly. The vertical riser can alternately be constructed as an integral piece that includes a mounting assembly component. The vertical riser can also be constructed as two or more pieces that telescopically extend and retract to adjust the height of the vertical riser.
In accordance with another, more detailed aspect of the present invention, the maintaining means can be configured as a bolt threaded through the wall of the receiving socket and configured to tighten against the adapter to secure the adapter to the mounting device. The maintaining means can also be configured as a tapered interior wall of the receiving socket to frictionally engage the adapter upon insertion into the receiving socket. The maintaining means can also be a pin extending through aligned openings in the receiving socket wall and the adapter. The pin can be a spring-ball type of pin or a threaded pin. The maintaining means can also be configured as a biasing element contained within the adapter and coupled to an engaging ball configured to engage openings in the sides of the adapter and the receiving socket. The maintaining means can also be more permanent in nature and can be configured as an adhesive, to bond the adapter to the receiving socket, a weld, or a press-fit.
In another more detailed aspect of the present invention, a mounting device is used to mount items to an all-terrain vehicle. The mounting device includes a mounting assembly connected to a member of the all-terrain vehicle and one end of a telescoping shank connected to the mounting assembly such that the length of the shank may be adjusted. At an opposite end of the shank is connected an attachment surface configured for securing an item thereon.
In yet another more detailed aspect of the present invention, the mounting device is designed for mounting hunting implements to an all-terrain vehicle. The hunting implement mounting device includes a mounting assembly having an attachment surface connected thereto which is capable of holding at least one hunting implement. A maintaining means is provided for maintaining the hunting implement on the all-terrain vehicle in a quick-release manner. Additionally, at least two hunting implements are provided which are interchangeable and releasably secured to the attachment surface.
In another detailed aspect of the present invention, the maintaining means may be located to provide quick-release of the attachment surface from the mounting assembly. In still another aspect of the present invention, the maintaining means may optionally, or in addition to the prior location, be located to provide quick-release of the mounting device from the all-terrain vehicle.
Finally, in another detailed aspect of the present invention, the mounting assembly and the attachment surface are substantially collinear to produce a substantially vertical mounting device which minimizes obstruction of neighboring areas.
There has thus been outlined, rather broadly, various features of the invention so that the detailed description thereof that follows may be better understood, and so that the present contribution to the art may be better appreciated. Other features of the present invention will become clearer from the following detailed description of the invention, taken with the accompanying claims, or may be learned by the practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side plan view of an ATV quick release mounting device in accordance with an embodiment of the present invention;
FIG. 2 a is a side plan view of an adapter of the present invention having a platform;
FIG. 2 b is a side plan view of an alternative adapter of the present invention having a platform;
FIG. 2 c is a side plan view of another alternative adapter of the present invention having a U-shaped holding member;
FIG. 3 a is a side plan view of an alternate embodiment of the present invention;
FIG. 3 b is a side plan, partial cutaway view of an alternate embodiment of the mounting assembly of the present invention;
FIG. 4 a is a side plan, partial cutaway view of an alternate embodiment of the receiving assembly of the present invention;
FIG. 4 b is a side plan view of one feature of an embodiment of the present invention;
FIG. 4 c is a side plan view of one feature of an embodiment of the present invention;
FIG. 5 is a side plan cutaway view of an alternate embodiment of the receiving assembly of the present invention; and
FIG. 6 is a perspective view of an alternative embodiment of the mounting device of the present invention.
DETAILED DESCRIPTION
Reference will now be made to the exemplary embodiments illustrated in the drawings, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Alterations and further modifications of the inventive features illustrated herein, and additional applications of the principles of the inventions as illustrated herein, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention.
As illustrated in FIG. 1 , a device, indicated generally at 10 , in accordance with the present invention is shown for an ATV mounting device. In accordance with one aspect of the present invention, the device 10 includes a receiving socket 12 configured to receive an adapter 14 . The receiving socket can include maintaining means, associated with the socket, for maintaining the adapter in the socket. In addition, the maintaining means can quickly secure the adapter to the receiving socket and subsequently quickly release the adapter for easy removal. Although the maintaining means is shown as a textured screw 16 , other configurations, such as wing-screws, thumb-screws, spring-ball interlock, or other quick-release mechanisms may be used. The maintaining means can also be configured as an adhesive, weld or press-fit securing devices to more permanently couple the adapter to the receiving socket. The device also includes a mounting assembly 18 configured to couple the mounting device to the ATV. The device can also include a vertical riser 20 to couple the receiving socket 12 to the mounting assembly 18 .
The adapter 14 may take a variety of configurations some of which are shown in FIGS. 2 a through 2 c . As shown in FIG. 2 a , the receivable end 60 of the adapter is designed to be removably disposable in the socket. The holding end 62 of the adapter 14 is designed based on the type of auxiliary item the user desires to mount to the ATV. FIG. 2 a shows an adapter having a platform surface 64 and a mounting screw 66 for removably attaching an auxiliary item, such as a camera or view magnification device having an appropriate threaded inset in which to thread the mounting screw. FIG. 2 b shows an adapter having a platform surface 64 and a threaded inset 68 for removably attaching an auxiliary item having a threaded member. FIG. 2 c shows an adapter having a holding end 62 having a generally U-shaped member for holding auxiliary items such as tools, firearms, bows, etc. Of course, some auxiliary items will require more than one mounting assembly to securely hold the auxiliary item. The holding end of the adapter may be of any configuration capable of holding an auxiliary item to the adapter and may include, without limitation, hook-and-loop type, clamps, straps, or combinations of these. Other possible configurations will occur to those using the present invention and desiring to secure various items to an ATV. Typically, the auxiliary items are mounted to an appropriate adapter and the items mounted as necessary.
Once mounted to the ATV, an operator of the ATV can use the device 10 to quickly secure or release an auxiliary item to the ATV. For example, the operator can use the device to quickly mount a camera support to the ATV to support a camera for use on the ATV. Once the camera support is mounted to the device, both of the operator's hands are free to operate the ATV, and the operator still has quick access to the camera. If the operator desires to photograph a subject, he or she could simply stop the ATV and quickly use the camera, without having to retrieve the camera from storage. The adapter could also be used to hold any of a number of auxiliary items commonly used by operators of ATVs, including a spotting scope mount, a gun rest, a warning flag, an umbrella, or a rack for holding other items. After being used for one purpose, the operator can disengage the quick-release mechanism of the current item being held and removably mount another item in very little time by engaging the maintaining means to hold the second adapter-auxiliary item combination. The quick-release mounting device of the present invention could also be used with any number of recreational vehicles, including ATVs, snowmobiles, motorcycles, bicycles, boats, jet skis, and tree-stands. The present discussion focuses on the use of the invention with an ATV as an exemplary embodiment, and it is to be understood that the invention is not thereby limited.
Referring again to FIG. 1 , the receiving socket 12 can be of any configuration but is preferably generally cylindrical in shape to receive a generally cylindrical receivable end 60 of an adapter 14 . A square or rectangular shaped receivable end or socket could also be used. The receiving socket is generally a hollow elongate socket having a closed end and an open end. Further, the closed end is attached to the mounting assembly via a connector, such as a riser assembly 20 , discussed in more detail below.
The mounting assembly can be of any configuration known to those skilled in the art. The embodiment illustrated in FIG. 1 includes a generally U-shaped bolt 22 which passes through a pair of openings or parallel holes in a rod member retaining bracket 23 . The retaining bracket includes a notch 25 which can rest on a member of the ATV (not shown). The ends 24 of the U-shaped bolt are threaded to accept retaining members 26 such as nuts which can be tightened to securely force the U-shaped bolt and notch against opposing sides of the member of the ATV to mount the quick release device to the ATV. The mounting assembly may be mounted at various positions on the ATV such as the handlebars, cargo racks or the ATV frame. Once the relatively time-consuming step of mounting the device to the ATV is complete, auxiliary items can be quickly and easily secured and removed from the ATV using the above-described adapters.
The mounting assembly 18 is not limited to the embodiment illustrated in FIG. 1 , but can also be configured in any manner known to those skilled in the art. Illustrated in FIG. 3 a is an alternate mounting assembly configuration. The vertical riser 20 can be coupled to one of a pair of chucks 32 . The chucks can include notches 39 which are configured to accept a member of the ATV at 38 to secure the quick release device to the ATV. Once positioned around the portion of the ATV, threaded bolts 34 are inserted through openings in the chucks. Nuts 36 can threadably engage the bolts and force the chucks into contact with the member of the ATV. The notch can be as shown, or can include serrated teeth to improve the frictional contact with the portion of the ATV or may be a concave indentation.
FIG. 3 b illustrates yet another alternative mounting assembly suitable for use in the present invention. This embodiment is particularly suited to ATV members having a rectangular cross-section. Two parallel plates 35 a and 35 b are placed on opposing sides of an ATV member 30 having a rectangular cross-section. Plate 35 a has the vertical riser 20 portion of the invention attached thereon. This vertical riser section may be a single solid piece or may be configured for variable adjustment of length as shown in FIG. 3 b . The plates are secured to the ATV member 30 using at least two transverse bolts 34 secured by nuts 36 . Although the mounting assemblies shown in FIGS. 1 , 3 a and 3 b are semi-permanent attachments other configurations are also considered within the scope of the present invention which are quick-release such as spring clamps, latched clamps or other known securing mounts.
As shown in FIG. 1 , the vertical riser 20 can be threaded to accept a nut 21 . The retaining bracket 23 can also be threaded to enable the vertical riser to threadably engage the retaining bracket. Once positioned in a desirable location, the nut can be tightened against the retaining bracket to control relative movement of the vertical riser and retaining bracket. Alternatively, the vertical riser can be press-fit into the retaining bracket, or coupled thereto in any manner known to those skilled it the art. The vertical riser and retaining bracket can alternately be formed of an integral piece. In this manner, the vertical riser can include openings for insertion of the ends 24 of the U-shaped bolt 22 . The vertical riser can similarly engage the receiving socket 12 in a variety of configurations, including a threaded connection, a press fit, or other known configuration. The vertical riser can also be formed of two or more pieces and thereby allow the operator to adjust the length of the vertical riser. As illustrated in FIG. 3 b , the vertical riser can include a locking mechanism 27 which can lock the relative positions of the upper 25 and lower 29 portions of the vertical riser. In this manner, the operator can release the locking mechanism and adjust the length of the vertical riser, thereby adjusting the height of the adapter 14 . Once a desirable length is obtained, the locking mechanism 27 can be engaged to fix the length of the vertical riser.
The maintaining means is shown in FIG. 1 as a threaded fastener 16 extending through the receiving socket 12 . In this manner, once the adapter 14 is inserted into the receiving socket 12 , the maintaining means can be tightened against the adapter to secure the adapter to the receiving socket. It will be appreciated that the maintaining means can be quickly engaged and disengaged to allow for quick interchange of auxiliary items.
The maintaining means for quick-release maintenance of the adapter is not limited to a threaded configuration. As illustrated by FIG. 3 a , the maintaining means 16 can be a tapered inside wall of the receiving socket configuration. In this embodiment, the adapter is simply inserted into the receiving socket until it engages the narrowing inside walls of the receiving socket. The adapter is held fast by the frictional contact between the adapter and the inside wall of the receiving socket. The auxiliary item can then be quickly removed and replaced, if desired, with another auxiliary item-adapter assembly. Although often preferred, the maintaining means is not limited to a quick connect configuration. The maintaining means can also be more permanent in nature, such as adhesive, weld or press-fit means.
An alternate embodiment of the maintaining means is illustrated in FIGS. 4 a through 4 c . The receiving socket 12 can include openings 40 which correspond to an opening 42 in the adapter 14 . Once the adapter is inserted into the receiving socket 12 , the openings 40 and 42 can be aligned and a pin 44 can be inserted through all three openings to secure the adapter to the receiving socket. The pin 44 shown in FIG. 4 a can be a conventional spring-ball loaded pin. When installed, the balls 45 are held outwardly by a biasing element inside the pin. When the release 47 is activated, the balls retract below the external surface of the pin and allow the pin to be withdrawn through the openings. FIGS. 4 a and 4 b illustrate alternate embodiments of the pin. The pin can be a threaded bolt 44 b which can threadably engage one of the openings 40 in the receiving socket to thereby secure the adapter. Alternately, the threaded bolt can pass through all openings 40 and 42 and be secured with a nut. As shown in FIG. 4 c , the pin could also be a simple rod 44 c which, once inserted into the openings, is held securely in place by the weight of the adapter 14 and auxiliary item. Also, a cotter pin could be inserted through the openings to secure the adapter to the receiving socket. The bolts and pins described above are further examples of maintaining means for quickly maintaining and securing the adapter to the receiving socket.
Another embodiment of the maintaining means is illustrated in FIG. 5 . In this embodiment, the maintaining means includes an engagement button or detent 50 which protrudes through an opening 51 in the wall of the receivable end 60 b of an adapter 14 b . The engagement button is biased against the wall of the adapter by a biasing element 52 within the receiving end 60 b of the adapter. Because the engagement button is larger than the opening 51 , only a portion of the button protrudes from the external wall of the adapter. As the adapter is inserted into the receiving socket 12 , the operator can depress the engagement button by applying a force at 55 . When the adapter is fully inserted into the receiving socket, the biasing member forces the engagement button into opening 53 in the wall of the receiving socket. The adapter is held securely in place by the engagement button. This embodiment of the maintaining means could be utilized with any adapter equipped with the biasing element and engagement button.
FIG. 6 illustrates yet another embodiment of the present invention wherein a mounting device is used to mount items to an ATV 69 . The mounting device includes a mounting assembly 18 connected to a member 63 of the all-terrain vehicle 69 . A telescoping shank 70 is connected to the mounting assembly 18 at one end. A rapid detaching member such as a locking nut 21 may be provided to releasably secure the shank to the mounting assembly. The length of the shank may be adjusted using locking mechanism 27 . The opposite end of the shank is connected an attachment surface 62 configured for securing an item 65 thereon. A monocular is shown in FIG. 6 although any number of items could be secured to the attachment surface such as, but not limited to, firearms, spotting scopes, binoculars, cameras, tools, view magnification devices, hunting implements and the like. The mounting surface 62 may include a secondary surface which may be easily detachable from the mounting surface to increase the ease with which various items may be interchanged on the mounting device.
In yet another more detailed aspect of the present invention, the mounting device is designed for mounting hunting implements to an all-terrain vehicle. The hunting implement mounting device includes a mounting assembly having an attachment surface connected thereto which is capable of holding at least one hunting implement. A maintaining means is provided for maintaining the hunting implement on the all-terrain vehicle in a quick-release manner as discussed above. Additionally, at least two hunting implements are provided which are interchangeable and releasably secured to the attachment surface.
Various hunting implements may be secured to the ATV using the device of the present invention including, but not limited to, firearms, bows, spotting scopes, binoculars, fishing rods, nets, and cameras. Additionally, various holding members may be secured to the attachment surface 62 which hold the hunting implement such as a rifle rest having a base.
In another detailed aspect of the present invention, the maintaining means may be located to provide quick-release of the attachment surface from the mounting assembly in the same manner as discussed above. In still another aspect of the present invention, the maintaining means may optionally, or in addition to the prior location, be located to provide quick-release of the mounting device from the ATV such as with a spring clamp or latching clamp.
Finally, in another detailed aspect of the present invention, the mounting assembly 18 and the attachment surfaces 62 are substantially collinear to produce a substantially vertical mounting device which minimizes obstruction of neighboring areas. This configuration is advantageous in several respects. For example, when the mounting device is secured to either the front or rear cargo racks of the ATV the vertical orientation will reduce interference with full use of the cargo area for other items. Additionally, the vertical orientation of the present invention will improve driving visibility when secured to the front of the ATV.
It is to be understood that the above-referenced arrangements are only illustrative of the application for the principles of the present invention. Numerous modifications and alternative arrangements can be devised without departing from the spirit and scope of the present invention while the present invention has been shown in the drawings and fully described above with particularity and detail in connection with what is presently deemed to be the most practical and preferred embodiments of the invention, it will be apparent to those of ordinary skill in the art that numerous modifications can be made without departing from the principles and concepts of the invention as set forth herein. | A mounting device for use with ATVs that can be semi-permanently attached to an ATV to allow an operator to attach and detach auxiliary items to the device, and correspondingly, to the ATV. The device includes a receiving socket to temporarily receive an adapter, the receiving socket including a maintaining means for maintaining the adapter in the socket and allow the user to quickly secure and release the adapter, and a mounting assembly, coupled to the upper receiving socket and configured to be attached to the ATV. Using a plurality of adapters, each having an auxiliary item attached, provides a mounting system for quickly interchanging auxiliary items and securing them to the ATV with minimum effort. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase Application of PCT International Application Number PCT/EP2014/055815, filed on Mar. 24, 2014, designating the United States of America and published in the English language, which is an International Application of and claims the benefit of priority to European Patent Application No. 13160829.1, filed on Mar. 25, 2013. The disclosures of the above-referenced applications are hereby expressly incorporated by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates to new and improved processes for the preparation of Alcaftadine and pharmaceutically acceptable salts thereof as well as an intermediate for the preparation of Alcaftadine.
BACKGROUND OF THE INVENTION
The compound 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]benzazepine-3-carboxaldehyde, which is known as Alcaftadine (INN), and its corresponding salts are H1 histamine receptor antagonists indicated for the prevention of itching associated with allergic conjunctivitis and is sold commercially as an ophthalmic solution containing Alcaftadine (0.25%) under the trade name Lastacaft.
EP 0 588 858 describes the preparation of Alcaftadine for the first time through the process:
It is evident that a number of steps are needed in EP 0 588 858 to arrive at the intermediate of formula 7 (free base) from the starting compound of formula 1 with a relatively low yield. Furthermore, the introduction in the intermediate of formula 7 (free base) of the hydroxymethyl substituent and subsequent oxidation to arrive at Alcaftadine requires a cumbersome, low-yield protection and de-protection process, using an ethylcarboxylate protecting group.
In addition, the introduction of the hydroxymethyl group requires stirring with 22 equivalents of formaldehyde for at least 1 week according to example 20a) of EP 0 588 858. Long reaction times furthermore increase the risk of obtaining the dihydroxymethyl impurity (example 20b)).
There exists, therefore, the need to develop an improved process for obtaining Alcaftadine and salts thereof, which overcomes some or all of the problems associated with known methods from the state of the art. More particularly, there exists the need for a process for obtaining Alcaftadine and pharmaceutically acceptable salts thereof, which results in a higher yield and/or having fewer reaction steps.
SUMMARY OF THE INVENTION
In one aspect of the invention, it concerns a process for preparing Alcaftadine or a pharmaceutically acceptable salt thereof reacting the acid addition salt of formula 7 with formaldehyde to the compound of formula 11 or a salt thereof and then oxidizing the compound of formula 11 or a salt thereof to Alcaftadine:
and optionally converting Alcaftadine to a pharmaceutically acceptable salt thereof,
wherein the acid addition salt of formula 7 is a salt formed with a di-carboxylic acid, HA, such as fumaric acid, maleic acid, succinic acid, or tartaric acid.
This process converts the acid addition salt of formula 7 directly to the compound of formula 11 without the need for protecting with ethyl carboxylate and therefore saves three reaction steps. Furthermore, the yield is significantly increased and the reaction time for introducing the hydroxymethyl group has been reduced to less than two days. This, in turn, decreases the risk of introducing a second hydroxymethyl group into the compound in a quantitative amount.
A further aspect of the invention concerns a process for the preparation of Alcaftadine or a pharmaceutically acceptable salt thereof comprising reacting a compound of formula 1 with ethyl 1-methylpiperidine-4-carboxylate in the presence of a strong base to provide a compound of formula 4, which is further reacted with trifluoromethanesulfonic acid and subsequently a di-carboxylic acid, HA, as defined above to provide the acid addition salt of formula 7:
and further reacting the acid addition salt of formula 7 to provide Alcaftadine or, optionally, a pharmaceutically acceptable salt thereof.
The method herein provides Alcaftadine in a yield and purity superior to the methods known in the art. Furthermore, it has been found that careful selection of crystallization solvents will provide Alcaftadine in a purity higher than 99%. Hence, yet a further aspect of the invention concerns a process for the isolation and purification of Alcaftadine comprising crystallization in isopropyl alcohol or ethyl acetate.
In another aspect of the invention, it concerns an acid addition salt of formula 7:
wherein the di-carboxylic acid, HA, is as defined above.
The neutral form of the acid addition salt of formula 7 is known from EP 0 588 858, but the acid addition salt of formula 7 is a novel compound.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
In the present context, the term “strong base” is intended to mean a base sufficiently strong to remove a hydrogen from position 2 of the imidazole ring in the compound of formula 1. Such bases are well known to the person skilled in the art and include inter alia lithium diisopropylamide, hexyl-lithium, butyl-lithium, and lithium hexamethyldisilazide.
In the present context, when referring to “the acid addition salt of formula 7”, “compound of formula 7” or “intermediate 7”, it is intended to mean the acid addition salt and not the free base, unless explicitly referred to as the free base or the context otherwise makes it clear that the free base is meant.
In the present context, the term “di-carboxylic acid” is intended to mean an organic acid with two or more carboxylic acid groups and a total of 2 to 10 carbon atoms in the molecule. Thus, the term “di-carboxylic acid” includes, by way of example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, tartaric acid, EDTA, citric acid, fumaric acid, maleic acid, glutaconic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid, and malic acid.
Processes
In one aspect of the invention, it concerns a process for preparing Alcaftadine or a pharmaceutically acceptable salt thereof reacting the acid addition salt of formula 7 with formaldehyde, optionally in the presence of a base, to the compound of formula 11 or a salt thereof and then oxidizing the compound of formula 11 or a salt thereof to Alcaftadine:
and optionally converting Alcaftadine to a pharmaceutically acceptable salt thereof,
wherein the acid addition salt of formula 7 is a salt formed with a di-carboxylic acid, HA, such as fumaric acid, maleic acid, succinic acid, or tartaric acid.
In one embodiment, the acid addition salt of formula 7 is formed by reacting the compound of formula 1 with ethyl 1-methylpiperidine-4-carboxylate in the presence of a strong base to provide a compound of formula 4, which is further reacted with trifluoromethanesulfonic acid and subsequently a di-carboxylic acid, HA, as defined above to provide the acid addition salt of formula 7:
In a further embodiment, said strong base is lithium diisopropylamide or hexyl lithium.
A further aspect of the invention concerns a process for the preparation of Alcaftadine or a pharmaceutically acceptable salt thereof comprising reacting a compound of formula 1 with ethyl 1-methylpiperidine-4-carboxylate in the presence of a strong base to provide a compound of formula 4, which is further reacted with trifluoromethanesulfonic acid and subsequently a di-carboxylic acid, HA, as defined above to provide the acid addition salt of formula 7:
and further reacting the acid addition salt of formula 7 to provide Alcaftadine or, optionally, a pharmaceutically acceptable salt thereof.
In one embodiment, said strong base is lithium diisopropylamide or hexyl lithium.
Yet a further aspect of the invention concerns a process for the isolation and purification of Alcaftadine comprising crystallization in isopropyl alcohol or ethyl acetate.
In another aspect of the invention, it concerns an acid addition salt of formula 7:
wherein the di-carboxylic acid, HA, is as defined above.
The Di-Carboxylic Acid
The di-carboxylic acid serves a double function in that it both facilitates the purification of the acid addition salt of formula 7 by crystallization and at the same time provides a much better starting point for introducing the hydroxymethyl group into the molecule than the corresponding neutral compound. The corresponding reaction from the corresponding neutral base to the compound of formula 11 lasts at least 1 week, whereas taking the acid addition salt of formula 7 as the starting point means that the reaction only needs about 20 to 40 hours to complete.
The di-carboxylic acid may in one embodiment be selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, tartaric acid, EDTA, citric acid, fumaric acid, maleic acid, glutaconic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid, and malic acid. In another embodiment, said di-carboxylic acid is selected from the group consisting of fumaric acid, maleic acid, succinic acid, and tartaric acid. In a further embodiment, said di-carboxylic acid is fumaric acid or succinic acid. In yet a further embodiment, said di-carboxylic acid is fumaric acid. In still a further embodiment, said di-carboxylic acid is succinic acid.
Oxidation Reagents
The skilled person is familiar with the oxidation reagents used in the art for selectively oxidizing primary alcohols to the corresponding aldehyde. These oxidation reagents include chromium-based reagents, such as Collins reagent (CrO 3 .Py 2 ), pyridinium dichromate, or pyridinium chlorochromate; activated DMSO, resulting from reaction of DMSO with electrophiles, such as oxalyl chloride (Swern oxidation), a carbodiimide (Pfitzner-Moffatt oxidation) or the complex SO 3 .Py (Parikh-Doering oxidation); hypervalent iodine compounds, such as Dess-Martin periodinane or 2-Iodoxybenzoic acid; catalytic tetrapropylammonium perruthenate in the presence of excess of N-methylmorpholine N-oxide (Ley oxidation); catalytic TEMPO in the presence of excess sodium hypochlorite (Anelli's oxidation); or manganese dioxide.
In one embodiment, the oxidation reagent in the reaction from the compound of formula 11 to the compound of formula 12 (Alcaftadine) is manganese dioxide, MnO 2 .
The Reaction Forming the Compound of Formula 4
The starting compounds, the compound of formula 1 (CAS number 49823-14-5) and 1-methylpiperidine-4-carboxylate (CAS number 24252-37-7), are commercially available.
The reaction between the compound of formula 1 and 1-methylpiperidine-4-carboxylate is carried out in the presence of a strong base, as defined above. The bases meeting this definition are well known to the skilled person and include hexyl-lithium, butyl-lithium, lithium hexamethyldisilazide, and sodium hydride. In one embodiment, said strong base is lithium diisopropylamide.
The reaction temperature is advantageously kept in the range −80° C. to −30° C., such as in the range −80° C. to −40° C., e.g. in the range −80° C. to −60° C.
In order to avoid build-up of impurities during the reaction, it is advantageous to add between 1 and 3 equivalents of 1-methylpiperidine-4-carboxylate, such as between 1.5 and 2.6 equivalents. Hence, in one embodiment 1 to 3 equivalents of 1-methylpiperidine-4-carboxylate are added to the compound of formula 1. In another embodiment, 1.5 to 2.6 equivalents of 1-methylpiperidine-4-carboxylate are added to the compound of formula 1.
The reaction solvent used is advantageously an aprotic solvent. In one embodiment, the solvent is tetrahydrofuran, toluene, or a mixture thereof.
The resulting product, the compound of formula 4, may be isolated in acetone, ethyl acetate, or dichloromethane in the form of the hydrochloride or the hydrobromide.
The overall yield of the reaction is up to 85%.
The Reaction Forming the Acid Addition Salt of Formula 7
The ring closure of the compound of formula 4 may be achieved by adding trifluoromethanesulfonic acid as the only acid component. Advantageously, the reaction is carried out at a temperature between 70 and 130° C. using 4 to 20 volumes of trifluoromethanesulfonic acid. Hence, in one embodiment, the reaction is carried out at a temperature between 70 and 130° C., such as a temperature between 90 and 130° C., e.g. between 110 and 130° C. In another embodiment, the reaction is carried out using between 4 and 20 volumes of trifluoromethanesulfonic acid, such as between 10 and 20 volumes, e.g. between 15 and 20 volumes.
The resulting product may be purified by crystallization by adding the di-carboxylic acid, HA, to form the acid addition salt of formula 7. Suitable solvents for the crystallization include acetone, methanol, ethyl acetate, isopropyl alcohol, and mixtures thereof. In one embodiment, said solvent for the crystallization of the acid addition salt of formula 7 is selected from acetone, isopropyl alcohol, and mixtures thereof.
The Reaction Forming the Compound of Formula 11
The acid addition salt of formula 7 may be used as the starting point in purified or non-purified form. In both cases, the reaction time is reduced considerably compared to taking the corresponding neutral base as the starting point, even if the neutral compound is in purified form.
The reaction between the acid addition salt of formula 7 and formaldehyde is advantageously carried out with heating, such as at a temperature between 80 and 100° C., in an aqueous solvent or in combination with an organic solvent such as Toluene, Xylene or heptane.
Furthermore, the reaction between the acid addition salt of formula 7 and formaldehyde is advantageously carried out in the presence of a base. However, the reaction carried out without the presence of a base is still considerably more efficient than the corresponding reaction carried out with the neutral form of the acid addition salt of formula 7 (comparative example 12). In one embodiment, said base is selected from the group consisting of carboxylate, such as acetate; carbonate or bicarbonate; pyridine; and benzyltrimethylammonium hydroxide. In a further embodiment, said base is a carboxylate or bicarbonate. In yet a further embodiment, said base is acetate. In yet a further embodiment, said base is sodium acetate. In still a further embodiment, said base is sodium acetate, sodium bicarbonate or pyridine.
The overall yield of the reaction is 70-75%. The yield and purity of the direct product of the reaction, the compound of formula 11, facilitates its purification on an industrial scale, such as by crystallization of the fumarate salt in acetone as solvent or by crystallization of the succinate salt in Ethyl acetate as solvent. Acetonitrile is a suitable solvent for the crystallization of the compound of formula 11 as a base.
The Oxidation of the Compound of Formula 11
The reaction conditions for the oxidation reaction may depend on the chosen oxidation reagent. In the case of manganese dioxide, the reaction may be carried out under similar circumstances as those disclosed in EP 0 588 858 (example 51).
Purification of Alcaftadine
The product (Alcaftadine) may be isolated and purified from solvents such as isopropanol, ethyl acetate, or isopropyl ether. Isopropanol and ethyl acetate may advantageously be used as solvents for the purification with a final yield of 50-65%.
Hence, yet a further aspect of the invention concerns a process for the isolation and purification of Alcaftadine comprising crystallization in isopropyl alcohol or ethyl acetate.
Pharmaceutically Acceptable Salts
Pharmaceutically acceptable acid addition salts of Alcaftadine are easily identified by the skilled person. A useful list of pharmaceutically acceptable acid addition salts may be found in Berge et al: “Pharmaceutical Salts”, Journal of Pharmaceutical Sciences, vol. 66, no. 1, 1 Jan. 1977, pages 1-19.
Intermediate Compounds
The process of the invention involves a novel intermediate, which has not previously been used in the preparation of Alcaftadine. Hence, a further aspect of the invention concerns the acid addition salt of formula 7.
EXAMPLES
Example 1
Preparation of [1-(2-phenylethyl)-1H-imidazol-2-yl](1-methyl-4-piperidinyl)-methanone (intermediate 4)
N-(2-phenyl)-ethyl imidazole (20 g, 0.12 mol) was dissolved in a mixture of toluene (100 ml) and tetrahydrofuran (60 ml). The solution formed was cooled down to −50° C. and then a solution of LDA (lithium diisopropylamide) 2 M in tetrahydrofuran (128 ml, 0.26 mol) was added. The temperature was kept at −50° C. for 15 minutes and then a solution of N-methyl ethyl isonipecotate (48.1 g, 0.28 mol) in toluene (50 ml) was added. After 1 hour at −50° C. the reaction was quenched by addition of water (200 ml).
The temperature was adjusted to 20° C. and the layers were separated. The aqueous layer was extracted with toluene and the solvents were distilled to a final volume of 60 ml.
A 5-6 N solution of HCl in isopropanol (74 ml) was added followed by acetone 1200 ml. The solid formed was filtered, washed with acetone (100 ml) and dried to afford 28.5 g (74% yield) of [1-(2-phenylethyl)-1H-imidazol-2-yl](1-methyl-4-piperidinyl)-methanone (intermediate 4) as the hydrochloride salt.
Spectroscopic Data of Intermediate 4 (Hydrochloride Salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 1.80-2.00 (4H, m), 2.67 (3H, d, J=4.8 Hz), 2.95 (2H, t, J=7.2 Hz), 2.95-3.10 (2H, m), 3.39 (2H, d, J=11.2 Hz), 3.70-3.80 (1H, m), 4.56 (2H, t, J=7.2 Hz), 7.13 (1H, s), 7.15-7.25 (5H, m), 7.50 (1H, s), 11.0 (1H, broad s).
13 C-NMR (100 MHz, DMSO-d6), δ: 25.4 (2×CH 2 ), 36.7 (CH 2 ), 41.0 (CH), 42.5 (CH 3 ), 49.0 (CH 2 ), 52.3 (2×CH 2 ), 126.5 (CH), 127.6 (CH), 128.4 (2×CH), 128.7 (2×CH), 137.6 (C), 137.7 (C), 140.3 (C), 191.9 (C═O)
A sample of the solid (1 g) was dissolved in dichloromethane and water and the pH was adjusted to 9-10 with 50% aqueous NaOH. The product was extracted with dichloromethane and the solvent was distilled off to afford 0.85 g of [1-(2-phenylethyl)-1H-imidazol-2-yl](1-methyl-4-piperidinyl)-methanone (intermediate 4) (free base) as a colourless oil.
Spectroscopic Data of Intermediate 4 (Free Base):
1 H-NMR (400 MHz, DMSO-d6), δ: 1.56 (2H, dq, J=3.6, 12.4 Hz), 1.71 (1H, d, J=12.0 Hz), 1.87 (1H, t, J=11.2 Hz), 2.11 (3H, s), 2.75 (1H, d, J=11.2 Hz), 2.94 (2H, t, J=7.2 Hz), 3.50 (1H, tt, J=3.6, 12.0 Hz), 4.55 (2H, t, J=7.2 Hz), 7.04 (1H, s), 7.10-7.25 (5H, m), 7.36 (1H, s).
13 C-NMR (100 MHz, DMSO-d6), δ: 28.1 (2×CH 2 ), 36.8 (CH 2 ), 43.3 (CH), 46.1 (CH 3 ), 48.9 (CH 2 ), 54.8 (2×CH 2 ), 126.3 (CH), 126.9 (CH), 128.2 (2×CH), 128.6 (2×CH), 137.7 (C), 141.1 (C), 194.3 (C═O).
Example 2
Preparation of [1-(2-phenylethyl)-1H-imidazol-2-yl](1-methyl-4-piperidinyl)-methanone (intermediate 4) as the hydrobromide salt
N-(2-phenyl)-ethyl imidazole (7.9 g, 0.046 mol) was dissolved in a mixture of toluene (40 ml) and tetrahydrofuran (24 ml). The solution formed was cooled down to −50° C. and then a solution of hexyllithium 2.7 M in hexane (37.5 ml, 0.101 mol) was added. The temperature was kept at −50° C. for 15 minutes and then a solution of N-methyl ethyl isonipecotate (19.0 g, 0.11 mol) in toluene (20 ml) was added. After 1 hour at −50° C. the reaction was quenched by addition of water (80 ml).
The temperature was adjusted to 20° C. and the layers were separated. The aqueous layer was extracted with toluene and the solvents were distilled to a final volume of 24 ml.
A 33% solution of HBr in acetic acid (7.8 ml) was added followed by ethyl acetate (160 ml). The solid was filtered, washed with ethyl acetate (40 ml) and dried to afford 11.6 g (67% yield) of intermediate 4 as the hydrobromide salt. Spectroscopic data of intermediate 4 (hydrobromide salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 1.80 (2H, m, J=12.4 Hz), 1.98 (2H, d, J=12.0 Hz), 2.75 (3H, d, J=4.8 Hz), 2.95 (2H, t, J=7.2 Hz), 3.08 (2H, qd, J=3.8, 12.0 Hz), 3.46 (2H, d, J=12.0 Hz), 3.75 (1H, tt, J=3.2, 12.0 Hz), 4.57 (2H, t, J=7.6 Hz), 7.11 (2H, d, J=7.2 Hz), 7.15 (1H, s), 7.15-7.30 (3H, m), 7.54 (1H, s), 9.57 (1H, broad s).
13 C-NMR (100 MHz, DMSO-d6), δ: 25.2 (2×CH 2 ), 36.6 (CH 2 ), 40.9 (CH), 42.6 (CH 3 ), 49.0 (CH 2 ), 52.5 (2×CH 2 ), 126.5 (CH), 127.6 (CH) 128.2 (CH), 128.4 (2×CH), 128.7 (2×CH), 128.8 (C), 137.6 (C), 140.1 (C), 191.6 (C═O).
Example 3
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt (Intermediate 7)
A mixture of trifluoromethanesulfonic acid (600 ml) and intermediate 4.HCl (74 g of hydrochloride salt, 0.22 mol) was heated to 95° C. for 6 hours. When the reaction was complete, the solution was cooled to 25° C. and poured into 1.5 L of cold (0/5° C.) water. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone and the volume was adjusted to 590 ml. Fumaric acid (25.7 g, 0.22 mol) was added and the mixture warmed to 50/55° C. for 1 hour. The solvent was distilled to a final volume of 295 ml. The suspension was cooled to 20° C., filtered and washed with cold acetone. After drying 60.5 g (69% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 7, fumarate salt) were obtained.
Spectroscopic Data of Intermediate 7 (Fumarate Salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 2.25-2.35 (1H, m), 2.49 (3H, s, CH 3 ), 2.45-2.55 (1H, m), 2.67 (1H, t, J=8.4 Hz), 2.75-2.85 (1H, m), 2.85-3.10 (5H, m), 3.39 (1H, td, J=3.6, 14.0 Hz), 3.91 (1H, t, J=12.8 Hz), 4.36 (1H, d, J=12.8 Hz), 6.53 (2H, s, 2×CH fumaric acid), 6.90 (1H, s), 7.02 (1H, s), 7.09 (1H, d, J=6.8 Hz), 7.23 (2H, quint, J=7.2 Hz), 7.34 (1H, d, J=6.8 Hz), 10.4 (3H, broad s, 2×COOH+NH).
13 C-NMR (100 MHz, DMSO-d6), δ: 28.6 (CH 2 ), 28.7 (CH 2 ), 30.3 (CH 2 ), 43.1 (CH 3 ), 48.3 (CH 2 ), 54.2 (CH 2 ), 54.4 (CH 2 ), 121.2 (CH), 125.5 (C), 126.6 (CH), 127.1 (CH), 127.9 (CH), 128.4 (CH), 128.6 (CH), 134.8 (2×CH, fumaric acid), 136.8 (C), 137.1 (C), 139.1 (C), 142.6 (C), 167.6 (2×COO).
Example 4
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt (intermediate 7)
A mixture of trifluoromethanesulfonic acid (150 ml) and intermediate 4.HBr (14.5 g of hydrobromide salt, 0.04 mol) was heated to 105° C. for 6 hours. When the reaction was complete the solution was cooled to 25° C. and poured into water (450 ml) at 0/5° C. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone and the volume was adjusted to 110 ml. Fumaric acid (4.4 g, 0.04 mol) was added and the mixture warmed to 50/55° C. for 1 hour. The suspension was cooled to 0° C., filtered and washed with cold acetone. After drying 9.9 g (65% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 7, fumarate salt) were obtained.
Example 5
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt (intermediate 7)
Intermediate 4 (3.53 g of hydrochloride salt or 4.0 g of hydrobromide salt, 0.011 mol) was dissolved in water (20 ml) and dichloromethane (20 ml). The pH was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled off and to the resulting oil, trifluoromethanesulfonic acid (30 ml) was added and the reaction heated to 105° C. for 6 hours. The solution was cooled to 25° C. and poured into into water (30 ml) at 0/5° C. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled off and changed to acetone and the volume was adjusted to 110 ml. Fumaric acid (1.2 g, 0.011 mol) was added and the mixture warmed to 50/55° C. for 1 hour. The suspension was cooled to 0° C., filtered and washed with cold acetone. After drying 2.5 g (58% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 7, fumarate salt) were obtained.
Intermediate 7 was also isolated, after reaction according to the previous examples, as:
Free base: The final organic phase was distilled off and the solvent changed to ethyl acetate/heptanes. The product was isolated by filtration.
Spectroscopic Data of Intermediate 7 (Free Base):
1 H-NMR (400 MHz, DMSO-d6), δ: 1.98 (1H, td, J=3.2, 9.6 Hz), 2.05-2.20 (2H, m), 2.11 (3H, s, CH 3 ), 2.29 (1H, ddd, J=5.2, 9.2, 13.6 Hz), 2.45-2.55 (1H, m), 2.55-2.75 (3H, m), 2.92 (1H, dt, J=3.2, 13.6 Hz), 3.33 (1H, td, J=4.0, 13.6 Hz), 3.89 (1H, td, J=3.2, 13.6 Hz), 4.35 (1H, dt, J=4.0, 13.6 Hz), 6.85 (1H, s), 6.97 (1H, s), 7.05 (1H, d, J=6.8 Hz), 7.15-7.25 (2H, m), 7.32 (1H, d, J=6.8 Hz).
13 C-NMR (100 MHz, DMSO-d6), δ: 30.4 (CH 2 ), 30.7 (CH 2 ), 30.8 (CH 2 ), 45.6 (CH 3 ), 48.2 (CH 2 ), 56.4 (CH 2 ), 56.5 (CH 2 ), 120.8 (CH), 124.0 (C), 126.4 (CH), 127.0 (CH), 127.5 (CH), 128.4 (CH), 128.5 (CH), 137.0 (C), 139.7 (C), 140.5 (C), 143.1 (C).
Succinate salt: The final organic phase was distilled off and the solvent changed to acetone or ethyl acetate. Succinic acid (1 mol eq.) was added, the suspension was stirred and the product isolated by filtration.
Spectroscopic Data of Intermediate 7 (Succinate Salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 2.15-2.25 (1H, m), 2.30 (3H, s, CH 3 ), 2.25-2.45 (3H, m), 2.37 (4H, s, succinic acid), 2.70-2.85 (4H, m), 2.93 (1H, d, J=14.0 Hz), 3.36 (1H, td, J=4.0, 14.0 Hz), 3.90 (1H, td, J=2.8, 12.8 Hz), 4.36 (1H, d, J=12.0 Hz), 6.53 (2H, s, 2×CH fumaric acid), 6.89 (1H, s), 7.00 (1H, s), 7.07 (1H, d, J=6.4 Hz), 7.15-7.25 (2H, m), 7.33 (1H, d, J=6.4 Hz), 9.1 (3H, broad s, 2×COOH+NH).
13 C-NMR (100 MHz, DMSO-d6), δ: 29.5 (CH 2 ), 29.6 (2×CH 2 , succinic acid), 29.7 (CH 2 ), 30.4 (CH 2 ), 44.4 (CH 3 ), 48.3 (CH 2 ), 55.3 (CH 2 ), 55.5 (CH 2 ), 121.1 (CH), 124.7 (C), 126.6 (CH), 127.0 (CH), 127.7 (CH), 128.5 (CH), 128.6 (CH), 137.1 (C), 138.6 (C), 139.4 (C), 142.8 (C), 174.2 (2×COO).
Maleate salt: The final organic phase was distilled off and the solvent changed to acetone. Maleic acid (1 mol eq.) was added, the suspension was stirred and the product isolated by filtration.
Spectroscopic Data of Intermediate 7 (Maleate Salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 2.35-2.60 (2H, m), 2.47 (3H, s, CH 3 ), 2.77 (2H, 2), 3.01 (1H, d, J=14.0 Hz), 3.25-3.55 (4H, m), 4.02 (1H, td, J=3.2, 12.8 Hz), 4.45 (1H, d, J=13.2 Hz), 6.07 (2H, s, 2×CH maleic acid), 7.14 (1H, d, J=6.8 Hz), 7.26 (1H, s), 7.28 (1H, s), 7.25-7.35 (2H, m), 7.40 (1H, d, J=6.8 Hz).
13 C-NMR (100 MHz, DMSO-d6), δ: 27.7 (CH 2 ), 27.9 (CH 2 ), 30.0 (CH 2 ), 42.3 (CH 3 ), 48.8 (CH 2 ), 53.2 (CH 2 ), 53.5 (CH 2 ), 122.5 (CH), 127.0 (C), 128.3 (CH), 128.6 (CH), 128.9 (CH), 134.5 (2×CH, maleic acid), 137.0 (C), 138.4 (C), 139.7 (C), 141.9 (C), 167.1 (2×COO).
Tartrate salt: The final organic phase was distilled off and the solvent changed to acetone. Tartaric acid (1 mol eq.) was added, the suspension was stirred and the product isolated by filtration.
Spectroscopic Data of Intermediate 7 (Tartrate Salt):
1 H-NMR (400 MHz, DMSO-d6), δ: 2.25-2.35 (1H, m), 2.47 (3H, s, CH 3 ), 2.50-2.60 (1H, m), 2.64 (2H, s), 2.80-3.05 (3H, m), 3.10-3.20 (2H, m), 3.41 (1H, td, J=3.6, 14.0 Hz), 3.92 (1H, td, J=3.2, 12.8 Hz), 4.19 (2H, s, tartaric acid), 4.37 (1H, d, J=12.8 Hz), 6.82 (5H, broad s, 2×COOH+2×OH+NH), 6.92 (1H, s), 7.05 (1H, s), 7.10 (1H, d, J=7.2 Hz), 7.24 (2H, quint, J=7.2 Hz), 7.35 (1H, d, J=7.2 Hz).
13 C-NMR (100 MHz, DMSO-d6), δ: 28.0 (CH 2 ), 30.3 (CH 2 ), 30.8 (CH 2 ), 42.6 (CH 3 ), 48.4 (CH 2 ), 53.8 (CH 2 ), 54.0 (CH 2 ), 72.2 (2×CH, tartaric acid), 121.5 (CH), 125.8 (C), 126.8 (CH), 126.9 (CH), 128.1 (CH), 128.4 (CH), 128.7 (CH), 135.7 (C), 137.8 (C), 138.9 (C), 142.4 (C), 173.9 (2×COO).
Example 6
A mixture of trifluoromethanesulfonic acid (160 ml) and intermediate 4.HCl (20 g of hydrochloride salt, 0.06 mol) was heated to 95° C. for 6 hours. When the reaction was complete, the solution was cooled to 25° C. and poured into 400 ml of cold (0/5° C.) water. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone and the volume was adjusted to 60 ml. Succinic acid (17.0 g, 0.14 mol) was added and the mixture warmed to 50/55° C. for 1 hour. The suspension was cooled to 0° C., filtered and washed with cold acetone. After drying 22.0 g (71% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H imidazo[2,1-b][3]-benzazepine (intermediate 7, succinate salt) were obtained.
Example 7
A mixture of trifluoromethanesulfonic acid (80 ml) and intermediate 4.HCl (10 g of hydrochloride salt, 0.03 mol) was heated to 95° C. for 6 hours. When the reaction was complete, the solution was cooled to 25° C. and poured into 200 ml of cold (0/5° C.) water. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone and the volume was adjusted to 60 ml. Isopropanol (7 ml) and succinic acid (8.5 g, 0.07 mol) were added and the mixture warmed to 50/55° C. for 1 hour. The suspension was cooled to 0° C., filtered and washed with cold acetone. After drying 9.5 g (61% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H imidazo[2,1-b][3]-benzazepine (intermediate 7, succinate salt) were obtained.
Example 8
A mixture of trifluoromethanesulfonic acid (40 ml) and intermediate 4.HCl (5.0 g of hydrochloride salt, 0.015 mol) was heated to 95° C. for 6 hours. When the reaction was complete, the solution was cooled to 25° C. and poured into 100 ml of cold (0/5° C.) water. The pH was adjusted to 9/10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone and the volume was adjusted to 60 ml. Methanol (2.5 ml) and succinic acid (4.3 g, 0.036 mol) were added and the mixture warmed to 50/55° C. for 1 hour. The suspension was cooled to 0° C., filtered and washed with cold acetone. After drying 3.2 g (41% yield) of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H imidazo[2,1-b][3]-benzazepine (intermediate 7, succinate salt) were obtained.
Example 9
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt in the presence of sodium acetate (Intermediate 11.fumarate)
A mixture of intermediate 7 (5.0 g of the fumarate salt, 0.013 mol), 40% aqueous formaldehyde (22.5 ml) and sodium acetate (1.5 g, 0.02 mol) was heated to 95° C. for 20 hours. After this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 70%), intermediate 7 (ca 15%) and 2,3-dihydroxymethyl impurity: 6,11-dihydro-2,3-dihydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (ca 15%).
The reaction was cooled to 20° C., the pH was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone to a final volume of 40 ml. Fumaric acid (1.5 g, 0.013 mol) was added and the mixture heated to reflux for 1 hour. The suspension was cooled to 0° C., filtered and washed to afford a solid (4.7 g 85% yield) consisting of a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 70%), intermediate 7 (ca 15%) and the 2,3-dihydroxymethyl impurity: 6,11-dihydro-2,3-dihydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (ca 15%).
Example 10
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt in the presence of sodium acetate (Intermediate 11.fumarate)
A mixture of intermediate 7 (138 g of the fumarate salt, 0.32 mol), xylene (270 ml) 40% aqueous formaldehyde (540 ml) and sodium acetate trihydrate (59.5 g) was heated to 95° C. for 20 hours. After this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 70%), intermediate 7 (ca 15%) and the 2,3-dihydroxymethyl impurity (ca 15%).
The reaction was cooled to 20° C., and the two phases were separated. The pH of the aqueous phase containing the product was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled and changed to acetone to a final volume of 550 ml. Fumaric acid (41.4 g, 0.36 mol) was added and the mixture heated to reflux for 1 hour. The suspension was cooled to 0° C., filtered and washed to afford 98.1 g (71% yield) of a solid consisting of a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 70%), intermediate 7 (ca 18%) and the 2,3-dihydroxymethyl impurity (ca 12%).
Example 11
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine as the fumarate salt in the presence of sodium bicarbonate
The reaction was carried out under the same conditions as disclosed in example 10, but using NaHCO 3 instead of sodium acetate.
The mixture was heated to 95° C. for 40 hours, after this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 62%), intermediate 7 (ca 32%) and the 2,3-dihydroxymethyl impurity (ca 5%).
Example 12
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the fumarate salt in the presence of sodium bicarbonate
A mixture of intermediate 7 (2 g of the fumarate salt, 0.0049 mol), xylene (4 ml) 40% aqueous formaldehyde (8 ml) and sodium bicarbonate (0.6 g) was heated to 95° C. for several hours. The relation of starting material (intermediate 7), final product (intermediate 11) and the 2,3-dihydroxymethyl impurity was monitored from time to time giving rise to the following results:
%
%
% 2,3-
Time
intermediate
intermediate
dihydroxy
(Hours)
7
11
methyl impurity
17
61.01
37.72
1.27
24
51.43
46.67
2.1
40
38.66
57.39
3.95
47
32.5
62.68
4.82
68
27.74
65.61
6.66
Example 13
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the fumarate salt in the presence of pyridine
A mixture of intermediate 7 (2 g of the fumarate salt, 0.0049 mol), xylene (4 ml) 40% aqueous formaldehyde (8 ml) and pyridine (0.46 g) was heated to 95° C. for several hours. The relation of starting material (intermediate 7), final product (intermediate 11) and the 2,3-dihydroxymethyl impurity was monitored from time to time giving rise to the following results:
%
%
% 2,3-
Time
intermediate
intermediate
dihydroxy
(Hours)
7
11
methyl impurity
17
43.67
52.66
3.67
24
31.91
62.22
5.87
40
16.64
71.39
11.97
47
12.28
69.22
18.5
68
10.76
64.97
24.27
Example 14
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) from intermediate 7 as the maleate salt
A mixture of intermediate 7 (2.2 g as the maleate salt, 0.0056 mol), xylene (4 ml) 40% aqueous formaldehyde (8 ml) and sodium acetate trihydrate (0.91 g) was heated to 95° C. for several hours. The relation of starting material (intermediate 7), final product (intermediate 11) and the 2,3-dihydroxymethyl impurity was monitored from time to time giving rise to the following results:
%
%
% 2,3-
Time
intermediate
intermediate
dihydroxy
(Hours)
7
11
methyl impurity
4.5
91.13
8.77
0.09
20.5
61.97
36.56
1.47
26.5
50.88
46.71
2.4
44
35.58
59.12
5.3
Example 15
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) from intermediate 7 as the succinate salt
A mixture of intermediate 7 (2.2 g as the succinate salt, 0.0056 mol), xylene (4 ml) 40% aqueous formaldehyde (8 ml) and sodium acetate trihydrate (0.91 g) was heated to 95° C. for several hours. The relation of starting material (intermediate 7), final product (intermediate 11) and the 2,3-dihydroxymethyl impurity was monitored from time to time giving rise to the following results:
%
%
% 2,3-
Time
intermediate
intermediate
dihydroxy
(Hours)
7
11
methyl impurity
4.5
73.65
25.73
0.62
20.5
18.02
74.65
7.32
26.5
11.03
77.94
11.03
44
3.78
77.35
18.23
Example 16
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) from intermediate 7 as the (+)-tartrate salt
A mixture of intermediate 7 (2.4 g as the tartrate salt, 0.0056 mol), xylene (4 ml) 40% aqueous formaldehyde (8 ml) and sodium acetate trihydrate (0.91 g) was heated to 95° C. for several hours. The relation of starting material (intermediate 7), final product (intermediate 11) and the 2,3-dihydroxymethyl impurity was monitored from time to time giving rise to the following results:
%
%
% 2,3-
Time
intermediate
intermediate
dihydroxy
(Hours)
7
11
methyl impurity
4.5
89.06
10.68
0.27
20.5
54.26
42.61
3.12
26.5
42.75
52.2
5.05
44
28.26
63.23
8.51
Example 17
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the fumarate salt without the presence of a base
The reaction was carried out under the same conditions as disclosed in example 10, but without addition of any base.
The mixture was heated to 95° C. for 32 hours, after this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 42%), intermediate 7 (ca 50%) and the 2,3-dihydroxymethyl impurity (ca 8%).
Example 18
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the fumarate salt in the presence of pyridine
The reaction was carried out under the same conditions as disclosed in example 10, but using pyridine instead of sodium acetate.
The mixture was heated to 95° C. for 32 hours, after this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 68%), intermediate 7 (ca 20%) and the 2,3-dihydroxymethyl impurity (ca 5%).
Example 19
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the fumarate salt in the presence of Triton B
The reaction was carried out under the same conditions as disclosed in example 10, but using Triton B instead of sodium acetate.
The mixture was heated to 95° C. for 32 hours, after this time a HPLC analysis showed a mixture of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) (ca 48%), intermediate 7 (ca 48%) and the 2,3-dihydroxymethyl impurity (ca 4%).
Example 20
Comparative Example
Preparation of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (Intermediate 11) following the methodology described in the prior art: EP 0 588 858
A mixture of intermediate 7 as the free base (5 g) and 40% aqueous formaldehyde was heated to reflux for 1 week. After this time a HPLC analysis showed a mixture of the starting material (intermediate 7—free base) and final product (intermediate 11) in a 50% ratio.
The reaction was cooled to 20° C., the pH was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The solvent was distilled off and the oil residue was purified by flash chromatography to obtain 1 g of 6,11-dihydro-3-hydroxymethyl-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine (intermediate 11) as the free base.
Spectroscopic Data of Intermediate 11 (Free Base):
1 H-NMR (400 MHz, DMSO-d6), δ: (1.95-2.05, 1H, m), 2.05-2.20 (1H, m), 2.13 (3H, s, CH 3 ), 2.25-2.35 (1H, m), 2.45-2.55 (1H, m), 2.55-2.65 (1H, m), 2.65-2.70 (1H, m), 2.70-2.80 (1H, m). 2.98 (1H, d, J=14.0 Hz), 3.37 (1H, dt, J=4.0, 14.0 Hz), 3.89 (1H, dt, J=4.0, 14.0 Hz), 4.30-4.40 (1H, m), 4.36 (2H, s), 4.90 (1H, broad s, OH), 6.77 (1H, s), 7.05 (1H, d, J=6.4 Hz), 7.15-7.25 (2H, m), 7.33 (1H, s, J=6.4 Hz).
13 C-NMR (100 MHz, DMSO-d6), δ: 30.0 (CH 2 ), 30.6 (CH 2 ), 30.7 (CH 2 ), 45.5 (CH 3 ), 46.0 (CH 2 ), 52.9 (CH 2 ), 56.2 (CH 2 ), 56.4 (CH 2 ), 124.2 (C), 125.8 (CH), 126.3 (CH), 127.4 (CH), 128.1 (CH), 128.2 (CH), 132.0 (C), 136.9 (C), 139.7 (C), 140.2 (C), 143.7 (C).
Example 21
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine-3-carboxaldehyde (Alcaftadine)
Intermediate 11 (88.4 g of the fumarate salt) was dissolved in dichloromethane (440 ml) and water (440 ml) and the pH was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The organic phase was distilled and the solvent was changed to toluene to a final volume of 440 ml. Manganese (IV) oxide (440 g) was added and the reaction was heated to 60° C. for 2 hours.
The reaction mixture was cooled down to 20° C. The solids were filtered off and washed with toluene (880 ml). The filtered liquids were concentrated to a final volume of 150 ml and diisopropyl ether (880 ml) was added. The solid was filtered and washed with diisopropylether. Crude Alcaftadine (49.5 g, 85%) was obtained with 90% purity.
Example 22
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5H-imidazo[2,1-b][3]-benzazepine-3-carboxaldehyde (Alcaftadine) in a One-Pot process from intermediate 7 as the fumarate salt
A mixture of intermediate 7 (5 g of the fumarate salt), xylene (10 ml) 40% aqueous formaldehyde (20 ml) and sodium acetate trihydrate (0.15 g) was heated to 95° C. for 20 hours. After this time a HPLC analysis showed a mixture of intermediate 11 (ca 70%), intermediate 7 (ca 15%) and the 2,3-dihydroxymethyl impurity (ca 15%).
The reaction was cooled to 20° C., and the two phases were separated. The pH of the aqueous phase containing the product was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane.
The organic phase was concentrated to a final volume of 25 ml, manganese (IV) oxide (25 g) was added and the suspension was refluxed for 2 hours.
The reaction mixture was cooled down to 20° C. The solids were filtered off and washed with dichloromethane (50 ml). The filtered liquids were concentrated to a final volume of 15 ml and diisopropyl ether (100 ml) was added. The solid was filtered and washed with diisopropylether. Crude Alcaftadine (2.4 g) was obtained with >90% purity.
Example 23
Preparation of 6,11-dihydro-11-(1-methyl-4-piperidinylidene)-5 5H-imidazo[2,1-b][3]-benzazepine-3-carboxaldehyde (Alcaftadine) in a One-Pot process from intermediate 7 as the succinate salt
A mixture of intermediate 7 (10 g of the succinate salt) and aqueous formaldehyde (40 ml) were heated to 95° C. for 20 hours. After this time a HPLC analysis showed a mixture of intermediate 11 (ca 70%), intermediate 7 (ca 15%) and the 2,3-dihydroxymethyl impurity (ca 15%).
The reaction was cooled to 20° C. The pH was adjusted to 9-10 by addition of 50% aqueous NaOH and the product was extracted with dichloromethane. The organic phase was concentrated to a final volume of 30 ml, manganese (IV) oxide (25 g) and water (3 ml) were added and the suspension was refluxed for 2 hours.
The reaction mixture was cooled down to 20° C. The solids were filtered off and washed with dichloromethane (50 ml). The filtered liquids were concentrated to a final volume of 15 ml and diisopropyl ether (100 ml) was added. The solid was filtered and washed with diisopropylether. Crude Alcaftadine (4.7 g) was obtained with >90% purity.
Example 24
Purification of Alcaftadine
In Ethyl Acetate
Crude Alcaftadine (2.3 g) was dissolved in dichloromethane/ethyl acetate. The dichloromethane solvent was distilled and changed to ethyl acetate, to a final volume of 11 ml. The suspension was cooled to 20° C. and the solid was filtered and washed with ethyl acetate and dried. Alcaftadine (1.5 g, 65% yield) was obtained with >99% purity.
In Isopropyl Alcohol.
Crude Alcaftadine (2.5 g) was suspended in isopropyl alcohol (25 ml) and the mixture was heated to 45/50° C. until all the product was dissolved. The solvent was distilled to a final volume of 7.5 ml and the suspension obtained was cooled to 20° C. The solid was filtered, washed with isopropanol and dried. Alcaftadine (1.7 g, 68% yield) was obtained with >99% purity.
Spectroscopic Data of Alcaftadine:
1 H-NMR (400 MHz, DMSO-d6), δ: 2.05-2.30 (2H, m), 2.19 (3H, s, CH 3 ), 2.30-2.40 (1H, m), 2.47 (1H, s), 2.55-2.75 (4H, m), 3.03 (1H, d, J=14.0 Hz), 3.39 (1H, td, J=3.6, 14.0 Hz), 4.15 (1H, td, J=2.8, 14.0 Hz), 4.62 (1H, d, J=14.0 Hz), 7.10 (1H, d, J=7.2 Hz), 7.24 (2H, quint, J=7.2 Hz), 7.35 (1H, d, J=7.2 Hz), 7.87 (1H, s), 9.60 (1H, s, CHO).
13 C-NMR (100 MHz, DMSO-d6), δ: 30.0 (CH 2 ), 30.6 (CH 2 ), 30.7 (CH 2 ), 45.1 (CH 3 ), 49.2 (CH 2 ), 55.8 (CH 2 ), 56.0 (CH 2 ), 123.3 (C), 126.7 (CH), 128.1 (CH), 128.5 (2×CH), 131.9 (C), 136.7 (C), 138.5 (C), 142.3 (CH), 143.7 (C), 149.6 (C), 179.5 (CHO). | The invention relates to new and improved processes for the preparation of Alcaftadine and pharmaceutically acceptable salts thereof as well as an intermediate for the preparation of Alcaftadine. The new process saves a number of steps compared to the known process and results in a higher yield. | 2 |
BACKGROUND OF THE INVENTION
The present invention concerns a drive for the driven drafting arrangement rolls of long spinning machines extending over the full length or over considerable parts of the length of the machine, preferably of ring spinning machines, in which the drafting arrangement rolls arranged on the same longitudinal side of the machine and defining a main drafting zone for the fibre slivers to be drafted, are mutually connected at one of their ends by first slippage-free transmission elements which effect the ratio of rotational speeds of these rolls determining the draft ratio.
With textile machines of this type there is a tendency, active since the very origins, to increase the number of working positions, e.g. of the spindles in the case of the ring spinning machine, driven by one single drive headstock. This tendency is prompted mainly by economic factors, as the increase in the number of working positions per machine results in a reduction of the price per working position, in a reduction of space per working position and in most cases, also in operating advantages.
One difficulty in achieving the above mentioned increase, however, is presented by the bottom rolls of the drafting arrangements of such machines, as in excessively long rolls the deformations caused by torsion can result in unacceptable working conditions. This concerns predominantly the rolls defining the main drafting zone of the drafting arrangement, i.e. e.g. the middle roll and the delivery roll of the double apron drafting arrangement, as widely used today on various spinning machines, preferentially on ring spinning machines, but also e.g. on the roving frame. In a main drafting zone of such type, the fibre mass is drafted to its final fineness before twist is imparted at a draft ratio of 10 fold and more, normally of about 30 fold. Any distortion, however small, of one roll active in the main drafting zone of a drafting arrangement with respect to the other roll immediately causes a considerable drafting defect resulting in a thick place and in a thin place in the drafted yarn. In many cases then very undesirable yarn breakages result. Experience with especially long spinning machines has shown, that the danger of distortion of the roll of the drafting arrangement is particularly great for the middle roll of a double apron drafting arrangement. Onto this roll, which as a rule also acts as a deflecting roll for the bottom apron of the double apron drafting arrangement, particularly strong braking forces act tangentially, which considerably exceed similar forces acting on the delivery rolls.
This difference is due to the rotational speed, which is reduced with respect to the delivery roll by the draft ratio, and due to the higher friction forces mainly generated by the apron which acts on this roll, and to the strong drafting forces acting on this roll in the predrafting zone. Due to these higher braking forces the middle drafting roll during the operation of the drafting arrangement thus is distorted to a higher degree than the delivery roll. If now the spinning machine is stopped, the forces acting tangentially upon the roll, and particularly the important drafting forces, are released to a large extent, in such manner that the input roll of the main draft zone, which is more distorted with respect to the delivery roll of the main drafting zone in the backward sense, tends to reverse this distortion and distort back in the normal sense of rotation. As the machine is thereafter started up, drafting defects generated in this manner already cause yarn breakages.
The situation described here for the drafting arrangement of the conventional spinning machine is further exacerbated in that during the subsequent start-up of the machine higher static friction forces are to be overcome by the input roll of the main drafting zone than by the delivery roll, which forces cause progressive distortion from the beginning of the input roll to its end. Also due to this distortion, the degree of which exceeds the distortion during normal operation, drafting defects and thus yarn breakages arise.
A reduction of the distortion mentioned by increasing the diameter of the rolls is excluded because of spinning technology requirements as an increase in diameter could be achieved only to the detriment of the quality of the fibre control during the drafting process.
Thus, it has been proposed already to avoid the above mentioned disadvantage of a long spinning machine by either driving the drafting rolls separately at both ends, in which arrangement the drafting rolls can be divided all the way or at the middle of the machine, as e.g. shown in U.S. Pat. No. 3,339,361 or by interconnecting the rolls at least in pairs via separate toothed gear drives, as shown in German DE-OS No. 26 41 434. All these proposed arrangements are suitable for avoiding the undesirable distortion of the rolls; they show, however, substantial disadvantages. Thus, they require a complete and exactly synchronous double drive for the drafting rolls. This solution is expensive, and still more important, it implies, at least in an arrangement using continuous rolls, a very dangerous source of errors. If the draft ratio in the main drafting zone, which is to be adapted by correspondingly choosing gears (draft change gears) or similar elements, due to operator's error is not set to the same value at both side, torsion-forced breakage of one of the rolls inevitably occurs. This solution thus requires highest attention of the operating personnel and thus runs contrary to the intentions of the spinning mills of facilitating easy and error-free operation of the spinning machine.
SUMMARY OF THE INVENTION
It thus is an object of the present invention to eliminate the mentioned disadvantages of the known solutions, and in particular to propose a drive for the drafting arrangement rolls of the above mentioned type, in which the continuous drafting arrangement rolls of the main drafting zone cannot mutually distort backward during the standstill of the machine, without requiring the rolls to be driven at both ends, or to be mutually interconnected.
This object is achieved, using a drive of the above mentioned type, by providing at the other end of the drafting arrangement rolls second, slippage-free transmission elements comprising a freewheel clutch, the ratio of rotational speeds of which elements is lower than the ratio of rotational speeds determining the draft ratio, which during normal operation of the machine permit either running behind or lag of the faster running roll or a lead of the slower running roll of the drafting arrangement, and which during the standstill of the faster running roll of the drafting arrangement effect a slippage-free connection via the transmission elements.
This solution achieves the result that, upon reaching machine standstill and upon release of load in the drafting arrangement, the determined torsion of the drafting arrangement roll built up during the operation of the machine, and in particular the input roll of the main drafting zone, which is strongly distorted in the lagging sense cannot distort back, but that the distortion is maintained also after the forces generating it (friction in the bearings, drafting forces) are released. This is achieved since during the standstill of the machine the drafting arrangement rolls at both ends are mutually interconnected slippage-free drive wise, namely on one end by the actual drafting arrangement gear drive, i.e. by the first slippage-free transmission elements, and on the other end by the second slippage-free transmission elements which, via the now activated freewheel clutch, are rigidly coupled drivewise. It is particularly advantageous that coupling of the rolls always is effected automatically at the exact moment at which the rolls stop, independently of the ratio of rotational speed prevailing between the rolls, determined by the first slippage-free transmission elements, i.e. independently of the drafting ratio. From this advantage results, that if the drafting ratio in the main drafting zone is changed, the operating personnel are not required to take care of the second slippage-free transmission elements at the other end of the rolls, a very dangerous source of errors thus being eliminated.
It has proven to be advantageous to choose the ratio of rotational speeds of the second slippage-free transmission elements just slightly lower than the ratio of rotational speeds of the first slippage-free transmission elements determining the minimum draft ratio chosen for the spinning machine. This measure ensures that the difference in rotational speeds to be overcome in the idling direction is kept as small as possible, in such manner that also the wear of the freewheel clutch is kept to a minimum. Furthermore, the proposed solution also proves advantageous with respect to the small play always present in slippage-free transmission elements (e.g. the play of the gear tooth flanks, if such transmission elements are provided), as defects caused by the backward distortion due to said play are kept to a minimum.
According to an alternative design example of the inventive drive the slower running roll of the drafting arrangement, i.e. the input roll of the main drafting zone, can be connected at its end provided with the second slippage-free transmission elements, with an element distorting the roll in the sense of its normal rotation using a second freewheel clutch, in such manner that the second freewheel clutch does not impair the rotation of the drafting arrangement roll during its normal operation, as it is overhauled, whereas during the standstill of the machine it effects the slippage-free connection.
Owing to this arrangement it is possible to eliminate the higher distortion of the slower running roll caused during the start-up of the machine by the higher static friction compared to the sliding or dynamic friction. Due to the higher static friction or due to the higher "breaking loose resistance" of the roll respectively, the slower running roll tends to lag behind with respect to the faster running roll, caused by a distortion in addition to the one suffered during the normal operation of the machine, i.e. it is rotated only after a certain time lag. This again causes a drafting defect, which depending on the distortion, is higher the longer the distance from the drive of the rolls is, e.g. the longer the rolls are. Even if this additional distortion of the slower running rolls is levelled out again immediately after the "breaking loose" of the rolls, it still can cause yarn breakages. It is possible for the slower running roll of the drafting arrangement at its end, at which the second transmission elements are arranged, to be connected via a second freewheel clutch with an element forcing the roll in its normal direction of rotation, and that the second freewheel clutch during the normal operation of the machine does not impair the rotation of the roll of the drafting arrangement whereas during the standstill of the machine it effects the slippage-free connection. By virtue of these it can be achieved, that the slower running drafting roll during the start-up of the machine is always pulled, so to speak towards the faster running roll at the stop, in such manner that it "breaks loose" always simultaneously with the faster running roll. The drive arrangement with the second freewheel clutch thus has the function of eliminating the effect of the difference between static friction acting on the slower running roll and the faster running roll and of ensuring that both rolls are started always synchronously. This measure, however, is only required, if the above mentioned difference in the effect of static friction is practically effective in the inventive drive, which depends to a large extent on the bearing type used.
BRIEF DESCRIPTION OF THE DRAWINGS
The inventive drive is explained in the following in more detail with reference to illustrated design examples. There is shown in
FIG. 1: a schematic, partially perspective view of a ring spinning machine with the inventive drive of the drafting arrangement rolls,
FIG. 2: a simplified, perspective view of an alternative design example of the drive, and
FIG. 3: the drive according to the alternative design example shown in FIG. 2, seen in the direction of arrow A of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 the elements of a spinning position of a ring spinning machine are shown schematically. They consist, as seen in the direction of material flow, of a roving bobbin 1 rotatably suspended from a rigid creel support 2, which supplies the roving 3 to be processed to a drafting arrangement. The drafting arrangement comprises three bottom rolls 4, 5 and 6 with corresponding pressure top rolls 7, 8 and 9. Arranged subsequently are a thread guide 10, a combination of ring 11 with a traveller 12 and a rotating spindle 13. The spindle 13 is rotatably supported in a ring rail 14 and supports a yarn bobbin 15, onto which the freshly spun yarn is wound, and is set into rotation by a belt 16.
The strand of fibres emerging from the pair of delivery rolls 6, 9 of the drafting arrangement, drafted to the required fineness is twisted in known manner under formation of a balloon 17 into a yarn and is wound onto the yarn bobbin 15.
The drafting arrangement comprises a first drafting zone (pre-draft zone) limited by the pairs of rolls 4, 7 and 5, 8 and a second drafting zone (main drafting zone), defined by the pairs of rolls 5, 8 and 6, 9. In the first drafting zone the roving 3 is drafted only slightly, e.g. 1 to 2 fold only, i.e. the difference in surface speed of the slower running rolls 4 and 7 with respect to the one of the faster running rolls 5 and 8 is small. Between the pairs of rolls 5, 8 and 6, 9 the fibre roving is drafted at a high draft ratio to the final yarn fineness. This second drafting zone thus is called the main drafting zone and the draft effected therein as a rule ranges between about 10 fold and 40 fold, in special cases up to 100 fold and more.
For better control of the fibre mass during the drafting operation in the main drafting zone as a rule so called double apron arrangements are used, here consisting of a bottom apron 18 surrounding the bottom roll 5 and of top apron 19 surrounding the top roll 8.
The bottom apron 18 as well as the top apron 19 are guided along the main drafting zone by suitable means (not shown) in FIG. 1 and are tensioned e.g. by tension rolls 20.
The fibre roving 3 now is guided between the legs or runs of the aprons 18 and 19 which are in mutual contact and are running parallel, in such manner that the fibre control required for high drafts is ensured. Such pairs of aprons 18, 19 are rotated only if considerable friction forces are overcome by the drive force of the driven roll 5 of the drafting arrangement. The roll 5 forms the input roll of the main drafting zone, whereas the roll 6 also is called delivery roll of the main drafting zone, or of the whole drafting arrangement, respectively. For simplified definitions the rolls 5 and 6 in the following description are referred to as the slower running roll and as the faster running roll, respectively, of the main drafting zone.
In a ring spinning machine referred to as long machine, about 250 spinning positions or more are lined up along one machine side. The rolls 4, 5 and 6 extending over all spinning positions of a machine side thus are of a length of about 18 to 35 m. For spinning technology reasons the diameter of the rolls 4, 5 and 6 is limited to a maximum of about 30 mm, and thus also their distortion resistance is relatively low.
The rolls 4, 5 and 6 of the drafting arrangement are driven from the right hand side by slippage-free transmission elements. The faster running roll 6 of the main drafting zone is directly driven by a motor 21 (sense of rotation according to arrow m).
The ratio of the numbers of teeth of the gears 24 and 22, the effective diameters of the rolls 5 and 6 being taken into account (and the thickness of the apron 18 on roll 5 also being taken into account) represents the drafting ratio in the main drafting zone. Of course, instead of gears also other slippage-free transmission elements, such as e.g. chains or toothed belts, can be applied. The important factor is just that the slower running roll 5 and the faster running roll 6 of the main drafting zone are interconnected by slippage-free transmission elements determining the drafting ratio.
The roll 4 of the drafting arrangement can be set into rotation e.g. from the slower running roll 5 of the main drafting zone also via slippage-free transmission elements, e.g. tooth gears 24, 25 and 26, in which gear train, according to the function of the pre-draft, the ratio of the numbers of teeth of the gears 26 and 24 is chosen small, normally in the range from 1 to 2. The rolls 4, 5 and 6 of the drafting arrangement are rotatably supported by a large number of bearings, not shown in FIG. 1, evenly distributed along the spinning machine.
For rotating the rolls 4, 5 and 6 the braking moments, generated by friction and causing a torque load on the roll, must be overcome. The slower running roll 5 is subject to a higher torque than the faster running roll 6, as the friction forces (e.g. generated by the apron assemblies) acting on it are considerably greater. Thus Also the distortion of the roll 5 is greater than that of roll 6, in such manner that as the torque moments acting onto the rolls disappear or are reduced (e.g. as the load on the pressing rolls 7, 8 and 9 is released), the slower running roll 5 tends to distort back in the direction of the arrow m more than the faster running roll 6. For preventing differing return-distortion of the rolls 5 and 6 during the standstill of the drafting arrangement, the rolls 5 and 6 are interconnected drive-wise at their free left hand side ends via further slippage-free transmission elements in such manner, that this connection is established only during the standstill of the faster running roll 6, whereas it remains inactive during operation. This is achieved in that a gear 27 rigidly mounted on the roll 6 is provided. The roll 5, on the other hand is provided with a freewheel clutch 28, shown in FIG. 1 as a ratchet arrangement for the sake of clearer understanding. A freewheel clutch of such type furthermore consists of an outer housing 29, which is connected with a hub 30 supported freely rotatable in bearings (not shown) on the roll 5 and which is provided with teeth 31 inside for a ratchet 32. The ratchet 32 is pivotably supported on the roll 5 and engages with the inside teeth 31 of the freewheel clutch 28 in such manner, that the outer housing 29 can rotate freely relative to the roll 5 clockwise (as seen from the left hand side). Counter-clockwise its freedom of rotation with respect to the roll 5 is blocked as the ratchet 32 engages with the teeth 31 on the inside, i.e. the clutch is engaged if rotated in this direction. The outer housing 29 furthermore is provided with a tooth gear 33 on its periphery, which via an intermediate gear 34 is engaged with the gear 27. In this arrangement the ratio of the numbers of teeth of the gears 33 and 27 always is lower than the one mentioned before which determines the draft ratio, between the gears 24 and 22. If a spinning machine is laid out for a determined range of draft ratios, it proves advantageous to choose the second mentioned ratio somewhat smaller than the one determining the lowest draft ratio for which the machine is laid out, in such manner that the arrangement can function at any draft ratio set at a given time. Adaption of the transmission ratio to the main draft ratio, however, can be envisaged for the second slippage-free transmission elements, e.g. by exchanging the gear 27.
The freewheel clutch 28, shown here as a ratchet arrangement with an inside ratchet, is not limited to this design type, however. A freewheel clutch of this type, chosen in FIG. 1 merely for the sake of simplicity, shows the disadvantage that it does not engage properly if the number of teeth is too small. For optimum functional reliability of the inventive drive a freewheel clutch with a small lost motion is to be provided, i.e. one which can engage at practically any position immediately.
The drive according to FIG. 1 now functions as follows:
During operation of the machine the outer housing 29 of the freewheel clutch is rotated clockwise by the gears 27, 34, 33 faster than the slower running roll 5 of the drafting arrangement, i.e. the freewheel clutch is disengaged. Before the rolls 5 and 6 come to a standstill they are still distorted, the distortion of the slower running roll 5 being greater than that of the faster running roll 6. Now after stopping, e.g. by releasing the load on the pressure rolls 8 and 9, the friction forces acting onto the rolls 5 and 6 are diminished. Thus the rolls 5 and 6 tend to reduce their distortion, i.e. the roll 5 tends to distort back over a limited amount more than the roll 6 clockwise. This movement, however, of the roll 5 is blocked, as the ratchet 32 immediately engages with the inside teeth 31 of the freewheel clutch 28. The outer housing 29 thus also is driven clockwise for a limited rotation and tends to transmit this movement via the gears 33, 34, 27 to the stopped roll 6 of the drafting arrangement. The rolls 5 and 6 defining the main drafting zone thus are interconnected at both ends during the standstill of the machine via slippage-free transmission elements: and any relative rotation of the rolls, which would result in a drafting defect upon restarting the machine, is excluded.
As soon as the spinning machine is started up again the blocking action of the freewheel clutch 28 is released, as its outer housing 29 leads the slower running roll 5, i.e. rotates faster in the same direction than the roll 5.
In FIGS. 2 and 3, in which the elements identical with the ones shown in FIG. 1 are designated with the same reference numbers, an alternative embodiment of the inventive drive is shown, which differs from the one shown in FIG. 1 only in that here the freewheel clutch 35, the function of which corresponds to the clutch 28 of FIG. 1, is arranged on the faster running roll 6 of the drafting arrangement. For simplifying the drawing, only the two rolls 5 and 6 defining the main drafting zone of the drafting arrangement are shown. In FIG. 2 a perspective view of the drive similar to the view illustrated in FIG. 1 is shown, whereas in FIG. 3 the drive according to FIG. 2 is shown as seen in the direction of arrow A.
In this alternative design example the freewheel clutch 35 is designed as a so called roller blocking arrangement with spring type friction elements, i.e. a freewheel clutch which can engage practically without any lost motion.
A roller blocking arrangement of this type consists of an outer ring 36, which is rigidly connected with a concentrical gear 37 and is supported freely rotatable in bearings not shown on the roll 6 of the drafting arrangement.
The gear 37 meshes with an intermediate gear 38 which is engaged with a gear 39 rigidly mounted on the slower running roll 5, and also in this arrangement the ratio of the numbers of teeth of the gears 39 and 37 is chosen smaller than the corresponding ratio of the gears 24 and 22, i.e. is smaller than the main draft.
On the roll 6 a star wheel 40 is rigidly mounted and arranged within the hollow interior of the outer ring 36, which star wheel 40 is provided with teeth 41 (FIG. 3) pivoted in the clockwise sense. Between the teeth 41 rollers 42 are inserted which are pressed by springs 43 into the wedge-shaped chambers formed between the tooth intervals and the outer ring 36. A roller blocking arrangement of such type, which is commercially available, permits free rotation of the starwheel 40 with respect to the outer ring 36 in one direction, in the example shown in clockwise direction, in the outer direction, however, any relative movement is blocked as the rollers 42 jam, the jamming becoming practically without any lost motion, as the rollers 42 are clamped immediately.
The function of this drive corresponds substantially to that of the drive described with reference to FIG. 1 and thus is not described in more detail. In this arrangement the slower running roll 5 when it comes to standstill tends to distort back clockwise with respect to the faster running roll 6 (always as seen from the lefthand side); this is blocked, however, by the action of the freewheel clutch 35, which immediately engages as its outer ring 36 is driven with respect to the star wheel 40 clockwise.
During the normal operation of the spinning machine the outer ring 36, owing to the transmission described, is rotated slower than the star wheel 40, or the faster running roll 6, respectively, i.e. the freewheel clutch runs behind the roll 6.
The alternative design example according to FIGS. 2 and 3 furthermore shows in which manner the slower running roll 5 of the drafting arrangement at its end, on which the second transmission elements 37 through 39 are arranged, via a second freewheel clutch 44, which is identical in its design with the freewheel clutch 35, is connected with an element 45, which distorts the roll 5 in the direction of its normal rotation, i.e. clockwise (as seen from the left hand side), in such manner that the freewheel clutch 44 during the normal operation of the machine does not impair the rotation of the roll 5 of the drafting arrangement, whereas it effects, as the machine comes to a standstill, the connection between the element 45 and the roll 5.
In the example shown in FIGS. 2 and 3 the element 45 consists of a lever 46, which is rigidly connected to the outer ring 47 of the freewheel clutch 44 and a pneumatic cylinder 48, the piston rod 49 of which is pivotably connected with the other end of the lever 46.
The cylinder 48 is pivotably supported on an axle 50 which is fixed relative to the room. The piston rod 49 is held during the operation of the spinning machine in its lefthand side position (shown with solid lines in FIG. 3) by a pressure spring, as the piston 51 is not subject to pressure. In this position the outer ring 47 of the freewheel clutch 44 thus remains at a standstill, whereas its star wheel 53 freely rotates clockwise together with the roll 5.
The additional device described here merely serves for overcoming the static friction forces acting upon the slower running roll 5 of the drafting arrangement during the startup phase of the spinning machine.
The additional device functions as follows: Before the spinning machine is started up the pneumatic cylinder 48 is pressurized. The piston 51 with its piston rod 49 now tends to rotate the lever 46 clockwise. As the slower running roll 5 still is at standstill, the freewheel clutch 44 is engaged. The lever 46 thus generates a torque moment in clockwise direction (as seen from the left) acting onto the roll 5. The spinning machine now is started up and the static friction forces acting upon the rolls of the drafting arrangement are to be overcome. This is effected by the torque moment mentioned which acts from the freewheel clutch 44 onto the slower running roll 5 and transmitted via the gears 39, 38 and 37 and the freewheel clutch 35, also acts onto the faster running roll 6, which torque moment is to be considered as "breaking loose" moment. In this process the lever 46 is rotated over the angle α to the stop of the piston 51 (position of the lever 46 indicated with broken lines in FIG. 3). As the start-up of the spinning machine is completed, or as the lever 46 rests against its right hand side stop, the freewheel clutch 44 is overtaken by its star wheel 53, in such manner that the rotational connection between the drive element 45 and the roll 5 of the drafting arrangement is released.
The pneumatic cylinder 48 in this arrangement can be activated independently in time from the spinning machine, i.e. it can be activated at any time during the standstill of the machine. This, because the torque moment exerted onto the roll 5 of the drafting arrangement, owing to the inventive blocking of the roll 5 during the standstill of the machine, cannot result in any distortion of the roll 5 in this direction. The torque moment however, is always available immediately for the start-up of the machine. The dimensions of the components of the element 45 (diameter and lift of the pneumatic cylinder 48, pressure in the cylinder, position of the lever 46, etc) depend on the static friction forces to be overcome and are chosen according to experiment.
While there are shown and described present preferred embodiments of the invention, it is to be distictly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly, | A drive for the rolls defining a main drafting zone of drafting arrangements of long spinning machines, wherein in order to prevent drafting defects caused by distortion movement of the rolls, the latter are driven from one end by a first gear arrangement and from the other end are interconnected rigidly drivewise or slippage-free, respectively, during the standstill of the spinning machine via a second gear arrangement and via a freewheel clutch. | 3 |
FILED OF THE INVENTION
This invention relates to a process for producing an unsaturated group-terminated high-molecular weight polyalkylene oxide.
BACKGROUND OF THE INVENTION
A polyalkylene oxide having an unsaturated end group is useful as a crosslinking agent or a modifier in vinyl polymerization.
The reaction between an unsaturated group-terminated polyalkylene oxide and a hydrosilane having a hydrolyzable group produces a polymer having a crosslinking silicon end group which is useful as a moisture-curing polymer as disclosed in JP-A-52-73998 (the term "JP-A" as used herein means an "unexamined published Japanese patent application").
The polyalkylene oxides are, in most cases, required to have a high molecular weight of from about 5,000 to 20,000. However, such a high-molecular weight polyalkylene oxide is not readily available on the market.
JP-A-53-134095 discloses a process for producing an unsaturated group-terminated high-molecular weight polyalkylene oxide, in which a hydroxyl-terminated polyalkylene oxide having a relatively low molecular weight is used as a starting material, which comprises converting the hydroxyl end group to an alkoxide group in the presence of an alkali metal hydroxide (alkoxidation). Thereafter a plurality of the polyalkylene oxide molecules are connected to one another by using a polyhalogen compound to increase the molecular weight of the starting polyalkylene oxide (1st step), and then the hydroxyl end groups are converted to unsaturated groups by using an unsaturated halogen compound. This process is illustrated by the following reaction scheme: ##STR1##
This reference additionally discloses a process in which an alkali metal or an alkali metal compound, capable of producing an alkali metal hydroxide on reaction with water, such as an alkali metal hydride and an alkali metal alkoxide, (hereinafter an alkali metal and an alkali metal compound will be inclusively referred to as an alkoxidizing agent) can be used in place of the alkali metal hydroxide to alkoxidize the hydroxyl end group. Because such alkoxidizing agents have a higher activity than an alkali metal hydroxide, an about equivalent amount of the alkoxidizing agent can be used to conduct the reaction so that purification of the product is easy. However, when the reaction scheme shown above is followed using alkoxidizing agents, the increase in molecular weight and the ability to introduce an unsaturated bond to the product produced in the first step are insufficient, which highligths the fact that the reaction conditions must be strictly controlled before a desired reaction can proceed.
SUMMARY OF THE INVENTION
An object of this invention is to provide a process for producing an unsaturated group-terminated high-molecular weight polyalkylene oxide by using an alkoxidizing agent which makes purification of the product easy.
Another object of this invention is to provide a process for producing an unsaturated group-terminated high-molecular weight polyalkylene oxide in which the increase in molecular weight the introduction of an unsaturated group proceeds easily and sufficiently.
The inventors have conducted extensive investigations and have found that the above objects are accomplished by a process which comprises adding an alkali metal and/or an alkali metal compound capable of producing an alkali metal hydroxide on reacting with water to a hydroxyl-terminated polyalkylene oxide comprising a repeating unit represented by formula --R 1 --O-- (wherein R 1 represents a divalent alkylene group having from 2 to 8 carbon atoms) to substitute the hydrogen atom of the hydroxyl end group with an alkali metal (alkoxidation), reacting the resulting polyalkylene oxide with a polyhalogen compound to increase the molecular weight of the polyalkylene oxide (hereinafter referred to as a 1st step), and reacting the resulting high-molecular weight polyalkylene oxide with an unsaturated halogen compound to introduce an unsaturated group to the molecular chain terminals (hereinafter referred to as a 2nd step), wherein said alkali metal and/or alkali metal compound capable of producing an alkali metal hydroxide on reaction with water is added before the 1st step in an amount equivalent to or less than the number of hydroxyl end groups of said polyalkylene oxide and then before the 2nd step additional alkali metal and/or alkali metal compounds are added to the reaction mixture in an amount equivalent to or greater than the remaining hydroxyl end groups.
DETAILED DESCRIPTION OF THE INVENTION
The process of the present invention is characterized in that alkoxidation of the hydroxyl end groups of the starting polyalkylene oxide with an alkoxidizing agent is carried out in two divided stages, once before the 1st step (increase of molecular weight) and then before the 2nd step (introduction of an unsaturated group), to different degrees.
The reason why the alkoxidation reaction realizes progresses so easily to produce high of molecular weight products with introduced unsaturated groups can be accounted for as follows:
In the process of JP-A-53-134095, alkoxidation is effected only once by using a nearly equivalent amount of an alkoxidizing agent, e.g., an alkali metal and a highly active alkali metal compound, before the 1st step as described in the working examples. According to this process, if water is incorporated into the reaction system during or after the reaction progress in the 1st step, the alkoxide group is converted back to a hydroxyl group so that the subsequent 2nd step hardly proceeds. To avoid such an occurrence, the reaction system should be strictly controlled in an amount of the alkoxidizing agent and completely free from moisture.
Further, if the alkoxidizing agent is used in excess in the alkoxidation reaction before the 1st step in an attempt to facilitate progress of the 2nd step, undesired side reactions occur. For example, the reaction illustrated below would take place during the 1st step, resulting in the failure to increase the molecular weight of the starting polyalkylene oxide: ##STR2##
In the process according to the present invention, such disadvantages are eliminated, and an increase in molecular weight and the introduction of an unsaturated group proceed quite easily.
The starting polyalkylene oxide to be used in the present invention is a polymer essentially comprising a repeating unit represented by formula --R--O-- (wherein R 1 represents a divalent alkylene group having from 2 to 8 carbon atoms) and having a hydroxyl group at the terminal(s) thereof. Suitable polyalkylene oxides are those wherein R 1 has from 2 to 4 carbon atoms.
A part of the hydrogen atoms of the alkylene group R 1 may be substituted with other atom or atomic group. The polyalkylene oxide may be comprised of only the above-described repeating unit (--R 1 --O--) or may further contain other repeating units. In the latter case, the proportion of the repeating unit of formula --R 1 --O-- is at least 50% by weight, and preferably at least 80% by weight. The polyalkylene oxide may be either linear or branched. Linear polyalkylene oxides are frequently used.
The starting polyalkylene oxide should be terminated by a hydroxyl group, but all the end groups may not be hydroxyl groups, and part of them may be other groups, e.g., a methoxy group and an allyloxy group. A necessary minimum number of hydroxyl groups per polymer molecule is 1.1, preferably 1.5, in average.
The starting polyalkylene oxide mostly has a degree of polymerization of about 100.
Specific examples of suitable starting polyalkylene oxides include polyoxyalkylene polyols, e.g., polyoxyethylene glycol, polyoxyethylene triol, polyoxyethylene tetraol, polyoxypropylene glycol, polyoxypropylene triol, polyoxypropylene tetraol, polyoxybutylene glycol, polyoxytetramethylene glycol, polyoxypentane glycol, polyoxyhexane glycol, polyoxyheptane glycol, and polyoxyoctane glycol. These polymers may be used either individually or in combinations of two or more.
The alkoxidizing agent which can be used to convert the hydroxyl end groups of the polyalkylene oxides to alkoxide groups include alkali metals, e.g., Na and K; and alkali metal compounds capable of producing an alkali metal hydroxide on reaction with water. Such alkali metal compounds include alkali metal hydrides, e.g., NaH and KH, and alkalr metal alkoxides, e.g., CH 3 ONa, CH 3 OK, C 2 H 5 ONa, and C 2 H 5 OK. The preferred compound is an alkali metal alkoxide because it can be used in the form of a solution and evolves no combustible gas such as hydrogen. Solvents which can be used for dissolving alkali metal alkoxides include alcohols, e.g., methanol and ethanol.
In the first alkoxidation reaction which is conducted before the 1st step, the alkoxidizing agent is used in an amount equivalent to or less than the hydroxyl groups in the starting polyalkylene oxide, preferably of from 80 to 100% eq. When the reaction system contains water and the like, the alkoxidizing agent is also consumed by reaction with water. This being the case, the alkoxidizing agent should be added in an increased amount accordingly.
What is important is that the alkoxidizing agent should not be present in excess in the reaction system before the 1st step. As a matter of course, only a slight excess of the alkoxidizing agent may remain in the reaction system to be subjected to the 1st step as long as the objects of the present invention are fulfilled.
Reaction conditions of alkoxidation are not particularly limited, and conventional conditions of temperature and pressure can be used. When an alkali metal alkoxide is used as, the alkoxidizing agent, the reaction is preferably carried out at a high temperature of 50° C. or more, preferably between 100° C. and 200° C., under reduced pressure of not more than 50 mmHg, preferably not more than 10 mmHg, in order to drive alcohol, a by-product of the reaction, out of the system.
Specific examples of suitable polyhalogen compounds which can be used in the 1st step (to increase the molecular weight of the starting polyalkylene oxides) are methylene chloride, chloroform, carbon tetrachloride, methylene bromide, methyleneiodide,monochloromonobromomethane,1,1-dichloro-2,2-dimethylpropane, benzal chloride, benzal bromide, bis(chloromethyl)benzene, bis(bromomethyl)benzene, tris(chloromethyl)benzene, 4,4'-bis(chloromethyl)biphenyl, and bis(chloromethyl)naphthalene. These polyhalogen compounds may be used either individually or in combinations of two or more. Preferred polyhalogen are dihalogen alkylene compounds, e.g., methylene chloride and methylene bromide.
The reaction of the 1st step can be carried out at a temperature of from 0° to 200° C. under normal or reduced pressure without any particularly limits on reaction conditions. Through the 1st step, the relatively low molecular weight of the starting polyalkylene oxide (about 500 to 5,000) is increased to about 1,000 to 20,000.
In the second alkoxidation reaction which is conducted before the 2nd step, the amount of the alkoxidizing agent to be added is at least equivalent to the hydroxyl end groups of the high-molecular weight polyalkylene oxide obtained in the 1st step. However, too large an excess results in an increase of by-products in the following steps, which will complicate purification. In general, the alkoxidizing agent is preferably added in such an amount that the alkoxidizing agent may be present in the reaction system after completion of alkoxidation of the hydroxyl end groups in 5 to 50 % eq. excess to the alkoxide end groups.
The unsaturated halogen compound which can be used in the 2nd step preferably includes organic halogen compounds having a vinyl group, a highly reactive unsaturated group, and represented by the formula CH 2 ═CH--R 2 --X (wherein R 2 represents a divalent organic group; and X represents a halogen atom). Specific examples of such an unsaturated halogen compound are allyl chloride, allyl bromide, vinyl(chloromethyl)benzene, allyl(chloromethyl)benzene, allyl(bromomethyl)benzene, allyl chloromethyl ether, allyl(chloromethoxy)benzene, 1-butenyl chloromethyl ether, 1-hexenyl(chloromethoxy)benzene, and allyloxy(chloromethyl)benzene. These unsaturated halogen compounds may be used either individually or in combinations of two or more.
The reaction of the 2nd step can be carried out under the same conditions as in the 1st step without any particular limits on reaction conditions.
Upon completion of the 2nd step, there is obtained an unsaturated group-terminated high-molecular weight polyalkylene oxide. Thereafter, the product can be isolated through conventional purification procedures.
By the process of the present invention, there can be easily produced an unsaturated group-terminated high-molecular weight polyalkylene oxide having a molecular weight of, e.g., from about 5,000 to 20,000 and containing unsaturated end groups in an amount of, e.g., 90 mol % or more.
The present invention is now illustrated in greater detail with reference to the following Examples, but it should be understood that the present invention is not construed as being limited thereto. All the percents are by weight unless otherwise indicated.
EXAMPLE 1
In a 1 l-volume pressure vessel equipped with a stirrer in which the atmosphere had been displaced with nitrogen was charged 320 g (0.10 mol) of polyoxypropylene glycol having an average molecular weight of 3,200 and containing hydroxyl end groups in a proportion of 89% based on the total end groups (the remaining end groups were unsaturated groups, e.g., an isopropenyl group). Subsequently, 30.9 g of a 28% solution of sodium methoxide in methanol (sodium methoxide content: 8.66 g, 0.16 mol) was added thereto (lst alkoxidation). The temperature was raised to 130° C., and the vessel was evacuated for 2 hours. When the inner pressure was reduced to 1 mmHg, 5.1 g (0.06 mol) of dichloromethane was added thereto to conduct a reaction at 130° C. for 4 hours (lst step).
The reaction system having been subjected to the first alkoxidation before the 1st step reaction was analyzed by infrared spectrophotometry to determine the intensity of the absorption spectrum assigned to a hydroxyl group which appears in the vicinity of 3500 cm -1 . It was proved, as a result, that 90% of the hydroxyl groups contained in the starting polyoxypropylene glycol had been converted to methoxide groups.
Then, 10.3 g of a 28% solution of 2.89 g (0.054 mol) of sodium methoxide in methanol was added to the reaction system, and the vessel was evacuated at 130° C. for 1 hour (second alkoxidation). When the inner pressure was reduced to 1 mmHg, 8.0 g (0.105 mol) of allyl chloride was added thereto to conduct a reaction at 130° C. for 2 hours (2nd step). The reaction system after the second alkoxidation before the 2nd step was found to contain 0.03 mol of sodium methoxide.
After completion of the 2nd step reaction, the reaction product was diluted with 1000 g of n-hexane, and 50 g of aluminum silicate was added to the solution. The mixture was stirred for 1 hour and filtered. The filtrate was evaporated to remove the volatile content to obtain 300 g of a polypropylene oxide polymer having an average molecular weight of 8000. The end groups of the resulting polymer were found to comprise 98% of an unsaturated group and 2% of a hydroxyl group.
EXAMPLES 2 TO 5
An unsaturated group-terminated high-molecular weight polyalkylene oxide was produced in the same manner as in Example 1, except that various alkoxidizing agents, polyhalogen compounds and unsaturated halogen compounds were used, and the reactions were conducted under various conditions as shown in Table 1. The results obtained are shown in the Table 1.
TABLE 1__________________________________________________________________________ Example 1 Example 2 Example 3 Example 4 Example__________________________________________________________________________ 51st Alkoxidation:Alkoxidizing agent 28% CH.sub.3 ONa 28% CH.sub.3 ONa 20% CH.sub.3 OK 24% CH.sub.3 ONa 20% 3OK(g) 30.9 30.9 56.2 36.0 56.2(mol) 0.160 0.160 0.160 0.160 0.160Reaction Temp. (°C.) 130 150 100 130 130Reduced Pressure (mmHg) 1 1 5 3 2Reaction Time (hr) 2 1 2 1 2Rate of Alkoxidation (%) 90 90 90 90 90Mol. Wt. Increase:Polyhalogen Compound CH.sub.2 Cl.sub.2 CH.sub.2 BrCl CH.sub.2 Cl.sub.2 ClCH.sub.2 OCH.sub.2 CH.sub.2 Br.sub.2(g) 5.1 7.8 5.1 8.7 11.2(mol) 0.060 0.060 0.060 0.077 0.063Reaction Temp. (°C.) 130 80 120 100 70Reaction Time (hr) 4 3 3 5 42nd Alkoxidation:Alkoxidizing Agent 28% CH.sub.3 ONa 28% CH.sub.3 ONa 20% CH.sub.3 OK 24% CH.sub.3 ONa 20% CH.sub.3 OK(g) 10.3 13.5 18.7 12.0 12.5(mol) 0.054 0.070 0.053 0.053 0.036Reaction Temp. (°C.) 130 150 120 130 110Reduced Pressure (mmHg) 1 2 5 5 3Reaction Time (hr) 1 2 1 1 1Excess of Metal 0.03 0.05 0.03 0.03 0.015Alkoxide (mol)Introduction of UnsaturatedGroup:Unsaturated Halogen CH.sub.2CHCH.sub.2 Cl CH.sub.2CHCH.sub.2 Br CH.sub.2CHCH.sub.2 CH.sub.2CHCH.sub.2 Cl CH.sub.2CHCH.sub.2Compound ##STR3## OCH.sub.2 Cl(g) 8.0 12.2 26.3 10.1 13.9(mol) 0.105 0.101 0.144 0.131 0.131Reaction Temp. (°C.) 130 100 120 130 100Reaction Time (hr) 2 2 2 3 3Produced PolyoxypropyleneGlycol:Average Molecular Weight 8000 7900 8100 9500 9000Olefin End Group (%) 98 98 97 98 98OH group (%) 2 2 3 2 2Starting PolyoxypropyleneGlycol:Average Molecular Weight 3200 3200 3200 3200 3200OH Group (%) 89 89 89 89 89(equivalent) 0.178 0.178 0.178 0.178 0.178Amount Used (g) 320 320 320 320 320(mol) 0.1 0.1 0.1 0.1 0.1__________________________________________________________________________
EXAMPLES 6 TO 9
An unsaturated group-terminated high-molecular weight polyalkylenc oxide was produced in the same manner as in Example 1, except that the starting polyoxypropylene glycol was replaced with each of the polyoxyalkylene polymers shown in Table 2 below and the reactions were conducted under the conditions shown in the Table.
TABLE 2__________________________________________________________________________ Example 6 Example 7 Example 8 Example 9__________________________________________________________________________1st Alkoxidation:Alkoxidizing Agent 28% CH.sub.3 ONa 28% CH.sub.3 ONa 28% CH.sub.3 ONa 28% CH.sub.3 ONa(g) 102.1 74.2 31.3 62.5(mol) 0.529 0.385 0.162 0.324Reaction Temp. (°C.) 130 130 130 130Reduced Pressure (mmHg) 1 1 1 1Reaction Time (hr) 2 2 2 2Rate of Alkoxidation (%) 90 90 90 90Mol. Wt. Increase:Polyhalogen Compound CH.sub.2 Cl.sub.2 CH.sub.2 Cl.sub.2 CH.sub.2 Cl.sub.2 CH.sub.2 Cl.sub.2(g) 21.7 5.6 5.1 13.7(mol) 0.255 0.066 0.06 0.161Reaction Temp. (°C.) 130 130 130 130Reaction Time (hr) 4 4 4 42nd Alkoxidation:Alkoxidizing Agent 28% CH.sub.3 ONa 28% CH.sub.3 ONa 28% CH.sub.3 ONa 28% CH.sub.3 ONa(g) 22.7 16.5 7.0 13.9(mol) 0.118 0.086 0.036 0.072Reaction Temp. (° C.) 130 130 130 130Reduced Pressure (mmHg) 1 1 1 1Reaction Time (hr) 1 1 1 1Excess of Metal 0.05 0.04 0.01 0.03Alkoxide (mol)Introduction of Unsaturated Group:Unsaturated Halogen CH.sub.2 ═CHCH.sub.2 Cl CH.sub.2 ═CHCH.sub.2 Cl CH.sub.2 ═CHCH.sub.2 Cl CH.sub.2 ═CHCH.sub.2 ClCompound(g) 10.8 10.8 10.8 10.8(mol) 0.141 0.141 0.141 0.141Reaction Temp. (°C.) 130 130 130 130Reaction Time (hr) 2 2 2 2Produced Polyalkylene Oxide:Average Molecular Weight 8000 9000 8300 11500Olefin End Group (%) 96 98 97 98OH Group (%) 4 2 3 2Starting Polyalkylene Oxide:Kind polyoxy- polyoxy- polyoxy- polyoxy- ethylene propylene tetramethyl- hexane glycol triol lene glycol glycolAverage Molecular Weight 1200 2800 3500 2200OH Group(%) 98 95 90 90(mol) 0.588 0.428 0.18 0.36Amount Used(g) 360 420 350 440(mol) 0.3 0.15 0.1 0.2__________________________________________________________________________
COMPARATIVE EXAMPLE
An unsaturated group-terminated high-molecular weight polyoxyalkylene was produced in the same manner as in Example 1, except that alkoxidation was carried out only once prior to completion of the 1st step (molecular weight increased by using sodium methoxide in an amount equivalent to a hydroxyl group of the starting polyoxypropylene glycol, followed by the molecular weight increase reaction and then the reaction for introducing of the unsaturated end group. The resulting polymer had a low content of an unsaturated end group.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A process for producing an unsaturated group-terminated high-molecular weight polyalkylene oxide by adding an alkali metal and/or an alkali metal compound capable of producing an alkali metal hydroxide on reaction with water to a hydroxyl-terminated polyalkylene oxide having a repeating unit represented by formula --R 1 --O-- (wherein R 1 represents a divalent alkylene group having from 2 to 8 carbon atoms) to substitute the hydrogen atom of the hydroxyl end group with an alkali metal (alkoxidation) the resulting polyalkylene oxide is reacted with a polyhalogen compound to increase the molecular weight of the polyalkylene oxide and then additional alkali metal and/or alkali metal compound is added before reacting the resulting high-molecular weight polyalkylene oxide with an unsaturated halogen compound to introduce an unsaturated group to the molecular chain terminals. The first addition of alkali metal and/or alkali metal compound capable of producing an alkali metal hydroxide on reacting with water is added in an amount equivalent to or less than the hydroxyl end groups of said polyalkylene oxide and second addition of alkali metal and/or alkali metal compound is added in an amount equivalent to or greater than the remaining hydroxyl end groups. | 2 |
FIELD OF THE INVENTION
The present invention generally relates to amplifier linearization, and more specifically to an apparatus and a method of dynamically adapting a look up table (LUT) spacing for linearizing a power amplifier (PA).
BACKGROUND OF THE INVENTION
Power efficiency of a power amplifier is a crucial issue in wireless communication systems. A stand-alone class-A PA suffers the problem of low power efficiency. On the other hand, a stand-alone power efficient PA, like class-AB or class-B amplifier, is usually highly nonlinear. When a non-constant-envelope modulated signal goes through a nonlinear PA, inter-modulation distortion (IMD) will emerges. This not only distorts the modulated signal but also causes the power spectrum of the modulated signal to overflow to the adjacent channels. As a result, both self-interference and mutual-interference among neighboring channels seriously degrade the communication quality. In order to maintain power efficiency and suppress IMD, it is a common practice to adopt a nonlinear PA with high power efficiency.
There exist a few schemes for PA linearization, such as the feed-forward scheme, the feedback scheme, and the predistortion scheme. Each is with either analog approaches or digital approaches. Generally speaking, the feed-forward schemes are costly and the feedback schemes are limited to only narrow band applications. All the analog approaches are inflexible. Therefore, in terms of cost effectiveness, the digital predistortion schemes are superior to the others.
Shown in FIG. 1 is a block diagram illustrating the linearization of a digital predistorter (PD). The digital PD 101 predistorts a modulated input signal v m to invert the nonlinear distortion introduced by a PA 107 . In particular, a digital adaptive PD (DAPD) employing a gain-based look up table 101 a is very attractive for its flexibility in algorithm adaptation and its high accuracy in nonlinear compensation. As shown in FIG. 1 , the complex baseband modulated input signal v m carrying the payload data is fed to the cascade of the PD 101 and a radio frequency (RF) link. The PD 101 distorts the modulated input signal v m to produce a predistorted signal v d . The RF link takes over the predistorted signal v d , to generate the transmission signal v a , through a digital-to-analog (D/A) converter 103 for transformation, a quadature modulator 105 for frequency up-conversion, and the PA 107 for power amplification.
Because the characteristics of a PA may vary with temperature and may be affected by aging, an adaptive algorithm is required in a DAPD-LUT scheme to update the LUT entry values. In addition, the linearization accuracy of a DAPD-LUT scheme in terms of IMD will improve 6 dB if one doubles the number of LUT entries. However, the more LUT entries one adopts, the lower LUT convergence speed it will suffer.
Several gain-based LUT techniques are either analyzed or implemented. FIG. 2 is a block diagram illustrating a conventional gain-based DAPD-LUT technique that the indexing of the N-size LUT entries is uniformly spaced, wherein the normalized unsaturated input amplitude range of a PA is [0, 1] and an LUT entry's spacing d i equals to 1/N. However, in the uplink or downlink of a wireless network, most transmitted signals do not occupy the input amplitude range of the entire PA. Some LUT entries will never be selected. Therefore, a non-uniform LUT spacing technique is highly desired to avoid wasting LUT entries.
FIG. 3 is a block diagram illustrating a conventional gain-based DAPD-LUT technique with an optimum non-uniform LUT spacing, wherein the LUT is indexed by the input amplitude r m of input modulated signal via a mapper S(r m ) to implement a non-uniform LUT spacing d i , which is referred to as the conditionally-optimum spacing technique. The technique assumes knowledge of the conditions on the input signal backoff (IBO), the PA characteristics, and the probability density function (PDF) of the modulated input signal. When any of the assumed knowledge varies with time, the optimum LUT spacing needs to be recalculated. Unfortunately, the computational complexity of recalculating the LUT spacing in such a conditionally optimum technique is pretty high.
Since the conditionally optimum technique is optimum only under a specific set of conditions, any condition mismatch could cause significant performance degradation. However, some of conditions are difficult to accurately obtain, e.g. the PA characteristics, and some of conditions can be fast time-varying, e.g. the IBO. In addition, the computational complexity of the conditionally optimum technique thwarts any attempt to online optimize the LUT spacing for a different set of conditions. Therefore, an unconditionally optimized technique is practically useful.
FIG. 4 is another conventional gain-based DAPD-LUT technique with a non-uniform LUT spacing, which is referred to as the piecewise-uniform spacing technique. In the piecewise uniform spacing technique, the whole unsaturated PA input amplitude range is first artificially divided into several segments, such as 4 segments S1-S4, according to the nonlinearity of the PA characteristic curve. Each of those nonlinear segments will be assigned more LUT entries than each of those linear segments to combat the PA nonlinear distortion. Although it is still uniform spacing within each segment, this technique as a whole enjoys the advantage of non-uniform LUT spacing. The piecewise-uniform spacing technique also requires prior knowledge of the PA characteristic so as to divide the PA input amplitude range into segments of different linearities. The piecewise-uniform spacing technique focuses on the subject of PA characteristics and ignores how input signal statistics may influence the IMD performance of a PA linearization technique.
Because of the aforementioned problems, it is imperative to provide a technique to dynamically calculate an unconditionally-optimum LUT spacing which minimizes the overall average IMD power.
SUMMARY OF THE INVENTION
The present invention has been made to overcome the aforementioned drawback of conventional gain-based DAPD-LUT techniques for PA linearization. The primary object of the present invention is to provide an apparatus and a method of dynamically adapting the LUT spacing for linearizing a PA. Wherein the LUT spacing is decreased for the amplitude ranges with higher signal probability densities so that the overall average of IMD power is minimized.
The present invention is to provide an apparatus and a method to optimize the LUT spacing for PAs without prior knowledge of system state information (SSI), i.e. an SSI-learning low-complexity technique to optimize the LUT spacing for a DAPD-LUT technique.
The present invention is to provide an apparatus and a method capable of online adapting the LUT spacing for PAs with various nonlinear characteristics, for input signals with various statistics, and for wireless environments with various time-varying properties.
The present invention of an apparatus of dynamically adapting the LUT spacing for linearizing a PA includes an index mapper, a spacing adaptor, and a size-N LUT dividing a whole unsaturated PA input amplitude range into N bins. The apparatus linearizes the PA to produce an amplified output signal in response to a predistorted input derived from an input modulated signal.
According to the present invention, the IMD power associated with each LUT entry is in terms of variables other than the IBO, the PA characteristics and the PDF of the modulated input signal. The concerned LUT spacing problem becomes an optimization problem to minimize the total IMD power at the PA output. The existence of an optimum solution to the optimization problem is also guaranteed. The new LUT spacing balances the IMD power at the PA output corresponding to each bin, so that the total IMD power at the PA output is minimized.
The present invention describes an iterative procedure to approach a stationary solution which is likely to be the optimum solution. After that, it adaptively updates the index mapper through the iterative procedure.
Experimental results demonstrate the feasibility and robustness of the present invention with its performance close to that of the unconditionally-optimum technique and with its computational complexity much lower than that of the conditionally-optimum spacing technique.
The foregoing and other objects, features, aspects and advantages of the present invention will become better understood from a careful reading of a detailed description provided herein below with appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the linearization of a digital predistorter.
FIG. 2 is a block diagram illustrating a conventional DAPD-LUT technique with a uniform LUT spacing.
FIG. 3 is a block diagram illustrating a conventional gain-based DAPD-LUT technique with an optimum non-uniform LUT spacing referred to as the conditionally-optimum spacing.
FIG. 4 is another conventional gain-based DAPD-LUT technique with a non-uniform LUT spacing referred to as the piecewise-uniform spacing.
FIG. 5 shows a baseband-equivalent schematic view of a first embodiment of the apparatus according to the present invention.
FIG. 6 is a block diagram of the index mapper shown in FIG. 5 .
FIG. 7 is a flowchart illustrating the iterative procedure.
FIG. 8 shows the power spectral density performance comparison among several DAPD-LUT techniques with various LUT spacings in the system scenario with IBO=−10 dB.
FIG. 9 shows the normalized IMD power of several DAPD-LUT techniques with various LUT spacings in system scenarios with varying IBOs and different PAs.
FIG. 10 shows the normalized IMD power at the PA output of several DAPD-LUT techniques with various LUT spacings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Without prior knowledge of the system state information (SSI), the present invention provides an apparatus of SSI-learning and low complexity to optimize the LUT spacing for PAs. FIG. 5 shows a baseband-equivalent schematic view of the apparatus according to the present invention. Referring to FIG. 5 , the apparatus comprises an index mapper 501 , a spacing adaptor 503 , and a size-N LUT 505 containing N entries. The apparatus linearizes a PA 521 to produce an amplified output signal in response to a predistorted input derived from an input modulated signal v m .
An amplitude unit 520 derives the absolute amplitude of the input modulated signal v m . The size-N LUT 505 divides the unsaturated PA input amplitude range into N bins, each predistorted by an entry of the LUT 505 . The LUT 505 is indexed by an input amplitude r m of modulated signal via the index mapper 501 to implement an unconditionally non-uniform LUT spacing. Because the characteristics of a PA may vary with temperature and may be affected by aging, an adaptive algorithm online updates the LUT value. The spacing adaptor 503 online adapts the LUT spacing. Each LUT entry corresponds to an input amplitude r m of modulated signal. The adapted LUT spacing balances the IMD power at the PA output corresponding to each bin, so that the total IMD power at the PA output is minimized.
FIG. 6 is a block diagram of the index mapper shown in FIG. 5 . As shown in FIG. 6 , if the update indicator ω set to be 1, the spacing adaptor 503 is running. When the spacing adaptor 503 provides the index mapper 501 with a new set of bin boundary {b i }, the index mapper 501 generates an index of the LUT 505 to indicate a selected entry of LUT 505 . While the LUT 505 is indexed by an input amplitude r m via the index mapper 501 to implement the unconditionally non-uniform LUT spacing. Thereby, each LUT entry corresponds to an input amplitude r m .
In order to make the LUT spacing of the present invention unconditionally-optimized, the present invention expresses the IMD power associated with each LUT entry in terms of variables other than the IBO, the PA characteristics and the PDF of the modulated input signal. In other words, the concerned LUT spacing problem becomes an optimization problem to minimize the total IMD power at the PA output. The followings describe the IMD power derivation according to the present invention to guarantee the existence of the optimum solution under some practical scenarios.
Without loss of generality, the present invention assume that (1) the modulated input signal v m is real and (2) the PA has only amplitude-modulated amplitude-distortion (AM/AM) nonlinear distortion to proceed with the IMD power derivation. After that, the derivation is extended to a general scenario.
Since the number of the LUT entries is finite, N≠∞, so the transfer function of the PD is only piecewise continuous. The PD transfer function of the i th bin is defined as F i (r m,i ), where r m,i =r mo,i +δr m,i is an input signal amplitude near the amplitude midpoint r mo,i of the i th bin. With r m,i as the input amplitude of the i th bin, the PA output amplitude error associated with the i th LUT entry is derived as
e i =G ( F o ( r m,i ))− G ( F i (r m,i ))≈ F i ·G′ ( F i ( r mo,i )),
where F o (r mo,i ) is the ideal PD transfer function of the i th bin, δF i =r m,i ·δ|f i |≈r mo,i ·|f o (r mo,i )|′·δr m,i is the LUT approximation error of the PD output amplitude, δ|f i | is the PD gain error of the i th LUT entry value, f o (r mo,i ) is defined as the LUT value of r mo,i in the i th bin, |f o (r mo,i )|′ is the derivative of |f o (r mo,i )| with respect to r m,i , and G′(F i (r mo,i )) is the slope of the tangent to the G curve, where the G curve is the transfer function of a PA. Note that we have
G ′ ( F i ( r mo , i ) ) = ⅆ ⅆ F i ( r m , i ) G ( F i ( r m , i ) ) ❘ F i ( r m , i ) = F i ( r mo , i ) = ( ⅆ ⅆ r m , i F i ( r m , i ) ❘ r m , i = r mo , i ) - 1 , where F i ′ ( r mo , i ) = ⅆ ⅆ r m , i F i ( r m , i ) ❘ r m , i = r mo , i = f o ( r mo , i ) + r mo , i · Re ( f o * ( r mo , i ) · f o ′ ( r mo , i ) ) f o ( r mo , i ) ,
f′ o (r mo,i ) is the derivative of f o (r mo,i ) with respect to r m,i , (·)* is the complex conjugate operation, and Re(·) denotes the real part of the enclosed argument.
For a small bin, it is reasonable to expect that δr m,i is uniformly distributed over the entire bin width. The IMD power associated with the i th LUT entry governing a bin of width d i can further be expressed as
1
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To generalize the derivation above, the present invention now considers the amplitude-modulated phase-distortion (AM/PM) effect of the PA having a complex modulated input signal v m . With a similar derivation, the phase error associated with the i th LUT entry at the PA output is expressed as
e ϕ , i ≈ ( ⅆ ⅆ r m , i arg ( f o ( r m , i ) ) ❘ r m , i = r mo , i ) · δ r m , i - r mo , i · f o ( r mo , i ) ′ · δ r m , i · ( ⅆ ⅆ r m , i arg ( f o ( r m , i ) ) ❘ r m , i = r mo , i ) = [ arg ( f 0 ( r mo , i ) ) ] ′ · ( 1 - r mo , i · f o ( r mo , i ) ′ ) · δ r m , i ,
where |f o (r mo,i )| and arg(f o (r mo,i )) respectively denote the amplitude and the phase of f o (r mo,i ), and |f o (r mo,i )|′ and [arg(f o (r mo,i ))]′ respectively denote the derivative of |f o (r mo,i )| and arg(f o (r mo,i )) with respect to r m,i .
Since the amplitude error e i and the phase error e φ,i are orthogonal in the polar coordinate, the IMD power associated with the i th LUT entry can thus be extended
to
1
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The concerned LUT spacing problem becomes an optimization problem to minimize the total IMD power at the PA output as
{ β i } = arg min { d i } P ae = arg min { d i } ∑ i = 1 N η i · d i 2 ,
where η i = [ ( f o ( r mo , i ) ′ F i ′ ( r mo , i ) ) 2 + ( [ arg ( f o ( r mo , i ) ) ] ′ · ( 1 - r mo , i · f o ( r mo , i ) ′ ) ) 2 ] · r mo , i 2 · p i 12 ,
and p i is the probability mass function (PMF) of r m in the i th bin.
Next, the present invention describes an iterative procedure to approach a stationary solution which is likely to be the optimum solution. After that, the present invention further adaptively updates the index mapper through the iterative procedure.
FIG. 7 is a flowchart illustrating the iterative procedure. Referring to FIG. 7 , the iterative procedure starts with the initialization of the bin boundaries and the iteration index, it then assigns the midpoint of each bin, as illustrated in step 701 . In step 702 , a long-term histogram for a plurality of modulated input signals is estimated. First, the modulated input signals are processed for a current iteration k, and a short-term histogram {ĥ i (k) } is summarized. A long-term histogram {h i (k) } is then approximated through the mean of the short-term histogram. However the present invention further replaces the PMF {p i } by a long-term histogram {h i }, the optimization problem becomes truly unconditional. According to the stationary solution, the bin width {d i }, for all i, are updated, as shown in step 703 . After the LUT spacing is updated, the current iteration waits for a time period until all the LUT entry values have been renewed, as shown in step 704 . If all the LUT entry values have been renewed, the update indicator is set to be 1. Otherwise the update indicator is set to be 0. The update indicator ω points out the LUT entry values are or are not updated. The renewed values are used for the next iteration. Finally, a step of check convergence with a convergence indicator ρ is taken, as in step 705 . If the LUT spacing difference
∑ i = 1 N d i ( k ) - d i ( k - 1 )
between the current iteration and the previous iteration is smaller than a predetermined threshold ε., then the convergence indicator is set to be 1; otherwise the convergence indicator is set to be 0. The convergence indicator ρ serves as a quality indicator of the DAPD-LUT technique.
Therefore, in order to prepare for the next iteration, the followings must be done, i e. updating the bin boundaries by
b i ( k + 1 ) = b i - 1 ( k + 1 ) + d i ( k ) ,
reassigning the bin midpoints by
r mo , i ( k ) = 1 2 ( b i ( k ) + b i - 1 ( k ) ) ,
increasing the iteration index by 1, and going back to step 702 . Please be noted that, even when the convergence indicator ρ equals to 1, the iteration of the procedure will continue so as to online adapt the LUT spacing to the variations of all kinds of system conditions.
According to the present invention, in the step 701 , the initial values of the bin boundaries {b i (k) } may be set as
b 0 ( 1 ) = 0 and b i ( 1 ) = i N ,
where i is the bin index and the superscript (·) (k) denotes the iteration index. After the iteration index k is set to 1, the midpoint of each bin is assigned as
r mo , i ( k ) = 1 2 ( b i ( k ) + b i - 1 ( k ) ) .
In the step 702 , the long-term histogram is estimated by h i (k) =λ·h i (k−1) +(1−λ)·ĥ i (k) , where the short-term histogram {ĥ i (k) } is averaged, λ is a forgetting factor, 0<λ≦1, and
h i ( 0 ) = 1 N .
In the step 703 , the bin widths {d i } for k th iteration is updated by
d i ( k ) = ξ ( k ) η i ( k ) ,
where η i ( k ) = [ ( f o ( r mo , i ) ′ F i ′ ( r mo , i ) ) 2 + ( [ arg ( f o ( r mo , i ) ) ] ′ · ( 1 - r mo , i · f o ( r mo , i ) ′ ) ) 2 ] · r mo , i 2 · h i ( k ) 12 ,
ξ ( k ) = ( ∑ i = 1 N ( η i ( k ) ) - 1 ) - 1
is a normalization constant, f o (r mo,i ) denotes the LUT value of r mo,i in the i th bin, F i (r mo,i ) denotes the PD transfer function of the i th bin, F′ i (r mo,i ) denotes the derivative of F i (r mo,i ) with respect to r m,i , |f o (r mo,i )| and arg(f o (r mo,i )) respectively denote the amplitude and the phase of f o (r mo,i ), and |f o (r mo,i )|′ and [arg(f o (r mo,i ))]′ respectively denote the derivative of |f o (r mo,i )| and arg(f o (r mo,i )) with respect to r m,i .
FIG. 8 shows the power spectral density (PSD) performance comparison among several DAPD-LUT techniques with various LUT spacings in the system scenario with IBO=−10 dB, wherein the PSD performance is in terms of the normalized PSD of the PA output signal. As shown in FIG. 8 , the dynamically-optimum of the present invention outperforms the other techniques with large gaps and approaches the unconditionally-optimum technique with a small gap.
Two simulation experiments are further conducted to evaluate the present invention. The first experiment tests its feasibility and compares the IMD performance among several conventional DAPD-LUT techniques with various LUT spacings. The second experiment tests the robustness of the present invention in a time-varying wireless system.
In the first experiment, two conditions of the IBO and the PA characteristics conditions in the system scenario are relaxed. The normalized IMD powers of several DAPD-LUT techniques with various LUT spacings are shown in FIG. 9 . The two solid curves denote the IMD performance in the system scenario with PA # 1 . The three dashed curves denote the IMD performance in the system scenario with PA # 2 . Since the nonlinearity of PA # 2 is worse than that of PA # 1 , the unconditionally-optimum scheme in the system scenario with PA # 2 performs worse than that with PA # 1 . Nevertheless, the performance of the dynamically-optimum technique of the present invention still approaches that of the unconditionally-optimum technique regardless of the PA characteristics.
On the other hand, if the conditionally-optimum technique is optimized for IBO=−10 dB and PA # 1 in system scenarios with varying IBOs and with PA # 2 , as shown as the “(−10 dB, PA # 1 ) Optimum with PA # 2 ” curve in FIG. 9 , the performance degradation is significant. Comparing point A and point B in FIG. 9 , it can be observed that there is a 6-dB performance degradation of the conditionally-optimum technique with only the mismatch of the PA characteristics.
In the second experiment, the robustness of the dynamically-optimum technique of the present invention in a highly volatile system scenario is tested. The learning curve of the dynamically-optimum technique of the present invention is shown in FIG. 10 in a time-varying system scenario with (1) IBO=−20 dB, PA # 1 , and the non-uniform OFDM input at the beginning, (2) the IBO jumping from −20 dB to −10 dB at the 50 th iteration, (3) PA # 1 being replaced by PA # 2 at the 100 th iteration, and (4) the non-uniform OFDM input being replaced by the uniform input at the 150 th iteration. The horizontal axis represents the number of iteration of the iterative procedure as stated above. The vertical axis represents the normalized IMD power at the PA output.
As can be seen from FIG. 10 , only the dynamically-optimum technique of the present invention can adapt itself to the variations of the system conditions. In other words, the performance of the dynamically-optimum technique of the present invention ties itself to the performance of the unconditionally-optimum technique with some transitional performance adaptation, while the performance of all the other DAPD-LUT techniques fluctuates dramatically.
In summary, the present invention provides a dynamically optimized non-uniform LUT spacing for the DAPD-LUT technique to linearize a PA, which has the advantages of being adaptive to all kinds of signal source going through all kinds of PA, being adaptive to time-variation of the wireless environments, low computational complexity, and reaching unconditionally-optimum performance.
Although the present invention has been described with reference to the preferred embodiments, it will be understood that the invention is not limited to the details described thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims. | A digital adaptive predistorter look up table (DAPD-LUT) technique dynamically adapts a look up table (LUT) an LUT spacing for linearizing a power amplifier (PA). It optimizes the LUT spacing for the PA without prior knowledge of system state information. A size-N LUT divides a whole unsaturated PA input amplitude range into N bins, each predistorted by an entry of the LUT. The LUT is indexed by an input amplitude of a modulated signal via an index mapper to implement an unconditionally non-uniform LUT spacing. A spacing adaptor online interactively adapts the LUT spacing. The adapted LUT spacing balances the inter-modulation distortion (IMD) power at the PA output corresponding to each bin, so that the total IMD power at the PA output is minimized. This dynamically-optimum technique is practical, robust, and with low complexity. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an improved method and apparatus for cleaning the fluid flow path in a conduit. The present invention may be utilized to clean drain lines in any application, whether commercial or residential, and is not necessarily limited to sewage systems. More particularly, the present invention relates to an apparatus and method for clearing a build-up in a trap within a drainage system which may be impeding the flow of fluid from the system discharge. The present invention has an embodiment wherein the dynamic for clearing the flow path is supplied by angular arrangement and orientation of the inlet and outlet piping legs of the apparatus.
[0002] In most drainage systems, traps are provided to catch or collect materials passing through the system. In commercial and residential plumbing systems, traps are used to capture items falling into the drain, so that they do not pass directly through the drain line and into the main sewer system. They are also intended to block sewer gas bleed back into the building. However, the traps often accumulate excessive amounts of debris and build-up blocking the drainage flow through the system.
[0003] Existing devices are cumbersome and ineffective. Many of these “solutions” create other problems for the user, including actually interfering with the drainage flow when not in operation. Any device which restricts the full volume flow through the bight of a trap when not in use potentially will cause more problem than it solves.
[0004] The present invention provides embodiments to maintain a clean flow passage. In one embodiment, the design of the inlet and outlet passages provides unique flow characteristics so that the device has a self cleaning action. The design of the approach angle of the device and the exit angle of the outlet portion of the device is critical to the self cleaning nature of a trap. A typical trap system is generally U-shaped and has inlet and outlet piping that is substantially vertical in relation to the bight of the trap body. Fluid flowing into the conventional trap tends to migrate to the inside center of the pipe. When this happens, the inflowing fluid loses its ability to carry solids effectively. Furthermore, when the inflowing fluid reaches the substantially horizontal section of the trap or the bottom on the U-shape, the inflowing fluid has lost much of its energy and thus allows solids to remain in the bottom or nadir, of the trap. The present invention maximized the solids carrying ability of the inflowing and outflowing fluid. The inlet leg of one embodiment is designed to redirect the flow of the inflowing fluid and, thus, cause solids in the flow path turbulently to mix with the fluid so that solids may be removed efficiently as the fluid and solids exit the trap device.
[0005] A further feature of the present design is the recessed trap area at the nadir of the trap. Since the incoming fluid flow has been directed by the angle of the inlet leg, an area of turbulence near the bottom of the trap is created that tends to “float” or maintain the dispersion of the solids so that the solids may be easily discharged through the angular outlet leg portion of the device. It should be further understood that the shape of the flow path is important to the removal of the solids. The present design provides a round or oval cross-section of the entire fluid flow path in the trap, which creates maximum flow efficiency. One trap design, as described in U.S. Pat. No. 6,385,799, utilizes parallel sides and a somewhat rectangular cross-section. Those skilled in the art will understand that parallel sided conduits create “dead” areas of lost flow energy which result in less turbulence and inefficient solids removal from the trap.
[0006] In yet another embodiment, the user is able to rotate a cleaning or object retrieval member through the trap assembly bight without removing the trap body from connected plumbing and to position the cleaning or object retrieval member such that the full volume flow through the bight diameter is not restricted when the member is not being rotated through the flow path. The present invention may be manually operated or attached to a sensor system having a mechanism to periodically rotate the cleaning member either based simply on a selected time interval or dependent upon pressure or flow rate characteristics within the drain system. Additionally, the present invention provides an embodiment wherein the cleaning member rotates on a common journal with a fluid-driven power wheel or electric motor.
[0007] Another unique feature of the present invention is that the device is transparent or translucent to allow the user to observe the condition of the trap to observe when cleaning may be required. This transparency or translucency also allows the user to observe an object dropped into the drain so it can be retrieved or otherwise removed.
[0008] Another unique feature of the present invention provides for the application of a hydrophobic material which reduces the surface tension of the internal conduit which reduces the friction between the conduit wall and the fluid which improves its solids carrying efficiency.
[0009] Another unique feature of the present invention provides for the application of an antibacterial material which will prevent the growing of bacteria in the trap area which can impede the fluid flow.
[0010] Further yet, it has been found that the cleaning of the flow path may be facilitated by disposing a fluid jet adjacent the nadir of the flow path. Several embodiments of this “jet trap” are disclosed herein.
[0011] While the present invention is described and illustrated in a preferred embodiment within a plumbing/sewer environment, it will be understood that the present invention could be adapted for use in industrial situations where product in a pipeline periodically may need to be flushed or wiped from the pipeline. In such situations, the present invention may not function as a trap, but rather as an inline cleaning or clearing apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 illustrates a prior art, well-known drain trap which may be connected to a sink and a drain line.
[0013] FIG. 2 shows a side elevation view of one embodiment of the present invention as it would be connected to a fluid inlet feed line and an outlet drain line.
[0014] FIG. 3 is a side elevation view of one embodiment of the present invention with a rotation member at a first position inside the housing assembly. The rotation member is shown in broken lines in a next position moving toward an object or debris in the nadir of the trap.
[0015] FIG. 4 illustrates a side elevation view of the embodiment of FIG. 3 , wherein the object or debris has been scooped onto the rotation member and is being retrieved through the inlet using a hook or appropriate tool.
[0016] FIG. 5 shows the side elevation view of the embodiment of FIG. 3 , wherein the debris is being dispersed by the inflowing fluid from the inlet leg of the device. The debris is flowing out the outlet leg.
[0017] FIG. 6 shows one embodiment of the present invention with a sensing system connected to rotate the rotation member as appropriate. Further illustrated are weir distances maintained by the structural arrangement of the elements of the embodiment.
[0018] FIG. 7 is an exploded perspective of one embodiment of the present invention showing the two sections of the housing assembly, the rotation member, a one-direction ratchet mechanism, and a rotation knob.
[0019] FIG. 8 is a front elevation in cross-section of one embodiment of the present invention having an extended common journal which may be connected to a fluid turbine or electric motor to drive the rotation member.
[0020] FIG. 9 is an illustration of a plumbing configuration for one embodiment of the present invention having a fluid jet mechanism.
[0021] FIG. 10 shows a partial cross-sectional view of a rotatable fluid jet mechanism disposed within the housing assembly.
[0022] FIG. 11 shows a partial cross-sectional view of an embodiment of the present invention having a non-rotatable fluid jet mechanism.
[0023] FIG. 12 illustrates in side elevation cross-section a fluid jet journal of one embodiment of the present invention.
[0024] FIG. 13 illustrates an end view cross-section of the jet journal of FIG. 12 .
[0025] FIG. 14 is a side elevation view of one embodiment of the fluid jet mechanism of the present invention.
[0026] FIG. 15 shows a side elevation view of yet another of the fluid jet mechanism of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] FIG. 1 illustrates a typical (prior art) drain trap 10 which attaches to a sink and drain line (not shown). The trap 10 has a U-shaped configuration with a generally vertical inlet 12 and outlet 14 piping leg sections each having a longitudinal axis L 1 and L 2 extending therethrough. Between the vertical legs 12 and 14 , in the bight 16 of the trap is a region H 1 , where there is a low energy of flow of water through the trap. The water flow WF into the bight from inlet leg 12 is focused in the center section of the leg and when it reaches the bight considerable flow energy has been lost. Thus in the conventional trap, debris falling to the nadir of the bight does not experience much agitation or turbulence. This is a reason for the development of clogs and build-ups which obstruct the flow of fluid through the trap.
[0028] A basic embodiment 20 of the present invention is shown in FIG. 2 in a side elevation view attached to an inlet feed line 21 and an outlet drain line 23 . It should be understood by one of ordinary skill in the art that standard piping and conduit structures may be used to form the present invention. Circular or oval tubing may be utilized. A split housing assembly 22 may be made of rugged plastics or other suitable materials. The housing assembly may be transparent or translucent to improve the visibility of the conditions inside the housing assembly 22 . ( FIG. 7 illustrates the two halves 22 A and 22 B of the housing 22 .)
[0029] The apparatus 20 is also provided with a tubular inlet portion 24 , a tubular outlet portion 26 , and a bight portion 28 connecting the inlet portion and the outlet portion thus forming a fluid flow path through the apparatus 20 . An inlet connector member 30 has a standard threaded coupling 32 at a first end for attachment to a complementary coupling on the inlet feed line (not shown). The inlet connector member has a generally vertical orientation when attached to the inlet feed line and a longitudinal vertical axis L 3 extends through the central tubular section of the inlet connector member. This short vertical connector member 30 enables the present invention to easily replace existing conventional traps. Member 30 allows for proper plumbing alignment and for the insertion of the inlet feed line into the connector member 30 for proper pipefitting.
[0030] Unlike the conventional trap 10 , apparatus 20 has a sloped inlet leg portion 34 extending from a first end 36 at the connector member 30 to a second end 38 at the bight portion 28 . The inlet leg portion 34 is tubular with a circular or oval cross-section. A longitudinal axis 4 extends through the central part of the inlet leg portion at an inclined or sloped angle A. While improved operation may be achieved with low approach angles (greater than approximately 5°), it is believed that significant improvement is obtained with an inclined or sloped angle A in the range of from approximately 15° to a range of approximately 35° from the vertical longitudinal axis L 3 of the inlet connector member 30 . Maximum efficiency may be achieved when angle A is approximately 20°.
[0031] Apparatus 20 further has a unique sloped outlet leg portion 40 extending from a first end 41 at an outlet connector member 33 . The outlet connector member 33 is similar to the inlet connector member 30 and has a thread coupling 35 for attachment to a complementary coupling on the outlet drain line (not shown). The outlet connector member 33 has a generally vertical orientation when attached to the outlet drain line and a longitudinal vertical axis L 5 extends through the central tubular section of the outlet connector member 33 . As with the inlet connector member 30 , the outlet connector member 33 allows for plumbing alignment and for insertion of the outlet drain line into the connector member 33 for proper pipefitting.
[0032] Outlet leg portion 40 is tubular with a circular or oval cross-section. A longitudinal axis L 6 extends through the central part of the outlet leg portion at an inclined or sloped angle B. Again, there is improvement even when angle B is low (greater than about 5°). Significant improvement may be achieved with angle B in the range of from approximately 15° to a range of approximately 35° from the vertical longitudinal axis L 5 of the outlet connector member 33 . Maximum efficiency may be achieved when angle B is approximately 20°.
[0033] This simple, but unique, angular configuration and arrangement of the inlet and outlet leg portions of the apparatus 20 provides for enhanced flow dynamics within the housing and especially the bight, thereby reducing buildups in the flow path of the device.
[0034] Turning to FIGS. 3 and 7 , one embodiment of the present invention includes a rotation member 54 within the chamber 46 of the housing assembly Member 54 moves an object or debris 61 from the bight up into the fluid flow path in inlet leg portion 34 . As would be understood by one of ordinary skill in the art, one end 57 of the journal 56 extends through a journal opening in the side of first housing half 22 A. The opening 62 is provided with journal bearing shoulder an appropriate seals to support the journal 56 and prevent leakage around the journal. A rotation hub or handle 60 may be affixed to the journal to assist the user in rotating the member 54 . The opposite end 59 of the journal 56 is appropriately supported and sealed in a support shaft bearing shoulder 68 in the second housing half 22 B.
[0035] It should be further understood that the end 59 of journal 56 could be extended to project through the housing wall of half 22 B, the housing wall provided with appropriate seals and bearings so as to enable the rotation member 54 to be rotated or driven on either side of the housing assembly 22 .
[0036] The rotation member 54 has a plurality of spaced apart teeth 70 extending radially from the journal 56 . Teeth 70 shovel, scrape or scoop debris or buildup from the flow path in the bight of the apparatus. A paddle member 80 is also provided on the rotation member 54 . Paddle 80 may be rigid or flexible as it extends radially from the journal 56 . The paddle trails the teeth 70 and, in operation, may wipe the inner bight walls during rotation moving loosened sludge or buildup out of the chamber 46 and into the inlet leg portion 34 . FIG. 3 illustrates the movement of rotation member 54 , teeth 70 , and paddle 80 from a first position (out of the flow path) to a position near an object or debris 61 . The rotation of member 54 is one-direction movement (shown in FIG. 3 as clockwise) from the outlet portion 26 toward the inlet portion 24 . The direction of rotation ensures that large objects or undispersed debris are not inadvertently urged toward the outlet drain line thereby potentially causing a blockage or plug which is outside of the reach or range of the rotation member. By moving debris toward the inlet portion, the fluid flow energy breaks up the debris into small segments allowing it to be more easily flushed from the apparatus.
[0037] FIG. 4 shows a situation where the object or debris 61 has been scooped and moved to another position within the apparatus 20 at the inlet leg portion 34 . FIG. 4 illustrates the use of an appropriate tool 90 to retrieve the object or debris by fishing downwardly through the inlet feed line into the inlet leg portion 34 .
[0038] As previously discussed, the one-direction rotation of member 54 moves debris into the inlet leg portion 34 exposing the debris to the high energy fluid flow HF created by the angular configuration of the leg portions 34 and 40 . FIG. 5 shows the debris dispersed as smaller segments 61 a . Segments 61 are moved by the turbulence generated in the fluid flow path. There is a reduced likelihood of large clumps of debris moving outside the reach or range of the member 54 . If a large clump is presented, it may be fished out of the path as shown in FIG. 4 . Once the object or debris is removed from the flow path, rotation member 54 is further rotated (clockwise) to the start or rest position shown in FIG. 3 .
[0039] One-directional rotation is provided by the use of a ratchet mechanism illustrated in FIG. 7 . Although a number of alternative mechanisms may be used, such as slip clutches and engaging dents, FIG. 7 illustrates a simple two-part ratchet 72 . A number of projections 72 may be formed into the outer surface of housing half 22 A which cooperates with ratchet teeth 72 b on ratchet hub 73 . Projection 72 may be on a separate plate affixed to the housing. Teeth 72 b are sloped on one side and generally straight on the opposite side (as is well-known in the art) to allow the ratchet hub 73 to easily rotate in one direction (here clockwise) and restricting rotation in the counter direction.
[0040] Rotation of member 54 may be accomplished manually or automatically. FIG. 6 shows a schematic diagram of a sensor system connected to the present invention to activate a rotation device RD connected to the rotation member 54 within the housing. FIG. 6 shows two sensors in the system which causes the member 54 to rotate through the path described above. The first is a pressure or flow sensing probe PS inserted into the inlet portion 24 of the housing 22 . The probe senses when a predetermined pressure or flow rate has been reached (indicating a restriction in fluid flow through the apparatus 20 ) and activates a motor or other driver RD through a pressure transducer PT. In combination, or in the alternative, a timer T may be attached to the rotation device (motor/driver) RD to periodically activate the motor/driver to rotate the member 54 within the chamber 46 . The timer system has the advantage of activating the operation of the apparatus before large buildups are accumulated. It should be understood that the operation of the apparatus may be achieved manually by using the hub 60 itself to rotate the journal.
[0041] FIG. 6 also illustrates that the apparatus 20 of the present invention meets generally accepted plumbing codes. For example, a uniform code may state that each fixture trap shall have a water seal of not less than two (2) inches (51 mm) and not more than four (4) inches (102 mm) except where a deeper seat is found necessary by the authority having jurisdiction for special conditions or for special designs relating to handicapped accessible fixtures. In the present invention, as shown in FIG. 6 , two locations must be taken into account when meeting the requirements of such uniform plumbing codes:
[0042] a) Weir 1 (W 1 ) distance D: must be maintained to provide the minimum of 2 inches of water seal depth should the paddle 80 not seal in the upper chamber portion 46 a or if the paddle is “parked” in a position that does not effect a seal in the upper chamber portion 46 a;
[0043] b) Weir 2 (W 2 ) distance D 2 must be maintained to provide a maximum of 4 inches of water seal depth should the paddle 80 seal in the upper chamber portion 46 a either intentionally with a seal such as a gasket or unintentionally by buildup of debris between the paddle 80 and the housing wall. Thus, unlike some prior art devices, the present invention meets the uniform codes.
[0044] FIG. 8 illustrates yet another embodiment of the present invention 230 in cross-section. The housing 232 for the rotation member 254 is adapted to include a power housing section 233 . In FIG. 8 , the plastic housing halves are molded with the power housing section integral with the cleaning member housing section. The axle or rotation journal 256 is extended to include a turbine support journal portion 257 on which is secured a turbine or power wheel member 259 . The extended journal is provided with appropriate 8 support bearing 290 . the power housing section 233 is provided with an inlet portion 261 and an outlet port 263 . A driving fluid (liquid or gaseous) may be injected into inlet port 261 into power chamber 265 causing the turbine wheel 259 to rotate as the driving fluid is discharged through outlet port 263 . As the wheel 259 rotates, the journal turbine 257 rotates rotating the axle or rotation journal 256 and the rotation member 254 . One of ordinary skill in the art will understand the construction of a turbine or power wheel 259 as having fins or blades 280 extending radially from the wheel body 282 and positioned to convert the incoming energy from the driving fluid F to rotational energy at the turbine journal 257 .
[0045] In the embodiment of FIG. 8 , an alternative driver could be a motor M appropriated coupled to the journal 257 . In many applications of the FIG. 8 embodiment, the driving fluid is water which is flowing through the power housing 233 , out of outlet port 263 , and to a tub or shower. The drain from the tub or shower would have its drain line attached to the inlet feed line of the housing. Thus, it may only be appropriate to rotate the cleaning member when the tub/shower is being utilized and water is draining from the tub/shower. In such an application, the water being used for the tub/shower is the same water which is driving the turbine wheel and rotating the cleaning member.
[0046] It has been further found that the rotation member inside the housing may be a fluid injection member (or jet) disposed adjacent the nadir of the bight portion. FIGS. 9-15 illustrate various jet designs.
[0047] FIG. 9 shows a plumbing configuration for one embodiment of the jet mechanism of the present invention. The jet-trap mechanism 100 is connected between the sink drain 102 and the drain line 104 by suitable couplings 103 and 105 . The jet-trap housing assembly 122 contains and supports a jet shaft 106 . Shaft 106 may be rotatable or non-rotatable as discussed below in relation to FIGS. 10-13 . A fluid (typically water; but in some applications, it may be another liquid or a gas) is provided to the shaft 106 which injects the fluid into the housing 122 . FIG. 9 shows the shaft being supplied water from the cold supply line 108 , but, again, hot water supply line 110 could be utilized. If potable water is supplied, a check valve or back flow valve 112 must be provide in accordance with uniform codes.
[0048] A jet-trap water feed line and valve 114 is taken off the supply feed and directed to the jet-trap control valve 116 . From control valve 116 , the water enters the shaft 106 in housing 122 through jet-trap supply line 118 . As will be described in more detail below, the shaft 106 primarily injects fluid into the bight area from the direction of outlet side of the mechanism 100 . This ensures that the excess supplied fluid volume may drain out the outlet side while unclogging is attempted.
[0049] FIG. 10 illustrates an elevation view of an embodiment of the jet design of the present invention in cross-section. This embodiment has a rotatable shaft member 106 . One of ordinary skill would understand that the shaft 106 is supported and sealed inside the housing 122 by appropriate bearing housings 120 and seals 121 . The front end 130 a of the shaft 106 a extends through the front bearing housing and is provided with a hub 160 to rotate the shaft 106 . As described above, rotation may be achieved manually or automatically. Jet-trap supply line 118 feeds fluid into shaft inlet 140 which communicates with a central vein or conduit 142 in the shaft 106 . Fluid is discharged into the bight portion of the apparatus 100 from jet ports 144 arranged radially around the shaft 106 . FIG. 13 shows an end cross-sectional view of one arrangement of jet ports 144 .
[0050] The rotatable shaft 106 may be provided with a one-direction ratchet mechanism described above to restrict rotation in the direction from the outlet side to the inlet side of the mechanism 100 .
[0051] Some plumbing codes restrict moving parts in a drain trap. FIG. 11 illustrates a non-rotatable jet shaft 106 . A vein plug 132 is inserted into vein 142 so that a common shaft may be employed in both rotatable and non-rotatable jet shafts.
[0052] A more detailed drawing of the jet shaft 106 is shown in FIG. 12 . The shaft is provided with O-ring grooves 145 . When a rotation device is used to rotate the shaft, thread 147 may be provided in conduit 142 . A splice member 149 is also utilized when necessary.
[0053] Other embodiments of the present invention are shown in FIGS. 14 and 15 . The tubed jet-trap 160 of FIG. 14 is a simple addition to any drain trap to prevent debris from settling in the bight portion. An adaptor connection 171 is attached to the inlet feed line 21 . The adapter has a collar 172 to retain the neck section 173 of a jet tube 174 . Tube 174 extends downwardly through the inlet portion 24 of the trap 160 into the bight portion 28 . Jet ports 176 are provided at the distal end 177 of the tube to inject jet-supply fluid into the bight portion 28 to dislodge and disperse any clog. It will be noted that the jet tube injects fluid at the nadir of the trap near the bottom of any clog or buildup. Thus, injection from the inlet side of the trap is usually effective.
[0054] FIG. 15 illustrates another jet mechanism 180 . Adjacent the bight portion 28 , an inlet nipple 181 is provided in the wall of the housing 22 in fluid communication with the bight portion. Appropriate plumbing is provided to supply jet-supply fluid through the nipple 181 into the housing. A valve 182 (may be rotatable or non-rotatable) is disposed inside the housing and in fluid communication with the nipple 181 . The valve may be constructed similar to the shaft 106 discussed above. A discharge nozzle 183 may be directed at any clog in the bight portion 28 to inject fluid to disperse an obstruction. The nozzle 183 may be rotated to various angular positions to cut and remove debris which may settle in the bight portion. Again, because the fluid is injected at the nadir near the bottom of the clog, the direction of injection may be from the inlet direction to the outlet direction.
[0055] All of the embodiments discussed and described above provide a method for cleaning the fluid flow path between an inlet feed line and outlet drain line. The method includes providing an apparatus having a housing assembly forming a chamber with angular inlet and outlet leg portions having longitudinal axes extending therethrough at a sloped angle greater than about 5°, preferably in the range from approximately 15° to approximately 35°, or more preferably at approximately 20°, from the vertical as described above. The apparatus may be further provided with 1) a rotatable member disposed within the housing rotatable only in a direction from the outlet leg portion to the inlet leg portion or 2) a fluid injection member disposed within the housing adjacent the nadir of a bight portion of the housing. The method further includes the steps of attaching the apparatus in fluid communication with the inlet feed line and the outlet drain line.
[0056] Although the invention has been described with reference to a specific embodiment, this description is not meant to be construed in a limiting sense. On the contrary, various modifications of the disclosed embodiments will become apparent to those skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended claims will cover such modifications, alternatives, and equivalents that fall within the true spirit and scope of the invention. | A conduit cleaning method and apparatus for connection to a fluid inlet feed line and an outlet drain line utilizes a housing assembly having an inlet portion, an outlet portion, and a bight portion. The inlet and outlet portions have sloped leg sections which provide increased fluid flow through the bight to disperse accumulated debris. Rotatable shafts inside the housing accommodate paddles or jets to facilitate in retrieval or dispersal of obstruction. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The application relates to a process for preparing 3,6-dihydro-2H-pyran-2-carboxylic esters via a thermal hetero Diels-Alder reaction from 1,3-dienes and esters of glyoxylic acid.
[0003] 2. Brief Description of the Prior Art
[0004] The hetero Diels-Alder reaction of conjugated dienes with carbonyl compounds is one of the fundamental reactions in organic chemistry. Conjugated dienes can in principle be reacted thermally with glyoxylic esters in a hetero Diels-Alder reaction to give 3,6-dihydro-2H-pyran-2-carboxylic esters.
[0005] J. Org. Chem. USSR, 1970, 6, 411 discloses the reaction of 2,3-dimethyl-1,3-butadiene or isoprene with ethyl glyoxylate in a thermal hetero Diels-Alder reaction to give the corresponding 3,6-dihydro-2H-pyran-2-carboxylic esters. To this end, diene, ethyl glyoxylate and hydroquinone are mixed on the 500 mmol scale and then heated to 130° C. The 3,6-dihydro-2H-pyran-2-carboxylic esters are obtained on this laboratory scale in yields of 40 to 74%.
[0006] According to Tetrahedron 1993, 49, 4639-4650, 10 mmol of ({[(3E)-2-(benzyloxy)-3,5-hexadienyl]oxy}methyl)benzene and other dienes are mixed with butyl glyoxylate and hydroquinone and heated to 130° C. for 18 hours. After workup, cycloadducts are obtained in 60% yield.
[0007] Org. Magn. Res. 1983, 21, 94-107 also discloses the preparation of butyl 3,6-dihydro-2H-pyran-2-carboxylates via a thermal Diels-Alder reaction from 1,3-butadiene and butyl glyoxylate on a small scale.
[0008] More highly substituted, conjugated dienes generally react at relatively low temperatures and in better yields. For example, reactivity and yield increase in the order 1,3-butadiene<2-methyl-1,3-butadiene<2,3-dimethyl-1,3-butadiene.
[0009] In recent times, progress has been made on the route of catalyzed hetero Diels-Alder reactions with glyoxylic esters. The advantage of these methods described, for example, in Tetrahedron Lett. 1998, 39, 1161-1164, J. Chem. Soc., Chem. Commun. 1996, 2373-2374, J. Chem. Soc., Perkin Trans, 1, 1997, 2345-2349 and J. Org. Chem. 1995, 60, 5757-5762 is frequently a relatively low reaction temperature. A disadvantage of the catalyzed syntheses is that expensive (BiCl 3 , Me—Al[(S)-BINOL], Zn(OTf) 2 , and toxic (SnCl 2 , Cu compounds) catalysts which are often difficult to prepare are used which make the process uneconomical. In addition, the removal of the product is distinctly more complicated. For most of these examples, industrial scale reaction is impossible for environmental reasons, since heavy metal wastes (Bi, Sn, Cu) occur.
[0010] J. Org. Chem. 1995, 60, 5757-5762 describes the reaction of glyoxylic esters with conjugated dienes catalyzed by a copper(II)-bisoxazoline complex. In this reaction, isopropyl glyoxylate, for example on the 10 mmol scale, is reacted with 5 to 10 equivalents of 1,3-butadiene in dichloro-methane in the presence of a catalyst which is formed in situ from Cu(OTf) 2 and a chiral oxazolidinone within 5 days to give the corresponding 3,6-dihydro-2H-pyran-2-carboxylic ester. The yield obtained is 55%.
[0011] All of the above-mentioned publications on thermally catalyzed reaction of conjugated dienes with glyoxylic esters to give 3,6-dihydro-2H-pyran-2-carboxylic esters have the common disadvantage that the reaction comprises a procedure which (for the purposes of the present application) is referred to as a batch process. In this batch process, all reaction components, i.e. the diene and the glyoxylate (and also the customarily used stabilizer), are initially combined directly at low temperature and mixed with one another and then brought to the required reaction temperature of generally more than 100° C. by heating. These batch processes are only described for performance on the laboratory scale.
[0012] However, this procedure, in particular in a reaction on a relatively large scale, is highly questionable for safety reasons, since conjugated dienes, especially 1,3-butadiene, tend to thermally polymerize at elevated temperature and the associated adiabatic temperature increase can lead to thermal decomposition through to explosion of the reaction mixtures.
[0013] The strongly exothermic polymerization of 1,3-butadiene sets in, for example, at temperatures above 100° C. with a heat of reaction of about 1350 kJ/kg. Immediately after the polymerization, strongly exothermic decomposition of the polymer occurs from about 295° C. Heat liberated by the decomposition is about 1500 kJ/kg (Odian “Principles of Polymerization” p. 264-Table 3-14.)
[0014] These factors lead to a rise in the rate of reaction and an exponential rise in the heat output. The consequence is an exothermic reaction which can no longer be controlled (known as a runaway reaction). This is a barrier in particular to conversion of these reactions to the industrial scale and therefore to an economical utilization of this synthetic route existing in principle.
[0015] It is therefore an object of the present invention to provide a process for preparing 3,6-dihydro-2H-pyran-2-carboxylic esters via a thermal hetero Diels-Alder reaction from 1,3-dienes which has no inherent safety problem unlike the existing batch processes and therefore facilitates a synthesis on relatively large scales while at the same time obtaining good yields of the desired product.
SUMMARY OF THE INVENTION
[0016] The present application therefore provides a process for preparing 3,6-dihydro-2H-pyran-2-carboxylic esters of the general formula (I)
[0017] where
[0018] R 1 , R 2 , R 3 and R 4 are the same or different and are each H or a straight-chain or branched C 1 -C 7 -alkyl radical,
[0019] R 5 is a straight-chain or branched C 1 -C 7 -alkyl radical, a phenyl radical or a benzyl radical,
[0020] R 6 and R 7 are the same or different and are each H or straight-chain or branched C 1 -C 3 -alkyl or together form a —(CH 2 ) n -alkylene radical where n=1 or 2,
[0021] via a thermal hetero Diels-Alder reaction of 1,3-dienes of the general formula (II)
[0022] where
[0023] R 1 , R 2 , R 3 , R 4 , R 6 and R 7 are each as defined for the general formula (I) with compounds of the general formula (III)
[0024] where
[0025] R 5 is as defined for the general formula (I), characterized in that the process is carried out in the absence of catalysts and stabilizers and the compound of the general formula (III) is initially charged and brought to a temperature of 90-230° C. and the 1,3-diene of the general formula (II) is then added.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The compounds of the general formula (II) used in the process according to the invention are preferably those in which the R 1 , R 2 , R 3 and R 4 radicals are the same or different and are each hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl or n-pentyl. R 6 and R 7 are the same or different and are preferably each hydrogen or methyl.
[0027] Preference is given to the R 1 , R 2 , R 3 and R 4 radicals each being hydrogen and R 6 and R 7 also each being hydrogen. Alternatively, preference is given to one of the R 1 , R 2 , R 3 and R 4 radicals, particular preference to one or two of the R 1 , R 2 , R 3 and R 4 radicals, each being methyl and, at the same time, R 6 and R 7 being the same or different and each being hydrogen or methyl.
[0028] The compounds of the general formula (III) used in the process according to the invention are preferably those in which the R 5 radical is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, phenyl or benzyl. Particular preference is given to R 5 being methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or tert-butyl.
[0029] When R 5 is a phenyl or benzyl radical, it may be mono-, di-, tri-, tetra- or pentasubstituted. Examples of substituents of the phenyl or benzyl radical include C 1 -C 4 -alkyl, preferably CH 3 or C 2 H 5 , halogen, preferably fluorine, chlorine or bromine, nitro, —OC 1 -C 4 -alkyl, preferably —OCH 3 or —OC 2 H 5 , and —COOC 1 -C 4 -alkyl radicals, preferably —COOCH 3 or —COOC 2 H 5 .
[0030] Compared to the prior art, the process according to the invention is notable for its special metering technique. The compound of the general formula (III) is initially charged and brought to the reaction temperature of 90 to 230° C. Only after that is the 1,3-diene of the general formula (II) added. Customarily, the 1,3-diene is added in such a manner that in each reaction mixture there is only a small excess of 1,3-diene.
[0031] Surprisingly, this way of carrying out the process according to the invention allows the presence of expensive, toxic and environmentally damaging heavy metal catalysts to be dispensed with. The use of stabilizers such as hydroquinone, quinone, phenothiazine, picric acid, TBC (p-tert-butylpyrocatechol), TBC (2,6-di-tert-butyl-p-cresol) or 2,6-di-tert-butyl-4-methylphenol is also no longer necessary. According to the prior art, these stabilizers are always used, and in amounts of 0.1 to 5% by weight, based on the 1,3-diene.
[0032] It has proven useful to carry out the process according to the invention in such a manner that the compound of the general formula (III), i.e. the glyoxylic ester, is initially charged as such or dissolved in an inert solvent in the reaction vessel. Examples of useful inert solvents include pentane, cyclohexane, hexane, benzene, toluene, xylenes, petroleum ether, chlorobenzene or dichlorobenzenes.
[0033] Heating is then effected to the reaction temperature in the range from 90 to 230° C., preferably in the range from 100 to 180° C. Depending on the 1,3-diene used, the range from 120 to 160° C. is also particularly preferred. When 1,3-butadiene is used, reaction temperatures up to a maximum of 180° C. have proven useful.
[0034] When low-boiling compounds are used as the reactants in the process according to the invention, i.e. reactants having a boiling point of up to 100° C., in particular 1,3-butadiene, isoprene and 2,3-dimethyl-1,3-butadiene, the reaction vessel used is customarily an autoclave which is pressure-resistant up to at least 25 bar. Once the compound of the general formula (III) has been initially charged, this autoclave is sealed pressure-tight. Depending on the filling level, increasing the temperature to the reaction temperature causes the internal pressure of the closed autoclave to rise to from 2 to 10 bar. For safety reasons, a maximum of 80% of the nominal reactor capacity is customarily filled. In contrast, when exclusively relatively high-boiling reactants are used in the process according to the invention, stirred tanks may also be used: when the boiling points of the reactants are above 100° C., these stirred tanks are used in pressure-tight sealed form. When reactants having boiling points above 200° C. or above the reaction temperature are used, operation may also be effected using an open stirred tank.
[0035] Once the reaction temperature is reached, the 1,3-diene of the general formula (II) is then added to the reaction vessel in an amount of 1.0 to 3.0 equivalents, preferably 1.3 to 1.5 equivalents, based on the compound of the general formula (III). When gaseous 1,3-dienes such as 1,3-butadiene are used, they are customarily added from a pressurized tank against the internal pressure which has arisen in the reaction vessel by injecting it in either by means of nitrogen or by means of a metering pump.
[0036] The metering time for the addition of the 1,3-diene of the general formula (II) is 3 to 36 hours. The metering time used in each case depends on the 1,3-diene chosen and also on the reaction temperature. In the case of a reaction temperature in the range from 150-180° C., a reaction time of 16 to 6 hours has proven useful. This is suitably followed by a post-reaction of 3 to 24 hours at the above mentioned reaction temperature. Customarily, there is no stirring in the post-reaction.
[0037] The reaction mixture is then cooled to 0 to 70° C., preferably to 20 to 40° C., and then withdrawn from the reaction vessel. Customarily, the contents of the reaction vessel are transferred to a distillation plant. In the distillation which is carried out either under atmospheric pressure or else under reduced pressure, solvents, unconverted reactants and secondary components are distillatively removed from the desired 3,6-dihydro-2H-pyran-2-carboxylic ester. If desired, the distillation can be carried out using columns. However, it is also possible to carry it out in the form of a thin-film distillation or via a short-path evaporator.
[0038] Owing to its special metering technique, the process according to the invention allows not only catalysts and stabilizers to be dispensed with, but also facilitates a safe performance of the reaction even on the industrial metric ton scale.
[0039] At the same time, when the same reactants are chosen, a yield of the desired 3,6-dihydro-2H-pyran-2-carboxylic esters of 30 to 80% is obtained which is higher compared to the existing prior art processes. The particular metering technique allows only a small excess of 1,3-diene to be present in each case in the system, which allows the gradual polymerization of the 1,3-diene to undesired popcorn polymers to be reduced.
[0040] Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | A process is provided for preparing 3,6-dihydro-2H-pyran-2-carboxylic esters via a thermal hetero Diels-Alder reaction of 1,3-dienes with glyoxylic esters without the use of catalysts and stabilizers using a special metering technique. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 61/482,256 filed May 4, 2011, which is incorporated as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to low head hydropower facilities, and more particularly to a moveable element and power generation system for low head facilities.
[0004] 2. Description of Related Art
[0005] Of the approximately 80,000 dams in the United States, about 2,500 of them produce some electricity. There is, therefore, a large inventory of non-hydropower producing dams. At these dams, water is released either continuously, or on an intermittent to regular basis for, among other things, flood control or irrigation purposes. Usually, governments and municipalities do not want anything to interfere with releasing water from the dams or reservoirs, or interfere with water movement downstream. Accordingly, anything fixed in the flow path of the water that might interfere with downstream water movement is undesirable to them. Previous solutions to increasing gross head pressure, which increases the potential for power generation, have involved moveable walls or flashboards that are deployed on the top of an existing dam structure to increase the gross head on a temporary basis.
[0006] Wicket-type gates have been utilized for navigation dams for over 100 years. These gates are often considered for navigable dam spillways, but they also function as non-navigable spillways. The gates can be lifted into position with a hydraulic or pneumatic cylinder applying force to the downstream side or with a gearbox. The wickets are generally held in an up position with a prop or strut that slides in a track on the lower pool side of the wicket. This allows the cylinder piston to be retracted, or extended during operating cycles.
[0007] These systems, however, are not intended for power generation, but to increase the height of the blocked water in the upper pool, thereby creating a larger gross head pressure. In some cases, the top of the existing dam is raised by these temporary walls and existing turbines positioned at the base of the dam receive increased head pressure which results in higher power production than without the higher gross head. However, none of these systems allow for the situational use of hydropower in a deployable system that may be placed in virtually any environment where low head is available while at the same time having the ability to let water pass over the turbine powerhouse during flooding events so that the turbine powerhouse does not reduce the flow of flood waters on the dam or dam spillway. Nor do any of these systems allow for a variety of combinations of turbines and movable walls to create interchangeable power generating cells and enhancements.
BRIEF SUMMARY OF THE INVENTION
[0008] An advantage of the present invention is to provide a system for converting low head dams into hydropower facilities, while still allowing near maximum discharge during flood events of the dam.
[0009] Another advantage of the present invention is to provide a system for converting low head dams into hydropower facilities while providing minimal interference with water flow during floods.
[0010] A further advantage of the present invention is to use a wicket gate type dam with integrated and interchangeable cells to convert moving water to electricity, and a variety of mechanical methods to raise and lower moveable elements.
[0011] Another advantage of the present invention is to provide a system that uses a hydropower turbine attached to a movable element that increases available gross head pressure.
[0012] In accordance with a preferred embodiment of the present invention, there is shown a low head power generating system having a wall pivotably attachable to a structure for moving between a generally upright position and a generally flat position wherein the structure impounds water, and a power generating cell connected to the wall rotatable by movement of water there-through and operably connectable to a generator.
[0013] In accordance with another embodiment of the invention, there is shown a low head power generating system having a pivotable wall that pivots between an operable position and an inoperable position movably attached to the top of a structure that impounds water when in the operable position, a turbine disposed in the wall rotatable by the impounded water as it moves across the turbine wherein the turbine is operably connectable to a generator, and a supporting member for bracing the wall when in the operable position.
[0014] In accordance with another embodiment of the invention, there is shown a low head power generating system having a pivotable wall fixedly attachable to the top of a structure that pivots between a generally upright position and a generally flat position wherein the structure impounds water creating an upper pool side, a power generating cell operably connected to the wall through movement of water and operably connectable to a generator, and a supporting member for bracing the wall when in the upright position.
[0015] Other objects and advantages will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, embodiments of the present invention are disclosed.
BRIEF DESCRIPTION OF THE FIGURES
[0016] The novel features believed to be characteristic of the invention are set forth in the appended claims and claims yet to be filed. However, the invention itself, as well as a preferred mode of use and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying Figures wherein:
[0017] FIG. 1 is a side view schematic of a preferred embodiment of the present invention.
[0018] FIG. 2 is a side view schematic of another preferred embodiment of the present invention showing a knee brace and deployment of the invention.
[0019] FIG. 3 is a side view schematic of another preferred embodiment of the present invention showing an inflatable bladder.
[0020] FIG. 4 is a side view schematic of another preferred embodiment of the Present invention showing a pressurized piston.
[0021] FIG. 5 is an elevational view of another preferred embodiment of the invention showing a group of modular turbines, inflatable bladders, and raisable walls.
[0022] FIG. 6 is a side cross sectional view of FIG. 5 taken along line 6 - 6 .
[0023] FIG. 7 is an elevational view of another preferred embodiment of the invention showing a series of moveable bladder raisable walls and modular turbine generator cells.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Detailed descriptions of the preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Various aspects of the invention may be inverted, or changed in reference to specific part shape and detail, part location, or part composition. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
[0025] Turning first to FIG. 1 , there is shown a wall 21 having an integrated, interchangeable turbine and generator combination 25 disposed in wall 21 to create a power generating cell 20 . Cell 20 may be placed on the side of wall 21 or, in some embodiments, disposed completely flush into the wall. As illustrated more closely in the embodiment shown in FIGS. 1 , 2 and 3 , one end of wall 21 is connected to pivoting members 27 that permit wall 21 to be raised and lowered from approximately zero (0) degrees to approximately ninety (90) degrees. In some environments it may be preferable to raise wall 21 to more or less than ninety (90) degrees relative to the water surface of the upper pool 32 . In the illustrated figures, water lever is depicted as 32 . It will be appreciated that when wall 21 is raised, there exists an upper pool 33 , shown to the right of wall 21 in the figures, and a lower pool 34 , shown to the left in the figures. As can be appreciated, this is due to the natural direction of water flow and can be altered as the environment requires.
[0026] As further illustrated in FIG. 1 , the lower end of wall 21 may be pivotally attached to a structure such as the top of dam wall 35 already in place, or to the top of the cell as shown in FIG. 5 . The existing dam structure creates a certain amount of head pressure, which may be enhanced by placement of a series of cells 20 and walls 21 according to the present invention along a line transverse to the flow in the body of water. In other settings with no existing dam, the walls of the present invention may be supported by structures at the bottom of the water channel and deployed as needed to create a low head dam.
[0027] In one embodiment as shown in FIG. 1 , where cell 20 is placed on the surface of the wall, there may be a reciprocal depression 30 in the structure or on the bottom of the water channel 37 to receive cell 20 when in a down or non-generating position. In this way wall 21 is protected during floods and does not present any impediment to the flow of water.
[0028] As appreciated by those of skill in the art, cell 20 is positioned below water lever 32 in the lower pool 34 , and thereby also below the water level 32 in the upper pool 33 . The exact position of cell 20 below the water level in the lower pool can be modified according to the desired result.
[0029] As will also be appreciated, wall 21 is illustrated in a particular position in the figures, though wall 21 may be raised or lowered according to the particular environment employed. In addition, the water level 32 on either side of wall 21 is illustrated only to show the level above cell 20 and is not depicted in any specific level as is needed for the instant invention.
[0030] FIG. 2 shows wall 21 on an embodiment of the present invention in two positions (a) and (b), along with knee brace 41 that may be employed to hold wall 21 in position while in the upright position, or any operable position between the zero (0) degree and ninety (90) degree position. First end 42 of knee brace 41 is connected to the upper portion 22 of wall 21 and second end 44 is moveably attached to the structure on the floor of the water channel 37 (shown in FIG. 1 ) or the dam structure to which it is attached, similar to the embodiment illustrated in FIG. 1 . Second end 44 may be connected to a rolling member that permits the second end 44 to move between one position where the wall is flat to a second position where the wall is upright in any of a number of positions from zero (0) degrees to approximately ninety (90) degrees and is shown in FIG. 2 by the double-arrowed line, illustrating potential movement of second end 44 in both directions allowing movement of wall 21 . Second end 44 may be fixedly attached on the structure or dam to maintain the force on knee brace 41 , which in turn maintains wall 21 in a water blocking position. In the upright position (b) shown in FIG. 2 , with knee brace 41 omitted for clarity, wall 21 creates a block, thus raising the level of water level 32 to create additional head pressure. This permits water to flow through cell 20 , thus generating power.
[0031] In an alternate embodiment as shown in FIG. 3 , inflatable bladder 51 may be deployed on the downstream side of wall 21 to raise and lower wall 21 into an operable position, two potential positions of which are shown as (a) and (b). Bladder 51 may be filled with a pressurized fluid such as water or a hydraulic oil system, but may also include air, for increasing the size of the bladder and in turn raising and lowering wall 21 as desired. Similar to FIG. 2 , wall 21 may be placed on the top of an existing dam or along the bottom surface of the body of water. Another embodiment includes having the wall 21 connected to the top of the cell 20 with the turbines connected to the existing dam as shown in FIG. 5 . A series of such walls 21 may be employed to create a kind of moveable dam that creates a low head power generating station. The water that would otherwise be blocked by the wall flows through cells 20 , thereby generating power.
[0032] In another alternate embodiment shown in FIG. 4 , second end 44 of knee brace 41 may be attached to a pressurized piston 47 that in turn raises and lowers wall 21 upon activation.
[0033] FIG. 5 shows a series of modular bladder raisable wall and turbine combinations that may be employed in an existing dam. Bladders are labeled 51 , similar to those illustrated in FIG. 3 , while turbine and generator combination are labeled 25 similar to those in FIG. 1 . Also similar to FIG. 1 , dam wall 35 is shown. Turbine and generator combinations 25 are positioned to receive head power from the existing dam, but have placed on top of them an additional head producing wall 21 .
[0034] FIG. 6 shows a cross section view of FIG. 5 taken along line 6 - 6 and illustrates that wall 21 is raisable in this embodiment with bladder 51 as previously described to create additional head. The power generating cell depicted in FIGS. 5 and 6 may be preexisting within a dam structure or added to an existing dam.
[0035] FIG. 7 shows a series of bladders 51 and walls 21 that may be moveable and placed in various positions with fixed turbine and generator combinations 25 , or in combination with moveable turbine and generator cells depending on the circumstances. Any combination of power generating cell and raisable wall may be employed depending on the existing dam, the terrain, or flow characteristics of the body of water. As shown in FIG. 7 , the inflatable bladder module may be inserted in different positions among the turbine generator cells. In alternative embodiments, the turbine and generator cells may also be moveable and configured with moveable walls to achieve the desired power from the body of water.
[0036] As noted above, the individual cells may be configured as part of the moveable wall as shown in FIGS. 1-4 , and be designed for modular placement in or alongside an existing dam structure.
[0037] In any of these embodiments, the wall may be disposed on the bottom surface of the water body, on the top of a turbine cell or on the top of an existing dam structure for the purpose of creating additional head. The turbine and generator cell upon activation of the wall are thus engaged with sufficient gross head to turn the turbine and create power. By deploying a series of these walls across a body of water, power may be generated without interfering with the current flow of the body of water. Further, in the event of a flood or other need to clear the water channel of debris or ice, these walls may be lowered and placed in such a position as to not interfere with navigation or otherwise impede the flow of water.
[0038] While the invention has been described in connection with preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims, and claims that may issue. | A low head power generating system is disclosed including a wall pivotably attachable to a structure for moving between a generally upright position and a generally flat position. In the upright position, the structure or wall impounds water, and has a power generating cell connected to the wall, which rotates by movement of water there-through and is operably connectable to a generator for generating power. A support braces the wall in the upright position. The support is adjustable with a first end connected to the wall and a second end extended against a structure, and can be an inflatable bladder, a pressurized piston or other mechanism to move the wall. The cell can be mounted on the surface of the wall or integrated within the wall. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved constraining grate which alleviates the tendency for standard grates to vibrate, rattle and become dislodged. Grates which are used to support articles over stove burners in stoves within various types of recreational vehicles are particularly susceptible to these problems. Various types of constraining mechanisms for the standard grates have been developed.
2. Description of Prior Art
The problem of unstable grates has existed for some time. The solution to this problem has been to develop various forms of external clips, which are used to secure the grate to a stove. U.S. Pat. No. 2,444,862, U.S. Pat. No. 3,170,457, U.S. Pat. No. 3,263,676, and U.S. Pat. No. 3,416,513 all describe grate-constraining devices which embody some form of external clip. The use of these external clips is generally undesirable because they are difficult to install, vibrate loose, and often get misplaced.
U.S. Pat. No. 2,571,741 discloses a grate and drip pan combination wherein the grate is "adapted to seat on the shoulder and to resiliently engage the angular wall of the drip pan so that the grate cannot shift with respect to the drip pan." However, the combination grate and drip pan, as disclosed, is generally unstable, and as a unit displays the type of undesirable characteristics which this invention is designed to overcome. Often on various stove grates a downward projection is included which is designed to prevent the grate from rotating while resting on the stove. The projection used in this manner, however, serves no function associated with securing the grate to the stove.
SUMMARY OF THE INVENTION
It is an object of this invention to provide an improved constraining grate which alleviates vibration, rattle, and dislodgement of the grate without the necessity of external clips.
The improved constraining grate incorporates a circumferentially resilient structural circumferential member and a means for support attached to the structural member which provides support for articles when placed thereon. The support means permit the compression of the structural member and provide a plurality of protrusions which extend outside the structural member, three of which have downward projections. A receiving unit has holes in it which are located to accept the projections when the improved constraining grate is installed. The improved constraining grate is installed by manually compressing the structural member and fitting the projections into the corresponding holes, then releasing the structural member wherein the projections are bound inside the holes, thus securing the improved grate to the receiving unit.
A further object of this invention is to provide an improved constraining grate which would be used over stove top burners on stoves within unstable environments such as any form of recreational vehicle.
A further object of this invention is to provide an improved constraining grate that is easily manufactured, inexpensive to fabricate, and easy to install.
A further object of this invention is to provide an improved constraining grate that can be adapted to most stove tops with only minor reconfiguration of the stove top required.
BRIEF DESCRIPTION OF THE DRAWINGS
The following is a brief descriptive of the accompanying drawings.
FIG. 1 is an oblique diagram of the constraining grate.
FIG. 2 is an oblique diagram of the constraining grate when installed over stove top burner.
FIG. 3 is a vertical section of an installed constraining grate, substantially on line 3--3 of FIG. 2, showing a side view of the right projection.
FIG. 4 is a vertical section of an installed constraining grate, substantially on line 4--4 of FIG. 2, showing a side view of the left projection.
FIG. 5 is a vertical section of an installed constraining grate, substantially on line 5--5 of FIG. 2, showing a side view of the opposite projection.
FIG. 6 is a vertical section of an installed constraining grate, substantially on line 6--6 of FIG. 2, showing a rear view of the left projection.
FIG. 7 is a vertical section of an installed constraining grate, substantially on line 7--7 of FIG. 2, showing a rear view of the right projection.
FIG. 8 is a vertical section of an installed constraining grate, substantially on line 8--8 of FIG. 2, showing a rear view of the opposite projection.
FIG. 9 is a vertical section of a constraining grate, substantially on line 6--6 of FIG. 2, showing a rear view of the left projection during installation.
FIG. 10 is a vertical section of a constraining grate, substantially on line 7--7 of FIG. 2, showing a rear view of the right projection during installation.
FIG. 11 is a vertical section of a constraining grate, substantially on line 5--5 of FIG. 2, showing a side view of the opposite projection during installation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As illustrated in FIG. 1, the improved constraining grate 2 embodies the same basic structure as commonly used grates. The improved constraining grate 2 provides a structural member 4 which is circumferentially resilient and fabricated such that a gap 6 is provided in the structural member 4 to permit circumferential compression of the structural member 4. A means for support is attached to the structural member 4 to provide support for articles placed thereon. The particular design of the support means is generally irrelevant except that the support means used must permit and may not prevent the circumferential compression of the structural member 4. As illustrated in the figures, "V" shaped support members 8, which are welded to the structural member 4, are quite suitable.
The support members 8 have a plurality of protrusions 10 distributed around the structural member 4 which extend outside the structural member 4. Three of the protrusions 10, which are themselves distributed around the structural member 4, have downward projections 12. The projection 12 closest to the gap 6 in the counterclockwise direction, as viewed from the top of the constraining grate 2, is the right projection 14. Similarly, the projection 12 closest to the gap 6 in the clockwise direction is the left projection 16. Finally, the remaining projection 12 is the opposite projection 18.
The constraining grate 2 operates in combination with a receiving unit such as a stove top 20. The stove top 20 is prepared with a depression 22, around a burner 24 which protrudes therethrough. The depression 22 is prepared such that the structural member 4 fits inside the depression 22 and the protrusions 10 rest on the stove top 20 outside the depression 22. The stove top 20 has three holes 26 in it distributed around the depression 22 such that the holes 26 will accept the projections 12 when the constraining grate 2 is installed.
FIG. 3, FIG. 7 and FIG. 10 illustrate the right projection 14. FIG. 3 shows that the right projection 14 has vertical inside and outside edges. FIG. 7 and FIG. 10 show that the lower portion of the right projection 14 is bent away from the gap 6 in a counterclockwise direction.
FIG. 4, FIG. 6 and FIG. 9 illustrate the left projection 16. FIG. 4 shows that the left projection 16 has vertical inside and outside edges. FIG. 6 and FIG. 9 show that the lower portion of the left projection 16 is bent away from the gap 6 in a clockwise direction.
FIG. 5, FIG. 8 and FIG. 11 illustrate the opposite projection 18. FIG. 8 shows that the opposite projection 18 is vertical and not bent in either the clockwise or counterclockwise direction. FIG. 5 and FIG. 11 show that the opposite projection 18 has a vertical outside edge and that its inside edge is beveled, with the bottom portion of the projection wider than its top portion.
The constraining grate 2 is installed by first inserting the opposite projection 18 into the corresponding hole 26, as shown in FIG. 11. After the opposite projection 18 is inserted, the constraining grate 2 is pulled toward the gap 6 which wedges the lower portion of the opposite projection 18 under the edge of its receiving hole 26, as shown in FIG. 5. The structural member 4 is then circumferentially compressed, closing the gap 6 and permitting the left projection 16 and the right projection 14 to be simultaneously inserted into the corresponding holes 26 as shown in FIG. 9 and FIG. 10, respectively. After the left projection 16 and the right projection 14 are inserted, the structural member 4 is released and the resilient action of the structural member 4 opens the gap 6 and binds the left projection 16 and the right projection 14 under the edges of their receiving holes 26, as shown in FIG. 6 and FIG. 7, respectively.
While other specific variations of the concept could easily be developed, the precise structure described herein is considered best for fabricating the improved constraining grate. Specifically recognized as a variation of the constraining grate is one where the projections have no special construction and are merely vertical projections. While the variation using merely vertical projections satisfactorily meets the desired objectives, the first described structure is considered best.
Using the above description, those skilled in the particular art of grate fabrication could easily construct this constraining grate, or variant forms thereof. Such variant forms are to be considered within the scope and essence of this invention. | An improved constraining grate adapted to alleviate vibration, rattle, and dislodgement of the improved constraining grate. This invention utilizes a circumferentially resilient structure with downward projections which are accepted by holes within the receiving unit and which are bound therein. | 5 |
This application claims the benefit of Taiwan application Serial No. 102111928, filed Apr. 2, 2013, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates in general to a memory controller, and more particularly to a memory controller applied to a double-data-rate dynamic random access memory (DDR DRAM).
2. Description of the Related Art
A double-data-rate dynamic random access memory (DDR DRAM), featuring a fast access speed and low costs, is a common temporary data storage component in a computer system or in an electronic device. With the continual evolvement of DDR DRAM, current computer systems or electronic devices are mostly equipped with a DDR generation-3 (DDR3) DRAM. An accessing unit, such as a central processing unit (CPU), a graphic processing unit (GPU) or other peripheral element, requires a memory controller to access the DDR3 DRAM.
With the progressing development of memory technologies, a DDR generation-4 (DDR4) DRAM has become available. However, memory address configurations of the DDR3 DRAM and the DDR4 DRAM are different. For example, a DDR3 DRAM address includes a bank address, a row address and a column address. According to the DDR4 DRAM specification, a DDR4 DRAM address includes a bank address, a bank group address, a row address and a column address. That is, compared to the DDR3 DRAM address, the DDR4 DRAM address additionally includes the bank group address.
Further, based on the DDR4 DRAM specification, there are more parameters that limit data access. Thus, in a DDR4 DRAM system, a memory controller needs a novel method for generating a memory address to effectively utilize the DDR4 DRAM.
SUMMARY OF THE INVENTION
A memory controller is provided by the present invention. The memory controller, connected to a double-data-rate dynamic random access controller (DDR DRAM) and an accessing unit, includes: a processing unit, configured to receive a system address generated by the accessing unit; and a mapping unit, located in the processing unit, configured to convert the system address to a memory address and forwarding the memory address to the DDR DRAM. A burst length of the DDR DRAM is set to be L and L=2 x , and an (x+1) th bit from a least significant bit (LSB) of the memory address is included in a bank group address of the memory address, where L and x are positive integers.
A method for generating a memory address is further provided by the present invention. The method, for addressing a DDR DRAM, includes: determining parameters of a memory address associated with the DDR DRAM, the parameters including an Rn-bit row address, a Bn-bit bank address, a Gn-bit bank group address, and a Cn-bit column address; determining a burst length of the DDR DRAM as L, where L=2 x ; setting [(x−1):0] bits in a received system address as a first-part column address COL[(x−1):0]; and setting an [x] bit of the system address to be included in the Gn-bit bank group address.
A method for generating a memory address for addressing a DDR DRAM is further provided by the present invention. The method includes: determining a memory address of the DDR DRAM, the memory address including a bank group address; determining a burst length of the DDR DRAM as L, where L=2 x ; receiving a system address; and setting an (x+1) th bit from a least significant bit (LSB) of the system address to be included in the bank group address of the memory address.
The above and other aspects of the invention will become better understood with regard to the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a system of a DDR4 DRAM according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of associated signals when a memory controller sends out write instructions;
FIG. 3 is a schematic diagram of a mapping unit converting a system address to a DDR4 memory address;
FIG. 4 is a flowchart of a method for generating a DDR4 memory address according to an embodiment of the present invention;
FIG. 5A and FIG. 5B are an address table of a 16 GB DDR4 memory formed by four 4 GB dies, and a schematic diagram of a DDR4 memory address generated according an embodiment of the present invention;
FIG. 6 is a flowchart of a method for generating a DDR4 memory address according to an embodiment of the present invention; and
FIG. 7 is a schematic diagram of a DDR4 memory address generated according an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a schematic diagram of a memory access system.
In FIG. 1 , a DDR4 memory is taken as an example, and other DDR DRAMs may also be applied. A memory controller 110 is connected to multiple accessing units 102 , 104 and 106 , and a DDR4 memory 120 . Each of the accessing units 102 , 104 and 106 accesses data from the DDR4 memory 120 via the memory controller 110 .
The memory controller 110 includes an arbitration unit 112 and a processing unit 114 . The processing unit 114 includes a mapping unit 116 . As shown in FIG. 1 , the arbitration unit 112 is connected to all of the accessing units 102 , 104 and 106 , and arbitrates the access priority to the DDR4 memory 120 for the accessing units 102 , 104 and 106 .
For example, when the arbitration unit 112 determines that the accessing unit 102 has permission to access the DDR4 memory 120 , a read instruction and a system address generated by the access unit 102 are transmitted to the processing unit 114 . The mapping unit 116 in the processing unit 114 converts the system address into a memory address compliant to the specification of the DDR4 memory 120 , and then transmits the read instruction and the memory address to the DDR4 memory 120 . The DDR4 memory 120 retrieves data according to the memory address, and forwards the retrieved data to the accessing unit 102 via the memory controller 110 to complete a current read transaction.
Similarly, when the accessing unit 102 wishes to write data, a write instruction, a system address and data are transmitted to the processing unit 114 . After the mapping unit 116 in the processing unit 114 converts the system address into a memory address, the processing unit 114 forwards the write instruction, the memory address and the data to the DDR4 memory 120 . The DDR4 memory 120 records the data according to the memory address to complete a current write transaction.
It is known from the above description, after the mapping unit 116 receives the system address, the system address needs to be first converted into a memory address that is then forwarded to the DDR4 memory 120 . The DDR4 memory 120 completes the transaction according to the memory address and the instruction.
According to the DDR4 memory specification, a DDR4 memory address includes a bank address, a bank group address, a row address and a column address. When successively accessing data, an interval between time points at which instructions are sent out is restricted by tCCD_L and tCCD_S parameters. That is to say, when the memory controller 110 successively sends out two read or write instructions to the DDR4 memory 120 , a time interval tCCD_L is required between the two instructions if the two corresponding bank group addresses in the memory address are the same. On the other hand, when the memory controller 110 successively sends out two read or write instructions to the DDR4 memory 120 , a time interval tCCD_S is required between two instructions if the two corresponding bank group addresses in the memory address are different. Wherein, tCCD_L>tCCD_S. In the description below, tCCD_L is exemplified by a period of 6 clocks (6T), and tCCD_S is exemplified by a period of 4 clocks (4T) for explanation purposes.
FIG. 2 shows a schematic diagram of associated signals when the memory controller 110 sends out write instructions. It is assumed that the memory controller 110 is to send out three write instructions Write 0 , Write 1 and Write 2 , the instruction Write 0 corresponds to the bank group address (BG) bg 0 in the memory address, the instruction Write 1 corresponds to the bank group address (BG) bg 0 in the memory address, and the instruction Write 2 corresponds to the bank group address (BG) bg 1 in the memory address.
As shown in FIG. 2 , the write instruction Write 0 generated at the time point T 0 corresponds to the memory group address (BG) bg 0 . As the instruction Write 1 also corresponds to the bank group address (BG) bg 0 , according to the specification of tCCD_L, the memory controller 110 generates the instruction Write 1 at the time point T 6 , and between the time points T 0 and T 6 is a no-operation (NOP) period. Further, as the instruction Write 2 corresponds to the bank group address (BG) bg 1 , according to the specification of tCCD_S, the memory controller 110 generates the instruction Write 2 at the time point T 10 , and between the time points T 6 and T 10 is a no-operation (NOP) period. It is apparent that, the instructions Write0 and Write 1 are spaced by 6 clocks (6T), and the instructions Write 1 and Write2 are spaced by only 4 clocks (4T).
It is known from the above description, the utilization efficiency of the DDR4 memory gets higher when a change occurs in the bank group address (BG) as successively instructions are written. Conversely, the utilization efficiency of the DDR4 memory gets lower when no change occurs in the bank group address (BG) as successive instructions are written.
Similarly, an interval between time points at which read instructions are sent out is also restricted by tCCD_L and tCCD_S parameters, and associated details are omitted herein.
FIG. 3 shows a schematic diagram of the mapping unit 116 converting a system address into a memory address of a DDR4 memory. In general, after the mapping unit 116 receives the system address of an accessing unit, the system address is divided into four parts from a most significant bit (MSB) to a least significant bit (LSB) according to the DDR4 memory specification, and the four divided parts are sequentially utilized as a row address (ROW), a bank address (BA), a bank group address (BG), and a column address (COL). In FIG. 3 , the DDR4 memory address includes an Rn-bit row address (ROW[Rn−1:0]), a Bn-bit bank address (BA[Bn−1:0]), a Gn-bit bank group address (BG[Gn−1:0]), and a Cn-bit column address (COL[Cn−1:0]).
However, when the mapping unit 116 of the memory controller 110 generates the DDR4 memory address according to the method in FIG. 3 , the utilization efficiency of the DDR4 memory is severely lowered as the DDR4 memory address is successively accessed. One reason for such occurrence is that, the successively accessed DDR4 memory address only causes the column address (COL[Cn−1:0]) to change while leaving the bank group address (BG[Gn−1:0]) unchanged. Therefore, when the memory controller 110 accesses the successive DDR4 memory address, the utilization efficiency of the DDR4 memory is lowered due to the restriction posed by the tCCD_L parameter.
In the present invention, the method that the mapping unit 116 generates the DDR4 memory address is changed under the architecture in FIG. 1 . As such, a restriction is posed by only the tCCD_S parameter when the memory controller 110 accesses the successive DDR4 memory address, and the utilization efficiency of the DDR4 memory can thus be effectively enhanced. Associated details are given below.
FIG. 4 shows a method for generating a DDR4 memory address according to a first embodiment of the present invention. In step S 402 , parameters of the DDR4 memory address are determined, including the Rn-bit row address, the Bn-bit bank address, the Gn-bit bank group address, and the Cn-bit column address, where Rn, Bn, Gn and Cn are positive integers. In step S 404 , a burst length of the DDR4 memory is determined to be L, where L=2 x . In general, the burst length L of the DDR4 memory may be set to 8 or 4, and x is then 3 or 2. That is, L and x are positive integers greater than 0.
In step S 406 , bits [(x−1):0] of the system address are set as a first-part column address COL[(x−1):0]. In step S 408 , bits [(x+Gn−1):x] of the system address are set as the bank group address BG[Gn−1:0]. In step S 410 , bits [(Cn+Gn−1):(x+Gn)] of the system address are set as a second-part column address COL[Cn−1:x]. In step S 412 , bits [(Cn+Gn+Bn−1):(Cn+Gn)] of the system address are set as the bank address BA[Bn−1:0]. In step S 414 , bits [(Cn+Gn+Bn+Rn−1):(Cn+Gn+Bn)] of the system address are set as the row address ROW[Rn−1:0]. That is to say, according to the above method, the mapping unit 116 may translate the system address into the DDR4 memory address, which is arranged from the MSB to the LSB as ROW[Rn−1:0], BA[Bn−1:0], COL[Cn−1:x], BG[Gn−1:0], and COL[(x−1):0].
FIG. 5A and FIG. 5B are an address table of a 16 GB DDR4 memory formed by four 4 GB dies, and a schematic diagram of a DDR4 memory address generated according the first embodiment of the present invention. Fundamentally, the 16 GB DDR4 memory may also be formed by eight 2 GB dies or sixteen 1 GB dies. With different compositions, the numbers of the row address, column address, bank group address and bank address may be different. In the description below, a 16 GB DDR4 memory formed by four 4 GB dies is taken as an example for explaining the present invention, not limiting the present invention.
According to the DDR4 memory specification, parameters of the address of the 16 GB DDR4 memory formed by four 4 GB dies are known. More specifically, the DDR4 memory needs a row address having 18 bits from A 0 to A 17 (Rn=18), a column address having 10 bits from A 0 to A 9 (Cn=10), bank group addresses BG 0 and BG 1 having a total of 2 bits (Gn=2), and bank addresses BA 0 and BA 1 having a total of 2 bits (Bn=2). Further, it is assumed that the burst length of the DDR4 memory is set to 8, where 8=2 x and x=3.
As shown in FIG. 5B , bits [ 2 : 0 ] (i.e., [(x−1):0]) of the system address are set as the firs-part column address COL[ 2 : 0 ] (i.e., COL[(x−1):0]) of the DDR4 memory address, bits [ 4 : 3 ] (i.e., [(x+Gn−1):x]) of the system address are set as the bank group address BG[ 1 : 0 ] (i.e., BG[(Gn−1):0]) of the DDR4 memory address, bits [ 11 : 5 ] (i.e., [(Cn+Gn−1):(x+Gn)]) of the system address are set as the second-part column address COL[ 9 : 3 ] (i.e., COL[(Cn−1):x]) of the DDR4 memory address, bits [ 13 : 12 ] (i.e., [(Cn+Gn+Bn−1):(Cn+Gn)]) of the system address are set as the bank address BA[ 1 : 0 ] (i.e., BA[(Bn−1):0]) of the DDR4 memory address, and bits [ 31 : 14 ] (i.e., [(Cn+Gn+Bn+Rn−1):(Cn+Gn+Bn)]) of the system address are set as the row address ROW[ 17 : 0 ] (i.e., ROW[(Rn−1):0]) of the DDR4 memory address. Thus, the DDR4 memory address generated by the mapping unit 116 is arranged from the MSB to the LSB as ROW[ 17 : 0 ], BA[ 1 : 0 ], COL[ 9 : 3 ], BG[ 1 : 0 ], and COL[ 2 : 0 ].
In the embodiment, as the burst length of the DDR4 memory is 8, when the memory controller 110 accesses the successive DDR4 memory address, the 4 th bit from the LSB of the DDR4 memory address, i.e., the (x+1) th bit, continues changing. The 4 th bit is included in the bank group address BG[ 1 : 0 ]. When the memory controller 110 accesses the successive DDR4 memory address, the bank group address BG[ 1 : 0 ] continues changing such that the instructions generated by the memory controller 110 are restricted by only the tCCD_S parameter, thereby effectively enhancing the utilization efficiency of the DDR4 memory.
With the above description, a method and apparatus for generating a DDR4 memory address are disclosed by the present invention. When the burst length of a DDR4 memory is L and L=2 x , the mapping unit 116 sets the (x+1) th bit from the LSB of the system address as the (x+1) th bit from the LSB of the DDR4 memory address, and the (x+1) th bit is included in the bank group address. Thus, when the memory controller 110 accesses the successive DDR4 memory address, the instructions generated by the memory controller 110 are restricted by only the tCCD_S parameter, thereby effectively enhancing the utilization efficiency of the DDR4 memory.
FIG. 6 shows a method for generating a DDR4 memory address according to a second embodiment of the present invention. In step S 602 , parameters of the DDR4 memory address are determined, including the Rn-bit row address, the Bn-bit bank address, the Gn-bit bank group address, and the Cn-bit column address. In step S 604 , a burst length of the DDR4 memory is determined to be L, where L=2 x .
In step S 606 , bits [(x−1):0] of the system address are set as a first-part column address COL[(x−1):0]. In step S 608 , bits [(x+y−1):x] of the system address are set as a first-part bank group address BG[y−1:0], where y is a positive integer greater than 0 and smaller than or equal to Gn. In step S 610 , bits [(Cn+y−1):(x+y)] of the system address are set as a second-part column address COL[Cn−1:x]. In step S 612 , bits [(Cn+Gn−1):(Cn+y)] of the system address are set as a second-part bank group address BG[Gn−1:y]. In step S 614 , bits [(Cn+Gn+Bn−1):(Cn+Gn)] of the system address are set as a bank address BA[Bn−1:0]. In step S 616 , bits [(Cn+Gn+Bn+Rn−1):(Cn+Gn+Bn)] of the system address are set as a row address ROW[Rn−1:0].
According to the above approach, the mapping unit 116 translates the system address into the DDR4 memory address, arranging from the MSB to the LSB into ROW[Rn−1:0], BA[Bn−1:0], BG[Gn−1:y], COL[Cn−1:x], BG[y−1:0], and COL[(x−1):0].
FIG. 7 shows a schematic diagram of a DDR4 memory address generated according to the second embodiment of the present invention. The DDR4 memory address in FIG. 7 is generated according to an addressing table of the 16 GB DDR4 memory formed by four 4 GB dies in FIG. 5A .
Similarly, according to the specification of the DDR4 memory in FIG. 5A , parameters of the address of the 16 GB DDR4 memory formed by four 4 GB dies are known. More specifically, the DDR4 memory needs a row address having 18 bits from A 0 to A 17 (Rn=18), a column address having 10 bits from A 0 to A 9 (Cn=10), bank group addresses BG 0 and BG 1 having a total of 2 bits (Gn=2), and bank addresses BA 0 and BA 1 having a total of 2 bits (Bn=2). Further, it is assumed that the burst length of the DDR4 memory is set to 8, where 8=2 x and x=3.
When y is equal to 1, as shown in FIG. 7 , bits [ 2 : 0 ] of the system address are set as a first-part column address COL[ 2 : 0 ] of the DDR4 memory, bit [3] of the system address is set as the bank group address BG[ 0 ] of the DDR4 memory, bits [ 10 : 4 ] of the system address are set as a second-part column address COL[ 9 : 3 ] of the DDR4 memory, bit [ 11 ] of the system address is set as the bank group address BG[ 1 ] of the DDR4 memory, bits [ 13 : 12 ] of the system address are set as the bank address BA[ 1 : 0 ] of the DDR4 memory, and bits [ 31 : 14 ] of the system address are set as the row address ROW[ 17 : 0 ] of the DDR4 memory. In the embodiment, the DDR4 memory generated is arranged from the MSB to the LSB as ROW[ 17 : 0 ], BA[ 1 : 0 ], BG[ 1 ], COL[ 9 : 3 ], BG[ 0 ], and COL[ 2 : 0 ].
According to the second embodiment of the present invention, in the DDR4 memory address, the 4 th bit from the LSB, i.e., the (x+1) th bit, continues changing. The (x+1) th bit is included in the bank group address BG[ 1 : 0 ]. Therefore, when the memory controller 110 accesses the successive memory address, the bank group address BG[ 1 : 0 ] continues changing such that the instructions generated by the memory controller 110 are restricted by only the tCCD_S parameter, thereby effectively enhancing the utilization efficiency of the DDR4 memory.
In the second embodiment of the present invention, when y is set to 2, the DDR4 memory address generated is as shown in FIG. 5B , and associated details shall be omitted herein.
In the present invention, during the process that the mapping unit 116 converts the system address into the DDR4 memory address, the DDR4 memory address, starting from the (x+1) th bit from the LSB, is mapped into the bank group address. Thus, the utilization efficiency of the DDR4 memory is effectively enhanced when the memory controller accesses the successive DDR4 memory address.
In the present invention, at other addresses of the DDR4 memory address, e.g., the row address or the bank address, the object of enhancing the utilization efficiency of the DDR4 memory may also be achieved through a method other than the arrangement methods in FIGS. 5B and 7 . In other words, in the first embodiment in FIG. 4 , the arrangement of the address subsequent to step S 410 may be appropriately modified. Similarly, in the second embodiment in FIG. 6 , the arrangement of the address subsequent to step S 610 may also be appropriate modified to similarly achieve the object of the present invention.
While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures. | A memory controller is connected to a double-data-rate dynamic random access memory (DDR DRAM) and an accessing unit. The memory controller includes: a processing unit, configured to receive a system address generated by the accessing unit; and a mapping unit, located in the processing unit, configured to convert the system address to a memory address and transmitting the memory address to the DDR DRAM. When a burst length of the DDR DRAM is L and L=2 x (where L and x are positive integers), an (x+1) th bit of the memory address from a least significant bit (LSB) is included in a bank group address of the memory address. | 6 |
BACKGROUND OF THE INVENTION
1. Description of the Prior Art
The invention relates to a device by means of which the pile warp threads can be taken into more than three different positions with the aid of a selection element with interacting complementary hooks on a movable lifting device (which form an open-shed element) and two vertically movable grates to which a reversing roller is immovably connected.
French Patent No. 1,050,774 discloses how four positions can be obtained with two hooks or two selection elements, a movable bottom board and a lifting device. The disadvantage of this device is that two selection elements are needed in each case. In the case of an electronic Jacquard machine, for example, this becomes very expensive.
Belgian Patent Application No. 09200461 (unpublished on Apr. 23, 1993) discloses how three different positions of the pile warp threads can be obtained with a selection element and two interacting complementary hooks on said selection element which are connected to a movable lifting element with a vertically movable grate to which a reversing roller is immovably connected.
The object of the invention is to improve these devices in such a way that they are capable of more than three positions while only one selection element is necessary.
SUMMARY OF THE INVENTION
The object of the invention is to improve on the prior art devices by in that the Jacquard machine is capable of placing pile threads in more than three positions, while only one selection element is needed.
The Jacquard machine for weaving two fabrics between which pile threads extend, is provided with, for each pile thread, a device such as a harness cord from which a heald is suspended, and an element for placing each heald and, thus, each pile thread, in several positions.
The machine according to the invention comprises a first system for binding a first series of pile threads into a first fabric, and a second system for binding a second series of pile threads into a second fabric. Each the two systems have the following elements:
•a selection element with two vertically movable complementary hooks under the action of two knives, which move in counterphase in an up and down movement;
•a cord-and-pulley element, which comprises
a movable lifting element having a top roller and
a bottom roller,
a pulley cord, which connects said complementary hooks, said pulley cord being passed under the top roller of said movable lifting element,
a reversing roller located below the movable lifting element, and
a position cord which is connected to one of the complementary hooks and passed under the reversing roller, then over the bottom roller of the movable lifting element, and then down to the heald device from which the heald is suspended;
•a vertically movable grate, to which the reversing roller is attached; and
•means for moving the grate with one of the two knives.
The first system is adapted so that it is able to position the heald device among three positions, namely a top position, a bottom position, and a first intermediate position. The second system is adapted so that it is able to position the heald device among three positions, namely the top position, the bottom position, and a second intermediate position.
The grates are preferably connected in such a way to one of the two knives that a lift of the knife over a certain length corresponds to a lift of the grate of the second system which differs from the lift of the grate of the first system.
Other features and details of the invention will emerge from the description which follows with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In said drawings:
FIG. 1 shows in perspective a part of a Jacquard machine according to the invention;
FIG. 2 shows a side view of the part illustrated in FIG. 1;
FIG. 3 shows a part in perspective from FIG. 1, but enlarged;
FIGS. 4 to 11 show working steps of the machine shown in FIG. 1;
FIGS. 12 to 15 show the lie of the pile threads during weaving with the Jacquard machine with four positions;
FIGS. 16 to 23 show working steps of a Jacquard machine with five positions and with four grippers; and
FIGS. 24 to 27 show the lie of the pile threads during weaving with the Jacquard machine with five positions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The Jacquard machine which is shown partially in FIG. 1 is designed for weaving of face-to-face carpet or velvet, consisting of a bottom fabric and a top fabric between which pile threads are stretched.
Each pile thread passes through a heald which is linked to a system by means of which the vertical position of the heald can be controlled.
For the pile threads which are provided for binding into the bottom fabric the system comprises:
--a selection element with two vertically movable complementary hooks 1, 2 under the action of two knives 11, 12 moving in counterphase, in an up and down movement B; the hooks 1, 2 are connected by a cord 3 which is passed round the top roller 4 of a movable lifting element 5;
--a cord 6 which is connected to one (2) of the complementary hooks is passed round a reversing roller 7 fixed to a first vertically movable grate 8, and is then passed over the bottom roller 9 of the movable lifting device 5 and run to the heald 13; and
--the first vertically movable grate 8 is driven by one (12) of the upgoing and downgoing knives.
Three positions for the heald 13 can be obtained by means of this system, namely a bottom position O when the knife 11 is lowered while hook 1 is not selected (FIG. 8), a top position B when the knife 12 is lowered while hook 2 is selected (FIG. 9), and a bottom middle position MO when knife 11 is lowered while hook 1 is selected or when knife 12 is lowered while hook 2 is not selected (FIGS. 10 and 11).
For the pile threads which are provided for binding into the top fabric the system comprises:
--a selection element with two vertically movable complementary hooks 1, 2 under the action of two knives 11, 12 moving in counterphase, in an up and down movement; the hooks are connected by a cord 3 which is passed round the top roller of a movable lifting element;
--a cord 6 which is connected to one (1) of the complementary hooks, and is passed round a reversing roller fixed to a second vertically movable grate 14, and is then passed over the bottom roller 9 of a movable lifting device and run to the heald 13;
--the second vertically movable grate 14 driven by one of the upgoing and downgoing knives 11, 12 and to which the reversing roller is connected, and
--a mechanism 15 which is connected to the second grate 14 and is driven together with a knife (12).
In one embodiment, the mechanism comprises a lever which is rotatable relative to a shaft and which is connected to a knife and a grate in such a way that a vertical movement of the knife over a length (L) corresponds to a vertical movement of the grate over a distance which differs from the above-mentioned length (L).
According to one feature of said embodiment, the second grate is rotatably connected to a rod which is rotatably connected to the lever.
According to another feature of said embodiment, a knife of the selection element of the second series of elements, or a piece supported by said knife, is rotatably connected to a rod, which rod (hereinafter called rod of the knife) is rotatably connected to the lever.
According to one embodiment, the ratio between the distance between the shaft of the lever and the pivot point of the rod of the knife on the lever and the distance between the shaft of the lever and the pivot point of the rod of the grate on the lever is higher than 1.1 or lower than 0.9. Said ratio preferably lies between 0.2 and 0.9 and between 1.1 and 2. In particular, the ratio is approximately 0.5 or 1.5.
According to a specific embodiment, the first grate is driven in such a way together with one of the upgoing and downgoing knives with lift L that it moves over a length L, while the second grate is driven in such a way together with one of the upgoing and downgoing knives with lift L that it moves over a length L/2 or 1.5 L.
In a preferred embodiment, the first grate and the second grate are driven by the same system, in which a series of first knives of the selection elements of the first elements and a series of first knives of the selection elements of the second elements move in phase over a certain length (L), while a series of second knives of the selection elements of the first elements and a series of second knives of the selection elements of the second elements move in phase over the above-mentioned length (L), which movement of said second knives is in counterphase to the movement of the above-mentioned first knives.
Other features and details of the invention will emerge from the description which follows with reference to the appended drawings.
Three positions for the heald 13 can be obtained by means of this system, namely a bottom position 0 when the knife 11 is lowered while hook 1 is not selected (FIG. 4), a top position B when the knife 12 is lowered while hook 2 is selected (FIG. 5), and a top middle position MB when knife 11 is lowered while hook 1 is selected, or when knife 12 is lowered while hook 2 is not selected (FIGS. 6 and 7).
The knives 11 are fitted on a carrier 16, while the knives 12 are fitted on a carrier 17, the knives being driven by a single drive system so that the knives and the knives 12 move in counterphase.
The grates 8, 14 are connected to the carrier 7 by means of rods 18.
The mechanism 15 comprises a lever which is mounted on a shaft 22, so that said lever is rotatable relative to the frame of the machine (not shown).
A first rod 18 extends between the carrier 17 and the free end 19 of the lever 15. Said rod 18 is rotatably connected to the carrier 17, and also to the lever 15. The lever 15 is rotatably connected to the grates 8, 14 by rods 20, 21. The rod 20, which is rotatably connected to the grate 8, is connected to the shaft 23 forming the connection between the lever 15 and the rod 18, while the rod 21 is rotatably connected to the lever by means of a shaft 24 lying between the shaft 23 and the shaft 22. The ratio between the distance v between the shaft 22 or pivot point of the lever and the pivot point of the rod 21 on the lever 15 and the distance V between the shaft 22 or pivot point of the lever 15 and the shaft 23 is 0.5, so that a vertical movement of the knives 12 over a length L corresponds to a vertical movement of the grate 8 over a length L and to a vertical movement of the grate 14 over a length L/2.
FIGS. 4 to 7 show the positions of the heald 13 for a pile thread provided for binding into the top fabric.
In FIG. 4 the knife 11 is in the bottom position, while the knife 12 is in the high position. In that way the heald 13 is in its bottom position O (lie of active pile thread shown in FIG. 12).
FIGS. 6 and 7 show the position of the system for binding a pile thread into the top fabric. The heald 13 is in a position lying between the bottom position O and the top position B. The distance between that position MB and bottom position O is 2×L, while the distance between that position and the top position is 1×L.
FIG. 5 shows the position of a thread which is provided for binding into the top fabric and forms pile on shot No. 2 (FIG. 13). This thread must be in top position B. Between shot No. 1 and shot No. 2 knife 11 and knife 12 have changed position. Hook 2 is selected by a selection element of the system and thereby remains at the top. Hook 1 has risen along with knife 11, and has thereby risen over distance L. Cord 6 has consequently risen a distance L, and heald 13 has thus risen a distance L. Cord 3 has also risen a distance L, with the result that hoist 5 rises L/2 and by way of cord 6 heald 13 thus again rises L. Due to the fact that knife 12 has dropped over distance L, grate 14 has dropped over distance L/2 and by way of roller 7 and cord 6 the heald 13 thus again rises L. So heald 13 has risen a total of 3×L and is therefore situated in top position (B).
FIG. 6 shows the situation of a pile thread which is provided for binding into the top fabric and is bound in on shot No. 1. This thread must be in top middle position (MB) .
Compared with the situation in FIG. 4, knives 11 and 12 are in the same position, as is grate 14. However, hook 1 is selected by a selection element of the system and is thus L higher up than the position in FIG. 4. The result is that cord 6 has risen L, and heald 13 has thus risen L. Cord 3 has also risen L, with the result that hoist 5 rises L/2, and by way of cord 6 heald 13 thus again rises L. In total, the heald in the situation in FIG. 6 is thus 2 L higher than in the situation in FIG. 4, i.e. in position MB.
FIG. 7 shows the situation of a pile thread which is provided for binding into the top fabric and is bound in at shot No. 2. This thread must be in top middle position (MB).
For comparison with the situation in FIG. 5, hook 2 is not selected, with the result that it is L lower than in the situation in FIG. 5. This means that hoist 5 is L/2 lower, and heald 13 is thus L lower than the situation in FIG. 5, i.e. in position MB.
FIGS. 8 to 11 show positions of the heald 13 for a pile thread which is provided for binding into the bottom fabric (bottom position O--FIG. 8; top position B--FIG. 9) and for a pile thread bound into the bottom fabric.
On shot No. 1 knife 11 is down and knife 12 is up (FIG. 8). The difference in position between the two is L. The hook 1 rests on knife 11, and the hook 2 rests on knife 12. Book 1 and hook 2 are connected by way of a cord 3. Hook 2 is also connected to cord 6, which is connected to the heald 13 by way of the roller 7 and hoist 5. Roller 7 is fixed to a movable grate 8 which is immovably fixed to knife 12 by way of a rod. Grate 8 thus makes the same movement as knife 12.
FIG. 8 shows the position of a pile thread which is provided for binding into the bottom fabric and forms pile on shot No. 1. This thread must be in bottom position (O).
FIG. 9 shows the situation of a thread which belongs to the bottom fabric and forms pile on shot No. 2. This thread must be in top position (B). Between shot No. 1 and shot No. 2 knife 11 and knife 12 have changed position. Book 2 has been selected by a selection element and therefore remains at the top. Book 1 has risen along with knife 11 and has therefore risen L. This means that cord 3 has risen L, with the result that hoist 5 rises L/2, and by way of cord 5 heald 13 has consequently risen L. Due to the fact that knife 12 has dropped over distance L, grate 8 has dropped over distance L, and by way of roller 7 and cord 5 heald 13 has thus again risen 2 L.
In total, heald 13 has thus risen a distance 3×L, so it is situated in top position (B).
FIG. 10 shows the situation of a pile thread which is provided for binding into the bottom fabric and is bound in on shot No. 1. This thread must be in bottom middle position (MO).
For comparison with the situation in FIG. 8, knives 11 and 12 are in the same position, as is grate 8. However, hook 1 has been selected by a selection element and is thus situated L higher than in the situation in FIG. 8. This means that cord 3 has risen L, and heald 13 has thus risen L, with the result that the latter is in position MO.
FIG. 11 shows the position of a pile thread which is provided for binding into the bottom fabric and is bound in on shot No. 2. This thread must be in bottom middle position (MO).
For comparison with the situation in FIG. 9, hook 2 is not selected here and is therefore L lower than in the situation in FIG. 9, with the result that cord 6 has dropped L, so that heald 13 has dropped L. Cord 3 has also dropped L, with the result that hoist 5 drops L/2, and by way of cord 6 heald 13 thus drops L again. In all, heald 13 has thus dropped 2×L compared with the situation in FIG. 9, and is thus in position MO.
The Jacquard machine according to the invention can reach 4 positions:
* On shot 1 the positions O and MB are possible for pile threads which are provided for binding into the top fabric, and the positions O and MO are possible for pile threads which are provided for binding into the bottom fabric (see FIGS. 12 and 13, FIGS. 4, 6, 8 and 10).
* On shot 2 the positions B and MB are possible for threads of the top fabric, and the positions B and MO are possible for threads of the bottom fabric (see FIGS. 14 and 15, FIGS. 5, 7, 9 and 11).
Methods using the machine according to the invention of FIG. 1 are shown diagrammatically in FIGS. 12 to 15. These methods require two weaving loom cycles for making a pile thread from the top fabric or the bottom fabric form pile, or for binding it in.
FIGS. 12 and 13 show a first shot of a method for binding in an active pile thread 117 from the top fabric 100 and an active pile thread 118 from the bottom fabric 200, while FIGS. 14 and 15 show the second shot for the pile threads.
In the method, weft threads are inserted by stationary grippers G1, G2, G3 between binding warp threads 103, 104 in order to tie off the pile threads.
In FIGS. 12 and 13 the binding threads 103, 104 of the top fabric 100 are given a lift such that they cross each other and the shed α defined between the binding threads 103, 104 allows gripper G1 to pass, and binding threads 103, 104 of the bottom fabric 200 are given a lift such that the shed β defined between the binding threads allows the grippers G2 and G3 to pass. Three weft threads can be inserted simultaneously by these grippers.
The tension warp thread 109 of the top fabric 100 extends in the vicinity of the binding thread 103 of the top fabric 100 above the grippers G1, while the bound-in pile thread 115 in the top fabric extends in the vicinity of the binding thread 104 below the gripper G1, so that the gripper G1 can be moved into the shed formed between the tension warp thread 109 and the bound-in pile thread 115.
The tension warp thread 110 of the bottom-fabric 200 and the bound-in pile thread 116 in the bottom fabric are taken into a position between the grippers G2 and G3, binding warp thread 3 above G2, binding warp thread 4 and pile warp thread 117 below G3, so that a double shed is formed for the bottom fabric.
During the second shot (see FIGS. 14 and 15) the binding threads 103, 104 of the top fabric 100 and the binding threads 103, 104 of the bottom fabric 200 are moved in such a way that the binding threads 103, 104 of the bottom fabric 200 cross each other, and the shed γ defined between the binding threads 103, 104 of the top fabric 100 and the shed δ defined between the binding threads 103, 104 of the bottom fabric 200 allow through two grippers G1, G2 for the top fabric (thus two weft threads) and the gripper G3 for the bottom fabric respectively.
The lie of the tension warp thread 109 of the top fabric 100 and the bound-in pile thread 115 in the top fabric 100 is adapted in such a way that the tension warp thread 109 and the pile thread 115 extend between the weft threads inserted by the grippers G1, G2.
The tension warp thread 110 of the bottom fabric extends in the vicinity of the binding thread 103 of the bottom fabric 200, while the bound-in pile thread 116 in the bottom fabric extends in the vicinity of the binding thread 104, so that the gripper G3 can be moved into the shed δ defined between the tension warp thread 110 and the pile thread 116.
In order to bind a pile thread 117 from the top fabric 100, the lie of said thread 117 is adapted in such a way that during the first shot (FIG. 12) two grippers G2, G3 are allowed through into the shed defined between the pile thread 117 and the binding thread 103 of the bottom fabric 200, and during the second shot (FIG. 14) two grippers G1, G2 are allowed through into the shed defined between the pile thread 117 and the binding thread 104 of the top fabric.
As can be seen from FIGS. 12 and 14, for each shot a pile thread 117 is moved in such a way relative to the last inserted weft threads that said pile thread rests on a weft thread of a fabric and runs to the tension warp thread of the other fabric in order to divide the shed defined between the binding threads of the other fabric into a first part lying between an intersection of the binding threads of the fabric and the pile thread, and into a second part which relative to the pile thread lies in a direction opposite to the above-mentioned intersection, in order to permit the insertion of one or two weft threads into the abovementioned part.
A pile thread 118 from the bottom fabric can be bound in, for example, as follows:
During a first shot, the lie of the thread 118 is adapted so that said thread lies next to the binding thread 104 of the bottom fabric, and so that two grippers G2, G3 are allowed through into the shed defined between the thread 118 and the binding thread 103 of the bottom fabric 200 (FIG. 13).
In a second shot, the lie of the thread 118 is adapted in such a way that the thread 118 lies next to the binding thread 103 of the top fabric, and the two grippers G1, G2 are allowed through into the shed defined between thread 118 and binding thread 104 of the top fabric. During this second shot the binding threads 103, 104 of the bottom fabric 200 are moved in such a way that said binding threads cross each other and a shed forms, which shed allows through a gripper G3 in order to insert a weft thread.
FIGS. 16 to 23 show the positions of a heald 13 for a Jacquard machine (similar to that shown in FIGS. 4 to 11), with five positions, namely a bottom O, a top B, and three middle positions M1, M2, M3.
The weaving loom can then weave with four grippers G1, G2, G3, G4, which are moved between B and M1, between M1 and M2, between M2 and M3, and between M3 and O respectively, or are stationary.
This five-position Jacquard works in the same way as the Jacquard with four positions described above. It differs from the abovementioned previous Jacquard in the following points:
--For pile threads which are provided for binding into the top fabric, grate 8 is immovably fixed to knife 12. Grate 8 thus follows the same movement as knife 12 and between shot 1 and shot 2 moves over the distance L, instead of over distance L/2 (as in FIG. 5). This means that heald 13 in the situation in FIG. 17 and in the situation in FIG. 19 is L higher than in FIGS. 5 or 7.
--For pile threads of the bottom fabric, grate 14 is connected by way of a lever system 15 to the knife 12. Grate 14 follows the movement of knife 12 with a gain factor of 3/2. Between shot 1 and shot 2 grate 14 moves over the distance 3/2 L instead of over distance L. This means that heald 13 in the situation in FIG. 21 and the situation in FIG. 23 is L higher than in FIGS. 9 or 11.
The Jacquard can thus achieve five positions:
* On shot 1 the positions O and M2 are possible for threads of the top fabric, and the positions O and M3 are possible for threads of the bottom fabric.
* On shot 2 the positions B and M1 are possible for threads of the top fabric, and the positions B and M2 are possible for threads of the bottom fabric.
Instead of four grippers, the machine can also have three grippers, which are movable vertically, i.e. the lie of the grippers G1, G2, G3 being controlled (with upgoing and downgoing grippers).
Furthermore, in that machine only one selection element per harness cord is needed to ensure that the hooks are taken into one of the five positions.
The machine with four grippers is provided with a device for inserting three weft threads per shot. On shot No. 1, grippers G21, G31 and G41 act in order to insert weft threads (one in the top fabric, and two in the bottom fabric), while on shot No. 2 grippers G11, G21 and G31 act in order to insert weft threads (two in the top fabric, and one in the bottom fabric).
The lie of the active pile threads 117, 118, tension warp threads 109, 110, binding threads 103, 104 and bound-in pile threads 115, 116 shown in FIGS. 24 to 27 is the same as the lie of the abovementioned threads in FIGS. 12 to 15. | A Jacquard machine for weaving face-to-face fabrics consisting of a bottom fabric and a top fabric between which pile threads are stretched, incorporating two systems, one for each fabric. For each pile thread, the machine incorporates a selection element with hooks under the action of knives, a cord which is connected to one of the hooks, a lifting device, and a grate which is driven together with one of the knives. The invention enables pile warp threads to be taken into more than three different positions with the aid of a single selection element, thereby reducing the cost and size of the Jacquard machine. | 3 |
BACKGROUND
[0001] The present invention relates to a packaging for a consumer product.
[0002] Many consumer products are scented. Often, a consumer wishes to sample the scent before purchasing the product in a store. When the product is a product such as an anti-perspirant or deodorant composition winch is sold in a roll-on or stick format, there is a problem that a user may remove the cap protecting the roll-ball or stick to try to sample the scent of the composition within the container. Other consumer products, such as liquid soap and detergents may have a seal that would have to be removed in order to sample the scent.
[0003] Historically, shoppers of roll-on products tend to remove the cap to smell the packaged product, often spinning the ball with their finger in order to wet the finger with the product, and then replace the cap. Shoppers of stick products also tend to open the cap to smell the packaged product, often causing the dome, or factory finish, which temporarily protects the underlying stick and allows for filling during manufacture, to fall out. The dome is sometimes referred to as the “factory finish” by those skilled in the art. The primary purpose of the dome is to allow filling of the container with the product when the container is in an inverted position, a secondary purpose being to protect the stick prior to use. Replacing the dome and/or touching the product compromises the presentation of the package and renders it potentially unsealable.
[0004] Similarly, shoppers of other consumer products may also compromise package presentation. In consumer products like liquid soap or detergent, the shopper may remove a seal to smell the product. If the shopper decides to purchase the product, they often pick an untampered package, but replace the product which they sampled back onto the shelf, which can cause the now compromised product to be damaged and be potentially unsaleable.
SUMMARY
[0005] The present invention aims to provide a consumer product which is packaged to allow shoppers to sample the scent of the product without opening the package or compromising the package's factory-fresh presentation.
[0006] The cap is typically located at the top of the container, but alternatively the cap may be located at the bottom of the container, for example on a secondary cap which seals the bottom of the container after a filling step in which the container is inverted. Typically, the manually deformable pan comprises a flexible membrane. In a preferred embodiment, in which the cap is located at the top of the container, the manually deformable part is disposed at an upper surface of the cap. Optionally, the manually deformable part comprises a majority of the upper surface of the cap. Correspondingly, in an alternative embodiment, in which the cap is located at the bottom of the container, the manually deformable part is disposed at a lower surface of the cap, and for example comprises a majority of the lower surface of the cap The manually deformable part may be composed of a thermoplastic elastomer. Typically, the orifice is composed of an elastic material which maintains the orifice in a substantially closed condition in the absence of a pressure differential across the orifice. The orifice may be provided in a thermoplastic elastomer. In one embodiment, the manually deformable part and the orifice are provided in a common body of thermoplastic elastomer. Optionally, the manually deformable part has an external surface shaped with a recess for receiving a finger of a user.
[0007] The present invention accordingly provides a consumer product comprising a container for containing a scented composition and a cap fitted to the container, the cap and the container defining a cavity therebetween, the cap having an orifice, for communicating between the cavity and an exterior of the cap, and a manually deformable part which is adapted to be displaceable thereby to displace air from an internal location within the cavity outwardly through the orifice.
[0008] Typically, the manually deformable part comprises a flexible membrane. In a preferred embodiment, the manually deformable part is disposed at an upper surface of the cap. Optionally, the manually deformable pan comprises a majority of the upper surface of the cap. The manually deformable part may be composed of a thermoplastic elastomer. Typically, the orifice is composed of an elastic material which maintains the orifice in a substantially closed condition in the absence of a pressure differential across the orifice. The orifice may be provided in a thermoplastic elastomer. In one embodiment, the manually deformable part and the orifice are provided in a common body of thermoplastic elastomer. In another embodiment, the manually deformable part and the orifice are provided in a common body of injection moldable or blow moldable resin, for example polypropylene. Optionally, the manually deformable pan has an external surface shaped with a recess for receiving a finger of a user.
[0009] The consumer product may further comprise a tamper evident element connecting together the container and the cap.
[0010] In some embodiments, the container is a roll-ball container containing a liquid composition. In other embodiments, the container contains a solid stick of the composition. Typically, the composition is an anti-perspirant or deodorant composition.
[0011] The present invention also provides a packaged consumer product comprising a container containing a scented personal care composition, selected from a liquid and a solid personal care composition, and a scent sampler for displacing air which contains the scent from an internal location within the package to outside the package without opening the package.
[0012] Typically, the scent sampler comprises a manually deformable part and an orifice, the manually deformable part being adapted to be displaceable thereby to displace air from the internal location outwardly through the orifice. The packaged consumer product may further comprise a tamper evident element sealing the package. In one embodiment, the container is a roll-ball container containing a liquid antiperspirant or deodorant composition. In another embodiment, the container contains a stick of a solid anti-perspirant or deodorant composition. In a further embodiment, the container contains a soap or body wash composition. In a yet further embodiment, the container contains a detergent or fabric softener.
[0013] The present invention further provides a method of packaging a consumer product, the method comprising the steps of:
[0014] (a) disposing a scented composition in a container, the composition being selected from a liquid and a solid composition;
[0015] (b) applying a cap to the container to seal the container, the cap including a manually actuatable scent sampler for displacing air located between the cap and the container to outside the package without opening the package; and
[0016] (c) permitting scent from the composition to become infused in the air located between the cap and the container.
[0017] The present invention yet further provides a method of sampling the scent of a consumer product, the method comprising the steps of:
[0018] (a) providing a packaged consumer product comprising a container for containing a scented composition, selected from a liquid and a solid composition; and
[0019] (b) displacing air which contains the scent from an internal location within the package to outside the package without opening the package.
[0020] Accordingly, the embodiments of the invention can provide that the scent of the packaged composition can be sampled by a prospective purchaser by sampling the scent of the actual packaged product but without opening the package, exposing the packaged product, or compromising the integrity of the packaging or the packaged consumer product.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a schematic perspective view of an upper portion of a roll-on container for a personal care product such as an antiperspirant or deodorant composition in accordance with a first embodiment of the present invention;
[0022] FIG. 2 is a schematic side view of the roll-on container of FIG. 1 when used to provide a scent preview to a user;
[0023] FIG. 3 is a schematic perspective view of a cap for a container for a consumer product in accordance with a second embodiment of the present invention; and
[0024] FIG. 4 is a schematic perspective view of a cap for a container for a consumer product in accordance with a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] Referring to FIG. 1 , there is shown a schematic perspective view of an upper portion of a roll-on container 2 in accordance with a first embodiment of the present invention.
[0026] The container 2 includes a body portion 4 and a cap 6 which is removably mounted thereon, for example by conventional helical threads (not shown). The body portion 4 packages a consumer product such as an antiperspirant or deodorant composition. The cap 6 covers and protects a roll-ball 14 (shown in phantom in FIG. 1 ) Which is mounted in conventional manner at an end 7 of the body portion 4 . The cap 6 includes a flexible portion 8 , in the form of a membrane, which can he manually depressed by a user. Typically, the flexible portion 8 is located in an upper wall 9 of the cap 6 and takes up the major proportion of the upper surface of the cap 6 . A surrounding skirt 11 of the cap 6 depends downwardly from the upper wall 9 and is threadably fitted to the end 7 of the body portion 4 . A flexible insert 10 defining an outlet orifice 12 is located in the skirt 11 . The outlet orifice 12 is typically maintained in a substantially closed condition by the elastic properties of the flexible insert 10 in the absence of a pressure differential across the outlet orifice 12 . Therefore, when the packaged container is not being handled manually to sample the scent as described below, the cap is substantially sealed. The cap 6 defines a closed cavity 15 above the roll-ball 14 which is infused with scent from the consumer product packaged within the container 2 .
[0027] The cap 6 on the one hand, and the flexible portion 8 and insert 10 an the other hand, may be composed of a two plastic materials, and are typically bi-injection molded, with the flexible portion 8 and the insert 10 being composed of a relatively flexible material, such as a thermoplastic elastomer, and the upper wall 9 and the skirt 11 being composed of a relatively rigid material, such as polypropylene. The flexible portion 8 and the insert 10 may be separated, as shown, or connected together. Alternatively, the cap 6 , flexible portion 6 and insert 10 may be composed. of a single plastic material, with the flexible portion 8 having a thinner wall thickness as compared to the upper wall 9 and skirt 11 to provide the required flexibility for the flexible portion 8 and an orifice 12 sufficiently small in cross-section or sealed so that the scent is retained within the cavity 15 prior to sampling, as described below. Optionally, a flexible hinge (not shown may be provided between the flexible portion 8 and the upper wall 9 .
[0028] As shown in FIG. 2 , when a shopper wishes to sample the scent of the consumer product packaged within the container 2 , the shopper can manually depress the flexible portion 8 with their finger F. This causes the flexible portion $ to be flexed inwardly, thereby reducing the volume of the closed cavity 15 , which in turn causes a corresponding volume of the scent-infused air within the closed cavity 15 to he displaced. outwardly through the orifice 12 , to form a scent-release S from the cavity 15 . The pressure differential across the orifice 12 causes the flexible insert 10 to deform thereby temporarily to open up the orifice 12 to permit the scent release. The scent can then be sampled by the shopper. The scent can be sampled without removing the cap 6 of the packaged product, and so the package is not opened to sample the scent. Moreover, the scent of the packaged product itself may be sampled, and not the scent of a separately provided sample which may differ perceptibly from the actual packaged product.
[0029] After the manual pressure is released, the flexible portion 8 and the insert 10 , which are resilient or elastic, return to their initial configuration. This permits the scent of the product to be sampled again by a subsequent shopper.
[0030] In order to direct the shopper to the scent sampling feature, the product may be labeled with printed information to highlight the scent sampling flexible portion 8 to the customer. Furthermore, the container 2 may be provided with a tamper evident feature to discourage a shopper from removing the cap 6 in store to test the product. Such a tamper evident feature may be selected from, for example, a shrink band, an extended shrink label, a pressure sensitive and/or geometry molded into the packaging components, i.e. the body portion 4 and the cap 6 , to achieve the goal of keeping the package uncompromised prior to the sale of the product to a customer. FIG. 2 illustrates a tamper evident feature in the form of a pressure sensitive label 13 bridging the body portion 4 and the cap 6 . The provision of such a tamper evident feature would inhibit the consumers' typical behavior of unscrewing the cap 6 at the point of sale. In fact, hindering the opening of the cap 6 would prompt the user to take a closer look at the product and notice the scent preview feature of the present invention.
[0031] Accordingly, the consumer product is packaged to allow shoppers to sample the scent of the product without compromising the package's factory-fresh presentation.
[0032] The cap 16 is adapted for removable snap- or push-fitting over a container (not shown) for a personal care product such as a roll-on anti-perspirant or deodorant. The cap 16 covers and protects the roll-ball. The cap 16 includes a relatively flexible substantially planar top wall 18 mounted on a relatively rigid skirt 20 which is shaped and dimensioned to fit onto a container. The top wall 18 is typically composed of a thermoplastic elastomer and the skirt 20 is typically composed of polypropylene. The top wall 18 includes an orifice 22 extending therethrough which is surrounded by an annular depression 24 constituted by a thinning of the material of the top wall 18 . As illustrated in FIG. 3 , the orifice 22 is located on an annular side surface 26 of the top wall 18 above the skirt 20 .
[0033] Referring to FIG. 3 , there is shown a schematic perspective view of a cap 16 for a consumer product container in accordance with a second embodiment of the present invention.
[0034] The cap 16 is adapted for removable snap- or push-fitting over a container (not shown) for a consumer product such as an anti-perspirant or deodorant stick. The cap 16 could also contain threads for threaded coupling with a container (not shown) for a consumer product such as a body wash, liquid soap, fabric softener, detergent and the like. The cap 16 covers and protects the free end of a container knot shown). The cap 16 includes a relatively flexible substantially planar top wall 18 mounted on a relatively rigid skirt 20 which is shaped and dimensioned to fit onto a container. The top wall 18 is typically composed of a thermoplastic elastomer and the skirt 20 is typically composed of polypropylene. The top wall 18 includes an orifice 22 extending therethrough which is surrounded by an annular depression 24 constituted by a thinning of the material of the top wall 18 . As illustrated in FIG. 3 , the orifice 22 is located on an annular side surface 26 of the top wall 18 above the skirt 20 .
[0035] As for the embodiment of FIGS. 1 and 2 , manual pressure acting on the top wall 18 can flex the top wall, thereby to reduce the volume of the closed cavity between the cap 16 and the container, which in turn causes a corresponding volume of the scent-infused air within the closed cavity to be displaced through the orifice 22 , to form a scent-release from the cavity.
[0036] FIG. 4 shows a schematic perspective view of a cap 26 for a consumer product container in accordance with a third embodiment of the present invention, which is a modification of the cap of the second embodiment shown in FIG. 3 .
[0037] The cap 26 is, again, adapted for removable snap-fitting over a container (not shown) for a consumer product such as an anti-perspirant or deodorant stick, body wash, liquid soap, detergent, fabric softener and the like. The cap 26 could alternatively comprise threads for mating with threads on a neck of a container (not shown). The cap 26 includes a relatively flexible top wall 30 mounted on a relatively rigid skirt 34 which is shaped and dimensioned to fit onto a container. The top wall 30 includes a central depression or recess 36 surrounded by an annular upwardly inclined surface 38 terminating in an annular ridge 40 around the cap 26 . The top wall 30 is typically composed of a thermoplastic elastomer and the skirt 34 is typically composed of polypropylene. The top wall 30 includes an orifice 32 extending therethrough which is surrounded by an annular depression 42 constituted by a thinning of the material of the top wall 30 . As illustrated in FIG. 4 , the orifice 32 is located, on an annular side surface 44 of the top wall 30 above the skirt 34 .
[0038] The shaping of the top will 30 to include the central depression 36 provides the user with an easy to use structure for finger location above the flexible membrane for sampling the scent of the personal care product within the container.
[0039] The caps of the previous embodiments may readily be modified so as to be suitable for removable snap-fitting over a container (not shown) for a personal care product such as an anti-perspirant or deodorant in the form of a stick. For example, the shape of the cap may be modified so as to have a cross-section corresponding to that of the packaged stick, for example an oval cross-section, with correspondingly modified dimensions. The cap accordingly covers and protects the free end of a stick.
[0040] In another modification, when the container is for a stick product, the cap may be a secondary cap located at the bottom of the container, the cap sealing the bottom of the container after filling thereof with the stick composition. In such a modification, the manually deformable part may be disposed at a lower surface of the cap, and for example comprises a majority of the lower surface of the cap. Other features described earlier for the structure of the cap, when located at the top of the container, may be incorporated into such a secondary lower cap.
[0041] In a modification of any of the embodiments described, the deformable part and the orifice may be provided in a common body of injection-molded or blow-molded resin, for example polypropylene.
[0042] Other modifications to and embodiments of the present invention will be apparent to those skilled in the art. | A consumer product comprises a container for packaging a composition having a scent. A removable cap is fitted to the container, with the cap and the container defining a cavity therebetween. The cap has an orifice, for communicating between the cavity and an exterior of the cap, and a manually deformable part which is adapted to be displaceable thereby to displace air from an internal location within the cavity outwardly through the orifice. | 1 |
FIELD OF THE INVENTION
The present invention relates to orthopedic cutting blocks for use in shaping a bone and, more particularly, to an orthopedic cutting block that has been designed to permit low-cost manufacturing methods while still maintaining the required accuracy of the cuts.
BACKGROUND OF THE INVENTION
Many surgical operations call for the precise and accurate cuts of bone material. Generally, these cuts, or resections, are made using surgical saws or milling devices. These instruments, while excellent at cutting the bone material, typically require cutting guides in surgical procedures calling for accurate cuts. For example, a surgeon performing a total knee arthroplasty must make several cuts on the distal end of the femur to properly fit a prosthetic femoral component. If these resections are incorrectly made, the surgery can result in failure and require further corrective procedures.
For this and other reasons, surgeons often employ the use of surgical cutting blocks, known also as cutting guides. These blocks aid in guiding the cutting device during the cutting of the bone material. A specific type of cutting block is one used to create four cuts on an already resected distal portion of the femur as part of a total knee replacement. These four cuts are the anterior and posterior cuts and the anterior and posterior chamfer cuts. Examples of these femoral cutting blocks are shown in U.S. Pat. No. 5,454,816 to Ashby, U.S. Pat. No. 6,258,095 to Lombardo et al., and U.S. Pat. No. 6,558,391 to Axelson, Jr. et al.
While cutting blocks such as those described above are useful in performing the various cuts on a bone, they have their drawbacks. Most importantly, the manufacturing costs associated with such blocks are often quite high. A standard block is typically constructed of metallic material machined from a solid block or from several solid metal pieces and assembled to allow for the various cuts to be performed. The high costs require these expensive cutting blocks to be utilized in multiple surgeries. This re-use requires the cleaning and sterilization of such a block before each use, which adds additional cost. Furthermore, multiple uses of a cutting block allows for greater chance of misaligning a cutting tool, such as a flat oscillating saw blade, due to wear of the cutting guide surfaces. Hence, a disposable single use cutting block would be advantageous. Therefore, there is a need for a cutting block that can be inexpensively manufactured, while maintaining the required precise and accurate dimensions needed for making cuts.
SUMMARY OF THE INVENTION
A first aspect of the present invention is a bone cutting block comprising a polymeric first body portion having at least one aperture extending therethrough for receiving a bone cutting tool and a non-polymeric second body portion having a cutting tool guide surface thereon, the second body portion coupled to the first body portion with the cutting tool guide surface thereon in communication with the aperture.
In some embodiments, the first body portion has a first external surface for facing a bone and second external surface for facing away from the bone with the second body portion coupled to one of the first or second surfaces. In other embodiments, the bone cutting block further comprises a non-polymeric third body portion coupled to the other of the external surfaces. In other embodiments, one of the first, second, or third body portions further comprises means for attaching to a bone surface. In other embodiments, the means for attaching to bone surface are pins. In certain embodiments, the third body portion has a cutting tool guide surface thereon in communication with the aperture of the first body portion and the cutting tool guide surface of the second body portion. In any of these embodiments, the second and third portion may be made of metal. In some embodiments, the first body portion further comprises four apertures and the second and third body portion further comprise four cutting tool guide surfaces respectively, groups of the apertures and the cutting tool guide surfaces in communication with one another to form four passages. The cutting tool guide surfaces of this embodiment may be slots.
Another embodiment of the present invention is an orthopedic cutting block for performing four cuts on the resected distal end of the femur. This block comprises a base portion having a first side, a second side, and three slots extending from the first side to the second side, a first guide portion having four slots extending through the first guide portion, and a second guide portion having four passages extending through the second guide portion. In this embodiment, the first guide portion is attached to the first side of the base portion, the second guide portion is attached to the second side of the base portion, and the three passages of the base portion, the slot on the first guide portion and the second guide portion align to form four passages extending through the cutting block. In this embodiment, the base portion may be made of polymer material and the first and second guide portions may be made of metal. Finally, the embodiment may further include means for attaching the cutting block to a bone surface, such as pins.
Another aspect of the present invention is a method for forming an orthopedic cutting block for guiding bone saws. This method comprising injection molding a polymeric body having passageways therein, placing first and second metal plates on respective first and second sides of the polymeric body, the plates having saw guides thereon, the placement including aligning the guides with the passageways, and coupling the first and second plates with the body therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood on reading the following detailed description of non-limiting embodiments thereof, and on examining the accompanying drawings, in which:
FIG. 1 is a perspective view of the apparatus according to an embodiment of the present invention for use in resecting a distal femur in its fully constructed form with a saw blade extending through a passage;
FIG. 2 is an exploded perspective view of the apparatus according to an embodiment of the present invention showing outer metal plates and a molded plastic body;
FIG. 3 is a cross-sectional view of the apparatus according to an embodiment of the present invention as shown in FIG. 1 ;
FIG. 4 is a perspective view of a base portion according to an embodiment of the present invention;
FIG. 5 is a perspective view of a first guide portion according to an embodiment of the present invention, where the guide portion is flipped 180° from that shown in FIGS. 1 and 2 ; and
FIG. 6 is a perspective view of a second guide portion according to an embodiment of the present invention.
DETAILED DESCRIPTION
In describing the preferred embodiments of the subject matter illustrated and to be described with respect to the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific term so selected, and is to be understood that each specific term includes all technical equivalence which operate in a similar manner to accomplish a similar purpose.
As used herein, the term “distal” means more distant from the heart and the term “proximal” means closest to the heart. The term “inferior” means toward the feet and the term “superior” means towards the head. The term “anterior” means towards the front part of the body or the face and the term “posterior” means towards the back of the body. The term “medial” means toward the midline of the body and the term “lateral” means away from the midline of the body.
Referring to the drawings, wherein like reference numerals represent like elements, there is shown in FIGS. 1-6 , in accordance with embodiments of the present invention, a cutting guide, or cutting block, designated generally by reference numeral 10 . In the preferred embodiment, cutting block 10 is designed to be used in resecting a distal femur and includes a base or first body portion 12 , a first guide or second body portion 14 , and a second guide or third body portion 16 . The preferred embodiment of the present invention is a cutting block 10 used to make four cuts on the distal end of the femur, during a total knee arthroplasty, the anterior and posterior cuts and the anterior and posterior chamfer cuts subsequent to the distal cut being made. However, it should be noted that cutting block 10 could also have broad utility during any orthopedic procedure where a guide for a cutting instrument is required. For example, a cutting block using the technology used in cutting block 10 can be used during tibial preparation of a total knee arthroplasty. Cutting block 10 is shown in the figures along with oscillating saw blade 18 . Saw blade 18 is used to perform the cutting, or resecting, of the bone surface. It should be noted that other devices for cutting, as known in the art, can also be utilized, such as reciprocating saws or milling cutters.
The base portion 12 , as best shown in FIG. 4 , is made of a polymeric material. In the preferred embodiment, the base portion is manufactured by an injection molding process from commercially available Ultem® polymer. However, it should be noted that other materials can be utilized. For example, it is contemplated that polypropylene or polycarbonate can also be used to manufacture base portion 12 . Preferably, the material should be one that is easy to utilize in manufacturing the base portion 12 , while also being relatively inexpensive.
In the preferred embodiment, base portion 12 is rectangularly shaped having rectangular faces 13 and an opposite face (not shown) and passages 20 a , 23 , and 26 a extending therethrough. However, in other embodiments, base portion 12 can be other shapes and can include any number of passages therethrough. For example, a base portion 12 including only one passage can be utilized in preparing the proximal end of the tibia during a total knee arthroplasty. In the preferred embodiment, passages 20 a , 23 , and 26 a extend in the direction of axis or plane 38 (as best shown in FIG. 3 ). However, passage 23 includes walls 25 and 29 a which extend in a direction along axis or plane 40 and walls 25 b and 29 b which extend in a direction along axis of plane 42 (also best shown in FIG. 3 ). In use, axes 38 , 40 , and 42 determine the angle of the planar cuts to be made on the bone surface. As such, the angles of axes 38 , 40 , and 42 can vary depending upon the particular implant to be placed on the bone or the type of surgery being performed. Furthermore, the location of passages 20 a , 23 , and 26 a , in the anterior-posterior direction, on base portion 12 will determine the location of the cuts actually made on the bone surface. In the preferred embodiment, passages 20 a , 23 , and 26 a allow a surgeon to make the typical four cuts on the distal end of the femur, during a total knee arthroplasty.
In a preferred embodiment, saw blade 18 does not contact the various surfaces of base portion 12 . Rather, base portion 12 provides the aforementioned passages to allow saw blade 18 to traverse through base portion 12 , while working in conjunction with guide portions 14 and 16 . As shall be discussed herein, guide portions 14 and 16 provide the support needed to operate saw blade 18 . In essence, in the preferred embodiment, base portion 12 is a skeleton that provides spacing and further support to rigid guide portions 14 and 16 . However, it is contemplated that base portion 12 can be designed so as to support a cutting tool during resection of the bone surface.
The construction of base or spacer portion 12 does not require a solid piece of polymeric material to be utilized, although such could be utilized. In the preferred embodiment, as best shown in FIG. 4 , the molded polymeric base portion 12 has walls 100 , 102 , 104 , 106 around the four sides thereof with bosses 108 molded at the corners thereof. Preferably bosses 108 are threaded after molding. A stiffening rib 110 may be molded on each wall extending from a central portion of each wall generally perpendicular thereto. Flat plate portions 112 , 114 are molded adjacent surfaces 100 and 104 and spaced therefrom to provide space for a saw blade 18 to traverse the spacer portion 12 . Plate portion 112 , 114 may include integrally molded stiffening ribs 116 for rigidity. Two centrally located walls 118 , 120 extend inwardly towards the center of base portion 12 . Walls 118 , 120 are stiffened by a series of ribs 122 which are preferably spaced at regular intervals along each wall forming compartments 124 therebetween. Walls 118 and 120 are spaced at the center of base portion 12 to allow the saw blade to make the chamfer cuts. Preferably the ends of ribs 122 adjacent this central area are tapered inwardly to provide clearance for the saw blade. The taper may be equal to the 45° angle of the champfer cuts. In the preferred embodiment, walls 102 and 106 include integrally molded extensions 52 for receiving optional handles as will be discussed below. Also bone pin holes 126 are preferably molded in each side 102 and 106 to allow for a pair of pins to penetrate base portion 12 . Besides making the cutting block lighter, this type of design allows for the further reduction of expenses associated with the construction of base portion 14 and the overall expense of cutting block 10 . Such a molding results in less polymeric material being required in the manufacture of base portion 12 . However, the design allows base portion 12 to remain rigid enough to provide the proper support required in use of cutting block 10 . It is contemplated that the dimensions of base portion 12 can vary. Depending upon the type of cutting tool used, the type or size of implant to be installed, the type or size of bone to be resected, or the dimensions of the other elements of cutting block 10 , the dimensions of base portion 12 may vary accordingly. For example, base portion 12 can decrease in size with the increase in size of the other elements of cutting block 10 or can increase in size along with an overall increase in size of cutting block 10 for resecting a larger bone.
First guide portion 14 is best shown in FIG. 5 . Typically guide portion 14 is constructed of a metal, but can be constructed of any material suitable for properly supporting and guiding saw blade 18 . For example, in the preferred embodiment, first guide portion 14 is a plate 0.080 inches thick and constructed of 316 stainless steel (commonly used in medical instruments), but in another embodiment, first guide portion 14 can be constructed of other suitable material. Preferably, the material should be one that produces low friction and wear and can support a saw blade, as well as being relatively inexpensive. Such a stainless steel plate can easily be stamped in large quantities which reduces the cost of manufacturing. However, it is noted that stamping is only one method of manufacturing guide portion 14 . Depending upon the thickness of guide portion 14 , other methods of manufacturing might be required.
In the preferred embodiment, first guide portion 14 includes passages 20 b , 22 b , 24 b , and 26 b extending therethrough (best shown in FIG. 5 ). While passages 20 b and 26 b extend in a generally perpendicular direction with respect to the face of first guide portion 14 (i.e. in the direction of axis 38 ), passages 22 b and 24 b extend at an angle typically of 45 degrees. However, this angle can vary depending upon the angle of chamfer cuts required. First guide portion 14 also includes section 27 b extending between passages 22 b and 24 b . This section is essentially a triangular section extending from first guide portion 14 . Section 27 b provides a support surface for saw blade 18 and guides one side of saw blade 18 along either the axis 40 or the axis 42 .
Second guide portion 16 is shown in FIG. 6 and is similar to first guide portion 14 . In the preferred embodiment, the shape and dimensions of second guide portion 16 vary from that of first guide portion 14 , while the material utilized is the same. The variation in size and dimension is dictated by the location and angle of cuts to be made. However it is contemplated that other designs for second guide portion 16 can be utilized including a mirror image of first guide portion 14 in both shape and material. In the preferred embodiment, second guide portion 16 includes passages 20 c , 22 c , 24 c , and 26 c extending therethrough (best shown in FIG. 6 ). While passages 20 c and 26 c extend in a generally perpendicular direction with respect to the face of second guide portion 16 (i.e. in the direction of axis 38 ), passages 22 c and 24 c extend at an angle typically of 45 degrees. However, this angle can vary depending upon the angle of chamfer cuts required. Second guide portion 16 also includes section 27 c extending between passages 22 c and 24 c . This section is essentially a triangular section extending from second guide portion 16 . Section 27 c provides a support for saw blade 18 and guides one side of saw blade 18 along either the axis 40 or the axis 42 .
Passages 20 c and 26 c of second guide portion 16 correspond to passages 20 a and 26 a of base portion 12 and passages 20 b and 26 b of first guide portion 14 . In operation, the aforementioned passages cooperate with one another so that corresponding passages (e.g. 20 a , 20 b , and 20 c ) form one continuous passage (e.g. 20 ) through cutting block 10 . Furthermore, sections 27 b and 27 c allow for passages 22 b and 24 b and 22 c and 24 c , respectively, to correspond with passage 23 , thereby forming continuous passage 22 along axis 40 and continuous passage 24 along axis 42 . It should be noted that other embodiments are envisioned. For example, passage 23 in base portion 12 could be replaced with two separate passages extending along axes 40 and 42 respectively. In this alternate embodiment, first guide portion 14 would not include section 27 b and second guide portion 16 would not include section 27 c.
In the preferred embodiment, a fully constructed cutting block 10 (as best shown in FIG. 1 ) includes first guide portion 14 and second guide portion 16 attached to the opposing faces 13 and 15 of base portion 12 . The mode of attachment of first guide portion 14 and second guide portion 16 to base portion 12 can be accomplished in any manner. For example, rivets, pins, screws, or adhesive, as well as many other means for attachment can be utilized. In the preferred embodiment, as shown in FIG. 1 , screws 34 extend from first guide portion 14 through base portion 12 , and into threaded holes of second guide portion 16 . In this mode, base portion 12 , first guide portion 14 and second guide portion 16 include extended portions 35 for facilitating connection. However, it is contemplated that other configurations can also be utilized. For example, base portion 12 may include bosses or extensions that insert into guide portions 14 and 16 and retain them in contact with base portion 12 . In another embodiment, first and second guide portions 14 and 16 can be molded into the polymer of base portion 12 . Finally, base portion 12 may be designed so that guide portions 14 and 16 snap into place. It is also noted that cutting block 10 may include any variation of the elements discussed above.
In the preferred embodiment, the fully constructed cutting block includes four passages 20 , 22 , 24 , and 26 extending therethrough. Each of these passages corresponds to a different cut on the distal end of the femur, matching an implant surface. It is contemplated that cutting block 10 can include any number of passages that correspond to any required cut on any bone surface. For example, cutting block 10 can include only two passages for making only two of the aforementioned four cuts on the distal end of the femur. In the preferred embodiment, the four passages 20 , 22 , 24 , and 26 extending through cutting block 10 include passages 20 a , 23 , and 26 a of base portion 12 , 20 b , 22 b , 24 b , and 26 b of first guide portion 14 , and 20 c , 22 c , 24 c , and 26 c of second guide portion 16 . Perpendicular passages (i.e. passages 20 and 26 ) include like passages (e.g. 20 a , 20 b , and 20 c ) which correspond with one another to form one continuous passage extending through cutting block 10 (e.g. passage 20 ), while angled passages (i.e. 22 and 24 ) include sections 27 b and 27 c which correspond with like passages (e.g. passages 22 b and 22 c ) and passage 23 to form one continuous passage extending at an angle through cutting block 10 (e.g. passage 22 ). Each passage accommodates saw blade 18 and guides the same during the cutting of the bone surface. The first guide portion 14 and second guide portion 16 provide the support needed to guide saw blade 18 . It is recognized that the metallic composition of these portions allows for better support of the saw blade 18 . For this reason, as stated above, first guide portion 14 and second guide portion 16 are constructed from material that is as hard or harder than saw blade 18 and only allows movement within the aforementioned passages.
Cutting block 10 may also include elements for attaching to a bone surface. In the preferred embodiment, locating pins 28 (shown in FIG. 1-3 ) allow for the fixation of cutting block 10 to the previously resected surface of the distal end of the femur. Locating pins 28 are attached to second guide portion 14 and during use extend therefrom into the bone surface. It is noted that locating pins 28 can either be fixably attached or removably attached to second guide portion 14 . In the preferred embodiment, second guide portion 16 includes flat sections 44 and 46 for mounting pins 28 . Flat sections 44 and 46 include apertures for receiving pins 28 . These apertures can be threaded for removable attachment of pins 28 . However, other modes of attachment are contemplated. It is also contemplated that locating pins 28 can be located on any part of cutting block 10 , with or without flat sections 44 and 46 . Furthermore, locating pins 28 are only one example of a way of attaching cutting block 10 to a bone surface. Another way for attaching the cutting block 10 to a bone surface is by using bone pins 32 extending through holes in cutting block 10 (shown in FIGS. 1 and 2 ). Bone pins 32 can be aligned so as to contact the bone surface at an angle from cutting block 10 . When bone pins 32 are used, metal bushings 50 (shown in FIG. 2 ) can be inserted into polymeric portion 12 to provide better support. Additionally, an external support system can be employed to fix cutting block 10 with respect to the bone surface to be resected.
The width of cutting block 10 in the medial-lateral direction of the femur and the height of the cutting block 10 in the anterior-posterior direction of the femur are chosen based on the size of the distal femur being resurfaced and the femoral implant being used. Thus, various sized cutting blocks 10 may be utilized. Cutting block 10 may be aligned on the distal femur in any well known manner, such as by using an intramedulary or extramedulary alignment systems or by computer assisted navigation.
As depicted in FIGS. 1 and 2 , the preferred cutting block 10 of one embodiment of present invention includes handles 30 . Handles 30 are preferably detachable from cutting block 10 , such as by being threaded. It is also contemplated that base portion 12 can include extensions 52 for more easily attaching handles 30 . As is known, handles 30 aid in the aligning and fixing of cutting block 10 with respect to the bone surface to be resected. In use, a surgeon grasps handles 30 and guides cutting block 10 into place. Thereafter, cutting block 10 is fixed using any of the means for attaching to a bone surface described above.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | An orthopedic cutting block for use in shaping a bone. The cutting block having at least two components, one of which is made of a polymeric material. The cutting block allowing for precise and accurate cuts to be made, while being inexpensive to manufacture and disposable after a single use. | 0 |
ORIGIN OF THE INVENTION
This invention was made with government support under grant number ECD-8721551 awarded by the National Science Foundation. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in mechanical dryers for drying thick polymer-solvent layers on a substrate. More particularly, this invention is for producing and controllably applying a gradient-temperature heated air to a substrate having a thick polymer-solvent layer in order to avoid forming bubbles in the polymer layer during drying.
2. Description of the Related Art
Conventionally, it has been recognized that the latter stage of polymer solution drying is controlled by diffusion, but the application of diffusion controlled drying on dryer design has not been fully appreciated. This is largely because experiments performed imply a strong concentration dependence for the rate of diffusion. At present it appears that the dependence is even greater than that represented by existing semi-empirical diffusion models.
The typical industrial dryer for drying a polymeric coating consists of a series of zones each with a controlled temperature and airflow rate. A high drying rate enhances the process speed but may be detrimental to the quality of a final coating because of effects such as "skinning" and boiling of the solvent. The drying of polymeric films in manufacturing situations is carried out in dryers consisting of different zones. The solution of polymers and solvents is applied to a substrate by using a coater. The substrate can be a variety of materials and surfaces. An example is a web matrix used for photoreceptor belts.
The substrate with the wet film enters a series of temperature zones, each of which is at a determined temperature by applying a controlled flow of heated air. When the design in the dryer does not allow for increased temperature or airflow, air convection dryers can be augmented by supplying energy directly to the bulk of the drying film by exposing it to some sort of radiation that can be absorbed by the film. The temperatures, airflow rates and the speed of the substrate are chosen such that the residual solvent concentration at the end of the drying process is acceptable while providing the maximum yield.
Modeling the process permits optimizing the design of the dryer and to identify potential trouble spots. One problem is the boiling of the solvent in the wet film, which can result in the formation of defects in the final product, such as bubbles. Current dryer design strategies utilize high heat transfer rates and only a few relatively long temperature zones. Generally, this type of dryer design is inefficient in maximizing solvent removal rates and generally ineffective in preventing bubble formation. These small bubble formations in polymer layer, such as a small molecule transport layer of a flexible photoreceptor belt, have been a significant problem for years.
Despite early improvements in dryers, no further progress has been made in the last few years. Recently, extensive experiments in the mechanism of small molecule transport layer drying have demonstrated that conventional dryer designs such as longer zones, air bar design, and lower temperatures, cannot solve the problem. The only way to eliminate small molecule transport layer bubbles is by careful temperature profiling of a dryer.
SUMMARY OF THE INVENTION
The present invention is drawn to a dryer design having a continuous temperature gradient throughout the dryer, especially in the critical latter stages of drying, where the solvent content of the film is less than 20%. Even though the ideal and most preferred situation is to have a continuous temperature gradient, it is possible to build a dryer with discrete temperature zones that approximates the ideal. In this case, the preferred embodiment is to ensure a zone residence time of less than 10 seconds and a web heating rate of 10° F./second or less. Most preferred zone residence times are less than 5 seconds with heat rates of 5° F./second or less.
Heating rate control can be accomplished by any number of methods that may depend on whether the dryer design is for a new build or for the modification of an existing design. Examples of temperature profile control include: 1) Mixing of cooler air in variable amounts along the length of the zone; 2) By adding internal duct heaters in the dryer air nozzle feeds; 3) Installing radiant heaters between the air bars; or 4) any combination of the above.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated in the accompanying drawings, in which like reference numerals are used to denote like or similar parts, and wherein:
FIG. 1 shows the volume residual solvent left on the photoreceptor belt as it passes through the apparatus of the prior art;
FIG. 2 shows the web temperature profile as the web passes though the apparatus of the prior art;
FIG. 3 shows the web heating rate profile as the web passes through the apparatus of the prior art;
FIG. 4 shows the boiling point of the coating and the web temperature as it passes through the apparatus of the prior art;
FIG. 5 shows the zone temperature profile for an arch type dryer with zone transition heating rates of 5° F./second or less;
FIG. 6 shows the residual solvent profile for an arch type dryer with zone transition heating rates of 5° F./second or less;
FIG. 7 is a top view of a dryer apparatus of the first preferred embodiment which has end fed nozzles;
FIG. 8 is a side view of the dryer apparatus which has end fed nozzles;
FIG. 9 is a top view of the dryer apparatus of the second preferred embodiment which has center fed air nozzles; and
FIG. 10 is a side view of the dryer apparatus which has center fed air nozzles.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Drying a polymer-solvent solution is strongly affected by the variation of diffusivity, solvent vapor pressure and solvent activity with temperature and composition. The sensitivity of the drying characteristics to the diffusion coefficients is affected by their dependence on solvent concentration and ambient temperature. In polymeric solutions, diffusion coefficients will generally drop as the concentration of solvents decreases, the temperature decreases and/or the molecular weight of the polymers increases. The latent heat of vaporization acts as a heat sink at the upper surface of the film, causing a significant evaporative cooling in the early stages of the drying. This region is commonly known as the constant rate drying regime.
As the solvent concentration reduces, the limiting factor of the drying rate is the rapidly falling diffusion coefficients. When the solvent concentration is sufficiently reduced, the drying process enters what is known as the diffusion controlled regime. In the diffusion controlled regime, the strong dependence of the diffusion coefficient on solvent concentration causes the drying rate to drop sharply when the solvent level is reduced. Thus, the residual volume of solvent essentially levels off in the latter zones, slowing the removal of additional solvent. In this regime, the residual solvent concentration depends mainly on the temperature of the zone. Thus, higher temperatures are necessary to remove more solvent.
In addition, during the diffusion controlled phase of drying within a particular temperature zone, two distinct drying regions (or periods) occur. In the first period, the web temperature is changing and the solvent removal rate is relatively high. In the second period, the web temperature is in equilibrium with the dryer temperature and the solvent removal rate is very low. The difference in drying rate between these two periods can be dramatic, with up to 90% or more of the solvent loss within each temperature zone occurring during the first period. This is significant because the first period typically occupies only a small fraction of the total length of the temperature zone and it follows that the zone is too long for economically efficient drying.
An example of the drying process described above is shown in FIGS. 1 and 2. FIG. 1 shows a diagram of the residual solvent in a multizone dryer and a corresponding diagram of the web temperature is shown in FIG. 2. By comparing FIGS. 1 and 2, it can be seen that the solvent evaporates at a useful rate only when the temperature of coating is changing. Once the temperature of the polymer-solvent is constant, the drying process essentially stops. Therefore, the rest of the time spent in the drying zone accomplishes little. Note from FIG. 1, 80 to 99% of the solvent removal is occurring in the first 10 to 20% of each zone.
One consequence of this type of drying is that, the exit temperature of the dryer becomes essentially fixed by residual solvent specifications. The solvent is effectively removed only when the substrate temperature increases. Solvent removal during the second drying period of the drying zone is slow and contributes little to residual solvent reduction. From FIGS. 1 and 2, it follows that the optimum dryer design (i.e. shortest dryer) will have a continuous temperature ramp during the diffusion controlled phase of drying.
An additional problem is boiling of the coating if the temperature differential between zones is too large and too abrupt. This has been demonstrated with an air flotation dryer design of the prior art.
FIG. 3 shows the substrate, or web, heating rate for the last three zones of a four zone air flotation dryer of the prior art. Note that heating rates of 20° F. to over 100° F. per second are achieved (typical for a dryer of this type).
FIG. 4 shows the coating average boiling point, also referred to as the bubble point, for the last three zones of the dryer. The bubble point temperatures are calculated from residual solvent measurements. The solid and dotted lines represent the dryer temperature in each temperature zone. The temperature is constant throughout each zone and increases sharply at the transition point between zones. The calculated boiling points of the coatings of two polymer-solvents are represented by individual points (circles and triangles) in FIG. 4.
In order to prevent small bubbles from forming on the web, the actual temperature of the coating must not exceed the bubble temperature of the solution at any time. Thus, the dryer temperature should always be less than the average bubble temperature of the coating. However, at the transition point between temperature zones in FIG. 4, the dryer temperature approaches or even exceeds the coating temperature. Therefore, such a dryer that has sharp increases in temperature between zones can and does cause the formation of bubbles in the coating.
In contrast, old style arch type dryers showed much lower heating rates (5° F. or less) between zones. The result was a much softer web temperature profile at the zone transitions. In these dryers, the web temperature did not exceed the coating boiling point at the zone transitions and bubble formation was eliminated. The problem with these dryers was that the length of the dryer had to be very long in order to increase the temperature of the solvent to the final temperature. Since these dryers were so long, they were inefficient and expensive.
Further, even in these old style arch dryers, residual solvent measurements, as shown in FIGS. 5 and 6, indicate that the evaporation of the solvent occurs at useful rates only in the transition regions where the temperature of the coating is changing. Again, the longer constant temperature portions of the zones were generally ineffective in removing solvent.
Accordingly, the ideal dryer should utilize a continuous temperature profile to apply the maximum end point temperature at the highest heating rate possible to the polymer-solvent without causing the formation of bubbles. This would allow for a shorter dryer and an increase in throughput without forming bubbles in the coating. Temperature or heating rate control of the diffusion controlled stages of the drying process for polymer solutions, e.g. a layer of polycarbonate/methylene chloride (also known as small molecular transport layer), is critical to accomplish this result. With air flotation dryers, heating rate control may be accomplished by the addition of numerous drying zones. Generally, these zones must be as short as possible. To be efficient, the amount of time that a portion of the substrate with the polymer-solution remains in a particular temperature zone should be less than 5 seconds. Alternatively, supplemental heating rate control (temperature profiles) could be attained by the use of piped or ducted concurrent air flow or radiant heating installed in each dryer zone. A dryer should be capable of producing heating rates of less than 10° F. per second at the zone transitions (with heating rates less than 5° F. per second preferred.)
The preferred embodiments of the present invention use very short temperature zones (low overall heating rates.) A continuous or nearly continuous change in temperature profile is generated. The preferred embodiments use zones which are shorter than the typical length in the prior art dryers. The amount of time that a portion of the substrate with the polymer-solution remains in a particular temperature zone should range from 1 second to less than 10 seconds with residence times of less than 5 seconds most preferred.
The first preferred embodiment of the invention is shown in FIGS. 7 and 8. A top view of a dryer with end fed air nozzles is shown in FIG. 7. An air intake duct 100 has air forced in the direction of arrow 102 from an intake air source (not shown). The temperature of this air is lower than the bubble point of the solvent. The air can be filtered and compressed in the manufacturing plant or even a low pressure ducted air could be used.
The air is passed through the duct 100 into manifolds 104 and 106 where the air moves down the length of the manifold in the direction of the arrows 102. The substrate 114 carries a polymer-solvent layer, which was applied by a coater (not shown) before entering the dryer. The substrate 114 moves in the direction of arrow 118. Air is forced through the manifolds 104 and 106 into the air impingement nozzles 108 which are spaced along the full length of the dryer. Coanda nozzles can be used instead of impingement nozzles.
As the air moves through the manifold 106 in the downstream direction, it passes several resistive heaters (electrical heaters) 110. The temperature of the air increases as it passes each of the resistive heaters 110. Thermocouples 112 are used between the resistive heaters 110. A computer (not shown) monitors the voltage across the thermocouples 112 (which varies as a function of the temperature of the thermocouple) and determines whether the output of resistive heaters 110 should be changed to increase or decrease the temperature of the air. Another method is to connect the thermocouple 112 to a resistive heater 110 in series with a constant power supply. As the temperature of the air increases, the thermocouple's resistance increases which decreases the voltage across the resistive heater 110. The resistive heater generates less heat so that the temperature of the air begins to lower.
Accordingly, as the substrate 114 passes each of the air impingement nozzles 108, a stream of air at varying temperatures is applied across the width of the substrate 114.
A preferred modification injects cool air into the nozzle arrangement by adding, within a nozzle 108, a means of transporting cool air along the cross-sectional width of the dryer nozzle. This could be accomplished by using additional piping or ducting. If compressed air were to be used, standard piping or tubing could be set within the nozzle and cool air flow rates adjusted by varying air pressure in the injection mechanism. Control is achieved through the use of a temperature sensing element feedback in the pressure regulator or flow regulator. The addition of a fan with a concurrent ducting and variable air volume control could be used with little or no disruption of the existing methods of air transport throughout a zone. Mixing of the air streams could be performed inside the air nozzle in order to prevent alternating periods of very hot air followed by cool air. In the alternative, placement of the duct work could be within the area normally used for exhausting and recirculation of zone air.
A side view of the dryer with end-fed air nozzles is shown in FIG. 8. In this configuration, there are air nozzles 108 providing air to the top portion of the substrate 114 and the bottom portion of the substrate 114. Air supply lines 116 connect the manifolds 104 and 106 to the air impingement nozzles 108. The distance between a nozzle 108 and the substrate 114 is determined by the polymer-solvent being used, in order to have maximum drying to occur. In this configuration, the resistive heater elements 110 and temperature sensing element 112 are present in both the top portion and the bottom portion of the dryer to independently control the temperature of the air applied to the top and bottom of the substrate, respectively.
A second preferred embodiment of the present invention is shown in FIGS. 9 and 10. This embodiment uses center-fed air nozzles. An air intake duct 200 allows compressed, cooled and filtered air to move in the direction of arrow 202. The air travels down manifolds 204 and 206 which are centrally positioned over the nozzles 208. The manifolds 204 and 106 direct the air to the end of the dryer so that even pressure is applied throughout the dryer. Air impingement nozzles 208, as in the first preferred embodiment, run the full width of the substrate 214. The substrate 214 moves in the direction of arrow 218, encountering first the nozzles 208 containing cool air and progressively encountering nozzles 208 containing progressively hotter heated air. Air in the manifold 206 passes resistive heaters 210 and the temperature sensing element 212. As in the first preferred embodiment, temperature sensing is used to monitor the internal air temperature near the resistive heaters 210 to control the resistive heaters 210, thereby controlling the temperature of the air being applied to the polymer-solvent on the substrate 214. This system could also utilize a cool air injection and control system as described in the first preferred embodiment.
A side view of a dryer with center-fed air nozzles is shown in FIG. 10. There are two complete sets of manifolds 204 and 206, resistive heaters 210, thermocouples 212 and impingement nozzles 208. In this second preferred embodiment, similar to the first preferred embodiment, the heated air is applied to the top portion and bottom portion of the substrate 214. Air supply lines 216 supply air from the manifolds 204 and 206 to the air impingement nozzles 208. However, a dryer may have components to apply the heated air to only one side of the substrate 214.
Several modifications can be made to the previous embodiments, which would assist in temperature control of the temperature zones. A first modification incorporates refrigeration coils in the manifold 104 and 204. The coils would be energized to make the air progressively colder as it moves away from the air duct 100 and 200, respectively.
A second modification positions the air duct 100 at the end of manifold 104, where the substrate 114 enters the dryer. Resistive heaters 110 and thermocouples 112 could be placed along the full length of the manifolds 104 and 106 to heat the air to its final temperature at the last nozzle 108 of the dryer.
A third modification would place IR (radiant) heaters internally between the air nozzles inside the dryer to heat the web directly.
These preferred embodiments can be modified to be used with any process that involves the drying of any coated polymer-solvent layers including: polymer film casting; protective overcoating; package coating; paper overcoating; transparency coating, etc. Polymer film casting is a process in which a polymer webstock, usually 0.0005 to 0.010 inch thick, is formed by coating a polymer-solvent solution on a metal support. After a "green set time" where the solution sets, the coating is then peeled off and dried.
Although the invention has been described and illustrated with particularity, it is intended to be illustrative of preferred embodiments and understood that the present disclosure has been made by way of example only, and numerous changes in the combination and arrangements of the parts and features can be made by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter claimed. | A dryer with zone temperature controls for drying thick polymer-solvent layers on a substrate. The dryer is formed with several heating elements located in an air duct. The cool air is heated a specific amount as it passes each heating element. The heated air is then applied to the polymer-solvent solution on the substrate in a continuous fashion so that the polymer-solvent solution slowly heats up as it passes through the drying apparatus. The preferred design is to ensure a zone residence time of less than 10 seconds and a web heating rate of 10° F./second or less. Most preferred design is a zone residence time less than 5 seconds and a heating rate less that 5° F./second. The dryer is designed to have a continuous temperature gradient, especially in the critical later stages of drying when the solvent content of the film is less than 20%. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to an FM receiver in which electric power consumption can be reduced.
BACKGROUND OF THE INVENTION
[0002] Conventionally, in an FM receiver as shown in FIG. 1 , FM radio waves are received by an antenna unit (not shown), prescribed detection processes are conducted in an FM detector unit 51 , and stereophonic demodulation processes are conducted in a stereophonic demodulator unit 52 comprising a stereophonic demodulator circuit, a 38 kHz stereophonic generator circuit and a pilot signal detector circuit. Then, a signal which has been subject to the stereophonic demodulation is output as audio information via an output buffer 53 .
[0003] The FM receiver as above is used by being switched between stereophonic and monophonic. However, even when monophonic output is produced, signals are transmitted through the stereophonic demodulator unit, accordingly, electric power is consumed by the stereophonic demodulator unit in vain.
[0004] As for a method of efficiently reducing electric power consumption, a receiver is disclosed in the Patent Document 1 below, for example, in which receiving operations are continued for a prescribed time period from a reception start time to a reception end time when a reception start time of signals is known in advance.
[0005] In this receiver, a power source is turned on around the above reception start time, signals are generated which only activate necessary units in accordance with respective stages of reception operations until the reception is completed, and electric power can be supplied to units which need electric power in respective stages based on the above signals, so that electric power consumption is reduced.
[0006] Patent Document 1: Japanese Patent Application Publication No. 10-70500 “Receiver”
[0007] However, the technique in the above Patent Document 1 can only be applied when information such as a reception start time, a reception end time or the like is known in advance, and it is impossible to reduce electric power consumption by directly applying this technique to an FM receiver in which switching can be conducted between stereophonic and monophonic.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide an FM receiver which can be used by being switched between stereophonic and monophonic, in which electric power consumption can be reduced.
[0009] An FM receiver according to an aspect of the present invention is an FM receiver which can be used by being switched between stereophonic and monophonic, comprising detecting unit for detecting a received signal, switching unit for selecting either one of a route via a stereophonic demodulator unit and a route bypassing the stereophonic demodulator unit upon transmitting the detected signal to an output buffer, based on a control signal indicating the selection of either one of the stereophonic and the monophonic, in which electric power supply to the stereophonic demodulator unit is turned off based on the control signal when the route bypassing the stereophonic demodulator unit is selected.
[0010] Based on the above, when the monophonic mode is selected, the route bypassing the stereophonic demodulator unit is selected, and also, electric power supply to the stereophonic demodulator unit which is not used is turned off, accordingly, electric power consumption is reduced.
[0011] The above switching between the stereophonic and monophonic can be conducted in accordance with an external switching instruction provided by a user.
[0012] Also, the above comparison between stereophonic and monophonic can be conducted by further comprising comparison unit for comparing a strength of the received signal with a reference value, and the switching unit can select the route via the stereophonic demodulator unit when the received signal is higher than the reference value, and/or select the route bypassing the stereophonic demodulator unit when the received signal is equal to or lower than the reference value, based on an output signal of the comparison unit.
[0013] In both of the above cases, the stereophonic demodulator unit turns off electric power supply to the stereophonic demodulator unit when the route via the stereophonic demodulator unit is selected, based on the switching instruction provided by the user or the output signal of the comparison unit.
[0014] Also, when the switches are arranged after a branch of the route via the stereophonic demodulator unit and the route bypassing the stereophonic demodulator unit and close to the branch, and also, are arranged before a joining point of the route via the stereophonic demodulator unit and the route bypassing the stereophonic demodulator unit and close to the joining point, the number of circuit portions (sections) over which unnecessary propagation of signals occurs can be reduced so that factors deteriorating the stability of operation of the circuit can be reduced.
[0015] According to the FM receiver of the present invention, when a monophonic mode is selected, the route bypassing the stereophonic demodulator unit is selected and also, electric power supply to the stereophonic demodulator unit which is not used is turned off so that electric power consumption is reduced.
[0016] Also, when the switches are arranged after a branch into the route via the stereophonic demodulator unit and the route bypassing the stereophonic demodulator unit and close to the branch, and also, are arranged before a joining point of the route via the stereophonic demodulator unit and the route bypassing the stereophonic demodulator unit and close to the joining point, the number of circuit portions (sections) over which unnecessary propagation of signals occurs can be reduced so that factors deteriorating the stability of operation of the circuit can be reduced.
[0017] Also, in the FM receiver according to the present invention, because the stereophonic demodulator unit is bypassed by selecting routes between the case of outputting monophonic audio and the case of outputting stereophonic audio, accordingly, deterioration in signals when the monophonic output is desired is reduced so that audio quality can be improved, compared to the case where the monophonic audio and the stereophonic audio are output via the same route, i.e., the case of a conventional example without the route selection.
BRIEF DESCRIPTION OF DRAWINGS
[0018] FIG. 1 is a block diagram for showing an example of a configuration of a conventional FM receiver;
[0019] FIG. 2 is a block diagram for showing a configuration of an FM receiver according to the present embodiment;
[0020] FIG. 3 is a block diagram for showing an alternative of the FM receiver according to the present embodiment;
[0021] FIG. 4A shows a specific circuit configuration of one of switches 13 b and 17 b in FIG. 3 ;
[0022] FIG. 4B shows a specific circuit configuration of one of switches 13 a and 17 a in FIG. 3 ;
[0023] FIG. 5 is a first diagram for showing a circuit configuration of a principal unit related to electric power supply to a stereophonic demodulator unit;
[0024] FIG. 6 is a second diagram for showing a circuit configuration of a principal unit related to electric power supply to the stereophonic demodulator unit;
[0025] FIG. 7 is a block diagram for showing a second alternative of the FM receiver according to the present embodiment;
[0026] FIG. 8A is a diagram for explaining positions at which switches are arranged, and shows the case where the switches are arranged only at a point close to a branch on the route via the stereophonic demodulator unit and at a point close to the branch on the route bypassing the stereophonic demodulator unit; and
[0027] FIG. 8B is a diagram for explaining positions at which switches are arranged, and shows the case where the switches are arranged at points respectively close to both of the branch and the joining point on the route via the stereophonic demodulator unit and the route bypassing the stereophonic demodulator unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Hereinafter, embodiments of the present invention will be explained in detail by referring to the drawings.
[0029] FIG. 2 is a block diagram for showing a configuration of an FM receiver according to the present embodiment. Additionally, at least some of the components in FIG. 2 , for example switches 13 and 17 , a stereophonic demodulator unit 15 , a route 1 and a route 2 , are mounted on a semiconductor integrated circuit substrate which is produced by a CMOS process that can form a P-channel MOS transistor and an N-channel MOS transistor.
[0030] In FIG. 2 , the FM receiver according to the present embodiment comprises an FM detector unit 11 , the switches 13 and 17 , the stereophonic demodulator unit 15 and an output buffer 19 .
[0031] Hereinafter, operations of the FM receiver will be explained.
[0032] First, FM radio waves are received by an antenna (not shown), and a detection process is conducted by an FM detector unit 11 . A switch 13 provided at a later stage of the FM detector unit 11 selectively switches between a route 1 and a route 2 in the figure based on an instruction of a user of the FM receiver such as pressing of buttons on a surface of the receiver. The above route 2 is a route via the stereophonic demodulator unit 15 , and the route 1 is a route which bypasses the stereophonic demodulator unit 15 .
[0033] Audio which is to be output via the output buffer 19 based on the above instruction by the user is switched from stereophonic output to monophonic output, or conversely, from monophonic output to stereophonic output. This instruction of the user is input to the switch 13 , the stereophonic demodulator unit 15 and the switch 17 as a power enable signal specifying whether the stereophonic output is conducted or the monophonic output is conducted.
[0034] When a user does not need the stereophonic output such as in a case where it is desired that the receiver is used for a long time based on electric power supplied by a battery, or reception conditions are bad, the user provides an instruction to switch to a monophonic mode, and a route of a detected signal is switched from a route 2 via the stereophonic demodulator unit 15 to a route 1 bypassing the stereophonic demodulator unit 15 in accordance with a power enable signal specifying contents of the instruction. When the route bypassing the stereophonic demodulator unit 15 is selected, electric power supply to the stereophonic modulator unit 15 is turned off in accordance with the above power enable signal so that reduced electric power consumption is realized.
[0035] Additionally, when the user provides an instruction to switch to a stereophonic mode, the route of the detected signal is switched from the route 1 bypassing the stereophonic demodulator unit 15 to the route 2 via the stereophonic demodulator unit 15 in accordance with a power enable signal specifying contents of the instruction. When the route via the stereophonic demodulator unit 15 is selected, electric power supply to the stereophonic modulator unit 15 is turned on in accordance with the above power enable signal.
[0036] FIG. 3 is a block diagram for showing an alternative of the FM receiver according to the present embodiment.
[0037] In this alternative embodiment, the switching which has been conducted based on the instruction provided by the user in the first embodiment is automatically conducted based on the strength of a received signal.
[0038] In FIG. 3 , in the FM receiver, information specifying reception strength of the received signal such as, for example, an RSSI voltage, is output by a limiter 21 , and the output information is input to one input of a 2-input comparator 22 . To the other input of the comparator 22 , a reference value (reference voltage) is input, and the above RSSI voltage and the reference voltage are compared by the comparator 22 . A comparison result signal SW specifying the comparison result is output by the comparator 22 , and the comparison result signal SW and an inverted signal thereof are input to switches 13 a , 13 b , 17 a , 17 b and the stereophonic demodulator unit 15 via an inverter 23 provided at a later stage to the comparator 22 . Additionally, in the present alternative embodiment, when the above value specifying the reception strength is lower than the reference value, switching is conducted to a monophonic mode.
[0039] FIG. 4A and FIG. 4B are circuit diagrams for showing specific configurations of the switches. FIG. 4A shows the following switches 13 b and 17 b and FIG. 4B shows the following switches 13 a and 17 a respectively.
[0040] FIG. 4A specifically shows circuit configurations of the switches 13 b and 17 b . The above switches each comprise two control terminals for inputting the comparison result signal SW and the inverted signal thereof. And, switching of whether or not a signal of an input (in) side is allowed to pass to an output (out) side is conducted in accordance with values input to the control terminals. Because the switches 13 b and 17 b are provided on a route via the stereophonic demodulator circuit, the configuration in the figure assumes the case in which the comparison result signal SW of the comparator 22 is set to “H” and accordingly, the inverted signal thereof is set to “L” when the reception strength is higher than the reference value. With the comparison result signal SW and the inverted signal thereof as above, the switches 13 b and 17 b in FIG. 3 are turned on (become continuous) and the switches 13 a and 17 a are turned off (become discontinuous), and the signal passes on the route via the stereophonic demodulator unit 15 .
[0041] FIG. 4B specifically shows circuit configurations of the switches 13 a and 17 a . The above switches each comprise two control terminals for inputting the comparison result signal SW and the inverted signal thereof. And, switching of whether or not a signal on an input (in) side is allowed to pass to an output (out) side is conducted in accordance with values input to the control terminals. Because the switches 13 a and 17 a are provided on a route bypassing the stereophonic demodulator circuit, the configuration in the figure assumes the case in which the comparison result signal SW of the comparator 22 is set to “L” and accordingly, the inverted signal thereof is set to “H” when the reception strength is equal to or lower than the reference value. With the comparison result signal SW and the inverted signal thereof as above, the switches 13 a and 17 a in FIG. 3 are turned on (become continuous) and the switches 13 b and 17 b are turned off (become discontinuous), and the signal passes on the route bypassing the stereophonic demodulator unit 15 .
[0042] Additionally, as the switches 13 and 17 , semiconductor switching elements such as MOS transistors or the like, as shown in FIG. 4A or 4 B can be employed, however, other types of switches such as mechanical switches for example can also be employed.
[0043] FIG. 5 is a first diagram for showing a circuit configuration of a principal unit related to electric power supply to the stereophonic demodulator unit.
[0044] In FIG. 5 , the principal unit related to the electric power supply to the stereophonic demodulator unit comprises, together with a main power supply 31 , a first transistor group consisting of transistors 32 , 33 and 34 , and a second transistor group consisting of transistors 36 , 37 and 38 . As shown, the transistors 32 , 33 and 34 are P-channel transistors, and are provided on a first direct current electrical potential side (VDD side). The transistors 36 , 37 and 38 are N-channel transistors, and are provided on a second direct current electrical potential side (ground side). Additionally, the comparison result signal SW and the inverted signal of the comparison result signal SW are applied respectively to a gate of the transistor 32 and a gate of the transistor 36 .
[0045] Hereinafter, a control upon turning off electric power supply in the principal unit in the above configuration will be explained.
[0046] In FIG. 5 , when the inverted signal of “H” of the comparison result signal SW is applied to the gate of the transistor 36 provided on the second direct current electrical potential side (ground side) in the case when the above comparison result signal SW is “L”, the transistor 36 is turned ON (continuous) because the transistor 36 is an N-channel transistor, and referring to the above second direct current electrical potential, “L” is applied to the gate of the transistor 37 , which is the other of the transistors forming a differential pair with the above transistor 36 and which is provided on the same second direct current electrical potential side and/or to the gate of the transistor 38 provided on the same second direct current electrical potential side. As a result, the transistor 37 and the transistor 38 are turned off (discontinuous).
[0047] Also, when a comparison result signal SW “L” is applied to a gate of the transistor 32 provided on the first direct current electrical potential side (VDD side), the transistor 32 is turned ON because the transistor 32 is a P-channel transistor, and referring to the above first direct current electrical potential, “H” is applied to the gate of the transistor 33 , which is the other of the transistors forming a differential pair with the above transistor 32 and which is provided on the same first direct current electrical potential side and/or to a gate of the transistor 34 provided on the same first direct current electrical potential side. As a result, the transistor 33 and the transistor 34 are turned off (discontinuous). In the figure, the transistor 34 constitutes a first stage of a multistage transistor circuit for example, and by turning off this transistor 34 , electric current is prevented from flowing through subsequent circuit portions so that electric power consumption can be reduced.
[0048] Additionally, in the stereophonic demodulator unit in FIG. 5 , the switching regarding on and off of the electric power supply to the stereophonic demodulator unit is conducted by inputting both the comparison result signal SW and the inverted signal thereof. However, it is also possible to conduct switching regarding on and off of the electric power supply based on either one of the above signals. A configuration example of such a stereophonic demodulator unit is shown in FIG. 6 .
[0049] In FIG. 6 , when the inverted signal “H” of the comparison result signal SW is applied to a gate of the transistor 46 provided on the second direct current electrical potential side (ground side) in the case when the comparison result signal SW is “L”, the transistor 46 is turned ON (continuous) because the transistor 46 is an N-channel transistor, and referring to the above second direct current electrical potential, “L” is applied to the gate of the transistor 47 which is the other of the transistors forming a differential pair with the above transistor 46 and which is provided on the same second direct current electrical potential side and/or to a gate of the transistor 48 provided on the same second direct current electrical potential side. As a result, the transistor 47 and the transistor 48 are turned off (discontinuous). In the figure, the transistor 48 constitutes a first stage of a multistage transistor circuit for example, and by turning off this transistor 48 , electric current is prevented from flowing through subsequent circuit portions so that electric power consumption can be reduced.
[0050] The circuit configuration of the stereophonic demodulator units in FIG. 5 and FIG. 6 are examples. In these configurations, by providing signals to the upstream transistors constituting multiple stages (the transistors 32 and 36 in FIG. 5 , the transistor 46 in FIG. 6 ), causing these transistors to be continuous, the transistor which is the other of the transistors forming each differential pair with the transistor (the transistors 33 and 37 in FIG. 5 , the transistor 47 in FIG. 6 ) can be turned off.
[0051] As above, in the present embodiment, when the route bypassing the stereophonic demodulator unit is selected, electric power supply to the stereophonic demodulator unit is turned off, accordingly, electric power consumption can be reduced.
[0052] Additionally, as a configuration of the stereophonic demodulator unit, an arbitrary configuration that allows switching between ON and OFF of electric power supply by a control of the FM receiver according to the present invention can be employed besides those shown in FIG. 5 and FIG. 6 .
[0053] FIG. 7 is a block diagram for showing a second alternative of the FM receiver according to the present embodiment. In this second alternative embodiment, the switch can respond to a MUTE instruction provided by a user.
[0054] In FIG. 7 , in the FM receiver, information specifying reception strength of the received signal such as, for example, an RSSI voltage, is output by the limiter 21 , and the output information is input to one input of the 2-input comparator 22 . To the other input of the comparator 22 , a reference value (reference voltage) is input, and the above RSSI voltage and the reference voltage are compared by the comparator 22 . The comparison result signal SW specifying the comparison result is output by the comparator 22 , and is input via one of inputs (terminals) of a 2-input and 4-output selector 24 provided at a later stage than the comparator 22 . To the other input (terminal) of the selector 24 , a signal (MUTE signal) specifying a MUTE instruction (an instruction not to output audio) provided by a user is input.
[0055] The selector 24 receives the above two inputs, generates output signals as below and transfers them to the respective switches and stereophonic demodulator unit.
[0000] 1. A→L, B→L regardless of the value of the comparison result signal SW, when the MUTE signal is ON (MUTE instruction is provided)
2. A→H, B→L when the MUTE signal is OFF and the comparison result signal SW specifies monophonic
3. A→L, B→H when the MUTE signal is OFF and the comparison result signal SW specifies stereophonic
[0056] Hereinafter, respective cases will be explained.
[0057] When the MUTE instruction is provided by a user, signals of A→L and B→L are output by the above selector 24 . As a result, to the control terminals of the switches 13 a and 17 a are input the signal A (L) and the inverted signal (H) of the signal A, and the switches 13 a and 17 a are turned off. Also, to the control terminals of the switches 13 b and 17 b are input the signal B (L) and the inverted signal (H) of the signal B, and the switches 13 b and 17 b are turned off. Also, to the stereophonic demodulator unit 15 is input the signal B (L), and the inverted signal (H) of the signal B, and thereby, electric power supply to the stereophonic demodulator unit 15 is cut. As above, when the MUTE instruction is provided, the switches 13 b and 17 b on the route via the stereo demodulator unit 15 and the switches 13 a and 17 a on the route bypassing the stereophonic demodulator unit 15 are turned off and also, electric power supply to the stereophonic demodulator unit 15 is turned off.
[0058] When the MUTE instruction is not provided and an instruction to switch to a monophonic mode is provided (or automatic switching to a monophonic mode occurs), signals of A→H and B→L are output from the above selector 24 . As a result, to the control terminals of the switches 13 a and 17 a are input the signal A (H) and the inverted signal (L) of the signal A, and the switches 13 a and 17 a are turned on. Also, to the control terminals of the switches 13 b and 17 b are input the signal B (L) and the inverted signal (H) of the signal B, and the switches 13 b and 17 b are turned off. Also, to the stereophonic demodulator unit 15 is input the signal B (L), and the inverted signal (H) of the signal B, and thereby, electric power supply to the stereophonic demodulator unit is cut. As above, when the instruction to switch to a monophonic mode is provided (or automatic switching to a monophonic mode occurs), the switches 13 b and 17 b on the route via the stereophonic demodulator unit 15 are turned off, and the switches 13 a and 17 a on the route bypassing the stereophonic demodulator unit 15 are turned on, and also, electric power supply to the stereophonic demodulator unit 15 is turned off.
[0059] When the MUTE instruction is not provided and an instruction to switch to a stereophonic mode is provided (or automatic switching to a stereophonic mode occurs), signals of A→L and B→H are output from the above selector 24 . As a result, to the control terminals of the switches 13 a and 17 a are input the signal A (L) and the inverted signal (H) of the signal A, and the switches 13 a and 17 a are turned off. Also, to the control terminals of the switches 13 b and 17 b are input the signal B (H) and the inverted signal (L) of the signal B, and the switches 13 b and 17 b are turned on. Also, to the stereophonic demodulator unit 15 is input the signal B (H), and the inverted signal (L) of the signal B, and thereby, electric power supply is turned on. As above, when the instruction to switch to a stereophonic mode is provided (or automatic switching to a stereophonic mode occurs), the switches 13 b and 17 b on the route via the stereophonic demodulator unit 15 are turned on, and the switches 13 a and 17 a on the route bypassing the stereophonic demodulator unit 15 are turned off, and also, electric power supply to the stereophonic demodulator unit 15 is turned on.
[0060] Additionally, in FIG. 7 , switching between stereophonic and monophonic is automatically conducted based on a determination of the comparator, however, it is needless to mention that even when the switching between stereophonic and monophonic is conducted based on an instruction of a user, the switch can be similarly constituted with an added MUTE function.
[0061] Additionally, in the above explanation, the switches are arranged after a branch into a route via the stereophonic demodulator unit and a route bypassing the stereophonic demodulator unit and before a joining point of the above two routes, however, the switch may be arranged either after a branch or before a joining point. However, it is desirable that the switches are arranged at both a point which is after the branch and which is as close to the branch as possible, or a point which is before the joining point and which is as close to the joining point as possible.
[0062] FIG. 8A and FIG. 8B are diagrams for explaining positions at which the switches are arranged. FIG. 8A shows the case where the switches are arranged only at a point close to a branch on the route via the stereophonic demodulator unit and at a point close to the branch on the route bypassing the stereophonic demodulator unit. FIG. 8B shows the case where the switches are arranged at points close to both the branch and the joining point respectively on the above two routes.
[0063] In FIG. 8A , a detected signal S 1 is branched into a signal S 2 and a signal S 3 at a branching point P 1 . In the figure, the case where the route via the stereophonic demodulator unit is selected is assumed, therefore, the signal S 3 reaches a joining point P 2 via the switch 13 b and the stereophonic demodulator unit 15 . At the joining point P 2 , the signal S 3 is branched into a signal S 4 transmitted to an output buffer provided at a later stage and into a signal S 5 propagating along the route for a monophonic signal in the backward direction. The above propagation of the signal S 5 in the backward direction along the route for the monophonic direction further causes propagation along the same route in the forward direction because the switch 13 a in an off state functions as a barrier, which can be a factor in causing deterioration of the stability of operation of the circuit. Generally, a section over which the signal S 2 and signal S 5 in the figure propagate i.e., the section denoted by X and the section denoted by Y (section X+Y) are subject to the occurrence of propagation of unnecessary signals as above. Additionally, as is obvious from the above explanation, the length of the section X+Y over which the above unnecessary signal propagates basically does not change in the case where a switch is arranged at one point on each route.
[0064] Meanwhile, when the switches 13 a , 13 b , 17 a and 17 b are respectively arranged after the branching point P 1 and before the joining point P 2 , the detected signal S 1 is branched into the signal S 2 and the signal S 3 at the branching point P 1 . The signal S 3 reaches the joining point P 2 via the switch 13 b , the stereophonic demodulator unit 15 and the switch 17 b . At the joining point P 2 , the signal S 3 is branched into the signal S 4 transmitted to the output buffer provided at a later stage, and into the signal S 5 which propagates along the route for the monophonic signal in the backward direction. The sum X+Y of sections over which unnecessary signals propagate in the circuit is greatly reduced compared to the configuration shown in FIG. 8A , and the above factor deteriorating the stability of the operation of the circuit, is reduced in proportion to the amount the above sum is reduced. Additionally, in this regard, it is desirable that the positions after the branch at which the switches 13 a and 13 b are arranged are as close to the branch as possible, as long as necessary requirements regarding design are satisfied. Additionally, it is desirable that the positions before the joining point at which the switches 17 a and 17 b are arranged are as close to the joining point as possible, as long as necessary requirements regarding design are satisfied.
[0065] Additionally, in the FM receiver according to the present embodiment, routes are selected between the case of outputting monophonic audio and the case of outputting stereophonic audio, accordingly, deterioration in signals when the monophonic output is desired is reduced so that audio quality can be improved compared to the case where the monophonic audio and the stereophonic audio are output via the same route, i.e., as in the case of the conventional example without the route selection. This is because the stereophonic demodulator unit is bypassed upon the monophonic output and thereby deterioration in signals that occurs when the signals are transmitted through the stereophonic demodulator unit is suppressed.
APPLICABILITY TO INDUSTRIES
[0066] The present invention can be applied to an FM receiver in which switching between stereophonic and monophonic can be conducted. | An FM receiver which can be used by being switched between stereophonic and monophonic, and comprises detecting unit for detecting a received signal, two routes over which a detected signal is transmitted to an output buffer, and a switching unit for selecting either one of the two routes. The two routes consist of a route passing through a stereophonic demodulator unit and a route bypassing the stereophonic demodulator unit; and the switching unit selects either one of the two routes based on a control signal indicating the selection of either one of stereophonic and monophonic, and, when the route bypassing the stereophonic demodulator unit is selected, turns off power supply to the stereophonic demodulator unit based on the above control signal. | 8 |
RELATED APPLICATIONS
This is a continuation of application Ser. No. 08/757,559, filed Nov. 27, 1996, now U.S. Pat. No. 5,793,174, which claims priority to provisional application No. 60/025,541, filed Sep. 6, 1996.
TECHNICAL FIELD
This invention relates to electrically powered window coverings such as vertically adjustable shades, tiltable blinds and the like. More particularly, the invention relates to motorized window coverings which are activated by a wireless remote control transmitter and have associated with them a DC motor and electrical and mechanical circuitry adapted to store position information.
BACKGROUND
Wireless, remote control, motorized window coverings are activated by a control signal generated and sent by a transmitter. As explained in U.S. Pat. No. 4,712,104 to Kobayashi, the control signal is usually converted into one of audio, radio (RF), or light (either visible or, more preferably, infrared (IR)) energy, and transmitted through the air. When a button on a remote transmitter is pushed, the control signal comprising one of these types of energy is generated. The control signal sent by the transmitter may comprise a carrier signal which modulates either a continuous waveform or, more preferably, a sequence of spaced apart pulses. In those cases where spaced apart pulses are used, the pulses may either be coded, or they may comprise a sequence of pulses having substantially identical pulse widths and a constant pulse repetition frequency (PRF).
Each wireless, remote control motorized window covering system is provided with at least one transducer which converts the transmitted energy into electrical signals. In the case of an audio signal, the transducer is a microphone. In the case of RF signal, the transducer is likely to be an antenna, which may comprise an electromagnetic coil tuned to the carrier frequency. Finally, in the case of a light signal, the transducer is typically a photodiode, a photoresistor or a phototransistor.
As the signal travels from the transmitter to the transducer, it may become slightly corrupted. For instance, in the case of an acoustic signal, environmental noise in frequencies of interest, may be added to the signal. In the case of a light signal, light from other sources may be added to the received signal. Further corruption may take place as the transmitted signal is converted by the transducer into an electrical signal. This is because all transducers, however precise, cannot output an electrical signal which perfectly replicates the incoming transmitted signal. Usually, the electrical signal from the transducer will vary slightly from what was transmitted.
In addition to being corrupted, the signal may have also been modulated before transmission, as explained above. Together, these factors result in a signal that is distorted, and may be unintelligible to a decision circuit, described further below. To help correct some of this distortion, the electrical signal from the transducer is usually preprocessed before it is interpreted by a decision circuit. The goal of this preprocessing is to convert the electrical signal from the transducer to a form that can be used, and is less likely to be mis-interpreted, by the decision circuit. This process is loosely referred to as "cleaning up" the signal.
Cleaning up a signal from a transducer may involve filtering and demodulating a signal, as is often necessary with RF and IR signals. It may also involve waveshaping using comparators, inverters and triggers which have hysteresis-like input/output relationships, as disclosed in U.S. Pat. No. 5,275,219 and Canadian Patent No. 1,173,935 to Yamada, both of which are directed to motorized window systems which respond to daylight. In the case of IR signals, an integrated IR receiver, having a photodiode or a phototransistor, signal amplifiers, bandpass filters, demodulators, integrators and hysteresis-like comparators for waveshaping, perform such a function. The IS1U60, available from Sharp Electronics, is such a receiver, and can be used in remote control operations.
As stated above, in a remote control system, the cleaned up control signal is presented to a decision circuit. The role of the decision circuit is to determine a) whether the cleaned up control signal is valid, i.e., whether or not the signal content is such that the system should respond, and b) what, if any, response should be taken, in view of the control signal content and other status information.
The decision circuit comprises additional sensors, switches and registers, which keep track of such things as the direction of last motion, the position of the window covering relative to its travel extremes, and other status information. The decision circuit may be formed entirely from a combination of discrete analog and digital components, in which case the decision circuit is said to be hardwired. Alternatively, the decision circuit may include a microprocessor, microcontroller, or equivalent, in which case the decision circuit is said to be programmable. As is known to those skilled in the art, incorporating a microprocessor, or the like, allows for more complex decision making with the control signals and other status information.
All decision making circuits, whether or not they incorporate a microprocessor, are connected to a motor circuit adapted to drive a DC motor. Although the exact implementation of a motor circuit may differ, they all serve to connect the source of power, be it a battery, a solar cell, or even an AC-to-DC transformer, to the motor to operate the window covering. A typical motor circuit is disclosed in U.S. Pat. No. 4,618,804 to Iwasaki. In this circuit, two signals from the drive circuit are used to activate a pair of transistors. In such a motor circuit, upon receipt of an "UP" motor signal from the decision circuit, current flows from the voltage source, through a first transistor, the motor, and a second transistor to drive the motor in a first direction (e.g., clockwise). And, upon receipt of a "DOWN" motor signal, current flows from the voltage source through a third transistor, the motor, and a fourth transistor to drive the motor in an opposite direction (e.g., counterclockwise).
The power supply for a motorized window covering system may originate from an alternating current (AC) source, as shown in U.S. Pat. No. 3,809,143 to Ipekgil. In such case, one plugs into a wall socket and a transformer, or the like, is used to convert the AC into DC. As an alternative to using an AC power source, the power supply may comprise a battery, which may be recharged by a solar cell and/or by plugging into an AC source. U.S. Pat. No. 4,664,169 to Osaka discloses such a battery-operated lift system which moves a bottommost supporting slat relative to a headrail.
In wireless, remote-controlled motorized systems having an AC power source, there is little concern about designing the system to minimize energy consumption. This is because the AC source provides, for all practical purposes, virtually unlimited power. On the other hand, when a battery, especially one that cannot be recharged, is used, the current draw of the system becomes a design concern. This is because the transducer must always be available to receive a transmitted control signal. Also, the preprocessing, decision making and motor drive circuitry must be prepared to respond immediately, which usually means that they are, at the very least, in a "standby model", which also draws at least some current.
In the case of battery powered systems, there are three general approaches to conserving battery power. One approach is to use low-power, discrete analog and digital components which are on at all times, whether or not a valid control signal is received. This is the approach taken in U.S. Pat. No. 5,495,153 to Domel et al., which calls for using low dark-current phototransistors, and low-power logic devices such as NAND gates, counters, flip flops, power saving resistors, and the like. A second approach is to cycle one or more components on and off while waiting for a valid signal. This is the approach taken in U.S. Pat. No. 5,134,347 to Koleda, which calls for turning an IR receiver on for a brief period of time, and then allowing it continue to stay on longer if it receives a valid signal. The approach taken in Koleda is based on well-settled techniques for reducing the duty cycle of a receiver powered by a battery, as disclosed in U.S. Pat. No. 4,101,873 to Anderson et al. Finally, the third approach of conserving battery power is to use a solar cell to continuously recharge the batteries. U.S. Pat. No. 4,644,990 to Webb discloses a photosensitive energy conversion element which recharges batteries used to supply power to automatic system for tilting blinds.
To operate a window covering, the motor is typically placed in a headrail where it is hidden from view. A rod, to which the motor is operatively engaged, is rotatably mounted in the headrail. When the rod rotates, cords connected at one end to the rod, and also connected to the shade or blinds, can be wound either directly on the rod or on a spool arranged to turn with the rod in a lift system. U.S. Pat. No. 4,550,759 to Archer shows such a system for controlling the tilt of a blind, and U.S. Pat. No. 4,856,574 to Minami shows a motorized system for controlling the lift of a horizontal slat.
The extent of travel for a window covering can be limited by a counter, which uses dead reckoning to keep track of the number of rotations of the motor or the rod, relative to a stored counter value. In such case, the rotating wheel, or the like interrupts an optical or a magnetic path, and these interruptions are counted. Such systems are shown in the aforementioned Minami '574 reference.
As an alternative to "dead reckoning", limit switches may be used to control the extent of movement of the window covering. Limit switches are mechanical switches which are activated by engagement with a member of the system during the latter's operation. In the typical case, the limit switches are stationary and are abutted by a movable member of the motorized system. U.S. Pat. No. 4,727,918 to Schroeder discloses the use of limit switches in the headrail to control the tilt of a blind. Along similar lines, Danish patent No. 144,894 to Gross discloses the use of limit switches in the headrail to control the lift of a shade.
It should be noted here that we have used the word "shade" to generically describe a window covering which could be raised and lowered. This word encompasses such window coverings as venetian blinds comprising horizontal slats, pleated shades, accordion shades, and the like. As is known to those skilled in the art, pleated and accordion shades are typically formed from a lightweight fabric, and thus are often lighter than the more rigid slats. Because of this, it is generally accepted that mechanisms having sufficient torque to raise and lower horizontal slats, can also raise and lower lightweight shades.
Finally, in the typical remote control motorized system, the transducers, circuitry, motors, and servo mechanisms used to operate one type of window covering, can often be adapted to operate other types. For instance, as explained in International Publication WO 90/03060 to Roebuck, a motor/servo arrangement capable of opening and closing vertical slats and also drawing them, can readily be adapted to venetian blinds (horizontal slats) and the like. Similarly, EPO 381,643 to Archer shows that a DC motor mounted in headrail and connected to rotatably mounted rod can lift horizontal slats or pleated shades with virtually no modifications.
The prior art also includes systems which combine a large number of the features discussed above. For instance, there are wireless, remote-control lift systems having a headrail-mounted DC motor which winds a lift cord around a rod, and which has additional novel features. One such example is the battery-powered device of U.S. Pat. No. 5,029,428 to Hiraki, which is placed between the panes of a double-pane window. Another, is the IR-controlled, AC-powered, microprocessor-based device of Japanese Laid-open application 4-237790 to Minami, which provides for a programmable lower limit for the shade using the transmitter.
SUMMARY OF THE INVENTION
The present invention provides a battery-powered, wireless, remote-control, microprocessor-driven, motorized window covering assembly having the batteries, motor, drive gear, a rotatably mounted reel around which is lift cord is wound for raising and lowering a shade, circuitry and sensors, all housed in a headrail, making the resulting device more visually appealing.
One aspect of the invention is that the assembly's circuitry is configured to prolong the life of the batteries. In this regard, the IR receiver is alternately turned on and off in one of two power states which differ only in the length of the on-off power cycle. Peripheral sensors are also operated only on an as-needed basis, under microprocessor control to further prolong battery life. These sensors, along with flags, timers and registers controlled by the microprocessor, are arranged to restrict motor operation under inappropriate conditions, thereby both prolonging battery life and preventing damage to the assembly.
Another aspect of the present invention is that the assembly having a detector which engages the lift cord to determine when the shade has either been fully lowered, or alternatively, has met with an obstruction, the detector being used to control both the downward movement of the shade, and also the upper limit of shade travel, in conjunction with a remote control transmitter.
Yet another aspect of the present invention is a resilient, vibration dampening bushing which mounts the motor onto the head rail, thereby reducing vibrations transferred to the head rail and also to the rod. This not only helps dissipate energy imparted to the headrail, but also reduces annoying acoustic noise.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a window covering assembly in accordance with the present invention.
FIG. 2 is an end view of the assembly shown in FIG. 1.
FIG. 3 is a top view of the head rail.
FIG. 4 is a partially foreshortened front view of the assembly.
FIG. 5 is a sectional view taken along line 5--5 in FIG. 3.
FIG. 6 is a sectional view taken along line 6--6 in FIG. 3.
FIG. 7 is a perspective view of the lift cord which engages the reed switch.
FIG. 8 is a perspective view of the assembly of FIG. 1, with the front panel raised.
FIG. 9 is an enlarged perspective view of the motor and transmission assembly and mounting therefor.
FIG. 10 is a side elevation view of the mounting bushing shown in FIG. 9.
FIG. 11 is a front elevation view of the mounting bushing shown in FIG. 10.
FIG. 12 is a perspective view of a drive rod including a counter wheel.
FIG. 13 is a block diagram of a control circuit utilized in the present invention.
FIG. 14 is a circuit diagram of the power supply of FIG. 13.
FIG. 15 is a circuit diagram of the processor connections.
FIG. 16 is a circuit diagram of the interface module.
FIG. 17 is a circuit diagram of the sensor subcircuit.
FIG. 18 is a circuit diagram of the bridge circuit.
FIGS. 19, 19A-19J present a flow chart illustrating the microprocessor controlled operation of the window covering shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a window covering assembly 100 of the present invention. The assembly comprises a head rail 102, a bottom rail 104, and a shade 106. Preferably, the head rail 102 and bottom rail are formed from aluminum, plastic, or some other light weight materials. The shade 106 shown FIG. 1 is an expandable and contractible covering preferably made from a light fabric, paper, or the like. The shade of FIG. 1 is shown to be a cellular honeycomb shade; however, a pleated shade, horizontal slats, and other liftable coverings can also be used.
As seen in FIGS. 1 and 2, the head rail 102 comprises a bottom panel 108, a back panel 110, end caps 112 and a front panel 114. The front panel 114 is hinged by pins, attached at its upper end corners, to the end caps 112. This facilitates access to the cavity 116 within the head rail 102 behind the front panel's front surface 118. Alternatively, the front panel 114 can be hinged to the bottom member 108, or even be fully removable and snapped on to the rest of the head rail.
A plurality of lift cords 120 descend from within the head rail 102, pass through the cells of the honeycomb shade 106, to the bottom rail where they are secured by known means. The weight of the bottom rail 104 and shade 106 are supported by the lift cords 120, causing the latter to normally undergo tension.
FIG. 3 shows a top view of the cavity 116. Within the cavity 116 are an elongated tube 150 forming a battery pack which houses batteries 152 and is mounted on the cavity-facing side of the front panel 118. The tube 150 is preferably formed from a non-conductive material such as plastic. Also mounted in the cavity is a motor 122 operatively engaged to a rotatably mounted reel shaft 124, around which reel shaft the lift cords 120 are wound and unwound. Preferably, the reel shaft is hollow to reduce its weight. This reduces the torque and power requirements, thus extending battery life. A printed circuit (PC-) board 126 which carries much of the electronic circuitry of the assembly is also housed in the cavity.
As best seen in FIGS. 3 and 4, an interface module 128 communicates between the front surface 118 and the cavity 116. The interface module 128 comprises an infrared (IR) receiver and a manual switch 130. On the front surface 118, the manual switch 130 and a daylight-blocking window 132 are visible. The manual switch 130 can be activated by a user at any time. The window 132 covers the photoreceiver (i.e., transducer) of the IR receiver and helps extend the life of the batteries by preventing daylight from needlessly activating the transducer. One skilled in the art would recognize that an IR receiver, whose transducer has a built-in daylight-blocking window or a daylight-blocking coating, may also be used. The important thing is that the transducer not respond to daylight, and preferably be arranged such that it only responds to infrared light. It should be noted that the shade has no manually operated pull cord. Thus, the manual switch 130 on the front panel, and the IR receiver are normally the only means for operating the window covering.
As shown in FIG. 6, the motor 122 and its transmission 134 are operatively connected to a drive rod 136 having a square cross-section. The drive rod 136 is received by a telescoping reel shaft 124 which turns in spaced-apart bearings 138, each integrally formed with a reel support 140. When the drive rod 136 turns, the reel shaft 124 turns and also telescopes in an axial direction, one rotation of the reel shaft corresponding to an axial movement approximately equal to the thickness of the lift cord 120'. Thus, the lift cord passes through the bottom plate of the head rail at substantially the same position as it winds and unwinds. Thus, as seen in FIG. 6, the lift cord 120' is wrapped around the reel shaft 124, each turn abutting its neighbor without overlap, and its end 142 secured to the reel shaft by a ring-shaped clamp 144.
FIG. 7 illustrates the significance of having a particular lift cord 120' pass through the bottom panel 108 at the same position, as it winds and unwinds. A lift cord detector 146, formed as a reed switch, is mounted on the inside surface of the bottom panel 108. The lift cord detector 146 is positioned such that the lift cord 120' abuts the detector's reed 148, when there is tension in the lift cord 120'. When it abuts the reed 148, the lift cord 120' closes a connection in the switch. In the present design, the detector's reed 148 must be in abutment with the cord 120' for the motor 122 to lower the shade.
There are two situations of interest in which the detector's reed 148 no longer abuts the lift cord 120' during descent, causing the motor to stop. The first is when the tension in the lift cord 120' is relaxed. This happens, for example, when the bottom rail 104 meets with an obstruction, such a person's hand or an object on a window sill. In this first situation, the function of the lift cord detector 146 is to monitor the tension in the cord 120'.
The second situation is when the descending shade fully unwinds the lift cord 120'. In this latter case, as the reel shaft 124 makes its final rotation, it comes to a stop after bringing the end 142 of the lift cord 120' past the reed 148 and thus, no longer in abutment therewith. In such case, the lift cord 120' hangs from the reel shaft 124 in a position that is laterally displaced from the position it occupied when it was wrapped around the reel shaft 124. In this second situation, the function of the cord detector 146 is to gauge the lateral position of the lift cord 120' as it hangs from the reel 124.
It should be noted that the function of gauging the lateral position of the lift cord may be performed a number of equivalent means. For instance, if the lift cord is thick enough, an optical sensor comprising an LED and a photodetector may suffice. The lift cord 120' would then obstruct the light path in a first lateral position, and would not obstruct the light path in a second lateral position. And if the lift cord 120' is formed from a metallic material, it may also be possible to arrange a magnetic sensor to detect a lateral movement of the lift cord 120'. Such sensors, however, would require power to operate, and would not be able to simultaneously detect tension; therefore, they are not preferred.
As shown in FIG. 8, the power supply for the assembly of the present invention is a battery pack 150 comprising eight 1.5V AA batteries 152. The batteries, which preferably are non-rechargeable, are laid end-to-end, in electrical series with one another, thus providing 12 volts. The batteries are housed in a single elongated tube 150 which is mounted via brackets 154 fixed to the back side 156 of the head rail's front panel 114. With the batteries 152 laid end-to-end and substantially parallel to the reel shaft 124, substantially space savings is realized. This allows the motor, rotatable reel shaft, battery-based power supply, and electronics to be held within a housing having a cross-section less than 13/4" by 13/4".
A coil spring 158 mounted on the back side 156 biases a first end of the elongated tube 150, forcing a positive battery terminal against a positive electrical contact positioned at the opposite, second end. A conductor strip 160 formed on an outer surface of the tube 150 connects the negative terminal of the battery pack 150 to a ring-shaped negative electrical contact 162. Leads from each contact ultimately provide an electrical connection from the battery pack 150 to the PC board 126, motor 122 and module 128.
As depicted in FIG. 9, the motor 122 and its associated transmission 134 are assembled as a drive unit 164, along with a protective drive plate 166. The drive plate 166 is formed with an annular boss 168 through which the drive coupling 170 protrudes. A pair of diametrically opposed pins 172 secure the drive plate 166, transmission 134 and motor 122 to each other. This facilitates assembly of the hardware within the head rail.
The drive unit 164 is mounted in an elongated aperture 174 formed in a bulkhead 176. The bulkhead itself is rigidly fixed to the floor of head rail, on the inside surface of the latter's bottom panel 108. Clips 178 formed on a bulkhead top panel 180 help retain the drive unit 164.
As the bulkhead 176 is rigidly fixed to the head rail, any eccentricity in the motor 122 and drive unit 164 is transferred, in the form of vibrations, to the entire head rail 102. This vibration is amplified by the head rail, causing the latter to emit annoying noises. To reduce vibrations imparted to the bulkhead 176 by the drive unit 164, a resilient vibration dampening bushing 182 is used to mate the drive unit to the bulkhead. The bushing 182, which preferably is formed from neoprene rubber having a Shore A hardness of between 60-70, has a substantially cylindrical base member 184. The base member 184 is provided with a central aperture 186 shaped and sized to receive the annular boss 168 formed on the drive plate 166, and is further provided with a pair of apertures 188 adapted and positioned to receive the pins 172. On one side of its cylindrical base 184, the bushing 178 is provided with an elongated boss 190 integrally formed therewith. The elongated boss is shaped and sized to be received by the elongated aperture 174 in the bulkhead. In this manner, the bushing 182 both supports the drive unit 164 within the head rail, and also provides vibration dampening to reduce motor noise during operation of the window covering 30.
As shown in FIG. 12, one end of the drive rod 136 is integrally formed with a flange 192. Preferably they are formed from a hard plastic, or the like. The flange 192 is rotatably mounted between a pair of upstanding ribs 194 supported on the inside surface of the head rail's bottom panel. The ribs prevent the drive rod 136 from moving in an axial direction as it is turned. One end of drive shaft 196 is connected to the drive rod 136 at the flange 192. The opposite end of the drive shaft 196 is adapted to engage the transmission coupling 170 at a point between the bulkhead 176 and the flange 192. Thus, coupling 170, drive shaft 196, flange 192 and drive rod 136 all turn together when the motor is operated.
Mounted on the drive shaft 196 is a star wheel 198, which has four equidistantly spaced, radial spokes 200. The star wheel 198 turns with the drive shaft 196 and the spokes interrupt a path between two objects, represented by 206a, 206b. As the star wheel turns, the number of such interruptions is counted by a rotation counter. This number can then be translated into the number of revolutions of the reel shaft 124 relative to some starting point. The value in the rotation counter may then be used to compare with an upper or a lower limit count value saved in a memory register.
Either magnetic or optical sensing may be used in conjunction with the spokes 200. For magnetic sensing, a permanent magnet 202 is attached, by adhesive or equivalent means, to the radially outward end of each spoke 200. A magnetic sensor 204 comprising a pair of spaced apart sensor bars 206a, 206b is mounted on the underside of the PC-board 126. As the star wheel 198 turns with the drive shaft, its magnet-tipped spokes 200 pass between the sensor bars. The number of resulting magnetic disturbances is then counted, and this number is used in the position determination.
Alternatively, instead of a magnetic sensor, an optical sensor may be used. In such case, a light emitting diode (LED) 206a, arranged to emit light having a narrow wavelength, is positioned on one side of the star wheel 198. A phototransistor 206b responsive to that wavelength is positioned on the other. The LED and phototransistor are used to count interruptions by the spokes, as disclosed in U.S. Pat. No. 4,856,574 to Minami, whose contents are incorporated by reference in their entirety.
In the present invention, to extend battery life, the magnetic sensor, or, alternatively, the LED and phototransistor, are powered and monitored only when the motor is running. More specifically, they are powered just an instant before the motor is activated, and they are turned off just after the motor stops running.
FIG. 13 presents a block diagram of the circuit 210 used to control the shade 106. The battery pack 150 supplies all power to the circuit 210 via a power supply 212. Power supply 212 provides battery protection, noise filtering and voltage regulation. It also outputs a 12 volt supply to power the motor, and a 5 volt supply to power the rest of the circuit.
The heart of the circuit is a microprocessor 214, part no. 16C54. This processor is advantageous in that any port pin can be used for input or output. Also, an output port can put out a 5 volt signal capable of driving 25 mA of current. Thus, the processor itself acts as a low-current power supply of sorts. The processor is provided with a central processing unit, a non-volatile read-only memory (ROM), and a random access read-write memory (RAM). The ROM stores executable program code which is automatically entered upon booting the circuit by connecting the batteries. Alternatively, if a POWER ON switch is provided, this code is entered when such a switch is activated. The RAM includes a number of memory locations used for maintaining position data, status data, signal flags and the like. To extend battery life when there is no activity, the processor is cycled between a quiescent state and a sleep state. A built-in watchdog timer wakes up the processor from the sleep state. In the quiescent state, the processor 214 check a manual switch 130 and an IR receiver 216 to see if there are any inputs to which it should respond. If there are, the processor then enters an active state to process the input and take any other necessary action in response thereto. Upon conclusion of the active state, the processor is returned to the sleep state, after which the quiescent/sleep cycle is resumed.
The processor 214 is connected to the interface module 128. A 5 volt power line, IRSIG, and a ground connection are supplied by the processor to the interface module 128. Two signal lines, one from the manual switch 130, MAN, and another from the IR receiver 216, IRSIG, are returned to the processor.
The manual switch 130 can be either a contact switch, which activates a motor only when it is being depressed. Alternatively, switch 130 can be a single throw switch, which is activated once to start the motor, and activated a second time to stop the motor, unless, the motor stops by itself for some other reason. Either type of switch can be used, so long as the microprocessor 214 is appropriately programmed. Regardless of which type of switch is used, the switch output is presented on line MAN and this is read by the processor 214.
In the preferred embodiment, an IR transmitter 218 having separate UP 220a and DOWN 220b buttons is used to remotely activate the shade. The IR transmitter is also provided with a two-position channel selection switch 222, which allows a user to choose between two channels, A and B. The channel selection feature is especially advantageous in rooms where more than one window covering assembly is to be installed.
When either the UP or the DOWN button is pushed, a coded sequence of pulses corresponding to the button pushed and the channel selected, is generated. This sequence comprises a command signal. Each sequence has an identical number of pulses, and the sequence is repeated as long as the button is depressed. Each pulse in a sequence has a predetermined width of between 0.8 and 2.8 msec and is modulated with a 38 kHz carrier before being transmitted.
In the preferred embodiment, the IR receiver is a TFMS 5..0, available from TEMIC Telefunken. It filters and demodulates the sensed command signal and outputs a sequence of pulses corresponding to that generated within the transmitter 218 before being modulated. These pulses are output on line IRSIG and are read by the processor 214 by sampling to determine the length of each pulse. After reading the incoming sequence, the processor 214 matches it against a reference sequence stored in ROM. If a match occurs, the processor then sends out the appropriate signals to energize the motor, if other conditions are met.
To extend the life of the battery, the IR receiver 216 is cycled on and off by the processor 214 in one of two power cycle modes, a first, "look" mode, and a second, "active" mode. With no sensor activity and the motor off, the receiver 216 is normally in the look mode. In the look mode, power to the receiver 216 is alternatingly turned off for about 300 msecs, and then turned back on for about 7.1 msec. This means that, on average, a user must depress a transmitter button for about 1/3 second before any response can be expected. During the 7.1 msecs in which the receiver is powered, the processor checks the receiver output every 33 μsecs to see if a valid pulse, i.e., one between 0.8 and 2.8 msecs, has been received. Whether or not one has been received, the receiver 216 is turned off.
If no valid pulse has been received, the receiver is allowed to remain in the look mode. If, however, the microprocessor determines that a valid pulse was received, it then shifts the receiver into the active mode. In this mode, the receiver remains off for 9.5 msecs, and then is turned on for about 46 msecs, and a new alternating cycle of 9.5 msecs off and 46 msecs on, is established. When it is in the active mode, the receiver's output is checked by the processor every 160 μsecs. In the active mode, valid pulses, and even valid sequences of pulses (i.e., those sequences capable of activating the motor), may be received and interpreted by the processor 214.
If neither a valid pulse, nor a valid sequence is received in that first 46 msec period of the active mode, the processor shifts the receiver back to the look mode beginning with the next off cycle. If, instead, a valid sequence is received, the processor 214 and associated circuitry turn on the motor 122, and the receiver is allowed to remain in the active mode as long as the motor is running. Thus, with the motor running, the receiver is cycled off for 9.5 msecs and on for 46 msecs. Once the motor stops, whether due to a transmitted signal, or due the shade 106 reaching either an upper or a lower travel limit, or an obstruction, the receiver is shifted back into the look mode.
It should be noted that the above times are nominal values; actual times may vary by as much as 25%, depending on what other inputs the processor receives. It should also be noted that if the receiver output is continuously low for a predetermined number of cycles, e.g., 10 cycles, the receiver is considered to be in saturation. In such case, the processor shifts the receiver to the active mode to clear this situation.
In summary, then, the receiver 216 is switched between one of two power cycle modes. Both transmitted signals and motor status determine when the receiver is switched between the two modes. In a given mode, the length of time for which the receiver is turned on in each power-on, power-off cycle, is substantially the same. Also, the length of time for which power is continuously connected to the IR receiver 216 is independent of the content of the data received during that connection period. Thus, even if a valid pulse is received during a power-on period, power to receiver will be disconnected at the end of that period. This differs from the aforementioned U.S. Pat. No. 5,134,347 to Koleda, whose contents are incorporated by reference in their entirety, wherein power to the receiver is continued if a valid signal is received in the look mode.
To activate the motor 122, four control lines 224 are connected between the processor 214 and a bridge circuit 226. Two of the four control lines are connected to base terminals of a pair of NPN bipolar junction transistors (BJTs), each of which serves as a switch to control one half of the bridge circuit 226. The remaining two control lines are connected to the gate terminals of a pair of low power field effect transistors (MOSFETs). Each of the MOSFETs forms the lower portion of one half of the bridge circuit 226, allowing current to flow through its corresponding half when that FET's gate is activated by the processor 214.
The circuit 210 includes a sensor subcircuit 228 which gathers status information from one of three different sensors. The microprocessor powers the sensor subcircuit 228 at predetermined times through line IPWR, which is connected to resistor R3, and reads the sensor output through line INP. To read a particular sensor, it must first be enabled through a dedicated line DRV -- CS, DRV -- LL and OPT -- LED from the processor 214.
One of the three sensors is a channel select strap 230. The channel select strap 230 allows a user to enable the processor 214 to match a received command signal only with stored sequences corresponding to the selected channel. Preferably, the channel select strap 230 can be accessed either from outside the head rail or by simply opening its hinged front panel 114. The channel select strap can be formed as a simple wire or a jumper connector connecting two pins or leads. Alternatively, it can be formed as a two-position switch, much like the channel selector 222 on the transmitter 218. When the wire or jumper connector is intact, the processor 214 will try to match received command signals with stored sequences corresponding to channel A. And when the wire or jumper connector is not in place, e.g, when the wire is cut or the jumper connector is removed, the processor tries to match received command signals with stored sequences corresponding to channel B.
To determine which channel has been selected, the processor 214 powers the sensor subcircuit 228 using line IPWR, enables the channel select strap using line DRV -- CS, and reads the input on line INP. In normal use, the channel selector strap 230 is only examined (i.e., IPWR and DRV -- CS are both activated and INP is monitored) upon power start-up. As stated above, power start-up takes place when the batteries are first connected or when the power switch is activated, if a power switch is provided. Thereafter, if the channel select strap 230 is altered to designate a different channel, the processor 214 will continue to match received sequences only against stored sequences corresponding to the previous channel. Thus, after changing the channel select strap, the power must first be turned off before the processor 214 will recognize sequences corresponding to the newly directed channel.
One skilled in the art will recognize that the channel select strap 230 may be configured to allow one to select from among more than two channels. This can be done, for instance, by using a plurality of jumper connectors or a dip switch, or other device, which allows only one channel to be designated at a time. In such case, the processor 214 must connect an enable line, similar to DRV -- CS, to each of these channel selection connectors and selectively activate them upon start-up. Alternatively, the processor 214 may output a set of coded enable lines which are then connected to a multiplexer, and from there to each of the channel selection connectors. If a plurality of channels are provided, the processor 214 must also store UP and DOWN sequences for each of these channels, and these sequences must include enough pulses to uniquely code for the chosen number of channels. Finally, the transmitter 218 should be provided with a multi-position switch or dial, allowing it to select from among the various channels and output corresponding UP and DOWN sequences. Such a configuration can allow a single transmitter to selectively control a plurality of shades.
The second sensor monitored by the processor 214 is the lift cord detector 146, discussed above. To determine whether the lift cord 120' is abutting the lift cord detector 146, the processor 214 powers the sensor subcircuit 228 using line IPWR, enables the lift cord detector 146 using line DRV -- LL, and reads the input on line INP. It should be noted that current to the motor does not flow through the lift cord detector 146; only a current and voltage sufficient to be detected by the processor 214 is necessary.
The third sensor monitored by the processor 214 is used to count the number of interruptions made by the star wheel 198, and thus indirectly count the number of revolutions that the drive shaft 196 turns. As represented by the dashed line 234 from the motor 122 to the sensor 232, motor rotation is indirectly coupled to the sensor 232 in this manner. In the preferred embodiment, the third sensor 232 is an electro-optic sensor 232, although a magnetic sensor may also be used, as explained above. The electro-optic sensor creates a light path which is interrupted by the star wheel 198. The sensor 232 comprises a light emitting diode LED1 and a phototransistor PT1. As the motor 122 turns, so does the star wheel 198, and the interruptions of the star wheel affect the output of the phototransistor PT1.
As explained above, the electro-optic sensor 232 operates only when the motor is just about to run and continues to operate so long as the motor is running. Thus, to activate the electro-optic sensor 232, the processor powers the sensor subcircuit using line IPWR, enables the light emitting diode LED1 using line OPT -- LED and reads the input on line INP. Each time the star wheel 198 interrupts the path between LED1 and PT1, this interruption is sensed by the processor on line INP.
Thus, when the motor is just about to run, and also while the motor is running, the processor 214 powers the sensor subcircuit 228. It then periodically enables the cord detector 146 with line DRV -- LL and reads the input on line INP, and also periodically enables LED1 and reads the input on INP.
In this manner, the microprocessor monitors these sensors with a single sensor input line. After power startup, only the lift cord detector 146 and the optical sensor 232 are monitored. And even these two are monitored only if the processor has been directed to turn on the motor 122 asked to turn on by either the transmitter 218 or by the manual switch 130.
FIG. 14 presents a circuit diagram of the power supply. Power is supplied by the battery pack 150. Diode D3 provides battery reversal protection. The power supply provides a 12 volt source to drive the motor and a 5 volt source to drive the remainder of the circuit. A voltage regulator U2, which has a quiescent current of about 1 μA, is always on, providing a 5 volt source. Capacitors C1 and C2 and resistor R1 filter motor noise connected to the 12 volt supply. This prevents the motor noise from affecting the voltage regulator U2. Capacitor C3 provides added power filtering. The values of the resistors and capacitors for the entire circuit are presented in Table 1.
FIG. 15 shows input and output lines connected to the processor 214. Resistor R2 and capacitor C5 from an oscillator at nominally 2.05 MHz (plus or minus 25%). This provides an internal timing clock for the processor.
FIG. 16 presents the circuitry of the interface module 128. A 4-pin connector J3 on the interface module 128 communicates with a 4-pin connector J3 on the PC-board. As explained above, the four lines include an IR receiver power line IRPWR, an IR receiver signal line IRSIG, which is active low, a ground connection shared by both the manual switch 130 and the IR receiver 216 IRSIG, and the manual switch output line MAN which is pulled high by pull-up resistor R5, and is also active low.
TABLE 1______________________________________Component ValuesCOMPONENT VALUE______________________________________C1 10 mFC2 10 mFC3 10 mFC5 22 pFC6 0.1 μFR1 51 kΩR2 10 kΩR3 100 kΩR4 300 kΩR5 100 kΩR6 1 kΩR7 1 kΩR8 1 kΩR9 620 Ω______________________________________
FIG. 17 shows a circuit diagram of the sensor subcircuit 228. To enable any of the sensors, the processor 214 must apply power to the circuit by driving IPWR high (i.e., 5 volts) and monitor line INP. The processor must also enable the sensor it wishes to monitor by driving one of normally high OPT-LED, DRV -- LL and DRV -- CS lines low (i.e., setting it to 0 volts).
To determine the state of the channel selector strap 230 upon power startup, the processor 214 drives IPWR high, drives DRV -- CS low (i.e., sets it to 0 volts) and monitors INP. If INP is low, the channel selector switch is deemed to be intact, and so the processor is informed that it should match incoming signals against reference sequences for channel A. If, on the other hand, INP is high, there is no continuity across the channel select strap 230, and the processor knows to match for channel B.
To determine the state of the lift cord detector 146, the processor again drives IPWR high, drives DRV -- LL low, and monitors INP. If INP is low, this indicates that the detector's reed 148 is closed and so the lift cord 120' must be abutting the reed 148. This will inform the processor that there is tension in the lift cord 120' and that the shade is not at the bottom.
Finally, to activate the optical sensor 232, the processor 214 drives IPWR high, OPT-LED low, and monitors INP. This allows current to flow through LED1, causing it to emit light. This light is sensed by the phototransistor PT1, causing it to conduct and voltage to drop across resistor R3. Thus, when PT1 conducts, line INP is low. Each time the star wheel 198 interrupts the path between LED1 and PT1, line INP temporarily goes high. The number of times this line transitions from low to high and back to low is counted by the processor 214, and this number is translated into the number of rotations of the reel shaft 124 relative to some starting point.
When the motor is energized, the optical sensor 232 and star wheel 198 serve a second purpose. Each time the motor 122 is activated, the processor 214 starts an internal stall timer, which is formed as a register in memory. The stall timer times the interruptions of the magnetic or optical path, as caused by the spokes 200 of the star wheel 198. Each time an interruption occurs, the stall timer is reset. If the stall timer times out, it means that successive interruptions did not take place as quickly as they should have, and so the drive shaft 196 (and hence, the motor 122) did not turn as they should. This indicates a motor stall condition, such as when the shade is fully closed and can go no higher. Thus, whenever the motor 122 is running, the processor 214 checks for motor stall. If a stall is detected by the processor 214, it then no longer activates the motor 122, thus preventing damage to electrical and mechanical components of the assembly 100.
FIG. 18 presents the circuit diagram of the H-bridge circuit 226. Four lines from the processor control the bridge. Lines HLP and HRP control the H-bridge's left and right P-circuit, respectively, and lines HLN and HRN control the H-bridge's left and right N-circuit, respectively. As shown in FIG. 17, the P-circuit controls the upper half of the H-bridge, and the N-circuit controls the lower half of the H-bridge.
As shown in FIG. 18, lines HLP and HRP are connected to the base leads of left and right NPN switching transistors Q1 and Q3, through an associated current limiting resistor R6 or R8. When either line HLP or line HRP is driven high by the processor 214, the corresponding base-emitter junction on Q1 or Q3 is forward biased, allowing current to flow through that transistor, assuming other conditions are met. The collectors of Q1 and Q3 are connected via resistors R7 and R9 to the base leads of associated respective left Q2 and right Q4 PNP power transistors. The emitters of these two power transistors, Q2 and Q4, are connected to the 12 volt power supply, while their collectors are connected to separate leads of a connector J5. Connector J5, in turn, is connected to corresponding leads of the motor 122, allowing the latter to be energized in either direction.
Lines HLN and HRN are connected to the gates of N-channel MOSFETs Q5 and Q6, respectively. These lines are normally high when the motor 122 is not activated, thus turning on the Q5, Q6. This is the brake condition, which blocks current from passing from the collectors of Q3 and Q4, through the MOSFETs and on to ground.
When the motor 122 is to be activated in a first direction, HLP is driven high and HLN is driven low simultaneously. And, when the motor is to be activated in a second direction, HRP is driven high and HRN is driven low. In this manner, the bridge circuitry is configured to activate the motor in either direction. While the motor 122 is running, diodes D2 and D3 provide protection from back electro-motive force (EMF) from the motor 122 and capacitor C6 filters some of the high frequency noise from the motor 122.
The operation of the window covering assembly 100 is described next. As discussed above, the processor's RAM comprises a number of storage locations which keep track of sensor and status data. Among these storage locations are: a) a rotation counter, b) an upper limit register, which keeps track of the upper limit to which the shade may rise, c) a looking-for-upper-limit flag, which keeps track of whether or not the processor should look for an upper limit, d) a channel register, which keeps track of which channel's reference sequences should be used for matching with the received sequences, and e) a direction register, which keeps track of the last direction of shade travel.
On power startup, the rotation counter and upper limit counter are both set to a large, predetermined value, indicating that there is no upper limit, and the looking-for-upper-limit flag is set to not look for an upper limit. Also, the last direction counter is set to up (so that if the manual switch 130 is pushed, the shade will go down), and the channel register is set to A or B, depending on the channel strap.
After these registers are initialized, the processor enters a quiescent state in which the processor 214 first checks whether the manual switch 130 has been pushed. If the manual switch 130 has not been pushed, the processor next turns on the IR receiver 216 for 7.1 msec and then turns it off. If no valid pulse was received within that period, the processor enters a sleep state for a predetermined period of time, about 300 msecs. As it enters the sleep state, the processor 214 makes sure that the transistors Q2 and Q4 are off, MOSFETs Q5 and Q6 are on (brake) and that all other outputs and sensors are off. After waking up, the processor 214 loops through the quiescent state once again. If, during the quiescent state, either the manual switch 130 is pushed or a valid pulse is received, the processor 214 enters the active state.
In the active state, the processor 216 processes the input, and takes any necessary action in response, such as activating the motor 122. When the motor is running, the IR receiver is 216 is placed in the active mode and the processor 216 checks IRSIG, checks the lift cord detector 146, updates the rotation counter with each interruption, and checks the stall timer, and the manual switch 130.
At any given time, the shade 106 can be in one of three positions: 1) shade fully up (open), 2) shade fully down (closed), and 3) the shade partially down. Also, as stated above, the shade can be activated by either a) the manual switch 130, or b) either button 220a, 220b on the transmitter 218. This gives a total of six combinations, or examples, to illustrate processor behavior, when in the active state.
EXAMPLE 1
Shade 106 fully up (open) and the manual switch 130 pushed. In this case, the lift cord detector 146 is abutted by the cord 120', and so is closed. The processor 214 first checks the direction register and determines in which direction the shade 106 last travelled.
Case 1a. Last direction of travel was "up". The appropriate half of the bridge circuit is turned on, and, after an appropriate delay to avoid a short circuit, the other half of the bridge circuit is turned off. The motor is turned on and the shade goes down. The shade will continue to travel downward until a) the lift cord detector 146 is opened by rotating the cord 120' off the reed 148 when the shade reaches the bottom of its travel, b) the shade encounters an obstacle, relieving tension in the cord 120' and causing it to no longer abut the reed 148, c) the manual switch 120 is pushed a second time, or d) either transmitter button 220a, 220b is pushed. Regardless of which of these events take place, the direction register is toggled to indicate that the last direction was "down", and motor and shade are stopped, after which the processor enters the sleep state.
Case 1b. Last direction of travel was "down". The processor will first check to see whether the shade is at the upper limit (i.e., the value in the rotation counter matches that in the upper limit register). If this is the case, the processor will ignore the manual switch and enter the sleep state. If, for whatever reason, the rotation counter indicates that upper limit has not been reached, the processor 214 will activate the motor 122 to try to force the shade up. As the shade will not go up, the stall timer will immediately time out, causing the processor to deactivate the motor. Following this, the direction register is toggled to indicate that the last direction was "up", and the processor enters the sleep state.
EXAMPLE 2
Shade 106 fully up (closed) and a transmitter 218 button is pushed. Again, the lift cord detector 146 will be closed. The processor 214 ignores the direction register and determines which button was pushed.
Case 2a. Down button 220b is pushed. The shade will go down. The processor and shade will behave in the same way as in Case 1a, except that the shade will stop if either transmitter button 220a, 220b is pushed a second time.
Case 2b. Up button 220a is pushed. The processor and shade will behave in the same way as in Case 1b. Again, the stall timer will time out, causing the motor to stop, after which the processor will toggle the direction register, and then enter the sleep state.
EXAMPLE 3
Shade 106 fully down (closed) and the manual switch 130 pushed. In this case, the lift cord detector 146 will be open, indicating that either the shade is fully lowered, or that the shade is resting on an object. The processor 214 first checks the direction register and determines in which direction the shade 106 last travelled.
Case 3a. Last direction of travel was "up". The processor 214 will determine that the lift cord detector is open. Because it is open, the processor will not allow the shade to be lowered, and so will enter the sleep state.
Case 3b. Last direction of travel was "down". The processor will determine that the lift cord detector is open. This will cause it to reset the rotation counter to zero, and enable the looking-for-upper-limit flag so that, upon ascent, the processor will compare the value in the rotation counter to the value in the upper limit register. The processor will then activate the motor to raise the shade. The shade will continue to travel upward until a) the stall timer times out, indicating that the motor has stalled (e.g., the shade is fully raised), b) the rotation counter reaches the value in the upper limit register, c) the manual button is pushed a second time, or d) either transmitter button 220a, 220b is pushed. Regardless of which of these events take place, the direction register is toggled to indicate that the last direction was "up", and motor and shade are stopped, after which the processor enters the sleep state.
EXAMPLE 4
Shade 106 fully down (closed) and a transmitter 218 button is pushed. Again, the lift cord detector 146 will be open, indicating that either the shade is fully lowered, or that the shade is resting on an object. The processor 214 ignores the direction register and determines which button was pushed.
Case 4a. Down button 220b is pushed. The processor 214 will determine that the lift cord detector is open and so it will not activate the motor to lower the shade. If the button 220b is pushed for less than 3 seconds, nothing else happens and the processor enters the sleep state. If, however, the button 220b is pushed for 3 seconds or longer, the upper limit counter is set to a large, predetermined value, indicating that there is no upper limit. After this, the processor enters the sleep state.
Case 4b. Up button 220a is pushed. The processor and shade will behave in substantially the same way as in Case 3b, except that the shade will stop if either transmitter button 220a, 220b is pushed a second time. Additionally, however, if a stall is detected when the shade is being raised from the lower limit, a new upper limit will be set. For this, the upper limit register will be set to 5 pulses less than the rotation counter, which has been reset to zero just before the shade began to rise. The new upper limit value will help ensure that the next time the shade is raised, (after first having been lowered), the shade will stop at the new upper limit, instead of continuing on and encountering a stall condition.
EXAMPLE 5
Shade 106 partially open and the manual switch 130 pushed. In this case, the lift cord detector 146 is abutted by the cord 120', and so is closed. The processor 214 first checks the direction register and determines in which direction the shade 106 last travelled.
Case 5a. Last direction of travel was "up". The shade will go down until a) the lift cord detector 146 is opened by rotating the cord 120' off the reed 148 when the shade reaches the bottom of its travel, b) the shade encounters an obstacle, relieving tension in the cord 120' and causing it to no longer abut the reed 148, c) the manual switch 120 is pushed a second time, or d) either transmitter button 220a, 220b is pushed. Regardless of which of these events take place, the direction register is toggled to indicate that the last direction was "down", and motor and shade are stopped, after which the processor enters the sleep state. This is similar to Case 1a.
Case 5b. Last direction of travel was "down". The processor will first check to see whether the shade is at the upper limit (i.e., the value in the rotation counter matches that in the upper limit register). If this is the case, the processor will ignore the manual switch and enter the sleep state. If the upper limit has not been reached, the shade will go up until a) the stall timer times out, indicating that the motor has stalled (e.g., the shade is fully raised), b) the rotation counter reaches the value in the upper limit register, c) the manual button is pushed a second time, or d) either transmitter button 220a, 220b is pushed. Regardless of which of these events take place, the direction register is toggled to indicate that the last direction was "up", and motor and shade are stopped, after which the processor enters the sleep state.
EXAMPLE 6
Shade 106 partially open and a transmitter 218 button is pushed. Again, the lift cord detector 146 is abutted by the cord 120', and so is closed. The processor ignores the direction register and determines which button was pushed.
Case 6a. Down button 220b is pushed. The processor and shade will behave in the same way as in Case 5a, except that the shade will stop if either transmitter button 220a, 220b is pushed a second time.
Case 6b. Up button 220a is pushed. The processor and shade will behave in the same way as in Case 5b, except that the shade will stop if either transmitter button 220a, 220b is pushed a second time.
The processor 214 executes a series of software instructions to control the window covering assembly. FIGS. 19 and 19-A to 19-J present a flowchart which illustrates this software control. Processor operation begins with powering up the system in step 300. This is followed by step 302 in which various registers, counters and flags are initialized, and the channel strap is read. Once this initialization is finished, the processor enters the quiescent state in which the processor looks for activity from either the manual switch 130 or the IR receiver 216.
In step 304, the processor checks line MAN to see if the manual switch has been pushed. If so, control flows to step 314 in FIG. 19-A. If, however, the manual switch 130 has not been pushed, the IR receiver is turned on for 7.1 msecs and then turned off in the look mode (step 306). The processor then samples IRSIG to see whether a valid pulse was received (step 308). If so, control flows to step 316 in FIG. 19-B, If, however, no valid pulse was received, the processor enters a sleep mode (step 308) in which it remains, nominally, for 300 msecs before waking up (step 312). The processor then continues in the quiescent state with control looping back to step 304 to see if the manual switch 130 was pushed.
FIG. 19-A illustrates the control sequence when the manual switch was pushed when the processor was in the quiescent state. In step 314, the processor checks the direction register to see in which direction the shade last was asked to move. If the last direction was UP, it means that the shade should go down, and so control flows to step 332 in FIG. 19-D. If, on the other hand, the last direction was DOWN, the shade should now go up, and so control flows to step 324 in FIG. 19-C.
FIG. 19-B illustrates the control sequence when a valid pulse was received when the processor was in the quiescent state. First, in step 316, the processor places the IR receiver 216 in the active mode, discussed above. Next, in step 318, the processor attempts to match the received sequence of pulses with the reference sequences for the selected channel. If there is no match, the processor enters the sleep state (step 310). If there is a match, the processor determines which button on the transmitter, UP or DOWN, was pushed (step 320). If the UP button was pushed, control goes to step 324 in FIG. 19-C. If the DOWN button was pushed, the processor checks to see whether the lift cord detector reed is open (step 322). If the detector is not open, control goes to step 322 in FIG. 19-D; if it is open (indicating that the shade is either fully lowered or resting on an object), control goes to step 334 in FIG. 19-E.
FIG. 19-C illustrates the control sequence when the processor has been instructed by either the manual switch or the transmitter to raise the shade. The processor first determines whether the lift cord detector reed is open (i.e., whether the shade is fully lowered or is resting on an object) (step 324). If the detector is open, then the shade resets the rotation counter and sets the looking-for-upper-limit flag (step 326), and then turns on the motor to raise the shade (step 330). If the detector is closed, the processor first checks whether the shade is at the upper limit (step 328). If the shade is already at its upper limit, the shade need not be raised, and so the processor goes to sleep (step 310). On the other hand, if the shade is not already at its upper limit, it can rise some more, and so the processor turns on the motor to raise the shade (step 330). Whether or not the lift reed was open, control goes to step 344 in FIG. 19-F, after the motor starts.
FIG. 19-D illustrates the control sequence when the processor has been instructed by either the manual switch or the transmitter to lower the shade. The motor is simply turned on to lower the shade (step 332), after which control passes to step 344 in FIG. 19-F.
FIG. 19-E illustrates the control sequence when the lift cord detector reed is open and the down button on the transmitter has been pushed. The processor first starts a 3-second timer (step 334), which is used to determine whether the down button is pressed for the full three seconds. The IR receiver is maintained in the active mode (step 336) and the processor checks the IRSIG line to see whether the DOWN button is still being pressed (step 338). If the DOWN button stops being pressed at any time within those three seconds, the processor enters the sleep state (step 310), as the shade cannot be lowered (since the lift cord detector reed is open). The processor stays keeps checking the IRSIG line until either the DOWN button is released or until the 3 seconds are over (step 340), whichever occurs first. If the 3-second timer times out, the upper limit counter is reset (step 342), and the processor enters the sleep state (step 310).
FIG. 19-F illustrates the control sequence when the motor is running, either up or down. With the motor running, the IR receiver is in the active mode, the IRSIG and MAN lines from the interface module 128 are monitored, the optical sensor 232, and the lift detector reed 148 are polled, and the stall timer is operational (step 344). The processor then executes a loop to check on all of these.
When the IRSIG line is being monitored (step 346), control flows to step 358 in FIG. 19-G. When the processor polls the lift cord detector reed 148, it determines whether the reed is open (step 348). If so, control goes to step 362 in FIG. 19-H. When the processor polls the optical sensor (i.e, the phototransistor) it determines whether the light path has been interrupted (step 350). If so, control goes to step 366 in FIG. 19-I. If the stall timer times out (step 352), control goes to step 372 in FIG. 19-J. And when the MAN line is being monitored (step 354), the processor is interested in knowing whether the manual switch 130 has been pushed anew since the motor started running. If the manual switch has not been pushed anew, the motor continues to run and the processor continues to check the various inputs. If, however, it has been pushed anew, the motor is stopped (step 356) and the processor eventually enters the sleep state (step 310).
FIG. 19-G illustrates the control sequence when the motor is running and the IR receiver is being monitored. The processor checks to see if line IRSIG is active and if it is, whether either transmitter button has been pushed anew since the motor started running (step 358). If neither button has been pushed anew, the motor continues to run and the processor continues to check the various inputs. If, however, either button has been pushed anew, the motor is stopped (step 360) and the processor eventually enters the sleep state (step 310).
FIG. 19-H illustrates the control sequence when the motor is running and the lift cord detector reed is opened. The processor first checks to see whether the shade was going down when this happened (step 362). If it was going down, the motor is stopped (364), because the cord has fully unwound or because the shade bumped into an obstacle on the way down. After the motor is stopped, the processor enters the sleep state (step 310). If, on the other hand, the shade was going up, the processor doesn't care, and the motor continues to run and raise the shade.
FIG. 19-I illustrates the control sequence when the motor is running and an interruption in the light path is detected. Whenever the light path is interrupted, it means star wheel 198, and thus the reel 124 are turning, the shade is either being raised or lowered, and the motor is not stall condition. Thus, the processor resets the stall timer and increments the rotation counter (step 366). The processor then compares the rotation counter to the value in the upper limit register (step 368). If they do not match, it means that the upper limit for the shade has not been met, and the motor continues to run. If, on the other hand, they match, the upper limit has been reached. In such case, the motor is stopped (step 370), and the processor enters the sleep state (step 310).
FIG. 19-J illustrates the control sequence when the motor is running and the stall timer times out. When this happens, it means that the star wheel 198 and the reel 124 did not turn, even though the motor was on, thus indicating a motor stall condition. A motor stall can happen when the shade is all the way up and the rotation counter does not match the value in the upper limit register. It can also happen if the shade is held by an object which prevents the former from rising. Other situations may also cause the timer to time out. Regardless of what causes this, the motor is first stopped (step 372). The processor then checks whether the rotation counter was to stop when it reached the value in the upper limit register (step 374). If so, the upper limit register is set to a value slightly below the current rotation count (step 376). This will prevent stall due to a spurious upper limit register value, on a subsequent raising of the blind. After step 376 and also, in the event that the rotation counter was not to be matched against the upper limit register value, the processor enters the sleep state (step 310).
While the above invention has been described with reference to certain preferred embodiments, it should be kept in mind that the scope of the present invention is not limited to these. One skilled in the art may find variations of these preferred embodiments which, nevertheless, fall within the spirit of the present invention, whose scope is defined by the claims set forth below. | A wireless battery-operated window covering assembly is disclosed. The window covering has a head rail in which all the components are housed. These include a battery pack, an interface module including an IR receiver and a manual switch, a processor board including control circuitry, motor, drive gear, and a rotatably mounted reel on which lift cords wind and unwind a collapsible shade. The circuitry allows for dual-mode IR receiver operation and a multi-sensor polling scheme, both of which are configured to prolong battery life. Included among these sensors is a lift cord detector which gauges shade status to control the raising and lowering of the shade, and a rotation sensor which, in conjunction with internal registers and counters keeps track of travel limits and shade position. | 8 |
[0001] The current invention are CIP of co-inventor's co-pending filing or following projection light device including:
U.S. Ser. No. ______ Multiple function LED project Light has built-In Motor means, Filed on Sep. 5, 2013 U.S. Ser. No. ______ LED light has more than one reflective means to project Light or image, Filed on Sep. 10, 2013. U.S. Ser. No ______ LED light has kaleidoscope means, Filed on Sep. 10, 2013. U.S. Ser. No. 13/021,124 LED light has changeable image and pattern by kaleidoscope means to project to surfaces. Filed on Feb. 4, 2011 and public on Aug. 9, 2012, 2012-0200-828. U.S. Ser. No. 12/710,918 LED light has more than one reflector means, Now U.S. Pat. No. 8,8277,087 which similar with current invention to apply the kaleidoscope means which has more than one reflective means hereof use mirror or mirror-like means to assembly into kaleidoscope means. U.S. Ser. No. 11/806,284 LED light has more than one optic means, now U.S. Pat. No. 7,632,004 which has use more than one optics means which similar with current invention to apply the optics means in front of or back of back of kaleidoscope means to create, adjust, magnify, reduce, enlarge the said the said image, LEDs light beams, LED lights' image, shape which including the any combination from optics lens, optics mirror, laser hologram, laser grating film, optics assembly U.S. Pat. No. 7,455,444 LED light has more than one LED light source, the current invention use more than one LEDs for matrix arrangements with Circuit means, IC means, sensor means, switch means, brightness control means, color mix means, color selection means, color freeze means, motor means, gear means, turn-On and turn-Off means to make the certain number of LEDs turn-On with desired color, brightness, light brightness output, light functions, matrix combinations, motor means, rotating means, gear set means to pass though the said kaleidoscope means, optics means, laser mans, motor means, gear means, to has desired light patterns. U.S. Ser. No. 12/948,953, U.S. Ser. No. 12/938,564 U.S. Ser. No. 12/886,832, U.S. Ser. No. 12/876,507, U.S. Ser. No. 12/771,003, U.S. Ser. No. 12/624,621, U.S. Ser. No. 12/914,584, U.S. Ser. No. 12/318,471, U.S. Ser. No. 12/318,470, U.S. Ser. No. 12/834,435 and also is continuous filing for co-inventor's prior filing cases as below issued patents: U.S. Ser. No. 12/292,153 (now is U.S. Pat. No. 7,871,192), U.S. Ser. No. 12/232,505 (now is U.S. Pat. No. 7,832,917), U.S. Ser. No. 12/318,473 (now is U.S. Pat. No. 7,832,918). LED light has laser means U.S. Ser. No. 12/624,621 (Now is U.S. Pat. No. 8,303,150) LED project light for Seasonal items U.S. Ser. No. 12/771,003 (now is U.S. Pat. No. 8,408,736) Light device has More than one project means. U.S. Ser. No. 12/876,507 (now U.S. Pat. No. 8,083,377) Light device has projection function with focus adjustable and project means can change position U.S. Ser. No. 12/886,832 Digital data projection Light device, Sep. 8, 2010 filed U.S. Ser. No. 12/938,564 Laser projection light device, Nov. 4, 2010 filed U.S. Ser. No. 12/948,953 LED light has time projection. Nov. 13, 2010 filed. U.S. Ser No. 13/021,107 LED light has 3Dimensional projection, Feb. 4, 2011 filed.
[0020] Above listed Projection light device total has (9) projection light device are parent filing cases as CIP filing of the current invention.
BACKGROUND OF THE INVENTION
[0021] Further more the Co-invention also has co-pending filing for light device has interchangeable power source for Wall outlets AC power and Energy storage means (Direct current) including the all kind of combination selection from prong mean, extension cord, adaptor, transformer, Solar, wind power, Batteries, chemical power, biologic power all can be interchange or for any AC or battery power for Desk Top and Plug In type of current invention of project light device has build-in kaleidoscope means. The interchangeable co-filing cases as below:
U.S. Ser. No. 12/318,473, U.S. Ser. No. 12/940,255 (Now U.S. Pat. No. 8,231,246) #FF-1
[0024] So the current invention are CIP for variety of co-inventor's co-pending or co-patents as above listed including: ( 1 ) Project light device ( 2 ) More than 1 optics means ( 3 ) More than 1 LEDs ( 4 ) More than 1 reflective means ( 5 ) Interchangeable power source ( 6 ) Laser Means ( 7 ) Adjustable focus and position changeable ( 8 ) motor & Gear set for moving adjustable.
[0025] This application has subject matter in common with U.S. patent application Ser. Nos. 12/710,561; 12/711,456; 12/771,003; 12/624,621; 12/622,100; 12/318,471; 12/318,470; 12/318,473; 12/292,153; 12/232,505; 12/232,035; 12/149,963; 12/149,964; 12/073,095; 12/073,889; 12/007,076; 12/003,691; 12/003,809; 11/806,711; 11/806,285; 11/806,284; 11/566,322; 11/527,628; 11,527,629; 11/498,874; 12/545,992; 12/806,711; 12/806,285; 12/806,284; 12/566,322; 12/527,628; 12/527,629; 12/527,631; 12/502,661; 11/498,881; 11/255,981; 11/184,771; 11/152,063; 11/094,215; 11/092,742; 11/092,741; 11/094,156. 11/094,155. 10/954,189; 10/902,123, 10/883,719; 10/883,747; 10/341,519; 12/545,992; and 12/292,580.
[0026] In particular, the following applications show light devices that have at least some features in common with included or optional features of the LED light device of the present invention: Ser. No. 12/710,561 (“LED power failure Light”); Ser. No. 12/711,456 (“LED light device has special effects”); Ser. No. 12/771,003 (“LED light device has more than 1 reflective means for plurality of image”); Ser. No. 12/624,621 (“projection device or assembly for variety of LED light”); Ser. No. 12/622,000 (“Interchangeable Universal Kits for all LED light”); Ser. No. 12/318,471 (“LED night light with pinhole imaging”); Ser. No. 12/318,470 (“LED night light with Projection features”); Ser. No. 12/318,473 (“LED night light with laser or hologram element”); Ser. No. 12/292,153 (“LED night light with Projection or imaging features”); Ser. No. 12/232,505 (“LED night light with Projection features”); Ser. No. 12/149,963 (“Removable LED light device”); Ser. No. 12/149,964 (“Surface Mounted Device with LED light”); Ser. No. 12/073,095 (“LED Track light device”); Ser. No. 12/073,889 (“LED light with changeable position with Preferable power source”); Ser. No. 12/007,076 (“LED light with changeable geometric system”); Ser. No. 12/003,691 (“LED light with changeable geometric dimension features”); Ser. No. 12/003,809 (“LED light with changeable features”); Ser. No. 11/806,711 (“Multiple LED light with adjustable angle features”); Ser. No. 11/806,285 (“LED Night light with outlet device”); Ser. No. 11/806,284 (“LED Night light with more than 1 optics means”); Ser. No. 11/527,628 (“Multiple function Night light with air freshener”); Ser. No. 11/527,629 (“LED Night light with interchangeable display unit”); Ser. No. 11/498,874 (“Area illumination Night light”); Ser. No. 11/527,631 (“LED Time piece night light”); Ser. No. 12/545,992 (“LED time piece Night light”); Ser. No. 12/292,580 (“LED Time Piece Night light”); Ser. No. 11/498,881 (“Poly Night light”); Ser. No. 11/255,981 (“Multiple light source Night Light”); Ser. No. 11/184,771 (“Light Device with EL elements”); Ser. No. 11/152,063 (“Outlet adaptor with EL”); Ser. No. 11/094,215 (“LED night light with liquid medium”); Ser. No. 11/094,215 (“LED Night light with Liquid optics medium”); Ser. No. 11/092,741 (“Night light with fiber optics”); Ser. No. 10/883,747 (“Fiber Optic light kits for footwear”); Ser. No. 11/498,874 (“Area Illumination for LED night light”); Ser. No. 11/527,629 (“Time Piece with LED night light”); Ser. No. 11/527,628 (“Multiple Function Night light with Air Freshener”); Ser. No. 11/806,284 (“LED Night light with more than one optics mediums”); Ser. No. 11/806,285 (“LED Night Light with multiple function”); and Ser. No. 11/806,711 (“Multiple LEDs Light with adjustable angle function”).
[0027] The applications of the inventor in general all apply physics or optics theory to a night light supplied with power from an outlet, battery, solar, or other power source. The present invention uses the physics or optics theory to create a plurality of LED light images on a surface. More specifically, the current invention uses more than one reflective means to transform a single LED spot light into a plurality of images on a surface to be seen by viewer. The principles of the invention may be applied to night lights of various types, including night lights disclosed in the above-listed patents and patent applications of the inventor, which may be powered by a variety of power sources, such as an outlet, batteries, solar, wind, or chemical power sources.
[0028] Because of the persistence of vision effect, caused by the human eye response time of more than 1/24 (41367) to 1/16 (0.0625) seconds, when an object moves faster than the human eye response time, the last image will stay in the human eye and brain for an extended period of time. This theory can utilized to save power by causing an LED or LEDs to flash with a very short on-time of around 10 msec or less. This principle is similar to that of a motion picture in which, if an object in front of human eye is displayed in 16-24 pictures per second, people will think all pictures are continuous. Hence, the current invention uses a related circuit, control means, IC, and/or micro controller to cause an LED light device to blink at a rate that is much faster than 16-24 times (cycles) per second, with the LED or LEDs being turned on for 10% of each cycle and off for 90% of the cycle to save up to 90% of power consumption or increase battery life by nine times more than the full steady-ON condition. This is a significant power saving for all battery power source applications. It will be appreciated that new LEDs may be coming soon to enable the LEDs to have an even quicker response time of less than 10 msec, and possibly less than 5 msec or 2 msec, to provide even greater power saving. such adjustment of the duration of each cycle's turn-on and turn-off duration time will cause even more power saving to meet the green world concept. This is one of the very important concepts of the current invention.
[0029] Further cost saving can be achieved in the case of a battery powered unit by using a circuit with proper electric components, parts, and accessories to raise the voltage output of the batteries to trigger the LED or LEDs even though the number of batteries is less than that normally required to generate the required voltage. This can counter the tendency of people to use a large quantity of batteries and save substantial cost, which is another important advantage of the current invention.
[0030] A preferred embodiment of the current invention includes an LED night light with more than one reflective means within the geometric shape optics means that provide a plurality of LED light beams to passing through or reflecting within the more than one reflector means inside the optics means. The LED night light including at least one LED arranged on the inner of the partial transparency geometric optics means has more than one of the said reflective means, at least one second reflective means within the geometric optics means which can reflect an LED light beams from its surface to 1 st or others reflective means surface(s) back and forth so one LED light beams been reflected and travel within the optics means and partial of LED light beam are passing though the partial transparency optics means to outside.
[0031] In this embodiment, a plurality of the LED beam can be project outside though the said surface(s). Furthermore, at least one of the reflective means may be partially transparent so that the plurality of LED light beam is passing though from the said surface(s) thereof. The other Plurality of the light beam is been reflected or retro-reflected within the other reflector means and passing though some other surface(s).
[0032] The LED or LEDs of this embodiment are preferably connected with circuit means, power means, contact means, conductive means, switch means, sensor means, motor means, spin means, rotating means, gear set means, speed control means, printed circuit means, integrated circuit (I.C.) means and/or related parts and accessories to cause the LED or LEDs to turn on and off according to a predetermined time period, functions, colors, and/or effects to provide a desired lighting performance.
[0033] In the above-described preferred embodiment, the reflective means may be a mirror, chrome finished piece, polished piece, double-side mirror, or any surface having reflective and passing though both optics properties suitable to the current invention.
[0034] The partial transparent or see-though properties can be provided by a transparent piece, colored transparent piece, or any other piece that allows light beams to pass there through. A power source of this embodiment can be in the form of an outlet, batteries, solar power, chemical power, or wind power.
[0035] The LED or LEDs can be selected from any combination of single color, multiple color, multiple piece, standard, and special LED assemblies, LED number from 1 to N (N can be any number) to arrange in desire matrix spacing which available on the market.
[0036] Finally, the distance, position, orientation of the reflective means may be changed basing on the selected geometric shape of optics means. The LED or LEDs arrangement for different of LED number, position, color, IC chip, control means, circuit means, functions, and brightness can create a desire plurality of light patterns, show, color changing, images changing, moving effects to people to be seen on surrounding surface(s) including walls, ceiling, floor, or desire surface(s).
[0037] The said geometric optics means can has any shape with multiple construction and the said the geometric optics means has desire combination selected from the passing though lens, reflective lens, convex lens, concave lens, laser lens, hologram lens on the inner or outside surface or all side of the surface to make certain light effects.
[0038] According to another preferred embodiment of the invention, an LED light device having power saving features includes at least one LED or LEDs for a light source, at least one housing having space to install circuit means, conductive means, electric components parts and accessories, switch means, sensor means, an integrated circuit (IC), and/or a micro controller to connect with a conventional market-available power source to cause the LED or LEDs to turn on and turn to provide predetermined functions or effects, with a predetermined duty cycle, color, and/or brightness.
[0039] The power-saving features are obtained by using the control means to cause the LED or LEDs turn-on for only a certain percentage of each cycle. In particular, the turn on time is selected to meet the persistence of vision of the human eye, so as to take advantage of the human eye's response time of 1/24 to 1/16 second so that the blinking LED or LEDs looks as if it were continuously on.
[0040] According to yet another embodiment of the invention, an LED light device having cost saving features includes at least one LED or LEDs as a light source, at least one housing having space to install circuit means, conductive means, electric components parts and accessories, switch means, sensor means, an integrated circuit (IC), and/or a micro controller to connect with a conventional market-available power source, preferably batteries, to cause the LED or LEDs to turn on and turn off according to a predetermined function or effects, duty cycle, color, and/or brightness.
[0041] In this embodiment, cost saving is obtained by providing batteries having a total voltage that is less than the LED trigger voltage and by providing electric components and related parts and accessories to increase the voltage output of the batteries to greater than the LED trigger voltage.
[0042] As noted above, the current invention uses geometric shape optics-means has built-in more than one reflective means to create a plurality of LED light beam passing though, reflect, retro-reflect by the more than one of reflective means. The relative distance, position, and/or orientation of the more than one reflective means (and optional additional) reflective means will result in different light beam performance. This is a very low cost and simple way to make a splendid and eye catching light projection unit for people, with any desired power source such as a battery, USB power, outlet power, generator power, chemical power, solar power, wind power or other equivalent power source from the marketplace.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 and FIG. 1-1 and FIG. 1-2 : shows a first preferred embodiment of the current invention has prong means with more than one of geometric optics-means to cause a plurality of light emit out to project the images to be seen by a viewer. It also disclosure the interchangeable power source, USB wire or other power source for the current invention. a first preferred embodiment of the current invention has DC power-means or USB Power or ineterchageable power source
[0044] FIG. 2 and FIG. 2-1 and FIGS. 2-2 and 2 - 3 shows a first preferred embodiment of the current invention has AC power-means or other power source for DeskTop application of current invention with more than one of geometric optics-means to cause a plurality of light emit out to project the images to be seen by a viewer. Also teach the variety of added functions may fit within the spacing for the LED light because under the LEDs has plenty of space to add more added functions from electric device, digital device, communication device, computer device, consumer electric device categories.
[0045] FIG. 1-3 and FIG. 1-4 and FIG. 1-5 shows with preferred parts & accessories assembly for 1st Embodiment.
[0046] From FIG. 1-6 and FIG. 1-7 and FIG. 1-8 shows the 1st preferred embodiment's details parts name and comparison drawing for different viewing angle. Also, more details for the Big Light-Output area/opening/window which are much bigger than the LED light housing's cross section size.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] From FIG. 1 can see the LED light has more than one optics means to project light which has ( 1 ) Cam-means to change Rotating/spin to back and forth linear movement so make the 1st optics lens moving ( 2 ) Compact light device housing ( 3 ) Axis means to make 1 st optics lens to move fix direction ( 4 ) 1st optics means has wave texture to make light beam spread out to many direction to has the 1 st image project to the desired surface ( 5 ) Fix means to hold the electric parts & accessories including the substrate for the LEDs, 1 st optics lens, motor means, gear set means, circuit means, cam means, axis means, IC means, conductive means, wires, holder means, or other parts & accessories needed for the design ( 6 ) Axis means holder to hold the elongate axis which let install the 1 st optics means/lens to make the 1 st optics means/lens to move back-and-forth under predetermined directions so can make image moving effects while incorporate with motor means, gear set means, cam means and other parts & accessories for proper design the Rotating RPM with gear sets to meet requirement ( 7 ) Light-output area is much bigger cross-section size than compact housing so can project light wider to as big size as possible to cover majority of ceiling, walls, or any surfaces needed to be projected light beams ( 8 ) 2nd optics means fix on the top of light device as fix optics means has its texture to make fixed image. So work with the moving 1 st optics means's moving image with 2 nd optics means fix image so it can create the motion effects such as water wave, ocean wave, storm wave, . . . ( 9 ) Substrate means to install parts & accessories as above discussed ( 10 ) LEDs LEDs in any geometric matrix, installation for any spec.color, size, brightness, functions, pole, built-in IC, power or others LEDs as requirement.→These are parts of the preferred embodiment for the main construction to make LED light project light has more than one optics means for desired arrangement such as this embodiment has built-in motor means, gear set means, Cam means to make one optics leans moving back--&- forth to make moving light image and incorporate the 2 nd optics means to make steady/fix light image so can make the motion effects image to viewers.
[0048] From FIG. 1-1 can see 2nd Optics means has texture not moving fix on top and the 1st optics means has texture moved by motor+gear set+Cam means to make inner LEDs light beam image moving to hit the 2nd optics means light beam so make motion light beams project to areas.
[0049] From FIG. 1-2 can see the compact size of the light device its light output-area has much bigger size than the compact housing's s cross-section so can project maximum light beam to outside. The prong-means for outlet power source can design as interchangeble power source as inventor prior patents & Pending caseses. The current invention also can incorporate with the preferred other power source may in any combination from the USB power, AC adaptor, power, transformer, solar, chemical power or energy storage power also good for current invention.
[0050] From FIG. 1-3 and FIG. 1-4 can see. Circuit means to control motor, gear set, Cam means and LEDs for desire functions, effects, performance. Substrate means for oval shape so can fit into slide light output-areas. Motor means and gear-set means are connect with cam means to change the rotating/spin to the back-and-forth movement so can move the 1st optic means to right-n-left or front-n-back to make light image become moving image.
[0051] From FIG. 1-4 can see The preferred embodiment has oval shape substrate means can install circuit means, motor means, gear set means, cam means, electric parts & accessories so can to control the all electric functions as predetermined function and with added other electric items, digital data item for multiple value item.
[0052] From FIG. 1-5 : Can see how to install the substrate means and parts & accessories which may selected from group combination including motor means, gear set means, cam means, axis means, axis holder, 1st optics means, LEDs, Circuit means, conductive means, wire means, switch means, sensor means, remote means, prong means, USB wire means, USB plug & receptacle means, interchangeable power source means, AC power means, Transformer power means, adaptor means, solar power means, Wide light output area means, 2 nd optics means, 2 nd LED light arrangement, Night light, Power failure light, Remote control power source mans, USB charge means, AC outlets means and any other functions can add on the current inventions to add the value of products selected from electric functions, digital data function, power input & output functions, blue tooth functions, remote control function device(s) all fall inside the current claims. From the FIG. 1-5 can know The space arrangement for 1st preferred embodiment so it still have a lot of space can add other functions on current inventions may include: USB charger, AC outlets, blue tooth device, remote control device, power in-and-out device, Charger, power fail, removable device, 2nd Nightlight, 2nd project light, camera device, sound device etc.
[0053] From FIG. 2 and FIG. 2-2 and FIG. 2-3 can see Desktop embodiment power by AC, DC or adaptor, transfomer, USB, chemical, solar or market available power(s). Because the light output-areas need as large as possible so the said LED light will have some more space under the substrate-means so can add the other electric functions device may selected from group consideration including speaker, audit device, video device, camera device, recorder device, speaker, sensor means, switch means, remote control device, Bluetooth device, power device, USB charger device, AC outlets power device, digital data storage device, memory card device, memory storage device, energy storage device, batteries, transformer, adaptor, receptacle, outlets, adaprot, receiving device, sound device, speaker, night light device, power fail light device, water lighting device (Water dance, Water wave), Project device, light show device, project means, optics means, optics device, communication device to add on the current LED light has more than one Optics means to project light so can become multiple functions device which the added functions may in categories of electric, digital data device, communication device, computer related device, cellar phone related device and not limited to for current invention discussion. It is appreciated the co inventor's prior arts and co-pending filing still fall withih the scope of claims and discussion and concepts. Any equivalent function, alternative skills, update method still appreciated as the current invention as prior art.
[0054] From FIG. 2-1 can see Preferred 2nd Desk-Top device details has base+Big light output areas+motor/cam and electric parts & accessories to the LEDs light beam though the 1 st and 2 nd optics means within the tube-means to project light image to all desired areas from the Top big light output-areas which are much bigger than the LED light housing cross-section size.
[0055] From FIG. 1-6 , 1 - 7 , 1 - 8 disclosure the Detail construction of the 1st Embodiment for Plug-In type or Desk-Top type has preferrable power source to project light or image from lower position LEDs to 1st optics means with moving function by motor+gear set+cam means and light emit to 2nd Optis means which are fixed so can see the desired motion light or image functions, effects. From FIG. 1-6 show the Big Light-Output area/opening/windows
[0056] Which has bigger size than the LED light housing's cross section. This is the simple can explain from the Mathmatic and Physics theory (Slide) is bigger than the (other 2 sides length) for a triangle theory. The Light-output area/opening/window need as big as possible to make the more bigger image/light project through the Tube-means to the ceiling, walls. This is current invention required. The said LED light has longer length on the wall side and shorter length on the away from wall side. The bigger length difference will get more large (Slide area/opening/window) so can project more light to more wider areas. This is the current invention very important to get ( 1 ) As big as possible for Light-Output area/opening/window so can project light to as larger as possible ( 2 ) The LED light unit has longer length on wall side and shorter length for LED light away from the wall side ( 3 ) The LED light has as compact as possible for housing but as larger as possible of the Light-output area/opening/window. This is the current invention make major features than Any other bulky or Bow like prior arts.
[0057] The LED project light has more than one Optics-means which has the Plug-In type has the prong means to connect with outlets from wall, extension cord, power stating, desk lamp outlets receptacles. The LED project light can project the light image to ceiling, walls, floor from the more than one optics-means construction. The optics-means has more than one Optics lens construction basing on the inner or outside has preferred texture so each become a optics-lens. The more than one of optics-means can project a splendid color image to all surrounding area because the current invention has construction of
(1) the inner built-in more than one LEDs. The LEDs may selected from group of color, specification, size, functions and each LED can has its emit direction, orientation, angle to anywhere because has more than one Optics-means as inventor's prior patented claims so the each LED light has different light emit direction even LED light emit angle is narrow but after the light beam been under more than one optics means, then, the light will come out from Big light-output areas/opening/windows . . . . (2) This is the result basing ( 1 ) More than one LEDs ( 2 ) more than one optics-means ( 3 ) Interchangeable power source ( 4 ) as inventor's all prior patents and co-pending all LED project light concept as above and below listed ( 9 ) co-pending and issued Prior arts.
[0060] Ser. No. 12/318,471, U.S. Ser. No. 12/318,470, U.S. Ser. No. 12/834,435 and also is continuous filing for co-inventor's prior filing cases as below issued patents:
U.S. Ser. No. 12/292,153 (now is U.S. Pat. No. 7,871,192), U.S. Ser. No. 12/232,505 (now is U.S. Pat. No. 7,832,917), U.S. Ser. No. 12/318,473 (now is U.S. Pat. No. 7,832,918). LED light has laser means U.S. Ser. No. 12/624,621 (Now is U.S. Pat. No. 8,303,150) LED project light for Seasonal items U.S. Ser. No. 12/771,003 (now is U.S. Pat. No. 8,408,736) Light device has More than one project means. U.S. Ser. No. 12/876,507 (now U.S. Pat. No. 8,083,377) Light device has projection function with focus adjustable and project means can change position U.S. Ser. No. 12/886,832 Digital data projection Light device, Sep. 8, 2010 filed U.S. Ser. No. 12/938,564 Laser projection light device, Nov. 4, 2010 filed U.S. Ser. No. 12/948,953 LED light has time projection. Nov. 13, 2010 filed. U.S. Ser No. 13/021,107 LED light has 3Dimensional projection, Feb. 4, 2011 filed.
[0071] Above listed Projection light device total has (9) projection light device are parent filing cases as CIP filing of the current invention.
[0072] From FIG. 1 , FIG. 1-1 , 1 - 2 show the Alternative Current (AC) power units which has the AC adaptor, transformer, AC wires to connect with units to get make the LED project light to have splendid project light image to be seen.
[0073] From FIG. 2 , FIG. 2-1 , FIG. 2-2 , FIG. 2-3 and Show the Direct Current (DC) power unit which can have power from any Direct current device such as batteries, energy storage means, solar power, wind power, chemical power.
[0074] It is appreciated for the Interchangeable power source as the inventor prior art as above listed U.S. Pat. No. 8,434,927.
[0075] From FIG. 1 , FIG. 1-1 , 1 - 2 show the Plug-In type LED light device with base are install on the Plug-In housing to make the Alternative Current (A.C.) to drive the inner circuit means, LEDs, Sensor means, switch means, control means, and optional motor means to project the image to ceiling/walls/floor has plenty of color and moving (If add the motor means).
[0076] Although specific preferred embodiments of the current invention are described above, it is to be appreciated that all alternative, equivalent, same-function and/or same-skill-or-theory variations, modifications, replacements, arrangements, or constructions may still fall within the current scope of the invention. | An LED night light having different power sources including a battery, outlet plug-in power source, or interchangeable power source incorporates geometric shape optics means(es) has more than one OPTICS means(es) which has relative positions, distances, and/or orientations to create plurality of light beams Passing though by more than one OPTICS means(s), so the light beam(s) of the said LED or LEDs will pass though the said more than one optics means(es) and project to surface(s) surrounding including ceiling, walls, floor and all desire areas. At least one of the optics means has optics-properties on its surface(s) to permit the plurality of LED or LEDs light beam(s) passing through the optics means and passing though plurality optics means to create the motion or color image while incorporate with control means and IC means. The LED device has slid surface which allow the narrow housing but with maximum light-output area to offer the maximum light beams to be seen on locations because the Big Light-Output area which are bigger than the LED light device housing's cross-section surface. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to a material-guiding device in an agricultural apparatus and to a mower-conditioner.
BACKGROUND OF THE INVENTION
[0002] EP 1008 290 discloses a conditioner-tedder having a conditioning plate, which regionally surrounds a conditioning rotor, and a swath plate, with which the discharged material flow can be diverted onto the ground and thus be more narrowly or more widely deposited. When the conditioning plate is adjusted, the direction of discharge onto the swath plate also changes, which latter must then be readjusted accordingly.
[0003] From WO A12004/105462, a comparable mowing and processing apparatus is known, in which the conditioning plate is followed by a plate which is either pressed under spring force against the conditioning plate and remains against the latter even when it is adjusted, at the same time adjusting in inclination, or which serves as a swath plate and remains in a single position irrespective of the adjustment of the conditioning plate.
[0004] The problem on which the invention is founded can be seen in the fact that an adjustment of the conditioning plate has an effect upon the swath plate.
SUMMARY OF THE INVENTION
[0005] According to the present invention, there is provided a mower-conditioner including a material guiding device including upstream- and downstream-situated portions which are each adjustable, with the downstream situated portion being adjusted jointly with the upstream portion such that a relative position between the two portions remains substantially constant.
[0006] In this way, the position of the downstream-situated portion, for example a swath plate, can be constantly adapted to the change in the upstream-situated portion, for example a conditioning plate, such that the transition, for example an angle, a distance and the like, can be altered as little as possible and the material flow is uniformly conveyed. The joint adjustment can be realized, for example, by a mechanical or hydraulic linkage or by a rigid, albeit adjustable, connection. The portions can be configured as a plate, a rake, rollers or the like.
[0007] If the one portion is directly connected to the other portion and moves with this, or if both portions are attached to a joint carrier, the position of which changes with the adjustment of the one portion, a joint adjustment of the two portions is likewise realized.
[0008] The effect upon the material flow can be altered if the portions are themselves adjustable, in which case they can also adopt a different spatial relationship relative to each other. The swath width and/or conditioning effect can thus be altered.
[0009] A manual actuating device for the adjustment of the portions can include levers, cranks, linkages and the like; a motor-operated actuating device can use electric or hydraulic motors, which are activated by an operator or by means of a control device in dependence on harvesting parameters, presets etc. If the actuating device(s) is/are located on the carrier, nothing changes in terms of their spatial relationship to the portions when adjustment takes place; alternatively, the actuating devices can be fitted separately from the housing and be connected to the portions via Bowden cables, lines or the like.
[0010] If an axis about which the carrier is pivotable, and an axis about which the downstream-situated portion is pivotably mounted on the carrier, are directly adjacent, the least possible change in the transition between the two portions occurs.
[0011] Since the material flow guidance in a mower-conditioner is critical to the material being nicely deposited, it is of great advantage to provide an appropriate material-guiding device close to the circumferential sub-region of a processing rotor. The material-guiding device according to the invention can also, however, be provided on other agricultural apparatuses, for instance on straw-choppers or on flail forage harvesters, i.e., anywhere where a rotor guides material and discharges it, guide plates being able to be provided, the portions of which act upon the material in the receiving and delivery region.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In the drawing, an illustrative embodiment of the invention, which is described in greater detail below, is represented, wherein:
[0013] FIG. 1 is a diagrammatic left side view of an agricultural apparatus in the guise of a mower-conditioner having a material-guiding device, and
[0014] FIG. 2 shows the material-guiding device according to FIG. 1 with a number of details.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] An agricultural apparatus 10 , shown in FIG. 1 , is configured as a so-called mower-conditioner or tedder, which is known per se, and is provided with a housing 12 , a chassis 14 , a drawbar 16 , a cutter bar 18 , a rotor 20 acting as a processing rotor, and a material-guiding device 22 .
[0016] With reference to FIG. 2 , it can be seen that the material guiding device 22 is located opposite the left upper quadrant of the rotor 20 and, in this illustrative embodiment, includes a carrier 24 , an upstream-situated portion 26 , a downstream-situated portion 28 and an adjustment arrangement for the guiding device 22 including a first actuating device 30 for the upstream-situated portion 26 and a second actuating device 32 for the downstream-situated portion 28 .
[0017] The function of the material-guiding device 22 consists in firstly holding mown material in engagement with the rotor 20 and squeezing it into a gap between the rotor 20 and the first or upstream-situated portion 26 , so that the non-homogeneous material rubs together and is prepared for the drying process. After this, the material, once it is able to detach itself from the rotor 20 , is intended either to fly straight rearwardly, until it falls onto the ground, or until it engages, and is directed from, the second or downstream-situated portion 28 onto the ground. Both functions can be exercised more or less strongly.
[0018] The carrier 24 actually consists of a frame, having respectively an end web 34 and similar intermediate webs (not shown), which are rigidly connected to one another by means of cross struts. On their side facing the rotor 20 , the end webs 34 are curved in accordance with a cylindrical path traced by outer ends of crop material engaging elements of the rotor 20 , and extend over about ninety angular degrees. In the upper, rear end region of the end webs 34 can be found front and rear bearings 36 and 38 , respectively. The front bearing 36 is at the same time located on the housing 12 and serves for the pivotable mounting of the carrier 24 on the housing. The rear bearing 38 serves for the vertical pivotable mounting of the downstream-situated portion 28 on the carrier 24 . The axes of the bearings 36 , 38 run parallel to each other and to the rotational axis of the rotor 20 . The two bearings 36 , 38 lie directly next to each other, in any event insofar as the actual circumstances permit, in order to accommodate the parts. The bearings 36 , 38 can be configured as rods, hinges, screws, journals or the like.
[0019] The front, i.e., upstream-situated portion 26 is formed as a bent metal plate, along which the material flow can slide and which is fitted—screwed or welded—to the bottom side of the carrier 24 . The downstream-situated edge of the upstream-situated portion 26 extends as far as the downstream-situated portion 28 , yet continues to maintain a distance thereto so that the latter can still be pivoted. The portion 26 can also extend beyond the upstream-situated end of the carrier 24 and is there provided, as usual, with a skirt.
[0020] The rear, i.e., downstream-situated portion 28 is of substantially flat configuration and in this illustrative embodiment occupies only about one-fifth of the length of the upstream-situated portion 26 which directly adjoins the portion 28 . Whilst the front portion 26 is pivotable only through a few degrees, the rear portion 28 can be pivoted through almost 90 degrees towards or away from the rotor 20 . Between the two portions 26 and 28 , an angle α is always obtained.
[0021] The first actuating device 30 is configured as a crank-linkage assembly, which is attached, preferably movably, on the one hand to the housing 12 , and, on the other hand, to the carrier 24 and thus also to the front portion 26 . As soon as the actuating device 30 is extended or retracted, for example, the position of the front portion 26 changes relative to the rotor 20 . On the actuating device 30 or on the carrier 24 , an indicator can be provided, so that an operator can tell how far the portion 26 is away from the cylindrical path traced by the radially outer ends of the crop material engaging elements of the rotor 20 .
[0022] The second actuating device 32 is configured as a lever-linkage assembly and is disposed on the carrier 24 , i.e., it moves with the latter. The actuating device 32 is equipped with a lever-latch mechanism 40 , with which the second, downstream-situated portion 28 can be pivoted about the second bearing 38 . the second portion 28 is held in a predetermined position, which can be recognized by the position of the lever-lath mechanism 40 .
[0023] In principle, the first and/or the second actuating device 30 and/or 32 could also be located on the chassis 14 or its frame and act upon the carrier 24 , or the portions 26 , 28 , via Bowden cables or the like.
[0024] After all this, the following working is obtained.
[0025] The upstream-situated portion 26 is located on the bottom side of the carrier 24 , and the downstream-situated portion 28 is located with the second actuating device 32 on the rear end region of the carrier 24 . Depending on the position of the lever-latch mechanism 40 , a certain angle α is obtained between the two portions 26 , 28 . When the first actuating device 30 is actuated, the carrier 24 , together with the two portions 26 , 28 , pivots about the front bearing 36 , the angle α, and thus the material flow characteristics, remaining unaltered.
[0026] Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. | A material-guiding device in a mower-conditioner surrounds an upper front region of a crop processing rotor and is composed of an upstream-situated portion and a downstream-situated portion. The downstream-situated portion is adjustable relative to the upstream situated portion and is connected thereto such that the adjustment of the upstream-situated portion simultaneously leads to an adjustment of the downstream-situated portion, such that an adjustable angle α present between the two portions is maintained and thus a uniform material flow is enabled. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to high voltage circuits. More specifically, the present invention relates to high voltage circuits in an electronic erasable programmable read only memory (EEPROM) integrated circuit (IC).
2. Related Art
Metal-oxide semiconductor field effect transistors (MOSFETs) are manufactured such that they can withstand a particular maximum voltage across any two terminals of the MOSFET. A MOSFET having a maximum voltage of V max is "rated" at a voltage of V max . The maximum voltage of a MOSFET is termed the breakdown voltage of the MOSFET. A common MOSFET breakdown voltage is equal to approximately twelve volts. As the rated voltage of a MOSFET increases the associated expense in manufacturing the IC containing the MOSFET increases. The increased manufacturing expenses may be particularly acute with p-channel MOSFETs. For example, in order to manufacture an IC containing a p-channel MOSFETs rated at twenty-four volts, a significant increase in process technology and materials is required when compared to an IC containing only twelve volt rated p-channel MOSFETs.
When operating an IC it is often necessary to apply a voltage greater than twelve volts to one or more MOSFETs in the IC. Typically, higher rated MOSFETs are used in ICs to which voltages greater than twelve volts are applied. However, as discussed above, the use of such higher rated MOSFETs are not always desirable since they are more difficult and more expensive to produce.
One type of circuit which, for proper operation, requires a maximum voltage greater than twelve volts is an electronic erasable programmable read only memory (EEPROM) circuit. A general description of an EEPROM circuit 100 and how it operates is given below with reference to FIG. 1.
The EEPROM circuit 100 includes an array of EEPROM cells 102, hereafter "memory cells". These memory cells 102 are non-volatile. In other words, each memory cell 102 can store a bit of dam for ten years or more. In addition, these memory cells 102 can be erased and programmed by a user. Typically, each memory cell includes a transistor. Nodes of the transistor are connected to a row line 104, a column line 108, an erase line 106, and a ground line 110. The operation of memory cell 102 will now be described with reference to FIG. 2, which shows one of the memory cells 102 in greater detail.
In order to properly function, a memory cell 102 is typically erased, programmed and then read based on instructions output by a controlling processor (not shown). When erasing a memory cell 102, a voltage of approximately twenty-two volts is applied to the erase gate 206 via the erase line 106. When erasing a memory cell 102, the row line 104 and the column line 108 are typically "low", i.e., approximately zero volts or ground. The high voltage applied to the erase gate 206 causes a positive charge to form on the floating gate 204 of the memory cell 102. This positive charge on the floating gate 204 effectively erases the memory cell 102. That is, the memory cell is considered to store a binary "zero" when the floating gate 204 stores a positive charge. Typically, all memory cells 102 are erased before the processor (not shown) requests that some memory cells 102 be programmed to store a binary "one".
Programming a memory cell 102 typically requires that a twelve volt signal be applied to the control gate 202 of the memory cell 102 via the row line 104 while a signal having a voltage between seven and eight volts is applied to the drain 210 of the transistor within the memory cell 102 via the column line 108. The source 208 of the transistor in the memory cell 102 is held to zero volts or ground. When these potentials are applied to the memory cell the positive charge stored in the floating gate 204 during the memory cell erase operation, described above, is reduced. When the charge stored by the floating gate 204 is below a predetermined level, the memory cell 102 is considered to store a binary "one". After erasing and programming the memory cells 102, the memory cells 102 can be read. Reading a memory cell 102 is generally accomplished by applying a voltage of approximately five volts to the control gate 202 of the memory cell 102 via the row line 104 and applying a voltage of approximately one and one-half volts to the drain. Further details regarding the operation and structure of an EEPROM will be apparent to persons skilled in the relevant art.
FIG. 3 illustrates an EEPROM IC 300. Typically, EEPROM ICs do not contain the VOLTAGE REGULATOR INPUT SWITCH 318. A processor (not shown) can request that the EEPROM IC 300 erase, program or read the memory cells 102 of an EEPROM circuit 100, as described above. The processor provides a V pp SIGNAL 302, a V dd signal 304, ERASE CONTROL SIGNALs 308, a READ-OR-PROGRAM SIGNAL 314, and a PROGRAM signal 326 to the EEPROM IC 300. The value of these signals varies depending upon which operation the processor requests.
To request the erasing of an EEPROM circuit 100, the processor (not shown) outputs a potential of approximately twenty-four volts on the V pp SIGNAL 302 and a potential of approximately five volts on the ERASE CONTROL SIGNAL 308 associated with the EEPROM circuit 100 to be erased. The V pp SIGNAL 302 and the ERASE CONTROL SIGNAL 308 are input into a HIGH VOLTAGE SWITCH 306, described below. The HIGH VOLTAGE SWITCH 306 outputs a voltage of approximately twenty-two volts to the ERASE LINE of the EEPROM circuit 100 on output line 310.
To request that memory cell 102 within an EEPROM circuit 100 be programmed, the processor (not shown) outputs a potential of approximately twelve volts on the V pp SIGNAL 302, a potential of approximately five volts on the V dd SIGNAL 304 and a potential of approximately five volts on the V pp SWITCH INPUT LINE 314. The V pp SWITCH 312 outputs a potential of approximately V pp volts on its output line 316 when the V pp SWITCH INPUT LINE 314 is high, i.e., the signal voltage is approximately five volts. As stated above, when programming the EEPROM circuit, V pp is approximately twelve volts. Typical EEPROM ICs do not include the VOLTAGE REGULATOR INPUT CIRCUIT 318 which in the present invention ensures that the VOLTAGE REGULATOR 324 input signal VPPZ will not have a voltage which exceeds twelve volts. Instead, the VPPZ SIGNAL 322 is input directly into VOLTAGE REGULATOR 324 along with the PROGRAM signal 326 and the V dd SIGNAL 304. When programming a memory cell 102, the VOLTAGE REGULATOR outputs a signal having a voltage between seven volts and eight volts on the VOLTAGE REGULATOR OUTPUT LINE 328. This output signal is sent to COLUMN PROGRAM CIRCUITS (not shown) within the EEPROM circuit 100.
As discussed above, to request that the EEPROM circuit 100 be read, the processor outputs a potential of approximately five volts on the V pp SIGNAL 302 and a potential of approximately five volts on the V dd SIGNAL 304. The detailed operation of the EEPROM IC 300 during a READ operation will be apparent to persons skilled in the relevant art.
In the typical EEPROM IC 300, the HIGH VOLTAGE SWITCH 306, the V pp SWITCH 312, and the VOLTAGE REGULATOR 324 will all be exposed to a potential of approximately twenty-four volts when the processor (not shown) requests that an EEPROM circuit 100 be erased, as described above. When a twenty-four volt potential is applied to a circuit, the high voltage circuits 306, 312, and 324 are typically designed such that some p-channel transistors within the high voltage circuits 306, 312, and 324 have a rating of, at least, twenty-four volts. A typical HIGH VOLTAGE SWITCH 306, V pp SWITCH 312, and VOLTAGE REGULATOR 324 will now be described in greater detail.
In FIGS. 4-6, a transistor having a circle at its control gate is a p-channel metal oxide semiconductor field effect transistor (MOSFET). If the transistor does not have a circle at its control gate then it is an n-channel MOSFET. If the MOSFET has an "X" it its channel then it is a twenty-four volt rated MOSFET, otherwise it is a twelve volt rated MOSFET. If the back-gate connection is not explicitly shown, it is connected to V ss , or ground, if the transistor is an n-channel MOSFET or to V pp if the transistor is a p-channel MOSFET.
FIG. 4 illustrates a schematic of a typical HIGH VOLTAGE SWITCH 306. Transistors 402, 406, and 408 are each n-channel MOSFETs which are rated at twenty-four volts. Transistor 404 is a p-channel MOSFET rated at twenty-four volts. Additionally, transistor 404 is a "weak" transistor, i.e., when the transistor conducts it has a high resistance.
There can be many EEPROM circuits 100 in an EEPROM IC 300. A HIGH VOLTAGE SWITCH 306 is typically associated with each EEPROM circuit 100, as shown in FIG. 3. To request that an EEPROM circuit be erased, the processor (not shown) outputs a twenty-four volt potential on the V pp SIGNAL 302, as described above. When the input signal voltage, IN, is "high", i.e., approximately five volts, the output signal 310 voltage of the HIGH VOLTAGE SWITCH 306 is approximately equal to V ss . When the input signal voltage, IN, is "low", i.e. approximately zero volts, the output signal voltage of the HIGH VOLTAGE SWITCH 310 is approximately equal to: V pp minus the threshold voltage of transistor 406. Transistor threshold voltages are described below. Further details pertaining to the structure and operation of the circuit shown in FIG. 4 will be apparent to persons skilled in the relevant art.
The reason why the p-channel MOSFET 404 which is rated at twenty-four volts 404 is used in this circuit shall now be described. If the input, IN, is "high", MOSFET 402 conducts, thereby pulling the voltage on node N10 down to approximately zero volts. Simultaneously, p-channel MOSFET 404 also conducts, since its gate input voltage, i.e., five volts, is significantly less than its drain voltage, i.e., twenty-four volts. However, because transistor 404 is a weak device, as described above, transistors 404 and 402 will act as a voltage divider having a significant voltage drop across transistor 404. Therefore, the voltage at node N10 will be close to zero volts. In this situation, the voltage drop across the p-channel transistor 404 is approximately twenty-four volts. Therefore, transistor 404 must be rated at a minimum of twenty-four volts in order to prevent transistor 404 from breaking-down.
The HIGH VOLTAGE SWITCH circuit 306 could alternatively be designed using a well known charge-pump circuit (not shown). Such a circuit does not require a p-channel MOSFET rated at twenty-four volts. However, the circuit does require n-channel MOSFETs rated at twenty-four volts whose characteristics, e.g., threshold voltage, are known with high precision. Such n-channel transistors are expensive to manufacture and, therefore, circuits requiring such precise transistors are not desirable.
As stated above, it is often unacceptable to design a circuit within an EEPROM IC 300 which requires the use of p-channel MOSFETs rated higher than twelve volts. Therefore, a circuit performing the same functions as the HIGH VOLTAGE SWITCH 306, described above, which does not employ any p-channel MOSFETs rated higher than twelve volts is desirable.
FIG. 5 is a schematic of a typical V pp SWITCH 312. Transistor 502 is a twenty-four volt rated p-channel MOSFET. Transistors 504 and 506 are twenty-four volt rated n-channel MOSFETs. Transistor 508 is a twelve-volt rated p-channel MOSFET. Additionally, transistor 508 is a weak transistor.
The V pp SWITCH 312 outputs a voltage signal VPPW which is equal to the voltage of the V pp , SIGNAL 302 when the V pp SWITCH input, IN 314, is high. The input, IN 314, is high only when the processor has requested that the EEPROM circuit 100 be programmed or read. That is, when the processor requests that an erase be performed on the EEPROM circuit 100, and consequently the voltage on the V pp SIGNAL 302 is approximately twenty-four volts, the input, IN 314, is low. When the input, IN, is low, the output signal VPPW is approximately equal to the voltage on the V dd SIGNAL 304, i.e., five volts. Further details pertaining to the structure and operation of the circuit shown in FIG. 5 will be apparent to persons skilled in the relevant art.
As stated above, when the V pp SWITCH input, IN 314, is low, and V pp SIGNAL 302 has a voltage of approximately twenty-four volts, the voltage of the output signal VPPW is equal to V dd , i.e., approximately five volts. Therefore, the voltage drop across the source and the drain of transistor 502, and across the control gate and the drain of transistor 502 is approximately nineteen volts, i.e., (V pp -V dd ). Therefore, transistor 502 must be rated above twelve volts in order to prevent the transistor 502 from breaking down.
The V pp SWITCH 312 could alternatively be designed using a well known charge-pump circuit (not shown). Such a circuit does not require a p-channel MOSFET rated at twenty-four volts. However, the circuit does require n-channel MOSFETs rated at twenty-four volts whose characteristics, e.g., voltage threshold, are known with high precision. Such n-channel transistors are expensive to manufacture and are, therefore, undesirable.
As stated above, it is often unacceptable to design a circuit within an EEPROM IC 300 which requires the use of a twenty-four volt rated p-channel MOSFET. Therefore, a circuit performing the same functions as the V pp SWITCH 312, described above, which does not employ any p-channel MOSFETs rated higher than twelve volts is desirable.
A typical VOLTAGE REGULATOR 324 is shown in FIG. 6A and FIG. 6B. FIG. 6A is the portion of the VOLTAGE REGULATOR 324 which performs the functions of the VOLTAGE REGULATOR INPUT CIRCUIT 318 illustrated in FIG. 3. The output VPPZ is input into the portion of the VOLTAGE REGULATOR 324 shown in FIG. 6B. Transistors 602, 604, 606 and 608 are twenty-four volt rated p-channel MOSFETs. Transistors 610, 612 and 614 are twenty-four volt rated n-channel MOSFETs. Transistor 618 is a twelve volt rated p-channel MOSFET. Device 616 is an inverter.
FIG. 6A illustrates a logic circuit which has as its input, IN, a NOT-PROGRAM signal, i.e., the inverted PROGRAM signal 326. When the input, IN, is high, a voltage of twenty-four volts can be input into the circuit via the V pp SIGNAL 302. In this situation the circuit shown in FIG. 6A will output a twelve volt signal at node VPPZ. When the input, IN, is low, a voltage of twelve volts, V pp , must be input into the circuit via V pp SIGNAL 302. In this situation the circuit shown in FIG. 6A will output a twelve volt signal at node VPPZ. Further details pertaining to the structure and operation of the circuit shown in FIG. 6A will be apparent to persons skilled in the relevant art.
The twenty-four volt rated p-channel MOSFETs 602, 604, 606, and 608 are used in FIG. 6A because the voltage across their source and drain can be above twelve volts. For example, when the input, IN, is high, i.e., approximately five volts, and the V pp SIGNAL voltage is twenty-four volts, transistor 602 conducts. The difference between the transistor's 602 drain voltage and the transistor's 602 control gate voltage is approximately nineteen volts, i.e., (V pp -V dd ). Therefore, transistor 602 must be rated above twelve volts in order to prevent the transistor from breaking-down.
As stated above, it is often unacceptable to design a circuit within an EEPROM IC 300 which requires the use of p-channel MOSFETs rated above twelve volts. Therefore, a circuit performing the same functions as the VOLTAGE REGULATOR 324 described above, which does not employ any p-channel MOSFETs rated higher than twelve volts is desirable.
The VOLTAGE REGULATOR 324 shown in FIG. 6B provides an output signal V7 having a voltage between seven volts and eight volts when the processor (not shown) requests that a programming operation be performed on an EEPROM circuit 100. Transistors 632 and 634 are five volt rated n-channel MOSFETs. The remaining transistors are twelve volt rated n-channel MOSFETs. Blocks 620 and 636 are well known voltage dividers. No twenty-four volt rated MOSFETs are necessary since the input, VPPZ, never exceeds twelve volts because VPPZ is output from the circuit illustrated in FIG. 6A which limits the voltage on the VPPZ signal.
The VOLTAGE REGULATOR 328 inputs the PROGRAM signal 326, shown as INX in FIG. 6B. The input, INX, is high when the processor (not shown) requests that a memory cell be programmed, as discussed above. The VOLTAGE REGULATOR output signal V7 has a voltage between seven volts and eight volts when the input, INX, is high. The transistors 622-630 of the voltage divider 620 are chosen such that the size, and therefore, the resistance between the drain and the source, of transistor 622 when compared to the size of transistors 624-630 enables the output signal V7 voltage to be within the acceptable output range, i.e., between seven volts and eight volts. Threshold voltages can vary between transistors on different integrated circuit chips, even when the transistors have the same nominal threshold voltage.
Transistor 622 is manufactured having a nominal threshold voltage, e.g., 2.5 volts. In an n-channel MOSFET, the transistor 622 conducts if a control gate voltage is at least one threshold voltage V TH above the source voltage of the transistor, i.e., the voltage on signal V7. As discussed above, the threshold voltage can vary from the nominal threshold voltage. The output signal V7 voltage is affected by the threshold voltage variations in transistors 622 and 640. A VOLTAGE REGULATOR 322 which is more independent of threshold voltage variations of individual transistors is desirable. Further details pertaining to the structure and operation of the VOLTAGE REGULATOR of FIG. 6A and 6B will be apparent to persons skilled in the relevant art.
What are required are a HIGH VOLTAGE SWITCH, a V pp SWITCH, and a VOLTAGE REGULATOR INPUT CIRCUIT for use in an EEPROM IC 300 which do not require the use of a p-channel MOSFETs rated above twelve volts. In addition, what is needed is a VOLTAGE REGULATOR which more precisely regulates its output voltage when the MOSFETs which comprise the VOLTAGE REGULATOR have threshold voltages which deviate from their nominal threshold voltages.
SUMMARY OF THE INVENTION
The present invention is a plurality of circuits for receiving a high-voltage signal and for generating an output signal based on a received control signal, on an electronic erasable programmable read only memory (EEPROM) integrated circuit (IC). The plurality of circuits each having p-channel metal-oxide semiconductor field effect transistors (MOSFETs) whose breakdown voltage does not exceed twelve volts. The circuits including a high-voltage switch, a switch, and two voltage regulators.
A high-voltage switch for receiving a driver signal and a control signal. The high-voltage switch generates an output signal having a voltage not exceeding twelve volts when the control signal voltage is approximately equal to a first value, and wherein the output signal has a voltage exceeding twelve volts when the control signal voltage is approximately equal to a second value and when the driver signal exceeds twelve volts.
A switch for receiving a first driver signal and a control signal. The switch generates an output signal on an output having a voltage not exceeding twelve volts. The output signal equal to the first driver signal when the control signal voltage is approximately equal to a first value. The output signal equal to a second driver signal, having a voltage less than twelve volts, when the control signal voltage is approximately equal to a second value.
A voltage regulator for receiving a driver signal and a control signal, and for generating an output signal having a voltage not exceeding twelve volts.
A voltage regulator for receiving a driver signal and a control signal, and for generating an output signal having a voltage approximately equal to a first voltage when the control signal voltage is approximately equal to a first value.
BRIEF DESCRIPTION OF THE FIGURES
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying drawings, wherein:
FIG. 1 is a schematic of the EEPROM circuit according to a preferred embodiment.
FIG. 2 is a schematic of the memory cell according to a preferred embodiment.
FIG. 3 is an illustration of the EEPROM integrated circuit (IC) according to a preferred embodiment.
FIG. 4 is a schematic of a typical HIGH VOLTAGE SWITCH.
FIG. 5 is a schematic of a typical V pp SWITCH.
FIG. 6A is a schematic of a section of a typical VOLTAGE REGULATOR which performs the function of a VOLTAGE REGULATOR INPUT CIRCUIT.
FIG. 6B is a schematic of a typical VOLTAGE REGULATOR.
FIG. 7 is a schematic of the HIGH VOLTAGE SWITCH according to a preferred embodiment.
FIG. 8 is a schematic of the V pp SWITCH according to a preferred embodiment.
FIG. 9 is a schematic of the VOLTAGE REGULATOR INPUT CIRCUIT according to a preferred embodiment.
FIG. 10 is a schematic of the VOLTAGE REGULATOR according to a preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the present invention is now described with reference to the figures where like reference numbers indicate identical or functionally similar elements. Also in the figures, the left most digit of each reference number corresponds to the figure in which the reference number is first used. While specific steps, configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the relevant art will recognize that other steps, configurations and arrangements can be used without departing from the spirit and scope of the invention.
In the figures, a transistor having a circle adjacent to the control gate is a p-channel metal oxide semiconductor field effect transistor (MOSFET). If the transistor does not have a circle adjacent to the control gate then it is an n-channel MOSFET. If the MOSFET has an "X" in its channel, then it is a twenty-four volt rated MOSFET, otherwise it is a twelve volt rated MOSFET. If the back-gate connection is not explicitly shown, it is connected to V ss or ground if the transistor is an n-channel MOSFET or to V pp if the transistor is a p-channel MOSFET. A suggested width and length of the channel of each transistor are labeled adjacent to the transistor in microns (μ). If only one number is given, the number represents the suggested width of the transistor. The suggested length of such transistors is 0.9μ.
The present invention is directed to an EEPROM IC 300 having a number of innovative high voltage components. The high voltage components include a HIGH VOLTAGE SWITCH, a V pp SWITCH, and a VOLTAGE REGULATOR INPUT CIRCUIT for use in an EEPROM IC 300 which do not require the use of a p-channel MOSFETs rated above twelve volts. In addition, the present invention is directed to an EEPROM IC 300 having a VOLTAGE REGULATOR which more precisely regulates its output voltage when the MOSFETs which comprise the VOLTAGE REGULATOR have threshold voltages which deviate from their nominal threshold voltages.
FIG. 3 is a block diagram of an EEPROM IC 300 according to a preferred embodiment of the present invention. As discussed above, the EEPROM IC 300 include a number of innovative high voltage components, including a HIGH VOLTAGE SWITCH 306, a V pp SWITCH 312, a VOLTAGE REGULATOR INPUT CIRCUIT 318, and a VOLTAGE REGULATOR 324. These circuits will now be discussed.
While the high voltage components of the present invention are described herein with respect to an EEPROM IC 300, it should be understood that these high voltage components can be used with any other IC in which signals having high voltages are manipulated.
High Voltage Switch
The HIGH VOLTAGE SWITCH 306 of the present invention shall now be described with reference to FIG. 7. A conventional HIGH VOLTAGE SWITCH 306 which uses twenty-four volt rated p-channel MOSFETs is described above with reference to FIG. 4. As stated above, a circuit designed using twelve volt rated p-channel MOSFETs is preferable to a circuit designed using twenty-four volt rated p-channel MOSFETs. The present invention alleviates the need for p-channel MOSFETs rated above twelve volts in a HIGH VOLTAGE SWITCH 306.
The HIGH VOLTAGE SWITCH 306 of the present invention outputs a signal, VPPX, which has a voltage of approximately twenty-two volts when the HIGH VOLTAGE SWITCH input 306, IN, is low and the voltage on the V pp SIGNAL 302 is twenty-four volts. When the input, IN, is high, the output signal, VPPX, has a voltage close to zero volts or ground. The HIGH VOLTAGE SWITCH 306 of the present invention will now be described in greater detail.
Transistors 402, 406 and 408 are each twenty-four volt rated n-channel MOSFETS, as described in FIG. 4. The twenty-four volt rated p-channel MOSFET 404 of FIG. 4 is replaced with twelve volt rated p-channel MOSFETs 710, 712, and 714, and biasing circuits 702, and 704. Biasing circuit 702 is a well known voltage divider circuit which outputs a voltage signal on node N3 and a voltage signal on node N4. Biasing circuit 704 is a well known voltage divider circuit which outputs a voltage signal on node N15. Generating biasing voltages is well known. Preferably, biasing circuit 702 generates the voltages at nodes N3 and N4 after receiving the V pp SIGNAL 302.
The biasing circuit 702 is designed such that an approximately equal voltage drop occurs across each transistor within the biasing circuit. Therefore, the voltage at node N3 is equal to five-sevenths of the voltage on the V pp SIGNAL 302. Similarly, the voltage at node N4 is equal to four-sevenths of the voltage on the V pp SIGNAL 302.
The biasing circuit 704 operates in a manner similar to biasing circuit 702. However, there are some differences between the two biasing circuits 702, 704. When the input, IN is low, transistor 716 does not conduct. Therefore, transistor 718 and transistor 720 do not provide node N15 with a path to ground. Therefore, when the input IN is low the voltage on node N15 is unaffected by transistors 718 and 720. When the input IN is low the voltage on node N15 is approximately equal to one-half the voltage on the V pp SIGNAL 302. When the input, IN is high, transistor 716 conducts. The series resistance of transistors 718 and 720 are significantly less than the series resistance of transistors 728, 730 and 732. The resistance between node N15 and node N30 is therefore, greater than the resistance between node N15 and N32. Consequently, when the input IN is high the voltage at node N15 decreases since a greater percentage of voltage drops across transistors 722, 724 and 726.
The voltage signal on node N3 provides a biasing voltage to transistor 710. The voltage signal on node N4 provides a biasing voltage to transistor 712. The voltage signal on node N15 provides a biasing voltage to transistor 714.
The HIGH VOLTAGE SWITCH input, IN, is low only when the processor requests that a portion of the EEPROM circuit 100 associated with the HIGH VOLTAGE SWITCH 306 be erased. As described above, in order to erase a memory cell 102 within an EEPROM circuit 100, a voltage of approximately twenty-two volts must be applied to the erase gate 206 of the memory cell 102. The HIGH VOLTAGE SWITCH 306 supplies this twenty-two volt signal to the EEPROM circuit 100 when the input, IN is low. When the input, IN, is high, the signal at the HIGH VOLTAGE SWITCH output VPPX has a voltage of approximately zero volts or ground.
A unique aspect of the HIGH VOLTAGE SWITCH 306 as shown in FIG. 7 is that at no time will the voltage across any two terminals of a p-channel MOSFET be larger than twelve volts. Therefore, the highest rated p-channel MOSFET required in the HIGH VOLTAGE SWITCH 306 of the present invention is rated at twelve volts. How the HIGH VOLTAGE SWITCH 306, illustrated in FIG. 7, accomplishes the required functions without requiring a p-channel MOSFET rated above twelve volts is described below.
In the preferred embodiment, there is no concern that a p-channel MOSFET will have a voltage differential greater than twelve volts when the V pp SIGNAL is twelve volts or less. In the present invention, the only situation where a p-channel MOSFET rated above twelve volts could even potentially be necessary is when the voltage on the V pp SIGNAL is greater than twelve volts. Therefore, the following analysis will focus on the situation when a twenty-four volt potential is applied to the HIGH VOLTAGE SWITCH 306 via the V pp SIGNAL.
When twenty-four volts are applied to the HIGH VOLTAGE SWITCH 306, the voltage divider 702 outputs a signal on node N3 having a potential of approximately 17.1 volts, i.e., (5V pp /7). In addition, the voltage divider 702 outputs a signal on node N4 having a potential of approximately 13.7 volts, i.e., (4V pp /7). The voltage divider 704 outputs a signal on node N15 having a voltage of approximately twelve volts, i.e., (V pp /2), when the input, IN, is low.
When the input IN is high, the voltage on node N15 is reduced due to the operation of transistors 718, and 720, discussed above, in the biasing circuit 704, which reduces the resistance between node N15 and ground which consequently reduces the voltage at node N15. Therefore, the voltage at node N15 will be less than twelve volts. The voltages at nodes N3, N4, and N15 are applied to the control gates of p-channel MOSFETs 710, 712 and 714 respectively. When the input IN is high, transistor 402 conducts, thereby pulling node N10 to ground. That is, transistor 402 acts a controllable shunt for pulling node N10 to ground when the input signal IN is high. Therefore, the voltage drop between node N30 and node N10 is approximately twenty-four volts. In the present invention the voltage drops across three p-channel transistors instead of one.
The three twelve volt rated p-channel MOSFETs 710, 712, and 714 are biased by the signals N3, N4 and N15, such that the voltage at node N8 is approximately sixteen volts and the voltage at node N9 is approximately eight volts. Therefore, no p-channel MOSFET in the HIGH VOLTAGE SWITCH 306 has a voltage greater than twelve volts across any of its terminals. As such, no p-channel MOSFET must be rated above twelve volts in the HIGH VOLTAGE SWITCH 306 of FIG. 7.
The presence of voltage dividers 702 and 704 and twelve-volt rated MOSFETs 710, 712, and 714 enable the HIGH VOLTAGE SWITCH 306 of FIG. 7 to receive a twenty-four volt signal without requiring a p-channel MOSFET rated above twelve volts.
Additional features pertaining to the operation of the HIGH VOLTAGE SWITCH 306 will be apparent to persons skilled in the relevant art based on FIG. 7, the above discussion, and general circuit theory.
V pp Switch
The V pp SWITCH 312 of the present invention shall now be described with reference to FIG. 8. A conventional V pp SWITCH 312 using twenty-four volt rated p-channel MOSFETs is described above with reference to FIG. 5. As stated above, a circuit designed using twelve volt rated p-channel MOSFETs is preferable to a circuit designed using twenty-four volt rated p-channel MOSFETs. The present invention alleviates the need for a V pp SWITCH 312 to utilize p-channel MOSFETs rated above twelve volts.
The V pp SWITCH 312 of the present invention outputs a signal, VPPW, which has a voltage which is approximately equal to the voltage on the V pp SIGNAL 302 when the V pp SWITCH input, IN, is high. When the input, IN, is low, the output signal, VPPW, has a voltage close to the voltage on the V dd SIGNAL 304 which is typically approximately five volts. The V pp SWITCH 312 will now be described in greater detail.
Transistors 504 and 808 are each a twenty-four volt rated n-channel MOSFET. Transistor 506 is a twelve volt rated n-channel MOSFET. The remaining transistors are each a twelve volt rated p-channel MOSFET. The twenty-four volt rated p-channel MOSFET 502 illustrated in FIG. 5 is replaced with voltage divider 804, voltage divider 806, n-channel MOSFET 808 and p-channel MOSFETs 810 and 812. Voltage dividers 804, 806 are well known circuits. Voltage dividers 804, 806 each operate in a manner similar to voltage divider 702, described above. As such it is apparent that voltage divider 804 outputs a signal on node N4 having a voltage approximately equal to one-half the voltage on V pp SIGNAL 302. Voltage divider 806 outputs a signal on node N10 having a voltage approximately equal to one-half the voltage on V pp SIGNAL 302.
As described above, the V pp SWITCH input, IN, is high only when the processor (not shown) requests that a portion of the EEPROM circuit 100 be programmed or read. Therefore, when an EEPROM circuit 100 is to be erased the input, IN, of the V pp SWITCH 312 is low. The V pp SWITCH 312 supplies a voltage equal to that on the V pp SIGNAL 302 when the V pp SWITCH input, IN, is high. Otherwise, e.g., when erasing, the V pp SWITCH output VPPW is approximately equal to V dd , i.e., approximately five volts.
A unique aspect of the V pp SWITCH 312 as shown in FIG. 8 is that at no time will the voltage across any two terminals of a p-channel MOSFET be larger than twelve volts. Therefore, the highest rated p-channel MOSFET required in the V pp SWITCH 312 of the present invention is rated at twelve volts. How the V pp SWITCH 312 illustrated in FIG. 8 accomplishes the required functions without requiring a p-channel MOSFET rated above twelve volts is described below.
In the preferred embodiment, there is no concern that a p-channel MOSFET will have a voltage differential of greater than twelve volts when the V pp SIGNAL is twelve volts or less. That is, the only situation in which a p-channel MOSFET rated above twelve volts could even potentially be required is when the voltage on the V pp SIGNAL is greater than twelve volts. Therefore, the following analysis will focus on the situation where a twenty-four volt potential is applied to the V pp SWITCH 312.
When twenty-four volts are applied to the V pp SWITCH 312 the V pp SWITCH input, IN, must be low because the EEPROM IC 300 is neither reading from an EEPROM circuit 100 nor programming to an EEPROM circuit 100. When the V pp SIGNAL voltage is approximately twenty-four volts, voltage divider 804 outputs a signal on node N4 having a potential of approximately twelve volts, i.e., (V pp /2). Simultaneously, voltage divider 806 outputs a signal onto node N10 having a voltage of approximately twelve volts, i.e., (V pp /2). When the V pp SWITCH input, IN, is low, the V pp SWITCH output, VPPW, is equal to approximately V dd , i.e., five volts. Therefore a voltage drop of approximately nineteen volts, i.e., (V pp -V dd ) can appear between node N30 and node N32 when the V pp SWITCH input is low and the voltage on V pp SIGNAL is twenty-four volts.
Two transistors, coupled in series, are between node N30 and node N32. When the V pp SWITCH input IN is low and the voltage on V pp SIGNAL 302 is twenty-four volts the voltage on node N16 is approximately twenty-four volts, because transistor 504 does not conduct. As such, transistor 810 does not conduct because the voltage at the control gate of p-channel transistor 810 is equal to the voltage at the p-channel transistor's 810 drain. As stated above, twelve volts are present at node N4. Therefore, a voltage drop of approximately twelve volts occurs between the drain and the source of transistor 810. Since the voltage at node N10 is approximately twelve volts, transistor 812 will not conduct because the voltage at the control gate of transistor 812 is equal to the voltage at the drain of the transistor 812. Since the voltage on output signal VPPW is equal to five volts, a voltage drop of approximately seven volts occurs between the drain and the source of transistor 812, i.e. between node N4 and node N32. Therefore, no p-channel MOSFET has a voltage greater than twelve volts across any of their terminals. As such, no p-channel MOSFET must be rated above twelve volts in the V pp SWITCH 312 of FIG. 8.
The presence of voltage dividers 802 and 804, n-channel transistor 808 and p-channel transistors 810, 812 enable the V pp SWITCH 312 of FIG. 8 to receive a twenty-four volt signal without requiring a p-channel MOSFET rated above twelve volts.
Additional features pertaining to the operation of the V pp SWITCH 312 will be apparent to persons skilled in the relevant art based on FIG. 8, the above discussion, and general circuit theory.
Voltage Regulator Input Circuit
The VOLTAGE REGULATOR INPUT CIRCUIT 318 of the present invention shall now be described with reference to FIG. 9. A conventional VOLTAGE REGULATOR INPUT CIRCUIT 318 using twenty-four volt rated p-channel MOSFETs is described above with reference to FIG. 6A. As stated above, a circuit designed using twelve volt rated p-channel MOSFETs is preferable to a circuit designed using twenty-four volt rated p-channel MOSFETs. The present invention alleviates the need for a VOLTAGE REGULATOR INPUT CIRCUIT 318 to utilize p-channel MOSFETs rated above twelve volts.
The VOLTAGE REGULATOR INPUT CIRCUIT 318 of the present invention outputs a signal, VPPZ, which has a voltage approximately equal to one half of that on the V pp signal when the VOLTAGE REGULATOR INPUT CIRCUIT input, IN, is high. When the input, IN, is low, and the voltage on the V pp SIGNAL 302 is twelve volts the output signal, VPPW, has a voltage of approximately twelve volts.
Transistor 614 is a twenty-four volt rated n-channel MOSFET. Transistors 610 and 612 are each a twelve volt rated n-channel MOSFET. The remaining transistors illustrated in FIG. 9 are each twelve volt rated p-channel MOSFETs. The twenty-four volt rated p-channel MOSFETs 602, 604, 606 and 608, illustrated in FIG. 6 are replaced with voltage divider 902, voltage divider 904, and p-channel MOSFET 906. Voltage dividers 902, 904 are well known circuits. Voltage dividers 902, 904 each operate in a manner similar to voltage divider 702, described above. As such it is apparent that voltage divider 902 outputs a signal on node N25 having a voltage approximately equal to five-sixths of the voltage of V pp SIGNAL 302. Voltage divider 904 outputs a signal on node N40 having a voltage approximately equal to one-half the voltage on V pp SIGNAL 302.
As described above, the VOLTAGE REGULATOR INPUT CIRCUIT input, IN, is low only when the processor (not shown) requests that a portion of the EEPROM circuit be programmed. Therefore, when an EEPROM circuit 100 is to be erased, the input, IN, of the VOLTAGE REGULATOR INPUT CIRCUIT 318 is high. The VOLTAGE REGULATOR INPUT CIRCUIT 318 supplies a voltage equal to one-half of the voltage present on the V pp SIGNAL 302 when the VOLTAGE REGULATOR INPUT CIRCUIT input, IN, is high. That is, the voltage at the output node VPPZ is approximately twelve volts when the input, IN, is high and the voltage of the V pp SIGNAL is twenty-four volts. When the input, IN, is low the VOLTAGE REGULATOR INPUT CIRCUIT output VPPZ is approximately equal to V pp , i.e., twelve volts.
A unique aspect of the VOLTAGE REGULATOR INPUT CIRCUIT 318 as shown in FIG. 9 is that at no time will the voltage across any two terminals of a p-channel MOSFET be larger than twelve volts. Therefore, the highest rated p-channel MOSFET required to be in the VOLTAGE REGULATOR INPUT CIRCUIT 318 of the present invention is rated at twelve volts. How the VOLTAGE REGULATOR INPUT CIRCUIT 318 illustrated in FIG. 9 accomplishes the required functions without requiring a p-channel MOSFET rated above twelve volts is described below.
In the preferred embodiment, there is no concern that a p-channel MOSFET will have a voltage differential of greater than twelve volts when the V pp SIGNAL 302 is twelve volts or less. The only situation where a p-channel MOSFET rated above twelve volts could even potentially be required by the VOLTAGE REGULATOR INPUT CIRCUIT 318 is when the voltage on the V pp SIGNAL is greater than twelve volts. Therefore, the following analysis will focus on the situation which occurs when a twenty-four volt potential is applied to the VOLTAGE REGULATOR INPUT CIRCUIT 318.
When twenty-four volts are applied to the VOLTAGE REGULATOR INPUT CIRCUIT 318, the V pp SWITCH input IN must be high, i.e., the EEPROM IC 300 is not programming, because the processor (not shown) only applies twenty-four volts to the EEPROM IC 300 when requesting that a memory cell 102 be erased. When the V pp SIGNAL 302 voltage is approximately twenty-four volts and the input, IN, is high, voltage divider 902 outputs a voltage on node N25 of approximately 20 volts, i.e., (5V pp /6), as discussed above. The signal at node N42 is low, therefore, transistor 614 does not conduct. The voltage on node N25, i.e., 20 volts, is applied to the gate of transistor 906 causing the transistor 906 to conduct. Since transistor 906 conducts the voltage on node N11 is approximately twenty-four volts. This voltage is applied to the gate of transistor 910. Since the voltage on the gate of transistor 910 is approximately equal to the voltage on its drain, transistor 910 does not conduct. The output voltage VPPZ is, therefore, equal to the output voltage of voltage divider 904 which is approximately twelve volts, i.e., (V pp /2), as discussed above. As is seen from the above analysis, no p-channel MOSFET has a voltage greater than twelve volts across any of its terminals. As such, no p-channel MOSFET must be rated above twelve volts in the VOLTAGE REGULATOR INPUT CIRCUIT 318 of FIG. 9.
The presence of voltage dividers 902 and 904 and p-channel transistor 906 enable the VOLTAGE REGULATOR INPUT CIRCUIT 318 of FIG. 9 to receive a twenty-four volt signal without requiring a p-channel MOSFET rated above twelve volts.
Additional features pertaining to the operation of the VOLTAGE REGULATOR INPUT CIRCUIT 318 will be apparent to persons skilled in the relevant art based on FIG. 9, the above discussion, and general circuit theory.
Voltage Regulator
The VOLTAGE REGULATOR 324 of the present invention shall now be described with reference to FIG. 10. A conventional VOLTAGE REGULATOR 324 is described above with reference to FIG. 6B. The present invention outputs a signal V7 having a potential between seven and eight volts when the processor requests that an EEPROM circuit 100 be programmed. The output signal V7 is received by COLUMN PROGRAM CIRCUITS (not shown) within the EEPROM circuits 100. When programming, the COLUMN PROGRAM CIRCUITS (not shown) apply the output signal V7 to the drain of a memory cell 210 via a column line 108. As discussed above, the voltage on the V7 signal, i.e., between seven and eight volts, is necessary to ensure that the memory cell 102 is programmed properly.
As described above, transistors have an inherent threshold voltage. In an n-channel MOSFET, the MOSFET conducts only if a gate voltage is at least one threshold voltage V TH above the source voltage of the MOSFET. A MOSFET is designed such that its nominal threshold voltage is known. However, these threshold voltages can vary from their nominal values. Typically, the variance from the nominal threshold voltage will be consistent between transistors located within the same IC. The VOLTAGE REGULATOR 324, illustrated in FIG. 6B, is affected by these variances in a MOSFET's threshold voltage. A feature of the present invention is that the VOLTAGE REGULATOR 324 minimizes the output signal's (V7) dependence on MOSFET threshold voltage variances.
FIG. 10 is a schematic of a VOLTAGE REGULATOR 324 according to a preferred embodiment of the present invention. As discussed above, the VOLTAGE REGULATOR 324 of the present invention outputs a signal, V7, which has a voltage between seven and eight volts when the VOLTAGE REGULATOR input, INX, is high. When the input, IN, is low, the output signal, V7, is unregulated.
Transistor 1002 is a weak, i.e., highly resistive, twelve volt rated p-channel MOSFET. Transistors 632 and 634 are five volt rated n-channel MOSFETs. The remaining transistors are twelve volt rated n-channel MOSFETs. Voltage dividers 620 and 636 are present in the IC and are well known circuits. Their function is described below.
As discussed above, the VOLTAGE REGULATOR input, INX, is high only when the processor (not shown) requests that a portion of the EEPROM circuit 100 is to be programmed. Therefore, when an EEPROM circuit 100 is to be read or erased, the input INX of the VOLTAGE REGULATOR 324 is low. When an EEPROM circuit 100 is being programmed the VOLTAGE REGULATOR INPUT CIRCUIT 318 supplies a twelve volt signal to the VOLTAGE REGULATOR 324 via signal VPPZ. As discussed above, the VOLTAGE REGULATOR 324 outputs a voltage between seven volts and eight volts on its output signal V7.
A unique aspect of the VOLTAGE REGULATOR 324, as shown in FIG. 10, is that its output voltage signal V7 is significantly more independent of variances in its transistor's threshold voltages than the VOLTAGE REGULATOR 324 illustrated in FIG. 6B. The VOLTAGE REGULATOR INPUT CIRCUIT 318 limits the input signal VPPZ voltage into the VOLTAGE REGULATOR 324 to twelve volts. Therefore, the voltage across any two terminals of a p-channel MOSFET located within the VOLTAGE REGULATOR 324 will not be larger than twelve volts. Consequently, the highest rated p-channel MOSFET required in the VOLTAGE REGULATOR INPUT CIRCUIT 318 of the present invention is rated at twelve volts.
As discussed above, the voltage of output signal V7 of VOLTAGE REGULATOR 324 is desired to be between seven volts and eight volts when the input, INX, is high. However, the output signal V7 of the VOLTAGE REGULATOR 324, as illustrated in FIG. 6B, is affected by threshold voltage variances of transistors 622 and 640. In the preferred embodiment of the present invention, the VOLTAGE REGULATOR 324, as illustrated in FIG. 10, outputs a signal V7 which does not significantly vary based upon the threshold voltage variation of transistor 640.
When the voltage on signal VPPZ is twelve volts and the input signal INX is high, transistors 632 and 634 conduct. As a result, voltage divider 636 is effectively coupled to ground. In the preferred embodiment, the nominal threshold of transistors 622 and 640 are approximately 2.5 volts. Without transistor 1002 the voltage at node NREG will be approximately 9.5 volts, i.e., (V pp -V TH ). The voltage at node NREG is applied to the gate of transistor 622. Transistor 622 pulls its source node up to approximately seven volts, i.e., (V NREG -V TH ). As discussed above, the actual threshold voltage can depart from the nominal threshold voltage. For example, the actual threshold voltage of transistors 622 and 640 can be three volts even though the nominal threshold voltage is 2.5 volts. In this situation the VOLTAGE REGULATOR 324, without transistor 1002, outputs a voltage of approximately six volts, i.e., (V pp -2V TH ), on signal V7 which is outside an acceptable voltage output range, i.e., between seven volts and eight volts.
In the preferred embodiment of the present invention transistor 1002 is coupled in parallel with transistor 640. The gate of transistor 1002 is coupled to ground. Therefore, transistor 1002 always conducts. As discussed above, transistor 1002 has a high resistance across its channel. When the threshold voltage of transistors 622 and 640 are actually three volts, as opposed to the nominal value of 2.5 volts, the voltage at node NREG would be approximately nine volts, if transistor 1002 were not present. When transistor 1002 is present, the transistor 1002 attempts to pull the voltage at node NREG to twelve volts. However, the remaining transistors in voltage divider 636 prevent the voltage at node NREG from reaching twelve volts. Transistor 1002 and voltage divider 636 are designed such that the voltage at node NREG is approximately ten volts, i.e., approximately one threshold voltage above the acceptable voltage output range. The voltage at node NREG is applied to the gate of transistor 622 causing it to conduct. The voltage on output signal V7 will be approximately 7 volts, i.e., (V NREG -V TH ). Therefore, the output voltage is within the acceptable output voltage range, i.e., between seven volts and eight volts.
The presence of transistor 1002 enables the VOLTAGE REGULATOR 324, as illustrated in FIG. 10, to output a voltage signal V7 within the acceptable output voltage range. The voltage on output signal V7 is within the acceptable output voltage range even when transistors 622 and 640 have threshold voltages that vary from their nominal threshold voltages.
Additional features pertaining to the operation of the VOLTAGE REGULATOR 324 will be apparent to persons skilled in the relevant art based on FIG. 10, the above discussion, and general circuit theory.
While the invention has been particularly shown and described with reference to a preferred embodiment and several alternate embodiments thereof, it will be understood by persons skilled in the relevant art that various change in form and details can be made therein without departing from the spirit and scope of the invention. | A high voltage circuit for an electronic erasable programmable read only memory (EEPROM) integrated circuit (IC) is implemented using lower voltage semiconductor components. In the preferred embodiment, the circuit is capable of switching a twenty-four volt signal using p-channel metal-oxide semiconductor field effect transistors (MOSFETs) with a rated breakdown voltage not exceeding twelve volts. In the preferred embodiment, the circuit switches a driver signal in response to a first control signal. The circuit includes a first switch, connected between ground and an output, for selectively connecting the output to ground in response to the first control signal; a second switch, connected between the driver signal and the output for selectively connecting the driver signal to the output in response to a second control signal; a third switch for receiving the driver signal and the first control signal and for generating the second control signal, where the third switch includes a plurality of transistors and the driver signal is distributed across the plurality of transistors so that the driver signal is not across any single transistor; and a voltage divider circuit for dividing the driver signal into a plurality of lower voltage signals for controlling the third switch, wherein a magnitude of at least one of the lower voltage signals is controlled by the first control signal. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a sheet transporting apparatus, and particularly to the correction of the position of a sheet in the cross direction thereof perpendicular to a sheet transport direction and the correction of the skew feed posture of the sheet relative to the sheet transport direction.
[0003] 2. Description of the Related Art
[0004] In an image forming apparatus such as a copying machine, or an image reading apparatus, a registration (skew feed correction) device for the posture correction and alignment of a sheet being transported is provided immediately before the image forming portion or the image reading portion thereof. As such a registration device, there is, for example, an active registration system for correcting the skew feed of a sheet while transporting the sheet. This system is such that two original detecting sensors are disposed in a sheet transport path in the cross direction (hereinafter referred to as the main scan direction) of the sheet perpendicular to a sheet transport direction, and detect the skew of the leading edge of the sheet on the basis of a signal produced by the leading edge of the sheet crossing the respective sensors, and also the sheet transporting speed of skew feed correction rollers (hereinafter referred to as the registration rollers) disposed in the main scan direction and drivable independently of each other is controlled to thereby correct the skew feed of the sheet.
[0005] According to this system, skew feed correction can be effected while the sheet is transported without being once stopped and therefore, the throughput of the sheet is not reduced. FIG. 13 of the accompanying drawings is a typical view illustrating a method of correcting the skew feed of a sheet transported by the active registration system.
[0006] As the above-described conventional skew feed correction control method, there is an acceleration and deceleration control method or the like as shown in FIG. 13 wherein a transport roller 14 on one side preceding by skew feed is deceleratedly driven (the arrow D in FIG. 13) and at the same time, the accelerated drive of a transporting roller 13 (the arrow A in FIG. 13) on the other side delayed is effected.
[0007] On the other hand, the skew feed direction, the detected skew feed amount (Nb), etc. of an original transported by rollers 13 and 14 are measured by original detecting sensors 15 and 16 . As drive sources for rotatively driving the rollers 13 and 14 , use is usually made of pulse motors 11 and 12 , and the aforementioned detected skew feed amount Nb is measured by counting the time from after one of the original detecting sensors 15 and 16 has detected the original until the other sensor detects the original, by counting clocks driving the pulse motors 11 and 12 .
[0008] Further, the original detecting sensors 15 and 16 are disposed at distances equal from the center of the main scan direction to the right and left and therefore, there is the characteristic that when skew feed control is effected in conformity with the detected skew feed amount Nb calculated from the detection information of these detecting sensors 15 and 16 , the transport of the original in the central portion of the main scan direction of the original does not differ from the ordinary transport thereof, in the case of the acceleration and deceleration control method.
[0009] However, an improvement in the sheet transporting speed has sometimes caused, in addition to the skew feed of the sheet, the deviation of the sheet position in the main scan direction.
[0010] By the conventional active registration system, it has been impossible to detect the deviation of the sheet position in the main scan direction and therefore, to correct the deviation of the sheet position.
SUMMARY OF THE INVENTION
[0011] The present invention has been made in view of the above-noted problem and an object thereof is to provide a sheet transporting apparatus which can efficiently effect the correction of the positional deviation of a sheet in the main scan direction and the correction of the skew feed of the sheet.
[0012] (1) In order to achieve the above object, a sheet transporting apparatus according to the present invention has a pair of sheet transporting members having rotary shafts on the same axis in a direction perpendicular to the transport direction of a sheet and rotatively driven independently of each other to thereby transport the sheet, detecting means provided along a cross direction perpendicular to the sheet transport direction for detecting the transported state of the sheet transported by the sheet transporting members, and control means for drive-controlling the pair of sheet transporting members on the basis of the detection information of the detecting means, and effecting the correction of a sheet position in the cross direction and the correction of the skew feed posture of the sheet relative to the transport direction.
[0013] (2) In the above item (1), the control means may preferably give a transporting speed difference between the pair of transporting members.
[0014] (3) In the above item (1), the detecting means may preferably be a line sensor disposed in parallelism to the cross direction and the size of a detectable area in the cross direction by the line sensor may preferably be larger than the size of at least an area through which the sheet passes when transported in the cross direction.
[0015] (4) In the above item (1), the detecting means may preferably be disposed upstream of the pair of transporting members with respect to the sheet transport direction.
[0016] (5) In the above item (1), the detecting means may preferably be disposed downstream of the pair of transporting members with respect to the sheet transport direction.
[0017] (6) In the above item (1), the control means may preferably effect deviation correction control in the cross direction and skew feed direction of the sheet caused by the pair of transporting members in parallel with each other.
[0018] (7) In the above item (1), the sheet transporting apparatus may preferably have calculating means for calculating the movement direction and the movement amount of the sheet in the cross direction, and the skew feed direction and the skew feed amount of the sheet, relative to a normal transport position, on the basis of the detection information of the detecting means.
[0019] (8) In the above item (7), the calculating means may preferably calculate the skew feed direction and the skew feed amount after the deviation correction control in the cross direction of the sheet to thereby calculate a total skew feed direction and a total skew feed amount, and the control means may preferably effect the deviation correction control in the skew feed direction of the sheet on the basis of the total skew feed direction and the total skew feed amount.
[0020] Other objects and features of the present invention will become apparent from the following description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is a schematic view showing the construction of the essential portions of a first embodiment of the present invention.
[0022] [0022]FIG. 2 is a block diagram showing the control construction of the sheet transporting apparatus of FIG. 1.
[0023] [0023]FIGS. 3A and 3B are typical views illustrating a main scan deviation detecting method and a skew feed detecting method in the sheet transporting apparatus of FIG. 1.
[0024] [0024]FIG. 4 is a flow chart illustrating the control procedure of effecting main scan deviation correction and skew feed correction in the first embodiment of the present invention.
[0025] [0025]FIG. 5 is a schematic view illustrating the construction of the essential portions of a second embodiment of the present invention.
[0026] [0026]FIG. 6 is a block diagram illustrating the control construction of the second embodiment of the present invention.
[0027] [0027]FIGS. 7A and 7B are typical views illustrating a main scan deviation detecting method and a skew feed detecting method in the second embodiment of the present invention.
[0028] [0028]FIG. 8 is a flow chart illustrating the control procedure of effecting main scan deviation correction and skew feed correction in the second embodiment of the present invention.
[0029] [0029]FIG. 9 is a schematic view illustrating the construction of the essential portions of a third embodiment of the present invention.
[0030] [0030]FIG. 10 is a block diagram illustrating the control construction of the third embodiment of the present invention.
[0031] [0031]FIGS. 11A and 11B are typical views illustrating a main scan deviation detecting method and a skew feed detecting method in the third embodiment of the present invention.
[0032] [0032]FIG. 12 is a flow chart illustrating the control procedure of effecting main scan deviation correction and skew feed correction in the third embodiment of the present invention.
[0033] [0033]FIG. 13 is a typical view illustrating a method of correcting the skew feed of a sheet transported by a conventional sheet transporting apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0034] Description will first be made of a first embodiment of a sheet transporting apparatus which achieves the objects of the present invention.
[0035] [0035]FIG. 1 is a schematic view illustrating the construction of the essential portions of the sheet transporting apparatus according to the present embodiment. In FIG. 1, the same members as the members shown in FIG. 13 are given the same reference numerals.
[0036] In FIG. 1, the sheet transporting apparatus according to the present embodiment has transporting rollers 13 and 14 frictionally contacting with a sheet to thereby transport the sheet in a predetermined transport direction, and a sheet detecting line sensor 17 , which is perpendicular to the transport direction of the sheet and disposed at a distance equal from the center of a transport path along which the sheet is normally transported to the right and left in order to measure the deviation amount and deviation direction in a direction perpendicular to the sheet transport direction (hereinafter referred to as the main scan direction), and a skew feed direction and a skew feed amount N. Also, this sheet detecting line sensor 17 is disposed downstream of the transporting rollers 13 and 14 in the transport path of the sheet.
[0037] Also, the transporting rollers 13 and 14 each have a center of rotation on a straight line extending in the main scan direction (cross direction) on the transport path of the sheet, and are disposed in opposed relationship with each other with an interval of a distance “a” therebetween, and are directly connected to pulse motors 11 and 12 , respectively, and are drive-controlled independently of each other.
[0038] The detectable area “d” by the sheet detecting line sensor 17 is wider than at least the widthwise length of the transport path of the sheet.
[0039] [0039]FIG. 2 is a block diagram illustrating the control construction of the sheet transporting apparatus according to the present embodiment. In FIG. 2, a skew feed amount calculating portion 201 calculates the skew feed direction and skew feed amount N of the sheet being transported relative to the normal transport posture thereof on the basis of detection information from the sheet detecting line sensor 17 . A main scan deviation amount calculating portion 203 calculates a main scan deviation direction which is a direction deviating from a normal transport position in the cross direction of the sheet, and a main scan deviation amount X which is a deviation amount in the main scan deviation direction, on the basis of the detection information from the sheet detecting line sensor 17 .
[0040] A correction control portion 202 controls driving pulse numbers individually given to the pulse motors 11 and 12 , and corrects the main scan deviation amount and skew feed amount of the sheet during transport, on the basis of the signals of the skew feed direction and the skew feed amount N transmitted from the skew feed amount calculating portion 201 , and the signals of the main scan deviation direction and the main scan deviation amount X transmitted from the main scan deviation amount calculating portion 203 .
[0041] Each of the skew feed amount calculating portion 201 , the correction control portion 202 and the main scan deviation amount calculating portion 203 may be comprised, for example, of a controller provided with a CPU, a ROM, a RAM etc., and storing therein a program for effecting various kinds of control in accordance with the procedure of a flow chart which will be described later.
[0042] [0042]FIGS. 3A and 3B are typical views illustrating a method of detecting the main scan deviation direction, the main scan direction amount X, the skew feed direction and the skew feed amount N (hereinafter referred to as the transported state) of the sheet in the sheet transporting apparatus according to the present embodiment, and in these figures, the same portions are given the same reference numerals and need not be described.
[0043] For the calculation of the main scan deviation amount X, when first, with one side (the pulse motor 11 side) of the sheet detecting line sensor 17 as the reference, as shown in FIG. 3A, the position at which the sheet detecting line sensor 17 has first detected the sheet is defined as α, and the normal positions in the main scan direction which the sheet should originally pass are defined as “b” and “c” (“b” is the position of the end portion of the sheet on the pulse motor 11 side, and “c” is the position of the end portion of the sheet on the pulse motor 12 side), the main scan deviation amount X can be obtained from
X=c−α (or X=b−α ).
[0044] Next, for the calculation of the skew feed amount N, when after the sheet portion has first been detected by the sheet detecting line sensor 17 , as shown in FIG. 3B, the position at which the detected position of the sheet by the sheet detecting line sensor 17 assumes a minimum value (or a maximum value) is defined as β, the time until the position β is assumed is counted at a constant frequency “f” to thereby measure a detected skew feed count number C.
[0045] Next, a detected skew feed amount Nb detected by the sheet detecting line sensor 17 is calculated from Nb=C×V/f by the use of transporting speed V of the sheet. Then, the skew feed amount N in the transporting roller portion actually used for the correction control portion 202 to control the pulse motors 11 and 12 is calculated from N=Nb×(α−β)/a by the use of the detected skew feed amount Nb detected by the sheet detecting line sensor and the distance between the transporting rollers 13 and 14 .
[0046] The correction control portion 202 then controls the driving pulses of the pulse motors 11 and 12 on the basis of the thus obtained transport state to thereby correct the main scan deviation amount and skew feed amount of the transported sheet.
[0047] A correction control method for the main scan deviation amount and the skew feed amount in the sheet transporting apparatus according to the present embodiment will hereinafter be described with reference to a flow chart shown in FIG. 4.
[0048] In the case of FIGS. 3A and 3B, the sheet is in a skew feed posture rotated leftwardly relative to its normal position and therefore, the corner portion of the sheet which is far from the reference position of the sheet detecting line sensor 17 is first detected and the value thereof becomes a maximum value, but in an opposite skew feed posture, the corner portion of the sheet which is near is first detected and therefore the value thereof becomes a minimum value.
[0049] In FIG. 4, the main scan deviation correction amount obtained on the basis of the main scan deviation amount X is represented by Xo, the main scan deviation allowable value determining the allowable range of the main scan deviation amount X is represented by Xm, and the skew feed allowable value determining the allowable range of the skew feed amount N is represented by Nm.
[0050] When at a step 1 , the sheet detecting line sensor 17 detects the sheet, the main scan deviation amount calculating portion 203 calculates the main scan deviation direction and the main scan deviation amount X.
[0051] When at a step 2 , the detected position of the sheet by the sheet detecting line sensor 17 has assumed a minimum value (or a maximum value), the skew feed amount calculating portion 201 calculates the skew feed direction and the skew feed amount N.
[0052] At a step 3 , the correction control portion 202 judges whether the main scan deviation amount X is within a range of −Xm≦X≦Xm, and when it is judged to be within this allowable range, at a step 8 , the correction control portion 202 judges whether the skew feed amount N is within an allowable range of −Nm≦N≦Nm, and when it is judged to be within the allowable range processing is ended.
[0053] On the other hand, when at the step 3 , the main scan deviation amount X is judged to be not within the allowable range of −Xm≦X≦Xm, at a step 4 , the correction of the main scan deviation amount (hereinafter referred to as the main scan deviation correction) is effected for a predetermined period by the correction control portion 202 .
[0054] Then, at a step 5 , a total skew feed amount is calculated from the skew feed amount caused by the main scan deviation correction and the skew feed amount calculated by the skew feed amount calculating portion 201 , and at a step 6 , the correction of the total skew feed amount (hereinafter referred to as the skew feed correction) is effected by the correction control portion 202 .
[0055] Subsequently, at a step 7 , the correction control portion 202 judges whether the main scan deviation correction amount Xo is within an allowable range of X−Xm≦Xo≦X+Xm, and when it is judged to be within the allowable range, processing is ended.
[0056] When at the step 7 , the main scan deviation correction amount correction Xo is judged to be not within the allowable range of X−Xm≦Xo≦X+Xm, return is made to the step 4 , where the main scan deviation correction is again effected for a predetermined period by the correction control portion 202 , whereafter similar steps are executed.
[0057] When at a step 8 , the skew feed amount N is judged to be not within the allowable range of −Nm≦N≦Nm, at a step 9 , the skew feed correction is effected by the correction control portion 202 by an amount corresponding to the skew feed amount N calculated by the skew feed amount calculated portion 201 , and processing is ended.
[0058] As described above, according to the present embodiment, the pulse motors 11 and 12 are drive-controlled in conformity with the transported state of the sheet calculated on the basis of the detection information of the transported sheet to thereby effect the widthwise deviation correction and the skew feed correction, whereby the sheet can be corrected into its normal transported state and be transported.
Second Embodiment
[0059] A second embodiment will now be described. While in the above-described first embodiment, description has been made of the correction control in which the main scan deviation correction and the skew feed correction are repeated and effected little by little on the basis of the deviation direction in the main scan direction, the deviation amount in the main scan direction, the skew feed direction and the skew feed amount calculated by detecting the sheet transported sheet by the sheet detecting line sensor as the sheet detecting means downstream of the transporting rollers as the driving means for transporting the sheet, in the present embodiment, the sheet detecting line sensor 17 as the sheet detecting means is disposed upstream of the transporting rollers as the sheet driving means with respect to the transport direction, and design is made so as to effect the main scan deviation correction and the skew feed correction by transporting rollers downstream of the sheet detecting line sensor 17 with respect to the transport direction, i.e., transporting rollers discrete from the transporting rollers which have caused skew feed, on the basis of the deviation direction in the main scan direction, the deviation amount in the main scan direction, the skew feed direction and the skew feed amount calculated by detecting the sheet.
[0060] [0060]FIG. 5 is a schematic view illustrating the construction of the essential portions of a sheet transporting apparatus according to the present embodiment, and in FIG. 5, the above-described portions are given the same reference numerals and need not be described. The sheet detecting line sensor 17 in the present embodiment is disposed upstream of the transporting rollers 13 and 14 for effecting the main scan deviation correction and the skew feed correction on the transport path of the sheet with respect to the transport direction, and effects the detection of the transported state of the sheet transported by transporting means, not shown.
[0061] [0061]FIG. 6 is a block diagram illustrating the control construction of the sheet transporting apparatus according to the present embodiment.
[0062] In FIG. 6, the reference numeral 601 designates a skew feed amount calculating portion which calculates the skew feed direction and skew feed amount N of the sheet on the basis of detection information from the sheet detecting line sensor 17 . The reference numeral 603 denotes a main scan deviation amount calculating portion which calculates the main scan deviation direction and main scan deviation amount X of the sheet on the basis of the detection information from the sheet detecting line sensor 17 . A correction control portion 602 controls driving pulse numbers given to the pulse motors 11 and 12 on the basis of the signals of the skew feed direction and the skew feed amount N transmitted from the skew feed amount calculating portion 601 , and the main scan deviation direction and the main scan deviation amount X transmitted from the main scan deviation amount calculating portion 603 , and corrects the main scan deviation amount and skew feed amount of the transported sheet.
[0063] Each of the skew feed amount calculating portion 601 , the correction control portion 602 and the main scan deviation amount calculating portion 603 may be comprised, for example, of a controller provided with a CPU, a ROM and a RAM, and may be controlled in accordance with the procedure of a flow chart which will be described later.
[0064] [0064]FIGS. 7A and 7B are typical views illustrating a method of detecting the transported state of the sheet in the sheet transporting apparatus according to the present embodiment, and in these figures, the same members as the above-described members are given the same reference numerals and need not be described.
[0065] For the calculation of the main scan deviation amount X, first, when the position at which the sheet has first been detected by the sheet detecting line sensor 17 is defined as α, and the normal widthwise positions which the sheet should originally passes at the sheet detecting line sensor 17 are defined as “b” and “c” (“b” is the position of the end portion of the sheet on the pulse motor 11 side, and “c” is the position of the end portion of the sheet on the pulse motor 12 side), X is calculated from
X=c−α (or X=b−α ).
[0066] For the calculation of the skew feed amount N, a position β at which the detected position of the sheet by the sheet detecting line sensor 17 assumes a minimum value (or a maximum value) and the time until the sheet becomes undetected by the sheet detecting line sensor 17 are counted at a constant frequency “f” to thereby measure a detected skew feed count number C. Also, the position at which the sheet has been detected lastly by the sheet detecting line sensor 17 is defined as Υ.
[0067] Next, the detected skew feed amount Nb in the sheet detecting line sensor 17 itself is calculated from Nb=C×V/f by the use of the transporting speed of the sheet. The skew feed amount N in the transporting roller portion actually used for the correction control portion 602 to control the pulse motors 11 and 12 is calculated from N=Nb×(Υ−β)/a by the use of the detected skew feed amount Nb detected by the sheet detecting line sensor and the distance “a” between the transporting rollers.
[0068] The correction control portion 602 controls driving pulse numbers given to the pulse motors 11 and 12 on the basis of the signals of the thus obtained skew feed direction and skew feed amount N, and the main scan deviation direction and the main scan deviation amount X, and corrects the main scan deviation amount and skew feed amount of the transported sheet.
[0069] A method of correcting the main scan deviation amount and skew feed amount in the sheet transporting apparatus according to the present embodiment will hereinafter be described with reference to a flow chart shown in FIG. 8.
[0070] [0070]FIG. 8 is a flow chart illustrating the procedure of correcting the main scan deviation amount and skew feed amount in the sheet transporting apparatus according to the present embodiment.
[0071] A main scan deviation allowable value determining the allowable range of the main scan deviation amount X is represented by Xm, and a skew feed allowable value determining the allowable range of the skew feed amount N is represented by Nm.
[0072] At a step 11 , when the sheet detecting line sensor 17 detects the sheet, the main scan deviation amount calculating portion 603 calculates the main scan deviation direction and the main scan deviation amount X.
[0073] At a step 12 , the correction control portion 602 judges whether the main scan deviation amount X is within an allowable range of −Xm≦X≦Xm, and when it is judged to be within the allowable range, the main scan deviation correction is not effected, but the sheet is intactly transported.
[0074] Next, when at a step 14 , the detected position of the sheet by the sheet detecting line sensor 17 assumes a minimum value (or a maximum value) and thereafter the sheet becomes undetected by the sheet detecting line sensor 17 , the skew feed amount calculating portion 601 calculates the skew feed direction and the skew feed amount N. Subsequently, at a step 15 , the correction control portion 602 judges whether the skew feed amount N is within an allowable range of −Nm≦N≦Nm, and when it is judged to be within the allowable range, processing is ended.
[0075] On the other hand, when at the step 12 , the main scan deviation amount X is judged to be not within the allowable range of −Xm≦X ≦Xm, at a step 13 , the main scan deviation correction is effected by the correction control portion 602 by an amount corresponding to the main scan deviation amount X calculated by the main scan deviation amount calculating portion 603 , whereafter the sheet is transported.
[0076] When at the step 15 , the skew feed amount N is judged to be not within the range −Nm≦N≦Nm, at a step 16 , the skew feed correction is effected by the correction control portion 602 by an amount corresponding to the skew feed amount N calculated by the skew feed amount calculating portion 601 , and processing is ended.
[0077] As described above, according to the present embodiment, the sheet detecting line sensor as the detecting means is disposed upstream of the transporting rollers 13 and 14 with respect to the transport direction, and the pulse motors 11 and 12 are drive-controlled in conformity with the transported plate obtained on the basis of the detection information of the transported sheet to thereby effect the widthwise deviation correction, whereafter the skew feed correction is effected, whereby the sheet can be transported with the main scan deviation and skew feed thereof corrected.
Third Embodiment
[0078] A third embodiment will now be described. While in the above-described first embodiment, description has been made of the correction control in which the main scan deviation correction and the skew feed correction are repeated and effected little by little on the basis of the deviation direction of the main scan direction, the deviation amount of the main scan direction, the skew feed direction and the skew feed amount calculated by detecting the transported sheet by the sheet detecting line sensor as the sheet detecting means downstream of the transporting rollers as the driving means for transporting the sheet, the present embodiment is designed such that the main scan deviation correction is effected on the basis of the deviation direction of the main scan direction, the deviation amount of the main scan direction, the skew feed direction and the skew feed amount calculated by detecting the transported sheet, whereafter a total skew feed amount is calculated from the aforementioned calculated skew feed amount and the skew feed amount caused by the main scan deviation correction to thereby effect the skew feed correction.
[0079] In the present embodiment, the main scan deviation correction is effected on the basis of the transported state obtained by detecting the transported sheet, whereafter the total skew feed amount is calculated from the aforementioned calculated skew feed amount and the skew feed amount caused by the main scan deviation correction to thereby effect the skew feed correction.
[0080] [0080]FIG. 9 illustrates the construction of a sheet transporting apparatus according to the present embodiment, and in FIG. 9, the same members as the above-described members are give the same reference numerals, and need not be described. FIG. 10 is a block diagram illustrating the control construction of the sheet transporting apparatus according to the present embodiment.
[0081] In FIG. 10, the reference numeral 17 designates a sheet detecting line sensor which effects the detection of the transported state of the sheet. The reference numeral 1001 denotes a skew feed amount calculating portion which calculates the skew feed direction and skew feed amount N of the sheet on the basis of detection information from the sheet detecting line sensor 17 . The reference numeral 1003 designates a main scan deviation amount calculating portion which calculates the main scan deviation direction and main scan deviation amount X of the sheet on the basis of the detection information from the sheet detecting line sensor 17 .
[0082] The reference numeral 1004 denotes a total skew feed amount calculating portion which calculates the skew feed direction and skew feed amount M of the sheet after the main scan deviation correction based on the main scan deviation direction and the main scan deviation amount X transmitted from the main scan deviation amount calculating portion 1003 has been effected, and calculates a total skew feed direction as an overall skew feed direction and a total skew feed amount L as an overall skew feed amount from the skew feed direction and the skew feed amount N transmitted from the skew feed amount calculating portion 1001 and the skew feed direction and the skew feed amount M caused by the main scan deviation correction.
[0083] A correction control portion 1002 increases or decreases driving pulse numbers given to the right and left pulse motors 11 and 12 , on the basis of the total skew feed direction and the total skew feed amount L transmitted from the total skew feed amount calculating portion 1004 , and the main scan deviation direction and the main scan deviation amount X transmitted from the main scan deviation amount calculating portion 1003 , and corrects the main scan deviation amount and skew feed amount of the transported sheet.
[0084] While in the present embodiment, the total skew feed amount calculating portion 1004 is of a construction discrete from the correction control portion 1002 , this is not restrictive, but for example, the total skew feed amount calculating portion 1004 may be of a construction included in the correction control portion 1002 .
[0085] Each of the skew feed amount calculating portion 1001 , the correction control portion 1002 , the main scan deviation amount calculating portion 1003 and the total skew feed amount calculating portion 1004 may be comprised, for example, of a controller provided with a CPU, a ROM, a RAM, etc., and may be of a construction which controls in accordance with the procedure of a flow chart which will be described later.
[0086] [0086]FIGS. 11A and 11B are typical views illustrating a method of detecting a sheet position in the sheet transporting apparatus shown in FIG. 9, and in these figures, the same members as those in FIG. 9 are given the same reference numerals.
[0087] For the calculation of the main scan deviation amount X, first, when the position at which the sheet has been first detected by the sheet detecting line sensor 17 is defined as α, and the widthwise positions which the sheet should originally pass are defined as “b” and “c” (“b” is the pulse motor 11 side, and “c” is the pulse motor 12 side), X is calculated from X=c−α(or X=b−α).
[0088] Next, for the calculation of the skew feed amount N, the time from after the sheet position has been first detected by the sheet detecting line sensor 17 until the detected position of the sheet by the sheet detecting line sensor 17 assumes a minimum value (or a maximum value) is counted at a constant frequency f to thereby measure a skew feed count number C. Next the detected skew feed amount Nb in the sheet detecting line sensor 17 itself is calculated from Nb=C×V/f by the use of the transporting speed V of the sheet. The skew feed amount N in the transporting roller portion actually used for the correction control portion 1002 to control the pulse motors 11 and 12 is calculated from N=Nb×b/a by the use of the detected skew feed amount Nb detected by the sheet detecting line sensor 17 , the distance “a” between the transporting rollers and the distance “b” from the sheet detecting line sensor.
[0089] A method of correcting the main scan deviation amount and the skew feed amount in the sheet transporting apparatus according to the present embodiment will hereinafter be described with reference to a flow chart shown in FIG. 12.
[0090] [0090]FIG. 12 is a flow chart illustrating the procedure of the method of correcting the main scan deviation amount and the skew feed amount in the sheet transporting apparatus according to the present embodiment.
[0091] In FIG. 12, a main scan deviation allowable value determining the allowable range of the main scan deviation amount X is represented by Xm, and a skew feed allowable value determining the allowable range of the skew feed amount N is represented by Nm.
[0092] When at a step 21 , the sheet detecting line sensor 17 detects the sheet, the main deviation amount calculating portion 1003 calculates the main scan deviation direction and the main scan deviation amount X.
[0093] When at a step 22 , the detected position of the sheet by the sheet detecting line sensor 17 assumes a minimum value (or a maximum value), the skew feed amount calculating portion 1001 calculates the skew feed direction and the skew feed amount N.
[0094] At a step 23 , the correction control portion 1002 judges whether the main scan deviation amount X is within an allowable range of −Xm≦X≦Xm, and when it is judged to be within the allowable range, at a step 29 , the correction control portion 1002 judges whether the skew feed amount N is within an allowable range of −Nm≦N≦Nm, and when it is judged to be within the allowable range, processing is ended.
[0095] When at the step 23 , the main scan deviation amount X is judged to be not within the allowable range of −Xm≦X≦Xm, at a step 24 , main scan deviation correction is effected by the correction control portion 1002 .
[0096] Next, at a step 25 , the skew feed direction and the skew feed amount M caused by the main scan deviation correction are calculated by the total skew feed amount calculating portion 1004 , and subsequently at a step 26 , the total skew feed direction and the total skew feed amount L are calculated by the total skew feed amount calculating portion 1004 with the skew feed direction and the skew feed amount N obtained from the skew feed amount calculating portion 1001 being taken into account.
[0097] Next, at a step 27 , the correction control portion 1002 judges whether the total skew feed amount L is within an allowable range of −Nm≦L≦Nm, and when it is judged to be within the allowable range, processing is ended.
[0098] When at the step 27 , the total skew feed amount L is judged to be not within the allowable range of −Nm≦L≦Nm, at a step 28 , skew feed correction is effected by the correction control portion 1002 by an amount corresponding to the total skew feed amount L calculated by the total skew feed amount calculating portion 1004 .
[0099] When at a step 29 , the skew feed amount N is judged to be not within an allowable range of −Nm≦N≦Nm, at a step 30 , skew feed correction is effected by the correction control portion 1002 by an amount corresponding to the skew feed amount N calculated by the skew feed amount calculating portion 1001 , and processing is ended.
[0100] Thus, main scan deviation correction is effected on the basis of the widthwise deviation direction, the widthwise deviation amount X, the skew feed direction and the skew feed amount N calculated on the basis of the detection of the transported sheet, whereafter the pulse motors 11 and 12 are drive-controlled in conformity with the total skew feed amount L from the above-calculated skew feed amount N and the skew feed amount M caused by the main scan deviation correction to thereby effect the correction of the main scan deviation amount and the correction of the skew feed amount at a time, whereby the sheet can be transported in a normal transported state.
[0101] It is also possible to supply a storage medium having recorded therein a program code of software for realizing the operation of the sheet transporting apparatus according to each of the above-described embodiment to a system or an apparatus having a computer or the like, and read out and execute the program code stored in this storage medium by the computer (or the CPU or MPU) of the system or the apparatus. In this case, the above-described system is not restricted to one having a single apparatus, but may be one having a plurality of apparatuses.
[0102] The sheet transporting apparatus according to each of the above-described embodiments can also be used as sheet transporting means in an image reading apparatus such as a scanner, or an image forming apparatus such as a printer or a facsimile. | 50 An image forming apparatus having a pair of sheet transporting members having rotary shafts on the same axis in a direction perpendicular to the transport direction of a sheet, and rotatively driven independently of each other to thereby transport the sheet, a detector provided along a cross direction perpendicular to the transport direction of the sheet for detecting the transported state of the sheet transported by the sheet transporting members, and a controller for drive-controlling the pair of sheet transporting members on the basis of the detection information of the detector, and effecting the correction of a sheet position in the cross direction and the correction of the skew feed posture of the sheet relative to the transport direction. | 6 |
BACKGROUND OF THE INVENTION
In the fabrication of sanitary pads such as sanitary napkins, hospital pads, disposable diapers and the like, a certain percentage of the pads will be defective and are discarded. While the filler material utilized in such pads, typically cellulose fluff, constitutes high quality reusable material, other component parts of the pad such as the film backing and adhesive tape fasteners are not in condition for reuse and at best contaminate the reusable fluff. Heretofore, any attempt to reuse the fluff or filler material has involved returning the entire pad, including the undesirable film backing and adhesive tape fastener components thereof to a recovery unit which tears the pad apart and returns all components thereof in comminuted form to the pad manufacturing machine. This results in a small percentage of film and adhesive tape particles in the filler for the next batch of pads and contaminates and reduces the quality of the filler material below that of virgin filler.
SUMMARY OF THE INVENTION
In accordance with the present invention, the undesirable components of otherwise waste pads, typically the backing film and adhesive tape fasteners, are not salvaged but are separated from the pad and are discarded. Only the filler material is recovered for salvage, thus maintaining high quality in the filler supply.
In accordance with the present invention, the waste pad is laid out flat and the cover sheet is cut open to expose the filler. The filler is then sucked from the pad, together with any fragments of the cover sheet. This useful material is returned to the pad fabricating machine and constitutes high quality filler material. The plastic backing and adhesive fastening tapes are collected and discharged to waste and do not return to the pad fabricating machine.
Other objects, features and advantages of the invention will appear from the disclosure hereof.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of apparatus embodying the present invention.
FIG. 2 is a side elevation of the apparatus of FIG. 1.
FIG. 3 is a schematic view similar to FIG. 1, but illustrating method steps.
FIG. 4 is a fragmentary cross section taken along the line 4--4 of FIG. 1.
FIG. 5 is an enlarged fragmentary cross section taken along the line 5--5 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. The scope of the invention is defined in the claims appended hereto.
In the disclosed embodiment, the pad 10 to be salvaged comprises a disposable diaper typically having a non-woven fabric cover sheet 11, a plastic film backing sheet 12 and an absorbent filler material 13 which typically comprises crepe wadding or cellulose fluff. Adhesive tape fasteners 14 may be applied at certain corners of the plastic film backing 12.
The pad fabricating machine is not shown in the drawings, but in typical installations an inspector will detect a defective pad 10 and will remove it from the pad fabricating machine and lay it out flat on a movable tray 15 which is mounted on slideways 16 on which the tray is movable in the direction of arrow 17.
As best shown in FIG. 4, tray 15 is desirably provided with a series of perforations 20 through which pad 10 is exposed to the vacuum in a vacuum box 21. Vacuum box 21 is beyond the initial position of the tray 15 as it is shown in FIG. 1 and is beneath a first pad cover slitting mechanism 22. Slitter 22 comprises a set of ganged knife-edged wheels 23 which are mounted on a common shaft 24 driven by motor 25.
As tray 15 is advanced in the direction of arrow 17 beneath the first slitter 22, the subatmospheric pressure in the vacuum box 21 will hold the pad 10 securely against the tray 15, while the ganged knife-edged slitting wheels 23 will produce a series of longitudinal slits 26 (FIG. 3) in the pad cover 11.
After the longitudinal slits 26 are produced in the cover sheet 11 of the pad 10, the pad 10 is advanced further to its position indicated at 30 in FIG. 1 and FIG. 3, where it overlies a perforated belt 31 having perforations 42 traveling over a vacuum box 32. The ends of the perforated belt 31 are supported on end rolls 33.
The top run of belt 31 travels in the direction of arrow 34 (FIG. 1), transverse to the direction of arrow 17, and the partially slit pad 10 is transported thereon in said transverse direction to a second slitting mechanism 35. Slitting mechanism 35 also desirably comprises ganged knife-edged wheels 36 mounted within a vacuum hood 37 which has a discharge duct 40. Wheels 36 are powered by motor 38. The second slitter 35 will produce transverse slits 41 in the pad cover 11 to thoroughly open up the cover sheet 11 for vacuum removal of the fluff or filler material 13 from the pad into hood 37 and through the duct 40 to a recovery unit, now shown. As the suction in hood 37 is removing the filler material 13 from the pad, the plastic backing sheet 12 and adhesive tape fasteners 14 will be securely held by vacuum against the traveling perforated belt 31. Moreover, to securely hold the film backing 12 against dislocation, the pad 10 beneath hood 37 is held down at its side margins by traveling overhead belts 43 which are guided over end pulleys 44 to clamp the plastic backing sheet 12 against the perforated belt 31.
To assist the vacuum removal of the filler, hood 37 is also provided with a rotating brush 45 which rotates in the direction of arrow 46 in FIG. 5 and is mounted on a shaft 47. As indicated in FIG. 5, the brush 45 mechanically sweeps the filler material 13 from the pad 10 in the direction of arrows 50 into the air stream exhausted from hood 37 through duct 40.
The suction and sweeping apparatus will remove not only the filler material 13, but also any completely severed strips or portions of the cover sheet 11. Both of these components of the pad will be conveyed through duct 40 back to the filler supply for the pad fabrication machine. Both of these components constitute high quality filler material.
All that is left on the belt 31 is the plastic film backing 12, the adhesive tape fasteners 14 and any small fragments of filler material 13 and particles of cover sheet 11 which are not swept and sucked from the pad through the hood 37. The film backing sheet 12 and adhesive tape fasteners 14 then continue on the belt 31 to a discharge chute 51 where they are discharged to waste. An overhead belt 52 driven by motor 53 cooperates with the perforated belt 31 to ensure proper discharge of the waste to the chute 51. | Method and apparatus of recovering filler from a sanitary pad. The pad typically has a film backing and a cover sheet and filler therebetween. Such a pad is laid out flat and advanced through a cutter which opens up the cover to expose the filler. The filler is sucked from the pad for salvage and the film backing is discarded. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a non-provisional U.S. application which is based on and claims priority under 35 U.S.C. 119(e) from provisional Application Ser. No. 60/988,302, filed on Nov. 15, 2007.
BACKGROUND
[0002] 1. Technical Field
[0003] This disclosure relates to odor reduction or elimination from air through the use of vapor phase hydrogen peroxide in combination with a media coated with a transition metal element or compound. Odor reduction or elimination is accomplished by the synergistic introduction of vapor phase hydrogen peroxide (VPHP) into malodorous air and allowing the malodorant and VPHP to engage a catalyst, where the catalyst comprises at least one transition metal element or compound.
[0004] 2. Description of Related Art
[0005] The issue of malodors, and their potential adverse effects on health and quality of indoor life, has been a concern for centuries. While malodors are sometimes an indicator of danger or disease, they are typically little more than an unpleasant experience that negatively affect ambiance. Thus, for both nuisance and health reasons, methods have been sought to eliminate or substantially alleviate malodors wherever they are encountered, especially from indoor environments.
[0006] Many devices and techniques have evolved to treat malodors. Such methods or techniques have included masking odors with perfumes, fragrances or incense, displacing malodorous air with fans or blowers, absorbing malodors with activated carbon or other materials, and removing malodors from air using electrostatic precipitators. These methods and devices, though somewhat effective in lessening the impact of malodors, generally do not actually eliminate the malodorous substances themselves from the indoor environment.
[0007] While displacing malodorous indoor air with fans or blowers, and replacing it with fresh outdoor air may actually eliminate malodors from an indoor environment, such an approach to indoor malodor abatement is economically impractical when said indoor air is temperature and/or humidity controlled. Further, many indoor spaces such as high-rise apartments and high-rise offices do not have direct access to fresh outdoor air.
[0008] In the case of activated carbon, malodorous materials are not changed and may in fact be desorbed as a result of temperature fluctuations or interior carbon particle saturation—thus rendering this method less than optimally effective. The mechanism involved entails three separate (physical) processes which leave the malodorous substances intact: condensation, Van der Waals attraction and diffusion to the carbon particle interior.
[0009] Similarly, electrostatic precipitation consists essentially of a flocculation and subsequent collection of charged dust particles. Odor removal with this technique requires adsorption of malodors onto the targeted dust particles. Like techniques using activated carbon, this approach is clearly limited by the volatility and adsorbing propensity of the molecules involved. In any case, the odoriferous materials are not converted to less offensive compounds.
[0010] Perfume masking techniques (fragranced sprays, incenses, etc.) also leave the offending substances unchanged, which is less desirable than destroying, altering or deactivating the malodorous compounds. However, other approaches utilize chemical conversion to render malodorants innocuous. Examples of chemical conversion techniques include the use of promoters such as water-soluble ethylene oxide or propylene oxide derivatives, or mixtures of thereof. Other examples include molecules with one or more functional groups acting as a Lewis acid, Lewis base, oxidizing agent, reducing agent, or other functional group that will chemically neutralize the malodorant particles.
[0011] Finally, other techniques utilize materials that remove the malodorants from the gas phase and therefore reduce their partial pressure in the ambient air. For example, triethylene glycol, film forming polymers and cyclodextrins have been used to reduce the partial pressure of malodorants by physically removing malodor molecules from the ambient air without chemically neutralizing or altering them. In the case of triethylene glycol, the malodor molecules are partitioned into globules or droplets; in the case of film forming polymers, the malodors are “blanketed” or trapped; in the case of cyclodextrins, the malodors are trapped in the cage-like structure of cyclodextrins. In these scenarios, the malodors molecules are displaced rather than being chemically transformed into one or more less malodorous substances.
[0012] Hydrogen peroxide, an inexpensive and somewhat reactive oxidant, can also be used for malodor elimination or reduction by oxidizing malodorant molecules. However, current uses of hydrogen peroxide are limited to the use of aqueous solutions. For example, aqueous hydrogen peroxide solutions are used to remove food and smoke odors from the restaurant broiling grill emissions, in part through scrubbing of the grill exhaust gas stream through an aqueous peroxide solution. To be effective, the food must be cooked over thin, high temperature ceramic briquettes to enhance incineration of potential malodors, as well as scrubbing the grill gas stream with an aqueous hydrogen peroxide solution, followed by mixing the treated gas with ambient air prior to discharge to the atmosphere. Obviously, these systems are complex and costly and are not suitable for use by general consumers desiring to treat the air in an enclosed space.
[0013] Malodorous air may also be washed with an aqueous solution containing both hydrogen peroxide and ozone. For example, deodorization processes are known which generate and discharge ozone in combination with an atomized hydrogen peroxide solution. A reaction between ozone and atomized hydrogen peroxide generates a hydroxyl radical which is said to decompose various malodorous substances present in an indoor environment. However, the ozone generating requirement of these apparatuses makes them costly and potentially hazardous.
[0014] In a sewage treatment process, odor abatement is achieved by contacting hydrophobic components of an odor-containing gas plume condensate with odor-trapping core particles containing precipitates resulting from reaction ferrous ion, tannic acid, and hydrogen peroxide. Other processes utilize aqueous deodorant compositions containing hydrogen peroxide and nitrate ion or hydrogen peroxide, nitrate ion, and a transition metal salt. The aqueous deodorant compositions are typically mixed directly with the waste stream. Sulfide odors can be reduced or eliminated from the vapor spaces of waste handling and treatment systems by injecting a fine spray, mist or fog of an aqueous alkaline hydrogen peroxide solution into air spaces within sewage-containing system handling or treatment equipment.
[0015] Aqueous alkaline phosphate-containing hydrogen peroxide compositions for various odor elimination and disinfection uses are also known. The aqueous compositions are introduced onto surfaces and into air handling ducts by the application of a spray or mist of the aqueous alkaline peroxide solutions. The alkaline phosphate salts are said to enhance the oxidizing power of the peroxide and also to function as a peroxide stabilizer.
[0016] One catalytic process for removal of malodors from industrial gas streams includes scrubbing the gas stream through a fixed bed scrubber fitted with a solid packing bed containing a transition metal catalyst and hydrogen peroxide-containing liquor. While this technique is suitable for industrial systems, it is not applicable to home or office use.
[0017] Therefore, a need exists for malodor treatment compositions and methods which are straightforward and inexpensive to manufacture and which provide effective reduction or elimination of malodors in indoor air spaces and that can be safely used by the consuming public.
SUMMARY OF THE DISCLOSURE
[0018] In satisfaction of the aforenoted needs, an improved airborne odor elimination reduction method is disclosed that includes entraining vapor phase hydrogen peroxide (VPHP) in malodorous air and engaging the VPHP-containing malodorous air with a media comprising at least one transition metal element or compound. The media may be provided in a variety of forms, such as, but not limited to powdered materials, granular materials, filter-type structures, pad-type structures, meshes, screens, grids or any solid form capable of being supported for engaging malodorous air. The media may be porous, non-porous, permeable, or non-permeable structures, depending upon the particular product or application. The media structure may be made in whole or in part from the transition metal element or compound (e.g., powders, granular materials, solid structures comprising the transition metal element or compound); the media structure may be at least partially coated with the transition metal element or compound (e.g., filters, meshes, plates, grids, etc.). The term “media” as used herein refers to a solid structure used to provide a contact interface for the transition metal element or compound, VPHP and malodorous materials in the air.
[0019] In a refinement, the media may be a media capable of being coated, such as a woven or nonwoven filter element. The VPHP-containing malodorous air does not have to pass through the media but merely needs to engage the media so that the transition metal element or compound can catalyze the reaction between the malodorous compound and the VPHP.
[0020] Sources of the VPHP include aqueous and solid compositions disclosed in commonly assigned U.S. Patent Application Publication No. 2006/0280665, which is incorporated herein by reference. Preferably, the compositions are pH neutral to mildly acidic compositions and deliver VPHP to surrounding air by passive evaporation from a liquid or sublimation from a solid. The term passive evaporation refers to a process by which hydrogen peroxide is slowly released into the vapor phase by evaporation directly from a bulk liquid composition. This excludes processes whereby the liquid compositions are physically dispersed into the air as bulk liquid or droplets using mechanical means such as spraying, atomizing, fogging, or misting via manually operated or powered devices. The transmission of molecular hydrogen peroxide from a solid peroxohydrate compound directly to the vapor state will be described herein as a sublimination process. Preferably, the VPHP source is a solid composition as outlined in US2006/0280665, but embodiments with a liquid source of VPHP are envisioned.
[0021] In an enclosed space, the VPHP and malodorous compounds can engage the media with sufficient regularity without the need for a blower, fan or air movement mechanism. Such passive embodiments provide excellent malodor treatment in enclosed spaces of various sizes. In an active embodiment, the VPHP is entrained in a stream of the malodorous air simply by exposing at least one of the VPHP-emitting compositions to the malodorous air. Various types of fans and blowers may be utilized as described below.
[0022] In one refinement, VPHP is provided by a peroxohydrate compound selected from the group consisting of urea peroxohydrate, sodium sulfate peroxohydrate, a peroxohydrate of poly(vinylpyrrolidone) polymer and mixtures thereof. A refinement of the current invention employs a device wherein the peroxohydrate compound is provided as a powder, granule, compressed tablet or solid other form, and packaged in an air-permeable container which permits the transmission of VPHP. Malodorous air comes into contact with the device, combining with VPHP, followed by engaging the combination of the malodorous air and VPHP with the media that comprises at least one transition metal element or compound.
[0023] The media used is preferably a porous and/or permeable filter-type media coated with at least one transition metal element or compound. The VPHP-containing malodorous air flows across and/or through the media so as to engage the transition metal element or compound. The transition metal compound may be titanium dioxide (TiO 2 ) or hydrates thereof. Certain transition metal compounds, most notably certain forms of titanium dioxide, have been employed in methods that eliminate malodors through a photocatalytic process using ultraviolet (UV) light. While the disclosed methods employ transition metal compounds to chemically transform/destroy malodors, no UV or other light source is required. The inventors have surprisingly found that the transition metal compound(s) satisfactorily catalyze the chemical transformation/destruction of the malodors by the VPHP entrained in the malodorous air in the absence of UV light, thereby safely and effectively reducing or eliminated the malodors, without resorting to the potentially hazardous use of UV light. Further, the working elements of the disclosed apparatus may be housed in an opaque housing, non-transparent to UV or visible light, having a wavelength from about 200 to about 800 nm. While certain transition metal compounds or hydrogen peroxide alone may individually have the ability to eliminate malodors, the disclosed combination of using at least one transition metal element or compound with VPHP is positively synergistic, providing faster and more effective malodor elimination.
[0024] In a refinement, one disclosed method for reducing malodors from an air stream, comprises; providing vapor phase hydrogen peroxide across and/or through a media that is disposed in an area with malodorous compounds in the ambient air, wherein at least a portion of the exterior surface of the media comprises at least one transition metal element or compound.
[0025] In a refinement, the transition metal(s) are selected from the group consisting of titanium, vanadium, manganese, iron, cobalt, molybdenum, tungsten, nickel, silver, copper and zinc. Preferably, the transition metal(s) are selected from the group consisting of titanium, vanadium, manganese, iron, copper, molybdenum, tungsten and zinc for reasons of low-cost, low toxicity and minimal environmental impact.
[0026] In another refinement, the transition metal compounds(s) are selected from the group consisting of one or more titanium-containing compounds.
[0027] In another refinement, the transition metal compound is selected from the group consisting of titanium dioxide hydrates, and mixtures thereof.
[0028] In another refinement, the transition metal compound-containing coating on the media also contains one or more catalyst promoter compounds that comprise a salt comprising a non-transition metal cation and an anion selected from the group consisting oxide, hydroxide, halide, carbonate, borate, phosphate, sulfate, nitrate, silicate, aluminate, borate aluminate, carboxylate, stannate, and bismuthate.
[0029] In another refinement, the vapor phase hydrogen peroxide is provided through passive evaporation of a pH neutral to mildly acidic liquid aqueous composition containing hydrogen peroxide.
[0030] In another refinement, the vapor phase hydrogen peroxide is provided through sublimation of hydrogen peroxide from a solid composition containing a hydrogen peroxide complex. In another refinement, the vapor phase hydrogen peroxide is provided by sublimation of hydrogen peroxide from a solid composition including at least one pH neutral to slightly acidic peroxohydrate compound. In still another refinement, the solid composition comprises from about 0.1 wt % to about 50 wt % hydrogen peroxide. Preferably, the solid composition is a powder, granule, compressed tablet or crystalline solid form. Further, the solid composition is preferably contained within a porous (gas permeable) container, such as a porous, replaceable pouch. Preferably, the solid composition is one of the peroxohydrate compositions set forth in US2006/0280665.
[0031] In another refinement, the solid composition further comprises one or more of the following: fragrances, colorants, surfactants, solvents, binders, processing agents and hydrogen peroxide-stabilizing agents.
[0032] In a refinement, one or more color change indicators are provided for alerting the user when the device is functional and/or activated and/or when the VPHP supply has become depleted. Specifically, in one refinement, the transition metal compound changes color in the presence of VPHP to indicate to the user that the device is functional. The user may also be alerted that VPHP is not present in sufficient amounts when a second color change occurs, thus the VPHP supply needs to be replenished. Using titanium dioxide as an example, the color change changes from white to yellow in the presence of VPHP, and will revert back to white when the supply of VPHP is exhausted.
[0033] In a refinement, a product may be provided in the form of a non-woven sachet that encloses a solid composition that releases VPHP. The presence of the VPHP causes the catalyst coating of a non-woven to undergo a distinct color change. When the color fades, the consumer will know to either replenish the VPHP source within the sachet or purchase a new product.
[0034] Various apparatuses are disclosed for treating malodors in air. One disclosed apparatus comprises a passive device whereby a media comprising a transition metal compound is placed near a VPHP source. The VPHP source may be solid material disposed within a pad or a supply of liquid material disposed adjacent to the pad. The transition metal compound may be coated onto the pad or may be media disposed within or otherwise supported by the pad. Embodiments with solid VPHP disposed within a coated filter pad are preferably disposable products while embodiments with a coated pad disposed near a liquid or solid VPHP source disposed outside of the pad may be rechargeable products.
[0035] Disposable pads with a solid source of the VPHP disposed therein may be conveniently used within or near garbage cans, litter boxes, shoes, laundry (diaper) hampers, etc.
[0036] Passive devices with a liquid source of VPHP may be provided in the form of a decorative vase with a transition metal compound media disposed above the liquid source of the VPHP. Various other decorative and functional embodiments will be apparent to those skilled in the art.
[0037] Other “active” or “mechanical” devices comprise an air movement mechanism for generating an air stream from ambient air that comprises air and malodorants. The apparatus may further comprise a vapor phase hydrogen peroxide generator and a media whose surface is coated with at least one transition metal element or compound. The vapor phase hydrogen peroxide generator is positioned “upstream” with respect to the air movement through the apparatus such that hydrogen peroxide vapor first becomes entrained in the malodorous air stream, followed by at least partial engagement/interaction with the filter media surface that is coated with at least one transition metal element or compound.
[0038] In one preferred embodiment, the air movement mechanism is a fan.
[0039] In another refinement, the VPHP source container is disposed upstream of the media, which is itself upstream from the air displacement mechanism. Thus, the air displacement mechanism draws the malodorous air stream across/through the VPHP source container, across and/or through the media and past/through the air displacement mechanism.
[0040] In another refinement, the apparatus further comprises a vented base disposed “downstream” from the air displacement mechanism and the media. Thus, the malodorous air passes across/through the VPHP source container, through/across the media, past the air displacement mechanism, and exits the apparatus via a vented base comprising a plurality of vent openings. An object which emits a fragrance may be positioned within the base.
[0041] In another refinement, the VPHP source container comprises a porous (gas permeable) pouch and the apparatus further comprises a structure which supports the porous pouch. In such a refinement, the vertical chimney may be connected to a central housing that accommodates the filter. The central housing may include vents for the axial flow of air. Further, the central housing can be connected to a vented base that accommodates and houses the air displacement mechanism and which includes at least one opening for the release of air that is passed through the vertical chimney, porous pouch, central housing and filter and past the air displacement mechanism. In another refinement, the vertical chimney is cylindrical in shape.
[0042] One preferred apparatus for treating malodors in air comprises an air movement mechanism for generating an air stream using ambient air that comprises indoor air and malodorants. The air movement mechanism is accommodated in a vented base comprising a plurality of vent openings. The vented base is connected to a central housing disposed on top of the vented base. The central housing accommodates a media comprising at least one transition metal element or compound and the central housing is disposed between the vented base and a chimney or top housing. The chimney accommodates a porous pouch containing solid peroxohydrate compound that serves as a VPHP generator/source. The central housing and chimney are vented so as to permit an axial airflow across and/or through the porous pouch, across/through the media, and to the air movement mechanism. The air movement mechanism accordingly draws the air stream and malodorants downward through the chimney and across and/or through the porous pouch where vapor phase hydrogen peroxide (VPHP) is entrained in the air stream before the malodorous air stream and VPHP pass across and/or through and a least partially engage the media where at least a portion of the malodorants react with VPHP on the media. Finally, the air stream, partially/fully depleted of malodorants, passes out of the apparatus through the openings in the vented base.
[0043] Other advantages and features will be apparent from the following detailed description when read in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] For a more complete understanding of the disclosed methods and apparatuses, reference should be made to the embodiment illustrated in greater detail on the accompanying drawings, wherein;
[0045] FIG. 1 is a side view of a media comprising a transition metal element or compound made in accordance with the present disclosure with a solid source of VPHP disposed within the media that can be used in both passive ( FIGS. 2-6 ) as well as active ( FIGS. 7-17 ) malodorants treatment systems;
[0046] FIG. 2 is a perspective view of a passive malodor treatment apparatus that includes a liquid source of VPHP disposed below a media;
[0047] FIG. 3 is an illustration of the use of the pad-type media of FIG. 1 on a laundry (diaper) hamper;
[0048] FIG. 4 is an illustration of the use of the pad-type media of FIG. 1 in a shoe;
[0049] FIG. 5 is an illustration of the use of the pad-type media of FIG. 1 on a litter box;
[0050] FIG. 6 is an illustration of the pad-type media of FIG. 1 on the underside of a lid of a kitchen garbage can;
[0051] FIG. 7 is a schematic diagram of a disclosed apparatus for catalytically treating airborne malodorants with vapor phase hydrogen peroxide; and at least one transition metal element or compound;
[0052] FIG. 8 is a schematic/front plan view of a disclosed apparatus for catalytically treating airborne malodorants with vapor phase hydrogen peroxide; and at least one transition metal element or compound;
[0053] FIG. 9 is a front plan/perspective view of the apparatus shown in FIG. 8 ;
[0054] FIG. 10 is a bottom plan view of the upper housing or chimney showing an annular hydrogen peroxide emitting pouch;
[0055] FIG. 11 is a perspective view of the lower vented base and middle housing that accommodates a media that is coated with at least one transition metal element or compound;
[0056] FIG. 12 is a perspective view illustrating the installation of the media comprising a transition metal elements(s)/compound(s) into the middle housing;
[0057] FIG. 13 is a perspective view illustrating installation of the upper housing or chimney that is equipped with the hydrogen peroxide emitting pouch onto the middle housing that accommodates the media comprising the transition metal element(s)/compounds(s);
[0058] FIG. 14 is a perspective view of the vented base housing and fan of the disclosed apparatus as illustrated generally in FIG. 9 and FIGS. 11-13 ;
[0059] FIG. 15 is a perspective/sectional view of the vented base housing, a fan and middle housing that accommodates the media of the disclosed apparatus as shown in FIG. 12 ;
[0060] FIG. 16 is a front plan view of a disclosed apparatus generally illustrating the induced airflow stream; and
[0061] FIG. 17 is a top plan view of the apparatus as shown in FIG. 16 generally illustrating the induced airflow exiting the apparatus.
[0062] It should be understood that the drawings are not necessarily to scale and that the disclosed embodiments are sometimes illustrated diagrammatically in partial views. In certain instances, details which are not necessary for an understanding of the disclosed methods and apparatuses or which render other details difficult to perceive may have been omitted. It should be understood, of course, that this disclosure is not limited to the particular embodiments illustrated herein
DETAILED DESCRIPTION
[0063] Hydrogen peroxide in its pure form is a clear, colorless liquid having a slightly sharp acrid odor and a freezing point of −0.4° C. Pure liquid hydrogen peroxide exhibits a vapor pressure of about 2 mmHg at 25° C., somewhat less than that of water (˜24 mmHg at 25° C.). Aqueous solutions of hydrogen peroxide exhibit a mixed vapor phase composition of water vapor and vapor phase hydrogen peroxide, as expected for a mixture of two miscible volatile liquids. See, for example, Hydrogen Peroxide , Kirk-Othmer Encyclopedia Chemical Technology, 4 th Edition, Volume 13, 1995, Wiley-Interscience Publication, and references therein.
[0064] Inorganic and organic compounds containing molecular hydrogen peroxide as solid/crystalline adducts are referred to as peroxohydrates or perhydrates. Many such materials are known in the commercial and technical literature, including such materials as sodium carbonate peroxohydrate 2Na 2 CO 3 .3H 2 O 2 (sodium percarbonate); ammonium carbonate peroxohydrate (NH 4 )CO 3 .3H 2 O 2 ; urea peroxohydrate, CO(NH 2 ) 2 .H 2 O 2 (urea peroxide); sodium sulfate peroxohydrate, 2Na 2 SO 4 .H 2 O 2 .H 2 O 2 ; and various peroxohydrate phosphate salts. Descriptions of various peroxohydrates can be found in “Hydrogen Peroxide, Peroxohydrates”, Kirk-Othmer Encyclopedia of Chemical Technology, 4 th Edition, Volume 13, 1995, Wiley-Interscience Publication, and therein. A polymer-containing peroxohydrate of poly(vinyl pyrrolidone), PVP.H 2 O 2 , where the hydrogen peroxide content of the compound is variable up to about 22 wt % of the composition, is commercially available as Peroxydone® from the ISP Corporation, Wayne, N.J., USA.
[0065] Aqueous liquid compositions containing hydrogen peroxide, wherein the pH of the solution is about 8 or below, can be passively evaporated in an indoor environment to produce useful amounts of vapor phase hydrogen peroxide with utility toward the elimination or reduction of malodors from the air space and surfaces of the indoor environment. Alkaline aqueous hydrogen peroxide solutions are not stable. Therefore, it is desirable to utilize pH neutral to mildly acidic aqueous hydrogen peroxide compositions in the pH range of about 1 to about 8. This provides acceptable long-term stability of the aqueous hydrogen peroxide composition. More preferably, the pH of the liquid composition is in the range of about 2 to about 7. Most preferably, the pH of the liquid composition is in the range of about 3 to about 6, provided for optimal product stability.
[0066] The aqueous pH neutral to mildly acidic aqueous hydrogen peroxide compositions may be homogenous solutions or heterogeneous dispersions containing suspended solids. The viscosity of the liquid hydrogen peroxide compositions may range from that of a “water-thin” fluid (less than about 10 cp at 25° C.) to that of a highly viscous, rigid gel, paste or suspension (about 100,000 cp or greater at 25° C.). Viscosity building agents may include peroxide-stable surfactant systems, peroxide-stable polymers, as well as various solid inorganic thickening agents/fillers such as alumina, silica, and natural/synthetic clays.
[0067] The concentration of hydrogen peroxide in the aqueous compositions may comprise up to about 50 wt % of the composition, preferably less than about 10 wt % of the composition and most preferably from about 0.5% to 8 wt % of the composition. The aqueous compositions may include minor amounts of the other ingredients, including fragrance ingredient and fragrance solubilizing agents such as surfactants or solvents, and/or colorant(s) for aesthetic purposes. For optimal stability, the aqueous compositions may also include one or more hydrogen peroxide-stabilizing agents, such as, for example, stannate compounds, phosphate salts, organophosphonates, and various chelating agents derived from aminocarboxylates or aminophosphonates. Various peroxide-stabilizing agents are disclosed in “Hydrogen Peroxide, Stabilization”, Kirk-Othmer Encyclopedia of Chemical Technology, 4 th Edition, Volume 13, 1995, Wiley-Interscience Publication and the referenced therein, incorporated herein by reference. Additional ingredients may include peroxide-stable acids for pH adjustment, including but not limited, to sulfuric acid, adipic acid, glutaric acid, succinic acid, and polyacrylic acid.
[0068] Various dispensing devices are suitable for malodor reduction or elimination applications using passive generation of vapor phase hydrogen peroxide from the low viscosity aqueous hydrogen peroxide-containing solutions. Liquid wicking devices, such as container-dispensing systems for liquid air fresheners, are especially useful as they may be exposed to an induced air stream within a housing relatively easily. Materials of construction for such devices are selected so as to provide for the integrity of the container-dispenser with respect to the oxidizing and corrosive nature of the aqueous hydrogen peroxide solutions described herein.
[0069] Viscous gels or suspensions may be contained within dish, or cup-type containers accommodated within a housing and having at least one opening so as to permit the passive evaporation of the hydrogen peroxide and entrainment of the generated VPHP into the induced air stream, producing a suitable concentration of vapor phase hydrogen peroxide in the air stream before it engages the media.
[0070] Various mechanical devices may be utilized in combination with hydrogen peroxide-containing viscous gels or suspensions of the present invention. These devices include those which will enhance effective generation of vapor phase hydrogen peroxide within the indoor environments by utilizing mild heating of the compositions, which are enclosed within appropriate containers, pouches or packages. Such heating devices, used to promote the dispensing of volatile liquid compositions, include those disclosed in U.S. Pat. Nos. 3,633,881; 4,020,321, 4,969,487; 5,038,394; 5,290,546; 5,647,053; 5,903,710; 5,945,094; 5,976,503; 6,123,935; and 6,862,403 B2, incorporated herein by reference. Fan type devices are employed to generate an air stream with entrained VPHP which is then flowed across and/or through the media. Such fan type devices include those disclosed in U.S. Pat. Nos. 4,840,770; 5,370,829; 5,547,616; 6,361,752 B1 and 6,371,450 B1, incorporated herein by reference.
[0071] Certain solid peroxohydrate compounds, when exposed to ambient indoor air, will surprisingly liberate useful amounts of vapor phase hydrogen peroxide with utility towards reduction or elimination of malodors from the air space and surfaces of the indoor environment. These peroxohydrate compounds may comprise part, or all, of solid compositions which sublime hydrogen peroxide from the solid composition into the vapor phase at ambient room temperatures. The amount of peroxohydrate utilized in the solid composition will depend on the hydrogen peroxide content of the peroxohydrate and the release rate of hydrogen peroxide vapor from a given peroxohydrate, relative to the desired rate of release for the composition containing the peroxohydrate. Ambient indoor air generally contains a significant amount of water vapor, and alkaline peroxohydrate compounds are unstable in the presence of moisture. Thus, it is necessary to utilize pH neutral to slightly acidic peroxohydrate compounds. The terms “pH neutral to slightly acidic peroxohydrate compound’ refers to a peroxohydrate compound wherein the pH of a concentrated (˜5 wt % in water) solution of the compound in purified water is less than about a pH of about 9 when the solution is at a temperature range of from about 20 to about 25° C.
[0072] Examples of suitable mildly acidic hydrogen peroxide-containing solid peroxohydrate compounds include urea peroxohydrate, CO(NH 2 )2.H 2 O 2 ; sodium sulfate peroxohydrate, 2Na 2 SO 4 .H 2 .2OH 2 .H 2 , and a peroxohydrate of poly(vinyl pyrrolidone) polymer, PVP.H 2 O 2 , where the hydrogen peroxide content of the polymeric PVP peroxohydrate can range up to about 22 wt %. The solid composition containing one or more peroxide-containing peroxohydrate compounds may also include one or more non-peroxide containing filler solids, such as inert inorganic salts, alkaline earth sulfate salts, silica, alumina and talc.
[0073] The solid composition may comprise a powder, compressed tablet, crystalline, solid, or other readily recognizable solid forms. The hydrogen peroxide content of the solid composition can be as high as about 50 wt % hydrogen peroxide, but preferably about 25 wt % or less for reasons of, among other things, product processing and stability. More preferably, the solid compositions may have hydrogen peroxide content in the range of from about 5 to about 25 wt %. Most preferably, the solid compositions may have a hydrogen peroxide content in the range of from about 10 to about 22 wt %.
[0074] The solid composition may include minor amounts of other ingredients, including fragrance ingredients, and/or colorant(s) for aesthetic purposes. Minor amounts of other ingredients, such as surfactants, solvents, and processing aids (e.g., anti-caking, mold release agents, shape-forming agents or binders, etc.) may also be included in the solid compositions. For optimal peroxide stability, the compositions may also include one or more hydrogen peroxide-stabilizing agents, such as stannate compounds, phosphate salts, organophosphonates, and various chelating agents derived from aminocarboxylates or aminophosphonates. Various peroxide-stabilizing agents are disclosed in “Hydrogen Peroxide, Stabilization”, Kirk-Othmer Encyclopedia of Chemical Technology, 4 th Edition, Volume 13, 1995, Wiley-Interscience Publication and references therein, incorporated herein by reference.
[0075] The solid hydrogen peroxide-containing VPHP-generating compositions may be packaged within various types of porous containers which permit the transmission of vapor phase hydrogen peroxide into the indoor air space and permit the flow of an air stream across and/or through the container. These packages include pouches or bags, which allow for the transmission of hydrogen peroxide vapor and an induced air stream through the package walls. The solid compositions may also be contained within a cup or dish having one or more suitable openings which permit vapor phase hydrogen peroxide transmission from within the container into the indoor air space. If the solid hydrogen-peroxide-containing compositions are of a powdered, granule, or particulate form, a container such as a dish or cup may include a physical barrier preventing the solid from being discharged from the container by shaking, inverting, or the like. Appropriate physical barriers include a covering of fabric or screen-type material of sufficiently small pore/mesh size, such that the solid powder or particulate cannot pass through the fabric/screen, however the pores in the covering will allow for the transmission of vapor phase hydrogen peroxide into said air stream and downstream towards the disclosed media disposed within the apparatus.
[0076] Preferred sources of hydrogen peroxide are provided in a powder form disposed within a pouch. Preferably, the hydrogen peroxide source is a peroxohydrate compound derived from hydrogen peroxide and polyvinyl pyrrolidone, sold as Peroxydone® by ISP Corporation, Wayne, N.J., USA. The PVP.H 2 O 2 may be provided in a Tyvek® pouch, also sold by DuPont of Wilmington, Del., USA. The pouch may be provided in a variety of shapes and sizes including but not limited to the annular-shaped pouch 121 shown in FIG. 10 .
[0077] The inventive apparatus serves to reduce/eliminate malodorous substances from an indoor air stream, by passing said air stream through a device which mixes VPHP with the air stream, followed by interaction of said air stream with a media comprising or coated with at least one transition metal element or compound.
[0078] Preferred transition metal(s) may be selected from the group consisting of titanium, vanadium, manganese, iron, cobalt, molybdenum, tungsten, nickel, silver, copper and zinc. Most preferred transition metal(s) are selected from the group consisting of titanium, vanadium, manganese, iron, copper, molybdenum, tungsten, and zinc for reasons of low-cost, low toxicity and minimal environmental impact. Various titanium-containing compounds are especially desirable. Among these, transition metal compounds selected from the group consisting of titanium dioxide and titanium dioxide hydrates, and mixtures thereof are most desirable in terms of cost and low environmental impact.
[0079] One or more catalyst promoter compounds may be used such as non-transition metal oxides, hydroxides, carbonates, borates, phosphates, halides, silicates, aluminates, nitrates, sulfates, organo-carboxylates, stannates, and bismuthates. Illustrative examples include (without limitation): alkali metal and alkaline earth halides, alkaline earth oxides/hydroxides, alkali metal and alkaline earth carbonates, alkali metal and alkaline earth sulfates, alkali metal and alkaline earth silicates, silica, alkali metal and alkaline earth aluminates, alumina, alkali metal and alkaline earth borates, boric acid, alkali metal and alkaline earth phosphates, Sn oxide/hydroxide compounds, and Bi oxide/hydroxide compounds.
[0080] The disclosed device disclosed herein employs a media, the surface of which comprises or is at least partially covered/coated with at least one transition metal element or compound. The media may be fibrous or non-fibrous in nature. The media may be permanent within the device (i.e., not intended for replacement over the useful lifetime of the device) or it may be replaceable (i.e., periodic replacement of “spent” filters, with installation of new/fresh media). The media may be made from a variety of materials including woven fabric, non-woven fabrics, glass wools, or sintered glass beads. The media comprises or is at least partially coated with a composition containing at least one transition metal element or compound. The loading of said transition metal coating on or into the media will range from about 0.001 wt % to about 50 wt %. Examples of preferred media include synthetic woven fabrics, synthetic non-woven fabrics, and glass wools. Highly preferred media include synthetic non-woven fabrics. Representative examples of various synthetic non-woven fabrics (fiber compositions and manufacturing processes) can be found in “Non-woven Fabrics”, Kirk-Othmer Encyclopedia of Chemical Technology, 4 th Edition, John Wiley & Sons, Inc., copyright © 1996, incorporated herein as a reference. Non-woven fabrics composed of synthetic fiber materials which are resistant to the oxidizing action of hydrogen peroxide are especially preferred. Such oxidation-resistant materials include polyolefin (especially polyethylene and polypropylene) and polyester fibers.
[0081] Examples of preferred media include synthetic non-woven fabrics comprised of polyester and/or polyolefin fibers, wherein said fibers are at least partially covered or coated with at least one transition metal element or compound. Highly preferred coatings contain titanium dioxide. In this embodiment, the media is coated with a material comprising from about 0.001 to about 50 wt % (combined) of titanium dioxide and/or hydrated titanium dioxide. Said transition metal element(s) and compound(s) may be adhered or bonded to the surface of the media through the use of various inorganic or organic adhesion agents. Preferably such adhesion agents are resistant to oxidation by hydrogen peroxide.
[0082] In a preferred representative embodiment, the filter comprises from about 90 to about 99.99 wt % non-woven air-spun polyester fibers, and from about 0.01 to about 10 wt % of a powdered coating that comprises a mixture of titanium dioxide and hydrated titanium dioxide.
[0083] Low concentrations of vapor phase hydrogen peroxide contained within an malodorous indoor air environment, generated using methods employing passive evaporation of pH neutral to mildly acidic aqueous liquid compositions containing hydrogen peroxide, or sublimation of hydrogen peroxide vapor from solid compositions containing at least one pH neutral to mildly acidic solid hydrogen peroxide-containing peroxohydrate compound, where said VPHP and malodor interacts with at least one transition metal element or compound, have excellent utility towards reduction or elimination of malodors from the air space and surfaces of the indoor environment. In particular, such VPHP sources combined with at least one transition metal element/compound acting as a catalyst are useful for the reduction or elimination of tobacco smoke odors and various other malodors, especially those containing reduced sulfur and nitrogen compounds, from the air space within indoor environments.
[0084] Passive odor removing systems are illustrated in FIGS. 1-6 . In FIG. 1 , a non-woven media or pad 25 is shown with solid VPHP sources 21 that can be in powdered, tablet or granular form. The non-woven fibers 25 ′ are coated with a catalyst material, such as a transition metal compound, such as titanium dioxide. The pad 25 may include one or more adhesive strips 15 for adhering the pad 25 in place such as to a laundry hamper ( FIG. 3 ), in a shoe ( FIG. 4 ), to a litter box ( FIG. 5 ) or to a garbage can ( FIG. 6 ).
[0085] FIG. 2 illustrates a different type of passive device that includes a container 11 with a cylindrical sidewall 14 and bottom 15 . A liquid source of VPHP 21 ′ is provided inside the container 11 and a coated pad 25 ′ (without a solid source of VPHP disposed therein) is accommodated in the opening 23 of the container 11 . Ambient air, containing malodors engages the pad 25 ′ and comes into contact with the VPHP exiting the container 11 through the pad 25 ′.
[0086] In contrast to the passive devices of FIGS. 2-6 , active apparatuses 10 a , 100 are illustrated in FIGS. 7 and 8 - 17 . Turning to FIG. 7 , the apparatus 10 a includes a base housing 11 a which accommodates a fan 12 and which provides openings or vents 13 in the sidewall 14 a or, in the alternative, vents 13 a disposed in the end or bottom wall 15 a . The base 11 a both houses and supports the fan 12 , which is illustrated in greater detail in connection with the embodiment 100 of FIGS. 14 and 15 . Still referring to FIG. 7 , the fan 12 is powered by a motor 16 which, in turn, is linked to a control module or user interface 17 . The fan 12 creates an air stream flowing in the direction of the arrow 18 towards and through the upper or chimney section 19 . The chimney section 19 accommodates a vapor phase hydrogen peroxide (VPHP) generator 21 a which, in one refinement, comprises a pouch containing several grams of a powdered peroxohydrate compound such as Peroxydone®. A dust collector or preliminary filter 22 covers the open end 23 of the chimney or housing 19 .
[0087] The chimney 19 , with the VPHP generator 21 a is connected to a middle housing 24 which accommodates the primary filter 25 a . The filter 25 a preferably comprises a non-woven polyester coated with one or more transition metal compounds such as titanium dioxide and aluminum dioxide. It has been found that the combination of VPHP and a transitional metal compound such as titanium dioxide provide a synergistic effect with respect to oxidizing airborne malodorous materials, thereby resulting in the accelerated reduction/elimination of the malodor material from an indoor airspace. The apparatus 10 provides an excellent mechanism for exploiting this synergy.
[0088] The release of VPHP may be enhanced by employing a heater 26 which would also be linked to the interface of 17 . Further, additives may be included in the VPHP generator 21 a as discussed above or additional materials may be entrained in the air stream by either injection or evaporation. Therefore, additional materials may be provided by one or more supply chambers shown schematically at 27 . The supply chamber 27 may also be equipped with a heating device which would be linked to the interface 17 .
[0089] Turning to FIG. 8 , an apparatus 100 is shown in a more preferred upright configuration. The apparatus 100 includes a chimney or top section 119 , a middle housing section 124 and vented base 111 . The fan 112 draws air downward in the direction of the arrow 118 through the VPHP generator 121 where hydrogen peroxide vapor is entrained in the air stream before the air stream passes across and/or through the coated filter 125 . Malodorants contained within the air stream may then by catalytically oxidized by the hydrogen peroxide vapor in combination with the transition metal element/compound that coats the filter 125 . The “cleaned” air is then distributed out through the vents 113 as shown. An optional heater is shown at 126 which is linked to the interface 117 which, in turn, is also linked to the fan motor 116 and an optional active dispenser/heater 127 . The optional dust filter/collector is shown at 122 .
[0090] Turning to FIG. 9 , the apparatus 100 is shown with the preferred configuration of the vents 113 in the lower base housing 111 for providing the airflow patterns described in greater detail below in connection with FIGS. 16-17 . The middle housing 124 , upper housing 119 and lower base housing 111 may be manufactured from the same plastic, and preferably opaque, material. The optional dust filter/collector 122 is shown with a tab 122 a for facilitating insertion and removal of the filter 122 from the top opening 123 of the chimney 119 .
[0091] FIG. 10 is a bottom plan view of the chimney or upper housing 119 . A grate or support for the VPHP generator 121 is provided by a series of radial spokes 131 connected to a center plate 132 . Turning to FIG. 13 , the chimney 119 fits on top of the middle housing 124 . The middle housing 124 also includes a grate 135 comprising a plurality of radial spokes 133 connected to a series of concentric rings 134 . The grate 135 supports the coated filter 125 (not shown in FIG. 10 ; see FIG. 11 ). FIGS. 12 and 13 illustrate the insertion of the coated filter 125 into the middle housing 124 and the subsequent placement of the chimney 119 on top of the middle housing 124 .
[0092] FIG. 14 is a perspective view of the lower base housing 111 , which accommodates the fan or air movement mechanism 112 . The middle housing 124 and chimney 119 are removed. The fan 112 includes a shaft 141 coupled to the motor 116 (see FIGS. 8 and 15 ) and a plurality of radial blades 142 .
[0093] FIGS. 16-17 illustrate the airflow generated by the apparatus 100 . Air is drawn downward in the direction of the air 118 by the air displacing action of the fan 112 . VPHP becomes entrained in the air stream as it passes through the chimney 119 which includes the VPHP generating pouch 121 . The air stream, that includes malodor-causing molecules as well as VPHP, then passes across and/or through the coated filter 125 of the middle of the housing 124 . Malodor-causing molecules are then catalytically oxidized by hydrogen peroxide in the presence of the transition metal element/compound that is coated on the filter 125 . The vents 113 in the base housing 111 provide the airflow pattern illustrated in FIGS. 16-17 as further explained in co-pending and commonly-assigned U.S. patent application Ser. No. 11/754,584, incorporated herein by reference.
[0094] The following Examples 1-3 illustrate the preparation of inventive media containing or comprising a transition metal coating. The use of said coated media from Examples 1 and 2 with disclosed apparatus 100 (referenced below as a flow-through device) to reduce the concentration of two model malodor compounds from the airspace within a sealed test chamber is provided in Examples 4 and 5, below. The said coated media from Example 3 was used in a static sealed test chamber to reduce the concentration of a model compound in Example 6. Quantitative analytical results for these malodor reduction procedures are provided in Tables 1-3.
EXAMPLES 1-3
Preparation of Non-Woven Media Coated with Transition Metal Compound
[0095] Polyester fiber non-woven filter were cut using a circular die 4 inches in diameter. The non-woven filter (1.4 grams, weight accurately known, 4 inch diameter, 0.25 inch depth) were mounted vertically 5 inches in front of a pump sprayer containing a 1 weight % solution of Tyzor® TPT in isopropyl alcohol (Tyzor® TPT=99+% Ti(iso-propoxide) 4 , E.I. du Pont de Nemours and Company, Wilmington, Del., USA). Six grams of the 1% Tyzor® solution was sprayed evenly onto both sides of the filter material. The filter material was allowed to air dry at 22° C. and approximately 60% relative humidity for at least 24 hours prior to use, thereby converting the Ti(iso-propoxide) 4 to hydrous titanium dioxide (DuPont Tyzor® Organic Titanates General Brochure). The filter material had a weight gain of approximately 20 mg, attributable to the hydrated titanium dioxide. The non-woven material had a noticeable white film deposited on the filter. The presence of hydrated titanium dioxide was confirmed by a visible color change to bright yellow upon exposure to hydrogen peroxide vapor.
[0096] Example 2 is the same as example 1, except that 5% Tyzor® solution was used in place of the 1% solution. The filter material has a weight gain of approximately 100 mg, attributable to the hydrated titanium dioxide.
[0097] Example 3 is the same as example 2, except that the circular non-woven filter was replaced with a rectangle of thin non-woven sheet measuring 4.5 inches by 3.5 inches. Two non-woven rectangle sheets were overlaid and sealed on 3 sides to create a pouch to which powder could be added later. The non-woven sheet had an approximate weight gain of 100 mg, attributed to the hydrated titanium dioxide.
EXAMPLES 4 AND 5
Removal of Pentane Thiol Vapors in the Presence of Media Coated with Transition Metal Compound and Vapor Phase Hydrogen Peroxide, Using Flow Through Device
[0098] Example 4: A 25 ft 3 sealed acrylic chamber was set-up to contain a mixing fan, hot plate, and flow through device having 2 filters and a vapor phase hydrogen peroxide source (a cylindrical filter paper dosed with 30 μl of a 50% aqueous hydrogen peroxide solution). The chamber atmosphere is interfaced with a gas chromatography apparatus (“Z-nose” 4100 Vapor Analysis System, Electronic Sensor Technology, Newbury Park, Calif., USA). The flow through device was set-up containing a blank (non-coated) non-woven filter, a cylindrical filter paper dosed with 30 μl of a 50% aqueous hydrogen peroxide solution, and the transition metal coated non-woven filter (prepared in example 1). Ten μl of an 8 wt % pentanethiol solution in methanol was added to the hot plate as the malodor. The malodor was volatilized by heating the hot plate for 10 minutes, using the mixing fan to quickly reach equilibrium within the sealed chamber. Analytical Z-nose date was recorded every 2.5 minutes throughout the course of the experiment. The experiment had three time regimes: 60 minutes of a static chamber followed by 60 minutes of the flow through device operating followed by an additional 60 minutes of static chamber. The static chamber readings allow for the determination of the natural removal of the malodor due to chamber sink effects and potential leak pathways which can then be accounted for in the flow through device regime. The analytical % malodor reduction was corrected for using the static region data. The analytical % reductions of the malodor in the test chamber airspace are provided in Table 1 for pentanethiol. Appropriate controls were also performed, and these results are included in Table 1 for comparison.
[0099] Example 5: same as Example 4, except using 5 μl of neat dibutylsulfide malodor liquid and transition metal coated non-woven filter prepared in Example 2. The analytical % reductions of the malodor in the test chamber airspace are provided in Table 2 for dibutylsulfide. Appropriate controls were also performed, and these results are included in Table 2 for comparison.
[0000]
TABLE 1
Removal of Pentanethiol Vapors with Transition Metal Compound-Coated
Filter in Combination with Vapor Phase Hydrogen Peroxide (VPHP)
Flow-Through Device
% Reduction
% Reduction
Average
Set-up
Experiment 1
Experiment 2
% Reduction
Blank Filters Only
4.58
5.63
5.11
Blank Filters + VPHP
35.79
29.94
32.87
Tyzor Filter Only
6.63
14.34
10.49
Tyzor Filter + VPHP
50.02
54.71
52.37
[0000]
TABLE 2
Removal of Dibutylsulfide Vapors with Transition Metal Compound-
Coated Filter in Combination with Vapor Phase Hydrogen Peroxide
(VPHP)
Flow-Through Device
% Reduction
% Reduction
Average
Set-up
Experiment 1
Experiment 2
% Reduction
Blank Filters Only
4.63
10.44
7.54
Blank Filters + VPHP
12.16
13.27
12.72
Tyzor Filter Only
18.19
18.31
18.26
Tyzor Filter + VPHP
96.12
90.77
93.45
EXAMPLE 6
Removal of Pentanethiol Vapors in the Presence of a Thin Non-Woven Media Coated with a Transition Metal Compound and Vapor Phase Hydrogen Peroxide, a Static Device
[0100] Example 6: A 2.3 ft 3 acrylic chamber was set-up for experiments with the chamber atmosphere interfaced with a gas chromatography apparatus (“Z-nose”), similar to example 4. Within the acrylic chamber, a small weighing dish was position across the chamber from the Z-nose to hold the malodor solution and a low volume interior chamber was constructed to isolate the non-woven media from the chamber. 10 μl of a 0.8 wt % pentanethiol solution in methanol was added to the weighing dish as the malodor. The malodor was allowed to stabilize in the chamber for 10 minutes before sampling began. Analytical Z-nose data was recorded every 2.5 minutes throughout the course of the experiment. The experiment had three time regimes: 10 minutes of a static chamber for the malodor to evaporate and mix, followed by 60 minutes of recording the natural decay of the malodor in the chamber, followed by 60 minutes of the non-woven media exposed to the chamber. The only air flow within the chamber was generated by the Z-nose sampling pump during the course of the experiment. In experiments where the VPHP was used, a 10 μl dose of a 50% aqueous hydrogen peroxide solution was positioned within the interior chamber along with the non-woven media. The analytical % reduction was corrected for by subtracting the reduction in the background region. The analytical % reductions of the malodor in the test chamber airspace are provided in Table 3. Appropriate controls were also performed, and these results are also included in Table 3 for comparison.
[0000]
TABLE 3
Removal of Pentanethiol vapors with a transition metal compound-
coated non-woven in combination with vapor phase hydrogen peroxide
(VPHP)
Static Device
% Reduction
% Reduction
Average
Set-up
Experiment 1
Experiment 2
% Reduction
Blank Filters Only
13.48
14.04
13.76
Blank Filters + VPHP
23.19
17.08
20.13
Tyzor Filter Only
26.57
36.07
31.32
Tyzor Filter + VPHP
57.33
60.75
59.04
[0101] The above data in Tables 1-3 illustrates the synergistic effect of the media coated with a transition metal compound when used in combination with vapor phase hydrogen peroxide as employed in the inventive flow through and static devices described herein.
[0102] While only certain embodiments have been set forth, alternatives and modification will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the scope of this disclosure and the appended claims. | Compositions, methods and apparatuses for reducing or eliminating malodors from indoor air are described. A method is provided for the reduction or elimination of malodors from indoor air using vapor phase hydrogen peroxide generated from either evaporation from a pH neutral to mildly acidic aqueous-based liquid composition or sublimation from a solid composition containing at least one pH neutral to mildly acidic solid hydrogen peroxide-containing compound. The vapor phase hydrogen peroxide (VPHP) engages a media coated with at least one transitional metal element or compound in the presence of air that contains malodorous compounds. The combination of the vapor phase hydrogen peroxide and the transitional metal compound, which acts as an oxidation catalyst, provides increased efficacy of malodor molecule oxidation. One execution of said apparatus employs a disposable porous non-woven filter pad, coated with one or more transition metal compounds, and a solid source of VPHP also disposed within said apparatus. Malodor-containing air engages the coated filter pad in the presence of the VPHP and the malodorants are effectively oxidized. Preferably, the apparatus incorporates one or more chemical mechanisms involving prominent color change(s) in the presence of VPHP, thus indicating to the user whether the device is functional or depleted of VPHP. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an improved high chair system for a child, and more particularly, to a reclinable high chair system with sloping armrests and with one or more trays.
2. Description of the Related Art
Conventional high chairs for children typically employ arm rests that are affixed to the side of the chair and assist in the support of the high chair's tray. The high chair tray is typically equipped with a conventional gripping device to attach the tray to the chair. This tray gripping device is structured so that it can grasp the arm rests mounted on the high chair. Thus, although the tray of the typical high chair is removable, the arm rests remain affixed to the chair, and can constitute an obstruction during certain uses and a general inconvenience. During feeding, for example, the conventional arm rests often prevent the conventional high chair from being placed conveniently close to the dinner table, and also are an obstruction and prevent easy access to the child.
Furthermore, conventional high chairs suffer from the drawback of providing only a single tray and fail to provide a flexible multi-tray system which can be adapted for multiple uses and which can be placed in multiple configurations.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a flexible high chair system which can be used in multiple configurations including various reclining positions and which can be used with a plurality of trays. Another object of the present invention is to provide a high chair seat which includes sloping arm rests that overcomes the deficiencies of the prior art. Yet another object is to provide a high chair seat with sloping arm rests which can receive a restraining structure (preferably a lower tray), with the restraining structure being capable of receiving an upper tray.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described, the invention provides for a high chair system for a child adapted for use in multiple configurations comprising a leg structure, a chair seat connected to and supported by the leg structure and including an arm rest portion which includes a mounting structure, a restraining structure including an engagement portion adapted to removably engage with the mounting structure of the arm rest portion, the lower tray further including an edge mounting structure, and an upper tray including a locking structure to removably engage with the edge mounting structure of the lower tray.
In another aspect, the invention provides for an improved high chair seat for allowing easy access to a child, the seat comprising a back rest portion to support the back of the child, a seat portion substantially perpendicular to the back rest portion, and a pair of arm rest portions which slope from an intermediate point of the back rest portion generally toward a front point of the seat portion.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate one embodiment of the invention and together with the written description serve to explain the principles of the invention. In the drawings:
FIG. 1 is a perspective view of a high chair according to the present invention;
FIG. 2 is a side view of a high chair according to the present invention;
FIG. 3 is an exploded view of a chair seat, lower tray, and upper tray according to the present invention;
FIG. 4 is a plan bottom view of the lower tray according to the present invention; and
FIG. 5 is a plan bottom view of the upper tray according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings.
FIG. 1 shows a high chair 100 which includes a foldable leg structure 120 and a high chair seat 160. The foldable leg structure 120 generally includes a front leg section 122 and a rear leg section 124. The front leg section preferably includes a U-shaped tube comprising two vertical members 126 and 128 and a lower horizontal member 130 with feet 132 and 134 provided at the corners. The rear leg section 124 is connected to the front leg section 122 at a pivot point 136 to allow the rear legs to fold forward. A folding guide 138 is attached to the rear leg section 124 with a slidable connection and is connected to the front leg section 122 with a pivoting connection. When the lower legs are folded, a sliding portion 139 on the rear leg section 124 slides through channel 140 to facilitate the folding of the rear leg section 124 to the closed position. The folding guide 138 is more clearly shown in FIG. 2.
FIG. 2 is a side view of the high chair system 100. As can be seen, the upper portion of the front leg section 122 includes an extension portion 200 with a chair pivot rib 202 attached thereto. The chair pivot is achieved by having the tubes 126 and 128 pass through the chair pivot rib 202 extending from the rear of the high chair seat 160. The chair pivot rib is generally circular and allows tube 128 to pivot therein. The high chair seat 160 pivots within the chair pivot rib 202 to adjust between a sitting up position or a reclining position. Attached to the bottom of the high chair seat 160 is a guide member 204 to adjust the reclining position of the high chair seat 160. The guide member 204 includes a slot 206 with several stops 208. The guide bar 210 is disposed within the slot 206 and engages the stops 208 at various reclining positions. FIGS. 1 and 2 shows the high chair seat in a fully upright position. In the preferred embodiment, three stops 208 are provided in the guide member 204 to facilitate an upright, semi-reclined, and fully reclined configuration.
FIG. 3 shows the high chair seat 160 in more detail and includes a restraining structure and an upper tray 360. It should be understood that the restraining structure in addition to a restraint belt (not shown) generally functions to restrain the child and prevent slipping or falling out of the chair seat. The preferred embodiment includes a lower tray 330 which surrounds the child and includes a vertical member extending between the legs of the child. The high chair seat 160 generally includes a back rest portion 302, a seat portion 304, and a leg rest portion 306. Preferably, a cushion 307 is provided adjacent to the backrest portion 302 and the seat portion 304. A pair of arm rest portions 308 are shown on either side of the seat portion 304. The back rest portion 302 supports the back of the child. The seat portion 304 is substantially perpendicular to the back rest portion 302, and generally supports the weight of the child. The leg rest portion is substantially perpendicular to the seat portion 304. In the preferred embodiment, the arm rest portions 308 are integral with and connected to the back rest portion 302, the seat portion 304, and the leg rest portion 306.
The arm rest portions 308 are connected to the back rest portion 302 at an intermediate point of the back rest portion 302 and generally slope toward the front of the seat portion 304. The intermediate point of the back rest portion 302 is generally indicated by arrow 212 in FIG. 2 and the front of the seat portion 304 is generally indicated by arrow 214 in FIG. 2. A preferred slope is shown in FIG. 2.
As can be seen, the arm rest portions 308 and the reclining features described above provide several advantages. For example, the arm rest portions 308 allow the chair seat 160 to be positioned closely to a table. The sloping aspect of the arm rest portions 308 advantageously allows for tables of varying heights to be accommodated. Furthermore, the arm rest portions 308 provide for easy access to the child because the sides of the child may be reached directly. Dropped food or toys can be easily retrieved by a caregiver. Also, in a reclined position, the chair seat 160 is particularly useful for infants as they may be unable to sit up straight, and the arm rests 308 provide easy access, for example, during feedings.
Each of the arm rest portions 308 further includes a mounting structure adapted to receive a restraining structure, such as a lower tray 330. In particular, the preferred embodiment includes a receiving orifice 310 (most preferably a slot) on each of the arm rest portions 308 and a tab 312 on the arm rest portion 308 as a mounting structure to receive the lower tray 330.
It should be understood that the restraining structure (and the restraint belt) generally functions to restrain the child and prevent slipping or falling out of the chair seat. The preferred embodiment includes a lower tray 330 which surrounds the child and includes a vertical member 344 extending between the legs of the child to prevent the child from slipping through and underneath the lower tray 330. The lower tray 330 generally includes a tray area 332 which may be used for the storage of small food items or toys. The lower tray 330 also includes two arm rest extensions 334. The arm rest extensions 334 include a smooth upper surface 336 for use as arm rests, and a sloping lower surface 338 at an appropriate slope to engage with the arm rest portions 308. Of course, a child safety belt (not shown) is also preferably included to prevent the child from slipping or falling out of the chair seat. It should be understood that the tray area 332 is preferred, but not required for various embodiments of the present invention. For example, the lower tray 330 could simply provide a safety bar and vertical member to secure the child within the high chair in some embodiments.
In the preferred embodiment, the restraining structure includes an engagement portion, preferably including a lower engagement portion and an upper engagement portion that connect with the mounting structure of the arm rest portions 308 to secure the restraining structure to the chair seat. In particular, the preferred embodiment includes a pair of tabs 340 as the lower engagement portion, and a flexible locking arm 342 as the upper engagement portion. To connect the restraining structure to the chair seat, the tabs 340 are inserted into the receiving orifice 310, and the flexible locking arm 342 is forced downward over the tab 312 to extend over the tab to secure the flexible locking arm 342 to the tab. A locking hole in the flexible locking arm 342 catches onto the tab 312 to lock the arm 342 and the lower tray to the chair seat 166. The insertion of tabs 340 into the receiving orifice 310 further secures the lower tray 330 to the chair seat. Preferably, tabs 340 each include a hole 341 which receives an extending member (not shown) inside the receiving orifice 310 to lock the tabs 340 in place as the lower tray 330 is rotated into place. To remove the lower tray 330, the flexible locking arms 342 are simply pulled outward to disengage the locking hole from the tab 312, and the lower tray is lifted off the chair.
FIG. 3 also shows an upper tray 360 which is adapted to be mounted on the restraining structure. The upper tray includes a tray area 362 which is larger than the tray area 332 of the lower tray 330. The larger tray area 362 provides a more convenient surface for use during feeding of the child. The upper tray 360 includes a release button 364 located on the front portion of the upper tray. As explained with regard to FIGS. 4 and 5, the upper tray may be removed from the lower tray by pressing release button 364 or by pulling on a pair of locking members 502.
FIG. 4 shows the bottom view of the lower tray 330, and in particular shows an edge mounting structure 400. FIG. 3 shows the preferred location of the edge mounting structure 400 underneath a protruding portion of the top surface of the arm rest extensions. In the preferred embodiment, the edge mounting structure includes a plurality of indentations underneath the protruding portion of the arm rest extensions 334. Each of the indentations is intended to receive and cooperate with a locking structure located on the upper tray 360 to thereby secure the upper tray to the lower tray.
A bottom view of the upper tray 360 is shown in FIG. 5. In particular, the release button 364 is shown connected to a pair of connection straps 500. The connection straps 500 are preferably of a flexible but rigid plastic material and are used to transmit force from the release button 364 to a locking structure which preferably comprises a pair of locking members 502. The locking members 502 cooperate and engage with the edge mounting structure 400 on the bottom of the arm rest extensions 334 on the lower tray 330 to secure the upper tray 360 to the lower tray 330.
The locking members 502 preferably include a handrelease section 504 and a locking tab structure 506. The locking member 502 is connected to the upper tray 360 to allow the locking member 502 to slide outward and is spring loaded in a locked position (shown in FIG. 5) to engage the edge mounting structure 400. Preferably, a spring (not shown) is mounted internal to the release button 364 to bias the button outwardly toward the edge of the upper tray 360 and the locking members 502 inward toward the center of the upper tray 360. Accordingly, a tension is created in the connection straps 500 to bias the locking member 502 into a locked position.
To install the upper tray 360 onto the lower tray 330, the upper tray is generally positioned over the lower tray, and then lowered until the locking tabs structure 506 engages the edge of the protruding portion of the arm rest extensions 334 of the lower tray. By further lowering the upper tray 360, the locking member is caused to slide in the direction shown by arrow B and the locking tab structure 506 is forced down over the protruding portion. The locking tab structure 506 then snaps into the edge mounting structure 400. As can be seen in FIG. 4, the preferred embodiment includes five indentations which may be engaged by the locking tab structure 506 to provide for a variety of positions of the upper tray 360.
To remove the upper tray 360, the hand-release section 504 may be pulled by reaching along the sides of the upper tray to slide the locking member 502 in the direction shown by arrow B. Similarly, depressing the release button 364 creates a compression force in the connection straps 500 and causes a similar sliding of the locking members 502. Accordingly, the locking tab structure 506 is disengaged from the edge mounting structure 400 to unlock the upper tray 360 which may then be lifted off the lower tray 330.
It will be apparent to those skilled in the art that various modifications and variations can be made in the bracket of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | An improved high chair system includes a leg structure, a child seat, and a lower and an upper tray. The child seat may be reclined, and includes a pair of sloping arm rests which allow the child to be placed close to the dining table and allow easy access to the child. The lower tray may be removably mounted on the sloping arm rests, and the upper tray may be mounted on the lower tray. The upper tray includes a tray area which is larger than that of the lower tray. Advantageous mounting structures for the upper and lower trays are disclosed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to the improved structure of a print head for a dot matrix printer and, in particular, relates to the structure of the print head of a serial printer which can operate with improved high speed operation.
FIG. 1 shows the principle of dot matrix printing in a serial printer. A printer head 100 has seven needles for mosaic or dot matrix printing, and travels along a printing line in the direction of the arrow A. During travelling, needles are selectively driven to strike a paper through an ink ribbon and a desired pattern "A", "B", "C" or "D" is printed. The selection of needles is controlled by the content of an integrated circuit (IC) memory. When the size of a character to be printed is 2.67 mm×2.05 mm, a 7×5 dot matrix is large enough for printing a recognizable character.
One of the prior needle dot print heads for a dot printing process is shown in the U.S. Pat. No. 3,896,918, in which an electro magnetic drive structure for the operation of print needles of a mosaic printing head includes a pivotally mounted armature for each needle arranged along a circular arc. The construction includes a common yoke for all of the electro magnets which comprises two concentric cups or walls forming a single unit with cylindrical cores arranged at equal intervals along a circular arc parallel to the genatrix of the cup and located between the indivudual yoke cups. However, said prior print head has the disadvantages that the power consumption for driving the needles is large, the size of the apparatus is large, and the operational speed of the printer is rather slow. These disadvantages result mainly from the fact that a needle is driven by an electromagnet, and all the printing energy for striking a paper by a needle is given by said electromagnet.
Another print head for a serial dot matrix printer is shown in U.S. Pat. No. 4,225,250, in which a print needle is biased to a first position by a permanent magnet, and balanced at that first position with the force of a spring. When an electromagnet is energized, the flux of the permanent magnet is cancelled, and the needle is moved to a second position by the force of the spring. In this prior art device, the printing energy of the needle for striking the paper is produced by a spring, but not by an electromagnet. Therefore, this printer can be small in size, lower in power consumption, and operate with a relatively high printing speed. However, this printer head has the disadvantage that the printing speed is still not quick enough. In our experiments, this type of print head can operate with a printing speed of 1500 dots per second, but the operational speed of 3000 dots per second is desired.
U.S. Pat. No. 3,955,049 discloses another type of printer head, but the operational speed of this printer is still not quick enough.
The structure of the main part of a typical prior print head is shown in FIGS. 2A and 2B, in which FIG. 2A is a plan view and FIG. 2B is a side view, and only a single needle and the related magnet are shown for the sake of the simplicity of the drawing although an actual print head has a plurality of needles. In these figures, the yoke 5, the permanent magnet 4, the core 6, the electromagnet 3, and the armature 1 form the substantially closed magnetic path, and the armature which has a print needle 7 at the extreme end thereof is supported by the leaf spring 2, the end of which is fixed to the yoke 5 at the point P as shown in the drawings. When the electromagnet 3 is not energized, the armature 1 is attracted to the core 6 by the flux generated by the permanent magnet 4 in the closed magnetic path, and the spring 2 is curved and stores energy. Next, when the electromagnet is energized, the flux generated by the electromagnet cancels the flux of the permanent magnet 4, and thus, the net flux is not sufficient to attract the armature 1. Then, the armature 1 is released and leaves the top of the core 6, and the print needle 7 at the extreme end of the armature 1 is urged to move in the direction of the arrow, to strike the paper and print a dot. However, it should be noted that the armature 1, the spring 2 and the print needle 7 form a bulk moving body with a rotational center near the point P which is the contact point of the leaf spring 2 and the yoke 5, and that the length between the rotational center and the center of gravity τ of said moving body is rather long. In this situation, when the print needle 7 strikes a paper, the moving body still has energy, and the center of gravity of the moving body still moves by inertia, thus the moving body vibrates for a while after each strike action of the print needle. The vibration of the moving body causes the vibration of a print needle.
FIG. 3 shows the vibration of a print needle in a prior art printer head in which the horizontal axis shows time, and the vertical axis shows the displacement of the tip of a print needle. In FIG. 3, a print needle strikes a paper at the time T, but after striking it vibrates as shown in FIG. 3, and when the amplitude of the vibration is large, the needle strikes the paper a second time. This vibration of the print needle increases substantially the contact time of a print needle with a paper, and the energy stored in the spring or the moving body is released very slowly.
Accordingly, the power of impact or striking by a print needle on a paper is rather small as compared with the energy stored in the leaf spring or the kinetic energy of the moving body. The small impact power causes a reduction of the darkness of the printed dot, and a decrease in the printing speed, since the print needle restores slowly because of the small impact force. Further, the vibration of the spring causes the leaf unstable operation of the printer head.
That disadvantage of the vibration might be overcome by using a cross shaped spring instead of a leaf spring, so that the cross shaped spring does not become deformed by the reaction of the impact. However, the cross shaped spring is complicated in structure, as it has two leaf springs crossed with each other, and those two leaf springs must be fixed to the armature and the yoke. Thus, the manufacturing cost of the printer head with a cross shaped spring would be high.
SUMMARY OF THE INVENTION
It is an object, therefore, of the present invention to overcome the disadvantages and limitations of a prior serial printer head for dot matrix printing by providing a new and improved serial printer head.
It is also an object of the present invention to provide a printer head which operates with a higher printing speed than 1500 dots per second.
It is also an object of the present invention to provide a high speed serial printer head which is simple in structure.
The above and other objects are attained by a print head comprising; (a) a cylindrical permanent ring magnet which is axially magnetized; (b) a circular bottom plate covering the bottom of the permanent magnet; (c) a plurality of electromagnets each having a center core and a coil wound around the core positioned on a circle on the bottom plate so as to be surrounded by the permanent magnet; (d) yoke means for providing a substantially closed magnetic path with the permanent magnet, the bottom plate, and each electromagnet; and (e) a plurality of moving bodies equal in number to the number of electromagnets, having at least an elongated armature overlying the core of the related electromagnet and forming a part of the substantially closed magnetic path, a leaf spring supporting the armature which is fixed to the yoke means at the extreme end of the leaf spring, and a print needle mounted substantially perpendicular to the elongated armature at the extreme end thereof. The armature is pulled to the top of the related core in the absence of electric power to the coil to store the strain energy in the leaf spring, and the armature is released upon application of electric power to said coil to cause the print needle strike a paper; A cover plate covers the print head, and has a guide post for guiding the print needles so that the print needles are aligned on a straight line through the slit at the extreme end of the guide post; and each of the moving bodies is rotatably supported at the rotation center so that the armature rotates around the rotation center at one of the edges of the top of the core, and the mass of the moving body is distributed at both the sides of the rotation center.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and attendant advantages of the present invention will be appreciated as the same become better understood by means of the following description and accompanying drawings wherein;
FIG. 1 shows a mosaic pattern for the explanation of the dot matrix printing of the present invention,
FIGS. 2A and 2B show the structure of the prior serial print head when the armature is attracted and released,
FIG. 3 shows the curve showing the relations between the time and the displacement in printing movement of a print needle of the prior art,
FIG. 4 is the explanatory drawing for the explanation of the theoretical principle of the present invention,
FIG. 5A shows the cross sectional view of the serial print head according to the present invention, when the armature is completely attracted,
FIG. 5B is the cross sectional view at the line A-A' of FIG. 5A,
FIG. 5C is the cross sectional view at the line B-B' of FIG. 5A,
FIG. 6A shows a part of the structure of FIGS. 5A,5B, and 5C for the explanation of the printer head of FIGS., 5A, 5B and 5C, when the armature is completely released,
FIG. 6B is the enlarged view of the main part of FIG. 6A,
FIG. 6C is the plane view of a moving body shown in FIG. 6B,
FIG. 7 is another embodiment of the printer head according to the present invention, when the armature is released
FIG. 8 is still another embodiment of the print head according to the present invention,
FIG. 9 is still another embodiment of the print head according to the present invention, when the armature is attracted, and
FIG. 10 is still another embodiment of the printer head according to the present invention, when the armature is released.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The theoretical principle of the present invention is first described in accordance with FIG. 4, in which a rigid moving body B has a center of gravity G, a mass M, and a rotational center or the rotational axis O. When the rigid body B is impacted by a force F at the impact point O', it is rotated around the rotational axis O with an angular velocity (ω), and the reaction force F i applied to the rotational axis O is expressed in the following formula.
F.sub.i =a(ω) ((J/Mh)-x)
where (a) is a constant, J is the moment of inertia of the body B, (h) is the distance between the center of gravity G and the rotational center O, and (x) is the length between the impact point O' (or the contact point of the needle and the armature) and the rotational center O. When F i =O is satisfied, the following formula is satisfied.
x=J/(Mh) (1)
When the formula (1) is satisfied, no reaction force is applied to the rotational axis O, and the body B is not vibrated by the impact force F. Therefore, we call that impact point O', the impact center when there is no reaction force. It should be appreciated that when the formula (1) is satisfied, the mass M is separated by the rotational center O, or the mass M is distributed to both the sides of the rotational center O.
FIG. 5A shows the cross sectional view of the print head according to the present invention, FIG. 5B is the cross sectional view at the line A-A' of FIG. 5A, and FIG. 5C is the cross sectional view at the line B-B' of FIG. 5A. Also, the FIGS. 6A,6B and 6C are the explanatory drawings for the explanation of the operation of the printer head of FIGS. 5A,5B and 5C. In these figures, the reference numeral 22 is a circular bottom plate made of ferro-magnetic material, 4 is a cylindrical ring shaped permanent magnet secured on the bottom plate 22, 11 is a ring shaped first yoke, 10 is a ring shaped ferromagnetic spacer, and 9 is a second yoke with a small center hole. The members 9, 10 and 11 form a yoke means for providing a substantially closed magnetic path with the permanent magnet, the bottom plate, and each of said electromagnets. A plurality of electromagnets each having a core 6 and a coil 3 are positioned along a circle on the bottom plate 22 so as to be surrounded by the permanent magnet 4. A moving body with the armature 1, a print needle 7 fixed at the extreme end of the armature 1, and the leaf spring 8 is fixed to the armature support 12 which is ring shaped and is positioned on the inside wall of the yoke 11 and the spacer 10. The reference numeral 24 is a cover plate made of plastic with a post 24a at the center of the cover plate 24 for guiding the print needles, and an opening or a slit 24b at the top of the post 24a serving as the outlet for the print needles.
It should be appreciated that one end of the print needles 7 are arranged on a circle as shown in FIG. 5B, and the other ends of the same are arranged linearly in the slit as shown in FIG. 5C. A ring shaped stopper 20 is provided at the center on the inside of the cover plate so that the stopper 20 restricts the stroke or the rotation of the armature 1.
The cross section of the core 6 is, preferably, elongated and is positioned radially on the bottom plate 20 so that the longer axis of the elongated cross section is in the radial direction as shown in FIG. 5B.
With the above configuration, it should be noted that a substantially closed magnetic path is provided from the permanent magnet 4, through the yoke 11, the spacer 10, the yoke 9, the armature 1, the core 6, the bottom plate 22, to the permanent magnet 4. Therefore, when the coil 3 of the electromagnet is not energized, the armature 1 is attracted or pulled to the top of the core 6 by the flux in the closed magnetic path induced by the permanent magnet 4, and the spring 8 is curved to store the potential energy or stress and the print needle 7 is withdrawn. FIG. 5A shows the situation in which the armature 1 is attracted to the core 6, and the print needle is withdrawn.
Next, when the coil 3 is energized, the flux induced in the core 6 by the electromagnet with the coil 3 cancels the flux in the core 6 induced by the permanent magnet 4, and the armature 1 is no longer attracted to the core 6. Then, the energy stored in the spring 8 is partially released, and the armature is rotated around the point A which is the external edge of the core 6 (see FIG. 6A and FIG. 6B). With the rotation of the armature 1, the print needle 7 travels outwardly as shown by the arrow X in FIG. 6A, and strikes a paper (not shown) to print a dot. A paper and/or the stopper 20 restricts the stroke or the rotation of the armature 1 so that the armature does not leave contact with the edge A. Therefore, the moving body with the armature 1, the spring 8 and the print needle 7 rotates around the axis A in the direction of the solid arrow P (see FIG. 6A) by releasing the spring 8, and the reaction force by the impact of the paper is applied in the opposite direction shown by the dotted arrow Q. In this case, when the relation of the formula (1) is satisfied, the reaction force by the impact of the paper applied to the rotational axis A is very small, and the spring and/or the moving body does not vibrate when the tip of the print needle 7 impacts upon a paper, and the impact power is very large. When the coil 3 is de-energized, the armature 1 is prompty restored to the original position.
FIG. 6B shows in detail the rotation of the armature 1. When the electromagnet is not energized, and the armature 1 is pulled to the top of the core 6, the armature 1 and the spring 8 are positioned in the dotted line position in FIG. 6B. When electric power is applied to the electromagnet and the armature 1 is released, the moving body rotates in the clockwise direction and is positioned as shown in the solid line position in FIG. 6B.
It should be appreciated in the present invention that the armature 1 does not leave contact with the core 6 even when the armature 1 is released but the armature 1 contacts to the core 6 at the axis A, and that the stress of the spring 8 is only partially released when the armature 1 is released. That is to say, the spring 8 is still stressed a little when the armature 1 is released. In comparison, with the prior art printer head of FIGS. 2A and 2B, a prior art armature 1 in FIG. 2A leaves the core completely when the armature 1 is released, and the stress of the spring is also completely released when the armature is released by applying electric power to the coil. Thus, the prior art armature rotates around the point P of FIG. 2A and the relationship of the formula (1) is not satisfied in the prior art.
In order to assure the above features, the moving body with the armature 1, the spring 8 and the needle 7 has a particular structure. The vertical view of the moving body is apparent from FIG. 6B, and the plan view of the moving body is shown in FIG. 6C. In those figures, 8a is a hole for fixing the moving body to the armature support 12, and the formula (1) is satisfied among the values x, h, G, M and J. Further, the armature 1 is fixed to the spring 8 at a point near the rotational axis A as shown in FIGS. 6B and 6C.
When the formula (1) is satisfied, it should be appreciated that the armature 1 has mass on both sides of the rotational axis A, or the mass of the armature is distributed at both the sides of the rotational center A.
Further, in order to assure that the armature 1 does not leave contact with core 6 at the axis A and the spring 8 is stressed even when released, the spring 8 is fixed to the armature support 12 at the point S' slightly displaced from the point S in the direction to the bottom plate 22, where the point S is the extension of the top surface of the core 6.
FIG. 7 shows another embodiment of the present printer head, in which the rotation center A' is at the inside edge of the core 6, while the rotation center A in FIGS. 5A and 5B is at the outside edge of the core 6. In the embodiment of FIG. 7, the spring 8 is fixed to the yoke at the point S' which is farther than the point S which is the extension of the top of the core 6 from the bottom plate.
FIG. 8 is another embodiment of the present printer head, in which the plate spring 8 is fixed approximately perpendicular to the armature 1, and the spring 8 is fixed to the armature 1 near the rotational center A. In FIG. 8, the reference numeral 13 is a cover made of non-magnetic material which supports the leaf spring 8.
FIG. 9 shows the structure of still another embodiment of the printer head of the present invention. In FIG. 9, the reference numeral 14 is a torsion spring which doubles as the axis of the rotation center of the armature 1, and 15 is the armature support made of ferro-magnetic material for fixing the torsion spring 14 and forms a part of the magnetic path. Of course, the torsion spring 14 is positioned so that the formula (1) is satisfied.
In FIG. 9, when the coil 3 is not energized, the magnetic flux generated by the permanent magnet 4 flows through the yoke 11, the spacer 10, the yoke 9, the armature support 15, the armature 1 and the core 6, and then, the armature 1 is attracted to the core 6. When the armature 1 is rotated by being attracted to the core 6, the torsion spring 14 is twisted and stores some energy. Next, when the coil 3 is energized, the magnetic flux generated by the coil 3 cancels the magnetic flux of the permanent magnet 4, and the armature 1 is not attracted to the core 6 anymore, and the torsion spring 14 is released. Then, the moving body with the print needle 7, the armature 1 and the torsion spring 14 rotates in a counter clockwise direction, and the print needle 7 is pushed to the left as shown by the arrow P of FIG. 7 and prints a dot on a paper. The torsion spring is completely released when the armature 1 is released, while the plate spring in previous embodiments is partially released. When the print needle 7 prints a dot, the print needle takes a reaction force from the paper, however, since the formula (1) is satisfied, the axis takes no reaction force, and the torsion spring 14 is not deformed by the reaction force. Thus, the impact force for striking a dot is relatively large. By de-energizing the coil 3 just after the impact by the print needle 7, the armature 1 is attracted again to the core 6, and the print needle 7 is restored.
It should be noted in FIG. 9 that the core 6 and the armature support 15 are staggered with respect of the center axis of the printer head, and therefore, the armature 1 attracts not only to the core 6 but also to the armature support 15. Therefore, the attraction force of the armature 1 is doubled as compared with the embodiment of FIGS. 5A, 5B and 5C.
FIG. 10 shows the still another embodiment of the printer head according to the present invention, in which the relations between the core 6 and the armature support 15 are reversed as compared with the embodiment of FIG. 9, and the feature and the other structures of the embodiment of FIG. 10 are the same as those of the embodiment of FIG. 9.
As described above in detail, according to the present invention, an armature is supported so that the formula (1) is satisfied, and the mass of the moving body or the armature is distributed on both sides of the rotational center, or the rotational center separates the mass of the moving body. Therefore, the reaction force with impacting a paper by a print needle is not applied to the rotational center, and therefore, the substaitial contact time of the print needle to the paper is decreased, and the impact force by the print needle is increased. Thus, clearer printing is obtained with the improved printing speeds of up to 3000 dots per second. Further, since the present invention utilizes a single spring for each dot, instead of a cross spring which is complicated in structure, the manufacturing cost of the present printer head is cheaper than that having a cross spring.
From the foregoing it will now be apparent that a new and improved printer head has been found. It should be understood of course that the embodiments disclosed are merely illustrative and do not limit the scope of the invention. Reference should be made to the appended claims, therefore, rather than the specification as indicating the scope of the invention. | A high operational speed print head for mosaic printing is provided which has a plurality of print needles positioned on a straight line, each being selectively driven toward a piece of paper through an ink ribbon. The printer head comprises a cylindrical permanent magnet ring magnetized in the axial direction; a circular bottom plate covering the bottom of the permanent magnet; and a plurality of electromagnets each having a center core and a coil wound around the core positioned on a circle on said bottom plate so as to be surrounded by the permanent ring magnet. A yoke provides a closed magnetic path with the permanent ring magnet, the bottom plate and each of the electromagnets. A plurality of moving bodies equal in number to the number of electromagnets are provided, each having at least an elongated armature overlying the core of the related electromagnet and composing a part of said closed magnetic path. A leaf spring supports the armature and is fixed to the yoke, and a print needle is mounted perpendicular to the elongated armature. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to balloon catheters, and more particularly to catheters for use in repairing dissections or tears in the walls of blood vessels.
Several designs of dilatation balloon catheters have been proposed in the prior art, examples of which can be seen in U.S. Pat. Nos. 5,160,321; 5,090,958; 4,787,388; and 4,581,017. Each of those balloon dilatation catheters was designed for the purpose of administering treatments to widen constricted blood flow passages. The term stenosis is used in this regard to refer to a region of a blood vessel which has been narrowed or constricted to such a degree that blood flow is restricted. In severe instances, treatment of the stenosis is required. Treatment of coronary blood vessels by use of the aforenoted prior art dilatation balloon catheters is referred to in the art as percutaneous transluminal coronary angioplasty (PTCA), which procedure is described in various forms in the patents identified above. The term "dilatation catheter", as used herein, will refer to the type of catheter which is principally designed for use in widening constricted blood flow passages, as is done in the PTCA procedure.
One problem associated with PTCA which has been recognized in, for example, U.S. Pat. No. 4,581,017, issued to Sahota, and U.S. Pat. No. 4,787,388, issued to Hofmann, is that, in performing the PTCA procedure, blood flow cannot be completely occluded for extended periods of time, measured in terms of well under one minute, due to the increased probability that serious damage to the patient's heart or other downstream vessels or organs will occur. The Sahota patent presents two approaches to solving this problem, a first of which is to provide a balloon catheter which, even though the inflated balloon completely occludes the blood vessel, i.e., the balloon inflates into contact with the blood vessel around the entire circumference of the blood vessel, blood is permitted to flow from a proximal side of the balloon to the distal (downstream) side of the balloon through a central lumen. The second solution proposed by Sahota, which appears to be conceptually the same as the Hofmann solution, is to design the balloon such that, when the balloon is expended or inflated, it will not completely occlude blood flow, but which will, at the same time, provide sufficient area of balloon contact around the circumference of the blood vessel such that the tissue or other matter creating the constriction in the blood vessel can be compressed against the vessel wall in an effective manner. These designs purport to permit a longer dilatation period to be used when performing the PTCA procedure.
A further balloon catheter design of which the present inventor is aware is disclosed in U.S. Pat. No. 4,762,130, issued to Fogarty et al. This catheter was not designed as a dilatation catheter for use in performing the PTCA procedure, but instead was developed for use in removing blood clots from blood vessels, and also for use as a diagnostic tool carrying diagnostic equipment in a lumen or lumens associated with the catheter. The corkscrew shape of the balloon on this catheter was adopted specifically to avoid the application of diametrically opposed forces on the wall of the blood vessel, so as to minimize the possibility of abrasions and/or perforations occurring in the vessel wall. As such, this balloon catheter would be particularly unsuitable for use in performing the PTCA procedure or for other procedures requiring some amount of diametrically opposed force or other opposing forces to be applied.
It has previously been noted that dissection of the blood vessel is a potential problem in performing the PTCA procedure, and one or more of the aforenoted patents directed to dilatation catheters discuss procedural steps which attempt to minimize the possibility that dissection will occur. None of the above-noted dilatation catheter patents discusses providing a balloon-type catheter having a balloon configuration which is especially well-suited for use in repairing or tacking such dissections.
It is therefore a principal object of the present invention to provide a balloon-type catheter having features making it especially well-suited for repair operations in which blood vessel dissections are tacked back into place along the blood vessel wall.
It is a further principal object of the present invention to provide a balloon-type catheter in which a plurality of balloons are configured in a helical or spiral pattern extending around a central support tube or lumen, whereby tacking of dissections can be achieved while preserving blood flow down the main trunk or blood vessel, and also in side branches extending from the main trunk.
SUMMARY OF THE INVENTION
The present invention provides a balloon catheter configuration whose primary purpose is not the dilatation of constricted portions of blood vessels, but is instead the repair or tacking of dissections in the blood vessel which have been created during the dilatation of the blood vessel in the PTCA procedure, or which have otherwise been created and exist in a blood vessel.
The balloon catheter of the present invention provides a configuration which further permits continued perfusion along the main blood vessel in which the repair operation is being performed, and provides improved protection of flow to side branch blood vessels extending from the main blood vessel under repair, all while the balloons of the catheter are expanded or inflated and are performing their repair function. Both of these features have been determined to be of substantial importance in a balloon catheter whose principal purpose is to repair or tack dissections, in that such repair may require the catheter to be in place with its balloons expanded or inflated for considerable periods of time.
In one or more of the above-noted patents disclosing dilatation catheter devices, the desirability of retaining blood flow down the main blood vessel being treated was recognized, even for relatively short-term occlusion of the blood vessel by the catheter. However, none of those patents discuss the importance of protecting (by preserving) blood flow into side branch vessels. This is likely due to the fact that the dilatation balloon catheters, even when inflated for what would be considered to be extended periods of time in the PTCA procedure, would be inflated and blocking off most, if not all, side branch flow for a time measured in terms of seconds, or at most in terms of a couple of minutes. In contrast, the repair or tacking of a dissection may require on the order of one to several hours or up to approximately one day or more. A continuous inflation of the balloon or balloons on the repair catheter device is important to obtaining the highest quality repair of the blood vessel in the shortest time possible, and thus being able to leave the device in place with the balloon(s) inflated for extended periods of time is an important feature. Preserving the blood flow to the side branches, which is not as critical over lengths of time on the order of several seconds to several minutes, becomes a very important consideration when longer time periods are involved, and is thus a very important consideration in the design of the balloon catheter of the present invention.
The balloon catheter of the present invention has the additional advantage, as respects the use of the catheter in repairing blood vessel dissections, that the balloon elements are arranged such that the balloon elements, when expanded or inflated, present helical or spiral bearing or contact surfaces which will conform to or closely approximate the dissection path of one of the most commonly experienced dissection modes resulting from performing the PTCA process.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the present invention and the attendant advantages will be readily apparent to those having ordinary skill in the art and the invention will be more easily understood from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings, wherein like reference characters represent like parts throughout the several views.
FIG. 1 is an elevational view of the helical balloon catheter of the present invention as disposed and inflated in a blood vessel which is depicted in cross-section.
FIG. 2 is an schematic elevational view of the helical balloon catheter of the present invention.
FIG. 3 is a cross-sectional view of the helical balloon catheter of the present invention taken along section line A--A of FIG. 2.
FIG. 4 is a cross-sectional view of the helical balloon catheter of the present invention taken along section line B--B of FIG. 2.
FIG. 5 is a cross-sectional view of the helical balloon catheter of the present invention taken along section line C--C of FIG. 2.
FIG. 6 is a cross-sectional view of the helical balloon catheter of the present invention taken along section Line D--D of FIG. 1.
FIG. 7 is a perspective cutaway view of a blood vessel schematically illustrating a spiral or helical dissection formed therein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIGS. 1 and 2, the multiple helical balloon catheter is designated by numeral 10. Catheter 10 has a central support tube defining a central lumen 12 adapted to carry therein a guide or advance wire 14 which, as is generally known in the art, is used to facilitate insertion of the catheter to the desired position within the blood vessel. In the present invention, because the device will be used primarily for repair of dissections in blood vessels, the desired position for the catheter in the blood vessel will ordinarily be at the site where the dissection has occurred and/or has been detected.
Disposed at the outer surface of the central lumen 12, and extending therealong in a longitudinal direction, are a plurality of balloon elements 16. The depicted preferred embodiment employs two such balloon elements. The balloon elements 16 are preferably disposed near a distal end 18 of the catheter. The balloon elements 16 are also preferably arranged in a "double helix", wherein two diametrically opposed spiraling or helical balloon elements wind around the central support tube and lumen 12. The balloon elements 16 are preferably bonded to the outer surface of the central lumen with a suitable cement or adhesive 20 (see FIG. 5), along the entire longitudinal extent of the elements, in order to retain the double helical orientation and positioning with respect to the central lumen throughout the insertion and repair procedure. This bonding can be continuous along the longitudinal extent or the adhesive 20 can be applied at substantially regular intervals along the longitudinal extent.
FIGS. 2-5 illustrate preferred constructional features of the double (two balloon segments) helical balloon catheter 10 in one of the preferred embodiments of the present invention. As can be seen in FIG. 2, the central lumen 12 is preferably fluidically isolated from the balloon elements 16 and the means for inflating or expanding the balloon elements. At a proximal end 19 of the balloon subassembly 22, a fluid supply sleeve 24, also referred to as an inflation port, surrounds the central lumen and is coupled to the balloon elements 16 in a fluid-tight connection. The fluid supply sleeve 24 is shown as being coextensive and concentric with the central support tube or lumen 12 and the sleeve extends to the outside of the body. It should be recognized that the fluid supply sleeve (inflation port) and central support tube or lumen 12 can be arranged in many other preferred constructions, one further example of which is an approximately crescent-shaped inflation port extending along the central support tube, wherein the inner portion of the inflation port is integral with, or conforms to and is contact with, the outer surface of the central support tube. The inflation fluid, generally a solution of saline and a contrast agent, is supplied to the balloon elements through this sleeve 24.
The proximal ends of balloon elements 16 are fluidly coupled to and extend toward a distal end of the catheter from the fluid supply sleeve 24. The sleeve acts generally in the nature of an inextensible (under the range of fluid pressures experienced in this service) collar. As can be seen in FIG. 3, the proximal end of each of the balloon elements 16 occupies substantially one-half of the area between central lumen 16 and sleeve 24. When the inflating fluid is transmitted to sleeve 24, the flow of fluid is thus essentially evenly divided into each of the two balloon elements 16. It may be preferred, from a manufacturing standpoint, to produce the sleeve 24 and the balloon elements 16 as an integral unit in an extrusion process.
The balloon elements 16 extend from the fluid supply sleeve 24 in diametrically opposed helical paths toward the distal end of catheter 10. It is to be noted that, for ease of illustration, the balloon elements 16 in FIG. 2 are shown as not being bonded to the central support tube 12, however, as previously noted, these elements 16 are required to be bonded to the central member, at least at intermittent points along their extent.
At a distal end of the balloon elements 16, the ends 28, 30 of the elements are sealed down against the outer surface of the support tube or central lumen 12 (FIGS. 2,4) to ensure that the inflating fluid transmitted into the balloon elements is retained therein to expand or inflate the balloons.
Other means of attaching the balloon elements to the catheter and for supplying fluid into the elements will be readily envisioned by those skilled in the balloon catheter art. FIG. 1, for example, depicts a variation on the construction illustrated in FIGS. 2-5. In FIG. 1, the central support tube or lumen 12 is provided with a fluid supply tube 40 which does not terminate at the proximal end of the balloon elements, as does sleeve 24 in FIG. 2, but further extends concentrically around and along the central lumen for a distance somewhat greater than the longitudinal extent of the balloon elements 16. Supply tube 40 is sealed against the central lumen 12 at its distal end 42, and is coupled at its proximal end 44 to a fluid supply conduit 46 which extends concentrically with along central lumen 12 to a point outside the patient's body, where it is coupled to means for supplying fluid to inflate the balloon elements 16. This fluid supply conduit 46 operates much in the same manner as does sleeve 24 in the FIG. 2 embodiment.
Supply tube 40 has bonded thereto the two balloon elements 16, with the open proximal and distal ends of the balloon elements being connected in a fluid-tight manner to tube 40. Tube 40 is provided with fluid openings 48 at its proximal and distal ends which place the tube 40 in fluid communication with the proximal and distal ends of balloon elements 16. Fluid delivered through conduit 46 enters tube 40 and passes through openings 48 to inflate the balloon elements to the desired pressure. It is to be noted that, in this alternative preferred embodiment, the supply tube 40 is substantially inextensible as compared with the balloon elements 16, such that the inflating fluid supplied inflates the balloon-elements without substantially inflating or expanding the diameter of the tube 40. As with the FIG. 2 embodiment, it may be preferred to form the entire FIG. 1 structure as an integral unit in an extrusion process.
FIG. 5 illustrates, in somewhat schematic form, the cross-section of double helical balloon catheter shown in FIG. 1. The balloon elements 16 are shown in solid lines in their inflated or expanded condition, and are shown in broken lines in their unexpanded condition. The inner wall of the blood vessel is schematically represented by circle 104 in FIG. 5. It can be seen that, at any given point along the longitudinal extent of the balloon elements, a path for the flow of blood through the blood vessel undergoing repair is provided around the outer surfaces of the central support tube or lumen 12, and the expanded or inflated balloon elements 16. The cross-section shown in FIG. 6 is essentially the same as that of FIG. 5, with the exception that the concentric arrangement of the central support tube or lumen 12 and fluid supply tube 40 can be seen in FIG. 6, with the balloon elements being bonded to the outer tube 40.
The use and operation of the double helical balloon catheter device as a blood vessel repair tool will now be described with reference to all figures, but in particular FIGS. 1 and 7. As shown in FIG. 1, the balloon elements 16 are in position and are expanded or inflated, which brings the outer surfaces thereof into contact with the inner wall 104 of the blood vessel 100. It will be readily understood to those of ordinary skill in this field of art that when the catheter is being inserted through the blood vessel to its desired position, the balloon elements 16 will not be inflated (see broken lines, FIG. 5) and the catheter can thus be inserted through the blood vessel without any substantial and potentially damaging scraping or rubbing of the balloons against the walls of the blood vessel. In this respect, techniques for inserting dilatation balloon catheters as have been previously disclosed in the art will generally be applicable to the insertion of the balloon catheter of the present invention, and no detailed discussion of such techniques thus will be included herein.
FIG. 1 illustrates that the balloon catheter 10 of the present invention provides a relatively open blood flow path down the main trunk or blood vessel 100, wherein the blood flowing past the balloon catheter 10 moves through the two approximately helically extending cavities 102 created by the outer surfaces of the balloon elements 16 and central lumen 12, and bordered by the inner wall 104 of the blood vessel 100 (see also FIG. 5).
The method for repairing a dissection at an inner wall of a blood vessel with the device of the present invention involves inserting the catheter 10 into the cardiovascular system of a patient to be treated, with the balloon elements 16 being in their unexpanded or uninflated condition. The distal end of the catheter with guide wire 14 protruding therefrom is first inserted, and the catheter is advanced within the cardiovascular system until the balloon elements are situated in the region within the blood vessel to be repaired where the dissection has been detected. The catheter is then oriented, by rotating the catheter as necessary, such that one of the two balloon elements is positioned immediately adjacent to, but not necessarily touching, the dissection to be repaired. At this point, the balloon elements 16 are expanded or inflated to bring the outer or bearing surface 17 of the balloon element 16 adjacent the dissection into intimate contact with the dissection, which also will bring the other balloon into contact with the wall of the blood vessel at a point substantially diametrically opposite the dissection. The applied pressure is thus focused on the flap 200 (FIG. 7) formed by the dissection, urging the flap 200 back into the vessel wall from which it has become detached.
With the balloon elements thus inflated, blood is permitted to continue flowing past the balloon elements 16 along the main trunk, and into unobstructed side branches in the area at which the balloon elements are disposed. The balloons are left in their inflated or expanded condition for a length of time, most likely on the order of tens of minutes to several hours, which is estimated in advance to be sufficiently long to obtain a substantially permanent tacking of the flap against the inner wall 104 of the blood vessel 100. After that time period has elapsed, the balloon elements are brought back to their uninflated or unexpanded state, and the catheter may then be withdrawn.
It will be readily apparent that various diagnoses may be made with respect to determining whether the tacking of the dissection flap 200 has been successfully accomplished prior to the removal of the catheter, and it is expected that such diagnostic procedures will be so employed.
FIG. 7 illustrates flap 200 resulting from the dissection in the blood vessel wall. The dissection commonly appears in an approximately helical pattern, as is shown. The balloon catheter of the present invention thus is very well suited to repair such dissections, as the helically extending balloon elements 16 can be positioned such that pressure is brought to bear against the flap 200 along most, if not all, of its entire length.
By providing an open helical path for blood to flow along the blood vessel under repair, the device permits the use of balloons which extend along a greater length L (FIG. 2) than the balloons employed on prior dilatation catheters. The preferred length L of the balloons on the present device is on the order of 40 centimeters, as compared with a 10-20 centimeter balloon length in existing commercial dilatation catheters. As can be seen in referring back to FIG. 1, the design of the helical balloon catheter of the present invention preserves blood flow to side branches 106 extending off of the blood vessel under repair, even though the balloons are of a greater length than those previously employed in dilatation catheters.
Other variations on the illustrated preferred embodiments are possible. The balloon elements 16 as shown have a round cross-sectional shape, however, other shapes, such as triangles, may be employed as well. A preferred material of construction for the catheter of the present invention is high density polyethylene, although other materials may be suitable for use. The construction of the device can be modified, if desired, to provide the capability to independently inflate each balloon element. Lastly, while the catheter 10 is shown in the preferred embodiments as having two diametrically opposed balloon elements 16 extending in a helical pattern, it may be possible to employ three or more helically-extending balloon elements which are spaced equidistantly around the central support tube 12.
The foregoing description is provided for illustrative purposes only, and variations and modifications to the depicted and described preferred embodiments may become readily apparent to those of ordinary skill in the art without departing from the spirit and scope of the present invention. Accordingly, the scope of the invention is to be determined by reference to the appended claims. | A balloon catheter device designed to be especially well suited to repair or tack dissections in a blood vessel, and a method for repairing dissections, are provided, wherein the balloon catheter has a central support tube or lumen, and has, near a distal end of the catheter, a plurality of inflatable balloon elements extending along the catheter in helical patterns, with the balloon elements are spaced equidistantly around the central support tube. The catheter thus provides the ability to apply pressure, by way of the inflated balloon elements, to tack a dissection flap against the wall of the blood vessel under repair, while at the same time preserving blood flow in the blood vessel past the catheter as well as in side branch blood vessels extending from the blood vessel under repair. The helical or spiral configuration of the balloon elements provides the device with contact or bearing surfaces which closely approximates the path of spiral dissections which are known to occur in blood vessels. | 0 |
RELATED APPLICATION
[0001] This application is an improvement of U.S. Pat. No. 7,160,042 B2, filed Sep. 11, 2002 and issued Jan. 9, 2007.
FIELD OF THE INVENTION
[0002] This invention relates to a methods of control using only four sensors to control the state of an object in multiple modes or in multiple directions (up, down, left, right, forward, backward, and combinations thereof.
BACKGROUND OF THE INVENTION
[0003] Computers, robots, toys, video games, etc. require two dimensional and three dimensional movement and other types of control means. Keyboards, pointing devices, game controllers, mice, trackballs, joysticks, isopoints, touchpads, touchscreens and a variety of other types of devices have all been used in the past. A compact and faster means of control is needed. Despite the simplification of control devices, it is still difficult for a user with little or no computer or gaming experience to navigate through an application program.
DESCRIPTION OF PRIOR ART
[0004] There are numerous well-known, prior art methods of movement using four sensors independently, the best example would be the cursor control keys on a computer keyboard. With the rapid development of man-machine interfaces for communicating and control, improved control means and methods of movement are becoming increasingly necessary. There is a significant need for a system and method allowing easy navigation through an application program without the need for extensive computer operating or gaming experience. The main objective of the present invention is to overcome all the deficiencies found in all prior art devices using only four sensors for movement and control. Further objects and advantages will become apparent from a consideration of the ensuing description.
SUMMARY OF THE INVENTION
[0005] Preferred embodiments of the present invention use only four binary sensors or four variable controlled sensors to control the state of an object. Briefly described, in one of the preferred embodiments of the present invention, combinations of four sensors control an object, enabling movement of robots, toys, video games, etc.
[0006] Activating the cursor left key moves left.
[0007] Activating the cursor right key moves right.
[0008] Activating the cursor up key moves forward.
[0009] Activating the cursor up key followed by the cursor left key moves forward and leftward, and deactivating the cursor left key continues forward movement.
[0010] Activating the cursor up key followed by the cursor right key moves forward and rightward, and deactivating the cursor right key continues forward movement.
[0011] Activating the cursor down key moves backward.
[0012] Activating the cursor down key followed by the cursor left key moves backward and leftward, and deactivating the cursor left key continues backward movement.
[0013] Activating the cursor down key followed by the cursor right key moves backward and rightward, and deactivating the cursor right key continues backward movement.
[0014] Activating the cursor up key followed by the cursor down key accelerates forward, and deactivating the cursor down key continues forward movement.
[0015] Activating the cursor up key followed by the cursor down key accelerates forward, followed by the cursor left key accelerates forward and leftward, and deactivating the cursor left key continues forward acceleration.
[0016] Activating the cursor up key followed by the cursor down key accelerates forward, followed by the cursor right key accelerates forward and rightward, and deactivating the cursor right key continues forward acceleration.
[0017] Activating the cursor up key followed by the cursor left key and the cursor right key accelerates forward and upward (jump or climb), followed by deactivating the cursor left key and the cursor right key continues forward movement.
[0018] Activating the cursor up key followed by the cursor left key, the cursor down key and the cursor right key accelerates forward and downward (dive), followed by deactivating the cursor left key, the cursor down key and the cursor right key continues forward movement.
[0019] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by simultaneously activating then deactivating the cursor left key and the cursor right key returns an object to its original position (standing).
[0020] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor left key moves leftward in a reduced position (crouching down and moving leftward).
[0021] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor right key moves rightward in a reduced position (crouching down and moving rightward).
[0022] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor up key moves forward in a reduced position (crouching down and moving forward).
[0023] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor up key followed by the cursor left key moves forward and leftward in a reduced position (crouching down and moving forward and leftward).
[0024] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor up key followed by the right key moves forward and rightward in a reduced position (crouching down and moving forward and rightward).
[0025] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor down key moves backward in a reduced position (crouching down and moving backward).
[0026] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor down key followed by the cursor left key moves backward and leftward in a reduced position (crouching down and moving backward and leftward).
[0027] Simultaneously activating then deactivating the cursor left key and the cursor right key reduces an object's position (crouching down), followed by activating the cursor down key followed by the right key moves backward and rightward in a reduced position (crouching down and moving backward and rightward).
[0028] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key returns an object to its original position (standing).
[0029] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor left key moves leftward in a prone position (crawling leftward).
[0030] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor right key moves rightward in a prone position (crawling rightward).
[0031] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor up key moves forward in a prone position (crawling forward).
[0032] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor up key followed by the cursor left key moves forward and leftward in a prone position (crawling forward and leftward).
[0033] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor up key followed by the cursor right key moves forward and rightward in a prone position (crawling forward and rightward).
[0034] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor down key moves backward in a prone position (crawling backward).
[0035] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor down key followed by the cursor left key moves backward and leftward in a prone position (crawling backward and leftward).
[0036] Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key reduces an object to its lowest position (lying down), followed by activating the cursor down key followed by the cursor right key moves backward and rightward in a prone position (crawling backward and rightward).
[0037] Simultaneously activating the cursor left key, the cursor up key and the cursor down key rotates counterclockwise. Simultaneously activating the cursor right key, the cursor up key and the cursor down key rotates clockwise.
[0038] Simultaneously activating the cursor up key and the cursor left key climbs and rolls left. Simultaneously activating the cursor up key and the cursor right key climbs and rolls right.
[0039] Simultaneously activating the cursor down key and the cursor left key dives and rolls left. Simultaneously activating the cursor down key and the cursor right key dives and rolls right.
[0040] Simultaneously activating then deactivating the cursor left key and the cursor right key changes action modes. Simultaneously activating then deactivating the cursor left key, the cursor down key and the cursor right key changes action modes. Simultaneously activating then deactivating the cursor up key and the cursor down key changes action modes.
[0041] Another preferred embodiment of the present invention allows multiple methods of control using only four sensors. Activating a left sensor moves an object to the left and deactivating the left sensor stops leftward movement. Activating a right sensor moves an object to the right and deactivating the right sensor stops rightward movement. Simultaneously activating the left and right sensor exits a cursor movement mode and enters an editing mode. Activating the left sensor backspaces and deactivating the left sensor stops backspacing. Activating the right sensor deletes data and deactivating the right sensor stops deleting data. Simultaneously activating the left and right sensor or activating a fifth sensor exits the editing mode and re-enters the cursor movement mode.
[0042] Activating an up sensor moves an object upward and deactivating the up sensor stops upward movement. Activating a down sensor moves an object downward and deactivating the down sensor stops downward movement. Simultaneously activating the up and down sensor exits a cursor movement mode and enters an editing mode. Activating the up sensor reverses the last undo and deactivating the up sensor stops the reversing of the last undo. Activating the down sensor reverses the last change and deactivating the down sensor stops the reversing of the last change. Simultaneously activating the up and down sensor or activating a fifth sensor exits the editing mode and re-enters the cursor movement mode.
[0043] The system and method of the four sensor control invention, according to the preferred embodiment and alternative preferred embodiments of the invention, are logically developed, relatively easy to learn and very quick to use.
[0044] These and other features of the present invention will be more fully understood by reference to the following drawings and the detailed description of the preferred embodiment.
DESCRIPTION OF THE DRAWINGS
[0045] FIG. 1 . Illustrates one preferred numbered arrangement of a four sensor embodiment found in the disclosed invention.
[0046] FIG. 2 . Illustrates one preferred arrangement of a four sensor embodiment found in the disclosed invention using preferred arrows for direction.
[0047] FIG. 3 . Illustrates one preferred numbered arrangement of a four sensor embodiment found in the disclosed invention.
[0048] FIG. 4 . Illustrates one preferred arrangement of a four sensor embodiment found in the disclosed invention using preferred arrows for direction.
[0049] FIG. 5 . Illustrates one preferred numbered arrangement of a four sensor embodiment found in the disclosed invention.
[0050] FIG. 6 . Illustrates one preferred arrangement of a four sensor embodiment found in the disclosed invention using preferred arrows for direction.
[0051] FIG. 7 . Illustrates one preferred numbered arrangement of a four sensor embodiment found in the disclosed invention.
[0052] FIG. 8 . Illustrates one preferred arrangement of a four sensor embodiment found in the disclosed invention using preferred arrows for direction.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0053] In order to more fully understand the invention, during the course of this description the four sensor control invention and embodiments will be labeled and explained as a first sensor, a second sensor, a third sensor and a fourth sensor, and will be used to easily identify like elements according to the different figures which illustrate the invention. The preferred embodiment of the disclosed invention is shown in FIGS. 2 , 4 , 6 and 8 in the preferred embodiment's simplest binary sensor on/off method form.
[0054] Preferred embodiments of the present invention use only four binary sensors or four variable controlled sensors to control the state of an object.
[0055] In one preferred embodiment of the present invention, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating four sensors individually controls an object in four states of control. Simultaneously activating combinations of four sensors controls an object in more than four states of control. Activating one sensor individually followed by activating combinations of four sensors controls an object in more than four states of control.
[0056] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating four sensors individually to move an object in four different directions. Simultaneously activating combinations of four sensors moves an object in more than four different directions. Activating one sensor individually followed by activating combinations of four sensors moves an object in more than four different directions.
[0057] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating a first sensor, preferably an up sensor, controls an object in a first state, preferably moving forward. Deactivating a first sensor stops control of an object in a first state. Activating a second sensor, preferably a down sensor, controls an object in a second state, preferably moving backward. Deactivating a second sensor stops control of an object in a second state. Activating a third sensor, preferably a left sensor, controls an object in a third state, preferably moving leftward. Deactivating a third sensor stops control of an object in a third state. Activating a fourth sensor, preferably a right sensor, controls an object in a fourth state, preferably moving rightward. Deactivating a fourth sensor stops control of an object in a fourth state.
[0058] Activating a first sensor controls an object in a first state. Simultaneously activating a third sensor with an activated first sensor controls an object in a fifth state, preferably moving forward and rightward. Deactivating a third sensor continues control of an object in a first state. Deactivating a first sensor stops control of an object in a first state. Activating a first sensor controls an object in a first state. Simultaneously activating a fourth sensor with an activated first sensor controls an object in a sixth state, preferably moving forward and rightward. Deactivating a fourth sensor continues control of an object in a first state. Deactivating a first sensor stops control of an object in a first state.
[0059] Activating a second sensor controls an object in a second state. Simultaneously activating a third sensor with an activated second sensor controls an object in a seventh state, preferably backward and leftward. Deactivating a third sensor continues control of an object in a second state. Deactivating a second sensor stops control of an object in a second state. Activating a second sensor controls an object in a second state. Simultaneously activating a fourth sensor with an activated second sensor controls an object in an eighth state, preferably backward and rightward. Deactivating a fourth sensor continues control of an object in a second state. Deactivating a second sensor stops control of an object in a second state.
[0060] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating a first sensor, preferably an up sensor, controls an object in a first state, preferably moving forward. Simultaneously activating a second sensor, preferably a down sensor, with an activated first sensor controls an object in a ninth state, preferably accelerating forward. Deactivating a second sensor stops a control of an object in a ninth state and continue control of an object in a first state. Deactivating a first sensor stops control of an object in a first state.
[0061] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating a first sensor, preferably an up sensor, controls an object in a first state, preferably moving forward. Simultaneously activating a second sensor, preferably a down sensor, with an activated first sensor controls an object in a ninth state, preferably accelerating forward. Simultaneously activating a third sensor, preferably a left sensor, with an activated first sensor and an activated second sensor controls an object in a tenth state, preferably accelerating forward and leftward. Deactivating a third sensor stops a control of an object in a tenth state and continue a control of an object in a ninth state. Simultaneously activating a fourth sensor, preferably a right sensor, with an activated first sensor and an activated second sensor controls an object in an eleventh state, preferably accelerating forward and rightward. Deactivating a fourth sensor stops a control of an object in a eleventh state and continue a control of an object in a ninth state. Deactivating a second sensor stops a control of an object in a ninth state and continue a control of an object in a first state. Deactivating a first sensor stops control of an object in a first state.
[0062] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating a first sensor, preferably an up sensor, controls an object in a first state, preferably moving forward. Simultaneously activating a third sensor, preferably a left sensor, and a fourth sensor, preferably a right sensor, with an activated first sensor controls an object in a twelfth state, preferably accelerating forward and upward. Simultaneously deactivating a third sensor and a fourth sensor continues control of an object in a first state. Deactivating a first sensor stops control of an object in a first state.
[0063] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating a first sensor, preferably an up sensor, controls an object in a first state, preferably moving forward. Simultaneously activating a third sensor, preferably a left sensor, a second sensor, preferably a down sensor, and a fourth sensor, preferably a right sensor, with an activated first sensor controls an object in a thirteenth state, preferably accelerating forward and downward. Simultaneously deactivating a third sensor, a second sensor and a fourth sensor continues control of an object in a first state. Deactivating a first sensor stops control of an object in a first state.
[0064] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, and a fourth sensor, preferably a right sensor, controls an object in a fourteenth state, preferably reducing an object's position. Simultaneously activating and deactivating a third sensor and a fourth sensor exits control of an object in a fourteenth state.
[0065] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, and a fourth sensor, preferably a right sensor, controls an object in a fourteenth state, preferably reducing an object's position. Activating a third sensor controls an object in a fifteenth state, preferably reducing an object's position and moving leftward. Activating a fourth sensor controls an object in a sixteenth state, preferably reducing an object's position and moving rightward. Activating a first sensor, preferably an up sensor, controls an object in a seventeenth state, preferably reducing an object's position and moving forward. Simultaneously activating a third sensor with an activated first sensor controls an object in an eighteenth state. Deactivating a third sensor continues control of an object in a seventeenth state, preferably reducing an object's position and moving forward and leftward. Simultaneously activating a fourth sensor with an activated first sensor controls an object in a nineteenth state, preferably reducing an object's position and moving forward and rightward. Deactivating a third sensor continues control of an object in a seventeenth state. Deactivating a first sensor exits control of an object in a seventeenth state and continues control of an object in a fourteenth state. Simultaneously activating and deactivating a third sensor and a fourth sensor stops control of an object in a fourteenth state.
[0066] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, and a fourth sensor, preferably a right sensor, controls an object in a fourteenth state, preferably reducing an object's position. Activating a second sensor, preferably a down sensor, controls an object in an twentieth state, preferably reducing an object's position and moving backward. Simultaneously activating a third sensor with an activated second sensor controls an object in a twenty-first state, preferably reducing an object's position and moving backward and leftward. Deactivating a third sensor continues control of an object in a twentieth state. Simultaneously activating a fourth sensor with an activated second sensor controls an object in a twenty-second state, preferably reducing an object's position and moving backward and rightward. Deactivating a fourth sensor continues control of an object in a twentieth state. Deactivating a second sensor exits control of an object in a twentieth state and continues control of an object in a fourteenth state. Simultaneously activating and deactivating a third sensor and a fourth sensor stops control of an object in a fourteenth state.
[0067] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, a second sensor, preferably a down sensor, and a fourth sensor, preferably a right sensor, controls an object in a twenty-third state, preferably reducing an object to its lowest position. Simultaneously activating and deactivating a third sensor, a first sensor, preferably an up sensor, and a fourth sensor exits control of an object in a twenty-third state.
[0068] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, a second sensor, preferably a down sensor, and a fourth sensor, preferably a right sensor, controls an object in a twenty-third state, preferably reducing an object to its lowest position. Activating a third sensor, preferably an up sensor, controls an object in a twenty-fourth state, preferably reducing an object to its lowest position and moving leftward. Activating a fourth sensor, preferably an up sensor, controls an object in a twenty-fifth state, preferably reducing an object to its lowest position and moving rightward. Activating a first sensor, preferably an up sensor, controls an object in a twenty-sixth state, preferably reducing an object to its lowest position and moving forward. Simultaneously activating a third sensor with an activated first sensor controls an object in an twenty-seventh state, preferably reducing an object to its lowest position and moving forward and leftward. Deactivating a third sensor continues control of an object in a twenty-sixth state. Simultaneously activating a fourth sensor with an activated first sensor controls an object in a twenty-eighth state, preferably reducing an object to its lowest position and moving forward and rightward. Deactivating a fourth sensor continues control of an object in a twenty-sixth state. Deactivating a first sensor exits control of an object in a twenty-sixth state and continues control of an object in a twenty-third state. Simultaneously activating and deactivating a third sensor, a second sensor and a fourth sensor stops control of an object in a twenty-third state.
[0069] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating and deactivating a third sensor, preferably a left sensor, a second sensor, preferably a down sensor, and a fourth sensor, preferably a right sensor, controls an object in a twenty-third state, preferably reducing an object to its lowest position. Activating a second sensor controls an object in an twenty-ninth state, preferably reducing an object to its lowest position and moving backward. Simultaneously activating a third sensor with an activated second sensor controls an object in a thirtieth state, preferably reducing an object to its lowest position and moving backward and leftward. Deactivating a third sensor continues control of an object in a twenty-ninth state. Simultaneously activating a fourth sensor with an activated second sensor controls an object in a thirty-first state, preferably reducing an object to its lowest position and moving backward and rightward. Deactivating a fourth sensor continues control of an object in a twenty-ninth state. Deactivating a second sensor exits control of an object in a twenty-ninth state and continues control of an object in a twenty-third state. Simultaneously activating and deactivating a third sensor, a second sensor and a fourth sensor stops control of an object in a twenty-third state.
[0070] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a third sensor, preferably a left sensor, a first sensor, preferably an up sensor, and a second sensor, preferably a down sensor, controls an object in a thirty-second state, preferably rotating an object counter-clockwise. Simultaneously deactivating a third sensor, a first sensor and a second sensor stops control of an object in a thirty-second state. Simultaneously activating a fourth sensor, preferably a right sensor, a first sensor and a second sensor controls an object in a thirty-third state, preferably rotating an object clockwise. Simultaneously deactivating a fourth sensor, a first sensor and a second sensor stops control of an object in a thirty-third state.
[0071] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a first sensor, preferably an up sensor, and a third sensor, preferably a left sensor, controls an object in a thirty-fourth state. Deactivating a first sensor and a third sensor stops control of an object in a thirty-fourth state, preferably climbing and rolling an object leftward. Simultaneously activating a first sensor and a fourth sensor, preferably a right sensor, controls an object in a thirty-fifth state. Deactivating a first sensor and a fourth sensor stops control of an object in a thirty-fifth state, preferably climbing and rolling an object rightward.
[0072] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a second sensor, preferably a down sensor, and a third sensor, preferably a left sensor, controls an object in a thirty-sixth state. Deactivating a second sensor and a third sensor stops control of an object in a thirty-sixth state, preferably diving and rolling an object leftward. Simultaneously activating a second sensor and a fourth sensor, preferably a right sensor, controls an object in a thirty-seventh state. Deactivating a second sensor and a fourth sensor stops control of an object in a thirty-seventh state, preferably diving and rolling an object rightward.
[0073] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a first sensor, preferably an up sensor, and a second sensor, preferably a down sensor, controls an object in a thirty-eighth state, preferably changing modes of an object.
[0074] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a third sensor, preferably a left sensor, and a fourth sensor, preferably a right sensor, exits a chordic four sensor first mode, and enters a chordic four sensor second mode, wherein activating combinations of the same four sensors produces secondary control functions. Simultaneously activating a third sensor and a fourth sensor exits the chordic four sensor second mode and re-enters the chordic four sensor first mode.
[0075] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a third sensor, preferably a left sensor, a second sensor, preferably a down sensor, and a fourth sensor, preferably a right sensor, exits a chordic four sensor first mode, and enters a chordic four sensor second mode, wherein activating combinations of the same four sensors produces secondary control functions. Simultaneously activating a third sensor, a second sensor and a fourth sensor exits the chordic four sensor second mode and re-enters the chordic four sensor first mode.
[0076] In another preferred embodiment, combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Simultaneously activating a first sensor, preferably an up sensor, and a second sensor, preferably a down sensor, exits a chordic four sensor first mode, and enters a chordic four sensor second mode, wherein activating combinations of the same four sensors produces secondary control functions. Simultaneously activating a first sensor and a second sensor exits the chordic four sensor second mode and re-enters the chordic four sensor first mode.
[0077] In other preferred embodiments of the present invention, simultaneously activating two sensors, three sensors or four sensors exits a chordic four sensor first mode, and enters a chordic four sensor second mode, wherein activating combinations of the same four sensors produces secondary control functions. Simultaneously activating the same two sensors, three sensors or four sensors exits the chordic four sensor second mode and re-enters the chordic four sensor first mode.
[0078] Another preferred embodiment of the present invention allows multiple methods of control using only four sensors. Independently activating a first sensor, preferably a cursor left sensor, controls an object in a first state, preferably moving an object to the left, and deactivating a first sensor stops control in a first state, stopping leftward movement. Independently activating a second sensor, preferably a cursor right sensor, controls an object in a second state, preferably moving an object to the right, and deactivating a second sensor stops control in a second state, stopping rightward movement. Simultaneously activating a first sensor and a second sensor, followed by simultaneously deactivating a first sensor and a second sensor exits a first mode, preferably a first cursor movement mode, and enters a second mode, preferably a first editing mode. Independently activating a first sensor controls an object in a third state, preferably backspacing, and deactivating a first sensor stops control in a third state, stopping backspacing. Independently activating a second sensor controls an object in a fourth state, preferably deleting data, and deactivating a second sensor stops control in a fourth state, stopping the deletion of data. Simultaneously activating a first sensor and a second sensor, followed by simultaneously deactivating a first sensor and a second sensor or activating a fifth sensor exits a second mode, preferably a first editing mode, and re-enters a preferable first mode, preferably a first cursor movement mode or another preferred mode.
[0079] Independently activating a third sensor, preferably an cursor up sensor, controls an object in a fifth state, preferably moving an object upward, and deactivating a third sensor stops control in a fifth state, stopping upward movement. Independently activating a fourth sensor, preferably a cursor down sensor, controls an object in a sixth state, preferably moving an object downward, and deactivating a fourth sensor stops control in a sixth state, stopping downward movement. Simultaneously activating a third sensor and a fourth sensor, followed by simultaneously deactivating a third sensor and a fourth sensor exits a third mode, preferably a second cursor movement mode, and enters a fourth mode, preferably a second editing mode. Independently activating a third sensor controls an object in a seventh state, preferably reversing the last undo, and deactivating a third sensor stops control in a seventh state, stopping the reversing of the last undo. Independently activating a fourth sensor controls an object in a eighth state, preferably reversing the last change, and deactivating a fourth sensor stops control in a eighth state, stopping the reversing of the last change. Simultaneously activating a third sensor and a fourth sensor, followed by simultaneously deactivating a third sensor and a fourth sensor or activating a fifth sensor exits a fourth mode, preferably a second editing mode, and re-enters a preferable third mode, preferably a second cursor movement mode or another preferred mode.
[0080] In the preferred embodiment of the present invention, when using a computer keyboard or other type of electronic data entry device, activating a sensor or a key produces an active output or a down scan code and deactivating the same sensor or key produces an inactive/null output or an up scan code. Programming an operating system to recognize the active output or down scan codes and the inactive/null output or up scan codes, enables any operating system to make full use of the present invention found in this patent application.
[0081] The presently disclosed four sensor control technology can be used for movement and control on, but not limited to: accelerometers, biometric sensors, biosensors, flex sensors, micro force sensors, motion sensors, movement sensors, optical sensors, piezoelectric force sensors, position sensors, pressure sensors, temperature sensors, touch sensors, touch screen sensors, contact switches, detector switches, dimmer switches, dual motion switches, electromechanical switches, key switches, membrane switches, pushbutton switches, rocker switches, rotary switches, toggle switches, etc.
[0082] The preferred embodiment of the invention uses the preferred cursor left sensor, the preferred cursor right sensor, the preferred cursor up sensor and the preferred cursor down sensor. Other preferred embodiments can use any four sensors a users assigns for control on a computer keyboard or other type of electronic data entry device. The preferred embodiment on a phone keypad uses the star/asterisk [*] key as the preferred left sensor, the pound/number sign [#] key as the preferred right sensor, the eight [8] key as the preferred up sensor and the zero [0] key as the preferred down sensor.
[0083] These and other features of the present invention will be more fully understood by referencing the drawings.
[0084] In summary, the four sensor control invention, according to the preferred embodiment and alternative preferred embodiments of the invention, is logically developed, relatively easy to learn and very quick to use.
[0085] While the invention has been described with reference to the preferred embodiment thereof, it will be appreciated by those of ordinary skill in the art that various modifications can be made to the system and method of the invention without departing from the spirit and scope of the invention as a whole. | Combinations of four sensors control an object, enabling movement for robots, toys, video games, etc. Activating four sensors independently controls an object in four different directions. Multiple methods of using only four sensors to control the state of an object in a two dimensional environment or a three dimensional environment. Methods of using only four sensors to increase or decrease control of an object. Methods of using only four sensors to control the state of an object. Activating four sensors individually, simultaneously or sequentially controls an object in multiple states. Activating at least one sensor followed by or combined with the activation of at least one sensor controls an object in multiple directions. Simultaneously and sequentially activating combinations of four sensors controls an object in more than four different directions. A method of using four sensors to control cursor movement in four directions. Simultaneous activation of the left and right cursor keys exits a cursor movement mode and enters a first editing mode, wherein the left cursor key backspaces and the right cursor key deletes data, and simultaneous activation of the left and right cursor keys exits the first editing mode and re-enters the cursor movement mode or another mode. Simultaneous activation of the up and down cursor keys exits a cursor movement mode and enters a second editing mode, wherein the up cursor key reverses the last undo and the down cursor key reverses the last change, and simultaneous activation of the up and down cursor keys exits the second editing mode and re-enters the cursor movement mode or another mode. Activation of a fifth sensor exits a first or second editing mode and re-enters a cursor movement mode. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a plasma display panel, and more particularly to a method and apparatus for driving a plasma display panel that is adaptive for improving a display quality.
[0003] 2. Description of the Related Art
[0004] Generally, a plasma display panel (PDP) displays a picture by utilizing a visible light emitted from a phosphorus material when an ultraviolet ray generated by a gas discharge excites the phosphorus material. The PDP has an advantage in that it has a thinner thickness and a lighter weight in comparison to the existent cathode ray tube (CRT) and is capable of realizing a high resolution and a large-scale screen.
[0005] The PDP includes an upper substrate and a lower substrate that are opposed to each other with having barrier ribs therebetween. The upper substrate includes first and second electrodes provided in a direction crossing the barrier ribs. The lower substrate includes an address electrode provided in a direction parallel to the barrier ribs, and a dielectric layer for covering the address electrode. A discharge cell is positioned at an intersection among the first and second electrodes and the address electrode.
[0006] Such a PDP drives one frame, which is divided into various sub-fields having a different emission frequency, so as to express gray levels of a picture. Each sub-field is again divided into a reset period for uniformly causing a discharge, an address period for selecting the discharge cell and a sustain period for realizing the gray levels depending on the discharge frequency. For instance, when it is intended to display a picture of 256 gray levels, a frame interval equal to {fraction (1/60)} second (i.e. 16.67 msec) is divided into 8 sub-fields. Each of the 8 sub-fields is divided into an address period and a sustain period. Herein, the reset period and the address period of each sub-field are equal every sub-field, whereas the sustain period are increased at a ratio of 2 n (wherein n=0, 1, 2, 3, 4, 5, 6 and 7) at each sub-field. Since each sub-field has a different sustain period, it is able to express a gray scale of a picture.
[0007] Referring to FIG. 1, a driving apparatus for the PDP includes first and second inverse gamma adjusters 11 A and 11 B, a gain adjuster 12 , an error diffuser 13 , a sub-field mapping unit 14 , a memory 15 , a data aligner 16 and an average picture level (APL) controller 17 .
[0008] Each of the first and second inverse gamma adjusters 11 A and 11 B makes an inverse gamma correction of video data from an input line 10 to thereby linearly convert a brightness value according to a gray level value of the video data.
[0009] The gain adjuster 12 amplifies red, green and blue video data corrected by the first inverse gamma adjuster 11 A by an effective gain to thereby adjust a gain. Further, the gain adjuster 12 adjusts a gain with respect to the red, green and blue video data inputted from the first inverse gamma adjuster 11 A in response to an APL detected by the APL controller 17 .
[0010] The error diffuser 13 diffuses an error component into adjacent cells with respect to data from the gain adjuster 12 to make a fine adjustment of a brightness value. To this end, the error diffuser 13 diffuses an error component into adjacent cells by dividing the data into a positive number part and a decimal fraction part and then multiplying the decimal fraction part by a Floyd-Steinberg coefficient.
[0011] The sub-field mapping unit 14 maps a data from the error diffuser onto a predetermined sub-field pattern to apply the mapped data to the data aligner 16 .
[0012] The data aligner 16 stores the video data inputted from the sub-field mapping unit 14 to the memory 15 and reads out the data stored in the memory 15 to apply the read data to a data driver of the PDP (not shown). The data driver of the PDP includes integrated circuits (IC's) connected to a plurality of address electrodes provided at the PDP to thereby the data inputted from the data aligner 12 to the address electrodes of the PDP.
[0013] The APL controller 17 detects an average brightness per frame of the video data inputted from the second inverse gamma adjuster 11 B, that is, an APL to thereby output an information about the number of sustaining pulses corresponding to the detected APL. The APL detected by the APL controller 17 is inputted to the gain adjuster 12 and the information about the number of sustaining pulses is inputted to a timing controller (not shown). The timing controller controls a circuit generating the sustaining pulses in accordance with an information about the number of sustaining pulses applied from the APL controller 17 to thereby adjust the number of sustaining pulses.
[0014] However, the conventional method and apparatus for driving the PDP has a problem in that contour noise emerges on a moving picture due to an discontinuity of a light generated while sub-fields having a different brightness weighting value are turned on and off in an alignment of the sub-fields. This contour noise allows a brightness at the contour part recognized by the retina tracing a moving object to be darker or brighter than a brightness of the input data when a moving picture is displayed in a certain sub-field alignment.
[0015] However, such a conventional method and apparatus for driving the PDP has a limit in expressing a gray level because it adjusts only a sustaining pulse in accordance with the predetermined sub-field pattern and an average brightness per frame, that is, an APL of the video data. A display quality of the conventional PDP fails to reach a satisfying level due to such a contour noise and a limit in the gray level expression ability.
SUMMARY OF THE INVENTION
[0016] Accordingly, it is an object of the present invention to provide a method and apparatus for driving plasma display panel wherein a gray level expression ability is enhanced and a contour noise is reduced, thereby improving a display quality.
[0017] In order to achieve these and other objects of the invention, a driving apparatus for a plasma display panel according to one aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes an ON data calculator for each sub-field for calculating an ON data for each sub-field to detect a load of said sub-field; and an adjuster for adjusting an arrangement of said sub-field in accordance with said load of the sub-field.
[0018] In the driving apparatus, said weighting value of the sub-field is kept at a predetermined weighing value even after the arrangement of the sub-field was adjusted.
[0019] Said adjuster arranges the sub-field in accordance with a sequence of a sub-field having a higher load.
[0020] Alternatively, said adjuster arranges the sub-field in accordance with a sequence of a sub-field having a lower load.
[0021] A driving apparatus for a plasma display panel according to another aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes a gray level detector for detecting a gray level distribution of a data; and an adjuster for adjusting at least one of the number of sustaining pulses and a sub-field arrangement in accordance with a gray level distribution of said data.
[0022] In the driving apparatus, said adjuster adjusts both the number of sustaining pulses and a sub-field arrangement in accordance with the gray level distribution of said data.
[0023] Said adjuster reduces the number of sustaining pulses when gray levels of said data concentrate on a low gray level.
[0024] Alternatively, said adjuster increases the number of sustaining pulses when gray levels of said data concentrate on a high gray level.
[0025] A driving apparatus for a plasma display panel according to still another aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes a random number generator for optionally generating random numbers; and an adjuster for adjusting at least one of the number of sustaining pulses, a sub-field arrangement and a sub-field alignment in accordance with said random numbers.
[0026] A method of driving a plasma display panel according to still another aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes the steps of calculating an ON data for each sub-field to detect a load of said sub-field; and adjusting an arrangement of said sub-field in accordance with said load of the sub-field.
[0027] In the method, said weighting value of the sub-field is kept at a predetermined weighing value even after the arrangement of the sub-field was adjusted.
[0028] Said step of adjusting the arrangement of said sub-field arranges the sub-field in accordance with a sequence of a sub-field having a higher load.
[0029] Alternatively, said step of adjusting the arrangement of said sub-field arranges the sub-field in accordance with a sequence of a sub-field having a lower load.
[0030] A method of driving a plasma display panel according to still another aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes the steps of detecting a gray level distribution of a data; and adjusting at least one of the number of sustaining pulses and a sub-field arrangement in accordance with a gray level distribution of said data.
[0031] In the method, said step of adjusting said at least one of the number of sustaining pulses and said sub-field arrangement adjusts both the number of sustaining pulses and a sub-field arrangement in accordance with the gray level distribution of said data.
[0032] Said step of adjusting said at least one of the number of sustaining pulses and said sub-field arrangement reduces the number of sustaining pulses when gray levels of said data concentrate on a low gray level.
[0033] Alternatively, said step of adjusting said at least one of the number of sustaining pulses and said sub-field arrangement increases the number of sustaining pulses when gray levels of said data concentrate on a high gray level.
[0034] A method of driving a plasma display panel according to still another aspect of the present invention, in which one frame period is time-divided into a plurality of sub-fields each given by a certain weighting value, includes the steps of optionally generating random numbers; and adjusting at least one of the number of sustaining pulses, a sub-field arrangement and a sub-field alignment in accordance with said random numbers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] These and other objects of the invention will be apparent from the following detailed description of the embodiments of the present invention with reference to the accompanying drawings, in which:
[0036] [0036]FIG. 1 is a block diagram showing a configuration of a conventional plasma display panel driving apparatus;
[0037] [0037]FIG. 2 is a block diagram showing a configuration of a plasma display panel driving apparatus according to a first embodiment of the present invention;
[0038] [0038]FIG. 3 is a graph representing an example of load distribution per sub-field in an input data;
[0039] [0039]FIG. 4 is a detailed block diagram of the sub-field arrangement adjuster shown in FIG. 2;
[0040] [0040]FIG. 5A to FIG. 5C are graphs representing sub-fields re-aligned by the sub-field aligners shown in FIG. 4;
[0041] [0041]FIG. 6 is a block diagram showing a configuration of a plasma display panel driving apparatus according to a second embodiment of the present invention;
[0042] [0042]FIG. 7A to FIG. 7C are graphs representing gray level distributions of various data;
[0043] [0043]FIG. 8 is a detailed block diagram of the sub-field alignment selector shown in FIG. 6; and
[0044] [0044]FIG. 9 is a block diagram showing a configuration of a plasma display panel driving apparatus according to a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0045] Referring to FIG. 2, a PDP driving apparatus according to a first embodiment of the present invention includes first and second inverse gamma adjusters 21 A and 21 B, a gain adjuster 22 , an error diffuser 23 , a sub-field mapping unit 24 , a memory 25 , a data aligner 26 , an average picture level (APL) controller 27 , and an ON data calculator 1 for each sub-field and a sub-field arrangement adjuster 2 that are connected between the sub-field mapping unit 24 and the data aligner 26 .
[0046] Each of the first and second inverse gamma adjusters 21 A and 21 B makes an inverse gamma correction of video data from an input line 20 to thereby linearly convert a brightness value according to a gray level value of the video data.
[0047] The gain adjuster 22 amplifies red, green and blue video data corrected by the first inverse gamma adjuster 21 A by an effective gain to thereby adjust a gain. Further, the gain adjuster 22 adjusts a gain with respect to the red, green and blue video data inputted from the first inverse gamma adjuster 21 A in response to an APL detected by the APL controller 17 .
[0048] The error diffuser 23 diffuses an error component into adjacent cells with respect to data from the gain adjuster 22 to make a fine adjustment of a brightness value.
[0049] The sub-field mapping unit 24 maps a data from the error diffuser 23 onto a predetermined sub-field pattern to apply the mapped data to the ON data calculator 1 for each sub-field.
[0050] The ON data calculator 1 for each sub-field calculates ON data for each sub-field of data inputted from the sub-field mapping unit 24 to thereby calculates a load for each sub-field. FIG. 3 represents an example of an ON data amount for each sub-field, that is, a load for each sub-field calculated by the ON data calculator 1 for each sub-field.
[0051] The sub-field arrangement adjuster 2 re-arranges the sub-fields while keeping a brightness weighting value for each sub-field in accordance with ON data information inputted from the ON data calculator 1 for each sub-field.
[0052] The data aligner 26 stores the video data inputted from the sub-field arrangement adjuster 2 to the memory 25 and reads out the data stored in the memory 25 to apply the read data to a data driver 3 of the PDP. The data driver 3 of the PDP includes integrated circuits (IC's) connected to a plurality of address electrodes provided at the PDP to thereby the data inputted from the data aligner 26 to the address electrodes of the PDP.
[0053] The APL controller 27 detects an average brightness per frame, that is, an APL of the video data inputted from the second inverse gamma adjuster 21 B, to thereby output an information about the number of sustaining pulses corresponding to the detected APL. The APL detected by the APL controller 27 is inputted to the gain adjuster 22 , and the information about the number of sustaining pulses is inputted to a timing controller (not shown). The timing controller controls a circuit generating the sustaining pulses in accordance with an information about the number of sustaining pulses applied from the APL controller 27 to thereby adjust the number of sustaining pulses.
[0054] An function and operation of the sub-field arrangement adjuster 2 will be described with reference to FIG. 4 to FIG. 5C below.
[0055] Referring to FIG. 4, the sub-field arrangement adjuster 2 includes n sub-field aligners 41 to 4 n (wherein, n is an integer) for re-arranging sub-fields under a different reference.
[0056] The first sub-field aligner 41 re-arranges the sub-fields in accordance with a sequence having a high sub-field load while keeping a brightness weighting value for each sub-field. If it is assumed that a load for each sub-field calculated by the ON data calculator 1 for each sub-field should be as shown in FIG. 3, then the first sub-field aligner 41 primarily arranges a data for the third sub-field SF 3 having the highest load and then arranges the fifth sub-field SF 5 , the seventh sub-field SF 7 , the second sub-field SF 2 , the sixth sub-field SF 6 , the first sub-field SF 1 , the fourth sub-field SF 4 and the eighth sub-field SF 8 in accordance with a sequence having a higher load as shown in FIG. 5A.
[0057] The second sub-field aligner 42 re-arranges the sub-fields in accordance with a sequence having a low sub-field load while keeping a brightness weighting value for each sub-field. If it is assumed that a load for each sub-field calculated by the ON data calculator 1 for each sub-field should be as shown in FIG. 3, then the second sub-field aligner 42 primarily arranges a data for the eighth sub-field SF 8 having the lowest load and then arranges the fourth sub-field SF 4 , the first sub-field SF 1 , the sixth sub-field SF 6 , the second sub-field SF 2 , the seventh sub-field SF 7 , the fifth sub-field SF 5 and the third sub-field SF 3 in accordance with a sequence having a lower load as shown in FIG. 5B.
[0058] The third sub-field aligner 43 re-arranges a portion of sub-fields in accordance with a sequence having a high sub-field load and re-arranges the remaining sub-fields in accordance with a sequence having a low sub-field load while keeping a brightness weighting value for each sub-field. If it is assumed that a load for each sub-field calculated by the ON data calculator 1 for each sub-field should be as shown in FIG. 3, then the third sub-field aligner 43 primarily arranges a data for the third sub-field SF 3 having the highest load and then the eighth sub-field SF 8 having the lowest load, and thereafter arranges the fifth sub-field SF 5 , the fourth sub-field SF 4 , the seventh sub-field SF 7 , the first sub-field SF 1 , the second sub-field SF 2 and the sixth sub-field SF 6 .
[0059] Output data of the sub-field aligners 41 to 4 n may be selected regularly as output data of a specific sub-field aligner or as output data of at least two sub-field aligners arranged periodically or non-periodically. For instance, output data of the first sub-field aligner 41 may be applied to the data aligner 26 . Alternatively, output data of the first sub-field aligner 41 may be primarily applied to the data aligner 26 and then output data of the second sub-field aligner 42 may be applied to the data aligner 26 .
[0060] If the sub-fields are arranged in a sequence having a higher load or a lower load in the above-mentioned manner, then each discharge cell is continuously emitted and hence an emission frequency between the continuous sub-fields does not have a large difference. Accordingly, a contour noise does almost not emerge on a moving picture.
[0061] [0061]FIG. 6 shows a PDP driving apparatus according to a second embodiment of the present invention.
[0062] Referring to FIG. 6, the PDP driving apparatus includes first and second inverse gamma adjusters 61 A and 61 B, a gain adjuster 62 , an error diffuser 63 , a sub-field mapping unit 64 , a memory 65 , a data aligner 66 , an average picture level (APL) controller 67 , a gray level calculator 7 for detecting a gray level distribution of an input data, a sustaining pulse number adjuster 4 for adjusting the number of sustaining pulses in accordance with the gray level distribution, and a sub-field arrangement selector 5 for selecting a sub-field arrangement in accordance with the gray level distribution.
[0063] The first and second inverse gamma adjusters 61 A and 61 B, the gain adjuster 62 and the error diffuser 63 is substantially identical to those of the above-mentioned first embodiment.
[0064] The APL controller 67 detects an average brightness per frame, that is, an APL of the video data inputted from the second inverse gamma adjuster 61 B, to thereby output an information about the number of sustaining pulses corresponding to the detected APL. The APL detected by the APL controller 67 is inputted to the gain adjuster 62 , and the number of sustaining pulses is inputted to the sustaining pulse number adjuster 4 .
[0065] The gray level detector 7 obtains the entire distribution, that is, a histogram of each gray level for every one frame with respect to a data from the input line 60 . Further, the gray level detector 7 applies the detected gray level distribution to the sustaining pulse number adjuster 4 and the sub-field arrangement selector 5 . Alternatively, the gray level detector 7 divides a gray level distribution GR of data into predetermined regions for its detection. For instance, the gray level detector 7 can divide the gray level distribution GR into a first region between 0 through 32, a second region between 33 through 64, a third region between 65 through 96, a fourth region between 97 through 128, a fifth region between 161 through 192, a sixth region between 193 through 224 and a sixth region between 225 through 256 for its detection.
[0066] The sustaining pulse number adjuster 4 adjusts the number of sustaining pulses inputted from the APL controller 42 in accordance with the gray level distribution GR. If data having a low gray level are more than data having the other gray levels in the gray level distribution GR, then the sustaining pulse number adjuster 4 reduces the number of sustaining pulses to less than the predetermined reference value to thereby control a dark picture such that it becomes darker. On the other hand, if data having a high gray level are more than data having the other gray levels in the gray level distribution GR, then the sustaining pulse number adjuster 4 increases the number of sustaining pulses to more than the predetermined reference value to thereby control a bright picture such that it becomes brighter.
[0067] The sub-field arrangement selector 5 has been stored, in advance, with a sub-field arrangement in which a low gray level expression is emphasized, a sub-field arrangement in which a middle gray level expression is emphasized, a sub-field arrangement in which a high gray level expression is emphasized and a sub-field arrangement on which a contour noise does almost not emerge, etc. The sub-field arrangement selector 5 selects a specific sub-field arrangement from a plurality of predetermined sub-field arrangements in accordance with the gray level distribution GR from the gray level detector 7 .
TABLE 1 Arrangement 1 1 2 4 8 16 32 64 128 Arrangement 2 1 2 4 8 16 128 32 64 Arrangement 3 1 2 4 8 16 32 64 64 64
[0068] If a portion of the sub-field arrangements stored in the sub-field arrangement selector 5 is as the above table and a data having a gray level in which a contour noise may emerge is inputted, then the sub-field selector 5 selects a sub-field arrangement ‘Arrangement 1’ or a sub-field arrangement ‘Arrangement 2’. If a data having a data value changing from 127 into 128 is inputted, then the sub-field arrangement selector 5 selects ‘Arrangement 2’ to reduce a contour noise. Furthermore, if a data having a data value changing from 32 into 64 is inputted, then the sub-field arrangement selector 5 selects ‘Arrangement 3’ to reduce a contour noise.
[0069] The sub-field mapping unit 64 maps a data from the error diffuser 63 onto the sub-field arrangement selected by the sub-field arrangement selector 5 to apply the mapped data to the data aligner 66 .
[0070] The data aligner 66 stores the video data inputted from the sub-field mapping unit 64 to the memory 65 and reads out the data stored in the memory 65 to apply the read data to a data driver 68 of the PDP. The data driver 68 of the PDP includes integrated circuits (IC's) connected to a plurality of address electrodes provided at the PDP to thereby the data inputted from the data aligner 66 to the address electrodes of the PDP.
[0071] [0071]FIG. 7A to FIG. 7C represent examples of gray distribution of an input data.
[0072] [0072]FIG. 7A illustrates a gray level distribution when there are many data having a middle gray level of data for one frame; FIG. 7B illustrates a gray level distribution when there are many data having a low gray level of data for one frame; and FIG. 7C illustrates a gray level distribution when there are many data having a middle gray level of data for one frame. When such data is inputted, the PDP driving method and apparatus detects a gray level distribution of a data and differentiates the number of sustaining pulses and a sub-field arrangement in accordance with the detected gray level distribution, thereby adjusting the number of sustaining pulse and the sub-field arrangement. Accordingly, it becomes possible to enhance a gray level expression ability and reduce a contour noise.
[0073] [0073]FIG. 8 shows the sub-field arrangement selector 5 in detail.
[0074] Referring to FIG. 8, the sub-field arrangement selector 5 includes a memory 82 stored with n sub-field arrangements, and a selector 83 for controlling the memory 82 .
[0075] The selector 83 selects a specific sub-field arrangement from the n sub-field arrangements stored in the memory 82 in accordance with a gray level distribution from the gray level detector 7 . Further, the selector 83 applies the selected sub-field arrangement to the sub-field mapping unit 64 .
[0076] [0076]FIG. 9 shows a PDP driving apparatus according to a third embodiment of the present invention.
[0077] Referring to FIG. 9, the PDP driving apparatus includes first and second inverse gamma adjusters 81 A and 81 B, a gain adjuster 82 , an error diffuser 83 , a sub-field mapping unit 84 , a memory 85 , a data aligner 86 , an average picture level (APL) controller 87 , a random number generator 8 for generating random numbers, and a sub-field arrangement/alignment adjuster 9 connected between the random number generator 8 and the sub-field mapping unit 84 .
[0078] Each of the first and second inverse gamma adjusters 81 A and 81 B makes an inverse gamma correction of video data from an input line 80 to thereby linearly convert a brightness value according to a gray level value of the video data.
[0079] The gain adjuster 82 amplifies red, green and blue video data corrected by the first inverse gamma adjuster 81 A by an effective gain to thereby adjust a gain. Further, the gain adjuster 82 adjusts a gain with respect to the red, green and blue video data inputted from the first inverse gamma adjuster 81 A in response to an APL detected by the APL controller 87 .
[0080] The error diffuser 83 diffuses an error component into adjacent cells with respect to data from the gain adjuster 22 to make a fine adjustment of a brightness value.
[0081] The sub-field mapping unit 84 maps a data from the error diffuser 83 onto a sub-field pattern selected by the sub-field arrangement/alignment adjuster 9 .
[0082] The data aligner 86 stores the video data inputted from the sub-field mapping unit 84 to the memory 85 and reads out the data stored in the memory 85 to apply the read data to a data driver 88 of the PDP. The data driver 88 of the PDP includes integrated circuits (IC's) connected to a plurality of address electrodes provided at the PDP to thereby the data inputted from the data aligner 86 to the address electrodes of the PDP.
[0083] The APL controller 87 detects an average brightness per frame, that is, an APL of the video data inputted from the second inverse gamma adjuster 81 B, to thereby output an information about the number of sustaining pulses corresponding to the detected APL. The APL detected by the APL controller 87 is inputted to the gain adjuster 82 , and the information about the number of sustaining pulses is inputted to a timing controller (not shown). The timing controller controls a circuit generating the sustaining pulses in accordance with an information about the number of sustaining pulses applied from the APL controller 87 to thereby adjust the number of sustaining pulses.
[0084] The random number generator 8 generates a certain of random numbers RD and applies the random numbers RD to the sub-field arrangement/alignment adjuster 8 .
[0085] The sub-field arrangement/alignment adjuster 9 is stored with a plurality of sub-field arrangements in which a sub-field arrangement, the number of sub-fields and a weighting value of the sub-fields are different from each other. The sub-field arrangement/alignment adjuster 9 selects a sub-field arrangement corresponding to random numbers RD from the random number generator 8 to apply it to the sub-field mapping unit 84 .
[0086] As a result, the PDP driving method and apparatus according to the third embodiment of the present invention optionally changes a sub-field arrangement, a weighting value of sub-fields or the number of sub-fields, thereby minimizing a contour noise that may emerge at a certain sub-field arrangement.
[0087] As described above, the PDP driving method and apparatus according to the present invention re-arranges a data in accordance with a load sequence of the sub-fields, or differentiates a sub-field arrangement in accordance with a gray level distribution of the data or optionally differentiates a sub-field arrangement. Accordingly, the PDP driving method and apparatus according to the present invention can enhance a gray level expression ability and can minimize a contour noise, thereby improving a display quality.
[0088] Although the present invention has been explained by the embodiments shown in the drawings described above, it should be understood to the ordinary skilled person in the art that the invention is not limited to the embodiments, but rather that various changes or modifications thereof are possible without departing from the spirit of the invention. Accordingly, the scope of the invention shall be determined only by the appended claims and their equivalents. | A method and apparatus for driving a plasma display panel that is adaptive for improving a picture quality. In the method and apparatus, an ON data for each sub-field is calculated to detect a load of said sub-field. An arrangement of the sub-field is adjusted in accordance with said load of the sub-field. | 6 |
TECHNICAL FIELD
The present disclosure relates generally to fluid level monitoring and, more particularly, to an acoustic fluid level monitoring system for cryogenic containers.
BACKGROUND
Cryogenic containers have unique insulation requirements and are commonly used for very low temperature storage. Some vehicle fuel cells use cryogenic containers to store fuel in fluid form at very low temperatures. Measuring the fluid level inside of a cryogenic container can be difficult as both the containers and their contents pose special challenges.
SUMMARY
One embodiment includes a cryogenic container and an acoustic sensor positioned to sense the resonant frequency of the container and any liquid contents therein.
Another embodiment includes an inner container defining a storage area in which a fluid is stored, an outer container provided outside of the inner container, an insulation layer provided between the inner container and the outer container, and an acoustic sensor attached to the cryogenic container outside of the storage area.
Yet another embodiment includes a method of measuring the fluid level of a cryogenic container by measuring an acoustic resonant frequency of a cryogenic container, and correlating the acoustic resonant frequency of the cryogenic container to a fluid level inside the storage area.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a product according to one embodiment of the invention;
FIG. 2 illustrates a product according to another embodiment of the invention;
FIG. 3 illustrates a product according to another embodiment of the invention;
FIG. 4 illustrates a product according to another embodiment of the invention; and
FIG. 5 illustrates a product according to another embodiment of the invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The following description of embodiments is merely exemplary in nature and is not intended to limit the invention, its application, or uses.
Cryogenic containers are commonly used for low temperature storage, fore example, generally below −150° C., −238° F., or 123 K. Many include inner and outer containers separated by insulation. This design limits heat transfer to the storage area inside the inner container. Cryogenic containers are typically designed to have exceptionally efficient insulation to maintain low temperatures without requiring complex refrigeration equipment. This is partially accomplished by limiting the number of potential heat paths to the storage area.
A potential heat path can be any wire, pipe, tube, or the like that creates a path between the storage area and the outer container. Any such path can potentially allow heat to travel to the storage area and reduce the cryogenic container's efficiency. A cryogenic container may be more efficient by limiting the number of potential heat paths, so it can maintain low temperature storage for longer periods of time without refrigeration.
Cryogenic containers are often used for storing liquefied gases, such as hydrogen, nitrogen, helium, and others. Certain liquefied gasses can be used in fuel cells and require cryogenic containers for storage. Some fuel cells are used in automotive applications that require in-vehicle cryogenic containers for fuel storage. In such applications it may be necessary and challenging to monitor the fuel or fluid level inside the cryogenic container.
FIG. 1 illustrates one embodiment of an acoustic fluid level monitoring system 10 . System 10 may generally include a cryogenic container 20 , an acoustic sensor 40 , and a signal processor 50 . Cryogenic container 20 may include an inner container 22 , an outer container 24 , and an insulation layer 26 separating inner and outer containers 22 , 24 . Inner container 22 generally defines storage area 28 that houses the stored material. Cryogenic container 20 , as shown, is generally known in the art so the following description simply provides a brief overview of one such cryogenic container. However, other containers not shown here could employ the disclosed system and method as well.
A substance, such as hydrogen, may be stored in storage area 28 in a fluid state. The substance is generally stored at very low temperatures and may also be pressurized. Generally, inner container 22 provides a barrier that prevents the stored substance from migrating from within storage area 28 , whether the substance is a fluid, gas, or mixture. Insulation layer 26 generally provides efficient thermal insulation between inner and outer containers 22 , 24 . Insulation layer 26 may also provide structural support, as additional structural support may be required when storage area 28 is pressurized, for example. Outer container 24 generally provides additional structural support and protects insulation layer 26 and inner container 22 from external factors, such as the environment.
Generally, the substance stored in storage area 28 may be in both fluid and gaseous forms. The fluid is typically removed from storage area 28 through a suitable valve and pipe assembly (not shown). As the fluid is removed from storage area 28 , the remaining volume is occupied with the substance in gaseous form. For example, liquid hydrogen may be stored in storage area 28 . As the liquid hydrogen is removed from storage area 28 , gaseous hydrogen generally fills the remaining volume.
Monitoring the fluid level within storage area 28 becomes increasingly important as cryogenic containers are used in mobile applications, such as for vehicle fuel cells. Since the stored substance is used as a fuel for powering the vehicle, the substance must be periodically replaced. Monitoring the fluid level aids in the replacement process.
As shown in FIG. 1 , system 10 utilizes acoustic sensor 40 to monitor the fluid level within storage area 28 by sensing the acoustic resonant frequency of cryogenic container 20 . To determine the fluid level, a first acoustic resonant frequency F 1 of cryogenic container 20 is measured while storage area 28 is empty. A fluid substance is added to storage area 28 , thereby changing the acoustic resonant frequency of cryogenic container 20 . A second acoustic resonance frequency F 2 can then be measured using acoustic sensor 40 . The difference between F 1 and F 2 can then be calculated and correlated to the fluid level within storage area 28 . As the fluid level changes within storage area 28 , the acoustic resonant frequency will also change. Stated another way, fluid within storage area 28 changes the frequency of vibration for cryogenic container 20 .
Acoustic sensor 40 measures the acoustic resonant frequency of cryogenic container 20 by sensing vibrations. Acoustic sensor 40 may be a piezo vibration sensor, a piezoelectric diaphragm, a laser vibrometer, an electromagnetic converter, or a semiconductor. Generally, signal processor 50 receives electrical or electromagnetic signals from acoustic sensor 40 , and process those signals to determine the fluid level within storage area 28 . Acoustic sensor 40 may use only one device for sensing the vibration of cryogenic container 20 , or may use several devices located in different areas.
Turning now in more detail to FIGS. 1-4 , acoustic sensor 40 may be placed in various locations. As shown, inner container 22 includes interior surface 30 and exterior surface 32 , and outer container 24 includes interior surface 34 and exterior surface 36 . In one embodiment shown in FIG. 1 , acoustic sensor 40 is attached to exterior surface 36 of outer container 24 . FIGS. 2-4 are sectional views taken along line 3 - 3 of FIG. 1 . FIG. 2 illustrates another embodiment where acoustic sensor 40 may be located on interior surface 34 of outer container 24 . FIG. 3 illustrates another embodiment where acoustic sensor 40 may be located within insulation layer 26 . And FIG. 4 illustrates yet another embodiment where acoustic sensor 40 may be located on exterior surface 32 of inner container 22 . Other embodiments are also envisioned, such as locating acoustic sensor 40 on interior surface 30 of inner container 22 , thereby locating acoustic sensor 40 within storage area 28 . Regardless of its location, acoustic sensor 40 communicates with signal processor 50 .
Signal processor 50 may be any suitable device for receiving and processing signals from acoustic sensor 40 . And signal processor 50 may be connected to acoustic sensor 40 by wire 52 . They may also communicate by various wireless means using technologies such as radio frequency (RF), infrared (IR), or electromagnetism (EM), just to name a few. Signal processor 50 may be a digital computer with a digital signal processor (DSP) for receiving and analyzing signals from acoustic sensor 40 . Signal processor 50 may also have electronic memory and software for calculating the fluid level within storage area 28 . In one embodiment, signal processor 50 calculates a fluid level within storage area 28 after receiving a signal from acoustic sensor 40 . The fluid level may be calculated by way of a lookup table, calculation, or other methods known to those skilled in the art. The fluid level can be calculated using an initial acoustic resonant frequency of cryogenic container F 1 taken when storage area 28 is empty, and comparing F 1 to the current acoustic resonant frequency F 2 . Signal processor 50 may also receive other data, such as temperature and pressure of storage area 28 , and use such data to further refine the fluid level calculation based on the change in acoustic resonant frequency.
To measure the acoustic resonant frequency, an impulse may be generated to stimulate cryogenic container 20 . An impulse generally may be anything that stimulates oscillation or vibration of cryogenic container 20 . An impulse can be generated by impulse generator 42 or by natural phenomenon. For example, in an automotive fuel cell application when a fluid substance is stored within storage area 28 , the impulse may result from fluid sloshing, a natural phenomenon. The stored fluid sloshes as the vehicle accelerates, decelerates, or turns. The sloshing fluid within storage area 28 causes vibrations, allowing acoustic sensor 40 to then measure the acoustic resonant frequency of cryogenic container 20 .
In another embodiment, impulse generator 42 stimulates cryogenic container 20 . Impulse generator 42 may be an actuator, a piezoelectric device, an electromagnetic converter, a semiconductor, or mechanical sound spring. In one embodiment, acoustic sensor 40 and impulse generator 42 are one device serving both functions. For example, a piezoelectric device can be driven by an external power source to produce vibrations, causing cryogenic container 20 to vibrate. The same piezoelectric device can then be used in a passive mode to measure the acoustic resonant frequency of cryogenic container 20 . Alternatively, acoustic sensor 40 and impulse generator 42 may be separate devices located in various locations throughout cryogenic container 20 .
One embodiment may include a vehicle 100 , such as an automobile, truck, bus, boat, military vehicle, etc. Vehicle 100 , as shown in FIG. 5 , may include a fuel cell 102 and a cryogenic container 20 for supplying liquid hydrogen to fuel cell 102 . An acoustic sensor 40 may be provided to sense the resonant frequency of container 20 . Acoustic sensor 40 is capable of communicating the sensed resonant frequency to signal processor 50 . Signal processor 50 processes the signal received from acoustic sensor 40 and communicates with a tank level communication means 104 , which then communicates the level of liquid hydrogen in container 20 . Embodiments of tank level communication means 104 include, but are not limited to, a gauge, a digital display, a speaker, an audiovisual device, or another sensor that communicates with a vehicle computer or other vehicle hardware component. Tank level communication means 104 may communicate to a vehicle occupant, a vehicle system, or to a remote system via a wireless communication system.
The above description of certain embodiments of the invention is merely exemplary in nature and, thus, variations, modifications and/or substitutions thereof are not to be regarded as a departure from the spirit and scope of the invention. Tank assemblies embodying the present invention may have none, some, or all of the noted features and/or advantages. That certain features are shared among the presently preferred embodiments set forth herein should not be constructed to mean that all embodiments of the present invention must have such features. | A product including a cryogenic container and an acoustic sensor positioned to sense the resonant frequency of the container and any liquid contents therein. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to Cu-based bulk amorphous matrix composite materials and a production method thereof, and more particularly to Cu-based bulk amorphous matrix composite materials containing high fusion point elements, which considerably increase the elongation rate while minimizing the reduction of strength of the bulk amorphous materials through adding high fusion point elements, Ta and/or W, so as to control abrupt fracture behaviors of the amorphous materials, and to a production method thereof.
[0003] That is to say, the present invention relates to Cu-based bulk amorphous matrix composite materials containing high fusion point elements, in which a certain ratio of Ta or W solid solution is dispersed in a Cu-based matrix with above 90% of amorphous volumetric ratio, providing excellent mechanical properties such as strength, elongation rate and so forth, and to a production method thereof.
[0004] 2. Description of the Prior Art
[0005] Recently, as in pursuing of scale-down, lightening and multifunctioning of machine parts, it has been requiring a multi functional structural metallic materials improving mechanical properties and functionibility two or more times over the existing structural materials. Bulk type amorphous metallic materials are the innovative materials to satisfy such requirements of times, so that they have been world widely studying actively. Bulk type amorphous materials in which their atomic structures becomes to be amorphous are regarded as the next-generation structural metallic materials exceeding limits of physical properties of the existing metallic materials and are estimated as strategic metallic materials the new industry of the future requires after they had been initially reported by Caltech of USA in 1993.
[0006] Among amorphous materials, zirconium-based alloy has been commercially developing as materials for sporting goods and the military. However, since the element, zirconium has a specialty in light of resources, it has been now developing various kinds of commercial alloy amorphous materials. Representative one of the commercial metallic materials, Cu-based amorphous materials have characteristics similar to the other alloy system and have a high value in economic aspects as well.
[0007] Johnson et al., USA, reported Cu-based amorphous alloy containing about 40˜60 atomic weight %, and registered Patent claiming compositions including the above composition. (Refer to a document, JOURNAL OF APPLIED PHYSICS, VOL. 83, 1998, p7993, Johnson et al., WO96/24702 A1, 1996). Also, Inoue, Japanese, registered Patent claiming compositions including 40˜70 atomic weight % of Cu (Inoue et al., WO02/053791 A1, 2002, Japanese Patent Application No. 2002-256401).
[0008] However, although bulk type amorphous materials (or bulk type nano composite materials) developed by present have strength and elastic limit higher than 2˜4 times in comparing with the existing metallic materials, it is difficult for them to be applied to structural materials because of their abrupt fracture behaviors. Such brittleness is caused by a formation of shear bands so that it must be resolved to put them to practical use.
[0009] Typically, in order to increase toughness of materials with brittleness such as ceramics, it has been using a method for dispersing ceramic particles or ductile metallic crystalloid. Such method, however, causes a fracture phenomenon such as a crack deflection, a branching, plural shear bands, blunting and so forth during cracking.
[0010] Accordingly, the method can be adapted to bulk type amorphous materials having the similar mechanical properties to those of ceramic materials.
SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide Cu-based bulk amorphous matrix composite materials containing high fusion point elements, which considerably increase the elongation rate while minimizing the reduction of strength of the bulk amorphous materials through adding high fusion point elements, Ta and/or W, so as to control abrupt fracture behaviors of the amorphous materials, and to a production method thereof.
[0012] In order to accomplish this object, there are provided Cu-based bulk amorphous matrix composite materials, comprising a Cu-based amorphous alloy containing high fusion point element(s) selected from a group of Ta, W or combination thereof, wherein the high fusion point element(s) has(have) a shape of crystalline grain and is(are) dispersed around a Cu-based amorphous matrix.
[0013] According to the present invention, the Cu-based amorphous matrix composite materials have the composition expressed as the following Chemical formula 1;
Cu a Zr b Ti c R d [Chemical Formula 1]
[0014] where R is Ta, W or combination thereof, a, b, c and d are atomic weight ratio, a+b+c+d equals 100, a, b, c, and d have the range of 45≦a≦65, 10≦b≦35, 5≦c≦30, and 5≦d≦10, respectively.
[0015] According to the present invention, the Cu-based amorphous matrix has above 90% of amorphous volume fraction.
[0016] According to another aspect of the present invention, there is provided a method for producing Cu-based amorphous matrix composite materials containing high fusion point element, the method comprising the steps of: (a) fusing high fusion point element(s), Ta or W, in a arc-melting furnace together with matrix element(s), Cu, Zr or Ti, thus producing a binary (matrix element-high fusion point element) master alloy; (b) arc-melting the binary alloy from the step (a) together with the matrix element(s), Cu, Zr or Ti, thus producing another master alloy with target composition; (c) melting the master alloy of the step (b) in the atmosphere of Ar in a Quartz tube using a radio-frequency melting furnace; and (d) injecting the fused metal of the step (c) into a molding die with blowing Ar gas, and solidifying the same.
[0017] According to the present invention, the composition of the master alloy in the step (c) satisfies the following Chemical formula 1;
Cu a Zr b Ti c R d [Chemical Formula 1]
[0018] where R is Ta, W or combination thereof, a, b, c and d are atomic weight ratio, a+b+c+d equals 100, a, b, c, and d have the range of 45≦a≦65, 10≦b≦35, 5≦c≦30, and 5≦d≦10, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0020] [0020]FIG. 1 is a photograph showing an end face of a specimen with 1 mm of diameter of Cu—Zr—Ti—Ta amorphous matrix composite materials produced by the present invention;
[0021] [0021]FIG. 2 is an X-ray diffractometer graph of Cu—Zr—Ti—Ta amorphous matrix composite materials produced by the present invention and of Cu—Zr—Ti amorphous materials of the prior art;
[0022] [0022]FIGS. 3 a to 3 c are microphotographs by transmission electron microscopic (TEM) for Cu—Zr—Ti—Ta amorphous matrix composite materials produced by the present invention;
[0023] [0023]FIG. 4 is a Differential Scanning Calorimetry (DSC) graph of Cu—Zr—Ti—Ta amorphous matrix composite materials produced by the present invention and of Cu—Zr—Ti amorphous materials of the prior art;
[0024] [0024]FIG. 5 is a stress-strain curve for Cu—Zr—Ti—Ta amorphous matrix composite materials produced by the present invention and for Cu—Zr—Ti amorphous materials of the prior art;
[0025] [0025]FIGS. 6 a to 6 c are photographs of Scanning Electron Microscopic (SEM) for fracture face and shear bands of a specimen of the prior Cu—Zr—Ti amorphous materials after fractured; and
[0026] [0026]FIGS. 7 a to 7 c are photographs of Scanning Electron Microscopic (SEM) for fracture face and shear bands of a specimen of Cu—Zr—Ti—Ta amorphous matrix composite materials of the present invention after fractured.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
[0028] Cu-based amorphous alloy used in the present invention can be produced in a shape of homogeneous bulk by an injection molding method or a suction molding method with relative fast cooling rate.
[0029] In the present invention, in order to complement strength of Cu-based amorphous materials, high fusion point element with high strength, W is added about 3˜7 atomic weight %, thus considerably improving strength and ductility as well comparing with existing Cu-based amorphous materials. Also, in order to complement ductility, high fusion point element with excellent ductility, Ta is added about 5˜10 atomic weight %, thus considerably improving ductility together with strength.
[0030] In the present invention, in order to produce Cu-based amorphous matrix composite materials containing high fusion point element(s), firstly, high purity matrix element(s), Cu, Zr or Ti are fused in an arc-melting furnace together with high fusion point element(s), Ta or W, thus to produce a binary (matrix element-high fusion point element) master alloy.
[0031] Referring to an equilibrium diagram, Ti—Ta, Ti—W, Ti—Zr, Zr—Ta, Ta—W and so forth form isomophous solid solution. That is to say, in the present invention, high fusion point element(s), Ta or W is(are) melted in the arc-melting furnace together with the matrix element(s), Cu, Zr or Ti according to a target combination of an alloy forming such isomophous solid solution, producing the binary (matrix element-high fusion point element) master alloy, which reduces fusion point of an alloy.
[0032] Then, the binary (matrix element-high fusion point element) master alloy is arc-melted together with the matrix element(s), Cu, Zr or Ti, producing Cu—Zr—Ti—R (R is Ta and/or W) master alloy. The master alloy produced is then melted and cooled to produce Cu-based amorphous matrix composite materials in which a certain fraction of Ta and/or W solid solution particles are dispersed around a Cu-based matrix with above 90% of amorphous volume fraction.
[0033] Hereinafter, the composition and effect of the present invention are described in detail with reference to various examples.
[0034] Although the following examples are described as follows, the present invention is not limited to the examples.
[0035] In order to compare mechanical properties of amorphous matrix composite materials of the present invention with Cu-based amorphous materials of the prior art, rod type specimens with 1 mm of diameter according to the present invention and the prior art, respectively were produced by an injection molding method.
EXAMPLE 1
[0036] In this example, Cu—Zr—Ti—Ta amorphous matrix composite material containing high fusion point element, Ta, was produced.
[0037] First, Zr and Ta elements with above 99.9 wt % of purity were fused in an arc-melting furnace, producing an binary master alloy having a composition of Zr 80 Ta 20 . Then, the master alloy was arc-melted together with Cu, Zr and Ti, producing an alloy having a composition of Cu 57 Zr 28.5 Ti 9.5 Ta 5 . Herein, the ratio of atomic weight of Cu:Zr:Ti is 60:30:10. The master alloy produced was fused in an atmosphere of Ar gas in the quartz tube using a radio-frequency melting furnace, Ar gas was injected into a Cu mold with excellent cooling ability, producing rod specimen with 1˜3 mm of diameter.
COMPARISON EXAMPLE 1
[0038] In order to compare mechanical properties of amorphous matrix composite materials produced from example 1, Cu-based amorphous alloy of Cu 60 Zr 30 Ti 10 in which ratio of atomic weight of Cu:Zr:Ti is 60:30:10 was produced.
[0039] In order to analyze the microstructure and solidification properties of the amorphous alloys produced by example 1 and comparison example 1, an optical microscope, SEM, X-ray diffractometer and TEM were used. Also, in order to analyze thermal characteristics of amorphous transitions, crystallization behaviors and so forth, Differential Scanning Calorimetry (DSC), Differential Thermal Analysis (DTA) and so forth were used. Herein, heating rate was set to 0.667 K/s and 0.333 K/s, respectively. Also, in order to analyze mechanical properties of amorphous phase and amorphous matrix composite materials produced, uniaxial compression test at rate of 10 −4 s −1 was conducted to a rod specimen with 1 mm of diameter and 2 mm of length, and a fracture face thereof was monitored by SEM.
[0040] Results from the various tests were provided in FIGS. 1 to 7 .
[0041] [0041]FIG. 1 is a photograph showing an end face of a specimen with 1 mm of diameter of Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite materials produced by example 1. As shown in FIG. 1, it can be known that crystal grains of below 10 μm were homogeneously dispersed around the matrix, producing composite material.
[0042] [0042]FIG. 2 is an X-ray diffractometer graph of Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite materials produced by example 1 and of Cu 60 Zr 30 Ti 10 amorphous materials of comparison example 1. Herein, x-axis is diffraction degree 2θ and y-axis is relative intensity.
[0043] As shown in FIG. 2, Cu 60 Zr 30 Ti 10 amorphous material of the prior art had diffraction pattern of typical amorphous materials with 2θ range of about 15°. Comparing with this, Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite materials of the present invention had diffraction pattern of amorphous material together with Ta solid solution peak of Body Center Cubic (BCC) structure.
[0044] [0044]FIGS. 3 a to 3 c are bright field image and selected area diffraction pattern of microphotographs by transmission electron microscopic (TEM) for Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite materials produced by example 1. Bright field image showed that the matrix and crystal grains existed. Particularly, selected area diffraction pattern showed that the matrix was amorphous and the crystal grains were BCC.
[0045] Accordingly, as shown in FIGS. 2 and 3, it was known that the Cu-based amorphous matrix composite material of the present invention was provided in which the matrix was amorphous and the crystal grains were Ta solid solution in BCC, FIG. 4 is a Differential Scanning Calorimetry (DSC) graph showing the results of thermal analysis of Cu 60 Zr 30 Ti 10 of amorphous materials of the prior art and of Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite materials produced by example 1. The results were shown in Table 1. In FIG. 4, x-axis indicates temperature K and y-axis indicates exothermic W/g.
TABLE 1 T x1 (K) T x2 (K) T x3 (K) Composition T g (K) ΔH 1 (J/g) ΔH 2 (J/g) ΔH 3 (J/g) Cu 60 Zr 30 Ti 10 729 751 805 901 −26.4 −24.8 −2.8 Cu 57 Zr 285 Ti 95 Ta 5 733 755 812 909 −22.5 −19.5 −3.1
[0046] As shown in FIG. 4 and Table 1, it can be known that thermal behaviors of Cu 60 Zr 30 Ti 10 amorphous material and Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite material were similar each other. Heating values at first crystallization behavior of Cu 60 Zr 30 Ti 10 amorphous material and Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite material were 26.5 J/g and 23.4 J/g, respectively, so that heating value of composite material was corresponding to about 88% of that of amorphous material. According to the result, it can be known that composite materials of the present invention were amorphous matrix composite materials containing about 10% of crystal grains.
[0047] [0047]FIG. 5 is a stress-strain curve for Cu 60 Zr 30 Ti 10 of amorphous material of the prior art and Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite material produced by example 1. Herein, x-axis indicates strain % and y-axis indicates stress MPa.
[0048] As shown in FIG. 5, Cu 60 Zr 30 Ti 10 amorphous material indicated that elongation rate was about 3.5% and strength was 2100 MPa, and Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite material indicated that elongation rate was about 14.5% and strength was 2300 MPa.
[0049] That is to say, amorphous matrix materials produced by the present invention improved in strength by about 200 MPa compared with prior amorphous materials, together with considerable improvement in ductility.
[0050] [0050]FIGS. 6 a to 6 c are photographs of Scanning Electron Microscopic (SEM) for fracture face and shear bands of the prior Cu 60 Zr 30 Ti 10 amorphous material after fractured. The fracture was proceeded in an angle of about 45 degrees relative to maximum shear stress direction. The fracture face was vein pattern typically generated in amorphous materials and had plural shear bands.
[0051] [0051]FIGS. 7 a to 7 c are photographs of Scanning Electron Microscopic (SEM) for fracture face and shear bands of Cu 57 Zr 28.5 Ti 9.5 Ta 5 amorphous matrix composite material produced by example 1 after fractured. As was in amorphous material, the fracture was proceeded in an angle of about 45° relative to maximum shear stress direction. The fracture face was vein pattern typically generated in amorphous materials.
[0052] Also, it can be known that while amorphous material of the prior art indicated about 3.5% of elongation rate due to fracture proceeded by plural shear bands, amorphous matrix composite material of the present invention indicated about 14.5% of improved elongation rate due to fracture proceeded by very many shear bands as shown in FIG. 7.
[0053] As shown in the embodiment, Cu-based amorphous matrix composite materials of the present invention have excellent strength and elongation rate comparing with common amorphous materials by adding high fusion point element(s) such as Ta and/or W, etc. Consequently, since Cu-based amorphous matrix composite materials of the present invention can prevent abrupt fracture behaviors generated in amorphous materials, they can be utilized in various industrial applications as structural materials requiring high strength and ductility.
[0054] As described above, Cu-based amorphous matrix composite materials of the present invention can minimize strength reduction of bulk type amorphous materials, considerably increase elongation rate that is known to be a drawback in amorphous materials, and provide excellent mechnical properties at room temperature, by adding high fusion point element such as Ta and/or W, etc.
[0055] Cu-based amorphous matrix composite materials of the present invention have excellent strength, wear resistance and corrosion resistance, so that they can be widely utilized in an area of machine parts having problems in wear and corrosion. For example, they can be widely adapted to a mid to high temperature light alloy used in rockets and air crafts for the military and to wear resistant alloy used in a transportation equipment for land, sea and air.
[0056] Also, Cu-based amorphous matrix composite materials containing high fusion point element of the present invention can be produced by economical mass production and effectively substitute for existing crystalline metallic materials, creating new industry, which provides wide applications and excellent ripple effect.
[0057] Although preferred embodiments of the present invention have 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. | In Cu-based bulk amorphous matrix composite materials, comprising a Cu-based amorphous alloy containing high fusion point element(s) selected from a group of Ta, W or combination thereof, wherein the high fusion point element(s) has(have) a shape of crystalline grain and is(are) dispersed around a Cu-based amorphous matrix. Cu-based bulk amorphous matrix composite materials have the composition expressed as the following Chemical formula 1;
Cu a Zr b Ti c R d [Chemical Formula 1]
where R is Ta, W or combination thereof, a, b, c and d are atomic weight ratio, a+b+c+d equals 100, a, b, c, and d have the range of 45≦a≦65, 10≦b≦35, 5≦c≦30, and 5≦d≦10, respectively. | 2 |
FIELD OF THE INVENTION
The invention relates to a propeller blade bearing arrangement that can be particularly advantageously implemented on longitudinally axially adjustable propeller blades of aircraft propellers.
BACKGROUND OF THE INVENTION
It is generally known to a person skilled in the art of propeller drives of aircraft that adjustable propeller blades of aircraft propellers serve to optimize the propeller efficiency in order to obtain an optimum propeller blade position for all propeller speeds. For this reason, it is necessary to individually fasten the propeller blades of the aircraft propeller to the propeller hub and, for facilitated adjustability, to mount said propeller blades in corresponding rolling bearings. A propeller blade bearing arrangement of said type is for example known from the British patent GB 2 244 525 A and is composed substantially of a propeller hub, to which a plurality of propeller blades are individually fastened in a corresponding number of blade receptacles of a blade carrier ring. Each propeller blade has, at its blade root, a primary adjustment bearing and a secondary adjustment bearing and is longitudinally axially mounted within a blade receptacle so as to be rotatable, with both the primary adjustment bearing and the secondary adjustment bearing being designed as angular rolling bearings which are arranged so as to be longitudinally axially spaced apart from one another and are braced against one another. Both adjustment bearings have one upper race and one lower race each and a row of rolling bodies which are arranged between said races, with the primary adjustment bearing being formed in a physical embodiment by an angular contact ball bearing, while the secondary adjustment bearing is designed as an angular roller bearing. In order to lubricate the entire adjustment mechanism for the propeller blades, a lubricating oil reservoir is arranged in the propeller hub, from which lubricating oil reservoir the primary and the secondary bearings are also supplied with lubricating oil by means of centrifugal force as the propeller rotates in order to avoid wear.
The assembly of the known propeller blade bearing arrangement takes place substantially in such a way that a bearing support sleeve, which surrounds the blade root of the propeller blade and forms in each case the seat of the upper races of the adjustment bearings, is initially assembled in two halves on the blade root, before the upper bearing rings, which are likewise composed of two halves, of the adjustment bearings are placed on said bearing support sleeve and can be connected in a suitable way to form continuous rings. A two-part cage is subsequently placed around the upper race of the secondary adjustment bearing and connected to form a ring, so that the rolling bodies of the secondary adjustment bearing can be inserted into the cage. A sleeve which partially has a thread at the outer side and, in the assembled state, forms, with a part of its inner side, the lower running track of the secondary adjustment bearing, is then pushed loosely, together with a cage for the rolling bodies of the primary adjustment bearing, over the blade root of the propeller blade, and the rolling bodies of the primary adjustment bearing are subsequently inserted into the cage. The loose sleeve on the blade root is thereafter pulled over the rolling bodies of the secondary adjustment bearing until said sleeve bears at the inside against said rolling bodies as a lower race, and subsequently, a two-part blade receptacle which, at the inside, contains the likewise two-part upper race of the primary adjustment bearing, is braced around the blade root in such a way that the upper race of the primary adjustment bearing rests on the rolling bodies of the latter. Finally, a threaded bracing ring which is supported against the assembled blade receptacle is screwed onto the thread of the sleeve, which is loose up until that time, on the blade root, so that on the one hand the outer race of the secondary adjustment bearing, which is formed by the inner side of the loose sleeve, is braced against the rolling bodies of the latter, and on the other hand, the two adjustment bearings of the propeller blade bearing arrangement are braced against one another. At the same time, the point at which the blade root emerges from the blade receptacle is sealed off in an oil-tight fashion by means of two seals which are arranged between the sleeve, which is designed at the inner side as a lower bearing ring of the secondary adjustment bearing, and the bearing support ring, and also between said sleeve and the blade receptacle.
A disadvantage of said known propeller blade bearing arrangement is, however, that the specific arrangement and design of the adjustment bearings for the propeller blade requires a largely two-part design of the entire propeller bearing arrangement, as a result of which a multiplicity of individual parts are required for each propeller bearing arrangement, which above all disadvantageously increases the risk of errors in their assembly. Since said individual parts must additionally be produced extremely precisely and with fitting accuracy with respect to one another, there is also a considerable time and cost expenditure for the assembly of the propeller blades to the propeller hub in addition to the high expenditure for production, so that a propeller blade bearing arrangement of said type entails very high overall production costs. Furthermore, from a safety-related point of view, a considerable disadvantage of said known propeller blade bearing arrangement is that the lubricating oil, which rises out of the lubricating oil reservoir in the propeller hub as a result of centrifugal force as the propeller rotates, can flow unhindered through the two adjustment bearings, and therefore at high propeller speeds, bears with a pressure which corresponds to the centrifugal acceleration against the two seals which are arranged at the point at which the blade root emerges from the blade receptacle. This can, in the case of a damaged seal at one of the propeller blade bearing arrangements of the aircraft propeller, lead to the loss of the entire quantity of lubricating oil in the propeller hub, which can result in failure of lubrication in the adjustment mechanism and the adjustment bearings of the propeller blade bearing arrangement as well as in function failures while the aircraft is in operation.
OBJECT OF THE INVENTION
Proceeding from the presented disadvantages of the known prior art, the invention is therefore based on the object of designing a propeller blade bearing arrangement, in particular for longitudinally axially adjustable propeller blades of aircraft propellers, with which the expenditure for the production of the individual parts of the bearing arrangement and the expenditure for the assembly of the propeller blade on the propeller hub can be reduced to a minimum and which is designed with a fail-safe function which, in the case of a damaged seal at the point at which the blade root emerges from the blade carrier ring, effectively prevents a loss of the entire quantity of lubricating oil in the propeller hub.
DESCRIPTION OF THE INVENTION
According to the invention, said object is achieved in a propeller blade bearing arrangement in that each propeller blade is designed as a fully preassembled modular unit with the two races and the rolling bodies of the primary adjustment bearing and of the secondary adjustment bearing, which modular unit can be screwed in the blade receptacle of the blade carrier ring in a lubricating-oil-tight fashion by means of an upper ring nut which is formed with a sealing with respect to the blade root of the propeller blade. The upper races of the primary and of the secondary adjustment bearing are connected to lubricating oil surge rings which enclose the lower races of said primary and of said secondary adjustment bearing axially at one side, by means of which lubricating oil surge rings the lubricating oil, which rises out of the lubricating oil reservoir in the propeller hub as a result of centrifugal force as the propeller blades rotate, can be stored largely within the adjustment bearings. At the same time, it is ensured by means of the lubricating oil surge rings on the adjustment bearings in conjunction with a defined filling quantity in the lubricating oil reservoir that the lubricating oil bears in only a small quantity and approximately unpressurized against the seal of the upper ring nut.
In one expedient refinement of the propeller blade bearing arrangement designed according to the invention, the pre-assembled modular unit composed of the propeller blade and the complete adjustment bearings is formed in that the primary adjustment bearing and the secondary adjustment bearing are braced against an annular shoulder on the blade root of the propeller blade by a lower ring nut via spacers which are arranged between said primary adjustment bearing and secondary adjustment bearing. Said annular shoulder is arranged at a conical transition region of the blade root to the propeller blade, and at the same time, axially forms the bearing seat for the upper race of the secondary adjustment bearing which is of greater diameter than the primary adjustment bearing. The bearing seat of the primary adjustment bearing is, in contrast, realized via the lower race of the latter and is arranged directly at the blade root of the propeller blade, with the lower end of the blade root of the propeller blade being formed with an external thread which is complementary to the internal thread of the lower ring nut.
Furthermore, as a further feature of the propeller blade bearing arrangement designed according to the invention, the spacers used between the adjustment bearings are on the one hand an inner spacer sleeve which is arranged between the lower race of the primary adjustment bearing and the upper race of the secondary adjustment bearing and that has a cross-sectional shape which is matched to the shape of the blade root and opens conically upward. On the other hand, an outer spacer ring is arranged as a further spacer between the upper race of the primary adjustment bearing and the lower race of the secondary adjustment bearing, which outer spacer ring is preferably designed, so as to reduce the number of individual parts of the propeller blade bearing arrangement and the risk of assembly errors, as a single-part integral component with the lower race of the secondary adjustment bearing. Regardless of whether the outer spacer ring is formed in one piece with the lower race of the secondary adjustment bearing or as a separate component, said outer spacer ring also has, at its outer side, additionally an annular web of increased diameter as a further integrated element, by means of which the blade root of the propeller blade can ultimately be screwed by the upper ring nut in the blade receptacle of the blade carrier ring of the propeller hub. In an advantageous embodiment of the propeller blade bearing arrangement designed according to the invention, it is additionally proposed that the lower race of the primary adjustment bearing preferably has a T-shaped cross-sectional profile, which is rotated by 180° with respect to the longitudinal central axis of the propeller hub, and is placed with the inner side of the transverse limb of said profile on the blade root of the propeller blade so as to form the bearing seat of the primary adjustment bearing. The underside of said transverse limb is at the same time designed as a pressure face for the lower ring nut, while the longitudinal limb and the outer part of the transverse limb of the profile of the lower race form the rolling body running face of the lower race of the primary adjustment bearing. The annular face, which is formed by the profile of the lower race of the primary adjustment bearing, between the blade root of the propeller blade and the longitudinal limb of said profile is advantageously additionally utilized as a contact face, at which the inner spacer sleeve, which bears against the lower race of the secondary bearing, is supported on the primary bearing between the primary adjustment bearing and the secondary adjustment bearing.
A further feature of the propeller blade bearing arrangement designed according to the invention is that the lubricating oil surge rings which are connected to the upper races of the primary and of the secondary adjustment bearing are preferably designed as angle rings which are formed in one piece with the upper race, which angle rings, with the horizontal limb of their profile, form an extension of the upper side of the upper races, and with the vertical limb of their profile, are aligned toward the propeller hub. It has proven to be particularly advantageous to design the vertical limb of the lubricating oil surge rings of the two adjustment bearings with a length which corresponds approximately to the height of the upper race of the respective adjustment bearing in order that the upper races of the two adjustment bearings form a relatively large annular space together with the lubricating oil surge rings. In this annular space which encloses the lower race of the adjustment bearings and which is open only toward the propeller hub, a relatively large quantity of the, during rotation of the propeller, centrifugally accelerated lubricating oil from the lubricating oil reservoir of the propeller hub, can collect and always ensure sufficient lubrication of the adjustment bearings. The single-part design of the lubricating oil surge rings with the upper races of the adjustment bearings serves again to reduce the number of individual parts of the propeller bearing arrangement, though it should not be precluded that said lubricating oil surge rings can also be designed as separate components and be suitably connected to the upper races of the adjustment bearings.
It is finally also proposed as a final feature of the propeller blade bearing arrangement designed according to the invention that the vertical limb of the lubricating oil surge ring of the primary adjustment bearing is arranged between the longitudinal limb of the profile of the lower race of the primary adjustment bearing and the inner spacer sleeve in such a way that a remaining gap between the inner side of the lubricating oil surge ring and the outer side of the longitudinal limb of the lower race, and between the outer side of the spacer sleeve and the inner side of the lubricating oil surge ring, forms a lubricating oil overflow labyrinth to the secondary adjustment bearing. That limb of the lubricating oil surge ring of the secondary adjustment bearing which is likewise aligned toward the propeller hub is, in the same way, arranged between the lower race of the secondary adjustment bearing and the upper ring nut, so that here, too, a remaining gap between the inner side of the lubricating oil surge ring and the outer side of the lower race, and between the outer side of the lubricating oil surge ring and the inner side of the ring nut, forms a lubricating oil overflow labyrinth to the seal of the upper ring nut.
Said lubricating oil overflow labyrinths on both adjustment bearings serve to reduce the pressure of the lubricating oil which is accelerated centrifugally out of the propeller hub as the propeller rotates, as a result of which the lubricating oil bears approximately unpressurized against the seal, which seals off the point at which the blade root emerges from the blade receptacle of the blade carrier ring, on the upper ring nut. This takes place in such a way that the lubricating oil which rises out of the propeller hub initially fills only the annular space, formed by the lubricating oil surge ring, in the primary bearing. The quantity of lubricating oil which can no longer be stored in the primary adjustment bearing is then pressed by centrifugal force through the overflow labyrinth on the primary adjustment bearing into the cavity formed between the inner spacer sleeve and the outer spacer ring, from where said lubricating oil passes under centrifugal force into the secondary adjustment bearing, and is stored there in turn in the annular space formed by the lubricating oil surge ring of said secondary adjustment bearing. With corresponding dimensioning of the lubricating oil filling quantity, only a small quantity of excess lubricating oil can then flow via the lubricating oil overflow labyrinth on the secondary adjustment bearing to the seal on the upper ring nut, with said small quantity of lubricating oil no longer exerting any damaging pressure loadings on the seal. Should damage to the seal on the upper ring nut nevertheless occur, then only said small quantity of lubricating oil can be lost, since most of the lubricating oil is stored by the lubricating oil surge rings in the adjustment bearings of the propeller blade bearing arrangement.
The propeller blade bearing arrangement designed according to the invention therefore has the advantage over the propeller blade bearing arrangements known from the prior art that, by means of the design of the propeller blade as a fully pre-assembled modular unit with the primary bearing and the secondary bearing, the expenditure for the production of the individual parts of the propeller blade bearing arrangement and the expenditure for the assembly of the propeller blades on the propeller hub is reduced to a minimum. It is possible during the pre-assembly of the modular unit to use angular rolling bearings, which are merely slightly modified at their races and are known per se, both for the primary adjustment bearing and for the secondary adjustment bearing, which angular rolling bearings can be produced cost-effectively and are fastened to the blade root with a precisely-set preload with respect to one another. The propeller blade which is pre-assembled in this way can then be inserted into a single-part blade receptacle of the blade carrier ring on the propeller hub, and is screwed to the propeller hub merely by means of an upper ring nut, so that, as a result of the small number of individual parts for the propeller blade bearing arrangement, the assembly expenditure and the risk of assembly errors is considerably reduced, and the production costs of the propeller blade bearing arrangement are reduced overall. Furthermore, as a result of the design of the primary adjustment bearing and of the secondary adjustment bearing with lubricating oil surge rings which axially enclose their lower races, the propeller blade bearing arrangement designed according to the invention has sufficient lubrication, at all times, of the adjustment mechanism and of the adjustment bearings, and also a fail-safe function, as a result of which, in the case of a damaged seal at the point at which the blade root emerges from the blade carrier ring, only a small quantity of lubricating oil can be lost, but a loss of the entire quantity of lubricating oil in the propeller hub is effectively prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
One preferred embodiment of the propeller blade bearing arrangement designed according to the invention is explained in more detail below with reference to the appended drawing. Here, the single FIGURE shows a sectioned view through a bearing arrangement, designed according to the invention, of a propeller blade.
DETAILED DESCRIPTION OF THE DRAWINGS
The drawing clearly shows a propeller blade bearing arrangement for a longitudinally axially adjustable propeller blade of an aircraft propeller, which propeller blade bearing arrangement is composed substantially of a propeller hub 1 (not illustrated in any more detail), to which a plurality of propeller blades 2 (only indicated in the drawing) are individually fastened in a corresponding number of blade receptacles 3 of a blade carrier ring. Each propeller blade 2 has, at its blade root 4 , a primary adjustment bearing 5 and a secondary adjustment bearing 6 and is longitudinally axially mounted within a blade receptacle 3 so as to be rotatable, with both the primary adjustment bearing 5 and the secondary adjustment bearing 6 being designed as angular rolling bearings which are arranged so as to be longitudinally axially spaced apart from one another and are braced against one another. The primary adjustment bearing 5 , like the secondary adjustment bearing 6 , has one upper race 7 , 9 and one lower race 8 , 10 and also rolling bodies 11 , 12 which are arranged between said races 7 , 9 , 8 , 10 , with both adjustment bearings 5 , 6 being designed as angular contact ball bearings with different bearing bores. In order to lubricate the entire adjustment mechanism for the propeller blades 2 , a lubricating oil reservoir 13 (likewise only indicated in the drawing) is arranged in the propeller hub 1 , from which lubricating oil reservoir 13 the primary and the secondary bearings 5 , 6 are supplied with lubricating oil by means of centrifugal force as the propeller rotates.
The drawing also clearly shows that each propeller blade 2 is designed according to the invention as a fully pre-assembled modular unit in each case with the two races 7 , 9 , 8 , 10 and the rolling bodies 11 , 12 of the primary adjustment bearing 5 and of the secondary adjustment bearing 6 , which modular unit can be screwed in the blade receptacle 3 of the blade carrier ring in a lubrication-oil-tight fashion by means of an upper ring nut 15 which is formed with a seal 14 with respect to the blade root 4 of the propeller blade 2 . Clearly visible, the upper races 7 and 9 of the primary and of the secondary adjustment bearing 5 and 6 are connected to lubricating oil surge rings 16 , 17 which in each case enclose the lower races 8 and 10 of said primary and of said secondary adjustment bearing 5 and 6 axially at one side, by means of which lubricating oil surge rings 16 , 17 the lubricating oil, which rises out of the lubricating oil reservoir 13 in the propeller hub 1 as a result of centrifugal force as the propeller blades 2 rotate, is stored largely within the adjustment bearings 5 , 6 , and by means of which lubricating oil surge rings 16 , 17 , in conjunction with a defined filling quantity in the lubricating oil reservoir 13 , the lubricating oil bears in only a small quantity and approximately unpressurized against the seal 14 of the upper ring nut 15 .
Here, the pre-assembled modular unit composed of the propeller blade 2 and the complete adjustment bearings 5 , 6 is formed in that the primary adjustment bearing 5 and the secondary adjustment bearing 6 are braced against an annular shoulder 19 on the blade root 4 of the propeller blade 2 by a lower ring nut 18 via spacers which are arranged between said primary adjustment bearing 5 and secondary adjustment bearing 6 . As the drawing also shows, the spacers between the adjustment bearings 5 , 6 are designed on the one hand as an inner spacer sleeve 20 which is arranged between the lower race 8 of the primary adjustment bearing 5 and the upper race 9 of the secondary adjustment bearing 6 , and on the other hand as an outer spacer ring 21 which is arranged between the upper race 7 of the primary adjustment bearing 5 and the lower race 10 of the secondary adjustment bearing 6 , with the outer spacer ring 21 being designed as a single-part integral component with the lower race 10 of the secondary adjustment bearing 6 . In addition, said outer spacer ring 21 also has an annular web 22 of increased diameter, by means of which the blade root 4 of the propeller blade 2 is screwed by the upper ring nut 15 in the blade carrier ring 3 of the propeller hub 1 .
It is also clear from the drawing, that the lower race 8 of the primary adjustment bearing 5 has a T-shaped cross-sectional profile, which is rotated by 180° with respect to the longitudinal central axis of the propeller hub 1 , and is placed with the inner side of the transverse limb 23 of said profile on the blade root 4 of the propeller blade 2 . The underside 24 of said transverse limb 23 is at the same time designed as a pressure face for the lower ring nut 18 , while the longitudinal limb 25 and a part of the transverse limb 23 of the profile of the lower race 8 of the primary adjustment bearing 5 form the rolling body running face, which is embodied as a ball groove, of the lower race 8 . The annular face 26 , which is formed by the profile of the lower race 8 of the primary adjustment bearing 5 , between the blade root 4 of the propeller blade 2 and the longitudinal limb 25 of said profile is additionally utilized as a contact face, at which the inner spacer sleeve 20 , which bears against the lower race 8 of the secondary bearing 6 , is supported on the primary bearing 5 between the primary adjustment bearing 5 and the secondary adjustment bearing 6 .
The lubricating oil surge rings 16 , 17 which are connected to the upper races 7 , 9 of the primary and of the secondary adjustment bearing 5 , 6 are also, as is clearly illustrated in the drawing, formed by angle rings which are formed in one piece with the upper races 7 , 9 , which angle rings, with the horizontal limb 27 , 29 of their profile, form an extension of the upper side of the upper races 7 , 9 , and with the vertical limb 28 , 30 of their profile, are aligned toward the propeller hub 1 . Here, the vertical limb 28 of the lubricating oil surge ring 16 of the primary adjustment bearing 5 is arranged between the longitudinal limb 25 of the profile of the lower race 8 of the primary adjustment bearing 5 and the inner spacer sleeve 20 in such a way that a remaining gap between the inner side of the lubricating oil surge ring 16 and the outer side of the longitudinal limb 25 of the lower race 8 and between the outer side of the spacer sleeve 20 and the inner side of the lubricating oil surge ring 16 forms a lubricating oil overflow labyrinth 31 to the secondary adjustment bearing. In the same way, the vertical limb 30 of the lubricating oil surge ring 17 of the secondary adjustment bearing 6 is also arranged between the lower race 10 of the secondary adjustment bearing 6 and the upper ring nut 15 , so that at this point, too, a remaining gap between the inner side of the lubricating oil surge ring 17 and the outer side of the lower race 10 and between the outer side of the lubricating oil surge ring 17 and the inner side of the ring nut 15 forms a lubricating oil overflow labyrinth 32 to the seal 14 of the upper ring nut 15 .
LIST OF REFERENCE SYMBOLS
1 Propeller hub
2 Propeller blade
3 Blade receptacle
4 Blade root
5 Primary adjustment bearing
6 Secondary adjustment bearing
7 Upper race of 5
8 Lower race of 5
9 Upper race of 6
10 Lower race of 6
11 Rolling bodies of 5
12 Rolling bodies of 6
13 Lubricating oil reservoir
14 Seal
15 Upper ring nut
16 Lubricating oil surge ring on 5
17 Lubricating oil surge ring on 6
18 Lower ring nut
19 Annular shoulder
20 Inner spacer sleeve
21 Outer spacer ring
22 Annular web
23 Transverse limb
24 Underside
25 Longitudinal limb
26 Annular face
27 Horizontal limb of 16
28 Vertical limb of 17
29 Horizontal limb of 17
30 Vertical limb of 17
31 Lubricating oil overflow labyrinth
32 Lubricating oil overflow labyrinth | The invention relates to a propeller blade bearing, for the propeller blades of aircraft propellers that can be adjusted along their longitudinal axis, a plurality of propeller blades being individually fastened on a propeller hub in a corresponding number of blade seats. Every propeller blade, at its blade base, has a primary adjustable bearing and a secondary adjustable bearing and is received so as to be rotatable along its longitudinal axis inside a blade seat. The primary and the secondary adjustable bearing are configured as angular contact ball bearings that have respective upper bearing races and lower bearing races and rolling bodies interposed between said bearing races. A lubricating oil reservoir is arranged in the propeller hub and supplies the primary and the secondary adjustable bearing with lubricating oil when the propeller rotates. Every propeller blade is configured as a completely pre-assembled unit with the primary adjusting bearing and the secondary adjusting bearing. The upper bearing races of the primary and the secondary adjustable bearing are connected to respective lubricating oil overflow rings which axially enclose the lower bearing races on one side and which allow to store the lubricating oil from the lubricating oil reservoir in the propeller hub mainly in the adjustable bearings. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to pharmaceutical compositions and methods for the treatment of irritable bowel disease (IBD) [also termed: irritable bowel syndrome (IBS)]; more particularly for the treatment of diarrhea-predominant IBD.
2. Description of the Prior Art
Irritable bowel syndrome (IBS), a chronic or recurring gastrointestinal disorder, afflicts as many as 24% of women and 19% of men in the U.S., Europe, Japan, and China. IBS produces abdominal pain or discomfort in its victims and accounts for about one-eighth of primary care and more than one-fourth of gastroenterology practice. IBS has tremendous societal and economic impact since persons with IBS symptoms miss three times as many work days as those without and incur 70% higher health care costs. The American Gastroenterological Association has recently underscored the importance of IBS by issuing both a position statement (American Gastroenterological Association (AGA) Medical Position Statement: Irritable Bowel Syndrome. Gastroenterology 112:2118-2119 (1997)) and a technical review (Drossman D A, Whitehead W E, Camilleri M., “Irritable bowel syndrome: a technical review for practice guideline development”, Gastroenterology 112:2120-2137 (1997)) on IBS. The description herein of IBS is based chiefly on these documents and on other current literature (such as that reviewed in Snape W J Jr., “Irritable bowel syndrome”, In: Bockus Gastroenterology, 5th edition (W. S. Haubrich, F. Schoffner, ed.) Philadelphia: W. B. Saunders, pp. 1619-1636 (1995)).
IBS presents itself as abdominal pain accompanied by altered bowel habits. There is no established biological marker for IBS, which appears to result from faulty regulation in both the gastrointestinal and nervous systems. Once clinicians rule out other possible causes of IBS symptoms, they must devise a treatment plan based upon the severity and nature of the symptoms as well as other factors such as the degree of impairment the individual is experiencing in the activities of daily living. At present, treatment options range from education and dietary modification to drug therapy to psychological therapy. Drug and/or psychological therapy is called for in those 30% of IBS patients with moderate or severe symptoms. Given an IBS prevalence of 19% to 24%, IBS sufferers requiring such therapy represent 6-7% of the population at large, or well over 100 million individuals in continual need of such therapy in the U.S., Europe, Japan, and China.
While the symptoms of IBS have a physiological basis, no physiological mechanism unique to IBS has been identified. Rather, the same mechanisms that cause occasional abdominal discomfort in healthy individuals operate to produce the symptoms of IBS. The symptoms of IBS are therefore a product of quantitative differences in the motor reactivity of the intestinal tract, and increased sensitivity to stimuli or spontaneous contractions.
Due to a lack of readily identifiable structural or biochemical abnormalities in this syndrome, the medical community has developed a consensus definition and criteria, known as the Rome criteria, to aid in diagnosis of IBS. According. to the Rome criteria, IBS is indicated by abdominal pain or discomfort which is (1) relieved by defecation and/or (2) associated with a change in frequency or consistency of stools, plus two or more of the following: altered stool frequency, altered stool form, altered stool passage, passage of mucus, and bloating or feeling of abdominal distention (Dalton, C. and Drossman, D. A., Am Fam Physician 1997 55(3):875-880). Thus, a hallmark of IBS is abdominal pain that is relieved by defecation, and which is associated with a change in the consistency or frequency of stools. IBS may be diarrhea-predominant, constipation-predominant, or an alternating combination of both.
Persons with IBS exhibit hypersensitivity, particularly hyperalgesia, in response to painful distensions in the small bowel and colon and to normal intestinal function. Furthermore, there are also increased or unusual areas of visceral pain. The abdominal pain is often poorly localized, and may be migratory and/or variable in nature. The pain may be worsened by meals and reduced upon defecation. Furthermore, IBS symptoms, including hyperalgesia, are commonly initiated or exacerbated by stress (Dalton, C. and Drossman, D. A., Am Fam Physician 1997 55(3):875-880).
Women apparently are more often affected than men, and the prevalence of irritable bowel syndrome is lower among the elderly (Camilleri, M. and Choi, M.-G., Aliment Pharmacol Ther 1997 11(1):3-15). It also seems clear that psychological factors, either stress or overt psychological disease, modulate and exacerbate the physiological mechanisms that operate in IBS (Drossman, D. A. et al., Gastroenterology 1988 95:701-708; Gaynes B N, Drossman D A: The role of psychosocial factors in irritable bowel syndrome. Baillieres Best Prac Res Clin Gastroenterol 13:437-452, 1999; Jones J, Boorman J, Cann P, Forbes A, Gomborone J, Heaton K, Hungin P, Kumar D, Libby G, Spiller R, Read N, Silk D, Whorwell P: British society of gastroenterology guidelines for the management of the irritable bowel syndrome. Gut 47:ii 1-ii 19, 2000). Some studies suggest that only about 10% to 50% of those afflicted with IBS actually seek medical attention. Nonetheless, IBS still accounts for up to about 3.5 million physician visits per year, and is the most common diagnosis in gastroenterologists' practice, accounting for about 25% of all patients (Camilleri and Choi, 1997). In a study published in 1993, persons afflicted with IBS were found to have more frequent doctor visits, a lower quality of life, and to miss three times as many days from work as those with no bowel symptoms (Drossman, D. A., Dig Dis Sci 1993 38:1569-1580). As a consequence, persons with IBS incur higher health care costs than those without IBS (Talley, N. J. et al., Gastroenterology 1995 109:1736-1741).
The AGA position statement recommends antispasmodic (anticholinergic) medication for IBS pain and bloating, or a tricyclic antidepressant or serotonin-selective reuptake inhibitor if the pain is severe. Dietary fiber is recommended (cisapride is also mentioned) for IBS constipation, whereas loperamide is recommended for diarrhea. For treatment of IBS patients presented with predominant diarrhea, the bile acid sequestrant “cholestyramine may be considered for a subgroup of patients with cholecystectomy or who may have idiopathic bile acid malabsorption.” Clearly, there is no single pharmacologic treatment appropriate to all IBS sufferers. However, it is equally clear that it is acceptable clinical practice to employ a bile acid sequestrant to treat diarrhea associated with IBS.
The technical review issued by the AGA states that treatment with the bile acid sequestrant “cholestyramine should be considered in patients with IBS who have predominant diarrhea.” Cholestyramine, a copolymer of styrene and divinylbenzene possessing trimethylbenzylammonium groups, has a somewhat limited capacity to bind bile acids, so very large quantities (as much as 20 grams per day) must be ingested in order to alleviate symptoms.
There is presently no effective treatment for irritable bowel syndrome (K. B. Klein, Controlled treatment trials in the irritable bowel syndrome: a critique, Gastroenterology 95: 232-241, 1988). Although largely ineffective, current treatment is multifactorial and consists of stress management, diet, and drugs, in that order. The patient is reassured that the disease is not life threatening and is advised to reduce or eliminate any controllable stress in his or her life. Relaxation exercises and biofeedback may be attempted to alter the psychogenic components of the illness. With respect to diet, the patient is advised to avoid any food to which he or she possesses a known sensitivity with respect to exacerbating the problem. A high fiber diet, either insoluble wheat bran or soluble psyllium, is almost routinely recommended, but with little if any positive benefit (Dietary fiber, food intolerance, and irritable bowel syndrome, Nutrition Reviews 48: 343-346, 1990).
Numerous drugs have been tried for the treatment of irritable bowel syndrome, but none has demonstrated sufficient efficacy to be of practical benefit to most patients. Psychoactive drugs, such as anxiolytics and antidepressants, even if effective for a given patient, have very limited, short-term utility because of the high potential for addiction to and abuse of these agents. Antispasmodics and various antidiarrheal preparations have been used but, even if they are effective, long-term treatment is precluded by problems such as development of tolerance, toxicity, or abuse potential. Several excellent reviews examine in detail the symptomology, diagnosis, and treatment of irritable bowel syndrome. These include: W. L. Hasler and C. Owyang, Irritable bowel syndrome, In: Textbook of Gastroenterology, Ed. by T. Yamada, J. B. Lippincott Company, Philadelphia, Pa., 1696-1714 (1991); M. M. Schuster, Irritable bowel syndrome, In: Gastrointestinal Disease, Pathophysiology Diagnosis and Management, Fourth Edition, Ed. by M. H. Sleisenger, J. S. Fordtran, W. B. Saunders Company, Philadelphia, Pa., 1402-1418 (1989); W. S. Haubrich, Irritable bowel syndrome, Gastroenterology, Fourth Edition, Ed. by J. E. Berk,. W. B. Saunders Company, Philadelphia, Pa., 2425-2444 (1985) and Jones J, Boorman J, Cann P, Forbes A, Gomborone J, Heaton K, Hungin P, Kumar D, Libby G, Spiller R, Read N, Silk D, Whorwell P: British society of gastroenterology guidelines for the management of the irritable bowel syndrome. Gut 47:ii 1-ii 19, (2000).
Numerous patents have claimed activities of various types represented as being effective for relieving irritable bowel syndrome symptoms. For the most part they relate to substances which possess spasmolytic activity and thereby decrease intestinal motility. U.S. Pat. Nos. 4,611,011, 4,701,457, and 4,745,131 disclose a series of amidinoureas which reduce intestinal motility and are useful for treating irritable bowel syndrome. 1-Azabicyclo[2.2.2]octan-3-yl-2-aryl-3-azacyclo-2-hydroxypropionates and their quaternary salts, which possess antispasmodic activity and are useful for treating irritable bowel syndrome, are disclosed in U.S. Pat. No. 4,843,074. Calcium channel antagonists exhibit muscle relaxing and antispasmodic activities. A series of substituted imidazolyl-alkyl-piperazine and diazepine derivatives, disclosed in U.S. Pat. No. 5,043,447, are calcium channel antagonists and may be useful as antispasmodics for treating irritable bowel syndrome. 2-Aminomethylalkynylalkyl-1,3-dithiane derivatives with calcium-channel blocking activity and potentially similar uses are disclosed in U.S. Pat. No. 4,877,779. A series of triazinone derivatives with spasmolytic activity for treating irritable bowel syndrome are disclosed in U.S. Pat. No. 4,562,188.
In addition to antispasmodic agents, compounds with other activities have been disclosed which may relieve the symptoms of irritable bowel syndrome. U.S. Pat. No. 4,239,768 discloses a series of arylimidazolidinylidene ureas which decrease the sensitivity of the bowel to distension and thereby relieve irritable bowel symptoms. U.S. Pat. No. 4,970,207 discloses a series of benzodiazepine derivatives which are cholecystokinin antagonists and which may be useful for a large number of medical indications which include irritable bowel syndrome.
Since diarrhea is one frequent component of irritable bowel symptomatology, anti-diarrheal agents have been used to treat this disease. Unfortunately, such agents tend to exacerbate the constipatory phase of the disease and are, therefore, of little practical, long-term benefit.
Attempts to treat IBS generally focus on either (1) treatments directed to the intestinal tract (so-called “end organ therapy”) or (2) treatments directed to affective disorders mediated by the CNS which are associated with IBS (Farthing, M. J. G., Drugs 1998 56(1):11-21). Among the former are gut transit accelerants, such as wheat bran, soluble fiber, and polycarbophil calcium, for constipation-predominant IBS; antidiarrheals, such as loperamide, diphenoxylate, and codeine phosphate, for diarrhea-predominant IBS; and anticholinergics and smooth muscle relaxants, such as cimetropium bromide, pinaverium bromide, octilium bromide, trimebutine, and mebeverine, for diarrhea-predominant IBS and abdominal pain. In addition, alterations in diet have been targeted for those patients with food sensitivities or food allergies.
The end organ therapy treatments for IBS have proved ineffective or contain inherent drawbacks that limit their usefulness. For example, while the gut accelerants are useful to accelerate gut transit, they also exacerbate abdominal pain and bloating. Likewise, while antidiarrheals, such as loperamide, are often effective in treating diarrhea-predominant IBS, they are ineffective in treating the additional symptoms associated with IBS, such as abdominal pain. As a consequence, end organ therapy often is limited to patients with mild or moderate symptoms.
The anticholinergics and smooth muscle relaxants are effective in relieving pain associated with IBS, although their effects on other symptoms associated with IBS is unclear (Committee, Gastroenterology 1997 112:2120-2137; Pace, F. et al., Digestion 1995 56:433-442). In addition, some of the most effective compounds in these classes are not available for use in the United States, since they have not been approved by the Federal Food and Drug Administration (Committee, 1997). Finally, dietary alterations are of limited utility for a small segment of IBS patients.
Central nervous system treatments have received attention as potential IBS therapies because of the well recognized link between affective disorders and IBS, and also because of the disturbances in bowel health that occurs in individuals with these disorders. The tricyclic antidepressants, such as amitriptyline, imipramine, and doxepin, are frequently used to treat IBS, due to the neuromodulatory and analgesic properties of these compounds, which are independent of their psychotropic effects. However, because of their psychotropic properties, administration of these drugs requires long-term care, and are usually only given to patients with severe or refractory symptoms, impaired daily function, and associated depression or anxiety attacks. Furthermore, the newer antidepressants, in particular the specific serotonin reuptake inhibitors, such as fluoxetine, serraline, and paroxetine, have not been shown to be more effective than the tricyclic antidepressants, although some anecdotal evidence suggests these compounds may have fewer side effects (Committee, 1997).
Nalmefene glucuronide, an opioid receptor antagonist, has been investigated as a treatment for constipation-predominant IBS (Chami, T. N., et al., Am J Gastroenterol 1993 88:1568 [abstract]). Over an eight-week period, eight patients received 16 mg nalmefene glucuronide three times a week. While the patients reported decreased transit time and increased stool frequency, nalmefene glucuronide did not reduce abdominal pain or bloating, and stool consistency was not improved. The present inventors believe that the failure of nalmefene to treat pain associated with IBS can be attributed to the fact that this study used a high dose of nalmefene which antagonizes both excitatory and inhibitory opioid receptor-mediated functions in the gut as well as in the CNS. This view is supported by recent evidence that 1,000-fold lower doses of nalmefene (ca. 15 μg, IV) have been shown to markedly enhance morphine's analgesic potency (Joshi et al., Anesthesiol. 1999, 90(4): 1007-11), whereas doses of >0.5 mg markedly attenuate opioid analgesia (Konieczko, K. M. et al., Br J Anaesth 1988 61(3):318-23).
Recent reports of successful treatment of IBS patients with high doses of the kappa opioid agonist, fedotizine (30 mg, three times daily) (Dapoigny, M. et al., Dig Dis Sci 1995 40(10):2244-9; Gue, M. et al., Gastroenterology 1994 107(5):1327-34) may be due to masking of supersensitized excitatory opioid receptor activity in the gut by activation of inhibitory opioid receptor functions, analogous to methadone maintenance of opioid addicts. Supersensitized excitatory opioid receptor functions in the gut may also result in tolerance to the analgesic effects of endogenous opioids (Wang, L. and Gintzler, A. R., J Neurochem 1995 64(3):1102-6), which could account for the abnormal visceral pain associated with IBS.
U.S. Pat. No. 5,512,578 discloses that the analgesic potency of bimodally-acting opioid agonists can be enhanced, and the tolerance/dependence liability reduced, upon coadministration of ultralow doses of selective excitatory opioid receptor antagonists. As used herein, “excitatory opioid receptor antagonists” are compounds that bind to and inactivate excitatory opioid receptors, but not inhibitory opioid receptors, on neurons in the nociceptive pathways. Such selective excitatory opioid receptor antagonists include, when administered at appropriately low doses, naloxone, naltrexone, etorphine, and dihydroetorphine. The selective excitatory opioid receptor antagonists attenuate excitatory, but not inhibitory, opioid receptor functions in nociceptive (pain) pathways of the peripheral and central nervous systems. As a result, symptoms associated with activation of excitatory opioid receptors, such as anti-analgesia, hyperalgesia, hyperexcitability, physical dependence and/or tolerance effects, are blocked, whereas the analgesic effects of bimodally acting opioid agonists, which are mediated by the inhibitory opioid receptors, are unmasked and thereby enhanced (see Crain, S. M. and Shen, K.-F., Proc Natl Acad Sci USA 1995 92:10540-10544; Crain, S. M. and Shen, K.-F., Trends Pharmacol Sci 1998 19:358-365; Ann NY Acad Sci 1998 845:106-25; Shen, K.-F. and Crain, S. M., Brain Res 1997 757(2):176-90). The predictions based on these preclinical studies have been recently confirmed by clinical studies on postsurgical patients which demonstrated that cotreatment with morphine plus low-dose naloxone or nalmefene markedly enhanced the analgesic potency of morphine administered over 24-hour test periods (Joshi et al., Anesthesiol. 1999, 90(4): 1007-11; Gan, T. J. et al., Anesthesiol. 1997 87:1075-1081).
U.S. Pat. No. 5,512,578 further discloses that ultralow doses of naltrexone can, alone or in combination with low-dose methadone, provide effective longterm maintenance treatment for opioid addiction to prevent relapse to drug abuse. Furthermore, ultralow doses of selective excitatory opioid receptor antagonists can be administered alone to chronic pain patients to enhance the analgesic potency and reduce the tolerance/dependence liability of endogenous opioid peptides, such as enkephalins, dynorphins, and endorphins, which are elevated in chronic pain patients (Crain and Shen, 1995). However, there is no teaching or suggestion in U.S. Pat. No. 5,512,578 that administration of a selective excitatory opioid receptor antagonist would be useful in treating symptoms of IBS. In particular, there is no teaching or suggestion that administration of a selective excitatory opioid receptor antagonist would be useful in treating symptoms of IBS that are unrelated to the nociceptive pathways, such as stool frequency or consistency.
U.S. Pat. No. 5,472,943 also discloses a method wherein coadministration of an ultralow dose of a selective excitatory opioid receptor antagonist with a bimodally-acting opioid agonist selectively enhances the analgesic effect of the bimodally-acting opioid agonist while reducing the undesirable side-effects associated with longterm administration of the opioid agonist. However, U.S. Pat. No. 5,472,943 does not disclose that a selective excitatory opioid receptor antagonist can be used in the absence of a bimodally-acting opioid agonist.
Both U.S. Pat. Nos. 5,580,876 and 5,767,125 also disclose a method to selectively enhance the analgesic effect of a bimodally-acting opioid agonist while reducing unwanted side-effects associated with the administration of the opioid agonist by coadministration of the opioid agonist with an amount of an excitatory opioid receptor antagonist, such as naltrexone or nalmefene, effective to enhance the analgesic effect of the bimodally-acting opioid agonist while reducing the undesirable side-effects. U.S. Pat. Nos. 5,580,876 and 5,767,125 disclose use of an excitatory opioid receptor antagonist alone for treatment of opioid addicts, and do not teach or suggest that administration of a selective excitatory opioid receptor antagonist would be useful in treating symptoms of IBS. In particular, there is no teaching or suggestion that administration of a selective excitatory opioid receptor antagonist would be useful in treating other symptoms of IBS, such as stool frequency or consistency.
U.S. Pat. No. 5,585,348 relates to a method for reducing hyperalgesia associated with administration of nerve growth factor or related growth factors. The method comprises administration of a selective excitatory opioid receptor antagonist prior to or simultaneously with the administration of nerve growth factor. However, U.S. Pat. No. 5,585,348 does not disclose that the selective opioid receptor antagonist may be administered in the absence of nerve growth factor, and does not teach or suggest that the administration of a selective excitatory opioid receptor antagonist alone would be useful in treating IBS.
In spite of the many treatments and inventions devised to relieve or prevent irritable bowel syndrome, the unfortunate fact is that presently no suitable long term, safe and efficacious treatment or preventative is available for this troublesome and widespread disease.
It is an object of the invention to provide novel pharmaceutical compositions and methods for the long term, safe and efficacious treatment of irritable bowel disease (IBD) or syndrome (IBS).
SUMMARY OF THE INVENTION
The above and other objects are realized by the present invention, one embodiment of which relates to a method for treating irritable bowel syndrome in a subject in need of such treatment, comprising administering to the subject an amount of a polyamine effective to treat irritable bowel syndrome in the subject, the polyamine being selected from the group consisting of:
R—NH—(CH 2 ) a —NH—(CH 2 ) b H—(CH 2 ) c —NH 2 , 1)
CF 3 —C 6 H 5 —(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —NH—(CH 2 ) d —NH—(CH 2 ) e —C 6 H 5 —CF 3 , 2)
R—NH—(CH 2 ) a —NH—C 6 H 6 —NH—(CH 2 ) b —NH—R 3)
and
PIP—(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —PIP, 4)
wherein:
R is alkyl, aryl, aralkyl, alkaryl, or cyclo-alkyl having up to about 10 carbon atoms, and any of the alkyl chains may optionally be interrupted by at least one etheric oxygen atom,
PIP is piperidine and
a, b, c, d, and e may be the same or different and are integers from 1-10.
Another embodiment of the invention concerns a pharmaceutical composition adapted for administration to a subject suffering from irritable bowel syndrome comprising a therapeutically effective amount of a polyamine as described above to treat irritable bowel syndrome and a pharmaceutically acceptable carrier therefor.
A still further embodiment of the invention comprises an article of manufacture comprising packaging material and a pharmaceutical agent contained within the packaging material, wherein the pharmaceutical agent is effective for the treatment of a subject suffering from irritable bowel syndrome, and wherein the packaging material comprises a label which indicates that the pharmaceutical agent can be used for ameliorating the symptoms associated with irritable bowel syndrome, and wherein the pharmaceutical agent is selected from the group consisting of polyamines having the formula:
R—NH—(CH 2 ) a —NH—(CH 2 ) b H—(CH 2 ) c —NH 2 , 1)
CF 3 —C 6 H 5 —(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —NH—(CH 2 ) d —NH—(CH 2 ) e —C 6 H 5 —CF 3 , 2)
R—NH—(CH 2 ) a —NH—C 6 H 6 —NH—(CH 2 ) b —NH—R 3)
and
PIP—(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —PIP, 4)
wherein:
R is alkyl, aryl, aralkyl, alkaryl, or cyclo-alkyl having up to about 10 carbon atoms, and any of said alkyl chains may optionally be interrupted by at least one etheric oxygen atom,
PIP is piperidine and
a, b, c, d, and e may be the same or different and are integers from 1-10.
DETAILED DESCRIPTION OF THE INVENTION
The invention arose out of research directed toward the evaluation of a group of polyamine analogues as agents to ameliorate diarrhea-predominant irritable bowel syndrome. Each compound was assessed when administered subcutaneously (SC) in a psychological stress-induced model of irritable bowel syndrome in rodents for its ability to reduce stool output in a dose-dependent manner. The spermine pharmacophore was found to be an excellent platform from which to construct compounds to treat irritable bowel syndrome. The activity of the compounds is critically dependent on both the nature of the terminal substituent groups and the geometry of the groups separating the nitrogens of the polyamines. In addition to the SC studies, several compounds, N 1 ,N 11 -diethylnorspermine, N 1 ,N 12 diethylspermine, N 1 ,N 12 diisopropylspermine, N 1 ,N 14 -diethylhomospermine, N,N′-bis[5-(ethylamino)pentyl]-1,4-butanediamine, N,N′-bis[2-(4-piperidinyl)ethyl]-1,4-diaminobutane, and N,N′-bis[3-(ethylamino)propyl]-trans-1,4-cyclohexanediamine, were subsequently evaluated for oral efficacy. The remarkable activity of N,N′-bis[3 (ethylamino)propyl]-trans-1,4-cyclohexanediamine led to further exploration of this framework as a pharmacophore for the construction of other analogues to relieve the symptoms of diarrhea-predominant IBS.
As noted above, Irritable Bowel Syndrome (IBS) is a chronic disorder that occurs in 15-20 percent of the US population and accounts for up to 50% of outpatient referrals to gastroenterologists (Slepoy V D, Stella M, Pezzotto S M, Kraier L, Burde L, Wohlwend K, Razzari E, Polento L: Irritable bowel syndrome clinical and psychopathological correlations. Dig Dis Sci 44:1008-1012, 1999). It is characterized by altered bowel function, i.e., constipation, diarrhea, or alternating constipation and diarrhea, with or without abdominal pain (Schmnulson M W, Chang L: Diagnostic approach to the patient with irritable bowel syndrome. Am J Med 107:20S-26S, 1999). Although the pathogenesis remains controversial, this malady is considered primarily a psychosocial or psychiatric disorder by some (Gaynes B N, Drossman D A: The role of psychosocial factors in irritable bowel syndrome. Baillieres Best Prac Res Clin Gastroenterol 13:437-452, 1999; Jones J, Boorman J, Cann P, Forbes A, Gomborone J, Heaton K, Hungin P, Kumar D, Libby G, Spiller R, Read N, Silk D, Whorwell P: British Society of Gastroenterology guidelines for the management of the irritable bowel syndrome. Gut 47:ii 1-ii 19, 2000), others have suggested immunological and inflammatory mechanisms (Collins S M, Vallance B, Barbara G, Borgaonkar M: Putative inflammatory and immunological mechanisms in functional bowel disorders. Baillieres Best Prac Res Clin Gastroenterol 13:429-436, 1999) or abnormalities of intestinal motility and/or enhanced visceral sensitivity (Gaynes, supra; Farthing M J: Irritable bowel syndrome: New pharmaceutical approaches to treatment. Baillieres Best Prac Res Clin Gastroenterol 13:461-471, 1999). Thus, it is possible that IBS may be managed by chemotherapeutic means, including using agents that modify intestinal motility (Gaynes, supra).
Tansy and co-workers, in a series of well-conceived studies, first demonstrated the striking impact of polyamines on the motility of the gastrointestinal (GI) tract (Tansy M F, Martin J S, Landin W E, Kendall F M, Melamed S: Sperrnine and spermidine as inhibitors of gastrointestinal motor activity. Surg Gyn Obst 154:74-80, 1982). The original work focused on poly(ethyleneimine) and gastric emptying. Branched-chain poly(ethyleneimine)s effected significant inhibition of gastric emptying in rodents (Melamed S, Carlson G R, Moss J N, Belair E J, Tansy M R GI pharmacology of polyethyleneimine I: Effects on gastric emptying in rats. J Pharm Sci 66:899-901, 1977); however, their therapeutic potential was compromised by the observation that the same compounds elicited a severe retch response in dogs (Tansy M F, Martin J S, Innes D L, Kendall F M, Melamed S, Moss J N: GI pharmacology of polyethyleneimine II: Motor activity in anesthetized dogs. J Pharm Sci 66:902-904, 1977). Nevertheless, because of the structural relationship between the poly(ethyleneimine)s and natural polyamines, the study moved forward; the effects of spermidine, spermine, and a group of polyamine analogues on the gastric emptying of rodents were also investigated (Belair E J, Carlson G. R, Melamed S, Moss J N, Tansy M R Effects of spermine and spermidine on gastric emptying in rats. J Pharm Sci 70:347, 1981). It soon became apparent that polyamines had a considerable influence on gastric emptying and that “endogenous spermine and spermidine may have some unrecognized GI secretornotor activity” (Belair et al, supra). It also became obvious, from a structure-activity perspective, that minor alterations in the polyamine's structure could completely abolish the molecule's ability to inhibit gastric emptying. Thus, these studies strongly suggested that the polyamine pharmacophore was an excellent candidate for the construction of antitransit, antidiarrheal drugs.
For example, although N 1 ,N 11 -diethylnorspermine [DENSPM; DE(3,3,3)], was ineffective in a rodent castor oil-induced diarrhea model (Bergeron R J, Yao G W, Yao H, Weimar W R, Sninsky C A, Raisler B, Feng Y, Wu Q, Gao F: Metabolically programmed polyamine analogue antidiarrheals. J Med Chem 39:2461-2471, 1996), the polyamine analogue predicated on a different backbone only three methylene units longer, N 1 ,N 14 -diethylhomospermine [DEHSPM; DE(4,4,4)], is a very potent antidiarrheal as demonstrated in a number of animal models and in the clinic against AIDS-related diarrhea (Sato T L, Sninsky C A, Bergeron R J, Structural specificity of synthetic analogues of polyamines and their effect on gastrointestinal motility. In Polyamines and the gastrointestinal tract, Falk Symposium, no 62. R H Dowling, U R Folsch, C Loser (eds). Boston, Kluwer Academic, 1991; Sninsky C A, Bergeron R: Potent anti-diarrheal activity of a new class of compounds: Synthetic analogs of the polyamine pathway. Gastroenterology 104:A54, 1993). Unfortunately, the N-de-ethylated metabolite of DEHSPM, homospermine (HSPM), has a very protracted half-life, 2-3 weeks in mice and even longer in the dog (Bergeron R J, Weimar W R, Luchetta G, Sninsky C A, Wiegand J: Metabolism and pharmacokinetics of N 1 ,N 14 -diethylhomospermine. Drug Metab Dispos 24:334-343, 1996). Each subsequent dose of DEHSPM results in a further accumulation of HSPM until toxic levels of the metabolite are reached. Furthermore, SC administration of DEHSPM to three dogs at a daily dose of 2 mg/kg for 11-17 days resulted in ventricular bigeminies. The arrhythmia was apparent in a 6-lead EKG as early as three days into the dosing period (Bergeron R J, Wiegand J, Weimar W R, Snyder P S, Porter C W, Braylan R C: Chemical resection of the exocrine pancreas. Pancreas:, 2001-Submitted).
It was then attempted to circumvent the accumulation of HSPM by assembling a dihydroxylated DEHSPM derivative, (3R, 12R)-N 1 ,N 14 -diethyl-3,12-dihydroxyhomospermine [(R,R)—(HO) 2 DEHSPM]. The presence of the hydroxyl groups would, theoretically, yield a more metabolically labile compound. Indeed, this was found—(HO) 2 DEHSPM was as effective an antidiarrheal as DEHSPM, yet its residence time in most mouse tissues was shorter than that of DEHSPM. In addition, the induction of cardiac bigeminies observed in (HO) 2 DEHSPM-treated dogs was minimal. Unfortunately, when dogs were given (HO) 2 DEHSPM at a dose of 4.3 mg/kg/day for 14 days or 2.15 mg/kg/d for 28 days, exocrine pancreatic insufficiency developed approximately 40 days post-final dose and became severe within an additional 14 days; histological analysis revealed that the acinar-derived exocrine pancreas was severely atrophied. Although the hydroxylated DEHSPM derivative considerably decreased stool output in a castor oil-induced diarrhea model in rats with little build-up of either drug or metabolite in most tissues of mice and dogs, its long-term toxicity profile is unacceptable; the problem of designing a metabolically labile polyamine analogue still remains.
Thus, DENSPM, DEHSPM and (HO) 2 DEHSPM possess drawbacks as antidiarrheal agents. The former was more metabolically labile by virtue of its aminopropyl components, but was ineffective in reducing stooling; the latter two, although effective, were metabolically inert after de-ethylation to HSPM (DEHSPM) or caused exocrine pancreatic insufficiency [(HO) 2 DEHSPM]. In the retrograde processing of both spermidine (SPD) and spermine (SPM), the aminopropyl ends of these systems are first acetylated by spermidine/spermine-N 1 -acetyltransferase (SSAT); the nearest internal carbon-nitrogen bond is oxidized to an imine; and the imine is hydrolyzed to 3-acetamidopropanal and the corresponding amine. Spermine is thereby converted to SPD and a mole of 3-acetamidopropanal, and SPD yields putrescine and 3-acetamidopropanal. Since DENSPM contains aminopropyl moieties, it is processed by this mechanism to yield 3-acetamidopropanal, N-ethyinorspermine, N-ethyinorspermidine, N-ethyl-1,3-diaminopropane, norspermidine, and diaminopropane (Bergeron R J, Weimar W R, Luchetta G, Streiff R R, Wiegand J, Perrin J, Schreier K M, Porter C, Yao G W, Dimova H: Metabolism and pharmacokinetics of N 1 ,N 11 -diethyinorspermine. Drug Metab Dispos 23:1117-1125, 1995).
Therefore, if dialkylated SPMs ameliorated diarrhea and were subsequently dealkylated, the issue of metabolite (i.e., SPM) build-up would not be problematic as with HSPM. The catabolic processing should be similar to what was observed with DENSPM. However, in this instance, three natural products-SPM, SPD, and putrescine-are generated. Thus, we investigated a series of SPM [(3,4,3)] analogues in a castor oil-induced diarrhea model (Bergeron R J, Wiegand J, McManis J S, Weimar W R, Smith R E, Algee S E, Fannin T L, Slusher M A, Snyder P S: Polyamine analogue antidiarrheals: A structure-activity study. J Med Chem 44:232-244, 2001). We found that the SPM backbone was an excellent framework from which to construct active antidiarrheals with acceptable toxicity profiles. The current work describes an assessment of a series of polyamine analogues for their ability to reduce psychological stress-induced fecal output in a rodent model of IBS and strongly suggests that the polyamine pharmacophore is a useful platform from which to construct therapeutics suitable for treatment of diarrhea-predominant IBS.
All of the polyamines and chemical compounds described herein are known in the prior art. The polyamines are described as well as methods for their preparation are described in U.S. Pat. Nos. 6,297,287; 6,274,630; 6,262,125; 6,235,794; 6,184,232; 6,147,262; 6,034,139; 5,962,533; 5,866,613; 5,827,894; 5,677,352; 5,510,390; 5,462,970; 5,455,277; 5,393,757; 5,342,945; and Bergeron R J, McManis J S, Liu C Z, Feng Y, Weimar W R, Luchetta G R, Wu Q, Ortiz-Ocasio J, Vinson J R T, Kramer D, Porter C: Antiproliferative properties of polyamine analogues: A structure-activity study, J Med Chem 37:3464-3476, 1994; Bergeron R J, Feng Y, Weimar W R, McManis J S, Dimova H, Porter C, Raisler B, Phanstiel O: A comparison of structure-activity relationships between spermidine and spermine analogue antineoplastics. J Med Chem 40:14751494, 1997; Bergeron R J, McManis J S, Weimar W R, Schreier K M, Gao F, Wu Q, Ortiz-Ocasio J, Luchetta G R, Porter C, Vinson J R T: The role of charge in polyamine analogue recognition. J Med Chem 38:2278-2285, 1995; and Bergeron et al, J. Med Chem. 44:232-244 (2001), the entire contents and disclosures of all and each of which are incorporated herein by reference.
For the acute toxicity assessment the CHX(3,4,3)-trans was administered to female CD-1 mice (Charles River, Wilmington, Mass.) as a single intraperitoneal (IP) injection. The animals were carefully observed post-dosing and were scored 2 h after administration of the drug.
For drug preparation and administration, the compounds were put into solution with sterile normal saline and sonicated briefly, if necessary. The drugs were made up at concentrations such that the rats received the drugs PO or SC at the rate of 1 cc per kilogram. Mice received the CHX(3,4,3)-trans IP at 1 cc per 100 grams. The solutions were made fresh the day of the study. Control animals received an equivalent amount of saline PO or SC.
IBS-like symptoms, e.g., increased myoelectric activity and colonic contractility, have been induced in healthy human volunteers by subjecting them to various forms of physical or psychological stress[Almy TP, Tulin M: Alterations in colonic function in man under stress: Experimental production of changes simulating the “irritable colon”. Gastroenterology 8:616-626, 1947; Drossman D A, Powell D W, Sessions J T: The irritable bowel syndrome. Gastroenterology 73:811-822, 1977; Narducci F, Snape W J, Battle W M, London R L, Cohen S: Increased colonic motility during exposure to a stressful situation. Dig Dis Sci 30:40-44, 1985; Tache Y, Monnikes H, Bonaz B, Rivier J: Role of CRF in stress-related alterations and colonic motor function. Ann NY Acad Sci 697:233-243, 1993]. Animal models of stress-associated motility disorders, e.g., irritable bowel syndrome, have included such stressors as partial or complete body restraint at room temperature (Kishibayashi N, Miwa Y, Hayashi H, Ishi A, Ichikawa S, Nonaka H, Yokoyama T, Suzuki F: 5-HT3 receptor antagonists. 3. Quinoline derivatives which may be effective in the therapy of irritable bowel syndrome. J Med Chem 36:3286-3292, 1993; Lenz H J, Raedler A S, Greten H, Vale W W, Rivier J E: Stress-induced gastrointestinal secretory and motor responses in rats are mediated by endogenous corticotropin-releasing factor. Gastroenterology 95:1510-1517, 1988; Williams C L, Villar R G, Peterson J M, Burks T F: Stress-induced changes in intestinal transit in the rat: A model for irritable bowel syndrome. Gastroenterology 94:611-621, 1988) or cold (Barone F C, Deegan J F, Price W J, Fowler P J, Fondacaro I D, Ormsbee H S I: A model of stress-induced increased fecal output and colonic transit. Gastroenterology 90:AI337, 1986; Barone F C, Deegan J F, Price W J, Fowler P J, Fondacaro J D, Ormsbee H S I: Stress-induced diarrhea is not associated with abnormal gut secretion. Gastroenterology 90:AI337, 1986; Barone F C, Deegan J F, Price W J, Fowler P J, Fondacaro J D, Ormsbee HSI: Cold-restraint stress increases rat fecal pellet output and colonic transit. Am J Physiol 258:G329-G337, 1990), a conditioned fear response caused by placing the rats into cages in which they had previously experienced inescapable footshocks (Gue M, Junien J L, Bueno L: Conditioned emotional response in rats enhances colonic motility through the release of corticotropin-releasing factor. Gastroenterology 100:964-970, 1991), or by exposing the animals to psychological stress involving passive avoidance of an aversive stimulus, water (Bonaz B, Tache Y: Water-avoidance stress-induced c-fos expression in the rat brain and stimulation of fecal output: Role of corticotropin-releasing factor. Brain Res 641:21-28, 1994; Enck P, Merlin V, Erckenbrecht J F, Weinbeck M: Stress effects on gastrointestinal transit in the rat. Gut 30:455-459, 1989; Mormikes H, Schmidt B G, Tache Y: Psychological stress-induced colonic transit in rats involves hypothalamic corticotropin-releasing factor. Gastroenterology 104:716-723, 1993; Sninsky C A, Broome T A, Brooderson R J, Bergeron R J: Diethylhomospermine, a synthetic polyamine analog, prevents psychological stress-induced acceleration of colonic transit in rats. Gastroenterology 106:A569, 1994).
Subjecting the rats to any of the above stressors results in an increase in colonic transit and fecal output similar to what was observed in the healthy human volunteers that were subjected to physical or psychological stress. Of these animal models, we chose the latter, psychological stress, to be used for the screening of a series of our synthetic polyamine analogues for their ability to minimize the stress-associated increase in fecal output.
Animal care and experimental procedures were approved by the Institutional Animal Care and Use Committee. Male Sprague-Dawley rats (250-350 g, Harlan Sprague-Dawley, Indianapolis, Ind.) were housed in polycarbonate cages in a temperature- and humidity-controlled room with a 12-hour light/dark cycle. The experiments were performed at the same time of the day to decrease diurnal variability. A typical experiment involved 20 rats: 5 saline-treated controls and 5 pretreated with polyamine analogues at each of three doses as either a SC injection or a PO gavage. The rats in the SC studies and in one set of experiments involving PO administration were allowed ad libitum access to a standard rodent diet and tap water until the morning of the experiment. Stress was initiated 30 minutes post drug as described below. In another set of experiments involving PO administration, the animals were fasted overnight but were allowed free access to water. The animals were then stressed from ½ h to 2 h post-drug (data not shown). In a final experiment, non-stressed control rats were injected with saline SC and housed in individual polycarbonate cages. The fecal output (number of pellets) of the stressed and unstressed animals was recorded at 30-min intervals for a 6-h period, during which they received no food or water.
Once the drug had been administered, the animals were housed individually in polycarbonate cages containing a clear 70×50 mm Pyrex crystallization dish (Fisher, Pittsburgh, Pa.) inverted in the center and held in place with vacuum grease. To initiate the stress, water was added to each cage to a depth of at least 4.5 cm, i.e., within 0.5 cm of the top of the Pyrex dish. To avoid contact with water, the rats stand on the glass dish for the 6 h of the study. Stool output was expressed as the total number of fecal pellets excreted over the 6-h collection period. Percent reduction was calculated by dividing the mean value from the treated animals (T) by the mean value from the control animals (C), subtracting the resulting quotient from 1.0, and multiplying by 100 [i.e., (1.0−T/C)×100].
A one-tailed t-test assuming unequal variance was performed on the stool output data of the treated vs control (0 mg/kg) animals for each compound. A value of P<0.05 was considered significant.
This structure-activity study was designed to identify the best platform from which to construct therapeutic agents for controlling diarrhea in IBS patients and was predicated on earlier work with many of these analogues as antidiarrheals. The first polyamine analogue that was found to be effective against both diarrhea and IBS was DEHSPM. Unfortunately, this compound displayed an unacceptable toxicity profile. Thus, our intent was to identify those structural components of the analogues responsible for the anti-lBS properties and partition them from the toxic fragments. Accordingly, DEHSPM was modified in three ways (Table I): (a) changing the distance between the nitrogens and the overall length of the molecule [e.g., compounds 1, 3, and 14 versus DEHSPM], (b) altering the terminal alkyl groups within a series of compounds possessing the same backbone [e.g., DESPM (3) and compounds 4-11], and (c) keeping the overall length of the molecule the same but manipulating the ordering of the distance between the nitrogens (e.g., 16 versus 13).
The psychological stress-induced IBS model involves subjecting the rats to an aversive stimulus (water) and observing the increase in fecal output over a period of time. The compounds were generally administered SC at doses of 2.3, 11.6, 23.2, and 57.8 μmol/kg, equivalent to 1, 5, 10, or 25 mg/kg of DEHSPM. Control rats received an equivalent amount of saline SC. The unstressed control rats (n=15) excreted 3.1±3.1 fecal pellets over the 6-h collection period. The stool output (number of pellets) for the stressed control and treated animals are in Table 1.
Compounds predicated on a (3,3,3) backbone (DENSPM, DIPNSPM) were ineffective at diminishing stress-induced fecal output (Table 1). Extending the backbone of the norspermine compounds by one methylene group in the center to yield the (3,4,3) SPM systems substantially enhanced the anti-IBS activity of the compounds. Furthermore, small alterations in the terminal alkyl groups of SPM analogues could also have a profound effect on the drug's anti-lBS properties (Table 1). Because the (3,4,3) analogues demonstrated generally good activity, the comparison among them is best made at intermediate doses. In the IBS model at the 23.2 μmol/kg dose, DESPM (3) significantly reduced stress-elicited stooling by 35% (P<0.001). At the same dose, the bis-n-propyl spermine analogue DPSPM (4) diminished stooling by 74% (P<0.001), returning the stool output of the stressed rats to within error of the unstressed controls (P>0.1). At one-half the dose (11.6 μmol/kg) the bis-n-butyl compound DBSPM (5) completely eliminated fecal output (P<0.001). Branching the n-propyl groups of 4 to DIPSPM (6) yielded a compound that, at the 11.6 μmol/kg dose, substantially reduced stooling even more, from a 48% reduction observed with 4 to a 90% reduction with 6 (P<0.001). Even at one-half this dose, 5.8 μmol/kg, stool output was reduced by 70% relative to the stressed controls (P<0.001) and was within error of the stool output of the unstressed animals (P>0.1). However, at the 11.6 μmol/kg dose, the same branching change in 5 to DIBSPM (7) actually diminished activity at this dose, from a 100% decrease in fecal output with 5 to a 34% reduction with 7.
Removal of one of the isobutyl groups of 7 to generate MIBSPM (8) had little, if any, effect on activity. Adding a methylene to each of the terminal substituents of 7 to generate the corresponding pentyl analogue DIPESPM (9) had a minimal effect on activity at lower doses. Finally, the introduction of aromatic benzyl groups as in DBZSPM (10) or as in DTFMPhESPM (11) only served to diminish the activity relative to DESPM and DPSPM, respectively. However, the most remarkable of all of the (3,4,3) systems was CHX(3,4,3)-trans (12); a 100% reduction in fecal output was observed at a dose of 0.58 μmol/kg (P<0.001), and a dose of 0.145 μmol/kg reduced stool output by 80% (P<0.001), to a level within error of the unstressed controls (P>0.1). In addition, a 50% diminution in fecal output was observed at a dose of 0.07 μmol/kg (P<005). When allometrically scaled, the dose of 0.07 μmol/kg in the rat translates into a dose of only 0.3 mg for a 60-kg patient.
On expanding the methylene backbones from (3,3,3) systems (e.g., DENSPM) to (3,4,3) (e.g., DESPM) to (4,4,4) moieties (DEHSPM), there was an improvement in their anti-IBS activity (Table 1). However, further expansion of the backbone to a (5,4,5) base [DE(5,4,5), 14; PIP(5,4,5), 15] did not result in any enhancement of activity. Finally, to assess the importance of overall length of the molecules relative to how the methylene backbones are disposed, two unsymmetrical analogues [DE(3,3,6), 16; DIP(3,3,6), 17] were synthesized and evaluated. Interestingly, DE(3,3,6) has the same overall length as DEHSPM, but the former was less active. In keeping with the results from DIPSPM versus DESPM, DIP(3,3,6) was more active than was its diethyl counterpart (Table 1).
Because an orally active compound would be desirable for the treatment of IBS, selected analogues utilizing oral administration in the same model were assessed. In the initial studies animals were utilized that had been fasted overnight. Rodents were then given the drug of interest PO by gavage and stressed ½ h, 1 h, or 2 h post-drug. Unfortunately, because of the low baseline stool output in fasted control rats, the reductions in fecal output observed upon drug administration cannot be reported with any confidence (data not shown). Thereafter, only non-fasted animals were employed and were given the agents by gavage at doses of 11.6, 23.2, 57.8, or 115.6 μmol/kg 30 minutes before initiating the stress. Of all of the compounds evaluated [DENSPM, DESPM, DIPSPM, CHX(3,4,3)-trans, DEHSPM, DE(5,4,5), and PIP(5,4,5)], only CHX(3,4,3)-trans, DEHSPM, and DE(5,4,5) showed any activity at all (Table 2). At doses of 11.6 and 23.2 μmol/kg, CHX(3,4,3)-trans reduced stooling by about 80% (P=0.001 and <0.001, respectively). DEHSPM was effective at a dose of 115.6 μmol/kg (40% diminution of fecal output; P<0.01), and DE(5,4,5) was active at doses of 23.2 and 57.8 μmol/kg (55 and 73% reductions in fecal output, respectively; P<0.001 for both doses).
The acute toxicity of CHX(3,4,3)-trans IP in female CD-1 mice is about 150 mg/kg, and there is a strong neurological component to the toxic effects not apparent in DESPM- or DEHSPM-treated mice, which usually display a generalized depression with respiratory failure. At toxic doses (≧125 mg/kg, single dose), the CHX(3,4,3)-trans-treated mice, in addition to depression and respiratory failure, also displayed uncoordinated movements, intention tremors, and severe motor dysfunction, especially of the hind limbs. It is critical to point out that this dose, allometrically scaled, is at least 1000 times the dose of 0.0625 mg/kg needed to reduce fecal output of the stressed animals to that of the unstressed controls. However, signs of motor dysfunction, including seizures, have been observed in a rodent antidiarrheal model in rats treated with this drug at doses ≧1 mg/kg (Bergeron, R J et al., Polyamine Analogue Antidiarrheals: A Structure—Activity Study. A Med. Chem., Vol. 44, pages 232-244 (2001). The 1 mg/kg dose is, nevertheless, greater than 30 times the lowest dose (0.03125 mg/kg) that reduced stool output by >50% relative to the stressed controls. Thus, there is a large therapeutic window between a clinically effective dose in rats and a neurotoxic dose.
Signs of neurotoxicity similar to those described above in mice were observed in rats treated with DBSPM, DIBSPM, and DIPESPM at subtherapeutic doses equivalent to a 5 mg/kg dose of DEHSPM (Bergeron, supra). In the current study, the rats treated with DBSPM at doses of 11.6 or 57.8 μmol/kg, or DIPESPM at a dose of 57.8 μmol/kg were removed from the experiment after only 2 h (DBSPM) or 4.5 h (DIPESPM) due to severe neurotoxicity. In addition, all of the rats in the DBSPM 57.8 μmol/kg group died within ˜24 h post-dosing. Therefore, it seems that the longer, more lipophilic N-alkyl substituents result in increased neurotoxicity upon administration to animals.
Whereas the current guidelines for treating IBS primarily involve either managing psychological and psychosocial factors or altering a patient's diet, some pharmacological interventions have been marginally successful in treating IBS. These include antidepressants, codeine, the antimotility agent loperamide, and the bile salt-binding resin cholestyramine. Since some cases of IBS may be the result of abnormalities of intestinal motility and/or enhanced visceral sensitivity, it follows that those agents which alter intestinal motility would be beneficial to this subset of patients. Accordingly, we have exploited our previous experience in the development of polyamine analogue antidiarrheal agents to find analogues suitable for the treatment of diarrhea-predominant IBS.
The design concept was predicated on partitioning those structural components of the analogues responsible for the anti-lBS properties from those which are toxic. The alterations of the polyamine analogues fell into three categories: (a) changing the distance between the nitrogens and the overall length of the molecule, (b) keeping the overall length of the molecule the same but manipulating the ordering of the distance between the nitrogens, and (c) altering the terminal groups within a series of compounds possessing the same backbone. Expansion of the methylene backbones from (3,3,3) systems (e.g., DENSPM) that were completely ineffective upon SC administration to stressed rats, to (3,4,3) (e.g., DESPM), to (4,4,4) moieties (DEHSPM) resulted in improved anti-IBS activity; however, further expansion of the backbone to a (5,4,5) base did not result in any corresponding improvement of efficacy. The ordering and arrangement of the nitrogens within the methylene backbone seem to be critical to the compound's effectiveness; rearrangement of a (4,4,4) system to a (3,3,6) backbone of equal length actually reduced the activity in the rodent IIBS model.
The effects of manipulating the terminal alkyl groups on a particular backbone on the molecule's efficacy can be examined for several systems: (3,3,3) (DENSPM vs. DIPSPM), (3,3,6) [DE(3,3,6) vs. DIP(3,3,6)], and (3,4,3), which was the most thoroughly studied backbone in the present work. Changing the terminal diethyl groups of, e.g., DESPM, to isopropyl, e.g., DIPSPM, resulted in markedly improved efficacy. In fact, with the exception of the isobutyl- versus n-butyl spermines, the branched-chain analogues appeared to have increased activity when compared with their n-alkyl counterparts. This is in keeping with the observation that the branched-chain polyethyleneimines were highly active in inhibiting gastric emptying in rats, but the linear polyethyleneimine was not. However, the longer, more lipophilic N-alkyl substituents resulted in increased neurotoxicity when administered SC to the rats. In addition, the use of larger branched groups, e.g., isopentyl, did not enhance the activity of the spermine backbone; furthermore, the introduction of aromatic benzyl groups seemed to diminish the efficacy. However, in the end, the (3,4,3) analogue containing a cyclohexane ring in its center, CHX(3,4,3)-trans, is the most effective against stress-induced stooling, regardless of the mode of administration. This polyamine was also the most effective of the SPM analogues tested in the castor oil-induced diarrhea model. Although signs of motor dysfunction including seizures have been observed in a rodent antidiarrheal model in rats treated with this drug at doses ≧12 mg/kg, the 1 mg/kg dose is, nevertheless, greater than 30 times the lowest dose (0.03125 mg/kg) that reduced stool output by >50% relative to the stressed controls providing an acceptable therapeutic window.
TABLE 1
ACTIVITY OF POLYAMINE ANALOGUES AGAINST STRESS-INDUCED IRRITABLE BOWEL SYNDROME a
Dose, kg −1
Cmpd. No.
Structure/Abbreviation
mg
μmol
n
Stool Output b
P-Value c
% Reduction d
Norspermines (3,3,3)
1
0 0.90 4.51 22.6
0 2.3 11.6 57.8
5 5 5 5
12.4 ± 5.2 17.4 ± 5.1 15.2 ± 4.5 13.4 ± 5.9
— >0.05 >0.05 >0.05
— NS NS NS
2
0 0.97 4.8 24.2
0 2.3 11.6 57.8
5 5 5 5
14.2 ± 7.6 17.6 ± 5.5 13.6 ± 3.2 7.4 ± 3.6
— >0.05 >0.05 >0.05
— NS NS NS
Linear Spermine Analogues (3,4,3)
3
0 9.3 14 24
0 23.2 35.4 61
29 15 15 5
19.1 ± 6.4 12.5 ± 2.9 9.0 ± 6.3 2.8 ± 2.7
— <0.001 <0.001 <0.001
— 35 53 90
4
0 1 5 10 25
0 2.3 11.6 23.2 57.8
10 5 10 10 5
22.2 ± 11.3 11.4 ± 7.2 11.5 ± 8.7 5.7 ± 4.1 0.2 ± 0.4
— <0.05 <0.05 <0.001 <0.001
# — 49 48 74 99
5
0 1.1 5.3 e 26.6 e,f
0 2.3 11.6 57.8
5 5 5 5
22.8 ± 3.8 14.0 ± 4.8 0 ± 0 0 ± 0
— <0.01 <0.001 <0.001
— 39 100 100
6
0 2.5 5
0 5.8 11.6
5 5 5
15.6 ± 3.6 4.6 ± 2.3 1.6 ± 1.8
— <0.001 <0.001
— 70 90
7
0 1.1 5.3 10.7 g
0 2.3 11.6 23.2
10 10 10 10
18.4 ± 3.3 15.9 ± 5.7 12.2 ± 2.7 6.6 ± 3.1
— >0.05 <0.001 <0.001
— NS 34 64
8
0 0.94 4.7 9.4 g
0 2.3 11.6 23.2
5 5 5 5
21.2 ± 4.4 14.8 ± 3.8 11.2 ± 2.2 10.6 ± 2.9
— <0.05 <0.005 <0.005
— 30 47 50
9
0 1.1 5.7 28.2 h
0 2.3 11.6 57.8
5 5 5 5
17.4 ± 6.4 18.2 ± 2.8 14.6 ± 4.5 0 ± 0
— >0.05 >0.05 <0.005
— NS NS 100
Cyclic Spermine Analogues (3,4,3)
10
0 1.2 6.1 30.5
0 2.3 11.6 57.8
5 5 5 5
18.6 ± 8.5 12.6 ± 4.8 11.6 ± 2.9 8.4 ± 1.5
— >0.05 >0.05 <0.05
— NS NS 55
11
0 1.6 8.0 16.0
0 2.3 11.6 23.2
5 5 5 5
16.2 ± 5.4 12.4 ± 2.1 13.6 ± 5.1 11.4 ± 2.1
— >0.05 >0.05 >0.05
— NS NS NS
12
0 0.03125 0.0625 0.125 0.25 g 0.5 g 0.99 g
0 0.0726 0.145 0.29 0.58 1.16 2.3
10 5 5 5 5 5 5
# 11.3 ± 4.1 5.4 ± 2.1 2.2 ± 1.3 0.6 ± 0.9 0 ± 0 0 ± 0 0 ± 0
— <0.005 <0.001 <0.001 <0.001 <0.001 <0.001
— 52 80 95 100 100 100
Longer Methylene Backbones
13
0 5 25
0 11.6 57.8
29 30 5
19.1 ± 6.4 2.1 ± 2.1 0 ± 0
— <0.001 <0.001
— 89 100
14
0 1.1 5.3 26.6
0 2.3 11.6 57.8
5 5 5 5
18.2 ± 8.2 13.2 ± 6.3 2.2 ± 3.3 0 ± 0
— >0.05 <0.005 <0.005
— NS 88 100
15
0 1.06 5.28 26.38
0 2.32 11.57 57.8
5 5 5 5
11.0 ± 4.8 8.8 ± 1.6 8.2 ± 3.1 2.0 ± 2.0
— >0.05 >0.05 <0.005
— NS NS 82
Unsymmetrical Methylene Backbones
16
0 1 5 25 i
0 2.31 11.56 57.8
5 5 5 5
13.2 ± 7.5 10.4 ± 5.2 9.4 ± 4.1 0.4 ± 0.9
— >0.05 >0.05 <0.01
— NS NS 97
17
0 1.06 i 5.32 i 26.6 i
0 2.32 11.56 57.8
5 5 5 5
8.8 ± 5.0 1.4 ± 1.9 0 ± 0 0 ± 0
— <0.05 <0.01 <0.01
— 84 100 100
a Polyamine analogues were administered SC to rats at the doses shown in the table. Thirty minutes later, the rats were subjected to stress, i.e., a cage filled with water to within 0.5 cm of the height of a 70 × 50 mm dish. Stool output was monitored for 6 h after commencement of the stress.
b Stool output is expressed as the number of fecal pellets excreted over the 6-h collection period.
c A one-tailed t-test assuming unequal variance was performed on the data of the treated vs control (0 mg/kg) animals for each compound. A value of P < 0.05 was considered significant.
d Percent reduction was calculated by dividing the mean value from the treated animals (T) by the mean value from the control animals (C), subtracting the resulting quotient from 1.0, and multiplying by 100 [i.e., (1.0 − T/C) × 100]. NS, not significant.
e Due to severe CNS toxicity, the experiment was stopped after 2 h; the results after 2 h are reported.
f All rats in this group died ˜24 h after drug administration.
g Toxic effects were evident, including huddling in the corner of the cage.
h Due to severe CNS toxicity, 3 of the 5 rats were removed after 4-4.5 h; neither of the remaining 2 rats had any stool output for the remainder of the study.
i The rats were quite lethargic, as though sedated, after drug administration.
TABLE 2
ACTIVITY OF POLYAMINE ANALOGUES WHEN
GIVEN ORALLY TO RATS a
Dose, kg −1
Stool
P-
%
Compound
mg
μmol
n
Output b
Value c
Reduction d
CHX(3,4,3)-trans
0
0
5
10.0 ± 2.9
—
—
1
2.3
5
9.0 ± 1.6
>0.05
NS
5
11.6
5
2.2 ± 1.3
0.001
78
10
23.2
5
2.0 ± 1.9
<0.001
80
DEHSPM
0
0
5
17.6 ± 3.9
—
—
50
115.6
5
10.6 ± 1.8
<0.01
40
DE(5,4,5)
0
0
10
19.1 ± 3.3
—
—
5.3
11.6
10
15.2 ± 8.5
>0.05
NS
10.6
23.2
10
8.6 ± 4.9
<0.001
55
26.6
57.8
10
5.1 ± 3.1
<0.001
73
a Polyamine analogues were administered to rats PO by gavage at the doses shown in the table. Thirty minutes later, the rats were subjected to stress, i.e., a cage filled with water to within 0.5 cm of the height of a 70 × 50 mm dish. Stool output was monitored for 6 hr after commencement of the stress.
b Stool output is expressed as the number of fecal pellets excreted over the 6-hr collection period.
c A one-tailed t-test assuming unequal variance was performed on the data of the treated vs control (0 mg/kg) animals for each compound. A value of P < 0.05 was considered significant.
d Percent reduction was calculated by dividing the mean value from the treated animals (T) by the mean value from the control animals (C), subtracting the resulting quotient from 1.0, and multiplying by 100 [i.e., (1.0 − T/C) × 100]. NS, not significant.
It is thus established, therefore, that the compounds described herein are useful for the treatment of irritable bowel disease (IBD) or syndrome (IBS).
The method and composition of the present invention are predicated on administering to a subject (human or animal) suffering from irritable bowel disease an effective amount of one or more of the compounds described herein as being effective therefore. Administration may be accomplished either therapeutically or prophylactically by means of pharmaceutical compositions which are prepared by techniques well known in the pharmaceutical sciences.
While the compounds of the invention are preferably administered orally or intrarectally, they may also be administered by a variety of other routes such as transdermally, subcutaneously, intranasally, intramuscularly and intravenously. The present invention is also directed to pharmaceutical compositions which include at least one compound as described above in association with one or more pharmaceutically acceptable diluents, excipients or carriers therefor. In making the pharmaceutical compositions of the present invention, one or more compounds will usually be mixed with, diluted by or enclosed within a carrier which may be in the form of a capsule, sachet, paper or other container. When the carrier serves as a diluent, it may be a solid, semi-solid or liquid material which acts as a vehicle, excipient or medium for the active ingredient. Thus, the compositions can be in the form of tablets, pills, powders, lozenges, sachets, cachets, elixirs, suspensions, emulsions, solutions, syrups, aerosols (as a solid or in a liquid medium), ointments containing, for example, up to 60% by weight of active compound, soft and hard gelatin capsules, suppositories, sterile injectable solutions and sterile packaged powders.
Some examples of suitable carriers, excipients and diluents include lactose, dextrose, sucrose, sorbitol, mannitol, starches, gum acacia, calcium phosphate, alginates, tragacanth, gelatin, calcium silicate, microcrystalline cellulose, polyvinylpyrrolidone, cellulose, water, syrup, methyl cellulose, methyl- and propyl-hydroxybenzoates, talc, magnesium stearate and mineral oil. The formulations can additionally include lubricating agents, wetting agents, emulsifying and suspending agents, preserving agents, sweetening agents or flavoring agents. The compositions of the invention may be formulated so as to provide rapid, sustained or delayed release of the active ingredient after administration to the patient by employing procedures well known in the art.
The dose of the compound is that amount effective to prevent occurrence of the symptoms of the disease or to treat some symptoms of the disease from which the patient suffers. By “effective amount,” “therapeutic amount” or “effective dose” is meant that amount sufficient to elicit the desired pharmacological or therapeutic effects, thus resulting in effective prevention or treatment of the disease. Prevention of the disease is manifested by a prolonging or delaying of the onset of the symptoms of the disease. Treatment of the disease is manifested by a decrease in the symptoms associated with the disease or an amelioration of the recurrence of the symptoms of the disease.
The effective dose may vary, depending upon factors such as the condition of the patient, the severity of the symptoms of the disease and the manner in which the pharmaceutical composition is administered. The compositions are formulated, preferably in a unit dosage form, such that each dosage contains from about 0.006 to about 12,000 mg, more usually about 0.06 to about 6,000 mg, of the active ingredient. The term “unit dosage form” refers to physically discrete units suitable as unitary dosages for human subjects and other mammals, each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect, in association with one or more of the above-described suitable pharmaceutical diluents, excipients or carriers.
The compounds are effective over a wide dosage range in treating IBD. Thus, as used herein, the term “effective amount” refers to a dosage range of from about 0.006 to about 500 mg/kg of body weight per day. In the treatment of adult humans, the range of about 0.06 to about 250 mg/kg, in single or divided doses, is preferred. However, it will be understood that the amount of compound actually administered will be determined by a physician in light of the relevant circumstances, including (1) the condition to be treated, (2) the choice of compound to be administered, (3) the chosen route of administration, (4) the age, weight and response of the individual patient, and (5) the sever of the patient's symptoms. Therefore, the above dosage ranges are not intended to limit the scope of the invention in any way.
By “active ingredient” is meant a polyamine as described herein or a salt thereof with a pharmaceutically acceptable acid. By “salt” is meant an addition salt between the polyamine of the invention and a sufficient amount of pharmacologically appropriate acid, such as hydrochloric, sulfuric, phosphoric, acetic, butyric, citric, maleic, lactic, valeric, tartaric, gluconic, succinic and the like, made by conventional chemical means. | A method and composition for treating irritable bowel syndrome in a subject in need of such treatment, utilizing an amount of a polyamine having the formula:
R—NH—(CH 2 ) a —NH—(CH 2 ) b H—(CH 2 ) c —NH 2 , 1 )
CF 3 —C 6 H 5 —(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —NH—(CH 2 ) d NH—(CH 2 ) e —C 6 H 5 —CF 3 , 2 )
R—NH—(CH 2 ) a —NH—C 6 H 6 —NH—(CH 2 ) b —NH—R 3 )
and
PIP—(CH 2 ) a —NH—(CH 2 ) b —NH—(CH 2 ) c —PIP, 4 )
wherein:
R is alkyl, aryl, aralkyl, alkaryl, or cyclo-alkyl having up to about 10 carbon atoms, and any of the alkyl chains may optionally be interrupted by at least one etheric oxygen atom,
PIP is piperidine and
a, b, c, d, and e may be the same or different and are integers from 1-10 effective to treat irritable bowel syndrome. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to flow control devices for solid particulate materials and more specifically to a flow control apparatus for feeding recycled particulate solid material at a controlled flow rate into a fluidized bed combustion vessel from an external heat exchanger. In general, the invention is concerned with a flow control apparatus for use in feeding solid particulate material at selected flow rates over substantial distances from a supply point to an injection point wherein the material is delivered into a vessel for further treatment and handling.
One novel aspect of the invention resides in the formation of a column or head of the material in a standpipe or similar chamber to provide a continuously present seal of material between a supply or source vessel and a receiving or output vessel so that the respective vessels may be maintained at operating pressures independent of one another. The flow rate of material can also be maintained at a selected rate independent of the operating pressure of the vessels involved. Moreover, a flow control device in accordance with the present invention eliminates the need for mechanical valve elements and requires no moving parts to provide the valving flow control action. The flow control device of the present invention is especially well adapted and designed for controlled feeding of recycled particulate solid materials into a fluidized bed combustion vessel from an external heat exchanger. The flow control device is also useful for a wide variety of other applications wherein solid particulate material is involved.
2. Description of the Prior Art
In multi-solid fluidized bed steam generating systems such as disclosed in U.S. Pat. Nos. 4,084,545 and 4,154,581 heating devices known as "L-valves" have been provided for recycling solid particulate material back into a dense fluidized bed in a combustion vessel from a supply source such as a cyclone type separator. A problem associated with such L-valves often occurs when the length of a horizontal feeder conduit or horizontal leg of an L-valve is too great so that the material tends to stagnate or plug up and block off flow through the horizontal leg of the L-valve. Moreover, some types of materials are extremely difficult to move through a lengthy horizontal flow conduit into a remote vessel. Because of these problems, the spacing or distance between the source of recycled fines and the combustion vessel has been limited or in the alternative, mechanical feeders having moving parts and high energy requirements were necessitated. Another problem associated with conventional L-valves is the requirement for a sloping feed conduit rather than a horizontal leg when the distance between the supply of recycled solid material and the combustion vessel become too great to be accommodated with a horizontally extended feeder conduit. In any case, the lack of a suitable flow controllable, feeding device for solid particulate material results in design constraints on the positioning and placement of components in a steam generating system which are undesirable.
OBJECTS OF THE PRESENT INVENTION
Accordingly, it is an object of the present invention to provide a new and improved flow control device for solid particulate material and more specifically a flow control device of the character described which provides reliable operation at a wide variety of selected flow rates, even with a horizontal feeder conduit of relatively great length without fear of plugging or stagnation of material in the feeder conduit.
Another object of the invention is to provide a new and improved flow control device of the character described which requires no moving parts and which establishes a continuous material seal between a source vessel and a receiving vessel so that the vessels can be operated at pressures independent of each other.
Another object of the present invention is to provide a new and improved flow control device of the character described which is particularly well suited for feeding solid particulate materials from one vessel to another in which the flow can be started and stopped at will with little fear of plugging up.
BRIEF DESCRIPTION OF THE INVENTION
The foregoing and other objects and advantages of the present invention are accomplished in an illustrated embodiment herein which comprises and new and improved flow control device for solid particulate material especially adapted for feeding the material from a source vessel to a receiving vessel at selectively controllable flow rates. The flow control device includes an elongated generally horizontal material feeder conduit or leg having an outlet end in communication with the receiving vessel and a receiving end remote therefrom. An upstanding material collector conduit or leg is provided having a lower end in communication with the receiving end of the feeder leg and an upper end of the material collector leg is adapted to receive a flow of solid particulate material from a source vessel such an external heat exchanger or cyclone type solids separator.
The upstanding collector conduit is dimensioned to provide a standpipe adapted to retain a quantity of the solid particulate material thereby establishing a pressure sealing head of material to seal between the respective vessels. The vessels may be operated at substantially different operating pressures without adversely affecting the feeding or flow of material from the source vessel to the receiving vessel. A gas assisted flow initiator and controller is extended into the horizontal feeder conduit or leg and directs a controlled flow of pressurized gas into the solid particulate material fluidizing the material and initiating travel along the leg into the receiving vessel such as a fluidized bed of a combustion vessel. The gas which is injected into the solid particulate material may comprise air or gaseous products of combustion and the injected gas may have an injection pressure greater than that obtaining in the feeder conduit or the vessels. The injected gas is effective to fluidize the material in the horizontal feeder leg so that the head of material contained in the upstanding collector leg or standpipe is sufficient to cause the material to flow in a fluidized state into the receiving vessel. When the gas is turned down, the material flow is reduced or stopped altogether and the material itself provides a seal or shut-off valving action between the supply and receiving vessels.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference should be had to the following detailed description taken in conjunction with the drawings, in which:
FIG. 1 is an elevational vertical cross-sectional view of a multi-solid fluidized bed steam generating system utilizing flow control devices constructed in accordance with the features of the present invention;
FIG. 2 is an enlarged, fragmentary vertical cross-sectional view of a flow control device for feeding solid particulate material from a supply source to a receiving vessel constructed in accordnce with the features of the present invention;
FIG. 2A is a transverse, vertical cross-sectional view taken through a horizontally extending feeder conduit or leg of the flow control device of FIG. 2 at lines 2A--2A;
FIG. 2B is a transverse cross-sectional view of an alternate embodiment of a feeder conduit taken on a cross-sectional plane similar to that of FIG. 2A;
FIG. 3 is a vertical elevational view of another embodiment of a flow control device constructed in accordance with the features of the present invention;
FIG. 3A is a transverse cross-sectional view taken substantially along lines 3A--3A of FIG. 3;
FIG. 3B is a transverse cross-sectional view of an alternate embodiment of a horizontal feeder conduit or leg taken on a cross-sectional plane similar to that of FIG. 3A; and
FIG. 4 is a schematic elevational view of a storage and transport system for feeding solid particulate material from a first vessel to a second vessel employing flow control feeder devices in accordance with the features of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to the drawings, in FIG. 1 is illustrated a multi-solid fluidized bed steam generating system 10 utilizing one or more flow control devices 12 for recycling solid particulate material 14 such as hot sand and the like from an external heat exchanger vessel 16 back to a dense bed section 18 of a vertically extending combustion vessel 20. The combustion vessel 20 includes a frusto-conical lower end section 22 with a drain valve 24 at the lower end and a primary source of combustion air is introduced at a level intermediate the frusto-conical section 22 and dense bed section 18 through a plurality of air injector conduits 26 interconnected by one or more supply headers 28 on opposite sides of the combustion vessel and supplied with primary fluidizing combustion air from a suitable source such as a large blower 30 indicated in schematic form in FIG. 1.
Primary air supplied under pressure from the blower 30 moves upwardly through the dense bed section 18 and fluidizes the permanently residing, relatively large size particles of the bed to continuously move around within the bed to effectively transfer heat to the incoming primary combustion air. Fuel for combustion in the form of pulverized coal and/or natural gas along with an additive such as limestone is introduced downwardly adjacent an upper level of the dense bed section 18 via a sloping fuel inlet conduit 32. An intense combustion process takes place in the upper regions and above the dense bed section 18 and the recirculating multi-solid fines 14 absorb the heat of combustion to maintain a controlled maximum temperature as the finer solid material particles move upwardly from the dense bed towards the upper end of the combustion vessel 20.
These recirculating solid particulate material fines may comprise inert refractory material such as sand and include non-burned fuel particles and limestone. The fine solids are mixed with the hot combustion gases and generally flow upwardly from the dense bed region 18 forming a dust space or cloud wherein further combustion and heat absorption by the fines takes place over a substantial height in the combuston vesesl 20 extending from the upper levels of the dense bed to a dome-shaped top 34 at the upper end of the vessel.
Additional secondary combustion air is introduced into the combustion vessel at a level spaced above the fuel conduit 32 through a plurality of radial secondary air injector conduits 36 which are supplied from a ring manifold 38 supplied with secondary air under pressure from a source such as a large blower or fan 40 shown schematically in FIG. 1. Additional heated gas and recycled fine material is supplied to the combustion vessel 20 at a level above the secondary air inlets 36 through an inlet conduit 42 connected to a hood structure 44 above the external heat exchanger 16.
The hot gaseous products of combustion along with solid particulate material including inert fines and unburned or partially burned coal particles and limestone particles pass upwardly to the upper end of the combustion vessel 20 and move radially outwardly through an outlet 46 into a tangentially directed inlet 48 of a cyclone or separator vessel 50 utilizing centrifugal force to separate out the solids from the gaseous products so that the gases flow upwardly through an outlet 52 while the solids fall downwardly into a frusto-conical lower cyclone section 54 having an outlet at the lower end in communication with a hot chamber 56 of the external heat exchanger 16.
The hot gaseous products of combustion leaving the outlet 52 of the cyclone type centrifugal separator 50 flow through a hot gas duct 58 to enter the inlet side of a gas heated convection tube pass 60. The boiler tubes of the convection pass are contained within an insulated housing 62 having an outlet for gas in communication with an exhaust gas duct 64 leading to bag house filters or gas scrubbers before the cleansed gas is finally discharged into the atmosphere.
The convection tube pass housing 62 contains a steam drum 66 at an upper level above the gas outlet 64 and a back of boiler tubes 68 extends downwardly from the steam drum to a mud drum 70 at a level below the gas outlet. Hot water from the mud drum flows down an inlet pipe 72 to a circulating pump 74 and is discharged from the pump through a pressure line 76 connected to a header system 78 of the external heat exchanger 16.
Additional heat is picked up by the hot water as it passes from the header system 78 through a heat exchanger coil 80 provided in a secondary (cooler) chamber 82 of the external heat exchanger 16. The chamber 82 is separated from the hot chamber 56 by a dam 84 and some of the fluidized fines returned to the hot chamber from the outlet 54 of the cyclone 50 flow over the dam into the cooler chamber to give up heat to the water flowing through the coil 80.
After passing through the coil 80, the hot water and steam flows upwardly to a collection header system 86 at an upper level of the external heat exchanger 16, and then flows through a conduit 88 connected to a lower header system 90 at a lower level in the convection pass housing 62. The heated water/steam then flows upwardly through risers 92 to an upper steam header 94 and from the steam header 94 to the steam drum 66 through a steam line 96.
Superheated steam is provided by a superheater tube bank 98 positioned adjacent the hot gas inlet side of the housing 62 and steam is supplied to the superheater coil 98 via a conduit 100 from the steam drum as illustrated. Superheated steam generated in the superheater coil 98 passes upwardly to a collection header 102 and out of the housing for use through a superheated steam output line or conduit 104.
In accordance with the present invention, the hot solid particulate materials separated from the hot gaseous products of combustion in the cyclone centrifugal separator 50 flow downwardly to the hot chamber 56 of the external heat exchanger 16 and in the hot chamber fluidizing air is supplied to fluidize the solids via air inlet headers 106 extending into the lower level of the hot chamber and supplied from a blower 108 through a air duct inlet 110. Some of the heavier particles of material pass directly downwardly from the lower end of the hot chamber 56 into the upper flow control device 12 for recirculation back into the dense bed section 18 of the combustion vessel 20. A portion of the hot solid particulate material reaching the hot chamber 56 however, flows over the dam 84 into the cooler recycle chamber 82 to give up heat to the coil 80. This solid material is colled by giving up heat to the water/steam in the coil 80 and eventually flows downwardly into a discharge hopper 112 below the main body of the external heat exchanger. The hopper 112 has a lower outlet end in communication with the lower flow control device 12 to supply colder solid particulate material thereto for recycling into the dense bed 18 of the combustion level at a low level therein. The hot solid material particulate material reaching the cool chamber 82 around the coil 80 is maintained in a fluidized state by a plurality of air injection headers 114 provided in an array adjacent a bottom level of the chamber and these headers are also supplied with a source of pressurized air from the conduit 110 and blower 108. Some of the fines solid particles are carried upwardly by the fluidizing gas into the hood 44 and are recycled into the combustion vessel 20 through the inlet 42.
Referring now to FIG. 1 and particularly to FIGS. 2 and 2A, each of the new and improved L-valves or flow control devices 12 is adapted to provide an adjustably controllable flow and valve action for recycling solid particulate material 14 that is discharged from the external heat exchanger 16 back into the dense bed section 18 of the combustion vessel 20. The feeder 12 includes an elongated, hollow, tubular, generally horizontally extending conduit or feeder leg 116 provided with a steel outer shell 116a and lined with an inner refractory material 116b. As illustrated in FIG. 2A, the heater conduit 116 has a circular transverse cross-section but if desired, as shown in FIG. 2B, the feeder conduit may also be provided with a square or rectangular transverse cross-section. The conduit includes an outlet end 118 adapted to communicate with the interior of the combustion vessel 20 so that solid particulate material 14 will be injected into the fluidized dense bed material at a level intermediate the upper and lower surface of the dense bed section. The feeder conduit 116 also includes an opposite or receiving end 120 spaced outwardly remote from the outlet or discharge end 118.
In accordance with the invention, the feeder conduit may be horizontal or near horizontal in alignment and can be of an indeterminate length so that close proximity between the combustion vessel 20 and the external heat exchanger 16 is not a limiting requirement. As will be noted in FIG. 2, the solid particulate granular material 14 has an angle of repose indicated by the dotted line 122 and the horizontal length of the feeder leg is substantially in excess of a distance between the inlet end 120 and a point where the lower end of the line 122 representing the angle of repose strikes the lower inside surface of the feeder conduit. Heretofore in L-valves it was difficult to obtain good flow characteristics when the length of the horizontal leg of the L-valve was substantially greater than the distance prescribed by the natural angle of repose striking the lower surface of the horizontal leg.
The feeder or flow control device 12 also includes an upstanding generally vertically extending leg 124 formed with an outer steel jacket 124a and lined with a refractory heat resistant material liner 124b. The upstanding leg 124 includes an upper receiving end in communication with the discharge outlet of the hot recycle chamber 56 of the external heat exchanger 16 or with the outlet at the lower end of the cooler recycle chamber 86 and its discharge hopper 11 as shown in FIG. 1. Material received in the upstanding leg 124 of the flow control devices 12 tends to accumulate in an upwardly extending column to form a standpipe-like head of material which forms a pressure seal between the receiving end of the standpipe leg 124 and the outlet or discharge end of the horizontal feeder leg 116. Accordingly, the operating pressure of the dense bed section 18 in the combustion vessel 20 is not dependent on the operating pressure which obtains in the external heat exchanger 16 so as to adversely effect the operating characteristics of either of the components. The height of material 14 in the vertical or standpipe leg 124 also provides a continuous downward bias or head tending to direct the material dowards toward the receiving end 120 of the horizontal feeder conduit 116 when flow commences.
The material 14 contained in the flow control device 12 is fluidized and flow is initiated and regulated by the injection of pressurized gas such as air introduced from an elongated gas injector conduit 126 having a plurality of longitudinally and radially spaced apart gas injector openings 126a provided on a lower portion thereon as best shown in FIGS. 2A and 2B. The fluidizing air or gas is injected into the feeder conduit 116 under a slight amount of pressure so as to turbulently mix and fluidize the solid particulate material 14 therein ready for movement in horizontal flow toward the discharge end 118 in communication with the dense bed section 18. The air injector conduit 126 is provided with a cap 126b at the outer end adjacent the dense bed section 18 so that the fluidizing gas or air is introduced over substantially the entire length of the conduit 116 to maintain the solid particulate material 14 in a fluidized state.
Pressurized gas or air for initiating and controlling the material flow is also introduced into the upstanding standpipe portion 124 at an elevated level via a conduit 128 having an outlet 128a opening into the interior of the standpipe at a level just above the receiving end 120 of the horizontal leg 116 as illustrated in FIG. 2. The pressurized gas introduced into the flow control device 12 through the upper injector 128 causes the material to move initially after flow has been stopped and thereafter with a controlled flow rate along the horizontal conduit 116. It has been found that a small amount of pressurized gas introduced through the upper injector conduit 128 is highly effective in regulating precisely the volume flow rate of material recycled back into the combustion vessel 20 and in controlling the starting and stoppage of flow as desired. Because the level of the upper air injector conduit 128 is relatively low in relation to the upper level or head of material 14 in the upstanding standpipe leg 124 most of the gas injected flows downwardly into the horizontal feeder leg 116 rather than upwardly from the point of injection through the material seal provided by the column of material. Accordingly, injection of gas or air under pressure from both of the injector conduits 126 and 128 has little effect on the operating air or gas pressure in either the external heating exchanger 16 or the combustion vessel 20.
For precision control and convenience in starting and stopping the flow of material 14 and for regulating the flow rate thereof, the flow of injected gas in the respective air injector conduits 126 and 128 is regulated and meters 130 are provided downstream of flow control valves 132 (FIG. 1) which are operative to control the flow of injected gas into the system or to shut off the flow entirely to the flow control devices 12. Pressurized gas is usually supplied to the injector conduits 126 and 128 from a suitable source such as a compressed air tank 134 or a manifold supplied with compressed gas by a pump or blower 136 as shown in FIG. 1. At the lower end of the vertical leg or standpipe 124 of the flow control devices 12, there is provided an end wall segment 138 with an opening therein and a clean out plug 140 which can be removed as desired for cleaning out material when required.
Referring now to FIGS. 3, 3A and 3B, therein is illustrated a modified form of flow control device referred to generally by the reference numeral 212. Corresponding components of the device 212 which are substantially the same or identical to those in the prior embodiment are provided with an additional prefix reference numeral 2 and will not be described in detail. In accordance with the invention, the flow control device or feeder valve 212 is provided with a modified lower gas injector system referred to generally by the reference numeral 242 and comprising a hollow plenum chamber 244 formed adjacent the bottom of the horizontal feeder leg 216. The plenum chamber 244 is provided with a flat top wall 246 of steel or suitable metal having a plurality of gas injector openings 246a spaced along the length thereof for injecting fluidizing gas under pressure into the material 14. The plenum 244 is provided with an outlet end wall 248 adjacent the outlet end 218 of the horizontal feeder conduit 216 and an inlet end wall 250 is provided adjacent the receiving end 220 of the horizontal feeder leg. The perforations or openings 246a in the upper wall 246 of the plenum chamber 244 provide a fluidizing action on the material 14 over a large area so that the injection of flow initiating and regulating gas from the conduits 126 and 128 is highly effective to move the material along the conduit 216 into the dense bed section 18 of the combustion vessel 20. Precision control of the flow rate of material 14 is achieved by regulating the pressure and flow of the gas injected through the conduits 126 and 128 by means of the meters 130 and control valves 132 provided in the lines.
While the flow control devices 12 and 212 herein described have been utilized in multi-solid fluidized bed steam generation systems as set forth in this disclosure, these devices also have utility in a wide range of applications wherein different types of solid materials in particulate or granular form other than sand or inert materials used in the system 10 are provided. Referring now specifically to FIG. 4, a material transport system 310 is illustrated in somewhat diagrammatic or schematic form to include a plurality of flow control devices 12 or 212 in accordance with the present invention for moving granular or particulate solid material from a first vessel 312 to a second vessel 314 and on to successive vessels or locations by virtue of a discharge conduit 316. Solid material may be delivered by gravity or otherwise through an inlet conduit 318 for storage or containment in the vessel 312. This material flows out of the lower end of the vessel into the receiving end of the standpipe leg of a flow control device 12 or 212 in communication therewith. The material is directed into the second vessel 314 via an outlet conduit 320 in fluidized form and the material may be added to or combined with additional materials supplied to the vessel 314 by an inlet chute 322. The mixed material in a fluidized state then passes downwardly through the outlet end at the lower end of the vessel 314 into a flow control device 12 or 212 and is fed out at a controlled flow rate through the delivery conduit 316 to a remote location. In the system 310 as illustrated in the diagram of FIG. 4, a wide variety of materials may be utilized and exceptionally long distances between the successive vessels 312 and 314 may be tolerated while still providing an accurately controllable flow of material.
Although the present invention has been described in terms of a preferred embodiment, it is intended to include those equivalent structures, some of which may be apparent upon reading this description, and others that may be obvious after study and review. | A flow control device for solid particulate material such as recycled granular solids utilized in a fluidized bed combustion vessel includes a generally horizontal material feeder conduit having an outlet end in communication with the fluidized bed of the combustion vessel and a receiving end remote therefrom. An upstanding material collector conduit having a lower end in communication with a receiving end of the feeder conduit is provided and an upper end of the collector conduit is adapted to receive a flow of particulate solid material to be fed at a controlled flow rate into the combustion vessel. The upstanding collector conduit forms a standpipe for retaining a quantity of material to establish a pressure sealing head or column of material extending upwardly of the receiving end of the feeder conduit. A gas assisted flow initiator and controller extends into the feeder conduit for directing a flow of pressurized gas into the solid particulate material to fluidize the same for travel into the combustion vessel at a selected flow rate. | 5 |
BACKGROUND OF INVENTION
The present invention relates generally to medical imaging data acquisition and graphical user interfaces and, more particularly, to a method and apparatus for managing the prescription workflow of a medical imaging session and acquiring medical images in accordance with this managed workflow.
The present invention is directed to the management of workflow for the prescription, acquisition and post processing of medical imaging sessions. The invention is particularly useful in prescribing MR image acquisition. While known MR systems somewhat guide a user or MR technologist through the imaging session, there is a need for a workflow management tool that is more logical and intuitive than these known systems. Prescribing MR imaging sessions and/or experiments involves setting parameters that are used by the pulse sequence, in reconstruction, and the visualization systems to acquire MR imaging data. The number of parameters is often extensive and with these known systems there is insufficient logic, layout, and management to guide the user from one parameter to the next. These workflow tools are often singular, parameter intensive, not intuitive, complex, and not configurable.
Known workflow tools can take the form of a graphical user interface (GUI) that appears on the operating console of the MR system. These GUIs typically provide all the scan parameters to the user simultaneously, but with only a limited number of application-specific parameters. These parameters are grouped into logical clusters and presented to the user. However, the clusters of scan parameters are presented on the GUI in such a manner that does not generally support generalized, logical workflow. Further, these known systems often fail to provide a mechanism to logically guide the user from one set of parameters to the other. These systems tend to support workflow where the user input actions occur randomly over the screen instead of following a sequential, logical approach. In addition, since all of the scan parameters are presented to the user in a single window, the window often appears complex and congested which contributes to user confusion and potential input errors. These known workflow systems are commendable across the entire spectrum of MR applications however, there is a need for a GUI that is tailored to a particular clinical or research application. That is, there is a need for a GUI that reflects the MR application currently running.
Typically, the workflow for these MR systems is restricted to presenting all scan parameters and associated application features on a single GUI presentation. As a result, the GUI does not efficiently guide the user through application prescription or acquisition, does not provide application information, lacks modularity, is not configurable, and introduces unnecessary complexity for prescribing MR experiments and acquiring MR images.
Therefore, it would be desirable to design a method and apparatus for managing the workflow for prescribing MR imaging sessions and experiments that would be adaptable to a particular MR application and be intuitive and logical in the presentation of prescription parameters.
BRIEF DESCRIPTION OF THE INVENTION
The present invention is directed to a method and apparatus that streamlines the process of prescribing and acquiring MR experiments and MR data processing applications. The present application further provides a modular intuitive and guided workflow having a graphical user interface (GUI) that may be tailored and made singular and unique for each individual application. The GUI recognizes the general principle that user activity begins in the upper left-hand portion of the screen and proceeds horizontally across the screen moving from left to right and top to bottom. The GUI incorporates a number of tabs wherein each tab corresponds to a major prescription or image post-processing step. The tabs are aligned vertically along the left side of the screen, although they may optionally be aligned horizontally across the top of the screen, and are used to modularize the application workflow. These tabs lead the user through the steps necessary to prescribe the application as well as give the user valuable information regarding the purpose of each step via a tab label. Status indicators corresponding to each tab are also provided to convey the state of the activities associated with each tab, whether or not the tab has been selected, or if the associated task was completed successfully or not. The GUI also makes available user messages, scan information, and a list of the components necessary for the user to quickly initiate scan activity. The GUI also conveys the state of the current application and allows for the user to determine if the current application is able to scan, if another application is currently scanning, scan times, as well as other important scan information.
Therefore, in accordance with one aspect of the present invention, a GUI is provided for prescribing medical imaging sessions, acquiring medical images, and processing imaging data. The GUI comprises a plurality of modularizing selectors configured to facilitate workflow through a medical imaging application. A plurality of status indicators are also provided wherein each status indicator corresponds with a modularizing selector and configured to display at least one of selection of the modularizing selector and completion of tasks associated with the modularizing selector. The GUI further includes a messaging module configured to automatically display messages regarding the medical imaging application.
In accordance with another aspect of the present invention, a graphical workflow management tool is provided for prescribing an imaging scan. The tool includes a GUI configured to be visually displayed on a console of a medical imaging system. The tool further includes a plurality of prescription tabs aligned vertically on the GUI. A plurality of status indicators are also provided on the GUI wherein each indicator is configured to display a status of activities for a corresponding prescription step. The tool further includes a plurality of tabs aligned horizontally on the GUI that upon selection display a context-specific user interface.
In yet another aspect of the present invention, an apparatus includes a computer programmed to receive a launch application command and launch the application in response thereto. The computer is further programmed to receive a number of application steps identifier. The computer is further programmed to display a GUI on a console the GUI having a number of tabs equal to the number of identified application steps. Each tab corresponds to an interaction performed by a user, such as prescription, scanning, etc. The computer is also programmed to display the status of application steps. The computer is also programmed to receive another prescription command and acquire images in response to the received another application step.
In a further aspect of the present invention, a method of acquiring images is provided and includes receiving a launch application instruction and launching the application. The method further includes determining a number of prescription steps based on a received user input. The method also includes displaying a GUI for prescribing an imaging session. The GUI is configured to include a number of modularizing tabs wherein each modularizing tab represents a prescription step.
Various other features, objects and advantages of the present invention will be made apparent from the following detailed description and the drawings.
BRIEF DESCRIPTION OF DRAWINGS
The drawings illustrate one preferred embodiment presently contemplated for carrying out the invention.
In the drawings:
FIG. 1 is a schematic block diagram of an MR imaging system for use with the present invention.
FIG. 2 is a representation of a graphical user interface illustrating the allocation of screen space in accordance with the present invention.
FIG. 3 is a representation of graphical user interface similar to that shown in FIG. 2 illustrating allocation of screen space in an alternate embodiment of the present invention.
FIG. 4 is a representation of a graphical user interface for setting up initial scan application parameters for one representative medical imaging application in accordance with the present invention.
FIG. 5 is a representation of a graphical user interface similar to that shown in FIG. 4 for prescribing localizers for the representative medical imaging application in accordance with the present invention.
FIG. 6 is a representation of a graphical user interface for the inputting of patient information in accordance with the present invention.
FIG. 7 is a representation of a graphical user interface for prescribing and acquiring images in accordance with the present invention.
FIG. 8 is a representation of a pop-up dialog for use with the present invention.
FIG. 9 is a representation of a graphical user interface for displaying images of a scan station.
FIG. 10 is a representation of a graphical user interface for displaying summary data for the representative medical imaging application in accordance with the present invention.
FIG. 11 is a representation of a graphical user interface for prescribing a particular medical imaging application in accordance with the present invention.
FIG. 12 is a representation of a graphical user interface for acquiring medical diagnostic image for the representative medical imaging application in accordance with the present invention.
FIG. 13 is a representation of a pop-up dialog for use with the present invention.
FIG. 14 is a representation of a graphical user interface for setting up advanced scan settings for the representative medical imaging application in accordance with the present invention.
FIG. 15 is a representation of a graphical user interface for displaying help topics for the representative medical imaging application in accordance with the present invention.
FIG. 16 is a representation of a graphical user interface for displaying protocol information for the representative medical imaging application in accordance with the present invention.
FIG. 17 is a representation of a graphical user interface for modifying scan time in accordance for the representative medical imaging application with the present invention.
FIG. 18 is a representation of a graphical user interface for modifying the resolution for the representative medical imaging application in accordance with the present invention.
FIG. 19 is a representation of a graphical user interface for modifying the contrast for the representative medical imaging application in accordance with the present invention.
FIG. 20 is a representation of a graphical user interface for modifying the signal to noise ratio for the representative medical imaging application in accordance with the present invention.
FIG. 21 is a representation of a graphical user interface for modifying slice information for the representative medical imaging application in accordance with the present invention.
DETAILED DESCRIPTION
Referring to FIG. 1 , the major components of a preferred magnetic resonance imaging (MRI) system 10 incorporating the present invention are shown. The operation of the system is controlled from an operator console 12 which includes a keyboard or other input device 13 , a control panel 14 , and a display 16 . The console 12 communicates through a link 18 with a separate computer system 20 that enables an operator to control the production and display of images on the screen 16 . The computer system 20 includes a number of modules which communicate with each other through a backplane 20 a . These include an image processor module 22 , a CPU module 24 and a memory module 26 , known in the art as a frame buffer for storing image data arrays. The computer system 20 is linked to disk storage 28 and tape drive 30 for storage of image data and programs, and communicates with a separate system control 32 through a high speed serial link 34 . The input device 13 can include a mouse, joystick, keyboard, track ball, touch activated screen, light wand, voice control, or any similar or equivalent input device, and may be used for interactive geometry prescription.
The system control 32 includes a set of modules connected together by a backplane 32 a . These include a CPU module 36 and a pulse generator module 38 which connects to the operator console 12 through a serial link 40 . It is through link 40 that the system control 32 receives commands from the operator to indicate the scan sequence that is to be performed. The pulse generator module 38 operates the system components to carry out the desired scan sequence and produces data which indicates the timing, strength and shape of the RF pulses produced, and the timing and length of the data acquisition window. The pulse generator module 38 connects to a set of gradient amplifiers 42 , to indicate the timing and shape of the gradient pulses that are produced during the scan. The pulse generator module 38 can also receive patient data from a physiological acquisition controller 44 that receives signals from a number of different sensors connected to the patient, such as ECG signals from electrodes attached to the patient. And finally, the pulse generator module 38 connects to a scan room interface circuit 46 which receives signals from various sensors associated with the condition of the patient and the magnet system. It is also through the scan room interface circuit 46 that a patient positioning system 48 receives commands to move the patient to the desired position for the scan.
The gradient waveforms produced by the pulse generator module 38 are applied to the gradient amplifier system 42 having G x , G y , and G z amplifiers. Each gradient amplifier excites a corresponding physical gradient coil in a gradient coil assembly generally designated 50 to produce the magnetic field gradients used for spatially encoding acquired signals. The gradient coil assembly 50 forms part of a magnet assembly 52 which includes a polarizing magnet 54 and a whole-body RF coil 56 . A transceiver module 58 in the system control 32 produces pulses which are amplified by an RF amplifier 60 and coupled to the RF coil 56 by a transmit/receive switch 62 . The resulting signals emitted by the excited nuclei in the patient may be sensed by the same RF coil 56 and coupled through the transmit/receive switch 62 to a preamplifier 64 . The amplified MR signals are demodulated, filtered, and digitized in the receiver section of the transceiver 58 . The transmit/receive switch 62 is controlled by a signal from the pulse generator module 38 to electrically connect the RF amplifier 60 to the coil 56 during the transmit mode and to connect the preamplifier 64 to the coil 56 during the receive mode. The transmit/receive switch 62 can also enable a separate RF coil (for example, a surface coil) to be used in either the transmit or receive mode.
The MR signals picked up by the RF coil 56 are digitized by the transceiver module 58 and transferred to a memory module 66 in the system control 32 . A scan is complete when an array of raw k-space data has been acquired in the memory module 66 . This raw k-space data is rearranged into separate k-space data arrays for each image to be reconstructed, and each of these is input to an array processor 68 which operates to Fourier transform the data into an array of image data. This image data is conveyed through the serial link 34 to the computer system 20 where it is stored in memory, such as disk storage 28 . In response to commands received from the operator console 12 , this image data may be archived in long term storage, such as on the tape drive 30 , or it may be further processed by the image processor 22 and conveyed to the operator console 12 and presented on the display 16 .
The present invention is directed to a method and apparatus of directing workflow for medical imaging experiments and sessions. The invention utilizes an hierarchical scheme to facilitate improved workflow. The workflow tool will be described with respect to a Peripheral Vascular (PV) application using MR imaging technology which is considered the “super” application because it is defined by the combination of multiple sub-applications. The teachings of this invention are not limited, however, to a PV application or MR technology. The PV application of the present invention varies from a traditional application of known MR systems. Specifically, the PV application is a combination of a 2D gradient echo application and a 3DSPGR (Three-Dimensional with Spoiled Gradient Echo Pulse Sequence) application. Therefore, the PV application GUI is a composition of the components that it defines as well as the components from other “sub” applications. The present invention includes a GU 100 designed to dynamically adjust the layout and distribution of screen space throughout the scan. The PV application GUI can generally be thought of as a collector. As a result, nothing prohibits the “sub” applications from similarly acting as a recursive collection of any number of other application GUIs.
The present invention improves workflow by increasing the intuitiveness of the application workflow, making the application more flexible, improving usability, decreasing the number of user interactions/steps, and incorporating fault tolerance. In one preferred embodiment, the PV application may be launched by “double clicking” an icon displayed on the console 16 , FIG. 1 . By launching the PV application, the user may create a new exam, edit an existing protocol, and/or enter patient information.
FIG. 2 is an illustration of a layout of a GUI in accordance with the present invention. GUI 100 is designed to dynamically adjust the layout and distribution of screen space throughout the scan. As illustrated, GUI 100 includes a generic control region 110 which occupies approximately 20% of the available screen space, whereas the remaining 80% of the screen space is reserved for control of a local or particular application 112 . In this embodiment, the region 110 will retain 20% of the total screen space and thereby limit the space available for region 112 . In this embodiment region 112 includes prescription area 114 and an operations area 116 .
However, in another embodiment as shown in FIG. 3 , GUI 100 ( a ) includes space 112 ( a ) which is distributed to include region 114 ( a ) but region 116 ( a ) is reserved for generic control operation. This occurs when the generic control application has the scanner resources and the control for the prescription application is simply being used to prescribe a scan session. In this embodiment, space associated with the Lx application 110 ( a ) and 116 ( a ) retains an additional 10 15% of the screen space. Therefore, the local application may utilize only 65 70% of the total screen space for conveying information.
FIGS. 2 and 3 illustrate various embodiments for allocating finite screen space among several medical imaging applications. Distributing the screen space in a position similar to that shown in FIGS. 2 and 3 facilitates ease of user interactions between applications. It should be noted that the present allocations described above are for illustrative purposes and are not intended to limit the scope of the invention.
Referring now to FIG. 4 , GUI 118 is shown having an initial setup window. GUI 118 is displayed when the PV application is first launched or, alternatively, when the user selects “Initial Setup” tab 119 ( a ) of modularizing tab array 119 . This view presents the user with an “Initial Setup” window 120 . Window 120 allows the user to perform the initial setup for the PV application. The user may establish settings such as acquisition settings 121 . Included in the acquisition settings 121 are coil 122 , number of stations 124 , and triggering mode 126 . Corresponding to coil 122 is a drop-down menu 128 that allows a user to select a coil such as a PV array. The user may input the number of stations in field box 130 and select the triggering mode 126 by choosing fluro triggered radial button 132 or timing bolus radial button 134 . If the user inputs a number stations greater than three, GUI 118 automatically updates to add additional modularizing tabs to array 119 .
Array 119 not only includes “Modularizing” tab 119 ( a ) corresponding to initial setup, but also includes a “Localizers” tab 119 ( b ), a “Station One” tab 119 ( c ), a “Station Two” tab 119 ( d ), a “Station Three” tab 119 ( e ), a “Summary” tab 119 ( f ), a “2D Fluro” tab 119 ( g ), and a “RunOff” tab 119 ( h ). Modularizing tab array 119 is vertically arranged along a left side of window 120 . The tabs 119 ( a )–( h ) correspond to each prescription step of an medical imaging scan session. The nomenclature provided for each tab is for illustrative purposes as differing medical imaging applications would utilize different tab names. The tabs are arranged vertically and, in a preferred embodiment, in order of execution. That is, tabs 119 ( a )–( h ) are logically arranged to guide a user through prescription of the medical imaging scanning session. When a particular tab is selected by a user, the tab is highlighted in a known manner to indicate selection of the particular tab. As shown in FIG. 4 , the appearance of GUI 118 is representative of that which appears upon user selection of “Initial Setup” tab 119 ( a ).
GUI 118 further facilitates user selection of image processing settings 136 such as identifying the proper auto subtraction processing 138 . In a preferred embodiment, the user may select one of arterial-mask 140 , venous-mask 142 , or venous-arterial 144 . The user may also indicate whether to create projection images by selecting check box 146 or create a collapsed image by selecting check box 148 . GUI 118 further includes a “Notes” button 150 that once selected by a user will cause a GUI or window to appear for entering of notes related to the instant medical imaging scanning session or protocol. A “Patient” button 152 is also provided that upon activation by a user will display information relating to the patient. A “Landmark” button 154 as well as an “Advanced Settings” button 156 are also provided and will be discussed shortly. Selection of “Landmark” button 154 causes another window (not shown) to appear which is configured to facilitate proper positioning of the scan subject. If the user has any questions or needs assistance relating to the prescription steps, the user may select “Help” button 158 to display various topics to assist the user with prescribing the imaging scan. “Scan Assistant” button 155 will be discussed with reference to FIGS. 17–21 .
As indicated previously, GUI 118 includes a prescription region 114 and generic control regions 110 , 116 . Region 116 includes an “Auto Pre-Scan” tab 160 , a “Manual Pre-Scan” tab 162 , a “Prep Scan” tab 164 , and a “Scan” tab 166 . User selection of these tabs 160 – 166 varies depending upon the particular application. Region 116 also includes status identifiers 168 that display the current scan time, completion status, and activation status.
Region 110 includes an Rx manager interface 170 that displays various information regarding the particular prescription. The Rx manager 170 includes a “View/Edit” tab 172 , a “Prepare To Scan” tab 174 , a “Save Rx As Protocol” tab 176 , an “Auto Scan” tab 178 , and an “Auto Step” tab 180 . Tabs 172 – 180 will display upon user selection thereof a corresponding window to facilitate user completion of the selected task or activity. A number of additionally status indicators and tabs are also provided in region 110 to provide information to the user as to the status of the scan session.
In a preferred embodiment, the user will make changes to the PV application settings when defining a new protocol. That is, a user may make selections in window 120 of GUI 118 and throughout other portions of the application, such as an “Advanced Settings” window (to be discussed shortly), and then save the settings as a new protocol. As a result, all subsequent executions of this PV application could utilize the created protocol and the user would typically only review the settings in the “Initial Setup” page and then click the next tab, the “Localizers” tab 119 ( b ), to begin the acquisition of data. When the user has entered all of the data for a particular tab, a check 181 will appear as a label to indicate that the necessary steps have been achieved.
Still referring to FIG. 4 , there are three stations for this application as indicated in the “Number of Stations” text field 130 . This is important because the number of stations determines the number of corresponding steps/tabs 119 for this application. Specifically, there is one tab per station for the acquisition of the 3D volume mask images and there is one localizer image set acquired per station. For example, if there were only two stations defined there would be one fewer tab (i.e. “Station 3” tab 119 ( e ) would not be necessary), only two localizers listed under the “Localizers” tab 119 ( b ), and only two stations for arterial and venous images. If the user entered six stations on the “Initial Setup” page 118 , the number of tabs 119 would update to add three more (i.e. “Station 4”, Station 5”, and “Station 6”), there would be six localizers under the “Localizers” tab 119 ( b ), and six stations for arterial and venous images.
The “Arterial-Mask” option 140 specifies that after acquisition of the arterial run images a set of subtracted images should be automatically generated using the masks. It should be noted that the auto-subtraction option 138 should be an improvement over existing systems as it automates and simplifies this application.
Workflow within this application works in the following way. A user navigates an application through a series of steps as conveyed by the tabs 119 on the left side of the screen 114 . There is a one-to-one relationship between the number of tabs 119 and the number of steps in the PV application. Therefore, in this embodiment, the PV application has eight steps corresponding to the number of tabs 119 . Preferably, the user moves through these tabs 119 from top to bottom. This is expected to be the preferred manner of completing this application, however, the user may complete the steps in any order. As all the tasks with each tab 119 are completed (i.e. the “Localizer” tab 119 ( b ) is only considered complete when the task of acquiring the localizers is completed) each tab 119 displays a checkmark icon 181 . This icon will indicate to the user that the step has been successfully completed. If a step has not been completed, partially or not at all, the tab will not have a check. Also, all seven steps prior to the “RunOff” step (i.e. the last step) must have been successfully completed in order to acquire the arterial and venous runs. That is, the PV application requires that all steps prior to the final step of arterial and venous acquisition be performed. The user will be notified of this requirement, if they try to acquire the “runs” without completing all prior steps, via the “Scan” button 166 being disabled and a message being displayed in the “Application Message” area 116 .
Referring now to FIG. 5 , a representation of GUI 118 upon user selection of “Localizers” tab 119 ( b ) is shown. Window 184 appears within GUI 118 and allows the user to review and/or change the scan parameters for each of the station localizers (as defined in the “Initial Setup” mentioned earlier). FIG. 5 is an illustration of how the user may multi-task effectively by “prescribing ahead” a local application while the system is busy scanning another generic series. The user may view “Patient Information” by clicking button 152 at the top of the screen in the “Global Information Access” area that contains the name and ID of the patient. A pop-up dialog will then be displayed on top of the PV application GUI 118 similar to that shown in FIG. 6 (which will be described below).
Window 184 allows the user to review and/or change the scan parameters for each station. The user may adjust the FOV 186 , slice thickness 188 , slices per frame 190 , and slice spacing 192 for each station. The user may also review and/or edit scan parameters relating to the center of the FOV 194 .
Once the user inspects and verifies the scan parameters presented, the user may select “Prepare to Scan” button 198 to initiate a resource switch to transfer the scanning resources and download. The user can then select “Scan” to initiate a scan for the localizer application and perform any necessary Prescan operations and then scan the localizers. The resource switch is a very important difference between the present system and other known systems. In the present invention, one must consider the consequences of the first selection of a scanning operation. This will cause a scanning resource switch, whether it is the first selection of a scan operation in the localizer application when the scanner is “owned” by the global application, or vice versa. Therefore, when a user selects scan, the first thing that occurs is a resource switch.
A “Humanoid” 196 is displayed in a right portion of window 184 . When the “Scan” button 198 is selected, all three localizers are automatically scanned and images are displayed in the “Humanoid”. This is an important step in improving the user workflow by automating redundant steps and streamlining how the user moves through this system. In a preferred embodiment, one cannot scan localizers in any other fashion. If there are more or less stations defined, as part of the initial setup, then there will be fewer or more localizers to be acquired. In either case, the localizer acquisition will be done automatically.
After selecting “Scan” button 198 , the GUI 118 will set forth the progress being made towards completion of the resource switch and scan in one of three ways.
First, the “Humanoid” 196 displayed to the immediate right of the localizer scan parameters window 184 will display localizers from each station as they are being acquired. That is, when the first localizer image from the first station (most superior in this case) is acquired the middle sagittal image 200 will be displayed in the top viewer of the “Humanoid” 196 . Each subsequent image 202 , 204 acquired for that station is also displayed. The “Humanoid” 196 provides the capability for the user to scroll through the images 200 – 204 . However, in one embodiment, the images displayed will only be sagittal images. As the system finishes acquiring the localizer from one station and then begins acquisition of a localizer at another station, the “Humanoid” 196 updates as necessary until the scanning completes.
The second way in which the user is made aware that the global application system is scanning is via progress bars 206 and a timer 208 , both of which indicate the progress towards the completion of the resource switch and localizer acquisition. Another bar (not shown) shows progress towards the completion of the resource switch on the scanner. Bar 206 indicates the percentage of the task completed based on images acquired versus total images. The “resource switch” progress bar will be displayed first and will be replaced by the “image acquisition” progress bar immediately after it completes. Timer 208 shows the count down of time for the image acquisitions. Timer 208 will be displayed when the “Scan” button 196 is selected, but will not begin counting down until the scanner actually begins the scan.
The final way in which the user is made aware that the global application system is scanning is via the desktop icon displaying the word “Scanning” 210 , the scan operation buttons being disabled, and, in most experiments, the user can hear the scanner as it is scanning.
Referring now to FIG. 6 , “Patient Information” window 212 appears upon user selection of patient tab 152 , FIG. 4 . Window 212 allows the user to view an accession number 214 , a patient ID 216 , name 218 , birth date 220 , sex 222 , weight 224 , age 226 , radiologist 228 , operator 230 , reference 232 , status 234 , exam description 236 , and history 238 . A “close” button 240 is also provided to allow the user to close window 212 .
Referring to FIG. 7 , once the user has acquired the localizers for the three specified stations, the user may select the next step, “Station 1” tab 119 ( c ), in order to display window 242 to prescribe and acquire the 3D mask images for the first station. The user may also proceed to the next step before acquisition of images. In this embodiment, the user cannot perform any further interactions associated with this step as the required localizer images have not been acquired. Alternatively, the user may select scan and move to the next step while the image acquisitions are occurring. In this embodiment, the user can begin the next step once the first localizer is acquired. Window 242 contains the same “Humanoid” 196 in the same location as in FIG. 5 . However, instead of the localizer imaging parameters for each localizer being presented, there is a 3-pane GRx tool 244 . Directly above the GRx tool 244 is a toggle button 246 that allows the user to move between viewing the acquired 3D mask images 248 – 252 and interacting with the 3-plane GRx tool 244 . Below the GRx tool 244 is the “Prep Scan” combination button 199 and the “Scan” button 198 as shown in FIG. 5 . These two buttons will not become active until after the user places the prescription on the image and no other application is scanning.
Once the 3D volume has been placed on the localizer images the user may interact with the 3D volume by dragging and rotating the 3D volume. Also, the user may use the tools located in GRx 244 .
Referring to FIG. 8 , most medical imaging applications employ policies for its scan and application parameters that prevent the user from entering invalid prescriptions. One tool that enforces these policies is referred to as “Scan Assistant” window 254 . In the PV application, the policy will be to “popup” a dialog 254 whenever a user enters parameters that are invalid. This dialog 254 will indicate to the user the error and force selection of another valid value. The user may choose between a default value 256 the system chooses, which is the next closest value to the invalid entry, or may enter another valid value 258. This tool 254 will prevent the medical imaging application from being in an invalid state. User may accept the changes by selecting “accept” tab 260 or cancel the change by selecting tab 262 . An alternate “Scan Assistant” tool will be described with respect to FIGS. 17–21 .
Referring again to FIG. 7 , to acquire the 3D mask images for this station, the user would select “Scan” button 198 . As described earlier, the “image acquisition” progress bar 206 and timer 208 are displayed while acquiring the images. Also, once the “Scan” button 198 is selected, the area of the screen occupied by the GRx tool 244 is replaced with an image viewer, FIG. 9 . Referring now to FIG. 9 , the image viewer 263 associated with “Station 1” button 119 ( c ) is displayed can be used to scroll through the acquired images as well as performing basic image operations such as window level and pan/zoom. In addition, the “Humanoid” 196 displays the 3D volume that was prescribed on the associated localizer and a “GRx/Viewer” toggle button 246 becomes active.
The “Humanoid” 196 also enables the viewer to display the localizer images selected to gain focus and also allows for the images in these viewers to be scrolled, pan/zoomed, and window leveled. The “Humanoid” 196 enables viewers to be selected which causes the PV application to switch to the associated prescription. For example, if the user “double-clicks” the third viewer in the “Humanoid” (i.e. station 3), the window associated with “Station 3” tab 199 ( e ) will become selected and the user can move forward with this step. Further, “Humanoid” 196 displays information such as the iso-center, station number, station acquisition time, and the time for table motion. Because there are three stations defined there are three 3D masks to be prescribed and acquired.
Referring now to FIG. 10 , after all mask image sets for each station have been acquired, the user may proceed to the “Summary” tab 119 ( f ). The purpose of “Summary” window 264 is to present the user with the option of reviewing the acquisition order, time to acquire the arterial and venous images, and to “skip” acquisition of any arterial or venous phase or to change number of phases. All of this is accomplished via the information panel 265 displayed to the left of the “Humanoid” 196 .
Window 264 clearly illustrates to the user everything that is scheduled to occur during the acquisition of the arterial and venous images. Things illustrated include:
Two columns indicating the arterial and venous acquisitions through the use of colored labels (i.e. red for arterial, blue for venous).
Colored labels contain the scan time for each series.
Check boxes next to the boxes allow the user to select or skip the acquisition. Therefore, in order to skip any step, the user only has to uncheck the check box associated with the particular acquisition.
Panel clearly shows the start of the acquisition as well as the total time listed for the acquisition. This number will dynamically update based on order selected and what is and is not being acquired.
In addition to the panel 265 , there are also two buttons 266 , 268 that the user can choose from in order to define the order of arterial and venous acquisition. One selection, “Venous Up” 266 acquires the arterial images superior to inferior and then the venous images inferior to superior thus reducing table movement. The second option is “Venous Down” 268 which acquires both the arterial and venous images superior to inferior. In one embodiment, “Venous Down” 268 is selected by default.
In addition to all that can take place during the “Summary” step, the present invention allows the user to re-acquire the 3D mask images for a particular station. Since the user may change the prescription for the 3D masks for station two and then re-acquire the images, the user need follow the same steps mentioned above when they first prescribed and acquired the 3D masks for station two. That is, “Station 2” tab 119 ( d ) is selected and the GRx tool is used to fix the prescription. The user then presses the “Scan” button. Reacquisition of mask images for station 2 does not affect the previously acquired data for the other stations. Once this is completed, the user selects the “Summary” tab once again to again review a summary of the data acquisition.
Referring to FIG. 11 , the present invention allows for prescribing of a fluoroscopy by selecting modularizing tab 119 ( g ) from GUI 118 . Upon selection of tab 119 ( g ), window 270 is displayed. Window 270 includes a GRx tool 272 for 2D prescription that enables the user to input various fluoroscopy parameters such as FOV 274 , slice thickness 276 , and number of slices per slab 278 . “Humanoid” 196 remains displayed in a right portion of the screen as well as localizer images 248 – 252 .
After prescribing the Fluoro acquisition, the user may then select “Runoff” tab 119 ( h ) to complete the final step in the imaging application.
Referring to FIG. 12 , window 280 appears when tab 119 ( h ) is selected. From window 280 , the user can acquire arterial and venous images in one of two ways. First, the user may use a real-time fluoroscopy technique to acquire the images. To acquire the images the user will begin by pressing the “Start Flour” button 282 , which will cause the viewer on this page to present the user with a real-time image 284 of the location that was prescribed and the “Start Fluoro” button will change its label to read “Pause Fluoro”. At this point the user could do one, none or both of the following:
A.Select the “ROI” button 286 and draw a Region of Interest (ROI) 288 over the area of interest on the image in the viewer 284 . This step is not required as the user could also visually detect bolus arrival. In this particular case, an ROI is used and as soon as it is placed on the image, the 290 in the top of window 280 updates with pixel intensity information.
B.Enter a time manually into the “Acquisition delay” text field 292 . This can only be done if the “Auto Trigger” 294 is selected. In this case, the user leaves text field 292 at zero which tells the system that the user must manually press the “Go 3D” or “Scan” button 296 to initiate a scan.
After implementing the Fluoroscopy, the user may start the injector by pressing the “Start injector” button 298 which will essentially begin the injection of the contrast agent. If the “Acquisition Delay” 292 had a value greater than zero, the viewer would start a timer and would auto-scan when it reaches the same value displayed in the “Acquisition Delay” text field 292 if “Auto Trigger” 294 was selected. The user may watch the image 284 in the viewer as well as the graph 290 in order to detect the arrival of the contrast. Once the contrast is detected, it is time to begin the scan. The user may give any necessary instructions to the patient (i.e. hold breath) and press the “Scan” button 296 , which will cause the sequence of arterial and venous image acquisitions to occur as prescribed in the “Summary” step. As these images are being acquired, they will be automatically displayed in the viewer. The user may scroll, pan/zoom, and window level these images.
A second way in which the user may acquire arterial and venous images is through the use of a timing bolus. To do this, the user must first prescribe the location for the fluoro image. The user may then start the fluoro acquisition by pressing the “Start Fluoro” button 282 . As the fluoro acquisition is occurring in real-time, the user may prepare themselves and the patient and then press the “Timing Bolus” button 300 . This will cause a few things to occur. First, button 300 will change to read “Mark Time” and still be active. Second, the image will display a timer 302 that is incrementing in seconds from the time the “Timing Bolus” button 300 is pressed and will not stop until the “Mark Time” button 300 is pressed. The final change from pressing the “Timing Bolus” button 300 is that the injector will inject a small amount of bolus into the patient, which the user will use to time the arrival of contrast into the fluoro image.
After the “Timing Bolus” button 300 is pressed, the user will watch the image 284 , and possibly the graph 290 , for the contrast to arrive. When the contrast is detected, the user presses the “Mark Time” button 300 . This action will cause timer 302 on the image to stop incrementing. Further, a “Time to Start” text field (not shown) will become active with the same value as the timer on the image. Next, the user may decide to change the value of the “Time to Start” text field by simply highlighting the field and entering in a new value, or leave it as is. (Note: Throughout this process, the fluoro acquisition continues to occur.) Now the user may acquire the arterial and venous run images.
When “Start Injector” button 298 is pressed, the full amount of contrast agent is injected into the patient and the value in the text field and the timer on the image will begin counting down therefore functioning as a visual queue/reminder to the user. If the auto trigger 294 is selected, the value in the text field and on the image reaches zero and scanner automatically begins acquiring the arterial and venous images. The user may manually press the “Go 3D” button 296 before the timer in the viewer reaches the value displayed in the “Time to Start” text field, but not after. If the auto trigger is not selected, the value in the text field and on the image only serves as a “guide” to the user that they should manually select the “Go 3D” button 296 when it reaches a value of zero. However, when the value does equal the “Time to Start” text field, nothing happens. Therefore, it is up to the user in this case to initiate the scan. They may do it before, after, or when the times equal. When the scan is initiated, a scanning timing bar 304 is displayed as well as a scan time timer 306 .
After the user has completed the acquisition of the arterial and venous images the user may save this particular instance of the PV application as a protocol that may be implemented at a later date without reentering each parameter. This allows for buildup of a protocol database that may be accessed in the future. To save the protocol, the user selects the “Save Rx as Protocol” button 176 inside the Rx Manager 170 on left side of the GUI.
Next and referring to FIG. 13 , the user may enter the identifying name for this protocol in text field 308 of the “Save Protocol Rx” dialog 310 that pops up and select the “Accept” button 312 . The user may also identify a protocol category using drill down menu 314 . To cancel “saving” of the protocol the user may select button 315 .
After this application is saved as a protocol, the user may want to close the exam as all series have been scanned. In order to end the exam, the user selects the “End Exam” button 171 on the left side of GUI 118 . This will cause the current contents of the scan window to be closed.
Referring again to FIG. 4 , the present invention allows for viewing and/or editing a screen series by selecting the “View Edit” button 172 , or by double clicking a desired series 179 . Either of these actions will cause the currently displayed window (immediately to the right of the Rx Manager) to be hidden, and the window associated with the selected series to be shown.
Referring to FIG. 14 , the present invention includes an “Advanced Settings” window 316 which allows the user access to all parameters, features, and tools associated with a particular application for viewing and/or editing. For example, window 316 allows the user to access parameters associated with image subtraction 318 , image projections 320 , as well as all scan and application parameters 322 that are not presented to the user throughout the steps of the application. The user may also view/edit advanced settings regarding patient information 324 .
Additionally, when the user launches the “Advanced Settings” window, the presentation within the dialog window will contain the parameters and advanced settings for the currently selected step in the application. This will be referred to as “context sensitive” behavior. For example, if the user has the “Initial Setup” window selected when the “Advanced Settings” button is clicked, the window that displays will be set to the parameters and advanced settings for the initial setup. Also, this dialog will contain the parameters and advanced settings for all components of the application, which can be reached via the scroll bar on the right-hand side of the dialog window. Note that the parameters and advanced settings are organized and listed in the dialog window in the same order that they appear in the application (i.e. “Initial Setup”, “Localizers”, . . . , “RunOff”). Once the user completes viewing/editing, window 316 may be closed by selecting button 326 .
Referring to FIG. 15 , a “Help” window 328 appears upon selection of “Help” button 158 , FIG. 4 . A number of help topics 330 may be listed to help the user clarify any issue. The help topics 330 may be application specific or specific to the activities of a particular tab 119 ( a–h ).
Much like the “Advanced Settings” window, FIG. 13 , the “Help” dialog is context sensitive. So, in this case when the dialog comes up the first choices presented to the user should relate directly to the currently selected step. Therefore, if the “Initial Setup” step was selected, the options in the “Help” window 328 should include projection and collapse images amongst other topics. Also, window 328 will allow the searching of all topics contained in the help system. The purpose of the help system, will be to answer user questions regarding how to complete an application, medical imaging physics questions, and serve as a place holder for user notes about a particular topic or application. The user may select close button 332 to close window 328 .
Referring to FIG. 16 , a protocol window 334 may be viewed which displays the contents that are not “context sensitive”. That is, the protocol information window 334 will always contain the same options for each application. All that will change between instances of the application are the values and settings for these options. Also, in one embodiment, these options can only be viewed in window 334 as they are not editable. After viewing the protocol information, the user may close window 334 by selecting close button 336 .
As discussed above, the present invention includes an “Advanced Settings” window whose context is adaptive to display those parameters and settings associated with a particular tab. These settings allow access to all possible application parameters and features for users that have special needs. For example, the “Localizer” tab in the PV application only displays a few scan parameters for each station. These options have been determined to be the most important, but some users may want access to other options. If so, the user need only select the “Advanced Settings” button and a page will be presented with all available options and features of the specific imaging application. The information that will be displayed to the user when the “Advanced Settings” button is pressed will depend on the currently selected step in the application. Like the “Help” window, the “Advanced Settings” window will be context sensitive in that it will display the parameters and advanced settings for the particular step in the application that is selected when the “Advanced Settings” is pressed. However, the user can still access any of the other parameters and advanced settings available for other steps in the application. The Advanced Settings for each modularizing tab are set forth below:1.
Initial Setup:
Patient Height
Patient Position
Patient Entry
Magnitude Subtraction
Complex Subtraction
Collapse Projections
Projection Increment
19 projections @ 20 deg. Increments
38 projections @ 10 deg. Increments
User Specified
Axis of Rotation
2.Localizers:
FOV
Slice Thickness
Spacing
Frequency
Phase
NEX
Phase FOV
Auto Center Frequency
Autoshim
Contrast
Coverage; center of FOV (R/L, A/P, S/I)
Number of slices per plane
Scan controls (scan, prescan, manual prescan, auto prescan)
Different number of images per 3-plane
3.3D Rx:
Plane
Mode
TE
Flip Angle
Bandwidth
FOV
Slice Thickness
Locs per slab/no. of slices
Frequency
Phase
NEX
Phase FOV
Frequency direction
Auto center frequency
no. of slabs
It uses the following options:
Variable bandwidth
ZIP2
ZIP512
CV10→ Special (on/off)
CV12→ Elliptic Centric (on/off)
Referse elliptic centric
4.Summary:
None
5.Fluoro Rx:
Plane
Mode
TE/TI
Tr
Flip Angle
Bandwidth
FOV
Slice Thickness
Matrix Frequency
Matrix Phase/PFOV
NEX
Frequency Direction
Auto Center Frequency
As indicated previously, the present invention utilizes a “Humanoid” configured to function as a visual tool that allows the user to interact with and navigate the application, gather data about the exam, and view images. The “Humanoid” displays localizer images for each station and allows access to a station's GRx viewer by “double-clicking” on the corresponding image. Further, the images will display prescription overlap from one view image to the another. “Double-clicking” an image in the “Humanoid” will immediately take the user to the step corresponding to that station's GRx. For example, selecting the middle viewer on the “Humanoid” will cause the current window to change to the window that would appear as if the “Station 2” tab had been selected. The station label will change slightly when the user is prescribing that station to indicate to which is the active station. The scan times displayed on the “Humanoid” will be updated dynamically based on changes. A user can scroll through the selected images in a viewer. A user can window/level the selected images in a viewer. A user can select and view different localizer planes on the “Humanoid” as well.
The present invention allows for messages to be displayed to a user. The error messages may be separated into two categories: application level messages and system/safety messages. System and safety level messages may be displayed in the upper left hand side of the GUI 118 , FIG. 4 . There are a couple of ways in which application level messages will be presented to the user. First, text messages may be placed within the applications panel underneath the tabbed pane and above the “Scan Ops” area of the screen. Another way in which these messages may be presented is through pop-up displays to the user. In the former case, the messages will typically be informational. The messages in the latter case will be due to erroneous user input into scan parameter fields.
In a further embodiment, the present invention includes a series of graphical windows that for the purposes of this application will be collectively referred to as a “Scan Assistant”. In known systems, the mechanism for preventing erroneous input of scan parameters by a user is to present to the user change in scan parameter label colors indicates a specific scan parameter value is out of range and needs to be changed to a suggested value. While the user is shown a valid range of the value read scan parameter, these systems fail to provide any information to indicate that scan parameters are inter-related and can depend on one another. If the value of one scan parameter is changed, it most probably affects another parameter value but with these known systems the user is not made explicitly aware that such a change has occurred unless the change causes a value to go outside a valid min/max range of values.
During a typical prescription of a scan session, a user wants to accomplish a number of tasks, such as, reducing scan time, increasing resolution, increasing contrast, and increasing signal-to-noise ratio. Other common tasks the user may wish to accomplish during the scan prescription include increasing coverage (i.e. number of slices), entering values outside a current valid range, and providing guidance on scan parameter dependencies. Current systems are capable of assisting the user in accomplishing each of these tasks, but not easily. Further, the user must fully understand at a physics level the inter-dependencies between scan parameters and manually change these parameters in a way that accomplishes the intended result.
The present invention solves these drawbacks by demonstrating the relationship between scan parameters, notifying the user of scan parameter validity, as well as suggesting possible ways to achieve a pre-defined set of specific goals, such as reducing scan time, increasing resolution, increasing contrast, increasing signal-to-noise ration, and increasing coverage.
The present invention provides prescription guidance by notifying the user when the user changes a scan parameter value of those other scan parameters that have been automatically changed, are out of a valid range, and require the user to enter a new value. That is, if the user inputs a scan parameter value that causes another scan parameter value to be changed and the change to the other scan parameter is valid, the scan assistant will notify the user that the other scan parameter value is valid and has therefore been automatically changed. However, if the user changes a scan parameter value which causes another scan parameter to be out of the valid range, the scan assistant will notify the user that the other scan parameter is now out of a valid range and is therefore invalid. Further, if the user changes a scan parameter value, the scan assistant is also configured to notify and prompt the user to enter a new scan parameter value for another scan parameter value that is dependent upon the changed parameter value.
The present invention further provides prescription guidance by prioritizing all the scan parameters into three categories on a per scan session or experiment basis. The scan parameters are prioritized into a primary, secondary, and tertiary group. This ranking defines the relationship between parameters and provides guidance how their values may be affected based on user input. For example, change in the value of a primary parameter, such as FOV, may affect other primary parameters as well as secondary parameters, such as, resolution, and tertiary parameters, such as, timing. However, changing a secondary parameter value may affect other secondary parameters as well as tertiary parameters, but would not affect a primary parameter. Moreover, changing a tertiary parameter may only affect other tertiary parameter values. This ranking promotes the notion of driving the physics from the geometry to the timing, rather than from timing to geometry as is typically done in known systems. Because the scan assistant recognizes the parameter relationship, it may assist the user in achieving the desired timing by facilitating geometry trade-offs.
Referring to FIGS. 17–21 , the Scan Assistant facilitates prescribing a scan session with reduced scan time, increased resolution, increased contrast, increased signal-to-noise ratio, and increased coverage by presenting the user with these options in a series of graphical windows. The user need only select the specific task option and the Scan Assistant will then display a list of possible ways to achieve the intended result as well as displaying trade-offs associated with achieving the intended result at the expense of other limitations of the system. The displayed trade-offs or consequences may be dynamically determined based on user input or, alternatively, include a list of canned or common trade-offs associated with modifying the particular trade option.
Now referring to FIG. 17 , window 338 is displayed on GUI 118 when the user selects “Scan Assistant” button 155 followed by a selection of “Scan Time” tab 340 . “Scan Time” tab 340 is one of a number of tabs 342 that allows the user to complete a fixed set of tasks related to prescribing a scan session or scan experiment. The additional buttons include a “Resolution” tab 344 , a “Contrast” tab 346 , an “SNR” tab 348 , and a “Slices” tab 350 . As indicated previously, window 338 is displayed when tab 340 is selected. Window 338 displays a number of options that may be modified for the selected application that are associated with scan time. For example, the user may select reduce TR 352 , reduce NEX 354 , or select reduce phase-in-frequency matrix 356 to further modify scan time for the selected application. Each option further includes a checkbox 358 that the user may select to indicate to the system that an option is to be edited. The user may then input modified scan values in field 360 for each selected option. When the user inputs a scan parameter value for any option in field 360 , a number of the most common consequences associated with changing that parameter value appear in field 362 . This allows the user to determine, in real-time, the effects of changing a particular scan parameter value.
Window 338 further includes a number of scan parameter display fields to convey general scan parameter data to the user. These additional scan parameter values include time 364 , number of slices 366 , number of acquisitions 368 , SNR 370 , spatial resolution 372 , CNR 374 , DB/DT 376 , Peak SAR 378 , estimated SAR 380 , average SAR 382 , and FPS 384 . A message area 386 is also provided to be used to convey messages to the user. A “Saved Series” tab 388 may be used to save modified scan parameter values.
Referring to FIG. 18 , when the user selects “Resolution” tab 344 window 390 is displayed that allows the user to modify the scan parameter values associated with resolution. Similar to window 338 of FIG. 17 , window 390 includes a number of boxes 392 that may be selected to indicate to the system that a particular scan parameter is to be modified. In the embodiment shown in FIG. 18 , the options which may be modified for the selected application related to the resolution functions include increase phase in frequency matrix 394 , reduce slice thickness 396 , reduce slice spacing 398 , and reduce FOV (not shown). The user may input a new scan parameter value or modify an existing scan parameter for each option by entering data in fields 400 corresponding to each particular option. Inputting of a modified scan parameter value will again result in a number of consequences associated with modifying the scan parameter value to appear on window 390 in fields 402 .
Referring to FIG. 19 , selection of “Contrast” tab 346 will result in window 406 being displayed. Window 406 allows the user to modify options related to the contrast for the selected application. Boxes 408 are provided that may be “checked” to indicate that a particular option is to be modified. In this embodiment, the options include reduce flip angle 410 , increase TR 412 , and increase TE 414 . The user may input modified data for each selected option in a corresponding field 416 . When the user inputs the modified scan parameter value in field 416 , the system automatically determines and displays a number of consequences associated with modifying the scan parameter value in field 418 .
Now referring to FIG. 20 , window 420 is displayed when the user selects “SNR” tab 348 . Selection of “SNR” tab allows the user to modify options for the particular application related to signal-to-noise ratio. The user may indicate that a particular option is to be modified by marking box 422 corresponding to each available option. In this embodiment, the available options include increase NEX 424 , reduce phase and frequency matrix 426 , increase slice thickness 428 , and reduce bandwidth 430 . After selecting a particular option to be modified, the user may input modified scan parameter value for particular option in fields 432 which results in the system automatically determining and displaying in field 434 the consequences associated with modifying the SNR value to the value input by the user. The user may scroll window 420 using tabs 421 ( a ) and 421 ( b ).
Now referring to FIG. 21 , selection of “Slices” tab 350 results in window 436 being displayed to the user. Window 436 allows the user to modify options related to coverage for the selected application. The user may do so by first selecting box 438 corresponding to a particular option to be modified. In this embodiment, the modifiable options include increase TR 440 , reduce TE 442 , increase bandwidth 444 , and reduce frequency matrix 446 . After selecting an option to modify, the user may input modified scan parameter values in a corresponding field 448 for each selected option. The system will then automatically determine based on the hierarchical nature of the scan parameter values, as discussed previously, display the consequences 450 of modifying the scan parameter value as input by the user.
In another preferred embodiment, the system automatically detects modification of a parameter rather than relying on a user to first select a “check box” signaling to the system that an option is to be modified.
Once the user has modified each option desired, the user may save the modified parameters for the particular application by depressing “Save Series” tab 388 . It should be noted, that the user need not view each window to save the series. That is, the user may elect to modify the options associated with scan time and contrast by viewing only those windows associated with those tabs but may elect not to modify the remaining tasks associated with a particular application. The user need not display each of the other tabs to save the series.
The present invention has been described with particular reference to a PV application implemented with an MR imaging system. However, the teachings of the present invention related to logical guidance of workflow for acquiring imaging data on a single GUI may be applicable to other medical imaging systems such as, CT, PET, X-ray, and ultra-sound.
Therefore, in accordance with one embodiment of the present invention, a graphical user interface is provided for prescribing a medical imaging session, acquiring diagnostic images, and processing imaging data. The GUI comprises a plurality of modularizing selectors configured to facilitate workflow through a medical imaging application. A plurality of status indicators are also provided wherein each status indicator corresponds with a modularizing selector and configured to display at least one of selection of the modularizing selector and completion of tasks associated with the modularizing selector. The GUI further includes a messaging module configured to automatically display messages regarding the MR application.
In accordance with another embodiment of the present invention, a graphical workflow management tool is provided for prescribing a medical imaging scan. The tool includes a GUI configured to be visually displayed on a console of a medical imaging system. The tool further includes a plurality of prescription tabs aligned vertically on the GUI. A plurality of status indicators are also provided on the GUI wherein each indicator is configured to display a status of activities for a corresponding prescription step. The tool further includes a plurality of context-specific tabs aligned horizontally on the GUI.
In yet another embodiment of the present invention, an MR apparatus includes a computer programmed to receive a launch MR application command and launch the MR application in response thereto. The computer is further programmed to receive a number of application steps. The computer is further programmed to display a GUI on a console, the GUI having a number of tabs equal to the number of identified application steps. The computer is also programmed to initialize a localizer scan for at least one localizer application step and display status of the localizer scan on the GUI and receive a prescription command and acquire MR images in response to the received prescription command for an application step. The computer is also programmed to receive another prescription command and acquire MR images in response to the received prescription command for another application step. Alternatively, the computer may be programmed to conduct prescription workflow for a number of identified sub-applications.
In a further embodiment of the present invention, a method of acquiring diagnostic images is provided and includes receiving a launch application instruction and launching the application. The method further includes determining a number of stations based on a received user input, wherein each station includes a number of localizers. The method also includes acquiring imaging data and displaying the imaging data on a GUI, the GUI having a number of context-specific tabs and a number of modularizing tabs.
The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims. | The present invention is directed to a method and apparatus that streamlines the process of prescribing and acquiring medical imaging experiments and data processing applications. The present application provides a modular intuitive and guided workflow having a graphical user interface that may be tailored and made singular and unique for each individual application. The user interface implements a guided management tool that incorporates the general principle that user activity is more efficient when it begins in the upper left-hand portion of the screen and proceeds horizontally across the screen moving from left-to-right and top-to-bottom. The user interface incorporates a number of tabs wherein each tab corresponds to a major prescription step. The tabs are aligned vertically along the left side of the user interface and are used to modularize the application workflow. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to and the benefit of Korean Patent Application No. 10-2015-0095658 filed on Jul. 6, 2015, the entire contents of which is incorporated herein for all purposes by this reference.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The present invention relates to an engagement device of a wiper and a vehicle body. More particularly, the present invention relates to an engagement device of a wiper and a vehicle body that fixes a motor of the wiper to the vehicle body and applies electric power to the motor.
[0004] Description of Related Art
[0005] A wiper apparatus of a vehicle is a safety apparatus that secures a clear view for a driver when driver's vision is bad due to weather condition such as rain and snow or dust and stain on a windshield glass. The wiper apparatus is adapted to wipe raindrop, snow, dust and stain on the windshield glass using a wiper blade.
[0006] The wiper apparatus may be mounted at a rear window, a side mirror, a headlamp as well as the windshield of the vehicle. Particularly, a predetermined parking space for receiving a wiper blade is formed under a hood and the wiper blade is positioned in the parking space and is not able to be seen from the exterior in order to secure a beautiful exterior near a cowl according to recent vehicles.
[0007] One example of such wiper apparatus is disclosed in Korean Patent Laid-Open Publication No. 2010-0023583. The wiper apparatus includes a motor, a frame and a linkage.
[0008] Generally, the wiper apparatus is made as a module and the module is fixed to the vehicle body. According to a method of fixing the wiper apparatus to the vehicle body, a mounting portion of bracket shape is formed on the frame and is fixed to the vehicle body through engagement means such as a bolt, a nut and so on.
[0009] According to a conventional mounting portion, however, electric power is hard to be applied to the wiper apparatus. Therefore, a structure for fixing the wiper module to the vehicle body and applying electric power to the wiper module simultaneously has been researched.
[0010] The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
BRIEF SUMMARY
[0011] Various aspects of the present invention are directed to providing an engagement device of a wiper and a vehicle body having advantages of fixing a motor of a wiper to a vehicle body and applying electric power to the motor simultaneously.
[0012] An engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention may include: a motor for driving the wiper; a motor bracket fixed to the motor; a cowl bracket fixed to the vehicle body corresponding to the motor bracket; and a mounting portion forming a fixing structure between the motor bracket and the cowl bracket, wherein the mounting portion comprises a protrusion protruded from the motor bracket or the cowl bracket, and a socket, the protrusion being inserted into and fixed to.
[0013] A power connecting portion for supplying electric power to the motor may be formed at the protrusion or the socket. The power connecting portion may include: at least one terminal protruded from the protrusion or the socket; and at least one terminal insertion hole formed at the socket or the protrusion corresponding to the at least one terminal.
[0014] A plurality of terminals may be disposed apart from each other, and a plurality of terminal insertion holes may be formed corresponding to the plurality of terminals.
[0015] The protrusion may be press-fitted into and fixed to the socket.
[0016] An exterior circumferential groove may be formed on an exterior circumference of the protrusion, and an interior circumferential groove may be formed on an interior circumference of the socket corresponding to the exterior circumferential groove. The engagement device may further include a fixing ring disposed in an annular space formed by the interior circumferential groove and the exterior circumferential groove and preventing the protrusion and the socket form be disengaged from each other.
[0017] The cowl bracket may be fixed to a cowl panel defining a boundary between an engine compartment and a vehicle cabin.
[0018] The motor bracket may be fixed to a motor housing enclosing the motor.
[0019] The protrusion and the socket may be fixed to the motor bracket or the cowl bracket through fixing bolts.
[0020] The terminal and the terminal insertion hole may be made of electrically conductive material so as to be electrically connected to each other and may include an electric wire connected to the terminal or the terminal insertion hole.
[0021] The protrusion, the socket and the fixing ring may be made of metal material.
[0022] The mounting portion may include: a fixing loop fixed to the cowl bracket; a hook fixed to the motor bracket, rotatably disposed through a hinge, and hooked by the fixing loop; and a locking member rotatably disposed at the hook and prevent rotation of the hook such that the hook is disengaged from the fixing loop.
[0023] An engagement device of a wiper and a vehicle body according to another exemplary embodiment of the present invention may include: a motor for driving a wiper on a window glass; a motor bracket fixed to the motor; a cowl bracket corresponding to the motor bracket and fixed to a vehicle body; a protrusion protruded from the motor bracket or the cowl bracket; and a socket formed at the cowl bracket or the motor bracket so as to be inserted in the protrusion, wherein an exterior circumferential groove is formed on an exterior circumference of the protrusion, an interior circumferential groove corresponding to the exterior circumferential groove is formed on an interior circumference of the socket, and a fixing ring is disposed in an annular space formed by the interior circumferential groove and the exterior circumferential groove and prevents disengagement of the protrusion and the socket.
[0024] According to an exemplary embodiment of the present invention, a wiper unit is fixed to a vehicle body and electric power is applied to the wiper unit simultaneously in such a way that a protrusion is inserted into a socket.
[0025] In addition, assembling efficiency may be improved by means of simple assembling structure, assembling strength may be increased by means of insertion structure, and dispersion error of assembling may be reduced.
[0026] The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a front view of a wiper unit according to an exemplary embodiment of the present invention.
[0028] FIG. 2 is a partial cross-sectional view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0029] FIG. 3 is a partial perspective view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0030] FIG. 4 is a partial perspective view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0031] FIG. 5 is a partial cross-sectional view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0032] FIG. 6 is a partial perspective view illustrating an engagement device related to an exemplary embodiment of the present invention.
[0033] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
[0034] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
[0035] Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
[0036] Exemplary embodiments of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
[0037] FIG. 1 is a front view of a wiper unit according to an exemplary embodiment of the present invention.
[0038] Referring to FIG. 1 , a wiper unit includes a motor 100 , a mounting portion 150 , a gear box 102 , a rotating arm 120 , a delivery link 130 and a rotating shaft 140 .
[0039] The motor 100 generates torque by supplied electric power, the gear box 102 increases the torque of the motor 100 through gear ratio, and the rotating arm 120 transmits the increased torque. The motor 100 is enclosed by a motor housing.
[0040] The delivery link 130 is connected to an end portion of the rotating arm 120 and the rotating arm 120 rotates the rotating shaft 140 through the the delivery link 130 . In addition, an end portion of a wiper is fixed to the rotating shaft 140 and the wiper wipes a surface of a window glass and removes moisture or dust from the window glass by rotation of the rotating shaft 140 .
[0041] The mounting portion 150 is fixed to and is disposed at a side of the motor 100 . The mounting portion 150 is fixed to a cowl panel of a vehicle body defining a boundary between an engine compartment of a vehicle and a vehicle cabin. In addition, the mounting portion 150 may be fixed to the gear box 102 or a motor bracket 105 (see FIG. 2 ) fixed to the motor 100 (or the motor housing).
[0042] Since the cowl panel of the vehicle body and operation of the wiper according to the exemplary embodiments of the present invention are well known to a person of an ordinary skill in the art, detailed description thereof will be omitted.
[0043] FIG. 2 is a partial cross-sectional view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0044] Referring to FIG. 2 , an engagement device includes a first electric wire 320 , a cowl bracket 200 , a fixing bolt 250 , a motor bracket 105 , a second electric wire 325 and a mounting portion 150 , and the mounting portion 150 includes a protrusion 305 and a socket 300 .
[0045] The cowl bracket 200 is fixed to the cowl panel of the vehicle body and the motor bracket 105 is fixed to an exterior surface of the motor 100 corresponding to the cowl bracket 200 .
[0046] The protrusion 305 is fixed to the cowl bracket 200 by the fixing bolt 250 and the socket 300 is fixed to the motor bracket 105 by the fixing bolt 250 .
[0047] The protrusion 305 is press-fitted and fixed to the socket 300 , and the first electric wire 320 and the second electric wire 325 supplies electric power from a battery to the motor 100 through a connection structure of the protrusion 305 and the socket 300 .
[0048] FIG. 3 is a partial perspective view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0049] Referring to FIG. 3 , a terminal 350 of metal material is protruded from a front surface of the protrusion 305 and is disposed to receive current from the first electric wire 320 .
[0050] In addition, at least two terminals 350 may be disposed apart from each other on the front surface of the protrusion 305 .
[0051] FIG. 4 is a partial perspective view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0052] Referring to FIG. 4 , a protrusion recess 400 is formed at the socket 300 and a terminal insertion hole 410 into which the terminal 350 is inserted is formed on an interior surface of the protrusion recess 400 . The terminal insertion hole 410 is disposed to supply current to the second electric wire 325 .
[0053] In addition, at least two terminal insertion holes 410 corresponding to the terminals 350 may be disposed apart from each other.
[0054] FIG. 5 is a partial cross-sectional view of an engagement device of a wiper and a vehicle body according to an exemplary embodiment of the present invention.
[0055] Referring to FIG. 5 , a rear end portion of the protrusion 305 is inserted into and fixed to the cowl bracket 200 , and a rear end portion of the socket 300 is inserted into and fixed to the motor bracket 105 .
[0056] In addition, the protrusion recess 400 is formed at the socket 300 corresponding to the protrusion 305 , and the protrusion 305 is inserted into the protrusion recess 400 so as to be fixed thereto.
[0057] An exterior circumferential groove 520 is formed at an exterior circumference of the protrusion 305 , and an interior circumferential groove 515 corresponding to the exterior circumferential groove 520 is formed at an interior circumference of the socket 300 .
[0058] The interior circumferential groove 515 and the exterior circumferential groove 520 form an annular space, and a fixing ring 510 is disposed in the interior circumferential groove 515 and the exterior circumferential groove 520 .
[0059] The fixing ring 510 is disposed simultaneously in the interior circumferential groove 515 and the exterior circumferential groove 520 and prevents disengagement of the protrusion from the socket 300 .
[0060] In the exemplary embodiment of the present invention, the socket 300 , the protrusion 305 and the fixing ring 510 may be made of metal material, and the protrusion 305 is press-fitted and fixed to the socket 300 .
[0061] FIG. 6 is a partial perspective view illustrating an engagement device related to an exemplary embodiment of the present invention.
[0062] Referring to FIG. 6 , a hook 600 , a fixing loop 615 and a locking member 610 are disposed between the motor bracket 105 and the cowl bracket 200 .
[0063] The fixing loop 615 is fixed to the cowl bracket 200 and the hook 600 is rotatably disposed at the motor bracket 105 through a hinge 605 .
[0064] If the hook 600 rotates about the hinge 605 , the hook 600 is hooked to the fixing loop 615 so as to be fixed thereto.
[0065] In addition, the locking member 610 is rotatably disposed at the hook 600 . In a state that the hook 600 is fixed to the fixing loop 615 , the locking member 610 is locked up so as to prevent disengagement of the hook 600 from the fixing loop 615 .
[0066] Operation of the hook 600 , the fixing loop 615 and the locking member 610 shown in FIG. 6 is well known to a person of an ordinary skill in the art, detailed description thereof will be omitted.
[0067] It is exemplified in FIG. 1 that one mounting portion 150 is disposed at the motor bracket 105 fixed to the motor 100 , but additional mounting portions 150 may be disposed at the motor bracket 105 .
[0068] In addition, it is exemplified in FIG. 2 that the protrusion 305 is fixed to the cowl bracket 200 and the socket 300 is fixed to the motor bracket 105 , but the protrusion 305 may be fixed to the motor bracket 105 and the socket 300 may be fixed to the cowl bracket 200 .
[0069] For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
[0070] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. | An engagement device of a wiper and a vehicle body may include a motor for driving the wiper; a motor bracket fixed to the motor; a cowl bracket fixed to the vehicle body corresponding to the motor bracket, and a mounting portion forming a fixing structure between the motor bracket and the cowl bracket, wherein the mounting portion comprises a protrusion protruded from the motor bracket or the cowl bracket, and a socket, the protrusion being inserted into and fixed to. | 7 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to apparatus for opening bales of textile fibers. It is concerned particularly with bale openers adapted to accommodate the blows which are inflicted by ropes and other foreign objects thrown from the bales during operation of the apparatus.
The type of bale opener with which the present invention is concerned includes at least one opening roll which is rotatably journalled within a housing. The housing is open at its side facing the fiber bales and the direction of rotation of the roll is reversible depending on the prevailing direction of travelling movement of the housing relative to the fiber bales. The roll and the housing walls are spaced apart to provide flow channels and suction is applied to draw air and fiber through the channels and to an outlet conveyor duct. There is a deflection member for the fiber flocks which extends longitudinally over the top of the roll. It deflects fiber flocks supplied on one side of the roll into the fiber flow passage and at least largely prevents leakage of air coming from the other side of the roll. It is desirable that this deflection element be able to deviate or shift under the action of blows (such as those caused by foreign particles) which act on it during bale opening.
An apparatus of this general kind is for example disclosed in European Patent Application Publication No. 130 369.
The articles which cause such blows are frequently ropes or other foreign articles which are present in the bales. Such blows can also arise through large quantities of torn out fiber flocks. The sensitivity of the apparatus against such blows, and above all the ability of the deflecting member to deflect rapidly in order to avoid damage to this member is restricted by the inertia of the deflecting member and the parts which move with the latter. In order to ensure a light manner of construction of the deflecting member, the pivot axis of the deflecting member must be so arranged in the known arrangement that the pressure difference acting on the pivot member does not lead to any deformation or excess loading of the deflecting member or of the positioning means therefor.
There are however certain restrictions with respect to the position of the axis of rotation of the deflecting member and also its construction. In further embodiments of the known apparatus the deflecting member is only used to deflect the fibers and a separate pivotally mounted flap bounds the conveyor path and bears eventual blows from foreign articles. This additional separate flap however represents a complication of the apparatus. While this complication may be acceptable in an arrangement with only one roll, one would prefer not to have these separate flaps, particularly in apparatus having two rolls disposed alongside one another.
SUMMARY OF THE INVENTION
Objects of the present invention are to provide apparatus of the initially named kind that permits the inertia of the deflecting member and of the parts movable therewith to be reduced without the penalty of a complicated arrangement, and to provide an apparatus of this kind which is well suited for installation in bale opening machines with two opening rolls arranged alongside one another.
In accordance with the invention, the deflecting member is formed as a pivotable flap which is pivotally secured at its side ends, via respective pivot axes, in the region of its longitudinal edge adjacent the roll to respective links for executing pivotal movements about an axis of rotation which extends parallel to the longitudinal edge. The two links ar pivotally journalled on the housing at their ends remote from the pivot axes; and at least one means acts on at least one of the pivot axes to change over the direction of the pivotal flap in accordance with the direction of rotation of the opening roll.
In this way a very compact deflection device is provided, and the different positions of the pivot axis of the pivotal flap for the deflection movement and the pivot axis of the link for the deviation movement make it possible to attain an excellent adaptation to the technical circumstances. Since the deviation movement of the pivotal flap and of the link arrangement takes place on the occurrence of blows about a pivot axis which is located in the region of one longitudinal edge of the pivot flap, the inertia of this arrangement is substantially reduced relative to the known arrangement in which a partly cylindrical deflecting member is pivotable about the cylinder axis.
In an apparatus for opening bales of textile fibers in which the roll is pivotally journalled on plates at the end faces of the housing, the apparatus of the invention is preferably characterized in that the pivot flap is located between the plates whereas the links are arranged outside of the plates.
In this arrangement, provision is made that the pivot axes extend through the respective plates and that the plates have arc-like slots for the pivot axes with the arc-like slots being of circular curvature and having a center of curvature which coincides with the pivot axis of the links.
In this way the links and also the means for deflecting the pivot flap can be arranged at the outersides of the plates so that they are readily accessible and are not subjected to any particular danger of contamination, since they lie outside of the fiber conveying region. It is only the pivot flap itself which is located between the plates.
In a particularly preferred embodiment, the means for changing over the pivot flap comprises an extendible and retractable unit which is pivotally connected at its one end on a lever which is pivotally fixedly mounted on the associated pivot axle and is likewise pivotally mounted to a link at a distance therefrom.
In this arrangement, provision is preferably made that the extendible and retractable unit is pivotally connected at its end remote from the lever to a further lever which is mounted on the associated link in the region of its pivot axle at the housing.
In this way the drive means for the deflection of the pivot flap, which is preferably constructed as an extensible and retractable piston and cylinder drive, or as an extensible and retractable spindle drive, can be so mounted that it participates in deviation movements of the link and of the pivot flap without a separate resilient mounting for the motor being necessary.
This however also has the advantage that the angular position selected during the change-over between the pivot flap and the link is also retained during the deviation movements. Thus the deviation movements executed by the pivot flap and by the links can be predetermined within close limits, which substantially simplifies the design and the computation of the inertia. Furthermore, the stresses which occur in the case of blows in the extendible and retractable unit provided for deflection of the flap are restricted, so that this unit does not need to be made excessively large in order to bear these stresses, and the inertia of the arrangement is not unnecessarily increased by an over-dimensioned drive unit.
The position of the links is, in accordance with the invention constant during the entire normal operation of the apparatus. It only changes during deviation movements as a consequence of blows. This constant position of the links can be realized in accordance with the invention in a particularly simple manner if one provides a spring system which acts on one or both links and biases these into the predetermined position. The spring system also serves to resiliently accommodate the forces which arise through blows. For small blows, which need not lead to interruption of operation, the spring system moves the links and the pivot flaps back into the desired initial positions after the foreign matter has passed.
In accordance with a particularly preferred embodiment, the spring system is so constructed that the pivotally journalled end of the biased link has an opening through which a boss passes. The boss determines the pivot axis for the link and elastomeric spring elements are arranged in this opening between the link and the boss.
By building the spring system into the region of the pivot axis of the link, the inertia of the entire arrangement is also kept small. Although the above mentioned spring system using elastomeric springs is preferred, a spring system could also be realized in another manner. For example, the boss which determines the pivot axis of the link could be formed as a torsion spring or torsion bars.
Since the foreign articles which cause heavier blows must be removed from the machine, it is desirable to interrupt the operation of the machine, or at least to generate a warning signal, when such blows occur. This can take place in accordance with the invention through the provision of switching cams at the head of the link which swings in response to the blows. The switching cams activate appropriate electric switches to bring about the desired effects. One can construct the arrangement such that the switching cams are mounted on the link (or on parts movable with the latter) and cooperate with a counter element during a deflection of the link in response to a blow to initiate a switching process for generating a warning signal and/or for stopping the operation of the machine.
As initially mentioned, the apparatus of the invention is particularly well suited for bale opening machines with two opening rolls arranged alongside one another. A machine of this kind is preferably constructed such that it has two opening rolls arranged alongside one another in a common housing; that a partition wall is arranged between the two rolls with the partition wall extending upwardly and bounding, together with the housing, at least a part of the fiber passage; that one pivot flap is provided for each roll and that the two pivot flaps are deflectable in the same rotational sense corresponding to the prevailing direction of rotation of the rolls.
In a bale opening machine of this kind, the arrangement of the invention is such that, in one deflection position of the pivot flaps, the longitudinal edge of one of the flaps remote from its associated roll contacts the partition wall, while the corresponding edge of the other pivot flap contacts the wall of the fiber passage formed by the housing. In the other deflection position, the longitudinal edge of the first pivot flap remote from its associated roll contacts the wall of the fiber passage formed by the housing, while the corresponding edge of the other pivot flap contacts the partition wall.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be explained in further detail in connection with embodiments illustrated in the drawings, in which:
FIG. 1 is a schematic cross-section through an opening arm of a bale opening machine with two opening rolls;
FIG. 2 is a schematic illustration of the right-hand opening roll of FIG. 1 with the pivot flap in the position A and with additional particulars of the arrangement being shown;
FIG. 2A is a detail from FIG. 2;
FIG. 3 is the same arrangement as FIG. 2 but with the pivot flap in the position designated B in FIG. 1;
FIG. 4 is a representation which largely corresponds to FIG. 2, but which shows a somewhat modified embodiment;
FIG. 5 is the same arrangement as FIG. 4, but with the pivot flap in the position B of FIG. 1;
FIG. 6 is a perspective illustration of a further embodiment; and
FIG. 7 is a schematic view of an alternative suspension for the links of the embodiment of FIG. 2.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows first of all a cross-section through the opening arm 10 of a bale opening machine having two opening rolls 11 and 12 which are arranged parallel to one another in a housing 13 formed by the arm 10. At its two side ends the housing has so called shields (plates) of which only the rear plate 14 can be seen in FIG. 1.
The opening rolls 11 and 12 which carry toothlike members (not shown) in order to free the fiber flocks from the bales 15 lying beneath them are rotationally journalled in the shields 14. The rotational axes of the rolls 11 and 12 are designated by 16 and 17, respectively. The circles 18 and 19 show the circular paths of movement of the tips of the teeth when the opening rolls 11 and 12 move in the direction of rotation 21 which corresponds to an opening movement of the arm along a row of bales in the direction of the arrow 22.
The housing 13 is open at its lower side facing the row of bales 15 so that the teeth of the opening rolls 11 and 12 can extend through gaps between the customary grid bars 23 in the lower part of this circular movement in the direction of the arrow 21. The grid bars 23 or the grids formed hereby can be constructed in accordance with German patent application P 38 20 427.4 or in accordance with the German patent application P 38 27 517.1 or otherwise. As usual the teeth of the opening rolls execute a swash plate movement during their rotary movement about the respective axes of rotation 16 and 17.
A vertical partition wall 26 is located between the two opening rolls 11 and 12 and, in its upper region, forms two flock passages or conveyor shafts 29 with two wall parts 27, and 28 of the housing 13. These two conveyor shafts open into a flock conveying duct 31 which extends along the opening arm 10 and which is connected to a source of suction.
Above the opening roll 11 there is located a pivot flap 32 and a corresponding pivot flap 32 is also to be found above the opening roll 12.
In the position A shown with continuous lines, the upper longitudinal edge 33 of the left-hand pivot flap 32 is in contact with the partition wall 26. The lower longitudinal edge 34 of the left-hand pivot flap is located above the opening roll 11. In this manner the pivot flap 32 forms, together with the opposite wall part 28 of the housing, a conveying passage for the flocks which are removed from the bales 15 and separated out by the opening roll 11. These flocks first move in the direction of the arrow 35 and are then deflected into the direction of the arrow 36 and fed into the conveyor shaft 31. At the same time the pivot flap 32 blocks the flow of leakage air in the direction of the arrow 37 through the gap between the right-hand side of the opening roll 11 and the partition wall 26. This leakage air flow would otherwise arise because of the vacuum in the conveyor shaft 29 resulting from the connection of the conveyor duct 31 to a suction source. By blocking this leakage air flow, the illustrated arrangement causes the suction to act on the flocks to move them in the direction of the arrow 35 and to transport them through the shaft 29 and into the conveyor duct 31.
The upper longitudinal edge 33 of the right-hand pivot flap 32 in FIG. 1 contacts the wall 27 of the housing 13 and likewise blocks a leakage air flow in the direction of the arrow 37 between the right-hand side of the opening roll and the wall 27. The flocks removed by the roll 12 move between this right-hand pivot flap 32 and the partition wall 26 into the right-hand conveyor shaft 29.
It is shown in broken lines that both the left-hand pivot flap 32 and also the right-hand pivot flap 32 can be swung over in the direction of the arrows 38. They swing about respective pivot axes 39 which are located in the region of the lower longitudinal edges 34 of the respective pivot flaps. This pivotal movement is carried out until the upper longitudinal edge 33 of the pivot flap on the left-hand side of the partition wall 26 contacts the wall 28 of the housing and until the corresponding upper longitudinal edge 33 of the right-hand pivot flap contacts the partition wall 26. Such positions are indicated in both cases by the letter B.
FIG. 2 shows further particulars of the suspension of the right-hand pivot flap 32 of FIG. 1 at the time when this pivot flap is located in the position A. It will be understood that the drawing of FIG. 2 could also represent a drawing of a pivot flap in the position A in a bale opening machine which has only one opening roll 12.
From FIG. 2 one can see that a pivot axle in the form of the stub axle 41 is mounted on the pivot flap 32 in such a way that it is coaxial to the pivot axis 39, i.e., it extends in the lower region of the pivot flap parallel to its longitudinal edge 34. This stub axle 41 is pivotally mounted in one end of a vertically upright link 42, the other end of which terminates in an enlarged approximately square head 43 which is pivotally arranged about a pivot axis 44. A one-armed lever 45 is rotationally fixedly secured to the pivot axle 41 and an extendible and retractable device 46, such as a cylinder and piston unit, is pivotally connected to the free end of the one-armed lever 45 at 47. The end of the unit 46 remote from the lever 45 is pivotally connected at 48 to one plate of the arm 10 of the bale opening machine.
The link 42 can be pivotally connected to the plate of the arm 10 by spring means. As can be seen from FIG. 2 the enlarged end 43 of the link 42 has a circular opening 49 through which, as shown in FIG. 2A, a boss secured to the shield of the opening arm passes. As is evident from FIG. 2A four rubber blocks 50 are inserted between the square shaped boss 40 and the wall of the opening 49 and ensure that the link 42 is biased into the position illustrated in FIG. 2.
If now a foreign article, such as for example a length of rope, is released from the fiber bale and thrown by the movement of the opening roll against the lower edge 34 of the pivot flap 32 and the pivot flap can deflect through compression of the rubber blocks into the position illustrated in broken lines in FIG. 2.
As likewise evident from FIG. 2a two switching cams 51 and 52 are provided at the upper edge of the square head 43 of the link 42. During the deflection movement of the pivot flap 32 into the broken line position of FIG. 2 the switching cam 51 moves into the position 51' and there actuates a corresponding switch (not shown) which serves to generate a warning signal and/or to stop the operation.
The switching cams 51 and 52 do not need to be provide at the head of the link 42. Instead an initiator or an infrared light barrier can also be provided which is directed towards the lever 45. This initiator can serve two functions: first of all, a switching-off function in the end position on extension or retraction of the unit 46, and secondly, a monitoring function when a blow at the edge 34 causes the pivot flap 32 to deflect. In the latter case the operation can be interrupted and/or a warning signal can be triggered.
FIG. 3 shows the same arrangement as FIG. 2 with the exception that the spindle 53 of the spindle drive 46 is extended in order to bring the pivot flap 32 into the inclined position shown with continuous lines in which its upper longitudinal edge 33 contacts the partition wall 26, i.e., the pivot flap 32 is located in the position B. One sees that the link 42 retains its vertical position during this movement. In this position the opening arm moves in the arrow direction 54 while the opening roll 12 now operates in the counter clock-wise direction of arrow 56. If now a foreign article executes a blow on the lower edge 34 of the pivot flap 32, the latter deviates into the angular position shown in broken lines against the bias of the spring means of FIG. 2a. During this movement the switching cam 52 moves into the position shown at 52' and actuates a switch which in turn serves to stop the machine and/or to generate a warning signal.
FIG. 4 shows a representation of an embodiment which is similar to the embodiment of FIG. 2, but in which the lever 45 has a different angular position in comparison to the corresponding lever 45 of FIG. 2. The switching drive unit 46 of this embodiment is also not pivotally connected to the shield or housing of the opening arm but rather to the end of a further one-arm lever 61, the other end of which is secured to the enlarged head 43 of the link 42. In this way the retractable and extendible unit 46 fully participates in the deviation movement as is shown by the broken line illustration of the unit 46.
FIG. 5 then shows the arrangement of FIG. 4 after the pivot flap has been swung over into the inclined position B, in this case by retraction of the unit 46 in comparison to the extended position shown in FIG. 4.
It will be understood that a unit 46 of this kind can be provided at only one end of the pivot flap or at both ends of the pivot flap. This also applies for all other embodiments. It is also to be understood that the pivot flap on the left-hand side of the double arrangement of FIG. 1, together with the associated drive and link, may be constructed as in the arrangement at the right-hand side of FIG. 1.
FIG. 6 shows a perspective illustration of a modified embodiment in which the same parts have the same reference numerals as in the previous Figures and in which the plate 14 of the housing 13 of the opening arm 10 is also visible.
For the sake of illustration only the one end of the pivot flap is shown. One can see that the pivot axle 41 of the pivot flap is also pivotally arranged in one end of the link 42. In this embodiment, however, the end of the pivot axle 41 which projects through the link 42 carries a belt pulley 60 which is pivotally connected via a belt 62 with a deflection pulley 63. The deflection pulley 63 is pivotally journalled on a stub axle on the link 42. Above the pulley 63 there is located a further pulley 64 which engages with the outerside of the belt 62 or, as an alternative, is rotatably coupled with the pulley 63 via gear wheels (not shown). The further pulley 64 is driven to execute a restricted pivotal movement by a motor 65 and a connecting member 66. This restricted pivotal movement of the pulley 64 leads to a corresponding movement of the deflection pulley 63 and via the belt 62 to a corresponding pivotal movement of the pulley 60, and thus of the pivot flap, so that the latter can be changed over from the position A to the position B and vice versa. The motor 65 can in this case either be rigidly secured to the bearing shield 14, or, as known in the prior art, mounted by way of a resilient mounting. A resilient mounting of this kind is laid out such that the forces which are necessary to adjust a pivot flap between the positions A and B are not sufficient to cause a substantial extension or compression of the resilient spring system but permit a deviation movement of the pivotal flap as a result of a blow.
In the embodiment of FIG. 7, the link 42 is pivotally connected to the associated shield or housing member 14 via a ball clutch or coupling 71 as an alternative to the arrangement shown in FIG. 2A. The ball clutch comprises a ring 72 which is secured to the bearing shield and which has, at its end face adjacent the link 42 recesses 73, for example in the form of bores which accommodate balls 74. At the side remote from the ring 72 the balls fit into corresponding recesses 75 in the head of the link 42. A boss 76 projects through the ring 72 and also through the head of the link and carries a compression spring 79, here in the form of plate springs, which press the link 42 against the ring 72. The spring force is moreover born at an abutment 77 which is adjustably secured to the spigot 76 via a thread 78. On reaching a predetermined torque the spring is compressed and the clutch slips. After removal of the article which led to the blow which caused this slipping of the clutch, the link can be pressed back into the initial position.
The link 42 must be positioned (suspended) in all embodiments such that the pivot flap suspended on it cannot be drawn into the opening roll(s) 11 and 12.
While the certain embodiments of the invention have been illustrated and described in detail, it is to be understood that the scope of the invention is to be ascertained from the claims which follow. | In an apparatus for opening bales of textile fibers, a deflecting member for the fiber flocks is arranged within the housing and extends in the longitudinal direction of the opening roll. This deflecting member deflects fiber flocks supplied on the one side of the roll into the conveying shaft, at least largely prevents leakage air coming from the other side of the roll, and is able to shift in position under the action of blows which act on it during bale opening, for example blows caused by foreign articles. The deflecting member is pivotally secured in the region of its longitudinal edge adjacent the roll, to respective links for executing pivotal movements about an axis which extends parallel to such longitudinal edge. The opposite ends of the links are in turn pivotally journalled on the housing. Moreover, an extendible and retractable unit is provided for changing over the direction of the deflecting member in accordance with the direction of rotation of the opening roll. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
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BACKGROUND OF THE INVENTION
Low-cost, electric, linear actuators are used in a variety of consumer products, including home appliances and automobiles, to move various components, including lock bolts, valve plates and the like, on the occurrence of an electrical signal.
Common linear actuators include solenoids, wax motors, and DC motors driving gear trains or screw threads. In a solenoid, a metal plunger loosely surrounded by a coil of wire is moved under the influence of a magnetic field produced by an electrical current in the coil. A wax motor employs an electrical current to heat wax contained in a closed volume so that the expanding wax drives a piston out of the volume.
Conventional solenoids and wax motors use a return spring to return the plunger or piston to its unactuated state, and thus require continued power to retain their actuated state. In contrast, small DC (direct current) motors, driving a rack-and-pinion gear or screw and nut, can be reversed by changing the polarity of the driving current, avoiding the need for a return spring and allowing the actuator to retain its actuated state after power is withdrawn.
One problem with DC motor linear actuators is friction in the gear train or screw and nut, particularly when the latter become contaminated during use. The high mechanical advantage typically present in a screw and nut design can cause jamming of the screw and nut at the end of travel under the momentum of the motor.
SUMMARY OF THE INVENTION
The present invention provides an improved DC motor linear actuator in which a screw and nut are replaced by a helical wire spring and a follower. The wire helix may be given a large pitch to prevent excessive force on the follower that might lead to jamming. Further, the flexibility of the wire of the helix can cushion the shock at the end of travel. The open construction of the wire helix resists the build up of contamination that can cause excessive friction. The wire helix further lends itself to simple fabrication and attachment to a motor.
Specifically then, the present invention provides an electrical actuator having an electric motor with a motor shaft rotating about an axis. A wire helix is attached to the shaft to rotate therewith and a helix follower interfits with the wire helix to translate along a path with rotation of the wire helix.
Thus, it is an object of the invention to provide for a simple and cost-effective mechanism for converting the rotary motion of a small DC electric motor into linear motion.
The wire helix may have a lead angle of between 5 and 55 degrees.
Thus, it is an object of the invention to permit relatively large helix lead angles that reduce jamming forces while providing rapid actuation.
The wire of the helix may be sized to flex under a force of the motor when the helix follower is restrained.
It is thus another object of the invention to provide a mechanism that naturally absorbs shocks, for example, when the helix follower reaches stop points, and that readily accommodates axial misalignment.
The wire helix may provide a first portion having a first diameter engaging the helix follower, and a second portion having a second diameter conforming to the diameter of the motor shaft.
Thus, it is an object of the invention to provide a simple means of attaching the helix to the shaft by using helical coils of the wire.
The wire helix may provide a first portion with a lead angle and a second portion with a second lead angle, the first and second portions at different times engaging the helix follower.
Thus it is an object of the invention to provide a simple method of changing the lead angle of the helix, and thus the relative mechanical advantage between the helix and the follower over the length of the helix, such as may be used to change the actuation force, for example, near the ends of motion of the helix follower to prevent jamming.
The second portion may be between the motor shaft and the first portion, and the second lead angle may be larger than the first lead angle.
Thus, it is an object of the invention to provide for a decrease in actuation force when the helix follower is closest to the motor where the helix itself cannot serve, through its elasticity, to cushion the forces generated when the helix follower confronts a stop.
The helix follower may be a bar fitting within the coils of the helix.
Thus it is an object of the invention to provide a simple follower suitable for a wire helix and resistant to jamming.
The helix follower may contact only one side of the helix.
It is thus another object of the invention to provide a helix follower that can decouple from the helix, upon direction reversal, to decrease the load on the motor during its startup.
The helix follower may contact the helix at only a single point.
It is thus another object of the invention to provide a small contact area between the helix follower and the helix that resists capture of contamination.
The helix may be a non-magnetic stainless steel.
It is thus another object of the invention to provide an actuator that is corrosion resistant, durable and which does not divert magnetic flux.
The motor may be a permanent magnet DC motor.
It is thus another object of the invention to provide a simple actuation mechanism that may be used with small motors.
The helix follower may be attached to a switch throw, which may, for example, be a sliding conductive element moving along an axis of the wire helix with the rotation of the helical wire, and pressing outward perpendicularly to the axis of the helical wire against opposed poles.
It is thus an object of the invention to provide a signal indicating the motion of the actuator and to provide a switch compatible with the present system that does not exert a torque on the follower, such as would require friction-increasing stabilization of the helical coil or follower.
The switch throw may be a V-shaped metal spring contacting the poles at the ends of the V.
It is thus another object of the invention to provide a simple throw mechanism that provides balanced outward forces.
The linear electrical actuator may be employed in an appliance latch where the helix follower attaches to a bolt that may extend from one of the housing or a door of the appliance to engage a strike placed on the other of the housing or door.
Thus, it is an object of the invention to provide a low cost latch mechanism suitable for use in appliances that provides for rapid engagement and disengagement and which is stable in engagement and disengagement without the application of electrical power (to reduce electrical consumption), and yet may be readily reversed simply by reversal of power to the motor. These particular objects and advantages may apply to only some embodiments falling within the claims, and thus do not define the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of a washing machine showing the positioning of a latch employing the present invention, such as may extend a bolt to engage a strike in the edge of a door;
FIG. 2 is a front elevational view of a bezel that may serve to attach the latch of FIG. 1 to the housing of the washing machine;
FIG. 3 is a cross-sectional view taken along line 3 - 3 of FIG. 1 showing the latch of FIG. 1 as held by the bezel, and showing tipping of the latch prior to a final installation using screws, such as causes blocking of the bolt that may be detected to signal incomplete installation of the latch;
FIG. 4 is an exploded view of an electrical actuator used in the latch of FIGS. 1-3 showing a DC motor that may turn a helical wire spring engaged by a helix follower bar held below the bolt of the latch;
FIG. 5 is a top plan view of the wire helix and shaft of the motor of FIG. 4 showing changes in pitch and diameter of the wire helix such as changes the lead angle;
FIG. 6 is a cross-section along line 6 - 6 of FIG. 4 showing the orientation of the bar of the helix follower as it engages the helix at a single point on a single side of the helix;
FIG. 7 is a top plan view of a switch having a V-shaped throw compressed between opposing poles of the switch and attached to the bolt of FIG. 4 ;
FIG. 8 is a detailed fragmentary perspective view of one arm of the V-shaped throw showing a bifurcation of the contact surface and a supporting slider tip;
FIG. 9 is a fragmentary cross-section taken along line 3 - 3 of FIG. 1 when the washing machine door is closed showing engagement of the bolt in a strike hole of the door to receive an upwardly extending tooth in the door locking the bolt when the door is lifted during engagement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 , an appliance 10 , such as a washing machine, may have a housing 12 having an opening over which a hinged door 14 may close, for example, to cover a wash basket 16 . The door 14 may be locked when closed to prevent injury to a user during the spin cycle of the washing machine. For this purpose, a front edge of the door 14 may include a strike aperture 18 , which may receive a bolt 20 when the door 14 is in the closed position. The bolt 20 may extend from a latch mechanism 22 positioned within the housing 12 under the control of an electrical signal. As used herein, the term “bolt” may embrace any similar locking element such as a hook, pin, latch bar, shaft or the like.
Referring now to FIGS. 2 and 3 , the latch mechanism 22 may be positioned within the housing 12 behind an aperture 21 through which the bolt 20 (not shown in FIG. 3 ) may extend. The latch mechanism 22 may be held in position by means of a bezel 24 having a central aperture 26 aligning with aperture 21 and a pair of rearwardly extending posts 28 . The posts 28 that may pass through corresponding apertures (not shown) in the housing 12 to be received by sockets 30 molded in the side of the latch housing 23 .
The rearwardly extending posts 28 include upwardly extending teeth 34 that may engage a lip 36 of the socket 30 holding the bezel 24 and housing 23 loosely engaged so as to prevent the housing 23 from dropping downward free of the bezel 24 during assembly. When the posts 28 are received by the socket 30 , screws 38 may be inserted through bases 40 of the sockets 30 to engage threadable portions of the posts 28 .
Tightening of the screws 38 draws the bezel 24 tightly down against the housing 12 and to pull the latch housing 23 upward against the inner surface of the housing 12 . When so tightened, the bolt within the latch housing 23 will extend along a bolt axis 42 that is generally horizontal to be received by the strike aperture 18 of the door 14 when the door 14 is closed. Prior to this tightening, however, gravity will pull the latch housing 23 downward, as shown by a dashed outline of latch housing 23 ′, causing the bolt axis 42 ′ to tip upward. This misalignment will prevent the bolt from fitting into the strike aperture 18 . Blockage of the bolt can be detected by a switch attached to the bolt, as will be described below, providing an error signal to a controller within the appliance 10 indicating a problem with the assembly of the latch housing 23 .
Aperture 26 of the bezel 24 is surrounded by a rearwardly concave and flexible skirt 32 having a curvature with a radius slightly smaller than the radius of curvature of the housing 12 beneath the bezel 24 . Thus, when the bezel 24 is pulled tightly against the housing 12 with the screws 38 , the skirt 32 flexes outward forming a tight seal with the surface of the housing 12 . The housing 23 and bezel 24 are constructed of a flexible thermoplastic material that also provides for electrical insulation and that freely passes magnetic flux.
Referring now to FIG. 4 , the bolt 20 may be driven by and form part of a linear actuator 44 comprising a permanent magnet DC motor 46 having a shaft 48 that may rotate in one of two directions according to the polarity of electrical voltage applied to the motor 46 over motor leads 50 . Attached to the shaft 48 and axially aligned therewith is a wire helix 52 , both of which are generally parallel to the bolt axis 42 .
Paddles 54 , extending downward from the bolt 20 , flank the left and right side of the wire helix 52 and receive a transversely extending metal bar 56 passing through corresponding holes 58 in each of the paddles 54 to intersect the wire helix 52 and to be held captive by its coils. The paddles 54 and bar 56 provide a helix follower that moves along the axis 42 with rotation of the wire helix 52 .
The wire helix 52 is preferably a spiral of spring-tempered stainless steel wire following a three-dimensional curve that lies on a cylinder of a defined diameter and having a central axis parallel to axis 42 . The wire of the wire helix 52 will have a defined angle with respect to a plane perpendicular to the axis 42 termed its lead angle. The lead angle may be controlled simply by spacing between wire coils along the axis of the wire helix 52 .
Referring now to FIG. 5 , the wire helix 52 provides a number of different pitches and diameters and thus different lead angles, where lead angle 65 , as described above, is the angle between a plane orthogonal to the axis 42 and the wire of the helix 52 . For a given helix diameter, the lead angle will increase as the pitch increases. In a first region 60 , near where the wire helix 52 is attached to the motor shaft 48 , the wire helix 52 is given a small diameter 62 so that it may be press fit and welded directly to the shaft 48 . The pitch 64 in this first region 60 is such that the windings of the wire helix 52 abut each other and thus is approximately equal to the diameter of the wire of the wire helix 52 . Here the lead angle may be relatively low.
In a second region 66 , displaced from the motor 46 by region 66 , the diameter 61 of the wire helix 52 increases, while the pitch 68 is retained at pitch 64 for the purpose of stable transition.
In a next region 70 proceeding outward from the motor 46 , the pitch is abruptly increased to an expanded pitch 72 (increasing the lead angle) and then, at succeeding region 74 encompassing the remainder of the wire helix 52 , the pitch decreases slightly to a reduced pitch 76 (and reduced lead angle), both lead angles being typically greater than five degrees and less than fifty-five degrees. These regions 70 and 74 provide drive surfaces for the helix follower of the bar 56 and create a relatively large opening between coils of the wire helix 52 such as to resist entrapment of contaminants.
Referring also to FIG. 4 , when the bolt 20 is fully extended and the bar 56 is in the region 74 , the bolt 20 may hit a stop 78 . A PTC thermister (not shown) may be placed in series with the motor to prevent over-current of the motor 46 when the motor 46 stalls, but even with current limiting, the interaction of the bolt 20 with the stop 78 can produce a relatively high instantaneous torque (and resulting actuation force) caused by the rapid deceleration of rotating mass of the motor 46 . However, any jamming of the bar 56 and wire helix 52 , such as might prevent reversal of the wire helix 52 , is forestalled by the natural compliance of the wire helix 52 , which compresses slightly to slow the deceleration of the motor 46 decreasing the peak torque.
When the motor 46 is reversed and the bolt 20 is drawn inward against a second stop 80 adjacent to the motor 46 , there is less length of the wire helix 52 to act as a spring to slow the deceleration of the motor 46 . In this case, the increased lead angle of the wire helix 52 in region 70 , serves to reduce the axial force and to prevent jamming.
Referring now to FIG. 6 , the bar 56 of the helix follower may be installed at an angle with respect to the axis 42 to contact the coils of the wire helix 52 at a single point only, thus reducing potential entrapment of contaminants. Further, the angle of the bar 56 is such that the bar 56 , at any time, contacts only one side of the wire helix 52 . This allows the load of the bolt 20 to be decoupled from the wire helix 52 upon change in direction of the motor 46 , preventing stalling of the starting motor 46 in a position of low torque. This decoupling also allows the motor to start up in a reversed direction with reduced load to gain speed before the bar 52 recontacts the side of the wire helix 52 . The bar 56 may be molded into paddles 54 or may be a metal bar held by the paddles providing improved wear resistance. In one embodiment, shown in FIG. 4 , the bar 56 may be surrounded with a sleeve 57 (for example a self-lubricating plastic material) that provides a lower-friction contact between the bar 56 and the helix 54 by action of the sleeve 57 rolling about the bar 57 .
Referring now to FIGS. 4 and 7 , extending axially rearward from the bolt 20 , is a metallic V-shaped throw 84 . The throw 84 has outwardly diverging arms 88 that are flexible and compressed between opposed surfaces of pole 90 on one side, and pole 92 or 94 on the opposite side as the bolt 20 and throw 84 move axially throughout the length of travel of the bolt 20 . The pole 90 is continuous while pole 92 and 94 occupy opposite axial ends of a track 96 . Electrical continuity exists from the pole 90 through spring throw 84 to pole 92 when the bolt 20 is fully retracted and from the pole 90 through spring throw 84 to pole 94 when the bolt 20 is fully extended. Electrical continuity is broken when the bolt 20 is neither fully retracted nor fully extended. In this way, three distinct signals may be generated, one each for when the bolt is fully extended, fully retracted and in transition. Referring now also to FIG. 8 , an outwardly convex dimple 102 may be placed at the ends of the arms 88 where they ride against the poles 90 , 92 , or 94 (only pole 90 is shown), to provide a contact surface. The dimple 102 may include an axial groove, 103 bifurcating the surface of the contact where it connects with one of the poles 90 , 92 , or 94 to provide improved contact reliability.
The vertex of the V-shaped throw 84 is pivotally attached to a downwardly extending pivot pin 86 on the bolt 20 so that the throw 84 is self-aligning between pole 90 and pole 92 and 94 on track 96 . Referring now also to FIG. 8 , inwardly extending tabs 98 are formed on the ends of the arms 88 to ride on tracks 100 positioned between the ends of the arms 88 . The tabs 98 help stably locate the ends of the arms 88 against rotational movement. It will be understood from this description that there is no rotational torque exerted by the V-shaped throw 84 on the bolt during switching action such as might tend to cam the bolt 20 or divert the wire helix 52 off axis.
Referring now to FIGS. 1 and 9 , when the bolt 20 is inserted through the strike aperture 18 in the door 14 and the door 14 is lifted upward, as indicated by arrow 104 , a tooth 106 formed in the door 14 behind the strike aperture 18 may engage a corresponding socket 108 formed in the lower side of the bolt 20 . The interengagement of the tooth 106 and socket 108 prevents force on the door 14 possibly sufficient to bend the bolt 20 , or from disengaging the bolt 20 from the strike aperture 18 .
It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments, including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. | An electrical linear actuator employs a reversible motor driving a helical wire spring. The coils of the spring engage a follower that moves along the axis of the spring with rotation of the motor to provide linear motion. This actuator may be used as a linear drive in an appliance lock. | 3 |
RELATED APPLICATIONS
This application claims benefit of provisional application Serial No. 60/193,045 filed on Mar. 29, 2000.
BACKGROUND OF THE INVENTION
The field of the invention is nuclear magnetic resonance imaging methods and systems. More particularly, the invention relates to the production of brain function images.
Any nucleus which possesses a magnetic moment attempts to align itself with the direction of the magnetic field in which it is located. In doing so, however, the nucleus precesses around this direction at a characteristic angular frequency (Larmor frequency) which is dependent on the strength of the magnetic field and on the properties of the specific nuclear species (the magnetogyric constant gamma γ of the nucleus). Nuclei which exhibit this phenomena are referred to herein as “spins”.
When a substance such as human tissue is subjected to a uniform magnetic field (polarizing field B 0 ), the individual magnetic moments of the spins in the tissue attempt to align with this polarizing field, but precess about it in random order at their characteristic Larmor frequency. A net magnetic moment M z is produced in the direction of the polarizing field, but the randomly oriented magnetic components in the perpendicular, or transverse, plane (x-y plane) cancel one another. If, however, the substance, or tissue, is subjected to a magnetic field (excitation field B 1 ) which is in the x-y plane and which is near the Larmor frequency, the net aligned moment, M z , may be rotated, or “tipped” into the x-y plane to produce a net transverse magnetic moment M t , which is rotating, or spinning, in the x-y plane at the Larmor frequency. The practical value of this phenomenon resides in the signal which is emitted by the excited spins after the excitation signal B 1 is terminated. There are a wide variety of measurement sequences in which this nuclear magnetic resonance (“NMR”) phenomena is exploited.
When utilizing NMR to produce images, a technique is employed to obtain NMR signals from specific locations in the subject. Typically, the region which is to be imaged (region of interest) is scanned by a sequence of NMR measurement cycles which vary according to the particular localization method being used. The resulting set of received NMR signals are digitized and processed to reconstruct the image using one of many well known reconstruction techniques. To perform such a scan, it is, of course, necessary to elicit NMR signals from specific locations in the subject. This is accomplished by employing magnetic fields (G x , G y , and G z ) which have the same direction as the polarizing field B 0 , but which have a gradient along the respective x, y and z axes. By controlling the strength of these gradients during each NMR cycle, the spatial distribution of spin excitation can be controlled and the location of the resulting NMR signals can be identified.
The imaging of brain functions with magnetic resonance imaging systems has been done using fast pulse sequences. As described by J. Frahm et al in “Dynamic MR Imaging of Human Brain Oxygenation During Rest and Photic Stimulation”, JMRI 1992:2:501-505; K. Kwong et al in “Dynamic Magnetic Resonance Imaging of Human Brain Activity During Primary Sensory Stimulation” Proc. Natl. Acad. Sci USA Vol. 89, pp 5675-5679, June 1992 Neurobiology; and S. Ogawa et al, “Intrinsic Signal Changes Accompanying Sensory Stimulation: Functional Brain Mapping Using MRI”, Proc. Natl Acad. Sci USA Vol. 89, pp. 5951-5955, June 1992 Neurobiology, these prior methods use a difference technique in which a series of image data sets are acquired with an EPI pulse sequence while a particular function is being performed by the patient, and a baseline image data set is acquired with no patient activity. The baseline data set is subtracted from the series of data sets to produce difference images that reveal those parts of the brain that were active during the performance of the function. These difference images may be displayed in sequence to provide a cine display of the activity-induced brain functions. In this case the fMRI parameter which distinguishes active and inactive regions of the brain is signal amplitude difference.
The difference in NMR signal level produced By regions of the brain that are active and those that are inactive is very small. The difference is believed to result from the increase in oxygen supply to active portions of the brain which decreases the susceptibility differential between vessels and surrounding tissues. This allows an increase in the phase coherence of spins and a resulting increase in NMR signal level. However, this difference in signal level is only 2 to 4 percent (at 1.5 Tesla) and is masked by system noise, and artifacts caused by patient motion, brain pulsatility, blood flow and CSF flow.
An improved method for determining which regions of the brain are active is described in U.S. Pat. No. 5,603,322. Rather than relying on signal amplitude differences as a measure of activity, the disclosed method correlates the changes in the signal level over the duration of the study with the changes in the function being performed, or stimulation applied to the subject. The signal pattern of regions that are active in response to the function or stimulation correlates highly with the function or stimulation pattern and these regions are designated “active”. In this case the fMRI parameter which distinguishes active and inactive regions of the brain is a correlation number.
As one uses fMRI to answer more complex questions (for example, the difference in activation pattern between two or more tasks), the relative difference in signal intensity between the conditions becomes even less than 2 to 5 percent. In addition, it has been discovered that the fMRI signal from unactivated regions in the brain can vary by as much as 1 percent. Before any definitive conclusions can be made about the fMRI results in a study, therefore, the signal's reliability and variability both within a subject and between subjects must be determined.
To understand the statistical reliability of an estimate such as the correlation coefficient, suppose that the correlation coefficient value of 0.65 were obtained between a pixel time course (70 points) from the sensorimotor cortex and an idealized reference waveform representing the “on/off” cycle of bilateral finger tapping. If there were a 95% probability that the correlation coefficients would lie between 0.64 and 0.66, then the correlation coefficient of 0.65 could be considered to be very reliable. However, if the correlation probability distribution were evenly spread between −1 and 1, then the obtained correlation coefficient would not be reliable.
Hence, some measure is needed to assess the statistical accuracy and reliability of the correlation coefficient or of any other statistical parameter of interest used in fMRI.
Traditionally, the reliability of fMRI data has been obtained by using test-retest analysis. As its name suggests, in test-retest analysis, the same task is repeated several times using identical imaging parameters. The data obtained are then processed, and the reliability of the data sets is measured using a number of different techniques. Test-retest analysis assumes that the task activation paradigm can be repeated a number of times under identical conditions, without any learning or habituation by the subject to alter neuron firing. In each of the test-retest analysis, the experiment must be repeated several times (three or more) to obtain the reliability criteria.
Although this method might be effective in analyzing simple motor or visual tasks, for more complex tasks, this assumption will not be valid. Even for a simple finger-tapping experiment, not only must the imaging parameters be identical for each of the scans, but also the stimulus-related parameters, including the finger-tapping rate and the on/off cycle timing, must be the same. Any deviation from the specified finger-tapping rate or the on/off cycle in any of the scans would result in erroneous conclusions. With the increase in time of scanning, even motivated subjects are likely to move their heads by at least a few millimeters. Head motion is even more severe for diseased or young subjects, further deteriorating reliability parameters calculated using the test-retest methodology.
SUMMARY OF THE INVENTION
The present invention is a method of producing fMRI images with a designated level of confidence in its depiction of brain activity. More particularly, the method includes: acquiring an fMRI data set; creating a plurality of truncated data sets using a corresponding plurality of different sub-sets of the acquired fMRI data set; calculating an fMRI parameter for the acquired fMRI data set and each of the truncated data sets; determining the distribution of the fMRI parameter calculated from the truncated data sets; and determining a confidence level indicator for the fMRI parameter calculated from the acquired fMRI data set.
A general object of the invention is to improve the reliability of an fMRI image based on a measured fMRI parameter. If the measured fMRI parameter is a correlation number calculated for each image voxel, for example, active regions in the brain are indicated by modulating the intensity or color of corresponding pixels in a display when the correlation number exceeds preset threshold values. The present invention produces a confidence level indicator for each correlation number, and this may be used as a second threshold to exclude voxels which fail to meet the confidence level threshold. For example, even though a voxel has a correlation number of 0.65 which meets the initial criteria as an active voxel, it may not be displayed as active if its confidence level is only 35%.
The foregoing and other objects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims herein for interpreting the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an NMR system which employs the present invention;
FIG. 2 is a graphic representation of the EPI pulse sequence used to practice the present invention on the NMR system of FIG. 1;
FIG. 3A is a pictorial representation of the NMR image data acquired with the pulse sequence of FIG. 2;
FIG. 3B is a graphic representation of a time domain voxel vector which forms part of the data set of FIG. 3A;
FIG. 4 is a graphic representation of a waveform for an exemplary voxel vector;
FIG. 5 is a graphic waveform of the reference waveform representative of the subject activity which produced the waveform of FIG. 4;
FIG. 6 is a histogram of the jackknife correlation values produced in accordance with the present invention; and
FIG. 7 is a flow chart of the steps employed to produce an fMRI image according to the present invention.
GENERAL DESCRIPTION OF THE INVENTION
The present invention employs a method known in the art as the “jackknife” resampling technique to calculate confidence intervals for fMRI parameters produced from a study. The theory underlying this method is as follows. Suppose that x={x 1 , x 2 , x 3 . . . , x N } is an independent, identically distributed sample data set from a population with distribution F. In almost every statistical data analysis, the sample x is studied to estimate a certain unknown parameter, θ(F), associated with the distribution F. A statistic Q(x), is usually calculated from data set x to estimate θ(F). A statistically quantitative number of the deviation of Q(x) from θ(F) is desirable to gauge the reliability of the data. For many applications, the calculated statistic θ(x) is approximated as a Gaussian distribution with a (1−α) 100% confidence interval for θ(F). This will be true for a large number of estimators, provided that the sample size, N, is large enough to be asymptotically normal, and an appropriate confidence interval (or any other parameter) for θ(F) can be obtained, in addition to the calculated statistics, Q(x).
The basis of the jackknifing technique lies in creating the distribution graph of a large population from only a small sample, when traditional methods are either cumbersome or unusable. The original sample is manipulated by repeatedly omitting a small number of data points, always different, thus obtaining a large quantity of various samples. For each truncated data set, the statistic in question is recalculated, and then the variability of the entire group of pseudo-samples can be found when analyzing the results in a probability distribution. One particular advantage with using this technique is that data are analyzed without using a priori assumptions, especially those about distribution. Nor is it limited to analyzing, for example, only Gaussian distribution. Therefore, few estimations and variables are used unnecessarily, resulting in a higher confidence level. The jackknifed data set is simply an approximation of the theoretical distribution of the observed data and is analogous to treating the observed sample as if it exactly represented the entire population.
In the present invention the jackknife technique is applied to calculate a confidence level indicator for the fMRI parameter produced from the fMRI data acquired during the study. Using the above nomenclature, θ(F) may be either the mean signal increase measured at each voxel during task activation or the correlation coefficient measured at each voxel. The jackknife method produces a confidence level from 0% to 100% which indicates the reliability of each measured fMRI parameter.
The calculated confidence level may be used in a number of ways. The confidence level numbers may simply be displayed along with an indication of their associated fMRI image voxels. On the other hand, the confidence levels may be used as a second test to establish whether a particular voxel was active or inactive during the study. In this case, a confidence level threshold is set (e.g. 85%), and if this level is not met or exceeded, the voxel is indicated as “inactive”, even though its fMRI parameters (e.g. correlation number) exceeds the established threshold for an active voxel.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an MRI magnet assembly 10 has a cylindrical bore tube 12 extending along a z-axis 13 for receiving a supine patient 14 supported on a table 16 . The table 16 may move in and out of the bore tube 12 so as to position the patient 14 along the z-axis 13 within the volume of the bore tube 12 .
Coaxially surrounding the bore tube 12 is a whole-body RF coil 18 for exciting the spins of the patient 14 into resonance, as has been described. Whole-body gradient coils 20 surround both the bore tube 12 and the RF coil 18 and are also coaxial with the z-axis 13 , to provide x, y and z gradient fields G x , G y and G z as required for MRI imaging. The gradient coils 20 are driven by gradient amplifiers (not shown). The polarizing magnetic field B 0 , aligned with the z-axis 13 is generated by a superconducting magnet coil 28 coaxial with but outside the bore tube 12 , the RF coil 18 and the gradient coils 20 . The superconducting magnet coil 28 has no external power supply but operates on an initial current which continues unabated in the zero resistivity windings of the superconducting magnet coil 28 .
Interposed between the superconducting magnet coil 28 and the gradient coil 20 is a set of shim coils 30 which are used to correct the homogeneity of the polarizing field B 0 as is understood in the art. A set of mechanical linkages and insulators (not shown) rigidly connect each of these coils 18 , 20 , 28 and 30 together to the bore tube 12 so as to resist relative motions generated by the interaction of their various electromagnetic fields.
When a local coil assembly 8 is used in a general purpose system such as that described above, the whole-body gradient coils 20 and whole-body RF coil 18 are disconnected. The local coil assembly 8 is connected to the x, y and z gradient amplifiers (not shown) on the NMR system and it is connected to the system's transceiver through a transmit/receive switch. The preferred embodiment employs a 3 Tesla MRI system manufactured by Bruker Analytische MeBtechnik GmbH and sold under the trademark BIOSPEC 30/60.
Because the gradient fields are switched at a very high speed when an EPI sequence is used to practice the preferred embodiment of the invention, local gradient coils are employed in place of the whole-body gradient coils 139 . These local gradient coils are designed for the head and are in close proximity thereto. This enables the inductance of the local gradient coils to be reduced and the gradient switching rates increased as required for the EPI pulse sequence. The local gradient coil assembly 8 also includes a local brain RF coil. In the preferred embodiment, it is a 16 element bandpass endcapped birdcage coil. This brain RF coil is designed to couple very efficiently to the brain of the subject and less efficiently to the lower part of the head. This results in improved brain image quality compared with larger general purpose head coils that couple uniformly to the entire head as well as the neck. An RF shield surrounds the local brain coil and interior to the local gradient coil. This shield isolates RF radiation from the local gradient coil. The shield is designed to avoid perturbation of time varying gradient fields. For a description of these local gradient coils and the RF coil which is incorporated herein by reference, reference is made to U.S. Pat. No. 5,372,137 filed on Jan. 19, 1993 and entitled “NMR Local Coil For Brain Imaging”.
The EPI pulse sequence employed in the preferred embodiment of the invention is illustrated in FIG. 2. A 90° RF excitation pulse 250 is applied in the presence of a G z slice select gradient pulse 251 to produce transverse magnetization in a slice through the brain ranging from 4 to 25 mm thick. The excited spins are rephased by a negative lobe 252 on the slice select gradient G z and then a time interval elapses before the readout sequence begins. A total of 64 separate NMR echo signals, indicated generally at 253 , are acquired during the EPI pulse sequence. Each NMR echo signal 253 is a different view which is separately phase encoded to scan k y −space from k y =−32 to k y =+32 in monotonic order. The readout sequence is positioned such that the view acquired at k y =0 occurs at the desired echo time (TE). While echo times may range from TE=20 to 120 ms, in brain studies the best functional images have been obtained with echo times of 40 to 50 ms.
The NMR echo signals 253 are gradient recalled echo's produced by the application of an oscillating G x readout gradient field 255 . The readout sequence is started with a negative readout gradient lobe 256 and the echo signals 253 are produced as the readout gradient oscillates between positive and negative values. A total of 64 samples are taken of each NMR echo signal 253 during each readout gradient pulse 255 . The successive 64 NMR echo signals 253 are separately phase encoded by a series of G y phase encoding gradient pulses 258 . The first pulse is a negative lobe 259 that occurs before the echo signals are acquired to encode the first view at k y =−32. Subsequent phase encoding pulses 258 occur as the readout gradient pulses 255 switch polarity, and they step the phase encoding monotonically upward through k y space.
At the completion of the EPI pulse sequence, therefore, 64 separate frequency encoded samples of 128 separately phase encoded NMR echo signals 253 have been acquired. This 64×64 element array of complex numbers is Fourier transformed along both of its dimensions (k y and k x ) to produce a 64×64 element array of image data that indicates the NMR signal magnitude along each of its two dimensions (y and x).
A complete scan is performed in which the EPI pulse sequence is repeated 90 times to acquire time course NMR data for 90 images. The EPI pulse sequences are spaced apart in 2 to 3 seconds intervals such that the entire time course acquisition spans a 4 to 6 minute time period. During that time period the subject is asked to perform a specific function in a predetermined pattern, or a stimulus is applied to the subject in a predetermined pattern. For example, the subject may be instructed to touch each finger to his thumb in a sequential, self-paced, and repetitive manner, or the subject may be subjected to a sensory stimulus such as a smell or visual pattern in a periodic manner. More than one such experiment may be conducted during the scan by varying the repetition rate, phase, or frequency, of the applied stimulus or performed function so that they can be discriminated on the basis of the frequency difference.
The acquired NMR data is processed in the conventional manner to produce an NMR image data set for 90 images. As explained above, a two dimensional Fourier transformation is performed and the resulting NMR image data set is stored for further processing according to the present invention.
Referring to FIG. 3A, this NMR image data set is organized as a set of 64×64 element 2D arrays 300 in which each element stores the magnitude of the NMR signal from one voxel in the scanned slice. Each array 300 can be used to directly produce an anatomical image of the brain slice for output to the video display 118 . While each array 300 is a “snap shot” of the brain slice at a particular time during the time course study, the NMR image data set may also be viewed as a single 64×64×90 3D fMRI data array 301 in which the third dimension is time.
The time course NMR image data for one voxel in the array 301 is referred to herein as a time course voxel vector. One such 90 element vector is illustrated in FIG. 3A by the dashed line 302 . Each time course voxel vector 302 indicates the magnitude of the NMR signal at a voxel in the image slice over the time course study. It may be used to produce a graphic display as shown in FIG. 3 B. The resulting time domain voxel graph 303 reveals very clearly variations in the activity of the brain in the region of the voxel. Regions which are responsive to a sensory stimulus, for example, can be located by identifying time domain voxel graphs which vary at the same repetition rate as the applied stimulus.
Either of two procedures for producing brain function images can be employed using the time domain data in the fMRI image data set 301 . The first is a simple difference image. With this procedure the operator is prompted to select at least two of the 2D arrays 300 in the data set 301 . The operator selects one 2D array 300 that is acquired when stimulation is applied and a second 2D array 300 that is acquired when there is no stimulation. A difference image is then produced by subtracting the values of their corresponding voxels. Each voxel in the difference array indicates the difference in NMR signal strength produced by the corresponding region of the brain when the stimulation is applied and removed from the subject. This brain function image may be superimposed on the anatomical brain image to indicate where brain activity is occurring. This superimposition can be a simple addition of corresponding pixel values in the anatomical image and the brain function image to produce a brightness image. In the alternative, the brain function amplitude difference values can be used to control the intensity of a different color or to modulate the color of the image pixels. Regardless of which method is used to modulate the anatomic image with the brain activation image, the present invention is an improvement in which a confidence level is calculated for each difference value in the brain function image before they are used to indicate brain function.
A second, and more preferred method for producing a brain function image produces a correlation image from the fMRI image data set 301 . A reference voxel vector such as that shown in FIG. 5 is manually synthesized to represent the ideal response of the brain to the selected stimulation or function pattern. The 90 element reference voxel vector is correlated with each of the time domain voxel vectors 300 in the NMR image data set 301 . This correlation operation may be performed in different ways. The objective, however, is to measure the degree to which each time domain voxel vector resembles, or matches, the pattern of the reference voxel vector. For a more detailed description of the preferred correlation method, reference is made to the above-cited U.S. Pat. No. 5,603,322 which is incorporated herein by reference. The correlation magnitudes that result are scaled to a range of 0 to 1.0. These correlation values may be used to modulate the brightness or color of pixels as described above to indicate brain activity. The present invention is an improvement in which the confidence level is calculated for the correlation values before they are used to indicate brain activity.
In the preferred embodiment of the invention the fMRI data set 301 is examined to calculate confidence intervals for the calculated correlation values. The signal produced by the 90 successive amplitude values in one exemplary voxel vector is depicted in FIG. 4 and the idealized reference voxel vector is depicted in FIG. 5 . The correlation of these two waveforms as calculated above is 0.8436. The preferred embodiment of the present invention is implemented by a program which produces a confidence interval for this correlation value and the correlation values for each of the other voxel vectors 302 in the data set 301 .
Referring particularly to FIG. 7, a loop is entered in which a 90 element voxel vector 301 is selected at process block 320 . A second loop is then entered at process block 322 in which 85 elements are randomly selected from this voxel vector. The corresponding 85 elements are also selected from the reference vector as indicated at process block 324 , and the correlation between these two 85 element vectors is calculated at process block 326 . This “jackknife” correlation value is stored in a table. As determined at decision block 328 , the system loops back to randomly select another 85 elements and calculate the corresponding jackknife correlation value. This is performed 1000 times to yield 1000 jackknife correlation values.
The particulars of this process are as follows. Each selected voxel vector 302 is entered into a table, and next to it is placed a series of 90 numbers generated by the computer's random function. The latter numbers are then sorted in ascending order, each being moved with the corresponding value from the voxel vector 302 . The reference voxel vector is also changed accordingly. Once rearranged, the first 85 fMRI elements, having been chosen randomly from 90 data points, are cross-correlated with the respective reordered reference voxel vector. Because the random function produces a different series of numbers each time, the sequence of data points is always different. Therefore, the 1000 sets of data all vary slightly. From a small sample, the jackknife process produces an entire theoretical population of data, from which a reliable distribution and variability may be obtained. Thus, from only 90 images, the jackknife technique generates 4.395×10 7 (90!/85!5!) unique samples, each containing 85 elements.
If all were perfect, each calculated correlation value would be the same (e.g. 0.8436 in the example voxel vector in FIG. 4 ). But of course, such is never the case and the correlation values will extend over a range. A histogram of the jackknife correlation values calculated for the voxel vector of FIG. 4 and reference vector of FIG. 5 is depicted in FIG. 6 . The 1000 jackknife correlation values are distributed primarily from 0.82 to 0.86. As indicated at process block 330 , the mean of these jackknife correlation values is calculated as well as the standard deviation. These statistical values provide the basis for calculating a confidence level indicator at process block 332 . In the preferred embodiment a confidence interval is calculated.
The process continues, as determined at decision block 334 , to calculate confidence intervals for each voxel vector 302 in the data set 301 . When these calculations are completed, therefore, each voxel vector 302 has associated with it a correlation value which is indicative of the degree of brain activity and a confidence interval which is a statistical indication of the accuracy of this correlation value.
Referring still to FIG. 7, in the preferred embodiment the fMRI image is modified using the calculated confidence intervals as indicated at process block 336 . More particularly, even though the correlation value for a voxel vector is high enough to indicate that its image pixels are active, if its corresponding confidence interval does not exceed a threshold value, the image pixels are not modulated to indicate brain activity. This confidence interval threshold may be preset for each scan and typically might be set to around e.g. 85%.
With the use of confidence intervals of the correlation coefficient distributions, fMRI activation maps are obtained that have equal statistical significance at each pixel. Thus, the intrinsic variability of the impulse response function and the different noise levels present at each pixel is taken into account while generating the statistical significance of the activation map. This is in contrast to applying a fixed threshold value for the correlation coefficients, where it is assumed that both the impulse response function and the noise are constant among all the pixels. | An EPI pulse sequence is performed by an MRI system which acquires images of the brain over a time interval during which the subject performs a function or is stimulated in a pattern. An fMRI parameter is calculated for each voxel which indicates those regions of the brain that are active during the study. The same acquired NMR data is employed in a jackknife method for recalculating the fMRI parameter many times and from the distribution of the recalculated values a confidence level indicator is produced. Low confidence level indicators are used to exclude regions which are otherwise indicated as active. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates to a toughened glass-ceramic compound comprising cordierite.
BACKGROUND OF THE INVENTION
[0002] In high temperature application, crystalline materials often have superior resistance to thermal deformation compared to their glassy counterparts. Crystalline articles are often produced by sintering. Sintering has certain disadvantages, including void creation and the need for pressing. In contrast, glassy articles may be cast in a nearly void-free state. Unfortunately, glassy materials can thermally deform well below their theoretical melting point.
[0003] Prior art teaches that crystalline grains can be annealed from an initially glassy material, thereby forming a glass-ceramic. Glass-ceramics can have improved resistance to thermal deformation compared to the glass. The glass is first shaped, usually above the liquidus temperature, and then annealed above a nucleation temperature. The fluid nature of the glass above its liquidus can permit it to be shaped by casting. The nucleation temperature is a temperature at which crystals begin to form and grow within the glass. The selected nucleation temperature should be below a temperature at which the glass would thermally deform. During annealing, crystalline grains nucleate, begin to grow, and ultimately comprise a majority of the material. High melting point compounds, such as titanium dioxide, can facilitate nucleation. Below its melting temperature, a crystal typically has significantly lower thermal deformation than a corresponding glass. Glass-ceramics have been used in a variety of applications where resistance to thermal deformation is an issue.
[0004] One such glass-ceramic composition includes a predominately crystalline phase comprising cordierite. Cordierite, a magnesium aluminum silicate, was described by S. D. Stookey in U.S. Pat. No. 2,920,971, and may be used in refractory applications. Cordierite glass-ceramics have good hardness and resistance to thermal deformation, but they can suffer from a high coefficient of thermal expansion (CTE) and have only average fracture toughness. For example, one cordierite glass-ceramic has a fracture toughness of 2.2 MPa·m 0.5 and an average CTE of 57×10 −7 /° C. over the temperature range from 25-1000° C. Poor fracture toughness permits cracks to form and propagate, which can cause an article to shatter or break under stress. A high CTE decreases resistance to thermal shock. Low fracture toughness and high CTE limit the utility of cordierite glass-ceramics.
[0005] Silicon nitride, Si 3 N 4 , has been used in applications requiring lower CTE and higher fracture toughness. Silicon nitride has a CTE of about 30×10 −7 /° C. and a fracture toughness around 6 MPa·m 0.5 . Silicon nitride also has better high temperature capabilities than most metals combining high strength, creep resistance, and oxidation resistance. These properties have allowed silicon nitride to replace metals in turbine and reciprocating engines, and as engine components, bearings and cutting tools. In addition, its low thermal expansion coefficient provides good thermal shock resistance compared with most ceramic materials. Negatively, silicon nitride can be difficult to produce as a fully dense material (often requiring hot pressing), does not readily sinter, may oxidize under certain conditions, and cannot be heated over 1850° C. because it dissociates into silicon and nitrogen. These deficiencies cause silicon nitride components to be expensive, thereby limiting the applications using silicon nitride components.
[0006] A need exists for a replacement material to silicon nitride. The material should be relatively inexpensive and easy to produce. Preferably, it should be amenable to molding and should combine low CTE with high fracture toughness.
SUMMARY OF THE INVENTION
[0007] The present invention describes an internally nucleated cordierite glass-ceramic. The cordierite glass-ceramic combines good fracture toughness with low CTE. Additionally, the present invention can be cast as a liquid, but after annealing it is substantially crystalline, and has high hardness, high Young's modulus, good thermal stability, high strength, low density and good dielectric properties.
[0008] The cordierite glass-ceramic of the present invention has a microstructure comprising interlocking crystalline phases dominated by a first phase consisting essentially of elongated cordierite grains and a second phase having an elongated or acicular structure. A third phase may also be present and may comprise a crystalline ceramic capable of twinning. The energy associated with twinning can further increase fracture toughness.
[0009] The glass-ceramic of the present invention is directed to an internally nucleated cordierite glass-ceramic. The cordierite glass-ceramic combines high fracture toughness in the range of 2.5 to 6.0 MPa·m 0.5 ; low thermal expansion coefficient in the range of 20-50×10 −7 /° C. in the temperature range 25-1000° C.; high hardness with a Knoop value greater than 800; high Young's Modulus with a value greater than 10 GPa; thermal stability to a temperature of 1200° C. and above; high strengths generally above 200 MPa; low density from about 2.5-2.9 g/cc; and good dielectric properties with high resistivity, low dielectric constant and loss tangent. The invention is further directed to a cordierite glass-ceramic where high fracture toughness is achieved by producing a microstructure of interlocking crystal phases in which cordierite predominates and where at least one phase is highly elongated or acicular. Optionally, an additional phase is desirable that is capable of lamellar twinning, for example without limitation, enstatite (MgSiO 3 ) and/or anorthite (CaAlSi 2 O 8 ). Twinning is known to enhance fracture toughness.
[0010] In another embodiment, the cordierite glass-ceramic of the present invention has a CTE of less than 35×10 −7 /° C. and a fracture toughness about up to 6.0 MPa·m 0.5 . The low CTE results in improved thermal shock resistance. Higher fracture toughness lowers rates of crack initiation and propagation, thereby reducing risks of fracture. The low CTE and increased fracture toughness of cordierite glass-ceramics of the present invention are comparable to silicon nitride. Advantageously, cordierite glass-ceramics may be precision cast from a fluid glassy state, do not require hot pressing and, compared to silicon nitride, have lower densities and superior oxidation resistance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a microstructure of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] A toughened, low CTE cordierite glass-ceramic includes a plurality of phases at least one of which is acicular. A glass-ceramic includes any material that is formed when a substantially glassy material is annealed at elevated temperature to produce a substantially crystalline material. Annealing induces nucleation of one or more crystalline phases. Nucleation may be accelerated by seeding the glass with high melting point compounds such as titanium dioxide. Annealing is completed when the intended level of crystallinity is reached, typically in excess of eighty percent and more typically greater than ninety percent.
[0013] The glass-ceramic of the present invention includes a plurality of crystalline phases. Importantly, any residual glass must not form a continuous phase throughout the material. To this end, crystallinity should be at least about 85% of the volume and preferably more than 90% crystalline. A typical toughened, low CTE cordierite glass-ceramic will have residual glass of less than 5% by volume. The crystalline phases include at least two interlocked phases.
[0014] A first crystalline phase comprises elongated grains of cordierite. A second crystalline phase is acicular and includes titanates, such as, for example magnesium titanates, aluminum titanates or combinations thereof. Optionally, a third phase may be present and preferably includes ceramic compounds capable of lamellar twinning. Twinning ceramic compounds include enstatite (MgSiO3) and plagioclase feldspars, such as anorthite (CaAl 2 Si 2 O 8 ). FIG. 1 shows a micrograph of such a glass ceramic of the present invention, including dark crystals of hexagonal cordierite, white crystals of acicular magnesium aluminum titanate, and grey crystals of anorthite.
[0015] The glass-ceramic comprises from 50-80 volume percent cordierite. Advantageously and unlike silicon nitride, cordierite is inherently resistant to oxidation because it is already an oxide. The cordierite phase includes a hexagonal crystal structure of 6/m 2/m 2/m. Cordierite grains should have an aspect ratio of at least 2:1 and preferably at least about 5:1. The elongated structure may facilitate interlocking with other crystal grains. Furthermore, elongated cordierite grains may permit the second phase to grow along the elongated cordierite grain boundaries, thereby increasing the acicularity of the second phase.
[0016] The glass-ceramic comprises from 8-20 volume percent of an acicular second phase. During annealing of the glass, second phase crystallization begins around 850° C. culminating in cordierite formation near 1100° C. Further annealing permits the second phase to grow along cordierite grain boundaries. The second crystalline phase should have an aspect ratio of at least 5:1. Acicularity as high as 20:1 has been observed. No theoretical upper limit of acicularity is expected. The measured acicularity will obviously be lower than the actual acicularity unless the second phase falls along the plane of the micrograph. The acicular structure of second phase grains permits such grains to interact with a larger number of other phases or grains. The second phase comprises compounds that inherently grow crystals in acicular, lath-like morphologies. Compounds include, for example, titanates of magnesium and aluminum. Other suitable compounds are known to those skilled in the art. Fluidizing the glass during the annealing process may facilitate acicularization. For example, a low-silica glass can have a steep viscosity versus temperature curve that permits crystal growth in a preferred direction. Orienting the acicular phase can result in a glass-ceramic with substantial mechanical or electrical anisotropy, which may be desirable depending on the application.
[0017] The glass-ceramic may include a third crystalline phase. The third phase may be up to 20 volume percent of the glass-ceramic and is preferably at least about 10 volume percent. Advantageously, the third crystalline phase increases acicularity of the second phase. Without intending to be bound by this explanation, a third phase may improve acicularity for two reasons. First, glass-ceramics including above about 90% cordierite tend to produce cordierite crystals with aspect ratios less than 2:1. The blocky, short grain boundary, cordierite grains physically restrict elongated growth of the second phase. Second, high cordierite glasses include a substantial amount of alumina. High-alumina glasses do not allow solubility of as much titania as do glasses lower in alumina. Therefore, less acicular titanate can form. Also, premature phase separation and opalization can occur, so that benefits of the second phase are impaired. Inclusion of the third phase increases the aspect ratio of cordierite crystals and hinders phase separation of titanates.
[0018] The third phase comprises crystalline, ceramic compounds that permit acicular growth of the second phase. Preferably, the third phase has the capacity for lamellar twinning. Such ceramics twin by slipping along parallel twin planes. Twinning dissipates energy and can increase fracture toughness. The glass-ceramic may comprise up to 20% by volume of the third crystalline phase. Twinning ceramics include plagioclase feldspars, such as anorthite, Sr-feldspar, Ba-feldspar and pyroxenes such as enstatite, and aluminous enstatite,. Depending on the application, the feldspar should have little or no sodium compounds. Sodium-containing feldspars can harm dielectric properties, microwave transparency, and slow crystallization during annealing thereby causing higher residual glass.
[0019] It is contemplated that the third phase may also include, in addition to, or as an alternative to, the lamellar twinning phase, a crystalline phase selected from the group consisting of forsterite, fluormica, fluoramphibole, norbergite, spinel, sapphirine, mullite and xonotlite. These crystals phases can be included as means to enhance the toughness of the overall glass-ceramic. In particular, the following toughness enhancement mechanisms are contemplated/theorized: (1) the forsterite, fluoramphibole, norbergite, mullite and xonotlite phases enhance toughness due the presence of blade-like crystals; (2) the spinel and sappharine crystal phases enhance toughness due the high modulus of the crystal phase which is effective to deflect fractures; and (3) the fluormica crystal phase typically exhibits good cleavage which in turn enhances the toughness of the glass-ceramic.
[0020] The glass-ceramic may be made from a composition comprising, in weight percent, 35-50% SiO 2 , 10-35% Al 2 O 3 , 10-25% MgO, 7-20% TiO 2 , up to 5% CaO, and up to 10% SrO, and up to 5% F, where the sum of CaO and SrO is at least 0.5%. The composition is made into a glass and formed into a desired shape. Conveniently, additives may be added to facilitate processing so that the composition includes up to 5 wt. % BaO, MnO, FeO, CoO, ZnO, As 2 O 3 , Sb 2 O 3 , B 2 O 3 , Na 2 O, and K 2 O). The formed shape is annealed from 1100-1300° C. for a sufficient time to achieve the desired crystallinity. A typical annealing time is around 10 hours. Crystallinity usually exceeds 85%. Annealing produces a glass-ceramic comprising a discontinuous glass phase and a plurality of ceramic phases, including cordierite, a titanate, and optionally a twinning ceramic. The glass-ceramic can have a modulus of rupture of 40,000 psi, which is more than 50% greater than standard cordierite glass-ceramics. The glass-ceramic also has a CTE of less than 35×10 −7 /° C. and a fracture toughness up to about 6.0 MPa·m 0.5 .
[0021] The glass-ceramic of the present invention may be formed into any number of articles. The glass-ceramic is especially adapted to articles requiring low CTE, good fracture toughness, or oxidation resistance. One such article is a radome. The inherent oxidation-resistance of cordierite glass-ceramic permits its use where silicon nitride would oxidize. Further, cordierite glass-ceramics have typical densities from 2.63-2.77 g/ml compared to a silicon nitride density of about 3.30 g/ml. Articles consisting essentially of the toughened cordierite glass-ceramic will have lower mass than the same silicon nitride articles.
EXAMPLE 1
[0022] A mixture was made consisting essentially of 45 wt. % silica, 28 wt. % alumina, 14 wt. % magnesia, 2 wt. % calicia and 10 wt. % titania. The mixture was heated to form a clear, amber-colored glass and cast into a shape. The shape was first annealed for 2 hours at 800° C. The shape was fuirther annealed for 10 hours at 1200° C. until a crystallinity of 95 vol. % was achieved. The resultant glass-ceramic had a CTE of 30×10 −7 /° C. and a fracture toughness of 3.8 MPa·m 0.5 . Prior art cordierite glass-ceramic have a CTE of 55×10 −7 /° C. and a fracture toughness of 2.2 MPa·m 0.5 . The cordierite glass-ceramic of the present invention had a nearly 50% reduction in CTE while improving fracture toughness by over 70%.
[0023] The following Table 1 gives further examples of representative compositions according to the invention. Compositional information is in weight percent and is, as batched, unless otherwise indicated.
[0000]
TABLE 1
A
B
C
D
E*
F
G
H*
I
J
K
SiO 2
42.6
43.9
45.4
46.7
45.0
43.5
42.7
44.5
44.3
43.6
45.4
Al 2 O 3
21.4
20.7
21.1
25.0
28.3
31.7
29.9
28.9
25.7
25.0
18.9
MgO
18.8
22.8
17.9
16.5
14.1
12.1
12.2
14.5
15.0
16.5
21.7
CaO
0.0
1.2
3.9
1.8
2.0
3.0
0.0
2.0
2.0
2.0
2.0
SrO
8.0
1.7
0.0
0.0
0.0
0.0
5.5
0.0
0.0
0.0
0.0
F
4.0
3.1
1.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
TiO 2
7.4
7.8
9.8
9.7
9.6
9.7
9.7
9.5
13.0
12.9
12.0
Na 2 O
1.1
heat treatment: ° C. - hours
950-4
800-2
1100-4
1100-10
1200-10
1175-10
1200-10
CTE (25-1000° C. × 10 −7 )
30.1
27.1
30.0
Knoop
855
852
Toughness MPa · m 0.5
2.5
3.8
2.8
Density
2.764
2.63
*Composition, as analyzed
[0024] Obviously, numerous modifications and variations of the present invention are possible. It is, therefore, to be understood that within the scope of the following claims, the invention may be practiced otherwise than as specifically described. While this invention has been described with respect to certain preferred embodiments, different variations, modifications, and additions to the invention will become evident to persons of ordinary skill in the art. All such modifications, variations, and additions are intended to be encompassed within the scope of this patent, which is limited only by the claims appended hereto. | An internally nucleated, toughened cordierite glass-ceramic is disclosed. The cordierite glass-ceramic has good oxidation resistance and fracture toughness and coefficient of thermal expansion rivaling that of silicon nitride. The glass-ceramic may be cast as a liquid. Annealing produces a material of high crystallinity combining high hardness, high Young's modulus, good thermal stability, high strength, low density and good dielectric properties. The glass-ceramic comprises interlocking crystalline phases dominated by cordierite and a second phase having an elongated or acicular structure. A third phase may comprise a crystalline ceramic that promotes acicularity of the second phase. The third phase is preferably capable of twinning. | 2 |
RELATED APPLICATION
This application is a continuation-in-part of our prior copending Provisional application Ser. No. 60/042,434, filed Mar. 28, 1997, and entitled: SINGLE SCREW SLIDE SCREW TUNER.
BACKGROUND OF INVENTION
The efficient transmission of generated radio frequency (RF) power to a suitable antenna has been an ongoing problem for years. Cable mismatch and resistance over long runs of several feet or more, adapter and connector mismatch, etc. result in significant loss of power to the antenna. A properly designed tuner placed between the problem mismatch and the antenna is known to result in significantly more power reaching the antenna. There are several coaxial designs existing today which solve this problem in varying degrees. One of these deigns is the Maury Microwave Corp.'s model 1643C (See page 139 of that company's 1996/1997 catalog). This coaxial device, as do others, makes use of two micrometer driven tuning stubs housed in one sliding carriage. Each tuning stub has a flat end movable toward or away from the central conductor of the coaxial cable to vary the capacity of the tuner. The two stubs are mounted on a carriage. The carriage is moved along the length of the transmission line to vary the phase of the tuner. The capacities of the stubs plus said phase shift provide the necessary impedance change to tune out power reflecting impedance change to tune out power reflecting mismatches. This principle is more thoroughly discussed on pages 60 to 65 of the book Microwave Impedance Measurement by P. I. Somlo and J. D. Hunter published by Peter Peregrinus Ltd., London (1985). Copies of said pages 60-65 and of said page 139 are included in the Information Disclosure Statement filed with this application for patent.
Thus, prior art slide screw tuners generally require a manipulation of two stubs and a carriage to achieve optimum results. To get good results is very time consuming even to the point of frustration. In addition most prior art tuners have a very limited tolerance for average and peak power handling. As shown in said book, 50 watts is a good indication of what is currently available.
SUMMARY OF INVENTION
In the prior art the amount of capacity between the stub-end and a central conductor is limited by (1) sparkover if the stub-end is too close to the central conductor, and (2) the diameter of the central conductor. In view of these limitations, a single stub is inadequate.
With our invention, a single stub is adequate as we use a curved capacitor electrode that is not only smooth (free of sharp points or edges) but has a stub-end that is concentric, or at least very roughly concentric, with the central conductor in at least one location of the micrometer screw. This increases the maximum capacity of a single stub. A further increase in capacity may be obtained by extending the concentric stub-end longitudinally along the central conductor.
Since only one stub is required, tuning is greatly simplified. Only two parameters need to be adjusted for optimum results. These two parameters are (1) the proximity of the single stub and the central conductor and (2) the position of that stub along the coaxial conductor.
As explained above, existing tuners can often be difficult to use, are time consuming and are limited in their power handling capacity. The result is that the user of the prior art tuners spends more money, than necessary, providing more power amplification instead of optimizing existing transmission of available power through tuning.
In our invention, we use only one tuning stub that requires no interaction with a second stub and we have increased the peak power capacity to 1 kW. This makes our tuner usable on many pulse radar systems and offers the user not only quicker tuning but also alternative applications that use coaxial configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of our new tuner
FIG. 2 is an end cross-sectional view taken along line 2--2 of FIG. 1.
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 5.
FIG. 4 is a cross-sectional of a limited portion of the tuner of FIGS. 1 to 3 and shows the capacitor element 20 and the central conductor 23.
FIG. 5 is a top view of the tuner of FIG. 1.
DETAILED DESCRIPTION
FIG. 1 shows an overall view of our invention, a single stub sliding tuner. It has two type "N" coaxial connectors (in accordance with MIL-C-39012), each of opposite sex, one male one female. As seen in FIG. 2, a central conductor 23 is supported at each end by the connectors and along the entire length of the body by a Teflon insulator 21. The body 17 has a square cross-section (FIG. 2), with appropriate machining to support a movable carriage 14 and the micrometer adjustment stem 11. As discussed earlier, interaction of the carriage 14 and the micrometer adjustment stem 11, when introduced to a coaxial transmission line provides a tuning phenomenon producing a greater efficiency of transmitted power.
FIG. 2 shows a cross section taken at 2--2 of FIG. 1. The micrometer body 25 is carried by the carriage 14. When the knurled adjusted knob 10 is rotated the stem 11 moves up and down. The spring 24 is in compression between the plunger 12 and the bushing 13. The spring pressure maintains a consistent interface between the rotating micrometer stem 11 and the nonrotating plunger 12. Since the foot 20 is threaded to the plunger 12 adjustment of the micrometer knob 10 causes movement of the foot 20 closer to or away from the central conductor 23. The proximity of the foot 20 to the central conductor 23 creates a variable capacitance between the foot 20 and central conductor 23. Note that the bottom of the foot 20 is concave and relatively concentric with the central conductor 23 allowing a closer proximity to and a greater capacitance with the central conductor 23. The shoulder on the plunger 12 at point A in FIGS. 2 and 3 provides a stop when contact is made with the bushing 13. This eliminates over insertion of the foot 20 and possible damage to the central conductor 23. The opening or slot 27 in the Teflon insulator 21 is only a few thousandths of an inch larger than the width of the foot 20 providing a guide during movement. Since the foot 20 is almost as wide as slot 27, the walls of slot 27 prevent rotation of foot 20 and guide that foot. The slot 27 in the insulator 21 is conversely smaller than the slot 28 in the body 17 eliminating the possibility of any contact at that interface. Locking screw 26 provides a lock that eliminates further movement of the foot 20 after optimum tuning has been achieved. It is very important to note that during any movement of the plunger 12 and foot 20 that they are maintained at the same ground potential as the carriage 14 by the resilient metallic star 18. The star 18 is compressed between the bushing 13 and the carriage 14. It is also important to note the contact between the metal carriage 14 and the metal top plate 15 and the metal body 17 are all at the same ground potential through the contact made by the metal sleeve 19 (See FIGS. 2, 3, and 4). The top plate 15 is fastened to the body 17 by screws 29 as shown in FIG. 5 (top view) and provides a smaller slot width to minimize any RF radiation that may occur during use.
Our invention allows for tuning of very high voltage transmission lines up to and including 1 KW. This is accomplished through the contour of the metallic foot 20. It has no sharp corners reducing the potential for areas of high current density and flash over. It is concave and concentric with the central conductor 23 increasing capacitance at a greater distance from the central conductor 23. The central conductor 23 is encased in an insulating material of polyolefin 22. These two features are unique and vertually eliminate flash over making it very useful in radar and other high voltage tuning applications. The surface of foot 20 that faces the central conductor 23 is a capacitor element.
The central conductor 23 diameter is slightly oversized with respect to the diameter of the hole in the body 17 to maintain a good 50 ohms impedance. The dielectric constant of the Teflon insulator 21, renders the body 17 slightly capacitive. This compensates for the slot in the body 17 which is slightly inductive. The combination of the two X C and X L combine to give nearly a 50 ohm impedance and a good match.
FIGS. 2 and 3 show the nylon slider 16 attached to the carriage 14 and inset in the machined channels 31 of the body 17. This allows for a smooth movement of the carriage 14 and foot 20 along nearly the entire length of the body 17 and central conductor 23. This movement along the length of the central conductor 23 will vary the phase of the tuner, allowing tuning regardless of wavelength or frequency. When it is desired to adjust the tuner by moving the carriage 14 along the length of the tuner, the carriage 14 is moved manually to thus slide the slider 16 (which is a projection integral with body 14) along the longitudinal slot 31 (which runs the full length of the tuner).
This invention is quite different than the prior art in that it minimizes tuning time by the use of only one tuning foot 20 which is longer than the diameter of the stem 11 but not longer than 1/8 wavelength eliminating the need for two stubs. The invention provides a greater range of capacitance due to the contour of the tuning foot 20 and the increased proximity of the foot 20 to the central conductor 23, readily tuning VSWR's to 2:1 resulting in reflected power of less than 1% in significantly less time than prior art with dual stubs. The invention provides for the transmission of higher power (to include 1 KW average and 3 KW peak power) since the spark-over voltage is higher.
Unlike the two-stub screw tuners, the capacitor element on foot 20 cannot rotate during tuning or movement of the carriage 14. Further unlike the two-stub tuners, the capacitor element on foot 20 is longer than the diameter of the stem 11 of the tuner; thus greatly increasing the available capacity. | A tuner for radio frequency coaxial cable transmission lines is provided. It requires only one micrometer adjusting screw since the capacitor electrode that mates with the central conductor of the coaxial line is not only curved to give a large area in proximity to the central conductor but is rectangular and much longer than the diameter of the micrometer screw. | 7 |
FIELD OF THE INVENTION
The present invention relates generally to a product container, and, more particularly, to a compartmented tray-type container for transporting multiple products.
BACKGROUND OF THE INVENTION
Multiple product containers are used to transport several products at a time. For example, a multiple product container may be used at stadium events to transport snacks and beverages, or may be used to deliver pizza orders. Some such containers consist of a paper tray with an opening for holding a beverage cup and a space for the food items. While such trays are simple and economical, they allow heat transfer from the hot food items to the cold beverage which is undesirable. Other containers are in the form of a box structure typically constructed of corrugated paperboard or heavy gauge paper stock, and come to the food server assembled thereby requiring vast amounts of storage space. Therefore, it will be appreciated that it would be highly desirable to have a multiple product container that is constructed of thin stock, that comes to the food server in a flat condition requiring minimum storage space, and that may be used to both transport and serve multiple products.
SUMMARY OF THE INVENTION
The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to the present invention, a multiple product container has a partition dividing the container into a food compartment and a beverage compartment for a beverage permitting hot food and cold beverages to be transported in a single container. The beverage compartment is a tube having an opening for holding a beverage container in an upright position. The bottom wall of the food compartment is reinforced. The multiple product compartmented tray is formed from a blank and arrives to the food server partially assembled but collapsed flat. The food server erects the collapsed portion of the container and inserts the beverage containers in the tubular compartment formed. A pull tab and tear strip facilitate easy access to the beverage containers in the tubular beverage compartment.
These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of a set-up compartmented tray according to the present invention.
FIG. 2 is a plan view of a blank from which the compartmented tray of FIG. 1 is formed.
FIG. 3 illustrates the blank of FIG. 2 partially assembled.
FIG. 4 illustrates further assembly of the blank of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-4, a compartmented tray 10 contains a food compartment 12 for transporting food 14 and a tubular beverage compartment 16 for transporting a stored beverage container 18. The tubular compartment 16 contains an opening 20 through which an article such as a stored beverage container 18 is removed and subsequently held upright. The tray 10 is formed from a blank 22 of material containing a number of individual panels and containing fold lines along which the panels are folded to assemble the container. The outside of the tray 10 (shown face down in the blank 22 of FIG. 2) may be printed, decorated or covered with decorative foil or paper for aesthetic appeal.
Referring to FIG. 2, the blank 22 contains a bottom panel 24 having horizontally extending front and rear edges 26, 28 and first and second opposed side edges 30, 32 extending vertically between the front and rear edges 26, 28. A plurality of receiving slots 34 are formed in the bottom panel 24 along the front edge 26, and another plurality of receiving slots 36 are formed in the bottom panel 24 along the first side edge 30. Each receiving slot 34, 36 is elongated.
A first sidewall panel 38 has an outer wall panel 40 attached along a first vertical fold line 42 at a bottom edge of the outer wall panel 40 to the first side edge 30 of the bottom panel 24. The first sidewall panel 38 has an inner wall panel 44 with tabs 46 along its bottom edge with a top edge joined along a second vertical fold line 48 to a top edge of the outer wall panel 40. Each tab 46 is preferably a straight rectangular protrusion with its long side parallel to first side edge 42 and its short side perpendicular to side edge 42. Each tab 46 fits into an associated slot 36 when the blank 22 is assembled into tray 10. The slot protrusion permits a slot to deform slightly to accept a tab and then grip the tab as the slot reforms. The inner and outer wall panels 44, 40 define a front slot 50 and a rear slot 52 along the second fold line 48. In blank 22 slots 50 and 52 appear circular, but when panels 40 and 44 are folded along fold line 48 placing panels 40 and 44 in face to face relation, U-shaped slots are formed.
A second sidewall panel 54 has an outer wall panel 56 attached along a third vertical fold line 58 at a bottom edge of the outer wall panel 56 to the second side edge 32 of the bottom panel 24. A top wall panel 60 is attached along a fourth vertical fold line 62 at a first side edge of the top wall panel 60 to a top edge of the outer wall panel 56. The top wall panel 60 defines front and rear receiving slots 64, 66 and a central opening 68 adjacent a second side edge and defines two rows of perforations extending vertically from the opening 68 forming a tear strip 69 with a pull tab 70. Receiving slots, 64, 66 are preferably square extending to fold line 62 so that fold line 62 is contiguous with one side of each square. Slot 64 is located on one side of central opening 68 and slot 66 is located on the other side of opening 68. Central opening 68 has an arcuate segment running with and spaced from vertical fold line 62. One end of the arcuate segment is joined to a straight segment extending to the second side edge of top wall panel 60. The other end of the arcuate segment is joined to a corner of the tab of pull tab 70 which is joined to a straight segment extending to the second side edge of top wall panel 60. When the pull tab 70 is grasped and lifted with a thumb and index finger, the tear strip 69 separates along the two rows of perforations creating a slot that effectively enlarges central opening 68.
An inner wall panel 72 is attached along a fifth vertical fold line 74 at a top edge of the inner wall panel 72 to a second side edge of the top wall panel 60 with inner wall panel 72 defining an opening 76 adjacent the top edge that merges with opening 68 in the top wall panel 60. Opening 76 is preferably a semicircle with its ends joined to straight segments extending to the top edge of inner wall panel 72. Openings 68 and 76 merge at fold line 74 to form central opening 20 through which the stored beverage container 18 is retrieved. A glue flap 78 is attached along a sixth vertical fold line 80 at a bottom edge of the inner wall panel 72. During partial assembly the glue flap 78 is fastened to the bottom panel 24.
A front sidewall panel 82 has an outer wall panel 84 attached along a seventh horizontal fold line 86 at a bottom edge of the outer wall panel 84 to the front edge 26 of the bottom panel 24. An inner wall panel 88 has a series of tabs 90 along its bottom edge and has its top edge joined along an eighth horizontal fold line 92 to a top edge of the outer wall panel 84. Each tab 90 is preferably a straight rectangular protrusion with its long sides parallel to front edge 26 and its short sides perpendicular to front edge 26. Each tab 90 fits into a slot 34 during container assembly by slightly deforming slot 34 to accept tab 90.
A first end panel 94 with a first locking tab 96 is attached to one end of outer wall panel 84 along a ninth vertical fold line 98 and a second end panel 100 with a second locking tab 102 is attached to the other end of outer wall panel 84 along a tenth vertical fold line 104. The locking tab 96 is a rectangular protrusion with one side of the rectangle being an extension of the vertical end of end panel 94 that is distant from fold line 98, and another parallel side extending outward from end panel 94 in a direction perpendicular to horizontal fold line 92. The inside corner at the intersection of tab 96 and end panel 94 is preferably radiussed to prevent tearing and facilitate insertion into front slot 50. End panels 94 and 100 may each have a diagonal fold line along which each panel is resiliently folded to facilitate insertion into an appropriate slot during container assembly. Tab 102 is a mirror image of tab 96 and fits in front receiving slot 64 when the container is assembled.
Still referring to FIG. 2, a rear sidewall panel 106 is attached along an eleventh horizontal fold line 110 at a bottom edge of rear panel 106 to the rear edge 28 of the bottom panel 24. A first end panel 112 with a first locking tab 114 is attached to one end of rear panel 106 along a twelfth vertical fold line 116 and a second end panel 118 with a second locking tab 120 is attached to the other end of rear panel 106 along a thirteenth vertical fold line 122. Tab 114 mates with rear opening 52 and is a mirror image of tab 96. Similarly, tab 120 mates with rear opening 66 and is a mirror image of tab 114. A top panel 124 is attached along a fourteenth horizontal fold line 126 at a bottom edge of the top panel 124 to a top edge of the rear panel 106.
A tapered flap 128 is attached along a fifteenth horizontal fold line 130 at a bottom edge of the flap 128 to a top edge of the top panel 124. Preferably, a lip 132 extends from the top 124 forming an indentation in the flap 128. When the container is assembled, the lip 132 rests on top of the front sidewall to facilitate raising a closed top 124 which rests on the front sidewall and top wall panel 60 of the second sidewall panel 54. Lip 132 also helps prevent the top 124 from dropping into the interior of the assembled container.
Assembly of the tray 10 from the blank 22 begins by applying glue to the bottom panel 24, as indicated by the stippling in FIG. 2, to form the tubular compartment. The top panel 60 is folded over onto sidewall panel 56 by folding along fold line 62 to bring the glue flap 78 into contact with the glue applied to the bottom panel. This preassembly is preferably performed at the factory, but a self-stick adhesive can be applied to glue flap 78 and the complete assembly performed by the food server as needed.
FIG. 3 illustrates partial assembly of the blank wherein the blank is still flattened for shipping to the food server. In the preferred embodiment illustrated, the tubular compartment is collapsible about lines where the walls 56, 72 adjoin the bottom wall panel 24. FIG. 4 illustrates partial assembly wherein the blank is set up by lifting up top panel 60 or inner wall panel 72 by folding along fold lines 74 and 80, respectively, forming the outer sidewall and inner sidewall of the container. The glue flap 78, in addition to anchoring the outer and inner walls, serves as a stiffening rib for the bottom of the container. Additional stiffening of the bottom is achieved by adding ribs or an embossment on the bottom side of the bottom as shown by the dashed lines 25 in FIG. 2.
Assembly continues by folding front inner panel 88 along fold lines 92 onto front outer panel 84 thereby forming the front sidewalls of the container. Tabs 90 are inserted into the slots 34 when panels 88 and 84 are folded onto one another End flaps 94 and 100 are folded upward perpendicular to the front sidewall. The front sidewall is then folded along the fold line 86 as the left end panel 100 is guided into the front open end of the second compartment 16 formed by the bottom wall, inner and outer second outer and intermediate sidewalls and the top wall, that is bottom wall 24, second outer sidewall 72, intermediate sidewall 56, and top wall 60. The upstanding tab 102 is guided into the front opening 64 to lock the front panel in an upright position.
At the rear of the container, the rear wall 106 is folded along the folder line 110 to an upright position and the top 124 is folded along fold line 126 so that it overlies the bottom panel 24. End panels 112 and 118 are then folded along fold lines 116 and 122, respectively. End panel 118 is then inserted into the rear end of the second compartment 16 and the locking tab 120 is guided into the rear receiving opening 66. On the right side of the container, outer sidewall flap panel 40 is folded upward along fold line 42, end panels 94 and 112 are brought into contact with the inside of outer sidewall panel 40 while inner sidewall panel 44 is folded along fold line 48 to enclose the end flaps 94, 112. As panel 44 is folded over outer panel 40, the locking tabs 96, 114 are guided into their respective receiving openings 50, 52.
Tabs 46 are inserted into slots 36 as the inner panel 44 is folded over onto the outer panel 40 and end panels 94, 112. Flap 128 is now folded along fold line 130 exposing lip 132 which completes assembly of the container except for closing the container after the food items are inserted. At this stage of the assembly, the beverage containers are preferably inserted into the second compartment 16. The food items are now inserted or placed in the first compartment 12 on the bottom panel 24 of the box for shipping or delivers.
It can now be appreciated that there has been presented a compartmented tray which may be used as a multiple product shipping container. The container has a tray-like first compartment for transporting the food items and a tubular second compartment for transporting beverage containers. The cold beverage containers are separated from the hot food by the inner wall panel which isolates the hot food compartment from the cold beverage compartment. The double wall construction of the front side wall and the first sidewall help strengthen the container and insulates hot food items from the outside environment.
The multiple product container is very useful as a pizza and beverage container because it holds the hot pizza in the tray compartment away from a cold beverage in the tubular compartment. It is also very useful at stadium events because it provides a holder for an opened beverage container.
As is evident from the foregoing description, certain aspects of the invention are not limited to the particular details of the examples illustrated, and it is therefore contemplated that other modifications and applications will occur to those skilled in the art. For example, the container can be assembled from the blank using a different sequence of steps than described, and, while a unitary blank is preferred, a multi-piece blank can be used. Also, the vertical and horizontal fold lines can be scored with a series of alternating working scores and pre-break scores wherein adjoining panels may separate slightly when sharply folded at the pre-break scores. Also, the preferred embodiment illustrated and described above employs a combination of slots and tabs to erect the walls of the tray and compartments, however, other means used in the packaging arts, such as adhesion of panels to one another, may be used. It is also to be noted that the invention is useful as a tray without all of the side walls which surround the tray's perimeter. It is accordingly intended that the claims shall cover all such modifications and applications as do not depart from the true spirit and scope of the invention. | A multiple product container has at least one tubular compartment disposed adjacent a tray compartment. The tubular compartment has at least one aperture at its top-most portion for extraction of an elongated product and retention of the elongated product in an upright disposition. A tear strip further facilitates removal of the elongated product from the tubular compartment. | 8 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to home decorations and more particularly to physical supports for decorations such Christmas trees.
[0002] Christmas trees are a common type of holiday decoration. A natural or artificial tree is usually supported by a relatively small tripod-type base at its root end, and hung with decorations such as electric lights and glass or ceramic ornaments.
[0003] One problem with a Christmas tree is that it can be heavy and have a high center of gravity (“top-heavy”). A Christmas tree can easily be knocked over by a child or a pet. If a tree falls over it may it may damage or destroy ornaments having significant financial or sentimental value. It could also cause significant damage to the home or its furnishings or injury to occupants. Furthermore, in extreme cases, broken electric lights or spilled water could cause a fire or other structural damage.
BRIEF SUMMARY OF THE INVENTION
[0004] This problem is addressed by a support that can be placed around a tree or pole to increase its stability.
[0005] According to one aspect of the technology described herein, a support apparatus includes: an extension member with opposed first and second ends; a yoke disposed at the first end of the extension member; and a foot disposed at the second end of the extension member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The invention may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures, in which:
[0007] FIG. 1 is a schematic side view of a support;
[0008] FIG. 2 is an exploded view of the support shown in FIG. 1 ;
[0009] FIG. 3 is a partially-broken-away top plan view of a yoke of the support shown in FIG. 1 ;
[0010] FIG. 4 is a side elevation view of the yoke shown in FIG. 3 ;
[0011] FIG. 5 is a schematic side view showing the support of FIG. 1 being used to support a tree;
[0012] FIG. 6 is a schematic top plan view showing an array of the supports of FIG. 1 arranged about a tree trunk in a tripod pattern;
[0013] FIG. 7 is a schematic top plan view of an alternative support; and
[0014] FIG. 8 is a schematic perspective view of the support of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
[0015] Referring to the drawings wherein identical reference numerals denote the same elements throughout the various views, FIGS. 1 and 2 illustrate an exemplary support 10 . The basic components of the support 10 are an extension member 12 , a yoke 14 , and a foot 16 .
[0016] The extension member 12 is an elongated element with upper and lower ends 18 , 20 respectively. The extension member 12 may have a fixed or adjustable length. As used herein, the term “adjustable” refers to the length being selectively variable without having to be permanently changed, i.e. the length can be adjusted without permanently removing or adding material. Nonlimiting examples of adjustable structures include modular structures, sliding structures, and telescoping structures. In the illustrated example, the extension member 12 includes an upper tube 22 which telescopes inside a lower tube 24 . An internal detent mechanism or a twist-lock mechanism (not shown) is provided to fix the extension member 12 at any desired length. This type of telescoping device is sold commercially for use as an extension handle, e.g. for being attached to a paint roller or similar tool.
[0017] The upper end 18 of the extension member 12 includes some means for attachment to the yoke 14 , such as an interlocking surface, a fastener, or a latching mechanism. In the illustrated example, the upper end 18 has male threads 25 formed thereon.
[0018] Optionally, the extension member 12 may be decorated, for example by painting, powder coating, anodization, printing, or covering with material such as vinyl wrap. For example, the decoration may incorporate a holiday theme, or it may incorporate a color or pattern intended to camouflage the appearance of the support 10 .
[0019] Referring to FIGS. 3 and 4 , the yoke 14 is generally Y-shaped with a proximate end 26 and a distal end 28 . The yoke 14 includes a body 30 with a pair of spaced-apart fingers 32 extending therefrom, adjacent the distal end 28 . The fingers 32 may be generally parallel to each other. The spacing between the fingers 32 may be selected sufficient to receive a portion of a branch or trunk of a tree. By way of example and not of limitation, the spacing between the fingers 32 may be in a range of a fraction of an inch to several inches. The yoke 14 includes some means for attachment to the upper end 18 of the extension member 12 , such as an interlocking surface, a fastener, or a latching mechanism. In the illustrated example, the body 30 of the yoke 14 incorporates female threads 34 adjacent the proximate end 26 , which engage the male threads 25 of the extension member 12 .
[0020] The yoke 14 may be manufactured from any material providing adequate strength for the purpose of coupling to the extension member 12 and bearing against a tree. Non-limiting examples of suitable materials include polymers, metals, and wood. In the illustrated example the yoke 14 is an integral, unitary, or monolithic component molded from plastic such as polyethylene.
[0021] The foot 16 is configured to engage a floor or ground surface to prevent slippage of the support 10 . The foot 16 may incorporate one or more features to promote friction and/or traction, such as a soft or rough surface, or pins, ribs or spikes. In the illustrated example, the foot 16 is a cap made from a resilient material such as natural or synthetic rubber, sized to engage the lower end 20 of the extension member 12 in a friction fit.
[0022] Optionally, the yoke 14 and the foot 16 may be provided as a kit and used to assemble a support 10 using an existing telescoping extension member 12 as described above.
[0023] FIG. 5 shows how the support 10 may be used to brace a Christmas tree. A representative tree 36 includes a central trunk 38 supported by a base 40 which in turn rests on a floor 42 . A plurality of branches 44 extend outward from the trunk 38 . The yoke 14 receives the trunk 38 and/or a branch 44 to prevent the upper end 18 from disengaging. The foot 16 rests against or engages the floor 42 . The support 10 extends upward from the floor 42 at an acute angle. The support 10 thus directly braces the tree 36 from toppling in a direction towards the support 10 , and provides a wider effective base for the tree 36 . The angle and/or length of the support 10 may be selected to provide sufficient stability and resistance to toppling while minimizing the exposed portion of the support 10 .
[0024] As shown in FIG. 6 , a number of supports 10 may be arrayed around the trunk 38 as necessary to provide complete support to the tree 36 . Each support 10 braces the tree 36 against falling in a direction in line with the support 10 , but does not provide lateral support. If the tree 36 is freestanding, a minimum of three supports 10 arrayed at equal spacings (e.g. 120°) will brace the tree 36 against falling in any direction. If the tree 36 is already positioned such that it is protected against falling in one or more directions, for example if the tree 36 is placed in an interior corner of a room, then fewer supports 10 may be sufficient.
[0025] FIG. 7 illustrates an alternative yoke 114 similar in construction to the yoke 14 described above. The yoke 114 is interchangeable in the assembly of the support 10 with the yoke 14 described above. Elements of the yoke 14 not specifically described may be considered identical to the yoke 14 . The yoke 114 is generally Y-shaped with a body 130 with a pair of spaced-apart fingers 132 extending therefrom. The yoke 114 includes some means for attachment to the upper end 18 of the extension member 12 , as described above. A pair of ribs 134 are disposed on opposite sides of the body 130 . Each rib 134 as a slot 136 formed therethrough.
[0026] FIG. 8 illustrates the yoke 114 with an adjustable strap 138 threaded through the slots 136 . The strap 138 is adjustable in length and may be secured with a fastening mechanism such as the illustrated buckle 140 and hook-and-loop fastener 142 . When the buckle 140 and hook-and-loop fastener 142 are released the strap 138 defines an open shape with two free ends that may be wrapped around a tree or pole. When the buckle 140 and hook-and-loop fastener 142 are secured, the free ends are fastened together and the strap 138 defines a closed loop in cooperation with the yoke 114 . In use with the support 10 , the strap 138 may be used to secure the yoke 114 to the pole, trunk, or branch to ensure that the support 10 does not slip out of position.
[0027] While the support 10 has been described in the context of supporting a Christmas tree, the principles described herein may be adapted to other uses. In particular, the support 10 to be used to support any upstanding structure such as a pole, rod, or bar.
[0028] Furthermore, the support 10 or 110 may also be used as a tool, with the yoke 14 or 114 serving a hook or gripper (optionally using the strap 138 for security) and the extension 12 serving as a long handle. Used this way, the support 10 or 110 can be used to hold objects such as lights, ornaments, etc. These items can be lifted up and installed on, or removed from, the tree 36 or other locations at elevations above the user's natural reach.
[0029] The foregoing has described a tree and pole support. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.
[0030] Each feature disclosed in this specification (including any accompanying claims, abstracts and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
[0031] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstracts and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. | A support apparatus includes: an extension member with opposed first and second ends; a yoke disposed at the first end of the extension member; and a foot disposed at the second end of the extension member. | 4 |
TECHNICAL FIELD OF INVENTION
[0001] The present invention relates to inhibitors of p38, a mammalian protein kinase involved in cell proliferation, cell death and response to extracellular stimuli. The invention also relates to methods for producing these inhibitors. The invention also provides pharmaceutical compositions comprising the inhibitors of the invention and methods of utilizing those compositions in the treatment and prevention of various disorders.
BACKGROUND OF THE INVENTION
[0002] Protein kinases are involved in various cellular responses to extracellular signals. Recently, a family of mitogen-activated protein kinases (MAPK) has been discovered. Members of this family are Ser/Thr kinases that activate their substrates by phosphorylation [B. Stein et al., Ann. Rep. Med. Chem., 31, pp. 289-98 (1996)]. MAPKs are themselves activated by a variety of signals including growth factors, cytokines, UV radiation, and stress-inducing agents.
[0003] One particularly interesting MAPK is p38. p38, also known as cytokine suppressive anti-inflammatory drug binding protein (CSBP) and RK, was isolated from murine pre-B cells that were transfected with the lipopolysaccharide (LPS) receptor, CD14, and induced with LPS. p38 has since been isolated and sequenced, as has the cDNA encoding it in humans and mouse. Activation of p38 has been observed in cells stimulated by stress, such as treatment of lipopolysaccharides (LPS), UV, anisomycin, or osmotic shock, and by cytokines, such as IL-1 and TNF.
[0004] Inhibition of p38 kinase leads to a blockade on the production of both IL-1 and TNF. IL-1 and TNF stimulate the production of other proinflammatory cytokines such as IL-6 and IL-8 and have been implicated in acute and chronic inflammatory diseases and in post-menopausal osteoporosis [R. B. Kimble et al., Endocrinol., 136, pp. 3054-61 (1995)].
[0005] Based upon this finding, it is believed that p38, along with other MAPKs, have a role in mediating cellular response to inflammatory stimuli, such as leukocyte accumulation, macrophage/monocyte activation, tissue resorption, fever, acute phase responses and neutrophilia. In addition, MAPKs, such as p38, have been implicated in cancer, thrombin-induced platelet aggregation, immunodeficiency disorders, autoimmune diseases, cell death, allergies, osteoporosis and neurodegenerative disorders. Inhibitors of p38 have also been implicated in the area of pain management through inhibition of prostaglandin endoperoxide synthase-2 induction. Other diseases associated with Il-1, IL-6, IL-8 or TNF overproduction are set forth in WO 96/21654.
[0006] Others have already begun trying to develop drugs that specifically inhibit MAPKs. For example, PCT publication WO 95/31451 describes pyrazole compounds that inhibit MAPKs, and, in particular, p38. However, the efficacy of these inhibitors in vivo is still being investigated.
[0007] Other p38 inhibitors have been produced, including those described in WO 98/27098, WO 99/00357, WO 99/10291, WO 99/58502, WO 99/64400, WO 00/17175 and WO 00/17204.
[0008] Accordingly, there is still a great need to develop other potent inhibitors of p38, including p38-specific inhibitors, that are useful in treating various conditions associated with p38 activation.
[0009] Another protein kinase that is involved in cellular responses to extracellular signals is ZAP70. When the T cell receptor (TCR) in T cells is triggered by binding an antigen, it in turn activates ZAP70. ZAP70 acts to couple the TCR to a number of essential signalling pathways that are required for T cell differentiation and proliferation.
[0010] Given ZAP70's role in T cell signalling, ZAP70 may have a role in T cell mediated diseases. Such diseases include, without limitation, transplantation, autoimmune disease, e.g., RA, systemic lupus erythematosus (SLE), psoriasis, Sjogren's Syndrome, thyroiditis, pulmonary fibrosis, bronchiolitis obliterans, hemolytic anemia and Wegener's granulomatosis, cancer, including leukemia and lymphoma, multiple sclerosis, graft versus host disease, and Kawasaki syndrome.
[0011] Accordingly, there is a great need to develop inhibitors of ZAP70 that are useful in treating various conditions associated with ZAP70 activation.
SUMMARY OF THE INVENTION
[0012] The present invention addresses this problem by providing compounds that demonstrate inhibition of p38 and/or ZAP70.
[0013] These compounds have the general formula:
[0000]
[0000] wherein each of Q 1 and Q 2 are independently selected from a phenyl or 5-6 membered aromatic heterocyclic ring system, or a 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring.
[0014] A heterocyclic ring system or a heterocyclic ring contains 1 to 4 heteroatoms, which are independently selected from N, O, S, SO and SO 2 .
[0015] The rings that make up Q 1 are substituted with 1 to 4 substituents, each of which is independently selected from halo; C 1 -C 3 alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′ or CONR′ 2 ; O—(C 1 -C 3 )-alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′ or CONR′ 2 ; NR′ 2 ; OCF 3 ; CF 3 ; NO 2 ; CO 2 R′; CONR′; SR′; S(O 2 )N(R′) 2 ; SCF 3 ; CN; N(R′)C(O)R 4 ; N(R′)C(O)OR 4 ; N(R′)C(O)C(O)R 4 ; N(R′)S(O 2 )R 4 ; N(R′)R 4 ; N(R 4 ) 2 ; OR 4 ; OC(O)R 4 ; OP(O) 3 H 2 ; or N═C—N(R′) 2 .
[0016] The rings that make up Q 2 are optionally substituted with up to 4 substituents, each of which is independently selected from halogen; C 1 -C 3 straight or branched alkyl optionally substituted with R′, NR′ 2 , OR′, CO 2 R′, S(O 2 )N(R′) 2 , N═C—N(R′) 2 , R 3 , O—P(O 3 )H 2 , or CONR′ 2 ; O—(C 1 -C 3 )-alkyl; O—(C 1 -C 3 )-alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′, S(O 2 )N(R′) 2 , N═CR′—N(R′) 2 , R 3 , O—P(O 3 )H 2 , or CONR′ 2 ; NR′ 2 ; OCF 3 ; CF 3 ; NO 2 ; CO 2 R′; CONR′ 2 ; R 3 ; OR 3 ; NR 3 2 ; SR 3 ; C(O)R 3 ; C(O)N(R′)R 3 ; C(O)OR 3 ; SR′; S(O 2 )N(R′) 2 ; SCF 3 ; N═CR′—N(R′) 2 ; OR 4 ; O—CO 2 R 4 ; N(R′) C(O)R 4 ; N(R′) C(O)OR; N(R′) C(O)C(O)R 4 ; N(R′) S(O 2 )R 4 ; N(R′)R 4 ; N(R 4 ) 2 ; OR 4 ; OC(O)R 4 ; OP(O) 3 H 2 ; K; or CN.
[0017] Each R′ is independently selected from hydrogen; (C 1 -C 3 )-alkyl; (C 2 -C 3 )-alkenyl or alkynyl; phenyl or phenyl substituted with 1 to 3 substituents independently selected from halo, methoxy, cyano, nitro, amino, hydroxy, methyl or ethyl; or a 5-6 membered heterocyclic ring system optionally substituted with 1 to 3 substituents independently selected from halo, methoxy, cyano, nitro, amino, hydroxy, methyl or ethyl.
[0018] Each R is independently selected from hydrogen, —R 2 , —N(R 2 ) 2 , —OR 2 , SR 2 , —C(O)—N(R 2 ) 2 , —S(O 2 )—N(R′) 2 , —C(O)—OR 2 or —C(O)R 2 wherein two adjacent R are optionally bound to one another and, together with each Y to which they are respectively bound, form a 4-8 membered carbocyclic or heterocyclic ring.
[0019] Each R 2 is independently selected from hydrogen; or (C 1 -C 3 )-alkyl or (C 1 -C 3 )-alkenyl, each optionally substituted with —N(R′) 2 , —OR′, SR′, —O—C(O)—N(R′) 2 , —C(O)—N(R′) 2 , —S (O 2 )—N(R′) 2 , —C(O)—OR′, —NSO 2 R 4 , —NSO 2 R 3 , —C(O)N(R′)(R 3 ), —NC(O)R 4 , —N(R′)(R 3 ), —N(R′)(R′), —C(O)R 3 , —C(O)N(R′)(R 4 ), —N(R′) 2 , —C(O)N═C(NH) 2 or R 3 .
[0020] Each R 3 is independently selected from 5-8 membered aromatic or non-aromatic carbocyclic or heterocyclic ring systems each optionally substituted with R′, R 4 , —C(O)R′, —C(O)R 4 , —C(O)OR 4 or —K; or an 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring each optionally substituted with R′, R 4 , —C(O)R′, —C(O)R 4 , —C(O)OR 4 or —K.
[0021] Each R 4 is independently selected from R′; (C 1 -C 7 )-straight or branched alkyl optionally substituted with R′, N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , SO 2 N(R′) 2 or SO 2 N(R 5 ) 2 ; or a 5-6 membered carbocyclic or heterocyclic ring system optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , SO 2 N(R′) 2 or SO 2 N(R′) 2 .
[0022] Each R 5 is independently selected from hydrogen, (C 1 -C 3 )-alkyl, or (C 1 -C 3 )-alkenyl; each optionally substituted with —N(R′) 2 , —OR′, SR′, —C(O)—N(R′) 2 , —S(O 2 )—N(R′) 2 , —C(O)—OR′, —N—S (O 2 ) (R′), —NSO 2 R 6 , —C(O)N(R′)(R 6 ), —NC(O)R′, —N(R′)(R 6 ), —C(O)R 6 , —C(O)N═C(NH) 2 or R 6 .
[0023] Each R 6 is independently selected from 5-8 membered aromatic or non-aromatic carbocyclic or heterocyclic ring systems each optionally substituted with R′, —C(O)R′ or —C(O)OR′; or an 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring each optionally substituted with R′, —C(O)R′ or C(O)OR′.
[0024] R 7 is selected from H, halogen, or a (C 1 -C 3 ) straight chain or branched alkyl.
[0025] Each Y is independently selected from N or C. If either Y is N, then R or U attached to Y is a lone pair of electrons.
[0026] Z is CH, N, C(OCH 3 ), C(CH 3 ), C(NH 2 ), C(OH) or C(F).
[0027] Each U is independently selected from R or J.
[0028] Each J is independently selected from a (C 1 -C 4 ) straight chain or branched alkyl derivative substituted with T.
[0029] Each T is independently selected from either O(V) or N(H)(V).
[0030] Each V is independently selected from C(O)N═C(R′) (N(R′) 2 ), wherein the two geminal R on the nitrogen are optionally bound to one another to form a 4-8 membered carbocyclic or heterocyclic ring.
[0031] When the two R components form a ring, it will obvious to those skilled in the art that a terminal hydrogen from each unfused R component will be lost. For example, if a ring structure is formed by binding those two R components together, one being —CH 3 and the other being —CH 2 —CH 3 , one terminal hydrogen on each R component (indicated in bold) will be lost. Therefore, the resulting portion of the ring structure will have the formula —CH 2 —CH 2 —CH 2 —.
[0032] Each K is independently selected from a (C 1 -C 4 ) straight chain or branched alkyl derivative substituted with D, or —OP(O)(OH) 2 .
[0033] Each D is independently selected from either enantiomer of
[0000]
[0034] Each M is independently selected from either O or NH.
[0035] Each G is independently selected from NH 2 , OH, or H.
[0036] Each R 8 is independently selected from H, OH, C(O)OH, (C 1 -C 7 )-straight or branched alkyl optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , or SO 2 N(R 5 ) 2 ; or a 5-6 membered carbocyclic, heterocyclic or heteroaryl ring system optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , or SO 2 N(R 5 ) 2 When G forms a ring with R 8 , it will be obvious to those skilled in the art that a terminal hydrogen from the unfused G and R 8 component will be lost. For example, if a ring structure is formed by binding the G and R 8 components together, one being —NH 2 and the other being —CH 2 —CH 2 —CH 2 —CH 3 , one terminal hydrogen on each R component (indicated in bold) will be lost. Therefore, the resulting portion of the ring structure will have the formula —NH—CH 2 —CH 2 —CH 2 —CH 2 —.
[0037] In another embodiment, the invention provides pharmaceutical compositions comprising the p38 and/or ZAP70 inhibitors of this invention. These compositions may be utilized in methods for treating or preventing a variety of p38-mediated disorders, such as cancer, inflammatory diseases, autoimmune diseases, destructive bone disorders, proliferative disorders, infectious diseases, viral diseases and neurodegenerative diseases or ZAP70-mediated disorders, including transplantation, autoimune disease, cancer, multiple sclerosis, graft versus host disease, and Kawasaki syndrome. These compositions are also useful in methods for preventing cell death and hyperplasia and therefore may be used to treat or prevent reperfusion/ischemia in stroke, heart attacks, and organ hypoxia. The compositions are also useful in methods for preventing thrombin-induced platelet aggregation. Each of these above-described methods is also part of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] These compounds have the general formula:
[0000]
[0000] wherein each of Q 1 and Q 2 are independently selected from a phenyl or 5-6 membered aromatic heterocyclic ring system, or a 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring.
[0039] The rings that make up Q 1 are substituted with 1 to 4 substituents, each of which is independently selected from halo; C 1 -C 3 alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′ or CONR′ 2 ; O—(C 1 -C 3 )-alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′ or CONR′ 2 ; NR′ 2 ; OCF 3 ; CF 3 ; NO 2 ; CO 2 R′; CONR′; SR′; S(O 2 )N(R′) 2 ; SCF 3 ; CN; N(R′)C(O)R 4 ; N(R′)C(O)OR 4 ; N(R′)C(O)C(O)R 4 ; N(R′)S(O 2 )R 4 ; N(R′)R 4 ; N(R 4 ) 2 ; OR 4 ; OC(O)R 4 ; OP(O) 3 H 2 ; or N═C—N(R′) 2 .
[0040] The rings that make UP Q 2 are optionally substituted with up to 4 substituents, each of which is independently selected from halogen; C 1 -C 3 straight or branched alkyl optionally substituted with R′, NR′ 2 , OR′, CO 2 R′, S(O 2 )N(R′) 2 , N═C—N(R′) 2 , R 3 , O—P(O 3 )H 2 , or CONR′ 2 ; O—(C 1 -C 3 )-alkyl; O—(C 1 -C 3 )-alkyl optionally substituted with NR′ 2 , OR′, CO 2 R′, S(O 2 )N(R′) 2 , N═CR′—N(R′) 2 , R 3 , OP(O 3 ) H 2 , or CONR′ 2 ; NR′ 2 ; OCF 3 ; CF 3 ; NO 2 ; CO 2 R′; CONR′ 2 ; R 3 ; OR 3 ; NR 3 2 ; SR 3 ; C(O); C(O)N(R′)R 3 ; C(O)OR 3 ; SR′; S(O 2 )N(R′) 2 ; SCF 3 ; N═CR′—N(R′) 2 ; OR 4 ; O—CO 2 R 4 ; N(R′) C(O)R 4 ; N(R′) C(O)OR 4 ; N(R′)C(O)C(O)R 4 ; N(R′)S(O 2 )R 4 ; N(R′)R 4 ; N(R 4 ) 2 ; OR 4 ; OC(O)R 4 ; OP(O) 3 H 2 ; K; or CN.
[0041] Each R′ is independently selected from hydrogen; (C 1 -C 3 )-alkyl; (C 2 -C 3 )-alkenyl or alkynyl; phenyl or phenyl substituted with 1 to 3 substituents independently selected from halo, methoxy, cyano, nitro, amino, hydroxy, methyl or ethyl; or a 5-6 membered heterocyclic ring system optionally substituted with 1 to 3 substituents independently selected from halo, methoxy, cyano, nitro, amino, hydroxy, methyl or ethyl.
[0042] Each R is independently selected from hydrogen, —R 2 , —N(R 2 ) 2 , —OR 2 , SR 2 , —C(O)—N(R 2 ) 2 , —S(O 2 )—N(R 2 ) 2 , —C(O)—OR 2 or —C(O)R 2 wherein two adjacent R are optionally bound to one another and, together with each Y to which they are respectively bound, form a 4-8 membered carbocyclic or heterocyclic ring.
[0043] Each R 2 is independently selected from hydrogen; or (C 1 -C 3 )-alkyl or (C 1 -C 3 )-alkenyl, each optionally substituted with —N(R′) 2 , —OR′, SR′, —O—C(O)—N(R 4 ) 2 , —C(O)—N(R′) 2 , —S(O 2 )—N(R′) 2 , —C(O)—OR′, —NSO 2 R 4 , —NSO 2 R 3 , —C(O)N(R′)(R 3 ), —NC(O)R 4 , —N(R′)(R 3 ), —N(R′)(R′), —C(O)R 3 , —C(O)N(R′)(R 4 ), —N(R 4 ) 2 , —C(O)N═C(NH) 2 or R 3 .
[0044] Each R 3 is independently selected from 5-8 membered aromatic or non-aromatic carbocyclic or heterocyclic ring systems each optionally substituted with R′, R 4 , —C(O)R′, —C(O)R 4 , —C(O)OR 4 or —K; or an 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring each optionally substituted with R′, R 4 , —C(O)R′, —C(O)R 4 , —C(O)OR 4 or —K.
[0045] Each R 4 is independently selected from R′; (C 1 -C 7 )-straight or branched alkyl optionally substituted with R′, N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , SO 2 N(R′) 2 or SO 2 N(R 5 ) 2 ; or a 5-6 membered carbocyclic or heterocyclic ring system optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , SO 2 N(R′) 2 or SO 2 N(R′) 2 .
[0046] Each R 5 is independently selected from hydrogen, (C 1 -C 3 )-alkyl, or (C 1 -C 3 )-alkenyl; each optionally substituted with —N(R′) 2 , —OR′, SR′, —C(O)—N(R′) 2 , —S(O 2 )—N(R′) 2 , —C(O)—OR′, —N—S (O 2 ) (R′), —NSO 2 R 6 , —C(O)N(R′)(R 6 ), —NC(O)R′, —N(R′)(R 6 ), —C(O)R 6 , —C(O)N═C(NH) 2 or R 6 .
[0047] Each R 6 is independently selected from 5-8 membered aromatic or non-aromatic carbocyclic or heterocyclic ring systems each optionally substituted with R′, —C(O)R′ or —C(O)OR′; or an 8-10 membered bicyclic ring system comprising aromatic carbocyclic rings, aromatic heterocyclic rings or a combination of an aromatic carbocyclic ring and an aromatic heterocyclic ring each optionally substituted with R′, —C(O)R′ or C(O)OR′.
[0048] R 7 is selected from H, halogen, or a (C 1 -C 3 ) straight chain or branched alkyl.
[0049] Each Y is independently selected from N or C.
[0050] If either Y is N, then R or U attached to Y is a lone pair of electrons.
[0051] Z is CH, N, C(OCH 3 ), C(CH 3 ), C(NH 2 ), C(OH) or C(F).
[0052] Each U is independently selected from R or J.
[0053] Each J is independently selected from a (C 1 -C 4 ) straight chain or branched alkyl derivative substituted with T.
[0054] Each T is independently selected from either O(V) or N(H)(V).
[0055] Each V is independently selected from C(O)N═C(R′)(N(R′) 2 ), wherein the two geminal R on the nitrogen are optionally bound to one another to form a 4-8 membered carbocyclic or heterocyclic ring.
[0056] When the two R components form a ring, it will obvious to those skilled in the art that a terminal hydrogen from each unfused R component will be lost. For example, if a ring structure is formed by binding those two R components together, one being —CH 3 and the other being —CH 2 —CH 3 , one terminal hydrogen on each R component (indicated in bold) will be lost. Therefore, the resulting portion of the ring structure will have the formula —CH 2 —CH 2 —CH 2 —.
[0057] Each K is independently selected from a (C 1 -C 4 ) straight chain or branched alkyl derivative substituted with D, or —OP(O)(OH) 2 .
[0058] Each D is independently selected from either enantiomer of
[0000]
[0059] Each M is independently selected from either O or NH.
[0060] Each G is independently selected from NH 2 , OH, or H.
[0061] Each R 8 is independently selected from H, OH, C(O)OH, (C 1 -C 7 )-straight or branched alkyl optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , or SO 2 N(R 5 ) 2 ; or a 5-6 membered carbocyclic, heterocyclic or heteroaryl ring system optionally substituted with N(R′) 2 , OR′, CO 2 R′, CON(R′) 2 , or SO 2 N(R 5 ) 2 . When G forms a ring with R 8 , it will be obvious to those skilled in the art that a terminal hydrogen from the unfused G and R 8 component will be lost. For example, if a ring structure is formed by binding the G and R 8 components together, one being —NH 2 and the other being —CH 2 —CH 2 —CH 2 —CH 3 , one terminal hydrogen on each R component (indicated in bold) will be lost. Therefore, the resulting portion of the ring structure will have the formula —NH—CH 2 —CH 2 —CH 2 —CH 2 —.
[0062] A heterocyclic ring system or a heterocyclic ring contains 1 to 4 heteroatoms, which are independently selected from N, O, and S. A substitutable nitrogen on an aromatic or non-aromatic heterocyclic ring may be optionally substituted. N or S may also exist in oxidized form such as NO, SO and SO 2 .
[0063] One having ordinary skill in the art will recognize that the maximum number of heteroatoms in a stable, chemically feasible heterocyclic ring, whether it is aromatic or non-aromatic, is determined by the size of the ring, degree of unsaturation, and valence of the heteroatoms. In general, a heterocyclic ring may have one to four heteroatoms so long as the heterocyclic ring is chemically feasible and stable.
[0064] The term “chemically stable arrangement” or “chemically feasible and stable” as used herein, refers to a compound structure that renders the compound sufficiently stable to allow manufacture and administration to a mammal by methods known in the art. Typically, such compounds are stable at a temperature of 40° C. or less, in the absence of moisture or other chemically reactive conditions, for at least a week.
[0065] According to a preferred embodiment, Q 1 is selected from phenyl or pyridyl containing 1 to 3 substituents, wherein at least one of said substituents is in the ortho position and said substituents are independently selected from chloro, fluoro, bromo, —CH 3 , —OCH 3 , —OH, —CF 3 , —OCF 3 , —O(CH 2 ) 2 CH 3 , NH 2 , 3,4-methylenedioxy, —N(CH 3 ) 2 , —NH—S(O) 2 -phenyl, —NH—C(O)O—CH 2 -4-pyridine, —NH—C(O)CH 2 -morpholine, —NH—C(O)CH 2 —N(CH 3 ) 2 , —NH—C(O)CH 2 -piperazine, —NH—C(O)CH 2 -pyrrolidine, —NH—C(O)C(O)-morpholine, —NH—C(O)C(O)-piperazine, —NH—C(O)C(O)-pyrrolidine, —O—C(O)CH 2 —N(CH 3 ) 2 , or —O— (CH 2 ) 2 —N(CH 3 ) 2 .
[0066] Even more preferred are phenyl or pyridyl containing at least 2 of the above-indicated substituents both being in the ortho position.
[0067] Some specific examples of preferred Q 1 are:
[0000]
[0068] Most preferably, Q 1 is selected from 2-fluoro-6-trifluoromethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 2-chloro-4-hydroxyphenyl, 2-chloro-4-aminophenyl, 2,6-dichloro-4-aminophenyl, 2,6-dichloro-3-aminophenyl, 2,6-dimethyl-4-hydroxyphenyl, 2-methoxy-3,5-dichloro-4-pyridyl, 2-chloro-4,5 methylenedioxy phenyl, or 2-chloro-4-(N-2-morpholino-acetamido)phenyl.
[0069] According to a preferred embodiment, Q 2 is phenyl, pyridyl or naphthyl containing 0 to 3 substituents, wherein each substituent is independently selected from chloro, fluoro, bromo, methyl, ethyl, isopropyl, —OCH 3 , —OH, —NH 2 , —CF 3 , —OCF 3 , —SCH 3 , —OCH 3 , —C(O)OH, —C(O)OCH 3 , —CH 2 NH 2 , —N(CH 3 ) 2 , —CH 2 -pyrrolidine and —CH 2 OH.
[0070] Some specific examples of preferred Q 2 are:
[0000]
[0000] unsubstituted 2-pyridyl or unsubstituted phenyl.
[0071] Most preferred are compounds wherein Q 2 is selected from phenyl, 2-isopropylphenyl, 3,4-dimethylphenyl, 2-ethylphenyl, 3-fluorophenyl, 2-methylphenyl, 3-chloro-4-fluorophenyl, 3-chlorophenyl, 2-carbomethoxylphenyl, 2-carboxyphenyl, 2-methyl-4-chlorophenyl, 2-bromophenyl, 2-pyridyl, 2-methylenehydroxyphenyl, 4-fluorophenyl, 2-methyl-4-fluorophenyl, 2-chloro-4-fluorophenyl, 2,4-difluorophenyl, 2-hydroxy-4-fluorophenyl, 2-methylenehydroxy-4-fluorophenyl, 1-naphthyl, 3-chloro-2-methylenehydroxy, 3-chloro-2-methyl, or 4-fluoro-2-methyl.
[0072] According to another preferred embodiment, R 7 is a halogen. In a more preferred embodiment, R 7 is Cl.
[0073] According to another preferred embodiment, each Y is C.
[0074] According an even more preferred embodiment, each Y is C and the R and U attached to each Y component is hydrogen.
[0075] Some specific examples of preferred J are:
[0000]
[0076] According to another preferred embodiment, K is a 0-4 atom chain terminating in an ester.
[0077] According to another preferred embodiment, M is O.
[0078] Some specific examples of preferred K are:
[0000]
[0079] More preferably, K is selected from:
[0000]
[0080] Some preferred embodiments are provided in Tables 1 to 3 below:
[0000]
TABLE 1
Cmpd
Nmbr
Structure
101
102
103
104
105
106
107
108
109
110
[0000]
TABLE 2
Cmpd Nmbr
Structure
111
112
113
114
115
116
117
[0000]
TABLE 3
Cmpd
Nmbr
Structure
118
119
120
121
122
123
124
125
[0081] Particularly preferred embodiments include:
[0000]
[0000] wherein Ar is
[0000]
[0082] Particularly preferred embodiments also include:
[0000]
[0000] wherein Ar is
[0000]
[0083] Other particularly preferred embodiments include:
[0000]
[0000] wherein Ar is
[0000]
[0084] Other particularly preferred embodiments include:
[0000]
[0085] Other particularly preferred embodiments include:
[0000]
[0086] Other particularly preferred embodiments include:
[0000]
[0000] wherein X is N(CH 3 ) 2 ,
[0000]
[0087] Other particularly preferred embodiments include:
[0000]
[0000] wherein Y=Me or H; and X═(CH 2 ) 3 , CH 2 C(CH 3 ) 2 CH 2 , CH 2 N (Me) C(O)CH 2 .
[0088] Some most preferred embodiments include:
[0000]
[0089] According to another embodiment, the present invention provides methods of producing the above-identified compounds of the formulae (Ia), (Ib), (Ic) or (Id). Representative synthesis schemes are depicted below. In all schemes, the L1 and L2 groups on the initial materials are meant to represent leaving groups ortho to the nitrogen atom in a heterocyclic ring. For example, compound A may be 2,6-dichloro-3 nitro pyridine.
[0000]
[0090] One having skill in the art will recognize Scheme 1 may be used to synthesize compounds having the general formula of (Ia), (Ib), (Ic) and (Id).
[0091] According to another embodiment of the invention, the activity of the p38 inhibitors of this invention may be assayed in vitro, in vivo or in a cell line. In vitro assays include assays that determine inhibition of either the kinase activity or ATPase activity of activated p38. Alternate in vitro assays quantitate the ability of the inhibitor to bind to p38 and may be measured either by radiolabelling the inhibitor prior to binding, isolating the inhibitor/p38 complex and determining the amount of radiolabel bound, or by running a competition experiment where new inhibitors are incubated with p38 bound to known radioligands.
[0092] Cell culture assays of the inhibitory effect of the compounds of this invention may determine the amounts of TNF, IL-1, IL-6 or IL-8 produced in whole blood or cell fractions thereof in cells treated with inhibitor as compared to cells treated with negative controls. Level of these cytokines may be determined through the use of commercially available ELISAs.
[0093] An in vivo assay useful for determining the inhibitory activity of the p38 inhibitors of this invention are the suppression of hind paw edema in rats with Mycobacterium butyricum -induced adjuvant arthritis. This is described in J. C. Boehm et al., J. Med. Chem., 39, pp. 3929-37 (1996), the disclosure of which is herein incorporated by reference. The p38 inhibitors of this invention may also be assayed in animal models of arthritis, bone resorption, endotoxin shock and immune function, as described in A. M. Badger et al., J. Pharmacol. Experimental Therapeutics, 279, pp. 1453-61 (1996), the disclosure of which is herein incorporated by reference.
[0094] The p38 inhibitors or pharmaceutical salts thereof may be formulated into pharmaceutical compositions for administration to animals or humans. These pharmaceutical compositions, which comprise an amount of p38 inhibitor effective to treat or prevent a p38-mediated condition and a pharmaceutically acceptable carrier, are another embodiment of the present invention.
[0095] The term “p38-mediated condition”, as used herein means any disease or other deleterious condition in which p38 is known to play a role. This includes conditions known to be caused by IL-1, TNF, IL-6 or IL-8 overproduction. Such conditions include, without limitation, inflammatory diseases, autoimmune diseases, destructive bone disorders, proliferative disorders, infectious diseases, neurodegenerative diseases, allergies, reperfusion/ischemia in stroke, heart attacks, angiogenic disorders, organ hypoxia, vascular hyperplasia, cardiac hypertrophy, thrombin-induced platelet aggregation, and conditions associated with prostaglandin endoperoxidase synthase-2.
[0096] Inflammatory diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, acute pancreatitis, chronic pancreatitis, asthma, allergies, and adult respiratory distress syndrome.
[0097] Autoimmune diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, glomerulonephritis, rheumatoid arthritis, systemic lupus erythematosus, scleroderma, chronic thyroiditis, Graves' disease, autoimmune gastritis, diabetes, autoimmune hemolytic anemia, autoimmune neutropenia, thrombocytopenia, atopic dermatitis, chronic active hepatitis, myasthenia gravis, multiple sclerosis, inflammatory bowel disease, ulcerative colitis, Crohn's disease, psoriasis, or graft vs. host disease.
[0098] Destructive bone disorders which may be treated or prevented by the compounds of this invention include, but are not limited to, osteoporosis, osteoarthritis and multiple myeloma-related bone disorder.
[0099] Proliferative diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, acute myelogenous leukemia, chronic myelogenous leukemia, metastatic melanoma, Kaposi's sarcoma, and multiple myeloma.
[0100] Angiogenic disorders which may be treated or prevented by the compounds of this invention include solid tumors, ocular neovasculization, infantile haemangiomas.
[0101] Infectious diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, sepsis, septic shock, and Shigellosis.
[0102] Viral diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, acute hepatitis infection (including hepatitis A, hepatitis B and hepatitis C), HIV infection and CMV retinitis.
[0103] Neurodegenerative diseases which may be treated or prevented by the compounds of this invention include, but are not limited to, Alzheimer's disease, Parkinson's disease, cerebral ischemias or neurodegenerative disease caused by traumatic injury.
[0104] “p38-mediated conditions” also include ischemia/reperfusion in stroke, heart attacks, myocardial ischemia, organ hypoxia, vascular hyperplasia, cardiac hypertrophy, and thrombin-induced platelet aggregation.
[0105] In addition, p38 inhibitors of the instant invention are also capable of inhibiting the expression of inducible pro-inflammatory proteins such as prostaglandin endoperoxide synthase-2 (PGHS-2), also referred to as cyclooxygenase-2 (COX-2). Therefore, other “p38-mediated conditions” which may be treated by the compounds of this invention include edema, analgesia, fever and pain, such as neuromuscular pain, headache, cancer pain, dental pain and arthritis pain.
[0106] The diseases that may be treated or prevented by the p38 inhibitors of this invention may also be conveniently grouped by the cytokine (IL-1, TNF, IL-6, IL-8) that is believed to be responsible for the disease.
[0107] Thus, an IL-1-mediated disease or condition includes rheumatoid arthritis, osteoarthritis, stroke, endotoxemia and/or toxic shock syndrome, inflammatory reaction induced by endotoxin, inflammatory bowel disease, tuberculosis, atherosclerosis, muscle degeneration, cachexia, psoriatic arthritis, Reiter's syndrome, gout, traumatic arthritis, rubella arthritis, acute synovitis, diabetes, pancreatic β-cell disease and Alzheimer's disease.
[0108] TNF-mediated disease or condition includes, rheumatoid arthritis, rheumatoid spondylitis, osteoarthritis, gouty arthritis and other arthritic conditions, sepsis, septic shock, endotoxic shock, gram negative sepsis, toxic shock syndrome, adult respiratory distress syndrome, cerebral malaria, chronic pulmonary inflammatory disease, silicosis, pulmonary sarcoidosis, bone resorption diseases, reperfusion injury, graft vs. host reaction, allograft rejections, fever and myalgias due to infection, cachexia secondary to infection, AIDS, ARC or malignancy, keloid formation, scar tissue formation, Crohn's disease, ulcerative colitis or pyresis. TNF-mediated diseases also include viral infections, such as HIV, CMV, influenza and herpes; and veterinary viral infections, such as lentivirus infections, including, but not limited to equine infectious anemia virus, caprine arthritis virus, visna virus or maedi virus; or retrovirus infections, including feline immunodeficiency virus, bovine immunodeficiency virus, or canine immunodeficiency virus.
[0109] IL-8 mediated disease or condition includes diseases characterized by massive neutrophil infiltration, such as psoriasis, inflammatory bowel disease, asthma, cardiac and renal reperfusion injury, adult respiratory distress syndrome, thrombosis and glomerulonephritis.
[0110] In addition, the compounds of this invention may be used topically to treat or prevent conditions caused or exacerbated by IL-1 or TNF. Such conditions include inflamed joints, eczema, psoriasis, inflammatory skin conditions such as sunburn, inflammatory eye conditions such as conjunctivitis, pyresis, pain and other conditions associated with inflammation.
[0111] According to another embodiment, the compounds of this invention may be used to treat ZAP70-mediated conditions including, without limitation, organ or tissue rejection associated with transplantation, autoimmune disease, e.g., rheumatoid arthritis, systemic lupus erythematosus (SLE), psoriasis, Sjogren's Syndrome, thyroiditis, pulmonary fibrosis, bronchiolitis obliterans, hemolytic anemia and Wegener's granulomatosis, cancer, including leukemia and lymphoma, multiple sclerosis, graft versus host disease, and Kawasaki syndrome.
[0112] The ZAP70 inhibitors or pharmaceutical salts thereof may be formulated into pharmaceutical compositions for administration to animals or humans. These pharmaceutical compositions, which comprise an amount of ZAP70 inhibitor effective to treat or prevent a ZAP70-mediated condition and a pharmaceutically acceptable carrier, are another embodiment of the present invention.
[0113] In addition to the compounds of this invention, pharmaceutically acceptable salts of the compounds of this invention may also be employed in compositions to treat or prevent the above-identified disorders.
[0114] Pharmaceutically acceptable salts of the compounds of this invention include those derived from pharmaceutically acceptable inorganic and organic acids and bases. Examples of suitable acid salts include acetate, adipate, alginate, aspartate, benzoate, benzenesulfonate, bisulfate, butyrate, citrate, camphorate, camphorsulfonate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptanoate, glycerophosphate, glycolate, hemisulfate, heptanoate, hexanoate, hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate, lactate, maleate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oxalate, palmoate, pectinate, persulfate, 3-phenylpropionate, phosphate, picrate, pivalate, propionate, salicylate, succinate, sulfate, tartrate, thiocyanate, tosylate and undecanoate. Other acids, such as oxalic, while not in themselves pharmaceutically acceptable, may be employed in the preparation of salts useful as intermediates in obtaining the compounds of the invention and their pharmaceutically acceptable acid addition salts. Salts derived from appropriate bases include alkali metal (e.g., sodium and potassium), alkaline earth metal (e.g., magnesium), ammonium and N—(C1-4 alkyl)4+ salts. This invention also envisions the quaternization of any basic nitrogen-containing groups of the compounds disclosed herein. Water or oil-soluble or dispersible products may be obtained by such quaternization.
[0115] Pharmaceutically acceptable carriers that may be used in these pharmaceutical compositions include, but are not limited to, ion exchangers, alumina, aluminum stearate, lecithin, serum proteins, such as human serum albumin, buffer substances such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, salts or electrolytes, such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone, cellulose-based substances, polyethylene glycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropylene-block polymers, polyethylene glycol and wool fat.
[0116] The compositions of the present invention may be administered orally, parenterally, by inhalation spray, topically, rectally, nasally, buccally, vaginally or via an implanted reservoir. The term “parenteral” as used herein includes subcutaneous, intravenous, intramuscular, intra-articular, intra-synovial, intrasternal, intrathecal, intrahepatic, intralesional and intracranial injection or infusion techniques. Preferably, the compositions are administered orally, intraperitoneally or intravenously.
[0117] Sterile injectable forms of the compositions of this invention may be aqueous or oleaginous suspension. These suspensions may be formulated according to techniques known in the art 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. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, 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 di-glycerides. Fatty acids, such as oleic acid and its glyceride derivatives are useful in the preparation of injectables, as are natural pharmaceutically-acceptable oils, such as olive oil or castor oil, especially in their polyoxyethylated versions. These oil solutions or suspensions may also contain a long-chain alcohol diluent or dispersant, such as carboxymethyl cellulose or similar dispersing agents which are commonly used in the formulation of pharmaceutically acceptable dosage forms including emulsions and suspensions. Other commonly used surfactants, such as Tweens, Spans and other emulsifying agents or bioavailability enhancers which are commonly used in the manufacture of pharmaceutically acceptable solid, liquid, or other dosage forms may also be used for the purposes of formulation.
[0118] The pharmaceutical compositions of this invention may be orally administered in any orally acceptable dosage form including, but not limited to, capsules, tablets, aqueous suspensions or solutions. In the case of tablets for oral use, carriers commonly used include lactose and corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, useful diluents include lactose and dried cornstarch. When aqueous suspensions are required for oral use, the active ingredient is combined with emulsifying and suspending agents. If desired, certain sweetening, flavoring or coloring agents may also be added.
[0119] Alternatively, the pharmaceutical compositions of this invention may be administered in the form of suppositories for rectal administration. These can be prepared by mixing the agent with a suitable non-irritating excipient which is solid at room temperature but liquid at rectal temperature and therefore will melt in the rectum to release the drug. Such materials include cocoa butter, beeswax and polyethylene glycols.
[0120] The pharmaceutical compositions of this invention may also be administered topically, especially when the target of treatment includes areas or organs readily accessible by topical application, including diseases of the eye, the skin, or the lower intestinal tract. Suitable topical formulations are readily prepared for each of these areas or organs.
[0121] Topical application for the lower intestinal tract can be effected in a rectal suppository formulation (see above) or in a suitable enema formulation. Topically-transdermal patches may also be used.
[0122] For topical applications, the pharmaceutical compositions may be formulated in a suitable ointment containing the active component suspended or dissolved in one or more carriers. Carriers for topical administration of the compounds of this invention include, but are not limited to, mineral oil, liquid petrolatum, white petrolatum, propylene glycol, polyoxyethylene, polyoxypropylene compound, emulsifying wax and water. Alternatively, the pharmaceutical compositions can be formulated in a suitable lotion or cream containing the active components suspended or dissolved in one or more pharmaceutically acceptable carriers. Suitable carriers include, but are not limited to, mineral oil, sorbitan monostearate, polysorbate 60, cetyl esters wax, cetearyl alcohol, 2-octyldodecanol, benzyl alcohol and water.
[0123] For ophthalmic use, the pharmaceutical compositions may be formulated as micronized suspensions in isotonic, pH adjusted sterile saline, or, preferably, as solutions in isotonic, pH adjusted sterile saline, either with or without a preservative such as benzylalkonium chloride. Alternatively, for ophthalmic uses, the pharmaceutical compositions may be formulated in an ointment such as petrolatum.
[0124] The pharmaceutical compositions of this invention may also be administered by nasal aerosol or inhalation. Such compositions are prepared according to techniques well-known in the art of pharmaceutical formulation and may be prepared as solutions in saline, employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other conventional solubilizing or dispersing agents.
[0125] The amount of p38 or ZAP70 inhibitor that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. Preferably, the compositions should be formulated so that a dosage of between 0.01-100 mg/kg body weight/day of the inhibitor can be administered to a patient receiving these compositions.
[0126] It should also be understood that a specific dosage and treatment regimen for any particular patient will depend upon a variety of factors, including the activity of the specific compound employed, the age, body weight, general health, sex, diet, time of administration, rate of excretion, drug combination, and the judgment of the treating physician and the severity of the particular disease being treated. The amount of inhibitor will also depend upon the particular compound in the composition.
[0127] According to another embodiment, the invention provides methods for treating or preventing a p38-mediated condition comprising the step of administering to a patient one of the above-described pharmaceutical compositions. The term “patient”, as used herein, means an animal, preferably a human.
[0128] Preferably, that method is used to treat or prevent a condition selected from inflammatory diseases, autoimmune diseases, destructive bone disorders, proliferative disorders, infectious diseases, degenerative diseases, allergies, reperfusion/ischemia in stroke, heart attacks, angiogenic disorders, organ hypoxia, vascular hyperplasia, cardiac hypertrophy, and thrombin-induced platelet aggregation.
[0129] According to another embodiment, the inhibitors of this invention are used to treat or prevent an IL-1, IL-6, IL-8 or TNF-mediated disease or condition. Such conditions are described above.
[0130] Depending upon the particular p38-mediated condition to be treated or prevented, additional drugs, which are normally administered to treat or prevent that condition, may be administered together with the inhibitors of this invention. For example, chemotherapeutic agents or other anti-proliferative agents may be combined with the p38 inhibitors of this invention to treat proliferative diseases.
[0131] Those additional agents may be administered separately, as part of a multiple dosage regimen, from the p38 inhibitor-containing composition. Alternatively, those agents may be part of a single dosage form, mixed together with the p38 inhibitor in a single composition.
[0132] According to another embodiment, the invention provides methods for treating or preventing a ZAP70-mediated condition comprising the step of administering to a patient one of the above-described pharmaceutical compositions.
[0133] In order that the invention described herein may be more fully understood, the following examples are set forth. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this invention in any manner.
Example 1
Synthesis of p38 Inhibitor Compound 7
[0134]
[0135] To a solution of LDA (60 mmol, 40 mLs) at −78° C., was added dropwise a solution of 2,6-dibromopyridine (40 mmol, 9.48 gms) in THF (30 mLs, dried). The mixture was stirred at −78° C. for 20 minutes. Ethyl formate (400 mmol, 32.3 mLs) was added and stirring was continued at −78° C. for 2 hours. Saturated ammonium chloride (200 mLs) was added and the mixture was warmed to room temperature. The reaction mixture was diluted with ethyl acetate and the organic layer was washed with aqueous acid and base. The organic layer was dried and evaporated in vacuo. The resulting material was purified by flash chromatography on silica gel followed by eluting with 10% ethyl acetate in n-hexane to afford 1 (32 mmol, 8.41 gms) as a white solid.
[0000]
[0136] A solution of 1 (776 mmol, 205.6 gms) and triethyl orthoformate (200 mL) dissolved in ethanol (750 mL) was refluxed overnight. The reaction mixture was cooled, and evaporated in vacuo. The remaining red oil was dissolved in hexane and filtered over a plug of silica gel. The plug was eluted with 50% CH 2 Cl 2 /hexane. The filtrate was evaporated to afford 2 as an oil.
[0000]
[0137] To a suspension of 60% NaH (130 mmol, 5.20 g) and 2 (61.2 mmol, 20.76 g) in THF (100 mL) at reflux was added dropwise a solution of 2,6-difluoroaniline (61.3 mmol, 20 g) in THF (100 mL). After the aniline had been added, Pd(PPh 3 ) 4 (100 mg) was added. The mixture was refluxed for one hour and cooled. Hydrochloric acid (1N, 100 mL) was added and stirring was continued for one hour. The reaction mixture was extracted with CH 2 Cl 2 . The organic extract was dried and evaporated in vacuo. The resulting material was dissolved in a minimal amount of CH 2 Cl 2 and hexane was added. The solution was cooled precipitating 3 as a yellow solid.
[0000]
[0138] p-fluorophenylboronic acid (57.5 mmol, 8.05 g), and 3 (46.9 mmol, 14.70 g) were dissolved in a dimethoxyethane (300 mL). Cesium fluoride (68.6 mmol, 10.42 g) and tetrakis(triphenylphosphine)palladium (0) (100 mgs) were added to the solution and the suspension was allowed to reflux overnight. The reaction mixture was poured into water and extracted with CH 2 Cl 2 . The organic extract was washed with 1N NaOH, dried with MgSO 4 , and filtered over a plug of silica gel. The plug was eluted with CH 2 Cl 2 and the filtrate was evaporated in vacuo. The resulting yellow solid was triturated with 50% CH 2 Cl 2 /hexane to afford 4 (9.50 g, 62%) as a yellow solid.
[0000]
[0139] A solution of 4 (70.1 mmol, 23.01 g) in toluene (250 mL) was combined with a 20% solution of phosgene in toluene (151 mmol, 80 mL) and heated to reflux for two hours. The reaction was cooled and poured into ammonium hydroxide. The mixture was stirred for five minutes and extracted with methylene chloride. The organic extract was dried and filtered over a plug of silica gel. The plug was eluted with methylene chloride to remove residual starting material. It was then eluted with 50% ethyl acetate/methylene chloride to obtain 5. The filtrate was evaporated in vacuo to afford 5 (21.38 g, 86%) as a white solid.
[0000]
[0140] Sodium borohydride (36.5 mmol, 1.38 g) was added to a solution of 5 (60.0 mmol, 21.38 g) in THF (100 mL) and the solution was stirred for one hour at 0° C. and then two hours at room temperature. The reaction was poured into 1N HCl and extracted with methylene chloride. The organic extract was dried and filtered over a plug of silica gel. The plug was eluted with 5% ethyl acetate/methylene chloride to remove residual starting material. It was then eluted with ethyl acetate to obtain 6. The filtrate was evaporated to afford 6 as a white solid.
[0141] The spectral data for compound 6 was:
[0142] 1 H NMR (500 MHz, CDCl 3 ) δ 7.90 (d, 1H), 7.60 (d, 2H), 7.5-7.3 (m, 5H), 6.30 (d, 2H), 4.5 (s, 2H), 2.3 (s, 2H).
[0000]
[0143] A solution of 6 (2.79 mmol, 1.00 g) and p-nitrophenyl chloroformate (5.56 mmol, 1.12 g) was cooled to 0° C. Triethylamine (14.3 mmol, 2.0 mL) was added and the solution was stirred for 15 minutes and poured into ammonium hydroxide. The solution mixture was poured into water and extracted with methylene chloride. The organic extract was washed with saturated aqueous sodium bicarbonate, dried, and evaporated in vacuo to afford 7 (730 mg, 65%) as a white solid.
Example 2
Synthesis of p38 Inhibitor Prodrugs 9 and 10
[0144]
[0145] A mixture of 8 (1.0 g, 2.30 mmol) and N,N-dimethylformamide dimethyl acetal (1.01 g, 6.91 mmol) in 10 mL of toluene was heated to 80° C. for 20 minutes. The resulting solution was cooled to room temperature. Normal workup followed by chromatography on silica gel (hexane/EtOAc:10/4) gave amidine 9 (compound 101 of Table 1) as a white solid. The spectral data for compound 9 was: 1 H NMR (500 MHz, CDCl 3 ) δ 8.3 (s, 1H), 7.7 (d, 1H), 7.5-7.4 (m, 1H), 7.1-7.0 (m, 1H), 6.95-6.85 (t, 2H), 6.85-6.75 (m, 1H), 6.45-6.4 (d, 1H), 6.2 (s, 1H), 4.95 (s, 2H), 3.05 (s, 3H), 2.95 (s, 3H).
[0000]
[0146] A mixture of 8 (1.0 g, 2.30 mmol) and N,N-dimethylformamide dimethyl acetal (3.3 g, 22.4 mmol) in 10 mL of toluene was heated to 8° C. for 90 minutes. The resulting solution was cooled to room temperature. Normal workup followed by chromatography on silica gel (hexane/EtOAc:2/1) gave bis-amidine 10 (compound 107 of Table 1) as a white solid. The spectral data for compound 10 was: 1 H NMR (500 MHz, CDCl 3 ) δ 8.4 (s, 1H), 8.3 (s, 1H), 8.05-7.95 (s, 1H), 7.15-7.05 (m, 2H), 6.85-6.75 (t, 2H), 6.75-6.65 (m, 4H), 4.95 (s, 2H), 3.0-2.95 (d, 9H); 2.65 (s, 3H).
Example 3
Synthesis of p38 Inhibitor Prodrug 13
[0147]
[0148] To a mixture of 6 (1.25 gm, 3.35 mmol) and 4-nitrophenyl chloroformate (0.81 gm, 4.02 mmol) in tetrahydrofuran (30 mL) was added triethylamine (1.16 mL, 8.38 mmol) dropwise at 0° C. The resulting slurry was allowed to stir at 0° C. for 30 minutes. Ethanolamine (0.6 mL, 10.0 mmol) was added and the solution was stirred at 0° C. for 30 minutes. Normal work-up followed by chromatography on silica (hexane/acetone:10/4) gave 11 (1.03 gm, 2.23 mmol) as a white solid. 1 H NMR (500 MHz, CDCl 3 ) 7.75 (d, 1H), 7.65-7.55 (m, 2H), 7.5-7.4 (m, 1H), 7.25-7.15 (t, 2H), 7.15-7.05 (t, 2H), 6.4 (d, 1H), 5.2-5.1 (bs, 1H), 5.15 (s, 2H), 3.75-3.65 (t, 2H), 3.4-3.3 (m, 2H).
[0000]
[0149] A mixture of 11 (1.03 gm, 2.23 mmol), (L)-BOC-Val-OH (0.97 gm, 4.46 mmol), and 1-(3-dimethylaminopropyl) 3-ethylcarbodiimide hydrochloride in methylene chloride (30 mL) was stirred at room temperature for 1.5 hours. Normal work-up followed by chromatography on silica (hexane/acetone:10/4) gave Val deriv. 12 (1.38 gms, 2.09 mmol) as a white solid. 1 H NMR (500 MHz, CDCl 3 )7.75 (d, 1H), 7.65-7.55 (m, 2H), 7.5-7.4 (m, 1H), 7.25-7.15 (t, 2H), 7.15-7.05 (t, 2H), 6.4 (d, 1H), 5.40-5.35 (bs, 1H), 5.05 (s, 2H), 5.00-4.95 (d, 1H), 4.4-4.3 (m, 1H), 4.25-4.15 (m, 1H), 4.15-4.05 (m, 1H), 3.55-3.45 (m, 2H), 2.15-2.05 (m, 1H), 1.45 (s, 9H), 1.0-0.85 (m, 6H).
[0000]
[0150] To a solution of 12 (1.38 gms, 2.09 mmol) in methylene chloride (20 mLs) was added trifluoroacetic acid (10 mLs). The solution was allowed to stir at room temperature for 1 hour. Normal work-up gave a white solid that was converted to its hydrochloride salt to give 13 (compound 111 of Table 2; 0.61 gms, 1.02 mmol) as a white solid. The spectral data for compound 13 was: 1 H NMR (500 MHz, CDCl 3 ) 7.65 (d, 1H), 7.55-7.45 (m, 2H), 7.4-7.3 (m, 1H), 7.15-7.05 (m, 2H), 7.05-6.95 (m, 2H), 6.35 (d, 1H), 5.05-5.00 (bs, 1H), 4.95 (s, 2H), 4.15-4.05 (m, 2H), 3.45-3.25 (m, 2H), 3.2 (s, 1H), 1.95-1.85 (m, 1H), 0.90-0.75 (m, 6H).
Example 4
Cloning of p38 Kinase in Insect Cells
[0151] Two splice variants of human p38 kinase, CSBP1 and CSBP2, have been identified. Specific oligonucleotide primers were used to amplify the coding region of CSBP2 cDNA using a HeLa cell library (Stratagene) as a template. The polymerase chain reaction product was cloned into the pET-15b vector (Novagen). The baculovirus transfer vector, pVL-(His)6-p38 was constructed by subcloning a XbaI-BamHI fragment of pET15b-(His)6-p38 into the complementary sites in plasmid pVL1392 (Pharmingen).
[0152] The plasmid pVL-(His)6-p38 directed the synthesis of a recombinant protein consisting of a 23-residue peptide (MGSSHHHHHHSSGLVPRGSHMLE, where LVPRGS represents a thrombin cleavage site) fused in frame to the N-terminus of p38, as confirmed by DNA sequencing and by N-terminal sequencing of the expressed protein. Monolayer culture of Spodoptera frugiperda (Sf9) insect cells (ATCC) was maintained in TNM-FH medium (Gibco BRL) supplemented with 10% fetal bovine serum in a T-flask at 27° C. Sf9 cells in log phase were co-transfected with linear viral DNA of Autographa califonica nuclear polyhedrosis virus (Pharmingen) and transfer vector pVL-(His) 6-p38 using Lipofectin (Invitrogen). The individual recombinant baculovirus clones were purified by plaque assay using 1% low melting agarose.
Example 5
Expression and Purification of Recombinant p38 Kinase
[0153] Trichoplusia ni (Tn-368) High-Five™ cells (Invitrogen) were grown in suspension in Excel-405 protein free medium (JRH Bioscience) in a shaker flask at 27° C. Cells at a density of 1.5×10 6 cells/ml were infected with the recombinant baculovirus described above at a multiplicity of infection of 5. The expression level of recombinant p38 was monitored by immunoblotting using a rabbit anti-p38 antibody (Santa Cruz Biotechnology). The cell mass was harvested 72 hours after infection when the expression level of p38 reached its maximum.
[0154] Frozen cell paste from cells expressing the (His) 6 -tagged p38 was thawed in 5 volumes of Buffer A (50 mM NaH 2 PO 4 pH 8.0, 200 mM NaCl, 2 mM β-Mercaptoethanol, 10% Glycerol and 0.2 mM PMSF). After mechanical disruption of the cells in a microfluidizer, the lysate was centrifuged at 30,000×g for 30 minutes. The supernatant was incubated batchwise for 3-5 hours at 4° C. with Talon™ (Clontech) metal affinity resin at a ratio of 1 ml of resin per 2-4 mgs of expected p38. The resin was settled by centrifugation at 500×g for 5 minutes and gently washed batchwise with Buffer A. The resin was slurried and poured into a column (approx. 2.6×5.0 cm) and washed with Buffer A+5 mM imidazole.
[0155] The (His) 6 -p38 was eluted with Buffer A+100 mM imidazole and subsequently dialyzed overnight at 4° C. against 2 liters of Buffer B, (50 mM HEPES, pH 7.5, 25 mM β-glycerophosphate, 5% glycerol, 2 mM DTT). The His 6 tag was removed by addition of at 1.5 units thrombin (Calbiochem) per mg of p38 and incubation at 20° C. for 2-3 hours. The thrombin was quenched by addition of 0.2 mM PMSF and then the entire sample was loaded onto a 2 ml benzamidine agarose (American International Chemical) column.
[0156] The flow through fraction was directly loaded onto a 2.6×5.0 cm Q-Sepharose (Pharmacia) column previously equilibrated in Buffer B+0.2 mM PMSF. The p38 was eluted with a 20 column volume linear gradient to 0.6M NaCl in Buffer B. The eluted protein peak was pooled and dialyzed overnight at 4° C. vs. Buffer C (50 mM HEPES pH 7.5, 5% glycerol, 50 mM NaCl, 2 mM DTT, 0.2 mM PMSF).
[0157] The dialyzed protein was concentrated in a Centriprep (Amicon) to 3-4 ml and applied to a 2.6×100 cm Sephacryl S-100HR (Pharmacia) column. The protein was eluted at a flow rate of 35 ml/hr. The main peak was pooled, adjusted to 20 mM DTT, concentrated to 10-80 mgs/ml and frozen in aliquots at −70° C. or used immediately.
Example 6
Activation of p38
[0158] p38 was activated by combining 0.5 mg/ml p38 with 0.005 mg/ml DD-double mutant MKK6 in Buffer B+10 mM MgCl 2 , 2 mM ATP, 0.2 mM Na 2 VO 4 for 30 minutes at 20° C. The activation mixture was then loaded onto a 1.0×10 cm MonoQ column (Pharmacia) and eluted with a linear 20 column volume gradient to 1.0 M NaCl in Buffer B. The activated p38 eluted after the ADP and ATP. The activated p38 peak was pooled and dialyzed against buffer B+0.2 mM Na 2 VO 4 to remove the NaCl. The dialyzed protein was adjusted to 1.1M potassium phosphate by addition of a 4.0M stock solution and loaded onto a 1.0×10 cm HIC (Rainin Hydropore) column previously equilibrated in Buffer D (10% glycerol, 20 mM B-glycerophosphate, 2.0 mM DTT)+1.1MK 2 HPO 4 . The protein was eluted with a 20 column volume linear gradient to Buffer D+50 mM K 2 HPO 4 . The double phosphorylated p38 eluted as the main peak and was pooled for dialysis against Buffer B+0.2 mM Na 2 VO 4 . The activated p38 was stored at −70° C.
Example 7
p38 Inhibition Assays
A. Inhibition of Phosphorylation of EGF Receptor Peptide
[0159] This assay was carried out in the presence of 10 mM MgCl 2 , 25 mM β-glycerophosphate, 10% glycerol and 100 mM HEPES buffer at pH 7.6. For a typical IC 50 determination, a stock solution was prepared containing all of the above components and activated p38 (5 nM). The stock solution was aliquoted into vials. A fixed volume of DMSO or inhibitor in DMSO (final concentration of DMSO in reaction was 5%) was introduced to each vial, mixed and incubated for 15 minutes at room temperature. EGF receptor peptide, KRELVEPLTPSGEAPNQALLR, a phosphoryl acceptor in p38-catalyzed kinase reaction (1), was added to each vial to a final concentration of 200 μM. The kinase reaction was initiated with ATP (100 μM) and the vials were incubated at 30° C. After 30 minutes, the reactions were quenched with equal volume of 10% trifluoroacetic acid (TFA).
[0160] The phosphorylated peptide was quantified by HPLC analysis. Separation of phosphorylated peptide from the unphosphorylated peptide was achieved on a reverse phase column (Deltapak, 5 μm, C18 100D, Part no. 011795) with a binary gradient of water and acteonitrile, each containing 0.1% TFA. IC 50 (concentration of inhibitor yielding 50% inhibition) was determined by plotting the percent (%) activity remaining against inhibitor concentration.
B. Inhibition of ATPase Activity
[0161] This assay is carried out in the presence of 10 mM MgCl 2 , 25 mM β-glycerophosphate, 10% glycerol and 100 mM HEPES buffer at pH 7.6. For a typical Ki determination, the Km for ATP in the ATPase activity of activated p38 reaction is determined in the absence of inhibitor and in the presence of two concentrations of inhibitor. A stock solution is prepared containing all of the above components and activated p38 (60 nM). The stock solution is aliquoted into vials. A fixed volume of DMSO or inhibitor in DMSO (final concentration of DMSO in reaction was 2.5%) is introduced to each vial, mixed and incubated for 15 minutes at room temperature. The reaction is initiated by adding various concentrations of ATP and then incubated at 30° C. After 30 minutes, the reactions are quenched with 50 μl of EDTA (0.1 M, final concentration), pH 8.0. The product of p38 ATPase activity, ADP, is quantified by HPLC analysis.
[0162] Separation of ADP from ATP is achieved on a reversed phase column (Supelcosil, LC-18, 3 μm, part no. 5-8985) using a binary solvent gradient of following composition: Solvent A-0.1 M phosphate buffer containing 8 mM tetrabutylammonium hydrogen sulfate (Sigma Chemical Co., catalogue no. T-7158), Solvent B-Solvent A with 30% methanol.
[0163] Ki is determined from the rate data as a function of inhibitor and ATP concentrations.
[0164] p38 inhibitors of this invention will inhibit the ATPase activity of p38.
C. Inhibition of IL-1, TNF, IL-6 and IL-8 Production in LPS-Stimulated PBMCs
[0165] Inhibitors were serially diluted in DMSO from a 20 mM stock. At least 6 serial dilutions were prepared. Then 4× inhibitor stocks were prepared by adding 4 μl of an inhibitor dilution to 1 ml of RPMI1640 medium/10% fetal bovine serum. The 4× inhibitor stocks contained inhibitor at concentrations of 80 μM, 32 μM, 12.8 μM, 5.12 μM, 2.048 μM, 0.819 μM, 0.328 μM, 0.131 μM, 0.052 μM, 0.021 μM etc. The 4× inhibitor stocks were pre-warmed at 37° C. until use.
[0166] Fresh human blood buffy cells were separated from other cells in a Vacutainer CPT from Becton & Dickinson (containing 4 ml blood and enough DPBS without Mg 2+ /Ca 2+ to fill the tube) by centrifugation at 1500×g for 15 min. Peripheral blood mononuclear cells (PBMCs), located on top of the gradient in the Vacutainer, were removed and washed twice with RPMI1640 medium/10% fetal bovine serum. PBMCs were collected by centrifugation at 500×g for 10 min. The total cell number was determined using a Neubauer Cell Chamber and the cells were adjusted to a concentration of 4.8×10 6 cells/ml in cell culture medium (RPMI1640 supplemented with 10% fetal bovine serum).
[0167] Alternatively, whole blood containing an anti-coagulant was used directly in the assay.
[0168] 100 μl of cell suspension or whole blood were placed in each well of a 96-well cell culture plate. Then 50 μl of the 4× inhibitor stock was added to the cells. Finally, 50 μl of a lipopolysaccharide (LPS) working stock solution (16 ng/ml in cell culture medium) was added to give a final concentration of 4 ng/ml LPS in the assay. The total assay volume of the vehicle control was also adjusted to 200 μl by adding 50 μl cell culture medium. The PBMC cells or whole blood were then incubated overnight (for 12-15 hours) at 37° C./5% CO 2 in a humidified atmosphere.
[0169] The next day the cells were mixed on a shaker for 3-5 minutes before centrifugation at 500×g for 5 minutes. Cell culture supernatants were harvested and analyzed by ELISA for levels of IL-1β (R & D Systems, Quantikine kits, #DBL50), TNF-α (BioSource, #KHC3012), IL-6 (Endogen, #EH2-IL6) and IL-8 (Endogen, #EH2-IL8) according to the instructions of the manufacturer. The ELISA data were used to generate dose-response curves from which IC50 values were derived.
[0170] Results for the kinase assay (“kinase”; subsection A, above), IL-1, and TNF in LPS-stimulated PBMC's (“cell”) and IL-1, TNF, and IL-6 in whole blood (“WB”) for various p38 inhibitors of this invention are shown in Table 7 below:
[0000]
TABLE 7
Cell
Cell
WB
WB
WB
IL-1
TNF
IL-1
TNF
IL-6
Kinase IC50
IC50
IC50
IC50
IC50
IC50
Compound
M.W.
(uM)
(uM)
(uM)
(uM)
(uM)
(uM)
13
559.55
0.031
0.012
0.022
0.140
0.055
0.083
9
489.43
1.0
0.05
0.05
12.2
20.0
11.0
10
544.51
5.0
2.2
4.3
0.8
[0171] Other p38 inhibitors of this invention will also inhibit phosphorylation of EGF receptor peptide, and will inhibit the production of IL-1, TNF and IL-6, as well as IL-8, in LPS-stimulated PBMCs or in whole blood.
D. Inhibition of IL-6 and IL-8 Production in IL-1-Stimulated PBMCs
[0172] This assay is carried out on PBMCs exactly the same as above except that 50 μl of an IL-1b working stock solution (2 ng/ml in cell culture medium) is added to the assay instead of the (LPS) working stock solution.
[0173] Cell culture supernatants are harvested as described above and analyzed by ELISA for levels of IL-6 (Endogen, #EH2-IL6) and IL-8 (Endogen, #EH2-IL8) according to the instructions of the manufacturer. The ELISA data are used to generate dose-response curves from which IC50 values were derived.
E. Inhibition of LPS-Induced Prostaglandin Endoperoxide Synthase-2 (PGHS-2, or COX-2) Induction in PBMCs
[0174] Human peripheral mononuclear cells (PBMCs) are isolated from fresh human blood buffy coats by centrifugation in a Vacutainer CPT (Becton & Dickinson). 15×10 6 cells are seeded in a 6-well tissue culture dish containing RPMI 1640 supplemented with 10% fetal bovine serum, 50 U/ml penicillin, 50 μg/ml streptomycin, and 2 mM L-glutamine. Compounds are added at 0.2, 2.0 and 20 μM final concentrations in DMSO. LPS is then added at a final concentration of 4 ng/ml to induce enzyme expression. The final culture volume is 10 ml/well.
[0175] After overnight incubation at 37° C., 5% CO 2 , the cells are harvested by scraping and subsequent centrifugation, the supernatant is removed, and the cells are washed twice in ice-cold DPBS (Dulbecco's phosphate buffered saline, BioWhittaker). The cells are lysed on ice for 10 min in 50 μl cold lysis buffer (20 mM Tris-HCl, pH 7.2, 150 mM NaCl, 1% Triton-X-100, 1% deoxycholic acid, 0.1% SDS, 1 mM EDTA, 2% aprotinin (Sigma), 10 μg/ml pepstatin, 10 μg/ml leupeptin, 2 mM PMSF, 1 mM benzamidine, 1 mM DTT) containing 1 μl Benzonase (DNAse from Merck). The protein concentration of each sample is determined using the BCA assay (Pierce) and bovine serum albumin as a standard. Then the protein concentration of each sample is adjusted to 1 mg/ml with cold lysis buffer. To 100 μl lysate an equal volume of 2×SDS PAGE loading buffer is added and the sample is boiled for 5 min. Proteins (30 μg/lane) are size-fractionated on 4-20% SDS PAGE gradient gels (Novex) and subsequently transferred onto nitrocellulose membrane by electrophoretic means for 2 hours at 100 mA in Towbin transfer buffer (25 mM Tris, 192 mM glycine) containing 20% methanol. After transfer, the membrane is pretreated for 1 hour at room temperature with blocking buffer (5% non-fat dry milk in DPBS supplemented with 0.1% Tween-20) and washed 3 times in DPBS/0.1% Tween-20. The membrane is incubated overnight at 4° C. with a 1:250 dilution of monoclonal anti-COX-2 antibody (Transduction Laboratories) in blocking buffer. After 3 washes in DPBS/0.1% Tween-20, the membrane is incubated with a 1:1000 dilution of horseradish peroxidase-conjugated sheep antiserum to mouse Ig (Amersham) in blocking buffer for 1 h at room temperature. Then the membrane is washed again 3 times in DPBS/0.1% Tween-20. An ECL detection system (SuperSignal™ CL-HRP Substrate System, Pierce) is used to determine the levels of expression of COX-2.
Example 8
ZAP70 Inhibition Assay
[0176] The activity of ZAP 70 is measured by determining the phosphorylation poly E4Y (Sigma Chemicals, St Louis Mo.) with γ- 33 P ATP (NEN, Boston, Mass.). Reactions are carried out at room temperature in a buffer containing 100 mM HEPES, pH 7.5, 10 mM MgCl 2 , 25 mM NaCl, 1 mM DTT and 0.01% BSA. Final concentrations of ZAP70 and poly E4Y are 20 nM and 5 μM respectively. Test compounds in DMSO (final concentration of compounds was 30 μM in 1.5% DMSO) are added to the reaction mixture containing the above-described components. The reaction is initiated by addition of γ- 33 P ATP (final concentration 20 μM, specific activity=0.018 Ci/mmol). The reaction is allowed to proceed for 12 minutes and then is quenched by the addition of 10% TCA containing 200 mM ATP. The quenched reaction is harvested onto GF/C glass fiber filter plates (Packard, Meriden, Conn.) using a Tomtec 9600 cell harvester (Tomtec, Hamden, Conn.). The plates are washed with 5% TCA containing 1 mM ATP and water. 50 μl of scintillation fluid is added to the plates, which are then counted using a Packard scintillation counter (Packard, Meriden, Conn.). IC50 values for inhibitory compounds were determined using the same assay at a series of compound concentrations.
[0177] While we have hereinbefore presented a number of embodiments of this invention, it is apparent that our basic construction can be altered to provide other embodiments which utilize the methods of this invention. | The present invention relates to inhibitors of p38, a mammalian protein kinase involved cell proliferation, cell death and response to extracellular stimuli. The invention also relates to inhibitors of ZAP70. The invention also relates to methods for producing these inhibitors. The invention also provides pharmaceutical compositions comprising the inhibitors of the invention and methods of utilizing those compositions in the treatment and prevention of various disorders. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Patent Application is a Divisional Application of a co-pending application Ser. No. 13/480,391 with attorney Docket# APOM076 and filed on May 24, 2012. Thus, this application claims the Priority Date of the co-pending application Ser. No. 13/480,391. Also, the Disclosures made in the co-pending application Ser. No. 13/480,391 are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a semiconductor power device and preparation method thereof. Particularly, this invention aims at providing a power device with a bottom source electrode and preparation method thereof.
DESCRIPTION OF THE RELATED ART
[0003] Power consumption of power devices is commonly very high. In the application of DC-DC power converter devices, some metal electrodes of the devices are usually exposed from plastic packaging material coating a semiconductor chip for improving the electrical connection and heat dissipation performance of the devices. For example, as shown in FIG. 1 , US patent application publication U.S.2003/0132531A1 discloses a semiconductor packaging structure 24 with a bottom electrode of a semiconductor chip exposed and used for supporting surface mounting technology. Here, a power MOSFET 10 is arranged in an interior space of a cup-shaped metal can 12 and a drain electrode at one side of the MOSFET 10 is connected to the bottom of the interior space of the cup-shaped metal can 12 through a layer of conductive epoxy 14 , so that the drain electrode of the MOSFET 10 is electrically connected to an extruding edge 22 of the cup-shaped metal can 12 , while a source electrode 18 and a gate electrode (not shown) located at the other side of the MOSFET 10 become sub-flush with the surface of the extruding edge 22 . Low stress and high adhesion epoxy 16 is provided to fill in gaps in the interior space of the cup-shaped metal can 12 surrounding the MOSFET 10 . The semiconductor packaging structure 24 improves the heat dissipation performance. However, it is expensive to form the cup-shaped metal can 12 in actual production. In addition, both the source electrode and the gate electrode of the MOSFET 10 are fixed in the packaging structure 24 , as a result the contact surface of the gate electrode cannot be adjusted to level with the extruding edge 22 , thus it is hard to match the contact surface of the gate electrode with a pad on a PCB (Printed Circuit Board), which limits the application of the semiconductor packaging structure 24 .
[0004] In addition, the resistance of a substrate in the chip of the power device is usually high, this makes the RDSon of the device correspondingly high; therefore, there is a need to reduce the resistance of the substrate of the chip. In a conventional wafer level chip scale packaging (WLCSP), packaging test is performed and ball placement on a wafer (for ball bonding) is carried out after the processing of all power devices in the whole wafer is completely finished, individual IC (Integrated Circuit) is then singulated with its size being same as the desired original chip.
[0005] Given the above description of related prior arts, therefore, there is a need to manufacture ultra thin chips by WLCSP and to apply these chips in power devices.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The embodiment of the present invention is described more sufficiently through the drawings. However, the drawings are only used for explaining and illustrating rather than limiting the scope of the invention.
[0007] FIG. 1 is a cross sectional schematic diagram of the semiconductor packaging structure of the prior art.
[0008] FIGS. 2A-2E are structural schematic diagrams of the power devices according to a first embodiment of the present invention.
[0009] FIGS. 3A-3F are schematic diagrams illustrating a process for preparing the primary packaging structure of the power devices of the present invention.
[0010] FIGS. 4A-4C are cross sectional schematic diagrams illustrating a process for preparing the power devices of the present invention.
[0011] FIGS. 5A-5B are cross sectional schematic diagrams illustrating the power devices according to a second embodiment of the present invention.
[0012] FIGS. 6A-6D are structural schematic diagrams illustrating the power devices according to a third embodiment of the present invention.
[0013] FIGS. 7A-7C are structural schematic diagrams illustrating the power devices according to a fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] FIG. 2A and FIG. 2B are schematic diagrams showing a top view and a bottom view of the power device 100 A of a first embodiment of the present invention. FIG. 2C and FIG. 2D-1 are cross sectional views of the power device 100 A along a plane AA and along a plane BB respectively shown in FIG. 2B . The power device 100 A comprises a lead frame unit including a first base 111 , a second base 112 , a third base 113 and a fourth base 114 (as shown in FIG. 2B ). The thicknesses of all the bases are basically the same and the bases are arranged on the same plane. The first base 111 preferably has a square shape. The third base 113 and the fourth base 114 are arranged at two opposite sides of the first base 111 respectively and extend along the edges of the first base 111 , and the second base 112 is positioned adjacent to the first base 111 between the third base 113 and the fourth base 114 . In one embodiment, the third base 113 and the fourth base 114 are symmetrical relative to the center of the first base 111 , thus the second base 112 is positioned on a line of symmetry of the third base 113 and the fourth base 114 . Usually, a lead frame strip comprises a plurality of such lead frame units with the bases connected to the lead frame strip through connecting bars (not shown).
[0015] As shown in FIG. 2C and FIG. 2D-1 , the power device 100 A also comprises a primary packaging structure 130 that is a completely packaged structure rather than an unpackaged original chip. The primary packaging structure 130 includes a semiconductor chip 131 that is flipped and attached onto the first base 111 and the second base 112 . Conductive epoxy (such as conductive solder or paste) is used for forming a plurality of balls or bumps 132 a - 1 and 132 b - 1 on the front surface of the primary packaging structure 130 for attaching it onto the second base 112 and the first base 111 respectively. As shown in FIGS. 2C and 2D-1 , the primary packaging structure 130 comprises a semiconductor chip 131 and a top plastic packaging layer 134 covering the front surface of the chip 131 . The front surface of the chip 131 is provided with a plurality of metal pads. The solder bumps 132 a - 1 and 132 b - 1 are placed on the metal pads, which will be described in details later. The top plastic packaging layer 134 of the primary packaging structure 130 are only encapsulated on the side walls of the solder bumps 132 a - 1 and 132 b - 1 . A bottom metal layer 133 is formed at the back surface of the chip 131 .
[0016] The power device 100 A also comprises a bridge-shaped metal clip 150 (also shown in FIG. 2E ) attached to the bottom surface of the flipped primary packaging structure 130 or to the bottom surface of the bottom metal layer 133 of the flipped chip 131 . The bridge-shaped metal clip 150 is also attached to the third base 113 and the fourth base 114 . The bridge-shaped metal clip 150 comprises a top metal portion 151 and side metal portions 153 a and 153 b connected to two opposite sides of the top metal portion 151 . The side metal portions 153 a and 153 b are bent downwards as shown in FIG. 2C . In particular, the side metal portions 153 a and 153 b are bent away from each other, so that the angles formed between the side metal portions 153 a and 153 b and the top metal portion 151 are obtuse angles. In one embodiment, the side metal portions 153 a and 153 b are symmetrically located relative to the center of the top metal portion 151 . In addition, a groove 113 a is formed on the top surface of the third base 113 and a groove 114 a is formed on the top surface of the fourth base 114 . As a result the side metal portion 153 a can be attached and trapped in the groove 113 a, likewise the side metal portion 153 b can be attached and trapped in the groove 114 a. A conductive material 140 , such as a conductive solder or paste, is applied to bond the bottom surface of the top metal portion 151 to the bottom metal layer 133 . The groove 113 a and the groove 114 a can be of many shapes, for example, the grooves 113 a and 114 a can be in V-shape, as shown in FIG. 2C , for convenient engagement with the side metal portions 153 a and 153 b. The side metal portions 153 a and 153 b are respectively attached to the third base 113 and the fourth base 114 through conductive epoxy deposited in the groove 113 a and the groove 113 b.
[0017] Furthermore, the power device 100 A also comprises a plastic packaging body 160 encapsulating the lead frame unit, the primary packaging structure 130 and the bridge-shaped metal clip 150 . As shown in FIG. 2B where the power device 100 A is finally mounted on a PCB with the first base 111 , the second base 112 , the third base 113 and the fourth base 114 serving as electrical contacts directly connected to the pads on the PCB. Here, the respective bottom surfaces of the first base 111 , the second base 112 , the third base 113 and the fourth base 114 should be exposed from the bottom surface of the plastic packaging body 160 . Furthermore, as shown in FIG. 2B , the third base 113 and the fourth base 114 usually include a plurality of pins, for example pins 113 ′ and pins 114 ′. Therefore, the bottom surfaces of the pins 113 ′ and the pins 114 ′ are also exposed from the bottom surface of the plastic packaging body 160 and serving as the electrical contacts of the third base 113 and the fourth base 114 .
[0018] In the embodiment shown in FIGS. 2C to 2D-1 , one or more through holes 152 are formed through the whole thickness of the top metal portion 151 . FIG. 2E shows a top view of the bridge-shaped metal clip 150 including a through hole 152 . The through hole 152 can be of a ‘cross’ shape as shown in FIG. 2E or can be of round, rectangle, polygon or any other suitable shapes. The through hole 152 is used for venting gas during the reflow of the conductive material 140 that attaches the top metal portion 151 to the bottom metal layer 133 . Additionally, any excess of the conductive material 140 deposited to form a conductive layer between the top metal portion 151 and the bottom metal layer 133 can be dredged into the through holes 152 so that the final layer thickness of the conductive material 140 is uniform.
[0019] In another embodiment as shown in FIG. 2D-2 , one or more clip grooves 152 ′ can be formed from a bottom surface of the top metal portion 151 with the bottom of the clip groove 152 ′ ended up inside the top metal portion 151 . The groove 152 ′ may be of many shapes similar to the through holes 152 as described above. Similar to the though hole 152 , the clip groove 152 ′ is used for venting gas during the reflow of the conductive material 140 for attaching the top portion 151 to the bottom metal layer 133 and for holding any excess of the conductive material 140 deposited to form a conductive layer between the top metal portion 151 and the bottom metal layer 133 thus improving the thickness uniformity of the conductive material 140 .
[0020] Another difference between the embodiment of FIG. 2D-1 and that of FIG. 2D-2 is that the top surface of the top metal portion 151 as shown in FIG. 2D-1 is not exposed from the plastic packaging body 160 whereas the top surface of the top metal sheet 151 as shown in FIG. 2D-2 is exposed from the plastic packaging body 160 . To achieve a structure as shown in FIG. 2D-2 , before depositing a plastic packaging material, such as epoxy resin, to form the plastic packaging body 160 , a resist film (not shown) can be applied to the inner surface of the top chase of the molding tool, which is then brought in contact with and covers the top surface of the top metal portion 151 thus preventing it from coverage by the plastic packaging materials. The plastic packaging body 160 encapsulates the lead frame unit, the primary packaging structure 130 and the side metal portions 153 a and 153 b of the bridge-shaped metal clip 150 . After the plastic packaging material is solidified, the resist film is peeled off from the top surface of the top metal portion 151 , thus the top surface of the top metal portion 151 is now exposed from the top surface of the plastic packaging body 160 . This plastic packaging process is usually completed at a wafer processing level (i.e., this technology is used in WLCSP), which is well known in the art.
[0021] In another embodiment of the invention, recessed portions 154 a and 154 b formed on the top surface of the top metal portion 151 at the corner of the top metal portion 151 are configured to connect the side metal portions 153 a and 153 b thus forming a step structure. FIGS. 2C-2E illustrate the structure of the bridge-shaped metal clip 150 . Typically, the side metal portions 153 a and 153 b are originally formed on the same plane of the top metal portion 151 , then the side metal portions 153 a and 153 b are bent downward by an angle (through a stamping method), so that the angles formed between the side metal portions 153 a and 153 b and the top metal portion 151 are obtuse angles. However, the thus obtained final top metal portion 151 is not a flat plane and the edges of the top surface of the top metal portion 151 at the corner of the top metal portion 151 and the side metal portions 153 a 153 b do not form a straight line. Therefore, the recessed portions 154 a and 154 b at the corner of the top metal portion 151 and the side metal portions 153 a 153 b can beneficially buffer and stop the tension influences of the side metal portions 153 a and 153 b on the top metal portion 151 during the stamping step with the thus obtained top metal portion 151 free of deformation, in which case lines 151 a - 1 and 151 a - 2 at the two sides of the top surface of the top metal portion 151 are now straight lines and the top surface of the top metal portion 151 is now a flat rectangular plane.
[0022] FIGS. 3A-3F illustrate a method for preparing the primary packaging structure 130 . A wafer 1310 (shown in FIG. 3C ) usually includes numerous semiconductor chips 131 (shown in FIG. 3A ) formed at the top surface of the wafer and spaced-apart by scribe lines (not shown), which is well known in the art. The front surface of the chip 131 includes numerous metal pads 132 , such as aluminum-silicon pads, which serve as the electrodes of the chip or the terminals for off-chip signal transmission. In a preferred embodiment, the chip 131 is a vertical power metal oxide semiconductor field effect transistor (MOSFET). The metal pads 132 include metal pads 132 b forming the first electrode (such as a source electrode) of the chip 131 and a metal pad 132 a forming the second electrode (such as a gate electrode) of the chip 131 , while the drain electrode area of the chip 131 is formed at the back surface of the chip 131 (not shown). Firstly, numerous solder bumps are formed on the metal pads 132 by ball placement or plating and the likes. As shown in FIG. 3B , a solder bump 132 a - 1 is formed on the metal pad 132 a and a solder bumps 132 b - 1 are formed on the metal pads 132 b. As the area of the metal pad 132 b forming the source electrode is usually larger than that of the metal pad 132 a forming the gate electrode, the size of the solder bumps 132 b - 1 is also larger than that of the solder bumps 132 a - 1 to carry large currents. Alternatively, numerous solder balls of smaller size than the solder bump 132 b - 1 can be placed on the metal pad 132 b (not shown) and are closer to each other, so that the solder balls can be merged into one piece after being heated, softened and melted to form the solder bump 132 b - 1 of a larger size. As shown in FIG. 3C , a plastic packaging layer 1340 is formed on the front surface of the wafer 1310 covering all the solder bumps 132 a - 1 and 132 b - 1 . Then the plastic packaging layer 1340 is ground until the solder bumps 132 a - 1 and 132 b - 1 are exposed through the plastic packaging layer 1340 . As shown in FIG. 3D , the top surfaces of the solder bumps 132 a - 1 and 132 b - 1 and the top surface of the plastic packaging layer 1340 are co-planar. The plastic packaging layer 1340 physically supports the wafer 1310 . Therefore, when the wafer 1310 is ground and thinned, the wafer 1310 is not prone to crackage. This means that highly desirable ultra-thin chips with reduced substrate resistance can be made. As shown in FIG. 3E , after the back surface of the wafer 1310 is ground and thinned, impurity ions can be heavily doped into the back surface of the thinned wafer 1310 (optionally), and then a metal layer 1330 can be deposited onto the back surface of the thinned wafer 1310 forming the drain electrode at the back surface of the chip. The wafer 1310 , the plastic packaging layer 1340 and the metal layer 1330 (as shown in FIG. 3E ) are then cut apart to form individual primary packaging structures 130 (as shown in FIG. 3F ), each of which includes a single chip 131 and a top plastic packaging layer 134 covering the front surface of the chip 131 . The top plastic packaging layer 134 only covers the side walls of the solder bumps 132 a - 1 and 132 b - 1 with the top surface of the solder bumps 132 a - 1 and 132 b - 1 exposed through the top plastic packaging layer 134 and is co-planar with the top surface of the top plastic packaging layer 134 . In this step, the metal layer 1330 is also cut apart into numerous bottom metal layers 133 , each of which covers the back surface of a chip 131 and is contact with the drain area at the back surface of the chip 131 forming the third electrode (such as the drain electrode) of the chip 131 .
[0023] As shown in FIG. 2D-1 , the solder bump 132 b - 1 , formed on the metal pad 132 b forming the first electrode of the chip, is attached to the top surface of the first base 111 . As shown in FIG. 2C , the solder bump 132 a - 1 , formed on the metal pad 132 a forming the second electrode of the chip, is attached to the top surface of the second base 112 . As shown in FIG. 2B , the surface area of the first base 111 forming the source electrode is usually larger than the surface area of the second base 112 forming the gate electrode. Therefore, the exposed area of the bottom surface of the first base 111 is larger than the exposed area of the bottom surface of the second base 112 , which also performs the function of heat dissipation. The third base 113 and the fourth base 114 are electrically connected to the drain electrode of the chip 131 through the bridge-shaped metal clip 150 .
[0024] FIGS. 4A-4C illustrate a method for preparing the power device 100 A shown in FIG. 2D-1 along the line BB of FIG. 2B . However, the preparation of the power device 100 A shown in FIG. 2C along the line AA of FIG. 2B is also described but not shown in FIGS. 4A-4C . In FIG. 4A , a lead frame unit is provided firstly. The lead frame unit includes the first base 111 , the second base 112 , the third base 113 and the fourth base 114 , all of which are separated from each other, with the third base 113 and the fourth base 114 respectively arranged at the two opposite sides of the first base 111 as described above. The primary packaging structure 130 is then attached on the first base 111 and the second base 112 of the lead frame unit by a conductive epoxy. In this step, the plurality of solder bumps 132 b - 1 and 132 a - 1 (see FIG. 3F ) formed on the front surface of the primary packaging structure 130 are respectively attached to the first base 111 and the second base 112 by a conducting material, such as the conducting material 120 b shown in FIG. 4A . In FIG. 4B , the bridge-shaped metal clip 150 is mounted atop the primary packaging structure 130 . The bridge-shaped metal clip 150 comprises the top metal portion 151 and the side metal portions 153 a and 153 b connected to two opposite sides of the top metal portion 151 and bent downwards. In this step, the top metal portion 151 is directly attached to the primary packaging structure 130 . The side metal portions 153 a and 153 b are respectively aligned and positioned in the groove 113 a at the top surface of the third base 113 and the groove 114 a at the top surface of the fourth base 114 . Conductive epoxy is deposited in the groove 113 a and the groove 114 a for attaching the side metal portions 153 a and 153 b of the bridge-shaped metal sheet 150 to the third base 113 and the fourth base 114 respectively. As such, the bridge-shaped metal clip 150 is precisely located in the groove 113 a and the groove 114 a. A bottom metal layer 133 at the back surface of the primary packaging structure 130 is connected to the bottom surface of the top metal portion 151 through the conductive material 140 . In FIG. 4C , the plastic packaging material is deposited to form the plastic packaging body 160 encapsulating the lead frame unit, the primary packaging structure 130 and the bridge-shaped metal clip 150 . The bottom surfaces of the first base 111 , the second base 112 , the third base 113 and the fourth base 114 of the lead frame unit are exposed from the bottom surface of the plastic packaging body 160 , while the top surface of the top metal portion 151 can be selected whether to be exposed from the top surface of the plastic packaging body 160 or not. In FIG. 4C , the top metal portion 151 is covered by the plastic packaging body 160 and the through hole 152 in the top metal portion 151 is filled with plastic packaging material.
[0025] FIGS. 5A-5B illustrate a structure of a power device 100 B according to another embodiment of the invention. The structure of power device 100 B is mostly similar as the structure of power device 100 A excepting the structure of the bridge-shaped metal clip 150 . As shown in these figures, the top metal portion 151 does not include a through hole. Instead it includes pluralities of dimples 155 formed on the bottom surface of the top metal portion 151 .
[0026] The dimples 155 extrude from the bottom surface of the top metal portion 15 land are located between the bottom metal layer 133 and the bottom surface of the top metal portion 151 after the bridge-shaped metal clip 150 is mounted on the primary packaging structure 130 . With the dimples formed between the bottom metal layer 133 and the bottom surface of the top metal portion 151 , the thickness of the conducting material 140 is uniform. As shown in FIG. 5B , the top surface of the top metal portion 151 of the power device 100 B is not exposed from the plastic packaging body 160 . Alternatively, the top surface of the top metal portion 151 can be exposed from the top surface of the plastic packaging body 160 (not shown).
[0027] FIGS. 6A-6D illustrate a power device 100 C of another embodiment of the invention with the structure and the position of a second base of the lead frame unit different from that in the power devices 100 A and 100 B. FIGS. 6B and 6C are cross sectional schematic diagrams along the dotted lines AA and BB in FIG. 6A respectively. As shown in FIGS. 6A and 6B , the second base 212 includes a base extension 212 a and an external pin 212 b connected to the base extension 212 a. The thickness of the base extension 212 a is thinner than the thickness of the first base 111 and thus the base extension 212 a is encapsulated inside the plastic packaging body 160 . Only the bottom surface of the external pin 212 b is exposed from the bottom surface of the plastic packaging body 160 .
[0028] As shown in FIG. 6A , the length of the fourth base 214 is shorter than the length of the third base 113 and the external pin 212 b is arranged on the same side as the fourth base 214 . Particularly the external pin 212 b and a plurality of pins 214 ′ in the fourth base 214 are arranged on the same straight line. The base extension 212 a extends under the primary packaging structure 130 until the solder bump 132 a - 1 on the front surface of the primary packaging structure 130 superimposed on the base extension 212 a. As such, the conducting material 120 a is deposited for attaching the solder bumps 132 a - 1 on the top surface of the base extension 212 a. As shown in FIGS. 6B-6C , the top surface of the base extension 212 a and the top surface of the first base 111 are arranged on the same plane substantially, so that the primary packaging structure 130 is easily mounted on the first base 111 and the base extension 212 a of the second base 212 . The thickness of the base extension 212 a is thinner than the thickness of the first base 111 so that the extension base 212 a is encapsulated inside the plastic packaging body 160 to avoid any negative effect on subsequent SMI technology. The external pin 212 b and the fourth base 214 are arranged on the same straight line, therefore, to avoid a short circuit between the external pin 212 b and the bridge-shaped metal clip 150 , as shown in FIG. 6D , the bridge-shaped metal clip 150 includes a shorter side metal portion 153 ′b for connecting to the fourth base 214 without connecting to the external pin 212 b of the second base 212 . Particularly, the width D 1 of the side metal portion 153 ′b is smaller than the width D 2 of the top metal portion 151 , while the width of the side metal sheet 153 a is the same as the width D 2 of the top metal portion 151 . In the power device 100 C, the top surface of the top metal portion 151 is covered by the plastic packaging body 160 .
[0029] FIGS. 7A-7C illustrate a power device 100 D of another embodiment of the invention. The power device 100 D is similar to the power device 100 C, excepting that the top surface of the top metal portion 151 is exposed from the plastic packaging body 160 . FIG. 7C is a top view of the power device 100 D showing the top metal portion 151 is exposed from the plastic packaging body 160 , which is also used to improve the heat dissipation of the power device.
[0030] The above detailed descriptions are provided to illustrate specific embodiments of the present invention and are not intended to be limiting. Numerous modifications and variations within the scope of the present invention are possible. The present invention is defined by the appended claims. | A power semiconductor package has an ultra thin chip with front side molding to reduce substrate resistance; a lead frame unit with grooves located on both side leads provides precise positioning for connecting numerous bridge-shaped metal clips to the front side of the side leads. The bridge-shaped metal clips are provided with bridge structure and half or fully etched through holes for relieving superfluous solder during manufacturing process. | 7 |
This application relates generally to pressure extrusion, and more particularly to pressure extrusion coupled with centrifugal fiber spinning for producing continuous and nonwoven fabrics.
One of the constraints of conventional fiber extrusion is the cost and inherent limitation of the mechanical roll systems which are required to pull fibers out of spinnerets at economical speeds. In other systems, the mechanical roll system has been by-passed by using air to pull fibers out of spinnerets at high speed. The air process is difficult to control. It suffers from spinline instability and lack of fiber uniformity. In addition, the use of compressed air is very energy intensive and costly.
Known centrifugal fiber spinning systems also offer very limited utility for fiber production, especially for viscous, thermoplastic polymers, because of low productivity and poor process and product controls. In these systems, fiber forming material is fed by gravity into the interior of a rapidly rotating open cup or die. The fiber forming fluid flows by virtue of the centrifugal force to the interior wall of the cup or die from whence it is spun into fibers from the outlet passages which pass through the wall of the cup or die. The generated centrifugal energy forces the fluid to extrude through the die. The rate of extrusion is relatively low, since the outlet passages have to be relatively small to assure fiber quality and filament stability. The use of large passages to increase productivity is not suitable for fiber extrusion, however. It is mainly for this reason that centrifugal extrusion of this type offers more utility for the production of larger diameter pellets than for the production of fibers, especially when considering thermoplastic polymers.
Only those polymers which are heat resistant and relatively fluid above their melting points may have any practical use for fiber conversion by the above described known spinning process. The literature mentions polypropylene, polyester, ureaformaldehyde and glass for use in such systems. Most thermoplastic polymers are too viscous and chemically unstable at the temperature required to reduce the viscosity sufficiently for centrifugal fiber spinning by this method. This is primarily due to the fact that the molten polymer is fed into an open cup. Except for the effects of rotation, the pressure inside the cup is virtually the same as the pressure outside the cup. Accordingly, if the holes in the cup are small, the polymer will move up the side of the cup and over the rim.
The above mentioned systems are illustrated by U.S. Pat. No. 4,288,397, issued Sept. 8, 1981, U.S. Pat. No. 4,294,783, issued Oct. 13, 1981, U.S. Pat. No. 4,408,972 issued Oct. 11, 1983 and U.S. Pat. No. 4,412,964 issued Nov. 1, 1983. These patents disclose a gravity feed system using a rotating cup wherein gas flows with the melt through the holes in the cup and the fiber producing condition is caused by the centrifugal force generated by the spinning of the cup and the included gas. U.S. Pat. No. 4,277,436 issued July 7, 1981 discloses a similar device using a stream of gravity fed molten material and a spinning cup so as to extrude the filaments by means of centrifugal force only.
Accordingly, an object of this invention is to provide a pressurized rotating fiber extrusion system.
A further object of the invention is to provide a rotating fiber extrusion system which is not limited to centrifugal spinning speed for controlling the extrusion rate or fiber denier.
Another object of the invention is to provide a rotating fiber extrusion system wherein it is not necessary to reduce polymer viscosity for increasing extrusion rate to improve process economics.
Yet another object of the invention is to provide a rotating fiber extrusion system wherein extrusion rate is controlled by a pumping system independent of die rotation, extrusion temperature and melt viscosity.
A further object of this invention is to provide a rotational fiber extrusion system including take-up means for producing fabric.
Yet another object of the invention is to provide a rotational fiber extrusion system including a take-up system for providing fibrous tow and yarn.
These and other objects of the invention will be obvious from the following discussion when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of the fiber producing system of the present invention;
FIG. 2 is a sectional view taken along lines 2--2 of FIG. 1;
FIG. 3 is a sectional view taken along the lines 3-3 of FIG. 2;
FIG. 4 is a sectional view taken along the lines 4-4 of FIG. 2;
FIG. 5 is a graphical illustration of the relationship between extrusion rate, die rotation, filament orbit diameter and filament speed;
FIG. 6 is a graphical illustration of denier as a function of die rotation.
FIG. 7 illustrates a modification of FIG. 2;
FIG. 8 is a schematic illustration of a system for producing a fabric;
FIG. 9 is a schematic illustration of a system producing a stretched web of FIG. 8;
FIG. 10 is a side view of the system of FIG. 9; and
FIG. 11 is a schematic illustration of a system for producing yarn.
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a method and apparatus wherein there is provided a source of liquid fiber forming material, with said liquid fiber forming material being pumped into a die having a plurality of spinnerets about its periphery. The die is rotated at a predetermined adjustable speed, whereby the liquid is expelled from the die so as to form fibers. It is preferred that the fiber forming material be cooled as it is leaving the holes of the spinnerets during drawdown. The fibers may be used to produce fabrics, fibrous tow and yarn through appropriate collection and take-up systems. The pumping system provides a pumping action whereby a volumetric quantity of liquid is forced into the rotational system independent of viscosity or the back pressure generated by the spinnerets and the manifold system of the spinning head, thus creating positive displacement feeding. Positive displacement feeding may be accomplished by the extruder alone or with an additional pump of the type generally employed for this purpose. A rotary union is provided for positive sealing purposes during the pressure feeding of the fiber forming material into the rotating die.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings, there is schematically shown in FIG. 1 a system according to the present invention for producing fibers. The system includes an extruder 11 which extrudes fiber forming material such as liquid polymer through feed pipe 13 to a rotary union 21. A pump 14 may be located in the feed line if the pumping action provided by the extruder is not sufficiently accurate for particular operating conditions. Electrical control 12 is provided for selecting the pumping rate of extrusion and displacement of the extrudate through feed pipe 13. Rotary union 21 is attached to spindle 19. Rotary drive shaft 15 is driven by motor 16 at a speed selected by means of control 18 and passes through spindle 19 and rotary union 21 and is coupled to die 23. Die 23 has a plurality of spinnerets about its circumference so that, as it is rotated by drive shaft 15 driven by motor 16 and, as the liquid polymer extrudate is supplied through melt flow channels in shaft 15 to die 23 under positive displacement, the polymer is expelled from the spinnerets and produces fibers 25 which form an orbit as shown. When used, air currents around the die will distort the circular pattern of the fibers.
FIGS. 2-4 illustrate one embodiment of the present invention. FIG. 2 is a cross-sectional view taken through spindle 19, rotary unit 21, die 23 and drive shaft 15 of FIG. 1. FIGS. 3 and 4 are cross sectional views taken along lines 3--3 and 4--4 of FIG. 2 respectively. Bearings 31 and 33 are maintained within the spindle by bearing retainer 34, lock nut 35 and cylinder 36. These bearings retain rotating shaft 15. Rotating shaft 15 has two melt flow channels 41 and 43. Surrounding the shaft adjacent the melt flow channels is a stationary part of rotary union 21. Extrudate feed channel 47 is connected to feed pipe 13, FIG. 1, and passes through rotary union 21 and terminates in an inner circumferential groove 49. Groove 49 mates with individual feed channels 50 and 52, FIG. 3, which interconnect groove 49 with melt flow channels 41 and 43.
The rotary union may be sealed by means such as carbon seals 51 and 53 which are maintained in place by means such as carbon seal retainers 54,56. Adjacent lower carbon seal 53 is a pressure adjustable nut 55 which, by rotation, may move the two carbon seal assemblies upwardly or downwardly. This movement causes an opposite reaction from belleville washers 59 and 60 so as to spring-load each sliding carbon seal assembly individually against the rotary unit.
Lower washer 60 rests on spacer 61 which in turn rests on die 23. Die 23 has a plurality of replaceable spinnerets 67 which are interconnected with flow channels such as flow channel 41 by means of feed channel 69 and shaft port 71 which extends through shaft 15 between channel 41 and circumferential groove 70, FIG. 4 so as to provide a constant source of extrudate. The apparatus is secured in place by means such as plate 73 secured to shaft 15.
If desired, a means for cooling the extrudate as it leaves the spinnerets may be provided, such as stationary ring 77 having outlet ports which pass air under pressure in the direction of arrows A. Ring 77 is secured in the position shown by support structure, not shown.
Further, electrical heaters 20 and 22, FIG. 3, are preferably provided in the stationary segment of rotary union 21 so as to maintain extrudate temperature.
As can be seen, the apparatus as described provides a system which is closed between the extruder and the die with the liquid extrudate being extruded through a rotary union surrounding the rotating shaft. Accordingly, as the shaft is rotated, the liquid extrudate is pumped downwardly through the melt flow channels in the rotating shaft and into the center of the circular die. The die, having a plurality of spinnerets 67, FIG. 4, about the circumference thereof, will cause a drawdown of the discharging extrudate when rotated by expelling the extrudate from the spinneret so as to form fibers 25 as schematically illustrated in FIG. 1. Die rotation therefore, is essential for drawdown and fiber formation, but it does not control extrusion rate through the die. The extrusion rate through the die is controlled by the pumping action of extruder 11 and/or pump 14.
In order to provide a long lasting high pressure seal between rotary union 21 and die 23, shaft 15 includes helical grooves 101 and 103 about its circumference on opposite sides of feed channels 50 and 52. Helical grooves 101 and 103 have opposite pitch so that, as the shaft is rotated in the direction as indicated by the arrow, any extrudate leaking between the mating surfaces of shaft 15 and rotary union 21, will be driven back into groove 49 and associated channels 50 and 52. Accordingly, leakage is substantially eliminated even under high pressure through the use of this dynamic seal.
The major variable involved in this system, besides the choice of polymer, are the pumping rate of the liquid polymer from the extruder and/or pump, the temperature of the polymer and the speed of rotation of the die. Of course, various size orifices may be used in the interchangeable spinnerets for controlling fiber formation without affecting extrusion rate. The rate of extrusion from the die, such as grams per minute per hole, is exclusively controlled by the amount of the extrudate being pumped into the system by the extruder and/or pump.
When the system is in operation, fibers are expelled from the circumference of the die and assume a helical orbit as they begin to fall below the rotating die. While the fibers are moving at a speed dependent upon the speed of rotation of the die as they are drawn down, by the time they reach the outer diameter of the orbit, they are not moving circumferentially, but are merely being laid down in that particular orbit basically one on top of the other. The orbit may change depending upon variation of rotational speed, extrudate input, temperature, etc. External forces such as electrostatic or air pressure may be employed to deform the orbit and, therefore, deflect the fibers into different patterns.
FIGS. 5 and 6 are derived from the following data.
TABLE 1__________________________________________________________________________DENIER VERSUS PROCESS CONDITIONSEXTRUSION FIL. ORBITRATE DIE ROTATION DIAMETER FIL. SPEED FILAMENT(g/min/hole) (r.p.m.) (INCHES) M/MIN DENIER__________________________________________________________________________1.9 500 16 640 272.0 1,000 14 1,120 162.0 1,500 15 1,800 102.1 2,000 14.5 2,300 82.1 3,000 15 3,600 53* 1,000 16 1,300 213* 1,500 19.5 2,300 123* 2,000 20.5 3,300 83* 2,500 21.5 4,300 63.8 1,000 19.0 1,500 23 3.8* 3,000 24.5 5,900 6__________________________________________________________________________ *Extrusion rate was extrapolated from screw r.p.m. Note: Line speed = orbit circumference × die rotation Denier is based on line speed and extrusion rate
FIG. 5 illustrates the relationship of the various parameters of the system for a specific polymer (Example I below) which includes the controlling parameters, pumping rate and die rotation, and their affect on filament spinning speed and filament orbit diameter. In the graph of FIG. 5, there are illustrated three different pumping rates of extrudate, which controls the extrusion rate from the die, in grams per minute per hole. In the illustration, the number inside the symbols indicates averaged pumping rate from which the graph was developed. In FIG. 6, the graph illustrates denier as a function of die rotation. As can be seen from the graphs, as the die rotational speed is increased, the filament speed and drawdown is also increased.
It is to be understood that the following examples are illustrative only and do not limit the scope of the invention.
EXAMPLE-I
Polypropylene resin, Hercules type PC-973, was extruded at constant, predetermined extrusion rates into and through a rotary union, passages of the rotating shaft, the manifold system of the die and the spinnerets. Except for the extruder, the apparatus is as shown in the cross-section of FIG. 2.
Upon extrusion, the centrifugal energy, acting on the molten extrudate causes it to draw down into fibers. The fibers form circular orbits which are larger than the diameter of the die. A stationary circular air quench ring, located above the die, as shown in FIG. 2, including orifices designed so as to direct the air downwardly and outwardly relative to the perimeter of the die, deflects the fibers at an angle of substantially 45 degrees below the plane of the die. In this example, process parameters are varied and the resultant fibers collected for testing.
1. Equipment
______________________________________a. Extrusion set-up: as shown in FIG. 1b. Extruder:Diameter, inches: 1.0Temperature Zones: 3.0Length/diameter, inches: 24/1Drive, Hp: 1.0c. Extrusion head: see FIG. 2d. Die:Diameter, inches: 6.0Number of spinnerets: 16.0Spinneret hole diameter, inches: 0.020e. Quench and Fiber Removal: circular ringRing diameter, inches: 8.0Orifice spacing, inches 1.0 angled 45° down- wardly and outwardly of the perimeter of the die______________________________________
2. Process Conditions
______________________________________a. Extrusion conditionsExtruder temperature, ° F.: Zone-1 350 Zone-2 400 Zone-3 450 Adapter 450 Rot. Union 450 Die 550-600Screw rotation, r.p.m.: set for a given extrusion rateExtrusion pressure, p.s.i.: 200-400b. Die rotation, r.p.m.: 500-3000 (See table below)c. Air quench pressure, p.s.i.: 10-30 (See table below)______________________________________
3. Data and Results
______________________________________ FiberExtrusion Die Fiber Orbit Spinning FiberRate Rotation Diameter Speed Denier(g/min/hole) (r.p.m.) (inches) (meter/min) (g/9000 m)______________________________________1.9 500 16 640 272.0 1,000 14 1,120 162.0 1,500 15 1,800 102.1 2,000 14.5 2,300 82.1 3,000 15 3,600 53.0 1,000 16 1,300 213.0 1,500 19.5 2,300 123.0 2,000 20.5 3,300 83.0 2,500 21.5 4,300 63.8 1,000 19 1,500 233.8 3,000 24.5 5,900 6______________________________________
4. Extrusion Conditions
Note:
(a) Fiber orbit diamter was measured visually with an inch-ruler.
(b) Fiber spinning speed was calculated (speed=orbit circumference x rotation).
(c) Denier was calculated, based on extrusion rate and fiber spinning speed in the well known manner.
According to the results of this experiment, the fibers become smaller with increasing die rotation, Furthermore, increasing extrusion rate, at a given die rotation, increases filament orbit and, therefore, decreases the rate of increase of filament denier.
EXAMPLE II
In the apparatus described in Example I, a polyethylene methacrylic copolymer (DuPont Ionomer resin type Surlyn-1601) was extruded. Fibers of various deniers were produced at different die rotations.
Process Conditions
______________________________________a. Extrusion conditions Temperature Zone-1 300 Zone-2 350 Zone-3 400 Adapt. 400 Rot. Union 400 Die 500-550 Screw rotation, r.p.m.: 10 Screw pressure, p.s.i.: 100-200b. Die rotation, r.p.m.: 1000, 2000, 3000c. Air quench pressure, p.s.i.: 10-30______________________________________
In another variation of this example, fibers were collected on the surface of a moving screen. The screen was moved horizontally, four inches below the plane of the die. Upon contact of the fibers with each other, the fibers were bonded to each other at the point of contact. The resultant product is a nonwoven fabric. The fabric was then placed between a sheet of polyurethane foam and a polyester fabric. Heat and pressure was then applied through the polyester fabric. The lower melting ionomer fabric was caused to melt and bond the two substrates into a composite fabric.
EXAMPLE III
In the apparatus of Example I, the following polymers which are listed in the table below, have been converted into fibers and fabrics.
Polymers Converted into Fibers and Fabrics
______________________________________ Extrusion DiePolymer Temp. ° F. Temp. ° F.______________________________________Polypropylene Amoco CR-34 400-500 550-625Polyioner Surlyn 1601 350-400 450-550Nylon terpolymer Henkel 6309 280-300 350-400Polyurethane Estane 58122 350-400 450-400Polypropylene- 400-500 550-600ethylene copolymer______________________________________
Spunbonded fabrics are produced by allowing the freshly formed fibers to contact each other while depositing on a hard surface. The fibers adhere to each other at their contact points thus forming a continuous fabric. The fabric will conform to the shape of the collection surface. In this example, fibers were deposited on the surface of a solid mandrel comprising an inverted bucket. The dimensions of this mandrel are as follows.
______________________________________Bottom diameter, inches: 7.0Top diameter, inches: 8.25Height of mandrel, inches: 7.0______________________________________
EXAMPLE IV
Nylon-6 polymer, 2.6-relative viscosity (measured in sulfuric acid), was converted into low-denier textile fibers and spun-bonded continuously into a nonwoven fabric. The fabric was formed according to the apparatus of FIG. 8. The extrusion head employed is illustrated in the cross section of FIG. 7. The fabric produced in this system is very uniform and even, with good balance in physical properties.
Equipment and Set-up
______________________________________Set-Up FIG. 8______________________________________a. Extruder One-inch diameter, One Hp driveb. Extrusion head FIG. 7 Stationary shaft, rotating die grooves are in the outside member of the rotary unionc. Die, diameter, inches 12.0 numbers of spinnerets 16 spinning holes per 1 (0.020 in. diameter) spinneretd. Quench ring, diameter, 14.0 inches______________________________________ orifices: 0.06 inches diameter at 1" spacing, angled 45 degrees downwardl and outwardly
Process Conditions
______________________________________Extrusion Temperature, °F. Z-1: 480° F. Z-2: 670° F. Z-3: 620° F. Adapter: 550° F. Melt Tube: 600 Die heaters 13 ampExtruder screw rotation, r.p.m. 33.0Die rotation, r.p.m. 2530.Air-quench pressure, psi 30.Winder speed, ft/min 10.______________________________________
Product
______________________________________ 2-ply, lay-flat fabric______________________________________Width, inches 35.Basis Weight oz/yd.sup.2 0.75______________________________________
The hole diameter of the spinneret is preferably between 0.008" and 0.030 inches with the length-to-diameter ratio being between 1:1 and 7:1. This ratio relates to desired pressure drop in the spinneret.
Shaped, tubular articles were formed by collecting fibers on the outside surface of a mandrel. The mandrel used in this experiment was a cone-shaped, inverted bucket. The mandrel was placed concentric with, and below a revolving, 6-inch diameter die. The centrifugal action of the die and the conveying action of the air quench system caused fibers to be deposited on the surface of the mandrel (bucket), thus forming a shaped textile article. The resultant product resembles a tubular filter element and a textile cap.
In another experiment, a flat plate was placed below the rotating die. The flat plate was slowly withdrawn in a continuous motion thereby producing a continuous, flat fabric.
The air quench with its individual air streams causes fiber deflection and fiber entanglement, thereby producing an interwoven fabric with increased integrity.
Copolymer and Polymer Blends
Virtually every polymer, copolymer and polymer blend which can be converted into fibers by conventional processing can also be converted into fibers by centrifugal spinning. Examples of polymer systems are given below:
Polyolefin polymers and copolymers;
Thermoplastic polyurethane polymers and copolymers;
Polyesters, such as polyethylene and polybutylene terephthalate;
Nylons;
Polyionomers;
Polyacrylates;
Polybutadienes and copolymers;
Hot melt adhesive polymer systems;
Reactive polymers.
EXAMPLE V
In the apparatus of Example IV, thermoplastic polyurethane polymer, Estane 58409 was extruded into fibers, collected on an annular plate and withdrawn continuously as a bonded non-woven fabric. Very fine textile fibers were produced at high die rotation without evidence of polymer degradation.
Process conditions
Extrusion Temperatures, °F.
______________________________________Z-1: 260Z-2: 330Z-3: 350Adapter 350Melt tube 250Die (7 amps) 450-500Quench air pressure 20 psiDie rotation, r.p.m. 2,000.00Extruder-Screw rotation, r.p.m. 12.0______________________________________
Process Parameters Controlling Fiber Production
As will be evident from the above illustrations, three major criteria govern the control of fiber formation from thermoplastic polymers with the present system:
1. Spinneret hole design and dimension will affect the process and fiber properties as follows:
a. control drawdown for a given denier
b. govern extrudate quality (melt fracture)
c. affect the pressure drop across the spinnerets
d. fiber quality and strength and fiber processability (in-line stretching and post-stretching propensity)
e. process stability (line speed potential, productivity, stretch, etc.).
2. Extrustion rate, which is governed by pumping rate of the extruder and/or additional pumping means, will affect
a. fiber denier
b. productivity
c. process stability
3. Die rotation, which controls filament spinning speed influences and controls
a. drawdown
b. spinline stability
c. denier
d. productivity for a given denier
It should be noted that temperature controls process stability for the particular polymer used. The temperature must be sufficiently high so as to enable drawdown, but not so high as to allow excessive thermal degradation of the polymer.
In the conventional non-centrifugal fiber extrusion process and in the centrifugal process of this invention, all three variables are independently controllable. However, in the known centrifugal process discussed above these variables are interdependent. Some of this interdependency is illustrated below.
1. Spinneret hole design will affect extrusion rate since it determines part of the backpressure of the system.
2. Extrusion rate is affected by die rotation, the pressure drop across the manifold system, the spinneret size, polymer molecular weight, extrusion temperature, etc.
3. Filament speed will depend on the denier desired and all of the beforementioned conditions, especially die rotation and speed.
Thus, it can be seen that the system of the present invention provides controls whereby various deniers can be attained simply by varying die rotation and/or changing the pumping rate.
It will be apparent from the above disclosure that since the extrudate is being pumped into the system at a controlled rate, the total weight of the extruded fibers can be increased by increasing the amount of extrudate being pumped into the system. Additionally, the consistency and control of fiber production is much greater than that for fibers which are extruded depending solely upon centifugal force to drive the extrudate through the holes in the wall of a cup as described in the patents cited hereinabove.
The fibers may be used by themselves or they may be collected for various purposes as will be discussed hereinafter.
FIG. 7 discloses a modified system similar to FIG. 1 wherein the central shaft remains stationary and the die is driven by external means so that it rotates about the shaft. The actual driving motor is not shown although the driving mechanism is clearly illustrated.
Non-rotatable shaft 181 includes extrudate melt flow channel 105 therethrough which interconnects with feed pipe 13 of FIG. 1. There is also provided a utility channels 102 and 104 which may be used for maintaining electrical heating elements (not shown). Shaft 101 is supported and aligned at its upper end by support plate 107 and is secured thereto by bolt 106 and extends downwardly therefrom.
Cylindrical inner member 111 is secured and aligned to plate 107 by means such as bolt 112. At its lower end, inner member 111 has secured thereto a flat annular retainer plate 114 by means of a further bolt. Plate 114 supports outer member 115 of the spindle assembly and has bearings 121 and 123 associated therewith. Onto the lower end of outer member 115 is bolted an annular plate 150 by means of bolts such as 151. A thin-walled tube 152 is welded on the inside wall of member 150. The three interconnected members 152, 150, and 115 form an annular vessel containing bearings 121 and 123 and oil for lubrication. The entire vessel is rotated by drive pulley 113 which is driven by belt 116 and is secured to outer member 115 by means such as bolt 118. The rotating assembly is connected to die 141 by means of adapter 120 and rotates therewith.
Bushing 125 surrounds shaft 101 and supports graphite seals 129a and 129b and springs 130 and 131 on either side thereof. Sleeves 126 and 128 are secured to the die by screws 153 and 154 and rotate with die 141. The inside surfaces of the sleeves include integral grooves 137 and 139 which extend above and below melt flow channel 143 so as to drive any liquid extrudate leaking along the sleeves towards channel 143 in the same manner as is described in connection with the grooves on the rotating shaft of FIG. 2.
The die 141 is bolted onto the adapter 120 via bolts such as bolt 155. Each melt flow channel, such as 143, contains replaceable spinneret 145 with melt spinning hole 156. Melt flow channel 143 terminate at their inner ends with melt flow channels 105. The die is heated with two ring heaters 157 and 158 which are electrically connected to a pair of slip rings 159 and 160 by means not shown. Power is introduced through brushes 161 and 162 and regulated by a variable voltage controller (not shown).
FIG. 8 is a schematic illustration of an assembly using the present invention to form fabrics.
Unistrut legs 201, support base frame 203 which in turn supports extruder 205. Extruder 205 feeds into adapter 207 and passes downwardly to die 215. Motor 209 drives belt 211 which in turn rotates the assembly as described in FIG. 7. Stationary quench ring 213 of the type shown in FIG. 2 surrounds the die as previously discussed so as to provide an air quench for the fibers as they are extruded. A web forming plate 219 is supported beneath the base support frame and includes a central aperture 221 which is of a larger diameter than the outside diameter of the rotating die.
As the die is rotated and the fibers are extruded, they pass beyond aperture 221 and strike plate 219. Fibers are bonded during contact with each other and plate 219, thus producing nonwoven fabric 225 which is then drawn back through aperture 221 as tubular fabric 225. Stationary spreader 220 supported below the die, spreads the fabric into a flat two-ply composite which is collected by pull roll and winder 227. Thus, the fabric which is formed as a result of the illustrated operation may be collected in a continuous manner.
FIGS. 9 and 10 are schematic representations of a plan and side view of a web forming system using the present invention.
The frame structure and extruder and motor drive are the same as described in connection with FIG. 8. The die is substantially the same as in FIG. 8 and includes therewith the quench ring 213.
In the web forming system, mandrel 235 is added below and substantially adjacent die 215. As can be seen, mandrel 235 is substantially domed shaped with a cut out portion to accommodate continuous belts 237 and 239 which constitute a spreader. As the fibers leave die 215 in an orbit fashion, they drop downwardly onto the mandrel and are picked up and spread by continuous belts 237 and 239.
Nip roll 243 is located below belts 237 and 239 and draws web 241 downwardly as it passes over the spreader, thus creating a layered web.
Layered web 249 then passes over pull roll 245 and 247 and may be stored on a roll (not shown) in a standard fashion.
FIG. 11 is a schematic of a yarn and tow forming system using the present invention.
Frame 300 supports extruder 301, drive motor 302 and extrusion head 303 in a manner similar to that discussed in connection with FIG. 8. Radial air aspirator 304 is located around die 305 and is connected to air blower 306. Both are attached to frame 300. In operation, fibers are thrown from the die by centrifugal action into the channel provided by aspirator 304. The air drag created by the high velocity air causes the fibers to be drawndown from the rotating die and also to be stretched. The fibers are then discharged into perforated funnel 308 by being blown out of aspirator 304. The fibers are then caused to converge into a tow 309 while being pulled through the funnel by nip rolls 310. Tow 309 may then be stuffed by nip rolls 311 into crimper 312 and crimped inside of stuffing box 313, producing crimped tow 314. The crimped tow is then conveyed over rolls 315 and continuously packaged on winder 316.
The above description, examples and drawings are illustrative only since modifications could be made without departing from the invention, the scope of which is to be limited only by the following claims. | An apparatus wherein there is provided a source of fiber forming material, with said fiber forming material being pumped into a die having a plurality of spinnerets about its periphery. The die is rotated at a predetermined adjustable speed, whereby the liquid is expelled from the die so as to form fibers. It is preferred that the fiber forming material be cooled as it is leaving the holes in the spinnerets during drawdown. The fibers may be used to produce fabrics, fibrous tow and yarn through appropriate take-up systems. The pumping system provides a pumping action whereby a volumetric quantity of liquid is forced into the rotational system independent of viscosity or the back pressure generated by the spinnerets and the manifold system of the spinning head, thus creating positive displacement feeding. Positive displacement feeding may be accomplished by the extruder alone or with an additional pump of the type generally employed for this purpose. A rotary union is provided for positive sealing purposes during the pressure feeding of the fiber forming material into the rotating die. | 3 |
.Iadd.CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application PCT/NL92/00171, filed Oct. 1, 1992, now abandoned..Iaddend.
BACKGROUND OF THE INVENTION
The present invention relates to a method of automatically cleaning teat cups in an implement for milking animals, such as cows. For hygienic reasons because of quality requirements imposed on milk, effective cleaning the teat cups is important. It is especially important for dirt to be removed from the exterior of the teat cups and more particularly from the upper sides thereof, since these sides come into contact with the udders of the animals.
SUMMARY OF THE INVENTION
According to the invention, the method of cleaning teat cups in an implement for milking animals, such as cows, is characterized in that, after milking an animal, the teat cups are removed from the animal's teats and cleaned automatically with a cleaning device. Since the teat cups can easily be contaminated by each cow, a rinsing liquid is discharged across the upper side of the teat cups. In other words, cleaning the exterior of the teat cups at the upper side is effected after each milking run. To clean the interior of the teat cups and the milking lines connected thereto a different method is used. According to the invention, if after milking an animal the milking parlor is not then entered by another animal to be milked, a rinsing liquid is flushed through the teat cups and the milking lines connected thereto. Bacterial action is prevented by flushing before milk remaining in the teat cups and lines connected thereto has dried. The rate of drying depends upon the outside temperature. In any case, it is desirable to flush the teat cups and the lines connected thereto every time the milking parlor is not entered by another animal to be milked within a predetermined period of time. This predetermined period of time is preferably in the order of five minutes but may be as long as about an hour after a previous animal has been milked. In a particular method in accordance with the invention, the rinsing liquid is passed via separate channels over the upper side of the teat cups and into the teat cups with the milking lines connected thereto, respectively. This makes it possible to rinse the exterior of the teat cups independently of the cleaning of their interiors which receive the animals' teats and the milking lines connected thereto.
When milking, milk from the animals is conveyed from the teat cups and the milking lines connected thereto to a milk tank. A three-way valve is incorporated in an advantageously selected location in the milking lines. The three-way valve allows the milk conduit between a teat cup and the milk tank to be interrupted so that fluid flowing therein is diverted to a liquid material reservoir. It is then possible to circulate rinsing liquid received in this liquid material reservoir to the spray nozzles and from there through the teat cups which have been incorporated in the rinsing liquid circuit, next through the relevant milking lines connected thereto, and finally through the said three-way valve back to the liquid material reservoir. Thus, the teat cups and the milk lines connected thereto are flushed, and the residual milk in the teat cups and in the milk lines connected thereto is removed. Such a combined rinsing line and milk line system is disclosed in European Patent Application No. 0 385 539 of van der Lely, published Sep. 5, 1990.
The invention not only relates to a method of cleaning teat cups but also relates to an apparatus for milking animals which provides a cleaning device for teat cups. The method in accordance with the invention can be applied with the cleaning device disclosed herein. This apparatus is provided with a rinsing liquid circuit that includes spray nozzles. The end of a teat cup, which is incorporated in the rinsing liquid circuit, is adapted for receiving the spray nozzles. Each of the spray nozzles has one or more of flow-out apertures, through which a rinsing liquid is conducted over the upper sides of the teat cups connected thereto.
An important feature is that not only are the exterior upper sides of the cups cleaned, inasmuch as these upper sides come into contact with the animal's udder, but the interior surfaces that contact the animals' teats are also cleaned. According to the invention, the implement is therefore characterized in that each of the spray nozzles of the cleaning device is provided with one or more first flow-out apertures, through which rinsing liquid from the spray nozzles is discharged into the teat cups connected to the spray nozzles. A second flow-out aperture is provided, through which rinsing liquid is discharged over the upper surface of the teat cups connected thereto. In a preferred embodiment, separate ducts have been provided in the spray nozzles for rinsing liquid from different sources to be received through the first and second flow-out apertures. This makes it possible to rinse the interiors of the teat cups independently of cleaning their exteriors and, more specifically, independently of cleaning of the upper surfaces of the teat cups. In addition, it is possible to apply different pressures to discharge the rinsing liquid through the separate flow-out apertures. The second flow-out aperture is preferably annular to effect an adequate cleaning of the upper side of a teat cup. In this situation, the second flow-out aperture is more particularly located in a plane perpendicular to the longitudinal axis of a spray nozzle and teat cup connected thereto. In a preferred embodiment, the second flow-out aperture is disposed in the spray nozzle so that, when a vacuum is applied in a connected teat cup in order to effect a connection with and cause the teat cup to move upwardly relative to the spray nozzle, the second flow-out aperture is closed, assuming at least no liquid pressure is present in the duct leading to this flow-out aperture. The first flow-out apertures can then be arranged in a spray nozzle so that, when a teat cup is connected thereto, the first flow-out apertures are located directly below the upper edge of the teat cup. In a preferred embodiment, the spacing between the first and the second flow-out apertures is approximately five to ten millimeters.
In a further preferred embodiment according to the invention, the cleaning device of the apparatus is provided with a carrier element, to which the spray nozzles are connected. In accordance with another feature of the invention, the carrier element has ducts through which rinsing liquids are introduced into the spray nozzles. According to yet another feature of the invention, the carrier element has a first duct system through which the rinsing liquid from one source flows to the first flow-out apertures of the spray nozzles and a second duct system through which the rinsing liquid from a different source flows to the second flow-out apertures of the spray nozzles. Consequentially, only two supply lines for rinsing liquid needs be connected to the device and it is not necessary for each of the flow-out apertures of the spray nozzles have a separate supply line whereby a highly compact construction for the cleaning device is possible. A screen can be provided around the cleaning device or around the individual spray nozzles in a manner to cover the upper ends of the connected teat cups thereby preventing the rinsing liquid from being discharged beyond the upper surfaces of teat cups connected thereto if sprayed excessively from the second flow-out aperture connected thereto in lateral directions.
Rinsing the teat cups is especially important during the automated milking of animals. In accordance with a further feature of the invention, the cleaning device is connected to a milking robot which forms part of the implement for milking animals. The cleaning device may then be secured to the milking robot in such a position that, when the milking robot is not operative for milking, the teat cups mounted on a robot arm forming part of the milking robot, can be connected to the cleaning device by an upward movement of the robot arm.
In another embodiment according to the invention, the apparatus is provided with a cleaning member for cleaning the teats of an animal to be milked and thus the apparatus has a multi-functional character, since it can clean both the teat cups and the animal's teats. According to a further feature of the invention, the apparatus includes a cleaning system for cleaning the cleaning member. Using the cleaning system, it is possible, after cleaning the teats of the animal by the cleaning member, to clean the cleaning member itself, so that the next animal to be milked will be cleaned by the cleaning member under highly hygienic conditions. Operating under these conditions contributes to a relatively low somatic cell count of the milk and to an extremely low risk of infection by, for example, mastitis between the animals.
In accordance with a yet further feature of the invention, the cleaning system comprises a box-like housing having a slot, through which the cleaning elements of the cleaning member are inserted. After completion of cleaning the teats, the cleaning elements are stored in the box-like housing. In accordance with a still further feature of the invention, the box-like housing contains one or a plurality of rinsing members. The rinsing member introduces rinsing liquid into the box-like housing, as well as to one or a plurality of brushes. During cleaning of the cleaning elements in the box-like housing, rinsing liquid is sprayed against the cleaning elements, while at the same time the cleaning elements rotate against the brushes.
In order to effect a proper positioning of the cleaning device and the cleaning member in the box-like housing, the box-like housing is provided with a positioning mechanism which also serves as a retention element. The positioning mechanism provides that the cleaning device and cleaning member are brought into and maintained in a pre-determined position relative to the box-like housing each time they are stored therein. Thus, when applied to a milking robot, the positions of the cleaning device and cleaning member are relatively simple to define, so that an arm of the milking robot is able to retrace the paths of the cleaning device and cleaning member to the same positions on each occasion of use.
The apparatus may include a milking parlor having on at least one of its longitudinal sides a fixed frame including a first, upper frame portion to which is attached a milking robot for the automatic milking of animals. It may also include a second, lower frame portion, against which the milking robot bears and along the underside of which the milking robot's arms are positioned under the animal in the milking parlor. Furthermore, the milking robot may include a carrier frame for further parts of the milking robot, the carrier frame being movable along the upper frame portion. In this manner, the cleaning device may be secured to the carrier frame of the milking robot. More specifically, the further parts of the milking robot may include a robot arm, on which teat cups are mounted. The cleaning device or cleaning members are connected to the carrier frame so that, when the milking robot is not operative for milking, the teat cups can be caused to engage cleaning device by an upward movement. Consequently according to a still further feature of the invention, the mutual spacing between the teat cups corresponds to that between the spray nozzles of the cleaning device.
In a preferred embodiment according to the invention, the robot arm includes an after-treatment device for treating the udder and/or the teats of an animal after milking.
More specifically, the invention also relates to an apparatus for automatically milking animals, such as cows, which includes an after-treatment device for automatically destroying, neutralizing or inhibiting the growth of pathogenic microorganisms on the udder and/or the teats of a milked animal to reduce the likelihood that the animal will become infected. The after treatment device includes a spray nozzle, the supply line thereto containing a valve near the spray nozzle. As a result, on opening of the valve, the occurrence of initial and final phenomena relating to the commencement of termination of the liquid supply to the spray nozzle is prevented, so that almost immediately after the valve has been opened a preferably fan-shaped spray pattern is produced by the spray nozzle. In a preferred embodiment according to the invention, the spray nozzle is arranged at the outer end of a milking robot between two teat cups at the end of the robot arm. Thus after the automatic milking, the animal's udder and/or teats can be disinfected without human intervention.
According to a still further feature of the invention, the spray nozzle is arranged at or near the end of an arm of a milking robot for the automatic milking of animals so that, relative to such end, a forwardly and upwardly directed fan-shaped spray pattern is provided. According to a yet further feature of the invention, this fan-shaped pattern extends at an angle in the range between ten and fifty degrees relative to a vertical plane through the front teat cups. Because the fan-shaped pattern is directed forwardly and upwardly, liquid is prevented from falling into the teat cups during the spraying of the udder and/or the teats.
The invention, furthermore relates to a method of after-treatment of the milked animal's teats in an apparatus for the automatic milking of animals. After the animal has been milked, the teat cups are disconnected from the animal's teats and an after-treatment liquid is sprayed automatically against the udder and/or the teats. Thus, after each milking run, without human intervention, the udder and/or the teats of the milked animal are disinfected automatically. This is beneficial to the animal's hygiene and health. The invention also relates to a method wherein the after-treatment liquid is sprayed in a fan-shaped pattern while being moved along under the udder in a direction corresponding to that extending from the plane of the fan-shaped pattern to the teat cups. By thus treating the udder and/or teats with the after-treatment liquid, such liquid does not drip into the teat cups because they are moving away from the sprayed surfaces.
The invention not only relates to an apparatus for milking animals which is provided with a cleaning device as described in the present application, but also relates to a cleaning device as applied by this implement and/or as applied in a method disclosed in the present application.
For a better understanding of the invention and to show how the same may be carried into effect, reference is now made, by way of example, to the embodiments shown in the accompanying drawings:
BRIEF DESCRIPTIONS OF THE DRAWINGS
FIG. 1 is a side elevational view of an apparatus for automatic milking of animals, in which the cleaning device of the invention is incorporated;
FIG. 2 is a plan view of a portion of the apparatus including the cleaning device shown in FIG. 1;
FIG. 3 is a side elevational view of the spray nozzles of the cleaning device in accordance with the invention;
FIG. 4 is a cross-sectional view of a spray nozzle connected to the upper part of a teat cup;
FIG. 5 is a side elevational view of an alternative cleaning device with spray nozzles in accordance with the invention;
FIG. 6 is a sectional view of a portion of the alternative cleaning device taken on line VI--VI in FIG. 5;
FIG. 7 is a cross-sectional view of a portion of the alternative cleaning device and a spray nozzle taken on line VII--VII in FIG. 5;
FIG. 8 is a sectional view of a portion of the alternative cleaning device taken on line VIII--VIII of FIG. 5;
FIG. 9 is a plan view of an alterative embodiment of the cleaning device similar to FIG. 5;
FIG. 10 is a side elevational view of an alternative embodiment of an apparatus according to the invention, which is provided with a cleaning device as well as with a cleaning member for cleaning the teats or the udder or both of an animal to be milked;
FIG. 11 is an end elevational view of the embodiment of FIG. 10, located on the robot arm of the implement of FIG. 1, as well as cleaning means for cleaning the cleaning member in FIG. 10;
FIG. 12 is a plan view of the embodiment illustrated in FIG. 11;
FIG. 13 is a side view as seen in the direction of arrow XIII of a portion of the embodiment shown in FIG. 12;
FIG. 14 is a cross-sectional view taken on line XIV--XIV in FIG. 13;
FIG. 15 is a plan view of the embodiment shown in FIG. 13;
FIG. 16 is a diagram of an after-treatment apparatus for after-treatment of the udder and/or the teats after the milking of an animal, it being indicated schematically how the apparatus is connected; and
FIG. 17 is a side elevational sectional view of an after-treatment apparatus according to FIG. 16 incorporated in the embodiment of FIG. 12, to an enlarged scale, taken on line XVII--XVII in FIG. 12;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus illustrated in FIGS. 1 and 2 includes a milking parlor 1 surrounded by a railing 2 which allows an animal in parlor 1 a limited freedom of movement. The animal can enter the milking parlor from the lateral side at the rear and leave from the forward side. The front of the milking parlor is provided with a feeding plant, and the cow upon advancing sufficiently far within the parlor to the feeding plant is in a position to be easily milked. At a longitudinal side of the milking parlor, in contrast to wherein the entrance and exit are located, is a fixed frame 3 which forms parts of railing 2. Fixed frame 3 includes a first frame portion 4 and a second frame portion 5. First frame portion 4 extends parallel to and is located predominantly over second frame portions 5. In this configuration, first frame portion 4 is rigidly connected to the exterior side of two vertical posts 6 and 7 which form part of railing 2 wherein second frame portion 5 is rigidly fitted between these two posts 6 and 7. A milking robot designated generally by reference numeral 8 for the automatic milking of animals is movably connected to first frame portion 4. This milking robot bears against second frame portion 5, which is provided at a height whereby arms of milking robot 8 can be moved along its underside to under the cow present in the milking parlor. Milking robot 8 includes a carrier frame 9 for additional portions of the milking robot. By using upper frame portion 4 as a rail, carrier frame 9 and consequently the entire milking robot 8 is easily moved along this frame portion. Carrier frame 9 includes a horizontal beam 10 which extends substantially parallel to first frame portion 4. A pillar 11 extends perpendicular to carrier frame 9 in a vertical downward direction and is rigidly secured thereto with two struts 12. Pairs of supporting elements 13 are located near the ends of beam 10. Connected to each pair of supporting elements 13 at an angle of approximately 45°, with the aid of supporting plates rigidly connected thereto, are two rollers 16 forming a roller element pair 15. Roller element pair 15 is arranged so that carrier frame 9 is suspended from upper frame portion 4 wherein it is easily movable therealong. Two carriers 17 are provided at either side of the beam 10 of carrier frame 9. A motor 19 is attached to these carriers wherein it is movable about a pivot shaft 18. This motor 19 drives a roller 20 which preferably has a rubber surface. Roller 20 is urged by a spring member 21 against the upper frame portion 4. Inasmuch as spring member 21 is in tension between motor 19 and carrier frame 9, the roller which is driven by motor 19 is retained by the force exerted by spring 21 against upper frame portion 4. Therefore, when the motor is driven, it is moved lengthwise along the upper frame portion 4 and consequently carries with it the entire carrier frame 9.
A sensor 22, which for example comprises a laser, is connected to supporting element 13 which, taken in a direction from the milking parlor, is the rearmost supporting element. With the aid of this sensor 22 it is possible to move the milking robot from a rest position in the longitudinal direction of the milking parlor to a starting position, in which the arms of the milking robot are moved under the animal present in the milking parlor. It is also possible to follow the motions of the animals in the longitudinal direction of the milking parlor. For that purpose, sensor 22 cooperates with a supporting element 23 which is movable against the rear side of the animal. With the aid of a rod system, which in the present embodiment consists of a quadrangular structure, and more particularly a parallelogram structure 24, supporting element 23 is pivotal relative to the milking parlor floor. A plate 26 is mounted on two rods 25 of supporting element 23. Plate 26 is positioned laterally outside frame portions 4 and 5 and is constructed and arranged so that it can reflect a signal transmitted by sensor 22. After sensor 22 has detected the reflected signal, it produces a control signal which is a measure of the actual (i.e. the measured), distance between plate 26 and sensor 22. The control signal causes motor 19 to be driven, whereby milking robot 8 is moved in the longitudinal direction of the milking parlor so that the distance between plate 26 and sensor 22 is brought to and maintained at, respectively, a preset value. Milking robot 8, in its rest or inactive position, is disposed as far as possible to the rear relative to frame portions 4 and 5. In this position, milking robot 8 engages, via a contact element 27, plate 26 and thus maintains supporting element 23 in its rearmost position. In other words, supporting element 23 is held rearwardly by milking robot 8 when the robot is in the rest position. When the milking robot is moved from its rest position in the longitudinal direction of the milking parlor to its starting position, whereby the arms of the milking robot are moved under the animal in the milking parlor, then supporting element 23 is released and urged by the resilient action of a spring 28 located between parallelogram structure 24 and post 7 against the rear side of the cow then in the milking parlor. As the cow moves forwardly or rearwardly, supporting element 23 continues to be urged against the rear side of the animal by the pressure exerted by compression spring 28. Thus, the position of plate 26 is determined by the position of the animal in the milking parlor in the longitudinal direction. Sensor 22, while maintaining a constant distance in longitudinal direction between plate 26 and sensor 22, causes the milking robot to conform to the cow's movements in the longitudinal direction within the milking parlor.
In the present embodiment, pillar 11 of carrier frame 9 extends vertically downwardly to slightly below second frame portion 5. At the bottom side of this pillar 11 there is a horizontal, rearwardly extending strip 29, on which is freely rotatable roller element 30. Lower frame portion 5 comprises a rail and more specifically a rail in the form of a U-shaped beam. Freely rotatable roller element 30 is arranged so it is movable between the two upright edges of the U-shaped beam. Thus, milking robot 8 bears against lower frame portion 5 and, in this position, moves smoothly along second frame portion 5, when milking robot 8 is moved by the motor along first frame portion 4. In addition to carrier frame 9, the milking robot includes a robot arm construction 31 which is predominantly movable in the vertical direction relative to carrier frame 9 with the aid of an operating cylinder 32. Robot arm construction 31 is movably connected to carrier frame 9 by means of a quadrangular structure 33. In the embodiment shown, an upper arm 34 of quadrangular structure 33 is of a fixed length, whereas the lower arm 35 has an adjustable length. This allows the orientation of the robot arm construction 31 to be adjusted to a limited extent. Robot arm construction 31 comprises a predominantly vertical robot arm 36, as well as robot arms 37 which are movable in a predominantly horizontal plane. Vertical robot arm 36 is connected to pillar 11 of carrier frame 9 via quadrangular construction 33. Operating cylinder 32 is operative between carrier frame 9 and robot arm 36. Since the orientation of robot arm 36 is slightly-adjustable with the aid of lower arm 35 of the quadrangular construction 33, the position of the point of contact of operating cylinder 32 with robot arm 36 is not fully defined spatially. For this reason, the housing of operating cylinder 32 is capable of at least a limited degree of pivoting, on a carrier plate 38 connected to beam 10 of carrier frame 9. Mounted on this carrier plate 38 are supports 39, between which the housing of the operating cylinder 32 can move about a pivot shaft 40.
In the present embodiment, operating cylinder 32 is designed as a servo-pneumatic positioning cylinder. This means that at the lower end of its piston rod 41 a position feedback rod 43 is fitted with a plate 42 connected rigidly thereto. A signal is derived in the portion 57 of the operating cylinder by a potentiometer which indicates the position of piston rod 41 relative to the cylinder housing. With the aid of this signal supplied by the potentiometer, the position of piston rod 41 relative to the cylinder housing can be adjusted to a preset position. Operating cylinder 32 is further provided with an overload protection, whereby, as soon as the animal present in the milking parlor exercises pressure on robot arm construction 31, for example by kicking it with its leg, robot arm construction 31 can be moved to its lowest position. In FIGS. 1 and 2, the milking robot 8 is shown in its rest position, wherein it has been moved as far as possible to the rear relative to frame portions 4 and 5 and wherein robot arm construction 31 has been brought to the lowest possible position near the bottom of parlor 1.
When the cow is present in parlor 1 and the milking process is started, milking robot 8 is moved from its rest position to its start position, i.e. it is adjusted to a position in which the arms of milking robot 8 can be moved under the cow.
In the present embodiment, the milking parlor is provided with arms 44, 45 and 46. Arms 44 and 45 are arranged at a fixed angle of 90° relative to each other. Arms 44 and 45 are therefore moved simultaneously by an operating cylinder 47 which is provided between a supporting plate 48 secured to robot arm 36 and a connecting member 49 arranged between arms 44 and 45. Arms 44 and 45 move in an arc about a predominantly vertical pivot shaft 50 between plate 48 and a further supporting plate 48A, the latter plate also being rigidly connected to robot arm 36, more particularly at its bottom side. With respect to arm 45, arm 46 is movable in an arc about a predominantly vertical pivot shaft 51 by means of an operating cylinder 52, which is arranged between arm 46 and that end of arm 45 located near connecting member 49. Teat cups 53 and 54, which are connectable to the teats of the cow, are provided near the end of arm 46. Arranged between the two teat cups 54 is a slide which is movable along arm 46 and on which there is provided a sensor 55 which by a sector-sequential scanning motion can accurately determine the position of the teats. Operating cylinders 32, 47 and 52 are computer-controlled whereby the teat cups can be properly connected to the cows' teats. When robot arms 44, 45 and 46 have been moved to under the cow in parlor 1, the arms are in a relatively low position, in which the sensor 55 has not yet detected the animal's teats. Using the operating cylinder 32, robot arms 44, 45 and 46 are lifted together step-by-step until sensor 55 detects one or more teats of the animal. Should robot arms 44, 45 and 46 be lifted to such an extent that upper edge of the sensor 55 contacts the cow's abdomen, then a switch 56 on the upper side of sensor 55, causes the robot arms to be lowered. Thereafter, the positional determination of the teats with the aid of the sensor 55 can is repeated by a gradual lifting of the robot arms.
The implement, as described above includes a cleaning device 57 for teat cups 53 and 54. This cleaning device 57 is rigidly connected to downwardly directed pillar 11. Cleaning device 57 incorporates four downwardly directed spray nozzles 58. Each spray nozzle 58 has two separate rinsing liquid ducts 59 and 60. Duct 59 extends centrally through the spray nozzle from top to bottom, and laterally directed first flow-out apertures 61 are provided near the lower end of duct 59. When a teat cup is connected to a corresponding spray nozzle, first flow-out apertures 61 have their discharge ends disposed relatively closely under the upper side of the teat cup. The second duct 60 extends approximately concentrically with respect to first duct 59 in the spray nozzle. At the bottom of second duct 60 is an annular second flow-out aperture 62 which is disposed in a plane perpendicular to the longitudinal axis of the spray nozzle and the test cup connected thereto. First duct 59 of each spray nozzle 58 is connected to a rinsing liquid supply line 63. The second duct 60 of each spray nozzles 59 is connected to a pipe section 64. The pipe sections 64 of individual spray nozzles 59 conjoin a distributor element 65 which is connected to a rinsing liquid supply line 66. Rinsing liquid supply lines 63 are connected via pump to a rinsing liquid reservoir (not shown in the drawings). When the milking robot is not operative for milking, as illustrated in FIG. 1, teat cups 53 and 54 are directly under spray nozzles 58, so that, simply and solely by an upward motion of the robot arm carrying the teat cups, the teat cups engage their corresponding spray nozzles 58. FIG. 2 illustrates the situation in which the robot arms have not yet been moved inboard sufficiently so that the teat cups are positioned directly under the spray nozzles of the cleaning device. When, between milking different animals or after milking of the animals, the teat cups and the milking lines connected thereto must be cleaned, then robot arm 46 together with the teat cups are moved under the spray nozzles and then moved upwardly until the spray nozzles engage the openings of the teat cups. In this position, the first flow-out apertures 61 are disposed almost directly below the upper edge of a teat cup and the second flow-out aperture 62 is almost directly above the upper edge of a teat cup. By thereafter supplying rinsing liquids via lines 63 and 64, one rinsing liquid is discharged over the upper surfaces of the teat cup, while the other rinsing liquid is introduced into the teat cups.
During rinsing, by using a three-way valve which while milking connects the milking lines from the teat cups to a centrally located milk tank, the liquid flow path between the teat cups and the milk tank is interrupted and a fluid passageway for the rinsing liquid is provided to, for example, a rinsing liquid reservoir. Thus, the rinsing liquid can be circulated by means of a pump via supply lines 63, liquid ducts 59 and first flow-out apertures 61 into the teat cups and thereafter conveyed to the reservoir through the milking lines connected to the teat cups. The rinsing liquid that is received by the upper sides of the teat cups via lines 64, duct 60, and second flow-out aperture 62 falls on the floor of parlor 1 and is drained therefrom through a gutter. It is considered important that rinsing liquid supply line 64 not be connected to the rinsing liquid reservoir through which liquid is circulated to the teat cups and relevant milking lines. For cleaning, line 64 can be alternatively connected directly to a water tap or indirectly thereto with an intervening element which adds a special cleaning agent or disinfectant. After rinsing, the rinsing liquid must be flushed from all relevant milk lines.
When the teat cups are connected to the spray nozzles, a vacuum is produced in the teat cups. This causes the teat cups to be drawn slightly upwardly over the lower end of the relevant spray nozzles and the second flow-out apertures 62 in spray nozzles 58 are closed. The spacing between the first flow-out apertures 61 and the second flow-out aperture 62 is therefore relatively small, being, for example, in the range of from five to ten millimeters. In a specific embodiment a spacing of seven millimeters has been selected. When the rinsing liquid is supplied at an increased pressure via pipe section 64 through duct 60, liquid from second flow-out aperture 62 is forced out between the lower edge of second flow-out aperture 62 and the slightly resilient upper side of the relevant teat cup to be sprayed in lateral directions. In that situation, it is advantageous to provide around the cleaning device, or around the individual spray nozzles, a screen 67 which drapes over the upper end of the teat cup when received therein.
FIG. 5 illustrates a second embodiment of a cleaning device. This alternative cleaning device 68 includes a carrier plane 69 (See also FIGS. 10, 13 and 15). having thereon four downwardly directed spray nozzles 58. As indicated in FIGS. 4 and 7, each spray nozzle 58 includes two separate rinsing liquid ducts 59 and 60. As described in the preceding embodiment, the rinsing liquid ducts 59 and 60 end in, respectively, lower discharge outlets, referred to herein as the first-flow apertures 61 and an upper discharge outlet referred to herein as the second flow-out aperture 62. In carrier plane 69, spray nozzles 58 are clamped between an upper part comprising a first portion 70 and a lower part comprising a second portion 71. As indicated in FIG. 6, in the surface of first portion 70 there is arranged a first duct system 72. Preferably, first portion 70 is an aluminum plate, in which the pattern of the first duct system has been arranged. The four ducts or channels 73, 74, 75 and 76 of the first duct system 72 connect at their outer ends to the four rinsing liquid ducts 59 of spray nozzles 58. In the second portion 71, a second duct system comprising channel or bores 79 is arranged (FIG. 8). Further, in the second portion 71 of carrier plane 69 there are arranged four downwardly extending openings comprising apertures 78, through which the spray nozzles 58 are received.
In second portion 71, the four bores 79 are arranged on the interior side. Bores 79 are arranged so that each of them extends through the center of an aperture 78 (FIG. 8), and together, opposite apertures 78, they join a first vertical bore 80 which connects to a first nipple 81. Bores 79 are closed along edge of second portion 71 by means of sealing caps 82.
Extending through second portion 71 is a second vertical bore 80A which connects to a second nipple 82A. Bore 80A joins duct system 72 via channel 77. First portion 70 and second portion 71 of carrier plane 69 are clamped firmly together by means of bolts 83, whereby the first portion 70 constitutes a sealing plate closing the upper ends of first and second vertical bores 80 and 80A. Second bore 80A thus provides a fluid passage to first duct system 72 arranged in the first portion 70 and the second portion 71 of the carrier plane 69 constitutes with its surface in the clamped condition a sealing plate for the first duct system 72, including channel 77, arranged in the surface of the first portion 70. FIG. 9 is a plan view of the carrier plane 69 and illustrates how the patterns of the duct system 72 and the second duct system comprising channels 79 are arranged in the two portions 70 and 71.
To obtain a proper sealing of the clamped together portions 70 and 71, it is preferred that the second portion 71 be composed of a relatively soft plastic material and the first portion 70 of aluminum.
In a further embodiment according to FIG. 10, cleaning device 57 includes a cleaning member 84 for cleaning the teats of a milked animal. The cleaning member 84 includes two adjacent cleaning elements in the form of profiled rollers 85, which by their axles are supported rotatably by a gear box 86 which, in turn, is mounted on carrier plane 69. Profiled rollers 85 are driven by an electric motor 87 attached to gear box 86. Cleaning member 84 is bolted together with gear box 86 onto the carrier plane 69 by means of the two bolts 83 which are received through adjacent bores 80 and 80A. Spacer rings 88 are placed between gear box 86 and carrier plane 69 which surround the aforesaid two bolts 83.
If it is desirable to clean the teats of the animal to be milked or an animal that has been milked, carrier plane 69 is carried via spray nozzles 58 received in teat cups 53 and 54 by arm 46 of milking robot 8 to the vicinity of the animal's teats (FIG. 11). Here, using sensor 55, the position of the teats of the milking animal is determined so that rollers 85 are moved to contact both sides of one or more of the animal's teats. After such positioning of rollers 85, the teats are engaged between the oppositely rotating profiled rollers, so that they are in contact with the teats, while between rollers 85, sufficiently to ensure that dirt is removed from them.
After so cleaning the teats and possibly rinsing the teat cups, carrier plane 69 is disengaged from robot arm 46 by being removed from the teat cups. Then, the carrier plane 69 is removed and stored in a further carrier (not shown).
The apparatus described above may also be provided with cleaning system 89 for cleaning the cleaning member 84. The cleaning system 89 comprises a box-like housing 90 attached to the beam 11 of carrier frame 9 by means of an L-shaped box-profile bar or strip 93 (FIGS. 11, 13, 14 and 15). Box-like housing 90 has a slot 91 which is covered by a row of brush hairs 92. The width of slot 91 is greater than the diameter of profiled rollers 85. Thus, it is possible to place profiled rollers 85 in box-like housing 90 by movement of robot arm construction 31. To place rollers 85 in box-like housing 90, they must be moved by means of robot arm 46 to a position that is at the level of and in front of slot 91. By moving robot arm 46 in a horizontal plane towards slot 91, the rollers are inserted into box-like housing 90. Gear box 86 and carrier plane 69, however, are retained outside box-like housing 90. FIGS. 12, 13, 14 and 15, illustrate how rollers 85 are moved into the box-like housing 90. Robot arm 46 raises the teat cups along with carrier plane 69, gear box 86, and rollers, 85, to where the ends of rollers 85 are opposite slot 91, and moves then horizontally whereby rollers 85 are received in housing 90 and carrier plane 69 is below it. After rollers 85 have been so positioned in the box-like housing 90, the vacuum in teat cups 53 and 54 is removed, robot arm 46 is disconnected from spray nozzles 58 of carrier plane 69 and is moved therefrom.
Carrier plane 69 is received by a retention and positioning device 94 by means of which carrier plane 69 is secured relative to box-like housing 90. Retention and positioning device 94 includes two rods 95 which are generally U-shaped in cross-section and have generally the same profile as a hockey stick so that they are similar in form to the edges of carrier plane 69. Rods 95 are disposed on either side of carrier plane 69. The first (on the right as seen in FIG. 15) rod 95 is located under the edge and projecting outwardly and forward of box-like housing 90, and is fixedly connected by means of a support 96A to the L-shaped tube 93 which has a rectangular cross-section and is arranged along the side of box-like housing 90. The second bar 95, (on the left as seen in FIG. 15) is below and projecting forwardly of box-like housing 90. This bar 95 is pivotable about a vertical shaft 96 connected to the under side of housing 90. A lever 97 is pivotally connected on its inboard end to vertical shaft 96 and on its outboard end to cylinder 98. Cylinder 98 is pivotally connected at its other end to a vertical shaft 99 which is retained between two horizontal, interspaced bars 100. Bars 100 are affixed to a tube 101 which has a rectangular cross-section and is attached to tube 93.
FIGS. 13, 14 and 15 indicate how the carrier plane 69 is held in the box-like housing 90 by means of a retention and positioning device designated generally by reference numeral 94. The carrier plane 69 is held by its edges between rods 95, after energizing cylinder 98. As such, carrier plane 69 is always situated in the same position relative to the box-like housing 90. Carrier plane 69 can be released from rods 95 by energizing the cylinder 98, which causes second rod 95, to which is rigidly connected to lever 97, to pivot in the direction of beam 11 (FIG. 15). After second rod 95 is so pivoted, carrier plane 69 is freely movable in a horizontal plane to permit the removal of rollers 25 from slot 91, by means of robot arm 46 to clean the animals' teats. Preferably, the cylinder 98 is pneumatic.
After the animal's teats have been cleaned by means of profiled rollers 85, the rollers are returned to and stored in box-like housing 90 by the robot arm 46. FIG. 14 shows in cross-section how profiled rollers 85 are located in box-like housing 90. For cleaning profiled rollers 85 there are arranged at the upper sides of box-like housing 90 two spray elements 102. Spray elements 102 include a perforated tube, one end of which is closed and the other is connected to a liquid spray line. A cleaning liquid is supplied to the spray elements 102 through the liquid supply line during the cleaning of profiled rollers 85. The perforations in spray elements 102 are arranged so that the cleaning liquid sprays tangentially against profiled rollers 85. At the upper side of box-like housing 90, above each of profiled rollers 85, a row of depending brush hairs 103 are provided which extend to contact profiled rollers 85. During the cleaning of profiled rollers 85, a cleaning liquid is discharged through spray elements 102 to impinge against rollers 85 that are thus caused to rotate against brush hairs 103. In the lower side of box-like housing 90 is a drain opening 104, to which a discharge line is connected. During cleaning, the cleaning liquid originating from spray elements 102 is drained from housing 90 via this discharge line. Preferably, the bottom of the box-like housing 90 is inclined at an angle so the cleaning 12quid flows in the direction of discharge opening 104.
In a further embodiment, according to the invention, the robot arm 46 includes an after-treatment device 105 (FIG. 16) for disinfecting the udder and/or the teats after the animal has been milked. The after-treatment device 105 includes a pressure vessel 106 having stored therein the cleaning and/or disinfecting liquid, and a line 107 leads therefrom which supplies the liquid to a spray nozzle 108 (FIG. 16). A further line 109 is connected to a pressure source through 109 whereby an overpressure is established in pressure vessel 106 of preferably three atmospheres. In supply line 107 to spray nozzle 108 a valve 110 is incorporated by means of which the liquid flow to spray nozzle 108 is selectively closed and opened. Valve 110 may be electromagnetically activated. In a preferred embodiment according to the invention, the valve is arranged near spray nozzle 108, so that the length of the line between the valve 110 and the spray nozzle 108 is relatively short. Therefore, after the valve 110 has been opened, the pressurized liquid in line 107 need only travel a relatively short distance to spray nozzle 108. The advantage of this relatively short travel distance is that, after the valve has been opened, the liquid is sprayed by spray nozzle 108 forms a fan-shape almost immediately. As a result, on opening and closing of valve 110, the occurrences of initial and final discharge phenomena in the production of the fan-shaped spray pattern by the spray nozzle 108 are prevented.
FIG. 17 shows spray nozzle 108 located at the end of robot arm 45 between two front teat cups 53. FIG. 17 indicates how spray nozzle 108 may be advantageously arranged at the end of robot arm 46 of milking robot 8. Spray nozzle 108 is located below the carrier plane 111, on which teat cups 53 rest, and is positioned in a holder 112 connected to a plate 113, which is perpendicular to carrier plane 111. Spray nozzle 108 is positioned in holder 112 so that the fan-shaped spray pattern is directed forwardly and upwardly relative to the end of robot arm 46. In this connection, the fan-shaped spray pattern encompasses, relative to plate 113, an angle of approximately 20°. In carrier plate 111 an aperture is arranged through which the spray liquid of the spray nozzle is sprayed.
The operation of the after-treating device 105 is described hereafter.
After the milking procedure has been terminated, the teat cups 53 are removed from the teats of the animal in parlor 1, and are withdrawn to robot arm 46, where they are supported against carrier plate 111. Subsequently, robot arm 46 is positioned so that the fan-shaped spray pattern from the spray nozzle 108 is received precisely at the rear side at the udder of the milked animal. The positioning of robot arm 46 can be effected by means of the sensor 56 and/or by animal-depending co-ordinates previously supplied to a control computer of robot arm 46. After robot arm 46 has been positioned, valve 110 is opened, while simultaneously the robot arm is moved forwardly in a horizontal plane in the direction of the front side of the animal. Thus, the entire udder is sprayed by the fan-shaped pattern. Because the fan-shaped spray pattern is directed forwardly and upwardly relative to the end of robot arm 46, and because the spraying of the udder is effected from the rear in the direction of the front of the udder, spray liquid originating from the udder and/or the fan shaped spray pattern is prevented from falling into the teat cups. The path to be covered by robot arm 46 in the horizontal plane, and the height of spray nozzle 108 relative to the animal's udder are controlled based on a previous encounter with the animal by a computer controlling the robot arm 46. It is also possible for the appropriate height and the distance to the udder to be determined by sensor 56.
It will be understood that the above-described embodiments of the cleaning device and the after-treating device can be used in an apparatus for automatically milking animals not only in combination, but also separately.
Although we have described the preferred embodiments of our invention, it is to be understood they are capable of other adaptions and modifications within the scope of the following claims. | An apparatus and method for automatically cleaning the teat cups of a milking apparatus. The teat cups are automatically removed by a robot arm from the animal's teats. Nozzles are provided which are automatically inserted into the openings for the teats located on top of the teat cups. In the cleaning operation, the nozzles are, in effect, connected to the teat cups and spray a cleansing and/or rinsing liquid through an upper set of outlets from the nozzle to clean the upper surfaces of the teat cups and through a lower set of nozzle outlets to clean and rinse the interior of the teat cups as well as the lines connected therewith. Associated with the nozzles are rotatable cleaning members for cleaning the animals' teats and udders in the vicinity thereof. Brushes and spray nozzles are provided for automatically cleaning these cleaning members after use. All operations are programmed to occur automatically without human assistance or intervention. | 0 |
This application is a divisional of application Ser. No. 09/103,727 filed Jun. 23, 1998, now U.S. Pat. No. 6,205,110.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a disk drive motor for driving recording disks and, more particularly, to a disk drive motor which is required to operate at high speed with high stability.
2. Description of the Related Art
Various types of recording disks have been proposed and used for the purpose of recording and reproduction of data, such as compact disks (CD), floppy disks (FD), magneto-optical disks (MO), mini-disks (MD), digital video disks (DVD), hard disks (HD), and so forth. Different types of recording disks employ different recording/reproduction methods and have different specifications in regard to the size or capacity of stored data, disk driving speed, recording density, and so on, as well as disk materials and prices. Consequently, drive motors of different specifications are used for driving different types of recording disks.
Nowadays, there is a trend towards a higher degree of sophistication and a greater size of electronic data, as image data are handled more than text data. This has given rise to the demand for inexpensive recording disks and disk drives which are capable of performing quick storage and reproduction of large volumes of information.
For instance, CDs were initially used as music recording/playback media but are nowadays applied for spreading use as CD-ROMs which are major storage disks for computers, by virtue of their advantages over other types of media. This type of storage media offers greater storage capacity and shorter operation time, i.e., reduced seek time, permitting much higher speed of rotation by means of high-speed disk drive motors, thus affording disk rotation speeds 20 times as high as that of music CDs.
FIG. 1 shows the construction of a conventional disk drive motor.
The conventional disk drive motor shown in FIG. 1 has a substantially cylindrical sleeve 3 which at its lower end fits in an opening 2 formed on a base member 1 as a part of a chassis of a disk drive device. The lower opening of the sleeve 3 is closed by a tabular member 4 which carries a thrust bearing member 5 . A sleeve bearing 6 made of an oil-impregnated metal or a wear-resistant resin is received in the sleeve 3 .
A stator 8 includes a stator core 8 a which is secured to the outer surface of the sleeve 3 and stator coils 8 b wound therearound. A shaft 9 is rotatably supported by the sleeve bearing 6 such that it is in contact at its lower end, with the thrust bearing member 5 while its upper end projects beyond the upper end of the sleeve 3 . A rotor hub 10 made of non-magnetic material such as aluminum is fixed to the upper end of the shaft 9 . A yoke 11 made of magnetic material such as iron is fixed to the rotor hub 10 .
The yoke 11 has a disk-shaped base portion and a cylindrical skirt portion which is integrally formed with the base portion and extends downward from the radially outer end of the base portion. The sleeve 3 is received in a central opening formed at the center of the base portion of the yoke 11 . The inner peripheral edge of the base portion defining the central opening is fixed to a lower end portion of the rotor hub 10 . An annular rotor magnet 12 is fixed to the inner peripheral surface of the cylindrical skirt portion of the yoke 11 , so as to radially face the stator 8 .
A turntable 14 which is secured to the outer peripheral surface of the rotor hub 10 carries a recording disk D, through an intermediary buffer member 15 . A clamp magnet 16 is provided in a recess formed on the top of the rotor hub 10 , such that the upper surface of the clamp magnet 16 is flush with the top surface of the rotor hub 10 . The clamp magnet 16 magnetically attracts a disk pressing means (not shown) on the disk drive unit, thereby fixing the recording disk D.
In operation, electrical current supplied to the coils 8 b of the stator 8 serves to generate magnetic force which acts between the stator 8 and the rotor magnet 12 so as to induce a torque for rotation. As a consequence, the rotor magnet 12 , the yoke 11 , the rotor hub 10 and the shaft 9 rotate as a unit, relative to the stator 8 which is stationary, whereby the turntable 14 and, hence, the recording disk D thereon rotate in a predetermined direction.
When such a conventional motor is driven at high speed, there occurs a problem which is not serious when the conventional motor is driven at low speed. Namely, high speed driving of the motor makes is difficult to control and regulate motor performance such as run-out of the rotary part, vibration and noise of the motor. In particular, when the run-out of the rotary part increases, storage and reproduction of data become less reliable.
Run-out, vibration and noise are considered to be attributable to slight local dimensional errors which produce only negligibly small effect in low speed driving but shows serious effect on high speed driving as described above, resulting in imbalance of motor parts under rotation.
It is true that rotational performance of the conventional motor structure shown in FIG. 1 can be improved to some extent when, for example, the shaft 9 and the sleeve bearing 6 are machined, finished and mounted with higher degree of precision. This solution, however, is still unsatisfactory from the viewpoint of production costs.
Rotational performance is also affected by any dimensional error of the recording disk, particularly when the rotation speed is high. When production costs of disks are considered, however, it is difficult and impractical to achieve a higher dimensional precision of recording disks.
It is materially impossible to completely eliminate any dimensional error and mass imbalance of the rotary system including the motor and the disk. Under this circumstance, a demand exists for a measure which improves the rotational performance while allowing dimensional error and mass imbalance to some extent.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a disk drive motor of which impairment of rotational performance, in particular run-out of the rotary part of the motor, is suppressed at high speed operation of the motor.
Another object of the present invention is to provide a disk drive motor that offers high rotational performance while accommodating dimensional errors of the motor and disk.
It is still another object of the present invention to provide a disk drive motor which can be fabricated at reduced costs but yet is capable of operating with high rotational performance.
To attain those objects, a disk drive motor according to the present invention comprises a rotor having an annular space formed therein coaxially with the axis of rotation, and balancing members accommodated in the annular space and capable of changing its mass distribution circumferentially along the circle of the annular space.
When the motor speed is low, the balancing members assume random positions within the annular space. As the motor is driven at speed beyond a predetermined value, the balancing members distribute at equal spaces along the radially outer circumferential surface of the annular space, due to effect of centrifugal force. In case of any imbalance occurring during the rotation, the balancing members temporarily gather to a portion of the annular space where the mass imbalance is taking place. However, when the motor speed exceeds the value at which resonance takes place due to coincidence between the frequency of the vibration of the balancing members and the natural frequency of the motor, the balancing members move to a position symmetrical with the point of mass imbalance to eliminate the mass imbalance, thereby suppressing the run-out.
The drive motor may have means for urging the balancing members radially inward so as to prevent the random movement of the balancing members during low-speed operation of the motor. Such urging means effectively urges the balancing members towards the radially inner end of the annular space, thereby reducing vibration and noise which otherwise may be produced due to random movement of the balancing members within the annular space during low-speed operation of the motor.
The radially inward urging means may be constituted by a tapered bottom surface of the annular space inclined radially inward and downward, or by magnets arranged at the radially inner or outer end of the annular space so as to urge the balancing members made of a magnetic member radially inward by magnetic attracting or repellent force.
When such a magnetic urging means is used for urging the balancing members radially inward, the magnets may be held by yokes which form a gap along the surface of the magnets acting on the balancing members. The size of the gap is determined in accordance with the motor speed and the level of the centrifugal force, so as to optimize the force acting on the balancing members.
The above and other objects, features and advantages of the present invention will become clear from the following description of the preferred embodiments when the same is read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a conventional disk drive motor.
FIG. 2 is a cross-sectional view of a first embodiment of the disk drive motor in accordance with the present invention.
FIG. 3 is a cross-sectional view of a second embodiment of the disk drive motor in accordance with the present invention.
FIG. 4 is a cross-sectional view of a third embodiment of the disk drive motor in accordance with the present invention.
FIG. 5 is a perspective view of a coiled spring used in a fourth embodiment of the disk drive motor in accordance with the present invention.
FIG. 6 a is a plan view of a leaf spring used in a fifth embodiment of the disk drive motor in accordance with the present invention.
FIG. 6 b is a perspective view of the leaf spring shown in FIG. 6 A.
FIG. 7 is a cross-sectional view of a sixth embodiment of the disk drive motor in accordance with the present invention.
FIG. 8 a is a cross-sectional view of a seventh embodiment of the disk drive motor in accordance with the present invention;
FIG. 8 b is a fragmentary sectional view of a motor incorporating the embodiment shown in FIG. 8 a;
FIG. 9 is a fragmentary sectional view of an eighth embodiment of the disk drive motor in accordance with the present invention.
FIG. 10 is a fragmentary sectional view of a ninth embodiment of the disk drive motor in accordance with the present invention.
FIG. 11 is a fragmentary sectional view of a tenth embodiment of the disk drive motor in accordance with the present invention.
FIG. 12 is an enlarged view of a critical portion of an eleventh embodiment of the disk drive motor in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the present invention will be described with specific reference to FIG. 2 .
With reference to FIG. 2, a disk drive motor of the first embodiment has a stationary member 21 as a part of a chassis of disk driving device and a stationary cylindrical sleeve member 22 which is secured at its lower end to the brim of an opening 23 formed in the stationary member 21 . A circular plate member 24 is fixedly secured to the bottom opening of the sleeve member 22 to close the opening. A thrust bearing member 25 is fixed to the upper surface of the circular plate member 24 so as to be positioned at the bottom of the sleeve member 22 . And a sleeve bearing 26 which made of an oil-impregnated metal or a wear-resistant resin, is secured to the inner peripheral surface of the sleeve member 22 .
The disk drive motor further has a stator 28 which includes a stator core 28 a fixed to the outer surface of the sleeve member 22 and coils 28 b wound around the stator core 28 a , and a shaft 29 . The lower end of the shaft 29 is held in contact with the thrust bearing member 25 and the upper end of the shaft 29 projects beyond the upper end of the sleeve member 22 . The shaft 29 serves as a part of rotor and is rotatably supported by the sleeve bearing 26 . A turntable 30 made of a non-magnetic material such as aluminum is attached to the upper end of the shaft 29 and also serves as a part of the rotor.
A yoke 31 is made of magnetic material such as iron and has a disk-shaped base portion and a cylindrical skirt portion integrally formed with the base portion and extending downward from the radially outer end thereof. The sleeve 22 is positioned within an opening formed at the central portion of the base portion of the yoke 31 . The inner peripheral edge of the base portion defining the opening is secured to a lower end portion of the turntable 30 . A rotor magnet 32 is fixedly secured to the inner peripheral surface of the cylindrical skirt portion of the yoke 31 so as to oppose the stator 28 . A recording disk D such as a CD-ROM is mounted on the upper surface of the turntable 30 through an intermediary buffer member 33 .
The turntable 30 is formed with an annular recess 35 on its bottom. The lower opening of the annular recess 35 is closed by the upper surface of the base portion of the yoke 31 , whereby a closed annular space 36 is formed. The annular space 36 accommodates a plurality of balls 37 made of steel. The annular space 36 and the balls 37 accommodated therein constitutes a balancer 38 which serves to correct any mass imbalance of the rotor. The annular space 36 is formed coaxially with the shaft 29 . The radial width of the annular space 36 is determined to be slightly greater than the diameter of the balls 37 , so that the balls 37 are allowed to move in the circumferential direction along the walls of the annular space 36 .
The embodiment shown in FIG. 2 employs nine (9) balls 37 . The sum of the diameters of these nine balls 37 is not greater than about one eighth (⅛) of the outer circumferential length of the annular space 36 . The rest of the annular space 36 , amounting to about seven eighth (⅞) or more of the outer circumference provides the clearance for the movement of the balls 37 .
Referring further to FIG. 2, a clamp magnet 39 is provided within a recess formed on the top of the turntable 30 such that the upper surface of the clamp magnet 39 is substantially flush with the top surface of the turntable 30 . The clamp magnet 39 is adapted to magnetically attract disk pressing means (not shown) provided on the disk driving device, thereby stably fixing the recording disk D.
When current is supplied to the coils 28 b of the stator 28 , a magnetic force which acts between the stator 28 and the rotor magnet 32 is induced. As a result, the rotor magnet 32 , the yoke 31 , the turntable 30 and the shaft 29 rotate relative to the stator 28 which is kept stationary, whereby the disk D is rotated in a predetermined direction.
In the following, explanation will be made about the operation of the balancer 38 when the recording disk D such as a CD-ROM is driven by the motor of this embodiment.
When the rotor of the motor rotates imbalancedly, for example, the rotor rotates in a condition inclined to imbalanced direction. After the motor starts to rotate, the balls 37 move in a random manner within the annular space 36 until the motor speed exceeds a resonance speed at which resonance takes place due to coincidence between the natural frequency of the motor and the natural frequency of each ball 37 . More specifically, in this period, the balls 37 are distributed to random positions around the axially lowermost portion of the annular space 36 by the gravity. Consequently, the rotor rotates in an unstable manner, with the axis of rotation of the rotor being deflecting from the axis of the shaft 29 , as a result of momentary shift of the masses due to the random movement of the ball 37 .
At the rated speed above the resonance speed, a 180 degree (180°) of phase difference appears between the centrifugal force generated by the mass imbalance and the displacement of the balls 37 , and the balls 37 are moved in such directions to cancel the mass imbalance and a counter-centrifugal or automatic centering effect is produced. Thus, the balls 37 are concentrated to a position that is symmetrical with the position of the initial mass imbalance of the motor with respect to the axis of rotation, so as to cancel the mass imbalance. In this state, the rotary part of the motor can stably rotate about an axis that coincides with the axis of the shaft 29 .
On the other hand, when the rotor rotates balancedly, in this case also, the rotation of the rotor is rendered unstable due to momentary shift of the masses caused by random movement of the balls 37 , until the motor speed exceeds the resonance speed at which resonance takes place due to coincidence between the natural frequency of the motor and the natural frequency of the balls 37 . In this case, however, the balls 37 are moved to three positions that are spaced at 120 degree (120°) from one another, such that three balls 37 are concentrated to each of these three positions, at the rated speed above the resonance speed. Thus, the balls 37 behave not to impair the original mass balance by themselves.
As will be understood from the foregoing description of the first embodiment of the present invention, the balls 37 in the annular space 36 move to automatically cancel any mass imbalance of the rotor during operation at the rated speed. Thus, any mass imbalance is automatically corrected, so that the run-out of the rotor can effectively be avoided without requiring extremely high degree of dimensional precision of the motor parts. It is also to be appreciated that the rotor together with the recording disk D can stably rotate despite any dimensional error, regardless of whether such dimensional error exists in the rotor or in the disk D. In addition, when there is no mass imbalance in the rotary system composed of the rotor and the disk D, the balls 37 behave so as not to impair this balance.
Although the balls 37 made of a steel are used in this embodiment, the balls 37 may be made of other materials such as ceramics, rubber, plastics or the like equally as well. The balls 37 inevitably collide with one another and with the walls of the annular space 36 during the random movement. In order to suppress generation of noise attributable to the collision, it is advisable to use the balls 37 made of soft material. For instance, generation of noise can appreciably be suppressed when the balls 37 are made of composite material composed of a steel core ball clad with a resin coating or of a rubber which itself is a soft material.
The balls 37 of any of the above-mentioned material can smoothly move within the annular space 36 so as to quickly correct any mass imbalance. In particular, noises due to collision and friction during random movement of the balls 37 can effectively be suppressed when the surfaces of the balls 37 are coated with soft material such as soft resin. Such coating is also effective in protecting the balls 37 from damages and rusting. The coating further offers advantages such as quietness, cleanness and durability of the motor.
In the described embodiment, the annular space 36 is defined between the lower surface of the turntable 30 and the upper surface of the base portion of the yoke 31 . This arrangement enables the balls 37 as the balancing member to be disposed in a neat and compact manner, without affecting structures of major motor parts such as the rotor magnet 32 and the stator 8 . In addition, this arrangement serves to facilitate the balancing because the position of the annular space 36 , between the lower surface of the turntable 30 and the upper surface of the yoke 31 , is close to the center of gravity of the rotary member including the rotor and the disk D.
The above described first embodiment employs nine (9) balls 37 which are sized such that the sum of the diameters of these nine (9) balls 37 amounts to a value which is not greater than about one eighth (⅛) of the outer circumferential length of the annular space 36 . This also is only illustrative and the number, size and specific gravity of the balls 37 to be accommodated in the annular space 36 may be suitably selected depending on factors such as expected degree of mass imbalance.
It is to be understood, however, a single ball cannot provide the advantage of the invention. In order to deal with a variety of forms of mass imbalance, it is necessary to employ at least two balls. Experiments showed that appreciable effect is obtained when the number of the balls 37 employed is an integer multiple of 3, e.g., 6 or 9. This is attributable to the fact that the balls 37 are equally distributed to three positions spaced at 120 degree (120°) from one another, offering a greater degree of stability as compared with the case where the balls 37 are equally distributed to two or four positions.
It is also necessary that the sum of diameters of the balls 37 accommodated in the annular space 36 does not exceed half the outer circumferential length of the annular space 36 , for otherwise a ball or balls out of the half circumference of the annular space 36 act to impair the rotational mass imbalance.
A second embodiment of the present invention will be described with reference to FIG. 3 . In this Figure, the same reference numerals as those used in FIG. 1 are employed to denote parts or components of the second embodiment which are the same or equivalent to those of the first embodiment. Detail of such same or equivalent parts is not made for the purpose of clarification.
In the second embodiment, the radial width of the annular space, denoted by numeral 42 , is large in comparison with the diameter of the balls 37 . More specifically, the radial width of the annular space 42 is about twice as large the diameter of the balls 37 , so that the balls 37 are movable not only in the circumferential direction but also in the radial direction within the annular space 42 .
In this embodiment, the disk-shaped base portion of the yoke 31 , presenting the bottom surface of the annular space 42 , has a radially outer end portion which is curved upward to ascend towards the radial end extremity and a radially inner end region which is curved downward to descend towards the center. Consequently, the axial height of the annular space 42 varies along the radius so as to progressively decrease towards the radial end extremity. With this arrangement, the balls 37 stagnate in the radially innermost region, i.e., in the axially lowest region of the annular space 42 , when the drive motor is not operating.
Due to a reason pertaining to the operation principle for recording and reading data to and from a CD-ROM, it is a common measure to vary the rotation speed of the disk depending on the radial position of the tracking. Namely, the rotation speed during tracking on a radially outer track is different from that during tracking on a radially inner track. In the second embodiment, correction of imbalance can be performed momentarily in response to the change of the rotation speed within the rated speed range. This owes to the fact that the annular space 42 has the radial width which is sufficiently greater than the diameter of the balls 37 allowing the balls 37 to momentarily change their radial position.
The operation of the motor of the second embodiment shown in FIG. 3 is similar to that of the first embodiment shown in FIG. 2, before the motor speed reaches the resonance speed at which resonance takes place due to coincidence between the natural frequency of the motor inclusive of the recording disk D mounted thereon and the natural frequency of the balls 37 . Namely, the balls 37 move in a random manner along the inner periphery of the annular space 42 , before the above-mentioned resonance speed is reached.
During operation at a speed falling within the rated speed range above the resonance speed, the balls 37 are moved and concentrated to a region which is in symmetry with the imbalance mass with respect to the axis of rotation, whereby the mass imbalance is canceled to allow the rotor to stably rotate about the axis which coincides with the axis of the shaft 29 . A variation of the motor speed within the rated speed range causes a corresponding change in the centrifugal force acting on each ball 37 . In this embodiment, since the annular space 42 is designed to allow the balls 37 to move not only in the circumferential direction but also in the radial direction, the balls move to radial positions corresponding to the rotation speed, so as to maintain stable rotation of the rotor.
Thus, in the second embodiment, the annular space 42 has an ample radial width for the diameter of the balls 37 so as to allow the balls 37 to move not only in the circumferential direction but also in the radial direction. Therefore, even when the rotation speed is changed within the rated speed range, stable rotation is ensured by virtue of the movement of the balls 37 to a radial position corresponding to the rotation speed.
The base portion of the yoke 31 , which closes the lower opening of the annular recess 41 so as to act as the bottom wall of the annular space 42 , is tapered such that the radially outer end portion is curved upward while the radially inner end portion is inclined downward towards the axis of rotation. Consequently, a composite force composed of the force of gravity and a reacting force perpendicular to the plane of the bottom surface of the annular space 42 is generated so as to urge the ball 37 radially inward, i.e., towards the axis of rotation. When the motor is not operating, the balls 37 rest at the radially innermost region of the annular space 42 . However, when the motor is operating, the force acting on each ball 37 is determined by subtracting from the above-mentioned inward urging force and the centrifugal force proportional to the rotation speed. Thus, the balls 37 are held at a radial position where a balance is obtained between the radially inward urging force provided by the tapered bottom surface of the annular space 42 and the radially outward centrifugal force. It is thus possible to control the radial position of the balls 37 based on the relationship between the radially inward urging force and the centrifugal force. This means that the radial positions at which the balls 37 are held can be set as desired, such that, for example, the balls 37 are held at a radially inner position when the rotation speed is below the resonance speed and at a radially outer position when the rotation speed is not lower than the resonance speed, by suitably determining the gradient of the taper of the bottom surface of the annular space 42 as a design parameter, in addition to the factors such as the diameter and number of the balls 37 and the motor speed. Obviously, the balls 37 are held at the radially innermost region of the annular space 42 when the motor is not operating, because no centrifugal force acts on the balls 37 . Therefore, the motor can be started always at the same state of balance.
A description will now be given of a third embodiment of the present invention, with specific reference to FIG. 4 .
In this embodiment, the turntable 30 has a flat lower surface and the yoke 31 is secured to the shaft 29 . A basin-shaped member 44 having a disk-shaped base portion with upwardly curved outer peripheral portion is disposed between the lower surface of the turntable 30 and the upper surface of the base portion of the yoke 31 and is fixed to the shaft 29 . The upper end of the basin-shaped member 44 is held in contact with the lower surface of the turntable 30 , whereby a closed annular space 45 is formed.
Since the annular space 45 is provided by the basin-shaped member 44 held in contact at its upper end with the lower surface of the turntable 30 , the radial span of the annular space 45 is further increased over that in the motor of the second embodiment shown in FIG. 2 . Thus, the balls 37 are allowed to travel a sufficiently large radial distance which is determined by subtracting the radius of the shaft 29 from the radius of the motor.
The greater amount of radial movement of the balls 37 afforded in this embodiment offers a correspondingly greater adaptability to variation of the motor speed. In addition, the drive motor of this embodiment can be fabricated without difficulty, because the annular space 45 is formed by the basin-shaped member 44 , without requiring any specific machining on the lower surface of the turntable 30 .
The annular space 45 having an ample radial span equivalent to that provided by the basin-shaped member 44 in this embodiment can also be formed by a suitable combination of the turntable 30 and the yoke 31 as in the cases of the first and second embodiments. It is also to be understood that the annular space 45 in the third embodiment may have a bottom surface tapered downward towards the axis of rotation, as in the second embodiment shown in FIG. 3 .
A description will now be given of a fourth embodiment and a fifth embodiment of the disk drive motor in accordance with the present invention, with reference to FIGS. 5, 6 a and 6 b.
Referring first to FIG. 5, a disk drive motor as the fourth embodiment of the present invention employs a ring-shaped coiled spring 47 . This coiled spring 47 has a small spring constant, and serves as the balancing member, in place of the discrete balls 37 used as the balancing member in the first to third embodiments. Thus, the ring-shaped coiled spring 47 may be accommodated in the annular space 39 , 42 or 45 of any of the preceding embodiments, so as to extend in the ring-like form along the inner circumferential surface of the annular space 39 , 42 or 45 .
Referring now to FIGS. 6a and 6b, a disk drive motor as the fifth embodiment incorporates a ring-shaped leaf spring 49 which serves as the balancing member in place of the discrete balls 37 of the first to third embodiments and the coiled spring 47 used in the fourth embodiment. The ring-shaped leaf spring 49 also may be accommodated in the annular space 39 , 42 or 45 of any of the preceding embodiments, so as to extend in the ring-like form along the inner circumferential surface of the annular space 39 , 42 or 45 .
In operation, the ring-shaped coiled spring 47 or the ring-shaped leaf spring 49 is deflected in such a manner that a dense portion of the spring is formed locally in the region that is symmetrical with the mass unbalance with respect to the axis of rotation. Therefore, mass is increased locally in that region, thereby canceling any mass unbalance.
The fourth and fifth embodiments as described above are free from the problem of noise such as the chattering noise which is inevitable in the first to third embodiments incorporating freely movable the balls 37 , thus offering disk drive motors which operate with reduced noise. In addition, the disk drive motors of the fourth and fifth embodiments are easy to assemble, by virtue of the reduced number of parts.
The ring-shaped leaf spring 49 used in the fifth embodiment is heavier than the coiled spring 47 used in the fourth embodiment. The fifth embodiment is therefore suitable for use in the case where the balancing member is required to have a large mass.
The balancing member may also be implemented by using, for example, a magnetic fluid, oil, mercury, a gel or particles such as sand. When a magnetic fluid is used as the movable balancing mass, it is advisable to dispose a magnet as a leak prevention means at a suitable position such as a position near the fluid filing opening or near the gap. It is also advisable to apply an oil-repellent material as the leak prevention means, when oil is used as the balancing mass.
A sixth embodiment of the present invention will be described with reference to FIG. 7 .
It will be seen from FIG. 7 that the annular space denoted by numeral 52 has a radial width slightly greater than the diameter of the balls 37 .
In this embodiment, the disk-shaped base portion of the yoke 31 presents the bottom surface of the annular space 52 and has a radially outer end portion which is curved upward to ascend towards the radial end extremity and a radially inner end region which is curved downward to descend towards the center. Consequently, the axial height of the annular space 52 varies along the radius so as to progressively decrease towards the radial end extremity. With this arrangement, the balls 37 stagnate in the radially innermost region, i.e., in the axially lowest region of the annular space 52 , when the drive motor is not operating.
An inner wall 50 a of the annular recess 50 defining the annular space 52 is partly removed to provide a circumferential groove 50 c . An annular magnet 54 is received in the circumferential groove 50 c , so as not to project outward beyond the surface of the inner wall 50 a . Since the outer surface of the annular magnet 54 is recessed from the surface of the inner wall 50 a , the balls 37 are not allowed to directly contact with the annular magnet 54 , even when the balls 37 are moved radially inward into contact with the inner wall 50 a . The annular magnet 54 is therefore protected from damaging force which otherwise may be applied thereto due to direct contact with the balls 37 . The annular magnet 54 may be pre-fabricated and fixed by an adhesive or the like in the circumferential groove 50 c , or may be integrally molded with the inner wall 50 a.
The operation of the disk drive motor shown in FIG. 7 in the case of an imbalance of the rotary mass is as follows. The motor together with the recording disk mounted thereon starts to rotate and accelerates. In the transient period before the aforesaid resonance speed is exceeded, the balls 37 are held in contact with the inner wall 50 a of the annular space 52 by an inward concentric force and are allowed to move only in circumferential directions. In this case, the inward urging force is the sum of the magnetic attracting force exerted by the annular magnet 54 and the radially inward urging force produced as a result of the inward and downward inclination of the base portion of the yoke 31 . In this transient period, therefore, the balls 37 move in a random manner along the inner peripheral region of the annular space 52 . Consequently, the rotor together with the disk D rotates in unstable manner with the axis of rotation of the rotor being deflecting from the axis of the shaft 29 , as in the case of the motor shown in FIG. 2 .
When the motor is operating at a speed falling within the rated speed range above the resonance speed, the centrifugal force acting on the ball 37 overcomes the inward concentric force. Therefore, the balls 37 move radially outward apart from the inner wall 50 a of the annular space 52 so as to be concentrated to a region which is in symmetry with the position of mass imbalance with respect to the axis of rotation. Consequently, the mass imbalance is canceled and the motor can operate stably and smoothly with the axis of rotation maintained in alignment with the axis of the shaft 29 .
If no inward concentric force acts on the balls 37 , the balls 37 will start to move to the radially outermost region of the annular space 52 immediately after the start up of the motor, resulting in a tremendously imbalanced rotation. In this embodiment, however, the balls 37 do not move apart from the inner wall 50 a of the annular space 52 when the rotation speed is still below the rated speed range, because the inward concentric force is imposed on the balls 37 such that the balls 37 start to leave the radially innermost region of the annular space 52 only after the motor reaches a speed near the rated speed range. In addition, since the balls 37 are restrained from moving radially outward within the annular space 52 when the motor is not operating, it is possible to prevent generation of noise which otherwise would occur due to collision of the balls 37 with, for example, the walls of the annular space 52 during movement or portage of the drive unit.
A seventh embodiment of the present invention will be described with reference to FIGS. 8 a and 8 b.
As shown in FIG. 8 a , the radially outer surface of the inner wall 50 a of the annular space 52 is partially removed at its heightwise central portion, so as to provide a circumferential groove 50 d which opens radially outward. An annular magnet 56 is received in this circumferential groove and. A lower wall 50 e is formed on the radially outer surface of the inner wall 50 a so as to extend radially outward therefrom. The lower wall 50 e defines the lower end of the circumferential groove 50 d and is positioned between the lower end portion of the annular magnet 56 and the base portion of the yoke 31 .
The lower wall 50 e offers the following advantage. In the assembly of the disk drive motor of this embodiment, the yoke 31 is fixed by caulking to the inner wall 50 a of the annular space 52 so as to be integral with the turntable 30 , as at 50 f . The stress generated as a result of the caulking is borne by the lower wall 50 e which acts as a buffer member, without directly acting on the annular magnet 56 . It is thus possible to protect the annular magnet 56 from damaging force and, therefore, to reduce the risk of production of inferior products.
FIG. 8 b shows a modification of the disk drive motor of the seventh embodiment. In this modification, thin-walled magnetic rings 58 and 60 are disposed on both axial ends, i.e., upper and lower ends shown in the FIG. 7, of the annular magnet 56 . Thus, the magnetic rings 58 and 60 , with the annular magnet 56 sandwiched therebetween, are disposed on the radially outer side of the inner wall 50 a . The outside diameters of the magnetic rings 58 and 60 are greater than that of the annular magnet 56 , so that these magnetic rings 58 and 60 serve to prevent the balls 37 from directly contacting with the annular magnet 56 . Thus, the magnetic rings 58 and 60 provide a buffering function that protects the annular magnet 56 from damaging force. At the same time, magnetic circuits are formed through the magnetic rings 58 and 60 as indicated by an arrow “A”, with the result that the magnetic fluxes from the annular magnet 56 are concentrated to effectively and appropriately attract the balls 37 .
A explanation will now be given of the eighth embodiment of the present invention, with specific reference to FIG. 9 .
An annular magnet 62 , which is sandwiched between upper and lower magnetic rings 64 and 66 , is disposed on the radially inner side of the inner wall 50 a of the annular space 52 . More specifically, the outer peripheral edges of the magnetic rings 64 and 66 are lightly pressed into a recess formed in the inner peripheral surface of the inner wall 50 a , whereby the annular magnet 62 is secured to the inner wall 50 a.
In this embodiment, therefore, the annular magnet 62 is not positioned within the annular space 52 . Consequently, no direct contact or collision occurs between the balls 37 and the annular magnet 62 , so that the annular magnet 62 is protected against damaging force which otherwise would be caused by direct contact or collision. In addition, the assembly can be facilitated because of the simplified structure of the annular space 52 .
A ninth embodiment of the present invention will be described with reference to FIG. 10
This embodiments employs a magnetic ring 68 made of iron and received in a circumferential groove 50 d formed in the radially outer surface of the radially inner wall defining the annular space 52 . The balls 70 are made of magnets.
Inward concentric force acts on the balls 70 to urge these balls 70 towards the axis of rotation. In this case, the inward concentric force is the sum of the magnetic attracting force acting between the balls 70 and the magnetic ring 68 and the force generated due to downward and inward inclination of the base portion of the yoke 31 . In this embodiment, the magnetic ring 68 can be formed from a comparatively hard material such as iron and, therefore, is less liable to be broken by a stress that is produced when the yoke 31 is caulked to the turntable 30 .
A tenth embodiment will be described with reference to FIG. 11 .
In this embodiment, the inner circumferential surface 72 a of the annular recess 72 defining the annular space 36 has been partly removed to provide a circumferential groove 72 c . An axially magnetized annular magnet 74 is received in the annular groove 72 c . Supporting yokes 76 that are made of a magnetic material such as iron are disposed on both axial ends, i.e., upper and lower ends shown in the FIG. 11, of the annular magnet 74 . Each of the yokes 76 has an annular portion 76 a and an axial portion 76 b formed by bending the radially outer end of the annular portion 76 at a right angle thereto so as to extend along the outer peripheral surface of the annular magnet 74 . Thus, the annular magnet 74 is embraced by the pair of holding yokes 76 .
Referring to FIG. 11, numeral 78 denotes a gap formed between opposing axial portions 76 b of the supporting yokes 76 . The gap extends circumferentially along the outer peripheral surface of the annular magnet 74 . Numeral 80 denotes a cylindrical spacer which is made of non-magnetic material, typically rubber or plastics, and which is disposed on the radially outer side of the axial portions 76 b of both holding yokes 76 .
Magnetic fields from the annular magnet 74 for attracting the balls 37 are formed through the holding yokes 76 . The density of the magnetic fluxes is controllable by varying the size of the gap 78 in the direction of magnetization of the annular magnet 74 . The level of the magnetic attracting force has been determined such that a balance is obtained between the magnetic attracting force and the centrifugal force acting on the balls 37 when the motor is operating at a predetermined speed of rotation which is slightly higher than the critical speed of the drive unit incorporating the motor but is below the rated speed.
Thus, in the tenth embodiment of the preset invention, the magnetic attracting force exerted on the balls 37 by the annular magnet 74 can be controlled by suitably selecting the size of the gap 78 between the opposing axial portions 76 b of both holding yokes 76 . The tenth embodiment, therefore, permits a common use of the same annular magnet 74 in a variety of motors to be incorporated in disk drive units having different critical speeds, thus offering a great advantage from the view point of production costs.
FIG. 12 shows a modification in which only one of the pair of holding yokes 76 is provided with the axial portion 76 b . In this modification, the axial length of the sole axial portion 76 b is suitably selected to optimize the size of the gap denoted by 82 .
While the invention has been described in detail herein in accordance with certain preferred embodiments thereof, many modifications and changes therein may be effected by those skilled in the art. Accordingly, it is intended by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | The present invention discloses a disk drive motor comprising a rotor having an annular space formed therein coaxially with the axis of rotation, and balancing member accommodated in the annular space and capable of changing its mass distribution circumferentially along the circle of the annular space. In case of any imbalanced rotation occurring during the rotation, the balancing member temporarily gather to a portion of the annular space where the mass imbalance is taking place. However, when the motor speed exceeds the value at which resonance takes place due to coincidence between the frequency of the vibration of the balancing member and the natural frequency of the motor, the balancing members move to a position symmetrical with the point of mass imbalance to eliminate the mass imbalance, thereby suppressing the run-out. | 5 |
BACKGROUND OF THE INVENTION
The present invention pertains to a cutting apparatus for sewing machines which serves to sever chains of stitches that interconnect successively sewn workpieces as they leave the sewing zone as well as the cutting of tapes or other attachments applied to the workpieces or when desired, the actual cutting of the workpieces.
More particularly, the invention relates to a cutting apparatus for sewing machines having a work surface over which the workpieces are caused to advance during seaming and which is provided with a fixed counter-blade mounted in said work surface downstream of the machine's stitching instrumentalities. The apparatus also includes a movable blade pivotably mounted above the work surface and a means for actuating said movable blade so that it is pivoted downwardly a distance to intersect the path of travel of the workpieces and to a position of operative engagement with the fixed counter-blade. Additionally, this movable blade is usually provided with some form of protective guard surrounding the area of its travel.
With the known cutting apparatuses of this type, it is obvious that the protective guards serve to prevent injury to the fingers of an operator while the movable blade is performing its intended function. It is also obvious that these protective guards should be arranged so as to provide a shield in all possible areas that an operator could accidentially come into contact with the movable blade.
The known forms of protective guards have what is considered certain disadvantages during seaming, cutting or the separation of one workpiece from another due to the reduced amount of free space between the lower edge of the guard and the worksurface of the machine so that frequently there is an interference with the proper advance of a workpiece. As is well known, workpieces are often partially complete with the addition of attachments sewn thereon, and for this reason cannot always be advanced in a sufficiently flattened state to prevent an interference with the known types of protective guards.
Although regulations require that such guards be used with this type of cutting apparatus, it is common knowledge that operators frequently remove them for obvious reasons of preventing such interferences and to increase the number of pieces they can produce in a given period of time.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a cutting apparatus for sewing machines of the type described above, in which positive protection of the operator is provided without possible interference with the workpieces as they are advanced to the area of the movable knife and its protective guard. This object is accomplished by providing a cutting apparatus having a protective guard mounted in a manner whereby in timed sequence with movement of the movable blade, it is caused to move in a direction parallel with said movable blade. The guard is movable by any suitable actuating means from a first position where its lower edge is disposed in spaced relation above the machine's working surface to a second position where its lower edge is located relatively close to said working surface. The movable blade is provided with an actuating means that is operatively associated with the protective guard's actuating means in a manner whereby said blade can only be actuated after said guard has reached a pre-determined position during its movement toward its operating or second position.
In other words, a protective guard is provided which can be actuated either automatically or manually between an elevated position where there is no possible chance of an interference with a workpiece and a lowered position whereat it provides positive protection against injury to an operator. With the actuating means of both the movable blade and the protective guard being operatively associated, a means is provided whereby said movable blade is unable to perform its intended function until it receives a signal indicating that said protective guard has arrived at a pre-determined position whereat the operator will be fully protected from the cutting action of said movable blade.
Upon completion of the cutting operation, both the movable blade and the protective guard are caused to return to their inactive or elevated positions and they need not follow a sequence that is the reverse of that utilized when they were actuated.
These and other objects of the invention will become more fully apparent by reference to the appended claims and as the following detailed description proceeds in reference to the figures of drawing wherein:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a portion of a sewing machine showing one form of cutting apparatus according to the invention applied thereto; and
FIG. 2 is a view in side elevation of a modified form of cutter and protective guard.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawing, FIG. 1 shows a portion of a sewing machine including a conventional base plate 10 which defines a horizontal work surface generally indicated by numeral 11 that serves in a known manner for supporting workpieces as they are caused to advance to the stitching zone beneath the machine's presser foot 12. The presser foot 12 along with the machine's needle that is depicted by numeral 14 are supported in a conventional manner by the free end of an arm 13 that forms a part of the supporting frame of the machine. Downstream of the stitching zone, which is in the direction of the indicating arrow X in FIG. 1, the work surface 11 is provided with an opening 15 which traverses the direction of travel of the workpieces as they leave the stitching zone. This opening 15 provides a means which permits an elongated movable cutting blade 16 to travel beyond the upper surface of the work surface 11. A counter-blade 17 is fixedly mounted in the opening 15 and is arranged to cooperate with the blade 16 to provide a scissor-like cutting action during the latter's intended function which will be further described hereinafter. Blade 16 is attached to one side of a support arm 18 that is pivotably supported on a shaft 19. This shaft 19 is supported in a bracket 20 that is mounted on the work surface 11. The support arm 18 is provided with an integrally formed and upwardly directed lug 21 having an elongated opening 22 through which a pin 23 carried in the bifurcated end of a piston rod 24 is caused to extend. Piston rod 24 forms a part of a piston-cylinder unit 25 which may be of the hydraulic or pneumatic type and reciprocating movement of said piston rod will by means of pin 23 moving within the limits of the elongated slot 22 cause the support arm 18 to pivot a preselected distance first in one direction and then the other. The pre-selected distance which the support arm 18 is caused to travel is sufficient to cause the blade 16 to cooperate with the counter-blade 17 and perform the necessary cutting action required for the particular workpieces which are advancing successively below the presser foot 12 and said blade 16. A protective guard 26 is disposed in operative association with the blade 16 and the embodiment shown in FIG. 1 has a configuration which is substantially U-shaped and is positioned so as to surround the danger areas of said blade 16. This protective guard is supported independently of the support arm 18 by means of aligned openings (not shown) adjacent the ends thereof which provide a means for pivtably supporting it on the shaft 19. By a means yet to be described the protective guard 26 can be lowered in timed sequence with the blade 16 from the raised position shown in FIG. 1 to a position whereat it provides positive protection against injury to an operator by said blade 16.
Referring again to FIG. 1 one end of the protective guard 26 is provided with an integrally formed and upwardly directed ear 28 having an elongated opening 29 through which a pin 30 is caused to extend. This pin 30 is connected to a piston rod 32 of a second piston-cylinder unit 33 of the double acting type and is adapted to control the movements referred to above of the protective guard 26. A cam element 34 is assembled on one end of shaft 19 by means of a set screw 35 and is disposed in contiguous relation with one side of the protective guard 26. This cam element 34 is provided with a projecting finger 36 and during the lowering of the protective guard 26, said finger 36 is caused to pivot upwardly until it engages a plunger 37 of a switching relay 38 which when actuated, provides a signal to initiate actuation or the lowering of the blade 16 by the piston-cylinder unit 25. In other words, the protective guard 26 can be lowered manually by the operator or by a suitably timed automatic device on the machine and when it reaches a position where there is no possibility of an operator coming in contact with the blade 16, the finger 36 of the cam element 34 is then and only then effective in initiating actuation of said blade 16 by its engagement with the plunger 37 of the switching relay 38. The switching relay 38 is fixedly mounted as are the piston-cylinder units 25 and 33 relative to the work surface 22 and engagement of the plunger 37 by the finger 36 can be timed to occur at the lower end of the path of travel of the protective guard 26 or just prior thereto provided the signal for the actuation of the blade 16 is only given when said guard has travelled a sufficient distance to provide maximum safety for the operator. Movement of the blade 16 and the protective guard 26 to their initial or inactive positions can occur simultaneously or may be accomplished by a sequence reverse to that by which they were activated. The manner in which the protective guard 26 and blade 16 are actuated provide positive assurance of safety for the operator and when these elements are in their inactive positions, sufficient clearence is provided so that the workpieces are cuased to advance on the work surface 11 free of any possible interference.
Referring now to FIG. 2, a modification of the cutting apparatus according to the invention is shown in which a cutting blade 40 of the circular type is utilized and which is driven by any suitable motor indicated by numeral 42. This blade 40 is lowered and raised by means of a piston-cyliinder unit 43 in a manner which has not been shown in detail for it is considered that the mechanism for performing such a function is well known. Additionally, the motor 42 may be of the type which operates continuously or that is actuated when the blade is lowered to perform its intended function. As shown in FIG. 2 the blade 40 is provided with a protective guard having a depending and substantially U-shaped frame 44 with side walls 45 (one only shown) which are preferably formed from a suitable transparent material and mounted on said frame so as to prevent accidental contact with said blade. The frame 44 is mounted on guides 46 provided on a fixed support member 47 which enables it to be moved either in an upwardly or downwardly direction as shown by the indicating arrow Y. This movement is perpendicular to the work surface indicated by numeral 48 and is accomplished by means of the piston rod of a pneumatic cylinder 49. The signal for initiating the lowering of the blade 40 is provided by a plunger 50 which forms a part of a pneumatic valve 51 that is mounted on the frame 44. When the plunger 50 is depressed by a means yet to be described, the valve 51 is opened and permits fluid from a supply line 52 to flow through a feed line 53 to the piston-cylinder unit 43. The plunger 50 is depressed or actuated by means of an abutment 54 fixedly mounted on the support member 47.
The means for mounting this abutment 54 include a pair of spaced and parallel openings 55 therein and through which locking screws 56 extend. These openings 55 provide a means for selectively positioning the abutment so that it will engage the plunger 50 at the most desirable time to effect the lowering of the protective guard prior to the lowering of the blade 40. The protective guard is lowered a pre-selected distance prior to providing a signal for actuating the blade 40 so that the necessary precautionary measures are had to prevent possible contact with said blade by the operator. The blade when lowered is caused to extend a limited amount into a slot (not shown) provided in the work surface 48.
In their raised or inactive positions, the protective guard and the blade 40 are at a sufficient distance above the work surface 48 so that the workpieces are capable of advancing without interference.
Although the present invention has been described in connection with a preferred embodiment and a single modification thereof, it is to be understood that other modifications and variations may be resorted to 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 invention and the appended claims. | The invention pertains to a cutting apparatus for sewing machines disposed downstream of the machine's sewing zone. The apparatus includes a cutting blade and a protective guard for the blade both of which have independent actuating devices. The actuating devices are effective in moving the guard and blade between one position which provides clearance for the workpieces being advanced along the machine's work surface and another position where they are operatively associated with the workpieces. A timing element is operatively associated with both actuating devices and is effective in causing the protective guard to be moved toward the workpieces prior to movement of the blade. | 3 |
FIELD OF THE INVENTION
The present invention relates to a communication system which enables simultaneous two-way transmission in the same spectrum and is particularly adapted for use in two-wire telephone subscriber carrier applications.
BACKGROUND OF THE INVENTION
Economic factors dictate the use of multi-party lines under circumstances where, as in some rural areas, there are a limited number of subscribers in a given locale. This multi-party approach provides for the use of one pair of wires by many customers and can be accomplished by the use of party lines or the use of prior art subscriber carrier systems wherein each subscriber is assigned a particular frequency spectrum for his transmitter and another spectrum for his receiver. The obvious advantage of the subscriber carrier approach is that each subscriber can use his telephone independently of others using the same pair of wires, thereby providing private service over the shared wires. In general, prior art subscriber carrier systems utilize a separate spectrum for transmitting and receiving for each subscriber. Thus, a five subscriber system requires ten spectral bands. Because of cable losses and crosstalk, the upper frequency is limited to about 150 KHz. Due to these constraints, for conventional systems now in common use, the number of subscribers is generally limited to about five to eight per pair of wires. Thus, in order to service twelve subscribers, two or three pairs of wires would be required.
The present invention concerns the provision of a system which enables transmission in both directions in the same spectrum and thus allows doubling of the number of customers as compared with conventional systems without the use of any additional lines. Thus, in this system, a five subscriber set-up requires five spectral bands only.
An approach developed independently of the present invention but bearing some broad similarity thereto is disclosed in U.S. Pat. No. 3,822,366 (O'Dea et al). This patent concerns a one channel carrier intercom system wherein transmission and reception take place in the same spectrum but not simultaneously. The system is intended for use by telephone men for conversation on an in-use physical pair of wires, rather as a full carrier system. The carrier is sent to the receiver by a simplex connection of the wire pair. The carrier is applied between ground and the wire pair so that the receiver recovers the carrier between the wire pair and ground, and recovers the signal across the pair. A diode ring acts as both the modulator and demodulator in this system. It will be evident from the description of the present invention set forth hereinbelow that the system of the present invention is quite different from that of the O'Dea et al patent.
SUMMARY OF THE INVENTION
A communication system is provided which, as noted above, can enable the transmission of twice as many channels over a given pair of wires, using the same bandwidth, as conventional telephone subscriber systems. Although the invention is particularly adapted for telephone subscriber application, the invention can also be applied to other communication systems as well.
According to a preferred embodiment, a two-wire carrier communication system is provided wherein, at a central station or unit, for each channel a transmit carrier and receive carrier are generated which are 90° out of phase, independently of the remainder of the system. The transmit modulator of each channel is connected to a hybrid which permits the transmit signal to drive the two-wire line while serving to isolate the central station receiver.
At each of the subscriber stations, the carrier, at its assigned frequency, is recovered and is used to demodulate the received signal. Moreover, after being phase shifted by 90°, the recovered carrier is modulated by the subscriber transmit signal. Each of the carriers received at the central station from the subscriber stations are delayed to align this carrier to the internal reference carrier. This delay is necessary to compensate for cable propagation delays which cause this received signal carrier to no longer be in quadrature to the central office transmit carrier. By maintaining the 90° phase difference between the transmitted and received carriers, interference is kept at a minimum.
A d.c. signal is advantageously added to the audio input signal for each channel in advance of the first station transmit modulator to ensure that its carrier is transmitted at all times.
Other features and advantages of the invention will be set forth in, or apparent from, the detailed description of a preferred embodiment found thereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic circuit diagram, in block form, of a preferred embodiment of a central station of the two-wire system data communication system of the invention;
FIG. 2 is a schematic circuit diagram, in block form, of a preferred embodiment of a subscriber station; and
FIGS. 3 and 4 are schematic circuit diagrams of two of the units of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, an embodiment of the central office station of the quadrature carrier system of the invention is shown. The central office station is part of an overall double sideband, amplitude modulation system. As noted above, in accordance with an aspect of the invention, the transmit carrier (sin w c t) and receive carrier (sin w c t+90) are 90° out of phase, independently of the remainder of the system.
The audio input to the central station is applied to an audio input terminal 10 and passes through a capacitor 12 to a low pass filter 14. Filter 14 is used to remove components of the audio input above 3 kHz. This determines the bandwidth of the subscriber carrier since, as explained below, balanced modulation with a sinewave carrier is used to generate the double sideband, amplitude modulated signal. The output of filter 14 is connected to a summer 16 which also receives a d.c. input applied to a d.c. input terminal 18. The d.c. component is added to ensure that the carrier is being transmitted at all times (less than 100% modulation).
The output of summer 16 is connected to a balanced modulator 20 which also receives a sin w c t carrier input from a master oscillator 22. The transmit carrier is basically the master carrier and all other carriers are slaved thereto. Modulator 20 is connected to a conventional hybrid 24 which permits the transmit signal to drive the two-wire telephone line, denoted 30, while minimizing the amount of the central office transmit signal that is actually "seen" by the central office receiver. Hybrid 24 is connected to two-wire line 30 through a bidirectional variable phase network 26 which is discussed hereinbelow.
The receive output of hybrid 24 is connected to a phase adjustment control circuit 32 which is also described below and which receives, as a second input, the sin (w c t+90°) output of master oscillator 22. The receive output of hybrid 24 is also connected to a balanced demodulator 34 which is also connected to a sin (w c t+90°) demodulating carrier signal from master oscillator 22. Balanced demodulator 34 is connected through a capacitor 36 and a low pass filter 38 to an audio output terminal 40.
Referring to FIG. 2, an embodiment of the subscriber station is shown which is adapted to cooperate with the central office station of FIG. 1. The station of FIG. 2 includes a hybrid 42 which is connected to the two-wire telephone line 30. Like hybrid 24 of the central office station, hybrid 42 is used to separate the transmit and receive signals that occur simultaneously on two-wire line 30.
Before proceeding with the description of FIG. 2, it should be noted that at both stations the amount of separation available is a function of how well the impedance of the hybrid matches that of the telephone line. Various types and sizes of wire are used for telephone lines and this necessitates the use of a variable impedance hybrid or a modulation scheme which is immune to the interference produced where there is a mis-match. The quadrature carrier modulation technique disclosed herein provides the required immunity so that the hybrids 24 and 42 do not have to be adjusted.
Thus, referring again to FIG. 2, the output of hybrid 42 is connected to the input of a balanced demodulator 46 and to the input of a phase locked loop 48. The output of phase locked loop 48 forms the second input to demodulator 46 and this output, shifted by 90°, forms the second input to modulator 44. The receiver branch, which includes demodulator 46, also incorporates a capacitor 50, and a low pass filter 52, the latter of which is used to reduce noise and the amount of interference from other frequency carriers. The output of filter 52 is connected to an audio output terminal 54. The transmitter branch includes an audio input terminal 56, a capacitor 58, a low pass filter 60 and a summer 62 having a d.c. input 64, and a balanced modulator 44. This subscriber station transmitter is similar to that of the central office station.
The subscriber station carrier is transmitted back to the central office through hybrid 42 and two-wire line 30 to the central office hybrid 26 (FIG. 1). Because the demodulating carrier at the central office is locked at 90° to the central office transmit carrier, variable phase network 26 is adjusted to align the receive line signal to the carrier.
The system as a whole can perhaps be best understood if the carrier phase is considered at various points in the system. Thus, referring to FIGS. 1 and 2 together, the carrier at the central office transmitter (the branch containing modulator 20) will be assigned the value sin w c t as noted above. Assuming that variable phase network 26 produces a delay , the transmit signal is of the form sin (w c t+ ) when entering line 30. Assuming a delay in line 30 of the value θ, the carrier received at the subscriber station is of the form sin (w c t+ +θ). As noted above, this signal is phase shifted 90° in phase locked loop 48 to produce the transmit carrier for the subscriber station (the input to modulator 44) and thus is 90° out of phase with the receiver carrier. After passing back through telephone line 30, the received input to variable phase network 26 is of the form sin (w c t+ +2θ+90°) and at the output thereof is of the form sin (w c t+2 +2θ+90°). Phase adjustment control circuit 32 thus is utilized to adjust the delay of variable phase network 32 such that
2 +2θ=180 N
where N is a positive non-zero integer (N=1,2,3, . . . ). Since the value of θ is fixed by the particular telephone line used, the delay of variable phase network 32 is varied until the foregoing equation is satisfied. Under these circumstances, the receive carrier at the central office station is 90° out of phase with the transmit carrier and hence interference is a minimum.
Although the units of the system of FIGS. 1 and 2 could be readily implemented by one skilled in the art based on the functions they are to perform, the make-up of several of these units will be considered for purposes of completeness. Thus, referring to FIG. 3, a exemplary embodiment of hybrid 24 is illustrated. As illustrated, hybrid 24 can take a form of a duplexer circuit comprising an operational amplifier 67 and associated resistors 65, 69 and 66 and capacitor 68. Hybrid 24 is connected to variable phase network 26 (and thence to transmission line 30) from a point on the junction between resistor 69 and the non-inverting input of operational amplifier 60. A similar duplexer circuit is disclosed in "Electronic Design", Jan. 4, 1975, pp. 76 to 77 and reference is made to those pages for a more complete description of the circuit.
Variable phase network 26 can conveniently comprise a variable capacitor connected in parallel with a pair of inductances, with a point on the junction between the inductances being connected to ground through the series combination of a capacitor and inductance. Network 26 can obviously take other forms as well.
An exemplary embodiment of phase adjustment control circuit 32 is illustrated in FIG. 4. Control circuit 32 basically comprises a phase comparator 70, which may be an RCA type CD4046A, and a low pass filter and offset circuit formed by shunt filter capacitors 72 and 74, series resistors 76 and 78, and operational amplifier 84 together with associated capacitor 82, resistors 86, 88 and potentiometer 90. Adjustment is provided by potentiometer 90.
Although the invention has been described relative to exemplary embodiments thereof, it will be understood that other variations and modifications can be effected in these embodiments without departing from the scope and spirit of the invention. | A two-wire, carrier-type communication system is provided which enables simultaneous two-way transmission over two-wire circuits in the same spectrum. Carrier signals in quadrature are used to allow separation of signals within the same frequency spectrum. The carrier recovered at each subscriber station is used to demodulate the received signal and, after being phase shifted 90°, is applied as carrier to the transmitter modulator. The transmitters at the subscriber stations are thus the same as that at the central office but are locked to the receiver and 90° out of phase. A bidirectional control phase adjustment network at the central station adjusts the phase of the signal received thereby until the received carrier is 90° out of phase with the transmit carrier. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a novel and improved material useful as a building sheet material, such as roofing shingles, siding or the like. More particularly, this invention relates to a bituminous sheet material comprising an inorganic fiber mat substrate saturated with a bituminous composition, which sheet material possesses improved physical properties for handling and durability, particularly in lower temperature environments.
Bituminous sheet materials, such as roofing felt or shingles which are useful in sealing exterior building surfaces, are generally composed of a support layer or substrate, traditionally a felted, fibrous membrane which is saturated with a water-proofing agent, such as an asphalt or bituminous composition. While the asphalt or bitumen is still in a plastic state, granular materials which are opaque to ultraviolet light are ordinarily pressed therein on the weather-exposed face to protect the bitumen from the ultraviolet rays or actinic effects of the sun, as well as to form a decorative coating. The granular material further acts to protect the asphalt or bitumen coating which would otherwise deteriorate producing cracking or crazing, thus permitting leaking of the roof or siding surface in due time. The granules which have been most widely used are formed from rock, such as crushed slate and trap rock.
The felted fibrous substrate or membrane has been most commonly formed of rag, wood, paper, jute or other organic fibers on a machine similar to that used for manufacturing paper. The felt material is impregnated with asphalt, generally a blown petroleum derivative, by immersion, flowing, spraying, roller coating, or by a combination of such treatments, with excess saturant removed by scraping. The waterproofing character of the asphalt is the main attribute of the final product and the felt serves in a secondary status as a carrier, substrate and preserver of the asphalt.
While sheet materials based on organic felts possess excellent flexibility and tensile properties for good handling characteristics, they tend either to absorb or release moisture under varying climatic conditions. The resulting fluctuations in moisture content cause the felt to expand and contract, which often results in the occurrence of blisters due to steam occlusions. Organic fibers used in making suitable felt materials also tend to decay somewhat rapidly under variations in weather conditions and have drawbacks for other reasons, such as heat and hydro-dimensional instability which lead to distortions in the applied finished product.
Accordingly, it has been desirable to use inorganic fibers in preparing roofing felts, and particularly glass fibers, since such fibers possess excellent thermal and chemical stability. The desirability of an inorganic or glass fiber based felt is due to its peculiar properties and characteristics, including fire-resistance, low thermal expansion and contraction, insensitivity to relative humidity changes, and resistance to moisture absorption.
While glass fibers are more weather resistant then organic fibers, glass fiber mat based shingles coated or impregnated with a bituminous material have heretofore had serious application and handling problems, particularly when installed at or below a field ambient temperature of 40° F. (4.5° C.). Moreover, the inherent brittleness of most inorganic or glass fiber mat materials, which is less of a problem in milder climates, makes the product totally unsuitable in colder climates.
While glass fiber mat of better quality, particularly as to flexibility, may be prepared from continually drawn glass fibers cut from higher quality glass staple fiber, the cost of any resulting product increases significantly. To keep costs at an acceptable level, less expensive glass fibers and other inorganic fibers, such as glass wool and rock wool are desirable. However, inorganic fibers other than glass are even more brittle and flexibility is further impaired.
A number of attempts have been made to improve the flexibility, durability, and handling characteristics of inorganic fiber based mat products. The flexibility of such products can be enhanced by use of a special flexible glue or binder, but the resulting product has been found to have considerably lower breaking or tensile strength. Since glass fiber mats are composed of glass fibers held together by a binder material, attempts have been made to produce glass fiber mat having improved tensile strength and flexibility by varying the binder composition. A multitude of compositions comprising the asphalt or bitumen component combined with elastomer and thermoplastic polymer ingredients have been used as binders, but unfortunately, all have heretofore been deficient in one or more respects.
Bituminous coating or binder materials suitable for most roof service conditions have a glass transition point of approximately 32° F. (0° C.). Commonly, the bituminous materials are filled with an inorganic mineral stabilizer to improve their fire resistance, high temperature flow and weather resistance. These filled bituminous coatings, however, have a distinct tendency to shatter and break during normal application or handling or during maintenance traffic on the roof shingle surface. In particular, such binder materials provide glass mats which exhibit only acceptable tensile strengths at room temperature and at lower temperatures. Furthermore, the tensile strengths of such mats deteriorate appreciably when the mats are subjected to wet conditions, which can be encountered in their use in roofing as well as in siding or flooring products. In addition, these prior art mats have relatively poor flexibility resulting in buckling, creasing or cracking of the mats during use, handling or application as a base in asphalt roofing shingles or as a backing felt or base support for other sheet uses.
Accordingly, it is an object of the present invention to provide an inorganic fiber based mat composition, particularly, a glass fiber mat roofing felt, having improved flexibility, tensile strength, durability and handling properties, particularly at lower temperatures.
It is another object of this invention to provide an all weather glass mat based bituminous roofing felt which has acceptable physical properties, including flexibility and tensile strength, at both high and low temperature extremes, and which is capable of withstanding the stresses imposed by an outdoor environment, particularly the mechanical stresses due to the motion of the surface on which it is applied, natural atmospheric stresses (due to temperature, sun and the like) and artificial stresses, such as chemical and physical attacks.
SUMMARY OF THE INVENTION
It has now been found that the performance of any inorganic fiber based substrate used in the manufacture of building sheet products, particularly roofing shingles, can be remarkably improved in its application and end use in both high and low temperature environments, where the fibrous substrate or layer is first pre-coated with a polymer/bitumen composition prior to the application of any conventional asphalt or bitumen top coating composition. The product so manufactured can be stored and then applied at temperatures as low as 0° F. (-14° C.), depending upon the level of polymer modification selected. It has been found that the polymer/bitumen pre-coat acts upon the fiber substrate in such a way that the composite shingle exhibits improved cold weather handlability, and improved tear resistance and resistance to wind blow-off at low temperatures. As a result, the flexibility and tensile properties of the resulting mat or sheet product are enhanced, particularly for application and use in colder climates.
The polymer content of the bitumen/polymer precoat composition can range from about 3% to about 99%, preferably 10 to 20%, by weight with the remainder being a properly selected bituminous material. The polymer materials which are suitable for use in the invention may include many polymers, such as polyethylene vinyl acetate, poly (styrene butadiene-styrene) (SBS), poly (atactic) propylene (APP), and other elastomers and blends of these polymers that have sufficient thermodynamic compatibility with asphalt so as not to exhibit phase separation upon heated storage, but which impart their elastomeric characteristics to the asphalt without excessive viscosity increases.
As previously stated, the low temperature properties of the mat depend directly upon the polymer content of the precoat composition. The amount of elasticity, toughness, tenacity, flexibility, etc. arises from the rubber. Increased rubber content leads to an increase in these properties. As the polymer content of the pre-coat composition is increased, the percent elongation, impact resistance, toughness and tenacity are increased.
In the context of the present invention, all bituminous asphalt and coal tar materials are contemplated for use in the pre-coat composition, including "straight run" bitumens, which comprise the residual portion remaining after vacuum distillation of the petroleum, as well as oxidized bitumens obtained by blowing air at elevated temperatures through the asphalt.
Asphalt shall be selected such that when compounded with polymer, the viscosity will be low enough at application temperatures to penetrate the mat (approximately 500 centipose). The asphalt shall contain sufficient solubilizing oils to prevent gross phase separation of the uniformly dispersed rubber.
The polymer/bitumen pre-coat composition according to the invention is applied at a rate of about 0.75 lbs. to 17 lbs. per 100 feet, preferably about 9 lbs. to 11 lbs. per 100 square feet. The rate depends upon the market area to be served (i.e. climate), the nature of the filled coating asphalt and the flexibility, toughness and elasticity of the mat base.
The pre-coat composition of the present invention may be advantageously applied to all inorganic fiber substrates, but is most preferably applied to glass fiber mat. Other inorganic fiber materials which have been useful in preparing building mat or sheet material include mineral wool or rock wool. The glass or other inorganic fibrous material may comprise fibers of varying lengths and diameters, but most preferably 1/4" length to 3" in length, 1 micron to 50 microns in diameter.
The pre-coat may be applied to the substrate in any known way, such as hot melt saturation.
Roof shingle mat prepared according to the invention exhibit the following advantageous properties:
A. Foldability in the cold, i.e. no cracks at temperatures as low as -20° Centigrade (-4° F.).
B. Elongation at break of about 3% to 100%.
C. Thermal behavior: after 5 hours at 190° Centigrade (374° F.), or below foldability in the cold are unchanged.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the invention pertains to a wet lay process for preparing a glass fiber mat based roofing shingle using the pre-coat composition and technique of the present invention. It will be understood that other processes known in the art, such as a dry lay process, may be used as well, as may other inorganic fibers for other similar end uses. Furthermore, the description is made using chopped bundles of glass fibers, although other forms of glass fiber, such as continuous strands may be used.
A glass fiber mat is formed by conventional wet lay process techniques using chopped bundles of glass fibers having a length of about 1/4 inch to 3 inches and a diameter of about 10 to 20 microns. The bundles are added to an aqueous dispersant medium to form an aqueous slurry. Any suitable dispersant known in the art such as Katapol VP 532, may be used. The fibrous slurry is then agitated to form a workable dispersion at a suitable consistency and is thereafter passed to a mat forming machine. En route to the screen, the dispersion is diluted with water to a lower fiber concentration.
The fibers are collected at the wire screen in the form of a wet fiber mat and the excess water is removed by vacuum in the usual manner. Binder is applied and the wet mat is then dried and binder cured for application of the pre-coat composition. The precoating is accomplished by hot melt application on the roofing machine just prior to the final coating. In preparing the roofing shingle material, the pre-coated glass mat based substrate is then topcoated with a standard shingle binder coating comprising coating asphalt (190°-240° F. softening point) and mineral stabilizer.
The invention may be further understood by reference to the following examples, which are provided to illustrate the invention and should not be construed to limit the many variations and substitutions which may be made within the scope of the claims.
EXAMPLE 1
Preparation of Polymer/Bitumen Pre-Coat Compositions
Fifteen percent by weight of Phillips Solprene 475S (10% rubber, 5% oil) was added to saturant asphalt (130° F. R&B softening point, 62 dmm penetration 77/100/5). Agitation of the asphalt/polymer mix was accomplished by counter rotating vanes attached to a central spindle. A gas fired burner was used at the outside bottom of the tank to maintain temperature between 370° F. and 410° F. Mixing was accomplished in 45 minutes.
The elastomer pre-coating was discharged by gravity, spread across the moving glass mat and applied at a rate of 9 lb. to 13 lb. per 100 square feet to conventional glass mat.
EXAMPLE 2
Preparation of Roofing Shingles
The precoated glass mat (Example 1) was surfaced on both sides with a sand/talc mixture, cooled, and rolled into 180 ft. lenghts. Subsequently, this material was utilized to manufacture shingles in the usual manner. The 180 ft. length rolls were spliced into the roofing line and coated with a filled coating asphalt, surfaced, cooled, cut & packaged.
EXAMPLE 3
Physical Testing
Five samples of the roofing shingle material prepared in accordance with Example 2 using the pre-coating of Example 1 were:
1. Placed into a climate test chamber, controlled to a temperature of 40° F. and at the end of the 24+ hours period, and also at the end of a 48+ hours period, sample shingles were manipulated by several independent observers and compared, subjectively, for flexibility, stiffness, brittleness, and tearing propensity with that obtained on shingles manufactured using the standard construction on glass mat. All of the observers detected a vast improvement in each of the characteristics over the standard glass mat based shingle.
Segments of the above conditioned materials were subjected to a standardized cold temperature flexural bend test. The experimental material out performed the standard glass mat shingle by a factor of two.
Test decks were constructed and conditioned at 40° F. These decks were placed in a "wind tunnel" and tested for 15 minutes at 40° F. under an air stream with a velocity up to 60 miles per hour. The standard glass mat bituminous shingles failed by loss of tabs, while the invention product remained intact.
EXAMPLE 4
Long-Term Weatherability Tests
About 250 samples of the roofing shingle material prepared in accordance with Example 2 again using the precoat formulation of Example 1 were tested for long term weatherability as follows:
Standardized roofing test deck panels were constructed and placed in a controlled exposure area (Weathering Farm) at a 45° angle facing south, south west in the Houston, Tex. area. These materials are in excellent condition after almost two years exposure.
Standardized shingle roofing test deck panels were constructed and placed on exposure in an industralized north east, U.S.A. urban area. These shingles are in a good condition compared to control shingles.
An experimental production trial run at the subject material was shipped to St. Paul, Minn. and stored in an unheated warehouse. When thoroughly cold (exterior temperatures were from -30° F. to 20° F.), the shingles were applied to a building's roof by a commercial roofing applicator. The temperature at time of application hovered around 5° F. The experimental shingles were applied with no problems and were vastly superior, in application performance, to standard glass mat based bituminous shingles.
While the invention has been described with reference to certain embodiments thereof, it will be understood by those skilled in the art that other obvious embodiments as well as certain changes and modifications within the scope of the teachings of this specification are contemplated. Accordingly, the invention shall be limited only by the proper scope of the appended claims. | An improved inorganic fiber based roofing shingle for use in both high and low temperature environments is prepared by pre-coating an inorganic fibrous substrate with a polymer/bitumen composition prior to the application of a conventional asphalt or bitumen top coat, wherein the polymer content of the bitumen/polymer pre-coat composition ranges from about 3 to 99% by weight. | 8 |
BACKGROUND OF THE INVENTION
The present invention is directed to a vehicle frame and, more particularly, to a bicycle, tricycle or motorcycle frame capable of storing compressed gas inside the frame members thereof.
Vehicles driven by human power, such as bicycles, motor-assisted bicycles, and tricycles, have a frame and wheels that are rotatably supported by the frame and are mounted with air-filled rubber tires. In the case of a bicycle or motor-assisted bicycle, the frame usually comprises tubes made of metal or synthetic resin, and a space is formed on the inside of the frame. With a bicycle, for instance, a shift apparatus, a brake apparatus, or the like can be operated by using a pneumatic device that is lightweight and easy to operate. Of course, such devices usually require a compressed air source to operate them. In the case of a vehicle that is large and has a motor, such as an automobile, an air compressor can be mounted on board, but the installation of such a large compressed air source is a difficult proposition with a vehicle that is small, lightweight, and human-powered, such as a bicycle. When an gas actuated devices are used with a bicycle, it is possible to mount a small gas cylinder filled with liquefied gas, for example, on the bicycle. With bicycles that need to be lightweight, however, the installation of a small gas cylinder is a problem in that the weight of the cylinder makes the bicycle that much heavier. Light weight is a concern common to all vehicles driven by human power, and not just bicycles, and reducing the weight allows the running performance of the vehicle to be enhanced. Even if weight were not a problem, however, another problem with the use of a gas cylinder that has been charged with carbon dioxide or another liquefied gas as the compressed gas source is the difficulty of recharging the gas cylinder with gas when it runs out. This means that expensive gas cylinders have to be kept on hand at all times.
SUMMARY OF THE INVENTION
The present invention is directed to a vehicle frame having a construction with which compressed gas can be obtained easily and inexpensively in a bicycle or another such vehicle without increasing the weight of the vehicle. In one embodiment of the present invention, a vehicle frame is constructed of a frame body including a head component for supporting a front wheel, a seat supporting component for supporting a seat, and a frame component coupled to the head component and to the seat supporting component. The frame component defines a sealed space that is hermetically sealed from the head component and the seat component. The frame component includes a gas opening disposed on a side surface thereof and displaced from the head component and the seat component so that the sealed space may be charged with a compressed gas. If desired, the frame component may include a separate opening for supplying compressed gas to another component mounted on the bicycle.
In a more specific embodiment, the frame component is constructed of a down tube extending downward and rearward relative to the head component, a top tube extending rearward relative to the head component above the down tube, a seat tube disposed in an intermediate location relative to the seat supporting component and the bottom bracket component, a seat stay that forks downward and rearward relative to the top tube, and a chain stay that forks rearward relative to the bottom bracket component. In this case the sealed space is disposed within at least one of the down tube, the top tube, the seat tube, the seat stay and the chain stay. To maximize the storage capability of the vehicle frame, the interior spaces of the down tube, the top tube, the seat tube, the seat stay and the chain stay may be in fluid communication with each other for defining the sealed space.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a bicycle which incorporates a particular embodiment of a vehicle frame according to the present invention;
FIG. 2 is a partial cross sectional view of the vehicle frame shown in FIG. 1;
FIG. 3 is a schematic diagram of a gas actuated derailleur system that may be used in the bicycle shown in FIG. 1;
FIG. 4 is a schematic view of a gas actuated cleaning device that may be used in the bicycle shown in FIG. 1;
FIG. 5 is a schematic view of a lubricating device that may be used in the bicycle shown in FIG. 1; and
FIG. 6 is a schematic view of a gas controlled suspension mechanism that may be used in the bicycle shown in FIG. 1.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In FIG. 1, an MTB type of bicycle to which an embodiment of the present invention has been applied is equipped with a diamond-shape frame 1 that makes up the skeleton of the chassis. The frame 1 has a frame body 2 consisting of a front triangle and a rear triangle, and a front fork 3 that is rotatably supported around a diagonal vertical axis by the front portion of the frame body 2 and that is equipped at its lower portion with two pneumatic suspensions 3a. The bicycle comprises a handle component 4 that is linked to the front fork 3, a drive component 5 that is attached to the lower portion of the frame body 2 and that converts pedaling force into drive force, a front wheel 6 that is detachably mounted to the lower end of the front fork 3, a rear wheel 7 that is detachably mounted to the rear end of the frame body 2, and front and rear brakes 8 and 9.
As shown in FIG. 2, the frame body 2 has a head component 10 that rotatably supports the front fork 3, a bottom bracket component 11 that is used to rotatably support a bottom bracket axle (not shown), a saddle fixing component 12 that is used to fix a saddle (discussed below), and tube frame members 13 that link the components 10 through 12. These components are manufactured by the welding of metal tubes composed of aluminum, chrome-moly steel, a titanium alloy, or another such material.
The tube frame members 13 comprise a down tube 15, a top tube 16, a seat tube 17, a seat stay 18, and a chain stay 19. The down tube 15 extends diagonally downward and rearward from the head component 10, and the bottom bracket component 11 is provided to the rear end of the down tube 15. The top tube 16 extends rearward from the head component 10 above the down tube 15. The seat tube 17 links the rear end of the top tube 16 with the rear end of the down tube 15. The cylindrical saddle fixing component 12 is fixed by welding to the rear portion of the seat tube 17. As shown in FIG. 1, a seat post 29a, to the upper end of which is fixed a saddle 29b, is fixed to this saddle fixing component 12 such that its vertical position can be adjusted. The seat stay 18 extends in a two-forked branch downward and rearward from the rear end of the top tube 16. The chain stay 19 extends in a two-forked branch rearward from the bottom bracket component 11 and is linked to the rear ends of the seat stay 18.
The insides of these tube frame members 13 are hermetically sealed off from the outside, and the spaces inside adjacent tubes communicate with each other and constitute a gas-charging component 20 that is capable of storing less than about 10 kg/cm 2 compressed air at the most. Here, the internal spaces of the down tube 15 and the top tube 16 communicate at the portion to the rear of the head component 10, while the internal space of the seat tube 17 communicates with those of the top tube 16 and the down tube 15 at the upper and lower ends, respectively, of the seat tube 17. The internal spaces of the top tube 16 and the seat stay 18 communicate via a communication hole 18a formed in the rear portion of the top tube 16, and the internal spaces of the down tube 15 and the chain stay 19 communicate at the upper portion of the bottom bracket component 11.
The upper surface of the top tube 16 is provided with a gas charging opening 21 that is used to charge the gas-charging component 20 with compressed gas, and two gas supply openings 22 that are used to supply the compressed gas stored on the inside to the outside. The gas charging opening 21 is provided to the rear portion of the top tube 16. A U.S. type of tire valve (schrader valve), for example, is mounted to the gas charging opening 21, and this construction allows compressed air to be charged easily by means of a bicycle air pump or an automobile air pump. The two gas supply openings 22 are provided in parallel in the longitudinal direction to the front portion of the top tube 16. A pressure gauge 23, which is used to display the base pressure inside the gas-charging component 20 and to display the amount of remaining gas, is mounted to one of the gas supply openings 22, and a pressure regulator 25, which is equipped with a pressure gauge 24, is mounted to the other of the gas supply openings 22. Air tube support rings 26 are provided at suitable intervals from the top tube 16 to the lower portion of the seat stay 18. In addition, a seat 27 that is used to mount a rear brake 9 is formed somewhere along the seat stay 18, and a bracket 28 that is used to mount a front derailleur (discussed below) is formed at the rear portion of the lower end of the seat tube 17.
As shown in FIG. 1, a handle stem 30, which constitutes the handle component 4, is fixed to the upper portion of the front fork 3. A handlebar 31 that extends to the left and right is fixed to the upper end of the handle stem 30. End bars 32 are mounted to the ends of the handlebar 31. Grips (not shown) are mounted on the inner side of the end bars 32. A brake lever 33 and a pair of shift valves 34a and 34b that is used to shift the derailleur 39 is attached on the inside of one of the grips. These shift valves 34a and 34b are normal close manual valves that have levers, and only allow air to pass through when the lever is operated. A pair of shift valves 34c and 34d is also provided to the distal end of one of the end bars 32. The shift valves 34a and 34c are used to shift from a higher gear to a lower gear, while the shift valves 34b and 34d are used to shift from a lower gear to a higher gear. As a result, the rider can shift the derailleur 39 on an uphill stretch, for example, while still gripping the end bars 32, that is, without taking his or her hands off the end bars 32. A brake lever (not shown) that is equipped with a shift lever for shifting a front derailleur (discussed below) is attached on the inside of the other grip.
The drive component 5 has a gear crank component 35 that is provided to the bottom bracket component 11, a hub cog component 36 that is attached to the free hub of the rear wheel 7, a chain 37 that goes around the gear crank component 35 and the hub cog component 36, a front derailleur 38 and a rear derailleur 39 that are used for shifting gears, and a shift operating mechanism 40 that is coupled with the rear derailleur 39 and an operating cable 44 (FIG. 3) and that is used to move the derailleur 39 reciprocally one gear at a time in the hub axle direction.
The gear crank component 35 has a right gear crank 42 and a left crank (not shown), to the distal ends of which are attached pedals 41. The right gear crank 42 and the left crank are coupled by a bottom bracket axle. The bottom bracket axle is rotatably supported by a the bottom bracket component 11. Three chainwheels, for example, with different numbers of teeth are mounted to the right gear crank 42 such that they are parallel in the bottom bracket axle direction. Eight hub cogs, for example, with different numbers of teeth are mounted to the hub cog component 36 such that they are parallel in the hub axle direction.
The front derailleur 38 has a chain guide component 43 composed of a pair of plates that guide the chain 37 in the direction parallel to the chainwheels in the gear crank component 35, and a link mechanism (not shown) that is used to rotatably support the chain guide component 43 generally parallel to the chainwheels with respect to the frame 1. The front derailleur 38 is coupled to a shift lever that is attached to the handlebar 31 via a cable.
As shown in FIG. 3, the rear derailleur 39 has a chain guide component 45 having two sprockets that guide the chain 37 in the direction parallel to the hub cogs while applying tension to the chain 37, and a link mechanism 46 that is used to rotatably support the chain guide component 45 in the hub cog parallel direction with respect to the frame 1. The link mechanism 46 is fixed by a screw to a rear fork end 19a, and is biased by a spring 47 so that the chain guide component 45 is moved to the higher gear side.
The shift operating mechanism 40 is a type actuated by air, and has two air cylinders 50 and 51 and an operation component 52 that is operated by the air cylinders 50 and 51 and that is used to operate the rear derailleur 39. The operation component 52 has a swinging main arm 53 that is coupled to the air cylinder 50, a swinging release arm 54 that is coupled to the air cylinder 51, and a cable winder 57 that winds around its outer periphery the inner cable 44a of the operating cable 44. The cable winder 57 is designed to rotate in conjunction with the main arm 53, and a plurality of ratchet teeth 56 are formed around the outer periphery at specific intervals in the circumferential direction according to the parallel spacing of the hub cogs. A stop pawl 58 that engages with the ratchet teeth 56 is positioned on the outer peripheral side of the cable winder 57.
The air cylinders 50 and 51 are single-throw cylinders that each has a return spring on its inside, advance by a specific stroke when compressed air is supplied to supply openings 50a and 51a, and return to their home positions when this supply is stopped. The action of a single stroke of these air cylinders 50 and 51 causes the main arm 53 and the release arm 54 to swing by a specific angle back to their home positions. The swing and return of the main arm 53 by a specific angle causes the cable winder 57 to rotate in the cable winding direction by one ratchet tooth 56. This rotation causes the inner cable 44a of the operating cable 44 to be pulled in the direction of the arrow A, and causes the rear derailleur 39 to move to the lower gear side. As soon as the release arm 54 swings back in place, the stop pawl 58 instantly retracts from the ratchet teeth 56. As a result, the cable winder 57 rotates in the cable play-out direction by one ratchet tooth 56. This reverse rotation causes the inner cable 44a of the operating cable 44 to be played out in the direction of the arrow B, and causes the rear derailleur 39 to move to the higher gear side.
An air control component 60 is positioned between the gas-charging component 20 and the air cylinders 50 and 51. The air control component 60 has the four shift valves 34a through 34d, and shuttle valves 61a and 61b that are connected to the outlet side ports of the shift valves 34a and 34c and to the outlet side ports of the shift valves 34b and 34d, respectively. The four shift valves 34a through 34d are normal close, three-port, manual valves that each have a lever, as mentioned above, and only connect the inlet ports to the outlet ports and allow air to pass through when the lever is operated. When the lever is released and return to its home position, the outlet side port is connected with the exhaust port, and the air in the system is let out from the outlet side port on down.
The inlet side ports of the shift valves 34a through 34d are connected to the regulator 25, and the exhaust ports open to the outside. The shuttle valve 61a (or 61b) is provided so that one of the shift valves 34a and 34c (or 34b and 34d) will not leak air when the other shift valve 34c or 34a has been operated, and is provided in order to select the operation of either the shift valve 34a or 34c (or 34b or 34d). The outlet side ports of the shuttle valves 61a and 61b are connected to the supply openings 50a and 51a of the air cylinders 50 and 51, respectively. The various valves and cylinders are connected by air tubes.
The shifting of the bicycle rear derailleur 39 by means of the compressed air stored in the gas-charging component 20 will now be described.
Before the bicycle is to be used, the gas-charging component 20 is charged with compressed air. Here, for example, a U.S. tire valve adapter that is connected to a compressor for pumping air into automobile tires at a service station or the like is mounted to the gas charging opening 21. The gas-charging component 20 is then charged with about 5 to 8 kg/cm 2 of compressed air, for example. The supply pressure is adjusted to about 2 kg/cm 2 by the regulator 25. When the pressure on the pressure gauge 23 has dropped to 2 kg/cm 2 , for example, and is equal to the supply pressure, the compressed gas will not be output from the gas storage component 20. Therefore, in this case, compressed air must again be charged into the gas-charging component 20.
The lever of the shift valve 34a or 34c is operated one time when the rear derailleur 39 is to be shifted from a higher to a lower gear. When the shift valve 34a or 34c is operated one time, the compressed air that has been adjusted to about 2 kg/cm 2 by the regulator is supplied to the air cylinder 50 through the shift valve 34a or 34c and the shuttle valve 61a while the lever is held. At this point, a valve body 62a on the inside of the shuttle valve 61a is pushed by the compressed air in the direction opposite to the air supply direction, which prevents the back-flow of the compressed air into the outlet side port of the shift valve 34c or 34a on the reverse side.
When air is supplied to the air cylinder 50, the cylinder rod of the air cylinder 50 advances by a specific stroke and causes the main arm 53 to swing a specific angle. As a result, the cable winder 57 rotates in the cable winding direction by one ratchet tooth 56. This rotation causes the inner cable 44a of the operating cable 44 to be pulled in the direction of the arrow A, and causes the rear derailleur 39 to move to the lower gear side. When the lever is then released, the outlet side port communicates with the exhaust port, which releases the pressure of the air inside the air cylinder 50, and the cylinder rod is returned by its spring to its home position. As a result, the main lever 53 also returns to its home position. Meanwhile, the cable winder 57 maintains the position it occupies after being rotated by the engagement between the stop pawl 58 and the ratchet teeth 56.
When the rear derailleur 39 is to be switched from a lower to a higher gear, the lever of the shift valve 34b or 34d is operated one time. When the shift valve 34b or 34d is operated one time, the compressed air is supplied to the air cylinder 51 through the shift valve 34b or 34d and the shuttle valve 61b while the lever is held. At this point, a valve body 62b on the inside of the shuttle valve 61b is pushed by the compressed air in the direction opposite to the air supply direction, which prevents the back-flow of the compressed air into the outlet side port of the shift valve 34d or 34b on the reverse side.
When air is supplied to the air cylinder 51, the cylinder rod of the air cylinder 51 advances by a specific stroke and causes the release arm 54 to swing a specific angle. As a result, the stop pawl 58 instantly retracts from the ratchet teeth 56, and the cable winder 57 rotates in the cable play-out direction by one ratchet tooth 56. This rotation causes the inner cable 44a of the operating cable 44 to be released in the direction of the arrow B, and causes the rear derailleur 39 to move to the higher gear side. When the lever is then released, the outlet side port communicates with the exhaust port, which releases the pressure of the air inside the air cylinder 50, and the cylinder rod is returned by its spring to its home position. As a result, the main lever 54 also returns to its home position. Meanwhile, the cable winder 57 maintains the position it occupies after being rotated by the engagement between the stop pawl 58 and the ratchet teeth 56.
With the present invention, since the compressed gas is stored in the gas-charging component 20 inside the frame 1, compressed gas can be obtained without any increase in weight. Also, if a valve that fits an ordinary air pump is mounted to the gas-charging component 20, the gas-charging component can be charged with compressed air with ease, allowing compressed gas to be obtained easily and inexpensively. Also, charging the inside of the frame 1 with compressed air results in the frame 1 being reinforced by the compressed air, which means that the rigidity of the frame 1 can be raised without any weight penalty.
FIG. 4 is a schematic view of a gas actuated cleaning device that may be used in the bicycle shown in FIG. 1. As shown in FIG. 4, an air nozzle 71 may be position in the vicinity of the brake arms of the front and rear brakes 8 and 9, and a manual valve 70 similar to the shift valves may be positioned between the regulator 25 and the air nozzle 71. In this case, operation of the manual valve 70 will cause the compressed gas that has been charged into the gas-charging component 20 to be sprayed from the air nozzle 71, allowing any dirt or other foreign matter that is clogging the gas-charging component 20 to be removed, and allowing the braking force of the brakes 8 and 9 to be kept constant. The position of the air nozzle 71 is not limited to the brakes 8 and 9, and can also be any other site where cleaning is required.
FIG. 5 is a schematic view of a lubricating device that may be used in the bicycle shown in FIG. 1. As shown in FIG. 5, an oiling nozzle 81 in which lubricating oil is stored may be positioned at the hub cog component 36 and at the gear crank component 35 of the drive component 5, for example, and a manual valve 80 similar to the shift valves may be positioned between the regulator 25 and the air nozzle 71. In this case, operation of the manual valve 80 will cause lubricating oil to be sprayed in a mist from the oiling nozzle 81 along with the compressed gas that has been charged into the gas-charging component 20, so that the gear crank component 35 and the hub cog component 36 are suitably lubricated. The spraying of the lubricating oil also allows any dirt or other foreign matter that is adhered to the gear crank component 35 or the like to be removed. The position of the air nozzle 81 is not limited to the gear crank component 35 and the hub cog component 36, and can also be any other site where lubrication is required.
FIG. 6 is a schematic view of a gas controlled suspension mechanism that may be used in the bicycle shown in FIG. 1. As shown in FIG. 6, a manual valve 90 similar to the shift valves may be positioned between the regulator 25 and the suspension 3a in order to adjust the air pressure of the suspension 3a. In this case, since the outlet side port of the manual valve 90 is connected to a normal close exhaust port, a check valve 92 is positioned between the manual valve 90 and the suspension 3a. Also, a pressure gauge 93 that displays the air pressure inside the suspension 3a is positioned between the check valve 92 and the suspension 3a. Furthermore, an exhaust valve 91 is positioned in tubing that branches off from between the check valve 92 and the pressure gauge 93 in order to lower the air pressure inside the suspension 3a. With this exhaust valve 91, the outlet side port is connected to the exhaust port by the operation of the lever, and at all other times the outlet side port is closed.
The operation of the regulator 25, the operation of the exhaust valve 91, and the operation of the manual valve 90 allow the gas-charging component 20 to be charged and the compressed gas to be adjusted and supplied to the suspension 3a, and allow the air pressure of the suspension 3a to be freely adjusted according to the road surface or other such factors, so that optimal suspension characteristics are obtained at all times. Also, with a bicycle that has a rear suspension, adjusting the pressure of the air in the rear suspension allows high-pressure air to be put into the suspension to make it more rigid and reduce pedaling loss on uphill stretches, and allows lower-pressure air to be put in on downhill stretches and optimize the suspension for downhill riding.
While the above is a description of various embodiments of the present invention, various modifications may be employed. For example, the applications of the compressed air charged into the gas-charging component 20 are not limited to the above embodiments, and all applications that require compressed air, such as the supply of air to the tires, are included. With the above embodiments, the gas-charging component 20 was charged with less than 10 kg/cm 2 of air because air is easy to handle and is less expensive, but the gas that is charged is not limited to air, and may instead be carbon dioxide, helium, or another such gas. The present invention is not limited to a bicycle frame, and can also be applied to any other vehicle frame that is driven by human power, such as a motor-assisted bicycle or a tricycle. The gas-charging component 20 may be divided into a plurality of sections according to the intended application and use. In this case, the system may be such that the various gas storage components 20 are coupled in series via check valves, for example, the charging of the gas begins with the gas-charging component furthest upstream, and when the pressure of the compressed air in the gas-charging components further downstream drops, these components are charged from the upstream side.
Thus, the scope of the invention should not be limited to the specific embodiments disclosed. Instead, the true scope of the invention should be determined by the following claims. | A vehicle frame is constructed of a frame body including a head component for supporting a front wheel, a seat supporting component for supporting a seat, and a frame component coupled to the head component and to the seat supporting component. The frame component defines a sealed space that is hermetically sealed from the head component and the seat component. The frame component includes a gas opening disposed on a side surface thereof and displaced from the head component and the seat component so that the sealed space may be charged with a compressed gas. If desired, the frame component may include a separate opening for supplying compressed gas to another component mounted on the bicycle. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims the priority of Provisional Application Serial No. 60/232,554, filed Sep. 14, 2000, in accordance with 35 USC §120.
FIELD OF THE INVENTION
The present invention relates to improved electronic circuits for the transmission of data between different clock domains. More particularly, the present invention relates to electronic circuits useful for the conformational representation of signals communicated between parts of circuits having different frequency clocks.
BACKGROUND OF THE INVENTION
Many electronic circuits and domains within circuits operate at rates which are determined by clock cycles generated at a particular domain clock frequency and transmitted to them. The term clock domain is used hereinunder to mean those parts of an electronic circuit that operate at the rate of a particular clock. These clock frequencies often vary among said clocks domains, varying accordingly the operating frequencies of the circuits in their domains. It is often necessary to generate a digital representation of the duration of a signal, expressed in terms of the number of clock cycles of its domain of origin, represented by signals of that domain frequency, and to transmit this digital representation to a destination clock domain, while converting the digital representation, generated by the origin domain clock, to that of the destination domain clock frequency.
In the past, when a signal needed to be transmitted from a fast clock domain to a slow clock domain, the signal would first need to be written by a processor from the fast clock domain to random access memory across a bus. Then a processor in the slow clock domain could read the signal across the bus from the random access memory at its own slow clock speed. However, this architecture and process requires a large number of read/write operations which directly affects the overall efficiency and performance of a system so designed.
SUMMARY OF THE INVENTION
The conversion of the transmitted digital representation of the number of clock cycles forming a signal from one clock domain frequency into another clock domain frequency, while retaining the number of cycles, is called hereinunder “conformation”.
As alluded to above, conformation poses problems, and particularly in the two following cases:
transmission of signal representation by slow clock signals (hereinbelow LF), i.e. long clock cycles, to a fast clock signal, short clock cycle domain (hereinbelow HF). In this case, some or all of the LF clock cycles may be sampled more than once by an HF domain device, leading to erroneous interpretation of the signal by the HF domain; and
transmission of signal duration representation by HF clock cycles to an LF domain. In this case, sampling of HF clock cycles by an LF clocked device may lead to erroneous interpretation of the signal as some of the short HF cycles will not be sampled by the LF device at all or an HF signal that is not a full integer multiple of LF cycles in length will be assigned an incorrect length by the LF device.
It is the purpose of the present invention to offer efficient circuits that overcome the aforementioned problems.
This is accomplished by the following two kinds of methods:
[1] For transmitting a data signal from a fast clock domain directly to a slow clock domain, a circuit, which bridges the two domains, detects the presence or absence of signal at every clock cycle in the fast domain, presence or absence being assigned a value, e.g. high vs. low (or 1 vs. 0) for each clock cycle. A plurality of the clock signal detection values is transmitted in parallel to a counter in the slow clock domain wherein each clock signal detection value is recorded as being a high or a low, and wherein the total number of detected high values or detected low values is output as a binary number by counter, thus informing the slow clock domain of the true number of clock cycles of which the signal is comprised; and
[2] For transmitting a data signal from a slow clock domain directly to a fast clock domain, a circuit which bridges the two domains comprises, in the slow clock domain, an edge detector for detecting the rising edge or falling edge of an incoming signal. When the edge detector detects a signal's leading edge, it causes the reversal of the state of flip-flops in both the slow domain and the fast domain, thereby signifying advent of a signal. Reversal of the flip-flops in the slow domain for each clock cycle when a signal is passing, is detected in the fast domain and understood by the fast domain as being caused by a new slow clock cycle, thereby sensitizing the fast clock domain to the beginning and ending of slow clock cycles which it would otherwise lump together as being a single clock cycle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a conformational timer circuit for the conformational representation of signals generated in a slow-clock domain and transmitted to a fast-clock domain;
FIG. 2 is a timing signal relationship diagram of the conformational timing circuit shown in FIG. 1;
FIG. 3 a is a block diagram of the fast-clock domain signal generating portion of a conformational timer circuit in accordance with an exemplary embodiment of the present invention;
FIG. 3 b is a block diagram of the slow-clock domain portion of a conformational timer circuit for processing signals generated in and transmitted from the fast clock domain shown in FIG. 3 a , hereinabove, in accordance with an exemplary embodiment of the present invention;
FIG. 4 a is a block diagram of the fast-clock domain signal generating portion of a conformational timer circuit in accordance with an exemplary embodiment of the present invention;
FIG. 4 b is a block diagram of the slow-clock domain portion of a conformational timer circuit for processing signals generated in and transmitted from the fast clock domain shown in FIG. 4 a , hereinabove, in accordance with an exemplary embodiment of the present invention, wherein the frequency ratio between the domains is less than 2; and
FIG. 5 is a signal relationship wave diagram of the conformational timer shown in FIGS. 4 a and 4 b , in accordance with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, block diagram 100 depicts an exemplary embodiment of a circuit for conformational representation of signal 112 . Signal 112 originates in a slow-clock domain 110 , which includes Slow Signal Splitter 120 (hereinbelow “SSS”) for the processing of signal 112 , whose processed output is transmitted into HF domain 150 . HF domain 150 includes conformational timer 160 (hereinbelow “SYN”). Components of slow-clock domain 110 are clocked by LF cycles from LF clock (not shown), applied by lead 111 . Components of slow-clock domain 150 are clocked by HF cycles of HF clock (not shown) applied by lead 151 . Incoming signal 112 , to be conformationally timed, is applied to a SSS 120 . SSS 120 comprises a double-input modulo- 2 adder XOR gate 122 , an feedback flip-flop 124 , an inverter 126 , and two double-input AND gates 128 and 130 .
Incoming signal 112 , having a duration of several LF line 111 clock cycles, is an input into AND gates 128 and 130 and into XOR gate 122 . XOR gate 122 output is applied to the D input terminal of feedback flip-flop 124 . The flip-flops of this embodiment are assumed to be of rising edge logic, although other logic could also be used. The first output of port Q of feedback flip-flop 124 is delayed by one LF clock period relative to signal 112 , and is:
applied as a second input into AND gate 128 ;
applied as a second input into AND gate 130 after its inversion by inverter 126 ; and is
fed back to constitute the second input into XOR gate 122 . As long as signal 112 is “1” (logical high), one of the outputs of gates 128 and 130 must be “1” (logical high) and the other must be “0” (logical low), generating complementary outputs of logical high and of logical low, respectively. The output of gate 128 , applied to lead 132 , is named inc_odd_slow, and the output of gate 130 , applied to lead 134 , is named inc_even_slow. These outputs alternate at one half of the LF clock frequency as long as signal 112 is logical high.
Referring now to fast clock domain 150 which includes:
HF clock output lead 151 , and
conformational timer 160 .
Conformational timer 160 comprises of:
Odd branch 161 , its input lead 132 and its output lead 168 ,
Even branch 181 , its input lead 134 and its output lead 188 ,
XOR gate 170 , its input leads 168 and 188 , and its output lead 192 .
XOR gate 170 output, applied to lead 192 , is the conformationally timed signal that constitutes this inventive circuit output.
Referring now to the operation of odd branch 161 , lead 132 output inc_odd_slow is applied to the D terminal of flip-flop 152 , whose Q terminal output is applied to the D terminal of flip-flop 154 . Two serially connected flip-flops 152 and 154 are needed due to signal stability reasons, as is known. The Q terminal output of flipflop 154 is applied both to the D terminal of flip-flop 156 and to one input terminal of a two terminal AND gate 166 . The Q terminal output of flip-flop 156 is inverted by inverter 160 , and the output of inverter 160 is applied to the other input terminal of gate 166 via lead 162 . The output of terminal Q of flip-flop 154 is delayed by two rising edges of HF clock signals behind output 132 , and the output of terminal Q of flip-flop 156 is delayed by three rising edges of HF clock signals behind output 132 , i.e. one HF rising edge behind flip-flop 154 . The output of AND gate 166 is high only when the output of flip-flop 154 is high and the output of gate 156 is low, i.e. if the output cycle at the two rising edges of HF period delay is high while the output cycle at the three rising edges of delay is low. This occurs when the output of line 132 changed from low to high between these two rising edges.
The operation of even branch 181 is similar to the operation of odd branch 161 . Lead 134 output inc_even_slow is applied to the D terminal of flip-flop 172 , whose Q terminal output is applied to the D terminal of flip-flop 174 . Two serially connected flip-flops 172 and 174 are needed due to signal stability reasons, as is known. The Q terminal output of flip-flop 174 is applied to the D terminal of flip-flop 176 and to one input terminal of a two terminal AND gate 186 . The Q terminal output of flip-flop 176 is inverted by inverter 180 and the output of inverter 180 is applied via lead 182 to the other input terminal of gate 186 . The output of terminal Q of flip-flop 184 is delayed by two rising edges of HF clock signals behind the output of 134 and the output of terminal Q of flip-flop 176 is delayed by three rising edges of HF clock signals behind the output of 134 , i.e. one HF period behind flip-flop 174 . Only if the output of flip-flop 174 is high while the output of gate 176 is low, the output of AND gate 186 is high, i.e. the output cycle at the two HF period delay is high while the output cycle at the three cycle delay is low. This occurs when the output of line 134 changed from low to high between these two cycles.
Referring now to FIG. 2 of the timing diagrams of various electrical signals shown in FIG. 1, line 1 shows the logical levels of the LF clock cycles, of 77.76 Mhz in this embodiment, and line 2 shows the logical levels of the HF clock cycles, of 100 Mhz in this embodiment. Full vertical lines mark the start of each LF cycle, while dotted vertical lines mark the start of each HF cycle. Line 3 shows the logical levels of the inc_odd_slow signal, lead 132 , represented by cycles of one half of the LF frequency and line 7 shows the logical levels of inc__even_slow signal, lead 134 . Line 4 shows the output of odd_clkd 1 of Q terminal of flip-flop 152 into lead 153 , rising to logical high after a logical high of 134 and after rising HF clock signal. Line 5 shows the output of odd_clkd 2 of Q terminal of flip-flop 154 to lead 155 , delayed by one HF clock signal relative to odd_clkd 1 , and line 6 depicts the odd branch output odd_cycle into lead 168 .
Similarly, Line 7 shows the logical levels of the inc_even_slow signal, lead 134 , represented by cycles of one half of the LF frequency and line 8 shows the logical levels of inc_even_slow signal. Line 8 shows the output of even_clkd 1 of flip-flop 172 Q terminal into lead 173 , rising to logical high after a logical high of 134 and after rising HF clock signal. Line 9 shows the output of even_clkd 2 of flip-flop 174 Q terminal into lead 175 , delayed by one HF clock signal relative to even_clkd 1 , and line 10 depicts the even branch output even_cycle, lead 188 . Line 11 depicts the inc_fast output of conformational timer 160 into lead 192 of this inventive apparatus 100 .
Referring now to FIG. 3, depicting a block diagram 200 of an exemplary embodiment circuit for the conformational representation of signal 212 originating in a HF domain 202 and transmitted into a LF domain 209 .
The detailed embodiment of the circuit depends on the integer numbers N and m, defined by the relationships:
N=INT ( HF/LF )+1 (1)
m >log 2 ( N ) (2)
Where N designates the number of the parallel output leads of Fast Signal Splitter 204 (FSS hereinbelow) for the splitting of signal 212 and the number m designates the number of output lines in bus 208 , m is preferably the smallest number satisfying relationship (2), or:
m=INT (log 2 ( N ))+1 (2a)
Bus 208 of m leads permits the log(2) representation in the LF domain of the number of HF cycles generated during one LF cycle duration. HF domain 202 also comprises of an output lead 211 of an HF clock (not shown). Also comprised in 202 is an N-outputs FSS 204 for the splitting of signal 212 into N outputs 221 , 231 , 241 , 251 , 261 , N equals five in this exemplary embodiment. Each one of said N outputs is applied to a corresponding module of N similar HF modules, designated respectively 220 through 260 . Each one of the outputs of said N HF modules is applied to a corresponding lead of N similar LF modules 320 through 360 , respectively. The N outputs of said LF modules are applied to LF counter 206 , generating in m-lined bus 208 a sequence of LF cycle-long binary representations of the number of HF cycle duration of signal 212 generated during each LF cycle.
Each one of the N HF modules 220 through 260 comprises a two-input XOR gate, numbered 222 through 262 in the respective modules, and an HF flip-flop, numbered 223 through 263 respectively, i.e. the HF flip-flop number equals the XOR gate number of its module increased by 1. The output of each group's XOR gate is applied to the D terminal of its respective HF flip-flop.
N LF modules, numbered 320 to 360 are provided and are connected to the Q outputs of HF flip-flops 223 to 263 by leads 225 through 265 , respectively. Each LF module comprises three serially connected LF flip-flops, first LF flip-flops numbered 321 to 361 , second LF flip-flops numbered 322 to 362 and third LF flip-flops numbered 323 to 363 , respectively. Also included are two-input LF modulo- 2 adders, which may be constituted by LF XOR gates numbered 324 to 364 , respectively. Lead 311 applies LF cycles to the clock terminal of any LF-clocked component.
The output of the Q terminal of each one of the respective HF flip-flops 223 through 263 is applied to the D terminal of the respective first LF flip-flops 321 to 361 , the outputs of the Q terminals of the first LF flip-flops are applied to the respective D terminals of the second LF flip-flops 322 to 362 and the outputs of the Q terminals of the second LF flip-flops are applied to respective D terminals of the third LF flip-flops 323 to 363 and to one input terminal of a respective two-input LF XOR gate 324 to 364 . The outputs of the Q terminals of the third LF flip-flops are applied to the respective second terminal of LF XOR gates 324 to 364 . The outputs of LF XOR gates 324 through 364 are applied in parallel through leads 325 through 365 , respectively, to N input terminals of adder 206 . Adder 206 outputs the number of input “1”'s, representing the duration of signal 212 , expressed in number of HF cycles, by the binary output of the L lines of bus 208 .
FSS 204 outputs a round robin sequence of outputs of one HF cycle-length duration in N lines 223 through 263 , said outputs being staggered by one HF cycle length and generated as long as line 212 is “1” or logical high. Each one of the logical high outputs of lines 223 through 263 is applied to the D input terminal of first flip-flops 321 through 361 , whose Q terminal outputs are applied to the D input terminals of second flip-flops 322 through 362 . First and second flip-flops are provided due to signal stability, as is known. The Q terminal output of second flip-flops 322 through 362 is applied to one input terminal of modulo- 2 adders 324 through 364 , respectively. The Q terminal outputs of third LF flip-flops 323 to 363 is applied to the second input terminal of the respective LF XOR gates 324 to 364 . The output of the LF XOR gates is logical high if the exectly one output of the second and the third LF flip-flops is logical high, i.e. if a change in the logical levels of said flip-flops occurred during the one LF cycle duration corresponding to the HF signal output of the respective HF line. The logical output levels in bus 208 of adder 206 represent the number of HF cycles, during which line 212 was logically high, during one LF cycle. This number could be less than N or equal to N. For a line 212 logical high signal duration of P HF cycles, P being less than N. the output representation on bus 208 is P during one LF cycle. For a line 212 logical high signal duration of R HF cycles, R being equal to N, the output representation on bus 208 is N during one LF cycle. For a line 212 logical high signal duration of S HF cycles, S being higher than N, the output representation on bus 208 is N during the integer number T=INT(S/N) of T LF cycles, and equals to (P modulo N) during the next LF cycle. Thus a representation of the HF cycle duration of signal 212 is transmitted to the LF domain and is represented there by the output of adder 206 , as represented on bus 208 .
Referring now to FIG. 4, a block diagram 400 is depicted of an exemplary embodiment of a circuit for the conformational representation of signal 412 originating in a HE domain 402 and transmitted into a LF domain 409 .
The detailed embodiment of the circuit depends on the integer numbers N and m, defined as above by the relationships (1) applied to the values used in the embodiment of FIG. 4 :
N=INT (100/77.76)+1=2 (1)
m >log 2 (2) (2)
Where N designates the number of the parallel output leads of FSS 404 for the splitting of signal 412 , and the number m designates the number of output lines in bus 408 m is preferably the smallest number satisfying relationship (2), or:
m=INT (log 2 (2))+1=2 (2a)
Bus 408 of two leads or bits permits the log(2) representation in the 77.76 MHz LF domain of the number of 100 MHz HF cycles generated during one LF cycle duration. HF domain 402 also comprises of an HF lead 411 of an HF clock (not shown), applied to the clock terminals of HF components.
Also comprised in 402 is an N-outputs FSS 404 , N equals 2 in this exemplary embodiment, for the splitting of signal 412 into N outputs 421 , 431 . Each one of outputs 421 , 431 , is applied respectively to one of two similar HF modules 420 , 430 . Each one of the outputs of said HF modules is applied to a corresponding lead of two LF modules 520 , 530 , respectively. The two outputs of said LF modules are applied to LF adder 406 , generating in a 2-lined bus 408 a sequence of LF cycle-long binary representations of the number of HF cycle duration of signal 412 generated during each LF cycle.
Each one of HF modules com 420 , 430 , comprises a two-input XOR gate, numbered 422 , 432 , and an HF flip-flop, numbered 223 , 233 respectively, i.e. the HF flip-flop number equals the XOR gate number of its module increased by 1. The output of each group's XOR gate is applied to the D terminal of its respective HF flip-flop.
Two LF modules, numbered 520 and 530 are provided, and are connected to the Q outputs of HF flip-flops 423 , 433 via leads 424 , 434 , respectively. Each LF module comprises three serially connected LF flip-flops, first LF flip-flops numbered 521 , 531 , second LF flip-flops numbered 522 to 532 and third LF flip-flops numbered 523 , 533 , respectively. Also included are two-input LF modulo- 2 adders, which may be constituted by LF XOR gates numbered 524 , 534 , respectively. Lead 511 applies LF clock cycles to the clock terminals of LF components.
The output of the Q terminal of each one of the respective synchronizer HF flip-flops is applied to the D terminal of the respective first LF flip-flops 521 , 531 , the outputs of the Q terminals of the first LF flip-flops are applied to the respective D terminals of second LF flip-flops 522 , 532 and the outputs of the Q terminals of the second LF flip-flops are applied to respective D terminals of the third LF flip-flops 523 , 533 and to one input terminal of a respective two-input LF XOR gate 524 , 534 , The outputs of the Q terminals of the third LF flip-flops are applied to the respective second terminal of LF XOR gates 524 , 534 , the outputs 525 , 535 of said LF XOR gates are applied in parallel to N input terminals of adder 406 . Adder 406 outputs the number of input “1”, representing the duration of signal 412 , expressed in number of HF cycles, by the binary output of the m lines of bus 408 .
FSS 404 outputs a round robin sequence of outputs of one HF cyclelength duration in N=2 lines 421 , 431 , said outputs being staggered by one HF cycle length and are generated as long as line 412 is “1” or logical high. The logical high outputs of flip-flops 423 , 463 , tg_ 1 , tg_ 2 are applied via leads 424 , 434 , respectively to the D input terminal of first flip-flops 521 , 531 , whose Q terminal outputs are applied to the D input terminals of second flip-flops 522 , 532 . First and second flip-flops are provided due to signal stability, as is known. The Q terminal output of second flip-flops 522 is applied to one input terminal of the two-input terminals of modulo- 2 adders, which may be constituted by XOR gates, and which are represented in this embodiment by LF XOR gates 524 , 534 . The Q terminal outputs of third flip-flops 523 , 533 is applied to the second input terminal of the respective LF XOR gates 524 , 534 . The outputs of the LF XOR gates are logical high if only one output of the second and the third LF flip-flops is logical high, namely, if a change in the logical levels of said flip-flops occurred during the particular LF cycle duration corresponding to the HF signal output of the respective HF line. Line 408 represents the number of HF cycles during which line 412 was logically high throughout one LF cycle. This number could be less than N or equal to N. For a line 412 logical high signal duration of P HF cycles, P being less than N, the output representation on bus 408 is P during one LF cycle. For a line 412 logical high signal duration of R HF cycles, R being equal to N, the output representation on bus 408 is N during one LF cycle. For a line 412 logical high signal duration of S HF cycles, S being higher than N, the output representation on bus 408 is N during the integer number T=INT(S/N) of T LF cycles, and equals to (P modulo N) during the next LF cycle. Thus a representation of the HF cycle duration of signal 412 , is transmitted to the LF domain and is represented there by the output of adder 406 , as represented on bus 408 .
Referring now to FIG. 5 of timing diagrams of various electrical signals of another embodiment wherein N=2, line 1 shows the logical levels of the HF clock cycles, of 100.0 Mhz in this embodiment, and line 7 shows the logical levels of the LF clock cycles, of 77.76 Mhz in this embodiment. Full vertical lines mark the end of each LF cycle, while dotted vertical lines mark the end of each HF cycle. Line 2 shows the logical levels of signal 412 . Lines 3 and 4 show the logical levels of the inc_ 1 and inc_ 2 of leads 421 and 431 outputs respectively. Lines 5 , 6 show the logical levels of tg_ 1 and tg_ 2 of leads 423 , 433 . Lines 8 and 10 show the output of tg_ 1 clkd 1 of Q terminal of flip-flop 521 , and of tg 1 clkd 2 of Q terminal of flip-flop 522 . Lines 9 and 11 show the output of tg_ 2 clkd 1 , tg_ 2 clkd 2 of the Q terminals of flip-flops 531 , 532 . Lines 12 and 13 show the outputs of XOR gates 524 , 534 , respectively, and line 14 shows the outputs of a two lines bus 408 .
Circuits constructed in accordance with the present invention may be particularly useful in communications applications, for example where signal transfer between different protocols may occur. Additionally, many processors may be comprised of several time domains and the present invention may enhance the efficiency of such processors and systems which use such processors, such as computer, networks, routers, servers, communications cards, and the like.
The preceding description of an exemplary embodiment is presented in order to enable a person of ordinary skill in the art to design, manufacture and utilize this invention. Various modifications and adaptations to the exemplary embodiment will be apparent to those skilled in the art, and different modifications may be applied to different embodiments. Therefore, it will be appreciated that the invention is not limited to what has been described hereinbelow merely by way of example. Rather, the invention is limited solely by the claims which follow this description. | Circuitry and methodology for transferring a representation of a data signal between clock domains. In particular, the disclosure teaches a method for creating representations of signals input from a slow clock domain into a fast clock domain and vice versa. The methods and apparatus use a RAM-free architecture which may be easily incorporated into integrated circuits to enhance efficiency. | 7 |
[0001] “This application claims priority from copending provisional application, application No. 60/434,004 filed Dec. 17, 2002 the entire disclosure of which is hereby incorporated by reference”
FIELD OF THE INVENTION
[0002] The invention relates to new antibiotics designated Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E, to production by fermentation, to methods for recovery and concentration from the crude solutions, to process for purification of Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D and Cyan-416 E and to the synthesis of the esters of Cyan-416 B.
BACKGROUND OF THE INVENTION
[0003] New improved antibiotics are continually in demand, for the treatment of diseases in man. Antibiotic resistant organisms are continually a problem, with Vancomycin the last defense, particularly in hospitals. Especially in hospitals, isolates, which are vancomycin resistant, are becoming more common. A recent survey found 7.9% of Enterococci in United States hospitals are now vancomycin resistant. “Nosocomial Enterococci Resistant to Vancomycin” Morbidity and Mortality Weekly Report 42(30):597-598(1993). Further resistance of Vancomycin and other antibiotics to Enterococcus faecium is reported, Handwergers. et al., Clin. Infect. Dis. 1993(16),750-755. Resistance organisms are also a problem for other important antibiotics, which includes methicillin.
[0004] Clearly, antibiotic resistance is a growing public health problem and having new antibiotics available could provide additional options for physicians in treatment regimens.
[0005] The medical community recognizes that there is an ongoing need for additional antibiotics. The search for new antibiotics which exhibit antibacterial activity against vancomycin-resistant isolates and having structures which are not derivatives of vancomycin are particularly appealing.
[0006] Antibiotics described in the literature include: Xanthoquinodins, Tabata, Noriko; Suzumura, Yasuko; Tomoda, Hiroshi; Masuma, Rokuro; Haneda, Katsuji; Kishi, Masanori; Iwai, Yuzuru; Omura, Satoshi. Xanthoquinodins, new anticoccidial agents produced by Humicola sp.: production, isolation, and physico-chemical and biological properties. J. Antibiot (1993),46(5),749-55. Tabata, Noriko; Tomoda, Hiroshi; Matsuzaki, Keiichi; Omura, Satoshi. Structure and biosynthesis of xanthoquinodins, anticoccidial antibiotics. J. Am. Chem. Soc . (1993), 115(19), 8558-64. Omura, Satoshi; Koda, Hiroshi; Masuma, Rokuro; Haneda, Katsuji; Iwai, Yuzuru. Anticoccidial agents manufactured with Humicola. (1994), 25 pp., JP 06116281 A2 19940426. Tabata, Noriko; Tomoda, Hiroshi; Iwai, Yuzuru; Omura, Satoshi. Xanthoquinodin B3, a new anticoccidial agent produced by Humicola sp. FO-888 . J. Antibiot . (1996), 49(3), 267-71 and Pinselic acid, related to Cyan-416 D is reported by Law, Kai-Kwong; Chan, Tze-Lock; Tam, Shang Wai; Shatin, N. T. Synthesis of pinselic acid and pinselin. J. Org. Chem . (1979), 44(24), 4452-3.
[0007] However, all of the above-disclosed antibiotics are distinct from the present invention.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention relates to the following antibiotic compounds: Antibiotic Cyan-416 A having the structure:
[0009] Antibiotic Cyan-416 B having the structure:
[0010] Antibiotic Cyan-416 C having the structure:
[0011] Antibiotic Cyan-416 D having the structure:
[0012] Antibiotic Cyan-416 E having the structure:
[0013] and
[0014] further relates to esters of Cyan-416 B of Formula I and a process for the preparation thereof
[0015] where R is straight or branched alkyl of 1 to 10 carbon atoms, alkenyl of 2 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms and cycloalkenyl of 3 to 10 carbon atoms.
[0016] The present invention includes within its scope the agents in dilute form, as a crude concentrate, and in pure form. The present invention also relates to the use of the compounds according to the invention in antimicrobial compositions and as an antiseptic, or disinfectant.
[0017] It is an object of this invention to provide compounds of the invention, which are shown to possess antibacterial activity, especially against vancomycin resistant bacterial isolates and in particular having a chemical structure unlike vancomycin.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] [0018]FIG. 1. shows ultraviolet absorption spectrum of Cyan-416 A.
[0019] [0019]FIG. 2. shows ultraviolet absorption spectrum of Cyan-416 B.
[0020] [0020]FIG. 3. shows ultraviolet absorption spectrum of Cyan-416 C.
[0021] [0021]FIG. 4. shows ultraviolet absorption spectrum of Cyan-416 D.
[0022] [0022]FIG. 5. shows ultraviolet absorption spectrum of Cyan-416 E.
[0023] [0023]FIG. 6. shows proton nuclear magnetic resonance spectrum of Cyan-416 A in DMSO-d 6 at 400 MHz.
[0024] [0024]FIG. 7. shows proton nuclear magnetic resonance spectrum of Cyan-416 B in DMSO-d 6 at 400 MHz.
[0025] [0025]FIG. 8. shows proton nuclear magnetic resonance spectrum of Cyan-416 C in DMSO-d 6 at 400 MHz.
[0026] [0026]FIG. 9. shows proton nuclear magnetic resonance spectrum of Cyan-416 D in DMSO-d 6 at 400 MHz.
[0027] [0027]FIG. 10. shows proton nuclear magnetic resonance spectrum of Cyan-416 E in DMSO-d 6 at 400 MHz.
[0028] [0028]FIG. 11. shows carbon-13 nuclear magnetic resonance spectrum of Cyan-416 A in DMSO-d 6 at 100 MHz.
[0029] [0029]FIG. 12. shows carbon-13 nuclear magnetic resonance spectrum of Cyan-416 B in DMSO-d 6 at 100 MHz.
[0030] [0030]FIG. 13. shows carbon-13 nuclear magnetic resonance spectrum of Cyan-416 C in DMSO-d 6 at 100 MHz.
[0031] [0031]FIG. 14. shows carbon-13 nuclear magnetic resonance spectrum of Cyan-416 D in DMSO-d 6 at 100 MHz.
[0032] [0032]FIG. 15. shows carbon-13 nuclear magnetic resonance spectrum of Cyan-416 E in DMSO-d 6 at 100 MHz.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] The invention relates to new antibiotics Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D and Cyan-416 E, to the production of the antibiotics by fermentation, to methods for the recovery and concentration of the antibiotics from crude solutions, and to processes for the purification of the antibiotics. The invention includes within its scope the new antibiotics in diluted form, as crude concentrate and in pure form. The novel antibiotics are useful as antibacterial agents.
[0034] As used herein the term alkyl means a branched or straight chain radical having from 1 to 10 carbon atoms.
[0035] As used herein the term alkenyl as used herein means an unsaturated branched or straight chain radical having from 2 to 10 carbon atoms. Alkenyl, may be used synonymously with the term olefin and includes alkylidenes. Exemplary alkenyl groups include but are not limited to ethylene, propylene and isobutylene.
[0036] As used herein the term cycloalkyl means a saturated monocyclic ring having from 3 to 10 carbon atoms. Exemplary cycloalkyl rings include but are not limited to cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl,
[0037] As used herein the term cycloalkenyl means a non-aromatic monocyclic ring system containing a carbon-carbon double bond and having about 3 to about 10 atoms. Preferred monocyclic cycloalkenyl rings include cyclopentenyl and cyclohexenyl.
[0038] The new antibiotics designated Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D and Cyan-416 E are formed during the fermentation of Acremonium sp. NRRL 30631.
[0039] The structure of the new antibiotic Cyan-416 A is:
[0040] The physico-chemical characteristics of Cyan-416 A are as follows:
[0041] 1. Molecular weight: 614 (ESIMS);
[0042] 2. Apparent molecular formula: C 33 H 26 O 12 ;
[0043] 3. High-resolution Fourier transform ion cyclotron resonance mass spectrum (positive): m/z 615.14913 (MH + , C 33 H 27 O 12 requires 615.14970);
[0044] 4. Ultraviolet absorption spectrum as shown in FIG. 1;
[0045] 5. Proton nuclear magnetic resonance signals as shown in FIG. 6 (400 MHz, DMSO-d 6 );
[0046] 6. Carbon-13 nuclear magnetic resonance signals as shown in FIG. 11 (100 MHz, DMSO-d 6 ), with significant signals listed below:
199.88 187.56 183.39 169.69 167.70 160.45 159.55 158.48 151.00 147.22 145.61 145.50 136.70 132.37 131.68 131.09 123.18 122.04 118.88 117.66 113.08 112.44 112.06 109.48 108.69 105.45 72.46 52.01 41.08 37.62 33.93 21.52 20.78
[0047] The structure of the new antibiotic Cyan-416 B is:
[0048] The physico-chemical characteristics of Cyan-416 B are as follows:
[0049] 1. Molecular weight: 572 (ESIMS);
[0050] 2. Apparent molecular formula: C 31 H 24 O 11 ;
[0051] 3. High-resolution Fourier transform ion cyclotron resonance mass spectrum (positive): m/z 573.13900 (MH + , C 31 , H 25 O 11 requires 573.13968);
[0052] 4. Ultraviolet absorption spectrum as shown in FIG. 2;
[0053] 5. Proton nuclear magnetic resonance signals as shown in FIG. 7 (400 MHz, DMSO-d 6 );
[0054] 6. Carbon- 13 nuclear magnetic resonance signals as shown in FIG. 12 (100 MHz, DMSO-d 6 ), with significant signals listed below:
199.86 187.03 184.84 167.76 160.51 159.50 158.39 151.04 147.07 146.31 145.53 142.73 134.69 131.16 130.18 122.22 122.08 117.64 117.36 113.77 112.45 111.63 109.45 108.64 106.16 71.39 52.02 42.37 37.41 34.44 21.56
[0055] The structure of the new antibiotic Cyan-416 C is:
[0056] The physico-chemical characteristics of Cyan-416 C are as follows:
[0057] 1. Molecular weight: 630 (ESIMS);
[0058] 2. Apparent molecular formula: C 33 H 26 O 13 ;
[0059] 3. High-resolution Fourier transform ion cyclotron resonance mass spectrum (positive): m/z 631.14490(MH + , C 33 H 27 O 13 requires 631.14462);
[0060] 4. Ultraviolet absorption spectrum as shown in FIG. 3;
[0061] 5. Proton nuclear magnetic resonance signals as shown in FIG. 8 (400 MHz, DMSO-d 6 );
[0062] 6. Carbon-13 nuclear magnetic resonance signals as shown in FIG. 13 (100 MHz, DMSO-d 6 ), with significant signals listed below:
202.78 199.83 195.54 171.03 167.72 162.68 158.96 158.55 151.09 149.44 145.55 145.00 139.53 134.60 131.00 128.72 122.14 118.24 117.69 117.38 114.67 112.33 109.90 108.85 108.60 81.51 70.12 51.95 46.74 43.40 31.51 21.84 20.86
[0063] The structure of the new antibiotic Cyan-416 D is:
[0064] The physico-chemical characteristics of Cyan-416 D are as follows:
[0065] 1. Molecular weight: 318 (ESIMS);
[0066] 2. Apparent molecular formula: C 16 H 14 O 7 ;
[0067] 3. High-resolution Fourier transform ion cyclotron resonance mass spectrum (positive): m/z 319.08104 (MH + , C 16 H 15 O 7 requires 319.08177);
[0068] 4. Ultraviolet absorption spectrum as shown in FIG. 4;
[0069] 5. Proton nuclear magnetic resonance signals as shown in FIG. 9 (400 MHz, DMSO-d 6 );
[0070] 6. Carbon-13 nuclear magnetic resonance signals as shown in FIG. 14 (100 MHz, DMSO-d 6 ), with significant signals listed below:
199.35 168.06 161.57 151.23 147.56 145.65 131.24 122.21 117.52 112.36 108.96 107.53 51.94 21.65
[0071] The structure of the new antibiotic Cyan-416 E is:
[0072] The physico-chemical characteristics of Cyan-416 E are as follows:
[0073] 1. Molecular weight: 648 (ESIMS);
[0074] 2. Apparent molecular formula: C 33 H 28 O 14 ;
[0075] 3. High-resolution Fourier transform ion cyclotron resonance mass spectrum (negative): m/z 647.14154 (M-H, C 33 H 27 O 14 requires 647.14016);
[0076] 4. Ultraviolet absorption spectrum as shown in FIG. 5;
[0077] 5. Proton nuclear magnetic resonance signals as shown in FIG. 10 (400 MHz, DMSO-d 6 );
[0078] 6. Carbon-13 nuclear magnetic resonance signals as shown in FIG. 15 (100 MHz, DMSO-d 6 ), with significant signals listed below:
199.56 168.06 160.99 157.67 151.28 146.97 145.48 131.44 122.23 117.24 116.67 111.98 108.50 108.08 51.76 21.44 20.16
[0079] A further preferred embodiment within the scope of this invention relates to the novel esters of Cyan-416 B and the process for the production of these compounds (Formula I):
[0080] where R is straight or branched alkyl of 1 to 10 carbon atoms, alkenyl of 2 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms and cycloalkenyl of 3 to 10 carbon atoms.
[0081] Preferably R is —CH 2 CH 2 CH 3 , —CH(CH 3 ) 2 , —CH 2 CH 2 CH 2 CH 3 , or —CH 2 CH 2 CH 3 .
[0082] The new antibacterial agents Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D and Cyan-416 E are formed during the cultivation under controlled conditions of a fungus, LL-Cyan-416, which is a strain of Acremonium sp. NRRL 30631.
[0083] This microorganism is maintained in the cultural collection of Wyeth Research, Pearl River, New York 10965, as culture LL-Cyan-416.
[0084] Description of LL-Cyan-416
[0085] Culture LL-Cyan-426 is that of a fungus, Acremonium sp., isolated from a sample collected from a mixed Douglas Fir-Hardwood forest, Crane Island Preserve, San Juan County, Washington State, in 1993. The culture has been deposited with Agricultural Research Services Culture Collection (NRRL), National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture at 1815 North University Street, Peoria, Ill. 61604 as NNRL 30631.
[0086] The culture LL-Cyan-416, identified as Acremonium sp., exhibits the following morphological features:
[0087] On oatmeal agar (Difco Laboratories), colony attaining a diameter of 37 mm after 21 days at 25° C. Colony mat white to Yellowish White (4A2), floccose; reverse Ivory (4B3); very light brown pigment present and exudate absent.
[0088] On potato-dextrose agar (Difco) colony attaining a diameter of 39.5 mm after 21 days at 25° C. Colony mat white, sulcate; reverse Pompeian Yellow (5C6) to Golden Brown (5D7), to margin Champagne (4B4); pigment and exudate absent.
[0089] On corn meal agar (Difco) colony attaining a diameter of 24.7 mm after 21 days at 25° C. Colony mat Yellowish White (3A2), floccose; reverse Yellowish White (3A2); pigment and exudate absent.
[0090] On YpSs agar (0.4% yeast extract, 1% soluble starch, 1.5% agar (all Difco), 0.05% K 2 HPO 4 (Sigma), pH 7.2) colony attaining 39 mm after 21 days at 25° C. Colony mat white, sulcate; reverse Light Yellow (4A4) to margin Yellowish White (3A2) to Pale Yellow (3A3); pigment and exudate absent.
[0091] The characteristics of colony described were based on Methuen Handbook of colour (Kornerup, A. and Wanscher, J. H. 3 rd ed., 252 p., Eyre Methuen, London. 1978.
[0092] Mycelium micronematous; conidophores simple to sometimes branched, phialides usually arising from aerial hyphae, erect, collarette not visible, 15.5-30 um height, widest portion 1.5 um and gradually taper to 0.5 um; conidia in slim heads, asymmetrical, elongate ellipsoidal to fusoid, 3-6×1.5 um, hyaline, smooth walled; chlamydospores absent.
[0093] For the production of the new antibiotics, of the present invention are not limited to this particular organism or to organisms fully answering the above characteristics, which are given for illustration purpose only. It is desired and intended to include the use of mutants produced from this organism by various means such as exposures to X-radiation, ultraviolet radiation, N′methyl-N′-nitro-N-nitrosoguanidine, phages, and like.
ACYLATION METHOD FOR THE PREPARATION OF COMPOUNDS OF FORMULA I
[0094] The selective acylation of Cyan-416 B 1 with an anhydride of the formula (R—C(O)—) 2 O where R is straight and branched alkyl of 1 to 10 carbon atoms, alkenyl of 2 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms and cycloalkenyl of 3 to 10 carbon atoms in the presence of boron trifluoride diethyl etherate (BF 3 -Et 2 O) affords an ester derivative of Cyan-416 B 2 as shown in Scheme 1.
[0095] where R is straight or branched alkyl of 1 to 10 carbon atoms, alkenyl of 2 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms and cycloalkenyl of 3 to 10 carbon atoms.
[0096] Preferably, R is —CH 2 CH 2 CH 3 , —CH(CH 3 ) 2 , —CH 2 CH 2 CH 2 CH 3 , or —CH 2 CH 2 CH 3 . As further shown in Scheme 2, hydrolysis with acid of Cyan-416 A 3 affords Cyan-416 B 1.
Biological Activity
[0097] Standard Pharmacological Test Procedures
[0098] The minimum inhibitory concentration (MIC), the lowest concentration of the antibiotic which inhibits growth of the test organism, is determined by the broth dilution method using Muller-Hinton II agar (Baltimore Biological Laboratories) following the recommendations of the National Committee for Clinical Laboratory Standards [Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Approved standard M7-A2. National Committee for Clinical Laboratory Standards, Villanova, Pa].
[0099] An inoculum level of 5×10 5 CFU/ml, and a range of antibiotic concentrations (64-0.06 μ/ml) is used. The MIC is determined after the microtiter plates are incubated for 18 hours at 35° C. in an ambient air incubator. The test organisms comprise a spectrum of the Gram-positive bacteria Staphylococcus aureus, Streptococcus pneumoniae , and Enterococcus sp ., the Gram-negative bacteria Escherichia coli , and the yeast Candida albicans . These organisms include recent clinical isolates that are resistant to methicillin and vancomycin. MIC data of Cyan-416 A-E are listed in Table 1 and MIC data of ester derivatives of Cyan-416 B (Formula I) are listed in Table 2.
TABLE 1 Antimicrobial Activity of Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E. MIC (μg/ml) Cyan 416 A Cyan 416 B Cyan 416 C Cyan 416 D Cyan 416 E Test organism Example 3a Example 3b Example 3c Example 4a Example 4b Staphylococcus aureus GC 4536 8 32 32 64 64 Staphylococcus aureus GC 1131 8 32 32 64 64 Staphylococcus aureus GC 2216 8 32 32 64 64 Enterococcus faecalis GC 842 16 64 32 64 64 Enterococcus faecalis GC 2242 16 32 32 32 64 Enterococcus faecalis GC 4555 16 64 64 64 64 Pseudomonas aeruginosa GC 2214 >64 >64 >64 >64 64 Escherichia coli GC 2203 >64 >64 >64 >64 >64 Escherichia coli GC 4560 (imp) 32 64 >64 64 64 Candida albicans GC 3066 >64 >64 >64 >64 64
[0100] [0100] TABLE 2 Antimicrobial Activity of Esters of Cyan-416 B (Formula I). MIC (μg/ml) Formula I, R = CH 3 (Cyan416-A) (CH 2 ) 2 CH 3 CH(CH 3 ) 2 (CH 2 ) 3 CH 3 (CH 2 ) 4 CH 3 Test organism Example 3a Example 6 Example 7 Example 8 Example 9 Staphylococcus aureus GC 1131 8 8 4 4 4 Staphylococcus aureus GC 4541 16 8 2 4 4 Staphylococcus aureus GC 4543 8 8 4 4 4 Staphylococcus aureus GC 2216 8 8 4 4 4 Staphylococcus haemolyticus GC 4547 16 16 4 4 4 Enterococcus faecalis GC 6189 16 16 4 4 4 Enterococcus faecalis GC 4555 16 16 4 4 4 Enterococcus faecalis GC 2242 16 8 4 4 4 Enterococcus faecium GC 4556 16 8 4 4 4 Enterococcus faecium GC 2243 8 16 8 4 4 Enterococcus faecium 4558 8 8 2 2 2 Streptococcus pneumoniae GC 1894 8 16 8 8 8 Streptococcus pneumoniae GC 6242 8 32 16 8 8 Escherichia coli coli GC 2203 >128 >128 >128 >128 >128 Escherichia coli GC 4560 (imp) 32 16 8 8 8 Candida albicans GC 3066 >128 >128 >128 >128 >128
[0101] The in vitro antimicrobial results show that the products according to the invention have significant activity against Gram-positive bacteria tested.
[0102] Antibiotic Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B derive their utility from antibacterial activity. For example, Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E may be used in the suppression of bacterial infections, as topical antibacterial agents or as a general disinfectant. Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E and esters of Cyan-416 B are not limited to the uses listed. In therapeutic use, the compound of this invention may be administered in the form of conventional pharmaceutical compositions appropriate for the intended use. Such compositions may be formulated as to be suitable for oral, parenteral or topical administration. The active ingredient may be combined in admixture with a nontoxic pharmaceutical carrier that may take a variety of forms depending on the form of preparation desired for administration, i.e. oral, parenteral, or topical.
[0103] When the compounds of the invention are employed as antibacterials, they can be combined with one or more pharmaceutically acceptable carriers, for example, solvents, diluents and the like, and may be administered orally in such forms as tablets, capsules, dispersible powders, granules, or suspensions containing, for example, from about 0.05 to 5% of suspending agent, syrups containing, for example, from about 10 to 50% of sugar, and elixirs containing for example, from about 20 to 50% ethanol and the like, or parenterally in the form of sterile injectable solutions or suspensions containing from about 0.05 to 5% suspending agent in an isotonic medium. Such pharmaceutical preparations may contain, for example, from about 25 to about 90% of the active ingredient in combination with the carrier, more usually between about 5% and 60% by weight. An effective amount of compound from 0.01 mg/kg of body weight to 100.0 mg/kg of body weight should be administered one to five times per day via any typical route of administration including but not limited to oral, parenteral (including subcutaneous, intravenous, intramuscular, intrasternal injection or infusion techniques), topical or rectal, in dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles. It will be understood, however, that the specific dose level and frequency of dosage for any particular patient may be varied and will depend upon a variety of factors including the activity of the specific compound employed, the metabolic stability and length of action of that compound, the age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the particular condition of the host undergoing therapy.
[0104] Additionally, the antibacterially effective amount of the antibiotic of the invention may be administered at a dosage and frequency without inducing side effects commonly experienced with conventional antibiotic therapy which could include hypersensitivity, neuromuscular blockade, vertigo, photosensitivity, discoloration of teeth, hematologic changes, gastrointestinal disturbances, ototoxicity, and renal, hepatic, or cardiac impairment. Further the frequency and duration of dosage may be monitored to substantially limit harmful effects to normal tissues caused by administration at or above the antibacterially effective amount of the antibiotic of the invention.
[0105] The active compound of the invention may be administered orally as well as by intravenous, intramuscular, or subcutaneous routes. Solid carriers include starch, lactose, dicalcium phosphate, microcrystalline cellulose, sucrose and kaolin, while liquid carriers include sterile water, polyethylene glycols, non-ionic surfactants and edible oils such as corn, peanut and sesame oils, as are appropriate to the nature of the active ingredient and the particular form of administration desired. Adjuvants customarily employed in the preparation of pharmaceutical compositions may be advantageously included, such as flavoring agents, coloring agents, preserving agents, and antioxidants, for example, vitamin E, ascorbic acid, BHT and BHA. The active compound may also be administered parenterally or intraperitoneally. Solutions or suspensions of the active compound as a free base or pharmacologically acceptable salt can be prepared in glycerol, liquid, polyethylene glycols and mixtures thereof in oils. Under ordinary conditions of storage and use, these preparations contain a preservative. The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacterial and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (e.g., glycerol, propylene glycol and liquid polyethylene glycol), suitable mixtures thereof, and vegetable oil.
[0106] The invention accordingly provides a pharmaceutical composition, which comprises a compound of this invention in combination or association with a pharmaceutically acceptable carrier. In particular, the present invention provides a pharmaceutical composition, which comprises an antibacterially effective amount of a compound of this invention and a pharmaceutically acceptable carrier.
[0107] The present invention further provides a method of treating bacterial infections in warm-blooded animals including man, which comprises administering to the afflicted warm-blooded animals an antibacterially effective amount of a compound or a pharmaceutical composition of a compound of the invention. The invention will be more fully described in conjunction with the following specific examples, which are not to be construed as limiting the scope of the invention.
[0108] As used herein an effective amount refers to the quantity of a compound of the invention which is sufficient to yield a desired therapeutic response without undue adverse side effects (such as toxicity) commensurate with a reasonable benefit/risk ratio when used in the method of this invention.
[0109] The Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B according to the invention, have good antimicrobial activity may be used in antimicrobial compositions, especially as an antiseptic by local and general application, and as a disinfectant.
[0110] As antiseptics for human or veterinary use, the concentration of active product can vary from about 0.01% to 5% by weight according to the use and the chosen formulation. Thus, it is possible to prepare foaming detergent solutions to be used by surgeons and nursing staff for washing their hands or to be used for cleansing dermatological lesions such as impetigo, pityriasis and leg ulcers. Foaming detergent solutions are also used as shampoos (for example antidandruff shampoos) or for the preparation of shower gels, shaving creams and foaming lotions. Foaming solutions containing Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B according to the invention are obtained using amphoteric, anionic, cationic or non-ionic surfactants at a concentration of about 0.3 to 30%, humectants such as glycols or polyethylene glycols, at a concentration of 0 to 20% ethylene oxide and polypropylene copolymers at a concentration of 0 to 20%, and an alcohol (ethanol, isopropanol, benzyl alcohol) or a polyol, such as glycerol, at a concentration of 0 to 15%, as well as agents for complexing Ca++, Mg++and heavy metal ions, salts for providing an appropriate buffer capacity, agents for imparting viscosity, such as NaCl or KCl, natural, cellulosic or synthetic polymers such as polyvinylpyrrolidone, thickening superfatting agents such as polyethylene glycol distearate or copra monoethanolamide or diethanolamide, fragrances, preservatives and colorants.
[0111] It is possible to use microemulsions, micellar solutions or any other phase of the ternary or quaternary diagram of water/active principle/surfactant/co-surfactant which permits solubilization of Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B in water. These solutions can be used in diluted or undiluted form and can be dispensed for example by means of a vasopump or liquefied or non-liquefied propellants.
[0112] With the same constituents at appropriate concentrations, the product according to the invention can also be used to prepare simple aqueous solutions or aqueous solutions in the form of sprays for making operative fields antiseptic, for postoperative treatments, for the treatment of burns, superinfected eczema, gluteal erythema, wounds or acne, or for deodorants.
[0113] Simple alcoholic solutions or alcoholic solutions in the form of sprays containing 20 to 80% by weight of alcohol can contain, apart from the excipients used in aqueous solutions, excipients which make it possible to penetrate the keratinized layers of the skin and superficial body growths, such as Azone (marketed by Nelson Research) and Transcutol (marketed by Gattefosse). These solutions are to be used for making the skin antiseptic before puncture, for preparing the operative field, by nursing staff for making their hands antiseptic and for treating closed infected dermatosis, folliculitis, perionychia or acne. Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B according to the invention can be applied in the form of creams together with the fatty substances normally found in the preparation of creams or emulsions. Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and Cyan-416 B and esters of Cyan-416 B according to the invention can also be used in animals for indications such as the prevention or treatment of infected lesions. In this case, the pharmaceutical compositions are similar to those used in man, in particular creams sprays or solutions.
[0114] Moreover, the rapid lethal action on germs of Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B according to the invention may be used as surface disinfectants at concentrations which can vary from about 0.1 to 4% by weight. In this case, Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, Cyan-416 E and esters of Cyan-416 B is used in preparations such as aqueous or non-aqueous foaming detergent solutions, sprays or nebulizers. This type of preparation is particularly useful in the hospital or veterinary sectors. These preparations can contain the same constituents as those used in the antiseptic formulations, although a variety of organic solvents may be added.
[0115] General Fermentation Conditions
[0116] Culture LL-Cyan-416 Acremonium sp. NRRL30631 is inoculated on moist milk-filter paper placed on the surface of a solid, agar medium containing agar, malt extract, peptone, and yeast extract and incubated under stationary conditions at 22° C.
[0117] General Isolation Procedures of Antibiotics Cyan-416 A, B, C, D, and E
[0118] The Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E are recovered from the fermentation broth by extracting cells with methanol. The methanol extract is evaporated under reduced pressure and the concentrate purified by HPLC on C18 columns using acidic acetonitrile in water to afford Cyan-416 A, Cyan-416 B, Cyan-416 C, Cyan-416 D, and Cyan-416 E.
[0119] The invention is further described in conjunction with the following non-limited examples.
EXAMPLE 1
Inoculum Preparation
[0120] Fungal culture LL-Cyan-416 is plated on Bennett's agar medium (10 g/l Sigma D-glucose, 1 g/l Difco beef extract, 1 g/l Difco yeast extract, 2 g/l N-Z amine A, 20 g/l Difco agar) from a frozen 25% glycerol stock culture and then incubated at 22° C. A small agar slice bearing mycelial growth is used to inoculate 50 ml of Difco potato-dextrose broth in a 250-ml Erlenmeyer flask. This liquid seed culture is shaken at 200 rpm at 22° C. for one week, and then used to inoculate production medium.
EXAMPLE 2
Fermentation
[0121] Production medium (1 L) consisted of malt extract agar (25 g Difco malt extract, 5 g Difco peptone, 0.5 g Difco yeast extract, 20 g Difco agar) that has been sterilized and poured into a 30×20×13 cm polypropylene tray covered with aluminum foil. The solidified agar is then overlaid with a sterile 28×46 cm sheet of nongauze milk-filter paper cut from 18×22 in strips (KenAG Animal Care Group, Ashland, Ohio) that had been sterilized separately. The production medium is inoculated by pipeting 50 ml of seed culture fluid onto the sheet of milk-filter paper. The inoculated tray culture is incubated stationary at 22° C. After 2 weeks of incubation, the milk-filter paper bearing prolific mycelial growth is peeled from the surface of the agar, lyophilized for 5 days, and then extracted with methanol (1.2 L).
EXAMPLES 3 a , 3 b , and 3 c
Purification of New Antibiotics Cyan-416 A( 3 a ), Cyan-416 B( 3 b ), and Cyan-416 C( 3 c )
[0122] [0122]
[0123] The methanol extract obtained in EXAMPLE 2 is chromatographed by reverse phase HPLC on a C18 column (YMC ODS-A, 10 μm particle size, 70×500 mm), using a linear gradient of 30-100% acetonitrile in water containing 0.01% trifluoroacetic acid (TFA) over 35 min. Four fractions at 27.5, 30.5, 35.0, and 38.37 minutes are collected. The materials from the later three fractions at 30.5, 35.0, and 38.37 minutes are respectively purified by a different HPLC system (YMC ODS-A, 5 μm, 30×250 mm column, 40-75% acetonitrile in water containing 0.01% TFA over 30 min) to afford cyan-416 B (4.5 mg), cyan-416 C (4.2 mg), and cyan-416 A (130.8 mg), all as yellow amorphous powders.
EXAMPLES 4 a and 4 b
Purification of New Antibiotics Cyan-416 D( 4 a ) and Cyan-416 E( 4 b )
[0124] [0124]
[0125] The material from the first fraction at 27.5 minutes described in EXAMPLE 3 is further separated by HPLC (YMC ODS-A, 5 μm, 30×250 mm column, 30-100% acetonitrile in water containing 0.01% TFA over 30 min) to afford pure Cyan-416 D (21.0 mg) and cyan-416 E (3.1 mg), both as pale yellow amorphous powders.
EXAMPLE 5
Production of Cyan-416 B from Cyan-416 A
[0126] [0126]
[0127] A solution of Cyan-416 A (120.0 mg) in 1 ml 1:1 Et 2 O/MeOH containing 0.5 M hydrochloric acid is stirred at ambient temperature for 24 hours. The purification of the resulting mixture by HPLC (same system as in Example 4) affords Cyan-416 B (102.5 mg). ESIMS (negative) m/z 571 (M-H) − .
EXAMPLE 6
Cyan-416 B Butyrate
[0128] [0128]
[0129] To a solution of Cyan-416 B (20.0 mg) in dry tetrahydrofuran (0.5 ml), is added dropwise a solution of 7% (v/v) of BF 3 -Et 2 O in butyric anhydride (0.2 ml) at 0° C. The reaction mixture is stirred at this temperature for 2 hours before methanol (2.0 ml) is added. The resulting solution is stirred for 0.5 hour at ambient temperature and then chromatographed by HPLC on a C18 column (YMC ODS-A, 5 μm particle size, 30×250 mm) using a linear gradient (40-100% acetonitrile. in water containing 0.01% TFA in 30 minutes) to afford Cyan-416 B butyrate (15.3 mg, Formula I, R=CH 2 CH 2 CH 3 ). ESIMS (negative) m/z 641 (M-H) − .
EXAMPLE 7
Cyan-416 B Isobutyrate
[0130] [0130]
[0131] Cyan-416 B (20.0 mg) is acylated using isobutyric anhydride to replace butyric anhydride in the procedure described in EXAMPLE 6 to afford Cyan-416 B isobutyrate (12.0 mg, Formula I, R=CH(CH 3 ) 2 ). ESIMS (negative) m/z 641 (M-H) − .
EXAMPLE 8
Cyan-416 B Pentanoate
[0132] [0132]
[0133] Cyan-416 B (20.0 mg) is acylated using pentanoic anhydride to replace butyric anhydride in the procedure described in EXAMPLE 6 to afford Cyan-416 B pentanoate (17.2 mg, Formula I, R=CH 2 CH 2 CH 2 CH 3 ). ESIMS (negative) m/z 655 (M-H) − .
EXAMPLE 9
Cyan-416 B Hexanoate
[0134] [0134]
[0135] Cyan-416 B (20.0 mg) is acylated using hexanoic anhydride to replace butyric anhydride in the procedure described in EXAMPLE 6 to afford Cyan-416 B hexanoate (17.8 mg, Formula I, R=CH 2 CH 2 CH 2 CH 2 CH 3 ). ESIMS (negative) m/z 669 (M-H) − . | The invention relates to new antibiotics designated Cyan-416A, Cyan 416B, Cyan-416C, Cyan-416D and Cyan-416E to their production by fermentation of Acremonium sp. NRRL 30631 to methods for recovery and concentration from the crude solutions, and to a process for purification and to semisynthetic ethers of Cyan-416B. | 2 |
FIELD OF THE INVENTION
The present invention relates to an outside-of-thorax type negative pressure artificial respirator, and more particularly to an outside-of-thorax type negative pressure artificial respirator suited for restraining an abrupt variation in air pressure within a corset.
BACKGROUND OF THE INVENTION
Although there are many types of artificial respirators, the mainstream at present is an apparatus of the positive pressure type which applies positive pressure directly into the trachea. With this apparatus, although the artificial respiration can be positively effected, an incision of the trachea is needed, and the incision portion must be sterilized. A further disadvantage of the positive pressure type respirator is that the patient is unable to consume food or effectively speak. Another type of respirator is a negative pressure type apparatus commonly referred to as an "iron lung". The negative pressure type apparatus also has disadvantages in that it is bulky and is low in efficiency. As a result, the negative pressure type apparatus has been seldomly used in recent years. Another negative pressure type apparatus is one known as an outside-of-thorax type negative pressure artificial respirator. This apparatus includes a corset having a rigid shell for enclosing the thorax of the patient, and forms an air-tight chamber between the thorax and the rigid shell when the corset is attached. By bringing the sealed chamber into a negative pressure, the artificial respiration is carried out. Since this apparatus does not need an incision of the trachea, and can be easily used, the apparatus has recently been extensively used.
FIG. 7 shows a conventional outside-of-thorax type negative pressure artificial respirator including the corset 50 and a suction pump 51 which are interconnected by an inspiration tube 52, and a two-way directional control valve 53 is mounted in a conduit of the inspiration tube 52 so that the inspiration tube 52 can be selectively opened and closed relative to the atmosphere. During the inspiration period, the two-way directional control valve 53 is closed relative to the atmosphere to bring the pressure within the corset 50 to a negative pressure. During the expiration period, the valve 53 is opened relative to the atmosphere to return the pressure within the corset 50 to the atmospheric pressure. By controlling the pressure within corset 50 in this manner, artificial respiration is carried out.
However, in the conventional apparatus shown in FIG. 7 the directional control of the conduit by the two-way directional control valve 53 is instantaneously effected. Specifically, the pressure within corset 50 is abruptly changed between a negative pressure and the atmospheric pressure, as shown in FIG. 8. This results in a problem in that the patient is subjected to an impact which causes pain.
As described above, the conventional outside-of-thorax type negative pressure artificial respirator has a problem in that when the tube pipe connected to the corset is to be opened and closed relative to the atmosphere, the two-way directional control valve achieves the directional control of the conduit instantaneously, and therefore the pressure within the corset is abruptly changed to provide an impact and hence a pain to the patient.
SUMMARY OF THE INVENTION
The present invention has been developed in order to overcome the problems associated with the prior art negative pressure type artificial respirators. Specifically, an object of the invention is to provide an outside-of-thorax type negative pressure artificial respirator which gently varies the change in pressure within a corset during the artificial respiration, thereby preventing pain to the patient.
The above object has been achieved by an outside-of-thorax type negative pressure artificial respirator comprising a corset including a rigid shell for enclosing the thorax of a patient and forming an air-tight sealed chamber between the rigid shell and the thorax when the corset is attached to the patient; an inspiration tube connected at one end to the corset so as to communicate with the air-tight sealed chamber; a suction pump connected to the other end of the inspiration tube; and switching means mounted in a conduit of the inspiration tube so as to switch the connection of the inspiration tube between an atmosphere-opening side and a suction pump-connecting side. The artificial respirator further includes means for applying a fluid flow resistance to a fluid flow passage; and adjustment means for adjusting the variation speed of the air pressure. The adjustment means provides a flow capacitance having a compliance.
The means for applying the fluid flow resistance may be a throttle valve, an air filter, or a long spiral pipe, connected to the fluid flow passage. The means for applying the flow capacitance may be a sealed box connected to the fluid flow passage, an air-tight sealed chamber made of a resilient member and connected to the fluid flow passage, or may be a predetermined volume of space formed between the corset and the thorax.
With the above construction, the time constant of the variation in pressure within the corset can be adjusted to a suitable value by the adjustment means provided on the inspiration tube, thereby making gentle the speed of variation of the pressure within the corset. As a result, the patient is not subjected to an impact due to an abrupt variation of the pressure within the corset, and therefore the pain of the patient can be relieved.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described with reference to the drawings, wherein
FIG. 1 is a perspective view of a first embodiment of the present invention;
FIG. 2 is a graph showing a pressure waveform according to the invention;
FIG. 3 is a perspective view of a portion of a second embodiment of the invention;
FIGS. 4 to 6 show modified arrangements of the invention, respectively;
FIG. 7 shows a construction of a conventional artificial respirator; and
FIG. 8 is a graph showing a pressure waveform according to the conventional respirator of FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a first embodiment of the present invention. A corset 1 comprises a rigid shell 2 much like a tortoise shell, and a strap member (not shown). The rigid shell 2 has a shape adapted to enclose the thorax of a patient 3, and a packing made of a resilient material is secured to an inner surface of a peripheral edge portion of the rigid shell 2. The rigid shell 2 is adapted to be attached to the thorax of the patient 3 through this packing. The strap member is adapted to extend across the back of the patient 3 in such a manner that the opposite ends of the strap member respectively reach the surfaces of the opposite side portions of the rigid shell 2 attached to the thorax of the patient 3, and the strap member is adapted to be fastened to the rigid shell 2 by flat-type fasteners mounted respectively on the inner surfaces of the opposite side portions of the rigid shell 2. An inspiration tube 4 is connected at one end to a connection port provided in the rigid shell 2, and when the corset 1 is attached to the patient 3, the inspiration tube 4 is in communication with the air-tight chamber formed between the thorax of the patient 3 and the rigid shell 2.
An apparatus body 5 includes an air reservoir (adjustment means) 6 in the form of a sealed box, a three-way directional control valve 7, and a suction pump 8 all of which are received within a casing 9. The air reservoir 6 is in the form of a sealed cylinder. The other end of the inspiration tube 4 is connected to one end of the air reservoir 6 so that the air reservoir 6 is in communication with the interior of the corset 1 via the inspiration tube 4. A first pipe 10 is connected at one end to the other end of the air reservoir 6, and the other end of the first pipe 10 is connected to a first connection port of the three-way directional control valve 7. A second connection port of the three-way directional control valve 7 is open to the atmosphere via a second pipe 11, and a third connection port of control valve 7 is connected to the suction pump 8 via a third pipe 12. First and second throttle valves 13 and 14 are mounted on the second pipe 11 and the third pipe 12, respectively. By a valve actuator means (not shown), the three-way directional control valve 7 performs a switching operation by which the inspiration tube 4 is connected to the suction pump 8 or is communicated with the atmosphere.
The operation of the embodiment shown in FIG. 1 will now be described. First, the operator attaches the corset 1 to the patient 3, and connects the inspiration tube 4 to the connection port provided in the corset 1. At this time, the air-tight sealed chamber is formed between the rigid shell 2 of the corset 1 and the thorax of the patient 3. Also, the three-way directional control valve 7 is held in an atmosphere-opening condition in which the first and second pipes 10 and 11 are communicated with each other. Then, the operator turns on a power source of the apparatus body 5 to operate the suction pump 8, and at the same time the three-way directional control valve 7 is driven by the valve actuator means (not shown) so that the first pipe 10 alternately communicates with the second pipe 11 and the third pipe 12 in a predetermined cycle. By doing so, the air-tight sealed chamber in the corset 1 is brought alternately into a negative pressure and the atmospheric pressure, so that the artificial respiration of the patient 3 is effected in a predetermined cycle.
The time constant τ1 for the change from the negative pressure to the atmospheric pressure and the time constant τ2 for the change from the atmospheric pressure to the negative pressure are represented by the following formulas (1) and (2), respectively.
τ1=(C1+C2)R1 (1)
τ2=(C1+C2)R2 (2)
where C1 represents a compliance (volume/pressure) of the air reservoir 6, C2 represents a compliance of the air-tight sealed chamber of the corset 1 and the human body, and R1 and R2 represent fluid flow resistances (pressure/volume×velocity) of the first and second throttle valves 13 and 14, respectively.
Therefore, as compared with the case where there are not provided the air reservoir 6 and the throttle valves 13 and 14 as in the prior art, the time constants are increased because of the addition of a fluid flow capacitance, i.e., air reservoir 6 having compliance C1 and the throttle valves 13 and 14 having flow resistances R1 and R2, respectively. As a result, the variation of the pressure within the corset 1 when switching the fluid flow passage by the three-way directional control valve 7 is as indicated by a waveform in FIG. 2. Further, by suitably selecting the volume of the air reservoir 6 to adjust C1 and by suitably selecting the degree of opening of the throttle valves 13 and 14 to adjust R1 and R2, the time constants τ1 and τ2 can be adjusted to their respective optimum values.
In this embodiment, the speed of variation of the pressure within the corset 1 when switching the fluid flow passage by the three-way directional control valve 7 can be rendered gentle, and therefore the patient's pain can be lessened during the artificial respiration.
FIG. 3 shows a second embodiment of the present invention. In this embodiment, instead of the air reservoir 6 of the first embodiment, a long spiral pipe 15 is used as the adjustment means and is connected to the inspiration tube 4. The other parts are identical to those of the first embodiment.
In the embodiment shown in FIG. 3, by suitably selecting the length of the spiral pipe 15 and the degree of opening of the throttle valves 13 and 14, effects similar to those of the first embodiment can be achieved.
The arrangement of the air reservoir 6, the three-way directional control valve 7 and the throttle valves 13 and 14 shown in FIG. 1 may be modified as shown in FIGS. 4 to 6.
In FIG. 4, instead of the throttle valves 13 and 14 of FIG. 1, one throttle valve 14 is used and is mounted on a conduit between an air reservoir 6 and a three-way directional control valve 7, and a time constant is defined by the compliance of the air reservoir 6, the compliance of the sealed chamber of the corset 1 and the human body, and the fluid flow resistance of the throttle valve 14.
In FIG. 5, the air reservoir 6 is not included, however, the corset has a volume equal to the volume of the air reservoir 6 of FIG. 4, and a time constant is defined by the compliance of the corset and the fluid flow resistance of the throttle valve 14.
In FIG. 6, the corset has a volume equal to the volume of the air reservoir 6 of FIG. 1, and a time constant is defined by the compliance of the corset and the fluid flow resistances of the throttle valves 13, 14.
Another embodiment of the present invention is provided if, instead of each of the throttle valve 13 and 14, an air filter is used as the means for providing the fluid flow resistance.
Also, the present invention can be achieved if, instead of the air reservoir 6, an air-tight sealed chamber formed by a member in which all or a part thereof is made of a resilient material is used as the means for providing as fluid capacitance. In this case, the volume of the air reservoir 6 required for obtaining the same compliance as that applied by the sealed box made of a rigid member is less.
As described above, in the present invention, the adjustment means for decreasing the speed of variation of the air pressure is provided on the inspiration tube of the outside-of-thorax type negative pressure artificial respirator, and therefore the variation of the pressure within the corset can be made gentle during the artificial respiration, thereby lessening the pain to the patient. | An artificial respirator includes an atomospheric opening, a corset for enclosing a patient's thorax, an inspiration tube connected at one end thereof to the corset, a suction pump, a switching device for connecting the other end of the inspiration tube to either the suction pump or to the atmospheric opening so as to change the pressure within the corset between a negative and an atmospheric pressure, thereby providing artificial respiration to the patient. The artificial respirator further includes a device for varying the time constant of the change between the negative and atmospheric pressure within the corset so as to provide a smooth change between the pressures. | 0 |
BACKGROUND OF THE INVENTION
The present invention generally relates to prismatic galvanic cells, particularly those containing a significant number of electrode pairs.
EP-A-0 111 643 discloses an alkaline battery having cells which contain a relatively large number of electrode pairs. Separators are appropriately positioned between adjacent plates, in conventional fashion. Electrodes of the same polarity are in each case connected in parallel, and the parallel-connected, negative and positive electrode plates are in turn connected to terminal posts which extend through the wall of the cell. The individual cells are advantageously connected in series by connecting the terminal posts (of opposite polarity) of adjacent cells.
In cases where the individual cells contain a large number of electrode plates, the current tapping lugs of the electrode plates which are at a greater distance from the associated terminal post tend to be exposed to higher bending stresses. For this reason, the length of such lugs must be greatly increased. However, such lengthening of the lugs (to avoid increased bending stresses) is achieved either by preforming the lugs or by enlarging the terminal (or head) region, which are unfavorable conditions. For example, preforming of the lugs results in increased labor costs for assembling the cells, and lengthening of the lugs impairs the cell's volume capacity (typically expressed in Wh/l).
SUMMARY OF THE INVENTION
It is therefore the primary object of the present invention to increase the volume capacity of prismatic cells having larger numbers of electrode pairs.
It is also an object of the present invention to simplify the assembly of prismatic cells, while reducing the risk of short circuits between electrode plates of opposite polarity.
These and other objects which will become apparent are achieved in accordance with the present invention by providing the electrode plates of a prismatic cell with current tapping lugs which are formed as flexible tongues, defined by recesses in the upper or in the lateral edges of each plate, which extend generally parallel to the associated (upper or lateral) plate edges. The ends of the flexible tongues of the electrode plates of same polarity (all or groups) are in turn connected to their respective terminal posts. Such current tapping lugs make it possible to connect up to about 50 electrode plates (of one polarity) to the terminal post without requiring additional space for the resulting connection. The risk of a short circuit between electrode plates of opposite polarity is also reduced as a result.
For further discussion of the improvements of the present invention, reference is made to the detailed description which is provided below, taken in conjunction with the following illustrations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross-sectional view of a cell having current tapping lugs situated on upper edges of the electrode plates.
FIG. 2 is a transverse cross-sectional view of the cell construction of FIG. 1.
FIG. 3 is a plan view of an electrode plate used in the cell construction shown in FIGS. 1 and 2.
FIG. 4 is a longitudinal cross-sectional view of a cell having current tapping lugs situated on opposite sides of the electrode plates.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 and 2 show a prismatic cell 10 having electrode plates 1, 2 provided with a first embodiment of the current tapping lugs 3 of the present invention. As is usual for prismatic cells, the cell 10 has a relatively large number of electrode plates 1, 2 arranged in series. Separators are appropriately positioned between the plates 1, 2, in usual fashion.
Each of the electrode plates 1, 2 has a current tapping lug 3 which begins approximately in the center of the plate, and which extends along the upper edge of the plate toward one of the lateral edges. The lugs 3 of the plates 1 of one polarity extend toward one side of the series of plates, while the lugs 3 of the plates 2 of opposite polarity extend toward the opposite side of the series of plates, as shown.
The lugs 3 of the electrode plates 1, 2 are spaced from the center line of the plates 1, 2, and accordingly, the center of the upper plate edges. As a result, short circuiting between the positive and negative lugs 3 is effectively precluded. The lugs 3 are shaped to define recesses 4 along the upper plate edges, producing flexible tongues 5 which extend generally parallel to and above the upper plate edges. The flexible tongues 5 operate to accommodate the increased bending stresses typical of such cell constructions. The ends 7 of the flexible tongues 5 are connected to their respective terminal posts 6, preferably by ultrasonic welding.
FIG. 3 shows one of the electrode plates 1, 2 used in the cell construction of FIGS. 1 and 2, illustrating the recess 4 which operates to define the flexible tongue 5. As shown, the recess 4 is advantageously made wider near the end 7 of the flexible tongue 5 (at 8) than along the remaining (in-board) regions of the lug 3. Such broadening tends to reduce the risk of short circuiting in the vicinity of the terminal posts 6 because a sufficiently large distance is provided between the adjacent edges of the electrode plates and the terminal posts so that deviations during assembly, or shifting of the electrode plates, will not cause a short circuit.
The lugs 3 of the negative and positive electrode plates 1, 2 of the cell construction of FIGS. 1 and 2 are preferably arranged to extend from a position near the center of the upper plate edges, toward the opposite ends (lateral edges) of the series of plates. This arrangement is preferred if the electrode plates are substantially square, or if the electrode plates have a ratio of plate width to plate height (width/height) less than one. When the ratio of plate width to plate height (width/height) is greater than one (or if desired, when the plates are substantially square), the lugs 3 of the negative and positive electrode plates 1, 2 are preferably arranged on opposite sides (edges) of the electrode plates. Such a cell construction is shown in FIG. 4 of the drawings. The arrangement selected (top or side) is freely variable, and is responsive to the above-mentioned conditions to in each case permit the most favorable utilization of volume, and therefore achieve the greatest possible volume capacity.
The electrode plates of the present invention are especially useful in nickel-metal hydride or lithium-ion cells. In such cells, rolled expanded metal electrodes formed of copper, nickel, nickel-plated steel or aluminum, and foam or felt electrodes formed of nickel, nickel-plated copper or nickel-plated steel, are used as carriers of the active electrode material.
The lugs 3 are advantageously formed as an integral part of the carrier material of the electrode plates. However, a separate current conducting material may be affixed to the electrode plates, as an alternative. In such case, the material forming the lug 3 is preferably welded to a strip (edge) of the electrode plate which is free of electrode mass (e.g., when formed as a continuous ribbon).
The current-conducting structures of the electrodes preferably have thicknesses on the order of 100 to 500 μm. The resulting thickness of an electrode pair including a positive and negative electrode plate, and the corresponding separators, will be about 1 mm. As a result, 20 to 40, and preferably 25 to 30 electrode pairs can be installed in each cell.
In order to assure high mobility of the lugs 3, the flexible tongues 5 are preferably dimensioned so that their length is about 1/3 to 4/5 of the length of the corresponding edge of the electrode plate. The current conducting capacity of the lugs 3 is adjustable by varying the ratio (referring to FIG. 3) of the connected width (a) of the lugs 3 (connected with the edge of the electrode plate) to the width (b) of the flexible tongues 5. A ratio of about 5:1 is preferred. The electrode plates of the present invention are preferably produced by shaping the lugs 3 from the edges of the electrode plates, for example, by laser cutting or by stamping.
It will therefore be understood that various changes in the details, materials and arrangement of parts which have been herein described and illustrated in order to explain the nature of this invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the following claims. | A prismatic galvanic cell having a large number of electrode pairs separated by separators is provided with electrode plates having current tapping lugs which extend from upper or lateral edges of the plates, and which include flexible tongues extending along and parallel to the plate edges. The flexible tongues of grouped electrode plates of the same polarity are connected to the terminal posts of the cell in a manner which precludes short circuiting and which accommodates the increased bending stresses typical of such cells. | 7 |
BACKGROUND OF THE INVENTION
Each time a tank-type toilet is flushed, six to eight gallons of water go through the bowl and down the drain. The flushing of a toilet, in fact, consumes almost one half of the water used each day by a typical household--about 29 gallons of water per person is one estimate of the quantity. Because energy demands, and costs associated with water processing have increased substantially, there now exists a need to reduce the quantity of water used in all applications, including the flushing of toilets.
Numerous systems and devices have been proposed, and promoted, for reducing the amount of water used per flush of the toilet. These include smaller tanks, special valves, etc., all of which relate to controlling the amount of water entering the bowl. A review article describing typical devices, and their relative effectiveness, appears in Consumers Reports©, May 1979, beginning on page 296.
Whenever the volume of water dispensed into the bowl becomes too small, improper flushing occurs. By observation, I have determined that this is aggravated by the manner of distribution of water to the bowl surface, especially if non-uniform distribution occurs. Also, effective flushing action is reduced by swirling motion of water and waste against the bowl surface.
SUMMARY OF THE INVENTION
My water distributor for toilet bowls comprises a flexible, elongated channel element to be placed beneath the toilet rim in contact with the walls of the toilet bowl, this element having uniformly positioned, substantially annular external ridges whereby the space between the ridges directs water uniformly over the bowl surface.
BRIEF REFERENCE TO DRAWINGS
FIG. 1 is a drawing of my water distributor prior to insertion into a toilet bowl;
FIG. 2 is a cross section, as cutaway, showing my water distributor in position in a toilet bowl;
FIG. 3 is a drawing of another embodiment of my water distributor; and
FIGS. 4 and 5 are drawings of still other embodiments of my invention.
DETAILED DESCRIPTION
The simplicity of my water distributor is illustrated in FIG. 1. In this embodiment, a hollow cylindrical tubing 10 has, extending radially from its surface, uniformly spaced annular ridges 11. These ridges create valleys 12 therebetween, having walls substantially perpendicular to tubing 10, whose function is described hereinafter. Preferably, the ridges are integral with the tubing. The distributors are fabricated from a plastic having flexibility as a result of the composition and the ridged structure. A commercial ribbed tubing of an appropriate type is polyethylene "Corrtube" manufactured by O.E.M. Corp., Itasca, Ill.
One end 13 of the tubing 10 is closed with a plug 14 that extends whereby it may be inserted into the second end 15 of the tubing to form a closed loop. The length along the outer portion of the loop is made equal to the peripheral dimension of a toilet bowl immediately adjacent the rim. Different styles and makes of toilet bowls have different dimensions; therefore, the tubing length is determined for the particular unit before being joined into the loop and inserted into the toilet bowl. A typical length is about 110 cm.
Installation of my water distributor is shown in FIG. 2. Although bowls differ in detail, each type of toilet bowl has a water supply channel 16 within a rim 17. Small openings 18 communicate between this supply channel 16 and an inner surface 19 of the toilet bowl. The rim projects inward from this inner surface 19 forming an overhang having a bottom surface 20, as shown. My distributor fits immediately beneath the rim 17 whereby the annular ridges 11 are in contact with the bottom surface 20 and the inner bowl surface 19. As a result, the valleys 12 (see FIG. 1) serve as channels to downwardly direct water, entering through openings 18, uniformly over the inner bowl surface 19.
When properly positioned, as shown in this figure, the distributor is well above any waste in the bowl. Furthermore, it is not visible and therefore the color need not match that of the bowl. Because of its flexibility, however, it may be removed for complete cleaning of the bowl.
Other embodiments of my water distributor are depicted in FIGS. 3-5. In FIG. 3, the central channel 21 is substantially rectangular (e.g., square) in cross section, with the annular ridges 22 of like configuration (circular ridges could be used). FIG. 4 shows an embodiment wherein a cylindrical channel 23 is provided with an outwardly projecting spiral ridge 24 to perform a function similar to the ridge-valley construction of FIGS. 1 and 3. The embodiment in FIG. 5 utilizes an oval channel 25, the minor axis to be positioned perpendicularly to the bowl surface, having ridges 26 of uniform height.
The above-described embodiments indicate a hollow central channel. This is not a requirement of my invention although it does facilitate joining the ends (as in FIG. 1). For example, a solid core may create a spring-type effect to maintain the water distributor in proper position beneath the rim. This would eliminate joining the ends of the distributor.
The choice of materials of construction are primarily governed by the water environment: the properties of the material should not be affected by the frequent contact with household water and its common constituents. Suitable materials are ABS plastic, nylon, polypropylene, polyethylene, and like substances.
The dimensions of my distributor do not significantly influence performance when they are within certain limits. The afore-mentioned corrugated tubing, "Corrtube", that I utilize has an outside diameter of about 18 mm. The ridges are about 2 mm wide and are spaced apart about 1 mm. The depth of the valley is about 1.5 mm. Distributors of outer diameter less than about 10 mm are less effective for two reasons: some water entering through openings 18 may flow over the inner surface of the distributor; and the distributor may not have sufficient resiliency to maintain proper position within the bowl. Distributors of greater diameter may be used, with an upper limit of about 20 mm set by the appearance in the bowl since the overhang on bowls is 20-30 mm.
Ridges and valleys (corrugations) of the above dimensions are near the minimum as smaller channels would give excessive resistance to water flow. An upper range is near 5 mm for the ridge and valley width, as well as the valley depth. Larger dimensions will not overcome the swirling action in those bowls where the openings 18 are oriented to produce the same. Also, water may flow over the inner surface of the distributor and negate its function.
My water distributor assists in reducing the quantity of water used for flushing at least some types of toilets. In particular, considerable water velocity is lost in some bowls by the swirling of the water over the surface of the bowl. This loss of velocity is normally compensated for by using an additional quantity of water to properly clear the bowl of solids. My distributor orients the water flow more directly toward the outlet whereby a smaller quantity of water is required for adequate flushing action. As much as a 20% reduction in water has been demonstrated in a toilet of this type. Accordingly, the water storage tank of the toilet may be modified to hold a smaller volume of water for each flushing operation. Devices such as described in the aforementioned Consumer Reports reference may be used for the volume reduction.
From the foregoing it may be seen that my water distributor for toilets is simple, easily installed and effective to uniformly direct water down the inside of the toilet bowl. For many toilets, this redistribution of water substantially reduces the quantity of water needed to adequately flush the toilet. | A device is described which, when inserted under the rim of a toilet bowl in contact with the side wall thereof, uniformly distributes water over the surface of the bowl walls. This aids flushing material from the toilet. In many types of toilets, this also reduces the quantity of water required for each flushing operation. The device is flexible whereby installation and removal are facilitated in any shape of conventional toilet bowl. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a dental chair and an improved adjustment mechanism for the headrest of the chair.
2. Prior Art Relating to the Disclosure
Many of the chairs used by dentists and other professionals have adjustable headrest assemblies which are expensive to fabricate, cumbersome, inadequately adjustable and annoying to operate. It is also conventional for dental chairs to incorporate arm slings extending from the top of the back support of the chair to the arm supports, which keep the patient's arms and hands close to the body, out of the way of the technician or professional. The slings are always slipping loose and needing adjustment.
SUMMARY OF THE INVENTION
This invention relates to a dental chair incorporating an adjustable headrest which is vertically adjustable, adjustable about a central pivot point and adjustable both forward and rearward. The adjustable headrest comprises a support connecting to the back support of the chair at one end and to the adjustment mechanism at the opposite end. A padded headrest includes means connecting it with the adjustment mechanism. The adjustment mechanism includes: (1) an elongated linking member having upper and lower, variable size jaw openings therein receiving the connecting means of the support and the headrest; (2) a pin extending through the linking member holding the connecting means in place; and (3) means secured to the pin at one end contacting a camming surface on the linking member for contracting the jaw openings about the connecting means, preventing their movement.
The invention is also directed to a dental chair including integral, deflectable "wing" portions extending between the arm support and the top of the back support which (1) are flexible, (2) allow the dentist or technician to work closer to the patient, if desired, and (3) do not need adjustment.
The objects of this invention are: (1) to provide an improved adjustment mechanism for the headrest of a chair which is relatively inexpensive to manufacture, easy to operate and flush mounted to prevent interference with the dentist or technician and for design purposes; (2) to provide a dental chair incorporating an improved, flush mounted adjustment mechanism for a headrest; (3) to provide a dental chair incorporating flexible, deflectable wing portions which do not need adjustment and which allow the operator closer access to the patient sitting in the chair; and (4) to provide a dental chair having a back support hinged to the lower body support forward of the terminating edge of the lower body support, the back support having a curved, barrel-like appearance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the dental chair of the invention having a cut-away portion illustrating one of the flexible wings of the chair;
FIG. 2 is a rear elevational view of the headrest including the adjustment mechanism;
FIG. 3 is a vertical cross-sectional view along section line 3--3 of FIG. 2 illustrating the adjustment mechanism;
FIG. 4 is a horizontal cross-sectional view along section line 4--4 of FIG. 2; and
FIG. 5 is a partial cross-sectional view of the flexible wing portion of the chair.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a perspective view of the dental chair of this invention having a lower floor support 10 a padded lower body support 11 secured to the floor support 10 and a padded, integral back support 12 hinged at 21a to the lower body support forward of the rear terminating edge of the lower body support 11. The frames of the lower body support 11 and back support 12 are fabricated from steel plating one-eighth inch to five-sixteenths inch thickness over which is placed padding as an outer decorative upholstery covering, such as leather, naugahyde or vinyl. The back support has arm supports 14 attached at each side. Each of the arm supports includes a rigid steel frame, padding and covering similar to that of the lower body support and back support. Directly behind each of the arm supports is an arcuate member 15 secured to the frame of the back support, as illustrated by FIG. 1. A stiff, semi-rigid material, such as a thick plastic sheet 17, is stretched over the arcuate members and between the arm supports and the top of the frame of the back support prior to covering of the entire chair with the outer decorative covering, as illustrated by FIG. 5. The end result is a flexible, deflectable wing portion 16 beside each arm which does not need adjustment and allows the operator or technician to get closer to the patient sitting in the chair, if necessary. The wing portions can be deflected inwardly. On release of the deflector pressure, the wing portions will return to their original position due to the stiff material extending from the top of the back support over the arcuate portion 15 directly behind each of the arm supports 14. The rear of the back support includes a slot 18 for insertion of the adjustable headrest assembly to be discussed.
The adjustable headrest assembly is illustrated by FIGS. 2 through 4 and essentially comprises a headrest support frame 39 covered with a padded front portion 40 and a padded rear portion 41 connected by an adjustment mechanism to an elongated support plate 19. The headrest assembly is adjusted vertically relative to the back support by sliding in slot 18. The assembly is held in a desired adjustment position by a friction clamp (not shown). The supporting frame 39 of the headrest support has a center cut-out portion, as illustrated by FIG. 2, allowing the adjustment mechanism to be essentially flush mounted within the headrest assembly.
The adjustment mechanism comprises essentially an elongated, rectangular linking member 21 having bore openings 22 and 23 drilled therethrough at the upper and lower ends, respectively. Slots 24 and 25, cut in the link member 21, as illustrated by FIG. 3, communicate with the bore openings 22 and 23. The slot allows the internal diameter of the bore openings 22 and 23 to be reduced by compression of the linking member 21. A channel 26 is bored at transverse angles through the length of the linking member 21 to receive pin 30. The channel intersects the bore openings 22 and 23 and projects a small distance into the bore openings, as illustrated by FIG. 4. The bore openings 22 and 23 are fitted with pins 27 and 28, having an outer diameter slightly less than the internal diameter of the openings 22 and 23, so that they are free to rotate in the absence of compressive force on the elongated linking member 21, tending to reduce the internal diameter of the bore openings 22 and 23. Pin 27 consists essentially of two separate arcuate segments held in spaced relation by a rod 36 having a width less than the diameter of the pin 27. The rod 36 is secured to the segments by a pivot pin 37 extending through the rod, as illustrated by FIGS. 3 and 4. The pivot pin allows the rod to pivot thereabout between the positions shown in phantom in FIG. 4. The rod 36 is connected by collars 38 to the headrest support frame 39. The headrest can thus be pivoted about the pivot pin 37 to a desired position and locked in place, as will be described.
The lower pin 28 extends beyond the plane of the member 21 on each side and includes a slot extending part way therethrough which receives the forks 42 of support plate 19, as illustrated by FIG. 2. The pin 28 is secured in place to the plate 19 by bolts 43.
Each of the pins 27 and 28 has a central channel 29 cut therein, as illustrated by FIG. 4, of a depth sufficient to allow pin 30 to be inserted through the channel 26. The purpose of the channels 29, in cooperation with pin 30, is to secure the pins 27 and 28 in place in the linking member.
The pin 30, extending through channel 26 and securing the pins 27 and 28 in place, has a threaded portion 31 on the lower end over which is fitted a nut 32. The nut bears against a shoulder cut in the lower end of the linking member 21. The upper end of the pin 30 is pivotally connected to a cam member 34 bearing against a cam surface 33 cut in the upper end of linking member 21. The cam member 34 includes an integral handle 35 movable between the positions illustrated by FIG. 3. In the position shown in solid lines in FIG. 3, the pin in cooperation with the cam surface 34 exerts a compressive force on the respective ends of the linking member 21 compressing and closing the slots 24 and 25. As a result the internal diameter of openings 22 and 23 is reduced so that each frictionally engages the outer surfaces of pins 27 and 28 and prevents their rotation. When the handle 35 is moved to the position shown in phantom in FIG. 3, the compressive force on the linking member 21 is released, allowing the pins 27 and 28 to rotate freely within the bore openings 22 and 23.
The headrest portion of the adjustable headrest assembly can easily be adjusted relative to support plate 19 by moving the handle 35 to the position shown in phantom in FIG. 3 and rotating the headrest about either of the upper or lower pins 27 and 28 and pivoting the headrest about pivot pin 37 as desired. Once the desired position of the headrest is obtained, the operator presses the handle 35 down to the position shown in solid lines in FIG. 3 to lock all the components together and prevent further rotation or movement. The headrest can be adjusted to any desired position very easily and quickly. The adjustment mechanism is flush mounted within the headrest assembly, is simple to operate and is relatively inexpensive to fabricate. The dentist or technician can adjust the patient's head to any desired angle for mouth work or denture work very easily and without complication. | A dental chair is disclosed which has an adjustable headrest incorporating a flush mounted adjustment mechanism allowing (1) adjustment about a central pivot, (2) vertical adjustment or (3) forward and rear adjustment. The dental chair also incorporates deflectable "wing" portions adjacent each of the arm supports which do not need adjustment and which allow the dentist more ready access to the patient. | 0 |
NOTICE OF COPYRIGHT
[0001] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to any reproduction by anyone of the patent disclosure, as it appears in the United States Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE PRESENT INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to the technology field of friction material applied to a brake plate of the automotive braking system and preparation method thereof, and more particularly to an automotive asbestos-free and metal-free ceramic friction material and the preparation method thereof.
[0004] 2. Description of Related Arts
[0005] Friction materials containing asbestos, being forbidden, have been replaced by semi-metallic friction materials. Currently, low-metal friction materials have become mainstream products in the market. However the use of steel fibers as reinforcement fibers in semi-metallic and low-metal friction materials creates a several product defects. First, steel fibers rust easily, causing damage to the adhesive mating and decreasing the strength of the friction plate, whereupon the abrasion of the friction plate increases and the stability of friction coefficient deteriorates. Secondly, the thermal conductivity of semi-metallic and low-metal friction materials is high, while the semi-metallic and low-metal friction materials are pared off easily, such that the breaking system stops working. Thirdly, utilizing semi-metallic and low metal friction materials tends to generate low frequency noise. In order to solve the above-mentioned problems, it is highly desirable to develop organic friction materials free from asbestos.
[0006] Researchers have been unable to find a single type of fiber that has characteristics that can replace the use of steel fibers and asbestos fibers. Therefore, the researchers apply a variety of mixed fibers for combing the mechanical and physical properties of different fibers so as to enhance the frictional properties and performance of the non-asbestos friction materials. In addition, the mixed fibers are environmental friendly and popular in the market. However, the traditional resin non-asbestos, non-steel fibers friction materials utilize mass organic fibers, inorganic fibers having large specific surface areas, and fillers, so that a substantial amount of resin adhesive is needed for good adhesive performance. Therefore, the traditional resin friction material has poor heat fading resistance performance. The coefficient of the friction of the materials decreases depending on the proportion of non-steel fibers added therein. Seriously, abrasion and heat fading problems result from the utilization of more friction-increasing fillers. Hence, given the foregoing problems, it is important to improve the properties of friction materials that are free from asbestos and steel fibers.
SUMMARY OF THE PRESENT INVENTION
[0007] A main object of the present invention is to provide an automotive ceramic friction material free from asbestos and metal and preparation method thereof having high coefficient of friction, stable braking performance, low heat fading, low wear resistance and long service life.
[0008] According to the first preferred embodiment of the present invention, an automotive ceramic friction material, free from asbestos and steel fibers comprises the constituents of organic adhesive, reinforced fiber, friction-increasing agent, anti-friction agent, and fillers, wherein the weight percentage of organic adhesive is between 3% and 8%, the weight percentage of reinforced fiber is between 20% and 45%, the weight percentage of friction-increasing agent is between 3% and 12%, the weight percentage of antifriction agent is between 15% and 25%, and the weight percentage of fillers is between 10% and 30%. The sum of the weight percentage of all constituents is 100%.
[0009] As mentioned above, the organic adhesive can be one of phenolic resin and acrylonitrile-butadiene rubber, wherein the particle size of the phenolic resin is between 180 and 200 meshes, wherein the particle size of acrylonitrile-butadiene rubber is between 20 and 40 meshes.
[0010] Accordingly, the reinforced fiber must be at least two constituents of metal fibers, selected from the group consisting of copper fibers, aramid fiber, carbon fibers, mineral fibers, alumina fibers, and scaly potassium titanate, wherein the diameter of copper fibers is between 100 and 150 micron, wherein the diameter of aramid fibers and carbon fibers are less than 5 micron, and the length of aramid fibers and carbon fibers are between 300 and 80 micron, wherein the diameter of alumina fibers is between 120 and 180 micron, wherein the particle size of scaly potassium titanate is between 40 and 80 micron and the surface of the scaly potassium titanate is processed by the silane coupling agent.
[0011] Accordingly, the friction-increasing agent can be zirconium quartz, wherein the particle size of the zirconium quartz is between 30 and 50 micron. Besides, the zirconium quartz is soaked in the concentration of 60%˜80% of aluminum-chromium phosphate solution, and then the zirconium quartz is baked at the temperature between 200° C. and 500° C. for 1 to 3 hours so that the aluminum-chromium phosphate is coated on the surface of the zirconium quartz.
[0012] Accordingly, the anti-friction agent is a mixture including at least one of the antimony trisulfide and graphite, and the tin-sulfur-copper composite, wherein the anti-friction agent includes 10%˜40% weight percentage of the tin-sulfur-copper composite, wherein the particle size of the antimony trisulfide and graphite are between 40 and 74 micron, wherein the particle size of the tin-sulfur-copper composite is between 30 and 50 micron.
[0013] Accordingly, the fillers can be one of calcium carbonate and barium carbonate, wherein the particle size of calcium carbonate and barium carbonate are between 100 and 150 micron.
[0014] According to the second preferred embodiment of the present invention, a method of preparing an automotive ceramic friction material free from asbestos and steel fibers, comprises the steps of:
[0015] (1) preparing and mixing the constituents for the automotive ceramic friction material free from asbestos and steel fibers according to the pre-designed weight percentage so as to provide a mixture;
[0016] (2) heat molding the mixture in a pressuring mold at the pressure force between 200 and 500 kgf/cm 2 , the heating temperature between 160 and 200° C., the gas exhausting time between 3 and 8 times, and the ratio between time, thickness, and pressure between 60 and 75 second per millimeter calculating from the thickness of the mixture, so as to provide a molded mixture;
[0017] (3) heat processing the molded mixture according to the heating rate of 112° C. per minutes until temperature is at 140° C. and maintained for one hour, after that increasing the temperature continuously to 160˜180° C. for heat preserving for 4 hours, and then the temperature continuously increases depending on the heating rate of 0.5˜1° C./minutes until the temperature is at 210° C. in order to heat preserve for 4 hours; furthermore the molded mixture is cooled in the room temperature within the pressuring mold so as to provide a heat-processed molded mixture;
[0018] (4) heating the heat-processed molded mixture to a temperature between 650˜700° C. in order to process the high-temperature surface-ablation process, and then the heat processed molded mixture cools down within the pressuring mold so as to provide an automotive ceramic friction material, free from asbestos and steel fibers.
[0019] According to the above mentioned preferred embodiment, the friction increasing agent, defined as zirconium quartz with the aluminum-chromium phosphate coated thereon, and the anti-friction agent defined as a tin-sulfur-copper composite are defined as a ceramic surface-coating binder. The zirconium quartz is a conventional friction-increasing material, wherein the liquid aluminum-chromium phosphate solution is acidic so that the solidification of the phenolic resin provided from the alkaline catalyst is affected. Therefore, if the zirconium quartz powder is processed to an after-coating high-temperature baking process, the aluminum-chromium phosphate coated on the zirconium quartz will be heated and processed the first dehydration reaction. After the first dehydration reaction of the aluminum-chromium phosphate coated on the zirconium quartz, the acidity of the aluminum-chromium phosphate weakens, so that the network structure of the aluminum-chromium-phosphate-oxygen bond forms to soak the zirconium quartz. When the friction materials and mating plates are used at a temperature above 500° C., the organic adhesive resin rubber is heated to the point of loss of function. Continuously, the friction coefficient starts to decrease, and the recession appears. Therefore, the aluminum-chromium phosphate coated on the zirconium quartz starts to process the secondary cross-linked dehydration reaction. At the same time, the tin-sulfur-copper composite starts to melt so as to adhesively crosslink with the network structure of the aluminum-chromium-phosphate salt. Continuously, the network structure between the tin-sulfur-copper composite and aluminum-chromium-phosphate salt closely crosslinks, so that the friction materials tend to perform ceramic processing. Depending on the good friction performance of the zirconium quartz, the downward trend of the friction coefficient slowly decreases, so that the fading of the friction material declines also. At the same time, the adhesive strength of the friction materials can be maintained at the high temperature, so that the structure of the friction materials is compact. Therefore, the inner adhesive strength of the friction materials can be maintained while decreasing the abrasion loss of those materials under the high temperature.
[0020] Moreover, the tin-sulfur-copper composite includes stannic sulfide allay and cuprous sulfide. According to the adhesive characteristic of the melting sulfide at the high temperature, the tin-sulfur-copper composite can simultaneously perform the adhesion and lubrication effect. The surface of the friction plate forms a transfer film between the friction plate and mating plate so as to protect the mating plate during the friction action. Finally, the abrasion between the friction and mating plate efficiently decreases.
[0021] Especially, the automotive friction material according to the present invention has no asbestos and steel fibers, so it is harmless to the human body. At the same time, it eliminates the drawbacks of rust damage, mating damage, and braking noise generated from the rusting of the steel fibers. Furthermore, these friction materials provide an environmental friendly solution with excellent working performance.
[0022] According to the present invention, the automotive friction materials utilizes large amount of organic fibers, including mineral fibers, carbon fibers, alumina fibers, and scaly potassium titanate, along with the friction-increasing agent zirconium quartz of the organic ceramic adhesive coating so as to enhance the inner-bonding structure and increase the coefficient of friction of the materials. Obviously, this improves the low friction coefficient of the traditional NAO (non-asbestos organic) materials. In addition, when the anti-friction agent tin-sulfur-copper composite is added to the friction materials, the consequent high temperature melting status of the material has the result that the abrasion of the friction materials is more stable. This solves the aforementioned shortcoming of the traditional NAO materials having a short service life due to the high abrasion effects.
[0023] According to the preferred embodiment as mentioned above, the automotive ceramic friction material free from asbestos and steel fibers has a high friction coefficient, stable braking performance, low heat fading, low abrasion loss, and long service life. Wherein, compared to the traditional resin friction material free from asbestos and steel fibers, the ceramic friction material free from asbestos and steels fibers has the higher environmental-friendly performance, higher breaking stability, higher heat fading resistance, higher abrasion resistance, lower frequency noise, and no mating damage.
[0024] Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
[0025] These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a noise detection FIGURE for a sample provided from experimental group 4. FIG. 1 shows the noise testing for the sample provided from group 4, wherein the noise level is 10 defined as no noise.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Below will combine the preferred embodiment of the present invention, and further illustrate the methodological and compositional principles of the present invention. Six experimental groups are provided to illustrate the preferred embodiment, wherein the numbers of the six experimental groups are respectively 1, 2, 3, 4, 5, and 6. Another two groups, group 7 and group 8 are the control groups.
[0028] Accordingly, each example of the six examples utilizes the different proportions of constituents, which are
[0029] (1) Adhesive including the phenolic resin having the particle size between 180 and 200 meshes, and the acrylonitrile-butadiene rubber having the particle size of between 20 and 40 meshes.
[0030] (2) Reinforced fibers defined as at least two constituents mentioned below, including copper fibers having the diameter between 100 and 150 micron, aramid fiber (Dupont, Kevlar) having the diameter less than 5 micron and the length between 300 and 500 micron, carbon fibers having the diameter of less than 5 micron and the length between 300 and 500 micron, mineral fibers (Lapinus) having a diameter of less than 5 micron and the length between 300 and 800 micron, alumina fibers having the diameter between 120 and 180 micron, and scaly potassium titanate having the particle size between 40 and 80 micron and the surface of the scaly potassium titanate is processed by the silane coupling agent.
[0031] (3) Friction-increasing agent defined as zirconium quartz having the particle size between 30 and 50 micron. Besides, the zirconium quartz is soaked in the concentration of 60%˜80% of aluminum-chromium phosphate solution, and then the zirconium quartz is baked at the temperature between 200° C. and 500° C. for 1 to 3 hours so that the aluminum-chromium phosphate is coated on the surface of the zirconium quartz.
[0032] (4) Anti-friction agent composed of at least one of the antimony trisulfide and graphite, and the tin-sulfur-copper composite, wherein the anti-friction includes 10%˜40% weight percentage of the tin-sulfur-copper composite, wherein the particle size of the antimony trisulfide and graphite are between 40 and 74 micron, wherein the particle size of the composite of tin, sulfur and copper is between 30 and 50 micron.
[0033] (5) Fillers can be one of calcium carbonate having the particle size between 100 and 150 micron and barium carbonate having the particle size between 100 and 150 micron.
[0034] The particle size of the friction-increasing agent applying for group 7 and group 8 are between 30 and 50 micron, and the zirconium quartz is with no aluminum-chromium phosphate coated.
[0035] Group 1 and group 2 of the present invention apply the following preparation method. According to the pre-design weight percentage of all constituents for the friction materials, a mixture of the constituents is prepared. The mixture is molded in a pressuring mold at the pressure between 200 and 500 kgf/cm 2 , at a temperature between 160 and 200° C., the gas exhausting time between 3 and 8 times, and the ratio of time, thickness, and pressure between 60 and 75 second per millimeter calculated from the thickness of the mixture, so as to provide a molded mixture, after which the molded mixture is heated at the temperature of 140° C. under heating rate of 1˜2° C./minutes and maintaining that heat level for one hour, after that increasing the temperature continuously to 160˜180° C., maintaining that heat level for 4 hours, and then the temperature continuously increases at a the heating rate of 0.5˜1° C./minutes until the temperature is at 210° C. in order to heat and preserve for 4 hours; after which the molded mixture is cooled until the room temperature within the pressuring mold so as to provide a heat processed molded mixture. The heat processed molded mixture is heated to a temperature between 650 and 700° C. in order to process the high-temperature surface-ablation process, where after the heat processed molded mixture is cooled down within the pressuring mold so as to provide an automotive ceramic friction material free from asbestos and steel fibers.
[0036] Group 3 and group 4 of the present invention apply the following preparation method. According to the pre-design weight percentage of all constituents for the friction materials, a mixture of the constituents is prepared. The mixture is placed into a pressuring mold at the pressure between 200 and 500 kgf/cm 2 , the temperature between 160 and 200° C., the gas exhausting time between 3 and 8 times, and the ratio of time, thickness, and pressure between 60 and 75 second per millimeter based on the thickness of the mixture, so as to provide a molded mixture; that is then heated to the temperature of 140° C. at a heating rate of 1˜2° C./minutes and maintained for one hour, after that the temperature continuously increases to 160˜180° C. and maintained at that heat level for 4 hours, and then the temperature continuously increases at a heating rate of 0.5˜1° C./minutes up to a temperature of 210° C. in order to heat preserve for 4 hours; after which the molded mixture is cooled to the room temperature within the pressuring mold so as to provide a heat processed molded mixture. The heat processed molded mixture is heated to the temperature between 650 and 700° C. in order to facilitate the high-temperature surface-ablation process, and thereafter the heat processed molded mixture is cooled down within the pressuring mold so as to provide an automotive ceramic friction material free from asbestos and steel fibers.
[0037] Group 5 and group 6 of the present invention apply the following preparation method. According to the pre-design weight percentage of all constituents for the friction materials, a mixture is prepared of the constituents. The mixture is placed into a pressuring mold at a pressure between 200 and 500 kgf/cm 2 , a temperature between 160 and 200° C., the gas exhausting time between 3 and 8 times, and the ratio of time, thickness, and pressure between 60 and 75 second per millimeter calculating from the thickness of the mixture, so as to provide a molded mixture, and then the molded mixture is heated to the temperature of 140° C. according to the heating rate of 1˜2° C./minutes for heat preserving for one hour, after that the temperature continuously increases to 160˜180° C. for heat preserving for 4 hours, and then the temperature continuously increases depending on the heating rate of 0.5˜1° C./minutes until the temperature of 210° C. in order to heat preserve for 4 hours; furthermore the molded mixture is cooled until the room temperature within the pressuring mold so as to provide a heat processed molded mixture. The heat processed molded mixture is heated until the temperature between 650 and 700° C. in order to process the high-temperature surface-ablation process, and the heat processed molded mixture is cooled down within the pressuring mold so as to provide an automotive ceramic friction material free from asbestos and steel fibers.
[0038] Group 7 and group 8 of the present invention apply the same preparation method as group 3 and group 4.
[0039] Table 1 is the weight percentage of all constituents applied for experimental group 1 to group 6, and control group 7 and group 8.
[0000]
composition (%)
1
2
3
4
5
6
7
8
resin
8
8
5
5
4
3
5
4
aramid fibers
2
2
3
3
3
3
3
3
copper fibers
0
4
4
4
4
4
4
4
carbon fibers
4
0
5
5
6
7
5
5
mineral fibers
25
25
30
25
25
25
25
25
alumina fibers
0
3
10
3
3
3
3
3
scaly potassium
10
14
0
10
10
10
10
10
titanate
coated zirconium
3
5
7
9
10
12
0
0
quartz
zirconium quartz
0
0
0
0
0
0
5
7
tin-sulfur-copper
3
4
5
7
8
10
5
7
composite
antimony trisulfide/
15
15
15
15
15
15
15
15
graphite
fillers
29
20
18
14
12
8
20
17
[0040] According to the experimental group 1 to 6, the coated zirconium quartz with the aluminum-chromium phosphate coated thereon has a weight percentage between 3% and 12%, and the tin-sulfur-copper composite has a weight percentage of 3% and 10%. The zirconium quartz utilized by the control group 7 and group 8 have no aluminum-chromium phosphate coated. All of the constituents are uniformly mixed to manufacture a friction plate according to the preparation method of the preferred embodiment of the present invention, wherein the friction plate applied to the Honda Accord D 465 model is an example for the present invention.
[0041] Accordingly, each of the friction plate manufactured from the experimental groups are respectively processed the following tests, wherein a bench testing machine and a loading data collection system of NVH3900 manufactured by LINK are applied for testing the following performance:
[0042] (1) Fading Performance (SAE J2522, AK master, 100 km/h, 0.4 g deceleration rate)
[0043] (2) Braking Efficiency (SAE J2522, AK master, 80 km/h, 160 km/h, 200 km/h). Table 3 illustrates the data of the fading performance and braking efficiency.
[0044] (3) Noise Performance (SAE J2521)
[0045] (4) Abrasion Performance (SAE 2702) Wherein, table 2 illustrates the testing condition of the abrasion performance (SAE 2702)
[0046] As shown in table 3, with an increased content of the aluminum-chromium phosphate composite salt coated on the zirconium quartz, the friction coefficient of the friction material has an upward tendency, wherein group 2 to group 6 have the best braking stability, the friction coefficient of group 3 and group 4 are high and stable so that the fading of group 3 and group 4 are relatively small. The friction coefficient of group 5 and group 6 are so high as to cause other problems. The control group 7 and group 8 have the same content of zirconium quartz as group 3 and group 4, but the zirconium quartz are not aluminum-chromium phosphate composite salt coated. Therefore, the friction coefficient of group 7 and group 8 are relatively lower than group 4 and group 3, so that the stability of group 7 and group 8 are relatively poor, and the fading of group 7 and group 8 are relatively strong. Depending on the degree of increased content of the aluminum-chromium phosphate composite salt coated on the zirconium quartz, the friction coefficient of the friction material has an upward tendency, and the abrasion loss, also, is relatively in an upward tendency. In addition, if the ratio of the composite salt of the zirconium quartz is larger than 1.2, the abrasion loss is in an upward tendency.
[0047] As shown in FIG. 1 shows the noise testing for the sample provided from group 4, wherein the noise level is 10 defined as no noise
[0000]
TABLE 2
Braking
Braking
Initial
Final
Initial Disc
decel-
Fre-
Velocity
Velocity
Temperature
eration
quency
Parts
(km/h)
(km/h)
(° C.)
(g)
(N)
Run-in
50
4
100
0.25
100
Urban Road 1
50
4
150
0.25
200
(TB)1
Country Road
80
4
200
0.35
200
1 (CB)1
Country Road
100
4
125
0.40
200
2 (CB)2
Urban Road
50
4
150
0.25
200
2 (TB)2
Country
100
4
125
0.40
200
Road 3 (CB)3
Pathway
80
4
350
0.35
50
(HDB)
[0000]
TABLE 3
Abrasion(SAE
SAE
Fading rate
2707, one
J2522
80 km/h
160 km/h
200 km/h
(min)
circle)
1
0.36
0.32
0.28
0.20
0.97
2
0.38
0.35
0.32
0.23
0.82
3
0.40
0.38
0.38
0.26
0.65
4
0.42
0.40
0.42
0.30
0.58
5
0.44
0.43
0.42
0.31
0.77
6
0.45
0.43
0.43
0.33
0.93
7
0.37
0.33
0.30
0.19
0.89
8
0.40
0.36
0.34
0.24
1.13 | An automotive ceramic friction material free from asbestos and metal and preparation method thereof are provided. The material includes the following components: organic adhesive, reinforced fiber, friction-increasing agent, antifriction agent and fillers. The material has high coefficient of friction, stable braking performance, low heat fading, low wear resistance and long service life. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a method and apparatus for the coded transmission of messages by splitting up the clear (i.e. uncoded) signals to be transmitted into elements of equal length, which are transposed at the transmitting end by being delayed by at least partially different times and are transposed back at the receiving end by being further delayed by at least partially different times. The consecutively numbered elements e 1 , e 2 , e 3 , . . . of the clear signal x have coinciding lengths T o (see FIG. 1), and their transposition in time leads, for example, to the coded signal y, of which the first element e 4 appears undelayed at the moment t = 3T o , while the other elements appear with varying delay. After transmission of the signal y at a receiver, the elements are restored to their original position by retransposition in order to recover the original clear signal.
The elements e 1 , e 2 , . . . may, as shown in FIG. 2, be pulses of the duration T o , which are keyed between -1 and +1 or between 0 and 1 in accordance with a telegraphic message. Each element may, however, also comprise a plurality of individual pulses of a data signal s, as shown in FIG. 3. The pulses may also be quantized in a plurality of stages. The formation of elements, the amplitude of which corresponds to the scanned values, formed at intervals T o , of a continuously variable clear signal s (t), is shown in FIG. 4. Instead, however, sections of the clear signal s (t) of constant length T o may be formed as elements e 1 , e 2 , . . . as shown in FIG. 5. FIG. 5 also indicates that, instead of these continuously variable signal sections, a train of short individual pulses c (t) is suitable for forming the elements (see element e.sub. 3). Now, as a result of the encodingprocess, the sequence of such elements in time is altered, while the nature of the individual elements can remain unaltered.
Methods and devices for time coding, that is to say for the transposition in time of message elements, have become known for example through the Swiss Pat. No. 212,742 and 232,786, which describe how omissions and also repetitions of individual elements are avoided by periodically actuated switches. A periodic repetition of the transposition program effected at short intervals is undesirable, however, for cryptologic reasons. Accordingly, in the Swiss Pat. No. 518,658, a method is described which renders possible the control of the transposition process by random signals, as a result of which, periodic repetitions of the transposition program during a transmission are avoided. This control is achieved by means of a separate position register which, however, considerably increases the total expenditure necessary. The total expenditure on known devices is also comparatively heavy because the storage devices used are generally only partially filled with message elements wherein at least 50% of the stored locations remain unoccupied at any moment.
BRIEF DESCRIPTION OF THE INVENTION AND OBJECTS
According to the invention, these disadvantages are avoided by transposition in pairs of two elements at a time, which have a specific mutual spacing, at the transmitting end and retransposition of the same elements in pairs at the receiving end, the pairs of elements being transposed or retransposed at the transmitting end and at the receiving end being determined by irregular trains of control pulses which coincide at the two ends, and the elements which do not belong to the pairs of elements being delayed at the transmitting and receiving ends by a fixed time T, while the element of each pair which arrives first is delayed by double the time 2T at the transmitting and receiving ends and the second element is not delayed.
It is therefore one object of the invention to provide method and apparatus for encoding and/or decoding messages by transposing selected pairs of message elements while leaving remaining message elements untransposed.
Another object of the invention is to provide method and apparatus for encoding and/or decoding messages by transposing selected pairs of message elements so that one element of the pair undergoes a delay 2T and the remaining element of the pair undergoes no delay.
Still another object of the invention is to provide method and apparatus for encoding and/or decoding messages by transposing selected pairs of message elements so that one element of the pair undergoes a delay 2T and the remaining element of the pair undergoes no delay and wherein message elements not treated in pairs undergo a delay T, so that T = n T o where T o = message element length, and n = 1,2,3, . . . , n.
BRIEF DESCRIPTION OF THE FIGURES
The above, as well as other objects of the invention, will become apparent from the following description and drawings, in which:
FIG. 1 shows one manner in which message elements of a message may be transposed.
FIGS. 2 - 5 show waveforms of various message formats which may undergo encoding (and decoding) by the techniques and apparatus of the present invention.
FIG. 6 shows a circuit for carrying out the exchange of message elements in pairs,
FIGS. 7 and 8 are diagrammatical illustrations of the exchange of adjacent elements,
FIGS. 9 and 11 show circuits for obtaining control signals for the actuation of the transposition switch from cipher signals,
FIGS. 10 and 12 show examples of cipher signals and control signals obtained therefrom,
FIG. 13 shows a circuit for the transposition in pairs of non-adjacent elements with associated circuitry for obtaining the control signals,
FIGS. 14 and 15 are diagrammatic illustrations of the exchange in pairs of non-adjacent elements,
FIGS. 16 and 17 show a circuit for the repeated exchange in pairs with cipher-signal preparation and a circuit for the repeated re-exchange with cipher-signal preparation,
FIG. 18 is a diagrammatic illustration of the repeated exchange in pairs,
FIG. 19 is an illustration of the delay times which occur with repeated exchange in pairs,
FIG. 20 shows a circuit for permutation in accordance with a constant program,
FIGS. 21 and 22 are diagrammatic illustrations of permutations in accordance with a constant program,
FIG. 23 shows a block circuit diagram of devices for the time coding by element exchanges in pairs in conjunction with permutations in accordance with a fixed program and for the decoding by element exchanges in pairs in conjunction with permutations.
DETAILED DESCRIPTION OF THE INVENTION
An explanation of the invention will now be given with reference to FIG. 6, which shows a simple circuit for carrying out the exchange of elements in pairs. The circuit contains a retarder R with the transit time T o , which corresponds to the length of one message element. This retarder can be connected, through the switches H 1 , H 2 (in position "O", as shown), to the input line and the output line of the circuit so that one element at a time of the clear signal x is supplied to the retarder, while at the same time a stored or delayed element is extracted therefrom as output signal y. By means of a pulse of the control signal a with the duration T o , on the other hand, the switches are brought into the position designated by "I", so that one element of the input signal x at a time again appears directly as an element of the output signal y, while the preceding input element continues to be stored by being fed back from the output to the input of the retarder. The position of the beginning of the element in the retarder is indicated by the variable length d.
In the absence of a pulse of the control signal a, therefore, an element e 1 of the input signal x will reappear as element e 1 of the output signal y after the time T o , as shown in FIG. 7. In the course of the duration of the element e 6 , on the other hand, for example, a pulse of the control signal a appears so that this element reaches the output without delay, through the switch H 1 , (indicated in broken lines in FIG. 7), while the preceding element e 5 is fed back to the input of the retarder through the switch H 2 and therefore only reaches the output of the circuit after an additional delay time T o or with a total delay 2T o . The passage through twice can be recognized by the position d of the initial edge of the element, which can be seen from FIG. 7. Whereas the element e 1 is merely delayed by the time T o , therefore, a delay reduced to 0 has occurred with the element e 6 and a delay increased to 2T o with the element e 5 , so that these last two elements appear transposed in time in the output signal y. In a similar way, the pair of elements e 2 , e 3 is also transposed in time as shown in FIG. 7, while the element e 4 for example is transmitted with delay but without transposition with any other element. The same transpositions are indicated again diagrammatically in FIG. 8. It should be noted that the time zero has been advanced (i.e. shifted one "frame" to the left) by one time interval T o in the signal y in order to achieve a clearer illustration.
It should be noted that during the transposition in pairs as described, the switches H 1 , H 2 should never be actuated for longer than the duration T o of one element, in order that no element may be stored longer than 2T o . Accordingly, immediate repetitions (for example 00110) of the switching pulses are not permitted on the control signal a. In order to extract the control signals a o from a cipher-signal w o following a quasi-random course, a cipher-signal addition circuit SZ o as shown in FIG. 9 is therefore suitable. As a result of delaying each individual pulse of the cipher signal w o by the element length T o in the retarder V o , a blocking signal v o results which suppresses a possible following pulse of the cipher signal in the interrupter U o . The effect of this suppression is shown by way of example in FIG. 10. The suppressed pulses are designated by underlining. A disadvantage in this case, however, is that with an uninterrupted train of three or more pulses, all the pulses except the first are cancelled. This disadvantage is avoided with the cipher-signal addition circuit SZ 1 shown in FIG. 11, in which the interrupter U 1 is actuated by the pulses of the control signal a 1 delayed in v 1 . With an uninterrupted train of a plurality of pulses of the cipher signal w 1 , only every other pulse is suppressed in this case so that the control signal a 1 indicated in FIG. 12 results for example, and meets the requirements for an exchange of elements in pairs. In FIG. 11, apart from the device PT 1 already explained for the exchange of elements in pairs, a cipher-signal generator SG is indicated, the construction and mode of operation of which may correspond to known constructions. Devices for generating cipher signals with digital circuits are described for example in the Swiss Pat. No. 361,839.
Depending on the nature of the clear signals x, digital or analogue stores of known construction should be used as retarders R for exchanging the elements in the pair exchanger PT. In this case, it may be a question of delay lines or balancing networks, electro-mechanical retarders (for example acoustic systems) or electromagentic stores (for example magnetic sound recording with moving medium). Electrical shift registers are particularly suitable, with which signals keyed digitally (for example as shown in FIGS. 2 and 3) can easily be stored if operated at an appropriate clock frequency. With analogue signals (for example as shown in FIGS. 4 and 5), periodic scanning and storage of the scanned values (c(t) in FIG. 5) is necessary. These scanned values can also be converted, by binary coding, into corresponding pulse groups, the storage of which is then effected with digital stores having an appropriately larger number of stages. In this case, with the pair exchanger PT 1 shown in FIG. 11, it is necessary to connect an analogue-digital converted at the input side to extract digital input signals from the clear signal x and to connect a digital-analogue converter at the output side to extract output signals y in analogue form. Delta modulation is also possible, however, instead of the binary coding. The changeover switches H 1 , H 2 may appropriately be realized by suitably controlled semiconductor switching elements, which is also true for the interrupter U 1 in the cipher-signal addition circuit SZ 1 .
The effectiveness of the time coding is increased by transposition in pairs, of elements which are not immediately adjacent. In FIG. 13 a device PT 3 is shown for the transposition in pairs of two elements at a time, the beginnings of which have a mutual spacing of three element lengths T o , and corresponding element trains are illustrated in FIGS. 14 and 15 to explain the operation by way of example. When the switches H 3 , H 4 are in the normal position shown, the elements of the output signal y appear delayed by 3T o in comparison with the input signal x, if the delay of the retarder R 3 likewise amounts to 3T o . This is the case, for example, with the element e 2 (see FIG. 14), because said switches are in the normal position shown both during the supply and also during the extraction of this element. Although the element e 3 is likewise supplied to the retarder through the switch H 3 , nevertheless after a first passage through this retarder, it is again fed back to the input of the retarder through the switch H 4 , because at this time, this switch is brought into the operative position (not shown) by a pulse of the control signal a 3 . At the same time, an element e 6 of the input signal x is conveyed, without delay to the output through the switch H 3 which is likewise actuated (indicated in broken lines in FIG. 14). Only three element lengths later does the stored element e 3 finally appear through the switch H 4 restored to the normal position, in the output signal y. In a similar manner, the elements e 1 , e 4 and e 7 , e 10 for example are also transposed, while e 5 and e 8 are passed on with simple delay without being transposed. This process is illustrated again, with the associated control signals, in FIG. 15. The advancing of the time zero (i.e., the shifting left of the time frame) should again be noted in this simplified illustration. As a result of operation with control pulses having the uniform length T o , the effect is achieved that a plurality of elements of corresponding length always travel through the retarder.
In order to avoid a further feedback of all elements which have already been delayed twice, care must be taken to ensure that no further pulse follows a pulse of the control signal a 3 with the spacing 3T o . For this reason there is provided in the cipher-signal addition circuit SZ 3 , a blocking switch U 3 which is actuated by the pulses of the control signal a 3 delayed by three element lengths T o in V 3 , so that any following inadmissible control pulses are eliminated. Here, too, the cipher signals w 3 , from which the control signals a 3 are obtained by suppression of inadmissible pulses, are taken from a cipher-signal generator SG.
In order to further increase the effectiveness of a time coding, the interconnection of a plurality of pair-exchange process circuits is advisable so that an increase in the possible displacements of each element comes about. In FIG. 16, a device ZT can be seen in which a first transposition in pairs is effected of elements of the clear signal x through the retarder R 3 and the switches H3, H4, as a result of which a signal y results, the elements of which may have additional displacements by 3T o or 6T o as in FIGS. 13 and 15. A second transposition in pairs is then effected through the retarder R 1 and the switches H 1 and H 2 with smaller displacements similar to FIGS. 6 and 8. The cipher-signal addition circuit SZ is also equipped with retarders V 3 and V 1 respectively, corresponding to FIGS. 13 and 11 respectively, in accordance with the unequal displacement times. This cascade connection of two transposition processes in pairs produces, from a clear signal x, the element numbers of which are designated by n(x) in FIG. 18, first the intermediate signal y, of which the element numbers n(y) are likewise given in FIG. 18, and finally, as a result of further element exchange in pairs, the output signal z with the element numbers n(z). Whereas displacements of 0 and +3 element lengths occur in the intermediate signal, the second exchange produces displacements of 0, +T o , +2T o , +3T o , +4T o can appear in the output signal z in comparison with a mid position of the elements. In view of the fact that even this mid position has a displacement of 4T o , because negative displacements in time are impossible, the output elements of the time coding device ZT therefore appear with delays of O, T o , 2T o 3T o , . . . to 8T o in comparison with the input elements. The delays occurring in the example shown are given in FIG. 19 as integral multiples r(n) of the element length T o over the element numbers n of the input signal x. It can be seen that a very effective mixing of all the elements of the message comes about already as a result of pair exchanging twice. This process could be extended by one or more further pair exchanges. In this case, it is advisable to avoid the same storage times for the various exchange processes. The number of possible displacements becomes particularly high if the storage times are graduated in accordance with a ternary system, in that retarders are used having transit times of T o , 3T o , 9T o . . . =3 i T o (i = a whole number), because thus all total delays mT o between 0 and (3 k +1 - 1)T.sub. o are possible (m = a whole number, k = total number of the pair transposition devices).
A device which as shown in FIG. 17, corresponds largely to the transposition device at the transmitting end, serves for the re-exchange of the message elements at the receiving end. From the coded signal z* received, which coincides with z, as a result of a first re-exchange with the retarder R* 1 and the switches H* 1 , H* 2 , an intermediate signal y* is again formed which coincides with y and (apart from the delay of the transmission channel) is delayed by 2T o in comparison with y, because the untransposed elements are subjected to a delay of T o at the transmitting end and at the receiving end. With the transposition of the elements e 5 and e 6 shown in FIG. 7, re-exchange of these elements comes about when a following analogue transposition device receives a control pulse a at the moment the element e 5 is received, so that this element is not further delayed, while the preceding element e 6 is delayed by 2T o and so comes back into the original position in relation to e 5 . Accordingly, the control pulses a* 1 of the first re-exchange with the switches H* 1 , H* 2 must be displaced by T o in comparison with the control pulses a 1 of the exchange shown in FIG. 16 with the switches H 1 , H 2 , in the device also shown in FIG. 17. This displacement is achieved by an additional delay T o of the cipher signal w* 1 at the receiving end (FIG. 17). In this case, it is assumed that the cipher-signal generator SG* at the receiving end is synchronized with the cipher-signal generator SG at the transmitting end by auxiliary signals u and u* transmitted separately, for example by the method described in the Swiss Pat. No. 361,839. In the case of element exchange in pairs with displacement by three element lengths as shown in FIGS. 13 and 14, it should be noted that an element e 3 which is displaced by six element lengths in the exchange process at the transmitting end (see FIG. 14), must not be further delayed during the re-exchange at the receiving end, while the element e 6 which is not delayed at the transmitting end has to be delayed by six element lengths at the receiving end. The control pulse for the re-exchange at the receiving end must therefore coincide with the element e 3 received; that is to say the control of the re-exchange must be delayed by 3T o in comparison with the control at the transmitting end, if no additional delays have to be taken into consideration. In the transmission system as shown in FIGS. 16, 17, however, as already explained, there is a difference in time of 2T o between the signals y and y*, so that the control signal a* 3 for the re-exchange in pairs in the retarder R* 3 , the transit time of which amounts to 3T o , must be delayed altogether by 3T O + 2T O = 5T o in comparison with the control signal R 3 for the exchange in pairs in R* 3 . The retarder W* 3 is provided in the cipher-signal addition circuit SZ* at the receiving end to ensure this delay time (FIG. 17).
The effectiveness of an enciphering by exchanging elements in pairs is also increased by additional permutation of the elements in accordance with a fixed program. A device ZT o , which is suitable for this, may contain two retarders R 1 , R 2 with an identical transit time, as shown in FIG. 20. Individual elements of the input signal y 1 can be supplied to these retarders through the switches A 1 and B 1 respectively, while the extraction of elements to form the output signal y 2 is possible through the switches A 2 and B 2 respectively. When the switches are not actuated, however, the retarder output is connected back to its input in each case. Finally direct passing-on of elements of the input signal y 1 to the output of the device is possible through the further switches C 1 , C 2 . The switches A 1 , A 2 are always actuated simultaneously, likewise the switches B 1 , B 2 and C 1 , C 2 , for example in accordance with the periodic program S given at the top in FIG. 21 (the switches not recited in a time interval being in the normal position in each case). The elements of the input signal y 1 are numbered consecutively with the numbers given below the switch program S in FIG. 21. The switching through by the switch C is indicated diagrammatically underneath (DC). The element No. 3 is passed on directly through the switch C to the output so that this element appears without delay in the output signal y 2 (FIG. 21 bottom). The element No. 5 on the other hand, passes through the simultaneously actuated switch A 1 to the retarder R 1 (the delay in R 1 is illustrated symbolically in the next line "VR 1 "), and immediately after being delayed only once, it is conveyed to the output through A 2 . The input element No. 4, which reaches the retarder R 2 through the switch B 1 (see next line "VR 2 "), on the other hand, is fed back from the output of the retarder to the input thereof through the switches B 1 , B 2 which alternate in the normal position after this input; it is only extracted therefrom again after passing through three times and added to the output signal y 2 , as soon as the switches B are actuated again. On the assumption that the transit time of a retarder R coincides with the element length T o , such storage and switching-over finally leads to an output signal y 2 with elements transposed in time, as can be seen from the resulting numbering shown at the bottom of FIG. 21.
Mutual displacements of the elements by greater times are possible with an increased transit time of the registers R. With a delay time 3T o of the registers R 1 and R 2 , the displacements which can be seen from FIG. 22 result, as the switch control is effected in accordance with program S given across the top of FIG. 22. The element No. 2 for example is transmitted directly through switches C 1 , C 2 while the element No. 3 is delayed by three element lengths in the retarder R 1 . The element No. 5, on the other hand, after being fed back twice, is subjected to a delay of 9T o in the retarder R 2 . The element No. 4 is subjected to a delay of 6T o in the same retarder and the element No. 1 is actually delayed by 12T o in R 1 . Because of the periodic repetition of the switching-over program, the elements No. 1, 6, 11 . . . are delayed by the same amounts, likewise the elements 2, 7, 12 . . . and the elements 3, 8, 13 . . . and so on. Further possibilities for carrying out the periodically repeated transposition are provided, for example, by increasing the delay times of R 1 and R 2 to 4T o or even greater amounts, or by using three or more retarders which are connected to the inputs and outputs of the device in a similar manner by switches actuated in pairs.
An interconnection of the device ZT o , which has been explained, for the periodically repeatd permutation of message elements, with devices PT 1 and PT 2 for the exchange of such elements in pairs, is shown in FIG. 23. The control-signal additions for obtaining the control signals a 1 and a 2 from the cipher signals w 1 and w 2 are designated by circuits SZ 1 and SZ 2 . A further control-signal addition circuit SZ o serves to produce the periodically repeated control signals a o for the actuation of the switches A, B, C of the permutation device ZT o . The corresponding devices at the receiving end for reversing the transpositions and the signals appearing in the course of this are shown in FIG. 23 using the same symbols. An additional asterisk (for example y* 2 ) serves to make a distinction from the devices and signals at the transmitting end. The transit times of the retarders contained in PT 1 and PT 2 are preferably selected unequal in order to obtain, once again, as great a multiplicity as possible of the element displacements which can be achieved.
The interconnection described, between devices for exchanging elements in pairs and a device for permutating elements in accordance with a fixed program, leads to resulting transpositions of the message elements which are still very difficult to take in at a glance even with knowledge of the fixed permutations. In particular, the fact should be noted that the number of possible displacements of elements is considerably greater than with simple exchange of elements in pairs and that the total expenditure necessary remains comparatively low because even with the permutations, operation involves optimum utilization of all signal stores.
Supplementing the exchange of elements in pairs by an additional time coding of known type is, of course, also possible. In this case, too, the individual transposition operations at the receiving end must be provided in reverse sequence compared with the transmitting end. There is also the possibility, however, of an effective amplification of the exchange of elements in pairs according to the invention by enciphering processes of another kind, such as additional splitting up of the elements into individual frequency bands which are transmitted in a transposed frequency position. In particular, there is also the possibility of a division into two or more frequency bands, which are each subjected, independently of one another and in accordance with a different program, to a time coding by exchange of elements in pairs. Thus apart from at least two devices for the exchange of elements in pairs, separate filters for dividing the message into at least two sub-bands are necessary for carrying out such enciphering.
The effectiveness of the exchange of elements in pairs can also be increased by interconnecting two or more devices for the exchange of elements in pairs, working with different lengths of element. The element lengths are preferably in an integral ratio to one another so that at least some of the element dividing points are common to the longer and shorter elements.
Instead of a direct transmission of the coded signals from the device at the transmitting end to that at the receiving end, provision may also be made for recording the coded signals at the transmitting end, for example a sound-tape recording. This recording can then be played back again at a later time and be supplied to the deciphering device at the receiving end to recover the original clear signals.
Although this invention has been described with respect to its preferred embodiment, it should be understood that many variations and modifications will now be obvious to those skilled in the art and, therefore, it is preferred that the invention be limited not by the specific disclosure herin but only by the appended claims. | Method and apparatus are disclosed whereby messages are encoded by message element exchangers which utilize a delay device for transposing selected pairs of message elements so that the first element of the pair undergoes a delay 2T and the remaining message element of the pair experiences no delay. Message elements not treated in pairs undergo a delay T. The delay T is an integral multiple of the duration of a message element (said elements preferably being of equal length T 0 ). Transmitted messages which have undergone selective transposition are decoded in a similar fashion, whereby the undelayed message element of a pair undergoes a delay 2T, the remaining element of the pair undergoes no delay and messages elements not treated in pairs undergo a delay T.
Exchangers of dissimilar delay periods may be connected in cascade to enhance the number of possible delay displacements which message elements may undergo. Also exchangers may be adapted to utilize plural delay devices to provide for further permutation of message elements. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/141,480 filed on Dec. 30, 2008. The disclosure of this provisional application is incorporated by reference in its entirety.
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to artificial lift devices and methods, and more specifically, to Electric Submersible Pumps (ESP) and methods for lubricating and protecting ESP.
[0004] 2. Background Art
[0005] In oil wells and the like from which the production of fluids is desired, a variety of fluid lifting systems have been used to move the fluids to surface holding and processing facilities. Electric submersible pump (ESP) is a common equipment used to pump the subterranean formation fluids to surface for transport to processing locations.
[0006] FIG. 1 shows a conventional pumping system 10 disposed in a wellbore. The pumping system 10 typically includes at least an electric submersible pump 12 (such as a centrifugal pump), a submersible motor 14 , and a motor protector 16 . Because the wellbore fluids usually contain deleterious substances, such as muds, sands, barite, and similar particulate and non particulate matters, the main purpose of the protector 16 is to protect the motor 14 by preventing the well fluids from entering the motor 14 . In addition to functioning as a seal, the protector 16 also serves as an oil reservoir and pressure equalizer for the motor 14 to balance the internal pressure of the motor 14 with respect to the outside pressure in the wellbore.
[0007] The pumping system 10 is deployed in a well 18 penetrating a geological formation 20 containing desirable production fluids, such as petroleum. In a typical application, a wellbore 22 is drilled and lined with a casing 24 . The casing 24 may include a plurality of openings 26 , through which production fluids can flow into the wellbore 22 .
[0008] The pumping system 10 is deployed in the wellbore 22 by a deployment system 28 , which may have a variety of forms and configurations. For example, the deployment system 28 may include tubing 30 connected to the pump 12 by a connector 32 . Power is provided to the submersible motor 14 via a power cable 34 coupled to a submersible component, e.g., the motor 14 , by a power cable connector or a pothead 35 . The motor 14 , in turn, powers the centrifugal pump 12 , which draws production fluid in through a pump intake 36 and pumps the production fluid to the surface via the tubing 30 .
[0009] A submersible pump motor often contains an internal motor fluid that is protected from the surrounding well fluid. In addition, the submersible motor is exposed to substantial differential pressures between its interior and the surrounding environment during movement downhole and during operation downhole. The downhole environment can be very hash, with temperatures higher than 250° C. and pressures higher than 30,000 psi. Therefore, a motor protector is typically coupled to the submersible motor to protect the motor from deleterious wellbore fluids and to balance undue pressure differentials.
[0010] Many types of motor protectors have been designed for incorporation into electric submersible pumping systems. The motor protectors typically comprise one or more sections that can change conformation or volume to reduce differential pressure while maintaining a barrier between the internal motor fluid and the surrounding wellbore fluid. For a discussion of ESP protectors, please see U.S. patent application publication No. 2007/0224056, by Watson et al.
[0011] Even with protectors, ESP systems are eventually damaged after certain service lives in downhole environments. Typical run lives of electric submersible pumps (ESPs) may be several hundred days, depending on the formations. In very harsh environments, the service lives of ESPs would be expected to be much shorter. Common damages to ESPs may include degradation of elastomers used as seals in motors or protectors. In addition, degradation of the oils used in the motor and/or protector can also shorten the service lives of ESPs.
[0012] The moving parts in an ESP motor or protector rely on lubricant oils to maintain proper functions. Generally, either mineral oils or synthetic oils, such as poly-alpha-olefin (PAO) oils, are used in ESP motors and protectors. These mineral and PAO oils are selected for their desirable properties. The following are some properties relevant to ESP motor oils (many of these properties are interrelated):
[0013] Dielectric strength—A high dielectric strength, typically 25 KV, may beneficially provide a secondary electrical insulation for the motor windings, terminals and leads. Mineral and PAO oils can provide excellent dielectric strength, when they are new. However, the dielectric strength of these oils would be decreased by bearing wear particles and dissolved water coming from slight ingress of well fluids through worn shaft seals.
[0014] Viscosity—Mineral and PAO oils generally have sufficient viscosity to protect the bearings in the motor and protector from wear by establishing an adequate thickness of the oil film separating the bearing components. However, long term exposure to elevated temperature gradually breaks down the viscosity of mineral and PAO oils. For example, the mineral and PAO oils tend to suffer excessive loss of viscosity at temperatures above 550° F.
[0015] Lubricity—Mineral and PAO oils can provide sufficient lubricity to the bearings in the motors and protectors to prevent wear by reducing the coefficient of friction between the bearing components when they are not separated by a full fluid film. However, long term exposure to elevated temperature gradually breaks down the lubricity of mineral and PAO oils. For example, most mineral and PAO oils may suffer loss of lubricity at temperatures above 550° F.
[0016] Specific gravity—When a specific gravity of oils is distinctly different from the well fluids, it may allow the use of gravity separation chambers in a protector to exclude well fluids from ESP motors. Mineral and PAO oils generally have specific gravities of around 0.82, which is useful for gravity separation from water. However, the gravities of most mineral and PAO oils are very close to the densities of many types of crudes. Therefore, this property of mineral and PAO oils may limit their use in gravity separation chambers in high water-cut wells.
[0017] Immiscibility—The oils that is immiscible with well fluids may allow the use of gravity separation chambers to exclude well fluids. Although mineral and PAO oils may be very immiscible with water, they are quite miscible with many types of crudes. Again, this property of mineral and PAO oils would limit their use in gravity separation chambers in high water-cut wells.
[0018] Thermal stability—Mineral and PAO oils should retain adequate protection properties during both short-term and long-term exposure to elevated service temperatures to extend ESP life. However, long term exposure to elevated temperature would gradually break down the viscosity and lubricity of mineral and PAO oils. For example, these oils typically suffer excessive loss of viscosity and lubricity at temperatures above 550° F.
[0019] Chemical stability—Mineral and PAO oils should not be degraded significantly by slight contamination with well chemicals, such as gases and well fluids, which may migrate through the seals in the motors or protectors. In addition to solubility of water and crude, mineral and PAO oils also react with H 2 S, and they carbonize excessively at high temperatures.
[0020] Inert to other components—Mineral and PAO oils should not react with other components of the motors and protectors, such as metals, elastomers and polymers, especially at elevated temperature and pressure. However, mineral and PAO oils would attack (degrade) many elastomers at temperatures above 550° F.
[0021] Clearly, there is a need for better motor oils having most of these properties described above to improve the range and scope of ESP applications.
SUMMARY OF INVENTION
[0022] One aspect of the invention relates to electrical submersible pumps (ESPs) for use in a wellbore. An ESP in accordance with one embodiment of the invention includes a submersible pump; a motor; and a protector operatively coupled to the motor to protect the motor, wherein at least one of the motor and protector is filled with a PFPE oil.
[0023] Another aspect of the invention relates to methods for manufacturing an ESP for use in a wellbore. A method in accordance with one embodiment of the invention includes assembling the ESP from a pump, a motor, and a protector, wherein the protector is operatively coupled to the motor for the protection of the motor; and filling at least one of the motor and protector with a PFPE oil.
[0024] Another aspect of the invention relates to methods for pumping a fluid from a wellbore using an ESP. A method in accordance with one embodiment of the invention includes disposing the ESP in the wellbore; and operating the ESP, wherein the ESP comprises a pump, a motor, and a protector, and wherein at least one of the motor and protector is filled with a PFPE oil.
[0025] Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0026] FIG. 1 shows a typical electrical submersible pump (ESP) system disposed in a wellbore.
[0027] FIG. 2 shows an ESP in accordance with one embodiment of the invention.
[0028] FIG. 3 shows an ESP with a sectional view of the protector in accordance with one embodiment of the invention.
[0029] FIG. 4 shows an ESP with a power cable and a metal tube attached to a pothead on the motor in accordance with one embodiment of the invention.
[0030] FIG. 5 shows a flowchart illustrating a method for making and using an ESP in accordance with one embodiment of the invention.
DETAILED DESCRIPTION
[0031] Embodiments of the invention relate to methods and systems for lubricating and protecting ESP components using Perfluoropolyether (PFPE) oils. The following description concerns a number of embodiments and is meant to provide an understanding of the invention. The description is not meant to limit the scope of the invention.
[0032] PFPE oils are clear colorless fluorinated synthetic oils. They are inert, nonflammable, safe, and long lasting. PFPE are also referred to as perfluoroalkylether (PFAE) or pertluoropolyalkylether (PFPAE). They are available from various commercial sources, including Du Pont (Delaware, NJ), Solvay Solexis (Italy), Daikin (Japan), and NOK (Japan). For a review of PFPE oils, see Gregory A. Bell ad Jon Howell, “ Perfluoroalkylpolyethers ,” in “ Synthetics, Mineral Oils, and Bio - Based Lubricants: Chemistry and Technology ,” (Leslie R. Rudnick, Editor), Chapter 8, pp. 157-174, CRC Publishing, 2005.
[0033] PFPE includes four types of oils that are commercially available. These different types of PFPE oils have similar physical and chemical properties. However, they may have slight differences in their properties due to the difference chemical structures:
[0000] PFPE-K CF 3 CF 2 CF 2 O—[CF(CF 3 )CF 2 —O—] n CF 2 CF 3
[0000] PFPE-Y CF 3 O—[CF(CF 3 )CF 2 —O—] y —[CF 2 —O—] m CF 3
[0000] PFPE-Z CF 3 O—[CF 2 CF 2 —O—]) y —[CF 2 —O—] m CF 3
[0000] PFPE-D CF 3 CF 2 CF 2 O—[CF 2 CF 2 CF 2 —O—] n CF 2 CF 3
[0034] wherein n is 10-60, and (y+m) is 10-60. In general, the molecular weights of these PFPE oils are in the range of 435 to 13,500. In addition, PFPE oils may be functionalized to include one or two functional groups attached to the end of the chain. Such functionalized PFPE oils have better anti-corrosion properties and are available from commercial sources. In this description, “PFPE oil” is used in a general sense to include such functionalized PFPE oil or non-functionalized PFPE oil.
[0035] The polymer chains in these PFPE oils are completely saturated, and these oils contain only carbon, oxygen, and fluorine. On a weight basis, typical PFPE oils contain about 21.6% carbon, 9.4% oxygen, and 69.0% fluorine.
[0036] PFPE oils are superior to mineral and PAO oils in all of the relevant properties discussed above. For example:
[0037] Dielectric strength—PFPE oils have higher viscosity and lubricity than mineral and PAO oils. Thus, PFPE oils would produce less bearing and shaft seal wear. Less wear may result in lower contamination of the oils with metal wear particles and well fluids, thereby preserving the dielectric strength of the PFPE oils.
[0038] Viscosity—PFPE oils are available in a wide range of viscosities. PFPE oils would lose less viscosity than mineral and PAO oils would, after short-term or long-term exposure to temperatures above 550° F.
[0039] Lubricity—PFPE oils would lose less lubricity than mineral and PAO oils would, after short-term or long-term exposure to temperatures above 550° F.
[0040] Specific gravity—The specific gravity of PFPE oils is approximately 2. Therefore, they can be easily separated from both water and many types of crudes by gravity separation.
[0041] Immiscibility—PFPE oils are immiscible with either water or many types of crudes. This would facilitate their separation from these other fluids.
[0042] Thermal stability—PFPE oils break down less than mineral or PAO oils at high temperatures. Therefore, they can provide long-term protection even when used at high temperatures.
[0043] Chemical stability—PFPE oils are not attacked by chemicals typically found in oil wells. In addition, their stability makes it possible to recycle the PFPE oils and reuse them after the units have been pulled from the well to offset the costs.
[0044] Inert to other components—PFPE oils would not attack elastomers at temperatures above 550° F.
[0045] Based on these advantageous properties, embodiments of the invention may include systems and methods that use PFPE oils to improve the performance of ESP components in the following aspects:
[0046] (1) PFPE oils may be used for their advantageous dielectric strength, viscosity, lubricity, specific gravity, immiscibility, thermal stability, chemical stability and inertness in motors and protectors to extend the useful life of ESPs at internal temperatures below 550° F., in either vertical or horizontal installations. At below 550° F., PFPE oils still provide superior properties, even though other mineral or PAO oils may also work in these temperature range.
[0047] The only known use of PFPE in ESP is in barrier fluid protectors. In barrier fluid protectors, the barrier fluids are be utilized to improve the performance of the motors because they are used only for excluding well fluids. As such, the barrier fluids do not contact the motors at all. Thus, the barrier fluids do not contact the protector bearings or seals. The use of PFPE in ESP motors and protectors, in accordance with embodiments of the invention, expands the use of PFPE oils beyond this known use in ESPs.
[0048] FIG. 2 shows an ESP in accordance with one embodiment of the invention. As shown, a submersible centrifugal pump 12 is operatively coupled to a protector 16 , which is operatively coupled to a motor 14 . The protector 16 and the motor 14 may be connected in tandem in either vertical or horizontal installations. Either the protector 16 or the motor 14 or both may be filled with PFPE oils. Thus, the protector 16 and the motor 14 may benefit from the superior properties of PFPE with regard to insulation life, bearing life and seal life.
[0049] (2) PFPE oils may be used for their advantageous dielectric strength, viscosity, lubricity, specific gravity, immiscibility, thermal stability, chemical stability and inertness in motors and protectors to allow ESPs to perform reliably at internal temperatures above 550° F., in either vertical or horizontal installations. At internal temperatures above 550° F., PFPE oils are much better choice than mineral or PAO oils because mineral and PAO oils tend to degrade at such high temperatures.
[0050] This aspect of the invention takes advantage of the unique properties of PFPE oils above 550° F., where the properties of mineral and PAO oils may be very marginal. For example, at temperatures above 575° F., mineral and POA oils may be totally unsuitable. Unlike mineral and POA oils, PFPE oils would not break down and would not attack elastomers at those high temperatures. As shown in FIG. 2 , in accordance with embodiments of the invention, the protectors 16 and/or the motors 14 may be filled with PFPE oils.
[0051] (3) PFPE, oils may be used for straight gravity separation of well fluids in motors and protectors in relatively vertical wells at any temperature, because of their high specific gravity (density) and immiscibility with well fluids (water or crudes).
[0052] This aspect of the invention may eliminate the need for structures, such as reverse gravity separation chambers (labyrinths), rubber bladders (bags), and/or barrier fluid chambers, which are subject to failure. The PFPE oils-filled straight gravity chambers can simplify the construction of protectors.
[0053] FIG. 3 shows a sectional view of a protector in an ESP system in accordance with one embodiment of the invention. As shown, a submersible centrifugal pump 12 is operatively coupled to a protector 16 (a cross-section view is shown). The protector 16 is operatively coupled to a motor 14 . The protector 16 and the motor 14 may be filled with PFPE oils.
[0054] The protector 16 has a chamber 11 , which may be a simple straight housing of length adequate for the vertical thermal expansion and contraction of the PFPE oils (a straight gravity separation chamber). A shaft tube 13 and a shaft seal 15 may be used to prevent the shaft 17 from imparting rotation to the fluids in the chamber 11 . This may avoid mechanical mixing of the PFPE oils with the well fluids, thereby preventing centrifugation of the PFPE oils out of the top of the chamber 11 .
[0055] Because PFPE oils are much denser than the well fluids, the shaft seal 15 may no longer be critical because any well fluids that leak into the protector 16 may not sink down through the PFPE oils to the motor 14 . When the motor 14 heats up, the levels of the RITE oils rise; when the motor 14 cools, the levels of the PFPE oils fall. Thus, the well fluids may be effectively separated from the PFPE oils due to the unique physical properties of the PFPE oils, such as high specific gravity and immiscibility with well fluids.
[0056] (4) PFPE oils may be used to exclude well fluids and to pressure balance potheads with motors and protectors in relatively vertical wells at any temperature, because of their high specific gravity.
[0057] In accordance with embodiments of the invention, the potheads may feature oil-tilled metal tubes that can be welded to the top end of the potheads and extended over the cables up past the top end of the protectors. These metal tubes may serve to pressure balance the protectors and the motors.
[0058] FIG. 4 shows a pumping system, illustrating a pothead attached to a motor, in accordance with one embodiment of the invention. As shown, a submersible centrifugal pump 12 may be operatively coupled to a protector 16 . A metal tube 41 may be attached and sealed, as by welding or a tube fitting, to the upper end of a pothead 45 , which is attached to the motor 14 . A power cable 43 is connected through inside of the metal tube 41 to the motor 14 via the pothead 45 . The power cable 43 is disposed in the metal tube 41 to form an annular space 47 between the OD (outside diameter) of the power cable 43 and the ID (inside diameter) of the metal tube 41 .
[0059] In a vertical wellbore application, the metal tube 41 may extend upward to a height exceeding the height of the protector 16 in the well. The upper end 49 of the metal tube 41 may be open to the wellbore. At installation and before running the ESP into the well, the metal tube 41 may be tilled with PFPE oils. After installation, the protector 16 , the motor 14 , the pothead 45 , and the metal tube 41 effectively act as an “U”-tube, tending to maintain the same level of the PFPE oils in the metal tube 41 and the protector 16 . The PFPE oils in the metal tube 41 would prevent well fluids from reaching the pothead 45 because PFPE oils have a much higher specific gravity than well fluids. As a result, if there is any leakage developed in the seals at the pothead 45 , the well fluids may not enter the pothead 45 or the motor 14 .
[0060] The levels of PFPE oils may rise and fall at thermal expansion and contraction, respectively. Because of the “U” tube configuration, although the levels of PFPE oils in the metal tube 41 and the protector 16 may rise and fall according to thermal expansion and contraction, the levels of PFPE oils in the metal tube 41 and the protector 16 may remain the same.
[0061] Because the upper end 49 of the metal tube 41 is open to the wellbore, initial discharge of excess PFPE oils to the wellbore may happen due to thermal expansion. However, subsequent loss of PFPE oils to the wellbore through the pothead 45 may be greatly reduced. Neither would there be any ingress of well fluids at the pothead 45 .
[0062] Some embodiments of the invention relate to methods for making and using the pump systems described above. For example, FIG. 5 shows one method for making and using a submersible pump (e.g., an ESP) in accordance with one embodiment of the invention. As shown in FIG. 5 , a method 50 for making and using an electrical submersible pump systems in a wellbore may include the following steps: Obtain an ESP without oils filled in the motor and/or protector. (step 52 ). Then, fill the ESP motor and/or protector with a PFPE oil to produce an ESP of the invention. (step 54 ). Such an ESP is then deployed in a wellbore for its intended operations. (step 56 ). Then, the ESP is run to pump a fluid from the wellbore to the surface. (step 58 ).
[0063] Advantages of embodiments of the invention may include one or more of the following. By tilling the motors and/or protectors with PFPE oils in ESP systems, the reliability of such ESP system is increased. At the same time, the operating costs of these systems are reduced because of the extended useful life of the ESP systems at all temperatures. In addition, because of the high specific gravity and immiscibility with well fluids, PFPE oils may be used for straight gravity separation of well fluids in motors and protectors in relatively vertical wells at any temperature. This simplifies the design of protectors. Furthermore, because of the high specific gravity, PFPE oils may be used to exclude well fluids and pressure balance potheads with motors and protectors in relatively vertical wells at any temperature.
[0064] While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | An electrical submersible pump (ESP) for use in a wellbore includes a submersible pump; a motor; and a protector operatively coupled to the motor to protect the motor, wherein at least one of the motor and protector is filled with a PFPE oil. A method for manufacturing an ESP for use in a wellbore includes assembling the ESP from a pump, a motor, and a protector, wherein the protector is operatively coupled to the motor for the protection of the motor; and filling at least one of the motor and protector with a PFPE oil. A method for pumping a fluid from a wellbore using an ESP includes disposing the ESP in the wellbore; and operating the ESP, wherein the ESP comprises a pump, a motor, and a protector, and wherein at least one of the motor and protector is filled with a PFPE oil. | 4 |
FIELD OF THE INVENTION
The invention relates to camouflage material and in particular, camouflage material which is suitable for clothing, coverings for blinds and tarps.
BACKGROUND OF THE INVENTION
Generally, camouflage material is used to allow a person or an object to avoid detection by people, animals or machines. Various means of camouflaging people or objects are known in the wildlife hunting/observing, fishing and military fields. For example, hunters use camouflage techniques and materials which break up the outline or the surfaces of a person or object. The camouflage often functions by the use of varied colors and/or designs on the material to break up this outline or surface of the person or object.
The colors used on the camouflage material often are similar to the natural environment in which the material is used. Such camouflage material is particularly suitable for use in military applications. Additionally, there are circumstances where a person desires not to be seen by wildlife animals and, for safety purposes, to be seen by other people. Specifically, persons viewing or hunting wildlife animals desire to approach the wildlife animals without being detected. At the same time, these persons also desire to make themselves visible to other people nearby who may mistake them for a wildlife animal. Both of these objectives are possible because many animals only detect shapes and shades of grey, but detect colors poorly. For example, U.S. Pat. No. 4,868,019 to Knickerbocker discloses a camouflage system for visually concealing people and objects from animals wherein the selection of colors to be used depends on the extent of the animals color vision and the reflectivity of the colors used. All the images make use of more than one color to break up the image of the person wearing the camouflage article. Further, the designs depicted on the material vary and include abstract or random objects; or objects found in the environment wherein the camouflage material is used; or depict photographic images placed on the material.
Other known camouflage materials use three dimensional surfaces to break up the outline or the surface of the person or object sought to be camouflaged. For example, U.S. Pat. No. 4,517,230 to Crawford discloses an artificial leaf for camouflaging hunter's clothing and equipment by providing a three dimensional effect to destroy his silhouette and make him less visible and suspicious to game. Other camouflage materials have three dimensions where the material has partial cuts which rise from the plane of the material to create an added dimension. For example, U.S. Pat. No. 4,323,605 to Rush discloses camouflage material having V-shaped cuts to provide concealment for people and equipment from people or animals having a sense of color or geometric perception.
The problem of concealing persons or objects continues to challenge. To date, three dimensional camouflage clothing has proven inadequate for many applications because it fails to take into account a variety of environments in which the camouflage material is used. For example, wildlife observation and hunting take place in the animal's habitat during varied weather conditions. Thus, clothing often brushes or rubs against trees, branches, bushes and is worn in rain or snow. The prior art three dimensional camouflage material, such as the camouflage wraps or wherein cuts are made to break up the image, are likely to catch on trees, branches or bushes a wildlife observer or hunter may encounter.
Further, the prior art three dimensional camouflage material such as cuts and camouflage wraps fail to protect the object or person from the weather elements, such as rain or snow, which may be encountered and may even trap or retain rain or snow.
As a consequence, there is a need for camouflage material directed to overcoming these and other disadvantages of the prior art.
SUMMARY OF THE INVENTION
The camouflage material of the present invention comprises a substantially continuous sheet. The substantially continuous sheet has a pattern which extends from the plane of the sheet. The pattern can be formed by affixing a fold in the sheet which creates an affixed and unaffixed portion of the pattern.
In one embodiment, the pattern includes two substantially continuous lines. Further, the substantially continuous lines can have one or more branches extending from the substantially continuous lines. The intersection of continuous lines can be defined by an affixed portion of the first line intersecting an unaffixed portion of the second line. Alternatively, the intersection of the continuous lines can be defined by an unaffixed portion of the first line intersecting an unaffixed portion of the second line. In other embodiments, the pattern is a plurality of substantially continuous lines.
The camouflage material of the present invention can be used for clothing. The clothing articles may include shirts, pants, vests, jackets, coveralls, rain gear, gloves, mittens and headwear. Further, clothing articles can be water repellant. The camouflage material of the present invention may have artificial foliage elements attached to the pattern on the sheet. The artificial elements may include flowers, leaves, weeds, tree limbs, brush limbs and ferns.
The camouflage material of the present invention can comprise two or more different colors. The colors on the sheet can be different shades of blaze orange. The camouflage material of the present invention can comprise a sheet having a photographic image. The photographic image can be woods, trees, tree bark, branches, brush, plants, and grass.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further advantages thereof, reference is now made to the following Detailed Description taken in conjunction with the accompanying Drawings, in which:
FIGS. 1 illustrates various examples of patterns comprising curved and straight lines and curved and straight lines comprising one or more curved or straight lines branching therefrom;
FIG. 2 illustrates a preferred pattern to be used in the wildlife animal's habitat or environment;
FIG. 3 illustrates a preferred pattern to be used in the wildlife animal's habitat or environment;
FIG. 4 is a cross section of a preferred pattern;
FIGS. 5A and 5B are a cross section of various ways to extend a pattern from the plane of the sheet;
FIGS. 6A-6D are a perspective view and a cross sectional view of one preferred way to form a pattern;
FIG. 7 is a perspective view of a pattern comprising a straight continuous line and further comprising a second continuous line branching or intersecting said first continuous line;
FIG. 8 is a perspective view isolating the affixed and unaffixed portions of the pattern;
FIGS. 9A and 9B illustrate a garment having a pattern;
FIG. 10 illustrates a pattern having multiple substantially continuous vertical lines further comprising a plurality if second continuous lines branching from the substantially vertical continuous lines;
FIG. 11 illustrates a pattern comprising multiple continuous lines, with and without branches, randomly distributed.
DETAILED DESCRIPTION
The present invention is directed toward a three dimensional camouflage material which comprises a substantially continuous sheet having a pattern on it wherein the pattern extends from the plane of the sheet. The camouflage material of the present invention has many uses including articles of clothing, coverings for blinds or other objects and tarps.
In accordance with one aspect of the present invention, the sheet is substantially continuous. Significant advantages are achieved by the sheet being substantially continuous. Often a user of camouflage material, such as a wearer of clothing made from it, brushes against various types of foliage when hunting, for example. If the camouflage material is not substantially continuous and thus, has significant openings, such openings are likely to catch on foliage and tear the camouflage material and/or cause undesirable noise which reveals the user. Further, openings in camouflage material allow moisture to readily penetrate the materials thereby requiring the user to make use of other means to provide moisture protection.
The sheet of the present invention, being substantially continuous, has substantial portions of the sheet which have no openings and thus have continuity. The remaining portions of the sheet can include the areas of openings such as the cuts or slits found in prior art camouflage material discussed above. The sheet of the present invention is considered to be a substantially continuous sheet if the portion of the sheet having no openings comprises at least about 50% of the surface area of the sheet, more preferably, at least about 90% of the surface area of the sheet, and even more preferably, at least about 95% of the surface area of the sheet.
It should be noted that many products made from the camouflage material of the present invention can include portions of the product in which the material is discontinuous. For example, clothing articles made from the camouflage material often comprise button holes or snaps to affix the clothing article to the wearer or various pockets and loops to contain items needed by the wearer of the clothing article. Such material and products are considered to be substantially continuous and thus, within the scope of the present invention. Further, the sheet of the present invention is considered to be substantially continuous regardless of whether the sheet is one piece of material or numerous pieces of material attached together with substantially no openings. For example, clothing articles made from the camouflage material of the present invention can comprise several pieces of material attached together by, for example, sewn seams. Such articles are considered to be substantially continuous and thus, within the scope of the present invention.
The sheet can be any of numerous materials. Preferably, the material selected for the sheet is adaptable for use as clothing and has resiliency against moisture and tearing. A non-exhaustive list of materials suitable for the sheet include natural products, such as cotton and wool, synthetic resins, water repellant materials, such as GORE-TEX® 1 or rubberized material, or combinations thereof.
Another important aspect of the present invention is that the camouflage material is three dimensional. As discussed above, it is desirable that the material be capable of breaking up the outline or surface of the person wearing, or the object covered by, the camouflage material. The camouflage material of the present invention breaks up the outline or surface, at least in part, by a three dimensional effect created by a pattern on the sheet extending from the plane of the sheet. As will be discussed in more detail below, there are a variety of ways for a portion of the sheet to extend from the plane of the sheet.
In this manner, the camouflage material of the present invention creates a significant camouflage effect because the added dimension provides depth of field and texture to the camouflage material. Further, the added dimension can create shadows on the material by natural light hitting the portion of sheet which extends from the plane of the sheet. The shadow effect causes various color shades which serve to further break up the continuity or visual image of the outline or body surface of the user or object.
A further aspect of the present invention is that the portion of the sheet which extends from the plane of the sheet forms a pattern. The pattern can be any visual image which serves to break up the outline or surface of the person wearing, or the object covered by, the material. For example, one pattern is a substantially continuous line defined by the raised area of sheet which is substantially continuous between two points on the sheet.
In this manner, the pattern formed by the raised area can take many forms. The pattern formed may comprise one or more curved and/or straight lines. The pattern formed may also comprise one or more curved and/or straight lines, branching from other curved and/or straight lines. FIG. 1 illustrates various examples of curved and straight lines and curved and straight lines further comprising one or more curved and straight lines branching therefrom.
The pattern formed may also comprise any geometric shape. For example, the pattern formed may comprise one or more circles, triangles, ovals and the like in various combinations. Further, the pattern formed may comprise one or more abstract images or contorted geometric shapes.
Further, the pattern formed may comprise images which simulate images naturally found in wildlife animal's habitat or environment, such as trees, bushes or grasses. For example, as shown in FIG. 2, the pattern would mimic or represent various motifs in the habitat or environment, e.g. deciduous growth, by straight continuous lines oriented in a substantially vertical manner. Preferably, more than 50% of the straight continuous lines are oriented between 45 degrees and 135 degrees on a 0 to 180 degree horizontal reference. More preferably, more than 75% of the short straight continuous lines are oriented between 45 degrees and 135 degrees. Another example is shown in FIG. 3, where a pattern comprises continuous lines oriented in a substantially horizontal manner. Preferably, more than 50% of the short straight continuous lines are oriented between 0 to 45 degrees and 135 to 180 degrees on a 0 to 180 degree horizontal reference. More preferably, more than 75% of the short straight continuous lines are oriented between 0 to 45 degrees and 135 to 180 degrees.
Further, the pattern formed may comprise one or more of various images described above at varying densities.
In accordance with another aspect of the present invention, the pattern discussed above extends from the plane of the sheet. With reference to FIG. 4, a cross section of a preferred pattern, later described, on the sheet is shown. The plane of the sheet 20 refers to the primary surface of the camouflage material. For example, in a garment or cover such as shown in FIG. 9, the plane of the sheet 20 is the exterior surface of the garment as it hangs or is draped over the body.
The term "extends" refers to the pattern being sufficiently raised from the plane of the sheet to make visible shadows caused by the pattern at various times of daylight. The length of extension takes into account various factors associated with the environment in which the material is used including the type and density of foliage likely to be encountered by the user as well as the weather conditions, including the amount of sunlight. The pattern preferably extends from the plane of the sheet by at least a 1/16", more preferably by at least about an 1/8" and even more preferably by at least about a 1/4".
The pattern on the material extending from the sheet can be formed in a variety of ways. In general, the extension of the pattern from the plane of the sheet is formed by affixing portions of the sheet or pieces of material on the sheet. Affixing can be accomplished in any suitable manner, including stapling, sewing and gluing. For example, as shown in FIG. 5A, the cross section of one embodiment of the pattern shows that the pattern can be formed by affixing a separate, detached piece 30 of material at the plane 31 of the sheet to cause a raised area 32. Further, as shown in FIG. 5B, the pattern can be formed by a separate, detached piece 33 of the sheet positioned in an opening in the plane of the sheet and affixing the separate and detached piece of the sheet with the plane of the sheet at the opening. As discussed above, the substantially continuous nature of the sheet is not affected by separate, detached pieces of sheet being affixed to other portions of the sheet and thus, such embodiments are within the scope of the present invention.
In a preferred embodiment, the pattern is formed by gathering a portion of the sheet from the plane of the sheet to cause a portion of the sheet, formerly part of the plane of the sheet, to extend from the plane of the sheet as a fold. For example, in FIGS. 6A-6D a straight continuous line pattern 40 is formed by gathering a portion of the sheet so that a fold 41 in sheet is formed and affixing a folded portion of the sheet along a line at the plane 42 of the sheet. The fold in the sheet causes overlapping portions of the sheet defined by either side of the fold.
Preferably, the overlapping portions of the sheet caused by the fold in the sheet are affixed at various points along the continuous line as shown in FIG. 6C. Thus, a line of a pattern can have an affixed portion 42 and an unaffixed portion 43 with the unaffixed portion 43 being folded and raised from the general plane 44 of the material by virtue of an adjacent folded affixed portion 42. More preferably, as shown by FIG. 6C and the cross-section view of an affixed portion of the fold in FIG. 6D, the overlapping portions of the sheet caused by the fold 41 in the sheet are affixed at various points where the fold 41 immediately begins to extend from the plane of sheet 44.
Referencing FIG. 7, a pattern of the present invention can include a straight continuous line 50 and further comprise a second straight continuous line 51 branching from or intersecting the first continuous line. The first continuous line 50 is formed as generally described above with reference to FIG. 6. Preferably, the second continuous line 51 is formed by gathering a portion of the sheet so that a fold in this sheet is formed and the overlapping portions of the sheet are affixed at various points. Preferably, an unaffixed portion of the second continuous line intersects either an affixed or unaffixed portion of the first continuous line. More preferably, as illustrated in FIG. 8, the intersection of the two continuous lines is defined by one of the folds being affixed 60 and the other fold being unaffixed 61 at the intersection. The result is a less rigid area at the intersection of the continuous lines which is sufficiently flexible to allow the tree and brush branches to slide on the sheet without catching, tearing or creating undesirable rustling. If, on the other hand, the first and second continuous lines intersect at affixed portions, the intersection of the respective folds is a stiff and substantially rigid area. Such areas are not preferred because they are susceptible to catching tree and bush branches and/or collecting moisture such as rain or snow.
The camouflage material of the present invention may be used for garments and articles of clothing such as shirts, pants, vests, jackets, coveralls, rain gear, gloves, mittens or headwear. FIGS. 9A and 9B respectively show the front and back of a jacket having a pattern comprising a plurality of continuous lines which are align substantially vertically with the wearer of the garment and which are substantially parallel to each other. Additionally, any of the other patterns as broadly described herein are suitable as well. Further, the camouflage material of the present invention may be used for covers for blinds used by hunters or covers over objects. In addition, the camouflage of the present invention can be used in a variety of military applications. In its various applications, the camouflage material of the present invention may have a pattern which runs up against a border of, for example, a garment. Preferably, a continuous line of a pattern is not affixed at the intersection of the continuous line and the border of a garment.
With reference to FIG. 10, a further embodiment is a pattern having multiple substantially continuous vertical lines 80 with a plurality of second continuous lines 81 branching from or intersecting the substantially vertical continuous lines 80. It is a further embodiment that at least a portion of the plurality of second continuous lines 81 are angled from the substantially vertical continuous lines 80 at about the same angle. In a still further embodiment, the pattern comprises multiple, randomly angled lines. As shown by FIG. 9, it is still a further embodiment that the pattern comprises multiple continuous lines, with and without branches, randomly distributed.
Any of the embodiments of the camouflage material described herein can also further have a means where articles may be attached to the camouflage material. The articles can be anything which will assist in further breaking the outline of the object or person. Such articles can be artificial foliage elements or geometric shapes such as circles, rectangles or other multi-sided figures. Examples of foliage elements include flowers, leaves, weeds, tree limbs, brush limbs and ferns.
The camouflage material of the present invention can be any color. For example, the material may comprise one or more colors found in the environment in which the material is used, such as brown, green or beige. In this manner, the material will provide additional camouflage effect. Also, the material can include bright colors, such as blaze orange or neon colors. The use of two or more colors further breaks up the outline of the wearer of the garment making use of the camouflage material in addition to the three dimensional pattern. In a further embodiment, the portions of the material which form the pattern are a different color than the plane of the sheet.
A further embodiment of the invention is to use camouflage material as broadly described above, wherein the material is a bright color, such as blaze orange. Such an embodiment is particularly useful for applications involving the hunting or observing of wildlife because most animals cannot detect such bright colors but rather only perceive various shades of gray. Thus, the use of bright colors allows for the user of the camouflage to be more readily detected by other humans while still being effective camouflage for animals due to the three dimensional patterns. In a variation of this embodiment multiple bright colors or shades of bright colors are used. Thus, a further camouflage effect is obtained due to the pattern created by use of multiple colors. For example, multiple shades of blaze orange can be used. In this manner, compliance with many states' hunting regulations can be achieved while having significant camouflage effect. Some states require certain amounts of continuous blaze orange on hunters during some hunting seasons.
A further embodiment is that the sheet used in any of the embodiments described herein include photographic images which have been transferred to the sheet. The photographic image can consist of various images in nature. Such images can include woods, tree bark, branches, brush, plants and grass. A still further embodiment is that the portions of the sheet which form the raised pattern substantially coincide with the photographic image found on the sheet. In this embodiment, for example, a continuous vertical line could represent the tree trunk and other continuous lines intersecting the continuous vertical line would represent the tree branches.
While various embodiments of the present invention have been described in detail, it is apparent that modifications and adaptations of those embodiments will occur to those skilled in the art. It is to be expressly understood, however, that such modifications and adaptations are within the scope of the present invention, as set forth in the following claims: | Disclosed is a camouflage material which includes a substantially continuous sheet and has a pattern which extends from the plane of the sheet. The present invention is a unique camouflage system suitable for all camouflage applications, including clothing, covers for blinds and tarps. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of European Patent Application No. 99307835.1, which was filed on Oct. 5, 1999.
The invention concerns a clock and data recovery circuit and method for clock and data recovery with an improved clock-data alignment. Digital clock aligners (DCA) are used for many applications e.g. whenever data signals are transmitted between different electronic components for clocking a data signal relative to or with a reference clock. Digital clock aligners are especially necessary for data transfer within and between computer networks, but also within electronic devices when a data signal is transferred between different components or locations. Due to the ever increasing demand for an improved data transfer the requirements for a clock-data alignment are increasing correspondingly. Today, typical data transfer rates are in the range of hundreds to thousands of Megabits per second causing only less than a few nanoseconds per transferred bit.
However, very often each data processing component has it's own operating frequency, typically defined by a reference clock and in many cases of data transmission by a local reference clock. With this reference clock e.g. processors and/or memory or other data handling components are clocked. When data are transferred from a transmitting component to a receiving component the clocking of both components must be synchronous or quasi synchronous for a proper handling of the data in the receiving component, e.g. for sorting in an associated register. Even if two components are intend to operate at the same frequency the internal clocks frequently are not precise enough to guarantee synchronization over a long term period. Therefore, the data signal is usually synchronized with a reference clock and both data signal and clock signal are transmitted to the receiving component.
A typical digital clock aligner is distributed by Lucent Technologies and described in the product description 1243A “156 Mbit/s One Channel Digital Timing Recovery”. Such prior art digital timing recovery unit aligns an input data signal to a local reference clock and outputs a retimed data and a recovered clock signal. Moreover, the output data is phase-aligned with the output clock. This digital clock aligner uses a 156 MHz reference clock and divides a clock cycle into 32 phases. The rising and falling edge of a single clock phase is used to trigger the data sampling for aligning the data signal to the clock. The signal is sampled by a phase detector, which includes a truth table yielding a binary output value providing for the regular commands up and down which are transferred to a counter connected to the phase detector. The truth table also contains “no action” as possible result, but this is however, not a regular output once the data signal and the clock are locked in desired position, but is only the output of an error state when the alignment of the data signal and the clock is deteriorated. Once the data signal is locked to the reference clock the counter necessarily jumps up or down, typically, it jumps alternately up and down when the alignment is centered around the desired position.
Such a prior art device for clock/data recovery is disadvantageous in certain regards, as the recovered clock and the aligned data signal are permanently jittering due to the jumps up and down causing an data signal having a reduced temporal or phase related accuracy. Therefore, also components receiving the recovered clock and the aligned data signal often have own digital clock aligners and, typically, at least additional data buffers as the transferred signals have to be improved in temporal and/or phase related accuracy which causes additional costs and extended circuitry.
An object of the invention is therefore, to provide a clock and data recovery circuit with an improved alignment between the data and the clock signals reducing disadvantages of the prior art digital clock aligner.
The object of the invention is achieved by a clock and data recovery circuit according to claim 1 and a method for clock and data recovery according to claim 13 yielding a surprisingly stable alignment of the data and the clock signals.
SUMMARY OF THE INVENTION
The clock and data recovery circuit comprises a data input for receiving a data signal and a reference clock signal which reference clock signal also simplified only is called a “reference clock” and is defining a timing signal for strobing the data signal. The clock and data recovery circuit further comprises a phase generator which divides a clock cycle into N phases. The number N is preferably a power of two e.g. N=32 and the clock and data recovery circuit further comprises a data sampling component which having a buffer component and a phase detector. The received data signal is buffered by the buffer component for sampling the data signal. The data signal states sampled cause a logic output statement of the data sampling component based on a truth table. The clock and data recovery circuit further comprises a counter assigned to the phase detector processing the output statement of the data sampling component. The clock and data recovery circuit further comprises a phase selector assigned to the counter selecting three or more clock phases, wherein theses clock phases are triggering the data sampling preferably by switching the buffer component.
The output statement of the phase detector preferably causes a counting up, counting down or holding of the counter. Especially the holding of the counter, when the data signal is in a locked desired position, is advantageous because the jitter of the output data signal and a recovered clock signal is drastically reduced.
The data signal is preferably a binary signal defining a bit sequence comprising the state zero and one, since binary signals are of major interest for fast data transmission.
In a preferred embodiment of the clock and data recovery circuit the buffer component comprise a bistable multivibrator or preferably consists of a number of bistable multivibrators, as bistable multivibrators are simple and cheap triggerable digital buffers. A preferred example of a bistable multivibrator has a data input, a data output and a trigger input.
In a further preferred embodiment the buffer component comprises or is preferably partitioned in three groups of bistable multivibrators each group preferably being triggered by one of the three clock phases respectively, when only three clock phases are used. It shall be understood that it might be further advantageous to use more than three clock phases to improve the stability of the data alignment. The bistable multivibrators are preferably switching and therefore buffering the data signal when triggered by the clock phase at the trigger input.
In a further preferred embodiment, the three clock phases i, j and k depend on each other as:
J=i+N/ 2 −M and k=i+N/ 2 +M if i:≦N/ 2
and
j=i−N/ 2 −M and k=i−N/ 2 +M if i>N/ 2
with a parameter M selectable within 0<M<N/2.
This choice of the three clock phases is advantageous as the clock phase j and k are symmetrically distributed around i+N/2 or i−N/2. The parameter M defines the distance between the clock phase j and k.
In a further preferred embodiment, the retimed data signal is transmitted from the buffer portion to an output of the clock and data recovery circuit, wherein the retimed data signal is triggered by the clock phase i. This is advantageous as in the desired locked position the clock phase i is near the center of a data bit, i.e. providing for a good alignment of the data signal and the clock signal.
Furthermore, it is advantageous to detect the buffered data signal switched to the data outputs of the three buffer portions by the phase detector. It is advantageous to further detect the data signal state of a previous cycle of the timing signal, preferably at the previous clock phase i. The resulting four sampled data signal states can be further processed e.g. looked up in a predefined truth table.
In a further preferred embodiment the clock and data recovery circuitry comprises a low pass filter assigned to the phases detector for preferably filtering the output statement of the phases detector.
Moreover, it is advantageous to use dual rail amplifiers at the data input and/or the data output and/or the recovered clock signal output. The dual rail amplifiers are preferably operating according to the low voltage differential swing (LVDS) standard and advantageously suppress common mode interference signals.
The clock and data recovery circuit and the method for clock and data recovery according to the invention can be used for many applications, e.g. for synchronous optical network (SONET), synchronous digital hierarchic networks (SDH), networks operated in the synchronous transfer mode (ATM), local area networks (LAN) or plesiochronous digital hierarchic networks (PDH). Due to the stability of the retimed output data signal and the recovered timing signal it is even possible to receive these signals and directly process them without retiming them in a receiving component.
The invention is described in detail hereinafter by means of preferred embodiments and reference is made to the attached detailed drawings where necessary.
BRIEF DESCRIPTION OF THE FIGURES
It is shown in
FIG. 1 : a block diagram of a preferred embodiment of the clock and data recovery circuit according to the;
FIGS. 2 a–f : six examples of the phase alignment of clock phases and a data signal as appearing in the embodiment of FIG. 1 ;
FIG. 3 a : a circle diagram of an exemplary chosen set of clock phases; and
FIG. 3 b : the relative alignment of the clock phases of FIG. 3 a.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a clock and data recovery circuit 1 with a first data input including a positive data input 2 a and an inverted data input 2 b operating preferably according to the well known low voltage differential swing standard (LVDS) and also shows a first dual rail input amplifier 3 . In the preferred embodiment the input data signal has a data rate of about 155.52 Mbit/s. The amplifier 3 is connected to a first buffer portion comprising a first, a second and a third bistable multivibrator 11 , 12 , 13 . The amplifier 3 is further connected to a second buffer portion comprising a fourth and fifth bistable multivibrator 21 , 22 and is connected to a third buffer portion on comprising a sixth and seventh bistable multivibrator 31 , 32 . Each bistable multivibrator has a data input “D”, a data output “Q” and a trigger input “>”. Those skilled in the art will recognize each buffer portion also as a first-in-first-out (FIFO) register. The data output of the third bistable multivibrator 13 is connected to a second dual rail amplifier 43 which amplifies the data signal for transmitting having a positive data output 42 a and an inverted data output 42 b , e.g. in LVDS-standard.
A phase detector 50 comprises a first, a second, a third and a fourth input 50 a , 50 b , 50 c , 50 d to which the output of the first bistable multivibrator 11 , the output of the fifth bistable multivibrator 22 , the output of the seventh bistable multivibrator 32 and the output of the second bistable multivibrator 12 are connected, respectively. The output 50 e , 50 f of the phase detector 50 is connected to the input 51 a , 51 b of a four bit up/down counter 51 which serves as a low pass filter. The output 51 c , 51 d of the up/down counter 51 is connected with the input 52 a , 52 b of a five bit up/down counter 52 . The output 52 c of the counter 52 is connected to the first input 53 a of a phase clock selector (or phase selector) 53 .
A reference clock signal, e.g. in LVDS standard, having a positive and an inverted signal input 54 a , 54 b is amplified by a dual rail amplifier 55 which is connected via a component 56 to a phase/frequency detector 57 which is connected to a loop filter 58 .
The loop filter 58 is connected to a 156 MHz voltage controlled oscillator (VCO) 59 which is connected via a multiplexer 60 to a second input 53 b of the phase clock selector 53 . Those skilled in the art will understand that the elements 55 – 60 form a phase locked loop (PLL) component.
Outputs 53 c , 53 d , 53 e of the phase clock selector 53 are connected to inputs 61 a , 61 b , 61 c of a PLL bypass 61 , respectively, said PLL bypass 61 having a first, a second and a third output 61 d , 61 e , 61 f . The first output 61 d is connected to the trigger inputs of the first, the second, the third, the fifth and the seventh bistable multivibrators 11 , 12 , 13 , 22 , 32 and to a dual rail amplifier 44 . The dual rail amplifier 44 transmits the recovered clock signal of the phase clock selector 53 having a positive and an inverted signal output 44 a , 44 b . The second output 61 e of the PLL bypass 61 is connected to the trigger input of the fourth bistable multivibrator 21 . The third output 61 f of the PLL bypass 61 is connected to the trigger input of the sixth bistable multivibrator 31 .
The PLL component 55 – 60 creates a 156 MHz timing signal divided into a number of N phases. The number N is preferably a power of two and is in this preferred embodiment N=32. The phase clock selector comprises three multiplexers (not shown) selecting three clock phases i, j and k of the 32 phases.
A data signal received by the data input and amplified by the amplifier 3 is put on the inputs D of the bistable multivibrators 11 , 21 , 31 . When the phase clock selector 53 serves the clock phase i via the PLL bypass 61 to the trigger inputs of the bistable multivibrator 11 the actual state of the data signal (0 or 1) is switched to the data output Q anc is buffered therewith. In other words the data signal is strobed at the time of the clock phase i and the strobed state of the data signal called D−1 (or in a more precise notation D i-1 ,) is buffered. When the clock phase j is served to the trigger input of the fourth bistable multivibrator 21 the data signal is strobed again and the bistable multivibrator 21 buffers the data signal state D j at it's output Q. When the clock phase k is served to the trigger input of the sixth bistable multivibrator 31 the data signal is strobed again and the bistable multivibrator 31 buffers the data signal state D k at it's output Q. When the next clock phase i is served with the following clock cycle the data signal states, D−1, D j , D k are switched through the second, the fifth and the seventh bistable multivibrator 12 , 22 , 32 , respectively and are buffered therewith at the respective outputs Q. Also the data signal at the input D of the first bistable multivibrator 11 is strobed again by the clock phase i and the next signal state called D i is buffered by the first bistable multivibrator 11 at it's output Q. Now the states D i , D j , D k and D−1 are buffered and are sitting at the inputs 50 a , 50 b , 50 c , 50 d of the phase detector 50 , respectively, and can be read out by the phase detector 50 . Preferably, the phase detector 50 is also strobed by the clock phase i, especially by a delayed clock phase i.
The phase detector reads a four digit binary number resulting from the four digital states D−1, D i , D j and D k and creates an output statement based on the following truth table (table 1).
TABLE 1
Number
D-1
D i
D j
D k
C u
C d
1
0
0
0
0
0
0
2
0
0
0
1
0
0
3
0
0
1
0
0
0
4
0
0
1
1
0
0
5
0
1
0
0
1
0
6
0
1
0
1
0
0
7
0
1
1
0
0
0
8
0
1
1
1
0
1
9
1
0
0
0
0
1
10
1
0
0
1
0
0
11
1
0
1
0
0
0
12
1
0
1
1
1
0
13
1
1
0
0
0
0
14
1
1
0
1
0
0
15
1
1
1
0
0
0
16
1
1
1
1
0
0
D i , D j and D k are the states of the data signal at the clock phases i, j and k, respectively. D−1 is the state of the bit previous to the bit of state D i . C u and C D are counter up and counter down output statements respectively. (C u , C D )=(1, 0) means a counting up, (C u , C D )=(0, 1) means a counting down and (C u , C D )=(0, 0) means a holding of the counter. The table values-number 7 and 10, causing a holding of the counter are error states that should not occur when the clock and data recovery is in a stable position. The possible output statements counter up, counter down or hold counter are transmitted to the four bit counter 51 for filtering and from there to the five bit counter 52 . The reaction of the five bit counter 52 executing the up, down or hold statement is transmitted to the phase clock selector 53 which is shifting the clock phases i, j and k due to the counter output statement. Clocked by the next clock phase i the data signal buffered at the output Q of the second bistable multivibrator 12 is switched by the third bistable multivibrator 13 to the output amplifier 43 and is aligned to the clock phase i amplified by the dual rail amplifier 44 defining a recovered clock signal. The retimed data signal at the output amplifier 43 is now synchronous to the recovered clock signal at the output amplifier 44 .
FIGS. 2 a–f shows the timing between the clock phases i, j and k indicating arrows and a data signal 74 . Six possible timing situations between the clock phases i, j and k and the data signal are shown. Portions of three data bits 74 a , 74 b , 74 c of the data signal 74 are shown. In FIGS. 2 a–c the state of the first bit (D−1) 74 a is zero, the state of the second bit (D−0) 74 b is one, while in FIGS. 2 d–f the state of the first bit (D−1) 74 a is one and the state of the second bit (D−0) 74 b is zero. In FIGS. 2 a –f the third bit is shown with both possible states zero and one, since the state of the third bit D+1 does not affect the sampling and the synchronization of the bit D−0 visualized in FIGS. 2 a –f, however, the following bit D+1 affects the sampling of bit D+1 in the next recovering cycle.
The state of the data signal is sampled at the clock phases i, j, k and of the bit D−1, preferably by the clock phase i of the previous clock cycle (not shown). The four digit result of the sampling of FIG. 2 a is (D−1, D i , D j , D k )=(0, 1, 0, 1) which causes no counter action looking up in the truth table (table 1). The clock phase i is about in the center of the bit D−0, which is in the desired position near the center of the bit D−0. This desired position is advantageous for later strobing when the data is transmitted by the clock and data recovery circuit. Therefore, the counter is held caused by the result of value number 6 of table 1, which is one of the two desired locked positions (the other one is given by the result of value number 11). Since the frequency of the clock signal is very close to the data rate the desired position can be held for many cycles without changing the counter state.
When the frequency of the clock signal is slightly faster than the data rate the clock phases will drift to the left (to an earlier timing) relative to the data signal. As soon as the data signal state D j at the clock phase j becomes zero shown in FIG. 2 b the four digit value is (D−1, D i , D j , D k )=(0, 1, 0, 0) causing a counting up of the counter looking up the four digit value in the truth table pushing back the clock phases in direction of the desired position. A similar situation as in FIG. 2 b is shown in FIG. 2 c except the clock phases are later than the desired position resulting a four digit value of (D−1, D i , D j , D k )=(0, 1, 1, 1) and causing a counting down of the counter. Thus FIGS. 2 a–c show the oscillation of the clock phases j and k around a rising edge of the data bit therebetween.
Due to the described algorithm the clock and data recovery circuit according to the invention only changes the counter state when necessary resulting in a much more stable synchronization, in advantageous contrast to the cited prior art digital clock aligner. Especially when the data rate and the reference clock frequency are close together, e.g. a clock frequency of 156 MHz and a data rate of 155.52 Mbit/s (as used for the preferred embodiment) the relative drift between the data signal and the clock signal is about 3.1E-3, resulting in a counting up approximately only each 325 th clock cycle and having a stable alignment with held counter for a duration of about 324 clock cycles.
FIGS. 2 d–f show an equivalent situation as shown in FIGS. 2 a–c except that the clock phases j and k are oscillating around a falling edge of the data signal locking the clock phase i near the center of the bit D−0. FIG. 2 d shows the stable position (D−1, D i , D j , D k )=(1, 0, 1, 0) holding the counter (C u , C D )=(0, 0). FIG. 2 e shows the situation where the clock phases are too early (D−1, D i , D j , D k )=(1, 0, 1, J) causing a counting up and FIG. 2 f where the clock phases are too late (D−1, D i , D j , D k )=(1, 0, 0, 0) causing a counting down of the counter.
FIG. 3 a shows a preferred choice of the clock phases i, j and k in a phase circle diagram. It is exemplary chosen N=16 and M=1. i reads i=4, resulting in i+N/2=12 on the opposite side to i in the diagram. j=11 and k=13 are resulting from the chosen M=1 creating a window of two phase intervals therebetween locking the rising or falling edge of a bit as shown in FIGS. 2 a–f . If M is chosen larger than 1 the size of the locking window increases resulting in a longer duration of the stable position holding the counter, but also resulting in a larger range of relative jitter between the clock phase i and the data signal. Without claiming completeness the choice of M can be adapted to the difference of the data rate and the reference clock frequency and/or to the quality of the data signal with M from 1 to N/2−1.
FIG. 3 b shows the relevant timing of the clock phase signals i, i+N/2, j and k 81 , 84 , 82 , 83 of a little more than one clock cycle 85 . The clock cycle 85 goes from a rising edge to the next rising edge or from a falling edge to the next falling edge. The respective bistable multivibrators of FIG. 1 will trigger on the rising edges of the clock phases i, j and k 81 a , 82 b , 83 b . It shall be understood that the invention is not restricted to the preferred embodiments described, but can be realized in many different ways. | The invention concerns a clock and data recovery circuit as well as a method for clock and data recovery using three or more clock phases of a reference clock for locking a data signal and the clock signal yielding a very stable phase alignment of the data and clock signals. In accordance with the invention, two of the clock phases are selected to be 180 degrees out of phase with the third clock phase, plus or minus a parameter M. The data signal is sampled at each of the three or more clock phases and a phase selection signal is generated based on a truth table. The state of the data signal in a previous cycle may further be included in the truth table. | 7 |
REFERENCE TO PRIOR APPLICATIONS
[0001] This application claims priority to U.S. provisional application Ser. No. 61/556,321, filed Nov. 7, 2011; and to French patent application 11 60010, filed Nov. 4, 2011, both incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to new emulsions containing acrylic associative thickening agents which, when polymerized in the presence of particular polyglycerols, have a thickening power which is remarkably stable over time. The viscosimetric variance caused by this type of thickening agent, which appears very rapidly after several days' storage, is notably reduced by this means, in particular in paints with low VOC (Volatile Organic Compound) rates, or paints without VOCs. The user is thus guaranteed identical application properties for their paint, i.e. an unvarying rheological profile for the paint they formulate, and which they apply, independently of the storage time of the paint, over a period which can be as long as several months.
[0003] Additional objects, advantages and other features of the present invention will be set forth in part in the description that follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from the practice of the present invention. The advantages of the present invention may be realized and obtained as particularly pointed out in the appended claims. As will be realized, the present invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the present invention. In this regard, the description herein is to be understood as illustrative in nature, and not as restrictive.
BACKGROUND OF THE INVENTION
[0004] Controlling the rheology of a paint both in the stage of its manufacture, and during its transport, storage or use, remains a priority at the current time. The wide variety of constraints observed in each of these steps relates to a multiplicity of different rheological properties. Nevertheless, it is possible to summarise the requirement of the skilled man in the art in obtaining an effect of the thickening of the paint, both for reasons of stability over time, and for a possible application to a vertical surface, lack of spattering during use, or of sagging after application, etc. As a consequence, the products which contribute to this regulation of the rheological properties have been designated by the term “thickening agents”.
[0005] Historically, since the 1950s cellulose-based gums and products have been used, one of the essential characteristics of which is their high molecular weight.
[0006] However, these compounds have a number of disadvantages, such as their instability over time (see document U.S. Pat. No. 4,673,518), the need to use a large quantity of them (see document EP 0 250 943 A1), and their production costs, notably in terms of waste treatment (see document U.S. Pat. No. 4,384,096).
[0007] Thickening agents called “associative” thickening agents were then created: these are water-soluble polymers having insoluble hydrophobic groups. Such macromolecules have an associating character: when introduced into water, the hydrophobic groups tend to assemble in the form of micellar aggregates. These aggregates are linked together by the hydrophilic parts of the polymers: a three-dimensional network is then formed which causes the viscosity of the medium to be increased. The operating mechanism and their characteristics are now well known and described, for example in the documents “Rheology modifiers for water-borne paints” (Surface Coatings Australia, 1985, pp. 6-10) and “Rheological modifiers for water-based paints: the most flexible tools for your formulations” (Eurocoat 97, UATCM, vol. 1, pp 423-442).
[0008] Among these associative thickening agents, a technological platform is known which contains particular emulsions known as “HASE” (Hydrophobically modified Alkali-Soluble Emulsions). These contain polymers of (meth) acrylic acid, of an ester of these acids and of an associative monomer consisting of an oxyalkylated chain terminated by a hydrophobic group.
[0009] In the case of these associative monomers, the choice of hydrophobic group determines the varied rheological properties. The following patent applications filed by Coatex™ may be cited with this regard: EP 0 577 526 A1, which describes a fatty chain with linear or branched units of the alkyl and/or aryl type, having 26 to 30 carbon atoms, to develop high viscosities under a low shearing gradient, and EP 1 778 797 A1, which describes a branched terminal chain comprising 10 to 24 carbon atoms, to improve the pigmentary compatibility, and increase the viscosity generally.
[0010] However, associative thickening agents—and notably HASE—have a tendency to cause viscosities which may increase over the storage time, from the time when they are introduced into a paint. It is, indeed, well known that the thickening power which they develop tends to increase over time, when they are associated in the paint with binders which require no or little in the way of coalescence aid agents: this trend can generally be observed 8 days after formulation. Such variance is not desirable, since it is synonymous with a loss of control of the paint's rheological profile.
SUMMARY
[0011] The inventors have now developed a new method for manufacturing aqueous emulsions containing HASE-type thickening agents, involving the use of particular polyglycerols. The resulting products develop viscosities which are completely stable within the paint formulations in which they are incorporated: a simple and effective solution is therefore found to the problem of rheological variance as mentioned above.
[0012] One of the characteristics of the polyglycerols in question, in addition to their chemical nature, is based on the fact that they are used during the synthesis of HASE-type thickening agents: in this sense, these are “polymerization surfactants”. Conversely, “formulation surfactants” are used after the polymerization of the thickening agents, notably in order to use the finished product obtained after polymerization in water.
[0013] The use of surfactants during polymerization of an acrylic associative thickening agent is already known: it is notably described in document WO 2009 019225 A1. Furthermore, it is already known to use glycerol during the same type of synthesis, as disclosed in document WO 98 06757 A1. Nevertheless, nothing described or suggested that the use of polyglycerols, as polymerization surfactants, was likely to lead to new aqueous emulsions containing HASE-type associative thickening agents, giving, e.g., the paints into which they are introduced particularly stable viscosities.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] An object of the invention is an aqueous emulsion of an associative thickening agent obtained by polymerization:
a) of at least one monomer which is (meth)acrylic acid, and preferentially methacrylic acid, b) of at least one monomer which is an ester of (meth)acrylic acid, and preferentially ethyl acrylate, c) of at least one monomer having at least one hydrophobic group,
characterised in that d) at least one polyglycerol of formula (I) is used during the polymerization
[0000]
[0000] where R designates hydrogen, an ester group functionalized by an alkyl group, having 8 to 22 carbon atoms, or an alkyl group having 8 to 22 carbon atoms, and preferentially an alkyl group having 8 to 22 carbon atoms.
[0018] This emulsion may also be characterised in that, for the associative thickening agent obtained by polymerization, the polymerization comprises a first step of introducing into water compounds d) and the surfactants other than the compounds d), followed by a second step of increasing the temperature of the medium, followed by a third step of introducing polymerization initiators, and then monomers, possibly added in combination with water and surfactants other than compounds d).
[0019] This emulsion may also be characterised in that, for the associative thickening agent obtained by polymerization, in the polymerization the surfactants other than compounds d) are chosen from among the anionic surfactants, and preferentially from among sodium dodecyl sulphate, dioctyl sodium sulfosuccinate, sodium dodecylbenzenesulfonate, the non-ionic surfactants, and preferentially the ethers of fatty alcohols and of polyoxyethylene glycol, the esters of polyoxyethylene glycol and the blends of these surfactants.
[0020] This emulsion may also be characterised in that, for the associative thickening agent obtained by polymerization, the mass % of surfactants other than d)/polymer is between 1% and 5% in the polymerization.
[0021] This emulsion may also be characterised in that, for the associative thickening agent obtained by polymerization, the polymerization uses, as a % by weight, relative to the total weight of the associative thickening agent:
a) 20% to 60% by weight of at least one monomer which is (meth)acrylic acid, and preferentially methacrylic acid, b) 40% to 80% of at least one monomer which is an ester of (meth)acrylic acid, and preferentially ethyl acrylate, c) 0.5% to 25% of at least one monomer having at least one hydrophobic group, d) 0.1% to 10% by weight of at least one polyglycerol of formula (I),
[0000]
[0000] where R designates hydrogen, an ester group functionalized by an alkyl group, having 8 to 22 carbon atoms, or an alkyl group having 8 to 22 carbon atoms, and preferentially an alkyl group having 8 to 22 carbon atoms.
where the sum of the percentages a), b), c) and d) is equal to 100%.
[0026] This emulsion may also be characterised in that, for the associative thickening agent obtained by polymerization, the monomer containing at least one hydrophobic group has the general formula R—(OE) p -(OP) q —R′, where:
p and q designate integers of less than or equal to 150, at least one of which is non-zero, with preferentially q=0 and 0<p<80, OE and OP designate respectively ethylene oxide and propylene oxide, positioned in a random or regular manner, R designates a polymerisable group, and preferentially the methacrylate or methacrylurethane group, R′ designates a hydrophobic group having at least 6 and at most 36 carbon atoms.
[0031] This emulsion may also be characterised in that, for the associative polymer obtained by polymerization, it has an average molecular mass by weight of between 20,000 g/mol and 1,000,000 g/mol, as measured by GPC.
[0032] Another object of the present invention is the use of any one or more of the emulsions described above, as a thickening agent of an aqueous formulation or an adhesive, where the aqueous formulation is preferentially a water-based paint, a thick film coating, or a filler.
[0033] Another object of the present invention concerns the use of the polyglycerol of formula (I) as a monomer to prepare by polymerization an associative thickening agent in the form of an aqueous emulsion.
[0034] The following examples will enable the present invention to be better apprehended, without however limiting its scope.
EXAMPLES
[0035] In each of the following examples, the molecular masses of the associative thickening agents are determined by GPC.
[0036] Synthesis of the thickening agents is well known to the skilled man in the art, and reference may be made in particular to the various documents cited in the Application as background concerning HASE technology.
[0037] The paints are formulated using the methods well known to the skilled man in the art. All the Brookfield™ viscosities of the paint formulations are determined at 25° C.
Example 1
[0038] This example illustrates the synthesis and use of the various associative thickening agents according to the invention (presence of polyglycerol during the synthesis), or outside the invention (without additives, with glycerol used during the synthesis or as a formulation agent, with polyglycerol added as a formulation surfactant).
[0039] The use in question occurs in a water-based paint formulation, the constitution of which is given in table 1; the figures indicate the mass in grams of each constituent.
[0000]
TABLE 1
Water
294.0
Ammonia 31%
2.0
Ecodis 40 (Coatex ™)
3.0
Acticide MBS (Thor ™)
2.0
Byk ™ 34 (Byk ™)
1.0
TiONA ™ 568 (Cristal ™)
41.0
Durcal 5 (Omya ™)
328.0
Omyacoat ™ 850 OG (Omya ™)
215.0
Axilat ™ DS 910 (Hexion ™)
82.0
Butyl diglycol
20.0
Thickening agent subject to testing
12.0 *
* the value of 12 grams is equal the mass of an emulsion containing 30% by dry weight of polymer (except for test n° 4 which uses 3.0 grams by dry weight of a commercial thickening agent in powder form)
[0040] Test n° 1:
[0041] This test illustrates a HASE thickening agent outside the invention, polymerized with a conventional surfactant.
[0042] This thickening agent results from the synthesis, expressed as a % by weight of the monomers, of:
a) 37.4% of methacrylic acid, b) 54.3% of ethyl acrylate, c) 8.3% of a monomer of formula (I), in which:
where R designates the methacrylate group, q=0, p=25, where R′ designates the hydrophobic group resulting from oxo alcohol having 16 carbon atoms.
[0049] In a 1-litre reactor, 485.4 grams of bipermuted water and 6.66 grams of sodium dodecyl sulphate and 11.5 g of non-ionic surfactant, which is isotridecyl alcohol condensed with 3 molecules of ethylene oxide, are weighed. The base of the tank is then heated to 72° C.±2° C.
[0050] During this time, a pre-emulsion is prepared by weighing the following in a beaker:
149 grams of bipermuted water, 2.33 grams of sodium dodecyl sulphate, 111.33 grams of methacrylic acid; 161.45 grams of ethyl acrylate, 24.6 grams of macromonomer of formula (I).
[0056] The mass of non-ionic surfactant therefore accounts in this case for 3.8% of the total mass of the manufactured polymer.
[0057] 0.95 grams of ammonium persulphate is then weighed, diluted in 10 grams of bipermuted water for the first catalyst, and 0.095 grams of sodium metabisulphite diluted in 10 grams of bipermuted water for the second catalyst. When the base of the tank is at the required temperature, both catalysts are added, and polymerization is effected for 2 hours at 76° C.±2° C., with simultaneous addition of the pre-emulsion. The pump is rinsed with 20 grams of bipermuted water, and is fired for 1 hour at 76° C.±2° C. Finally it is cooled to ambient temperature, and the dispersion obtained in this manner is filtered.
[0058] Test n° 2:
[0059] This test illustrates a HASE thickening agent outside the invention, polymerized with a conventional surfactant.
[0060] This is the same thickening agent as that of test n° 1, in which the non-ionic surfactant has been replaced, in mass terms, by nonylphenol condensed with 4 molecules of ethylene oxide.
[0061] Test n° 3:
[0062] This test illustrates a HASE thickening agent outside the invention, polymerized with a conventional surfactant.
[0063] This is the same thickening agent as that of test n° 1, in which the non-ionic surfactant has been replaced, in mass terms, by a surfactant sold by the company Clariant™ under the name Polyglykol™ B11/150
[0064] Test n° 4:
[0065] This test illustrates a thickening agent outside the invention, formulated in water with the introduction of glycerol after polymerization.
[0066] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1.
[0067] In the final solution with 30% by dry weight of active matter, 3% by dry weight of glycerol from the company Oleon™ relative to the dry weight of polymer is introduced.
[0068] Test n° 5:
[0069] This test illustrates a thickening agent outside the invention, formulated in water with the introduction of polyglycerol after polymerization.
[0070] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1.
[0071] In the final solution with 30% by dry weight of active matter, 3% by dry weight, relative to the dry weight of polymer, of polyglycerol-3 of formula (I), with R═H, and n=3 sold by the company Solvay™, is introduced.
[0072] Test n° 6:
[0073] This test illustrates a thickening agent outside the invention, formulated in water with the introduction of polyglycerol after polymerization.
[0074] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1.
[0075] In the final solution with 30% by dry weight of active matter, 3% by dry weight, relative to the dry weight of polymer, of hydrophobic polyglycerol, which is Chimexane™ NB of formula (I) with R═C 18 H 35 and n=2 sold by the company Chimex™, is introduced.
[0076] Test n° 7:
[0077] This test illustrates a thickening agent outside the invention, polymerized in the presence of glycerol.
[0078] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by glycerol from the company Oleon™.
[0079] Test n° 8:
[0080] This test illustrates a thickening agent according to the invention, polymerized in the presence of polyglycerol-3, which is the one used in test n° 6.
[0081] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by the polyglycerol-3 of test n° 5.
[0082] Test n° 9:
[0083] This test illustrates a thickening agent according to the invention, polymerized in the presence of Chimexane™ NB, which is the one used in test n° 6.
[0084] The thickening agent is that of test n° 1, polymerized according to the technique described in test n° 1, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by the Chimexane™ NB of test n° 6.
[0085] For each of these tests the Brookfield™ viscosities were determined at 25° C., at 10 and 100 revolutions per minute, at instants t=1 day (μ 10 1D , μ 100 1D ) and t=7 days (μ 10 7D , μ 100 7D ), where instant t=0 is the time of manufacture of the paint.
[0086] The results are shown in table 2.
[0000]
TABLE 2
Test n°
1
2
3
4
5
Outside Invention
OI
OI
OI
OI
OI
INvention
μ 10 1D (mPa · s)
6,600
6,500
6,800
5,600
6,200
μ 100 1D (mPa · s)
2,600
2,700
2,800
2,200
2,700
μ 10 7D (mPa · s)
7,500
7,700
7,850
5,900
6,400
μ 100 7D (mPa · s)
3,300
3,450
3,600
2,650
3,100
Δμ 10 (%)
12
16
13
5
3
Δμ 100 (%)
21
22
22
10
13
Test n°
6
7
8
9
Outside Invention
OI
OI
IN
IN
INvention
μ 10 1D (mPa · s)
6,400
9,100
10,500
5,000
μ 100 1D (mPa · s)
2,800
3,600
3,800
2,100
μ 10 7D (mPa · s)
6,750
10,600
10,800
5,050
μ 100 7D (mPa · s)
3,150
4,900
3,900
2,100
Δμ 10 (%)
5
14
3
1
Δμ 100 (%)
13
27
3
0
[0087] These results demonstrate that only the thickening agents polymerized in the presence of a polyglycerol according to the invention enable the changes of viscosity of the paint after 7 days to be limited. With test n° 9, which represents the preferential variant of the invention, it is even possible to stabilise the paint's viscosity almost perfectly one week after its manufacture.
[0088] For the latter test, the Brookfield™ viscosity measurements at 10 and 100 revolutions per minute were repeated after 2 months: a variation of the viscosities of less than 3% of the initially measured values was observed, denoting excellent stability over time.
Example 2
[0089] This example illustrates the synthesis and use of different associative thickening agents, according to the invention (presence of polyglycerol during the synthesis), or outside the invention (without addition of polyglycerol during the synthesis).
[0090] The use in question occurs in a water-based paint formulation, the constitution of which is given in table 3; the figures indicate the mass in grams of each constituent.
[0000]
TABLE 3
Water
281.0
Ammonia 31%
2.0
Ecodis 40 (Coatex ™)
3.0
Acticide MBS (Thor ™)
2.0
Byk ™ 34 (Byk ™)
1.0
TiONA ™ 568 (Cristal ™)
41.0
Durcal 5 (Omya ™)
328.0
Omyacoat ™ 850 OG (Omya ™)
215.0
Axilat ™ DS 910 (Hexion ™)
82.0
Butyl diglycol
20.0
Thickening agent subject to testing
24.0 *
* the 24 grams are the mass of an emulsion containing 30% by dry weight of polymer
[0091] Test n° 10:
[0092] This test illustrates a HASE thickening agent outside the invention, polymerized with a conventional surfactant.
[0093] This thickening agent results from the synthesis, expressed as a % by weight of the monomers, of:
a) 33.7% of methacrylic acid, b) 59.4% of ethyl acrylate, c) 6.9% of a monomer of formula (I), in which:
R designates the methacrylate group q=0, p=25, R′ designates the branched hydrophobic group with 16 carbon atoms.
[0100] In a 1-litre reactor, 288 grams of bipermuted water, 3.5 grams of sodium dodecyl sulphate and 11.5 g of non-ionic surfactant, which is isotridecyl alcohol condensed with 3 molecules of ethylene oxide, are weighed. The base of the tank is then heated to 72° C.±2° C.
[0101] During this time, a pre-emulsion is prepared by weighing the following in a beaker:
285 grams of bipermuted water, 3.5 grams of sodium dodecyl sulphate, 102.06 grams of methacrylic acid; 180 grams of ethyl acrylate, 21 grams of macromonomer of formula (I), 0.64 g of dodecylmercaptan.
[0108] The mass of non-ionic surfactant therefore accounts in this case for 3.6% of the total mass of the manufactured polymer.
[0109] 0.95 grams of ammonium persulphate is then weighed, diluted in 10 grams of bipermuted water for the first catalyst, and 0.095 grams of sodium metabisulphite diluted in 10 grams of bipermuted water for the second catalyst. When the base of the tank is at the required temperature both catalysts are added and polymerization is effected for 2 hours at 76° C.±2° C., with simultaneous addition of the pre-emulsion. The pump is rinsed with 20 grams of bipermuted water, and is fired for 1 hour at 76° C.±2° C. Finally it is cooled to ambient temperature, and the dispersion obtained in this manner is filtered.
[0110] Test n° 11:
[0111] This test illustrates a thickening agent according to the invention, polymerized in the presence of polyglycerol-3 sold by the company Solvay™
[0112] The thickening agent is that of test n° 10, polymerized according to the technique described in test n° 10, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by the polyglycerol-3 of test n° 5.
[0113] Test n° 12:
[0114] This test illustrates a thickening agent according to the invention, polymerized in the presence of Chimexane™ NB.
[0115] The thickening agent is that of test n° 10, polymerized according to the technique described in test n° 10, except that the polymerization surfactant has been substituted, in mass terms, by the Chimexane™ NB.
[0116] Test n° 13:
[0117] This test illustrates a HASE thickening agent outside the invention, polymerized with a conventional surfactant.
[0118] This thickening agent results from the synthesis, expressed as a % by weight of the monomers, of:
a) 35.57% of methacrylic acid, b) 52.43% of ethyl acrylate, c) 12% of a monomer of formula (I), in which:
R designates the methacrylate group, q=0, p=30, R′ designates the hydrophobic group consisting of 12 carbon atoms and derived from ethoxylation of an oxo alcohol consisting of 12 carbon atoms.
[0125] In a 1-litre reactor 485.4 grams of bipermuted water and 6.66 grams of sodium dodecyl sulphate and 11.5 g of a surfactant sold by the company Clariant™ under the name Polyglykol™ B11/150 are weighed. The base of the tank is then heated to 72° C.±2° C.
[0126] During this time, a pre-emulsion is prepared by weighing the following in a beaker:
[0127] 149 grams of bipermuted water,
0.33 grams of sodium dodecyl sulphate, 105.8 grams of methacrylic acid; 155.9 grams of ethyl acrylate, 35.7 grams of macromonomer of formula (I).
[0132] The mass of surfactant therefore accounts in this case for 3.87% of the total mass of the manufactured polymer.
[0133] 0.95 grams of ammonium persulphate is then weighed, diluted in 10 grams of bipermuted water for the first catalyst, and 0.095 grams of sodium metabisulphite diluted in 10 grams of bipermuted water for the second catalyst. When the base of the tank is at the required temperature both catalysts are added, and polymerization is effected for 2 hours at 76° C.±2° C., with simultaneous addition of the pre-emulsion. The pump is rinsed with 20 grams of bipermuted water, and is fired for 1 hour at 76° C.±2° C. Finally it is cooled to ambient temperature, and the polymer obtained in this manner is filtered.
[0134] Test n° 14:
[0135] This test illustrates a thickening agent according to the invention, polymerized in the presence of polyglycerol-4 of the company Solvay™
[0136] The thickening agent is that of test n° 13, polymerized according to the technique described in test n° 13, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by polyglycerol-4.
[0137] Test n° 15:
[0138] This test illustrates a thickening agent according to the invention, polymerized in the presence of Chimexane™ NB sold by the company Chimex™
[0139] The thickening agent is that of test n° 13, polymerized according to the technique described in test n° 13, except that the non-ionic polymerization surfactant has been substituted, in mass terms, by the Chimexane™ NB.
[0140] For each of these tests the Brookfield™ viscosities were determined at 25° C., at 10 and 100 revolutions per minute, at instants t=1 day (μ 10 1D , μ 100 1D ) and t=7 days (μ 10 7D , μ 100 7D ), where instant t=0 is the time of manufacture of the paint.
[0141] The results are shown in table 4.
[0000]
TABLE 4
Test n°
10
11
12
Outside Invention
OI
IN
IN
INvention
μ 10 1D (mPa · s)
7,700
8,500
8,200
μ 100 1D (mPa · s)
2,700
2,900
3,000
μ 10 7D (mPa · s)
8,100
8,600
8,300
μ 100 7D (mPa · s)
3,100
3,000
3,000
Δμ 10 (%)
5
1
1
Δμ 100 (%)
15
3
0
Test n°
13
14
15
Outside Invention
OI
IN
IN
INvention
μ 10 1D (mPa · s)
7,300
7,000
7,100
μ 100 1D (mPa · s)
3,000
2,400
2,500
μ 10 7D (mPa · s)
8,700
7,500
7,600
μ 100 7D (mPa · s)
3,300
2,500
2,600
Δμ 10 (%)
19
7
7
Δμ 100 (%)
10
4
4
[0142] These results demonstrate that only the thickening agents polymerized in the presence of polyglycerols according to the invention enable the changes of viscosity of the paint after 7 days to be limited, and the best results are always obtained with the preferred variant of the invention.
[0143] The excellent result obtained with test n° 12 may be noted. For the latter test, the Brookfield™ viscosity measurements at 10 and 100 revolutions per minute were repeated after 1 month: a variation of viscosities of less than 5% of the initially measured values is observed.
[0144] As used herein the term (meth)acrylic means methacrylic and acrylic, and supports both terms. As used herein the terms composed of, contains, containing, and terms similar thereto, when referring to the ingredients, parts, reactants, etc., of a composition, component, etc., mean, in their broadest sense, “includes at least” (i.e., comprises) but also include within their definition all those gradually restricted meanings until and including the point where only the enumerated materials are included (e.g., consisting essentially of and consisting of).
[0145] The above written description of the invention provides a manner and process of making and using it such that any person skilled in this art is enabled to make and use the same, this enablement being provided in particular for the subject matter of the appended claims, which make up a part of the original description. As used herein, the phrases “selected from the group consisting of,” “chosen from,” and the like include mixtures of the specified materials. The term “mentioned” notes exemplary embodiments, and is not limiting to certain species. As used herein the words “a” and “an” and the like carry the meaning of “one or more.”
[0146] Preferred embodiments herein, fully described and enabled, include:
1. An aqueous emulsion of an associative thickening agent comprising water and an associative thickening agent obtained by polymerization: a) of at least one monomer which is (meth)acrylic acid, b) of at least one monomer which is an ester of (meth)acrylic acid, c) of at least one monomer having at least one hydrophobic group,
in the presence of d) at least one polyglycerol of formula (I):
[0000]
[0000] where R designates hydrogen, an ester group functionalized by an alkyl group, having 8 to 22 carbon atoms, or an alkyl group having 8 to 22 carbon atoms.
2. An emulsion according to embodiment 1, wherein the associative thickening agent is obtained by introducing into water compound(s) d) and any surfactant(s) other than the compound(s) d), followed by increasing the temperature of the medium, followed by introducing a polymerization initiator, and then monomers a), b) and c), the monomers optionally being added in combination with water and any surfactant(s) other than compound(s) d). 3. An emulsion according to embodiment 2, wherein surfactant(s) other than compound(s) d) are used, and are chosen from anionic surfactants. 4. An emulsion according to one of the embodiments 3, wherein the mass % of surfactant(s) other than d)/polymer is between 1% and 5% in the polymerization. 5. An emulsion according to embodiment 1, wherein the associative thickening agent is obtained by polymerizing, as a % by weight, relative to the total weight of the associative thickening agent: a) 20% to 60% by weight of at least one monomer which is (meth)acrylic acid, b) 40% to 80% of at least one monomer which is an ester of (meth)acrylic acid, and c) 0.5% to 25% of at least one monomer having at least one hydrophobic group, in the presence of d) 0.1% to 10% by weight of at least one polyglycerol of formula (I)
where the sum of the percentages a), b), c) and d) is equal to 100%.
6. An emulsion according to embodiment 1, wherein the hydrophobic group of the monomer containing at least one hydrophobic group has at least 6 and at most 36 carbon atoms. 7. An emulsion according to embodiment 1, wherein the monomer containing at least one hydrophobic group has the general formula R—(OE) p -(OP) q —R′, where: p and q designate integers of less than or equal to 150, at least one of which is non-zero, OE and OP designate respectively ethylene oxide and propylene oxide, R designates a polymerisable group, R′ designates a hydrophobic group having at least 6 and at most 36 carbon atoms. 8. An emulsion according to embodiment 1, wherein the associative thickening agent has an average molecular mass by weight of between 20,000 g/mol and 1,000,000 g/mol, as measured by GPC. 9. An emulsion according to embodiment 1, wherein a) is methacrylic acid and b) is ethyl acrylate. 10. An emulsion according to embodiment 3, wherein the anionic surfactants are selected from among sodium dodecyl sulphate, dioctyl sodium sulfosuccinate, sodium dodecylbenzenesulfonate, and mixtures thereof. 11. An emulsion according to embodiment 2, wherein surfactant(s) other than compound(s) d) are used, and are chosen from non-ionic surfactants. 12. An emulsion according to embodiment 11, wherein the non-ionic surfactants are selected from ethers of fatty alcohols and of polyoxyethylene glycol, esters of polyoxyethylene glycol, and mixtures thereof. 13. An emulsion according to embodiment 7, wherein a) is methacrylic acid and b) is ethyl acrylate. 14. A process, comprising combining the associative thickening agent of embodiment 1 with another material. 15. The process according to embodiment 15, wherein the material is a water-based paint, an adhesive, a thick film coating or a filler. 16. An aqueous formulation comprising the emulsion according to embodiment 1. 17. An aqueous formulation according to embodiment 16, wherein the formulation is an adhesive, a water-based paint, a thick film coating, or a filler. 18. An associative thickening agent obtained by polymerization: a) of at least one monomer which is (meth)acrylic acid, b) of at least one monomer which is an ester of (meth)acrylic acid, and c) of at least one monomer having at least one hydrophobic group,
in the presence of d) at least one polyglycerol of formula (I):
[0000]
[0000] where R designates hydrogen, an ester group functionalized by an alkyl group, having 8 to 22 carbon atoms, or an alkyl group having 8 to 22 carbon atoms.
[0179] All references, patents, applications, tests, standards, documents, publications, brochures, texts, articles, etc. mentioned herein are incorporated herein by reference. Where a numerical limit or range is stated, the endpoints are included. Also, all values and subranges within a numerical limit or range are specifically included as if explicitly written out.
[0180] The above description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, certain embodiments within the invention may not show every benefit of the invention, considered broadly.
[0181] When a polymer is referred to as comprising a monomer, the monomer is present in the polymer in the polymerized form of the monomer. However, for ease of reference the phrase comprising, containing, etc. the (respective) monomer or the like is used as shorthand. | Emulsions containing acrylic associative thickening agents which, when polymerized in the presence of particular polyglycerols, have a thickening power which is remarkably stable over time. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to the manufacture of fibrous, flat-shaped articles and, more particularly, to a process for coagulating aqueous heat-coagulatable polymer binder dispersions impregnated in or coated on such articles.
The term "flat-shaped articles", as used in this application, includes material formed from individual fibers such as, for example, paper, woven fabric, knitted fabric and non-woven fabric. Of these, since non-woven fabrics are the most interesting, with their broad field of use, the invention will be described using the term non-woven fabric. Nonetheless, it should be clear that the inventive process is also applicable to the above-mentioned broader class of fibrous flat-shaped articles.
It is known to make non-woven fabric by forming a non-woven sheet, impregnating the sheet with an aqueous dispersion of a heat-coagulatable polymer binder and to coagulate the dispersion by heating (see U.S. Pat. No. 3,776,799). Known techniques for accomplishing such heating include the use of hot air, heated drums and infrared radiation. However, when a non-woven sheet is heated on both sides by any one of these techniques, water evaporates from both surfaces and the binder migrates toward the evaporation surfaces leaving a space in the middle of the sheet which contains only a very small proportion of binder. Such uneven distribution of the binder in the sheet tends to weaken it and causes it to split or delaminate along the core (i.e., in the area of low binder concentration) when subjected to severe stress. Binder migration upon drying, therefore, presents the man skilled in the art with serious problems.
In order to eliminate these problems, binder dispersions which reduce or eliminate binder migration on exposure to heat have been developed. One known technique to reduce binder migration is to add a thickening agent to the dispersion. Thickening agents, however, are difficult to remove from the sheet after the sheet has been dried and if they remain in the sheet they tend to impair the hand of the finished fabric.
A better known solution to the problem of binder migration is the use of heat sensitizing agents in the dispersion which causes the binder to begin coagulating at such low temperatures that pratically no evaporation takes place before coagulation begins. Depending on the heat sensitizing agents used and the binder system with which they are used, coagulation takes place either by the dispersed binder particles agglomerating to form larger particles which adhere to the fibers in the sheet, or the dispersion, with the binder in it, solidifies into a gel. In either case, by choosing one of these systems and appropriate choice of and proportions of chemical agents, the dispersion can be adjusted to be stable up to a desired temperature below 100°C. and to coagulate suddenly, for example, at between about 30°C. and 80°C. When a non-woven sheet is impregnated with such heat sensitized dispersions and the sheet is subjected to heat, the effect of the heat is to cause sudden coagulation of the binder in the dispersion either by flocculation onto the fibers or by the formation of the dispersion into a gel. In both cases, the location of the binder throughout the fabric in the heating zone is fixed at a temperature below the evaporation temperature of the water so no migration can occur even during subsequent drying of the sheet.
Though these techniques work well in theory, in actual practice, various difficulties have been encountered. Thus, heretofore, for example, after a non-woven sheet has been impregnated either by spraying or dipping, etc., it has in some instances been heated by direct contact with steam heated drums or rolls such as can dryers. While such dryers heat the material sufficiently for coagulation to occur, the binder tends to migrate in a direction away from the drum and the material tends to stick to the dryers, causing surface defects in the sheet.
Infrared heating, while avoiding the surface defect problem of steam heated drums, has several other problems associated with it. The energy density of infrared radiators is low so the area which they cover has to be relatively large. Further, when a continuous web of heat-sensitized aqueous binder dispersion impregnated non-woven material is passed horizontally between infrared radiators and the web breaks, it falls on the lower radiator, presenting a fire hazard. Also, continued processing of the web is delayed while the radiators cool sufficiently to remove it and rethread the apparatus.
Further, it is difficult to adjust the heat output of infrared radiators so that coagulation occurs without unwanted drying. If, on the other hand, a coagulation by flocculation heat-sensitized aqueous binder system is used and the impregnated fabric passes vertically between two infrared radiators, the aqueous residue which is liberated on coagulation of the binder dispersion tends to flow downward in the sheet from the point of coagulation making it impossible to control the dilution of the binder in the non-coagulated portion of the sheet resulting in a finished product having non-uniform properties. The flow of this residue to still uncoagulated portions of the material not only dilutes the binder dispersion in those portions, it also means that more heat energy has to be imparted to that area to achieve coagulation. If this heat is not forthcoming, the material will contain binder in uncoagulated form and migration problems will occur during drying of the sheet at a later stage.
Accordingly, it is the principal object of this invention to provide a method which avoids the disadvantages of known prior art techniques and in which binder migration is prevented in a simple, economic manner.
SUMMARY OF THE INVENTION
In a process for manufacturing fibrous flat-shaped articles such as paper, knitted fabric, woven fabric and non-woven fabric which have been coated or impregnated with a dispersion of a polymeric binder including a sensitizing agent for causing the dispersion to coagulate at a temperature substantially below 100°C of the invention comprises the step of impinging live steam on the treated material to suddenly heat the dispersion in the material causing it to coagulate. This steam impinging step includes directing at least one jet of steam at a pressure higher than atmospheric pressure against at least one major surface of the article. Where the material is a non-woven, it is preferably impregnated with a heat-sensitized, aqueous, colloidal dispersion of a polymeric binder having a coagulation temperature of between about 30°C. to about 80°C. The preferred process according to the invention also includes the step of removing at least a portion of the aqueous residue from the material after coagulation by a non-evaporative technique such as squeezing the material following its exposure to live steam. Thereafter, if desired, the material may be washed to remove further portions of this residue. The preferred process according to the invention additionally includes the step of impinging the steam on the material in a narrowly defined zone. Another preferred aspect of the process according to the invention includes the step of impinging superheated steam on the treated material.
In apparatus for manufacturing fibrous flat-shaped articles which are coated or impregnated with a heat-coagulatable aqueous polymeric binder dispersion coagulatable at temperatures below 100°C. and in which apparatus there are means for coating or impregnating such articles, means for moving them through the apparatus and means for drying them after coagulation, one aspect of the invention includes providing means for impinging live steam on the coated or impregnated article for suddenly coagulating the binder in the article. When used for non-woven materials impregnated with a binder dispersion adapted to adhere the fibers when subjected to heat (rather than one which forms a gel on heating), the apparatus preferably also includes nonevaporative means for removing at least a portion of the aqueous residue from the dispersion after the binder has flocculated and its position in the material has become fixed and before the article is dried. In the preferred embodiment of the apparatus, such means include means for squeezing the material to remove a portion of the residue from it. Means may also be included for washing the non-woven to remove additional portions of the residue.
The apparatus for impinging live steam on articles impregnated with heat sensitized binder systems preferably comprises at least one steam fed pipe adjacent one side of the article. The pipe preferably has a plurality of steam nozzles spaced apart in a line along its length with the nozzles aimed toward the article. The pipe is preferably rotatable about its central axis so the direction of its nozzles can be adjusted. Further, preferably the pipe is movable toward and away from the article to adjust the distance between the nozzles and the article. Where the apparatus is designed for use with non-woven materials, there are preferably two such pipes on opposite sides of the material, both of which are rotatable about their own axes and movable toward and away from the material.
The use of steam as a high energy carrier impinging upon one or more sides of an article coated or impregnated with a heat-coagulatable binder dispersion heats the article quickly accomplishing sudden coagulation of the binder without evaporation and overcomes the other disadvantages of can driers or infrared treating equipment as well. By treating such articles with steam it is possible to transport an article comprising a continuous web of material horizontally between the heating units without any danger of fire, even if the material tears. Further, by simply shutting off the steam, the torn material can rapidly be passed through the narrowly defined steaming zone and rethreaded through the equipment. Because of the high energy density of steam it is not only possible to locate the equipment in a very small amount of space, it also makes possible the faster operation of the apparatus, particularly if the steam used is superheated.
When aqueous binder systems are used which flocculate on being exposed to heat, flocculation on exposure to live steam creates a sudden separation of the water in the dispersion from the binder without evaporation of water taking place in the steaming zone. When infrared heating equipment is used, and particularly if the infrared path is not carefully controlled or overdimensioned, evaporation cannot be prevented. Another advantage of the preferred process according to the invention is that when a flocculating heat-sensitized aqueous binder system is used and the material is subjected to live steam, the water which is separated out from the binder contains a large part of the undesired adjuvants including the heat-sensitizing and emulsion stabilizing aids (i.e., chemical agents) which were present in the dispersion both in dissolved and finely dispersed form. Because this liquid residue is created as a result of the steam treatment rather than from evaporation causing heat, it tends to be diluted (by the steam) rather than thickened and bound more firmly to the fibers as would tend to occur with a heating system in which evaporation occurs.
The step of the preferred process according to the invention in which an article is pressed out or squeezed immediately after coagulation is of particular importance, because this pressing or squeezing not only removes a substantial part of the undesired liquid residue with its dissolved and finally dispersed chemicals from the material, it does this immediately following coagulation so that there is little chance for the residue to be bound to the material by evaporative heating which occurs when the material is dried.
An additional important advantage in the process according to the invention is that the residue which has been squeezed from the sheet material need not be evaporated at all. This in turn results in a considerable savings in the amount of energy required to dry the material, because there is less liquid in it to be dried. Though it is often desirable to wash articles or sheet material after squeezing the liquid residue from them, after the washing step they can again be squeezed in order to remove additional chemicals and water to reduce the amount of energy required for the final drying step.
Any suitable water dispersable binders which are heat sensitizable are suitable in the practice of the invention. There are numerous such materials known to those skilled in the art and the details need not be repeated here. Illustrative well known classes of suitable binders for the process according to the invention include elastic, synthetic or natural polymers which can be coagulated from an aqueous dispersion under the influence of heat. Particularly suitable are: aqueous dispersions of copolymers of butadiene, acrylonitrile and minor amounts of methacrylic acid with free carboxyl groups; copolymers of carboxylated-butadiene-acrylonitrile; butadiene-styrene copolymers modified to include carboxylic groups in the polymer chain; and other polyacrylic and polymethacrylic acid esters and natural or synthetic rubber latex. Some of these products are available under the following trade names from the indicated manufacturers:
"Perbunan-N-Latex 4M", "Perbunan-N 3415 M" and "N Latex T", products of Farbenfabriken Bayer;
"Hycar 2570 x 1" and "Hycar 1570 H 6", products of CIAGO (N. V. Chemische Industrie AKU-Goodrich);
"Primal HA 8", "Primal HA 12" and "Primal HA 16", products of Rohm & Haas;
"Acronal 500 D", a product of BASF (Badische Analine Soda Fabrik); and
"LCG 4412 LATEX", a product of Goodyear Chemical Div. (France).
Any suitable emulsion stabilizers known to be subject to the action of heat sensitizing agents are also suitable in the practice of the invention. There are numerous such materials known to those skilled in the art and the details need not be repeated here. Illustrative well known classes of stabilizers include electrically neutral fatty acid condensation products and alkylaryl polyether alcohols of the octylphenol series, for example, water soluble isooctylphenol-polyethoxy-ethanol containing ten moles of ethylene oxide. The former is available from Bayer under the trade name "Emulvin W". The latter is available from Rohm & Haas under the trade name "Triton X-100".
Further, any suitable heat sensitizing agents known to be useful in making such water dispersable binder dispersions sensitive to the presence of heat are suitable for the practice of this invention. There are numerous such materials known to those skilled in the art. One such class of agents includes functional organopolysiloxanes which are useful for adjusting the coagulation temperature of such binders to between about 30°C. and about 80°C. One such agent is available from Bayer under the trade name "Coagulant WS".
In addition, any suitable agents known to be useful in dispersing the vulcanizing agents in these binder systems are suitable in the practice of the invention. There are numerous such agents known to those skilled in the art so they need not be mentioned here. For example, one well known class of such agents comprise Naphthalenesulfonic acid condensation products. Further, one of these products is available from BASF (Badische Analine Soda Fabrik) under the trade name "Vultamol".
Other features and advantages of the process and apparatus according to the invention will be apparent from the following description taken in connection with the drawing and the amended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagramatic view of the preferred apparatus.
FIG. 2 is a profile view of the steam pipe portions of the apparatus of FIG. 1 shown in profile and illustrating means for adjusting the rotational positions of the pipes as well as for adjusting their distances from the sheet material.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2 of the drawings, the preferred embodiment of the apparatus includes means for impregnating and/or coating a continuous non-woven web of material with a heat coagulatable aqueous dispersion of polymer binder material, means for thereafter heating the material to coagulate the binder, means for thereafter washing the material, means for thereafter drying the material and means for moving the web of non-woven material continuously through each of these means, the central feature of the apparatus being characterized by the fact that the coagulating means comprises at least one pair of steam-fed nozzle pipes extending across the direction of travel of the web with its nozzles aimed towards the web. The pipes preferably lie on opposite sides of the web a predetermined adjustable distance away from its major surfaces. Also, there are means for adjusting this distance as well as means for adjusting the rotational position of each pipe about its central axis.
Discussing the process and the preferred embodiment of the apparatus together in somewhat more detail, a web of non-woven fabric 1 is drawn continuously from a supply (not shown) over guide rolls 3 through a tank 4 filled with a heat-sensitized aqueous colloidal dispersion of polymeric binder material 5. The purpose of the tank is to coat or impregnate the article or fabric with the binder dispersion. In the examples set forth below, the fabric web 1 traveled at a linear velocity of from between about 4 to about 20 meters per minute.
Driven squeeze rolls 6 at the discharge end of the tank 4 provide a pulling force on the fabric web 1 for drawing the fabric from the supply. They also reduce the aqueous dispersion content of the web to a desired proportion of the dry fabric weight. The fabric emerges from between these rolls uniformly treated with the binder dispersion. Next, the web passes horizontally between two steam fed nozzle pipes 7, which extend above and below and completely across the path of the traveling web. A row of perforations 8, longitudinally spaced about 1 centimeter apart in each pipe, extends across the width of the fabric. These perforations have a diameter of between about 1-2 millimeters and are directed toward the opposite sides (i.e., the major surfaces) of the fabric web. As illustrated, the pipes are rotatable about their own axes by a linkage system (See FIG. 2).
Since this system is the same for each pipe it will be explained referring to one pipe only. The linkage includes gear wheel 16 mounted concentrically to one end of pipe 7, a pinion gear 18 engaged with the gear wheel 18, a shaft 20 on one end of which the pinion 18 is mounted, a bearing 22 for carrying the shaft 20 and a handle 24 which is removably splined to the end of the shaft opposite the pinion 18. Because the handle 24 is removable it can be mounted on either of the shafts 24. When used to rotate the shaft it adjusts the rotational position of the pipe with which it is associated. Other linkage systems for accomplishing this rotational adjustment may also be used.
Further, any suitable means for adjusting the distances of the two pipes apart from each other may also be used. One such system illustrated in FIG. 2 includes a plurality of threaded collars 26 carrying one end of the pipes 7 and the bearings 22 at the other end of the pipes on a pair of threaded shafts 28 adjacent opposite ends of both pipes. These shafts 28 are mounted vertically in plane of the pipes and lie perpendicularly to them. They are rotatably mounted in supports 29 at their opposite ends and are rotatably drivable by a pair of cranks 30 connected to them. The threads on similar halves of shafts 28 are formed in one direction, but the threads on one half are formed in the opposite direction from those on the other half. Accordingly, when the cranks 30 are rotated in the same direction, the pipes 7 are carried further apart or moved closer together by the collars 26 depending on the direction in which the cranks are rotated.
The pipes 7 are connected to a steam boiler (not shown) through a superheater 9 so that jets of steam 10 are discharged from the pipes against the major faces of fabric web 1. The steam impinges on about 20 linear centimeters of fabric web when the pipes 7 are spaced about 15 centimeters apart and the steam is directed perpendicularly against the fabric web. This gives a heating zone about 20 centimeters long. In the examples set forth hereinafter, the steam in pipes 7 was at a temperature of about 130°C. and at a pressure of about 7.5 p.s.i.g. with a fabric web linear velocity of about 4 meters per minute and about 3 centimeters spacing between pipes 7, the temperature in the web was about 70°C. It has been found from the examples set forth hereinafter, that a period of steaming or contact of steam with the web of up to about 3 seconds is sufficient to cause coagulation of the dispersion.
When performations 8 are aligned in a common vertical plane, as shown in the drawing, directing the steam perpendicularly against the fabric web 1, the length of the heating zone is minimized. Rotation of pipes 7 effects fine adjustment of the distance travelled by the steam, and therefore its temperature, before it impinges on the fabric web and also permits fine adjustment of the length of the heating zone. Additional adjustment of these variables is effected by adjusting the vertical spacing between pipes 7. Preferably this distance is adjustable to leave a distance of from about 1 centimeter to about 15 centimeters between them.
Another pair of driven squeeze rolls 11 pulls the fabric web 1 through the heating zone and squeezes out much of the aqueous residue formed during coagulation. In the preferred embodiment, the squeeze rolls 11 comprise one rubber roll (Shore A hardness 70) and one steel roll.
The fabric web 1 next passes through a wash tank 12 containing a conventional suction cylinder 13 (preferably having a diameter of about 50 centimeters). The dashed line above tank 12 indicates that this washing apparatus may be bypassed if desired.
A third pair of driven squeeze rolls 14 pulls the fabric web 1 through the wash tank 12 and squeezes out more of the residue and much of the wash water picked up in the tank 12. The fabric web 1 next is dried in an oven 15 in a manner conventional in itself and, therefore, not shown or described in detail.
The following examples are further illustrative of the process according to this invention. All percentage values are by weight unless otherwise stated.
EXAMPLE 1
A heat coagulatable aqueous colloidal dispersion of polymeric elastomeric binder was prepared from the ingredients and in the ratio of amounts set forth in the following table:
Ingredient Solids weight Solids % Total weight__________________________________________________________________________An aqueous dispersion ofa vulcanizable copolymerof butadiene, acrylonitile 100 kg 45 % 222 kgand 4 % methacrylic acid(Perbunan-N-Latex 4M)An electrically neutralfatty acid condensation 6 kg 20 % 30 kgproduct (Emulvin W)A functional organopoly-siloxane coagulant 4,5 kg 33 % 13,6 kg(Coagulant WS)Colloidal sulfur 1,2 kgZinc oxide 6,0 kg2-mercaptobenzothiazole 30 % 29,7 kgzinc salt 0,6 kgZinc diethyldithiocarbamate 0,4 kgA naphthalenesulfonic acidcondensation product 0,8 kg(Vultamol)Water -- -- 103,4 kg 119,5 kg 398,7 kgTotal solids % about 30 %__________________________________________________________________________
The above aqueous binder dispersion had a coagulation temperature in the range of about 30°-40° C.
A non-woven fabric web consisting of about 30 % nylon fibers and about 70 % cellulose fibers and having a weight of 95 to 100 grams per square meter was impregnated with the above-described aqueous binder dispersion in the apparatus illustrated in the drawing. The binder content, solids basis, of the impregnated fabric was adjusted by squeeze rolls 6 to 100 % based on the dry fiber weight. The linear speed of the fabric was maintained through the apparatus to between about 4 to about 20 meters per minute by squeeze rolls 6.
The fabric web was then exposed to jets of live steam 10 in the heating zone. The steam temperature in pipes 7 was about 130° C; the pressure was about 7.5 p.s.i.g. The vertical spacing between pipes 7 was about 3 centimeters. At a fabric web 1 linear velocity of about 14 meters per minute, the heating zone was about 5 centimeters long. Coagulation of the binder dispersion was instantaneous. When the web was exposed to the jets of steam in this narrower heating zone, the period of steaming necessary to effect coagulation was much shorter than 3 seconds. Respectively for 4, 14 and 20 meters/minute linear speed of the fabric, the period of steaming can be calculated to be, respectively 0.75, 0.21 and 0.15 seconds.
Next, the aqueous residue of the binder dispersion was partly squeezed out by rolls 11. The fabric web was then water washed by passing it over suction cylinder 13 in tank 12. It was then squeezed again between rolls 14 and dried in the oven 15 which raised the temperature in the material to about 150° C. allowing vulcanization to occur.
The ultimate product had a bulk density of 0.465 grams per cubic centimeter. It did not delaminate under stress in any direction sufficient to cause the fabric to break.
EXAMPLE 2
A heat coagulatable aqueous colloidal dispersion of polymeric elastomeric binder was prepared from the ingredients and in the ratio of amounts set forth in the following table:Ingredient Solids weight Solids % Total weight__________________________________________________________________________A carboxylic rubber latexcomprising a cross linkablebutadiene-styrene copolymermodified to include carboxylicgroups in the polymer chain 277,5 kg 55,7 % 500 kgand curable at room temperaturein the presence of zinc oxide(Hycar 2570 × 1)An electrically neutral fattyacid condensation product 4,- kg(Emulvin W)A functional organopoly-siloxane coagulant 4,- kg 16,6 % 60 kg(Coagulant WS)Ammonium chloride 2,- kgWater -- -- 120 kgTotal solids % about 287,5 kg 680 kg 42,4 %__________________________________________________________________________
The above aqueous binder dispersion had a coagulation temperature in the range of about 30°-40° C.
A non-woven fabric web consisting of about 25 % cotton linters, 25 % cellulose fibers and 50 % nylon fibers and having a weight of 200 grams per square meter was impregnated with the above-described aqueous binder dispersion and steam coagulated in the apparatus illustrated in the drawing in the manner described in Example 1.
After being steamed the fabric web 1 was passed through squeeze rolls 11 to remove most of the aqueous residue and steam condensate. Wash tank 12 was bypassed, and the fabric was dried in oven 15 maintained at 150°C. The ultimate product, after drying and vulcanization, did not exhibit objectional harshness due to residual sensitizing agent. It had a bulk density of 0.395 grams per cubic centimeter. The fabric did not delaminate when subjected to destructive stresses. | A process is disclosed for manufacturing flat shaped articles made of individual fibers such as paper, woven fabric, knitted fabric and non-woven fabric impregnated with an aqueous dispersion of a polymeric binder including a sensitizing agent for causing the dispersion to coagulate at a temperature substantially below 100°C. The binder coagulates at a temperature substantially below 100°C. and the method includes impinging live steam on the major surfaces of the article to suddenly coagulate the binder, thereby fixing its position within the fabric and preventing its migration to the fabric's surfaces. One or more adjustable position steam nozzles are used for this purpose. | 3 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] This invention generally relates to the field of heat dissipation. More specifically, the invention relates to a thermosyphon that enhances cooling of electronic systems.
[0003] 2. Description of the Problem
[0004] Cooling of electronic circuit components in thin space enclosures is often performed by metal plates that spread heat, referred to as heat spreaders. Examples of devices where heat spreaders are used include portable computers, high-speed memory modules, inkjet printers, and some handheld devices. A heat spreader's internal thermal resistance, which is a measure of the heat removal performance of a device, increases as the spreader thickness decreases. Size reductions of electronic systems make thinner spreaders necessary. Increasing the thermal conductivity of the spreader can offset the resulting increased internal resistance. One way to achieve very high effective thermal conductivity is to use a fluid-filled cooling device that takes advantage of the heat of vaporization of the fluid by transporting heat from an evaporator to a condenser through the liquid-vapor phase change. Two known types of devices in particular employ this phase-change mechanism for heat transfer from electronic circuit components: thermosyphons and heat pipes.
[0005] Thermosyphons are fluid-filled closed loop devices, incorporating an interconnected evaporator and condenser. The working fluid undergoes a liquid to vapor phase change in the evaporator, thereby absorbing the latent heat of vaporization. The vapor then travels to the condenser, where the heat is lost to the environment and the cooled working fluid condenses to liquid The evaporator is typically oriented vertically with respect to the electronic circuit component to be cooled. The performance of an entirely passive system, where there are no moving parts, requires the condenser to be located vertically above the evaporator. The use of known thermosyphons is therefore limited to enclosures that can accommodate and remain fixed in this required orientation.
[0006] Heat pipes are hollow sealed devices, containing a wick structure saturated with a working fluid. Despite their name, which came from the geometry of the early forms of the devices, heat pipes may be any shape. In their early shape that resembles a pipe, heat is transferred from electronic circuit components, typically the processor chip, to the working fluid in the evaporator portion at one end of the heat pipe. The working fluid undergoes a liquid to vapor phase change in the evaporator portion, thereby absorbing the latent heat of vaporization. This heat is carried by the working fluid to the other end of the pipe, which is the condenser portion, and is rejected to the environment. The cooled working fluid vapor condenses, and urged by the surface tension forces that are generated by the wick structure, returns to the evaporator portion.
[0007] Current known heat pipe structures include flat-plate heat pipes, where heat may be added at any location. The working fluid evaporates, moves to lower pressure and cooler regions of the cavity, and is cooled on the walls of the heat pipe where it condenses. In recently developed micro heat pipes, microfabricated grooves replace the wick structure and provide the capillary action for the return of the condensed vapor to the evaporator portion of the device.
[0008] While heat pipes do not have the geometric orientation constraints of thermosyphons and are an improvement over known heat spreaders, their performance is limited. A significant drawback of the heat pipe comes from its very mechanism, that is, capillary driving of the condensate that makes the heat transfer performance orientation-independent. The capillary action in the heat pipe is based on the thinness of liquid film in the wicking structure, and the difference in liquid/vapor menisci in the condenser and the evaporator. If the liquid film is thick, gravity comes to influence the liquid flow, and the heat pipe performance becomes orientation-dependent. Liquid evaporates as the condensate flows toward the middle of the evaporator section in a flat heat pipe, or toward the end of the evaporator section in a cylindrical heat pipe. The circulation rate of the working fluid in the heat pipe is constrained where the liquid film thickness reduces to zero due to evaporation. A part of the evaporator surface dries, and the surface temperature then increases beyond a level acceptable for the application. This so-called “capillary limit” restricts the application of heat pipes to cases of moderate chip heat dissipation and relatively small heat spreader areas. Larger heat spreader areas inherently have longer wicking structure length, and hence there is more potential for poor performance as a result of the capillary limit. Better thermal performance is desirable to meet the cooling requirements of increasingly faster electronic circuit components.
[0009] There is a need for a device that has superior cooling performance while eliminating the orientation constraints of known thermosyphons. Ideally, the device will be generally orientation-independent, and will be compact in size as necessary to meet thin space enclosure requirements.
SUMMARY
[0010] The thermosyphon of the present invention enhances cooling of electronic systems and has very high effective thermal conductivity while being substantially or fully unconstrained by physical orientation. It has a relatively thin profile as necessary to fit in tight enclosures that are increasingly common in electronic systems.
[0011] The present invention meets the above objects by providing a thermosyphon heat spreader for cooling an adjacent heat-dissipating component, such as a semiconductor chip or other electronic circuit component, referred to as an electronics package. The thermosyphon comprises a central evaporator in contact with the electronics package, a peripheral condenser, or pool belt, that extends around and hydraulically communicates with the evaporator, a liquid coolant that at least partially fills the evaporator and pool belt; and means for cooling the condenser. The central evaporator includes, in one embodiment, two parallel plates of generally similar dimension, with opposing faces of the plates forming the interior surface of the evaporator.
[0012] The thermosyphon may optionally have an opening in the base plate that is sealed against the electronics package and places the heat-dissipating component in direct contact with the liquid coolant. Alternatively, the base plate may be formed with the electronics package from a single piece of material.
[0013] In further accordance with the present invention, a boiling enhancement structure is provided in the evaporator, mounted to the interior surface of the base plate. The boiling enhancement structure may be a plate with grooves that form voids, or an open-celled foam. The means for cooling the condenser may be provided by any known method or device. Such means include, but are not limited to, cooling fins and liquid-cooled jackets that surround the condenser. To optimize performance, gasses are purged from the evaporator and pool belt.
[0014] In yet further accordance with the present invention, the thermosyphon, in another embodiment, has a substantially full or full evaporator for orientations ranging from horizontal to vertical, or from 0 to 90 degrees. In a still further embodiment, the evaporator is substantially full or full for all orientations.
[0015] In a yet further embodiment, a specific geometry thermosyphon according to the present invention is provided. This includes parallel base and cover plates forming the evaporator, and generally U-shaped walls extending from the entire periphery of each plate. The U-shaped walls form the pool belt. One end of the “U” on each wall is connected to the respective base or cover plate, and the other end of the “U” mates with the corresponding end of the “U” on the other plate's wall, with the opening in the “U” facing the opposing plate. The respective geometries of the evaporator and condenser may vary, and dimensions in the orientation-independent embodiment are determined by meeting the design requirement of keeping the evaporator substantially full or full at all orientations while leaving a void in the pool belt where vapor may collect. The planar limits of the evaporator and pool belt may be any shape, for example, square, rectangular, or circular. A thermosyphon is also provided that can be vertically oriented and rotated in a vertical plane such that its edges form an angle with the horizontal plane.
[0016] An enhanced-cooling electronic component is also provided in accordance with the present invention. This component includes a heat-dissipating element, such as a semiconductor chip, a casing in which the element is disposed, and a thermosyphon in accordance with the present invention. A method for cooling a heat-dissipating element is provided that includes using a thermosyphon according to the present invention and placing the thermosyphon in contact with the heat-dissipating element.
[0017] The present invention features use of the latent heat of vaporization of the liquid coolant to provide very high thermal conductivity. The central evaporator and peripheral condenser are symmetric about a central plane, leading to independence of orientation of the thermosyphon heat spreader. Liquid coolant volume is optimized to keep the evaporator substantially full or full at all orientations and yet provide a void in the condenser that allows accumulation of vapor as the coolant evaporates. A boiling enhancement structure encourages nucleation of vapor bubbles by providing re-entrant cavities.
[0018] The foregoing and other features and advantages of the present invention will become more apparent in light of the following detailed description of some embodiments thereof, as illustrated in the accompanying figures. As will be realized, the invention is capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and the description are to be regarded as illustrative in nature, and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 is an exploded perspective view of a thermosyphon according to the present invention.
[0020] [0020]FIG. 2 is schematic top plan view of condenser and evaporator portions of the thermosyphon of FIG. 1.
[0021] [0021]FIG. 3 is a schematic section view of condenser and evaporator portions of the thermosyphon of FIG. 2 taken along line 3 - 3 , with the thermosyphon oriented horizontally and mounted to an electronic circuit component located beneath it.
[0022] [0022]FIG. 4 is a perspective view of a boiling enhancement structure of the thermosyphon of FIG. 1.
[0023] [0023]FIG. 5 is a perspective view of another embodiment of a boiling enhancement structure of the thermosyphon of FIG. 1.
[0024] [0024]FIG. 6 is a schematic section view of condenser and evaporator portions of the thermosyphon of FIG. 3 taken along line 6 - 6 , with the thermosyphon oriented vertically.
[0025] [0025]FIG. 7 is a schematic section view of condenser and evaporator portions of the thermosyphon of FIG. 6 taken along line 7 - 7 , with the thermosyphon oriented vertically and mounted to an electronic circuit component.
[0026] [0026]FIG. 8 is a schematic section view of condenser and evaporator portions of the thermosyphon of FIG. 2 taken along 3 - 3 with the thermosyphon oriented horizontally and mounted to an electronic circuit component located above it.
[0027] [0027]FIGS. 9 through 12 are schematic section views of condenser and evaporator portions of the thermosyphon of FIG. 3 taken along line 6 - 6 , with the thermosyphon oriented vertically and with the edges of the condenser and evaporator portions at various angles away from horizontal.
[0028] [0028]FIG. 13 is a schematic section view of condenser and evaporator portions of the thermosyphon of FIG. 12 taken along line 13 - 13 , with the thermosyphon oriented vertically and mounted to an electronic circuit component FIGS. 14 and 15 are section views of condenser and evaporator portions of other embodiments of vertically oriented thermosyphons according to the present invention.
[0029] [0029]FIGS. 16, 17 and 18 are perspective views of other thermosyphons according to the present invention.
[0030] [0030]FIG. 19 is a graph of junction temperature as a function of heat flux for a modeled heat spreader and experimental results for a thermosyphon according to the present invention, similar to that shown in FIG. 1.
DETAILED DESCRIPTION
[0031] [0031]FIG. 1 illustrates a flat, thin, orientation-independent thermosyphon heat spreader 20 according to the present invention. The thermosyphon 20 comprises a base plate 22 and a cover plate 24 . The base plate 22 and cover plate 24 mate, causing recessed areas in the plates to define a phase-change heat transfer system 26 , including a central evaporator region 28 in hydraulic communication with a peripheral condenser region 30 . The condenser region 30 is referred to as a pool belt. Means for cooling the pool belt 30 are provided in the present embodiment by cooling fins 32 . The evaporator 28 preferably includes a boiling enhancement structure 34 . Liquid coolant, not shown, at least partially fills the evaporator 28 and pool belt 30 , and an elastomeric gasket, placed in the groove 35 around the periphery of the pool belt, imperviously seals the connection between the base and cover plates 22 , 24 .
[0032] The material selection for the base and cover plates 22 , 24 depends on application requirements for ease of fabrication and service reliability. Aluminum may be desirable if used with inert liquid coolants and at relatively low temperatures because of its ease of machinability and lower density compared to other metals. However, corrosion concerns make aluminum an inappropriate choice if water is the liquid coolant and the temperature is not low. Materials with better thermal properties, like copper, can be used to make the plates 22 , 24 , and other metals may be used as selected by someone of ordinary skill in the art. In addition, metal matrix composites such as aluminum silicon carbide (AlSiC) may be used if the residual stresses between the plate material and a silicon-based substrate that is the adjacent electronic circuit component, resulting from the mismatch in the coefficient of thermal expansion, are a concern.
[0033] The base plate 22 and cover plate 24 are substantially planar in geometry. Each plate 22 , 24 has a first major surface and a second major surface. The major surfaces coincide with the substantially planar geometry of the plates 22 , 24 , and are the largest faces of the plates 22 , 24 . Although the terms “base” and “cover” are sometimes used with reference to orientation such as “bottom” and “top,” the use of the terms “base” and “cover” herein should not be considered to restrict orientation. Rather, the “base” plate 22 is merely the plate that is proximate to a component to be cooled, and the “cover” plate 24 opposes and is spaced from the base plate 22 . In addition, the evaporator 28 may be formed from a first and a second plate, that may or may not be portions of a respective unitary base plate 22 or cover plate 24 .
[0034] The limits of the evaporator 28 , pool belt 30 , and boiling enhancement structure 34 in the phase-change heat transfer system 26 of the thermosyphon 20 according to the present invention are schematically illustrated in FIGS. 2 and 3. For simplicity of description, the shape of each of these features in top (plan) view (FIG. 2), i.e. the planar shape, is square and in cross-section (FIG. 3) is rectangular, and the dimensions are not to scale, but the features may be any shape as desired to suit a particular application or manufacturing advantage. Again for simplicity, only the interior surfaces, i.e. walls 36 , of the heat transfer system 26 of the thermosyphon 20 are shown. In the horizontal position shown in FIG. 3, the liquid coolant 38 preferably fills the evaporator 28 and partially fills the pool belt, leaving a void 40 .
[0035] For indirect liquid cooling the evaporator 28 is mounted directly to an electronic circuit component, or electronics package 42 . The contact between the base plate 22 and the electronics package 42 is made on a free major surface 44 of the electronics package. This free major surface 44 is a surface of the electronics package 42 that is, prior to mounting of the thermosyphon 20 , unattached, generally planar, and frequently a portion of the electronics package with the largest surface area. In this embodiment, the base plate 22 and cover plate 24 can be identical. Alternatively, to provide direct liquid cooling of the electronics package 42 , the electronics package can be integrated into the base plate 22 , immersing the electronics package in the coolant 38 . Such integration may be done by sealing a base plate 22 that has an opening in it to the electronics package 42 , by fabricating the base plate and electronics package from one piece of material, or by other means known to someone of ordinary skill in the art.
[0036] A variety of working fluid liquid coolants 38 can be used based on several factors including, but not limited to, boiling or evaporation temperature, chemical compatibility with the components of the evaporator unit in case of indirect liquid cooling and with the electronic package in case of immersion cooling, chemical stability, toxicity and cost. Coolants that are preferred for use with the invention include ethyl alcohol and fluorochemicals, such as FLUORINERT™ (FLUORINERT is a trademark of and is manufactured by the Minnesota Mining and Manufacturing Company, St. Paul, Minn.).
[0037] The system 26 is preferably purged of residual gasses to improve heat transfer performance. The void 40 is evacuated in advance of using the thermosyphon 20 in order to reduce pressure and eliminate resistance to the liquid-to-vapor phase change. The presence of residual gasses not only deteriorates the heat transfer characteristics of the system, but in the case of FLUORINERT™ liquids, residual gasses also change the properties of the coolant. Also, sub-atmospheric pressures ensure removal of heat at high heat fluxes while maintaining low surface temperatures on the walls of the pool belt 30 .
[0038] In the Figures herein, unique features receive unique numbers, while features that are the same in more than one drawing receive the same numbers throughout. Where a feature is modified between figures, a letter is added or changed after the feature number to distinguish that feature from a similar feature in a previous figure.
[0039] The boiling enhancement structure 34 is a porous component that provides re-entrant cavities 46 . One such structure 34 a is illustrated in FIG. 4. Re-entrant cavities 46 have the characteristic ability to entrap vapors, thereby becoming active nucleation sites for the formation of vapor. For example, a single layer structure 34 a is made from a square plate with parallel rectangular channels that define the re-entrant cavities 46 , preferably cut to more than half the thickness of the layer from major surfaces 47 , 48 on each side of the plate. These channels intersect to form square cavities 46 , which in turn act as sites for vapor bubble nucleation. The heat transfer performance of the thermosyphon system depends on optimizing the channel width W C and pitch P C of the porous microstructures employed. Maximizing heat dissipation, in turn, depends on selection of the working fluid 38 . In an indirect liquid cooling configuration, the boiling enhancement structure is attached to the center of the evaporator section of the thermosyphon plate. Good thermal contact between the porous enhancement structure 34 a and the evaporator 28 may be achieved through the use of a thin paste of solder or high thermal conductive epoxy. In a direct immersion cooling configuration, the enhancement structure 34 is directly attached on the passive side of the electronics package 42 die surface, eliminating the contact resistance inherent when there is heat transfer across adjacent mating surfaces.
[0040] Boiling enhancement structures 34 a with channels may be made from a variety of materials such as copper, diamond, silicon, or other as selected by someone of ordinary skill in the art, and may be a variety of shapes. The micro-channels may be made by techniques such as wet-chemical etching, laser milling, or wafer dicing, or other known processes.
[0041] The width W C and pitch P C are determined by thermal considerations as well as convenience in assembling multilayer enhancement devices 34 b, as shown in FIG. 5. Thermal considerations require an analysis of benefits and costs related to performance. As the pitch P C increases, heat conduction paths in solid parts become wider and thereby conduct more heat from the device base to the end, while at the same time the number of channels on a fixed device footprint area decreases, reducing the area available for heat transfer. As illustrated in FIG. 5, the boiling enhancement structure can be made of stacked single layers 34 a to make the multiple layer structure 34 b. Assembly requires securing sufficient interfacial areas to stack and bond component plates. In operation, the structural integrity of the device 34 b depends on the bonding strength, which also relies on the interfacial area. Experiments have been carried out on the enhancement structures 34 a, 34 b for channel widths W C ranging from 40-320 μm and pitches P C from 0.5-3.0 mm.
[0042] As an alternative to this type of micro-channel structure 34 a, 34 b, commercially available open-celled porous foam may also be used to make the structure 34 . Examples of suitable foams include DUOCEL® aluminum and silicon carbide foams from ERG Materials and Aerospace Corporation of Oakland, Calif. (DUOCEL is a registered trademark of Energy Research and Generation, Inc. of Oakland, Calif.) and INCOFOAM® nickel foam from Inco Limited of Toronto, Canada (INCOFOAM is a registered trademark of Inco Limited).
[0043] Optimizing design of the system 26 depends on one factor in particular: For any given orientation, the evaporator 28 should be substantially full of liquid coolant 38 . As shown in FIG. 3, the pool belt 30 has a greater height, H B , than that of the evaporator 28 , H E . In a horizontal orientation, again as shown in FIG. 3, the depth D of the coolant 38 is preferably at least approximately (H B +H E )/2.
[0044] Each different shape of phase-change heat transfer system 26 will have an orientation on which the design needs to be based. For a square planar shape such as the geometry shown in FIGS. 2 and 3, the requirement of keeping the evaporator substantially full determines the dimensions of the evaporator 28 , H E and L E , and the pool belt 30 , H B and L B .
[0045] To keep the evaporator 28 completely full in the vertical orientation shown in FIGS. 6 and 7, and as a result, at least substantially full in all orientations, with the coolant depth approximately equal to (H B +H E )/2 when in a horizontal orientation, the dimensions of the system 26 must approximately satisfy the following equation:
H B /H E =2(1 +L B /L E ).
[0046] Conformance to this equation also provides a completely full evaporator in either horizontal orientation, as shown in FIGS. 3 and 8, regardless of which of the base plate 22 or cover plate 24 is on top. Where the term “approximately satisfy” or the like is used herein, it means that the referenced equation need not be exactly true, but requires only that the values calculated on each side of the equation provide a thermosyphon that performs in the spirit of the present invention. Where the term “substantially full” or the like is used herein to describe the evaporator, it means that the evaporator volume, i.e. the volume defined by the plates forming the evaporator, contains a quantity of liquid coolant adequate to provide a thermosyphon that performs in the spirit of the present invention, and includes a range of coolant quantities equal to or less than a completely full evaporator.
[0047] [0047]FIG. 8 schematically illustrates a system 26 that conforms to this equation, and has a completely full evaporator 28 when oriented as shown, rotated 180 degrees from the orientation shown in FIG. 3. The pool belt 30 must be vertically symmetric about the evaporator 28 to achieve this result when the coolant level approximately conforms to the (H B +H E )/2 criterion in the horizontal orientation. An asymmetric pool belt 30 can result in a system 26 that has a substantially full evaporator 28 only in certain orientations. For example, the evaporator 28 may be substantially full from a horizontal orientation through rotation to a vertical orientation, but past that vertical orientation the evaporator may not be substantially full. Such a thermosyphon may be designed in accordance with the present invention by one of ordinary skill in the art.
[0048] [0048]FIG. 9 shows a square-shaped system 26 that is oriented with the limits of the evaporator 28 and condenser 30 at an angle θ* to horizontal. The angle θ* is fixed by the dimensions of the system 26 and is given by the following equation:
θ * = tan - 1 ( L B L B + L E )
[0049] When the system 26 is in a vertical orientation and is tipped to an angle of θ*, the surface of the coolant is at the uppermost point of the evaporator 28 and at the second highest corner 49 of the condenser 30 . The dimensions of the square system 26 may be modified to provide a filled evaporator for any given angle θ, depending on whether θ is less than or greater than θ*, as shown in FIGS. 10 and 11.
[0050] In FIG. 10, the system 26 is at an angle θ that is greater than 0 degrees and less than or equal to θ*. In FIG. 11, the system 26 is at an angle θ that is greater than or equal to θ* and less than or equal to 45 degrees. Approximately satisfying the condition of a coolant 38 depth of (H B +H E )/2 when in the horizontal orientation and the following equations when in rotated vertical orientations (as shown in FIGS. 10 and 11) provides a full evaporator for a given angle θ.
H B H E = 2 ( 1 + L B L E ) L B L E L B L E + ( 1 2 + L B L E ) tan θ
H B H E = 1 + L B L E 1 + 1 2 { 1 - 1 2 ( tan θ + cot θ ) } L B L E
[0051] [0051]FIGS. 12 and 13 show a square system 26 that is vertically oriented and rotated to where θ is 45 degrees. At relatively larger angles θ, depending on the application and the possibility of other orientations, such as other angles θ or horizontal orientations for example, the volume of coolant 38 can become excessive, and inhibit performance of the system 26 because of an inadequate void volume 40 . The appropiate volume of coolant 38 can be determined by one of ordinary skill in the art based on use of the above equations, the application, and possible orientations of the system 26 .
[0052] Any other planar shape, in addition to square, may be used for the evaporator 28 and pool belt 30 limits, and the respective shapes may differ within one embodiment. FIGS. 14 and 15, respectively, show rectangular and circular planar-shaped embodiments of phase-change heat transfer systems 26 a, 26 b. Schematic cross-sections for the rectangular and circular embodiments shown in FIGS. 14 and 15 look similar to those shown in FIGS. 3 and 8. Likewise, different shapes may be used for the boiling enhancement structure 34 .
[0053] The rectangular phase-change heat transfer system 26 a shown in FIG. 14 should conform to the following equation to have a substantially full evaporator in all orientations:
H B /H E =(2 L B +L E +W E )/ L E
[0054] It should be understood that the thermosyphon 20 of the present invention can function both with the evaporator 28 being less than full or with the system 26 holding liquid coolant 38 in excess of the preferred amount. To be sure that the system 26 , 26 a functions to nearly full capability at all orientations, however, it is desirable to conform to the design criteria described above. This design also results in the evaporator 28 a being completely full in both horizontal orientations as well as vertical orientation, as shown in FIGS. 3, 6 and 8 . The round system 26 b shown in FIG. 15 having a coolant 38 depth of (H B +H E )/2 when in a horizontal orientation and dimensions that approximately satisfy the following equations provides a completely full evaporator in all orientations:
φ = 2 ( 1 - ( R E R B ) 2 ) ( 1 - H E H B ) + R E R B 1 - ( R E R B ) 2 φ = cos - 1 ( R E R B )
[0055] where R E is the radius of the evaporator, R B is the radius of the pool belt 30 b, and φ is the angle formed between vertical and a pool belt radius line when the outer end of the pool belt radius line and the coolant 38 meet at the outer limit of the condenser 30 b and the coolant 38 completely fills the vertically oriented evaporator 28 b.
[0056] If the evaporator 28 is not full at a vertical orientation, at that vertical orientation there will not be coolant 38 in contact with the entire evaporator base plate 22 , and the heat flux to the coolant 38 will be reduced. If at an orientation that is 180 degrees from that in FIG. 3, as illustrated in FIG. 8, the evaporator 28 is not full, the base plate 22 will not contact the coolant 38 at all. It is also desirable not to overfill the system 26 . A liquid coolant 38 charge larger than required by the formulas described above guarantees filling of the evaporator in horizontal as well as vertical orientations. However, a designer must take into account the fact that the volume of two-phase mixture increases due to expansion when the device 20 is in operation. Hence, overfill of the system 26 would result in less space available for the vapors to condense and would increase pressure in the system 26 , which could impact performance.
[0057] The saturation temperature of the coolant 38 depends on the system 26 pressure. Overfilling the system 26 would in effect, therefore, change the saturation temperature of the coolant 38 and in turn affect the system performance. The mass of the working fluid 38 at the time of charging the system 26 depends both on heat transfer performance considerations and the structural integrity of the thermosyphon 20 . In addition to the heat transfer performance of the boiling enhancement device 34 in the evaporator 38 and that of the condenser 30 walls, the appropriate mass of working fluid 38 also depends on the heat transfer performance of the air-cooled surface or alternative heat sinks, the operating temperature of the heat source, and the allowable internal pressure in the thermosyphon 20 . These parameters require evaluation for each application and design, and may be determined by one of ordinary skill in the art.
[0058] The cooling of the pool belt 30 in order to condense the vapor of the liquid coolant 38 can be performed in any one of a variety of ways that are know in the art. For example, the cooling fins 32 of FIG. 1 could be made hollow to communicate with the interior of the pool belt 30 . This would increase the amount of surface area presented to the coolant 38 vapor within the pool belt 30 , and in turn increase the heat transfer from the vapor to the pool belt. Another embodiment of the thermosyphon 20 a according to the present invention is shown in FIG. 16. This embodiment includes a watercooled jacket 50 . The cover plate 24 a initially has two openings, not shown in the Figures, that respectively provide hydraulic connections to a vacuum pump line to evacuate the system 26 and to a supply line for filling the system with coolant 38 . These openings are closed after the system 26 is charged with coolant 38 and evacuated. A permanent opening 52 in the cover plate 24 a provides a hydraulic connection to a water supply line 56 that provides water to the cooling jacket 50 . The base plate 22 has an opening 54 providing a hydraulic connection to a discharge line 58 that carries away the cooling water from the jacket 50 . This thermosyphon 20 a is referred to as an indirect, liquid-cooled thermosyphon because the working fluid 38 is not in direct contact with the heat source and the phase-change heat transfer system 26 is cooled with liquid.
[0059] Another thermosyphon 20 b according to the present invention and having a water-cooled jacket 50 is shown in FIG. 17. This embodiment 20 b is shown with an opening 60 in the base plate 22 b to accommodate a boiling enhancement structure 34 that is attached directly to a semiconductor chip package, shown as a Pin Grid Array (PGA) package 42 a. The package 42 a is one of many electronic components known to those of ordinary skill in the art that may be used with the present invention, and includes a semiconductor chip 62 and casing 64 . The opening 60 brings the liquid in direct contact with the PGA package 42 a, and is therefore referred to as a direct, liquid-cooled thermosyphon. A seal, such as an elastomeric or other type of seal placed in a groove 66 in the PGA package 42 a, is provided between the mating surfaces of the PGA package 42 a and the bottom plate 22 b, as known to one of ordinary skill in the art.
[0060] Another water-cooled thermosyphon 20 c according to the present invention is shown in FIG. 18. The heat sink in this thermosyphon 20 c comprises fins 32 c that are integral to and extend from the free surface of the cover plate 24 c. The cover plate 24 c and fins 32 c may be made from one piece of material, or from more than one piece of material and attached to each other by means known to one of ordinary skill in the art.
[0061] For experimental evaluation, a prototype of the thermosyphon according to the present invention similar to that shown in FIG. 1 was constructed from aluminum with fifty-two straight rectangular fins cut along the sides. The prototype comprised two plates of 2.25-mm thickness and had a square evaporator section of 30-mm length (L E ) in the middle. The thickness of the pool belt was 5 mm (L B ), making the outer limit of the pool belt 40 mm by 40 mm. The height of the pool belt (H B ) was 3.5 mm and the height of the evaporator (H E ) was 1.5 mm. The fins had a length of 16.5 mm and were cut out along the sides of each plate to help in heat rejection to ambient air. The two plates along with the peripheral fins resulted in an 89.5-mm by 89.5-mm by 4.5-mm thermosyphon. A 14-mm by 14-mm thermal test die package was used to simulate the chip heating conditions by controlling the temperature of the test package in contact with the thermosyphon. FIG. 19 compares the experimental performance of the thermosyphon with modeling results performed for a flat aluminum plate having modeled fins and the same outside dimensions as the prototype. A commercially available finite element software package was used for the model. The heat transfer and condenser boundary conditions of the thermosyphon experiment were replicated in the model. Natural convection correlations were used to specify the heat transfer coefficients on the upward facing surface of the modeled aluminum plate and along the fin surfaces at the plate edges. The heat source condition was simulated in the model by applying a uniform heat flux at the bottom along an area equal to the chip size. The remaining area along the bottom was modeled to be adiabatic.
[0062] A maximum heat flux of 6.3 W/cm 2 was achieved with the prototype thermosyphon under natural air-cooled conditions, with the junction temperature, which was taken as the average of the temperature measured by two thermistors embedded in the die, at 74.6° C. At the maximum heat flux, the junction temperature with the prototype thermosyphon was found to be 47.6° C. less than the junction temperature for an identical thickness modeled aluminum heat spreader. The junction temperature for the modeled aluminum spreader was taken to be the average temperature of the evaporator model. This is comparable to the performance of conventional, orientation-dependent thermosyphons that are commonly much thicker, and well exceeds the performance of conventional heat spreaders. When manufactured on the small scale required for cooling of individual semiconductor chips and other electronic packages, a microchannel boiling enhancement device improves performance both by facilitating boiling and by drawing the working fluid deep into the thin space of the evaporator.
[0063] The thermosyphon according to the present invention offers significant advantages over known heat pipe technology. This thermosyphon exploits gravity to maintain working fluid circulation. Although there is a certain limit to the heat removal capability even in gravity-assisted heat removal systems, such limits are usually higher than the capillary limit of heat pipes by about an order of magnitude. High heat removal capability is derived from ample supply of liquid to the evaporator. Although the present invention relies on gravity for working fluid circulation, the geometrical design of the enclosure results in orientation independence, unavailable in conventional thermosyphons.
[0064] Specific embodiments of the present invention are described above that provide enhanced cooling of electronic circuit components. One of ordinary skill in the heat transfer and electrical arts will quickly recognize that the invention has other applications in other environments. In fact, many embodiments and implementations are possible. For example, the shapes, sizes, and configurations of the thermosyphon heat spreader may be varied from those discussed without departing from the scope of the present invention. The following claims are in no way intended to limit the scope of the invention to the specific embodiments described. | Device for enhancing cooling of electronic circuit components that is substantially or fully independent of orientation. A thin profile thermosyphon heat spreader mounted to an electronics package comprises a central evaporator in hydraulic communication with a peripheral condenser, both at least partially filled with liquid coolant. A very high effective thermal conductivity results. Performance is optimized by keeping the evaporator substantially full at all orientations while leaving a void for accumulation of vapor in the condenser. A cover plate and a parallel base plate of generally similar dimension form the evaporator and condenser. Optionally, an opening in the base plate is sealed against the electronics package and places the heat-dissipating component in direct contact with the liquid coolant. Alternatively, the base plate may be formed with the electronics package from a single piece of material. A boiling enhancement structure is provided in the evaporator to encourage vapor bubble nucleation. | 5 |
BACKGROUND OF THE INVENTION
This invention relates in general to a circuit for measuring the duration of a pulse train and more particularly to such a circuit for providing fading compensation radio receivers.
A circuit for measuring the duration of a pulse train has been disclosed in the journal "Elektronik", 1966, pp. 143 to 146, FIG. 9, page 145. In this circuit a counter, during the period to be measured, or an integer multiple thereof serving as the measuring period, counts pulses which are derived from an oscillator serving as the time base. A gate or sequence-control circuit controlled by the pulse train to be measured, is used to control the counter in such a way that the aforementioned oscillator pulses are counted only during the measuring period. The counter reading (count) is made visible with the aid of an indicating or display arrangement for which it is possible to use the most various types of nowadays customary electronic indicating or display means (digital display tubes, LED's, seven-segment displays, etc.).
In particular fields of practical application of such period or duration measuring circuits it is also customary to provide a memory (storage device) beween the counter output and the indicating arrangement, in which the respective count is temporarily stored. This arrangement is customary, for example, with traffic decoders which, among others, also decode the service area identification signal, German Patent Application DE-OS No. 25 18 104. The general principles for designing a traffic radio system may be found in the German technical journal "Funkschau", 1974, pp. 535 to 538.
In conventional circuits for measuring the duration of a pulse train, for example, when designed as service area identification decoders for traffic radio signals, or when designed as a digital voltmeter, it is necessary to make both the measuring and the display insensitive with respect to interferences to which the pulse train to be measured may be subjected. These interferences may become noticeable, on one hand, in that individual pulses are missing and, on the other hand, also in that additional pulses are superposed, or else in that the pulse periods vary. The conventional arrangement according to DE-OS No. 25 18 104, in which instead of the pulses of an oscillator, the oscillations of the 57-kHz identification are counted in the counter following a corresponding frequency division, eliminates these interferences to a certain extent, in that a predetermined count range is used for indicating the same service area identification symbol, that is, within the count range between 16 and 20, the service area "A" is displayed. In this, the rated display is e.g. at the count 18, so that per measuring period it is possible to tolerate a variation of ±2 pulses of the divided 57-kHz identification oscillation.
SUMMARY OF THE INVENTION
It is an object of this invention as defined in the claims, to refine the well known suppression of interferences in such a way that also in the case of longer lasting interferences, the period which occurred prior to the interference, will still be displayed during the interference, and that in response to a change of period, the new period is only displayed after selectable delay time.
According to this invention there is provided a circuit for measuring the period of a pulse train comprising a counter for counting pulses during a period or integer multiple thereof serving as a measuring period, which pulses are derived from an oscillator serving as time base, a memory for storing the count available at the end of the measuring period, an arrangement for indicating the memory contents, a sequence control controlled by the pulse train, a coincidence gate for comparing the count of the counter as achieved after each measuring period with the contents of the memory, and a bidirectional (forward-backward) counter to the counting input of which one counting pulse is applied per measuring period whose counting direction is switched by the coincidence gate to a forward counting in the event of an equality of both the count and the memory contents, but to backward counting in the event of an unequality, which blocks its counting input upon reaching its highest count or its zero position, when simultaneously switched to forward counting or backward counting by the coincidence gate, and which only in its zero position permits the count to be read into the memory.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will now be explained in greater detail with reference to examples of embodiments shown in FIGS. 1 to 4 of the accompanying drawings, in which:
FIG. 1, in the form of a block diagram, shows one example of embodiment of the circuit according to this invention,
FIG. 2 shown a preferred type of sequence control which, in the block diagram of FIG. 1, is only shown schematically,
FIG. 3 shows the signal waveforms as appearing at the various outputs of the sequence control according to FIG. 2, and
FIG. 4, in the form of a diagram, shows one possible sequence of counts of the bidirectional counter according to FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the example of embodiment of the circuit shown in FIG. 1, the oscillator 1 serving as a time base produces pulses, preferably rectangular pulses which are fed to the input 21 of the counter 2. The pulse train whose duration is to be measured, is applied to the measuring input E of the circuit. This pulse train is applied from the measuring input E to the input 31 of the sequence control 3, the five outputs 35, 36, 37, 38, 39 of which are connected in a way still to be described hereinafter, to the further partial circuits, with the temporal assignment of the signals thereof controlling the intended measuring operation.
Thus, the output signal of the first output 35 is applied to the condition input 20 of the counter 2, upon activation of which the counting operation is released via the counter input 21. The second output 36 of the sequence control 3 is connected to the reset input 29 of the counter 2, so that an output signal appearing at the second output 36 will serve to reset the counter 2 via the reset input 29.
The counter reading outputs 25 . . . of the counter 2, via corresponding lines which, in FIG. 1, are indicated by the shown arrow with three hatchlines, are connected to the one part of the inputs 41 . . . of the coincidence gate 4, while the other part is connected to the inputs 51 . . . of the memory 5. The third output 37 of the sequence control 3 is connected to the condition input 40 of the coincidence gate 4 for serving the comparison, so that an output signal appearing at this particular output will trigger the comparison operation of the coincidence gate 4.
The input stage of the bidirectional counter 6 consists of four logic gates, each having two inputs, namely the two NAND-gates 601, 602, the AND-gate 603 connecting the outputs thereof, as well as the AND-gate 604 connecting the output thereof, as well as the fifth output 39 of the sequence control 3.
The first output 47 of the coincidence gate 4 conditioning the forward counting direction of the bidirectional counter 6, is connected to the one input of the first NAND-gate 601, while the second output 48 of the coincidence gate 4, conditioning the backward counting direction of the bidirectional counter 6, is applied to the one input of the second NAND-gate 602. The second input of the first NAND-gate 601 is connected to the counter reading output 659 serving the highest count of the bidirectional counter 6, and the second input of the second NAND-gate 602 is applied to the counter reading output 650 serving the zero setting of the bidirectional counter 6.
Moreover, the first output 47 of the coincidence gate 4 is connected to the forward-condition input 67, and the second output 48 to the backward-condition input 68 of the bidirectional counter 6. One of the lower counter reading outputs, hence the counter reading output 651 serving the count one in the example of embodiment shown in FIG. 1, finally, is connected to the blanking input 79 of display 7 whose input 71 is connected to the inputs 51 . . . of the memory 50, at which the information to be displayed appears permanently.
In the example of embodiment shown in FIG. 1, the control stage of the memory 5 consists of the third AND-gate 501 whose first input is connected to the fourth output 38 of the sequence control 3, and whose second input is connected to the counter reading output 650 serving the zero setting of the bidirectional counter 6.
As one preferred example of embodiment relating to the sequence control 3, FIG. 2 shows an arrangement containing the pulse shaper 301, which is preferably a Schmitt trigger, as well as the first and the second binary divider 302, 303, the fourth, fifth and sixth AND-gates 304, 305, 306, and the third NAND-gate 307. From the arbitrarily shaped pulses as applied to the input E, the pulse shaper 301 forms rectangular pulses having a pulse duty factor of about 0.5 which are directly applied to the fifth output 39 and are fed from there, as already mentioned, to the second input of the second AND-gate 604. Moreover, the output signal of the pulse shaper 301 is applied, on one hand, directly to the input of the binary divider 302 and, via one input of the fourth AND-gate 304, also to the input of the binary divider 303. The Q-output of the first binary divider 302 is applied to the one input of the fifth AND gate 305, while the Q-output of the first binary divider 302 is applied to the second input of the fourth AND-gate 304. Accordingly, by inserting the fourth AND-gate 304, it is achieved that the pulse duration of the input signal of the second binary divider 303 becomes equal to that of the input signal of the first binary divider 302.
The second input of the fifth AND-gate 305 is applied to the Q-output of the second binary divider 303 and to the second input of the sixth AND-gate 306 whose first input is applied to the Q-output of the first binary divider 302. The output signal of the sixth AND-gate 306 is applied to the second output 36 which, as already mentioned hereinbefore, and via the reset input 29, controls the resetting of the counter 2.
The Q-output of the second binary divider 303 is applied to the first output 35 which, via the condition input 20 of the counter 2, controls the beginning and the end of the counting operation thereof. The output of the fifth AND-gate 305 is applied to the third output 37 which, via the condition input 40 of the coincidence gate 4, triggers the comparison between the count of the counter 2 and the storage contents of the memory 5, and terminates this operation.
Moreover, the output of the fifth AND-gate 305 is applied to the second input of the third NAND-gate 307 to the first input of which the output signals of the pulse shaper 301 are applied, and whose output signal, via the fourth output 38 and the first input of the third AND-gate 501, dynamically controls the takeover of the count (counter reading) 25 . . . into the memory 5.
For enabling a better understanding of the invention FIG. 3 shows some signal waveforms of the type as occurring in the arrangement according to FIG. 2 FIG. 3a shows the waveform of the output signal of the pulse shaper 301 and consequently, also of the signal as appearing at the fifth output 39 of the sequence control 3. This signal represents the pulse train F which is to be measured. By a single binary division carried out in the first binary divider 302 there will result from the signal waveform of FIG. 2a, that as shown in FIG. 2b, as appearing at the Q-output Q 302 of the first binary divider 302. By a repeated frequency division carried out in the second binary divider 303 there will appear at the first output 35 the signal waveform as shown in FIG. 3c. Owing to the chosen logical interconnection, the waveform as shown in FIG. 3d will appear at the output of the fifth AND-gate 305 and, consequently, also at the third output 37, while at the output 36, there will appear the signal waveform as shown in FIG. 3e. Finally, the signal waveform as shown in FIG. 3f appears at the output 38. All of the partial circuits of the sequence control 3 operate in a so-called positive logic, that is, upon application of the upper binary signal level H to the two inputs of an AND-gate, an H-level is likewise supposed to appear at the output thereof. Relative thereto, the L-level corresponds to the low binary signal level.
It can be easily seen from the signal waveforms of FIG. 3, that the measuring period T during which pulses from the oscillator 1 of FIG. 1 reach the counter 2, covers four periods of the pulse train F, hence is equal to the period of the output signal of the second binary divider 303. Moreover, it can be seen from FIG. 3, that during the first half of each measuring period T, hence while the signal at the Q-output of the second binary divider 303 assumes the H-level, the counter 2 can count pulses from the oscillator 1. Furthermore, during the third quarter of each measuring period T, hence while the signal at the third output 37 assumes the H-level, the coincidence circuit 4 compares the just reached count of the counter 2 with the count just stored in the memory 5. During the last quarter of each measuring period T, hence while the signal at the output 36 assumes the H-level, the counter 2 is reset, and at the end of the fifth eighth of each measuring period T, the just reached count of the counter 2 is read into the memory 5 dynamically, with this being indicated by the downwardly directed arrow in FIG. 3f.
Further signal waveforms are shown in FIG. 4. Thus, FIG. 4a, again shows the pulse train F in the course of which, in fact, there appears a gap which is due to an interference, but which is not visible in the display of the display arrangement 7. FIGS. 4b and 4c show the respective output signal at the first and second output 47, 48 of the coincidence gate 4, with an H-level at the first output 47 at the same time meaning an L-level at the output 48, and vice versa. Merely, for the sake of a better understanding, the drawing shows a pulse duty factor of 0.5; in the most simple case, of course, the pulse duty factor has the value of 0.25. FIG. 4d shows the course of the counts 65 . . . of the bidirectional counter 6 relating to an assumed signal waveform of the pulse train F. Together with the H-level at the counter reading output 650 serving the zero setting of the bidirectional counter 6 (FIG. 4e) there will thus result the shown signal waveform.
In order to be able to understand the following explanation, it is necessary to count the pulses of the pulse train F in FIG. 4a consecutively from the left to the right. Thus, at the first pulse, the count of the bidirectional counter 6, by starting from a not particularly stated previous count, will assume the count 651. At the second pulse the H-level at the second output 48 of the coincidence gate 4 indicates the unequality of both the count of the counter 2 and the contents of the memory 5, so that the bidirectional counter 6, via its backward-condition input 68, is switched in the backward direction and, owing to the pulse applied via its input part, assumes the zero position 650. At the third pulse of the pulse train F, the coincidence gate 4 will again determine the equality of both the count of the counter 2 and the contents of the memory 5, so that owing to the H-level at the first output 47, the bidirectional counter 6 via its forward-condition input 67, is switched in the forward direction and, via the pulse applied via its input part, reassumes the count (reading) 651. The same is repeated at the fourth and the fifth pulse of the pulse train F, so that the count of the bidirectional counter 6 has now arrived at three. By the sixth pulse of the pulse train F, the bidirectional counter 6 is again switched to the backward direction and is reset by one, while at the seventh pulse there is again switched to the forward direction, and counted correspondingly. Now there appears the aforementioned gap in the pulse train F, and since the sequence control 3 forms all control signals from the pulse train F, the entire measuring process will so to speak comes to a standstill on the already reached results.
Following the gap which is due to an interference, and during the eighth, ninth and tenth pulse, there is again determined the equality between the counter reading and the memory contents, with the counter thus being counted up to the highest count (reading) 659. Also at the eleventh pulse at which there is again determined the equality between the count and the memory contents, the bidirectional counter 6 remains at its highest count 659, because a counting pulse is not permitted to pass by the input stage thereof. The input stage of the bidirectional counter 6, incidentally shows a similar behavior upon reaching the zero position 650 in the case of a simultaneous backward counting direction.
Accordingly, with respect to signal gaps which are due to interferences, or in the case of any other momentary variations of the period to be measured, the circuit of the invention shows to have an integrating character, so that this will only lead to a corresponding change in the display arrangement 7 after there has been detected a change in the period to be measured, extending over several counting cycles of the bidirectional counter 6. The integrating time, hence the aforementioned delay time, is determined by the counting capacity of the bidirectional counter 6, and is set thereby.
The circuit according to the invention can be used particularly well in a traffic decoder, with the measuring period T being derived from the aforementioned service area identification oscillation, and the oscillator 1 preferably being a crystal oscillator, that is, to the input E of the circuit according to the invention there are applied the a.c. signals of corresponding frequencies relating to the service areas A . . . F, as known in detail from pages 535 to 538 of the German technical journal "Funkschau", 1974. Accordingly, owing to the already mentioned integrating effect, especially when used as a traffic decoder decoding the service area indentification signals, the individual areas are automatically displayed, and a switching of the display from one area identification code to another one is only released when the static errors have decayed below the extent of the interference suppression as determined by the maximum count (reading) of the bidirectional counter 6.
For realizing the circuit according to the invention it is particularly suitable to employ the monolithic integrated circuit technique. In one preferred kind of realization, there is used the well known so-called integrated injection logic (I 2 L) technique.
Whereas this invention has been described with respect to specific embodiments thereof, it will be understood that various changes and modifications will be suggested to one skilled in the art, and it is intended to encompass such searches and modifications as are within the scope of the appended claims. | A circuit is provided for the fading compensation in car radio receivers equipped with the so-called traffic decoder decoding for example the area designating signal. An up-down counter, a memory and a coincidence gate are interconnected to maintain the measured pulse duration over a selectable time period. | 6 |
TECHNICAL FIELD
The present invention relates to a portable electric angle grinder for use in grinding or polishing a workpiece.
BACKGROUND
An ordinary electric angle grinder typically includes: a housing; a working mechanism disposed on a head portion of the housing and configured to grind or polish a workpiece; a motor disposed within the housing and configured to drive the working mechanism; a switch disposed within a handle portion of the housing and configured to activate or deactivate the motor; and a lever disposed right under the switch and configured to allow an operator to operate the switch in the housing through manipulating the lever. Once the motor is switched on, a grinding wheel of the working mechanism starts to rotate at a very high speed, during which, if the operator improperly operates the tool or is unfamiliar with the tool, the grinding wheel rotating at a very high speed might lead to body injury. For this reason, the grinder generally further includes a lock means disposed in proximity of the lever in order to prevent operation mistakes as much as possible.
Examples in this regard include a working tool as disclosed in PCT App. No. PCT/JP2009/065259, entitled “Working Tool”. In one embodiment, the working tool is an electric angle grinder including: a motor for driving a grinding wheel to grind or polish a workpiece; a motor housing for housing the motor, the motor housing having a portion defining a handle; a wheel guard coupled to a rear portion of the motor housing, at a location opposite to where the grinding wheel is mounted; a lever adapted to be operated by an operator by hand, the lever having a strip shape and being disposed above both the motor housing and wheel guard; and a switch disposed within the wheel guard and connected to the lever via an opening. The motor can be activated or deactivated by a manipulation to the lever by the operator.
In order to prevent operation mistakes, the electric angle grinder further includes a lock means disposed on the lever. The lock means includes a rotating shaft, an engagement portion and a manipulation portion. The principle of the lock means is that when the lock means is in a locked state, the engagement portion engages with a protrusion of the lever with the aid of an elastic force exerted by a spring, and the operator, thus, cannot operate the lever any more. To activate the motor to initiate the grinding or polishing operation of the grinding wheel, the operator needs to operate, with one hand, the manipulation portion with a force exceeding the elastic force of the spring so as to cause the lock means to rotate and the engagement portion to gradually detach from the protrusion of the lever. After the engagement portion becomes disengaged from the protrusion portion, the operator further needs to push the lever upwards, with the other hand, to switch on the switch. Moreover, in order to prevent a restoring force of the switch from causing the engagement portion of the lock means to re-engage with the protrusion of the lever and thus shutting down the motor, the operator further needs to always press the lever throughout the whole process of the grinding or polishing operation.
As indicated in the foregoing description, although this lock means facilitates mistaken operation prevention, it leads to disadvantages such as increase of the operator's physical workload, reduction of operational efficiency, and possible occurrence of undesirable motor shutdown.
SUMMARY OF THE INVENTION
Accordingly, it is an objective of the present invention to provide an electric angle grinder capable of reducing the operator's physical workload and improving operational efficiency and suitable for use by both left-hand and right-hand operators.
In order to achieve the foregoing objective, one aspect of the present invention provides a working tool which includes: a housing; a working mechanism disposed on a working portion of the housing and configured to grind or polish a workpiece, the working mechanism driven to work by a motor disposed within the housing; a switch disposed within a handle portion of the housing and configured to activate or deactivate the motor; and a lever disposed under the switch and having a first end connected to the housing, wherein the lever has a gap formed therein for accommodating a switch lock, the switch lock having a rotating shaft inserted therethrough, the rotating shaft having two ends both connected to the lever and surrounded by a torsion spring, the switch lock including a first portion extending out of the lever and a second portion hiding in the housing, wherein the second portion of the switch lock has a first engagement portion defined on a first side and a stopper portion defined on a second side thereof, the lever having a support portion proximal to and engageable with the first engagement portion, wherein the handle portion of the housing has a left push button and a right push button partially inserted therein from a left side and a right side, respectively, the left push button and the right push button each having a first end horizontally protruding out of the housing to act as a manipulation portion and a main body and a second end hiding in the housing, the second end of the left push button slidably fitting in the second end of the right push button to allow the left push button to move horizontally towards the right push button and the right push button to move horizontally towards the left push button, the second ends of the left push button and right push button having a reset mechanism interconnected therebetween, wherein the main bodies of the left push button and the right push button in the housing are formed with a first groove and a second groove, respectively, the lever having a first extension section and a second extension section formed at a second end thereof in correspondence with the positions of the first groove and the second groove, respectively, the first extension section and the second extension section extending in the first groove and the second groove, respectively, each of the first groove and the second groove having a second engagement portion formed on a groove wall thereof, each of the first extension section and the second extension section being provided with, at a side facing a corresponding second engagement portion, a third engagement portion engageable with the corresponding second engagement portion, wherein when the working tool is in a locked state, the first engagement portion engages with the support portion, the stopper portion being pushed against a fixation member disposed in the housing, each second engagement portion being disengaged from the corresponding third engagement portion, and wherein when the working tool is in an unlocked state, the first engagement portion is disengaged from the support portion, the stopper portion being apart from the fixation member, the second engagement portion on the first groove engaging with the third engagement portion on the first extension portion or the second engagement portion on the second groove engaging with the third engagement portion on the second extension portion.
Preferably, the second end of the left push button may define third extension sections each formed with a first sliding groove, and the second end of the right push button may define fourth extension sections each formed with a second sliding groove, wherein each of the third extension sections has an end portion horizontally slidably disposed in a corresponding second sliding groove, and each of the fourth extension sections has an end portion horizontally slidably disposed in a corresponding first sliding groove, wherein the end portions of the third extension sections and the end portions of the fourth extension sections are hooked up when the working tool is in a locked state, and the reset mechanism is disposed in a space defined by the third extension sections and the fourth extension sections.
Preferably, the reset mechanism may include a reset spring and a protrusion extending from a central area of the second end of the left push button towards the right push button, wherein the reset spring surrounds the protrusion.
Preferably, the working mechanism may include a grinding wheel and a guard securing means disposed spacedly around the grinding wheel; the grinding wheel may be driven to rotate by the motor, wherein the guard securing means may include a guard disposed around the grinding wheel and a front cover coupled to the housing; the guard may be provided a snap ring axially extending from a surface thereof opposite to the grinding wheel in a direction departing from the grinding wheel; the snap ring may be formed with one or more protrusions on the inner surface, and a top portion of the front cover defines one or more recesses, a number of which is equal to a number of the one or more protrusions; the front cover may define an outer circumstantial surface formed with an annular groove, and the one or more protrusions of the snap ring may fit in the annular groove with an aid of the one or more recesses of the front cover; the snap ring and the front cover may sandwich a portion of a wrench and leave a hanging tongue of the wrench outside; the snap ring may be formed with stop notches, and the portion of the wrench sandwiched between the snap ring and the front cover may be formed with a stop cog engaging with one of the stop notches.
Another aspect of the present invention provides a working tool, which includes: a working mechanism disposed on a working portion of the housing and configured to grind or polish a workpiece, the working mechanism driven to work by a motor disposed within the housing; a switch disposed within a handle portion of the housing and configured to activate or deactivate the motor; and a lever disposed under the switch and having a first end connected to the housing, wherein the lever has a gap formed therein for accommodating a switch lock, the switch lock having a resilient shaft inserted therethrough, the resilient shaft having two ends both connected to the lever and surrounded by a torsion spring, the switch lock including a first portion extending out of the lever and a second portion hiding in the housing, wherein the second portion of the switch lock has a first engagement portion defined thereon, and the lever has a support portion proximal to and engageable with the first engagement portion, wherein the handle portion of the housing has a left push button and a right push button partially inserted therein from a left side and a right side, respectively, the left push button and the right push button each having a first end horizontally protruding out of the housing to act as a manipulation portion and a main body and a second end hiding in the housing, the second end of the left push button slidably fitting in the second end of the right push button to allow the left push button to move horizontally towards the right push button and the right push button to move horizontally towards the left push button, the second ends of the left push button and right push button having a reset mechanism interconnected therebetween, wherein the left push button has a first extension portion extending towards the lever and the right push button has a second extension portion extending towards the lever, the first extension portion having an end portion defining a fourth engagement portion and the second extension portion having an end portion defining a fifth engagement portion, the fourth engagement portion and the fifth engagement portion spacedly disposed opposing each other to form an engagement gap between the first extension portion and the second extension portion, the lever having a fifth extension section extending towards and partially inserted in the engagement gap, the fifth extension section having a sixth engagement portion in the engagement gap and engageable with the fourth engagement portion or the fifth engagement portion, wherein when the working tool is in a locked state, the first engagement portion engages with the support portion, and the sixth engagement portion is disengaged from both of the fourth engagement portion and the fifth engagement portion, and wherein when the working tool is in an unlocked state, the first engagement portion is disengaged from the support portion, and the sixth engagement portion engages with the fourth engagement portion or the fifth engagement portion.
Preferably, the housing and the lever may have a handle reinforcement plate formed therebetween and the handle reinforcement plate may be fixedly coupled to the lever.
Advantageously, the working tool of the present invention entails an electric angle grinder that can be locked to reduce operation mistakes as much as possible by employing a simple structure. Also advantageously, the electric angle grinder can be maintained in an unlocked state throughout an operation process without needing an operator to always press the lever, thereby reducing the operator's physical workload, improving operational efficiency, and preventing inadvertent shutdown of the motor. Still also advantageously, the design of the left and right push buttons allows any operator, no matter left-handed or right-handed, to operate the tool conveniently.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a partial schematic cross-sectional view illustrating a working tool in a locked state in accordance with Embodiment 1 of the present invention.
FIG. 1B is an enlarged view of part of FIG. 1A .
FIG. 2 is a cross-sectional view taken along line B-B of FIG. 1A .
FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2 .
FIG. 4 depicts a partial schematic cross-sectional view illustrating a working tool of Embodiment 1 after a switch lock is turned counterclockwise.
FIG. 5 depicts a partial schematic cross-sectional view illustrating a working tool of Embodiment 1 after a lever is pressed down.
FIG. 6 is a cross-sectional view taken along line B-B of FIG. 5 .
FIG. 7 is a transverse cross-sectional view of FIG. 6 .
FIG. 8 depicts FIG. 6 after a right push button is pressed down;
FIG. 9 is a transverse cross-sectional view of FIG. 8 .
FIG. 10 is a cross-sectional view of a right push button of the working tool of Embodiment 1 in an unlocked state.
FIG. 11 is a cross-sectional view taken along line A-A of FIG. 10 .
FIG. 12A is an exploded view of a guard securing means in accordance with the present invention.
FIG. 12B is a diagram illustrating the guard securing means in accordance with the present invention after it is assembled.
FIG. 13A schematically illustrates how the guard securing means in accordance with the present invention is assembled.
FIG. 13B depicts a guard having a snap ring formed thereon in accordance with the present invention.
FIG. 13C depicts a front cover of the guard securing means in accordance with the present invention.
FIG. 14A depicts the guard securing means in a secured state in accordance with the present invention.
FIG. 14B is a top view of FIG. 14A in accordance with the present invention.
FIG. 14C schematically illustrates how the orientation of the guard of the guard securing means is adjusted.
FIG. 14D is a top view of FIG. 14C .
FIG. 15 depicts how the guard securing means in accordance with the present invention is disassembled.
FIG. 16 is a partial schematic cross-sectional view illustrating a working tool in a locked state in accordance with Embodiment 2 of the present invention.
FIG. 17 is a cross-sectional view taken along line B-B of FIG. 16 .
FIG. 18 is a cross-sectional view taken along line A-A of FIG. 17 .
FIG. 19 depicts FIG. 17 and FIG. 18 after a lever moves upwards.
FIG. 20 is a cross-sectional view taken along line A-A of FIG. 19 .
FIG. 21 is an enlarged view of part I of FIG. 20 .
FIG. 22 depicts FIG. 17 and FIG. 18 after a right push button is pushed inwardly.
FIG. 23 is a cross-sectional view taken along line A-A of FIG. 22 .
FIG. 24 is an enlarged view of part II of FIG. 23 .
FIG. 25 depicts FIG. 17 and FIG. 18 after the engagement between engagement portions.
FIG. 26 is a cross-sectional view taken along line A-A of FIG. 25 .
FIG. 27 is an enlarged view of part III of FIG. 26 .
DETAILED DESCRIPTION
The present invention will become more readily apparent and better understood as the following detailed description of preferred embodiments of the invention is considered in connection with the accompanying drawings.
Embodiment 1
Referring now to FIGS. 1A and 1B , the present embodiment discloses a working tool including a housing 10 . A working mechanism 11 is disposed on a working portion of the housing 10 and configured to grind or polish a workpiece. In this embodiment, the working portion is located at the left end of the housing 10 . The working mechanism 11 is driven to work by a motor disposed within the housing 10 . A switch 9 is disposed within a handle portion of the housing 10 . In this embodiment, the handle portion is located at the right end of the housing 10 . The switch 9 is configured to activate or deactivate the motor. When the motor is activated, the working mechanism 11 is driven to grind or polish; or when the motor is deactivated, the working mechanism 11 stops its operation. A lever 3 is disposed under the switch 9 and has its left end connected to the housing 10 . When an operator presses down the lever 3 , the motor is activated. The lever 3 has a gap formed therein for accommodating a switch lock 1 , and the switch lock is disposed in this gap. The switch lock 1 has a rotating shaft inserted through a middle portion thereof and the rotating shaft has its two ends both connected to the lever 3 , thereby allowing the switch lock 1 to rotate about the rotating shaft. The rotating shaft is surrounded by a torsion spring 2 . The switch lock 1 includes a first portion extending out of the lever 3 and a second portion hiding in the housing 10 . The second portion of the switch lock 1 has a first engagement portion 1 a extending outwardly on a right side thereof and a stopper portion 1 b extending upwardly on a left side thereof. The lever 3 has a support portion 3 a proximal to and engageable with the first engagement portion 1 a . With further reference to FIG. 2 , the handle portion of the housing 10 is provided with a left push button 8 and a right push button 5 partially inserted therein from the left and right sides, respectively. The left push button 8 and the right push button 5 each has a first end horizontally protruding out of the housing 10 to act as a manipulation portion and a rest portion including a main body and a second end hiding in the housing 10 . The second end of the left push button 8 slidably fits in the second end of the right push button 5 , thereby allowing the left push button 8 to move horizontally towards the right push button 5 and the right push button 5 to move horizontally towards the left push button 8 .
In the present embodiment, the fitting between the second ends of the left and right push buttons may be accomplished by the following design. The second end of the left push button 8 defines third extension sections 8 b each extending towards the right push button 5 and has a first sliding groove formed thereon. Similarly, the second end of the right push button 5 defines fourth extension sections 5 b each extending towards the left push button 8 and has a second sliding groove formed thereon. Each of the third extension sections 8 b has an end portion horizontally slidably disposed in a corresponding first sliding groove, and each of the fourth extension sections 5 b has an end portion horizontally slidably disposed in a corresponding second sliding groove. The end portions of the third and fourth extension sections 8 b , 5 b can be hooked up when the working tool is in a locked state.
A reset mechanism is interconnected between the second ends of the left push button 8 and the right push button 5 . As illustrated, the reset mechanism may be disposed in a space defined by the third extension sections 8 b and fourth extension sections 5 b . In the present embodiment, the reset mechanism includes: a reset spring 6 and a protrusion 12 extending from a central area of the second end of the left push button 8 towards the right push button 5 , wherein the reset spring 6 surrounds the protrusion 12 .
The main bodies of the left push button 8 and the right push button 5 in the housing 10 are formed with a first groove 8 a and a second groove 5 a , respectively. Correspondingly, the lever 3 has a first extension section 3 a - 2 and a second extension section 3 a - 1 formed at its right end in correspondence with the positions of the first and second grooves 8 a and 5 a , respectively. The first extension section 3 a - 2 and the second extension section 3 a - 1 extend in the first groove 8 a and the second groove 5 a , respectively. The first groove 8 a has a second left engagement portion 8 c formed on its groove wall and the second groove 5 a has a second right engagement portion 5 c formed on its groove wall. The first extension section 3 a - 2 is provided with, at a side facing the second left engagement portion 8 c , a third left engagement portion 3 b - 1 engageable with the second left engagement portion 8 c ; and the second extension section 3 a - 1 is provided with, at a side facing the second right engagement portion 5 c , a third right engagement portion 3 b - 2 engageable with the second right engagement portion 5 c.
The working mechanism 11 of the present embodiment may include a grinding wheel 14 and a guard securing means 13 disposed spacedly around the grinding wheel 14 . The grinding wheel 14 can be driven to rotate by the motor.
Referring now to FIGS. 12A and 12B , the guard securing means 13 may include a guard 13 - 1 disposed around the grinding wheel 14 and a front cover 13 - 6 coupled to the housing 10 . The guard 13 - 1 is provided with a snap ring 13 - 2 axially extending from a surface of the guard 13 - 1 opposite to the grinding wheel 14 in a direction departing from the grinding wheel 14 . The snap ring 13 - 2 is formed with protrusions e 1 , e 2 , e 3 , e 4 , and e 5 on the inner surface. Correspondingly, a top portion of the front cover 13 - 6 defines recesses g 1 , g 2 , g 3 , g 4 , and g 5 for engaging with the respective protrusions. The front cover 13 - 6 defines an outer circumstantial surface formed with an annular groove 13 - f , and the annular groove 13 - f is also engageable with the protrusions. The snap ring 13 - 2 and the front cover 13 - 6 sandwich and fix a portion of a wrench 13 - 5 using an upper fixation plate 13 - 3 and screws 13 - 4 and leave a hanging tongue of the wrench 13 - 5 outside. The snap ring 13 - 2 is formed with stop notches 13 - b , and the wrench 13 - 5 is formed with a stop cog 13 - a for engaging with one of the stop notches 13 - b . A spring 13 - 7 is disposed between the wrench 13 - 5 and an outer circumstantial surface of the front cover 13 - 6 . The guard 13 - 1 and the snap ring 13 - 2 are integrated as a whole 13 - 8 by welding.
Referring to FIGS. 13A to 13C , the assembly of the guard can be accomplished by following the steps of: pushing down the wrench 13 - 5 ; aligning the protrusions e 1 , e 2 , e 3 , e 4 , and e 5 of the snap ring 13 - 2 with the corresponding recesses g 1 , g 2 , g 3 , g 4 , and g 5 of the front cover 13 - 6 and fitting the guard to the front cover 13 - 6 ; rotating the guard until the protrusions of the snap ring 13 - 2 are received in the annular groove 13 - f of the front cover 13 - 6 ; further rotating the guard to a desired position; and releasing the wrench 13 - 5 such that the stop cog 13 - a of the wrench 13 - 5 is inserted into a corresponding stop notch 13 - b of the snap ring 13 - 2 , thereby preventing further rotation of the guard and finishing the assembly of the guard of the grinding wheel.
Referring to FIGS. 14A to 14D , the securing and orientation adjustment of the guard can be accomplished by following the steps of: pushing the wrench 13 - 5 to make it slide along a sliding channel formed by a counter groove 13 - c of the front cover 13 - 6 and the upper fixation plate 13 - 3 (which is fixed to the front cover 13 - 6 using the screws 13 - 4 ), until the stop cog 13 - a of the wrench 13 - 5 becomes disengaged from the corresponding stop notch 13 - b of the snap ring 13 - 2 (refer to t 1 of FIG. 14D ); rotating the guard 13 - 1 until it is oriented at a desired angle; and after the guard 13 - 1 is adjusted in place, releasing the wrench 13 - 5 , so that the spring 13 - 7 will exert an elastic force which pushes the stop cog 13 - a into the corresponding stop notch 13 - b (refer to t 2 of FIG. 14B ), thereby positioning the guard 13 - 1 and preventing its further rotation.
Referring to FIG. 15 , the guard can be detached by pressing down the wrench 13 - 5 , rotating the guard 13 - 1 to a position corresponding to the front cover 13 - 6 , taking the guard 13 - 1 out, and releasing the wrench 13 - 5 .
Referring back to FIG. 1B , when the working tool is in a locked state, the first engagement portion 1 a firmly engages with the support portion 3 a with the aid of the torsion spring 2 , and the stopper portion 1 b is pushed tightly against a fixation member 10 a disposed in the housing 10 . As such, an operator is unable to operate the lever 3 . Moreover, with further reference to both FIG. 2 and FIG. 3 , the end portions of the third and fourth extension sections 5 b , 8 b are hooked up, with the second left engagement portion 8 c being disengaged from the third left engagement portion 3 b - 1 and the second right engagement portion 5 c being disengaged from the third right engagement portion 3 b - 2 .
When to unlock the working tool, an operator needs to first rotate the switch 1 in the counterclockwise direction (as indicated by the arrow in FIG. 4 ) with one hand to disengage the first engagement portion 1 a from the support portion 3 a , accompanied with the departure of the stopper portion 1 b from the fixation member 10 a . Generally, the left hand is used for a right-handed operator, and the right hand is used for a left-handed operator.
Next, the operator further needs to press the lever 3 in the direction as indicated by the arrow in FIG. 5 with the other hand. Generally, the right hand is used for the right-handed operator, and the left hand is used for the left-handed operator. As such, with further reference to both FIG. 6 and FIG. 7 , the first extension section 3 a - 1 and second extension section 3 a - 2 move upwards with the lever 3 , thus causing the third left engagement portion 3 b - 1 and the third right engagement portion 3 b - 2 to move and stay over the second left engagement portion 8 c and the second right engagement portion 5 c , respectively. Then, after the left-handed operator pushes, with the thumb of the left hand, the right push button 5 towards the left push button 8 in the direction as indicated by the arrow in FIG. 8 , with further reference to FIG. 9 , the second right engagement portion 5 c will move and stay right under the third right engagement portion 3 b - 2 . As such, after the operator releases the lever 3 , which is accompanied with the downward movement of the third right engagement portion 3 b - 2 and thereafter its engagement with the second right engagement portion 5 c as shown in FIG. 10 and FIG. 11 , the working tool will maintain an unlocked state without needing the operator to continuously press the lever 3 to keep the working tool in an operational state. It is to be understood that the right-handed operator can also make the working tool maintained in the unlocked state by pushing the left push button 8 towards the right push button 5 with the thumb of the right hand and then following the same subsequent steps, the detailed description of which is omitted for the sake of simplicity.
Furthermore, the operator can shut down the working tool, simply by pushing the lever 3 upwards to cause the third left engagement portion 3 b - 1 or the third right engagement portion 3 b - 2 to move upwards with the lever and thus become disengaged from the corresponding second left engagement portion 8 c or second right engagement portion 5 c . After this occurs, affected by the reset spring 6 , the second left engagement portion 8 c or the second right engagement portion 5 c will be pushed and no longer stay right under the corresponding third left engagement portion 3 b - 1 or third right engagement portion 3 b - 2 . As such, after the operator releases the lever 3 , the lever 3 will return to the original position with the aid of the torsion spring 2 , the first engagement portions 1 a will again engage with the support portion 3 a , and the stopper portion 1 b will be pushed against the fixation member 10 a , thereby locking the working tool again.
Embodiment 2
As illustrated in FIG. 16 , the present embodiment provides a working tool including a housing 10 . A working mechanism 11 is disposed on a working portion of the housing 10 and configured to grind or polish a workpiece. The working mechanism 11 is driven to work by a motor disposed within the housing 10 . A switch 9 for activating or deactivating the motor is disposed within a handle portion of the housing 10 . A lever 3 is disposed under the switch 9 and has one end connected to the housing 10 . The lever 3 has a gap formed therein for accommodating a switch lock 1 , and the switch lock is disposed in this gap. A resilient shaft is inserted through the switch lock 1 and has its two ends both connected to the lever 3 . The resilient shaft is surrounded by a torsion spring 2 . The switch lock 1 includes a first portion extending out of the lever 3 and a second portion hiding in the housing 10 . The second portion of the housing 10 has a first engagement portion defined thereon, and the lever 3 has a support portion 3 a proximal to and engageable with the first engagement portion 1 a . With additional reference to FIGS. 17 and 18 , the handle portion of the housing 10 is provided with a left push button 8 and a right push button 5 partially inserted therein from the left side and right side, respectively. The left push button 8 and the right push button 5 each has a first end horizontally protruding out of the housing 10 to act as a manipulation portion and a rest portion including a main body and a second end hiding in the housing 10 . The second end of the left push button 8 slidably fits in the second end of the right push button 5 , thereby allowing the left push button 8 to move horizontally towards the right push button 5 and the right push button 5 to move horizontally towards the left push button 8 . A reset mechanism is interconnected between the second ends of the left push button 8 and right push button 5 . The left push button 8 has a first extension portion 8 d extending towards the lever 3 and the right push button 5 has a second extension portion 5 d extending towards the lever 3 . The first extension portion 8 d has an end portion defining a fourth engagement portion 8 d - 1 , and the second extension portion 5 d has an end portion defining a fifth engagement portion 5 d - 1 . The fourth engagement portion 8 d - 1 and the fifth engagement portion 5 d - 1 are spacedly disposed opposing each other to form an engagement gap 15 between the first extension portion 8 d and the second extension portion 5 d . The lever 3 has a fifth extension section 3 c extending towards and partially inserted in the engagement gap 15 . The fifth extension section 3 c has a sixth engagement portion 3 c - 1 in the engagement gap 15 and engageable with the fourth engagement portion 8 d - 1 or the fifth engagement portion 5 d - 1 .
Referring back to FIG. 1 , when the working tool is in a locked state, the sixth engagement portion 3 c - 1 is disengaged from both of the fourth engagement portion 8 d - 1 and the fifth engagement portion 5 d - 1 .
As shown in FIGS. 19 to 21 , when to unlock the working tool, an operator needs to first push the lever 3 upwards to cause the sixth engagement portion 3 c - 1 to move and stay over the fourth engagement portion 8 d - 1 and the fifth engagement portion 5 d - 1 . Next, with further reference to FIGS. 22 to 24 , the operator further needs to inwardly push the right push button 5 or the left push button 8 to cause the fourth engagement portion 8 d - 1 or the fifth engagement portion 5 d - 1 to move towards and stop right under the sixth engagement portion 3 c - 1 . As such, with further reference to FIGS. 25 to 27 , after the operator releases the lever 3 , the sixth engagement portion 3 c - 1 moves downwards and engages with the fourth engagement portion 8 d - 1 or the fifth engagement portion 5 d - 1 .
The rest of this embodiment has the same structure and works in the same way as that described in Embodiment 1. | A working tool includes a housing ( 10 ) and a lever ( 3 ) having a gap defined therein for accommodating a rotatable switch lock ( 1 ). The switch lock has a first engagement portion ( 1 a ) defined on a first side and a stopper portion ( 1 b ) defined on a second side, and the lever has a support portion ( 3 a ) proximal to the first engagement portion. A handle portion of the housing has a left push button ( 8 ) and a right push button ( 5 ) inserted therein, a first groove ( 8 a ) and a second groove ( 8 b ) of the left push button ( 8 ) and right push button ( 5 ) each having a second engagement portion formed on a groove wall thereof, each of a first extension section ( 3 a - 2 ) and second extension sections ( 3 a - 1 ) being provided with, at a side facing a corresponding second engagement portion, a third engagement portion engageable with the corresponding second engagement portion. The working tool is capable of reducing operation mistakes as much as possible, preventing inadvertent shutdown of the motor, and allowing any operator, no matter left-handed or right-handed, to operate it conveniently. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to surface protective coatings and more specifically to anti-mold, anti-graffiti coatings that also protect the substrate from the surface-degrading effects of moisture, oxygen, ozone and ultra-violet radiation, and that often enhance the color and luster of newer items, and often restore the color and luster on older, weathered items. These coatings withstand temperatures in excess of 300 degrees Fahrenheit without blistering, cracking, peeling or yellowing. The enhanced leveling properties of these coatings are such that, even when applied by brush or roller, they cure to an essentially mirror-smooth final film. The preferred embodiments of this invention that do not comprise fillers and/or hiding agents are easily removed from the substrate using a mild organic solvent, including but not limited to, denatured alcohol and isopropanol. These coatings are appropriate for use on a multitude of different substrate types.
BACKGROUND OF THE INVENTION
[0002] The surfaces of many materials and items are susceptible to weathering and breakdown due to one or more of the following: oxygen, ozone, moisture, UV radiation, and/or attack from various types of microorganisms. The resultant surface and structural degradation usually takes the form of either corrosion (oxidation, including rusting), bleaching, chalking, dry rot, cracking, blistering, peeling, yellowing or water damage. Restoration is traditionally along the line of costly and labor-intensive repair or replacement.
[0003] The present invention offers a simple and cost-effective alternative. The films formed by the preferred embodiments of the present invention form a flexible, durable, resilient, and air, moisture and UV-resistant barrier that also inhibits microorganism infestation, and they maintain their structural integrity to temperatures up to, and potentially in excess of, 300 degrees Fahrenheit. Consequently, application of the present invention to surfaces before serious degradation has occurred will significantly extend the longevity of said surfaces. Also, the preferred embodiments that cure to a clear and colorless final film have the added benefit of partially-to-fully restoring the color and luster on older, weathered surfaces, and enhancing the color and luster on newer surfaces.
[0004] U.S. Pat. No. 4,184,991 describes an invention that is a corrosion inhibitor for use on ferrous metal substrates, and is based on benzotriazoles, tolytriazoles, substituted benzotriazoles and substituted tolytriazoles, all of which are well known corrosion inhibitors. The limitation of the composition disclosed in this patent, relative to the present invention, is that it is limited to this single type of application.
[0005] U.S. Pat. No. 4,581,090 describes a two part system comprising an adhesive material, such as a varnish, and a granular material, such as sand, onto an imperfect or weathered surface such as a vinyl roof top, roofing material, and siding and building structures. The purpose of this invention is to recondition the surface for long life, and to produce a like-new appearance. The invention described in this patent is more cost and labor-intensive to apply than the present invention, requiring a separate reservoir and a compressed air means to apply the granular material, and requiring that the adhesive material and the granular material be applied to the substrate in multiple and alternating layers. Also, the final finish obtained has a rough texture versus the present invention, which produces a smooth, satin-to-shiny final film. Another limitation of the invention disclosed in this patent, relative to the present invention, is that it is limited to these few types of applications.
[0006] U.S. Pat. No. 4,274,933 describes a restorative-type invention for use on organic glass plates, light fixture covers, optical lenses, eyeglass lenses, mirrors, etc., to repair scratches on said items. These are not intended uses of the present invention.
[0007] U.S. Pat. No. 4,759,955 describes an invention for the purpose of enhancing and renovating the appearance of vinyl fabrics and coverings. Vinyl items exposed to sunlight and the elements tend to oxidize, causing them to loose color and luster, and become chalky. This composition is also able to fill small cracks and openings, thus preventing moisture and other materials from passing through. A disadvantage of the invention described in this patent is that it comprises toluene, which is both environmentally and user-unfriendly. Another limitation of the composition disclosed in this patent, relative to the present invention, is that it is limited to this single type of application.
[0008] The invention described in U.S. Pat. No. 4,133,913 relates to a method for repairing cracks, cuts and other imperfections in plastic materials, and more specifically, on automobile dashboards and the like. The invention is capable of providing a textured finish, as necessary, in order to match the surface to which it is applied. The invention described in this patent is more labor-intensive than the present invention, requiring the application of three separate components: a filler, an acrylic resin lacquer, and a textured acrylic resin coating. In addition, a sanding step is required between application of the filler and the acrylic resin lacquer. Another limitation of the invention disclosed in this patent, relative to the present invention, is that it is limited to this single type of application.
[0009] U.S. Pat. No. 5,332,431 describes an antifouling (anti-microorganism) paint specific to marine applications and based on organocopper and organotin active ingredients. This patent application also cites three other antifouling coating compositions for aquatic use, described in patent application numbers 59344/90, 224452/62 and 127025/91 (all three are Japanese applications). The limitation of the inventions described in these three patents, according to the present inventor of U.S. Pat. No. 5,332,431, is that the active ingredient(s) are very water soluble, so are easily leached out of the coatings. This has harmful effects on the surrounding environment, and significantly shortens the life-span of the antifouling properties. Marine applications are not necessarily intended uses of the present invention.
[0010] The antifouling paint for marine use described in U.S. Pat. No. 5,332,431 claims to have overcome the above-mentioned leaching problems using an active compound consisting essentially of an alkylphenoxy group containing an organo silicon compound. Marine applications are not necessarily intended uses of the present invention.
[0011] U.S. Pat. No. 5,332,431 describes an anti-microorganism agent comprising various metal hydroxides. A disadvantage of this type of anti-mold agent, relative to the present invention, is that it imparts a white discoloration to the final film. Three of the preferred embodiments of the present invention form a clear and colorless final film, so any discoloration imparted by the anti-microorganism agent (or any other additive) would produce an aesthetically undesirable final result.
[0012] U.S. Pat. No. 5,332,431 states that some commercially available anti-mold agents tend to degrade the heat resistance and weatherability properties of coating compositions. Such is not the case with the anti-microorganism additive incorporated in the present invention.
[0013] All of the preferred embodiments of the present invention form surface-protective barriers that inhibit the substrate-degrading effects of oxygen, ozone, UV-radiation, dry rot and moisture. The films formed by these coating compositions inhibit corrosion (including rust), oxidation, bleaching, chalking, weathering, blistering, peeling, cracking, yellowing, water damage, and dry rot. They are anti-mold. They enhance the color and luster on newer substrates, and partially-to-fully restore the color and luster on older, weathered substrates. They are applicable to a multitude of different articles and substrate types.
[0014] Graffiti is an on-going and, especially in many urban areas, an often ubiquitous problem. This unsightly form of vandalism is especially pervasive on concrete structures, bridges, walls of buildings, buses, subway cars, trucks, and railroad box cars. The most common modes of application are flexible-tip permanent marking pens and canned spray paints that are typically oil-based. Millions of dollars are spent annually to remove or obliterate the graffiti and to restore the underlying surface.
[0015] One cost-effective method of dealing with graffiti problems is to apply a protective coating to the substrate which acts as a sacrificial film that prevents the migration of the graffiti through the film and allows for removal of the graffiti. Traditional alternative means of dealing with graffiti include painting over the graffiti, or performing a combination of: applying a paint remover such as methylene chloride, toluene or benzene, followed by power washing, followed by sand blasting or sanding. Scraping, hydro-sanding and hydro-blasting are also viable alternatives. All of these traditional alternative methods are more expensive and more labor-intensive. In addition, the means involving the use of organic solvents results in the release of harmful organic vapors which are detrimental to health, and the environment. Also, use of these relatively strong solvents, and sandblasting or sanding, may have a negative impact on both the structural integrity and aesthetics of the substrate. Also, all of the mechanical means have been found to etch and score, and therefore, make the surface porous and rough. Consequently, the surface is more susceptible to weathering, general deterioration and permanent staining. Sandblasting also often emits potentially carcinogenic and siliceous particles into the air.
[0016] Chemical methods for removing graffiti from both painted and unpainted surfaces involve the use of strong acids, strong bases, or volatile organic compound-type solvents. However, these methods are now being restricted because they are environmentally hazardous and pose a safety risk to the user. Also, repeated use tends to degrade several substrate types.
[0017] U.S. Pat. No. 4,241,141 describes a removable anti-graffiti coating. However, this invention requires special cleaning solutions to remove it. U.S. Pat. No. 6,187,851 describes a coating composition in which the graffiti can be removed either alone or with the anti-graffiti film. However, the recommended cleaning or film removing solvents include esters or ketones, such as acetone, methylethylketone, and ethyl acetate, which are harmful to both the user and the environment. U.S. Pat. No. 5,387,434 discloses another removable anti-graffiti coating. However, this coating requires power washing using pressures in excess of 250 psi, and preferably in excess of 1000 psi, and water temperatures between 120 and 194 degrees Fahrenheit to remove the coating. U.S. Pat. No. 5,750,269 describes another removable anti-graffiti coating. However, the films formed by this invention require the use of hot water or steam, in the form of a spray or jet, to remove the coating. The equipment required to remove the coatings formed by these later two inventions is expensive, cumbersome, and will require gasoline or a source of electricity to power said equipment.
[0018] U.S. Pat. No. 6,974,605 describes non-sacrificial anti-graffiti coating compositions. However, a special cleaner comprising N-pyrrolidone and a surfactant is required to effectively remove marker and spray paint-type graffiti from the films formed by these compositions. Also, the composition comprising water-based epoxy contains ether, which is both environmentally and user-unfriendly, and forms a film that is clear but is slightly yellow, rendering it aesthetically unsuitable for some applications. Also, the composition comprising aliphatic urethane contains a volatile organic compounds content that exceeds the mandated environmentally safe levels in some states, and so may be unsuitable for use in these areas.
[0019] U.S. Pat. No. 7,247,671 also describes a non-sacrificial coating invention. The recommended solvent for removing permanent marker-type graffiti is methyl ethyl ketone which, as described previously, is harmful to both the user and the environment.
[0020] U.S. Pat. No. 5,376,705 also describes a non-sacrificial invention that comprises a two part system that must be premixed prior to application, and thus is not as convenient to use as a one component system. This invention also requires the use of special non-abrasive, non-acidic, non-caustic graffiti cleaners, such as described in U.S. Pat. No. 5,024,780. Some preferred embodiments contain toluene and xylene, which are both environmentally and user-unfriendly.
[0021] U.S. Pat. No. 5,910,535 describes a sacrificial-type anti-graffiti coating that can be effectively removed from the substrate using soap and water. However, all of these inventions are paint-type coatings; they form opaque films that effectively hide the substrate. The anti-graffiti preferred embodiments of the present invention form clear and colorless final films.
[0022] The anti-graffiti preferred embodiments of the present invention form clear and colorless final films that may be cleaned with a cloth moistened with water or a mild soap and water solution. If these means prove insufficient to effectively remove graffiti from the surface of the film, the graffiti and the coating itself may be effectively removed using a relatively mild, and user and environmentally-safe organic solvent such as ethanol, isopropanol, or denatured alcohol. These anti-graffiti preferred embodiments are suitable for use on a multitude of different articles and substrate types.
[0023] Films formed by latex paints are usually not entirely smooth, but often contain surface characteristics referred to as waviness and orange peel. Waviness is typical of brush application and orange peel is indicative of either roller or spray application. More often than not, these surface textures are unwanted, and detract from the aesthetics of the final finish. The degree to which surface structure is formed (i.e. no structural features versus fine structural features versus course structural features) depends on the nature of the composition, and is most affected by the types and relative proportions of: solvents, rheology modifiers (flow and leveling agents), fillers, pigments, hiding agents, defoamers, and surfactants.
[0024] A preferred embodiment of the present invention is a latex paint-type composition with enhanced leveling properties, such that, when applied to a smooth substrate with no surface texture, the final film formed by said latex paint-type preferred embodiment has an essentially mirror-like final finish, regardless of how the composition is applied (i.e. by brush, sprayer or roller). When applied to a substrate with surface features and/or textures, said features and textures will be imparted to the final, cured paint film.
[0025] U.S. Pat. No. 4,148,948 describes a water-dispersible paint of improved leveling characteristics comprising a substantial proportion of water. This composition is designed for fast, high temperature cures. This invention is only for use on plastic and metal articles, such as cans, and is applied to said cans using an expensive industrial-type, automated roller system. The present invention is suitable for use on a multitude of different substrate types, and using several modes of application, including rolling, brushing and spraying.
[0026] U.S. Pat. No. 4,522,986 relates to high solids urethane paint systems comprising urea flow control agents, said flow control agents added for the combined purposes of reducing sag while still promoting excellent leveling properties. This invention is sprayable and is used in automotive applications. The present invention has not necessarily been designed for automotive applications.
[0027] U.S. Pat. No. 4,703,080 describes a latex paint with enhanced leveling properties. This document mentions application of said paint composition by brush only, and does not cite any substrate or item types to which the invention is applicable.
[0028] Several patents were found that claim the leveling agent itself, and not an actual paint composition. U.S. Pat. No. 5,605,966 describes a leveling agent in the form of a microcapsule for use in heat-cured powder coatings. U.S. Pat. No. 7,230,051 relates to the use of block copolymers as leveling agents. U.S. Pat. No. 6,630,522 describes flow and leveling agents for paints and inks. U.S. Pat. No. 6,121,439 describes a water-soluble polysaccharide leveling agent for waterborne paints. U.S. Pat. No. 6,660,828 describes a polymer-type flow and leveling agent containing fluoro groups for use in waxes, polishes and coatings.
[0029] Two patents were found that claim a binder that enhances the flow and leveling properties of any paint system into which it is incorporated. In both, again, an actual paint composition is not claimed. These patents are: U.S. Pat. No. 5,182,327 and U.S. Pat. No. 5,256,724.
[0030] U.S. Pat. No. 7,399,350 relates to latex paint and printing ink compositions. None of the preferred embodiments of the present invention are printing ink compositions. The paint compositions described owe their enhanced leveling properties to the addition of disiloxane surfactant-type flow and leveling agents. The present invention comprises a polyurethane-based flow and leveling agent. A limitation of the composition described in U.S. Pat. No. 7,399,350 is that some preferred embodiments comprise aromatic solvents and ketones, both of which are environmental and user-unfriendly. The present invention does not comprise harmful or toxic constituents.
SUMMARY OF THE INVENTION
[0031] An object of the present invention is to provide anti-graffiti coating compositions which can be applied to protect painted and unpainted surfaces of all types from graffiti and other markings.
[0032] Another object of the present invention is to provide anti-graffiti, anti-mold coating compositions that have enhanced leveling properties, can withstand temperatures in excess of 300 degrees Fahrenheit without cracking, peeling, blistering or yellowing, often partially-to-fully restore the color and luster on older, weathered substrates and often enhance the color and luster on newer substrates, have enhanced leveling properties, and protect the substrate from the surface-degrading effects of moisture, UV-radiation, oxygen, and ozone, which are inexpensive to manufacture and environmentally-friendly and worker-safe to use, thereby requiring minimal protective clothing and respiratory equipment, said coatings having negligible volatile organic content.
[0033] A further object of the present invention is to provide anti-graffiti coating compositions which, when applied to a surface, form a graffiti barrier to render the surface substantially resistant to penetration by subsequent applications of graffiti and which can be easily removed using a mild, environmentally safe, and safe to use organic solvent, including but not limited to, denatured alcohol and isopropanol.
[0034] Another object of the present invention is to provide a method of protecting surfaces from graffiti by applying an anti-graffiti coating to the surfaces and, when needed, removing the coating in order to remove the graffiti and then reapplying a fresh anti-graffiti coating.
[0035] Another object of the present invention is to provide airtight, water proof and UV-resistant coating compositions that will protect the substrate from oxidation, corrosion (including rusting), water damage, dry rot, bleaching, chalking, cracking, peeling, yellowing, and microorganism infestation.
[0036] Another object of this invention is to provide water-based coatings that have anti-microorganism (antifouling) properties, and which have a high anti-microorganism effect when applied to all of the recommended substrates. In order to achieve the desired efficacy, the microbicide additive must achieve excellent dispersibility in the final cured film.
[0037] Another object of this invention is to provide preferred embodiments that are clear and colorless, and partially-to-fully restore the color and luster on older, weathered substrates, and enhance the color and luster on newer, relatively unweathered substrates.
[0038] Another object of this invention is to provide coating compositions that offer enhanced leveling efficiencies, such that, regardless of the mode of application employed (including brushing and rolling), an essentially mirror-smooth final film is achieved on all of the recommended substrates, provided that said substrate itself has a mirror-smooth surface.
[0039] Another object of this invention is to provide coating compositions that form films that will not blister, peel, crack, yellow or display any other signs of visible deterioration at all temperatures up to, and potentially in excess of, 300 degrees Fahrenheit.
[0040] The above and other objects of the present invention are accomplished using anti-mold, anti-graffiti compositions comprised of (a) polymer latex resin, (b) water, and (c) a plurality of additives. The member (a) is present in the compositions in an amount of from between 0.1 to 99.9% by volume and at an amount sufficient to form an anti-mold and anti-graffiti barrier on the surface to which it is applied. Any graffiti subsequently applied to the surface is prevented, by the anti-graffiti film barrier formed, from directly coming in contact with the substrate, and can be effectively removed, along with the film, as necessary, using a mild organic solvent such as denatured alcohol or rubbing alcohol. A fresh anti-graffiti coating can then be reapplied, as desired, to the clean substrate.
[0041] These coating and sealing compositions are for the purpose of restoring, renovating, protecting and enhancing the appearance of a multitude of different substrate types and objects, including but not limited to, vinyl, leather, latex and oil-based paints, metal, bare wood, stained or painted wood, lacquered or varnished wood, veneer, plastic, rubber, grout, caulking, concrete, brick, stone, stucco, fiberglass, ceramic tile, etc. Consequently, these compositions represent a considerable cost savings to the user by minimizing the necessity of repairs or replacement.
[0042] These compositions comprise polymer latex resin (binder), solvent, defoamer, surfactant, pigments, substrate-hiding agent, rheology modifiers, matting agent, anti-microorganism agent (microbicide), coalescing agent, binder dispersing agent, and pigment dispersing agent. As the solvent evaporates, the polymer resin and additives form a smooth, airtight and waterproof film that is flexible, resilient, and durable. The coating serves as a protective layer that tends to prevent rapid degradation of the enhanced appearance over a relatively long period of time.
[0043] The coating protects the substrate against mold, mildew and moss growth. The films formed by these compositions also inhibit corrosion (including rust), weathering, bleaching, fading, dry rot, and water damage. These compositions may be applied to substrates that get hot during normal use, such as automotive surfaces, because they will maintain their structural integrity to temperatures up to, and possibly in excess of, 300 degrees Fahrenheit. They protect the substrate from cosmetic damage due to accidental spills, food stains, dirt, and graffiti. Most types of cosmetic damage are effectively removed from the film using a cloth dampened with water or a mild detergent solution. If the stain can not be removed from the film, the film itself can be effectively removed from the substrate using a mild organic solvent such as denatured alcohol or isopropanol. The substrate can then be recoated with the present invention.
[0044] As far as the present inventor is aware, there are no prior art coating compositions that have the combined attributes of substrate color and luster enhancement and/or restoration, anti-mold, enhanced leveling efficiency, anti-graffiti properties, the ability to significantly extend the life of the substrate, cure in 10-20 minutes, are amenable to spray application and withstand temperatures in excess of 300 degrees Fahrenheit with no discernable degradation of any kind. Conventional clear-film-forming products such as varnishes and lacquers, and conventional paints, do not encompass all of the above-mentioned attributes.
[0045] U.S. Pat. No. 4,274,933 discloses the fact that the films formed by many acrylic polymer resin compositions readily become clouded when subjected to moisture. Such is not the case for the preferred embodiments of this invention.
[0046] Many polymer resin-based coating compositions comprise flammable and/or toxic organic solvents. Such is not the case for the preferred embodiments of this invention. Water is the primary solvent in this system. Only trace amounts of organic solvents are present in the polymer resin concentrates and the various additive concentrates.
[0047] When the present invention is applied to older, weathered substrates, the original appearance is virtually restored, enhancing its overall beauty. Moreover, the coating protects the underlying substrate from oxidation (including rusting, corrosion, bleaching, and fading), dry rot, water damage and even mild mechanical damage. The polymeric component of the coating compositions is chosen preferably from the class of thermoplastic polymers or copolymers generally referred to as acrylic polymers. Preferred materials include the aqueous polymer dispersions designated AC261, AC630, and HA16 and manufactured by the Rohm and Haas Company of Philadelphia, Pa. These aqueous dispersions contain approximately 50 percent polymer solids content by weight. When applying the polymer resins to a substrate in accordance with the present invention, it is usually preferred to dilute the commercially available compositions with additional solvent. The preferred solvent is water. The preferred polymer solids content in the working strength coating compositions of the present invention is in the range of 10% to 25% by weight. The films produced by these compositions are in the sub-millimeter-range thickness.
[0048] The films formed by three embodiments of this invention are colorless and transparent, thus enabling the user to enhance the visual characteristics of substrates having a variety of colors. A fourth embodiment forms a tinted and transparent film and thus allows for at least partial observation of the substrate surface textural characteristics. Typical uses of this fourth embodiment include, but are not limited to, wood items such as fences, decks, etc. A fifth embodiment forms tinted and opaque films that completely hide the substrate surface. All of these coatings also act as barriers, preventing moisture, oxygen and UV-radiation from penetrating to the substrate and causing subsequent degradation in the form of corrosion, fading, bleaching and/or moisture damage, depending on the nature of the substrate.
[0049] It has been found that these compositions can also be used as moisture barriers and gap filling sealers. When these compositions are applied to small cracks or openings, they bridge the crack or opening, thus closing it and preventing moisture or other materials from passing through. One viable use for this sealing characteristic is cracks in shingles. Other applications will be readily apparent.
SUMMARY
[0050] In accordance with the present invention, sprayable waterborne coating compositions with enhanced leveling properties comprising polymer latex resin, water, and a plurality of additives for the purpose of providing a protective, restorative, anti-mold, and anti-graffiti film barrier on a multitude of different articles and substrate types are described.
DETAILED DESCRIPTION OF THE INVENTION
[0051] The invention described in this application comprises formulas for the preparation of sprayable aqueous liquid emulsion polymer coating compositions. These compositions preferably comprise both aqueous and organic solvents. As of this filing, the organic solvents are preferably 1,2-propanediol, 2-n-butoxyethanol, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and are most preferably 1,2-propanediol, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate. All three solvents are clear, and colorless. 1,2-propanediol, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate have minimal odor and toxicity, and are not considered hazardous materials (HazMats) as defined by the Code of Federal Regulations (49 CFR). However, it is anticipated that other solvents probably including, but not limited to, those in the alcohol, glycol, glycol ether, glycol ether acetate, phthalate ester, trimellitate ester, adipate ester, and ketone groups of organic compounds should produce functionally similar compositions. 1,2-propanediol, 2-n-butoxyethanol, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate are preferably present in the final composition in the range of 0-99.9% by volume.
[0052] These compositions are waterborne emulsion polymer coatings. The organic solvents perform three possible functions: They act as coupling agents between the aqueous phase and the water-insoluble polymer molecules, promoting homogeneity between the two. As the compositions cure, they act as coalescing agents, fusing the polymer particles into a smooth, clear, continuous film that is both flexible and stretchable under ambient conditions. In the absence of a coalescing agent, the cured compositions are hard, brittle, and glass-like at normal room temperatures. And, the organic solvents serve as wetting agents because they have a lower surface tension than water.
[0053] Water serves as a diluting solvent. Water is cost-effective, non-toxic, non-hazardous, and chemically inert. However, it is anticipated that other solvents would probably produce functionally similar compositions. Water is added to lower the viscosity and increase the volume of the final compositions in order to achieve the desired consistency with respect to spreadability during application, surface coverage, and final coating thickness. Water is preferably present in the final compositions in the range of 0.1-99.9% by volume. Water is present in the preferred embodiments of this invention at an amount that also renders them amenable to application by spraying.
[0054] As of this filing, these compositions are preferably based on three commercially available aqueous liquid emulsion polymer mixes, Rhoplex HA-16, Rhoplex AC-630, and Rhoplex AC-261. These acrylic-based latex resin mixes are manufactured by the Rohm and Haas Company, Philadelphia, Pa. They are milky-white viscous liquids. These mixes comprise approximately 50% water, and 50% polymer by weight. A surfactant is present as a minor constituent. The polymer molecules are present in the form of colloidal-sized spherical particles that are coated with the surfactant. These three mixes contain most of the polymer solids that form the final surface film. Only the polymer and surfactant remain in the final cured composition. The water and organic solvents volatilize. However, trace amounts of organic solvent may remain.
[0055] The emulsion polymerization process is characterized by the formation of micelles. Micelles are colloidal-sized spheres, which are formed when a surfactant is dissolved in water above a certain critical concentration. When micelles are formed in the presence of dispersed monomer, monomer is absorbed and the micelles become swollen. When water-soluble free-radical initiators are added to the system, they are also absorbed by the micelles. Consequently, most of the polymerization process occurs inside of the micelles. The resultant colloidal spheres are referred to as polymer latex resin particles. The surfactant acts as an emulsifier, promoting miscibility between the hydrophobic polymer molecules and the aqueous phase.
[0056] Rhoplex HA-16 is preferably present in the final compositions in the range of 0.1-99.9% by volume. Rhoplex AC-630 is preferably present in the final compositions in the range of 0.1-99.9% by volume. Rhoplex AC-261 is preferably present in the final compositions in the range of 0.1-99.9% by volume.
[0057] It is anticipated that many monomers including, but probably not limited to, monomers in the acrylate/methacrylate class of monomers should produce functionally similar compositions. A presumably partial list of suitable starting monomers preferably comprises methyl acrylate, methyl methacrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, propyl methacrylate, ethoxyethyl acrylate, methoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, butyl methacrylate, isobutyl methacrylate, lauryl acrylate, stearyl acrylate, acrylic acid, methacrylic acid, butanedioc acid, ethylene acetate, propylene acetate, vinyl acetate, vinyl toluene, styrene, butadiene, isoprene, isobutylene, acrylonitrile, and methacrylonitrile.
[0058] Nine different types of additives are also present in the preferred embodiments of this invention: defoamer, pigments, pigment dispersing agent, hiding agent and/or filler, microbicide, matting agent, rheology modifiers, wetting agent, and base. The emulsifier in the polymer resin promotes foam formation during application. If the foam does not dissipate, a clear, smooth final film will not be formed. Residual foam appears as white streaks on the surface. In order to minimize foam formation during application, and enhance foam dissipation before film formation, a defoamer has been added to the system. The defoamer is preferably a silicon-based defoamer, and most preferably Dow Corning 62 Additive or Dow Corning 65 Additive.
[0059] The film formed by this invention is inherently fungi (mold, mildew, and algae) resistant because it is water-resistant, which prevents the substrate from absorbing moisture. Fungi require a moist substrate to grow. However, a more aggressive approach to mold prevention has been employed by also adding a microbicide, also known as a biologically-active compound, also known as an anti-microorganism or antifouling agent. The microbicide is preferably Rohm and Haas Rocima 20, Rocima 63, or Rocima 80, and most preferably Rohm and Haas Rocima 63. However, it is anticipated that many of the commercially available microbicide additives would be compatible with this system, and would provide broad-spectrum anti-fungal properties.
[0060] Rocima 63 has three active ingredients, 2-n octyl-4-isothiazolin-3-one, methylbenzimidazole-2-yl carbamate and N′-(3,4 dichlorophenyl)-N-N-dimethylurea, for long-lasting performance against a broad range of fungi and algae. The physical properties of Rocima 63 are such that it will not cause yellowing or chalking, and it has excellent dispersibility when added to coating compositions.
[0061] Rocima 63 has two modes of protective action: 1) It prevents the treated surface from serving as the substrate for contaminating microorganisms to grow and proliferate. 2) When the surface becomes wet through rain or condensation, the controlled diffusion of the active ingredients into the wet phase prevents the growth of micro-organisms on the surface layer.
[0062] The preferred embodiments of this invention also comprise rheology modifiers, and a surfactant. The rheology modifiers chosen comprise both a flow and leveling agent, and a thickener or thickening agent. The addition of a thickening agent makes the composition more viscous. The advantages of a more viscous product are three-fold: 1) It promotes better (more even) wetting on smooth, non-porous substrates, on which a similar, but lower viscosity, water-based composition would tend to bead, analogous to the way water beads on a recently waxed and polished automobile. 2) It minimizes sag and drip on non-horizontal substrates. 3) Also, a thicker film is easier to achieve using a more viscous composition. An appropriate application for more viscous coating compositions is on smooth metal substrates.
[0063] The addition of a flow and leveling-type rheology modifier improves the flow characteristics of the composition during application, which, in turn, enhances leveling of the uncured film, resulting in a smoother final finish. The addition of a surfactant improves wetting (minimizes beading) and also enhances leveling.
[0064] The rheology modifiers are preferably polyurethane or acrylic type rheology modifiers, and are most preferably Rohm and Haas Acrysol TT-615, and Rohm and Haas Acrysol 2020NPR. The wetting agent is preferably a silicon or fluorocarbon-based wetting agent, more preferably Zonyl FSP and Zonyl FS 610, and most preferably Zonyl FS 610.
[0065] Tints are added to the system to give the final film color. Matting agent is added to produce a satin-to-matt final, cured film. Hiding agent is added for the purpose of making the final, cured film opaque. In the absence of tints, matting agent, and hiding agent, the final film is clear, shiny, and colorless. The hiding agent in the preferred embodiments of this invention is preferably titanium dioxide, and most preferably DuPont TiPure R706. However, other commercially available hiding agents should be compatible with these compositions, and should provide the desired level of opacity. All of the commercially available tint concentrates are suitable for use in this invention. All of the commercially available matting agents should also be compatible with this invention. When titanium dioxide is added to the system, in the absence of tint and matting agent, the final, cured film is opaque, white and shiny. When titanium dioxide and matting agent are added to the system, in the absence of tint, the final, cured film is opaque, white and satin-to-matt finish. As of this filing, the tints used in this invention are preferably the ‘Series 2000 Dispersions’ manufactured by Eagle Sales Company, St. Louis, Mo. As of this filing, the matting agent is preferably ‘EZ Flat’, also manufactured by Eagle Sales Company.
[0066] A tint dispersing agent has also been added to the preferred embodiments of this invention. The tint dispersing agent has been added for the purpose of ensuring that both the tint and the hiding agent disperse evenly in the composition so that an even and consistent amount of color and opacity is observed throughout the final film. The tint dispersing agent in the preferred embodiments of this invention is preferably an acrylic-type dispersing agent, is more preferably Rohm and Haas Tamol 731A and Tamol 165A, and is most preferably Rohm and Haas Tamol 731A. However, it is anticipated that many of the commercially available tint dispersing agents would be compatible with this invention, and would provide a level of dispersion consistent with an aesthetically pleasing final cured film.
[0067] The defoamer, pigment, pigment dispersing agent, hiding agent, microbicide, matting agent, rheology modifiers, and surfactant are preferably present in the final compositions in the range of 0-99.9% by volume. A base may be required, at an amount sufficient to raise the pH of the system to between 7 and 12 pH units for the purpose of stabilizing the system. At lower pH, one or more of the solids constituents may precipitate. The base is preferably a strong inorganic base, and is most preferably ammonium hydroxide.
[0068] All of the uncured compositions, when tint concentrate is excluded, look very similar to 2% milk with respect to color, and opacity. The two best mode embodiments (uncured) that do not comprise rheology modifiers are very similar to 2% milk with respect to viscosity also. The other three best mode embodiments (uncured) are significantly more viscous.
[0069] One best mode embodiment forms a final cured coating that is opaque and tinted. A second, best mode embodiment forms a final, cured film that is clear and tinted. The three remaining best mode embodiments form final cured films that are clear and colorless on the recommended substrates. The final films are either shiny, satin, or matt, depending on the amount of matting agent added to the system, the nature of the substrate, and the number of coats applied. All of these compositions produce final cured coatings that are resilient, durable, monolithic, and are not oily or slippery. All of these compositions, with the exception of the best mode embodiment for use as an automotive anti-graffiti coating, are anti-mold. All of these compositions, with the exception of the best mode embodiment comprising hiding agent and/or filler, are anti-chalk, and anti-fade. When two coatings of the lower viscosity, best mode embodiments are applied at a thickness that achieves complete coverage, but without running or dripping, they cure to a micrometer-range final thickness. The higher viscosity, best mode embodiments produce thicker final films than the lower viscosity, best mode embodiments.
[0070] If a matt final finish is preferred instead of the satin/shiny finish that is inherent of all five best mode embodiments described below, a matting agent may be added. The matting agent is preferably a wax or silica-based matting agent, and more preferably a silica-type matting agent, and most preferably EZ Flat. The matting agent is preferably present in the final composition in the range of 0-99.9% by volume, and more preferably present at 0% to 6% total solids content. When a matting agent is used, the water content in the composition is reduced by the volume-equivalent of matting agent concentrate added.
[0071] All of these compositions cure to a durable, flexible, stretchable, air tight, and waterproof plastic-like final coating. The cured compositions are non-toxic. The cured compositions protect the substrate from the surface-degradation effects of moisture, ozone, ultraviolet rays (UV), and oxidation. The cured compositions inhibit mold, mildew, algae, and moss growth. The cured compositions inhibit dry rot and water damage. Due to their malleable nature, the cured compositions will not blister, crack, chip, or peel, unlike most lacquers, varnishes, shellacs, and conventional latex paints. When applied to substrates on which surface-wear is anticipated, these compositions will wear instead of the substrate, thus extending the life of the substrate.
[0072] There are a number of highly suitable articles on which the coating compositions of the present invention are particularly attractive. These compositions are recommended for use on a variety of substrates and objects including, but not limited to, vinyl, leather, latex and oil-based paints, metal, bare wood, stained or painted wood, lacquered or varnished wood, veneer, plastic, rubber, grout, caulking, concrete, brick, stone, stucco, fiberglass, ceramic tile, etc. The compositions that comprise rheology modifiers are the better choice on smooth metal surfaces, and some types of new-looking, smooth-textured plastics, linoleum, and on freshly coated lacquered and varnished surfaces. On these types of substrates the compositions that do not comprise rheology modifiers tend to bead, and so do not always form a smooth, continuous film. However, these lower viscosity compositions may be used on these types of substrates when the item is older, and the surface has become weathered. On such surfaces, all of the best mode embodiments that cure to a clear and colorless final film will partially-to-fully rejuvenate both the color and the luster. The extent to which the color and luster will be rejuvenated will depend on the condition of the substrate at the time it is treated.
[0073] These compositions also will not yellow with age. These compositions will maintain their integrity on the recommended substrates at all temperatures ranging from zero to three hundred degrees Fahrenheit. It is anticipated that these compositions may maintain their integrity at even lower and higher temperatures than the range cited. However, this parameter has not been fully investigated.
[0074] These compositions should not be applied in direct sunlight during the heat of the day, or on surfaces that are hot or uncomfortably warm to the touch. Under these conditions, these compositions may dry too quickly, which may in turn compromise the appearance and/or structural integrity of the final cured composition. Also, do not apply the best mode embodiments that form clear and colorless final films when the temperature is below 40 degrees Fahrenheit, the best mode embodiment that forms an opaque and tinted final film when the temperature is below 50 degrees Fahrenheit, and the best mode embodiment used as an automotive anti-graffiti coating when the temperature is below 60 degrees Fahrenheit, or a proper film may not form and the finish may be hazy. When the air and/or substrate temperature is at or near the minimum recommended application temperatures, it is advisable to prepare a small test site first on the surface to be coated, to ensure that the desired finish will be attained.
[0075] To ensure proper adhesion and a smooth finish, the substrate should be clean, dry, and free of oils, wax or silicone-based finishes such as Pledge or Armor All, grease, soap film, dust, and dirt before applying. Appropriate cleaning solvents include, but are not limited to, soap and water, alcohol, ammonia-based window cleaners, etc. Any residue left by the cleaning solvent itself (for example, soap film) should also be removed. A high-pressure hose or pressure washer is recommended for cleaning large exterior surfaces. On coarse-textured horizontal surfaces such as concrete, the surface may still be damp when these compositions are applied. However, these compositions should not be applied on such surfaces when standing water is present.
[0076] Other embodiments of this invention preferably comprise other additives such as pigments (tints), hiding agents, dispersants, anti-blocking agents, fillers, adhesion promoters, accelerators, matting agents, surfactants, solvents, defoamers, rheology modifiers, preservatives, humectants, pH controllers, anti-freezes, coalescents, plasticizers, wetting agents, coupling agents, and microbicides.
General Specification
[0077] Now the subject of this patent application may be more generally described as follows: The liquid emulsion polymer coating compositions are comprised of twelve types of components, namely, polymer, a means of diluting the polymer, a means of making the final cured polymer coating more flexible and stretchable, a means of homogenizing all of the components in solution, a means of modifying the rheology of the uncured compositions, a means of minimizing foam formation and promoting foam dissipation during application, a means of wetting and leveling as the compositions cure, a means of adjusting the pH of the system, a means of adding color (tint) to the final, cured film, a means of effectively dispersing the tint(s) (pigment(s)) homogenously throughout the final, cured films, a means of making the final films opaque, thereby effectively hiding the substrate, a means of producing a satin or matt finish on the final, cured films, and a means of inhibiting fungal growth on the cured coatings and substrate.
[0078] The means of making the final coatings more flexible and stretchable is preferably a coalescing agent, and is more preferably an organic solvent. The means of diluting the polymer is preferably a liquid solvent and is most preferably water. The means of homogenizing these types of components in solution is preferably a surfactant, also known as an emulsifier. The means of inhibiting foam formation and dissipating foam formed during application is preferably a defoamer. The means of inhibiting fungal growth is preferably a microbicide. The means of modifying the rheology of the uncured compositions is preferably a rheology modifier. The means of causing the compositions to wet and level better during the curing process is preferably a surfactant. The means of altering the pH is preferably an acid or a base. The means of producing a matt final finish is preferably a matting agent. The means of making the final films opaque is preferably a hiding agent or filler. The means of adding color to the final, cured films is preferably a tint (pigment). The means of effectively dispersing the tint(s) (pigment(s)) homogenously throughout the final, cured films is preferably a dispersing agent.
[0079] The means of diluting preferably lowers the viscosity of the mixture and increases the volume of the final compositions. Lowering the viscosity is a means of making the final compositions easier to spread, and renders them amenable to various modes of application, including spraying. Increasing the volume is also a means of increasing the surface coverage, and achieving a more desirable thinner final coating. These compositions may also include a means of removing stains from the substrate surface. The means of stain removal is preferably a low boiling point organic solvent.
[0080] Other embodiments of these inventions preferably comprise a means of increasing the shelf life of the uncured compositions, a means of making the final film less tacky, a means of making both uncured and cured compositions more bulky, and a means of preventing the uncured compositions from denaturing if they freeze. The means of extending the shelf life of the uncured compositions is preferably a preservative. The means of preventing the uncured compositions from denaturing if they freeze is preferably an anti-freeze. The means of making the final films less tacky is preferable an anti-tack or an anti-blocking agent. The means of making the compositions more bulky is preferably a filler or an extender pigment.
Operation
[0081] These compositions are amenable to various modes of application, including, but not limited to, spraying, brushing, rolling, and wiping. Suitable spray applicators include plastic plant misters for small projects, and the larger pump-style compressed air or airless sprayers for broader surface area coverage. The residual droplet that often cures in the spray tip may be easily removed with a pin or other suitable implement. Various types of absorbent paper and cloth products may be used as wipe applicators. White cloth applicators are recommended because the dyes in colored materials may bleed and discolor the finish. Sponges may also be used. Wiping is only recommended on surfaces that are not abrasive enough to compromise the structural integrity of the applicator. Otherwise, small particles of the applicator material may end up stuck to the surface. Conventional paintbrushes and paint rollers are recommended for brushing and rolling, respectively. A clean broom is a suitable tool for spreading these compositions on rough horizontal surfaces such as asphalt and concrete.
[0082] When wiping or rolling these compositions, avoid employing a brisk scrubbing or buffing action, especially on smooth nonporous substrates such as painted garage doors, otherwise excessive foaming may occur which may not completely dissipate before curing. If the substrate is cool to the touch during application, any foam that forms should effectively dissipate. However, as recommended previously, avoid applying this composition in direct sunlight during the heat of the day. Smoother strokes with a thoroughly wetted applicator are recommended. If some white streaks persist after curing due to foaming, application of an additional coating using a thoroughly wetted applicator and a smoother applicating motion should resolve the problem. For this same reason, cloth and absorbent paper applicators may perform better than sponges, which also tend to promote foaming. Any residual foam ‘blemishes’ should partially-to-fully dissipate by weathering over time.
[0083] A very desirable attribute of these compositions is their relatively short curing time. Depending on the type, texture, and porosity of the substrate, and typical curing time variables including temperature, humidity, air flow over the surface, and the amount of headspace available for effective dissipation of solvent vapors, curing times of between ten and twenty minutes for the lower viscosity compositions, and between twenty and thirty minutes for the more viscous preferred embodiments not comprising hiding agent are typical for relatively smooth surfaces. On rougher horizontal surfaces such as asphalt, where some pooling is expected, longer curing times are anticipated. The preferred embodiment comprising hiding agent typically requires a few hours to properly set up and form a ‘surface skin’ that is dry to the touch. Unless otherwise stated, at least two coats are recommended for most uses of all of the best mode embodiments. The best mode embodiment designed for use as an automotive anti-graffiti coating has been formulated to be a one coat system when used for this application.
[0084] All of the best mode embodiments, with the exception of the one designed for use as an automotive anti-graffiti coating, are mold and mildew inhibitors. These compositions are not designed to eliminate existing mold and mildew problems. A separate treatment process must be performed first. When applied to a clean surface, these compositions have proven extremely effective at preventing mold and mildew growth. When applied to a surface with an existing problem, they will inhibit additional mold and mildew growth. Suitable applications include, but are not limited to, shower curtains, shower stalls, various other bathroom surfaces, most hard and soft wood substrates such as decks, fences, arbors, wood siding, and cabinets, painted surfaces, drywall, wooden structural members, basements, concrete, brick, rock, stucco, wood/vinyl sided building exteriors, shingles etc. These compositions will also inhibit water damage on wood substrates. These compositions will also inhibit moss growth, which usually occurs on outdoor surfaces, including but not limited to, concrete and brick, sidewalks, driveways, various types of roofing and siding materials, etc.
[0085] The best mode embodiment comprising tints, filler and/or hiding agent is suitable for use on all articles and substrate types on which most conventional latex paint products are applicable.
[0086] The best mode embodiment designed for use as an automotive anti-graffiti coating has been specifically formulated for use on high luster painted metal substrates, including but not limited to, automobile, truck, and railroad car exteriors, etc. On such surfaces, it will also restore both the color and luster on faded and worn substrates. The extent of rejuvenation will depend on the condition of the substrate at the time it is treated. In addition, paint, ink, marker, stain, food stains, dirt, etc. that are intentionally or unintentionally applied to a substrate coated with this composition will not migrate through the coating; they will remain on the surface of the film. To remove the unwanted discoloration, simply wipe the surface with a mild detergent and water solution. If this does not remove the discoloration, the film itself may be removed with a mild organic solvent such as ethanol, denatured alcohol or isopropanol, thus effectively removing the unwanted discoloration. Once sufficiently clean and dry, the surface can then be recoated with this best mode embodiment to again restore the color and luster, and to re-establish the anti-graffiti protection. Other substrates that this best mode embodiment may be used on include, but are not limited to, bare metal, oil and latex-painted substrates, wood, plastic, vinyl, stucco, concrete, brick, rubber, etc.
[0087] The preferred embodiments that form clear and colorless films restore the color, enhance the luster, and waterproof soft leather, and many hard leather items. Recommended uses include, but are not limited to, shoes and boots, belts, clothing items, purses, wallets, briefcases, luggage, saddles, car interiors, etc. However, because of the waterproofing property of these compositions, their application on leather surfaces will inhibit the leather's ability to ‘breathe’. Consequently, discretion should be exercised when applying to clothing items such as shoes, boots, leather pants, leather skirts, and leather coats. As a recommendation, when applying to shoes and boots, treat only the heal and toe areas, and possibly the seams around the bottom of the shoes or boots, to about a half an inch up from the soles, in order to waterproof and prevent the threads from rotting. These compositions also seal in the leather's natural oils, which helps prevent the leather from drying out and cracking. Analogous to the exterior paint application cited above, these compositions have proven capable of partially-to-fully restoring faded color coatings applied to leather. Consequently, these compositions may be used in place of shoe polish, provided there is still a reasonable amount of substance to the color coating remaining on the substrate. The extent to which a surface is restored will depend on its condition at the time it is treated.
[0088] The best mode embodiment comprising tint is suitable for use on any porous, and many non-porous substrates where, in addition to the sealing, waterproofing and anti-mold properties, color is also desirable. A partial list of such substrates includes, but is not limited to, wood, rubber, plastic, vinyl, oil and latex-painted substrates, concrete, brick, stone, stucco, etc.
[0089] Analogous to the paint and leather uses previously cited, the compositions that form clear and colorless final films also minimize color fading on vinyl and plastic substrates, and are effective at partially-to-fully restoring weathered and bleached vinyl, linoleum, and plastic substrates to their original color and luster. The extent to which a surface is restored will depend on its condition at the time it is treated. Also, these compositions effectively seal in the plasticizers in these materials, which might otherwise migrate to the surface and either evaporate or wear off, leaving the substrate more susceptible to drying out and cracking. These compositions are recommended for use on both newer and older items, including but not limited to, car and boat interiors, motor cycle seats, indoor and outdoor furniture, awnings, Venetian blinds, vinyl siding, chairs, etc. These compositions will not blister, crack, chip, peel, or yellow, and will protect the surface to which they are applied from cracking as well. Consequently, as the coating itself weathers, as evidenced by a loss of luster and/or renewed color fading, a fresh coat may be applied to the cleaned surface with no additional surface preparation.
[0090] An applicable substrate that is susceptible to cracking is car dashboards. However, discretion is advised when considering this application because compositions that do not comprise matting agent will make the surface shinier, which in turn will increase surface-glare from the sun. Applying one coat instead of two may produce a more desirable result. Alternatively, a matting agent may be added, as described previously, in order to produce a lower-glare final finish. On items in which surface-wear is expected, such as car or motorcycle seats, these compositions will wear instead of the surface to which they are applied, thus extending the life of that surface.
[0091] The compositions that form clear, colorless final films rejuvenate and protect weathered interior and exterior painted surfaces, and protect freshly coated interior and exterior painted surfaces from weathering. Specifically, when applied to a painted surface that has become bleached and ‘chalky’ due to UV-induced oxidation, if there is still a reasonable amount of paint substance remaining, these compositions are capable of partially-to-fully restoring the surface to its original color and luster. The extent to which a surface is restored will depend on its condition at the time it is treated. When applied to either a recently painted or somewhat weathered surface, these compositions will extend the life of the paint. These compositions will not blister, crack, chip, peel or yellow, and will prevent the paint from cracking, chipping or peeling. Consequently, as the coating itself weathers, as evidenced by a loss of luster and/or renewed color fading, a fresh coat may be applied to the cleaned surface with no additional surface preparation. Also, a fresh coat of paint may be applied directly over these compositions without any surface preparation except cleaning, as necessary.
[0092] These inventions also inhibit the drying out, hardening, and cracking of rubber substrates. These degrading processes are caused by a UV-induced reaction between rubber and ozone. Such damaged rubber, in turn, is more susceptible to dry rot. Dry rot is a decay process caused by various types of fungi. Outdoor items that are exposed to direct sunlight are more susceptible to hardening and cracking. Items that are also exposed to moisture, including high humidity, are also more likely to develop dry rot. When applied to a substrate that has an existing dry rot problem, these compositions will prevent further damage. Suggested applications include, but are not limited to, tires and various other rubber items on automobiles, motor cycles, and bicycles, including wind shield wipers, gaskets, and seals, hoses, trailer and farm equipment parts, etc. Analogous to the vinyl and plastic applications, the embodiments that form clear, colorless final films also enhance the color and luster on new rubber surfaces, and are capable of partially-to-fully restoring the color and luster on older, weathered surfaces. The extent to which a surface is restored will depend on its condition at the time it is treated.
[0093] These compositions also inhibit corrosion and pitting on metal substrates. Corrosion or oxidation on metal surfaces is caused by a reaction between the metal surface, water, and oxygen. When using the best mode embodiments that form clear, colorless final films on tarnished surfaces, use an appropriate metal cleaner first, and then remove any remaining residue with alcohol, before applying these compositions. The higher viscosity, best mode embodiments are very effective on both smooth and brushed metal surfaces. The lower viscosity, best mode embodiments may not wet evenly on smooth metal substrates. When applied to surfaces that are already corroded, these compositions will effectively seal the substrate, thus preventing additional oxidation. When the compositions that form clear, colorless films are applied to rusty surfaces, the appearance of the coated substrate is often more aesthetically appealing than the original untreated and oxidized surface. Due to the malleable nature of these compositions, they will not blister, crack, chip, or peel in response to constant, temperature-induced expansion and contraction that is inherent of metal surfaces.
[0094] The lower viscosity, best mode embodiments, with and without tint, are effective deck sealants because they inhibit water damage, including mold, mildew, and dry rot, stains, and UV-induced bleaching on wood substrates. They also seal in the wood's natural oils, which helps prevent the wood from drying out and becoming brittle and splitting. The best mode embodiment that comprises tint also adds color to the final, cured film. Other suitable applications for these compositions include wooden fences, gazebos, arbors, natural wood siding, cedar shake shingles, etc. These compositions are suitable for application on all types of hard and soft wood, including teak and pressure-treated wood.
[0095] These sealing compositions minimize stain formation due to engine oils and various other automotive and machine lubricants on concrete and asphalt substrates. Three coats are recommended for this use. Allow preferably at least a one hour curing time between coats. The preferred embodiment comprising hiding agent should be allowed to cure for at least four hours between coats. Also, the final coat should be allowed to cure preferably over night before parking an automobile on the surface. Otherwise, the coating may end up stuck to the tires instead of the substrate. Note: Some automotive products, including certain brands of power steering pump fluid and brake fluid, contain organic solvents that will migrate through the coating. Consequently, spills and drips from these products should be wiped up quickly with a dry cloth or paper towel. Otherwise, a permanent stain may result.
[0096] The sealing, waterproofing, and anti-mold properties of the best mode embodiments comprising microbicide make them suitable coatings for basements. They will seal the pores and hairline cracks on concrete, cinder block, and mortar, thus preventing moisture from penetrating through basement walls and floors that are in good repair. Consequently, mold and mildew problems are minimized. The best mode embodiment designed for use as an automotive anti-graffiti coating may also be used to coat basements, but does not offer the anti-mold property. These compositions are not designed to repair separated, cracked, or chipped basement surfaces.
[0097] All best mode embodiments that do not comprise hiding agent are anti-chalk and anti-fade. The best mode embodiments that form clear, colorless final films restore the color and luster on worn and faded painted substrates, and protect new painted substrates from fading and becoming chalky. Consequently, these embodiments are useful for restoring and protecting metal roofs. Analogous to rubber, asphalt shingles, tarpaper, and various other roofing materials become brittle and crack with age. These compositions inhibit these UV-oxygen-induced weathering effects. Also, these compositions seal roof leaks. Recommended applications include, but are not limited to, asphalt, cedar shake, and metal roofs. Also, often pinhole-sized perforations form in metal roofs, possibly due to oxidation of the tiny metal impurities (i.e. other types of metals) within the surface. These compositions are effective at sealing holes that are less than approximately 1 mm in diameter. When a more liberal amount of the lower viscosity preferred embodiment compositions are applied in order to promote running, the fluid nature of these compositions allow them to ‘find’ and seal cracks that are less than approximately 1 mm wide, and holes that are less than approximately 1 mm in diameter. The preferred embodiments comprising rheology modifiers would be the more suitable compositions for sealing larger holes and seams. These compositions may also be applied to newer metal roofs to prevent perforations from forming.
[0098] These compositions protect surfaces from cosmetic damage caused by accidental spills or marks, and graffiti. These compositions resists penetration from common types of dirt, paint, felt marker, ball point pen, dyes, grease, oil, food stains, body oils, and even some acids, making cleanup much easier. However, some felt markers contain MEK, which is a strong solvent capable of etching the surface of the coating. Etching makes cleanup more difficult, and sometimes not possible. In such cases, the graffiti and the coating itself can be effectively removed from the substrate using a mild organic solvent such as ethanol, denatured alcohol or isopropanol. Stronger solvents like methyl ethyl ketone or acetone may also be employed. Once the graffiti and coating have been effectively removed, a fresh coating of this composition may be applied, as necessary.
[0099] These compositions protect surfaces from the damaging effects of freeze-thaw. Freeze-thaw occurs when water freezes in hairline cracks. When water turns to ice it expands, exerting pressure on the walls of the crack. This pressure, in turn, causes the crack to grow. As the cycle of freezing and thawing continues, the cracks will continue to grow. Coating the substrate while the cracks are still hairline-thickness prevents moisture from entering the cracks and initiating the freeze-thaw cycle. Applicable substrates include, but are not limited to, concrete, asphalt, and various types of shingles. These compositions are also effective at inhibiting the pitting effect that occurs when concrete driveways and walkways are salted in the wintertime. Salt pitting is also a freeze-thaw phenomenon.
[0100] The embodiments that form clear, colorless final films repair minor blemishes on wood furniture due to scratches or scuffs. Also, these compositions may be used to seal bare, stained, lacquered and/or varnished, and painted wood surfaces in order to prevent watermarks caused by moist flowerpots or condensation on cold drinking glasses, etc. As mentioned previously, if the lacquered or varnished surfaces are relatively new and very smooth, the preferred embodiments comprising rheology modifiers would probably perform better than the lower viscosity preferred embodiments, which would be less likely to wet evenly. Applications comprise both finished and unfinished items including, but not limited to, cabinetry, furniture, chairs, picture frames, shelving, etc. The compositions that form clear, colorless final films often enhance the color and luster of both treated and untreated wood surfaces. Unlike most furniture polishes, smudges and fingerprints will not form on the films formed by these compositions, even when applied to furniture. Also, they have ‘anti-static’ properties, and as a result, do not promote dust accumulation. These compositions will inhibit stain formation on unfinished wood surfaces.
[0101] The compositions that form clear, colorless final films protect and produce a nice finish on various types of sporting equipment including, but not limited to, golf clubs, wood, metal, fiberglass, and graphite composite surfaces on tennis racquets, firearms and bows, etc. Because these compositions are not oily and are relatively non-slippery, their application on these types of sporting goods will not compromise their performance. However, it is a matter of personal preference whether or not to apply these compositions on golf club and tennis racquet grips since they may alter the ‘feel’ of these surfaces. Similarly, discretion is advised with respect to applying to golf club faces.
[0102] The best mode embodiments that form clear, colorless final films protect, enhance the colors, and provide an aesthetically pleasing luster on newer or older picture frames, latex and oil-based paintings, and painted, lacquered, or bare, wooden and ceramic handcrafted items.
[0103] The best mode embodiments that form clear, colorless films also enhance the color and luster, protect, and waterproof hardbound book covers. Recommended applications include, but are not limited to, new or used high school and university text books, encyclopedia sets, dictionaries, etc. The extent to which a surface is restored will depend on its condition at the time it is treated.
[0104] These compositions are effective sealants for electrical components, circuit boards, wiring, automobile battery terminals, etc., that may be exposed to moisture and/or chemically corrosive environments. Once the solvents have evaporated and these compositions have cured, they are nonconductive.
[0105] The compositions that do not comprise hiding agent may also be used as waterproofing sealants for canvas and nylon fabrics because they are very flexible and will not crack, chip or peel. Applications include, but are not limited to, tents, pop-up camper canopies, awnings, automobile convertible tops, storage covers, etc. In addition, when such items or rolled up and/or placed in storage, the best mode embodiments that comprise anti-microorganism agent will inhibit mold and mildew growth.
[0106] These compositions are not recommended for use on moving mechanical parts. Do not apply over oil-based coatings that are not completely cured because any residual oil may otherwise compromise the appearance and/or structural integrity of the final cured coating.
[0107] These compositions are all water soluble until cured, which facilitates relatively quick and easy cleanup of spills, and all of the various types of applicators and receptacles that might be employed. These compositions are relatively safe and easy to use, and when cured, are all non-flammable, non-combustible, and non-toxic. These compositions are also never oily and are relatively non-slippery.
[0108] These compositions should be applied full strength; do not dilute. Surfaces that have been protected with these compositions should be cleaned with a damp cloth. If the surface has become stained, wipe with a mild detergent and water solution, rinse with water, and wipe dry. Avoid the use of abrasive cleaning products, mineral spirits, and organic solvents. Rubbing alcohol and denatured alcohol are the preferred solvents for the purpose of intentionally removing these compositions from a surface after they have cured.
[0109] Residual concrete that has partially-to-fully set on tools, receptacles, and vehicles is more easily cleaned off when the affected surface has first been treated with these compositions. Instead of having to use a mild muriatic acid solution to chemically treat the concrete stains, usually all that is required is spraying with a hose or a pressure washer.
[0110] Soap scum and water hardness spots don't form as easily on, and are more easily removed from, surfaces that are coated with these compositions.
[0111] The present invention will be explained in further detail by reference to a description of the preferred embodiments. The following examples illustrate but do not limit the invention. All proportions are expressed as percentages by volume.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Example 1
[0112] In a suitably sized, chemically inert receptacle, mix 47.7% Rhoplex AC-261, 39.4% water, 0.95% Tamol 731A, 0.03% Zonyl FS-610, 0.20% DuPont #65 Additive, 1.2% Rocima 63, 0.24% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 9.6% Acrysol RM 2020NPR, and 0.72% Acrysol RM TT615, until completely homogenous. Add between 0 and 180 ml of DuPont TiPure R706 titanium dioxide per gallon (added as a dry powder−tamped dry density=1.0 grams/milliliter). The actual amount added is dependant on the tint concentrate color that will be used.
[0113] Tint concentrate is added at the end, and is preferably added at an amount of between 0% and 10% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706, and is more preferably added at an amount of between 0% and 2.0% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706. EZ Flat matting agent is also added at the end, after the tint concentrate, at an amount preferably between 0% and 10% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706 and the tint concentrate, and is more preferably added at an amount of between 0% and 5.0% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706 and the tint concentrate. The amount of EZ Flat added is dependant on the amount of satin-to-matt finish desired in the final film.
[0114] Another preferred alternative mixing scheme for the EXAMPLE 1, best mode embodiment is as follows: In a suitably sized, chemically inert receptacle, mix 47.7% Rhoplex AC-261, 0.96% Tamol 731A, 0.03% Zonyl FS-610, 0.20% DuPont #65 Additive, 1.2% Rocima 63, 0.24% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 9.6% Acrysol RM 2020NPR, and 0.72% Acrysol RM TT615, until completely homogenous. Add between 0 and 300 ml of DuPont TiPure R706 titanium dioxide per gallon (added as a dry powder−tamped dry density=1.0 grams/milliliter) of concentrate. The actual amount added is dependant on the tint concentrate color that will be used.
[0115] Tint concentrate is added at the end, and is preferably added at an amount of between 0% and 16.5% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706, and is more preferably added at an amount of between 0% and 3.3% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706. EZ Flat matting agent is also added at the end, after the tint concentrate, at an amount preferably between 0% and 16.5% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706 and tint concentrate, and is more preferably added at an amount of between 0% and 8.3% of the sum total volume of all of the above-mentioned components, excluding DuPont TiPure R706 and tint concentrate. The amount of EZ Flat added is dependant on the amount of satin-to-matt finish desired in the final film. This concentrated mix can then be shipped at a reduced cost. The recipient then adds 39.4% water (percentage is based on the sum total of all percentages of constituents used to mix the concentrate composition, excluding the tint, TiPure R706, and EZ Flat), with stirring, until completely homogenous.
Example 2
[0116] In a suitably sized, chemically inert receptacle, mix 24.3% Rhoplex AC-261, 74.1% water, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% #65 Additive, until completely homogenous. Tint concentrate is added at the end, and is added at an amount preferably between 0% and 10% of the sum total volume of all of the above-mentioned components, and more preferably between 0% and 2.0% of the sum total volume of all of the above-mentioned components.
[0117] A preferred alternative mixing scheme for the EXAMPLE 2, best mode embodiment is as follows: In a suitably sized, chemically inert receptacle, mix 24.3% Rhoplex AC-261, 24.5% water, and 1.2% Rocima 63, until completely homogenous. In a separate suitable receptacle, mix 49.6% water, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% #65 Additive, until completely homogenous. Both of these intermediate compositions are indefinitely stable. In a separate suitable receptacle large enough to accommodate the total volume, combine the total contents of both intermediate mixtures, with stirring, until completely homogenous. The two intermediate mixtures may be decanted into the larger receptacle at the same time, or one at a time in either order, to prepare the final composition. Tint concentrate is added at the end, and is added at an amount preferably between 0% and 10% of the sum total volume of all of the above-mentioned components, and more preferably between 0% and 2.0% of the sum total volume of all of the above-mentioned components.
[0118] Another preferred alternative mixing scheme for the EXAMPLE 2, best mode embodiment is as follows: In a suitable receptacle, mix 24.3% Rhoplex AC-2612, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% #65 Additive, until completely homogenous. Tint concentrate is added at the end, and is added at an amount preferably between 0% and 40% of the sum total volume of all of the above-mentioned components, and more preferably between 0% and 8.0% of the sum total volume of all of the above-mentioned components. This concentrated mix can then be shipped at a reduced cost. The recipient then adds 74.1 % water (percentage is based on the sum total of all percentages of constituents used to mix the concentrate composition, excluding the tint), with stirring, until completely homogenous.
Example 3
[0119] In a suitably sized, chemically inert receptacle, mix 49.8% Rhoplex AC-261, 44.8 % water, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 5.0% Acrysol RM 2020NPR, 0.10% #65 Additive, and 0.13% Acrysol RM-TT615, until completely homogenous.
[0120] Another preferred alternative mixing scheme for the EXAMPLE 3, best mode embodiment is as follows: In a suitably sized, chemically inert receptacle, mix 49.8% Rhoplex AC-261, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 5.0% Acrysol RM 2020NPR, 0.10% #65 Additive, and 0.13% Acrysol RM-TT615, until completely homogenous. This concentrated mix can then be shipped at a reduced cost. The recipient then adds 44.8% water with stirring, until completely homogenous.
Example 4
[0121] In a suitably sized, chemically inert receptacle, mix 24.5% Rhoplex AC-261, 73.9% water, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% 65 Additive, until completely homogenous.
[0122] A preferred alternative mixing scheme for the EXAMPLE 4, best mode embodiment is as follows: In a suitably sized, chemically inert receptacle, mix 24.5% Rhoplex AC-261, 24.3% water, and 1.2% Rocima 63, until completely homogenous. In a separate suitable receptacle, mix 49.6% water, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% 65 Additive, until completely homogenous. Both of these intermediate compositions are indefinitely stable. In a separate suitable receptacle large enough to accommodate the total volume, combine the total contents of both intermediate mixtures, with stirring, until completely homogenous. The two intermediate mixtures may be decanted into the larger receptacle at the same time, or one at a time in either order, to prepare the final composition.
[0123] Another preferred alternative mixing scheme for the EXAMPLE 4, best mode embodiment is as follows: In a suitable receptacle, mix 24.5% Rhoplex AC-261, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and 0.20% 65 Additive, until completely homogenous. This concentrated mix can then be shipped at a reduced cost. The recipient then adds 73.9% water, with stirring, until completely homogenous.
Example 5
[0124] In a suitably sized, chemically inert receptacle, mix 24.6% Rhoplex AC-261, 72.8% water, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 0.01% Zonyl FSP, and 1.1% RM-TT615, until completely homogenous.
[0125] A preferred alternative mixing scheme for the EXAMPLE 5 best mode embodiment is as follows: In a suitably sized, chemically inert receptacle, mix 24.6% Rhoplex AC-261, 1.2% Rocima 63, and 24.2% water, until completely homogenous. In a separate suitable receptacle, mix 48.6% water, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 0.01% Zonyl FSP, and 1.1% RM-TT615, until completely homogenous. Both of these intermediate compositions are indefinitely stable. In a separate suitable receptacle large enough to accommodate the total volume, combine the total contents of both intermediate mixtures, with stirring, until homogenous. The two intermediate mixtures may be decanted into the larger receptacle at the same time, or one at a time in either order, to prepare the final composition.
[0126] Another preferred alternative mixing scheme for the EXAMPLE 5, best mode embodiment is as follows: In a suitable receptacle, mix 24.6% Rhoplex AC-261, 1.2% Rocima 63, 0.25% 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 0.01% Zonyl FSP, and 1.1% RM-TT615 until completely homogenous. This concentrated mix can then be shipped at a reduced cost. The recipient then adds 72.8% water, with stirring, until completely homogenous.
Anti-Mold Testing Example
[0127] In order to evaluate the efficacy of the anti-mold feature of the present invention under extreme conditions, one of the preferred embodiments that does not comprise tints, matting agent, filler and/or hiding agent was subjected to ASTM Method D4445-03, ‘Standard Test Method for Fungicides for Controlling Sapstain and Mold on Unseasoned Lumber’.
[0128] In accordance with this method, two coats of the test composition were applied to pieces of unseasoned sapwood. As controls, test samples were also prepared with a similar test composition that did not comprise anti-microbial agent. Untreated pieces of unseasoned sapwood were also prepared. All of these test samples were then inoculated with spores from several types of fungi, and placed in a high humidity chamber maintained at 25° C. (77° F.) for eight weeks.
[0129] The testing was performed by Dr. David Westenberg, who is an Associate Professor of Biological Sciences at the Missouri University of Science and Technology (formerly known as the University of Missouri-Rolla). Dr. Westenberg described the test results this way: “When applied as directed (two coats) the test composition (with microbicide) treated wood shows no fungal growth after continuous exposure for a period of 8 weeks whereas untreated and non-microbicide (the test composition without microbicide) treated samples showed fungal growth after less than 2 weeks of exposure.”
[0130] The preferred embodiment comprising titanium dioxide should inherently provide enhanced anti-microbial properties because titanium dioxide is also an anti-microbial agent.
CONCLUSION
[0131] While the present invention has been described in terms of a series of preferred embodiments thereof, it is to be appreciated and anticipated that those skilled in the art may readily apply these teachings to other possible variations of the invention. Various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best modes contemplated for carrying out the process of the invention but that the invention will include all embodiments falling within the scope of the appended claims and legal equivalents. | Sprayable liquid emulsion polymer coating compositions comprised of polymer resin and a plurality of additives for the purpose of protecting, restoring, reconditioning, rejuvenating, and enhancing the color, luster and durability of a multitude of different newer and older substrate types. These coating and sealing compositions are anti-mold, anti-graffiti, they withstand temperatures up to, and most likely in excess of, 300 degrees Fahrenheit without compromising their structural integrity, and they protect against the substrate-degrading effects of oxygen, ozone, UV-radiation, moisture and dry rot. They are also environmentally and user-friendly because they comprise minimal amounts of hazardous constituents. | 2 |
[0001] This application claims the benefit of U.S. Patent Application Serial No. 60/345,758, filed on Dec. 31, 2001
BACKGROUND OF THE INVENTION
[0002] In the copolymerization of 1,3-butadiene and isoprene with unmodified neodymium catalysts, the 1,3-butadiene polymerizes about 19 times faster than the isoprene. For this reason, such copolymers do not have a random distribution of monomers. One end of the polymer chains contain mostly repeat units which are derived from butadiene (which polymerized faster) and the other end of the polymer chains contain mostly repeat units which are derived from isoprene (which polymerized slower). As the polymerization proceeds, the availability of butadiene monomer for polymerization diminishes leaving more and more isoprene to polymerize subsequently. This causes such isoprene-butadiene rubbers to be tapered.
[0003] U.S. Pat. No. 4,663,405 discloses that conjugated diolefin monomers can be polymerized with a catalyst system which is comprised of (1) an organoaluminum compound, (2) an organometallic compound which contains a metal from Group III-B of the Periodic System, such as lanthanides and actinides, and (3) at least one compound which contains at least one labile halogen atom. U.S. Pat. No. 4,663,405 also discloses that the molecular weight of the polymers made with such catalyst systems can be reduced by conducting the polymerization in the presence of a vinyl halide. However, its teachings do not specifically disclose copolymerizations of isoprene with butadiene and do not provide any technique for making the isoprene monomer polymerize at a rate that is similar to that of the butadiene monomer. Thus, its teachings do not provide a technique for synthesizing random, non-tapered isoprene-butadiene rubbers with catalyst systems which are comprised of (1) an organoaluminum compound, (2) an organometallic compound which contains a metal from Group III-B of the Periodic System, such as lanthanides and actinides, and (3) at least one compound which contains at least one labile halogen atom.
[0004] U.S. Pat. No. 5,405,815 discloses a process or preparing a catalyst system which is particularly useful for copolymerizing isoprene and 1,3-butadiene monomers into rubbers which comprises the sequential steps of (1) mixing (a) an organoaluminum hydride, (b) a member selected from the group consisting of aliphatic alcohols, cycloaliphatic alcohols, aliphatic thiols, cycloaliphatic thiols, trialkyl silanols, and triaryl silanols, and (c) optionally, 1,3-butadiene in an organic solvent to produce a modified organoaluminum catalyst component; (2) adding an organometallic compound which contains a metal from Group III-B of the Periodic System to the modified organoaluminum catalyst component to produce a Group III-B metal containing catalyst component; (3) adding a compound which contains at least one labile halogen atom to the Group III-B metal containing catalyst component; and (4) aging the catalyst system after the compound which contains at least one labile halogen atom is added to the modified Group III-B metal containing catalyst component for a period of 10 minutes to 6 hours, wherein the catalyst system is aged at a temperature which is within the range of about 30° C. to about 85° C.
SUMMARY OF THE INVENTION
[0005] By utilizing the technique of this invention copolymers of isoprene and butadiene can be synthesized to higher molecular weights and higher cis-microstructure contents at faster polymerization rates. These copolymers also exhibit better processability and exhibit an excellent combination of properties for utilization in tire sidewall rubber compounds for truck tires. By utilizing these isoprene-butadiene rubbers in tire sidewalls, tires having improved cut growth resistance can be built without sacrificing rolling resistance. The isoprene-butadiene rubbers made by the process of this invention can also be employed in tire tread rubber compounds to improve the tread wear characteristics and decrease the rolling resistance of the tire without sacrificing traction characteristics.
[0006] The technique of this invention involves allowing the modified organoaluminum catalyst component and the organometallic compound that contains a metal from Group III-B of the Periodic System to react for at least 5 minutes before coming in contact with the labile halogen atom. The modified organoaluminum catalyst component and the organometallic compound that contains a metal from Group III-B of the Periodic System will typically be allowed to react at a temperature that is within the range of about 30° C. to about 100° C. for a period of about 5 minutes to about 25 minutes. The modified organoaluminum catalyst component will more typically be allowed to react with the Group III-B metal containing compound for a period of time that is within the range of about 15 minutes to about 20 minutes. In the practice of this invention it is convenient to add the compound that contains the labile halogen atom to the polymerization reactor as a separate component.
[0007] This invention more specifically discloses a process for the synthesis of isoprene-butadiene rubbers which comprises copolymerizing isoprene monomer and 1,3-butadiene monomer in an organic solvent in the presence of a catalyst system that is comprised of (I) a compound which contains at least one labile halogen atom and (II) a Group III-B metal containing catalyst component which is made by the sequential steps of (1) mixing (a) an organoaluminum hydride, (b) a member selected from the group consisting of aliphatic alcohols, cycloaliphatic alcohols, aliphatic thiols, cycloaliphatic thiols, trialkyl silanols, and triaryl silanols, and (c) optionally, 1,3-butadiene in an organic solvent to produce a modified organoaluminum catalyst component, and (2) adding an organometallic compound which contains a metal from Group III-B of the Periodic System to the modified organoaluminum catalyst component to produce a Group III-B metal containing catalyst component.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The relative amount of isoprene and butadiene, which can be copolymerized with the catalyst system of this invention, can vary over a wide range. For example, the monomer charge composition can contain from about 1 weight percent to about 99 weight percent butadiene and from about 1 weight percent to 99 weight percent isoprene. In most cases, the monomer charge composition will contain from about 10 weight percent to about 90 weight percent butadiene and from about 10 weight percent to 90 weight percent isoprene. It is normally preferred for the monomer charge composition to contain from about 25 weight percent to about 75 weight percent butadiene and from about 25 weight percent to about 75 weight percent isoprene. It is generally more preferred in the case of automobile tires for the monomer charge composition to contain from about 50 weight percent to about 75 weight percent butadiene and from about 25 weight percent to about 50 weight percent isoprene. It is generally more preferred in the case of truck tires for the monomer charge composition to contain from about 25 to 50 weight percent 1,3-butadiene and 50 to 75 weight percent isoprene.
[0009] The polymerizations of the present invention are carried out in a hydrocarbon solvent that can be one or more aromatic, paraffinic, or cycloparaffinic compounds. These solvents will normally contain from 4 to 10 carbon atoms per molecule and will be liquids under the conditions of the polymerization. Some representative examples of suitable organic solvents include pentane, isooctane, cyclohexane, normal hexane, benzene, toluene, xylene, ethylbenzene, and the like, alone or in admixture.
[0010] In solution polymerizations which utilize the catalyst systems of this invention, there will normally be from 5 to 35 weight percent monomers in the polymerization medium. Such polymerization mediums are, of course, comprised of an organic solvent, 1,3-butadiene monomer, isoprene monomer, and the catalyst system. In most cases, it will be preferred for the polymerization medium to contain from 10 to 30 weight percent monomers. It is generally more preferred for the polymerization medium to contain 12 to 18 weight percent monomers.
[0011] The catalyst system used in the process of this invention is made in a three-step process. In the first step, an organoaluminum hydride is mixed with an alcohol or a thiol and optionally, 1,3-butadiene. To attain good polymerization rates and high conversions, 1,3-butadiene will be mixed with the organoaluminum hydride and the alcohol or thiol in making the modified organoaluminum catalyst component. These three components (the organoaluminum hydride, the alcohol or thiol, and the 1,3-butadiene) can be mixed in any order. The organoaluminum hydride can be mixed with the alcohol or thiol in the presence of the 1,3-butadiene or the 1,3-butadiene can be added later. However, it is highly preferred to add the alcohol or thiol to the organoaluminum compound rather than adding the organoaluminum compound to the alcohol or thiol. This step is, of course, conducted in an inert organic solvent. Some representative examples of suitable inert organic solvents include pentane, isooctane, cyclohexane, normal hexane, benzene, toluene, xylene, ethylbenzene, and the like, alone or in admixture.
[0012] The molar ratio of the organoaluminum hydride to the alcohol or thiol will typically be within the range of about 3:2 to about 150:1. The molar ratio of the organoaluminum hydride to the alcohol or thiol will more typically be within the range of about 2:1 to about 100:1. As a general rule, it is more preferred for the molar ratio of the organoaluminum hydride to the alcohol or thiol to be within the range of about 5:2 to about 25:1. It is highly preferred for the ratio of the organoaluminum hydride to the alcohol or thiol to be within the range of about 3:1 to about 15:1.
[0013] It is not absolutely necessary to utilize any 1,3-butadiene in making the modified organoaluminum catalyst component. The molar ratio of the 1,3-butadiene to the organometallic compound which contains a metal from Group III-B of the Periodic System used in making the catalyst system will normally be greater than 3:1. The molar ratio of the 1,3-butadiene to the organometallic compound which contains a metal from Group III-B of the Periodic System used in making the catalyst system will typically be within the range of about 5:1 to about 100:1. The molar ratio of the 1,3-butadiene to the organometallic compound which contains a metal from Group III-B of the Periodic System used in making the catalyst system will more typically be within the range of about 10:1 to about 30:1. As a general rule, it is more preferred for the molar ratio of the 1,3-butadiene to the organometallic compound to be within the range of about 15:1 to about 25:1.
[0014] In this first step, a portion of the organoaluminum hydride is modified with the alcohol or thiol. However, it is important for there to be an excess of organoaluminum hydride because if all of it is modified, the catalyst system will not be active. The chemical reaction which takes place in cases where an alcohol is employed in the modification step can be depicted as follows:
[0015] wherein R represents an alkyl group. In cases where a silanol is used in the modification step, the reaction proceeds as follows:
[0016] wherein R represents an alkyl group. This reaction results in the formation of a modified organoaluminum catalyst component.
[0017] The organoaluminum hydrides which can be used have the structural formula:
[0018] wherein R 1 and R 2 can be the same or different and represent alkyl groups containing from 1 to about 12 carbon atoms. Normally R 1 and R 2 will represent alkyl groups which contain from about 2 to about 8 carbon atoms. More commonly, R 1 and R 2 will represent alkyl groups which contain about 3 to about 6 carbon atoms.
[0019] The alcohols and thiols which can be used include aliphatic alcohols, cycloaliphatic alcohols, aliphatic thiols, cycloaliphatic thiols, trialkyl silanols, and triaryl silanols. Virtually any aliphatic alcohol or cycloaliphatic alcohol can be employed. However, the alcohol will typically contain from 1 to about 12 carbon atoms. Alcohols which contain more than one hydroxyl group, such as diols, can also be used. Some representative examples of suitable alcohols include methanol, ethanol, normal-propyl alcohol, isopropyl alcohol, n-butyl alcohol, t-butyl alcohol, 1-pentanol, 1-hexanol, 1-hepthanol, 1-octanol, ethylene glycol, butane diol, and the like. Since 1-butanol (n-butyl alcohol) is soluble in many organic solvents, such as hexane, it is highly preferred.
[0020] Virtually any aliphatic thiol or cycloaliphatic thiol can be employed. However, the thiol will typically contain from 1 to about 12 carbon atoms. Thiols which contain more than one mercaptan group can also be used. The thiols which can be used typically have the structural formula R—SH wherein R represents an alkyl group or an aryl group containing from 1 to about 12 carbon atoms. Some representative examples of thiols which can be used include methyl mercaptan, ethyl mercaptan, n-propyl mercaptan, n-butyl mercaptan, t-butyl mercaptan, n-pentyl mercaptan, n-hexyl mercaptan, and the like.
[0021] The trialkyl silanols which can be used have the structural formula:
[0022] wherein R 1 , R 2 , and R 3 can be the same or different and represent alkyl groups which contain from 1 to about 12 carbon atoms. The triaryl silanols which can be used are generally of the structural formula:
[0023] wherein R 1 represents an aryl group which contains from 6 to 12 carbon atoms, and wherein R 2 and R 3 can be the same or different and represent alkyl groups containing from 1 to 12 carbon atoms or aryl groups which contain from 6 to 12 carbon atoms.
[0024] In the second step of the catalyst preparation procedure, a Group III-B metal containing organometallic compound is added to the modified organoaluminum catalyst component made in the first step. The modified organoaluminum catalyst component made in the first step is, of course, a mixture of both modified and unmodified organoaluminum hydride. The second step results in the formation of a Group III-B metal containing catalyst component. The molar ratio of the amount of the organometallic compound added to the amount of aluminum in the modified organoaluminum catalyst component will be within the range of about 1:6 to about 1:40. It is generally preferred for the molar ratio of the organolanthanide compound to the organoaluminum compound to be within the range of about 1:8 to about 1:25. It is normally more preferred for the molar ratio of the organolanthanide compound to the organoaluminum compound to be within the range of about 1:11 to about 1:20. Polymerization rates generally increase as the ratio of unreacted organoaluminum hydride (organoaluminum hydride which has not been modified with the alcohol or thiol) to the Group III-B metal containing organometallic compound increases. However, as the ratio of unreacted organoaluminum hydride to the organometallic compound is increased, the molecular weight and Mooney viscosity of the isoprene-butadiene rubber decreases.
[0025] The Group III-B metal containing organometallic compounds which can be employed may be symbolically represented as ML 3 wherein M represents the Group III-B metal and wherein L represents an organic ligand containing from 1 to about 20 carbon atoms. The Group III-B metal will be selected from the group consisting of scandium, yttrium, lanthanides, and actinides. It is normally preferred for the Group III-B metal to be a lanthanide. The organic ligand will generally be selected from the group consisting of (1) o-hydroxyaldehydes, (2) o-hydroxyphenones, (3) hydroxyesters, (4) β-diketones, (5) monocarboxylic acids, (6) ortho dihydric phenols, (7) alkylene glycols, (8) dicarboxylic acids, and (9) alkylated derivatives of dicarboxylic acids.
[0026] The lanthanides which can be used in the organolanthanide compound include lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The preferred lanthanide metals include cerium, praseodymium, neodymium, and gadolinium which have atomic numbers of 58, 59, 60, and 64, respectively. The most preferred lanthanide metal is neodymium.
[0027] In the organolanthanide compound utilized, the organic portion includes organic type ligands or groups which contain from 1 to 20 carbon atoms. These ligands can be of the monovalent and bidentate or divalent and bidentate form. Representative of such organic ligands or groups are (1) o-hydroxyaldehydes such as salicylaldehyde, 2-hydroxyl-1-naphthaldehyde, 2-hydroxy-3-naphthaldehyde and the like; (2) o-hydroxyphenones such as 2N-hydroxyacetophenone, 2N-o-hydroxybutyrophenone, 2N-hydroxypropiophenone and the like; (3) hydroxy esters such as ethyl salicylate, propyl salicylate, butyl salicylate and the like; (4) β-diketones such as acetylacetone, benzoylacetone, propionylacetone, isobutyrylacetone, valerylacetone, ethylacetylacetone and the like; (5) monocarboxylic acids such as acetic acid, propionic acid, valeric acid, hexanoic acid, 2-ethylhexanoic acid, neodecanoic acid, lauric acid, stearic acid and the like; (6) ortho dihydric phenols such as pyrocatechol; (7) alkylene glycols such as ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol and the like; (8) dicarboxylic acids such as oxalic acid, malonic acid, maleic acid, succinic acid, o-phthalic acid and the like; and (9) alkylated derivatives of the above-described dicarboxylic acids.
[0028] Representative organolanthanide compounds corresponding to the formula ML 3 , which may be useful in this invention include cerium acetylacetonate, cerium naphthenate, cerium neodecanoate, cerium octanoate, tris-salicylaldehyde cerium, cerium tris-8-hydroxyquinolate), gadolinium naphthenate, gadolinium neodecanoate, gadolinium octanoate, lanthanum naphthenate, lanthanum octanoate, neodymium naphthenate, neodymium neodecanoate, neodymium octanoate, praseodymium naphthenate, praseodymium octanoate, yttrium acetylacetonate, yttrium octanoate, dysprosium octanoate, and other lanthanide metals complexed with ligands containing from 1 to about 20 carbon atoms.
[0029] The actinides which can be utilized in the Group III-B metal containing organometallic compound include actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, and lawrencium. The preferred actinides are thorium and uranium which have atomic numbers of 90 and 92, respectively. Some representative examples of organoactinides which can be employed include tris(π-allyl) uranium chloride, tris(π-allyl) uranium bromide, tris(π-allyl) uranium iodide, uranium tetramethoxide, uranium tetraethoxide, uranium tetrabutoxide, uranium octanoate, thorium tetraethoxide, tris(π-allyl) thorium chloride, thorium naphthenate, uranium isovalerate, thorium octanoate, tris(π-allyl) thorium bromide, tris(π-allyl) thorium iodide, thorium tetramethoxide, and the like.
[0030] After the Group III-B metal ontaining compound is added, it is preferred to “age” the Group III-B metal containing catalyst component at a temperature which is within the range of about 30° C. to about 100° C. for a period of about 5 minutes before use. It is generally more preferred to age the Group III-B metal containing catalyst component at a temperature which is within the range of about 30° C. to 85° C. and it is typically most preferred to age the catalyst system at a temperature which is within the range of about 40° C. to about 65° C. It is more preferred to age the Group III-B metal containing catalyst system for a period of about 5 minutes to about 25 minutes with it being most preferred to age the Group III-B metal containing catalyst component for a period of 15 minutes to about 25 minutes.
[0031] In the third and final step of the catalyst preparation procedure a compound which contains at least one labile halogen atom is added. This can be accomplished by simply adding the Group III-B metal containing catalyst component and the compound that contains a labile halogen atom to a polymerization medium as separate components. This can be done by simply adding the Group III-B metal containing catalyst component and the compound that contains a labile halogen atom as separately to the polymerization medium that contains the isoprene, the 1,3-butadiene, and the organic solvent. In an alternative embodiment of this invention, the Group III-B metal containing catalyst component and the compound that contains a labile halogen atom can be mixed prior to the time that they are introduced into the reactor. However, it is critical for the organometallic compound that contains a Group III-B metal and the modified organoaluminum compound to reacted to produce the Group III-B metal containing catalyst component before coming in contact with the compound that contains the labile halogen atom.
[0032] The catalyst system will typically be added at a level sufficient to provide from 0.05 to 0.5 millimoles of the Group III-B metal per 100 grams of total monomer. More typically, the catalyst system will be added in an amount sufficient to provide from 0.25 to 0.35 millimoles of the Group III-B metal per 100 grams of total monomer. Its use results in the formation of an essentially non-tapered, random isoprene-butadiene rubber that has excellent characteristics for use in making tires. This is due to the fact that the modification procedure causes the catalyst system to polymerize the butadiene monomer at a rate that is only about 1.2 times to 1.5 times faster than the rate of isoprene polymerization. It should be noted that in cases where the organoaluminum hydride is not modified with a thiol or an alcohol, the butadiene monomer polymerizes at a rate which is about 20 times faster than the rate at which the isoprene polymerizes.
[0033] The molar ratio of the amount of the compound containing the labile halogen atom added to the Group III-B metal in the Group III-B metal containing catalyst component will normally be within the range of about 1:1 to about 5:1. It is generally preferred for the molar ratio of the labile halogen atom containing compound to the Group III-B metal to be within the range of about 3:2 to about 3:1. It is normally more preferred for the ratio of the labile halide containing compound to the lanthanide metal in the lanthanide containing compound component to be within the range of 1.8:1 to about 5:2.
[0034] The labile halogen atom containing compound will normally contain a labile bromine atom, chlorine atom, fluorine atom, or iodine atom. A combination of two or more of these labile halogen atoms in the same or different compounds can also be utilized. These halogen atoms can be introduced as (1) tertiary alkyl halides; (2) secondary alkyl halides; (3) aralkyl halides; (4) allyl halides; (5) hydrogen halides; (6) alkyl, aryl, alkaryl, aralkyl and cycloalkyl metal halides wherein the metal is selected from the Groups II, III-A and IV-A of the Periodic Table; (7) metallic halides, such as halides of metals of Groups III, IV, V, VI-B and VIII of the Periodic Table; (8) halosilanes; (9) halosulfides; (10) halophosphines; and (11) organometallic halides corresponding to the general formula ML (3-y) Xy wherein M is a metal selected from the group consisting of metals of Group III-B of the Periodic Table having atomic numbers of 21, 39, and 57 through 71 inclusive; L is an organic ligand containing from 1 to 20 carbon atoms and selected from the group consisting of (a) o-hydroxyaldehydes, (b) o-hydroxyphenones, (c) hydroxyquinolines, (d) β-diketones, (e) monocarboxylic acids, (f) ortho dihydric phenols, (g) alkylene glycols, (h) dicarboxylic acids, (i) alkylated derivatives of dicarboxylic acids and (j) phenolic ethers; X is a halogen atom and y is an integer ranging from 1 to 2 and representing the number of halogen atoms attached to the metal M. The organic ligand L may be of the monovalent and bidentate or divalent and bidentate form.
[0035] Representative examples of such compounds containing labile halogen atoms include (1) inorganic halide acids, such as hydrogen bromide, hydrogen chloride and hydrogen iodide; (2) organometallic halides, such as ethylmagnesium bromide, butylmagnesium bromide, phenylmagnesium bromide, methylmagnesium chloride, butylmagnesium chloride, ethylmagnesium iodide, phenylmagnesium iodide, diethylaluminum bromide, diisobutylaluminum bromide, methylaluminum sesquibromide, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, diisobutylaluminum chloride, isobutylaluminum dichloride, dihexylaluminum chloride, cyclohexylaluminum dichloride, phenylaluminum dichloride, didodecylaluminum chloride, diethylaluminum fluoride, dibutylaluminum fluoride, diethylaluminum iodide, dibutylaluminum iodide, phenylaluminum diiodide, trimethyltin bromide, triethyltin chloride, dibutyltin dichloride, butyltin trichloride, diphenyltin dichloride, tributyltin iodide and the like; (3) inorganic halides such as aluminum bromide, aluminum chloride, aluminum iodide, antimony pentachloride, antimony trichloride, boron tribromide, boron trichloride, ferric chloride, gallium trichloride, molybdenum pentachloride, phosphorus tribromide, phosphorus pentachloride, stannic chloride, titanium tetrachloride, titanium tetraiodide, tungsten hexachloride and the like; and (4) organometallic (Group III-B) halides, such as t-butyl-salicylaldehydrocerium (III) chloride, salicylaldehydrocerium (III) chloride, 5-cyclohexylsalicylaldehydrocerium (III) chloride, 2-acetylphenolatocerium (III) chloride, oxalatocerium (III) chloride, oxalatocerium (III) bromide and the like; (5) tertiary alkyl halides, such as t-butyl bromide and t-octyl bromide; (6) secondary alkyl halides, such as isopropyl bromide and isopropyl chloride; (7) aralkyl halides, such as benzyl bromide and bromomethyl naphthalene; and (8) allyl halides, such as allyl bromide, 3-chloro-2-methylpropene, 1-bromobutene-2, and 1-bromopentene-2. The preferred compounds which contain labile halogen atoms are benzyl halides and allyl halides.
[0036] The polymerization temperature utilized can vary over a broad range of from about 0° C. to about 125° C. In most cases a temperature within the range of about 30° C. to about 85° C. will be utilized. Temperatures within the range of about 50° C. to about 75° C. are generally the most preferred polymerization temperatures. The pressure used will normally be sufficient to maintain a substantially liquid phase under the conditions of the polymerization reaction.
[0037] The polymerization is conducted for a length of time sufficient to permit substantially complete polymerization of monomers. In other words, the polymerization is normally carried out until high conversions are attained. The polymerization can then be terminated using a standard technique.
[0038] The isoprene-butadiene rubbers, which are made by utilizing the techniques of this invention in solution polymerizations, can be recovered utilizing conventional techniques. It may be desirable to add antioxidants to the polymer solution in order to protect the isoprene-butadiene rubber produced from potentially deleterious effects of contact with oxygen. The isoprene-butadiene rubber made can be precipitated from the polymer solution. The styrene-isoprene rubber made can also be recovered from the solvent and residue by means such as decantation, filtration, centrification, and the like. Steam stripping can also be utilized in order to remove volatile organic compounds from the rubber.
[0039] The isoprene-butadiene rubbers made by the technique of this invention will typically have a glass transition temperature which is within the range of about −65° C. to about −110° C. Such isoprene-butadiene rubbers will also generally have a Mooney viscosity that is within the range of about 50 to about 120. The isoprene-butadiene rubber will more typically have a Mooney viscosity that is within the range of 70 to 100.
[0040] The isoprene-butadiene rubbers made by the technique of this invention can be blended with other sulfur-vulcanizable rubbers to make compounds which have excellent characteristics for use in tire treads. For instance, improved rolling resistance and treadwear characteristics can be attained without sacrificing wet or dry traction characteristics. The isoprene-butadiene rubbers of this invention will normally be blended with other polydiene rubbers in making tire tread compounds. More specifically, the isoprene-butadiene rubber can be blended with natural rubber, high cis-1,4-polybutadiene, medium vinyl polybutadiene (having a glass transition temperature which is within the range of −10° C. to −40° C.), synthetic 1,4-polyisoprene, 3,4-polyisoprene (having a glass transition temperature which is within the range of −10° C. to −45° C.), styrene-butadiene rubbers (having a glass transition temperature which is within the range of 0° C. to −80° C.) and styrene-isoprene-butadiene rubbers (having a glass transition temperature which is within the range of −10° C. to −80° C.) to make useful tire tread compounds. A highly preferred blend for utilization in tire treads includes natural rubber, 3,4-polyisoprene rubber and the isoprene-butadiene rubber of this invention.
[0041] Various blend ratios can be employed in preparing tire tread compounds which exhibit a highly desirable combination of traction, rolling resistance, and tread wear characteristics. Another specific blend which is highly advantageous for utilization in tire tread compounds is comprised of about 40 weight percent to about 60 weight percent styrene-isoprene-butadiene rubber having a glass transition temperature which is within the range of about −70° C. to about −80° C. and from about 40 weight percent to about 60 weight percent of the isoprene-butadiene rubber prepared in accordance with the process of this invention.
[0042] This invention is illustrated by the following examples which are merely for the purpose of illustration and are not to be regarded as limiting the scope of the invention or the manner in which it can be practiced. Unless specifically indicated otherwise, parts and percentages are given by weight.
EXAMPLE 1
[0043] In this experiment an isoprene-butadiene rubber was synthesized by the technique of this invention. In the procedure employed a one gallon (3.78 liter) reactor was charged with 1000 grams of a dry hexane solution containing 81.9 grams of 1,3-butadiene followed by 663 grams of 1.2 molar diisobutylaluminum hydride (DIBAH) in hexane (25 weight percent DIBAH). Then, a solution containing 21.5 grams of triphenylsilanol dissolved in 260 grams of toluene was charged into the reactor at a temperature of 18° C. and the contents of the reactor. After stirring for 40 minutes, a solution of 105.4 grams of 10.3% neodymium solution (as neodymium neodecanoate), diluted with 165 grams of dry hexane, was charged into the reactor. The solution was allowed to stir for one hour after which 19.1 grams of allylbromide was added. The cooling was stopped and the solution allowed to warm up to ambient temperatures. After stirring for about 90 minutes, the catalyst solution was heat aged at 65° C. for 1-2 hours. The aged catalyst solution was then cooled and stored in a dry container under nitrogen.
[0044] Then, 15.6 ml of the 0.025 molar aged neodymium catalyst solution (lanthanide containing catalyst component) was added to a solution containing 130 grams of isoprene and 130 grams of 1,3-butadiene in 1610 grams of dry hexane in a one gallon (3.78 liter) reactor under nitrogen at a temperature of 65° C. The polymerization was carried out with stirring for 3 hours. Periodically during the polymerization, samples of the polymerization solution were coagulated in a 60/40 volume percent mixture of ethanol/decane. The coagulated polymer was allowed to settle at −20° C. followed by gas chromatographic analysis of the supernatant liquid to determine the residual monomer content. Subtraction from the initial monomer concentrations allowed calculation of the individual monomer conversions. These analyses showed that the incorporation of butadiene to isoprene in the polymer was 3 to 2 by weight indicating the formation of a highly random, essentially non-tapered isoprene-butadiene rubber.
COMPARATIVE EXAMPLE 2
[0045] In this experiment the copolymerization of Example 1 was repeated using a standard neodymium catalyst system (DIBAH/Nd/Allylbromide/Bd: 15/1/2/20 molar ratios) without the silanol modification of this invention. Gas chromatographic analyses of the residual monomers, as described in Example 1, showed the incorporation of butadiene to isoprene in the polymer was approximately 19 to 1 by weight, indicating the formation of a considerably less random, highly tapered copolymer.
EXAMPLE 3
[0046] In this experiment, an isoprene-butadiene copolymer rubber was prepared using an alcohol modified neodymium catalyst system. In this procedure, a one gallon (3.78 liter) reactor was charged with 1,214 grams of hexane containing 81.3 grams of butadiene and 558.43 grams of 1.23 molar diisobutylaluminum hydride (DIBAH) in hexane, (i.e., 25% weight percent DIBAH). The reactor was maintained at 20° C. by cooling. N-butanol (11.16 grams) was added with stirring. After stirring for thirty minutes, 107.5 grams of 10.1% neodymium solution (neodymium neodecanoate) diluted with 160 grams of dry hexane, was charged to the reactor. The solution was stirred for another thirty minutes after which time 18.2 grams of allyl bromide was added. The cooling was stopped and the solution was allowed to warm up. A delayed exothermic reaction was noted. After twenty minutes, bring the solution temperatures to about 10° C. above ambient temperature. When the temperature ultimately dropped, the catalyst solution was aged by heating at 65° C. for ninety minutes. The catalyst prepared had a [butanol-DIBAH]Nd-allyl bromide-butadiene molar ratio of [2-13]-1-2-20, respectively, and a concentration of 0.025 molarity with respect to the neodymium.
[0047] To a solution of 128.6 grams of isoprene and 129 grams of dry hexane in a one gallon (3.79 liter) reactor under nitrogen at 65° C., was added 20.7 milliliters (0.2 mmoles of neodymium/100 grams of total monomer [Bd+Ip]) of the above prepared catalyst. The polymerization was carried out with stirring for two hours and twenty minutes. Samples were taken during the polymerization as described in Example 1. Analyses of the samples showed that the incorporation of butadiene to isoprene (measured at low conversion) was 1.4/1 by weight indicating formation of a highly random, non-tapered isoprene-butadiene rubber. The yield was 87%. The Mooney of the dried rubber was 87; the Tg was −97° C.
EXAMPLE 4
[0048] In this experiment, an isoprene-butadiene copolymer was synthesized using an alcohol modified neodymium catalyst system with a different catalyst component molar ratio than that described in Example 3. In this procedure, a one gallon (3.78 liter) reactor was charged with 1,088 grams of hexane containing 93.5 grams of butadiene and 668 grams of 1.23 molar diisobutylaluminum hydride (DIBAH) in hexane (i.e., 25% weight percent DIBAH). To this solution was added 26.22 grams of n-butanol with stirring and with temperatures maintained at 20EC. After stirring for thirty minutes, 107.5 grams of a 10.1% neodymium solution (neodymium neodecanoate), dilute with 158 grams of dry hexane, was charged to the reactor. The solution was stirred for another thirty minutes after which time 21.4 grams of allyl bromide was added. The cooling was stopped and the mixture allowed to warm up to ambient (and above) temperature. After the exotherm subsided, requiring about one hour, the catalyst solution was heat aged at 65° C. for ninety minutes. The aged catalyst was then cooled and stored in a dry container under nitrogen. The catalyst prepared had a [butanol-DIBAH] Nd-allyl bromide-butadiene molar component ratio of [4.7-15.5]-1-2.35-23, respectively, and a concentration of 0.025 molarity with respect to the neodymium.
[0049] Using the method described in Examples 1 and 3, a solution of 128 grams of isoprene and 128 grams of butadiene in 1,579 grams of dry hexane was polymerized using 29.6 milliliters of the above prepared catalyst. Samples of the polymerization batch at different time intervals showed a butadiene to isoprene incorporation ratio (measured at low conversion) of 1.35/1. After two hours and ten minutes, an 88% yield of the copolymer was obtained. A Mooney viscosity of the dried copolymer was 97 and its the Tg was −90° C.
EXAMPLE 5
[0050] In this experiment, an isoprene-butadiene copolymer was synthesized using an alcohol modified neodymium catalyst system modified with 1,4-butanediol. In this procedure, a one gallon (3.78 liter) reactor was charged with 1,093 grams of hexane containing 81.9 grams of butadiene and 663 grams of 1.2 molar diisobutylaluminum hydride (DIBAH) in hexane (i.e., 25% weight percent DIBAH). To this solution was then added 6.78 grams of 1,4-butanediol with stirring and with temperatures maintained at 20° C. The suspension of the butanediol gradually dissolved upon reacting with the DIBAH. After one hour of stirring, 105.4 grams of a 10.3% neodymium solution (neodymium neodecanoate), diluted with 165 grams of hexane, was added to the reactor. The solution was stirred for another thirty minutes after which time 19.1 grams of allyl bromide was added. The cooling was stopped and the mixture allowed to warm up to ambient (and above) temperature. After the exotherm subsided, the catalyst solution was aged by heating at 65° C. for ninety minutes. The catalyst prepared had a [butanediol-DIBAH]-ND-allyl bromide-butadiene molar component ratio of [1-16]-1-2-20, respectively, and a concentration of 0.025 molarity with respect to the neodymium. The aged catalyst was then cooled and stored in a dry container under nitrogen.
[0051] Using the polymerization procedure described in the earlier examples, 123 grams of isoprene and 124 grams of butadiene in 1,546 grams of dry hexane was polymerized using 14.2 milliliters of the above prepared catalyst. Analyses of samples taken during the polymerization show the ratio of the incorporation of butadiene to isoprene (measured at low conversion) was 1.44/1. A yield of 87% was obtained after 130 minutes.
EXAMPLE 6
[0052] In this experiment, an isoprene-butadiene copolymer rubber was prepared using another rare earth metal, praseodymium. In the procedure employed, a one gallon (3.78 liter) reactor was charged with 1,000 grams of a dry hexane solution containing 82 grams of 1,3-butadiene, followed by 663 grams of a 1.2 molar diisobutylaluminum hydride (DIBAH) in hexane. A solution of 21.5 grams triphenylsilanol dissolved in 250 grams of toluene was then charged into the reactor at a temperature of 20° C. After stirring for about forty minutes, 85.9 grams of a 0.826 molar solution of praseodymium octoate, diluted with 195 grams of hexane, was charged to the reactor. The solution was allowed to stir for forty-five minutes after which 19.1 grams of allyl bromide was added. The cooling was stopped and the mixture was allowed to warm up to ambient temperature (and above). After stirring for about one hour, the catalyst system was aged by heating at 65° C. for ninety minutes. The catalyst prepared had a [silanol-DIBAH]-Pr-allyl bromide-butadiene component molar ratio of [1-15]-1-2-20, respectively, and a concentration of 0.025 molarity with respect to the neodymium. The aged catalyst was then cooled and stored in a dry container under nitrogen.
[0053] Using the polymerization procedure described in Examples 1 and 3, 124 grams of isoprene and 125 grams of butadiene in 1,439 grams of dry hexane were polymerized using 19.6 milliliters of the above praseodymium-based catalyst. Samples of the polymerization solution during the run showed that the rate of incorporation of the butadiene to isoprene (measured at low conversion) was 1.7/1 by weight. A yield of 37% was obtained after one hour and forty minutes. The Mooney of the dried sample was 64 and its Tg was −96° C.
COMPARATIVE EXAMPLE 7
[0054] In this experiment, the copolymerization of Example 6 was repeated with a praseodymium-based catalyst prepared as described in Example 6 except without the triphenylsilanol modifier.
[0055] Analyses of the samples of the copolymerization showed that the rate of incorporation of the butadiene to isoprene (measured at low conversion) was 16/1 by weight, indicating formation of a somewhat tapered copolymer, in contrast to the highly random copolymer formed when the triphenylsilanol catalyst modifier was employed.
[0056] While certain representative embodiments and details have been shown for-the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. | The subject invention relates to a technique for synthesizing rubbery non-tapered, random, copolymers of 1,3-butadiene and isoprene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire sidewall rubber compounds for truck tires. By utilizing these isoprene-butadiene rubbers in tire sidewalls, tires having improved cut growth resistance can be built without sacrificing rolling resistance. Such rubbers can also be employed in tire tread compounds to improve tread wear characteristics and decrease rolling resistance without sacrificing traction characteristics. This invention more specifically discloses a process for the synthesis of isoprene-butadiene rubbers which comprises copolymerizing isoprene monomer and 1,3-butadiene monomer in an organic solvent in the presence of a catalyst system that is comprised of (I) a compound which contains at least one labile halogen atom and (II) a Group III-B metal containing catalyst component which is made by the sequential steps of (1) mixing (a) an organoaluminum hydride, (b) a member selected from the group consisting of aliphatic alcohols, cycloaliphatic alcohols, aliphatic thiols, cycloaliphatic thiols, trialkyl silanols, and triaryl silanols, and (c) optionally, 1,3-butadiene in an organic solvent to produce a modified organoaluminum catalyst component, and (2) adding an organometallic compound which contains a metal from Group III-B of the Periodic System to the modified organoaluminum catalyst component to produce a Group III-B metal containing catalyst component. | 2 |
CROSS REFERENCE TO RELATED PATENTS
[0001] This application claims priority to provisional patent application Ser. No. 61/079,302 filed on Jul. 9, 2008 entitled “Rail Car Door Closer” by Carl A. Register.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to rail car door closures and, more particularly, to rail car door closures that are attached to opposite ends of a rotating axle with an actuating mechanism that is attached to and covered by an elongated main frame tent structure with cam closures for pressing against the rail car door to cause the rail car door to close during rotation of the axle.
[0004] 2. Background of the Prior Art
[0005] Railroad cars are used to carry bulk commodities with the most common bulk commodity being coal to provide energy and power. Other bulk commodities may be grain, aggregate, phosphate or other similar type materials. The railroad car used to carry bulk commodities normally has hopper doors on the bottom thereof that swing downward when unloading. These hopper doors on the bottom of a railroad car typically weigh about 200-300 pounds each and are difficult to close manually even under ideal conditions. After a period of extended wear, the hopper doors may become bent or warped making the closing of the hopper doors manually even more difficult.
[0006] Over the years, numerous injuries to railroad workers have been involving the closing of the heavy hopper doors. The manual closing of the hopper doors takes two people under even ideal conditions. A warped, bent or worn hopper door becomes even more difficult to close.
[0007] U.S. Pat. No. 6,886,473 to Marchiori et al shows a type of rail car door closure having a chain drive or cable with a rotatable member attached thereto. By turning the rotatable member into the upper direction, followed by forward and reverse motion of the chain or cable, rail car doors are closed by force exerted against the door from the rotatable member. However, the system as shown in Marchiori et al has certain limitations involving primarily the installation and maintenance of the mechanism.
[0008] A different version of a door car opener and closer is shown in U.S. Pat. No. 7,063,022 to Marchiori et al that is a fairly complicated rail car door opener and closer combination. The opener portion is not applicable to the present invention and will only work on certain types of door locks. The system as shown in the '022 patent can only be installed at locations that provide enough clearance from the railroad track to install and operate the system.
[0009] Another type of rail car door closure is shown in U.S. Pat. No. 7,178,464 to Clarke. The system as shown in Clarke has a bell crank assembly which actuates arms that press against the hopper door to cause closure thereof.
[0010] U.S. Pat. No. 5,419,262 to Turpin, Sr. shows a railroad hopper car door closure with wheels mounted on the end of a pair of laterally extending arms to cause closure of the hopper doors. The system as shown in Turpin is located outside the railroad tracks and is not protected from falling bulk commodity.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to provide a simple, safe, cost effective, but reliable, rail car door closure.
[0012] It is another object of the present invention to provide a rail car door closure that has an axle with a cam mounted thereon so that rotating the axle forces the cam against the rail car door forcing the rail car door up to the closed and locked position.
[0013] It is yet another object of the present invention to provide a rail car door closure that is operated by a pneumatic or hydraulic cylinder.
[0014] It is yet another object of the present invention to have a series of rail car door closures for simultaneously closing multiple hopper doors for a single railroad car simultaneously.
[0015] It is still another object of the present invention to provide multiple door closures for simultaneously closing hopper doors by rotation in one direction and, sequentially thereafter, closing mating hopper doors by a rotation of door closures in the opposite direction.
[0016] In the present invention, the actuated mechanisms of the rail car door closure is located between the railroad tracks at the place for dumping the bulk commodity. A tent type structure protects the actuating mechanism from falling bulk commodity. A pair of axles extend from the tent structure to either side thereof. On each end of the pair of axles are located closure arms.
[0017] A hydraulic cylinder is used to rotate a first axle and a first pair of closure alms on each end thereof. Sequentially thereafter, a second hydraulic cylinder rotates a second axle with a second pair of closure arms thereon. In this manner, a first hopper door is closed and then the mating hopper door (if there is one) is subsequently closed.
[0018] The actuation of the hydraulic cylinders is controlled by a control box. The hydraulic cylinders may be actuated in any manner desired depending upon the particular railroad car being unloaded and the hopper doors located thereon. This may vary from railroad car to railroad car.
[0019] Also, additional pairs of axles and closure arms can be included with additional pairs of hydraulic cylinders if more than one set of hopper doors are to be closed at one time. This varies according to the preference of the particular operator or the type railroad cars being unloaded.
[0020] The axles are supported by flange bearings attached to the tent type frame. The ends of the hydraulic cylinders are held in clevises. Keys and key ways are used to attach to the respective axles. A slotted connector arms provides for ease of connection of the cylinders to each axle to cause rotation movement thereof Also, the slotted converter arms may be quickly disconnected and removed for maintenance or repair.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a pictorial block diagram of the controls for the rail car door closure showing the present invention.
[0022] FIG. 2 is an elevated side view of the rail car door closure installed below a railroad car, but with the structure being cut away.
[0023] FIG. 3 is a sequential view of FIG. 2 .
[0024] FIG. 4 is a sequential view of FIGS. 2 and 3 .
[0025] FIG. 5 is a bottom view of the rail car door closure.
[0026] FIG. 6 is an explotive perspective view of one axle of the rail car door closure.
[0027] FIG. 7 is a top view of the rail car door closure as installed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Referring to FIGS. 1 and 2 in combination, the rail car door closure system will be explained in further detail. A rail road car 10 that carries bulk commodities will typically have a hopper 12 at the bottom thereof that may be closed by hopper doors 14 and 16 hinged thereto. The rail road car 10 is supported by flanged wheels 18 that run on railroad tracks 20 . A space 22 is provided below the hopper 12 into which a bulk commodity (not shown) being hauled in the railroad car 10 can be dumped. Across the space 22 , the railroad tracks 20 can be supported by suitable structural support such as I beams (not shown).
[0029] Located adjacent to the railroad tracks 20 as shown in FIG. 1 is a control box 24 and a pressure source 26 to provide pressurized fluid or hydraulics. From the pressure source 26 , pressurized fluid is provided by hydraulic lines 28 and 30 to control valves 32 and 34 , respectively. Control valve 32 provides hydraulic fluid via hydraulic lines 36 and 38 to and from first hydraulic cylinder 40 .
[0030] Extending from the first hydraulic cylinder 40 is a first hydraulic cylinder arm 42 that connects to a first slotted connector arm 44 . Because the first slotted connector arm 44 is rigidly connected to first axle 46 , as the first hydraulic cylinder arm 42 extends or contracts, first slotted connector arm 44 extends or contracts and hence rotates first axle 46 . On each end of first axle 46 are located first cam closures 48 . As the first axle 46 rotates, first cam closures 48 will also rotate because they are rigidly attached to the first axle 46 .
[0031] Referring now to control valve 34 , hydraulic lines 50 and 52 provide hydraulic fluid to and from second hydraulic cylinder 54 . Second hydraulic cylinder 54 extends second hydraulic cylinder arm 56 that is pivotally connected to a second slotted connector arm 58 . Because the second slotted connector arm 58 is rigidly connected to second axle 60 , second axle 60 rotates as the second slotted connector arm 58 rotates due to action of the second hydraulic cylinder arm 56 .
[0032] On each end of second axle 60 is located second cam closures 62 . The second cam closures are rigidly attached to each end of second axle 60 so that as second axle 60 rotates, second cam closures also rotate.
[0033] Referring now to FIG. 2 , the first cam closure 48 and second cam closures 62 are in the relaxed position. First hydraulic cylinder 40 and second hydraulic cylinder 54 are likewise relaxed so that first hydraulic cylinder arm 42 and second cylinder arm 56 are not extended, but are in their full relaxed state. However, upon activation of first hydraulic cylinder 40 , first hydraulic cylinder arm 42 extends causing rotation about the first axle 46 . Likewise, when second hydraulic cylinder 54 is activated and second hydraulic cylinder arm 56 is extended, rotation will occur second axle 60 .
[0034] While cut away for illustration purposes, a tent frame structure 64 protects the first hydraulic cylinder 40 and second hydraulic cylinder 54 from falling bulk commodities or material.
[0035] Referring now to FIGS. 3 and 4 in sequence, FIG. 3 illustrates first hydraulic cylinder 40 has been activated via control valve 32 (see FIG. 1 ) so that first hydraulic cylinder arm 42 is extended. The first hydraulic cylinder arm 42 pushes against one end of the first slotted connector arm 44 which causes rotation of the first axle 46 . Rotation of the first axle 46 rotates the first cam closures 48 on either end thereof which presses against hopper door 14 pushing it into a closed position.
[0036] While many different types of latches are used to maintain hopper doors on railroad cars in a closed position, a typical such lock is a Wine door lock that is commonly used in the industry. Other types of door latches are also used. The particular door latches are not shown, but when hopper door 14 is pushed against the hopper 12 as shown in FIG. 3 , the door latch (not shown) will hold the hopper door 14 in the closed position.
[0037] Referring now to FIG. 4 , after the hopper door 14 has been closed, second hydraulic cylinder 54 is activated by control valve 34 (see FIG. 1 ) so that second hydraulic cylinder arm 56 is extended. As second hydraulic cylinder arm 56 extends, it causes second slotted connector arm 58 to rotate causing pivotal rotation of second axle 60 to which it is connected. Rotation of second axle 60 pivots the cam closure 62 on either end thereof to press against the hopper door 16 and push hopper door 16 to the closed position. Hopper door 16 on the hopper 12 as illustrated in FIG. 4 overlaps hopper door 14 . Therefore, hopper door 14 must be closed first and hopper door 16 closed second. Again, while the particular latching mechanism is not shown, a Wine door lock which is common in the industry could be used to hold hopper doors 14 and 16 in the closed position.
[0038] Referring now to FIG. 5 and 6 in combination, the hydraulic control portion of the present invention will be explained in further detail. FIG. 5 is a bottom view of the hydraulic control portion as shown in FIG. 2 . The tent frame structure 64 which is an elongated tent shape extends over first hydraulic cylinder 40 and second hydraulic cylinder 54 . For purposes of illustration, hydraulic lines 36 and 38 are cut away from hydraulic cylinder 40 and hydraulic lines 50 and 52 are cut away from second hydraulic cylinder 54 .
[0039] Referring to first hydraulic cylinder 40 , it is attached by clevis pin 66 to mounting bracket 68 so that the first hydraulic cylinder 40 can rotate about the clevis pin 66 . As the first hydraulic cylinder 40 receives hydraulic fluid thereto, the first hydraulic cylinder arm 42 is extended. A shackle 70 on the end of first hydraulic cylinder arm 42 connects via clevis pin 72 to the first slotted connector arm 44 . The first slotted connector arm 44 is rigidly attached to first axle 46 with axle clamp 74 (see FIG. 6 ). Axle clamp 74 has a suitable set screw (not shown) for connecting into slot 76 of first axle 46 . By bolting the first slotted connector arm 44 to the axle clam 74 , rotation of the first slotted connector arm 44 will cause rotation of first axle 46 .
[0040] Mounted on either side of the tent frame structure 64 are flange bearings 78 and 80 . The first axle 46 extends through holes (not shown) in tent frame structure 64 and through flange bearings 78 and 80 . The flange bearings 78 and 80 are used to provide support for the rotation of first axle 46 .
[0041] Mounted on each end of the first axle 46 are the first cam closures 48 which are bolted to retaining rings 82 and 84 . Retaining rings 82 and 84 are secured to first axle 46 by means of set screws (not shown) that connect into retaining ring slots 86 and 88 , respectively of first axle 46 . The retaining ring slots 86 and 88 will prevent the first cam closures 48 from working their way off of the first axle 46 .
[0042] While not shown in detail, the second axle 60 operates the same as the first axle 46 shown in the exploded perspective view of FIG. 6 , but rotates in the opposite direction. When second hydraulic cylinder 54 is activated by control valve 34 , second hydraulic cylinder arm 56 is extended. One end of second hydraulic cylinder 54 is held into position by clevis pin 90 pivotally attached to mounting bracket 92 . On the far end of second hydraulic cylinder arm 56 is a shackle 94 through which clevis pin 96 pivotally attaches to the second slotted connector arm 58 . Since the rotation of the second axle 60 via the second slotted connector arm 58 is essentially the same as that previously described for first axle 46 and illustrated in FIG. 6 , it will not be covered in further detail herein. The rotation of the second axle 60 will rotate the second cam closures 62 secured to either end thereof.
[0043] Referring now to FIG. 7 an overhead view of the present invention is illustrated with the railroad car 10 removed. The railroad tracks 20 extend over the space 22 into which the bulk material is dumped. I-beams or other support may be provided across this space 22 to support the railroad tracks 20 .
[0044] Located between the railroad tracks 20 is the tent frame structure 64 which deflects the bulk material such as coal or other aggregates from hitting the first hydraulic cylinder 40 or the second hydraulic cylinder 54 (not visible in FIG. 7 ) as the bulk material falls into space 22 . To close the hopper doors of any railroad car that may be moved above space 22 and the material dumped therein, first cam closures 48 will be rotated upward against the hopper door. After closing the first hopper door, then if the railroad car has a second hopper door, it will be closed by rotating upward the second cam closures 62 . By use of the invention as just described, many different types of hopper doors for railroad cars can be closed. If it is a single door hopper, then the appropriate cam closures 48 or 62 will be rotated upward by the operator pushing the appropriate buttons (not shown) in a control box 24 .
[0045] By use of the rail car door closure as described in the present invention, it is not critical that the railroad car be in the exact location. The railroad car can be off by a foot or two and still be closed by use of the present invention.
[0046] While the present invention is illustrated with a single set of hopper doors for a railroad car, most railroad cars have multiple sets of hopper doors. In such case, additional sets of hydraulic cylinders and cam closures could be added for each additional set of hopper doors. For the purposes of simplicity, the present invention was illustrated with only one set of hopper doors. However, it could equally be utilized with multiple sets of dual hopper doors or multiple sets of single door hoppers.
[0047] The present invention has everything located below the railroad tracks except the control box that can be operated to the side thereof, or to any other location that may be desired by the person unloading the railroad cars. The present invention is very durable and can be utilized with all types of bulk materials or aggregates regardless of how abrasive or dusty. | A rail car door closer is shown for hopper type rail cars used to carry bulk commodities or materials. Cylinders provide horizontal motion to rotate an axle on which cam closers are attached thereto. The cam closers operate between a relaxed position (down position) and a raised position (up position). During rotation of the cam closers from the relaxed position to the raised position, the cam closers push hopper doors under the rail car up to a latched position. Individual hopper doors can be closed, or multiple doors can be simultaneously closed, depending on the preference of the operator. The cylinders are protected from falling bulk commodities by an elongated tent frame structure. | 1 |
RELATED APPLICATIONS
This is a division of application Ser. No. 08/367,862 filed Jan. 3, 1995 (U.S. Pat. No. 5,462,970), which is a division of application Ser. No. 08/061,707 filed May 17, 1993 U.S. Pat. No. 5,393,757, which is a continuation-in-part of application Ser. No. 07/870,441 filed Oct. 9, 1991 (abandoned), which is a continuation-in-part of application Ser. No. 07/210,520 filed Jun. 23, 1988 (U.S. Pat. No. 5,091,576), which is a continuation-in-part of application Ser. No. 07/066,227 filed Jun. 25, 1987 (abandoned), which was a continuation-in-part of application Ser. No. 06/936,835 filed Dec. 2, 1986 (abandoned).
This invention was made with United States Government support under Grant NCDDG-CA37606, awarded by the National Cancer Institute. The United States Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
The present invention relates to certain novel anti-diarrheal and gastrointestinal anti-spasmodic agents and methods of treatment and pharmaceutical compositions based thereon.
DESCRIPTION OF THE PRIOR ART
Diarrhea can result from a variety of pathophysiological disorders including bacterial and parasitic infections, disease or debilitation of organs such as liver, adrenal and others. It can also occur as a result of other therapy or diet. In all cases, diarrhea is generally a symptom of organic gastrointestinal disorders and not itself a disorder. Chronic diarrhea is generally due to: (1) hypersecretion of fluid and electrolytes of the stomach, small intestine and colon; (2) inability to absorb certain nutrients (malabsorption); and (3) intestinal hypermotility and rapid transport. These may occur separately or in combination. Certain disorders may have diarrhea as a prominent feature of the disease/syndrome, but the specific etiology is unclear. In this latter group, emotional tension and psychological factors may adversely influence the frequency of the symptoms.
Diarrhea and diarrheal diseases are one of the most frequent causes of morbidity and mortality, especially in less developed countries wherein the number of those killed by such diseases is estimated at about 5 million persons per annum. Particularly dangerous are diarrheal diseases of the newborn and the youngest group of babies (S. Hughes: Drugs, Vol. 26, pp. 80-90 (1983)).
In mechanized or automated large capacity farms, diarrhea and infections of the respiratory tract are frequent, especially with young livestock and the high mortality or growth deceleration thereof have a considerable negative economical effect. Diarrheal diseases of man and animals are caused by a plurality of etiological factors, especially of microbial and viral character. The most prevalent microbes are gram-negative bacteria, Escherichia coli and Vibrio cholerae . However, it is now clear that other bacteria, viruses and parasites (protozoan, amoeba, etc.) also cause severe problems.
Diarrheal diseases are treated by rehydration therapy using preparations composed of various salts (potassium chloride, sodium chloride, sodium hydrogen carbonate) and glucose, whereby quick compensation for the loss of water and ions, as well as for acidosis, occurs. However, the occurrence of diarrheal diseases is not influenced. Other substances of the same kind produce similar results.
Anti-diarrheal compounds are, of course, well known in the medicinal arts and take various forms. In particular, there are a variety of products known which act systemically to provide anti-diarrheal effects when administered in a manner which will enable the drug to be taken into the system at effective therapeutic levels.
In addition, there are anti-cholinergic substances applied together with spasmolytics such as Reasec® (Janssen) which contain diphenyloxylate and atropin. Both human and veterinary medicine use chemotherapeutic agents with anti-bacterial effects, such as sulfonamides, or antibiotics are availed of which are apt to suppress certain infections.
Medicaments are also aimed at the sphere of regulation depending on receptors, especially those localized on the basolateral membrane, further by means of an intracellular mechanism of intervention by the so-called secondary messenger, and by influencing the transport mechanism, especially boundary membranes. The modulation of receptor-dependent regulation mechanisms can be influenced, to some extent, by medicaments of the type alpha, adrenergic agonists such as clonidine (Catapresan®) (E. B. Chang et al, Gastroenterology, Vol. 91, pp. 564-569 (1986)), somato-statin, or encephalin and morphine analogs. For influencing the transport of ions through the membrane, it is also possible to use alpha 2 adrenergic agonists (E. B. Chang et al, Am. J. Physiol., Vol. 1982, p. 242). Reference has also been made to the use of lidamidine, i.e., the medicament having a damping effect on the intestine peristaltics (M. D. Dharmsathphorn: Gastroenterology, Vol. 91, pp. 769-775 (1986)).
Disadvantages of anti-diarrheal medicaments, i.e., those referred to in professional papers rather than those medicaments of this type applied in practice, include their secondary strong effects such as anti-hypertensive effects (clonidine), growth factors (somatostatin), habituation and/or incomplete pre-clinical research (encephalin derivatives). The application of large doses of antibiotics and long administration thereof has not proved optimum in epidemical diarrhea localities. Where the diarrhea inducing agent is cholera toxin, however, there does not exist any efficient protection, except for inoculum which is not sufficiently patent either, and gives short term protection only (3 months) and low efficiency (30-40%).
In recent years, a great deal of attention has been focussed on the polyamines, e.g., spermidine, norspermidine, homospermidine, 1,4-diaminobutane (putrescine) and spermine. These studies have been largely directed at the biological properties of the polyamines probably because of the role they play in proliferative processes. It was shown early on that the polyamine levels in dividing cells, e.g., cancer cells, are much higher than in resting cells. See Janne et al, A. Biochim. Biophys. Acta., Vol. 473, p. 241 (1978); Fillingame et al, Proc. Natl. Acad. Sci. U.S.A., Vol. 72, p. 4042 (1975); Metcalf et al, J. Am. Chem. Soc., Vol. 100, p. 2551 (1978); Flink et al, Nature (London), Vol. 253, p. 62 (1975); and Pegg et al, Polyamine Metabolism and Function, Am. J. Cell. Physiol., Vol. 243, pp. 212-221 (1982).
Several lines of evidence indicate that polyamines, particularly spermidine, are required for cell proliferation: (i) they are found in greater amounts in growing than in non-growing tissues; (ii) prokaryotic and eukaryotic mutants deficient in polyamine biosynthesis are auxotrophic for polyamines; and (iii) inhibitors specific for polyamine biosynthesis also inhibit cell growth. Despite this evidence, the precise biological role of polyamines in cell proliferation is uncertain. It has been suggested that polyamines, by virtue of their charged nature under physiological conditions and their conformational flexibility, might serve to stabilize macromolecules such as nucleic acids by anion neutralization. See Dkystra et al, Science, vol. 149, p. 48 (1965); Russell et al, Polyamines as Biochemical Markers of Normal and Malignant Growth (Raven, New York, 1978); Hirschfield et al, J. Bacteriol., Vol. 101, p. 725 (1970); Hafner et al, J. Biol. Chem., Vol. 254, p. 12419 (1979); Cohn et al, J. Bacteriol., Vol. 134, p. 208 (1978); Pohjatipelto et al, Nature (London), Vol. 293, p. 475 (1981); Mamont et al, Biochem. Biophys. Res. Commun., Vol. 81, p. 58 (1978); Bloomfield et al, Polyamines in Biology and Medicine (D. R. Morris and L. J. Morton, eds., Dekker, New York, 1981), pp. 183-205; Gosule et al, Nature, Vol. 259, p. 333 (1976); Gabbay et al, Ann. N.Y. Acad. Sci., Vol. 171, p. 810 (1970); Suwalsky et al, J. Nol. Biol., Vol. 42, p. 363 (1969); and Liguori et al, J. Mol. Biol., Vol. 24, p. 113 (1968).
However, regardless of the reason for increased polyamine levels, the phenomenon can be and has been exploited in chemotherapy. See Sjoerdsma et al, Butterworths Int. Med. Rev.: Clin. Pharmacol. Thera., Vol. 35, p. 287 (1984); Israel et al, J. Med. Chem., Vol. 16, p. 1 (1973); Morris et al, Polyamines in Biology and Medicine; Dekker, New York, p. 223 (1981); and Wang et al, Biochem. Biophys. Res. Commun., Vol. 94, p. 85 (1980).
It has been previously reported that diethylhomospermine (DEHSPM) inhibited myoelectric activity and transit of the small intestine in rats [J. Gastro. Motil., Vol. 1, p. 53 (1989)]. This inhibition was reversed with co-administration of bethanechol, a cholinergic agonist, but not with other agonists or antagonists [Gastro., Vol. 98, p. A388 (1990)]. However, there is no suggestion or disclosure in the prior art that any of the above-described polyamines have utility as anti-diarrheal or gastrointestinal anti-spasmodic agents.
It is an object of the present invention to provide novel anti-diarrheal and gastrointestinal anti-spasmodic pharmaceutical compositions containing certain polyamine compounds which are not subject to the above-noted disadvantages associated with prior art agents.
SUMMARY OF THE INVENTION
The foregoing and other objects are realized by the present invention, one embodiment of which is an anti-diarrhealn, anti-secretory, nitric oxide agonist, nitric oxide synthase activating or gastrointestinal anti-spasmodic pharmaceutical composition comprising an anti-diarrheal or gastrointestinal anti-spasmodic (hereinafter “GI anti-spasmodic”) effective amount of a compound of the formulae set forth below and a pharmaceutically acceptable carrier therefor.
An additional embodiment of the present invention comprises a method of treating a human or non-human animal in need thereof comprising administering to the animal an anti-diarrheal or GI anti-spasmodic effective amount of a compound of the formulae below.
Suitable polyamines for use in the composition and method of the invention are those described in application Ser. No. 07/210,520 filed Jun. 23, 1988, now U.S. Pat. No. 5,091,576.
The polyamines suitable in the practice of the invention include those having the formula: R 1 —N 1 H—(CH 2 ) 3 —N 2 H—(CH 2 ) 3 —N 3 H—(CH 2 ) 4 —N 4 H—(CH 2 ) 3 —N 5 H—(CH 2 ) 3 —N 6 H—R 6 (II);
or
wherein:
R 1 and R 6 may be the same or different and are H, alkyl or aralkyl having from 1 to 12 carbon atoms;
R 2 -R 5 may be the same or different and are H, R 1 or R 6 ;
R 7 is H, alkyl, aryl or aralkyl having from 1 to 12 carbon atoms;
m is an integer from 3 to 6, inclusive; and
n is an integer from 3 to 6, inclusive; or
(IV) a salt thereof with a pharmaceutically acceptable acid;
and a pharmaceutically acceptable carrier therefor.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is predicated on the discovery that polyamines of the above formulae act to inhibit the potential for the large and small intestines to contract. While not wishing to be bound by any theory as to the mechanism of action of the polyamines as inhibitors of this action of the intestines, it is hypothesized that the polyamines function via a receptor-dependent regulation mechanism whereby the myoelectric activity of the muscle tissue of the colon and small intestine and the secretion of fluid and electrolytes by these organs are modulated. In addition, some of these above effects may be directly or indirectly mediated through the release of nitric oxide or through the activation of nitric oxide synthase.
For each of the utilities mentioned herein, the amount required of active agent, the frequency and mode of its administration will vary with the identity of the agent concerned and with the nature and severity of the condition being treated and is, of course, ultimately at the discretion of the responsible physician or veterinarian. In general, however, a suitable dose of agent will lie in the range of about 0.001 mg to about 500 mg per kilogram of mammal body weight being treated. Administration by the parenteral route (intravenously, intradermally, intraperitoneally, intramuscularly or subcutaneously) is preferred for a period of time of from one to ten days. For chronic problems, the drug is administered as needed.
While it is possible for the agents to be administered as the raw substances, it is preferable, in view of their potency, to present them as a pharmaceutical formulation. The formulations of the present invention, both for veterinary and human use, comprise the agent together with one or more acceptable carriers therefor and optionally other therapeutic ingredients. The carrier(s) must be “acceptable” in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient thereof. Desirably, the formulations should not include oxidizing agents and other substances with which the agents are known to be incompatible. The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. All methods include the step of bringing into association the agent with the carrier which constitutes one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing into association the agent with the carrier(s) and then, if necessary, dividing the product into unit dosages thereof.
Formulations suitable for parenteral administration conveniently comprise sterile aqueous preparations of the agents which are preferably isotonic with the blood of the recipient. Suitable such carrier solutions include phosphate buffered saline, saline, water, lactated ringers or dextrose (5% in water). Such formulations may be conveniently prepared by admixing the agent with water to produce a solution or suspension which is filled into a sterile container and sealed against bacterial contamination. Preferably, sterile materials are used under aseptic manufacturing conditions to avoid the need for terminal sterilization.
Such formulations may optionally contain one or more additional ingredients among which may be mentioned preservatives, such as methyl hydroxybenzoate, chlorocresol, metacresol, phenol and benzalkonium chloride. Such materials are of special value when the formulations are presented in multi-dose containers.
Buffers may also be included to provide a suitable pH value for the formulation and suitable materials include sodium phosphate and acetate. Sodium chloride or glycerin may be used to render a formulation isotonic with the blood. If desired, the formulation may be filled into the containers under an inert atmosphere such as nitrogen or may contain an anti-oxidant and are conveniently presented in unit dose or multi-dose form, for example, in a sealed ampoule.
It will be appreciated that while the agents described herein form acid addition salts and carboxyl acid salts, the biological activity thereof will reside in the agent itself. These salts may be used in human and in veterinary medicine and presented as pharmaceutical formulations in the manner and in the amounts (calculated as the base) described hereinabove, and it is then preferable that the acid moiety be pharmacologically and pharmaceutically acceptable to the recipient. Examples of such suitable acids include (a) mineral acids: hydrochloric, hydrobromic, phosphoric, metaphosphoric, and sulfuric acids; (b) organic acids: tartaric, acetic, citric, malic, lactic, fumaric, benzoic, glycollic, gluconic, gulonic, succinic and arylsulfonic, for example, p-toluenesulfonic acids.
In compounds of the invention, R 1 and R 6 are preferably methyl, ethyl, propyl, benzyl, etc., it being understood that the term “aralkyl” is intended to embrace any aromatic group, the chemical and physical properties of which do not adversely affect the efficacy and safety of the compound for therapeutic applications. Preferred, however, are the hydrocarbyl aralkyl groups, i.e., comprised only of C and H atoms.
R 2 -R 5 preferably are H, methyl, ethyl, propyl or benzyl.
Compounds of the above formulae are synthesized according to the methods described in application Ser. No. 07/210,520 filed Jun. 23, 1988, now U.S. Pat. No. 5,091,576, and Ser. No. 07/870,441 filed Oct. 9, 1991, the entire contents and disclosures of both of which are incorporated herein by reference.
Although, as noted above, it has been reported that diethylhomospermine (DEHSPM) inhibits gastrointestinal motility in rats, it has been determined that this inhibition is extremely dependent on structural motifs within the molecule. Preliminary receptor binding experiments suggest that DEHSPM is not a classic anti-cholinergic or anti-adrenergic.
The invention is illustrated by the following non-limiting examples.
EXAMPLE 1
This study represents an attempt to elucidate a possible mechanism(s) for the above-noted observed inhibition of gastrointestinal motility in rats. The phasic and sustained contractions of guinea pig taenia coli were determined in a perfused organ bath apparatus. DEHSPM (0.1 mM, 0.5 mM and 1.0 mM) progressively inhibited spontaneous phasic contractions by a TTX-insensitive mechanism. TTX (1.0-20.0 μM) blocked field stimulation-induced contractions without altering the DEHSPM attenuation of phasic contractions:
Treatment
Phasic Contract/20 min.
Amplitude/20 min.
Baseline
5.8 ± 0.4
4.8 ± 0.3
DEHSPM (1.0 mM)
2.3 ± 0.5***
2.2 ± 0.4***
***p < 0.0001 compared to baseline. Data expressed as mean ± SEM.
In an attempt to support the above bethanechol experiments, increasing cumulative concentrations of carbachol (1.0 nM to 1.0 μM half-log changes) were used alone and following DEHSPM (1.0 mM). Only the highest concentration (1.0 μM) of carbachol was able to overcome the inhibitory effects of DEHSPM. Interestingly, the majority of the tissues tested (>80%) were of the phasic contractile type. In order to consistently test the sustained contractions, 20 mM KCl was used to induce a sustained contraction. Similar to the phasic tissues, DEHSPM (1.0 mM) significantly inhibited the KCl-induced contraction. Results are expressed as the extent of relaxation (%) and as compared to nitroprusside (1.0 mM), a classic relaxation agent:
Treatment
% Relaxation
% Nipride Relaxation
DEHSPM (1.0 mM)
81 ± 11
240
DEHSPM (0.5 mM)
33 ± 4
129
DEHSPM (0.1 mM)
5 ± 2
16
Both the nitric oxide synthase inhibitor, L-NAME (20 mM), and methylene blue (10 μM) partially blocked the inhibition caused by DEHSPM. Hemoglobin-containing compounds partially block DEHSPM-induced inhibition of phasic contractions and relaxation of KCl-induced contractions. It can be deduced, therefore, from the above results that the profound inhibition caused by DEHSPM in isolated GI tissues is due, in part, to a nitric oxide mechanism. DEHSPM apparently causes relaxation either through a direct myogenic interaction or through an Na-independent neural pathway.
EXAMPLE 2
To test the hypothesis that DEHSPM would cause alterations of myoelectric activity and transit of the small intestine similar to those noted with the use of isoproterchol (ISO), myoelectric activity was monitored in rats during fasting by four in-dwelling electrodes. Intestinal transit was measured by the movement of radiochromium, expressed as the geometric center. Intestinal myoelectric activity and transit were determined after a single s.c. injection of saline or 5 mg/kg DEHSPM. In addition, myo-electric activity was monitored after chronic administration of 5 mg/kg bid for 6 days. The interval between activity fronts (AF) of the migrating myoelectric complex (MMC), propagation velocity of the AF and the duration of spike inhibition (min.) after each injection are reported below:
AF Propagation
Inhi-
Geo.
AF Interval
Velocity
bition
Ctr.
Baseline
10.8 ± 1.0
3.0 ± 0.5
—
4.0 ± 0.5
Single
Day 1
22.6 ± 1.6*
1.3 ± 0.1*
44.5 ± 3.2*
1.3 ± 0.2*
Day 4
14.7 ± 2.4
1.5 ± 0.1*
—
—
Chronic Day 5
40.3 ± 8.9*
1.8 ± 0.3
—
—
Mean ± SEM in minutes.
*p 0.05 propagation velocity = cm/min.
In summary, therefore, it can be stated, based on the above evidence, that (1) DEHSPM causes significant inhibition of small intestinal myoelectric activity; (2) DEHSPM significantly delays transit of small intestine; and (3) chronic administration of DEHSPM induces profound alterations of intestinal motility.
These findings with DEHSPM are similar to those reported after administration of ISO, but DEHSPM-induced alterations have a much longer duration. It is hypothesized that polyamines may interact non-covalently with specific biochemical macromolecules or a second messenger system responsible for the maintenance of intestinal motility. Furthermore, the gastrointestinal toxicity observed with DEHSPM appears to be related to alterations of intestinal motility.
EXAMPLE 3
Further studies were conducted to determine the effect of DEHSPM on gastric emptying and selected pharmacologic agents were used to determine the mechanism of action. A radiochromium method was used to measure the % gastric emptying (GE) and intestinal transit expressed as geometric center (GC). Percent GE, % reversal in GE from DEHSPM treatment and GC were determined after a single dose of DEHSPM and the respective pharmacologic agent with the following results:
Treatment (mg/kg Route)
% GE
% Reversal
GC
Saline Control
82.5 ± 3.0
100.0
5.1 ± 0.3
DEHSPM (5 sc) + Saline
14.3 ± 4.2
—
1.5 ± 0.2
Metoclopramide (5 ip)
27.4 ± 2.3
19.6*
1.6 ± 0.1
Verapamil (5 ip)
45.4 ± 2.8
45.2***
2.3 ± 0.1**
Propranolol (5 sc)
44.7 ± 5.3
44.2**
1.9 ± 0.2
Yohimbine (1 sc)
31.3 ± 5.7
24.4
2.1 ± 0.2
Naloxone (1 sc)
34.4 ± 6.5
29.2
2.2 ± 0.2
Bethanechol
(0.05 ip)
44.8 ± 8.2
44.3**
2.2 ± 0.1
(0.5 ip)
85.2 ± 2.8
103.0***
3.6 ± 0.2***
(10.0 ip)
94.9 ± 0.9
117.2***
6.4 ± 0.3***
Mean ± SEM. p values: * < 0.05, ** < 0.02, *** < 0.0002
In summary, (1) DEHSPM significantly delayed GE and small intestinal transit; (2) DEHSPM's inhibition of GE was only partially but significantly reversed by dopaminergic, calcium channel, and β-adrenergic antagonists. In contrast, bethanechol completely reversed DEHSPM's effect. (3) DEHSPM's inhibition of intestinal transit was improved significantly by a calcium channel antagonist and a cholinergic agonist.
These data suggest that calcium mobilization and the β-adrenergic system are intimately involved in DEHSPM's effect on motility. This is probably not an atropine-like effect because atropine does not inhibit motility in rats. It can be postulated that bethanechol may provide an important adjunct to chemotherapeutic regimes containing analogs of the polyamine pathway.
EXAMPLE 4
The activity of DEHSPM as a potent anti-diarrheal agent was tested in a castor oil-induced diarrhea model in rats. Fastedrats were injected s.c. with saline or DEHSPH at 0.2, 1.0 or 5.0 mg/kg and had orogastric gavage of 2 ml of castor oil. Time of first diarrheal stool (min.) and weight (wt.) loss at 2, 4 and 6 hours were measured. The results are expressed below as mean ±SEM.
2 Hour
4 Hour
6 Hour
1st Stool
Wt. Loss
Wt. Loss
Wt. Loss
Saline
104 ± 30
4.1 ± 0.9
7.2 ± 1.2
9.1 ± 1.1
0.2 mg/kg
261 ± 40*
1.6 ± 0.4*
3.8 ± 0.6*
5.2 ± 0.7*
1.0 mg/kg
>360**
0.7 ± 0.3**
2.0 ± 0.3**
2.5 ± 0.4**
5.0 mg/kg
>360**
1.1 ± 0.3**
1.9 ± 0.3**
2.6 ± 0.4**
* p < 0.02 and ** p < 0.001 compared to saline + castor oil
Interestingly, L-NAME, a nitric oxide synthase inhibitor, is reported to prevent diarrhea in this animal model and it can be reversed with L-arginine. DEHSPM may interact with oxygen radicals because it has potent cyto-protective effects against alcohol-induced gastritis. Therefore, it was hypothesized that L-arginine may reverse DEHSPM's anti-diarrheal effect. L-arginine, 600 mg/kg i.p., failed to alter DEHSPM's beneficial effects in this model. In summary, then, DEHSPM is a potent anti-diarrheal agent that profoundly inhibits motility. The possibility cannot be excluded that DEHSPM may also have anti-secretory activity because the lowest dose that was effective in this diarrheal model has only limited anti-transit effects.
EXAMPLE 5
The mechanism by which DEHSPM inhibits diarrhea was further studied by investigating the effects of the compound on cholera-induced secretion in the ligated intestinal loop model in rats. In this model, the rats were anesthetized and isolated intestinal loops Were separated and 10 μg of cholera toxin was injected along with a small amount of saline. DEHSPM caused a significant reduction in the amount of accumulated fluid in jejunal segments and a trend to decrease fluid acceleration in the ileum. This effect was dose-related and occurred at 0.2 mg/kg s.c., but its enhanced absorption was more marked at the 1 and 5 mg/kg dose. The results from those doses compared favorably to the response observed with large doses of clonidine, in α 2 -adrenergic agonist used in reference compound. | Anti-diarrheal, anti-secretory, nitric oxide agonist, nitric oxide synthase activating or gastrointestinal anti-spasmodic compounds of the formula: R 1 —N 1 H—(CH 2 ) 3 —N 2 H—(C 2 ) 3 —N 3 H—(CH 2 ) 4 —N 4 H—(CH 2 ) 3 —N 5 H—(CH 2 ) 3 —N 6 H—R 6 (II);
or
wherein:
R 1 and R 6 may be the same or different and are H, alkyl or aralkyl having from 1 to 12 carbon atoms;
R 2 -R 5 may be the same or different and are H, R 1 or R 6 ;
R 7 is H, alkyl, aryl or aralkyl having from 1 to 12 carbon atoms;
m is an integer from 3 to 6, inclusive; and
n is an integer from 3 to 6, inclusive; or
(IV) a salt thereof with a pharmaceutically acceptable acid;
and a pharmaceutically acceptable carrier therefor. Methods of treatment utilizing the composition are also disclosed. | 8 |
TECHNICAL FIELD
This invention relates to upholstery fabrics intended in use to cover at least part of the surface of a three-dimensional structure and in particular but not exclusively to upholstery for seats, especially vehicle seats.
BACKGROUND OF THE INVENTION
Three-dimensional fabric covers for seats have in the past been produced from woven or knitted fabric which has been cut into shaped panels which are then sewn together.
More recently it has been found possible to continuously knit one-piece piece upholstery fabric, which removes the need for cutting and sewing, and has the desired shape to serve as covers for the back and base cushions of motor vehicle seats; see, for example, U.S. Pat. Nos. 5,308,141 and 5,326,150.
It is necessary to provide anchorage devices at the edges of the covers to enable the covers to be secured to a support and held tautly over their respective cushions. The anchorage devices typically take the form of tubular portions which may be formed by sewing or by integrally knitting said portions. The tubular portions accommodate rods which are recessed into the cushions and secured under the support. If the base and back cushions comprise bolsters, it may also be necessary to provide anchorage devices on the undersurface of the cover in order to conform the cover to the shape of the upper surface of the cushion. The anchorage devices are typically open ended tubular flaps which are formed by sewing or integral knitting as shown in U.S. Pat. No. 5,326,150. It is difficult to hold the central panel of a seat back cover down against the foam cushion. It is not usually possible to utilize metal rods and hog rings in this region. Typically the cover is held in place by adhesives, Velcro™, or more usually by passing elastomeric cord through the flaps and anchoring each end of the tensioned cord to a suitable point on the seat support. These anchorage points have to be hidden from sight.
The elastomeric cord, tubular flap formation, threading of the cord and location of the anchorage means are costly.
SUMMARY OF THE INVENTION
According to the invention, there is provided a fabric cover knitted from yarn in a generally double jersey construction for covering a three-dimensional core, the fabric cover having an exposed front layer with a rear layer adjacent the core, the rear layer of the cover having formed integrally therewith a coursewise extending single jersey tubular portion which is less extensible than the surrounding fabric, with single jersey tie-down loops formed at each end of the tubular portion.
The loops provide anchorage points for pulling the non-extensible coursewise linear area down onto the core and preventing bridging. The formation of the tubular portion and tie-down loops is substantially invisible on the front face.
Preferably, the tubular portion comprises six to 20 courses, and preferably 16 courses of single jersey knitting of a cross float construction, and the tie-down loops comprise 25 to 60 courses of cross float single jersey fabric, and preferably 38 to 40 courses.
Preferably, the single jersey tubular portion and the single jersey tie down loops are knitted in a cross float construction in which in each row of knitting the yarn is knitted for a single loop at intervals which do not exceed four wales, and more preferably every other wale.
The tubular portion and tie down loops may be knitted from a high modulus yarn, such as HYTREL or LYCRA, preferably a 1000 denier monofilament.
Also according to the invention there is provided a method of knitting a fabric cover of a generally double jersey construction on a flat "V" bed knitting machine having a front bed for knitting the front layer of the fabric and a rear bed for knitting the rear layer of the fabric, the method including knitting a double jersey fabric on both needle beds, and at a predetermined course of knitting the front needle bed is held up, and knitting continues on selected needles on the rear needle bed up to a second course. Thereafter, knitting continues on a group of needles at each end of the selected needles up to a third predetermined course, then knitting recommences on all selected needles up to a fourth predetermined course. Thereafter, knitting recommences on all needles on both needle beds to form fabric having on the rear layer a pair of tie-down loops having a single jersey tubular portion extending coursewise therebetween.
Preferably, the fabric is knitted on a machine having seven to 14 needles per inch, and preferably 12 needles per inch. The double jersey fabric is knitted from at least one yarn which is preferably air textured polyester yarn having a decitex in the range of 500-800 decitex, or could be chenille yarn of the type disclosed in U.S. Pat. No. 5,428,969 which has a ground yarn with a count in the range 550-900 decitex and a chenille yarn having a decitex in the range of 1700-5000.
Yet another aspect of the invention provides a method of securing a double jersey knitted fabric cover to a core by integrally knitting a pair of tie-down loops in the rear layer of the fabric, the tie-down loops being spaced apart in a coursewise direction and being interconnected by a coursewise extending tubular portion which is less extensible that the surrounding fabric, and wherein the loops are utilized for putting the cover under tension to pull the cover against a respective core.
The cover is preferably for a motor vehicle seat cushion or back.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described by way of example and with reference to the accompanying drawings in which:
FIG. 1 is a seat back in accordance with the present invention,
FIG. 2 is a knitting pattern for a fabric piece according to the present invention,
FIG. 3 is an isometric view of the rear face of a fabric piece according to the invention,
FIG. 4 is a view of the fabric piece of FIG. 3 in tension when in use,
FIG. 5 is a knitting diagram showing a first stitch structure for knitting the less extensible courses, and
FIG. 6 is a second stitch structure for knitting the less extensible courses.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, this shows an isometric view of a seat back 11 having a foam core 12 covered by a double jersey knitted fabric cover 13. The foam core 12 is typically mounted on a metal frame to which the cover 13 is secured to hold the cover tautly against the surface of the core.
The cover 13 is continuously knitted in three dimensions on a flat "V" bed knitting machine having independently operable needle beds. The seat back 11 may comprise a front F having side bolsters 14, 15 and top and bottom bolsters 16, 17. The cover 13 when fitted over the core 12 has a central front panel 18 which, as a consequence of the presence of bolsters 14-17, can bridge the core 12. The cover 13 therefore requires pulling down and holding against the surface of the foam core. This also prevents shuffling of the cover on the core. The cover is held in tension along at least two vertical lines L1 and L2 lying one on each side of the central panel 18. The vertical lines L1 and L2 correspond with the coursewise direction of knitting for the double jersey fabric cover 13.
With reference to FIGS. 3 and 4, there is shown in rear view a portion of the cover 13 having on its rear face 21 a coursewise extending tubular portion 22 which is less extensible than the surrounding double jersey fabric. The tubular portion 22 has a larger tie down loop 23, 24 formed at each end thereof. The loops 23, 24 and tubular portion are formed contiguously with each other and may have the same knitted construction. The loops 23, 24 are readily deformable into the condition shown in FIG. 4 to transmit a tension load to the fabric which is less extensible between the loops.
With reference now to FIG. 2, there is shown a knitting pattern 30 for a portion of a cover 13 to illustrate how the less extensible tube 22 and tie-down loops 23, 24 are formed.
Knitting of fabric cover 13 which is of a generally double jersey construction takes place on a flat "V" bed knitting machine having a front bed for knitting the front layer of the fabric and a rear bed for knitting the rear layer of the fabric. The needle beds are shown schematically in FIGS. 5 and 6 in which each dot represents a needle, and the upper row F of dots represents the front needle bed and the lower row R of dots represents the rear needle bed.
Knitting commences at the set up course A in the direction of arrow Z on all needles between the needle lines S and X. A double jersey structure fabric is knitted on both needle beds up to a first predetermined course B. Thereafter, knitting on the front needle bed is held up, and knitting continues for between six to 12 courses, preferably eight courses, on selected needles T-W on the rear needle bed up to a second predetermined course C. The width of the needle bed T-W could be up to 300 needles.
Thereafter knitting continues, for up to between a further 20 to 50 more courses, and preferably 38 courses on two groups of needles T-U and V-W located one group at each end of the selected needles T-W up to a third predetermined course D. The groups of needles T-U and V-W may comprise between six and 25 needles, preferably about 14 needles.
Then knitting recommences on all selected needles T-W for the same number of courses as between courses B and C, up to a fourth predetermined course E. Knitting then recommences on all needles on both needle beds F and R to form the fabric piece.
The tubular portion 22 and loops 23, 24 formed on the rear layer are formed by a single jersey knitting on the needles T-W. The tubular portion 22 is formed by the fabric portions 30 and 31 between the course lines B-C and D-E, respectively, and extends walewise for a total of 16 courses. The tie-down loops 23, 24 preferably extend for a further 38 courses between course lines C-D. Preferably the loops 23, 24 and tubular portion both have the same knit construction.
The preferred construction is to knit the single jersey tubular portion and tie down loops from a cross float type stitch.
Now with reference to FIG. 5, there are shown two rows 1 and 2 making a repeat unit. The front bed F is held up with all needles rendered inactive, and yarn 40 is knitted on every other needle on the rear bed R. The yarn 40 floats across inactive needles in the rear bed. This is called a 1×1 cross float single jersey.
A second embodiment is shown on FIG. 6 which illustrates four rows 1-4 making a repeat unit. Again, the front needle bed F is rendered inactive, and the yarn 40 is knitted on every fourth needle with the yarn floating between the knitted needles. This is called a 3×1 cross float single jersey.
The second structure is less extensible than the 1×1 construction.
The yarn 40 is preferably one of the ground yarns of the double jersey fabric, but could be a high modulus yarn of the type discussed earlier.
In another embodiment of the invention, the tube 22 and tie-down 25 loops 23, 24 could be knitted on all needles on the rear bed R in single jersey construction from a high modulus yarn. | A three-dimensional continuously knitted fabric cover knitted from yarn in a generally double jersey construction for covering a three-dimensional core, the fabric cover having an exposed front layer with a rear layer adjacent the core having formed integrally therewith a securing means formed as a coursewise extending single jersey tubular portion which is less extensible than the surrounding fabric, with single jersey tie-down loops formed at each end of the tubular portion. | 3 |
FIELD OF THE INVENTION
The invention relates to a random-number generator.
RELATED TECHNOLOGY
The generation of random numbers is more important today than ever before. The quality of random numbers plays a considerable, and possibly even a key role, not only in electronic check cards, in smart master-key systems, but also in the on-line accessing of databases. Apart from the constantly increasing quantity of random numbers required, it is also necessary to ensure that externally accessible correlations or possibilities of decryption are reduced to a minimum.
To date, essentially two different classes of method have been used for generating random numbers:
1. Algorithmic Methods
With these methods, a short initial sequence (“seed”) is used to generate a considerably longer pseudo-random sequence with the aid of mathematical operations which can be executed in software or hardware. The random-number generators based on this method differ very greatly in quality and frequently do not satisfy cryptographic requirements. However, they are capable of supplying reproducible random numbers, which may be extremely useful for simulation purposes.
2. Physical Methods
With these methods, use is made of the statistical nature of certain physical processes. Generally, these processes can be further subdivided into:
Statistical processes which, although they obey deterministic equations of motion, are not predictable owing to their high degree of complexity and lack of knowledge of the initial state.
Fundamentally random processes (elementary processes) of the kind predicted by quantum mechanics. As science stands at present, these processes cannot be reduced to hypothetical deterministic mechanisms at subquantum level and are therefore basically random in nature.
Bit strings that are generated by physical processes, particularly by fundamentally random physical processes, more closely approach the concept of a random sequence than do algorithmically generated sequences. Consequently, it was recognized at an early date that, for example, radioactive decay measurements are very well suited for generating random sequences; see MARTIN GUDE: “A quasi-ideal uniform-distribution generator based on random physical phenomena”, dissertation at RWTH Aachen (1987). A disadvantage in this regard, however, is the potentially detrimental effect of radioactive radiation on humans and on sensitive electronic equipment.
Other random-number generators use physical noise sources, such as semiconductor diodes, to generate random bit sequences; see, for example, MANFRED RICHTER: “A noise generator for obtaining quasi-ideal random numbers for stochastic simulation”, dissertation at RWTH Aachen (1992). With these methods, however, it is often difficult to set the decision-making threshold (between bit value 0 and bit value 1) precisely and invariably with respect to time. Furthermore, for cryptographic applications it is very important to exclude external influences on the random mechanism; this is not easy to achieve especially when electronic phenomena are used.
The random process of the path selection of individual photons at the beam splitter has already been proposed for generating random sequences: see J. G. RARITY et al.: “Quantum random-number generation and key sharing”, J. Mod. Opt. 41, p. 2435 (1994), which is hereby incorporated by reference herein. However, the random nature of the output sequence can be interfered with by spurious external pulses, as well as by incorrect counting of the photon detectors.
Individual photons do not divide at the optical beam splitter, but randomly and unpredictably take one of the two possible paths. Photon detectors in the outputs of the beam splitter therefore generate a random sequence, whose quality is based on the fundamental natural laws of quantum mechanics. However, a disadvantage of the method lies in the fact that spurious pulses of the detectors caused by external influences, for example by cosmic radiation, and not attributable to the random-number-generating mechanism at the beam splitter are also included in the random sequence. In principle, it would be possible for someone to selectively falsify the random sequence by subjecting the set-up to electromagnetic rays or particles.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a random-number generator which is capable of obviating or reducing the above-described disadvantages, which is not susceptible to external interference, and which supplies random numbers of high quality.
The present invention provides a random-number generator for generating a random number, the random-number generator comprising a particle source capable of emitting at least a first and a second particle more or less simultaneously; a random-number-generating element acting on particles emitted by the particle source; and a detection apparatus for associating a numerical value with a detection of a particle leaving the random-number-generating element, the first particle being capable of activating the detection apparatus so as to detect the second particle and associate a numerical value with the second particle, the second particle being influenced by the random-number-generating element.
Since the particle source according to the present invention is capable of emitting at least two particles more or less simultaneously, with one particle activating the detection apparatus, it is thereby possible for undesired background influences to be virtually entirely prevented. Since the time after activation/triggering of the detection apparatus by the first particle may be so short that essentially only the second particle to have passed through the random-number-generating element is used for generating the binary number (or if the detection apparatus is switched to the deactivated state after detection of the second particle), incorrect measurements are possible only during the very short activated/triggered state or as a result of incorrect triggering. Even in these cases, however, there is an extremely high probability that no errors will occur with the preferred embodiment according to the present invention using an optical beam splitter, because single incorrect triggering would not result in the detection of a second particle or, otherwise with correct triggering in both branches of the beam splitter, a signal would be obtained which can easily be corrected by electronic means.
It is especially advantageous if the particle source includes a photon-pair source for simultaneously generating two photons with correlated polarization, energy and spatial emission distribution, because this makes it possible, due to the already known propagation path, to substantially block out any still existing background radiation using shutters, by the known polarization technique using a polarizer and by a spectral filter.
The operation of the random-number-generating element is further improved if its outputs are associated with two receivers detecting single photons, because the clear proof of a single photon is then able to rule out any remaining uncertainty about the detected photon.
Electronically, the concept of the present invention can be captured in the detection apparatus using combined coincidence/anticoincidence electronics.
Any remaining errors of a beam splitter or of its adjustment, as often occur, can be further suppressed if the random-number-generating element contains a polarizing beam splitter and preferably an upstream λ/2 retardation plate for adjusting the overall splitting ratio.
With an optimally adjusted arrangement of beam splitter and λ/2 retardation plate, future detrimental influences in a mechanical respect can be alleviated in that at least those two assemblies and preferably the associated detectors are jointly held in positions aligned with respect to each other.
In a cost-effective embodiment, the random-number-generating element may comprise a non-polarizing beam splitter, preferably a vacuum-evaporation-coated (metallized) plate and/or a dielectric layer. Also, with this embodiment, it is possible to achieve optimal results if adjustable masks and/or tunable spectral filters are placed in the outputs of the beam splitter in order to balance the optical path and the detection electronics.
BRIEF DESCRIPTION OF THE DRAWINGS
Hereinbelow, the present invention is further elucidated on the basis of preferred embodiments with reference to the drawings, in which:
FIG. 1 shows the basic construction of a random-number-generating apparatus according to the invention;
FIG. 2 shows a first embodiment according to the present invention of a photon-pair source including a laser;
FIG. 3 shows a second embodiment according to the present invention of photon-pair source including a laser; and
FIG. 4 shows a random-number-generating element, with associated detectors, according to the present invention.
DETAILED DESCRIPTION
In the following, the present invention is described in its basic features with reference to the schematic representation in FIG. 1 .
The device according to the present invention, identified in its entirety by reference character 1 , comprises a laser as photon source 3 , a random-number-generating element 2 and coincidence and symmetrizing electronics 4 , which can be activated or triggered by trigger lines 5 and which then receive the signal of the detector outputs 6 .
Referring additionally to FIG. 2, the present invention employs a photon source in which two photons at a time are generated simultaneously in a non-linear optical medium, preferably a crystal 7 . Examples of suitable optical, non-linear crystals are BaB 2 O 4 , KNbO 3 or LiNbO 3 , which can be pumped with the laser 3 such that pairs of correlated photons of double wavelength polarized orthogonally with respect to each other are generated. Physically, this effect is also known as type 2 parametric fluorescence.
The laser 3 may be, for example, an He—Cd laser used at an operating wavelength of 442 nm, which produces photons in the infrared range at 884 nm. A blue filter 8 , acting as spectral filter, is used to block off the plasma light emission of the laser 3 in front of the crystal, and a spectral filter or prism (not shown in the figures) behind the crystal serves to keep the pumping light of the laser 3 away from the further optical path. Each photon pair is spatially divided, one photon striking a beam splitter 9 (best seen in FIG. 4) acting as random-number-generating element, while the other photon is detected directly by the trigger detector 10 .
In a detection apparatus (not shown in the figures), which also contains the coincidence and symmetrizing electronics 4 , only one of the detectors 11 , 12 is read out when the trigger detector 10 supplies a signal simultaneously or after a timed interval.
The detectors 10 , 11 and 12 may be single-photon detectors, for example Si avalanche photodiodes of the kind supplied by EG&G as type C30902, and are in such a case operated cooled by a Peltier cooler preferably at −30° C. An achromatic lens (not shown in the figures) can focus the light beam on the detector and increase the received intensity.
The herein proposed method for the generation of random bit strings employs a fundamental random phenomenon, namely the stochastic division of a stream of single-photon states at the 50:50 beam splitter with downstream single-quantum detection.
The correlation of the counting events of the detectors 11 and 12 of the beam splitter 9 with the signal of the trigger detector 10 improves the random sequence and protects against external interference in the optical path.
According to the present invention, at least two different optical set-ups can be used: the colinear set-up shown in FIG. 2 and the non-colinear set-up shown in FIG. 3, in which the optical paths are at an angle with respect to each other.
In the non-colinear set-up in FIG. 3, the photons are separated already as they are produced in the non-linear crystal 7 in that they propagate in different directions. The two photons of a pair are then already spatially separated and, moreover, their directions of propagation do not coincide with that of the laser. Consequently, it is possible, in comparison with the colinear set-up in FIG. 2, to economize on some of the optical components, particularly the polarizing beam splitter 13 , and the optical losses are correspondingly smaller.
In the set-up in FIG. 3, the photons of a pair do not need to have different directions of polarization and, consequently, it is possible to use type 1 parametric fluorescence, which provides additional flexibility in the optimization of the photon rate since the efficiencies of the type 1 and type 2 processes may differ depending on the sort of crystal used.
The construction of the random-number-generating element 2 is shown in greater detail in FIG. 4 . In a first embodiment according to the invention, the random number-generating element comprises a polarizing 50:50 beam splitter 9 with single-photon detectors 11 , 12 in the outputs thereof and with an optional computer-controlled rotatable λ/2 retardation plate in the input. Through the rotation of said λ/2 plate it is possible for the overall splitting ratio, which, because of the component tolerances in the detectors, would generally differ from 50:50, to be set to better than 0.1% deviation from the ideal value.
The input end of the beam-splitter cube 9 is covered by a pinhole diaphragm except for an opening of 2 mm diameter. Furthermore, the unused input of the beam splitter is covered, and the optical paths to the detectors 11 , 12 are optically sealed against background light.
Instead of the polarizing beam splitter 9 , it is possible in an alternative embodiment according to the present invention, to also employ a non-polarizing beam splitter configured, for example, from a vacuum-evaporation-coated plane-parallel or wedge-shaped plate. The said vacuum-evaporation coating may be metallic or dielectric. Any deviations from the 50:50 ratio in the optical set-up or the electronics can be compensated downstream from the beam splitter by masks or spectral filters.
A detection apparatus, which may be connected to a PC and which may supply said PC with binary data or data in any other form, comprises the coincidence and symmetrizing electronics 4 , which is supplied with the output signals of the detectors 11 and 12 as well as of the trigger detector 10 . In the simplest case, an AND gate with a time delay in one of the inputs is used for this purpose. The output signals of the two coincidence units generate provisional bit values “1” and “0”.
In order to further restrict the influence of undesired light and detector dark counting rates, the output signals of the coincidence units are used to generate, by means of an EXOR gate, an “event” signal which is only “HIGH” when there is a coincidence between the trigger detector 10 and precisely one of the two output detectors 11 , 12 .
In order to generate a completely uniform “0-1” sequence, the output signal is additionally symmetrized using a hardware version of the “von Neumann algorithm”; see, for example, J. von Neumann “Various Techniques Used in Connection with Random Digits”, Appl. Math. Ser., 12, pages 36-38 (1951). With this algorithm, the original sequence is first divided into non-overlapping pairs of consecutive bits and, from those pairs, the output sequence is then generated according to the following rule:
Bit 1
Bit 2
Output bit
1
1
—
1
0
1
0
1
0
0
0
—
Although this method has the disadvantage of an at least 75% reduction in the maximum achievable bit rate, it guarantees a precise 50:50 distribution of the “0”s and “1”s without including undesired correlations, which is difficult to accomplish with other methods that have lower bit rate losses.
The values thus obtained are stored intermediately in a buffer memory and are then transferred to a control computer or PC.
In order to maintain an adjustment, once made, stable, the device according to the present invention and its optical and optoelectronic elements may be built on a separate carrier, such as a two-dimensional optical bench or a mechanically worked block of metal or ceramics. In addition, it lies within the scope of the present invention, once miniature-sized lasers with suitable spectra are available, to implement the random-number generator in an integrated-optoelectronic form. | A random-check generator for generating a random number, which is preferably represented in binary form, having a particle source, a random-check generating element which acts on particles emitted by the particle source, and a detection system which allocates a numerical value, preferably in binary form, to the detection of a particle emerging from the random-check generating element. The random-check generator is not susceptible to external interference and delivers high-quality random numbers. To that end, the particle source can emit at least two particles substantially simultaneously, and one particle can activate the detection system in order to detect a further particle influenced by the random-check generating element and allocate a numerical value thereto. | 6 |
REFERENCE DATA
[0001] This patent application claims priority from European Patent Application EP 03101769.2, filed on Jun. 17, 2003, which is hereby incorporated by reference.
FIELD OF THE INVENTIONS
[0002] The present invention deals with an implantable device, comprising a removable part, for retrievably securing the device inside a body lumen, and a sensor, for measuring, logging and/or transmitting relevant body parameters.
[0003] Implantable devices have long been applied, in particular in conjunction with balloon angioplasty, to restore proper flow in constricted blood vessels. In this application the blood vessel is expanded with an inflatable balloon, guided into the desired section of the vessel by means of a catheter. The intraluminal or intravascular device or stent is then positioned inside the vessel to ensure that it maintains the enlarged diameter once the expanding balloon is removed.
[0004] On the other hand it is known to use miniaturized devices for performing diagnostic or research measurement inside the body of a human or an animal. Such devices are in general inserted inside a blood vessel or another body lumen by a suitable catheter. This procedure, even if it is only moderately invasive, must be performed in a medical establishment and does not allow prosecuting the measurement for an extended period of time or during patient's normal activities.
[0005] Moreover the known stenting devices are in general suitable for definitive implantation only. While safe and reliable procedures to position a stent into a body lumen are well established, this is not generally true for recovering or repositioning an already implanted device. Once a stent is deployed its emplacement is considered definitive and recovering or replacing it would often require invasive surgery.
BRIEF SUMMARY OF THE INVENTION
[0006] An aim of the present invention is to provide a practical and safe device for performing accurate inner measurements for diagnostic, research or therapy, without interfering with patient's normal activities and in a minimally invasive way.
[0007] Another object of the present invention is to provide a replaceable intraluminal or intravascular device, which can safely and easily be recovered from its position inside the body, or moved to a different position, without the necessity of invasive techniques.
[0008] These objects are attained by the devices and method of the independent claims in the corresponding categories, while the remaining claims deal with preferred and alternatives embodiment and examples. In particular, said objects are attained by an implantable intraluminal or intravascular device, i.e. for placement in a body lumen, preferably in a blood vessel, comprising:
[0009] an expandable section having a variable dimension, said variable dimension allowing a compressed value D c for delivery to said body lumen and an expanded value D e , larger than said compressed value D c , for implantation in said body lumen;
[0010] a link section at one end of said device, comprising a grip, for joining said device to a catheter, and for applying an axial force on said device;
[0011] at least one sensor permanently joined to said device;
[0012] wherein said device is arranged for reacting to an axial pulling force to said grip, by assuming said compressed value of said variable dimension, for retrieval or repositioning of said implantable device;
[0000] and by an apparatus for positioning an implantable device according to claim 1 , comprising:
[0013] a flexible catheter, inserted into a flexible sleeve;
[0014] a grasp section, fixed to the tip of said catheter, for cooperating with said link section of said implantable device, said clasp section comprising at least two opposed flexible fingers;
[0015] said flexible sleeve interacting with said flexible fingers for opening and closing them on said link section, and interacting with said expandable section for reducing said variable dimension of said implantable device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be better comprised from the study of the following description and claims and with reference to the appended figures wherein:
[0017] FIG. 1 shows an implantable device according to the invention, connected to a delivery/recovery apparatus according to the invention;
[0018] FIGS. 2 a to 2 d represent a sequence of actions describing the use of the device and the apparatus of FIG. 1 .
[0019] FIG. 3 represent an alternative embodiment of the implantable device according to the invention, comprising a flexible tether.
[0020] FIGS. 4 a and 4 b show another embodiment of the invention wherein the implantable device comprises a tubular mesh;
[0021] FIGS. 5 and 6 illustrate two different fashions of realizing the connexion between the implantable device and the positioning apparatus of the invention;
[0022] FIGS. 7, 8 , 9 , 10 and 11 shows other embodiments of the implantable device according to the invention;
[0023] FIG. 12 shows an application of the device of the invention in conjunction with a vascular stent.
[0024] FIG. 13 shows an implantable device according to the invention and comprising a vascular filter.
DETAILED DESCRIPTION OF THE INVENTION
[0025] According to a first embodiment of the present invention, the implantable device 2 comprises a core 10 , of elongated shape, on which are disposed at least a plurality of elastic struts 6 which can assume all the positions between the fully released configuration visible in FIG. 1 , in which the struts 6 extend radially from the body 10 , and a compressed configuration, in which the struts are almost in full contact with the core 10 .
[0026] The transversal diameter of the device 2 is therefore variable according to the configuration of the flexible struts 6 . In their fully released position the struts 6 define the maximum expanded diameter D e of the device, while the compressed diameter D c is obtained when the struts 6 are in full contact with the core 10 .
[0027] In this particular example of the invention the struts 6 are in number of 8 , and disposed, as shown on FIG. 1 , in two levels, each comprising four radial struts. The skilled person will understand however that the number of struts and their disposition could easily be modified, according to the circumstances and the destination of the implantable device 2 .
[0028] The link section 20 is located at one extremity of the core 10 , and its function is to allow repeatable engagement and connection with the grasp section placed on the delivery/recovery apparatus 3 , also visible on FIG. 1 . The link section comprises, in this embodiment of the invention, a round/cylindrical head 21 , joined to the core by a relatively narrow neck 22 .
[0029] The delivery/recovery apparatus 3 comprises a flexible catheter 40 , enclosed in a flexible sleeve 35 . On the tip of the catheter 40 is fixed a grasping device composed by the four flexible fingers 45 . According to the relative position of the catheter 40 in the sleeve 45 the fingers can be retracted inside the sleeve 45 , in which case they assume the closed configuration represented in FIG. 1 , or they can extend forward from the sleeve 45 , in which case their elasticity forces them in the open configuration shown on FIG. 2 c.
[0030] The functioning of the implantable device 2 and of the apparatus 3 will now be explained in relation with FIGS. 2 a - 2 d , showing a typical implantation sequence.
[0031] In FIG. 2 a is visible the implantable device 2 , connected to the catheter 40 by the fingers 45 closed on the neck 22 of the link section. The device 2 is fully retracted inside the sleeve 35 .
[0032] In this configuration the sleeve 35 is inserted into the human or animal body, and guided until the tip of the apparatus 3 , now containing the device 2 , is at the place chosen for the implantation. The progress of the device into the body can for example be monitored and followed using conventional X-ray techniques. To this effect the device 2 and the delivery/recovery apparatus 3 may be equipped with radio-opaque marks.
[0033] Once the position of the device 2 is satisfactory, the operator retracts the sleeve 35 ( FIG. 2 b ). The device 2 is still connected and axially maintained by the catheter 40 . In this way the struts 6 , now free from the sleeve 35 , open themselves and anchor the device 2 inside the blood vessel 3 .
[0034] By continuing the retraction of the sleeve 35 the fingers 45 finally get free, and open themselves ( FIG. 2 c ). The device 2 is now detached from the catheter 40 .
[0035] Finally the catheter 35 is pulled back, and the fingers 45 retracted inside the sleeve 35 . In this configuration the apparatus 3 can be extracted from the body, leaving the implantable device 2 in place in the body lumen 8 .
[0036] A recovery sequence involves all the above steps in reverse order. Initially the delivery/recovery apparatus 3 is inserted in the body lumen 8 , with the grasp section fully retracted inside the sleeve 35 ( FIG. 2 d ). The catheter 45 is then pushed out of the sleeve 35 in order to expose and open the fingers 45 ( FIG. 2 c ). During this phase the fingers 45 touch the walls of the body lumen 8 , and align the tip the catheter 35 with the axis of the body lumen, simplifying the connection between delivery/recovery apparatus 3 and the implantable device 2 . Once the tip of the catheter 35 is in contact with the link section of the implantable device, the sleeve 35 is advanced ( FIG. 2 b ), in order to close the fingers 45 on the neck 22 , thereby locking and aligning the catheter 35 and the implantable device 2 . Finally the edge of the sleeve 35 enters in contact with the struts 6 and forces them in the compressed configuration. The device 2 is now released from the lumen 8 and can be recovered inside the sleeve 35 .
[0037] The grasp section of the delivery/recovery apparatus 3 can of course take also other forms, different from the hook-shaped fingers of FIG. 1 . In a variant of the present embodiment represented on FIG. 5 , the grasp section comprises two rectangular or oval loops 49 .
[0038] The link section 20 of the device 2 can also take other forms than the round head if FIG. 1 . For example, in the variant of FIG. 6 , which will be explained in more detail later, the head 21 has the shape of a ball. In the example visible on FIG. 8 the link section comprises a wire loop 221 .
[0039] The present invention is however not limited to the shapes described here by way of example for the join section of the device 2 and the grasp section of the delivery/recovery apparatus 3 , but comprises as well all the many different shapes adapted to interoperate together for the realization of the invention.
[0040] The device 2 further comprises at least a permanently attached sensor 70 . For example the sensor 70 may measure a physical property, like blood pressure sensor, fluid flow, temperature or electric heart or muscle activity. The sensor 70 may also record a chemical blood parameter, like pH, glycaemia, electrolytes or gas concentration.
[0041] Preferably the sensor 70 communicates with an external readout unit (not shown) via a wireless connection. In this way the parameters acquired by the sensor 70 can be accessed whenever necessary, or automatically logged on a periodical basis in the readout unit for later analysis.
[0042] If requested, the readout unit may be arranged to trigger an alarm signal in case an abnormal situation, calling for urgent medical care is detected.
[0043] Advantageously the wireless link between the external readout unit and the sensor 70 could also provide the necessary energy source for the sensor operation. The link could for example comprise a backscattering passive transponder.
[0044] In this variant of the invention, the sensor 70 is only active when the readout unit sends an electromagnetic flux toward the implanted device 2 . In this case the electrical signal picked up by the transponder antenna serves, after rectification and conversion, to supply the sensor 70 . The requested measurement is then sent back to the readout unit by backscattering modulation or other transmission techniques.
[0045] Other wireless communication techniques, like for example HF, acousto-magnetic, electromagnetic, swept-RF or Macro-wave or others are also possible and comprised in the present invention.
[0046] By using a passive transponder, the need of an energy source in the implantable device is avoided, thus reducing the size of the device 2 and the hazard connected with electrochemical batteries. Autonomous energy sources may however also be employed, according to the circumstances.
[0047] In an alternative, not represented, variant of the present invention, the data recorded by the sensor 70 are logged in a permanent memory included in the implantable device 2 . In this case no real-time telemetry link is required. Instead the data are analyzed in a second moment, when the implantable device 2 is removed from the patient's body.
[0048] According to this variant embodiment of the invention, the implantable device 2 may comprise an autonomous source of electrical energy, for example an electrochemical battery. Alternately, the implantable device 2 may be alimented by an external source, via a magnetic link or another wireless energy transmission technique.
[0049] Advantageously, the sensor 70 may communicate with another implanted device present in the patient's body, via a wireless connection. Thanks to this communication, an implantable device may adapt its operating parameters depending on data received from the sensor 70 . Such implantable device may include for example a cardiac stimulator, a drug delivery device, or any other device. The data transmitted via the wireless link by the sensor 70 to the implantable device may be representative of any significant body parameter like for example blood or fluid pressure, sugar concentration, or any other significant clinical parameter.
[0050] Advantageously the device of the invention comprises also a radiofrequency antenna for the wireless connection. According to circumstances the antenna may be incorporated in the device body or comprise for example a flexible wire protruding from the device body, a mesh antenna, a linear antenna or others.
[0051] According to another embodiment of the present invention, represented on FIG. 3 , the sensor 70 is not rigidly joined to the device 2 , but rather connected to it by a flexible tether 50 .
[0052] This embodiment of the invention allows monitoring of body parameters in places that, due to their conformation or for other reason, would not be suitable for directly placing a device. An example of application for this embodiment of the present invention would be the monitoring of blood pressure in an aneurism
[0053] According to another embodiment of the present invention not represented in the figures, the device 2 includes a reservoir of a biologically active substance, which can be selectively put in fluid contact with the body lumen 8 by an appropriate command from an external unit in wireless communication with the implantable device 2 . This embodiment of the invention comprises a hollow reservoir and an electrically actionable valve realized with known micro-fluidic and MEMS (microelectromechanical systems) techniques, for example by 2D or 3D photolithography, or by a LIGA process.
[0054] In another variant embodiment the device may contain elements loaded with a biologically active substance, which is passively released in the body, until the device is extracted, or the supply is used up.
[0055] According to the embodiment of the invention represented on FIGS. 4 a and 4 b , the body of the implantable device 2 comprises a tubular elastic mesh 150 of biocompatible wire. The tubular mesh 150 has an expanded configuration, allowing it to adhere closely to the inner walls of the blood vessel 8 , yet is sufficiently elastic to be compressed inside the sleeve 35 of the delivery/recovery apparatus 3 . The link section consists, in this embodiment of the present invention, of a ball 21 , connected to the mesh 150 by at least one wire 220 , as it is visible on FIG. 6 .
[0056] According to another embodiment of the present invention represented on FIG. 7 , the device 2 comprises a plurality of curved smooth membranes 170 joined together by a common central edge 175 . The outer edges 172 of the membranes 170 lie, in the deployed extended configuration, on the inner walls of the blood vessel 8 , thereby securing the device 2 in place. To recover the device 2 the membranes 170 are bent elastically and/or rolled one on each other, by the combined action of the catheter 35 pulling on the ball 21 and of the edge of the sleeve 35 pushing on the wires 220 , until the device 2 is fully retracted inside the sleeve 35 . In this particular embodiment, the exposed surfaces are smooth and parallel to the fluid current, thereby opposing a low flow resistance, without disturbing laminar flow.
[0057] According to another embodiment of the present invention represented on FIG. 9 , the device 2 comprises two flexible lateral plates 160 , having a cylindrical surface, joined by the triangular or conical flexible surfaces 163 . In the expanded state the lateral surfaces 160 contact the inner wall of the body lumen 8 and maintain the device in the desired position. The creases between lateral plates 160 and the connecting surfaces 163 can bend, compressing the device 2 inside the sleeve 35 , as in the other embodiments.
[0058] According to another embodiment of the present invention represented on FIG. 10 , the device 2 comprises an elongated core 10 and at least one flexible wire 180 comprising straight and bent sections, whose flexibility allows a compressed configuration for fitting inside the sleeve 35 and an expanded configuration for anchoring inside the body lumen 3 having a lateral dimension larger than the lateral dimension of said compressed configuration.
[0059] FIG. 11 represents a further embodiment of the present invention, in which the implantable device comprises two flexible arms 66 , joined as to form a flexible “U”, and the join section fixed on the curved section of the “U”
[0060] FIG. 12 shows an application of the present invention in which the implantable device 2 is inserted in a permanent or semipermanent angioplasty stent 15 . In this case the particular embodiment of FIG. 11 is shown, inside a tubular stent 15 . The skilled person will understand, however, that all presented embodiment of the invention may be adapted for use in this manner. In this particular application, the device of the invention can for example be placed for a limited time, after an angioplasty operation, in the expanded body vessel. Thanks to this aspect of the invention it is possible to monitor or log blood pressure, flow constriction, or other clinical parameters, or deliver drugs in situ.
[0061] Independently from the expansive action of the stent 15 , it may be desirable in certain cases to provide for an interface element 15 between the implantable device 2 and the walls of the body lumen into which the device 2 is placed. The interface element 15 may include for example a cylindrical sleeve as represented on FIG. 12 , optionally treated with appropriate substances for preventing or limiting a tissue growth at the implant site, thereby reducing the risk of embolism during the recovery of the device 2 .
[0062] The interface element 15 may be recovered with the device 2 , or may be left in situ permanently or until a later moment. Other forms of interface elements are however possible and readily devisable by the skilled in the art.
[0063] A further embodiment of the present invention is now described with reference to FIG. 13 . According to this embodiment the implantable device 2 comprises an embolism protection device 310 .
[0064] During the positioning or recovery of the device of the invention, there is a risk that emboli dislodged by the procedure will migrate through the circulatory system and cause infarction, strokes or other medical conditions. Similarly dangerous conditions may arise while the device is implanted in the foreseen location, according to the circumstances.
[0065] The protection device 310 prevents emboli from migrating through the circulatory system and may consist in a filtering device, capable of capturing eventual embolic particles, while allowing essentially unimpeded blood flow. An example of such vascular filters is described, among others, in International Patent Application WO03/011185, which is hereby incorporated by reference. Many other filters means are however possible and comprised in the scope of the present invention. Other devices, like for example balloons or other occlusion means are also enclosed in the scope of the present invention. According to the necessity, the protection device can be positioned distally or proximally with reference to the device body 10 .
[0066] One advantage of the present invention is that the implantable intraluminal or intravascular device 2 is releasably connected to a positioning apparatus for permanent or semipermanent delivery within a body lumen. It is however to be understood that the implantable device of the invention can as well be employed, if required or convenient, while still connected to the positioning apparatus 3 . For example during the positioning or retrieval phases, or when a temporary diagnostic or therapeutic action is required.
[0067] The implantable device 2 of the invention may further provide an attachment site for connecting a removable part thereto. The removable part may include for example a drug-release element, which need to be renewed after a certain time, or comprise the sensor 70 , or also comprise additional sensors or other diagnostic or clinical devices which can be connected to the implantable device 4 and removed at will by appropriate endoscopic or surgical techniques.
[0068] The attachment site may comprise any suitable attachment means, for connecting the removable part and the sensor. For example said attachment means may comprise a threaded connection or a clip connection, or others.
[0069] The present invention has been described by means of specific examples and embodiments. It will be understood however, by the skilled of the art, that various alternatives may be used and equivalents may be substituted for elements described herein, without deviating from the scope of the invention. Modifications may be necessary to adapt the invention to a particular situation or to particular materials or sensors without departing from the scope of the invention. It is intended that the invention not be limited to the embodiment presented herein by way of the example, but that the claims be given their broadest interpretation to cover all the embodiments, literal or equivalent, discussed herein. | Instrumented retrievable implantable device ( 2 ), comprising an expandable section, for placement inside a body lumen, preferably in a blood vessel. The device ( 2 ) comprises a joined sensor ( 70 ) for monitoring one or more physiological parameter for diagnostic or therapeutic purposes. Data access is assured by a passive RF transponder, in communication with an external readout unit or an implanted device, providing as well to the energy supply of the sensor ( 70 ). The shape of the device of the invention ( 2 ) allows repositioning and retrieval by micro-invasive methods, by means of a link section ( 20 ) capable of being coupled with a grabbing device ( 45 ) mounted on a catheter ( 40 ). | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation of U.S. patent application Ser. No. 12/240,853, entitled “NATURAL LANGUAGE PARSERS TO NORMALIZE ADDRESSES FOR GEOCODING,” filed Sep. 29, 2008, which claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 60/976,341, entitled “Method for Building Natural Language Geocoders by Example,” filed on Sep. 28, 2007; the disclosures of each of the foregoing applications are incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to geocoding and more specifically to natural language parsers/splitters to normalize addresses.
2. Description of Related Art
Geocoding is the process of finding associated geographic coordinates (often expressed as latitude and longitude) from other geographic data, such as street addresses, or zip codes. With geographic coordinates the features can be mapped and entered into Geographic Information Systems (GIS), or the coordinates can be embedded into media such as digital photographs via geotagging. Generally, a geocoder is a piece of software or a (web) service that helps in this process.
Yet, there are many different addressing schemes and languages in the world. Hence, there is a need for a system that could understand those addressing schemes and languages, as well as all the different ways a human might write or input an address into a computer. The latter is referred to as “natural language” (or “ordinary language”), which is a language that is spoken, written, or signed by humans for general-purpose communication and often includes informal and/or abbreviated syntax, and relaxed adherence to grammatical rules. For example, when a user inputs an address, that input often does not adhere to standardized address formats processed by machines.
U.S. Pat. No. 7,039,640 to Miller et al., the disclosure of which is incorporated by reference herein in its entirety, discloses a system and method for geocoding diverse address formats. A single geocoding engine is taught that is allegedly capable of handling various address formats in use in different countries and jurisdictions. This engine uses country/jurisdiction specific parsers for isolating generic address components, e.g., street number, street, city, country, and postal code.
Conventionally, country/jurisdiction specific parsers are generated either by hand, or by manually describing the grammar and using a parser generator to construct a parser from the context free grammar. The former is extremely tedious and is prone to errors. As changes are made to improve hand crafter parsers, care needs to be taken not to upset addresses that previously could parse correctly. Manually describing the grammar as a context free grammar has its limitations as well, as ambiguous input (which is very common with street addresses) is not easily handled by this technique and as such the hit rate, i.e., matches between addresses input by a user and addresses accepted and known to a computer, is much lower.
SUMMARY OF THE INVENTION
The present invention overcomes these and other deficiencies of the prior art by automating the parser creation process. Particularly, the present invention provides a technique for building natural language parsers by implementing a country and/or jurisdiction specific set of training data that is automatically converted during a build phase to a respective predictive model, i.e., country specific natural language parser. The predictive model can be used at a later time without the training data to quantify any input address. This model may be included as part of a larger Geographic Information System (GIS) data-set or as a stand alone quantifier. The build phase may also be run on demand and the resultant predictive model kept in temporary storage for immediate use.
In an embodiment of the invention, a method for normalizing an input address comprises the steps of: receiving an input address, parsing the input address into components, classifying each component according to one or more predetermined regular expressions and a lexicon of known tokens, thereby generating classified components, and executing a predictive model to associate each classified component with a unique address field. The method may further include the step of executing the predictive model to generate a probability associated with each unique address field. The predictive model can be generated from a training file comprising the one or more predetermined regular expressions and exemplary tokens. The training file may be associated with a particular country or jurisdiction. The step of classifying each component can be performed by matching a component to the one or more predetermined regular expressions only when there is no match between that component and the lexicon of known tokens. The predictive model may be associated with a particular country or jurisdiction. The predictive model comprises a table of probabilities associated with the unique address fields.
In another embodiment of the invention, a method of constructing a natural language parser comprises the steps of: loading a training file defining an acceptable format for one or more regular expressions and comprising exemplary address field and token pairs; parsing the training file into a number of tokens; classifying the tokens according to a lexicon of known tokens and the regular expressions; and generating a predictive model that defines a probability for each of one or more address fields that may be associated with a given token. The method may further include the step of identifying the most likely address field for each of the classified tokens. The training file and predictive model are specific to a unique country or jurisdiction. The method may further include the step calculating the probability based on a number of times each classified token ends up in a given address field. The training file may indicate the relative positions of each exemplary token.
In another embodiment of the invention, a computer readable medium encoded with computer readable program code, the program code comprises the instructions of: parsing an input address into components, classifying each component according to one or more predetermined regular expressions and a lexicon of known tokens, thereby generating classified components, and executing a predictive model to associate each classified component with a unique address field. The computer readable medium may further comprise the instruction of executing the predictive model to generate a probability associated with each unique address field and/or the instruction of generating the predictive model from a training file comprising the one or more predetermined regular expressions and exemplary tokens. The training file is associated with a particular country or jurisdiction. The instruction of classifying each component may be performed by matching a component to the one or more predetermined regular expressions only when there is no match between that component and the lexicon of known tokens. The predictive model may also be associated with a particular country or jurisdiction. The predictive model may comprise a table of probabilities associated with the unique address fields.
The present invention provides numerous advantages over conventional approaches as it removes the tedium of building a country and/or jurisdiction specific parser for each respective addressing scheme. Also, training the parser becomes much less of a balancing act—in conventional parsers, if you make a change so that the parser can recognize a new street type, it may start incorrectly parsing some addresses that previously it parsed correctly, so every change that is made has to be made more and more carefully so as to not upset addresses that already parse correctly. The probabilistic nature of the predictive model allows ambiguities in the input to be naturally handled and the most likely parsing(s) can be found.
The foregoing, and other features and advantages of the invention, will be apparent from the following, more particular description of the preferred embodiments of the invention, the accompanying drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, the objects and advantages thereof, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:
FIG. 1 illustrates process for normalizing addresses according to an embodiment of the invention;
FIG. 2 illustrates an exemplary training file for a unique jurisdiction, i.e., Australia, according to an embodiment of the invention;
FIG. 3 illustrates a predictive model according to an embodiment of the invention; and
FIG. 4 illustrates an exemplary training file used to generate the predictive model of FIG. 3 .
DETAILED DESCRIPTION OF EMBODIMENTS
Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying FIGS. 1-4 . The embodiments of the invention are described in the context of geocoding normalized address fields. Nonetheless, one of ordinary skill in the art readily recognizes that the present technique may be applied to other applications that use normalized data fields as input.
The present invention provides a software technique for automatically generating natural language country and/or jurisdiction parsers that can understand all of the ways a person might write an address, as well as the many various addressing formats in use around the world. Any computer language may be used to implement the present software, the identification of which is apparent to one of ordinary skill in the art—nonetheless, the following exemplary embodiments are described in the context of the C-sharp (“C#”) programming language. This software may be implemented on any type of computer hardware including, but not limited to a personal computer, mobile computer, workstation, and server, the implementation of which is apparent to one of ordinary skill in the art.
FIG. 1 illustrates a process 100 for normalizing addresses according to an embodiment of the invention. The method 100 comprises a number of steps, first starting with the creation of one or more training files. For example, a training file is created (step 110 ) for each unique addressing scheme and/or jurisdiction. The training file is then read by a computer processor, which in turn uses such to generate (step 120 ) a respective predictive model. The predictive model is then stored (step 130 ) within memory or suitable storage means, the identification and implementation of which is apparent to one of ordinary skill in the art. The predictive model is then read (step 140 ) into a computer processor and used (step 150 ) for address parsing of a user's inputted address into normalized address fields.
FIG. 2 illustrates an exemplary training file 200 for a unique jurisdiction, i.e., Australia, according to an embodiment of the invention. Particularly, the first four lines 201 - 204 define the acceptable syntax for regular expressions (“regexes”) for a generic parser. These regular expressions are presented in .Net syntax, the implementation of which is apparent to one of ordinary skill in the art. During parsing, an given input address is broken up into tokens on separator characters such as spaces, commas, semicolons, colons, spaces, etc. or a combination thereof. In a preferred embodiment, commas are used as separator characters. The generic parser works by using a lexicon of known tokens and the regular expressions to classify each token before sending the string of classified tokens to the predictive model to calculate the most likely categories for each token.
Particularly, these tokens are looked up in the lexicon, which is built during import of the training file. The difference between a regular expression and a token is that a regular expression is a concise language for expressing a set of strings, whereas a token is the constituent part of a complete input. The parser is responsible for splitting the input up into meaningful “tokens”—for example “Street,” or “Main”—or even “Santa Monica” as a single token. A string is said to match a regular expression if that string is in the set of strings defined by that regular expression. After the input string is “tokenized” it is matched against the lexicon and/or the list of regexes until a match is found.
In an embodiment of the invention, the lexicon is built during import of street data from shapefile format into the GeoBase (GBFS) format, the implementation of which is apparent to one of ordinary skill in the art. The underlying street data has each component stored separately (e.g., W/Main/St/Santa Monica), which means during analysis the category that a given token appears in most frequently is the one that it will be inserted into the lexicon as, e.g., Santa Monica may be both a City and a BaseName (as in Santa Monica Blvd), however, it is much more common in the data as a city name, so that is what it is classified as in the lexicon.
If the parsed token cannot be found in the lexicon, it is matched against the regular expressions until one succeeds. The label at the end of the regexes is then applied to that token (e.g., POSTCODE or XNUM). XNUM in this context is the classification given to tokens that match the regex on line 202 . This is later used by the predictive model to assign a final address field (probably street number in this exemplary case) to the token. The classification given by the lexicon or regex does not necessarily correspond directly to an address field. The predictive model may indicate that a token classified as City (e.g., Santa Monica) should actually be a Basename because of context, for example.
Only four regexes are shown in FIG. 2 because the majority of tokens will be classified by the lexicon. Also, there are a number of implied regexes that don't need to be specifically included in the training file. These are:
^[0-9]+$,NUM ^\d+[NSEW−]\d+$,BNUM ^\S\d+$,BNUM ^[NSEW]\d+[NSEW]\d+$,BNUM ^[NSEW]\d+$,BNUM ^\d+[EW]$,BNUM ^[a-z\−\s]+$,ALPHA ^[^,]+$,ALPHANUM
The remainder of the file 200 describes the training proper. Each line consists of a set of comma separated values. Each value, e.g., BASENAME, TYP_AFT, CITY, POSTCODE, NUM) is a Label:Token pair. For example, in line 205 , the first Label:Token pair is BASENAME:Elizabeth, such that “BASENAME” is a Label and “Elizabeth” is the token. The token from each pair is labeled using the lexicon or a regular expression as described above. This label is then compared to the label in the training to build a table of probabilities for the predictive model. For example, referring again to line 205 , which fully reads:
BASENAME:Elizabeth,TYP_AFT:St,CITY:Waterloo,POSTCODE:2017
The “Elizabeth” token is looked up in the lexicon and found to be a known token referred to as BASENAME. This matches the label in the training file 200 so at this point the BASENAME label is considered to be BASENAME 100% of the time.
Referring to line 206 , which reads:
NUM:54,BASENAME:Terrace,TYP_AFT:Road,POSTCODE:6000,CITY:Perth
Here, the BASENAME is “Terrace.” When this is looked up in the lexicon it is reported as TYP_AFT, as it most commonly appears as a street suffix. This contradicts the existing probabilities and the model is updated so that the BASENAME position is filled by a token labeled BASENAME 50% of the time and a token labeled TYP_AFT 50% of the time. In this way, a representative list of addresses will likely set BASENAME to 80-90%, and other token types the remainder of the time.
The probabilities are calculated based on the number of times each classification ends up in a given address field during training. So in the example, the first line 205 has Elizabeth, which is classified as BASENAME by the lexicon, and BASENAME by the training data. This gives BASENAME-BASENAME a 100% hit rate. The second line 206 classifies Terrace as TYP_AFT, but the training puts it into the BASENAME address field, so now BASENAME-BASENAME happens 50% of the time, while TYP_AFT-BASENAME happens the other 50%. Once the entire training set is processed, most datasets come out to 80-90% because typically, tokens in the BASENAME address field will have been classified as BASENAME in the first instance, by the lexicon.
Each output position or token (NUM, BASENAME, CITY, etc.) has its table of possible input labels and table of probabilities populated by the end of the training file. The table of probabilities is in memory at this point and is saved into the resulting street dataset at the end of the training session. The table of probabilities is used to construct the predictive model, e.g., the graph as shown in FIG. 3 , which is further described below.
Another function of the training file is to indicate the relative positions of each token. For example, referring to line 207 , which reads:
CITY: Sydney
This line determines that the very first token may be the city. Whereas, referring to line 208 , which reads:
NUM:637,BASENAME:Elizabeth,TYP_AFT:St,CITY:Waterloo,POSTCODE:2017,STATE:NSW
determines that the input may in fact begin with a number, and that the sequence NUM,BASENAME,TYP_AFT,CITY,POSTCODE,STATE is valid. In this way, all training lines, e.g., 208 - 219 , are used to determine all the possible ‘next positions’ from any given output. For example, BASENAME may be validly followed by TYP_AFT, SUBURB, CITY or POSTCODE in line 208 .
FIG. 3 illustrates a predictive model 300 according to an embodiment of the invention. This graphical depiction of the predictive model 300 is generated from a slightly different training set, which is shown in FIG. 4 , than that shown in FIG. 2 . Each box, i.e., boxes 310 - 380 , consists of two lines. The first line is the address field and the second line is a set of token classifications that may validly be seen at that position. There are two sets of probabilities in this graph: (1) the probabilities on the edges and (2) the probabilities within a single address field box. All the edges coming out of a given address field have probabilities that sum to 1. Also, all the token classification probabilities within a single address field have probabilities that sum to 1.
Consider the address “101-103 Liverpool Road, 6000 Perth” as an input address for the predictive model 300 . This is split into five tokens and each token is classified. The first token “101-103” isn't in the lexicon so it will match the XNUM regex. Liverpool is in the lexicon as a CITY. Road is in the lexicon as a TYP_AFT (“type after”). 6000 isn't in the lexicon, but will match the POSTCODE regex, and PERTH is in the lexicon as a CITY. Therefore, this address will have the tokenized classification of: XNUM CITY TYP_AFT POSTCODE CITY.
It is now up to the predictive model 300 to decide which address field label each token truly belongs in. The first step is simple—the only place XNUM appears is as a classified token 312 on the NUM address field 310 directly below the start state. There is no other possible location for this, so 101-103 is put into the NUM address field 310 , and the probability becomes 0.80*0.06=0.048 (so far).
Next we must place the CITY token according to the predictive model 300 . The only address field that can follow NUM, according to this model 300 is the address field 320 pertaining to BASENAME, and this field can accept CITY as a classified token 322 , so our address field BASENAME gets the value Liverpool, and the probability is 0.048*1.00*0.22=0.01056.
Next we have a TYP_AFT token from the input address. There are two possible paths A and B to follow now in the predictive model 300 . The predictive model 300 could put it into the TYP_AFT classified token 332 in the address field 330 following path A, or it could be put into the STREET address field 340 following path B. The latter is due to an error in the training file—there is no recognized address field named STREET. This error is presented as an example of the invention's robustness, and will not cause a problem though, because the parser will see it as such a low probability to not be a likely candidate.
The action taken when faced with a choice of address fields like this is to choose both, continue on each branch until the end of the address, and finally take the n highest probability parsings. So in this example, the predictive model 300 would take the TYP_AFT address field branch 330 along path A for a probability of 0.01056*0.89*0.50=0.0047 (with 2 significant figures), and also the STREET address field 340 along path B for a probability of 0.01056*0.06*1.00=0.00063 (2 significant figures). At this point, there are two potential branches and the predictive model 300 will continue with both until the end (or until the probability reaches zero, at which point we can give up on that branch).
Next, we have a POSTCODE token. Our first possible branch C can put this into a POSTCODE field 370 , with a probability of 0.0047*0.13*1.00=6.1×10 4 . Our second branch from the STREET address field 340 has no output edges available, so any more tokens would be considered a probability of zero. At this point we can give up on the second parsing, which was following path B, and continue on with the first parsing (following path A and branch C), which is currently: NUM:101-103, BASENAME: Liverpool, TYP_AFT:Road, POSTCODE:6000, ??:Perth.
Finally, from the POSTCODE field 370 , it can be followed by a CITY token in the CITY field 360 along path D with a probability of 6.1×10 4 *0.38*0.77=1.79×10 4 , which is our final probability for the parsing:
NUM: 101-103 BASENAME: Liverpool TYP_AFT: Road POSTCODE: 6000 CITY: Perth
All other known address fields (SUBURB 350 and STATE 380 ) are empty for the given input address.
FIG. 4 illustrates an exemplary training file 400 for a unique jurisdiction, i.e., Australia, according to an embodiment of the invention. This training file was used to generate the predictive model 300 as described and implemented above.
The invention has been described herein using specific embodiments for the purposes of illustration only. It will be readily apparent to one of ordinary skill in the art, however, that the principles of the invention can be embodied in other ways. Therefore, the invention should not be regarded as being limited in scope to the specific embodiments disclosed. | The present invention provides a technique for building natural language parsers by implementing a country and/or jurisdiction specific set of training data that is automatically converted during a build phase to a respective predictive model, i.e., an automated country specific natural language parser. The predictive model can be used without the training data to quantify any input address. This model may be included as part of a larger Geographic Information System (GIS) data-set or as a stand alone quantifier. The build phase may also be run on demand and the resultant predictive model kept in temporary storage for immediate use. | 6 |
FIELD OF THE INVENTION
This invention relates to devices for monitoring wetness, particularly in diapers, and to diapers containing such devices.
BACKGROUND OF THE INVENTION
Various methods and means have been developed for monitoring moisture or wetness in diapers. The purpose of such devices is to set off an alarm when a diaper becomes wet. This permits a mother to tend to a newborn infant or toddler. However such devices have disadvantages in that they may require conductors to pass mechanically through the diaper's plastic outer sheath, may subject the skin of the wearer to direct voltages from a voltage source, may be sensitive only in a limited area, may accidentally respond to the wearer sitting on a wet or metal bench or park slide, or have other drawbacks.
SUMMARY OF THE INVENTION
According to an embodiment of the invention, a pair of spaced electrodes within the area subject to wetness couple non-conductively with a sensor protected from wetness, and an alarm sounds in response to moisture decreasing the resistance between the electrodes. For example the electrodes project into the absorbent material of a diaper and extend along the inside of the diaper sheath opposite a pouch on the outside of the sheath. The pouch contains a sensor capacitively coupled to the electrodes.
The various features of novelty which characterize the invention are pointed out in the claims forming a part of this specification. Objects and advantages of the invention will become evident from the following detailed descriptions of embodiments of the invention when read in light of the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a diaper embodying the invention.
FIG. 2 is a perspective view of FIG. 1.
FIG. 3 is circuit diagram of a sensor used in FIGS. 1 and 2.
FIGS. 4 and 5 illustrate an embodiment of a pouch in FIGS. 1 and 2.
FIG. 6 is a plan view of the rear of an embodiment of a diaper with a pouch on the outside and containing a sensor.
FIG. 7 is an frontal elevation of the rear of the diaper, when opened, in FIG. 6.
FIG. 8 is a plan view of the rear of another embodiment of a diaper with a pouch on the outside and containing a sensor.
FIG. 9 is an frontal elevation of the rear of the diaper, when opened, in FIG. 8.
FIG. 10 is a perspective view of a sensor embodying the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In the exploded view of FIG. 1 and the partially-exploded perspective of FIG. 2, a disposable diaper 100 embodying the invention includes an inner sheet 104 of a water-permeable film which overlies a wetness absorber layer 107 of powerfully liquid-absorbent padding or other powerfully absorbent material. In one embodiment the layer 107 may include a gel-forming absorbent resin. An outer water-impermeable electrically-insulating plastic sheath 110 supports two conductive spaced-apart electrodes 114, in the form of metallic or other electrically-conductive strips, that extend along the center of the sheath 110 and in electrical contact with the absorber layer 107. According to an embodiment of the invention, the electrodes 114 pass longitudinally through the layer 107. According to another embodiment, the electrodes 114 are in the form of conductive threads or wires.
The sheet 104 is common to most disposable diapers and is often referred to as cover stock. It is composed of thick porous, relatively hydrophobic, bonded fibers which tend to pass liquid in one direction from the wearer to the absorber layer 107. The urine is held away from the skin by the competition between the highly absorbent layer 107 and the not-so-absorbent sheet 104. In this way the relatively hydrophobic fibers space the wet mass of the layer 107 from the skin of the wearer. This keeps the skin dry even when the wearer has wet the diaper. The sheet 104 may be omitted in training diapers that intend to make the wearer uncomfortable when the diaper is wet. The diaper is worn in the usual fashion.
The electrodes 114 terminate in widened pairs of adjacent fixedly spaced electrically-conductive pads 117 on each end. The pairs of pads 117 at each end are printed on the sheath 110 or are bonded to the sheath 110 so they maintain a fixed position on the sheath 110 and so they are in intimate contact with the sheath. According to another embodiment, the pads 117 are otherwise deposited or applied, such as by selective metallization, or carbonization using a laser. Bonded to the outer face of the sheath 110, directly opposite the pads 117 at each end of the sheath, are pouches 120. Each pouch 120 is adapted to receive a removable sensor 124 having thin electrically-conductive rectangular planar members or surfaces 127. Although two pouches 120 exist, only one pouch receives a sensor 124. When two pouches exist, the selection of the pouch which receives the sensor 124 depends upon the preferences, e.g. based on the comfort, of the user.
The position of each pouch 120 is such as to place the pair of planar members 127 on the sheath 110, directly behind a pair of the pads 117 without overlapping one member 127 with two of the opposing adjacent pads 117 or vice versa. One of the pairs of pads or members is larger than the other to permit tolerance in placement.
According to an embodiment, each pouch 120 is composed of or contains, in some portion, resilient material (not shown) to press the members 127 into position against the sheath 110 when the diaper is worn. The members 127 do not electrically contact the pads 117, rather the sheath 110 separates the members from the pads. When a sensor 124 sits in the pouch 120, the pair of members 127 of the sensor 124, and the opposing pair of pads 117 form two adjacent capacitors.
According to an embodiment, the sides of the sensor 124 are tapered to facilitate insertion in the collapsed pouch. The faces of the sensor 124 may also be tapered.
As shown in FIG. 2, suitable fastening strips 130 secure the diaper in operable condition, and the sensor 124 is placed in the pouch 120 at the rear or front of the diaper. When a user wears and wets the diaper, the liquid passes through the sheet 104 into the absorber layer 107 and to the sheath 110. The liquid then electrolytically short-circuits the electrodes 114. Hence the electrodes 114 operate as a conductive switch which is open, i.e. non-conductive, in a dry diaper and closed, i.e. conductive, in a wet diaper.
According to another embodiment of the invention, the diaper contains only one pouch 120. The diaper may further comprise other accessories as may be necessary or desired, such as elastic electrodes for close fit to the wearer, tapes, tabs, snaps or the like for fastening the diaper in place upon the wearer, for example.
The sensor 124 contains an oscillating voltage or pulse source, preferably one having a low duty cycle, which capacitively couples to the members 127 to the pads 117 using the sheath 110 as the dielectric medium, and an alarm device which responds to the source. The spaced electrodes 114 form a switch that remains open (non-conductive) when the diaper is dry. The sensor 124 is set so varying current from the source cannot pass through the open switch formed by the electrodes 114. When the diaper is wet, the electrolytic action of the urine in the diaper contacts the electrodes 114 and closes the switch, i.e. makes it conductive across the gap between the electrodes 114. The sensor 124 is set so varying voltage of the source then passes a current from the sensor 124 through the capacitor formed by one member 127 and the opposing pad 117, through one electrode 114 through the electrolytically conductive gap between electrodes to the other electrode 114, through the capacitor formed by the second of the pair of pads 117 and the second of the pair of members 127, back to the sensor. The resulting current triggers an alarm which, according to one embodiment, energizes a piezoelectric sounder and plays a tune or makes some other sound such as a beep.
According to another embodiment, the alarm takes the form of a blinking or turned on light, such as an LED. According to another embodiment, the alarm is transmitted by radio waves, infra-red radiation, or other means to a remote position where an attendant can monitor a number of children or other wearers.
The alarm, in the form of a sound or light, informs the wearer, who may be an infant being trained, or the infant's parent, that the diaper is becoming wet. This allows prompt action. A sound or light alarm may for example make the infant in training associate its urges with its training needs. The sound or light can also serve to notify an infant's parent that the child's diaper needs changing. A sound or light alarm can inform a toddler's attendant of these needs. A sound alarm can be an aid in enuresis training. A light alarm can also warn an elderly incontinent or handicapped person without sensation in the peritoneal area of an incident, or inform a caregiver of the need for changing.
The sensor 124 sets an alarm threshold sufficiently high to prevent a false alarm when a wearer sits on a metal bench or on a wet surface. The capacitive impedance between the pads 117 and members 127 is far less than that between the electrodes 114, even when the electrodes 114 are in the vicinity of metal or a wet s surface. Thus the electrodes 114 present a high impedance unless shorted electrolytically by urine in the diaper. The sensor threshold is sufficiently high to avoid responding to the capacitive coupling between the dry electrodes 114, and yet low enough to respond to the electrolytic conduction between the electrodes 114.
Details of electrical portions of one embodiment of sensor 124 appear in FIG. 3 which includes a low duty-cycle pulser 300. In the pulser 300, an oscillator 304 and divider counter 307, forming part of an integrated circuit or chip, provide the time base for all events in the wetness detection process. In one embodiment, the counter 307 yields a low frequency pulse rate such as 30 Hz to a rising-edge sensitive clock input of a D-type flip-flop 310. A higher frequency pulse, some derivative of the same clock, e.g. 60 kHz to result in a 1:2000 duty cycle, furnishes a reset to the flip-flop 310 a brief period later. As a consequence, the flip-flop 310, which has its data input connected to a positive supply 314, clocks in a logic high which is reset 15 microseconds later by the higher frequency clock. The inverting output Q' of the flip-flop 310 is used and a corresponding 15 microsecond logical low pulse is subsequently generated. This low pulse appears at an inverting amplifier 317 which drives an output pin on the chip, and also appears at a rising-edge sensitive clock input of second flip-flop 320. The buffered output pulse from the inverter 317 passes to an external resistor 324.
The external resistor 324 performs a charge current limiting function in the external R/C circuit formed with the diaper's capacitor-switch network 327. The latter includes a first capacitor 330 formed by one of the members 127 and one of the pads 117 facing each other across the sheath 110, the resistance 334 of the switch formed by the electrodes 114 and the gap between them, and a second capacitor 337 formed by the other of the members 127 and the other of the pads 117 facing each other across the sheath 110.
The voltage at the resistor 324 and across the capacitor switch network 327 also appears at a Schmidt input buffer 340 which produces an output at the D input of the flip-flop 320. The flip-flop 320 is set at power-up to avoid a brief alarm. An output Q' of the flip-flop 320 drives an alarm 344. In the example shown in FIG. 3, the alarm 344 includes a beep-producing piezoelectric crystal PZ, an LED, a radio transmitter RT, an infra-red transmitter IR, a music generating circuit MG, and a tactilely-sensible vibrator VB for enuresis training, any of which may be energized selectively, either alone or all together. The piezoelectric crystal PZ may also produce ultrasonic chirps to communicate the alarm to a remote or bedside receiver. According to other embodiments of the invention, the sensor 124 includes any one or more of the crystal, LED, radio transmitter, infra-red transmitter, music generating circuit, or a tactilely-sensible vibrator without the others. The others may be omitted. Other means of alarm may be used.
In each charge cycle a 15 microsecond current-limited pulse feeds into the capacitor-switch network 327. Assuming the network 327 is initially discharged, it begins to acquire a charge, the terminal voltage of which is a function of the charging source voltage, current-limiting resistor 324, the pulse length, and the capacitance of the series-connected capacitors in the sensor network 327. When the diaper is dry the open circuit at the switch 324 between the electrodes 114 allows the charge across the circuit 327 to rise rapidly toward its peak and beyond the threshold of the Schmidt trigger 340. This places a low at the output Q' of the flip-flop 320. This holds the alarm 320 off. The voltage rises rapidly because, in the proximity of the dry layer 107, the total capacitance of circuit 327 is extremely low, much lower than the series capacitance of the capacitors 330 and 337.
When urine electrolytically shorts the electrodes 114, the total capacitance of network 327 rises substantially to approximately the series combination of the value of the far higher capacitance of coupling capacitances 330 or 337. The voltage across the network 327 then fails to rise above the positive-going threshold of the Schmidt trigger 340. At the next pulse, when the flip-flop 310 resets the flip-flop 320, the output at Q' of the flip-flop 320 goes high and triggers the alarm 344.
More specifically, the resistor 324 has a value such that the network 327 charges to at least the threshold (typically 1.6 volts) of a Schmidt input buffer 340, when the diaper is dry. Thus, at the time of charge termination, and the exact moment when the synchronous rising-edge clock is fed to the second flip-flop 320, the instantaneous level of the output of the Schmidt input buffer 340, being a function of its presently imposed input voltage, is clocked into the sampling flip-flop 320. The resulting state of the outputs of flip-flop 320 indicate the wet or dry state of the diaper in that previous instant and the whole cycle recurs at the previously mentioned 30 Hz rate. The previous state of the detector is held until the next sample in flip-flop 320 and there is no drop out in the case of a continuous wet or dry condition during subsequent re-sampling.
When the diaper is dry, the flip-flop 320 produces a 0 at the Q' output. When the diaper is wet, the charge does not reach the level needed to cause the Schmidt input buffer 340 to apply a 1 to the D input of the flip-flop 320. This produces a 1 at the Q' output of the flip-flop 320 and sets off the alarm 340.
Beside the usual noise-reducing function typical of Schmidt input circuits, this Schmidt input buffer 340 provides an additional effect. As the network charging pulse voltage varies in response the power supply, so too varies the threshold voltage of the Schmidt input buffer 340. This is because the Schmidt threshold points are set by a voltage divider as a ratio directly from the supply voltage. The effect is the reduction of voltage-induced variations in the capacitance threshold as the battery voltage supply weakens.
The low pulse rate at the resistor 324 serves at least two purposes, the first of which is to produce a very long zero-voltage cycle and guarantee the complete discharge of the capacitive sensing network. Each cycle is therefore isolated from the previous one. The low duty cycle assures the bias of the external capacitive network 327, thereby eliminating the need for resistive bias components were, for instance, a comparator used and were the applied waveform a 50% duty cycle square wave. The second purpose is to limit the current required by the overall module circuit in it s repetitive testing cycle. Since the required response is in the order of one or more seconds, the period can be altered to reduce dissipation even further, though the present 10 or so microamps is adequately low.
According to an embodiment, for a duty cycle of 1:2000 for the applied pulse, the values of the resistor 324 and the threshold of the Schmidt trigger can be selected so the average power applied to the series resistor, coupling capacitors, and electrodes approximates 3 nanowatts of power.
FIGS. 4 and 5 illustrate an embodiment of a pouch. Here, an adhesive holds an outer curved flange 407 of an elastic pouch 410 against the outside of the outer water-impermeable electrically-insulating sheath 110. According to another embodiment of the invention, a thermal bond holds the flange 407 to the sheath 110. When the sensor 124 is inserted into the pouch 410, the pouch shapes itself securely about the sensor.
FIG. 6 is a plan view of the rear of an embodiment of a diaper with a pouch 410 on the outside of the sheath 110 and containing a sensor 124. FIG. 7 is an frontal elevation of the rear of the diaper, when opened, in FIG. 6. Here, the thicknesses are exaggerated for clarity. The sensor 124 in the pouch 410 carries the members 127 and presses them against the outside of the sheath 110 opposite the pads 117 printed on the inside of the sheath. A substrate 600 supports the pads 117. A layer 604 common to existing disposable diapers covers the pads 117 and the sheath 110, and provides a mounting surface for an absorber layer 607 corresponding to the layer 107. The latter is also common to most disposable diapers. Covering the absorber layer 607 is a relatively hydrophobic inner sheet 610, also common to disposable diapers, and corresponding to the sheet 104. The relatively hydrophobic fibers space the wet mass of the layer 607 from the skin of the wearer and do not conduct moisture back to the skin. This keeps the skin dry even when the wearer has wet the diaper. The urine is held away from the skin by the competition between the highly absorbent layer 607 and the not-so-absorbent sheet 610.
FIG. 8 is a plan view of the rear of another diaper similar to the diaper in FIGS. 6 and 7, but using bare wires or conductive threads 614 as the electrodes 114. FIG. 9 is an frontal elevation of the rear of the diaper, when opened, in FIG. 8. Here also, the thicknesses are exaggerated for clarity. The bare wires or conductive threads electrically connect to the pads 117 as they are squeezed between the pads and the sheath 110. According to another embodiment, the wires or conductive threads 614 pass through the absorber layer 607.
In the embodiments of FIGS. 6 to 9, as in other embodiments, when the diaper is dry the sensor 124 produces no alarm. The spaced electrodes 114 form the electrically conductive switch that remains open when the diaper is dry. Varying current from the source can then not pass through the open switch formed by the electrodes 114. When the diaper is wet, the electrolytic action of the urine in the diaper contacts the electrodes 114 and closes the switch, i.e. across the gap between the electrodes 114. The varying voltage of the source then passes a current from the sensor 124 through the capacitor formed by one member 127 and the opposing pad 117, through one electrode 114 through the electrolytically conductive gap between electrodes to the other electrrode 114, through the capacitor formed by the second of the pair of pads 117 and the second of the pair of members 127, back to the sensor. The resulting current energizes the alarm which, according to one embodiment, energizes a piezoelectric sounder and plays a tune or makes some other sound such as a beep.
According to another embodiment of the invention, the sheets 104 and 610 are omitted to give the wearer a sensation of wetness and reinforce the alarm.
According to another embodiment, the wires or threads 614 are buried in the absorber layer 607 and fixedly contact a pair of thin plates within the layer 607. The sensor 124 with the members 127 is then insulated and also buried in the absorber layer. According to another embodiment, the arrangement is the same as in FIGS. 1 to 9, but rather than using pouches, the sensor 124 with members 127 is fastened to the sheath 110 by mechanical clips, snaps, or quarter turn locking units on the outside of the diaper.
FIG. 10 is perspective view of an embodiment of a sensor 1000 corresponding to the sensor 124. This includes a housing 1004, an extractor tab 1007, slightly-downwardly tapered sides 1010 and beveled edges 1014. The tapered sides permit alignment on insertion into a pouch. An optional spring loaded switch 1017 is turned on when the sensor 1000 is place in a pouch. The dimensions of the sensor 1000 are such as to fit securely in a pouch. The housing has a rear face 1020 which is curved to furnish a contact force against the sheath 110 and the pouch when place in a pouch.
According to other embodiments, the pads 117 use very thin layers of metals selected for reflectivity as well as oxidation and corrosion resistance. Sputtered or vaporized aluminum covered with nickel avoids oxidation and presents an aesthetically pleasing white appearance outside the diaper.
According to other embodiments, the sensor arrangement is used to inflate a life vest when the vest touches water, in bird feeder water supplies to indicate dry conditions, security doorknobs which respond to skin moisture, liquid level sensors, plant soil moisture indicators, etc.
The invention permits a mother to tend to a newborn infant or toddler, to alert a child during toilet training that it is wetting, to help in enuresis training, and to forewarn the incontinent elderly of a problem before it arises. The invention avoids connecting the source mechanically to the conductors in the diaper from the outside. It also frees the skin of the person wearing the arrangement from direct contact with the voltages that the source applies to the electrodes. Moreover, it avoids a false alarm when the wearer sits on a wet or metal bench, leans on a wet or metal wall, or descends on a metal or wet park slide.
According to other embodiments of the invention, the non-conductive coupling from the sensor to the electrodes is optical rather than capacitive. This involves using an LED and light detector combination on opposite sides of the sheath 110. According to another embodiment, the non-conductive coupling from the sensor to the electrodes is magnetic. This involves applying an electromagnetic field from the sensor in the pouch and then having the field sensed inside the diaper. According to another embodiment, the non-conductive coupling from the sensor to the electrodes is inductive from the sensor to the electrodes.
According to another embodiment of the invention, the speed of the response of the switch formed by the electrodes 114 is varied by changing the relative hydrophobic and hydrophilic correlations of the layers 104 and 107.
The sizes of the members 127 and the pads 117 are sufficiently large, and the face to face spacing between each pad 117 and the opposing member 127 across the dielectric sheath 110 is sufficiently small, so that the capacitances 330 and 337 formed thereby are substantially greater than the very small, almost unmeasurable, stray capacitance between the side-by-side electrodes 114. The Schmidt trigger 340 is set at a low enough value, and the capacitances 330 and 337 are sufficiently high, so that even when a child sits on a wet or metal surface, the stray capacitance across the switch 334 formed by the electrodes 114 does not add enough capacitance to the series circuit 327 to drop the input to the Schmidt trigger below its positive-going threshold. Hence, the flip-flop 320 will not set off a false alarm in response to the wearer sitting on a wet or metal surface. The dimensions ar set to set off the alarm only in response to conduction across the switch 334 formed by the electrodes 114.
While embodiments of the invention have been described in detail it will be evident to those skilled in the art that the invention may be embodied otherwise without departing from its spirit and scope. | A pair of spaced electrodes within an area subject to wetness couple non-conductively with a sensor protected from wetness, and an alarm sounds in response to moisture decreasing the resistance between the electrodes. For example the electrodes project into the absorbent material of a diaper and extend along the inside of the diaper sheath opposite a pouch on the outside of the sheath. The pouch contains a sensor capacitively coupled to the electrodes. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a device for transmitting motion between two components by a cable. More particularly, this invention pertains to a device for automatically adjusting the correct length of the cable assembly that connects the components.
2. Description of the Prior Art
Most cable assemblies that transmit motion from one moveable component to another include means adjacent each end of a conduit for attaching the cable to a support structure and a core element, usually a cable, extending from each end of the conduit. Frequently, however, the end of the cable adjacent one of the components to be moved does not extend from the conduit beyond a fixed mounting point the proper distance for attachment to the component. It is desirable to adjust the effective length of the assembly by changing the position of one end of the cable after the assembly is installed by changing the length of the path over which the conduit extends. Usually this path has curves or bends whose lengths are reduced by increasing the length of the conduit that extends beyond the mounting point.
However, once the assembly is adjusted, it is usually difficult to release the locking member from engagement on ratchet teeth formed on a fitting that is secured to the conduit to reposition or readjust the assembly for maintenance or repair. U.S. Pat. No. 3,572,159 describes a motion transmitting remote control assembly having this disadvantage.
Other disadvantages of the prior art cable assemblies is that the amount of force with which the ratchet teeth are urged together is not easily controlled. Furthermore, it is difficult to vary the force among identical configurations having different requirements.
A cable assembly for transmitting motion from one component to another requires that one end of the cable be attached to the first component at a predetermined position and that the second component be positioned correctly in relation to the position of the first component. The length of the cable that connects the components in the predetermined position should be set correctly within a fairly close tolerance so that the motion of one of the components is transmitted accurately by the cable to the second component. One feature of this method of assembly is that in the process of attaching the end of the cable assembly to the second component, a locking or latching member is moved to a locking position to set the correct length of the cable assembly concurrently with the making of the attachment to the second component.
SUMMARY OF THE INVENTION
The cable length adjusting device according to the present invention for coordinating the movement of components connected by the device includes a core wire adapted to be connected to a slider element having multiple engageable teeth that extend over a portion of the distance that separates the first and second components. A housing provides a hole through which the slider moves relative to a fixed attachment point along the axis of the cable. The housing can be connected to a mounting bracket or similar component that fixes its position against displacement toward either of the components connected by the cable assembly. A latch carried on the housing is moveable from a position of disengagement with the teeth of the slider to a position of locking engagement with the slider. A leaf spring carried on the housing supplies a force to the latch when in the locking position, which maintain spring assists the housing to the latch engaged with the teeth of the slider. In the unlocked position, the latch moves from engagement with the leaf spring. A compression spring fitted between the housing and the slider continuously applies a biasing force to the cable tending to move the cable and slider through the housing and away from one of the components connected by the cable assembly. Alternatively, a tension spring located on the opposite side of the housing from the location of the compression spring connects the housing and the slider. This spring applies to the slider and cable a force that continuously biases the cable away from one of the connected components. The tension spring or the compression spring takes up slack in the cable and eliminates the need for the operator to apply by hand a force to the cable assembly for this purpose.
This cable length adjuster, is adapted to be connected to the throttle lever of a carburetor by inserting a stud formed integrally with the housing into a hole in a grommet carried on the throttle lever mechanism of the carburetor. The latch, located on the housing adjacent the stud, is moved within a slot from the unlocked position to the locked position as the stud is inserted into the grommet. When the operator forces the stud into the grommet, the latch is forced, due to contact with the grommet, from the unlocked position to the locked position where it engages the slider teeth and fixes the slider to the housing. The housing is fixed in position against displacement by its attachment to the throttle lever mechanism of the carburetor. When this occurs, the correct length of the cable assembly is set automatically because its first end will have been connected to the throttle valve lever mechanism at the transmission, which is held in a predetermined position, preferably the wide open throttle position, and its housing is connected to the carburetor, whose throttle valve is held at the corresponding position when the housing connection is made to it.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the cable length adjuster according to this invention.
FIG. 2 is a partial side view in the direction 2--2 of the adjuster. of FIG. 1.
FIG. 3 is a partial side view in the direction 2--2 of the adjuster of FIG. 1 showing the cam moved into the self-locking position.
FIG. 4 is a cross section taken at plane 4--4 of FIG. 1.
FIG. 5 is a cross section taken at the plane 4--4 of FIG. 1 showing the cam in the locked position.
FIG. 6 shows the details of the latch tooth that engages the slider.
FIG. 7 is a bottom view of the latch tooth that engages the slots on the upper surface of the slider.
FIG. 8 is an isometric view of an alternate configuration of the cable length adjuster.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The cable length adjuster according to this invention is supported near one end on the throttle lever mechanism 12 of a carburetor. A stud 14 connected integrally with housing 16 is inserted into the hole of the grommet 18 mounted on the throttle lever mechanism. At the opposite end of the cable, at a substantial distance from the carburetor, the cable is connected to the throttle valve linkage of an automatic transmission.
A locking member 20 carried on the housing is fitted within a transversely directed slot so that it can move laterally with respect to the axis of the cable. The latch 20 is located on the housing adjacent stud 14 so that it contacts the flange of grommet 18 when the stud is inserted within the hole of the grommet. When the recess 22 is forced through the grommet into alignment with the mounting plane, locking member 20 is forced from the position of FIG. 1 across the axis of the cable to a position of locking engagement with the teeth 24 of a slider 26.
The compression spring 28 bears on the end face 30 of housing 16 and applies a force to a stop 32 fixed to the adjacent end of the slider. Cable 10 is connected mechanically to the opposite end of the slider; therefore, spring 28 applies a force that biases the slider and cable away from the transmission and toward the carburetor to remove slack in cable 10 and provide a precise adjustment. Engagement of latch 20 with slider teeth 24 connects the slider to the housing. Tang 34 prevents premature engagement of latch 20 before installation of the cable assembly to the throttle lever.
Slider 26 is rectangular in cross section and has on its upper surface, along a portion of its length, multiple transversely directed slots 24 that are engageable by locking member 20 as it moves from the unlocked position of FIGS. 2 and 4 to the locked position of FIGS. 3 and 5. In FIG. 4, housing 16 is shown to have a rectangular hole into which the slider 26 moves axially. Latch 20, guided within the transversely directed slot, includes a tang 34 on its upper surface, a transversely directed tooth on its lower surface, which is engageable with the teeth on the slider, and stops 38, 39, which limit transverse movement of the latch by contact with the side walls of housing 16.
A leaf spring 37 carried on the upper surface of the housing has three legs extending parallel to the axis of the slider. The outer legs 40, 42 are fitted respectively within axially directed slots 44, 46 on the upper surface of the housing and retain the leaf spring in its position on the housing by tangs 48, 50 which engage opposite axial ends of the upper surface of the housing. The outer legs are arcuate, as shown in FIGS. 2 and 3, and develop through contact with the lower surface of the recesses 44, 46 a downwardly directed force, which holds the leaf spring in contact with the lower edge of the recesses. Located laterally between the end fingers of the leaf spring is a center finger 52 directed parallel to the axis of the slider end located above latch 20. Finger 52 is held resiliently downward slightly above the upper surface of the latch and is contacted by tang 34 when it moves from the unlocked position of FIG. 4 to the locked position of FIG. 5. When the latch is moved to the locked position, finger 52 forces tooth 36 on the lower surface of latch 20 downward. Contact between the latch and the housing holds the latch engaged with slider 26, whose consecutive teeth 24 are engaged with tooth 36 on the lower surface of the latch.
In operation, the throttle valve linkage of the automatic transmission is located either at the wide open throttle position or the closed throttle position and the cable length adjuster assembly is connected to the throttle valve mechanism. Before the adjuster is connected, when it has the position corresponding to the position of the throttle valve linkage, the throttle plate of the carburetor is set at the position that corresponds to the position of the throttle valve linkage on the transmission. Then the adjuster stud 14 is forced into grommet 18 on the carburetor throttle valve mechanism. When this occurs, latch 20 is moved into locking engagement with the slider and the length of the cable is correctly set. The leaf spring assists holding the latch in the locked position between adjacent notches on the upper surface of the slider. The throttle valve linkage is part of a control used to regulate the hydraulic pressure of the transmission to control the automatic shift and timing between the shifts with reference to the position of the carburetor throttle plate.
Before the stud is inserted into the grommet, housing 16 is free to move relative to the slider. This movement permits location of the housing at the correct position on the slider before the initial insertion of the stud into the grommet. As the stud is inserted further within the grommet, latch 20 is moved from the position shown in FIGS. 2 and 4, where tang 34 is out of contact with leaf spring 52, to the position of FIGS. 3 and 5, where tang 34 is forced downwardly by contact with leaf spring finger 52 bringing the lower tooth 36 of the latch into engagement between adjacent successive teeth on the upper surface of slider 26. The compression spring 28 applies a tension force to the cable assembly and thereby removes unnecessary slack in the cable assembly.
In the cable length adjusting device of FIG. 8, a tension spring 60 is substituted for the compression spring 28. Spring 60 has one end connected to the housing 16' and its opposite end connected to a tubular extension 62 formed integrally with the slider 26'. The cable 64 extends entirely through a bore on a central axis of the slider and is connected to the slider by a staked ball 66 at the far end of the slider 26'. In the assembly of FIG. 8, latch 20' is located at the opposite axial side of stud 14 from its position shown in the assembly of FIG. 1. In some installations, this may be a more convenient position for the latch. Also, the central finger 52' of the leaf spring is directed toward the end of the slider and away from the transmission, whereas in the assembly of FIG. 1, the central finger is directed toward the transmission assembly. FIG. 8 shows the core wire 64 located in a conduit 72 that extends between the transmission throttle valve linkage and the cable length adjuster. The conduit may terminate near a mounting bracket 70 to protect the core wire from damage.
Tension spring 60 applies a biasing force to the core wire and slider and performs the same function as that of spring 28 in the design shown in FIG. 1. In some installations, it is preferred that the biasing spring be located on the interior side of the housing, where the tension spring is located, rather than on the exterior side of the housing, where the compression spring is located. In either case, the slider and core wire are urged by the spring away from the attachment at the transmission. | In a cable length adjuster, a slider is guided for movement within a housing and is biased by a spring to take up unnecessary slack in the cable. A latch is moveable, normal to the direction of slider movement, and becomes engaged with teeth on the slider. A stud carried on the housing fixes the position of the housing against movement in the direction the slider moves. A leaf spring forces the latch toward locking engagement with the slider. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/276,447, filed Sep. 14, 2009, the disclosure of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed generally to lighting devices, and more particularly to white light LED-based lighting devices with high luminous output configured for direct lumen-for-lumen replacement of existing incandescent lighting devices.
BACKGROUND
[0003] Energy conservation, in all its varied forms, has become a national priority of the United States as well as the rest of the world, from both the practical point of view of limited natural resources and recently as a security issue to reduce our dependence on foreign oil. A large proportion (some estimates are as high as one third) of the electricity used in residential homes in the United States each year goes to lighting. The percentage is much higher for businesses, street lights, amongst other varied items. Accordingly, there is an ongoing need to provide lighting, which is more energy efficient. It is well known that incandescent light bulbs are very energy inefficient light sources—about ninety percent of the electricity they consume is released as heat rather than light. This heat adds to the cooling load of a system during cooling season. In heating season the cost per BTU of heat that the lights give off is typically more expensive than the cost per BTU of the main heat source. The heat that is given off by the lighting also can cause “over shooting” of the desired temperature which waists energy and makes the space feel uncomfortable. Fluorescent light bulbs are more efficient than incandescent light bulbs (by a factor of about four) but are still quite inefficient as compared to solid state light emitters, such as light emitting diodes (LED's).
[0004] In addition, as compared to the normal lifetimes of solid state light emitters, incandescent light bulbs have relatively short lifetimes, i.e., typically in the range of 750 to 2000 hours. Fluorescent bulbs have longer lifetimes (e.g., 8,000 to 20,000 hours), but provide less favorable color reproduction and contain hazardous mercury. In dramatic comparison, the lifetime of light emitting diodes, for example, can generally be measured in decades (approximately 50,000 hrs or more).
[0005] One established method of comparing the output of different light generating sources has been coined color reproduction. Color reproduction is typically given numerical values using the so-called Color Rendering Index (CRI). CRI is a relative measurement of how the color rendition of an illumination system compares to that of a blackbody radiator, i.e., it is a relative measure of the shift in surface color of an object when lit by a particular lamp. The CRI equals 100 if a set of test colors being illuminated by an illumination system are the same as the results as being irradiated by a blackbody radiator. Daylight has the highest CRI (100), with incandescent bulbs being relatively close (about 95), and fluorescent lighting being less accurate (70 to 85). Certain types of specialized lighting devices have relatively low CRI's (e.g., mercury vapor or sodium, both as low as about 40 or even lower). Sodium lights are used, for example, to light highways and surface streets. Driver response time, however, significantly decreases with lower CRI values (for any given brightness, legibility decreases with lower CRI).
[0006] A practical issue faced by conventional lighting systems is the need to periodically replace the lighting devices (e.g., light bulbs, fixtures, ballasts, etc.). Such issues are particularly pronounced where access is difficult (e.g., vaulted ceilings, bridges, high buildings, traffic tunnels) and/or where change-out costs are extremely high. The typical lifetime of conventional fixtures is about 20 years, corresponding to a light-producing device usage of at least about 44,000 hours (based on a typical usage of 6 hours per day for 20 years). In contrast, light-producing device lifetimes are typically much shorter, thus creating the need for periodic change-outs. The potential number of residential homes that may be candidates for these periodic change-outs of the traditional incandescent lighting systems, including base fixtures and lamps themselves, may be extremely large and represent an attractive commercial enterprise. For example, in the United States alone new residential home construction has average approximately 1.5 million dwellings per year over the last 30 years running. Including older homes built before 1979, this represents at least 100 million residential dwellings that are candidates for potential upgrades to more energy efficient LED-based lighting systems.
[0007] Accordingly, for these and other reasons, efforts have been ongoing to develop ways by which solid state light emitters can be used in place of incandescent lights, fluorescent lights and other light-generating devices in a wide variety of applications. In addition, where solid state light emitters are already being used, efforts are ongoing to provide solid state light emitter-containing devices which have improved energy efficiency, color rendering index (CRI), contrast, and useful lifetime.
[0008] Light emitting diodes are well-known semiconductor devices that convert electrical current into light. A wide variety of light emitting diodes are used in increasingly diverse fields for an ever-expanding range of purposes. More specifically, light emitting diodes are semiconducting devices that emit light (ultraviolet, visible, or infrared) when an electrical potential difference is applied across a p-n junction structure. There are a number of well-known ways to make light emitting diodes and many associated structures, and the present invention can employ any such manufacturing technique.
[0009] The commonly recognized and commercially available light emitting diodes that are sold, for example, in electronics stores typically represents a “packaged” device made up of a number of parts. These packaged devices typically include a semiconductor-based light emitting diode and a means to encapsulate the light emitting diode. As is well known, a light emitting diode produces light by exciting electrons across the band gap between a conduction band and a valence band of a semiconductor active (light-emitting) layer. The electron transition generates light at a wavelength that depends on the band-gap energy difference. Thus, the color of the light (usually expressed in terms of its wavelength) emitted by a light emitting diode depends on the semiconductor materials embedded in the active layers of the light emitting diode.
[0010] Although the development of solid state light emitters, e.g., light emitting diodes, has in many ways revolutionized the lighting industry, some of the characteristics of solid state light emitters have presented challenges, some of which have not yet been fully met. For example, the emission spectrum of any particular light emitting diode is typically concentrated around a single wavelength (as dictated by the light emitting diode's composition and structure), which is desirable for some applications, but not desirable for others, e.g., for providing lighting, given that such an emission spectrum typically provides a very low CRI.
[0011] Because light that is perceived as white is necessarily a blend of light of two or more colors (or wavelengths), no single light emitting diode can produce white light. “White light” emitting devices have been produced which have a light emitting diode structure comprising individual red, green and blue light emitting diodes mounted on a common substrate. Other “white light” emitting devices have been produced which include a light emitting diode which generates blue light and a luminescent material (typically, a phosphor) that emits yellow light in response to excitation by the blue LED output, whereby the blue and the yellow light, when appropriately mixed, produce light that is perceived by the human eye as white light. A wide variety of luminescent materials are well-known and available to persons of skill in the art. For example, a phosphor is a luminescent material that emits a responsive radiation (typically visible light) when excited by a source of exciting radiation. In most instances, the responsive radiation has a wavelength, which is typically longer, than the wavelength of the exciting radiation. Other examples of luminescent materials include day glow tapes and inks, which glow in the visible spectrum upon illumination by ultraviolet light. Luminescent materials can be categorized as being down-converting, i.e., a material which converts photons to a lower energy level (longer wavelength) or up-converting, i.e., a material which converts photons to a higher energy level (shorter wavelength). Inclusion of luminescent materials in LED devices has typically been accomplished by adding the luminescent materials to a clear plastic encapsulating material (e.g., epoxy-based or silicone-based material).
[0012] As noted above, “white LED lights” (i.e., lights which are perceived as being white or near-white by the human eye) have been investigated as potential replacements for white light incandescent lamps. A representative example of a white LED light includes a package of a blue light emitting diode chip, made of gallium nitride (GaN), coated with a phosphor such as Yttrium Aluminum Garnet (YAG). In such an LED light, the blue light emitting diode chip produces a blue emission and the phosphor produces a yellow fluorescence on adsorbing that blue emission. For instance, in some designs, white light emitting diodes are fabricated by forming a ceramic phosphor layer on the output surface of a blue light-emitting semiconductor light emitting diode. Part of the blue rays emitted from the light emitting diode pass through the phosphor, while another part of the blue rays emitted from the light emitting diode chip are absorbed by the phosphor, which becomes excited and emits a yellow ray. The part of the blue light emitted by the light emitting diode, which is transmitted through the phosphor, is mixed with the yellow light generated by the phosphor. The human eye perceives the mixture of blue and yellow light as white light.
[0013] In another type of LED lamp, a light emitting diode chip that emits an ultraviolet ray which is absorbed by a phosphor material that produces red (R), green (G) and blue (B) light rays. In such an “RGB LED lamp”, the ultraviolet rays that have been radiated from the light emitting diode excites the phosphor, causing the phosphor to emit red, green and blue light rays which, when mixed, are perceived by the human eye as white light. Consequently, white light can also be obtained as a mixture of these light rays also.
[0014] Designs have been realized in which existing LED's and other electronics are assembled into an integrated housing fixture. In such designs, an LED or plurality of LED's are mounted on a circuit board encapsulated within the housing fixture, and a heat sink is typically mounted to the exterior surface of housing fixture to dissipate heat generated from within the device, the heat being generated by inefficient AC-to DC conversion from with the device. Although devices of this type can generate white light by any of the means described above, their external geometry typically does not permit direct functional replacement of existing incandescent lighting systems currently installed in residential homes. For example, one such prior art device is described in the CREE Lighting Fixtures Inc. catalog as part number LR6. The LR6 embodiment includes an encapsulated LED structure with an external heat sink assembly integrated as part of a thermal management system. The necessity of an external heat sink assembly in conjunction with an integrated thermal management system adds significant cost to the device as compared to equivalent light output off-the-shelf incandescent devices. In addition, the incorporation of the external heat sink assembly adds significant weight to the device as well as yields an overall external geometry to the lamp which is cylindrical in nature, not at all similar to the familiar incandescent lamps, which in itself may be an impediment to market acceptance to the average home owner envisioning a direct swap-out.
[0015] In addition to the above drawbacks, even more importantly, currently available LED-based lighting devices do not appear to generate sufficient light output, at a cost competitive price, to be a direct lumen-for-lumen replacement for incandescent lighting devices. This may be the single biggest reason for current poor market penetration of white-light LED lighting devices into the residential market place.
[0016] Given this, there is a need for a cost competitive LED-based white light device capable of direct lumen-for-lumen replacement of existing incandescent lighting devices which can be installed directly by the homeowner without the need of unwanted masonry work and without the additional cost of a licensed technician to perform such an installation.
SUMMARY OF THE INVENTION
[0017] Generally, the present invention is directed to lighting devices, and more particularly to white light LED-based lighting devices with high luminous output configured for direct lumen-for-lumen replacement of existing incandescent lighting devices.
[0018] One embodiment of the present invention describes a lighting device for generating diffuse white light comprising a group of solid state light emitters, electronics to activate the solid state light emitters by converting 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, the solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, the planar surface with solid state light emitters located at the entrance to the reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0019] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, a housing configured to supply a direct current (DC) voltage to the base of the lighting device, electronics to activate the solid state light emitters, wherein the electronics may be configured as a DC-to-DC converter to apply the appropriate DC voltage(s) and drive currents to the DC driven LEDs, the solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, the planar surface with solid state light emitters located at the entrance to the reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0020] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a group of solid state light emitters, said group including light emitting diodes energized by an alternating current (AC) drive voltage, a housing configured to supply a 120 volt AC (60 Hertz) input signal to the base of the lighting device, electronics to activate the solid state light emitters, wherein the electronics may be configured as a AC-to-AC converter to apply the appropriate AC voltage(s) and drive currents to the AC driven LEDs, the solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, the planar surface with solid state light emitters located at the entrance to the reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0021] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a first group of solid state light emitters, said first group including light emitting diodes energized by an alternating current (AC) drive voltage, a second group of solid state light emitters, said second group including light emitting diodes energized by a direct current (DC) drive voltage, a housing configured to supply a 120 volt AC (60 Hertz) input signal to the base of the lighting device, electronics to activate the solid state light emitters, wherein one channel of the electronics may be configured as a AC-to-AC converter to apply the appropriate AC voltage(s) and drive currents to the AC driven LEDs, a second channel of the electronics to activate the solid state light emitters, wherein said second channel of the electronics may be configured as a AC-to-DC converter to apply the appropriate DC voltage(s) and drive currents to the DC driven LEDs, the solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, the planar surface with solid state light emitters located at the entrance to the reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0022] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, electronics to activate the solid state light emitters, wherein the electronics converts 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, said solid state light emitters including a plurality of individual red, green, and blue light emitting diodes mounted on a common planar surface, reflective optics located at the output of the lighting device, said planar surface with solid state light emitters located at the entrance to said reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0023] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a first group of solid state light emitters, said first group including light emitting diodes energized by an direct current (DC) voltage with a color temperature in the range of 2800 to 3200 degrees Kelvin and a luminous flux greater than 650 lumens, a second group of solid state light emitters, said second group including light emitting diodes energized by a direct current (DC) voltage with a color temperature in the range of 5800 to 6200 degrees Kelvin and a luminous flux greater than 650 lumens, a housing configured to supply a 120 volt AC (60 Hertz) input signal to the base of the lighting device, a first set of electronics to activate the first group of solid state light emitters, wherein the first set of the electronics may be configured as an AC-to-DC converter to apply the appropriate DC voltage(s) and drive currents to said first group of DC driven LEDs, a second set of electronics to activate the second group of solid state light emitters, wherein the second set of the electronics may be configured as an AC-to-DC converter to apply the appropriate DC voltage(s) and drive currents to said second group of DC driven LEDs, said first and second group of solid state light emitters mounted on a common planar surface, reflective optics located at the output of the lighting device, said planar surface with solid state light emitters located at the entrance to said reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0024] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, electronics to activate the solid state light emitters, wherein the electronics converts 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, said solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, said reflective optics partially filled with a polymer material, said planar surface with solid state light emitters located at the entrance to said reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0025] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising, a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, electronics to activate the solid state light emitters, wherein the electronics converts 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, said solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, said planar surface with solid state light emitters located proximate to the focal plane of said reflective optics, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0026] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising, a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, electronics to activate the solid state light emitters, wherein the electronics converts 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, said group of solid state light emitters mounted on a concave surface, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0027] Another embodiment of the present invention describes a lighting device for generating diffuse white light comprising, a group of solid state light emitters, said group including light emitting diodes energized by a direct current (DC) voltage, electronics to activate the solid state light emitters, wherein the electronics converts 120 volt 60 cycles per second alternating current to a steady state direct current (DC) voltage, said group of solid state light emitters mounted on a convex surface, and an encapsulating housing enclosing the solid state light emitters and the activating electronics with a shape and form factor substantially equivalent to the American National Standards Institute (ANSI) PAR30, PAR 38, R20 or MR16 lighting device structure.
[0028] The above summary of the present invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures and the detailed description which follow more particularly exemplify these embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
[0030] FIG. 1 shows a schematic representation of one embodiment of the present invention depicting a white light LED device configured for direct replacement of existing incandescent devices categorized by the American National Standards Institute (ANSI) as having part number PAR30.
[0031] FIG. 1A shows a breakout of the components shown fully integrated in FIG. 1 .
[0032] FIG. 2 shows a schematic representation of the Light Emitting Diode (LED) array device.
[0033] FIG. 3 shows a schematic representation of a first outer horn-shaped reflector with an inner nested horn-shaped reflector with a shallower horn angle.
[0034] FIG. 3A shows a side view of the reflector depicted in FIG. 3 .
[0035] While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. 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.
DETAILED DESCRIPTION
[0036] In general, the present invention is directed to lighting devices, and more particularly to white light LED-based lighting devices with high luminous optical output configured for energy efficient lumen-for-lumen replacement of existing incandescent lighting devices. In the context of the present invention the phrase “energy efficient lumen-for-lumen replacement” refers to white light LED-based lighting devices which consume less electrical energy than the incandescent lighting devices they are intended to replace, while simultaneously producing at least the same, if not more, luminous optical output.
[0037] One embodiment of a white light LED device 10 in accordance with the present invention is depicted schematically in FIG. 1 . Incandescent light bulb devices with the shape depicted in FIG. 1 have generally been categorized by the American National Standards Institute (ANSI) as having part number PAR 30. A break out of the components that comprise the white light LED device 10 depicted in FIG. 1 , are shown in FIG. 1A , and it will be convenient to numerically label the components in the two figures consistently.
[0038] As shown in FIG. 1 , the dominant physical structure is the horn-shaped optical reflector 12 with diffusing element 14 attached thereto. The optical reflector 12 may be fabricated from a metal or metal-like material, polished on its' inner surface for high reflectivity, or a plastic material coated on its' inner surface with a metallic film yielding a high reflection co-efficient optimally approaching 90% or better. In one embodiment of the present invention, an LED array 16 (shown in FIG. 2 ) is located proximate to the entrance aperture 18 of the optical reflector 12 . Light emitting diodes typically have optical radiation that spans a viewing angle on the order of 120 degrees (+1-60 degrees from head-on to its' surface). Given this, it is important that the LED array 16 is located proximate to the entrance aperture 18 of the optical reflector 12 , and the diameter and horn angle Θ of the optical reflector 12 is sufficient to capture a large fraction of the light emanating from the LED array 16 .
[0039] One shortcoming of prior art LED lighting devices concerns “hot spots” or its counterpart “shadows” as an illumination device. In a preferred embodiment of the present invention, the geometrical relationship between the diameter of the LED array 16 (Φ LED ), the entrance aperture diameter and horn-angle Θ of the optical reflector 12 , and the spacing between the surface of the LED array 16 and the entrance aperture 18 of the optical reflector 12 are all simultaneously chosen to ensure that optical radiation emanating from the LEDs at angles greater than 30° reflect at least once off the inner surface of the optical reflector 12 . In this geometrical configuration, the optical reflector 12 behaves as an optical mixer to simultaneously smooth out what might other wise be hot spots and/or projected shadows. In addition to this, with a horn angle Θ on the order of 15 degrees, the optical reflector 12 may increase the projected light output in the far field (say, 10 to 15 feet from the white light LED device 10 ) by a factor 4 to 5× over the case with no reflector at all. This preferred embodiment satisfies the general requirements for both residential and commercial applications—sufficient optical energy delivered for illumination of objects over reasonable distances with no hot-spots or shadows.
[0040] With reference to FIG. 2 , the LED array 16 may be comprised of a plurality of individual discrete LEDs adhered to a common planar substrate material. The LEDs may be of a similar type, for example same color temperature and power consumption, or the LEDs may be a mixture of different color temperature and/or power levels to customize and/or modify the output characteristics of the white light LED device 10 . In one embodiment of the present invention, each discrete LED may be individually driven by a unique electrical activation signal (from the electrical driver board 22 ) or groups of LEDs may be “ganged” together and driven by a common electrical activation signal. In this configuration the following embodiments can be derived therefrom:
1) By utilizing a plurality of discrete LEDs of different color temperatures with individualized electrical activation signals, by varying the ratio of the electrical activation signals, the resultant color temperature at the output of the white light LED device 10 can be modified thereby by weighted “color mixing”. 2) By utilizing a plurality of discrete LEDs with individualized electrical activation signals, the luminous optical output of the white light LED device 10 can be modified by varying the fraction of activating available LEDs. For example, a traditional three-way lighting device could be enabled in this embodiment by external command to sequentially activate 25%, 50%, or 100% of the available LEDs. 3) The electrical driver board 22 may be configured to accept remote infrared commands to vary the activation levels to the individual LEDs. In this embodiment, both of the options defined above could be realized by a homeowner, for example, with a hand-held remote control device to either vary the color temperature or light output level of the white light LED device 10 .
[0044] Returning to FIG. 1 , for thermal management the LED array 16 may be in direct mechanical contact with heat sink assembly 20 . The heat sink assembly 20 may be a passive metal or metal-like like material or an active device such as a thermo-electric cooler, commonly referred to as a Peltier cooler. In the case of an active heat sink assembly 20 , the electrical power would be supplied by the electrical driver board 22 . The electrical driver board 22 is isolated from the external electrical connector 26 which screws into a standard light bulb socket by electrical insulating device 24 .
[0045] Heat sink assembly 20 may also include air vents or corrugate fins to increase the effective surface area to conduct or transfer outwardly heat generated from within the white light LED device 10 . Electrical driver board 22 may have individual electronic components which are designed to be energized by an alternating (AC) or direct current (DC) voltage. In one embodiment of the present invention, electrical driver board 22 may include the necessary electronic components to convert the standard 120 volt AC (60 Hertz) signal to a direct current (DC) voltage appropriate for direct current driven LED's mounted on LED array 16 .
[0046] Electrical driver board 22 may also include the appropriate electronic components to alter the luminous flux output of the LED's (commonly measured in units of lumens) and also modify the so-called color temperature of the white light LED device 10 . The color temperature, commonly stated in units of degrees Kelvin, is a measure of the peak wavelength of light emitted from a radiating body. It is commonplace in the light bulb industry to refer to incandescent white light devices that have a color temperature in the range of 2800 to 3200 degrees Kelvin as being a “warm” color, whereas compact fluorescent lighting devices which typically have a color temperature in the range of 5800 to 6200 degrees Kelvin are referred to as being a “cool” color.
[0047] Electrical driver board 22 may alter the color temperature of white light LED device 10 by varying the ratio of the steady state direct current (DC) voltages to the individual blue light emitting diodes. For example, to generate a more “warm” color in the range of 2800 to 3200 degrees Kelvin, the electronic components on circuit board 22 may be chosen to deliver slightly more current to the warm LEDs than to the cool LED's. Similarly, to generate a more “cool” color similar to a compact fluorescent bulb, the electronic components on circuit board 22 may be chosen to deliver slightly more current to the cool LEDs than to the warm LED. In one embodiment of the present invention, the electronic components on circuit board 22 may be configured to receive a remote command via a wireless RF link or equivalent means, to alter the current to individual blue LED's. Given this, both the luminous flux output (measured in Lumens) of the white light LED device 10 and the color temperature of the white light LED device 10 may be modified via remote control by varying the amplitude and ratio of the currents to the individual warm and cool blue LED's. Diffusing surface 14 may consist of a frosted glass, plastic, or opal like material such that the light emanating from diffusing surface 14 appears uniformly distributed over the surface with no apparent bright spots.
[0048] In another embodiment of the present invention, the LED devices mounted on circuit board 22 may be compatible with an alternating current (AC) drive voltage. In this configuration, circuit board 22 may be configured to accept a 120-volt AC (60 Hertz) input signal and convert that signal to an AC signal appropriate for the individual LEDs mounted thereon.
[0049] In another embodiment of the present invention, the LED devices mounted on the LED array 16 may be a mixture of some LEDs compatible with a direct current (DC) drive voltage and other LED devices designed to be driven by an alternating current (AC) drive voltage. In this configuration, circuit board 22 may be configured to supply both the appropriate AC and DC drive voltages to the respective AC and DC LED devices.
[0050] In an alternative embodiment of the present invention, the LED devices may be mounted on either a concave or convex surface and with (or without) the optical reflector 12 shown in FIG. 1 . By varying the shape of the LED array 16 surface from planar to either concave or convex, the overall angular distribution of light emanating from the white light LED device 10 can be varied accordingly. For example, by conceptually deforming the LED array 16 surface from planar to slightly concave may transform the light output to a narrower beam angle (i.e., transitioning the white light LED device 10 from a flood to more of a spot illuminator). Conversely, by conceptually deforming the LED array 16 surface from planar to slightly convex, may transform the light output to a wider beam angle. Taken to one extreme, the convex LED array 16 surface may be a hemispherical shape with a light output that spans 180 degrees or more (in this configuration, it may be advantageous that the white light LED device 10 has no reflector at all).
[0051] In yet another embodiment of the present invention, the optical reflector 12 shown in FIG. 1 may be partially or wholly filled with a polymer material. In this embodiment, the polymer material may be in direct physical contact, and/or chemically bonded to the LEDs and function as a moisture and water barrier thereto. The polymer may also function as a diffusing agent, but in all cases it is desirable that the polymer material be partially transparent at visible wavelengths. Candidate polymer materials may include acrylic polymers or copolymers including polymethyl methacrylate.
[0052] The polymer material may also have a fluorescent or phosphorescent material dispersed throughout. In this configuration, it may be possible to alter the light output color.
[0053] The present invention should not be considered limited to the particular examples described above, but rather should be understood to cover all aspects of the invention as fairly set out in the attached claims. Various modifications to the shape and form factors described above, equivalent processes to supplying the appropriate drive voltages to the LEDs, as well as numerous structures to which the present invention may be applicable will be readily apparent to those of skill in the art to which the present invention is directed upon review of the present specification. The following claims are intended to cover such modifications and devices. | A white light LED-based lighting device configured for direct replacement of existing incandescent lighting devices is provided. The white light LED-based lighting device comprises a group of solid state light emitting diodes, electronics to activate the light emitting diodes, said solid state light emitters mounted on a planar surface, reflective optics located at the output of the lighting device, the planar surface with solid state light emitters located at the entrance to said reflective optics, and an encapsulating housing configured for direct replacement of existing incandescent lighting devices. | 5 |
BACKGROUND
[0001] The present invention relates to solar concentrator systems and, more particularly, to an alignment and collection system for a solar concentrator system.
[0002] Solar power systems fall generally into two categories: fixed position flat panel systems, and tracking solar collection systems. Fixed position flat panel systems employ one or more stationary panels that are arranged in an area having an unobstructed view of the sun. As the earth rotates, the sun's rays move over the stationary panel(s) with varying degrees of intensity depending upon geographic location, the time of day and the time of the year. In contrast, tracking solar collection systems collect, and focus the sun's rays onto one or more solar panels. Tracking solar collectors employ a tracking system that follows the sun's path in order to enhance energy collection. Simply put, fixed position flat panels represent a passive solar collection system, while tracking solar concentrator systems represent a more active energy collection system.
[0003] Tracking systems for solar collectors take on a variety of forms, from complex computer and satellite (GPS) tracking to the use of photodiodes. GPS tracking relies on determining a particular location on the ground, and correlating that location to the location of the sun at a given, known, time of day. More conventional systems utilize an auxiliary alignment sensor that employs photodiodes. The photodiodes rely on differential sensing parameters to track the sun. That is, one or more photodiode cells are exposed to the sun's rays. The sun's rays impinge upon the photodiodes and a controller determines how much, for example, voltage is produced by each photodiode cell. The controller then orients the plurality of photodiode cells until voltage from each cell is substantially similar. At this point, an offset is calculated and a solar collector is oriented to a desired orientation. The offset represents a distance between a solar collector and the photodiodes. The need to calculate an offset increases tracking complexity and reduces collection efficiency.
SUMMARY
[0004] According to one embodiment of the present invention, a solar concentration system includes at least two solar energy receivers having a central focal point, with each of the at least two solar energy receivers generating an energy output based on received light energy. An actuation system is operatively coupled to the at least two solar energy receivers. The actuation system is configured and disposed to shift the at least two solar energy receivers along at least one axis. A control system is operatively linked to the at least two solar receivers and the actuation system. The control system senses the energy output of each of the at least two solar energy receivers and shifts the actuation system along the at least one axis causing solar energy to be directed at the central focal point. When the solar energy is directed at the central focal point, the energy output of each of the at least two solar energy receivers is substantially identical.
[0005] A method and system for aligning solar receivers with the sun is also described and claimed herein.
[0006] Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0008] FIG. 1 is a schematic diagram of a solar energy alignment and collection system including a plurality of solar receivers having a central focal point in accordance with an exemplary embodiment, illustrating with solar energy impinging upon the solar receivers at a position spaced from the focal point;
[0009] FIG. 2 is a schematic diagram of the solar energy alignment and collection system in accordance with an exemplary embodiment illustrating the solar alignment system shifting the solar receivers to position the solar energy at a focal point of the solar receivers;
[0010] FIG. 3 is a schematic diagram of the solar energy alignment and collection system in accordance with an exemplary embodiment illustrating the solar receivers shifted to a position that aligns the solar energy at the focal point; and
[0011] FIG. 4 is a block diagram of a general-purpose computer linked to a solar concentrator alignment system in accordance with an exemplary embodiment.
DETAILED DESCRIPTION
[0012] With reference now to FIG. 1 , a solar energy alignment and concentration system constructed in accordance with an exemplary embodiment is indicated generally at 2 . Solar energy alignment and collection system 2 includes a base member 4 , upon which are mounted a plurality of solar energy receivers 6 - 9 arranged in an array. In accordance with an exemplary embodiment, solar energy alignment and collection system 2 includes four (4) solar energy receivers, however the number of receivers could vary without departing from the scope of the invention. In further accordance with an exemplary embodiment, solar receivers 6 - 9 take the form of triple junction solar cells, such as photovoltaic cells, arranged in a quadrant pattern. Solar energy alignment and collection system 2 further includes an actuation system 20 having first and second actuators 24 and 25 operatively coupled to the array of solar receivers 6 - 9 . First and second actuators 24 and 25 take the form of electro-mechanical systems configured to shift each actuator 24 , 25 along corresponding ones of first and second perpendicular axes. Of course it should be understood that actuators 24 and 25 could take on a variety of forms such as electric motor and gear assemblies, hydraulic actuators and/or piezo-electric elements. Further shown in FIG. 1 , solar energy alignment and collection system 2 includes an alignment controller 40 having an analog-to-digital (A-D) converter 42 that operates as a computer, and a digital-to-analog (D-A) converter 44 . Finally, solar energy alignment and collection system 2 includes an energy storage system 50 which, as will be discussed more fully below, receives and stores electrical energy that is converted from light energy received by solar energy receivers 6 - 9 .
[0013] Alignment controller 40 is operatively connected to each of the plurality of solar receivers 6 - 9 via signal lines 60 - 63 respectively. Alignment controller 40 is also electrically coupled to each actuator 24 , 25 via corresponding control lines 65 and 66 . With this arrangement, controller 40 determines an optimum position of solar receivers 6 - 9 relative to the sun to ensure optimal alignment of solar energy alignment and collection system 2 . More specifically, alignment controller 40 ensures that radiation intensity from the sun focuses on a centroid of the array of solar receivers 6 - 9 . Towards that end, alignment controller 40 monitors energy output from each of solar receiver 6 - 9 .
[0014] The energy output from each solar receiver is evaluated to determine whether any one of the plurality of solar receivers 6 - 9 is outputting more energy than others of the solar receivers 6 - 9 . In accordance with one aspect of an exemplary embodiment, a current sensing device employing a Hall effect sensor is employed to provide an electrically isolated voltage output that is proportional to current flow. The Hall effect sensor has a very low resistance and, as such, does not interfere with the current flow from solar receivers 6 - 9 . That is, in the event that solar energy is focused on, for example, solar receiver 6 such as shown in FIG. 1 , energy output from solar receiver 6 will be higher than the energy output from solar receivers 7 - 9 . Alignment controller 40 evaluates the deviation of the energy output from each cell and then selectively activates actuator 24 and/or 25 to shift the array of solar receivers 6 - 9 and re-align the solar radiation intensity with the centroid to achieve a balanced energy output. In order to start balancing energy output, alignment controller 40 activates actuators 24 and 25 to shift base member 4 along corresponding first and second axes to centralize the solar energy impinging upon solar receivers 6 - 9 such as shown in FIG. 2 . As base member 4 transitions, alignment controller 40 continues to monitor the energy output from each solar receiver 6 - 9 . Alignment controller 40 continues to determine and compare the energy output from each solar receiver 6 - 9 until the solar energy focuses on a centroid (not separately labeled) of solar receivers 6 - 9 such as shown in FIG. 3 . When the solar energy focuses on the centroid of solar receivers 6 - 9 , energy output from each solar receiver 6 - 9 is substantially identical. A portion of the energy output may be stored to aid in powering a tracking system when solar receivers 6 - 9 are not fully positioned and producing power. Exemplary storage devices could include batteries and flywheel storage devices.
[0015] With this arrangement, the exemplary embodiments provide a system that accurately aligns solar receiving cells with solar energy from the sun in order to enhance energy production. In particular, when employing concentrated solar energy collection systems, precise alignment of the solar energy collectors with the solar rays enhances energy collection. Moreover, by combining solar energy tracking or alignment features with the same solar cells/receivers used for energy production, there is no need for an auxiliary sensor to compute alignment. In this manner, exemplary embodiments reduce overall system cost and eliminate the need to calculate offsets or other factors that contribute to alignment error.
[0016] The method of aligning solar energy receivers with the sun described herein can also be practiced with a general-purpose computer such as illustrated at 400 in FIG. 4 and the method may be coded as a set of instructions on removable or hard media for use by the general-purpose computer 400 . In FIG. 4 , computer system 400 has at least one microprocessor or central processing unit (CPU) 405 . CPU 405 is interconnected via a system bus 410 to a random access memory (RAM) 415 , a read-only memory (ROM) 420 , an input/output (I/O) adapter 425 for connecting a removable data and/or program storage device 430 , a mass data and/or program storage device 435 , a user interface adapter 440 for connecting a keyboard 445 and a mouse 450 , a port adapter 455 for connecting a data port 460 , a display adapter 465 for connecting a display device 470 , and alignment system 40 that is configured and disposed to shift first and second actuators to align solar receivers 6 - 9 with solar rays from the sun.
[0017] ROM 420 contains the basic operating system for computer system 400 . The operating system may alternatively reside in RAM 415 or elsewhere as is known in the art. Examples of removable data and/or program storage device 430 include magnetic media such as floppy drives and tape drives and optical media such as CD ROM drives. Examples of mass data and/or program storage device 435 include hard disk drives and non-volatile memory such as flash memory. In addition to keyboard 445 and mouse 450 , other user input devices such as trackballs, writing tablets, pressure pads, microphones, light pens and position-sensing screen displays may be connected to user interface 440 . Examples of display devices include cathode-ray tubes (CRT) and liquid crystal displays (LCD).
[0018] A computer program with an appropriate application interface may be created by one of skill in the art and stored on the system or a data and/or program storage device to simplify the practicing of this invention. In operation, information for or the computer program created to run the present invention is loaded on the appropriate removable data and/or program storage device 430 , fed through data port 460 or typed in using keyboard 445 .
[0019] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one ore more other features, integers, steps, operations, element components, and/or groups thereof.
[0020] The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated
[0021] While preferred embodiments have been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described. | A solar energy alignment and collection system includes at least two solar energy receivers having a central focal point, with each of the at least two solar energy receivers generating an energy output. An actuation system is operatively coupled to the at least two solar energy receivers and is configured and disposed to shift the solar energy receivers along at least one axis. A control system, operatively linked to the solar receivers and the actuation system, senses the energy output of each solar energy receiver and shifts the actuation system along the at least one axis causing solar energy to be directed at the central focal point. When solar energy is directed at the central focal point, the energy output of each solar energy receiver is substantially identical. | 7 |
BACKGROUND AND SUMMARY OF THE INVENTION
[0001] Exemplary embodiments of the present invention relate to a connecting arrangement for connecting a wiper blade to a wiper arm for a windscreen wiper system of a vehicle. The connecting arrangement comprises a connecting element designed for holding the wiper blade, which can be fitted onto the wiper arm in an installation direction which runs transversely with respect to a wiping surface definable by the wiping movement of the wiper blade. At least one securing element of the connecting arrangement serves for the positionally secured holding of the connecting element on the wiper arm. Furthermore, exemplary embodiments of the present invention relate to a method for connecting a wiper blade to a wiper arm of a windscreen wiper system of a vehicle.
[0002] German patent document DE 691 01 340 T2 describes an articulated connection between a wiper arm and a wiper blade. In the wiper arm, which has a U-profile in cross section, an opening is provided to receive a latch that can be displaced along the wiper arm. If the latch is displaced away from the free end of the wiper arm, in other words backwards, a slot provided on the latch releases an articulation axle that joins two longitudinal walls of a chuck together. The chuck is pushed here into an opening which is made in a main bracket of the wiper blade, wherein clamps formed on the chuck latch into recesses made on the main bracket.
[0003] German patent document DE 101 30 903 A1 describes a wiper arm of a windscreen wiper system for a vehicle, the end region of which has a U-profile in cross section that is open downwards. An adaptor that holds a wiper blade can be inserted from below into the end region of the wiper arm, that is to say in an installation direction running perpendicularly with respect to a wiping surface definable by the wiping movement of the wiper blade. The side walls of the adaptor have recesses whose internal dimensions correspond to the external dimensions of projections protruding in a lateral and inward direction from limbs of the wiper arm. When the adaptor is inserted into the end region of the wiper arm in the installation direction, the projections therefore move along the recesses. To lock the adaptor in respect of the wiper arm, the adaptor is displaced together with the wiper blade towards an open end of the wiper arm and the projections on the wiper arm extend into latching recesses provided on the adaptor. A latching tongue arranged on the adaptor is inserted into a recess arranged on the wiper arm in this positionally secured position of the adaptor and thereby indicates that the adaptor has reached its operational position.
[0004] German patent document DE 10 2008 011 449 A1 likewise describes a connection of a wiper blade to a wiper arm by means of an adaptor on the wiper blade, which adaptor is inserted from below into an end region of the wiper arm. The adaptor is then displaced together with the wiper blade laterally towards one end of the wiper arm in order to lock the adaptor in respect of the wiper arm and therefore bring the adaptor into a functional position.
[0005] The fact that securing the adaptor in its position with respect to the wiper arm requires cumbersome handling of the adaptor is to be regarded as a disadvantage of these kinds of connecting arrangements.
[0006] German patent document DE 10 2005 016 485 A1 describes a device for connecting a wiper blade to a wiper arm of a windscreen wiper system in an articulated fashion. An end region of the wiper arm is designed as a downwardly open, cuboid hollow body having two projections protruding inwardly from its side walls. An adaptor for holding a wiper blade has two latching tongues that latch with the two projections when the adaptor is pushed into the hollow body on the wiper arm from below. A further projection formed on a side wall of the hollow body and projecting inwardly engages in a depression that is made in the adaptor. In this way, the adaptor is held positionally secured in the end region of the wiper arm.
[0007] This kind of connecting arrangement is comparatively complex and it is also difficult to remove the adaptor and with it the wiper blade from the wiper arm.
[0008] Exemplary embodiments of the present invention provide a connecting arrangement of the kind specified at the beginning and a corresponding method enabling particularly simple and functionally reliable connection of a wiper blade to a wiper arm of a windscreen wiper system.
[0009] The connecting arrangement according to the invention for connecting a wiper blade to a wiper arm of a windscreen wiper system of a vehicle comprises a connecting element designed for holding the wiper blade. The connecting element can be fitted onto the wiper arm in an installation direction running transversely with respect to a wiping surface definable by the wiping movement of the wiper blade. A securing element of the connecting arrangement, which serves for the positionally secured holding of the connecting element on the wiper arm, is designed as a slider arranged on the wiper arm and having a U-profile in cross section, which can be displaced along the wiper arm from an installation position into a functional position securing the connecting element. A particularly simple and functionally reliable connection of the wiper blade to the wiper arm is achieved here by the connecting element not having to be displaced together with the wiper blade from the installation position into the functional position in order to fix the wiper blade on the wiper arm. Instead, the connecting element remains in its installation position, while only the slider is displaced along the wiper arm in order to secure the connecting element from working loose from the wiper arm. This makes it far easier to handle the wiper blade when fitting it onto or removing it from the wiper arm.
[0010] The slider has a back and two limbs, wherein at least one projection engaging around the wiper arm on the lower side is arranged on the limbs of the slider. A slider of this kind provides impact protection if the wiper arm without a wiper blade fitted to it strikes the windscreen, for example due to an oversight by a mechanic after removing the wiper blade from the wiper arm. Impact protection of this kind is particularly effective if the wiper arm is made of metal and the slider is made of a flexible material such as plastic. The slider, which engages around the wiper arm on the lower side, also ensures particularly good guidance of the slider along the wiper arm.
[0011] A wiper blade having the connecting element is fitted onto the wiper arm particularly easily and intuitively here by a mechanic, ensuring a particularly high degree of reliability against incorrect fitting. To remove the wiper blade, the slider merely needs to be moved from the functional position securing the connecting element into the installation position, and then the connecting element and with it the wiper blade can be removed from the wiper arm counter to the installation direction.
[0012] As a pressing force, which presses the wiper blade against the windscreen, is applied to the wiper arm when the wiper blade is on the windscreen of the vehicle, the wiper arm can also reliably move the wiper blade over the windscreen if the slider is in the installation position rather than in the functional position. This applies even if the slider is defective so that it does not secure the connecting element as desired even in the functional position.
[0013] The connecting arrangement described here can also be produced with a comparatively small connecting element. This is advantageous in that only a small amount of water is released by the connecting element onto the windscreen of the vehicle with a connecting element that requires little structural space, even if it is raining or washer fluid is hitting the windscreen.
[0014] In an advantageous embodiment of the invention, one end region of the slider extends beyond an end region of the wiper arm in the installation position. As a result, a mechanic can very easily tell whether the slider is in the installation position or in the functional position securing the connecting element.
[0015] It is also advantageous if the wiper arm has at least one latching notch that is engaged with a latching nose arranged on the slider in the functional position and/or in the installation position of the slider. This is because the latching of the latching nose in the latching notch is both visibly noticeable and can be heard and felt. In this way, the mechanic can be informed that the slider is in the functional position or in the installation position. It is particularly favorable if one and the same latching nose is in engagement with a first latching notch in the functional position and with a second latching notch in the installation position. Alternatively, however, only one latching notch may also be provided, which is assigned to one of the two positions. The wiper arm can also have the latching nose and the slider the latching notches.
[0016] In a further advantageous embodiment of the invention, the wiper arm has a U-profile in cross section at least in the region of the connecting element, wherein in a back of the wiper arm is arranged a through-opening in which a corresponding projection of the connecting element is received in the installation position. If the projection, the external dimensions of which correspond to the internal dimensions of the through-opening, is received in the through-opening, then it is ensured that the connecting element and with it the wiper blade cannot move either in the direction of the longitudinal extent of the wiper arm or transversely with respect to this direction of longitudinal extent. In other words, the connecting element and with it the wiper blade are secured and fixed in their position in the plane of the wiping surface by such an adjustment of the projection and of the through-opening corresponding to it. The mechanic can also tell, when the projection is passed through the through-opening, that the connecting element is in the correct installation position in which the slider can be displaced into the functional position securing the connecting element.
[0017] If the projection and the through-opening are other than round in shape, for example if the projection and the through-opening are designed to be oval or angular, in particular rectangular or square, then the connecting element can also be secured against rotation in respect of the wiper arm by bringing the projection into engagement in the through-opening.
[0018] At least a part region of the projection preferably has a contour that is the same as a contour of a recess provided on the slider, wherein at least the part region of the projection abuts with the recess in the functional position of the slider. In this way, by bringing the slider into abutment with the part region of the projection, it is possibly to visually determine whether the slider has reached the functional position. This is because this is not the case if there is still a gap between the contour delimiting the recess on the slider and the contour of the part region of the projection.
[0019] It has proven to be even more advantageous if the through-opening and the projection corresponding to it are specifically designed for a respective place at which the wiper arm is affixed to the vehicle. For example, the geometry of the through-opening and of the projection for a driver-side wiper arm and the associated wiper blade may differ from the geometry for a passenger-side wiper arm and the associated wiper blade. A respectively specific geometry of the through-opening and of the projection may also be provided for a wiper arm for a right-hand-drive vehicle or a left-hand-drive vehicle in order to ensure that only the actually associated wiper blade can be fitted to the wiper arm provided for it. Such protection against mix-ups can also be provided in order to be able to distinguish the wiper arm and the wiper blade of a rear windscreen wiper from a wiper arm and the wiper blade of a front windscreen wiper.
[0020] It is also advantageous if the slider comprises a front wall by means of which an open end region of the wiper arm can be closed at least in part in the functional position. The slider therefore protects the connecting element received in the end region of the wiper arm and, at the same time, provide a visually attractive end of the end region of the wiper arm. The front wall closing the wiper arm to the front, that is to say in the direction of the longitudinal extent thereof, also protects the windscreen to a particularly great extent if the wiper arm having no wiper blade accidentally strikes it.
[0021] In order to achieve particularly secure fixing of the connecting element on the wiper arm in the installation position, provision can be made, according to a further advantageous embodiment of the invention, for the wiper arm to have at least one recess open in the installation direction which is designed to receive a corresponding projection formed on the connecting element.
[0022] It has proven to be even more advantageous if the connecting element comprises a lower part holding the wiper blade and an upper part fixed to the wiper arm in the functional position, wherein the lower part is held relative to the upper part so that it can move on the latter. As a result, the wiper blade can be adjusted to the course of the windscreen surface when the windscreen, which is usually spherically curved, is being wiped. Because the parts that allow relative movement between wiper arm and wiper blade and are susceptible to wear are parts of the connecting element, these are likewise replaced when replacing the wiper blade together with the connecting element. This ensures that the relative movement between wiper blade and wiper arm remains smooth.
[0023] The upper part is preferably designed as a rocker rotatably supported on a pin or bearing bolt that is passed through a passage opening in the lower part. Such bearing of the upper part on the lower part ensures particularly smooth relative movement between wiper arm and wiper blade.
[0024] At least one stop formed on the lower part preferably limits the relative movement of the upper part in respect of the lower part. This is because stops can be used to limit the relative movement of the wiper blade in respect of the wiper arm particularly easily to the small degree required.
[0025] If the wiper arm, according to a further advantageous embodiment of the invention, is in abutment with side walls of the upper part in the functional position, this likewise ensures a fixing of the connecting element on the wiper arm that is particularly secure, in particular secure against rotation.
[0026] Finally, it has proven advantageous if the slider and/or the wiper arm have a recess designed to receive a component of the wiper blade if the wiper blade moves relative to the wiper arm. As a result, the slider and the wiper arm can be closed to a particularly large extent in a visually and acoustically advantageous manner, and the relative movement of the wiper blade in respect of the wiper arm is nevertheless possible as a result of the recesses.
[0027] In the method according to the invention for connecting a wiper blade to a wiper arm of a windscreen wiper system of a vehicle, a connecting element designed for holding the wiper blade is fitted onto the wiper arm in an installation direction running transversely with respect to a wiping surface definable by the wiping movement of the wiper blade. By means of at least one securing element, the connecting element is held positionally secured on the wiper arm. In this case, as a securing element, a slider arranged on the wiper arm and having a U-profile in cross section is displaced along the wiper arm from an installation position into a functional position securing the connecting element.
[0028] The advantages and preferred embodiments described in respect of the connecting arrangement according to the invention also apply to the method according to the invention.
[0029] The features and combinations of features specified in the description above and the features and combinations of features specified in the description of the figures and/or in the figures only below can be used not only in the combination specified in each case, but also in other combinations or on their own without falling outside the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0030] Further advantages, features and details of the invention can be seen in the claims, the following description of preferred embodiments and by reference to the drawings. The following can be seen in the drawings:
[0031] FIG. 1 illustrates a part of a wiper arm of a windscreen wiper system of a vehicle with a wiper blade fixed to the wiper arm, wherein a sliding latch fixes an adaptor holding the wiper blade;
[0032] FIG. 2 illustrates the wiper blade according to FIG. 1 with the adaptor comprising a rocker and a rider;
[0033] FIG. 3 illustrates the wiper arm and the sliding latch removed from the wiper arm in a perspective view;
[0034] FIG. 4 illustrates the sliding latch viewed from below;
[0035] FIG. 5 illustrates an exploded representation of components of the adaptor;
[0036] FIG. 6 illustrates a view from below of the rocker of the adaptor received in an end region of the wiper arm, which is secured in its position by the sliding latch displaced into its functional position;
[0037] FIG. 7 illustrates the wiper arm with its sliding latch displaced forward into a removal position in which the adaptor can be removed from the end region of the wiper arm by pulling downwards;
[0038] FIG. 8 illustrates a view from below of the end region of the wiper arm with the rocker received therein, wherein the sliding latch is displaced in to the removal position shown in FIG. 7 ;
[0039] FIG. 9 illustrates the adaptor removed downwards from the end region of the wiper arm and holding the wiper blade, and the wiper arm with the sliding latch in its removal position;
[0040] FIG. 10 illustrates a side view of the wiper arm with the wiper blade held on it; and
[0041] FIG. 11 illustrates an alternative design of a wiper arm with a wiper blade arranged thereon, which is held by a wiper-arm-specific adaptor.
DETAILED DESCRIPTION
[0042] FIG. 1 shows part of a wiper arm 12 and a wiper blade 14 of a windscreen wiper system 10 of a vehicle. Of an adaptor 26 (cf. FIG. 2 ) that is received in an end region of the wiper arm 12 designed as a receiving region, FIG. 1 shows only a lower part designed as a rider 16 , which engages around spring strips 18 of the wiper blade 14 and therefore holds the wiper blade 14 . The wiper blade 14 also comprises a spoiler 20 and a blade rubber (not shown in FIG. 1 ) to wipe a windscreen (also not shown) of the vehicle.
[0043] In order to hold the adaptor 26 securely on the wiper arm 12 , a sliding latch 22 is arranged on the wiper arm 12 , which is held thereon such that it can be displaced in a direction of the longitudinal extent of the wiper arm 12 . An arrow symbol 24 applied to the sliding latch 22 in the form of a double arrow shows the directions in which the sliding latch 22 can be displaced in respect of the wiper arm 12 .
[0044] In a functional position of the sliding latch 22 shown in FIG. 1 , the latter ensures that the adaptor 26 (cf. FIG. 2 ) and with it the wiper blade 14 cannot be removed from the wiper arm 12 . In this functional position of the sliding latch 22 , a recess 28 provided in the sliding latch 22 and having a semi-circular contour is in abutment with a cylindrical part region 30 of a projection 32 protruding upwards over a base body of a rocker 34 of the adaptor 26 (cf. FIG. 2 ).
[0045] FIG. 2 shows the rocker 34 which is designed as an upper part of the multipart adaptor 26 , without the sliding latch 22 concealing the rocker 34 . The rocker 34 is supported on a pin-shaped bearing bolt 36 which is pushed through a passage opening 38 provided in the rider 16 (cf. FIG. 5 ). Ribs can be provided in the passage opening 38 in order to fix the bearing bolt 36 so that it cannot rotate therein (cf. FIG. 5 ).
[0046] If the wiper blade 14 is to be received in the end region 40 of the wiper arm 12 by means of the adaptor 26 holding the wiper blade 14 , it is inserted from below into the end region 40 of the wiper arm 12 which is open downwards (cf. FIG. 9 ). For this purpose, the sliding latch 22 is first displaced into an installation position shown in FIG. 9 and allowing the adaptor 26 to be fitted, which is likewise a removal position allowing the adaptor 26 to be removed.
[0047] As can be seen in FIG. 3 , the end region 40 of the wiper arm 12 has a U-profile in cross section which comprises a back 42 and two limbs 44 extending downwards from the back 42 . The limbs 44 each have two downwardly open recesses 46 which, if the adaptor 26 is brought into the end region 40 , receive two bar studs 48 that extend beyond respective side walls 50 of the rocker 34 (cf. FIG. 2 ).
[0048] If the four bar studs 48 are received in the four recesses 46 corresponding to them in the two limbs 44 of the end region 40 of the wiper arm 12 , the adaptor 26 can no longer move in the direction of the longitudinal extent of the wiper arm 12 . The projection 32 of the rocker 34 then also passes through a through-opening 52 in the back 42 of the wiper arm 12 . A further recess 86 in the back 42 of the wiper arm 12 serves to receive an elevation 88 of the rider 16 that the latter has in the region of the passage opening 38 (cf. FIG. 3 and FIG. 5 ).
[0049] If the adaptor 26 is inserted into the end region 40 of the wiper arm 12 , the side walls 50 of the rocker 34 are in abutment with the inner sides of the limbs 44 . As a result, the adaptor 26 is also fixed to the wiper arm 12 in a direction transversely with respect to the direction of extent of the wiper arm 12 , in other words transversely with respect to the direction of longitudinal extent of the wiper blade 14 .
[0050] Furthermore, the sliding latch 22 also ensures that the adaptor 26 cannot move out of the receiving region 40 of the wiper arm 12 upwards, in other words perpendicularly with respect to the wiping surface definable by the wiping movement of the wiper blade 14 .
[0051] For this purpose, as shown in particular in FIG. 4 , two rails 56 are arranged on respective side walls 54 of the sliding latch 22 likewise having a U-profile in cross section, these rails 56 projecting inwardly from an inner side of the respective side wall 54 . These rails 56 engage around the wiper arm 12 in the end region 40 on the lower side and therefore serve, in cooperation with a back 58 connecting the side walls 54 of the sliding latch 22 (cf. FIG. 3 ) as a guide for the translational displacement of the sliding latch 22 relative to the wiper arm 12 .
[0052] The bar studs 48 received in the recesses 46 of the wiper arm 12 also rest on the rails 56 of the sliding latch 22 if the latter is displaced into its functional position shown in FIG. 1 , in other words in this case backwards.
[0053] A region 60 between the two rails 56 and a region 62 between the rear rail 56 and a latching nose 64 likewise projecting inwardly from the side wall 54 make it possible, when the sliding latch 22 is displaced into the installation position, to bring the bar studs 48 of the rocker 34 into the recesses 46 provided in the side walls 44 of the wiper arm 12 by inserting the adaptor 26 from below into the end region 40 of the wiper arm 12 .
[0054] The latching noses 64 projecting inwardly from the side walls 54 of the sliding latch 22 can be inserted into front latching notches 66 or into rear latching notches 68 that are made in the two limbs 44 of the wiper arm 12 in the end region 40 thereof. If the respective latching nose 64 is in the front latching notch 66 , then the sliding latch 22 protrudes forward over the end region 40 of the wiper arm 12 and a front wall 70 of the sliding latch 22 is spaced apart from an end 72 of the wiper arm 12 (cf. FIG. 3 , FIG. 4 and FIG. 8 ).
[0055] If, on the other hand, the sliding latch 22 is displaced backwards, the latching nose 64 is then in the rear latching notch 68 (cf. FIG. 6 ), so the front wall 70 of the sliding latch 22 is in abutment with the front end 72 of the wiper arm 12 . A mechanic working on the sliding latch 22 can clearly hear and feel, in other words haptically determine, whether the latching nose 64 is latched in the front latching notch 66 or in the rear latching notch 68 .
[0056] A further, visual indication that the installation position of the sliding latch 22 allowing the adaptor 26 to be fitted or removed from the end region 40 of the wiper arm 12 has been reached is given by the position of the part region 30 . The part region 30 , which emerges over the through-opening 52 in the back 42 of the wiper arm 12 , is in abutment with the recess 28 provided in the sliding latch 22 if the latching nose 64 is in the rear latching notch 68 (cf. FIG. 1 and FIG. 6 ).
[0057] If, on the other hand, the sliding latch 22 is pulled forward, then the latching nose 64 is in the front latching notch 66 (cf. FIG. 8 ). The rear latching notch 68 is then free here and there is a space between the part region 30 of the projection 32 and the recess 28 in the back 58 of the sliding latch 22 (cf. FIG. 7 ).
[0058] FIG. 6 shows the sliding latch 22 , which holds the rocker 34 , displaced into its functional position in that the bar studs 48 arranged on the side walls 50 of the rocker 34 rest on the laterally inwardly projecting rails 56 of the sliding latch 22 . In the functional position, the latching nose 64 formed on the sliding latch 22 is in engagement with the rear latching notch 68 in the limb 44 of the wiper arm 12 . The front latching notch 66 , on the other hand, is free.
[0059] In contrast, in the installation position or removal position of the sliding latch 22 shown in FIG. 7 , the latter is displaced forward and the rear latching notch 68 is free while the latching nose 64 is inserted into the front latching notch 66 . The cylindrical part region 30 of the projection 32 of the rocker 34 is spaced apart from the semi-circular recess 28 in the back 58 of the sliding latch 22 .
[0060] The cylindrical part region 30 can, as shown by way of example in this case, to aid clarity, have an emblem 74 , for example a trade mark emblem, that stands out in the form of a relief, or such an emblem 74 can be made to stand out here in some other way, for example through use of a different colour. In order to ensure that the sliding latch 22 is particularly easy to operate when it is being displaced with respect to the wiper arm 12 , the limbs 54 of the sliding latch 22 have a ribbing 76 here.
[0061] FIG. 8 shows the sliding latch 22 releasing the rocker 34 , in other words the sliding latch 22 displaced forward into the installation position or removal position (cf. FIG. 7 ) in a perspective view from below. The direction of displacement forwards is shown by an arrow 77 . In the removal position, the bar studs 48 are level with the regions 60 , 62 , so they are no longer resting on the rails 56 . The latching nose 64 is latched into the front latching notch 66 . The latching of the latching nose 64 in the front latching notch 66 as a result of the forward displacement can be clearly heard and felt by the mechanic.
[0062] Then, as shown in FIG. 9 , the adaptor 26 holding the wiper blade 14 by means of the rider 16 can be removed from the end region 40 of the wiper arm 12 downwards, in other words perpendicularly with respect to the wiping surface definable by the wiping movement of the wiper blade 14 .
[0063] The installation direction and the removal direction are shown by a movement arrow 78 in FIG. 9 . When being fitted, the adaptor 26 and with it the wiper blade 14 are moved upwards and, when being removed to change a wiper blade 14 that has to be replaced, they are correspondingly moved downwards.
[0064] FIG. 10 shows the wiper arm 12 holding the wiper blade 14 in a side view, wherein the wiper blade 14 is tilted relative to the wiper arm 12 , that is to say as a result of the tilting of the rider 16 relative to the rocker 34 resting on the wiper arm 12 . This side view shows that one of the limbs 44 of the wiper arm 12 has a recess 80 that allows an upwards movement of the spoiler 20 caused by the tilting of the wiper blade 14 .
[0065] Two stops 82 formed on each side of the rider 16 and bevelled to respective outer sides of the rider 16 (cf. FIG. 5 ) limit the relative movement of the rider 16 in respect of the rocker 34 . The tilting of the wiper blade 14 in the direction opposite the direction shown in FIG. 10 causes the spoiler 20 to move upwards in its region arranged in front of the rider 16 . In the process, a recess that is in the form of a notch 84 and is arranged in the front wall 70 of the sliding latch 22 ensures that the spoiler 20 can move upwards (cf. FIG. 11 ).
[0066] Finally, FIG. 11 shows, by way of example, how incorrect fitting is avoided in this case through the geometric arrangement of the projection 32 of the rocker 34 and the recess 52 corresponding to this projection 32 in the back 42 of the wiper arm 12 . For example, for a passenger-side wiper arm 12 and the wiper blade 14 associated with it, a specific design of the projection 32 corresponding to the place at which the wiper arm 12 is affixed and of the recess 52 corresponding to it can be provided.
[0067] In the design of the wiper arm 12 and of the rocker 34 shown in FIG. 11 , the recess 52 is not rectangular (as is the case, for example, with the design of the projection 32 and recess 52 in FIG. 9 ), but the projection 32 is instead rectangular in its rear region and semi-circular in its front region. Accordingly, the recess 52 corresponding to this partially semi-circular projection 32 in the back 42 of the wiper arm 12 is likewise semi-circular in the front region and angular in the rear region. In alternative embodiments, different designs of projection 32 and recess 52 can ensure against mix-ups.
[0068] The connecting arrangement shown here for connecting the wiper blade 14 to the wiper arm 12 is possible both using designs of the wiper arm 12 in which the latter is formed as a simple rod arm, and using wiper arms 12 in which the latter has a more robust design, for example a different shape in the end region 40 and in the rear region of the wiper arm 12 adjoining the end region 40 respectively.
[0069] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. | A connecting arrangement for connecting a wiper blade to a wiper arm for a windscreen wiper system of a vehicle. An adaptor for holding the wiper blade is fitted onto the wiper arm in an installation direction running transversely with respect to a wiping surface definable by the wiping movement of the wiper blade. The connecting arrangement includes a securing element designed as a sliding latch arranged on the wiper arm. The sliding latch, which has a U-profile in cross section, serves for the positionally secured holding of the adaptor on the wiper arm, and the sliding latch is displaceable along the wiper arm from an installation position into a functional position securing the adaptor. The sliding latch has a back and two limbs, and at least one projection engaging around the wiper arm on the lower side is arranged on the limbs of the sliding latch. | 8 |
FIELD OF THE INVENTION
The invention relates to a base spacer that is useful for securing a horizontal member to a vertical member in a desired vertical and horizontal position.
BACKGROUND OF THE INVENTION
Electrical switch pole units must be secured to support members with sufficient force to provide a secure arrangement that permits careful alignment of the supported member to the support. In the case of an electrical telephone or power pole, the horizontal support beam must securely hold the electrical switching components that vertically extend therefrom.
One example of a clamping arrangement for power poles is shown in U.S. Pat. No. 4,909,463, the disclosure of which is herein incorporated by reference. The clamp of this patent includes a pole unit base and a dead-end bracket secured around a horizontal support member by a single U-bolt. Deformable “tangs” are used in the connection to provide a securing force when tightened about the horizontal support member.
It would be desirable to have a support system that was useful for securing a vertically extending member to a horizontal support.
SUMMARY OF THE INVENTION
The invention relates to a base spacer plate that is useful for securing a vertically extending first member to a horizontally extending second member, wherein the spacer has an extended horizontal surface and at least one deformable finger extending vertically from the horizontal surface. The horizontal surface also has: (a) a pair of oval openings dimensioned to receive and locate securing bolts, and (b) a channel along one edge of said spacer that exhibits a length sufficient to align opposite legs of U-bolts used to secure the vertical and horizontal members, wherein said deformable finger extends from said horizontal surface at less than a right angle.
The spacer plate of the invention is useful for providing accurate vertical and horizontal alignment for vertical members mounted to a horizontal bearing surface as well as prevent movement of the vertical member relative to the horizontal member when uneven side force is applied to either end of the vertical member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a frontal view of a spacer plate of the invention.
FIG. 2 is a side illustration of the spacer plate from FIG. 1 .
FIGS. 3-5 show the spacer plate as used for securing a vertical member to a horizontal support.
FIGS. 6-9 illustrate the use of a base spacer according to the invention to secure a horizontal member to a vertical member.
FIG. 10 is a view of a spacer according to the invention in use for securing an overhead high voltage phase switch to a horizontal support member.
FIGS. 11 and 12 are views of the spacer of FIG. 10 for securing an overhead high voltage phase switch to a horizontal support member.
DETAILED DESCRIPTION
The invention is conveniently described with reference to the enclosed figures.
FIG. 1 is a top view of base spacer 1 . FIG. 2 is a side view. Please note that the terms “horizontal” and “vertical” are used solely as directional frame of reference. In use, the spacer plate can be installed in virtually any planar orientation without affecting its function or performance. The following description will relate to a spacer plate standing vertically as it would be used for securing a vertical beam member against a horizontal support member.
Base spacer 1 has a substantially flat vertical plate surface 2 with a pair of fingers 3 that extend horizontally from plate surface 2 at an angle 4 that is less than a right angle, i.e., 90° and at an angle sufficient to contact the outer surface of a horizontal member 5 when secured by base spacer 1 with bolts 6 against a vertical support member 7 . (See FIGS. 3-5.) Preferably, angle 4 is within the range from about 45° to 85°. Even more preferably, angle 4 is at an angle within the range of 60° to 80° relative to plate surface 2 .
After a distance 8 , vertical fingers 3 are bent away from plate surface 2 at an angle 9 that is sufficient to increase the amount of force needed to bend finger 3 over distance 8 away from plate surface 2 as spacer 1 is tightened against horizontal member 5 . Angle 9 increases relative to a perpendicular plane from plate surface 2 at bend 32 . Fingers 3 extend from the surface of plate 10 for a total distance 41 and increases the length of distance 8 .
In the embodiment depicted, spacer plate 2 has a top edge 18 and a bottom edge 19 . Channel 11 on top edge 18 is located between a pair of fingers 3 with a width 15 that can vary depending on the amount of urging force desired on the surface of vertical member 7 that will be secured by plate 1 . Channel 11 has interior edges 12 , 13 extending towards the center of plate 11 for a distance 14 .
Elongated bolt holes 15 are located on plate 1 opposite channel 11 toward bottom edge 19 and are spaced on centers separated by distance 16 . The centers of bolt holes 15 are spaced from bottom edge 19 by a distance 20 .
Bolt holes 15 are also spaced on center from lateral edges 22 of plate 1 by a distance 23 on center with a diameter sufficient to allow outer edges 21 of holes 15 to be spaced from lateral edge 22 by a distance 24 and aligned with interior edges 12 , 13 (as shown by the dotted line). With such dimensions, a pair of U-bolts 6 will fit through holes 15 as well as against interior edges 12 , 13 of fingers 3 .
Space plate 1 may come in a variety of physical dimensions to secure a variety of sized members against horizontal movement. To that end, plate 1 may have a length 28 between the bottom edge 27 at bend 8 on fingers 3 and bottom edge 29 of elongated bolt holes 15 .
Vertical member 7 is secured in position with spacer plate 1 by passing one leg of each U-bolt 6 through elongated bolt hole 15 . The other leg of U-bolt 6 is passed into channel 11 between fingers 3 . The male end of each U-bolt 6 is then passed through a hole 30 in vertical member 7 and secured thereto with nut 31 .
The dimensions of plate 1 should be sufficient so that bottom edge 27 at bend 8 contacts the upper surface 32 of horizontal member 5 . As nuts 31 are tightened, spacer 1 pulls down on the mating surface of horizontal member 5 and pulls the edge of slots 29 tight against U-bolts 6 . The spacer secures the U-bolts in position and structurally secure U-bolts 6 to horizontal member 5 as bearing members.
FIGS. 6-9 illustrate the steps used to secure vertical member 7 to horizontal member 5 using U-bolts 6 , spacer plate 1 , and nuts 31 . As shown by FIGS. 6-9, U-bolts 6 are loosely placed around horizontal member 5 . Spacer 1 is then positioned over the upright legs of U-bolts 6 so that vertical fingers 3 engage lateral side surface 50 on horizontal member 5 . Angle 4 and length 8 to bend 27 cause spacer 1 to rest at an angle 51 relative to the upper surface 52 of horizontal member 5 . Vertical member 7 is then placed over U-bolts 6 and secured with nuts 31 . As nuts 31 are tightened, angle 51 is reduced until vertical member 7 is flat against spacer 1 against upper surface 52 . Pressure from the angular deformation of vertical fingers 3 against side surface 50 maintains a secure connection of vertical member 7 to horizontal member 5 .
Additionally, bolt holes 15 and interior edges 12 , 13 of channel 11 secure against torsional movement of vertical member 7 . This torsional resistance can be particularly useful when, as shown in FIG. 10, spacer 1 is used to secure an overhead high voltage power line distribution phase switch 60 against torsional rotation when rigid rod 61 rotates switch 60 to disconnect power flow through the switch. See, copending application Ser. No. 09/457,593 (attorney docket no. 39343) filed concurrently herewith and whose disclosure is incorporated herein by reference.
FIGS. 10-12 show spacer 1 in position when securing a horizontal member 5 , such as crossarm 70 on a telephone pole, to a vertical member 7 , such as channel-shaped support 71 for a high voltage interrupter switch 60 an overhead power distribution system. | A base spacer that is useful for securing a horizontal member to a vertical support with accurate vertical and horizontal position has an extended horizontal surface and at least one deformable finger extending vertically from this horizontal surface. The horizontal surface also has: (a) a pair of oval openings dimensioned to receive securing bolts, wherein the deformable finger extends from the horizontal surface at less that a right angle for a distance sufficient to contact a horizontal member secured by the spacer. | 5 |
[0001] This application is related to a co-pending application that bears Motorola docket number CR97-133 and U.S. Ser. No. 09/144,686, entitled “MAGNETIC RANDOM ACCESS MEMORY AND FABRICATING METHOD THEREOF,” filed on Aug. 31, 1998, assigned to the same assignee and incorporated herein by this reference, co-pending application that bears Motorola docket number CR 97 - 158 and U.S. Ser. No. 08/986,764, entitled “PROCESS OF PATTERNING MAGNETIC FILMS” filed on Dec. 8, 1997, assigned to the same assignee and incorporated herein by this reference and issued U.S. Pat. No. 5,768,181, entitled “MAGNETIC DEVICE HAVING MULTI-LAYER WITH INSULATING AND CONDUCTIVE LAYERS”, issued Jun. 16, 1998, assigned to the same assignee and incorporated herein by.
FIELD OF THE INVENTION
[0002] The present invention relates to magnetic elements for information storage and/or sensing and a fabricating method thereof, and more particularly, to a device and method of fabricating the magnetic element to include insulative veils.
BACKGROUND OF THE INVENTION
[0003] Typically, a magnetic element, such as a magnetic memory element, has a structure that includes ferromagnetic layers separated by a non-magnetic layer. Information is stored as directions of magnetization vectors in magnetic layers. Magnetic vectors in one magnetic layer, for instance, are magnetically fixed or pinned, while the magnetization direction of the other magnetic layer is free to switch between the same and opposite directions that are called “parallel” and “anti-parallel” states, respectively. In response to parallel and anti-parallel states, the magnetic memory element represents two different resistances. The resistance has minimum and maximum values when the magnetization vectors of the two magnetic layers point in substantially the same and opposite directions, respectively. Accordingly, a detection of change in resistance allows a device, such as an MRAM device, to provide information stored in the magnetic memory element. The difference between the minimum and maximum resistance values, divided by the minimum resistance is known as the magnetoresistance ratio (MR).
[0004] An MRAM device integrates magnetic elements, more particularly magnetic memory elements, and other circuits, for example, a control circuit for magnetic memory elements, comparators for detecting states in a magnetic memory element, input/output circuits, etc. These circuits are fabricated in the process of CMOS (complementary metal-oxide semiconductor) technology in order to lower the power consumption of the device.
[0005] During typical magnetic element fabrication, such as MRAM element fabrication, metal films are grown by sputter deposition, evaporation, or epitaxy techniques. One such magnetic element structure includes a substrate, a base electrode multilayer stack, a synthetic antiferromagnetic (SAF) structure, an insulating tunnel barrier layer, and a top electrode stack. The base electrode layer stack is formed on the substrate and includes a first seed layer deposited on the substrate, a template layer formed on the seed layer, a layer of an antiferromagnetic material on the template layer and a pinned ferromagnetic layer formed on and exchange coupled with the underlying antiferromagnetic layer. The ferromagnetic layer is called the pinned layer because its magnetic moment (magnetization direction) is prevented from rotation in the presence of an applied magnetic field. The SAF structure includes a pinned ferromagnetic layer, and a fixed ferromagnetic layer, separated by a layer of ruthenium, or the like. The top electrode stack includes a free ferromagnetic layer and a protective layer formed on the free layer. The magnetic moment of the free ferromagnetic layer is not pinned by exchange coupling, and is thus free to rotate in the presence of applied magnetic fields.
[0006] During fabrication of these magnetic elements, ion milling is commonly used for the dry etching of the magnetic materials. However, during the process of dry etching, conducting veils are left remaining on the sides of the magnetic tunnel junction (MTJ). These remaining veils lead to electrical shorting of the device between the bottom and top electrodes, more particularly across the insulating tunnel barrier. Currently, wet etching techniques are used in the semiconductor industry to etch away the veils, but are not amenable for use in conjunction with magnetic materials due to their chemical attack on the magnetic materials leading to device performance degradation.
[0007] To avoid the shorting problem caused by veils, the current etching process is done in two steps. First the top magnetic layer of the magnetic element is etched or defined, then the whole stack is etched using a dry etch technique; or vice versa.
[0008] Veils may be minimized by varying the etching beam angle relative to the wafer surface. Since the edges of the top and bottom magnetic layers do not overlap, the veils do not cause a shorting problem between the top and bottom magnetic layers. However, this is a very complex etching process. Stopping the etch of the top magnetic layer without over-etching through the ultra thin tunnel barrier, and into the bottom magnetic layer is very difficult to do. Over-etching into the bottom magnetic layer will cause unwanted magnetic poles shifting the resistance-magnetic field response of the magnetic element. This technique also limits the free magnetic layer to be placed on top of the tunnel barrier.
[0009] Accordingly, it is a purpose of the present invention to provide for a magnetic element having formed as a part thereof, insulating veils, which no longer include conductive or magnetic properties.
[0010] It is a still further purpose of the present invention to provide a method of forming a magnetic element with insulating veils.
[0011] It is another purpose of the present invention to provide a method of fabricating a magnetic element that includes plasma oxygen ashing of the magnetic stack to transform conducting veils into insulating veils.
[0012] It is another purpose of the present invention to provide a method of forming a magnetic element with insulating veils which is amenable to simple and high throughput manufacturing.
[0013] It is still a further purpose of the present invention to provide a method of forming a magnetic element with insulating veils that allows for the formation of the free magnetic layer anywhere within the magnetic element stack.
SUMMARY OF THE INVENTION
[0014] These needs and others are substantially met through provision of a magnetic element including a base metal layer, a first electrode, a second electrode and a spacer layer. The base metal layer is positioned on an uppermost surface of a substrate element. A spacer layer is located between the ferromagnetic layers for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers. In an alternative embodiment, the structure is described as including a SAF structure to allow for proper balancing of magnetostatic interaction in the magnetic element. The device includes insulative veils characterized as electrically isolating the first electrode and the second electrode, the insulative veils including non-magnetic and insulating dielectric properties. Additionally disclosed is a method of fabricating the magnetic element with insulative veils that have been transformed from having conductive properties to having insulative properties through oxygen plasma ashing techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIGS. 1 - 3 illustrate in cross-sectional views, the steps in fabricating a magnetic element with insulative veils according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] During the course of this description, like numbers are used to identify like elements according to the different figures that illustrate the invention. FIGS. 1 - 3 illustrate in cross-sectional views a magnetic element according to the present invention. More particularly, illustrated in FIG. 1, is a first step in the fabrication of a patterned magnetic element 10 . Illustrated in FIG. 1, is a fully patterned magnetic element structure 10 . The structure includes a substrate 12 , a first electrode multilayer stack 14 , a spacer layer 16 including oxidized aluminum, and a second electrode multilayer stack 18 . It should be understood that spacer layer 16 is formed dependent upon the type of magnetic element being fabricated. More particularly, in a MTJ structure, spacer layer 16 is formed of a dielectric material, and in a spin valve structure, spacer layer 16 is formed of a conductive material. First electrode multilayer stack 14 and second electrode multilayer stack 18 include ferromagnetic layers. First electrode layers 14 are formed on a base metal layer 13 , which is formed on substrate 12 . Base metal layer 13 is disclosed as composed of a single metal material or layer or a stack of more than one metal material or layer. First electrode layer 14 includes a first seed layer 20 , deposited on base metal layer 13 , a template layer 22 , a layer of antiferromagnetic pinning material 24 , and a fixed ferromagnetic layer 26 formed on and exchange coupled with the underlying antiferromagnetic pinning layer 24 . It should be understood that anticipated by this disclosure is a pseudo spin-valve structure that would not include the antiferromagnetic pinning layer. In this instance, the pseudo spin-valve structure would include a first electrode and a second electrode including a first switching field and a second switching field thereby defining the pseudo spin-valve structure.
[0017] Typically, seed layer 20 is formed of tantalum nitride (TaNx) having template layer 22 formed thereon. Template layer 22 in this particular embodiment is formed of ruthenium (Ru). Pinning layer 24 is typically formed of iridium manganese (IrMn).
[0018] In this particular embodiment, ferromagnetic layer 26 is described as fixed, or pinned, in that its magnetic moment is prevented from rotation in the presence of an applied magnetic field. Ferromagnetic layer 26 is typically formed of alloys of one or more of the following: nickel (Ni), iron (Fe), and cobalt (Co).
[0019] Second electrode stack 18 includes a free ferromagnetic layer 28 and a protective contact layer 30 . The magnetic moment of the free ferromagnetic layer 28 is not fixed, or pinned, by exchange coupling, and is free to rotate in the presence of an applied magnetic field. Free ferromagnetic layer 28 is typically formed of a nickel iron (NiFe) alloy or a nickel iron cobalt (NiFeCo) alloy. It should be understood that a reversed, or flipped, structure is anticipated by this disclosure. More particularly, it is anticipated that the disclosed magnetic element can be formed to include a top fixed, or pinned layer, and thus described as a top pinned structure. In addition, a device including dual spacer layers is anticipated by this structure. In this instance, magnetic element 10 would structurally include a bottom pinned magnetic layer, a bottom spacer, or tunnel barrier layer, a free magnetic layer, a top spacer, or tunnel barrier layer, and a top pinned magnetic layer. The bottom pinned magnetic layer, the free magnetic layer and the top pinned magnetic layer include ferromagnetic layers. The bottom magnetic layer is optionally formed on a diffusion barrier layer which is formed on a metal lead which in turn is typically formed on some type of dielectric materal. The diffusion barrier layer is typically formed of tantalum nitride (TaN), and aids in the thermal stability of the magnetic element.
[0020] Fixed ferromagnetic layer 26 is described as pinned, or fixed, in that its magnetic moment is prevented from rotation in the presence of an applied magnetic field. Ferromagnetic layer 26 as previously stated is typically formed of alloys of one or more of the following: nickel (Ni), iron (Fe), and cobalt (Co). Magnetic layer 28 is described as a free ferromagnetic layer. Accordingly, the magnetic moment of free ferromagnetic layer 28 is not fixed, or pinned, by exchange coupling, and is free to rotate in the presence of an applied magnetic field. Free ferromagnetic layer 28 is formed co-linear with fixed magnetic layer 26 and of alloys of one or more of the following: nickel (Ni), iron (Fe), and cobalt (Co). Fixed ferromagnetic layer 26 is described as having a thickness within a range of 5-500Å. Free ferromagnetic layer 28 is described as having a thickness generally in the range of 5-500Å.
[0021] In this particular embodiment, spacer layer 16 is formed of aluminum (Al) and oxygen (O). More particularly, spacer layer 16 is formed having a general formula of AlO x , where 0<x≦1.5. It should be understood that when device 10 includes dual spacer layers, as previously discussed, that the second spacer layer would be formed of oxidized tantalum (Ta), generally having the formula TaO x , where 0<x≦2.5.
[0022] Illustrated in FIG. 2, the next step in the method of fabricating device 10 according to the present invention. More particularly, as illustrated, the plurality of epitaxially deposited layers are etched to define device 10 having included as a part thereof conductive veils 32 . Conductive veils 32 are formed subsequent to ion milling or reactive ion etching which is utilized to form device 10 . Conductive veils 32 provide an electrical path between first electrode 14 and second electrode 18 and thereby cause device 10 to fail, due to the shorting out of the device across insulative spacer layer 16 . Typically these veils are etched off utilizing a wet etch process, which causes degraded device performance, and thus not suitable for MRAM device fabrication. In addition, wet etching away conductive veils 32 is hard to utilize for deep submicron features, results in a non-uniform lateral over-etch, causing switching fields to vary, and results in an inability to make every cell the same shape and having the same switching field.
[0023] Referring now to FIG. 3, illustrated is the next step in the method of fabricating device 10 according to the present invention. More particularly, as illustrated, conductive veils 32 are next dry etched, using oxygen plasma ashing at either room temperature, more particularly at temperature of 150° C., or a higher temperature. This oxygen plasma etching of conductive veils 32 provides for the transformation of conductive veils 32 into insulative veils 34 . Insulative veils 34 are thus described as inactive having non-magnetic, dielectric properties. The fabrication of insulative veils 32 results in a device having electrically isolated, first electrode 14 and second electrode 18 .
[0024] It should be understood that due to the ability to electrically isolate first electrode 14 and second electrode 18 , that free magnetic layer 28 can be formed anywhere in device 10 . Prior art dictates the fabrication of the free magnetic layer on the top of the device stack due to its fabrication as a thin layer, and the ability to turn portions of it into a dielectric material, thus electrically isolating the electrodes. This transformation of the thin free magnetic layer as disclosed and claimed herein provides for the blocking of the conduction path through the naturally formed conductive veil between the first electrode and the second electrode. In this particular invention, in that the conductive veils have been transformed into insulative veils 34 , free magnetic layer 28 can be formed anywhere in the device stack. It should be understood that it is anticipated by this disclosure that device 10 may include a synthetic antiferromagnetic (SAF) structure that is formed between two tunnel barrier, or spacer, layers, or alternatively below a first spacer or tunnel barrier layer, or on a surface of a top spacer or tunnel barrier layer.
[0025] Thus, a magnetic element with insulative veils and fabricating method thereof is disclosed in which the device structure and method of fabricating the device is improved based on the transformation of conductive veils to insulative veils. As disclosed, this technique can be applied to devices using patterned magnetic elements, such as magnetic sensors, magnetic recording heads, magnetic recording media, or the like. Accordingly, such instances are intended to be covered by this disclosure | An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element ( 10 ) including a first electrode ( 14 ), a second electrode ( 18 ) and a spacer layer ( 16 ). The first electrode ( 14 ) and the second electrode ( 18 ) include ferromagnetic layers ( 26 & 28 ). A spacer layer ( 16 ) is located between the ferromagnetic layer ( 26 ) of the first electrode ( 14 ) and the ferromagnetic layer ( 28 ) of the second electrode ( 16 ) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers ( 26 & 28 ). The device includes insulative veils ( 34 ) characterized as electrically isolating the first electrode ( 14 ) and the second electrode ( 18 ), the insulative veils ( 34 ) including non-magnetic and insulating dielectric properties. Additionally disclosed is a method of fabricating the magnetic element ( 10 ) with insulative veils ( 34 ) that have been transformed from having conductive properties to insulative properties through oxygen plasma ashing techniques. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of provisional patent application Ser. No. 60/511,527 filed on Oct. 15, 2003, which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a siding panel for an exterior wall of a building. In particular, the invention provides for a drainage plane positioned on the rear face of a contoured foam backer used with siding products. The drainage plane allows water to more efficiently dissipate from the exterior wall.
BACKGROUND OF THE INVENTION
[0003] The construction industry, both new construction and remodeling, is increasingly confronted with problems associated with the buildup of moisture on surfaces within exterior walls. This moisture buildup may cause various types of mold, including black mold. Such mold is frequently blamed for causing serious respiratory illnesses and numerous other health conditions in both humans and animals. Individuals often go to great expense to remove mold from their homes, and in extreme cases walls and even entire structures are torn down.
[0004] Building codes have long required that exterior walls be permeable so that moisture can escape if such moisture finds its way into the wall. However, on occasion due to poor insulation, inadequate flashing, leaking pipes or bad building practices, water can nonetheless find its way into exterior walls. In some cases water can be found in such large quantities that it overwhelms the exterior wall system. In other words, the exterior wall material simply cannot dissipate the moisture fast enough before conditions become sufficient to promote the growth of mold.
[0005] A need has arisen to improve dissipation of water in the exterior walls of buildings.
SUMMARY OF THE INVENTION
[0006] The present invention is intended to augment exterior wall systems to assist in the removal of water or water vapor from such exterior walls. Exterior walls often include insulation products, for example, contoured foam backing or composite siding. Exterior insulation includes a rear face that contacts the building. The present invention provides a drainage plane on that rear face to facilitate the removal of water from the exterior wall. The drainage plane can be made up of a grid of grooves that provide a path for water to flow. These grooves encourage water from leaks and water from heavy condensation to run theredown off the exterior wall and away from the building. In the preferred embodiment, and when used with composite siding, the water flows out through weep holes located in the bottom of the siding. It is understood that the grooves may be positioned in any number of ways, including vertically or diagonally.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
[0008] FIG. 1 is a front perspective view of a composite siding panel including the drainage plane of the present invention;
[0009] FIG. 2 is a rear exploded perspective view of a panel backing and siding product including the drainage plane of the present invention;
[0010] FIG. 3A is a rear plan view of the backing of FIG. 2 ;
[0011] FIG. 3B is a rear plan view of the backing showing the drainage plane arranged in a diagonal pattern;
[0012] FIG. 3C is a rear plan view of the backing showing the drainage plane arranged in a vertical pattern;
[0013] FIG. 3D is a rear plan view of the backing showing the drainage plane arranged in a square pattern; and
[0014] FIG. 4 is a cross sectional view illustrating a preferred groove profile.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The present invention relates to a drainage arrangement positioned on a rear face of an exterior insulation product. The construction market utilizes a large number of exterior insulation products. The preferred embodiment of the instant application is described in the context of composite siding by example only. It is understood that the instant invention could be applied to any exterior insulation product having a planar surface.
[0016] The drainage arrangement, as it is positioned on the otherwise flat rear face of a foam backer, is generally referred to as a drainage plane. The drainage plane is configured to encourage water from leaks and water from heavy condensation to run down grooves positioned therein. The grooves can be of any of a wide variety of configurations and can be laid out in any of a wide variety of patterns. The grooves can be positioned in a grid and can be positioned anywhere from vertically to some angle off the vertical. The drainage plane of the present invention is particularly beneficial in those cases where a foam board is positioned flat against another component such as an OSB panel that would naturally resist the water from freely running down the back of the OSB panel.
[0017] With reference to the drawings wherein like items are numbered alike, and with particular reference to FIGS. 1, 2 , and 3 A, a composite siding product 10 is illustrated. The composite siding product 10 can include a panel backing 14 that can be operably attachable or mountable to a siding component 12 . By way of example and not limitation, the siding component 12 can be a contoured siding product 12 and/or the panel backing 14 can be a contoured foam backer. It is understood that the backing 14 can be attached to the siding component 12 in a wide variety of fashions, where attaching and mounting are general terms that can include, by way of example and not limitation, an adhesive, chemical bonding, interlocking complementary surfaces, fasteners, and/or “dropping in” the backing 14 at the job site. As seen in FIG. 4 , the rear face of the backing 14 can be positioned parallel to and proximate to an exterior wall 18 of a building. Returning to FIGS. 1, 2 , and 3 A, the siding component 12 can include a nail strip 15 that can include at least one nail aperture 15 ′, a locking flange 17 , and/or a locking lip 17 ′. The locking flange 17 can be located at a top edge of the siding 12 and the locking lip 17 ′ can be located at a bottom edge of the siding component 12 . The locking flange 17 can be configured to operably engage the locking lip 17 ′ of an adjacent contour siding 12 . In this way, the composite siding panels 10 can be vertically interlocked in courses up the exterior wall 18 of the building. Installers can drive nails through nail apertures 15 ′ to secure each piece onto the exterior wall 18 .
[0018] By way of example and not limitation, the backing 14 can be formed of an expanded polystyrene (EPS) foam material, and the siding component 12 can be formed of a vinyl material. By way of example and not limitation, the foam can have a permeability rating of 1.0 or higher. By way of example and not limitation, a suitable adhesively-formed composite siding panel on which the present invention may be advantageously used is manufactured by Progressive Foam Technologies of Beach City, Ohio.
[0019] With reference to FIG. 2 , the composite siding product 10 is further illustrated. As illustrated in FIG. 2 , the rear face of the backing 14 can include a drainage plane made up of a grid network that can include a plurality of drainage grooves 19 . As shown in the example of FIG. 2 , the drainage grooves 19 can be positioned in a diamond pattern and can be set apart with a spacing of one inch. As water flows through the grid made up of the drainage grooves 19 , the water can flow into a plurality of exit grooves 20 . The exit grooves 20 can be positioned on a pocketed area 21 of the backing 14 . The exit grooves 20 can intersect the drainage grooves 19 . The exit grooves 20 can facilitate the water to travel into at least one weep hole 13 . After exiting the at least one weep hole 13 , the water can be harmlessly directed to the exterior surface of the siding component 12 and ultimately to the ground.
[0020] As illustrated in FIG. 3A , each set of drainage grooves 19 can be arranged in a diamond pattern at roughly a 30° angle from a vertical orientation. It is understood, that, as will be described below, the grooves can be positioned in a wide variety of angles and in a wide variety of patterns.
[0021] With reference to FIGS. 3B-3D , there is illustrated a plurality of examples of grid arrangements. These arrangements can include a diagonal pattern as illustrated in FIG. 3B , a vertical pattern as illustrated in FIG. 3C , and/or and a square pattern with the drainage grooves 19 positioned at an angle of 45° from the vertical orientation as illustrated in FIG. 3D .
[0022] With reference to FIG. 4 , the preferred profile of each drainage groove 19 and each exit groove 20 is illustrated. By way of example and not limitation, each drainage groove 19 and each exit groove 20 can have a depth of approximately {fraction (1/16)} to ⅛ of an inch, inclusive. In the preferred embodiment, each drainage groove 19 and exit groove 20 can have a tapered or rounded bottom 23 to cause the water to flow with reduced surface tension. Each drainage groove 19 and each exit groove 20 can include a tapered edge 21 to encourage water to flow freely into each groove. As water is drawn into the grid, a syphoning effect will cause water flow to increase.
[0023] The drainage plane of the present invention may be formed in a wide variety of ways. By way of example and not limitation, the drainage plane can be formed by molding the drainage grooves 19 and the exit grooves 20 into the rear face of the backing 14 , and/or the drainage grooves 19 , and the exit grooves 20 can be cut into the rear face of the backing 14 using hot wires or the like. | An apparatus and method for a drainage system of an exterior wall of a building comprising insulation having a rear face for contact with the exterior wall of the building and a drainage plane positioned on the rear face for removal of water from the exterior wall. | 4 |
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