Method for forming a film on a constituent part in a compressor

Information

  • Patent Grant
  • 6487958
  • Patent Number
    6,487,958
  • Date Filed
    Thursday, January 18, 2001
    23 years ago
  • Date Issued
    Tuesday, December 3, 2002
    21 years ago
Abstract
The object of the present invention is to form a film of a high quality on a constituent part in a compressor.The compressor has a swash plate as a constituent part to be filmed. The swash plate on which the film is to be formed is arranged on a seat of a film forming device. An adhesive layer is formed to the end surfaces of the swash plate in advance. A sheet to form a film is absorbed to a hollow body of a suction device of the film forming device, and press-contacted to the swash plate. The sheet is thus adhered to the end surface of the swash plate.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a constituent part in a compressor and a method for forming a film on the constituent part in a compressor.




Methods for coating a lubricating coating material on constituent parts such as a swash plate and a piston in a compressor are disclosed in Japanese Unexamined Patent Publications No.10-26081 and No.11-173263.




In a roller coating method according to Japanese Unexamined Patent Publication No.10-26081, a coating material is applied on a peripheral surface of a metal roller, and the coating material on the metal roller is transferred on a peripheral surface of a printing roller, which is made of a synthetic rubber, and then the coating material transferred on the peripheral surface of the printing roller is applied to a piston. The metal roller contacts the printing roller, and the printing roller contacts the piston to be coated. The coating material on the metal roller is adjusted to be predetermined thickness by a comma roller before transferred to the printing roller.




In a pad method according to Japanese Unexamined Patent Publication No.11-173263, a coating material prepared on a concave printing plate at a predetermined thickness and in a predetermined shape is transferred to a pad, and the coating material on the pad is printed on the constituent part to be coated.




In a coating method according to Japanese Unexamined Patent Publication No.10-26081, a line is formed on a coating film passing between a comma roller and a metal roller when a foreign substance is got into a clearance therebetween. This line is transferred to the film applied on the piston, so the quality of the film is deteriorated. As long as the foreign substance is not removed, the line is formed on every film of a subsequent piston to be filmed.




In a coating method according to Japanese Unexamined Patent Publication No.11-173263, a film is creased if the pad is deformed ununiformly. When a contacting surface of the pad with the constituent part is plane, a film is not satisfactorily formed since air is involved therebetween. When the contacting surface of the pad is in a convex curved shape so that it prevents air from being involved in, the thickness of the film is not uniform. For the closer to the center of the contacting surface it is, the stronger the contacting force of the pad against the constituent part becomes. Therefore, the film needs to be dried, calcinated, and then polished so that the thickness of it is adjusted.




SUMMARY OF THE INVENTION




Accordingly, it is an object of the present invention to form a film of a high quality on a constituent part in a compressor.




To achieve the above object, the present invention relates to a method for forming a film on a region of the constituent part, and the film is formed by adhering a sheet to form a film to the region so as to fit the shape of the region.




Furthermore, the present invention has following features. The sheet, which is fitted to the shape of the region, is formed. Afterward the sheet is adhered to the region, whereby the film is formed. The film of a uniform thickness is easily formed.




Furthermore, the present invention has following features. The sheet is a resin sheet containing a solid lubricant. The resin sheet containing the solid lubricant is effective to form a film so as to improve slidability.




Furthermore, the present invention relates to the constituent part in the compressor, and the film is formed in the region of the constituent part. According to the present invention, the film of a uniform thickness is easily formed, and adhered to the constituent part in the compressor.




Furthermore, the present invention has following features. The compressor is a swash plate type compressor, and the constituent part is the swash plate. The swash plate is integrally rotated with a drive shaft. The rotation of the swash plate through the shoes is converted into the reciprocating movement of pistons. The region to be filmed is the sliding region of the swash plate to the shoes. The sliding region of the swash plate to the shoes is suitable for the region to be filmed.




Furthermore, the present invention has following features. An adhesive layer is arranged on the region to be filmed, and the sheet is adhered over the region through the adhesive layer. When the adhesive layer is arranged on the region in advance, it is easy to adhere the sheet to the region.











BRIEF DESCRIPTION OF THE DRAWINGS




The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:





FIG. 1

is a cross-sectional side view illustrating a compressor according to a first embodiment of the present invention;




FIG.


1


(


a


) is an enlarged partial cross-sectional view of FIG.





FIG. 2

is a cross-sectional view illustrating a film forming device;




FIG.


2


(


a


) is an enlarged cross-sectional view of a suction device in

FIG. 2

;





FIG. 3

is a cross-sectional view illustrating adhesion of a sheet to form a film to a swash plate;




FIG.


3


(


a


) is a front view illustrating an adhesive layer arranged on an end surface in

FIG. 3

;





FIG. 4

is a partially omitted front view illustrating a second embodiment and a support shaft extending from a second driving device, at a position over a feeding plate;





FIG. 5

is a partially omitted front view illustrating the second embodiment and the support shaft extending from the second driving device, at a position over a seat;




FIG.


6


(


a


) is a cross-sectional view illustrating the condition before an absorption roller contacts a feeding plate;




FIG.


6


(


b


) is a cross-sectional view illustrating the condition that the absorption roller contacts the feeding plate;




FIG.


6


(


c


) is a cross-sectional view illustrating the condition that the sheet to form a film is adhered on a peripheral surface of the absorption roller;




FIG.


7


(


a


) is a cross-sectional view illustrating the condition before the absorption roller contacts a swash plate;




FIG.


7


(


b


) is a cross-sectional view illustrating the condition that the absorption roller contacts the swash plate;




FIG.


7


(


c


) is a cross-sectional view illustrating the condition that the sheet to form a film is adhered to the swash plate;





FIG. 8

is a schematic plan view illustrating the movement of the absorption roller; and





FIG. 9

is a development view of the peripheral surface of the absorption roller.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




A first embodiment according to the present invention will now be described with reference to

FIGS. 1

to


3


.




An inner construction of a variable displacement compressor is illustrated in

FIG. 1. A

cylinder block


11


is connected to a rear end of a front housing


12


and to a front end of a rear housing


19


. The cylinder block


11


, the front housing


12


, and the rear housing


19


constitute a housing assembly. A drive shaft


13


is inserted in the front housing


12


and the cylinder block


11


forming a crank chamber


121


. The drive shaft


13


receives the drive power from the outer driving source such as a vehicle engine. A rotary support member


14


is mounted around the drive shaft


13


, and a swash plate


15


is supported slidably and inclinably in the axial direction of the drive shaft


13


. A pair of brackets


151


is integrally formed with the swash plate


15


made of steel, and a pair of guide pins


16


is mounted on the bracket


151


. The guide pin


16


is slidably inserted into a respective guide hole


141


formed on the rotary support member


14


. The swash plate


15


is rotated integrally with the drive shaft


13


and inclinably in the axial direction of the drive shaft


13


by the association between the guide hole


141


and the guide pin


16


. The inclination of the swash plate


15


is guided by the slide guide relation between the guide hole


141


and the guide pin


16


, and by a slide support of the drive shaft


13


.




The inclination of the swash plate


15


is adjusted under the pressure control in the crank chamber


121


. When the pressure in the crank chamber


121


increases, the inclination of the swash plate


15


decreases. When the pressure in the crank chamber


121


decreases, the inclination of the swash plate


15


increases. The refrigerant in the crank chamber


121


flows into a suction chamber


191


in a rear housing


19


through a pressure release passage, which is not illustrated. The refrigerant in a discharge chamber


192


in the rear housing


19


is supplied into the crank chamber


121


through a pressure supply passage, which is not illustrated. A capacity control valve


25


is arranged in the pressure supply passage, and the flow rate of the refrigerant supplied from the discharge chamber


192


to the crank chamber


121


is adjusted by the capacity control valve


25


. When the flow rate of the refrigerant increases, the pressure in the crank chamber


121


increases. When the flow rate of the refrigerant decreases, the pressure in the crank chamber


121


decreases. That is, the inclination of the swash plate


15


is adjusted by the capacity control valve


25


.




The abutment between the swash plate


15


and the rotary support member


14


regulates the maximum inclination of the swash plate


15


. The abutment between a circular clip


24


around the drive shaft


13


and the swash plate


15


regulates the minimum inclination of the swash plate


15


.




A plurality of cylinder bores


111


(only two of the cylinder bores are illustrated in

FIG. 1

) are arranged around the drive shaft


13


in the cylinder block


11


. A piston


17


is accommodated in each cylinder bore


111


. As shown in

FIG. 1

the piston


17


at the upper side is at the top dead center, and the piston


17


at the lower side is at the bottom dead center. The rotating movement of the swash plate


15


integrally rotated with the drive shaft


13


is converted into the back-and-forth reciprocating movement of the piston


17


through a pair of semi-spherical shoes


18


A and


18


B, and the piston


17


moves back and forth in the cylinder bore


111


. The shoe


18


A made of steel slides on one sliding surface


30


of the swash plate


15


, and the shoe


18


B made of steel slides on another sliding surface


31


of the swash plate


15


.




The suction movement of the piston


17


(the movement from right to left in

FIG. 1

) draws the refrigerant in the suction chamber


191


into the cylinder bore


111


through an intake port


201


of a valve plate


20


, pushing away a suction valve


211


of a suction valve plate


21


. The discharge movement of the piston


17


(the movement from left to right in

FIG. 1

) discharges the refrigerant in the cylinder bore


111


into the discharge chamber


192


through a discharge port


202


of the valve plate


20


, pushing away a discharge valve


221


of a discharge valve plate


22


. A retainer


231


of a retainer plate


23


regulates the opening degree of the discharge valve


221


by the abutment therebetween.




The discharge chamber


192


and the suction chamber


191


are connected through an external refrigerant circuit


26


. The refrigerant in the discharge chamber


192


flows outside the compressor, through a condenser


27


, an expansion valve


28


and an evaporator


29


in the external refrigerant circuit


26


, and returns to the suction chamber


191


.




A connecting portion


171


is formed on the piston


17


, and a pair of semi-spherical concave portions


172


and


173


is formed on the connecting portion


171


. As shown in FIG.


1


(


a


), the shoe


18


A sliding on one sliding surface


30


of the swash plate


15


is held in the concave portion


172


to be fitted therein, and the shoe


18


B sliding on another sliding surface


31


of the swash plate


15


is held in the concave portion


173


to be fitted therein.




Films


32


and


33


are formed on the end surfaces


152


and


153


which are film formed regions of the sliding surfaces


30


,


31


of the swash plate


15


. The film


32


is adhered to the end surface


152


through an adhesive layer


44


, and the film


33


is adhered to the end surface


153


through an adhesive layer


45


. The surface of the film


32


forms the sliding surface


30


, and the surface of the film


33


forms the sliding surface


31


. The films


32


and


33


are made of thermosetting resin containing solid lubricants such as molybdenum disulfide, tungsten disulfide and graphite. The adhesive layers


44


and


45


are made of adhesives of thermosetting resin.




The films


32


and


33


are formed by the film forming device as shown in

FIG. 2. A

first driving device


35


and a second driving device


36


are mounted on a base frame


34


. A feeding plate


37


, which is horizontally arranged, is reciprocated by the first driving device


35


. The feeding plate


37


is horizontally reciprocated at a predetermined height. The feeding plate


37


is reciprocated between the feeding position shown in FIG.


2


and the preparing position shown in FIG.


3


. An annular holding slot


371


is recessed on the feeding plate


37


.




A suction device


39


is mounted beneath a support shaft


38


which is vertically and horizontally moved by the second driving device


36


. As shown in FIG.


2


(


a


), the suction device


39


is composed of a blower


40


and a cylindrical hollow body


41


, and a plurality of suction bores


412


are arranged in a bottom wall


411


of the hollow body


41


annularly around an axial line


413


of the hollow body


41


.




A seat


42


is arranged on the extended position of the feeding plate


37


. The swash plate


15


on which films are to be formed is arranged on the seat


42


. In

FIGS. 2 and 3

, a swash plate


15


is mounted on the seat


42


so that the end surface


152


is upward.




When the feeding plate


37


is at the preparing position shown in

FIG. 3

, an annular sheet


43


to form a film is supplied into a holding slot


371


. The sheet


43


is made of thermosetting resin containing the solid lubricants such as molybdenum disulfide, tungsten disulfide and graphite, and is formed in predetermined thickness in advance. When the feeding plate


37


which holds the sheet


43


in the holding slot


371


is at the feeding position shown in

FIG. 2

, the suction device


39


is lowered to the solid line position from the chain line position in FIG.


2


. At the lowered position, the bottom wall


411


of the hollow body


41


is abutted to the feeding plate


37


, and then a blower


40


operates. The blower


40


generates a suction force at the suction bore


412


, and the sheet


43


is absorbed to the bottom wall


411


. The suction device


39


absorbing the sheet


43


is raised to the chain line position in

FIG. 2

, and is moved horizontally to the chain line position in FIG.


3


. The suction device


39


is lowered to the solid line position in

FIG. 3

, and the end surface


152


of the swash plate


15


is contacted by the sheet


43


. Then the blower


40


stops operation. As shown in FIG.


3


(


a


), the adhesive layer


44


is formed on the end surface


152


of the swash plate


15


in advance. The adhesive layer


45


is also formed on the end surface


153


of the swash plate


15


. The sheet


43


is adhered to the end surface


152


through the adhesive layer


44


by press-contacting to the end surface


152


.




Once the sheet


43


is adhered to the end surface


152


, the suction device


39


is moved to the solid line position in FIG.


2


through the chain line positions in

FIGS. 3 and 2

. Then the new sheet


43


on the holding slot


371


is absorbed to the bottom wall


411


of the hollow body


41


. The swash plate


15


is turned over so that the end surface


153


is upward. The new sheet


43


absorbed to the bottom wall


411


of the hollow body


41


is adhered to the end surface


153


as well as to the end surface


152


.




Then the swash plate


15


adhered the sheets


43


and


44


is sent to the calcination process. The sheets


43


on the end surfaces


152


and


153


become the films


32


and


33


through the calcination process.




In the first embodiment the following effects can be obtained.




(1-1) The sheets


43


adhered to the end surfaces


152


and


153


are, for example, formed from a strip-shaped thermosetting resin sheet by a blanking. Such thermosetting sheet is formed by dispersing the fluid thermosetting resin in a sheet on the surfaces of a glass or a stainless plate and the like, and then drying. The strip-shaped thermosetting resin sheet is simply made so that the sheet has a desired and uniform thickness. Accordingly, the method for forming the films


32


and


33


by adhering the sheet


43


is effective to provide the films


32


and


33


having a desired and uniform thickness.




(1-2) When the thickness of the sheet


43


is predetermined in consideration of the change of the film thickness accompanied by calcinating the films


32


and


33


, the surface of the films


32


and


33


do not need to be polished to adjust the film thickness.




(1-3) The resin containing the solid lubricant is effective to form the films


32


and


33


which can improve the slidability.




(1-4) The end surfaces


152


and


153


of the swash plate


15


are plane. The adhesion of the sheet to the plane is easier than to the curved surface. Accordingly, the end surfaces


152


and


153


, which are sliding regions of the swash plate


15


to the pair of shoes


18


A and


18


B, are suitable for the regions to form the films


32


and


33


by adhering the sheet


43


.




Next, a second embodiment will be explained with reference to

FIGS. 4

to


9


. The same reference numerals as the first embodiment are given to the components which are common to the first embodiment.




As shown in

FIG. 4

, a support base plate


46


is mounted beneath the bottom end of a support shaft


38


A driven by a second driving device


36


A, and a motor


47


is mounted beneath the bottom surface of the support base plate


46


. An absorption roller


48


in a hollow body is mounted around an output shaft


471


of the motor


47


. A concave portion


481


, whose shape is appropriate to avoid the interference with the swash plate


15


, is formed on the peripheral surface of the absorption roller


48


. As shown in

FIG. 9

, when the peripheral surface of the absorption roller


48


is developed, the shape of the concave portion


481


is in a circle larger than a cylindrical base portion


154


of the swash plate


15


.




As shown in

FIGS. 8 and 9

, an annular absorbing portion


482


is formed on the peripheral surface of the absorption roller


48


. A developed plan of the peripheral surface of the absorption roller


48


is shown in FIG.


9


. The absorbing portion


482


is made of a material having gas permeability. The absorbing portion


482


is almost the same in size as the sheet


43


prepared in a holding slot


441


shown in FIG.


8


. As shown in

FIG. 4

, a blower


49


is mounted beneath the bottom surface of the support base plate


46


. The blower


49


is connected to the output shaft


471


, and a suction passage


472


(which is illustrated in

FIGS. 6 and 7

) is formed in the output shaft


471


. The suction passage


472


connects to the hollow portion of the absorption roller


48


. A sucking force is caused on the outer surface of the absorbing portion


482


when the blower


49


operates.




When the sheet


43


is prepared in the holding slot


441


as shown in

FIG. 8

while the feeding plate


37


is at the feeding position as shown in

FIG. 4

, the absorption roller


48


is arranged at the predetermined height as shown in FIG.


6


(


a


) and a solid line position r


0


as shown in FIG.


8


. Then the absorption roller


48


is lowered at the solid line position in

FIG. 8

, and press-contacts to the feeding plate


37


as shown in FIG.


6


(


b


). The absorption roller


48


moves in the direction of an arrow R


1


in

FIG. 8

at a certain speed while the absorption roller


48


moves to the position in FIG.


6


(


c


) with rotating in the direction of an arrow Q


1


in FIG.


6


(


b


) at a certain speed, and at the same time the blower


49


and the motor


47


operate with maintaining this contact. That is, the absorption roller


48


rotates so as to roll on the feeding plate


37


. The moving speed of the absorption roller


48


is the same as its peripheral speed, and the absorbing portion


482


contacts the sheet


43


in the holding slot


441


with rolling. Accordingly, the sheet


43


in the annular holding slot


441


is transferred to the peripheral surface of the absorbing portion


482


as it is shown in

FIG. 9

, and then the motor


47


stops operating.




The absorption roller


48


absorbing the sheet


43


is raised to the above-mentioned predetermined height from the position in FIG.


6


(


c


). That is, the absorption roller


48


is raised at the chain line position r


1


in FIG.


8


. The absorption roller


48


in

FIG. 4

denotes this raised position. Next, the absorption roller


48


horizontally moves in the direction of an arrow R


2


in FIG.


8


. The absorption roller


48


is arranged at the above-mentioned predetermined height in FIG.


7


(


a


) and at the chain line position r


2


in

FIG. 8

by the horizontal movement. The absorption roller


48


in

FIG. 5

denotes the arranged position. Next, the absorption roller


48


is lowered at the chain line position r


2


in

FIG. 8

, and press-contacts to the end surface


152


of the swash plate


15


as shown in FIG.


7


(


b


). As shown in

FIG. 8

, the adhesive layer


44


is adhered to the end surface


152


of the swash plate


15


in advance. The absorption roller


48


moves in the direction of an arrow R


3


in

FIG. 8

at a certain speed while the absorption roller


48


moves to the position in FIG.


7


(


c


) with rotating in the direction of an arrow Q


2


in FIG.


7


(


b


) at a certain speed, at the same time the motor


47


operates with maintaining this press-contact. The moving speed of the absorption roller


48


is the same as its peripheral speed. Therefore, the absorption roller


48


moves from the position in FIG.


7


(


b


) to the position in FIG.


7


(


c


) with rolling on the swash plate


15


. The sheet


43


on the peripheral surface of the absorbing portion


482


of the absorption roller


48


is transferred and adhered to the end surface


152


of the swash plate


15


, with the shape of the sheet


43


maintained. The base portion


154


of the swash plate


15


enters in the concave portion


481


, so the base portion


154


does not interfere with the absorption roller


48


.




The absorption roller


48


, which adhered the sheet


43


to the swash plate


15


, is raised to the above-mentioned predetermined height from the position in FIG.


7


(


c


). That is, the absorption roller


48


is raised at the chain line position r


3


in FIG.


8


. Next, the absorption roller


48


moves horizontally in the direction of an arrow R


4


. By the horizontal movement, the absorption roller


48


is arranged at the above-mentioned predetermined height in FIG.


6


(


a


) and at the solid line position r


0


in FIG.


8


. When the absorption roller


48


returns to the position in FIG.


6


(


a


), a new sheet


43


is supplied in the holding slot


441


and the holding slot


441


is arranged at the preparing position S in FIG.


4


. Then the sheet


43


is absorbed to the absorption roller


48


, and the adhesion of the sheet


43


to another end surface


153


of the swash plate


15


or to a new swash plate


15


to be filmed are also performed in turn.




In the second embodiment the following effects can be obtained.




(2-1) The absorption roller


48


leaves from the feeding plate


37


and the swash plate


15


, in every adhering operation of the sheet


43


. Accordingly, a foreign substance does not continue to be absorbed to the absorption roller


48


, even if the foreign substance is absorbed to the absorption roller


48


when the sheet


43


is adhered to the absorption roller


48


, or, the foreign substance is absorbed to the absorption roller


48


when the sheet


43


is adhered to the swash plate


15


. As a result, all the films


32


and


33


are not damaged by the foreign substance after the foreign substance is absorbed.




(2-2) The absorption roller


48


, which rolls on the feeding plate


37


at the same peripheral speed as the moving speed of the absorption roller


48


, absorbs the sheet


43


without creasing.




Furthermore, since the absorption roller


48


rolls on the swash plate


15


at the same peripheral speed as the moving speed of the absorption roller


48


, the sheet


43


is adhered to the swash plate


15


without creasing. That is, the sheet


43


supplied in the holding slot


441


is adhered to the swash plate


15


with the shape of the sheet


43


maintained.




Accordingly, the excellent films


32


and


33


are obtained.




In the present invention the following embodiments can be applied.




(1) The piston


17


is applied as the constituent part to be filmed, and the peripheral surface of the piston


17


which slides on the peripheral surface of cylinder bore


111


is applied as the region to be filmed.




(2) After the sheet is adhered to the region to be filmed, the extra portion of the sheet is removed.




(3) The sheet is adhered to the region to be filmed with blanking process at the same time so as to fit the shape of the region.




(4) As disclosed in Japanese Unexamined Patent Publication No.11-193780, a metal sliding layer which is excellent in slidability is formed on the surface of the swash plate, and the film of the present invention is adhered thereon. The film can be a protective coat of the sliding layer.




(5) The present invention is applied to a swash plate of a fixed capacity type swash plate compressor.




As described above, in the present invention the film is formed by adhering the sheet to the region so as to fit the shape of the region, so the excellent effect that the film of a high quality is formed on the constituent part in the compressor can be performed.




Therefore the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein but may be modified within the scope of the appended claims.



Claims
  • 1. A method for forming a film on a constituent part in a compressor, comprising:adhering a solid sheet to the constituent part so as to fit the shape of a region where film is to be formed, wherein the solid sheet has been formed in advance to a predetermined thickness; and forming the film by subjecting the solid sheet to a calcination process.
  • 2. A method for forming a film on a constituent part in a compressor according to claim 1, wherein said method further comprising:forming the solid sheet so as to fit the shape of the region and thereafter adhering the fitted solid sheet to the region.
  • 3. A method for forming a film on a constituent part in a compressor according to claim 1, wherein the method further comprising:forming an adhesive layer on the region and adhering the solid sheet to the region through the adhesive layer.
  • 4. A method for forming a film on a constituent part in a compressor according to claim 1, wherein the solid sheet comprises thermosetting resin containing a solid lubricant.
  • 5. A method for forming a film on a constituent part in a compressor according to claim 1, wherein polishing is not performed after adhering the sheet.
  • 6. A constituent part in a compressor,the constituent part being obtained by the step consisting essentially of adhering a solid sheet to form a film to the constituent part so as to fit the shape of a region where film is to be formed, wherein the solid sheet has been formed in advance to a predetermined thickness; and forming the film by subjecting the solid sheet to a calcination process.
  • 7. A constituent part in a compressor according to claim 5, wherein the compressor is a swash plate type compressor comprising:a housing having a plurality of cylinder bores; a drive shaft rotatably supported by the housing; a swash plate integrally rotatable with the drive shaft; a piston accommodated in each of the cylinder bores; and a pair of shoes positioned between the swash plate and the piston for converting rotational movement of the swash plate to reciprocating movement of the piston, wherein the pair of shoes slides therebetween; wherein the constituent part is the swash plate; and wherein region of the swash plate where film is to be formed are sliding regions to the pair of shoes.
Priority Claims (1)
Number Date Country Kind
2000-044715 Feb 2000 JP
US Referenced Citations (1)
Number Name Date Kind
5941160 Kato et al. Aug 1999 A
Foreign Referenced Citations (3)
Number Date Country
0 943 800 Sep 1999 EP
10-26081 Jan 1998 JP
11-173263 Jun 1999 JP