Fabric tensioning device for sewing machine

Information

  • Patent Grant
  • 6708632
  • Patent Number
    6,708,632
  • Date Filed
    Monday, December 30, 2002
    21 years ago
  • Date Issued
    Tuesday, March 23, 2004
    20 years ago
Abstract
The present invention provides a fabric tensing device for stretching fabric on a sewing machine.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to a fabric tensioning device for stretching work fabric in the sewing location of a sewing machine.




2. Description of Related Art




Devices for tensioning a piece of tube-like fabric, such as material for socks and wrist bands, using a cylindrical frame are used in embroidering on a sewing machine. One of such a fabric tensioning devices is disclosed in International Patent Publication Number WO00/53836. This device has a cylindrical frame


101


which is placed to cover the outside of the cylinder bed (not shown) of the sewing machine as shown in FIG.


11


. The cylindrical frame


101


includes a sewing window


102


for exposing the sewing area of the cylinder bed, a core material clamping member


105


for clamping down thick core material C against the cylindrical frame


101


, and a fabric clamping member


103


for clamping down the fabric and the core material C against the cylindrical frame


101


. The fabric is arranged to cover the core material C which is arranged to cover the sewing window


102


. The core material clamping member


105


is formed in a rectangular shape with a closed front end so that the core material C can be clamped in one stroke. The core material clamping member


105


is attached to the cylindrical frame


101


to be able to open and close vertically.




However, with this fabric tensioning device, the core material clamping member


105


clamps down the core material C from the rear to the front simultaneously on both the left and right side of cylindrical frame


101


. Therefore, the cylindrical shape of the core material C tends to be lower on the rear side or cause a localized deformation, thereby essentially making it difficult to properly fit the entire core material C around the circumference of cylindrical frame


101


. Thus, the core material C is difficult to set since it is necessary to straighten or restretch the stretched core material C.




SUMMARY OF THE INVENTION




The present invention provides a fabric tensioning device for a sewing machine that can solve the abovementioned problem by holding down the core material on the left side and the right side individually so that it can be easily stretched in a properly aligned manner on the outer periphery of the cylindrical frame.




In order to solve the abovementioned problem, the fabric tensioning device according to the present invention comprises a cylindrical frame having a sewing window, a core material clamping member for clamping down a core material against the cylindrical frame and a fabric clamping member for clamping down the fabric and the core material against the cylindrical frame. The core material covers the sewing window, and the fabric covers the core material. The fabric clamping member is able to open or close against the cylindrical frame. The core material clamping member consists of two members provided with one on each side of the left and right sides of the cylindrical frame. The two members extend in the axial (front and rear) direction and can open or close against the cylindrical frame independently.




The core material clamping members can open or close in either a vertical direction or a lateral direction. However, the two core material clamping members can be mounted on the left and right sides of the cylindrical frame at the rear ends of the two clamping members respectively. Therefore, the two core material clamping members can open or close their respective front end in the lateral direction in order to make it easier to stretch the core material at the same height on the front and rear against the cylindrical frame. Furthermore, tighteners can be provided protrusively on the outer surface of the cylindrical frame extending along the left and right edges of the sewing window in order to prevent the core material from slackening or deforming. A core material clamping member can be provided under each tightener.




The core material clamping member does not have a specific shape requirement. The core material clamping member can be made of a long rod or a strip extending in the axial (front and rear) direction. Several clamps along the axial direction can be provided on the inside of the core material clamping member so that the oblong core material clamping member can press down various parts of the core material. Additionally, a temporary latch can engage the cylindrical frame at the front end of the core material clamping member in order to hold the shape of the core material until the work fabric is stretched.




The fabric clamping material does not have a specific constitution requirement. The fabric clamping material can have two fabric clamps, one on each side of the left and right sides of the fabric clamping member, and a band that tightens the fabric clamping member and the core material clamping members together against the cylindrical frame. The two fabric clamps can face the core material clamping member from the outside. Slip guards made of processed fabric can be provided on the outer surface of the core material clamping members.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a side view of a cylinder bed according to an embodiment of the present invention.





FIG. 2

is a front view of the bed according to an embodiment of the present invention.





FIG. 3

is a disassembled perspective view showing a cylindrical frame guide device provided on the bed according to an embodiment of the present invention.





FIG. 4

is a perspective view of a fabric tensioning device of the bed according to an embodiment of the present invention.





FIG. 5

is a side view of the fabric tensioning device according to an embodiment of the present invention.





FIG. 6

is a partially broken front view of the fabric tensioning device according to an embodiment of the present invention.





FIG. 7

is a plan view of the fabric tensioning device according to an embodiment of the present invention.





FIG. 8

is a cross-sectional view showing how an core material and a work fabric are mounted on the fabric tensioning device according to an embodiment of the present invention.





FIG. 9

is a plan view showing how the core material and the work fabric are tensioned according to an embodiment of the present invention.





FIG. 10

is a cross-sectional view showing how the core material and the work fabric are tensioned according to an embodiment of the present invention.





FIG. 11

is a perspective view of a fabric tensioning device of the prior art.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




An embodiment of the present invention on an embroidering sewing machine will be described below with reference to the accompanying drawings. A head


1


and a cylinder bed


2


are displaced in the vertical direction in the machine frame (not shown) of a sewing machine as shown in

FIGS. 1-2

. A needle


3


is attached to the bottom end of the head


1


while a bobbin case


4


and a needle plate


11


are provided at the front end of the cylinder bed


2


. A Y-direction moving body


5


is supported by the top surface of the cylinder bed


2


, and a base plate


6


is connected vertically to the moving body


5


. Three rollers


8


are displaced on the front side of the base plate


6


in order to support a drive ring


7


while two guide rollers


10


are provided on the back side of the base plate


6


and engage two bottom grooves


9


on the left and right sides of the cylinder bed


2


.




A X-direction moving body


13


is supported via a rail


12


provided on the top of the Y-direction moving body


5


while a pulley


14


is provided at the left and right ends of moving body


13


respectively. A wire rope


15


is provided on the pulleys


14


and is tightly stretched by means of a spring


16


while the rope


15


is wrapped around the middle of the drive ring


7


. The Y-direction moving body


5


and the X-direction moving body


13


are connected to a sewing frame driving device (not shown) of the sewing machine, and the Y-direction moving body


5


strokes the drive ring


7


in a reciprocating manner in the axial direction (front and rear direction) of the cylinder bed


2


via the base plate


6


while the X-direction moving body


13


rotates the drive ring


7


in a reciprocating manner around the axis of the cylinder head


2


via the wire rope


15


.




A cylindrical frame


19


of the fabric tensioning device


18


is placed to cover the outside of the cylinder bed


2


in an embroidering process of a piece of tube-like fabric such as material for socks and wrist bands. The cylindrical frame


19


is attached to the drive ring


7


via the rear end of the mounting part


19




a


. A latching piece


20


and a flange


21


are provided protrusively on the rear outer periphery of the cylindrical frame


19


while a lever


22


that engages with the latching piece


20


and a spring


23


that elastically contacts with flange


21


are provided on the drive ring


7


. Thus, the cylindrical frame


19


is connected tightly to the drive ring


7


via the lever


22


and the spring


23


. The cylindrical frame


19


and the drive ring


7


are driven together in the axial and circumferential directions relative to the axis of the cylinder bed


2


in order to sew the fabric stretched around the cylindrical frame


19


in the cooperation of the needle


3


and the bobbin case


4


.




A pair of arms


25


protrude on the left and right sides of the front end of the cylinder bed


2


, and a needle plate


11


is affixed horizontally on arms


25


as shown in FIG.


3


. Curved surfaces


11




a


are formed on the left and right shoulder areas of the needle plate


11


close to the inner surface of the cylindrical frame


19


. A boss


26


equipped with a needle hole


26




a


protrudes low in the center flat area of needle plate


11


. The front end of a bobbin case drive shaft


31


extends into an opening


29


formed below the needle plate


11


, and the bobbin case


4


is mounted on the bobbin case drive shaft


31


.




A guide member


27


is provided in opening


29


for supporting the cylindrical frame


19


from the inside. The guide member


27


consists of a connecting part


27




a


in the rear end and two side wall parts


27




b


on the left and right sides, together forming a rectangular shape. The connecting part


27




a


is affixed detachably with a screw


32


to the front end surface of the cylinder bed


2


below the bobbin case drive shaft


31


. The side walls


27




b


cover the outside of the arms


25


. A curved plate


33


is affixed by welding or the like on the outside of each side wall part


27




b


, and the curved plates


33


form a partial cylindrical surface


30


that contacts concentrically with the inside of the cylindrical frame


19


for the side wall parts


27




b.






A protection cover


28


is provided below the guide member


27


, and the cover


28


covers the bobbin case


4


from its underside. The protection cover


28


consists of flat parts


28




a


and a curved part


28




b


forming a U-shape as it is viewed from the front, wherein the curved part


28




b


forms a partial cylindrical surface


36


having the same curvature as the partial cylindrical surface


30


of the guide member


27


for the cover


28


. Semispherical protrusions


34


are provided on the flat parts


28




a


while holes


35


are provided on the side walls


27




a


to fit the protrusions


34


. The protection cover


28


is mounted detachably on the guide member


27


by means of fitting between the protrusions


34


and the holes


35


as the flat parts


28




a


are inserted on the inside of the side wall parts


27




b.






The cylindrical frame


19


comprises a sewing window


37


that exposes the needle plate


11


, a core material clamping member


38


that clamps down the core material C covering the sewing window


37


against the cylindrical frame


19


, a fabric clamping member


39


that clamps down the work fabric W covering the core material C together with the core material C against cylindrical frame


19


, and a support member


40


that supports the core material C and the work fabric W in the middle position of sewing window


37


, as shown in

FIGS. 4-7

. The core material C is a shape-keeping material that prevents the work fabric W from sinking and is made of a material such as cardboard, unwoven fabric, etc. It is possible to sew by stretching the work fabric W directly over the cylindrical frame


19


without using the core material C if the work fabric W consists of a rigid material such as leather, felt, etc.




The sewing window


37


has a length corresponding to the axial stroke length of the cylindrical frame


19


while a slip guard


42


made of rubber is glued on the cylindrical frame


19


along the respective front and rear edges of the sewing window


37


. A tightener


43


made of a steel strip or rubber is protrusively provided along the left and right side edges of the sewing window


37


. A support member


40


is formed into a curved shape having a curvature approximately equal to that of the outside diameter of the cylindrical frame


19


and is fastened at fastening areas


40




a


at each end with screws


44


that are screwed into screw holes


43




a


of the tighteners


43


in an axially adjustable manner spanning over the sewing window


37


. A notch


45


is formed on the rear mounting part


19




a


of the cylindrical frame


19


to allow the spring


23


of the drive ring


7


to enter. The inside of the front end of the cylindrical frame


19


is attached with an annular plate


46


, and a portion of the annular plate


46


is provided with a protruding positive stop


47


for positioning the core C from the front end.




The core material clamping member


38


made of a steel strip is formed in an oblong shape in the axial direction, which is longer than the sewing window


37


, on the left and right hand sides of the cylindrical frame


19


respectively under the tightener


43


. The rear end of the core material clamping member


38


is affixed to the flange


21


with a screw


49


on the left and right sides of cylindrical frame


19


respectively while the front end of the core material clamping member


38


is provided in such a way as to be able to open individually to the left and right relative to the cylindrical frame


19


. Clamping pieces


50


are provided at multiple places inside the core material clamping member


38


and bend in an angle going from top to bottom for elastically contacting the core material C. Temporary latches


51


bend inward at the front end of the core material clamping member


38


in such a way that the temporary latches


51


can elastically engage the annular plate


46


through notches


52


provided on the cylindrical frame


19


in order to hold the core material clamping member


38


temporarily in a closed state.




The fabric clamping member


39


comprises, on the left and right sides, a pair of fabric clamps


56


that are oblong in the axial direction and open at the front end. The rear ends of the left and right fabric clamps


56


are connected by a connecting part


55


thus causing the fabric clamping member


39


to have a substantially rectangular shape with an open-ended front. Each fabric clamp


56


is made of a steel strip having a length approximately equal to that of the core material clamping member


38


, and the fabric clamps


56


face the core material clamping member


38


from the outside. Slip guards


53


are made of rubber plates with grooves and are intended to sandwich the work fabric W with the fabric clamps


56


that are glued on the outside of the core material clamping member


38


. A bracket


57


is attached to the left side of the connecting part


55


which is made of a steel plate in a shape that spans the cylindrical frame


19


. A threaded shaft


58


is provided on the bracket


57


on the outside of the left fabric clamp


56


, and the fabric clamping member


39


is fastened to the flange


21


of the cylindrical frame


19


by means of the threaded shaft


58


so that the fabric clamping member


39


can open or close in the lateral (left and right) direction.




An oblong surface fastener tape


60


is adhered to the outside surface of each fabric clamp


56


, and a surface fastener belt


61


with open ends is latched to the tape


60


in such a way as to be adjustable in the axial direction in order to coordinate with the support member


40


. An engaging hole


62


is provided at the front end of the left and right fabric clamps


56


, and a surface fastener belt


63


is threaded through the engaging hole


62


. The left and right fabric clamps


56


and the left and right core material clamping members


38


can be tightened against the cylindrical frame


19


in the front and rear of the needle plate


11


where the sewing actions occur by means of the front and rear fastener belts


61


and


63


. The surface fastener belts


61


and


63


can be provided with surface fasteners for the entire surface on the front and back or can be provided only on both ends.




The method of using the fabric tensioning device


18


in the sewing machine constituted as described above will be described as follows. In embroidering a piece of tube-like fabric, the cylindrical frame


19


is positioned to cover the outside of the cylinder bed


2


, the mounting area


19




a


is fitted into the drive ring


7


, the flange


21


is clamped to the spring


23


, the lever


22


is engaged with the engaging piece


20


, and the cylindrical frame


19


is mounted tightly on the drive ring


7


, as shown in FIG.


1


.




Next, the fabric clamping member


39


is opened toward the left side of the cylindrical frame


19


, and the core material C is moved to abut against the positive stop


47


, as shown in

FIGS. 7-8

. The core material C is supported by the supporting member


40


, covers the sewing window


37


, and is clamped down against the cylindrical frame


19


to be stretched by means of the core material clamping members


38


on the left and right sides. The following operating advantages can be achieved with the fabric tensioning device


18


of this embodiment:




(1) Since the two core material clamping members


38


on the left and right sides are attached to the cylindrical frame


19


in such a way as to be able to open independently, it is possible to clamp down the core material C against the cylindrical frame


19


on the left and right sides independently and align it against the outer periphery of the cylindrical frame


19


easily and accurately. The shape of the remaining portion of the core material C can be adjusted, and the right side of the core material can be clamped by the right core material clamping member


38


to stretch the entire core material C in a smooth cylindrical shape after clamping the left side of the core material with the left core material clamping member


38


. The order of the steps can be reversed to start with the right side.




(2) Since the front ends of the left and right side core material clamping members


38


are arranged to be able to open toward the left and right sides of the cylindrical frame


19


respectively, the core material C is less likely to be stretched in a skewed manner and the material can be easily stretched against the cylindrical frame


19


evenly from the front to the rear at the same height. This is in contrast to the prior art wherein the clamping member opened and closed in the vertical direction.




(3) Since the temporary latches


51


are provided at the front end of the core material clamping member


38


, the core material C can be held in a smooth, cylindrical shape by temporarily latching one side of the core material C, which makes it easy to adjust the other side of the work fabric W with both hands and to stretch it out neatly.




(4) Since the core material clamping members


38


are provided below the tighteners


43


, it is possible to securely prevent the core material C from slackening and deformation while it is temporarily latched.




(5) Since the multiple clamping pieces


50


are provided in the inside of the core material clamping members


38


, it is possible to hold various parts of the core material C with an even force using the core material clamping members


38


which are oblong in the axial direction.




Next, the work fabric W is placed on top of the core material C as shown in

FIGS. 9-10

. The fabric clamping member


39


is closed, and the work fabric W is clamped down against the cylindrical frame


19


via the core material C with the left and right fabric clamps


56


. Next, both ends of the front and rear surface fastener belts


61


and


63


are moved to contact and stick together, and they are tightened in order to cause the fabric clamps


56


to tighten against the cylindrical frame


19


together with the core material clamping members


38


to stretch the work fabric W against the cylindrical frame


19


. The following operating advantages can be achieved with the fabric tensioning device


18


of this embodiment:




(6) Since the two fabric clamps


56


on the left and right sides are tightened against the cylindrical frame


19


by means of the two front and rear surface fastener belts


61


and


63


, the work fabric W is evenly clamped down on four sides of the needle plate


11


, thus making it possible to stretch it out securely on the cylindrical frame


19


without causing any clamp marks or slack.




(7) Since the fabric clamping member


39


is provided in such a way as to be able to open or close in the lateral direction, the core material C and the work fabric W can be neatly and quickly spread out to cover the fully exposed sewing window


37


as shown in FIG.


7


.




(8) Since the fabric clamping member


39


is pivot mounted on the flange


21


via the threaded shaft


58


located on the outside of the left side fabric clamp


56


, it is possible to provide a wide space between the left side fabric clamp


56


and the cylindrical frame


19


when the fabric clamping member


39


is opened, thereby allowing the core material C and the work fabric W to be inserted easily in the space as shown in FIG.


8


.




(9) Since the left and right fabric clamps


56


face the left and right core material clamping members


38


from the outside, they can be tightened together with two surface fastener belts


61


and


63


to hold the work fabric W and the core material C against the cylindrical frame


19


securely and simultaneously.




(10) Since the slip guards


53


are provided on the outside surfaces of the core material clamping members


38


, the work fabric W can be clamped without slack between the core material clamping members


38


and the fabric clamps


56


.




(11) Since the surface fastener belts


61


and


63


having open ends on one side are used, the fabric clamps


56


can be tightened by a one-touch operation without causing any slack.




(12) Since the rear surface fastener belt


61


is engaged with the surface fastener tape


60


in such a way as to be adjustable in the axial direction, it is possible to tighten the fabric clamps


56


closer to the back of the embroidering position as needed according to the embroidering pattern.




(13) Since the front surface fastener belt


63


is threaded through the engaging hole


62


of the fabric clamp


56


, the belt


63


is less likely to get lost.




The following operating advantages can be achieved with the sewing machine of this embodiment:




(14) Since the cylindrical frame


19


is guided by means of the guide member


27


, which is independent of the needle plate


11


, it is possible to install the needle plate


11


permanently on the cylinder bed


2


in order to use the needle plate


11


not only for the cylindrical frame


19


but also for other types of frames such as a rectangular frame or an annular frame, thus eliminating the need to replace the needle plate


11


for different applications.




(15) Since the curved surfaces


11




a


are provided on the left and right shoulder areas of the needle plate


11


close to and facing the inner surface of the cylindrical frame


19


, it is possible to feed the work fabric W smoothly without being stuck on the needle plate


11


and to provide a wide area on the needle plate


11


for supporting the work fabric W.




(16) Since the partial cylindrical surface


30


is formed on the left and right side walls


27




b


of the guide member


27


concentric and close to the cylindrical frame


19


, the cylindrical frame


19


can be guided parallel to the cylinder bed


2


with high precision.




(17) Since the guide member


27


is formed in an open-ended rectangular shape, it is possible to attach the guide member


27


rigidly on the cylinder bed


2


via the connecting part


27




a


, thus effectively preventing vibration.




(18) Since the partial cylindrical surface


30


is formed on the left and right side walls


27




b


of the guide member


27


, it is possible to install the bobbin case


4


and form a wide area for the partial cylindrical surface


30


, thereby using the limited space under the needle plate


11


effectively.




(19) Since the protection cover


28


is provided detachably on the guide member


27


, the bobbin case


4


is not exposed, thereby making it safer when the cylindrical frame


19


is not used. The bobbin case


4


can be removed or installed easily by removing the cover


28


during the bobbin exchange.




(20) Since the partial cylindrical surface


36


is formed on the protection cover


28


, the guide surface


36


provides a wide surface for guiding the cylindrical frame


19


in cooperation with the partial cylindrical surface


30


of the guide surface


27


.




This invention should not be construed to be restricted with the embodiment described above, but rather can be constructed in various other ways without leaving the gist of the invention as described below:




(a) To pivot-mount the fabric clamping member


39


by a shaft at the rear end so that it can open or close vertically;




(b) To form the entire structure of the fabric clamping member


39


with a rod material in an open-ended rectangular shape;




(c) To form a slit oblong in the axial direction in one of the fabric clamps


56


of the fabric clamping member


39


, and cause the rear belt


61


to engaged the slit in such a way as to make its position adjustable;




(d) To form the core material clamping member


38


with a rod material in an oblong shape in the axial direction;




(e) To support rotatably the core material clamping member


38


at its rear end via a shaft and a spring mechanism relative to the cylindrical frame


19


.




(f) To provide the core material clamping member


38


and the fabric clamps


56


in positions vertically separated on both the left and right sides of the cylindrical frame


19


; and




(g) To form a portion of the guide device for the cylindrical frame


19


that corresponds to the protection cover


28


integral with the guide member


27


and provide on the outside of the guide member


27


a partial cylindrical surface with an open portion at the top like a C-shape.




In the fabric tensioning device for a sewing machine according to the present invention, the two core material clamping members on the left and right sides are mounted on the cylindrical frame in such a way as to be opened or closed independently, so that they press down the core material on both sides of the cylindrical frame independently, thus making it possible to stretch the material easily while matching it properly on the outer circumference of the cylindrical frame.



Claims
  • 1. A fabric tensioning device for tensioning a fabric to be sewed in a stitch forming area of a sewing machine, said device comprising:a cylindrical frame having a sewing window and extending in the longitudinal direction; a core material clamping member for clamping down against said cylindrical frame a core material that covers said sewing window; and a fabric clamping member for clamping down against said cylindrical frame said core material and a fabric to be sewed that covers said core material, wherein said fabric clamping member opens and closes on said cylindrical frame, said core material clamping member comprises two core material clamping members formed oblong in the longitudinal direction, said core material clamping members provided on the left and right sides of said cylindrical frame respectively, and said two core material clamping members are mounted on said cylindrical frame to open and close independently.
  • 2. A fabric tensioning device of a sewing machine described in claim 1, whereinthe rear ends of said left and right side core material clamping members are affixed to the left and right sides of said cylindrical frame respectively, and the front ends of said left and right side core material clamping members open and close in the lateral direction.
  • 3. A fabric tensioning device of a sewing machine described in claim 1, further comprising:tighteners provided protrusively on the outer surface of said cylindrical frame, wherein said tighteners extend along the left and right edges of said sewing window and said core material clamping members are provided under said tighteners.
  • 4. A fabric tensioning device of a sewing machine described in claim 1, further comprising:clamps provided inside said core material clamping members at multiple locations along the longitudinal direction for making elastic contacts with said core material.
  • 5. A fabric tensioning device of a sewing machine described in claim 1, further comprising:temporary latches provided at the front end of said core material clamping members for engaging said cylindrical frame.
  • 6. A fabric tensioning device of a sewing machine described in claim 1, further comprising:two fabric clamps provided on each of the left and right sides of said fabric clamping member facing said core material clamping member from the outside; and a band that tightens said fabric clamping member and said core material clamping members against the cylindrical frame.
  • 7. A fabric tensioning device of a sewing machine described in claim 6, further comprising:slip guards made of processed fabric provided on the outer surface of said core material clamping members.
  • 8. A fabric tensioning device for tensioning a fabric to be sewed in a stitch forming area of a sewing machine, said device comprising:a cylindrical frame having a sewing window and extending in the longitudinal direction; two core material clamping members for clamping a core material against said cylindrical frame wherein said core material covers said sewing window; and a fabric clamping member for clamping down a fabric and said core material against said cylindrical frame wherein said fabric is to be sewed and covers said core material, wherein said fabric clamping member opens and closes on said cylindrical frame, said two core material clamping members formed oblong in the longitudinal direction, one of said two core material clamping members provided on a left side of said cylindrical frame and one of said two core material clamping members provided on the right side of said cylindrical frame, respectively, and said two core material clamping members open and close independent of each other.
  • 9. A method for tensioning fabric comprising the steps of:clamping down a core material against a cylindrical frame with one of two core material clamping members to secure said core material to one side of said cylindrical frame; adjusting a shape of a remaining portion of said core material to align said core material against the outer periphery of said cylindrical frame; and clamping down said core material against said cylindrical frame with the other core material clamping member to secure said core material to the other side of said cylindrical frame.
Priority Claims (1)
Number Date Country Kind
2002-137664 May 2002 JP
US Referenced Citations (5)
Number Name Date Kind
5553560 Tajima et al. Sep 1996 A
5701831 Morita Dec 1997 A
5915314 Moore, III Jun 1999 A
6170413 Hirose Jan 2001 B1
6279498 Hattori et al. Aug 2001 B1
Foreign Referenced Citations (1)
Number Date Country
WO 0053836 Sep 2000 WO