Trousers-fly-serging apparatus

Information

  • Patent Grant
  • 6237518
  • Patent Number
    6,237,518
  • Date Filed
    Thursday, August 12, 1999
    25 years ago
  • Date Issued
    Tuesday, May 29, 2001
    23 years ago
Abstract
In a trousers-fly-serging apparatus, a fly is fed on and along a feed table by a retaining portion of a linear supply section, and pressing levers attached to lower portions of four corners of a support body move down to press and retain the fed fly with tip ends of the pressing levers. Then, a rod actuated by a pressure cylinder is towed to rotate a rear portion of the support body about a pin as a pivot provided at a front end portion of the support body, so that one corner portion of a leading end portion of the fly is trimmed into an arcuate shape by a cutter and at the same time, the arcuately trimmed edge portion is serged by a needle. According to the apparatus, therefore, the one corner portion of the leading end of the fly can be trimmed into a uniform arcuate shape.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a trousersfly-serging apparatus and particularly to a rotary supply section for rotating a fly and trimming a corner portion of the fly into an arcuate shape and serging a longitudinal edge portion of the fly.




2. Description of the Related Art




As a rotary supply section in a conventional trousers-fly-serging apparatus, there are ones as disclosed in Japanese Patent Publication Laid-open No. 5-192471 and U.S. Pat. No. 5,161,474, for example. According to the apparatus of the Publications, a guide is formed continuously by bending a supply unit and a serging unit into a V shape so as to supply a fly to the serging unit from a diagonally rear direction, the fly is guided to abut on an angle of the guide, which projects toward a supply passage, and then the fly is fed forward for serging and rotated by towing a leading end portion of the fly, and a corner portion of the leading end portion of the fly is trimmed into an arcuate shape and at the same time, is serged. There is also a known rotary supply section as disclosed in Japanese Patent Publication Laid-open No. 5-137865 wherein a spherical cloth-pressing member is disposed at a position near a serging unit. The cloth-pressing member is moved down to press a portion of a supplied fly near a leading end portion and near a center on one side of the fly, and the leading end portion of the fly is towed by a pulling force by feeding of feed dogs actuated together with a needle to rotate the fly about a portion pressed by the spherical pressing member as a pivot, so that one corner portion of the leading end portion of the fly is trimmed into an arcuate shape, and at the same time, is serged.




In any of the conventional rotary supply sections, the fly is rotated by pulling the leading end portion of the fly by a pulling force of feeding of the feed dogs of the serging unit, and a pivot about which the fly rotates is a projecting angle of the guide or a point pressed by a spherical pressing member. Therefore, the towing force of the fly is liable to vary and the pivot about which the fly rotates is liable to be displaced.




As a result, the shape of the corner portion of the fly as trimmed varies, so that the uniform flies can not be necessarily obtained but irregular products are produced.




SUMMARY OF THE INVENTION




Therefore, it is an object of the present invention to provide a trousers-fly-serging apparatus in which the conventional problems are solved, one corner portion of a leading end portion of a fly can be constantly trimmed into a uniform arcuate shape, and a side end portion of the fly including the arcuate edge portion can be serged neatly.




To achieve the above object, according to the present invention, there is provided a trousers-fly-serging apparatus for supplying a trousers fly to a serging unit from a diagonally upstream direction and for rotating the supplied fly to trim one corner portion of a leading end portion of the fly into an arcuate shape, and at the same time, to serge the arcuate edge portion and one longitudinal edge portion of the fly, the apparatus comprising a supply portion of the fly including a linear supply section and a rotary supply section, wherein the rotary supply section includes a support body with a rear portion thereof being rotatable about a front end portion of the rotary supply section as a pivot, and several pressing levers are provided at a lower portion of the support body for upward and downward movements to press and retain the fly on a feed table, so that the fly fed from the linear supply section is received, and the rear portion of the support body is rotated to trim the one corner portion of the leading end portion of the fly into the arcuate shape and at the same time, to serge the arcuate edge portion and the one longitudinal edge portion of the fly.




Preferably, the support body of the rotary supply section is hung by a pin, which is rotatably supported by a support portion fixed to a proper position of the serging apparatus, is attached to the front end portion of the support body, and which functions as a rotation pivot. With this structure, a space for pressing and retaining the fly can be formed below the support body so that the fly can be easily disposed with the leading end portion thereof in contact with the serging unit.




Further preferably, the support body of the rotary supply section has, at a center of a rear portion thereof, a notch portion into which a retaining portion of the linear supply section for feeding the fly enters and fits. With this structure, four corners of the fly can be easily pressed and retained, and the pressed and retained fly can be positioned such that the leading end portion of the fly is constantly and accurately in contact with the serging unit.




Still further, it is preferable that each of the several pressing levers attached to the lower portion of the support body of the rotary supply section has, at a lower end thereof, a rotary roll rotatable only in a longitudinal direction of the fly. With this structure, the pressed and retained fly can be fed smoothly.




Still further, it is preferable that the support body of the rotary supply section includes a guide side wall hung from a lower portion of a longitudinal side portion of the support body. With this structure, the pressed and retained fly can be rotated while being pushed from a rear direction, and the fly can be fed accurately while being guided by the guide side wall.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a schematic plan view of an entire serging apparatus of the present invention.





FIG. 2

is a perspective view of a linear supply section and a rotary supply section.





FIG. 3

is a schematic plan view of an entire serging apparatus for supplying and processing a single fly piece.





FIG. 4

is a sectional view of a structure of the rotary supply section.





FIG. 5

is a sectional view of a structure of the linear supply section.





FIG. 6

is an explanatory view showing rotation of a support body of the rotary supply section in sequence and showing a state wherein the support body recieves the fly and starts rotating.





FIG. 7

is an explanatory view similar to

FIG. 7

but showing a state of serging of a longitudinal edge portion of the fly as the support body further rotates.





FIG. 8

is an explanatory view similar to

FIGS. 6 and 7

but showing a state wherein the support body has returned to its original position after the processing of the fly is finished.





FIG. 9

is a plan view of a processed fly product.





FIG. 10

is a plan view of another processed fly product.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Embodiments of the present invention will be now described below based on examples shown in the drawings.





FIG. 1

schematically shows an entire trousers-fly-serging apparatus.

FIGS. 2

,


4


, and


5


show respective structures of a supply unit for flies.

FIGS. 9 and 10

show flies processed by the present apparatus.




As shown in

FIG. 1

, the trousers-fly-serging apparatus comprises a supply unit


10


and a serging unit


50


for the fly


1


, supplies the fly


1


to the serging unit


50


from a diagonally rear direction, trims one corner portion


2


of a leading end portion of the fly


1


into an arcuate shape, and serges a longitudinal edge portion


3


of the fly


1


including the arcuate edge by using a sewing machine to avoid raveling of cloth of the fly


1


and to make the fly


1


good in appearance.




The supply unit


10


for the fly


1


comprises a linear supply section


11


and a rotary supply section


30


and is diagonally connected to the serging unit


50


as shown in FIG.


1


. The linear supply section


11


receives the fly


1


supplied from a supply device


12


connected to the serging apparatus, supplies the fly


1


to the next rotary supply section


30


. The linear supply section


11


comprises a retaining portion


11




a


and a carriage portion


11




b


for reciprocating the retaining portion


11




a


. As shown in

FIGS. 2 and 5

, the retaining portion


11




a


comprises pressing levers


13


and a pressure cylinder


16


for actuating the pressing levers


13


. At least two front and rear pressing levers


13


are attached to an attaching frame


15


and head portions


14


of the pressing levers


13


are loosely received by a support plate


17


. A compression spring


18


is fitted around an intermediate portion of each of the pressing levers


13


between the attaching frame


15


and the support plate


17


and normally pushes the pressing lever


13


downward. The pressure cylinder


16


is attached to the support plate


17


and a rod


20


of the pressure cylinder


16


is connected to the attaching frame


15


and moves up and down by pressure. Thus, the fly


1


formed by cutting a continuous fly into a constant length and supplied from the supply device


12


is retained from above by the two pressing levers


13


and is released. A hanging arm


21


is attached to a side of the support plate


17


to which the pressure cylinder


16


is attached for actuating the attaching frame


15


and is hung on an endless belt


23


provided on one side of a feed table


22


. The carriage portion


11




b


comprises the endless belt


23


and a driving shaft


24


for actuating the endless belt


23


. The endless belt


23


bridges a pair of rotary shafts along a side of the feed table


22


. One of the rotary shafts is the driving shaft


24


and the endless belt


23


is rotated in normal and reverse directions by rotation of the driving shaft


24


so as to feed or move the linear supply section


11


toward or away from the next rotary supply section


30


. A long fly


1




a


supplied to the supply device


12


connected to a rear portion of the present apparatus is fed off by a supply roller


25


and cut into a predetermined length by a cutting blade


26


to be a single fly piece


1


and fed onto the feed table


22


. Then, the pressing levers


13


standing by at predetermined positions above the fly


1


move down by actuation of the pressure cylinder


16


to press a surface of the fly


1


and to retain the fly


1


between the pressing levers


13


and a surface of the feed table


22


, as shown by dashed lines in FIG.


5


. The fly


1


is pierced by projections


27


provided to lower portions


19


of the respective pressing levers


13


so that it can be reliably fed on the feed table


22


. The endless belt


23


is rotated to feed the fly


1


to the downstream rotary supply section


30


in a state wherein the pressing levers


13


have moved down to press and retain the fly


1


. When feeding of the fly


1


has been completed and the fly


1


has been pressed and retained by the rotary supply section


30


which will be described later, the pressure cylinder


16


on the support plate


17


is actuated to pull the rod


20


upward and moves the two pressing levers


13


attached to the attaching frame


15


up to positions as shown by solid lines in

FIG. 5

, thereby releasing the fly


1


. Thereafter, the endless belt


23


is rotated in a reverse direction to return the retaining portion


11




a


of the linear supply section


11


to the initial position and to bring the retaining portion


11




a


into a standby position for feeding of the succeeding fly


1


. By repeating such operations, the fly


1


is fed to the next rotary supply section


30


.




The long fly


1




a


is fed by the supply roller


25


by a predetermined length to be cut by the cutting blade


26


to be a single fly piece


1


, which is supplied to the linear supply section


11


in the embodiment shown in FIG.


1


. When a slide fastener chain


8


is sewn on the long fly


1




a


, space portions of the slide fastener chain


8


, which are provided at constant intervals and where engaging elements are not attached, are detected, and the fly


1




a


is cut at the space portions to be single fly pieces


1


and fed to the linear supply section


11


. Further, in a case of a fly


1




b


to which a slide fastener chain


4


is diagonally sewn and when the fly is not only a long fly but is a cut fly piece with a predetermined length, the single fly piece


1




b


is supplied one by one to the linear supply section


11


as shown in FIG.


3


.




The rotary supply section


30


is arranged on an extension of the linear supply section


11


at a downstream side thereof. The rotary supply section


30


receives the fly


1


fed by the retaining portion


11




a


of the linear supply section


11


, and reliably presses and retains the fly


1


. Then, a rear portion of the rotary supply section


30


is towed to rotate the fly


1


together with the rotary supply section


30


about a front end portion of the rotary supply section


30


as a pivot. As a result, one corner portion


2


of a leading end portion of the fly


1


is trimmed by a cutter


4


into a constant arcuate shape, and at the same time, the corner edge portion of the fly


1


is serged by a needle


5


. While a longitudinal edge portion


3


of the fly


1


is serged , the fly


1


is retained by the rotary supply section


30


, thereby constantly obtaining uniformly processed products.





FIGS. 2 and 4

show a structure of the rotary supply section


30


. A support body


32


, at a lower face of which pressing levers


31


are attached for pressing and retaining the fly


1


, has a pin


37


at its front end portion as shown in FIG.


2


. The support body


32


is hung by the pin


37


of which upper portion is rotatably inserted in and supported by a support portion


44


fixed to a proper position (not shown) of the serging apparatus. Thus, a space is formed below the support body


32


such that the supplied fly


1


can be disposed, pressed, and retained with the leading end portion of the fly


1


in contact with the serging unit


50


. Further, a notch portion


33


is formed at a center of a rear portion of the support body


32


so that the attaching frame


15


of the pressing levers


13


of the retaining portion


11




a


of the linear supply section


11


for feeding the fly


1


can enter and fit into the notch portion


33


from a rear direction as shown by dashed lines in FIG.


6


. As a result, the rotary supply section


30


can press and retain the fly


1


in a wide range including the front and rear portions of the fly


1


and can position the fly


1


such that the leading end portion of the fly


1


is always positioned at a position of the needle


5


of the serging unit


50


. At positions corresponding to four corners of the support body


32


, four pressing levers


31


for pressing and retaining the fly


1


are disposed on a lower face of the support body


32


, respectively. The four pressing levers


31


are attached to a single attaching frame


34


, and the fly


1


on the feed table


22


is pressed and released by moving up and down the attaching frame


34


. The pressing levers


31


are loosely received by the support body


32


, and their adjusting nuts


35


are respectively fitted on head portions of the pressing levers


31


so as to adjust lengths of the pressing levers


31


projecting downward. Rotary rolls


36


are respectively attached to lower ends of the pressing levers


31


so as to rotatably press and retain the fly


1


by lowering of the pressing levers


31


and to move the fly


1


only in a longitudinal direction of the fly


1


, as shown by dashed lines in FIG.


4


. One of the pressing levers


31




a


at the front end portion of the support body


32


is disposed forward of the pin


37


as a pivot of rotation of the support body


32


which will be described later and presses the leading end portion of the fly


1


at the forward position so as to prevent displacement of the leading end portion of the fly


1


due to the rotation. A pressure cylinder


38


for moving up and down the attaching frame


34


of the pressing levers


31


is attached to a center of a side portion of the support body


32


and actuates the attaching frame


34


upward and downward by a rod


39


. Further, two guide pins


40


attached to the attaching frame


34


are loosely received in the support body


32


, and head portions of the guide pins


40


are projecting upward. As shown in

FIG. 6

, an elongated hole


41


extending in the longitudinal direction is defined at a side portion of a rear end of the support body


32


, and a tip end of a rod


42


for rotating the support body


32


is loosely received in the elongated hole


41


. This rod


42


is towed and extended by actuation of a pressure cylinder


43


rotatably attached to a rear end portion of the rod


42


at a side end of the feed table


22


as shown in FIG.


1


. By the tow and extension of the rod


42


, the support body


32


rotates about the pin


37


attached to the front end portion of the support body


32


as a pivot, from a receiving position of the fly


1


shown in

FIG. 6

to a position for serging a longitudinal edge portion


3


of the fly


1


shown in

FIG. 7

, during which time the rear end portion of the support body


32


rotates so as to rotate the leading end portion of the fly


1


and to trim the one corner portion


2


of the fly


1


into an arcuate shape, and at the same time to serge the corner portion


2


. Then, after feeding off the fly


1


, the rear portion of the support body


32


rotates back for receiving and processing the succeeding fly


1


as shown in FIG.


8


. A side wall


45


, which extends down to reach a position close to the surface of the feed table


22


, is provided at a side portion of the support body


32


as shown in

FIGS. 2 and 4

, retains and pushes the fly


1


sideways in rotation of the support body


32


, and also regulates and guides a side of the fly


1


which is fed in serging of the longitudinal edge portion


3


of the fly


1


as shown in

FIG. 7

so as to neatly carry out the serging.




The pin


37


is fastened at its positions above and below the support portion


44


by nuts as shown in

FIG. 2

so that a position of the pin


37


is adjustable in a vertical direction. As a result, it is possible to adjust the position of the support body


32


such that a lower end face of the side wall


45


which is hung from the support body


32


keeps a distance equal to or smaller than a thickness of the fly


1


from an upper face of the feed table


22


, which does not hinder rotation of the rotary supply section


30


.




The serging unit


50


has a structure similar to a conventional serging machine, and carries out serging by the needle


5


which moves up and down while pressing the fly


1


with a presser foot


7


, and feeds off the fly


1


by feed dogs


6


for every stitch at the same time. The serging unit


50


is displaced from the pin


37


which is the pivot about which the rotary supply section


30


rotates, as shown in

FIG. 7

, so as to serge an edge portion of the fly


1


from a center of its leading end portion to its one longitudinal edge portion


3


. A cutter


4


is provided on a side of the presser foot


7


so as to trim the edge portion of the fly


1


to be serged synchronously with the movement of the needle


5


. After trimming and at the same time serging of the edge portion of the leading end portion of the fly


1


in the serging unit


50


, the fly


1


is fed off to a discharge table


51


as a product as shown in

FIG. 9

or


10


.





FIG. 6

shows a state wherein the fly


1


has been supplied from the linear supply section


11


to the rotary supply section


30


, its leading end portion of the fly


1


is positioned so as to face the needle


5


of the serging unit


50


, and the serging starts simultaneously with the trimming. The rear portion of the rotary supply section


30


rotates about the pin


37


as the pivot by the tow of the rod


42


. As the rear portion of the rotary supply section


30


rotates, the fly


1


is rotated and the one corner portion


2


of the leading end portion of the fly


1


rotates arcuately to pass on the cutter


4


, thereby trimming the corner portion


2


into the arcuate shape. Then, the trimmed edge portion is serged by the needle


5


. The rotary supply section


30


rotates to a position where the rotary supply section


30


is arranged in line with the serging unit


50


and stops there as shown in FIG.


7


. Then, the longitudinal edge portion


3


of the fly


1


is serged by the needle


5


successively after serging of the corner portion


2


and at the same time, the fly


1


is fed off by the feed dogs


6


one after another onto the discharge table


51


as the sergedfly


1


,


1




b


as shown in

FIG. 9

or


10


. Then, the rotary supply section


30


rotates in a reverse direction by extension of the rod


42


and returns to its original position and stand by for receiving the succeeding fly


1


. By repeating such operations, the flies


1


are processed and finished in sequence.




According to the present apparatus, it is possible to process, for example, a long fly


1




a


to which a long slide fastener chain is sewn longitudinally, or a single fly piece


1


formed by cutting a long fly, to which the slide fastener chain is not sewn, into a predetermined length, or a fly


1




b


formed by diagonally sewing a slide fastener chain


8


with a predetermined length to a long fly and cutting the long fly into a predetermined length as shown in FIG.


10


. It is also possible to similarly process a single fly piece having a corner portion which is trimmed slightly into an arcuate shape in advance by an amount smaller than the predetermined trimming amount as shown in

FIG. 3

so that front and back face sides of the fly or a supply direction of the fly can be distinguished.




According to the present apparatus, the four corners of the fly


1


are pressed and retained by the rotary supply section


30


, and then the fly


1


is rotated by rotating the rotary supply section


30


which is pressing and retaining the fly


1


about the pivot which can not be displaced, and the one corner portion


2


of the leading end portion of the fly


1


is trimmed into an arcuate shape and at the same time, the fly


1


is serged. As a result, the fly


1


is retained and rotated in a constant state. Further, because the pivot of the rotation is not displaced, the trimmed shape of the one corner portion


2


of the leading end portion of the fly


1


is made in a constant arcuate shape. Thus, after the edge portion is serged, the uniform products can be obtained.




According to the present invention which has the above-described structures, the fly


1


fed from the linear supply section


11


is pressed and retained by several pressing levers


31


attached to the support body


32


of the rotary supply section


30


, and the fly


1


is rotated by rotating the rear portion of the support body


32


about the front end portion of the support body


32


as a pivot to trim the one corner portion


2


of the leading end portion of the fly


1


into an arcuate shape, and at the same time, to serge the one longitudinal edge portion of the fly including the corner edge portion


2


. Therefore, because the fly


1


is rotated and supplied to the serging unit


50


in a constant state, it is possible to constantly trim the one corner portion


2


of the leading end portion of the fly


1


into a constant arcuate shape, thus the uniform products can be obtained after the edge portion is serged.




Further, the support body


32


of the rotary supply section


30


is hung by attaching the pin


37


to the front end portion of the support body


32


and rotatably supporting the pin


37


by the support portion


44


fixed to a proper position of the serging apparatus. Therefore, a space can be formed below the support body


32


so that the fly


1


can be easily disposed such that the leading end portion of the fly


1


is in contact with the needle


5


, the cutter


4


, and the other members of the serging unit


50


.




Furthermore, the support body


32


of the rotary supply section


30


has, at the center of the rear portion thereof, the notch portion


33


into which the attaching frame


15


of the pressing levers


13


of the linear supply section


11


enters and fits. Because the four corners of the fed fly


1


can be pressed and retained, the fly


1


can be further reliably retained, and the fly


1


is not displaced even when the fly


1


is rotated so that the fly


1


can be supplied to the serging unit


50


in a constant state. Moreover, because the retaining portion


11




a


of the linear supply section


11


, which has fed the fly


1


while retaining it, can be stopped at a constant position by the notch portion


33


to pass the fly


1


to the serging unit


50


, the fly


1


can be positioned at a constant position with respect to the serging unit


50


.




Still further, the several pressing levers


31


attached to the lower portion of the support body


32


of the rotary supply section


30


has, at lower ends thereof, the rotary rolls


36


rotatable only in the longitudinal direction of the fly


1


. Therefore, the fly


1


can be smoothly fed off from the support body


32


in serging of the one longitudinal edge portion


3


of the fly


1


, so that uniform stitches of the serging can be obtained.




Still further, the support body


32


of the rotary supply section


30


includes the guide side wall


45


provided at the lower portion of one longitudinal side portion of the support body


32


. Therefore, the fly


1


is rotated while being pushed at its longitudinal edge portion sideways, the fly


1


can be further reliably rotated and fed, so that the constant trimming of the corner portion


2


of the fly


1


into a constant arcuate shape can be ensured. Moreover, because the guide side wall


45


guides the longitudinal edge portion of the fly


1


during serging of the other longitudinal edge portion


3


of the fly


1


to feed off the fly


1


straightly, the lontigudinal edge portion


3


of the fly


1


can be serged neaatly.



Claims
  • 1. A trousers-fly-serging apparatus for supplying a trousers fly to a serging unit from a diagonally upstream direction and for rotating the supplied fly to trim one comer portion of a leading end portion of the fly into an arcuate shape, and at the same time, to serge the arcuate edge portion and one longitudinal edge portion of the fly, the apparatus comprising a supply portion of the fly including a linear supply section and a rotary supply section,wherein the rotary supply section includes a support body with a rear portion thereof being rotatable about a front end portion of the rotary supply section as a pivot, and wherein the support body of the rotary supply section has, at a center of a rear portion thereof, a notch portion into which a retaining portion of the linear supply section for feeding the fly enters and fits, and several pressing levers are provided at a lower portion of the support body for upward and downward movements to press and retain the fly on a feed table, so that the fly fed from the linear supply section is received, and the rear portion of the support body is rotated to trim the one comer portion of the leading end portion of the fly into the arcuate shape and at the same time, to serge the arcuate edge portion and the one longitudinal edge portion of the fly.
  • 2. A trousers-fly-serging apparatus for supplying a trousers fly to a serging unit from a diagonally upstream direction and for rotating the supplied fly to trim one comer portion of a leading end portion of the fly into an arcuate shape, and at the same time, to serge the arcuate edge portion and one longitudinal edge portion of the fly, the apparatus comprising a supply portion of the fly including a linear supply section and a rotary supply section,wherein the rotary supply section includes a support body with a rear portion thereof being rotatable about a front end portion of the rotary supply section as a pivot, and several pressing levers are provided at a lower portion of the support body for upward and downward movements to press and retain the fly on a feed table, so that the fly fed from the linear supply section is received, and wherein each of the several pressing levers attached to the lower portion of the support body of the rotary supply section has, at a lower end thereof, a rotary roll rotatable only in a longitudinal direction of the fly, and the rear portion of the support body is rotated to trim the one comer portion of the leading end portion of the fly into the arcuate shape and at the same time, to serge the arcuate edge portion and the one longitudinal edge portion of the fly.
  • 3. A trousers-fly-serging apparatus according to claim 1 or 2, wherein the support body of the rotary supply section is hung by a pin, the pin being rotatably supported by a support portion fixed to a certain position of the serging apparatus, being attached to the front end portion of the support body, and functioning as a rotation pivot.
  • 4. A trousers-fly-serging apparatus according to claim 1 or 2, wherein the support body of the rotary supply section includes a guide side wall extended from a lower portion of a longitudinal side portion of the support body.
Priority Claims (1)
Number Date Country Kind
10-284706 Aug 1998 JP
US Referenced Citations (4)
Number Name Date Kind
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