METHOD OF AND APPARATUS FOR AUTOMATIC BAG REVERSING
United States Patent 3779432
This invention consists of clamping both ends of a bag with a pair of clamps each composed of two clamping plates for holding the respective ends of the bag between them from the inside and outside of the bag and rotating the pair of clamps in their respective inward directions with their clamping plates holding the ends of the bag between them so that the bag is turned inside out and outside in.
US Patent References:
Apparatus for everting pocket-like workpieces
Oberrecht - December 1967 - 3357609
Glove finishing machine
Beasley - June 1958 - 2838216
Bag machine
Koppel - September 1940 - 2214502
Apparatus for everting pocket-like workpieces
Oberrecht - December 1967 - 3357609
Glove finishing machine
Beasley - June 1958 - 2838216
Bag machine
Koppel - September 1940 - 2214502
Inventors:
Fukuta, Kenji (Yokohama, JA)
Sekiguchi, Junichi (Yokohama, JA)
Miyashita, Rihei (Yokohama, JA)
Matsuzaki, Yoshihira (Chigasaki-shi, JA)
Miura, Yoshihiro (Yokosuka-shi, JA)
Sekiguchi, Junichi (Yokohama, JA)
Miyashita, Rihei (Yokohama, JA)
Matsuzaki, Yoshihira (Chigasaki-shi, JA)
Miura, Yoshihiro (Yokosuka-shi, JA)
Application Number:
05/192459
Publication Date:
12/18/1973
Filing Date:
10/26/1971
View Patent Images:
Export Citation:
Assignee:
Agency of Industrial Science & Technology (Tokyo, JA)
Primary Class:
International Classes:
D06G3/02; D06G3/00; A41H43/00
Field of Search:
223/39-43
Primary Examiner:
Larkin, George V.
Claims:
We claim
1. A method for everting a bag which comprises inserting a pair of clamps along respective ends of the bag, said clamps each composed of two clamping plates disposed for holding respective ends of the bag therebetween, clamping one clamping plate of each pair disposed within the bag and the other clamping plate disposed outside the bag, rotating the pair of clamps while in bag clamping position while diminishing the distance between the pair of clamps during everting of the bag, in the extended plane of the bag and to everting position through points of nearest proximity of the clamps until the bag is stretched to full everted length, and releasing said clamping of an everted bag.
2. An apparatus for everting a bag which comprises in combination, a pair of clamps, said clamps each having two clamping plates disposed for holding respective ends of a bag therebetween with one clamping plate of each pair disposed within the bag and the other clamping plate disposed outside the bag, rotating means for rotating each of said clamps while in bag holding position in the extended plane of the bag and to everting position through points of nearest proximity of the clamps until the bag is stretched to full everted length, means for diminishing the distance between said clamps during rotation, and means for opening said clamps and for releasing the bag after everting is effected.
1. A method for everting a bag which comprises inserting a pair of clamps along respective ends of the bag, said clamps each composed of two clamping plates disposed for holding respective ends of the bag therebetween, clamping one clamping plate of each pair disposed within the bag and the other clamping plate disposed outside the bag, rotating the pair of clamps while in bag clamping position while diminishing the distance between the pair of clamps during everting of the bag, in the extended plane of the bag and to everting position through points of nearest proximity of the clamps until the bag is stretched to full everted length, and releasing said clamping of an everted bag.
2. An apparatus for everting a bag which comprises in combination, a pair of clamps, said clamps each having two clamping plates disposed for holding respective ends of a bag therebetween with one clamping plate of each pair disposed within the bag and the other clamping plate disposed outside the bag, rotating means for rotating each of said clamps while in bag holding position in the extended plane of the bag and to everting position through points of nearest proximity of the clamps until the bag is stretched to full everted length, means for diminishing the distance between said clamps during rotation, and means for opening said clamps and for releasing the bag after everting is effected.
Description:
The present invention relates to a method of and an apparatus for turning a bag inside out automatically.
The term "bag" as used in this specification means any bag like article made of two sheets of cloth, paper, film or other flexible material which are generally put together and sewn or joined at three sides with one side open or at two opposing sides with the other two opposing sides open to make a tubular form.
In the method of making a bag having the simplest rectangular form, at least two sheets of the same form are placed one upon the other and sewn or joined together at three sides to make them into a bag form. The bag thus formed is pushed or pulled out of itself, i.e., everted, by turning its inside out and its outside in at the same time through the open part of the edge remaining unsewn, i.e., the opening edge. This reversing operation i.e., everting, intended for hiding the seam or joint of a bag in its inside for better appearance is being widely used in making cuffs or collars in the sewing process of drape shirts etc. or in producing bag-like containers of synthetic high-molecular materials.
This reversing or everting operation is a complicated combination of such basic operations as clamping, deformation, moving and rotation, and has therefore been found difficult to mechanically automate and heretofore has been carried out manually especially where the material of the bag is highly flexible or locally different in the degree of flexibility.
The main object of this invention is to provide an apparatus for automatic reversing of a bag, by which industries producing sewn products as well as other industries can make remarkable progress toward automation.
Additional objects and advantages of the present invention will become apparent as the description proceeds in connection with the accompanying drawings in which:
FIGS. 1-5 are diagrams illustrating the sequence of the process of this invention;
FIG. 6 is a perspective view of the main parts of an apparatus used for carrying out the method of this invention;
FIG. 7 is a sectional view of the apparatus shown in FIG. 6;
FIG. 8 is a plan view of the apparatus shown in FIG. 6;
FIG. 9 is a sectional view of the main parts of another apparatus used for executing the present invention;
FIG. 10 is a diagram illustrating an apparatus of this invention provided with auxiliary plates;
FIG. 11 is a plan of an apparatus used for carrying out the pretreating process of this invention; and
FIG. 12 is a sectional view taken along line VIII--VIII of FIG. 11.
FIGS. 1-5 are diagrams sequentially illustrating the steps of the reversing operation of a cuff as an example. Usually a cuff is made up of a sheet of padding and two sheets of base cloth placed upon the padding one upon the other, all these sheets being sewn together at three edges. When the cuff is reversed, the padding is sandwiched by the base cloth on both sides, so that the reversing operation is the same as that for reversing a bag made up of two sheets of base cloth.
Referring back to FIG. 1, the cuff 1 is fed by a suitable apparatus (not shown) with its opening edge facing a pair of clamps 2. Said pair of clamps 2 each consists of two clamping plates 3 and 4 each rotating independently on the axis 5, the distance between said clamps being suitably adjusted depending on the size of cuff 1 to be everted.
When each plate 3 is inserted near its end of the opening edge of cuff 1, it holds the cuff 1 by tightening through rotation, each plate 4 rotates oppositely to the rotation of said plate 3 so that the both ends of the cuff 1 are held from the inside and outside as shown in FIG. 2. Next, as shown in FIG. 3 the clamps 2 rotate toward their point of nearest proximity in the inward direction while still holding the cuff as the distance between the axes of the two clamps 2 is reduced until the clamps pass the point of nearest proximity and the cuff 1 is again tightened. After making a rotation of about 180°, each clamp 2 recovers the original interaxial distance, thus completing the reversing operation of the cuff 1 as shown in FIG. 4.
The cuff 1 thus reversed is released from the clamps 2 by the respective reverse operations of plates 2 and 3 and is then transferred to the following step of the process by a suitable means (not shown).
The automatic bag reversing operation of this invention as stated above consists of clamping the bag held in a state ready for reversing by means of the two clamping plates of the pair of clamps located at the right and left and, in the order shown in FIG. 1 to FIG. 5, reversing the bag by the respective inward rotations of the clamps with the bag held by them, releasing the bag thereafter from the clamps to complete the operation and rotating the clamps again to become ready for receiving the feed of the next bag. Automatic reversing of bags is effected by repeating this operation. An embodiment of the apparatus of this invention will be described below in detail by referring to FIG. 6 and FIG. 7.
In the figures, the pair of clamps 2 for clamping the bag 1 to be reversed ar mounted to the frame with a specified distance between them as stated above, said distance being preliminarily adjusted depending upon the size of the bag to be reversed.
The clamping plates 3 and 4 made of a suitable material such as metal or plastic are fitted to the circumference of the center supporting shaft 5 through arms 6 and 7 and shafts 8 and 9 respectively so that they can rotate independently. To the lower part of said supporting shaft 5 is fitted a rotating disk 10 forming a gear along its circumference and having a spindle 11 on its lower face, said spindle 11 being supported rotatably by a slider 12. The slider 12 is fitted in the long hole 14 provided in the frame 13 and is fixed at a predetermined position by a rack 15 engaging with the gear formed along the circumference of the rotating disk 10.
The rotating disk 10 is provided with two motors 17 and 18, motor 17 rotating the shaft 8 through the gears 19 and 20 and the magnetic clutch 21 and thus rotating clamping plate 3 about the shaft 5 and motor 18 rotating shaft 9 through the gears 23 and 24 and the magnetic clutch 25 and thus rotating the clamping plate 4 about the shaft 5. Said plates 3 and 4 are made to rotate in either direction by appropriately changing the polarity of the voltage applied to motors 17, 18. The plates are made to stop by means of the clutches.
When the clamping plate 3 is inserted near the opening edge of a bag fed by a suitable method, the clamping plate 3 moves to the end of the bag by the rotation of the motor 17 and holds the bag so as to tighten it, while at the same time the clamping plate 4 is rotated oppositely to the rotation of the plate 3 by the rotation of the motor 18 and both ends of the bag are thus held from the inside and outside between plates 7 and plates 4 as is shown in FIG. 3.
The two clamps 3 and 4 now holding the bar are made to rotate in the inward direction by the motion of the reciprocating rack 15 engaging the periphery of the rotating disk 10 and the bag reversing operation is thus effected. The face on that side of the rack which forms the teeth is slightly concaved and the gear provided along the periphery of the rotating disk is kept in constant engagement with the rack by the spring 16 provided on the slider. Thus, when the rotating disk comes to the concave portion of the rack, it is drawn inwardly by spring 16 so that the two clamps approach one another while they are rotating. The space between them is thereby reduced to allow for the deformation of the bag, thus ensuring perfect reversing of the bag.
After the clamps have made about a 180-degree rotation to complete the reversing operation, they return to their original position, recover the original distance between them, and thus complete one cycle of the bag reversing operation.
In the aforementioned embodiment, the two clamping plates 3 and 4 rotate in directions opposite to each other to hold the bag. As shown in FIG. 9, however, it is also possible to hold the bag from the outside by rotating the eccentric cam 26 provided at the lower part of the shaft 9 which connects with plate 4 and lifting the plate 4 to the same level as the plate 3 after plate 3 has been inserted in the bag to hold it in a tightened state. The clamps holding the bag in this way rotate in the inward direction because of the rack as described above and therefore they turn the bag inside out.
Although motors are used as means for rotating the clamping plates in this embodiment, other suitable means such as hydraulic or pneumatic systems can of course be used instead. The clamping plate 4 may be installed at a position higher than the clamping plate 3 and pushed down to a position level with the plate 3 by hydraulic, pneumatic or other such suitable means.
Further as shown in FIG. 10, the clamping plates 3 and 4 may be provided with auxiliary plates 27 above and below them. When the bag is passed between the clamping plates and the auxiliary plates while the bag is being reversed, the auxiliary plates serve to impart a specified amount of resistance to the passing bag to control the unwanted motion during everting and also to correct any imperfectly everted portion. Thus, the everting operation is made more efficient and perfect. It is further possible to provide the auxiliary plates with heat sources for improving the finish of the everted bag by hot-pressing the clamping plates on both sides with the auxiliary plates 27 after the reversing operation has been completed.
In case the two sheets of cloth or film composing the bag to be reversed are equal in flexibility, the bag is bent along the seam line and reversed uniformly in the reversing and post-treating operations. But if padding is attached to one of the sheets as in the case of a cuff or collar in particular, the bag sometimes is not bent along the seam line because the two sheets are different in flexibility.
In such a case it may be impossible to reverse the bag along the seam line. In order to prevent this inconvenience, the bag is given a crease along the seam line by means of a press or the like for easier bending. This pre-treatment will be described below with regard to a cuff creased by a device of an embodiment shown in FIGS. 11 and 12.
The cuff is placed with its padding up on the press base 29 supported by the support 20. Said press base 29 is provided with the press 28 above it. The press 28 which is made of a hard material such as metal has a suitable interior heating means and is of a shape similar to the seam line of the cuff placed on the press base and either has an acute-angled edge for effective creasing or is provided on its surface with a protrusion having the same shape as the seam line. The press base on which the cuff is placed is made of a heat resisting and elastic material like silicon rubber, and its hardness, thickness, etc. are suitably selected according to the material to be creased. The support for the press base is made of a material hard enough to remain unbent when the pressure is applied.
To describe the process in detail, a plurality of pieces to be creased are arranged on the press base and pressed by lowering a heated press on them. The heating temperature and pressure of the press are suitably selected according to the material of the pieces. For example, polyester bags are pressed preferably at a pressure of about 2 - 5 kg/cm 2 at 150° - 180° C. Since the press is of the same shape or has a protrusion of the same shape as the seam line of each of the pieces and the press base is made of an elastic material, the pressed portion sinks in the press base and the periphery of the remaining unpressed portion rises along the press to leave a crease on the boundary, provided the pressure is applied to the parts uniformly by the press. After the pieces have been creased sufficiently, the press is released and the parts are fed to the reversing apparatus.
If said pre-treatment is given, even bags made up of base cloths of different flexibility can be readily reversed on their seam lines.
The use of the method and apparatus of this invention in the reversing processes of the sewn products manufacturing and other industries can raise the efficientcy of production and make up the shortage of labor as they automate the reversing of bags and baglike articles which have so far been done mostly by hand.
The term "bag" as used in this specification means any bag like article made of two sheets of cloth, paper, film or other flexible material which are generally put together and sewn or joined at three sides with one side open or at two opposing sides with the other two opposing sides open to make a tubular form.
In the method of making a bag having the simplest rectangular form, at least two sheets of the same form are placed one upon the other and sewn or joined together at three sides to make them into a bag form. The bag thus formed is pushed or pulled out of itself, i.e., everted, by turning its inside out and its outside in at the same time through the open part of the edge remaining unsewn, i.e., the opening edge. This reversing operation i.e., everting, intended for hiding the seam or joint of a bag in its inside for better appearance is being widely used in making cuffs or collars in the sewing process of drape shirts etc. or in producing bag-like containers of synthetic high-molecular materials.
This reversing or everting operation is a complicated combination of such basic operations as clamping, deformation, moving and rotation, and has therefore been found difficult to mechanically automate and heretofore has been carried out manually especially where the material of the bag is highly flexible or locally different in the degree of flexibility.
The main object of this invention is to provide an apparatus for automatic reversing of a bag, by which industries producing sewn products as well as other industries can make remarkable progress toward automation.
Additional objects and advantages of the present invention will become apparent as the description proceeds in connection with the accompanying drawings in which:
FIGS. 1-5 are diagrams illustrating the sequence of the process of this invention;
FIG. 6 is a perspective view of the main parts of an apparatus used for carrying out the method of this invention;
FIG. 7 is a sectional view of the apparatus shown in FIG. 6;
FIG. 8 is a plan view of the apparatus shown in FIG. 6;
FIG. 9 is a sectional view of the main parts of another apparatus used for executing the present invention;
FIG. 10 is a diagram illustrating an apparatus of this invention provided with auxiliary plates;
FIG. 11 is a plan of an apparatus used for carrying out the pretreating process of this invention; and
FIG. 12 is a sectional view taken along line VIII--VIII of FIG. 11.
FIGS. 1-5 are diagrams sequentially illustrating the steps of the reversing operation of a cuff as an example. Usually a cuff is made up of a sheet of padding and two sheets of base cloth placed upon the padding one upon the other, all these sheets being sewn together at three edges. When the cuff is reversed, the padding is sandwiched by the base cloth on both sides, so that the reversing operation is the same as that for reversing a bag made up of two sheets of base cloth.
Referring back to FIG. 1, the cuff 1 is fed by a suitable apparatus (not shown) with its opening edge facing a pair of clamps 2. Said pair of clamps 2 each consists of two clamping plates 3 and 4 each rotating independently on the axis 5, the distance between said clamps being suitably adjusted depending on the size of cuff 1 to be everted.
When each plate 3 is inserted near its end of the opening edge of cuff 1, it holds the cuff 1 by tightening through rotation, each plate 4 rotates oppositely to the rotation of said plate 3 so that the both ends of the cuff 1 are held from the inside and outside as shown in FIG. 2. Next, as shown in FIG. 3 the clamps 2 rotate toward their point of nearest proximity in the inward direction while still holding the cuff as the distance between the axes of the two clamps 2 is reduced until the clamps pass the point of nearest proximity and the cuff 1 is again tightened. After making a rotation of about 180°, each clamp 2 recovers the original interaxial distance, thus completing the reversing operation of the cuff 1 as shown in FIG. 4.
The cuff 1 thus reversed is released from the clamps 2 by the respective reverse operations of plates 2 and 3 and is then transferred to the following step of the process by a suitable means (not shown).
The automatic bag reversing operation of this invention as stated above consists of clamping the bag held in a state ready for reversing by means of the two clamping plates of the pair of clamps located at the right and left and, in the order shown in FIG. 1 to FIG. 5, reversing the bag by the respective inward rotations of the clamps with the bag held by them, releasing the bag thereafter from the clamps to complete the operation and rotating the clamps again to become ready for receiving the feed of the next bag. Automatic reversing of bags is effected by repeating this operation. An embodiment of the apparatus of this invention will be described below in detail by referring to FIG. 6 and FIG. 7.
In the figures, the pair of clamps 2 for clamping the bag 1 to be reversed ar mounted to the frame with a specified distance between them as stated above, said distance being preliminarily adjusted depending upon the size of the bag to be reversed.
The clamping plates 3 and 4 made of a suitable material such as metal or plastic are fitted to the circumference of the center supporting shaft 5 through arms 6 and 7 and shafts 8 and 9 respectively so that they can rotate independently. To the lower part of said supporting shaft 5 is fitted a rotating disk 10 forming a gear along its circumference and having a spindle 11 on its lower face, said spindle 11 being supported rotatably by a slider 12. The slider 12 is fitted in the long hole 14 provided in the frame 13 and is fixed at a predetermined position by a rack 15 engaging with the gear formed along the circumference of the rotating disk 10.
The rotating disk 10 is provided with two motors 17 and 18, motor 17 rotating the shaft 8 through the gears 19 and 20 and the magnetic clutch 21 and thus rotating clamping plate 3 about the shaft 5 and motor 18 rotating shaft 9 through the gears 23 and 24 and the magnetic clutch 25 and thus rotating the clamping plate 4 about the shaft 5. Said plates 3 and 4 are made to rotate in either direction by appropriately changing the polarity of the voltage applied to motors 17, 18. The plates are made to stop by means of the clutches.
When the clamping plate 3 is inserted near the opening edge of a bag fed by a suitable method, the clamping plate 3 moves to the end of the bag by the rotation of the motor 17 and holds the bag so as to tighten it, while at the same time the clamping plate 4 is rotated oppositely to the rotation of the plate 3 by the rotation of the motor 18 and both ends of the bag are thus held from the inside and outside between plates 7 and plates 4 as is shown in FIG. 3.
The two clamps 3 and 4 now holding the bar are made to rotate in the inward direction by the motion of the reciprocating rack 15 engaging the periphery of the rotating disk 10 and the bag reversing operation is thus effected. The face on that side of the rack which forms the teeth is slightly concaved and the gear provided along the periphery of the rotating disk is kept in constant engagement with the rack by the spring 16 provided on the slider. Thus, when the rotating disk comes to the concave portion of the rack, it is drawn inwardly by spring 16 so that the two clamps approach one another while they are rotating. The space between them is thereby reduced to allow for the deformation of the bag, thus ensuring perfect reversing of the bag.
After the clamps have made about a 180-degree rotation to complete the reversing operation, they return to their original position, recover the original distance between them, and thus complete one cycle of the bag reversing operation.
In the aforementioned embodiment, the two clamping plates 3 and 4 rotate in directions opposite to each other to hold the bag. As shown in FIG. 9, however, it is also possible to hold the bag from the outside by rotating the eccentric cam 26 provided at the lower part of the shaft 9 which connects with plate 4 and lifting the plate 4 to the same level as the plate 3 after plate 3 has been inserted in the bag to hold it in a tightened state. The clamps holding the bag in this way rotate in the inward direction because of the rack as described above and therefore they turn the bag inside out.
Although motors are used as means for rotating the clamping plates in this embodiment, other suitable means such as hydraulic or pneumatic systems can of course be used instead. The clamping plate 4 may be installed at a position higher than the clamping plate 3 and pushed down to a position level with the plate 3 by hydraulic, pneumatic or other such suitable means.
Further as shown in FIG. 10, the clamping plates 3 and 4 may be provided with auxiliary plates 27 above and below them. When the bag is passed between the clamping plates and the auxiliary plates while the bag is being reversed, the auxiliary plates serve to impart a specified amount of resistance to the passing bag to control the unwanted motion during everting and also to correct any imperfectly everted portion. Thus, the everting operation is made more efficient and perfect. It is further possible to provide the auxiliary plates with heat sources for improving the finish of the everted bag by hot-pressing the clamping plates on both sides with the auxiliary plates 27 after the reversing operation has been completed.
In case the two sheets of cloth or film composing the bag to be reversed are equal in flexibility, the bag is bent along the seam line and reversed uniformly in the reversing and post-treating operations. But if padding is attached to one of the sheets as in the case of a cuff or collar in particular, the bag sometimes is not bent along the seam line because the two sheets are different in flexibility.
In such a case it may be impossible to reverse the bag along the seam line. In order to prevent this inconvenience, the bag is given a crease along the seam line by means of a press or the like for easier bending. This pre-treatment will be described below with regard to a cuff creased by a device of an embodiment shown in FIGS. 11 and 12.
The cuff is placed with its padding up on the press base 29 supported by the support 20. Said press base 29 is provided with the press 28 above it. The press 28 which is made of a hard material such as metal has a suitable interior heating means and is of a shape similar to the seam line of the cuff placed on the press base and either has an acute-angled edge for effective creasing or is provided on its surface with a protrusion having the same shape as the seam line. The press base on which the cuff is placed is made of a heat resisting and elastic material like silicon rubber, and its hardness, thickness, etc. are suitably selected according to the material to be creased. The support for the press base is made of a material hard enough to remain unbent when the pressure is applied.
To describe the process in detail, a plurality of pieces to be creased are arranged on the press base and pressed by lowering a heated press on them. The heating temperature and pressure of the press are suitably selected according to the material of the pieces. For example, polyester bags are pressed preferably at a pressure of about 2 - 5 kg/cm 2 at 150° - 180° C. Since the press is of the same shape or has a protrusion of the same shape as the seam line of each of the pieces and the press base is made of an elastic material, the pressed portion sinks in the press base and the periphery of the remaining unpressed portion rises along the press to leave a crease on the boundary, provided the pressure is applied to the parts uniformly by the press. After the pieces have been creased sufficiently, the press is released and the parts are fed to the reversing apparatus.
If said pre-treatment is given, even bags made up of base cloths of different flexibility can be readily reversed on their seam lines.
The use of the method and apparatus of this invention in the reversing processes of the sewn products manufacturing and other industries can raise the efficientcy of production and make up the shortage of labor as they automate the reversing of bags and baglike articles which have so far been done mostly by hand.