Classifications

• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B9/00—Footwear characterised by the assembling of the individual parts
  • A43B9/02—Footwear stitched or nailed through
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B15/00—Machines for sewing leather goods
  • D05B15/02—Shoe sewing machines
  • D05B15/04—Shoe sewing machines for lock-stitch work
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B21/00—Sewing machines with devices for automatically controlling movement of work-carrier relative to stitch-forming mechanism in order to obtain particular configuration of seam, e.g. programme-controlled for sewing collars, for attaching pockets
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B31/00—Workpiece holders or hold-downs in machines for sewing leather
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B55/00—Needle holders; Needle bars
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B55/00—Needle holders; Needle bars
  • D05B55/08—Driving arrangements for curved needles

Definitions

• the present invention relates to the production of shoe made of leather and the like, and, more precisely, it concerns a method for stitching a shoe upper to a related sole and a machine that carries out this method.
• a disc is fastened to the upper part of this support and rotates with respect to the above mentioned axis, it being driven by gears mounted on the support.
• the disc features an axial hole and another hole, eccentric with respect to the axis, from which a stitching thread goes out.
• the support is introduced into the upper .
• a needle coaxial with the support axis and located outside the shoe upper, cooperates with the support and passes through the shoe upper, thus piercing it, until it enters the axial hole of the disc, so as to hitch the thread guided by the eccentric hole.
• the needle pulls a thread slipknot, which is then latched by a looper or crochet external to the upper.
• the holes made by the needle in the upper must be large enough to allow passage of a double thread.
• Another object of the present invention is to propose a machine which carries out this method by a simple, safe, practical and reliable technical solution which can be widely used and complies with safety requirements.
• the above mentioned method is performed by means of a shoe sewing machine that it includes: a stitching member which is introduced into the shoe upper associated to the sole of the shoe being stitched, with a needle guided slidmgly at the end of said stitching member; a crochet, situated outside the shoe and cooperating with said needle to make a stitching; driving means for moving the upper together with the sole joined thereto; a first frame of said driving means, that rotates about a vertical axis substantially coincident with the axis of the needle while stitching; a second frame of said driving means, carried by said first frame and operated to move along a horizontal direction crosswise to said vertical axis; a cradle of said driving means, for supporting said shoe upper and said sole, said cradle being carried by said second frame and moved along a path orthogonal to said advancement direction of said second frame, with a variable attitude.
• a stitching member which is introduced into the shoe upper associated to the sole of the shoe being stitched, with a needle guided slidm
• Figure 1 shows a front view of the machine for stitching a shoe upper to a related sole according to the subject method
• - Figure 2 shows a corresponding lateral view of this machine, in cross-section taken along the line II-II of Figure 1;
• Figure 3 shows a corresponding plan view of this machine, in cross-section taken along the line III-III of Figure 1;
• Figure 4 shows a fragmentary lateral view of this machine, with a partial cross-section taken along a vertical plane, so as to point out internal parts of the machine;
• Figure 5 shows a longitudinal section view of a stitching member of the subject machine;
• Figure 6 shows a perspective view of a looper or crochet of the subject machine
• FIG. 7 shows a perspective view of the crochet during a stitching step, seen at a different angle
• - Figures 8c and 8d show the same view of the particular T, in different embodiments;
• - Figure 9 shows a partial front view of the machine, in an initial step of the stitching cycle;
• - Figure 9a shows a corresponding plan view of the shoe being stitched in this last mentioned step
• - Figure 10 shows the same front view of the machine, during a subsequent stitching step
• FIG. 10a shows a corresponding plan view of the shoe being stitched in th s last mentioned step
• FIG. 13 shows the same front view of the machine, m another stitching cycle step;
• FIGS 13a and 13c show corresponding plan views of the shoe being stitched in this last mentioned step;
• FIG. 13b shows an enlarged view of particular K2 of Figure 13.
• reference numeral 1 indicates a machine for stitching a shoe upper to a related sole for manufacturing e.g. a moccasin type shoe.
• the machine 1 includes a stitching member 10, situated over a bed 2.
• the stitching member 10 is to be introduced into a shoe upper 3 associated to a related sole 4 forming the shoe to be stitched.
• this shoe will be indicated with numeral 5 in the following description.
• the stitching member 10 includes a shaped arm 11 extending substantially on a vertical plane and having a two curved points, so as to define two consecutive terminal and intermediate sections 11a, lib curved in opposite directions.
• the terminal section 11a is curved downwards ( Figure 5) .
• the shape of the arm 11 facilitates its introduction into the upper 3 to be stitched to the related sole 4, so as to bring the terminal section 11a up to the toe of the shoe 5.
• a channel 12, extending along the shaped arm 11, houses in its terminal part a needle 13, whose curving corresponds to the curving of the above mentioned terminal section 11a of the arm 11.
• the needle 13 moves the stitching thread 6 and cooperates, during the stitching step, with a looper or crochet 7, situated under the sole 4 to be stitched, outside the shoe; the crochet 7 can be rotary or oscillating, in accordance to well known techniques.
• the upper part of the crochet 7 features a plate 77, which presses the leather , during the stitching and is operated, by a suitable cam (not shown) , to move vertically in time relation with the crochet 7 movements.
• the plate 77 In its central part, the plate 77 has a hole 77a, through which the needle 13 passes.
• the plate 77 is brought to a raised position, so as to press the material when the stitches are made, while when the needle 13 returns inside the arm 11, the plate is lowered to a release position, which the material is released and allowed to advance.
• the crochet 7 has an element 17, so called thread preserver, which keeps the thread unwinding from the bobbin at a suitable distance, thus preventing it from being caught by the crochet latch or by the needle tip.
• the needle 13 is reciprocated by a flexible member 14, which is introduced into the channel 12 of the arm 11.
• the flexible member 14 is moved by a piston 15 controlled by a suitable mechanism 16 formed by a connecting rod and a crank.
• the flexible member 14 is formed by a roller chain 14a. Nevertheless, the flexible member 14 can be otherwise formed by a series of balls with diametrical holes through which a metallic wire 14c passes, so as to pull the needle 13 (see Figure 8c) .
• Figure 8d shows another embodiment of the flexible member 14, which includes a band 14d of plastic material, like e.g. teflon, whose opposite surfaces feature each one a series of transversal notches 14e, regularly spaced apart . These notches 14e allow the band 14d to bend, since they get larger to compensate the extension of the dilatation of the side becoming longer and get narrower along the side which is compressed.
• the terminal section 11a of the arm 11 has a holed part lie, that features a hole for precisely guiding the needle 13.
• This holed part lie can be formed by a removable bushing, so as to be easily substituted for e.g. changing the diameter of the needle to be used.
• the shaped arm 11 of the stitching member 10 is fastened to a head 60, which cantilevers from a column 61.
• the column 61 is slidably guided in a tube 62 fastened to the bed 2.
• the head 60 is moved between a lowered operative position and a raised inoperative position, indicated with broken line 60a in Figure 4.
• a shoe to be stitched is introduced and removed after stitching.
• the head 60 is driven in this motion between the two positions by a motor 63 carried by the column 61.
• the motor 63 drives, via transmission means 64, a screw 65 which is supported inside the column 61 with possibility of rotation about a vertical axis.
• the screw 65 is coupled with a corresponding nut screw 66 fastened to the tube 62 and crossing a slot made in the column 61.
• the column 61 is guided by a pair of vertical guides, situated on both sides thereof, which engage corresponding idle rollers 69 carried by the tube 62 ( Figure 3) .
• a driving shaft for operation of the mechanism 16 which activates a plunger 15.
• the driving shaft 70 is operated with continuous motion by a motor 71, that is carried by the column 61, via transmission means 72 ( Figure 2).
• the driving shaft 70 transmits this continuous motion by means of a pair of bevel gears 73, to a vertical shaft 74.
• the vertical shaft 74 has a splined portion 74a, which is coupled with a tubular shaft 74b.
• This tubular shaft 74b transmits the motion, via other transmission means 75, to another pair of bevel gears 76, one of which is keyed onto a driven shaft 78, which is carried rotatably inside the bed 2.
• This driven shaft 78 operates, by a transmission member 79, the crochet 7 and the cam for movement of the plate 77.
• the head 60 In its front part, the head 60 carries also a device 18, so called thread puller and widely known in the art, which holds the thread 6 and is operated by the driving shaft 70.
• the thread 6 is guided externally with respect to the arm 11 of the stitching member 10 and is introduced in the terminal section 11a of the arm 11 in the region of an aperture 19 ( Figure 7).
• the shoe upper 3 and sole 4 to be stitched thereto, are carried, associated to one another, by driving means 20 located on the bed 2, under the stitching member 10.
• These driving means 20 include a first frame 30, a second frame 40 and a shoe supporting cradle 50.
• the first frame 30 rotates about a vertical axis, substantially coinciding with the axis of the needle 13, during stitching of the shoe.
• the second frame 40 is carried by the first frame 30 and is operated to move in horizontal direction crosswise to the last mentioned vertical axis.
• the shoe supporting cradle 50 is carried by the second frame 40 and moves along a variable path, basically along a direction longitudinal to the shoe 5 to be stitched and orthogonal to the second frame 40 movement direction.
• the first frame 30, substantially quadrilateral is equipped, in its central part, with an internally toothed crown 31, carried rotatably by means of a roll-bearing fifth wheel 8 fastened to the bed 2.
• Roll-bearings 9 are interposed between the fifth wheel and the bed 2.
• the crown 31 is in a gear meshing with a vertical pinion 32, operated by a motor which is not shown.
• the second frame 40 includes a pair of parallel side panels 41, joined by cross bars 42. In their lower parts, the side panels 41 are equipped with respective pairs of nut screws 43.
• the first frame 30 supports rotatably a pair of parallel horizontal screws 33, which engage the nut screws 43 of the second frame 40.
• the screws 33 are operated, in counter-rotating directions, by a motor 34 carried by the frame 30, via a driving belt 35 mounted on pulleys 36 which are keyed onto these screws 33.
• the side panels 41 On their sides facing the inside of the frame 40, the side panels 41 have respective grooved guides 44.
• the grooved guides 44 define a part of the path of related transmission means 45, basically constituted by a chain trained around toothed wheels 46 mounted inside the side panels 41 and operated in alternate rotation by a related motor 47.
• the grooved guides 44 include an arc-like section 44a, which is located in intermediate position and is engaged by the fore rollers 51a of the cradle 50.
• the intermediate arc-like section determines inclination of the cradle 50 with respect to the second frame 40 of the driving means 20.
• the grooved guides feature also, in their rear part, a sloping section 44b, along which the rear rollers 51b of the cradle 50 run. Otherwise, the cradle 50 can be inclined by a pair of step motors, fastened to relative screws carried by a horizontal slide.
• a support means 55 for supporting the shoe being stitched is fastened to the cradle 50.
• This support means 55 is substantially formed by a jig made from a slotted sheet material, thus featuring an opening which is shaped in accordance to the profile and dimensions of the shoe 5 to be stitched. Therefore, the ig is replaced with another when the shape or dimension of the shoe 5 are changed.
• the slotted opening features a flange 55a, that supports the edge of the sole 4 of the shoe 5 (see Figure 10b) .
• the height of the flange 55a varies to compensate diverse thickness of the sole and diverse length of the path through the upper and sole where the needle enters.
• the flange 55a is interrupted in the region of the heel 4a of the sole 4 ( Figure 13b) .
• the edge of the sole 4 is advantageously kept firmly by locking means, which stabilize the position of the shoe, with the sole resting on the flange 55a.
• These locking means are formed by e.g. two or more square elements 155.
• One wing of each square element is pivoted to the support means 55, with possibility to rotate with respect to the wing axis, so that the other w g holds down the sole edge.
• the head 60 is lowered again, so as to introduce the arm 11 of the stitching member 1 into the upper 3 of the shoe 5, as indicated with broken line la in Figure 9.
• the shoe 5 is arranged in such a way as to align the holed portion lie of the terminal section 11a of the arm 11, that supports the needle 13, with a stitching start point, also called zero point, indicated with A in Figure 9a.
• This point A is preferably situated in the region of the median area and at the internal side of the shoe profile.
• Needle 13 operation together with the coordinated operation of the crochet 7 and movement of the shoe 5 carried by the driving means 20, determine the stitching of the upper 3 to sole 4, by e.g. double thread knotted stitch .
• the flexible member 14 operates the needle 13 with alternate movements, so as to make it go in and out of the terminal section 11a of the arm 11.
• the stitching advancement is determined by the backward movement of the cradle 50 with respect to the second frame 40 of the driving means 20, in combination with a translation of the second frame 40 with respect to the first frame 30.
• the first frame 30 of the driving means 20 performs a limited rotation to allow a better penetration of the terminal section 11a of the arm 11 in the region of the upper tip.
• the position of the cradle 50, supporting the shoe 5 changes because its lower part slopes downward due to the movement of the fore rollers 51a of the cradle 50 in the arc-like median section 44a of the grooved guides 44. This downward sloping allows the terminal section 11a of the arm 11 to reach the shoe tip, as seen in Figure 10.
• the upper surface of the plate 77 is rounded, so as to fit any cradle 50 inclination. Then, the cradle 50 is moved in the opposite direction and this, together with a suitable translation of the second frame 40, determine stitching of the shoe outer edge, up to a point D, substantially symmetrical to the zero point A ( Figure 11) .
• the first frame 30 of the driving means 20 is to rotated a bit less than half a turn ( Figure 12) .
• the frame 30, driven by the pinion 32 acting on the toothed crown 31 rotates about a vertical axis coinciding with the piercing axis of the needle 13.
• the shoe 5 carried by the driving means 20 takes a reversed position with respect to the arm 11, which now faces the rear part of the upper 3 ( Figure 13) .
• the cradle 50 attitude is changed, so as to bring the stitching line still nearer to the heel outer profile in the region where the needle goes out.
• the method and machine according to the present invention fulfill the objects of the present invention to automatically sew a shoe upper to a related sole, thus guaranteeing a constant working quality and high production throughput.
• the working quality no longer depends on the operator' s ability, since the stitching is performed by automatic motion of the shoe being stitched with respect to the stitching member, along a predetermined path. This allows also to comply with very strict safety requirements .
• the particular shape of the stitching member introduced inside the upper and the change of the shoe attitude during the stitching allow to perform the stitching from inside toward outside also in the region of the shoe tip.
• the machine operation is controlled by electronic means, which command different working steps m the best way.
• These data can be acquired by e.g. learning technique; in this case the operator manually imposes the machine movements, so as to optimize the stitching line. These movements are detected and corresponding date are stored to be used subsequently for stitching shoes of the same model and size.
• control means can be equipped with sensor means (e.g. video cameras) which scan the profile of each single shoe, so as to control the electronic means in relation to the detected data.
• sensor means e.g. video cameras
• the machine is stopped, so as to substitute the thread bobbin before starting.
• Another advantage of the present invention derives from the fact that it guarantees a perfect water-tight stitching .

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=11343152

Family Applications (1)

Country Status (5)

Families Citing this family (8)

Family Cites Families (6)

• 1998
  • 1998-05-05 IT IT98BO000280A patent/IT1300004B1/it active IP Right Grant
  • 1998-08-01 TW TW089202215U patent/TW454452U/zh unknown
• 1999
  • 1999-05-05 EP EP99915974A patent/EP1002150A2/en not_active Withdrawn
  • 1999-05-05 AU AU34383/99A patent/AU3438399A/en not_active Abandoned
  • 1999-05-05 WO PCT/IB1999/000806 patent/WO1999056573A2/en not_active Application Discontinuation

Non-Patent Citations (1)

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