MXPA00009891A - Machine for stitching a shoe upper to a relative sole - Google Patents

Abstract

A shoe sewing machine includes a longitudinal guide (7), which has a bottom surface for receiving in abutment edges (9a, 8a) of an upper (9) and a relative sole (8). The guide steers the edges toward a curved needle (6), that oscillates crosswise to the guide (7), while an idle wheel (17), situated under the longitudinal guide (7), supports the edge (8a) of the sole (8) during stitching. The wheel (17) is carried by the top of a swinging arm (13) which can assume any orientation, so as not to hinder the shoe movement during stitching. The arm (13) is kept in a raised working position (L) and can be lowered, so as to move away the wheel (17) when the upper (9) is set in or removed.

Description

MACHINE FOR SEWING THE TOP OF A SHOE TO A RELATIVE SOLE Field of the Invention The present invention relates to the process of sewing upper parts to respective lower elements, such as soles, to obtain shoes.

Antecedents of the Invention.

There are machines for sewing the upper parts of a shoe and the soles, by means of a machine for sewing edges of leather goods, adapted with suitable tools.

An example of this machine is the one described in the Patent No. 4,848,252 of the same Applicant.

This machine includes a longitudinal guide defining two uniform inclined planes, mutually converging upwards and defining respective working surfaces, on which the pieces of skin will be moved for the sewing process.

The shaft is operated to oscillate around its longitudinal axis, so that it moves the needle between a raised and lowered position, in which it passes through the edges of the skin pieces.

The needle cooperates with a rotating hook, commonly known as "crochet", to which it is attached to a thread sewing bobbin.

This machine makes it possible to sew the ends of two leather articles, for example the upper part of a shoe and the leather cover. However, the machine can not sew the sole to the top, if it is of the open type, for example it forms a strip that will be attached to the sole along an edge. As indicated above, this operative limitation has been overcome, supplying the machine with suitable tools derived from the machine of the aforementioned North American Patent. The international publication No. WO97 / 05316 also owned by the Applicant, describes a method and a machine related to sewing a sole to an upper part of an open type shoe. Basically, this machine is formed by a head, which supports the means of operation of the needle and hook, and a pivoting arm. A longitudinal guide that supports the articles for the sewing process is located at the end of this pivoting arm. The head is suitably inclined with respect to a vertical plane, so that a portion of the trajectory is circular covered by the needle in the region of the sewing area, and has a direction to make it easier for the needle to enter the top and leave the sole.

The pivoting arm is equipped with a motorized means, pedal operated, which allows to place this arm in appropriate positions during the sewing process of the shoe, so as not to obstruct the movements of the shoe. In addition, the pivoting arm includes an apparatus for maintaining space-free to independently guide the positions assumed by the arm. The Applicant has devised another machine, described in the European Patent Application No. EP 96941797.1, which overcomes the disadvantages of the machine described above. This last machine keeps the head inclined, according to the technique already used in the previous machine, so that the arm is eliminated, which is replaced with a stationary guide secured to the head which extends downwards. The lower end of the guide has a base that supports the inner edge of the sole during the sewing process. This last machine is more compact, simple and therefore cheaper to produce with respect to the first, therefore it is more commercially appreciated, even though its operational limitation results from its structure. In fact, the shoe sewing process can not be completed by completing the closed circuit at the starting point. This would prevent the base, which, during the sewing process is located inside the shoe, from leaving it, remaining trapped therein and making it impossible to remove the shoe from the guide. To avoid this inconvenience, the sewing process is interrupted before the last sewing, so that the shoe can be removed and subsequently, the sewing process will be finished manually by the operator. It should be noted that the operational limitation described above must be considered from both technical and commercial points of view and within a context in which the only alternative was manual labor or much more complex and laborious processes and apparatus. Therefore, however, this limitation has not been to the detriment of commercial success.

Summary of the Invention. The object of the present invention is to propose a machine which allows, completely and definitively, to sew the upper part of a shoe open to a relative sole, without the subsequent final operations and / or without interrupting the sewing process before said shoe is actually finished. Another object of the present invention is to propose a machine, whose shaping, with small adaptations, allows to perform a particular sewing process, similar to one in which the edge of the upper part of a shoe overlaps the part of a corresponding sole.

The objects mentioned above are achieved, according to the contents of the Claims by means of a machine for sewing the upper part of a shoe to a related sole, wherein the machine includes: a longitudinal guide formed in the lower free end of a bracket placed substantially vertically, said guide forming an upper stop for the respective edges of the upper part of a shoe and a related sole, which advance along said guide; a curved needle having a shape similar to an arc, said needle being moved to oscillate in a plane transverse to the guide between a starting position, next to said guide and a position of maximum rotation, in which the needle passes first to through said edge of the upper part and subsequently through the edge of the sole while the needle is also moved alternately parallel to said guide according to the blows of a predetermined stitch; a rotating hook, with a spool of sewing thread, associated thereto, said rotary hook being located adjacent to the guide on the side opposite to the side where the needle enters said upper part of the shoe, said rotary hook cooperating with the needle, so that sewing is performed; a pivoting pivot arm near a relative support and adjacent said guide; a rotating wheel transported by a free end of said pivoting arm and located below said guide, said wheel having such positioning that it rotates about a horizontal axis transverse to the guide, and coincides with the axis of the pivot of said arm , so that the wheel forms a lower stop and supports the inner surface of the sole edge.

Brief Description of the Drawings. The features of the present invention have been pointed out below, with a particular reference to the accompanying drawings in which: Figure 1 is a perspective view of the front of the machine, where the means of sewing; Figure 2 is the same perspective view of Figure 1, and shows the position of a member of the machine in which the upper part of the shoe can be placed or removed; Figures 3a, 3b are perspective views of a detail of the sewing area, seen from different angles; Figure 4 is a front view of the sewing area with the machine prepared for a first type of seam; Figure 5 is a perspective view of a shoe sewn by the machine of the present invention, through the means illustrated in Figure 4; Figure 6 is the same front view of Figure 4, of the machine prepared for a second type of seam; Figure 7 is a perspective view of a part of a shoe stitched by means of the machine of the present invention, through the means illustrated in Figure 6. Detailed Description of the Invention. With reference to the aforementioned Figures, the number 1 indicates a head of a sewing machine, which supports operating means for operating the sewing means thereof. The head 1 is transported, in a known manner, by means of a base block which has such a shape that the head is inclined appropriately with respect to the vertical. The head 1 supports in a known manner, a longitudinal axis 4 equipped with a radial arm 5. A curved needle 6 having an arc shape, is concentric with respect to the axis 4. The curved needle 6 is secured to the free end of the radial arm 5 (see also US-A-4, 848, 252). The head 1 is inclined so that the part of the circular path covered by the needle 6 which is in the Region of the sewing area has a suitable direction to make it easy for the needle to enter and exit at desired levels. The needle 6 moves cyclically from a starting position, next to a longitudinal guide 7, and an active position of maximum rotation, in which the needle pierces during the sewing process, first the edge 9a of an upper part 9. and subsequently the corresponding edge 8a of a sole 8, coupled by the guide 7.

In particular, the upper part 9 is of open type and will be attached to the related sole 8, suitably formed, in the region of its lower edge 9a. The axis 4 of the needle 6 also moves alternately in axial form, according to the previously set amplitude strokes, in a suitable time relationship, with the oscillation of the needle 6, as will be explained later. The needle 6 operates in conjunction with a rotating hook 10, commonly known as "crochet", to which it is attached to a bobbin of sewing thread. The crochet 10 is placed next to the longitudinal guide 7, on the side opposite the side where the needle 6 enters the upper part of the shoe, and moves, in turn, in synchrony with the axis 4 of the needle 6. As shown in the aforementioned document WO-A-9705316, a leg 20 indicated with the dotted line in Figures 4 and 6, is placed on the same side of the crochet 10. The leg 20 moves transversely to the guide 7. , in a suitable time relation with the oscillation of the needle 6, so that it holds the sole 8 during the piercing of the needle. The needle 6 passes through a slot 21, made in the leg 20. A skin pressing element 52, placed on the side where the needle enters the upper part of the shoe, moves transversely to the guide 7 , in a suitable time relation with the oscillation of the needle 6, so that it remains below the top 9 after each stitch, when the needle 6 is extracted.

A wrinkling group 53 is placed on the side where the needle 7 enters the upper part of the shoe, and is operated on the appropriate command, so that it moves alternately, longitudinally to the guide 7 and transverse to it, in a suitable relation of time with the oscillation of the needle 6.

The wrinkling group 53 carries a head 54 which acts on the upper part 9, to increase its advancing steps with respect to the sole 8, thereby wrinkling the edge 9a of the upper part, for example, during the sewing of the foot of the shoe.

The longitudinal guide 7 is formed in the lower free end of a bracket 12, placed in a substantially vertical form and secured to the head of the machine 1, the bracket 12, and also the guide 7 has the task of guiding the edges 9a, 8a of the upper part 9 and of the sole 8, during the sewing process.

According to a first embodiment shown in detail in Figure 4 the guide 7 defines two planes of operation 7a 7b, in a substantially vertical form and oriented in opposite directions. The guide has a rest, prepared in a known manner and therefore not shown, which is open to the head 1, to allow the needle to pass through it.

The respective teeth 14, 15, independently adjustable in height, operate in conjunction with the aforementioned operation planes 7a, 7b.

In this way, the guide 7 forms an upper stop for the edges 9a, 8a of the upper part 9 and the sole 8, which allows to adjust its mutual position for the sewing process and to direct these edges 9a, 8a correctly to the point where the needle passes 6.

The guide 7 described above allows to obtain a shoe similar to the one illustrated in Figure 5.

According to a second embodiment, shown in detail in Figure 6, the guide 7 defines a rounded channel 70 with the concave portion turned low.

The profile of the channel 70 allows to define a type of shape, because it is possible to sew the upper part 9 to the sole 8 in such a way that the end 9a of the upper part 9, overlaps the edge 8a of the sole 8, wrapping it partially.

In this way, the needle 6 pierces the end 9a of the upper part twice, at the points where it enters and leaves.

In Figure 7, the aesthetic effect of the sewing process described above can be observed, which shows a part of the shoe obtained according to this shape.

This second way of sewing is particularly efficient to obtain a shoe with high resistance to water.

The longitudinal guide 7, in both described modes, operates in conjunction with a wheel 17 placed below and rotating about a horizontal axis transversely to the guide 7. The transported rotating wheel 17 is on the upper part of an arm 13, the which swings freely with respect to a relative support 130 secured to the head 1. The pivot axis of the arm 13 coincides with the axis of rotation of the wheel 17, so that the oscillation of the arm 13 does not change the position of the wheel. The support 130 has means 1 31 for keeping the arm 13 in a high operating position L (see Figures 1, 4 and 6). In this situation, the wheel 1 7 is at a predetermined distance from the longitudinal guide 7, and acts as a stop and support for the inner surface of the edge 8a of the sole 8. The means 131 are controlled to lower the arm 13 to adjust a shoe and remove the position K in which the wheel 17 is far from the guide 7 (Figure 2). In this position, it is possible to adjust an upper part 9 that will be sewn, as well as, when the sewing process is completed, remove an already sewn upper part to the relative sole. The means 131 are formed, for example, by a vertical axis 132, in which the arm 13 is articulated, so that it is moved vertically and subjected to the action of elastic means, not shown, which maintains the operating position L before mentioned.

The operating means 133, for example driven by tires, can be operated by a button 1 34 to act on the shaft 132, so that the arm 13 is lowered to the adjustment of the shoe and to the removal position K, in contrast to the elastic means mentioned above; when the button 134 is released, the operating means 133 returns the arm 13 to the high operating position L. The first operation of the sewing cycle, according to both forms, is mounted to the upper part 9, lowering and raising the arm 13, as mentioned above. Therefore, the edges 9a, 8a of the upper part 9 and of the sole 8 are placed along the guide 7, and subsequently, are moved manually to coincide with one another during the advance. While this is done, they are sewn, with the sole 8 supported by the wheel 17, which is wound on the inner surface of its edge 8a. The means of the machine drive the needle in an oscillatory movement, in a known manner, so that it first passes through the edge 9a of the upper part and subsequently through the end 8a of the sole 8, until the needle reaches its maximum rotational position (Figures 4, 6). In said position, the tip of the curved needle is inserted into the crochet 10, where the seams are tied in a reciprocal manner. At the same time, the needle 6 and the crochet 10 move in synchronized manner along the respective axes, by means of a predetermined sewing stitch, thus realizing the advance of the upper part 9 and the sole 8. Subsequently, remove the needle 6 from the sewing material, and return it to its starting position. The curved needle together with the crochet 10, move back by means of the same stitch, while the blow already completed in the forward direction lasts. The leg 20 and the skin pressing element 52 work in the manner explained above, during each stitch, which is performed in accordance with the cycle described above. During the sewing process, the operator intervenes to activate the wrinkling group 53, which, by grouping the upper part 9, which is compensated for by its larger peripheral extension with respect to the sole 8 in the foot area, curving from this the sole. During the sewing process, the operator suitably moves the arm 13, so that its position does not hinder the movements of the upper part of the shoe 9. The sewing process is completed along the entire length of the shoe, and the last stitches passing over the initial stitches, so that the seam path C becomes a closed circuit, and at the same time it is properly fixed (Figures 5, 7). Subsequently, the arm 13 is lowered by pressing the button 134, and the shoe already obtained is removed.

The operation is completed by cutting the stitches, without additional operations.

Therefore, it seems that the objects mentioned in the introductory statements, are obtained completely by a simple, reliable and extremely compact technical solution.

It should be noted especially that due to the fact that a complete and definitive sewing process is obtained, it increases productivity and it is possible to avoid the use of specialized operators to manually complete the sewing process. This compensates for the additional cost, however low, that results from the addition of the arm 13 and the means attached thereto.

It is understood that what was described above is only a non-limiting example, therefore the possible constructive variants remain within the protective scope of the present technical solution, as described above, and in the accompanying Claims.

Claims (3)

R E I V I N D I C A C I O N E S Having described the present invention, it is considered as a novelty and, therefore, what is claimed as property is contained in the following REVINDICATION ES

1 . A machine for sewing the upper part of a shoe to a related sole, further characterized in that the machine includes: a longitudinal guide (7) formed in the lower free end of a bracket (12) positioned substantially vertically, forming said guide ( 7) an upper stop for the respective edges (9a, 8a) of the upper part of a shoe (9) and a related sole (8), which advance along said guide (7); a curved needle (6) having a shape similar to an arc, said needle being moved to oscillate in a plane transverse to the guide (7) between a starting position, next to said guide (7) and a position of maximum rotation , in which the needle (6) passes first through said edge (9a) of the upper part (9) and subsequently through the edge (8a) of the sole (8) while the needle (6) is also moved in alternative form parallel to said guide (7) according to the blows of a predetermined stitch; a rotating hook (10), with a spool of sewing thread associated thereto, said rotating hook being located next to the guide (7) on the side opposite to the side where the needle (6) enters said upper part of the shoe, said rotary hook (10) cooperating with the needle (6), so that the sewing is performed; a pivot arm (13), rotatable near a relative support (130) and next to said guide (7); a rotating wheel transported (17) by a free end of said pivoting arm (13) and located below said guide (7), said wheel having such positioning that it rotates about a horizontal axis transverse to the guide ( 7), and coincident with the axis of the pivot of said arm (13), so that the wheel (17) forms a lower stop and supports the internal surface of the sole edge (8).

2. A machine as described in Claim 1, further characterized in that said support (1 30) includes means (131) that keeps said arm (13) in a high operating position (L), in which said wheel (17) is at a predetermined distance from said guide (7), said means (131) being operated to lower said arm (13) to place a shoe and a removal position (K), in which the wheel (1 7) moves away of said guide (7), so that the upper part (9) that will be sewn is placed and said upper part is removed once sewn to the relative sole (8).

3. A machine as described in claim 1, further characterized in that the longitudinal guide (7) defines two planes of operation (7a, 7b), substantially vertical and oriented in opposite directions, where they are coupled by the respective edges of said upper part (9) and sole (8). A machine as described in Claim 3, further characterized in that said longitudinal guide (7) includes a pair of teeth (14, 15), located near said operation planes (7a, 7b) respectively, and defining, together with these planes, the position of said edges (9a, 8a) of the upper part (9) and sole (8). A machine as described in Claim 4, further characterized in that said teeth (14, 15) are adjusted independently in height, to adjust with the mutual position of said upper part (4) and sole (8). A machine as described in Claim 1, further characterized in that said longitudinal guide (7) defines a round channel (70) with the concave portion turned downward, to maintain a shape and a position of said edge (9a) of said upper part of the shoe (9), so that it overlaps said edge (8a) of the sole (8), twice drilling the needle (6) said edge (9a) of the upper part of the shoe (9), at the points where it enters and leaves. A machine as described in Claim 1, further characterized in that a wrinkling group 53 is positioned adjacent said longitudinal guide (7), and is equipped with a head (54) that moves alternately in two directions in the form transverse to said guide (7), so as to fit the edge (9a) of said upper part (9), and longitudinally to this guide (7), to make wrinkles in said edge (9a) of the upper part of the shoe (9). A machine as described in Claim 1, further characterized in that the leg (20) is located on the same side of the guide (7) as the crochet (10), and transversely moves said guide (7), of so that during the piercing of the needle (6) the sole (8) is stopped, said leg (20) having a hole (21) through which said needle (6) passes freely. A machine as described in Claim 1, further characterized in that a skin pressing member is located adjacent said guide (7), and moves transversely therein to stop said upper part (9) after which each stitch is made, during the extraction of the needle (6).