US3348249A

US3348249A - Multiple shoe lasting

Info

Publication number: US3348249A
Application number: US483544A
Authority: US
Inventors: Markevitch Igor Ivan
Original assignee: Arnav Ind Inc
Current assignee: Arnav Ind Inc
Priority date: 1965-08-30
Filing date: 1965-08-30
Publication date: 1967-10-24
Anticipated expiration: 1984-10-24

Description

24, 1967 l. MARKEVITCH 3,348,249

MULTIPLE SHOE LASTING Filed Aug. 30, 1965 2 Sheets-Sheet 1 INVENTOR Igor I. Morkevifch ATTORNEYS 1967 l. MARKEVITCH MULTIPLE SHOE LASTING 2 Sheets-Sheet 2 Filed Aug. 30, 1965 ATTORNEYS United States Patent Ofitice 3,348,249 Patented Oct. 24, 1967 3,348,249 MULTIPLE SHOE LASTING Igor Ivan Markevitch, Wayne, N..I., assignor to Arnav Industries, Inc., Kenilworth, N.J., a corporation of Delaware Filed Aug. 30, 1965, Ser. No. 483,544 7 Claims. (Cl. 12-1) ABSTRACT OF THE DISCLOSURE Apparatus for lasting a plurality of shoes comprising means to place and remove the shoes to be lasted into a plurality of shoe upper premolded elastomer lasting bags, that are surrounded by a fluid-tight chamber and means to apply and release hydraulic pressure in said fluid-tight chamber and on said lasting bags, said pressure being used to place pressure on the lasting bags to last the shoes.

This invention relates to an improved process and apparatus for lasting shoe insoles to shoe uppers, and more particularly relates to a much more economical, automatic, multiple bag lasting process and apparatus.

With the ever increasing stress of competitive automation and the demand for increased production in the shoe industry, a trend in the simplification of shoe construction has resolved itself into a process referred to as the Compo method. This term refers to the technique of joining by adhesive methods a sole of any suitable material to a pro-formed upper. To accomplish the complete lasting operation, the prior art uses a number of lasting machines. These are, in the order of operation, toelasters, sidelasters, and heelseat lasters and the principal function of all three machines is to pull and overlap the various extended portions of the shoe upper and to press them into a precemented shoe bottom. The prior art toelasting, sidelasting and heel-seat lasting machines are very expensive, relatively diflicult to use and their output of shoes lasted per hour is relatively low.

Therefore, an important object of this invention i to provide a relatively inexpensive lasting machine which will perform the functions of the three presently used toe, heel and sidelasting machines.

Another important object of this invention is to provide a lasting machine that is semi-automatic and rela tively easy to use.

Another important object of this invention is to provide a shoe lasting machine that has a faster operating cycle and a much higher output per cycle than that of prior art lasting machines.

Another important object of this invention is to provide a bag lasting machine having elastomeric bags capable of pressing against the entire periphery of the shoe, drawing the upper tight to the last, and uniformly joining the upper to the insole.

Another important object of this invention is to provide a bag lasting machine that will automaticaliy posi tion, last and eject a plurality of shoes per cycle.

Further objects and advantages within the scope of this invention relates to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinations of parts, elements per se, and to economics of manufacture and numerous other features which will be apparent from a consideration of the specification and drawing of a form of the invention in which:

FIGURE 1 is a perspective View of one preferred embodiment of the bag lasting machine of this invention;

FIGURE 2 is a sectional view which shows an illustrative lid moving mechanism;

FIGURE 3 is an enlarged sectional view of the pin guide Way;

FIGURE 4 is a bottom view of a shoe upper and insole before bag lasting;

FIGURE 5 is a bottom view of a shoe upper and insole after bag lasting; and

FIGURE 6 is a shoe formed molded bag for-med on a lasting pattern.

In general, the shoes are prepared for lasting in the following manner. Prior to lasting a completely sewn upper is coated along the extended lining of its periphery with a heat reactive, pressure sensitive adhesive, such as neoprene. This extended lining will later be Wrapped over the last. Similarly, the periphery of an exposed insole is coated on its exposed side with the same adhesive and both components are permitted to dry until the solvents are completely evaporated. Then the upper and the insole are assembled on the last by manually orienting the two components and tacking or stapling the back of the shoe at a predetermined location. Alternately, using some of the newer adhesives the need of precementing both components is not necessary and assembly is performed by merely cementing the exposed insole and uniting it with the up er.

The preassembled shoe is now ready to be placed in the lasting machine. conventionally, in the prior art, from this point on, three lasting machines are used; that is, the toe laster, the side laster (Camborium), and the heel-seat laster. These prior art machines are expensive, averaging over $22,000 per machine and have a maximum output of only forty 36-pair cases per day per machine. When using the apparatus of this invention one merely places a plurality of lasts with preassembled shoes on a plurality of lasting pins and performs the three above lasting operations simultaneously and more expeditiously. Furthermore, the machine disclosed herein is cheaper than the combined prior art lasting apparatus and its lasting operation is virtually automatic. Since use of all of the above-mentioned prior art machines requires dexterity and skill on the part of their operators, the herein disclosed apparatus which merely requires the placement of a plurality of prelasted uppers on a plurality of pins is a big advance in the art. Placing the pre-lasted shoes on the pins represents all the effort the operator must exercise. Pressing the starter button control activates a hydraulic cylinder which retracts the pins which carry the pro-assembled shoes into the pockets of the corresponding suspended bag elements. An automatic series of valves close the sliding lid door, close the locking clamps, and control the entry of hydraulic fluid into the chamber. The hydraulic fluid presses against the molded elastomeric bags. The bags in turn are specifically shaped to press and last the peripheries of the shoes by drawing the upper tight to the last, and subsequently uniformly press the extended portion or lasting allowance of exposed upper to produce a positive joint between the upper and the insole. When the pressure lasting step is completed, pressure sensitive valves automatically release the air pressure and the cycle automatically reverses to open the sliding door, raise the pins and eject the now lasted shoes. The complete cycle is then repeated. The entire lasting sequence takes approximately ten seconds or 6 cycles/min. Thus, one lasting unit of this invention havingonly two pins would produce eighty 36-pair cases per day as contrasted with the 40 cases produced by the prior art lasting process.

FIGURES 1 and 2 show one embodiment of this invention which has a sliding steel holddown lid 1 which is opened and closed by a double acting air cylinder 2; cylinder 2 controls piston 3 attached to a clevis mount 4 which is mounted on the top edge of lid 1. Due to the high pressures required, supplementary lid closure retaining means are desirable; those shown in the drawings have two hydraulic clamping cylinders 5, each clamping cylinder controls a piston 6 which is attached to and controls the movement of connecting bar 7. Each clamping cylinder is retained in place by a pivot mount 8 mounted on table 21. Connecting bars 7 each in turn control the movement of two quick clamps 9 which are pivotally mounted to the rim ledges 14 in a manner that facilitates alternatively clamping and releasing lid 1. The movement of a pair of lasting pins 10 is controlled by pin cylinder 16. Each pin simultaneously moves up and down in specially molded elastomeric bags 11 through a fluid tight pin guide way 22. The down position of pin 10 positions the shoe for lasting at the bottom of bag 11 and the up position ejects last 26 and shoe 27 or positions them for manual removal from bag 11. The rigid hollow housing 12 shown is a metal case which contains two fluidly sealed elastomeric bags 11. The housing 12 is arranged about bags 11 so that it forms a fluid tight chamber between the housing and the bottom and top openings of the bags. As shown, housing 12 has a holddown bar 13 to held hold lid 1 in closed position (when hydraulic lasting pressure is applied), rim ledges 14 which support quick clamps 9, runner guide bar 15 which guides lid 1 in sliding up and down, hydraulic fluid inlet 17, a solenoid controlled hydraulic fluid exhaust 18 which releases the hydraulic pressure after lasting is completed and a sealed top 19 which completes the fluid seal when the top of lasting bags 11 are sealed by mounting rims 20.

The operation of the bag lasting apparatus of this invention is quite simple and best illustrated in connection with FIGURES 1 and 2, described above, which show the apparatus in an open position ready to receive a pair of lasts and shoes to be lasted. The embodiment shown has two pins 4, other similar machines may have 4, 6, 8, or more pairs of pin and lasting bag units. The operator places the unlasted shoes on last 26 and then places them on pins 10. Pressing starter button 31 causes the automatic cycle to begin; pin cylinder 16 is lowered by pins 10 into lasting position at, or near, the bottom of lasting bags 11. Lid 1 is pulled downward by hydraulic cylinder 2 and pistons 3 thereby causing the lid to slide forward and wedge under lid holddown bar 13. Quick locking clamps 9 are automatically pushed into locking position over lid 1 by activating clamping cylinders 5. A hydraulic fluid, such as air, is introduced through a valve controlled inlet 17 until a predetermined pressure of about 50 to 100 p.s.i. is reached. The pressure forces the specially molded lasting bags 11 to uniformly gather and last the entire periphery of the shoe in the lasting pocket. The solenoid controlled exhaust 1S releases the hydraulic fluid when a predetermined lasting pressure is reached, clamps 9 automatically open and lid 1 is raised to its open position by cylinder 2 and pins 4 are raised by cylinder 16 to eject the lasted shoe or position them for manual removal. The shoes are not shown in FIGURES 1 and 2, but their position is easily visualized from the description.

FIGURE 3 shows an enlarged sectional view of a preferred embodiment of the fluid tight pin guide way 22 which maintains a fluid seal between housing 12 and the bottom opening of the lasting bag thereby forming part of the hydraulic fluid pressure area 23 and providing a pathway 22 for the moving pin 10. The sealed pin path 22 consists of a threaded pin pathway area 28 mounted in a mating threaded opening in the bottom wall of housing 12. A corresponding form fitting bottom opening 29 in lasting bag 11 is sandwiched between the bottom wall opening of housing 12 and a retaining nut 24 which preferably has an annular sealing ring or sealing gasket. A second similar retaining nut 30' is preferably positioned below the bottom wall opening of housing 12 to provide a stronger fluid seal which will withstand the high pressures encountered during the lasting step. The position of the fluid tight seal, the pin guide 22 and the sealing lid allows one to modify the design of the apparatus of this invention with a suitable pin connecting bar so that a plurality of pins similar to pins 10 may be controlled by a single hydraulic pin cylinder 16.

FIGURE 4 shows a shoe upper 41 having an adhesively coated extended periphery 42 that is to be folded over, positioned and pressed by lasting bag 11 onto the adhesively coated outer periphery 43 of insole 44. The insole 44 and the shoe upper are positioned on last 26 in the manner shown in FIGURE 5, with the lasted shoe 27 having a lasting or extended portion 43 bound to insole 44. The staple 45 is the conventional means of properly aligning the shoe upper portions for placement on the last.

The elastomeric lasting bags used in the lasting apparatus of this invention must be able to withstand lasting pressures between 50 and psi. In order to withstand the lasting pressure the lasting bags must be specially designed because the lasting bags used by prior art bag lasting machines do not have the strength, flexibility and last-conforming attributes to gather and form an adequate band. Lasting bags having walls thick enough to withstand this pressure are not flexible enough to properly last the periphery of the shoe. To overcome the defects inherent in prior art lasting bags an important feature of this invention is to use a molded elastomeric lasting bag which may be formed on a pattern or core, such as a wood form having substantially the same form or shape as the shoe uppers of the shoes to be lasted. Various known bag forming techniques can be employed to make the bag, for example dip coating or spray coating processes can be used. Dotted line 61, shown in FIGURE 6, indicates the dividing line between that part of the bagforming mold which corresponds to the last for the shoe and the remainder of the mold; and shows inwardly curved portions at locations corresponding the lasting position of the heel and toe of the shoe to be lasted. By so molding the bottom portion of the elastomeric lasting bag, the bottom portion is shaped in the form of a shoe upper and adapted to receive the last and preassembled shoe to be lasted, the remaining portion of the bag walls extends upwards and desirably has inwardly

curved portions

64 and 65 which facilitate gathering and lasting in the toe and heel portions of the lasting bag. Thinner walls in the toe and heel area of the bag wall could also facilitate gathering and lasting in these areas, but this would reduce the life of the bag. With either the inwardly curved wall portion of the thinner wall at the toe and heel areas of the lasting there is a more rapid response to hydraulic pressure in these areas and a more effective gathering of the overlapping material to be lasted. The base 19 when properly fitted to the metal case or housing 12 forms the fluid tight top shown in FIGURE 1. The inwardly

curved portions

64 and 65, and the relatively high walls 62 of lasting bag 11 are important features of this invention. The high walls 62 insure that the bag sides press downward and not only against the sides of the shoe being lasted.

The elastomeric materials used to form the lasting bags may be any stable elastomeric material, such as polyurethanes, polyvinyl chloride, rubber, etc.

Premolded bags 11 are formed to fit a specific shape and shoe size range in order to obtain the high quality last. If one desires to change the shoe style or size range, the operator can readily replace the lasting bag in the apparatus with the proper style and size lasting bag required. Lasting bag interchangeability helps to make the use of this apparatus very flexible and relatively few bags are required for a given shoe style because one bag can handle many sizes.

The relatively high operating pressures required when a plurality of shoes are to be lasted per cycle requires that the housing 12 and the specific lid sealing means used be sturdy, that a bag sealing means similar to the one disclosed above be used to hold the lid in place while the hydraulic pressure required for complete lasting is applied to the plurality of lasting bags within the housing.

The specific lid actuating mechanism disclosed allows one to achieve the unusually fast lasting cycles disclosed herein, but other lid actuating mechanisms may be used.

The bag lasting machine of this invention herein de scribed operates on an automatic cycle once the starter button is pressed. This automatic cycle is readily controlled using known standard hydraulic valve arrangements. Whenever a less expensive version of this machine was desired, each step of the lasting cycle described above could be manually controlled, or the machine may have only one lasting unit instead of the plurality of lasting units described. Although manual and single lasting unit machines are cheaper to construct, their use is definitely less desirable because the cost savings is more than counterbalanced by increased operating costs per shoe produced.

The hydraulic fluid inlet should be so positioned that the entering fluid does not hit the bag because the fluid flow may cause bag erosion. The arrows shown in FIGURE 2 represent lines of pressure pressing against the shoe. Pressure exerted on surface 6 3 of the last forces the last and the pin to the right, this serves to help lock the pin in place preventing it from rising upward in the lasting bag. Releasing the pressure unlocks the pin and facilitates its being raised by the pin cylinder to complete the lasting cycle. The use of supplementary air exhausts to increase the hydraulic pressure release and thereby increase the speed of the cycle is desirable.

In spite of the higher pressures the machines of this invention must withstand (50 to 100 psi.) one obtains faster production cycles, higher quality lasts and greater production per cycle than one would obtain using prior art partial bag lasting machines (approximately 30 p.s.i.).

The simplicity and low cost of this machine, its cost being less than of the combined equipment previously used in the prior art, render it a necessary and desirable machine for use in shoe manufacture. Very few bag sizes are required to accommodate large size differences. I have found that two bag sizes adequately accommodate a run of 24 gradients; or specifically, shoes from the size 8% children through size 7 for young men.

What is claimed is:

1. An apparatus for lasting a plurality of shoes comprising a plurality of elastomeric lasting bags, each of said lasting bags having a bottom opening to accommodate a movable lasting pin, a top opening for receiving shoes to be lasted, a lasting pin, means to move said lasting pin into lasting position in side of said bag and then out of said bag to eject a lasted shoe and receive another shoe to be lasted, a rigid hollow housing arranged about said lasting bags and having a fluid-tight attachment with said bottom and said top openings of said lasting bags so as to provide a fluid-tight chamber between said housing and said lasting bags, means to apply and release hydraulic pressure in said fluid-tight chamber be tween said housing and said lasting bags, and a lid having opening and closing means to cover the top of the said housing and said top openings of said lasting bags during the hydraulic pressure lasting step and uncover said lasting bag top openings during the pin ejection and pin reloading steps.

2. The apparatus of claim 1, wherein the lower portion of said elastomeric lasting bags are molded to conform to the shape of the shoe upper and have a weakened periphery in the portion of the lasting bag that presses against the periphery of the shoe to be lasted.

3. The apparatus of claim 1, wherein the lower portion of said elastomeric lasting bags are molded to conform to the shape of the shoe upper and have inwardly curved portions in the toe and heel areas of the lasting bag to facilitate gathering and lasting in these areas.

4. The apparatus of claim 1, wherein said lid opening and closing means is a hydraulic cylinder that has a piston attached to the upper edge of said lid, the lower edge of said lid being free, said piston being positioned so that when it is an up position said lid is in a standing position above said housing and when said piston moves dOWnward said upper lid edge slides downward and said free lid edge slides over said top openings of said lasting bags.

5. The apparatus of claim 3, wherein supplementary holddown means are provided to help hold the lid closed during the hydraulic pressure lasting step.

6. The apparatus of claim 1, wherein said means to move said lasting pins is a hydraulic cylinder.

7. An elastomeric lasting bag comprising an elastomer lasting bag having a bottom portion shaped in the form of a shoe upper and adapted to receive a last and shoe, walls extending upwards from said bottom portion of said lasting bag, said extending walls having inwardly curved portions in the toe and heel areas of the lasting bag wall to facilitate gathering and lasting in the toe and heel portions of the lasting bag.

References Cited UNITED STATES PATENTS 1,731,0 24 10/1929 Richardson .12 1 1,895,941 1/1933 Ritchey 12 1 X 2,410,878 11/1946 Harrington 121X 2,489,643 11/1949 Hunter 121X 2,996,739 8/1961 Vdolek 12-1 X 3,160,899 12/1964 Bille etal. ,.12 1

PATRICK D. LAWSON, Primary Examiner.

Claims

1. AN APPARATUS FOR LASTING A PLURALITY OF SHOES COMPRISING A PLURALITY OF ELASTOMERIC LASTING BAGS, EACH OF SAID LASTING BAGS HAVING A BOTTOM OPENING TO ACCOMMODATE A MOVABLE LASTING PIN, A TOP OPENING FOR RECEIVING SHOES TO BE LASTED, A LASTING PIN, MEANS TO MOVE SAID LASTING PIN INTO LASTING POSITION IN SIDE OF SAID BAG AND THEN OUT OF SAID BAG TO EJECT A LASTED SHOE AND RECEIVE ANOTHER SHOE TO BE LASTED, A RIGID HOLLOW HOUSING ARRANGED ABOUT SAID LASTING BAGS AND HAVING A FLUID-TIGHT ATTACHMENT WITH SAID BOTTOM AND SAID TOP OPENINGS OF SAID LASTING BAGS SO AS TO PROVIDE A FLUID-TIGHT CHAMBER BETWEEN SAID HOUSING AND SAID LASTING BAGS, MEANS TO APPLY AND RELEASE HYDRAULIC PRESSURE IN SAID FLUID-TIGHT CHAMBER BETWEEN SAID HOUSING AND SAID LASTING BAGS, AND A LID HAVING OPENING AND CLOSING MEANS TO COVER THE TOP OF THE SAID HOUSING AND SAID TOP OPENINGS OF SAID LASTING BAGS DURING THE HYDRAULIC PRESSURE LASTING STEP AND UNCOVER SAID LASTING BAG TOP OPENINGS DURING THE PIN EJECTION AND PIN RELOADING STEPS.