US2566686A

US2566686A - Last for rubber footwear

Info

Publication number: US2566686A
Application number: US744358A
Authority: US
Inventors: Vlcek Alois
Original assignee: BATA NARODNI PODNIK
Current assignee: BATA NARODNI PODNIK
Priority date: 1944-02-03
Filing date: 1947-04-28
Publication date: 1951-09-04
Anticipated expiration: 1968-09-04

Description

A. VVLCEK Sept. 4, 1951 LAST FOR RUBBER FOOTWEAR 3 Sheets-Sheet 1 Filed April 28, 1947 ffl ,ffl Il Sept. 4, 1951 A. vLcEK 2,566,686

LAST FOR RUBBER FOOTWEAR FiledvApril 28, 1947 s sheets-sheet 2 4/0/5 /zcf/f/ Afro/Q fr Sept. 4, 1951 Af vLcEK 2,566,686

LAST FOR RUBBER FOOTWEAR Filed April 28, 1947 3 Sheets-Sheet 5 Patented Sept. 4, 1951 LAST FOR RUBBER FOOTWEAR Alois Vlek, Frystak, Czechoslovakia, assignor to Bata, narodni podnik, Zlin, Czechoslovakia Application April 28, 1947, Serial No. 744,358 In Germany February 3, 1944 Section 1, Public Law 690, August 8, 1946 Patent expires February 3, 1964 6 Claims. (Cl. 18--46) This invention has for its object to facilitate the work when lasting-cil footwear, particularly high rubber boots from the last of a vulcanising mould in which the last also forms the core of the mould.

When pressing a rubber boot this last or core is surrounded by a loi-partite or multiple outerV 'boot has a. temperature of more than 100 C. and sticks tothe last. Therefore with the usual lastv ing-oil by hand it has been necessary to apply considerable force and to protect the hands of the operator by suitable means such as special gloves.

To facilitate the lasting-off it has been proposed to' make the tip or the heel portion of the last detachable, so that this portion remains in vthe interior of the boot when the latter is pulled oil the last, yand has to be withdrawn and replaced on the last for the next pressing operation. VIn this way the lasting-off is only partly facilitated because the pulling-off of a high boot from the non-detached calf portion of the last is still diilicult and, moreover, the handling of the detachable and hot tipor heel-portion of the last is involved and time consuming.

According to the present invention these disadvantages' are overcome in that the boot last is dividedk into portions in a plane such that by relatively shifting 4the said portions the foot of the'last is'shortened and simultaneously the periphery of the calf is reduced. This relative' shifting, which is conveniently performed mechanically, brings about a complete detachment ofthe boot from the last; moreover, when pulling the boot oi, the tip of the last can be tilted in known manner so that the boot can be very easily removed.

Preferably the easy and quick mutual shifting of the separate last portions is assured by a suitable guide on which these portions are shiftably arranged and which is engaged directly on an arm capable of being swivelled. This swivellng arm then allows an effortless transfer of the heavy last either into the vulcanising press or to a position above a driving device which effects the mechanicalV relative shifting of the separate last portions along the aforesaid guide when lasting-off a finished boot.

By way of non-limitative example an embodiment of the invention Vis shown on the accom- 2 Y panying drawings to which reference will now be made.

Fig. 1 is a cross-sectional view of a last for high rubber boots, the dotted lines representing the movable part of the last in the shifted' position with the tip tilted up.

Fig. 2 is a corresponding plan, partly in cross section through the calf portion of the last.

Fig. 3 is a side view of the last pushed into the vulcanising press by means of swivelling arms.

Fig. 4 is a top view corresponding to Fig. 3 showing a double arrangement of swivelling arms with boot lasts in connection with a vulcanising press.

As shown in Fig. l two relatively shiftable last portions I, I' are arranged onl a guide 2' extending upwards from a carrier 2. A spring loaded bolt 3 is shiftably housed vin the guide 2 and abuts with its one end against the movable last portion l whereas its other end connects the stationary last portion I with the guide 2. The movable last portion I', which `conveniently has a tiltable tip I9, is equipped at its inner side with a toothed rack meshing with a pinion 4 which in turn meshes with the external rack teeth of a cylindrical internally.screw-threaded nut 5 which is secured against turning by a feather 6. This nut 5 engages a screw-threaded spindle 8 which carries at its lower end a pinion I in mesh with another pinion 9 having driving slots or dogs 9. These driving slots or dogs 9 aredesigned for a driving member I II (Fig. 3) which transmits the drive from an electric motor I3 through a clutch I2. A hand lever I5 admits the correct movement of the last which is carried by swivelling arms- IB, I1 (Fig. 4), when inserting it into the press and when withdrawing it from the latter to the lasting-off position. In the lasting-off position the aforesaid driving member I0 engages'the slots 9 of the pinion 9, whereupon the clutch I2 can be engaged by means of a hand lever I4 in order to perform the mechanical lasting-oitof the finished pressed boot. Conveniently, the switching on and off of the electric motor I3 is effected by means of a pedal (not shown).

The-manner of operationis as follows;

After the termination of the vucanisation of the boot and the opening of the mould, the control lever 55 (Fig. 3) is gripped and the last is brought out of the press into the lasting-off position which is for example assured by spring loaded bolts I8 engaging dimples in the carrier 2, and thereby the driving member I0 of the clutch I 2 is engaged with the pinion 9. Thereupon the second last (Fis. 4) can be inserted immediately into the press together with the lprepared boot for the purpose of vulcanisation. Thus, by the double arrangement of the swivelling arms l5, il with two'mould lasts there is achieved a considerm able shortening of the idle periods of the vulcanising press. By depressing a pedal (not shown) the electric motor I3 is started and thereby the aforesaid lasting-off device set into motion. The threaded spindle 8 (Fig. 1") of the rst last pulls the nut downwards and .theflatter sets the pinion i in anticlockwise rotation. Thereby the movable last portion i is shifted upwards until it gets into the position ,indicated in dotted lines. In this manner a shortening of the foot of the last as well as a reduction cf the periphery of the calf is brought about Yand at the same time the boot sticking to the last is detached from the latter. By releasing the aforesaid pedal the electric motor i3 and with it the lasting-off device is brought to a stand-still, whereupon the boot can be gripped with the hands and pulled loff without any particular effort in an upward direction, the pivoted last tip i9 being tilted in the process. The last, thus bared, is fitted with a new boot lining and is lbrought into the initial position by starting the electric motor in the opposite direction, and can'be inserted again into the pressafter the completion of the `preparation for the pressing of a new boot. The clutch l2 is conveniently designed so that it can compensate vby slipping for any irregularties or inadvertence when switching the electric motor on and ofi.

It will be apparent from the foregoing and from the drawings that the division of the last in a` plane that runs from the heel -obliquely towards the shin portion is a particularly convenient mode of realising the object of the invention. `However, it -is possible also to arrange the partition plane Iin other ways in order to achieve a shortening of the vfoot of the last as well as a reduction of the periphery of the calf upon relative shifting of the last portions.

An advantageous feature of the invention is that the mutual shifting of the last portions is effectedV `by means of transmission elements housed within the last proper.

VI claim:

1. In a last for a vulcanizing mold press for use in the manufacture of rubber-like footwear, a last divided into separate relatively shiftable portions 4in aplane extending obliquely from the heel forward -towards the shin portion and coupling means extending within and between said portions whereby said portions are adjustable Afor the purpose of enabling the vfoot of the last to be shortened and the periphery of the calf of the last to be reduced when lasting off a workpiece, said coupling means including an intermeshed rack and pinion wholly enclosed bysaid shiftable portions :and by which said shiftable portions may be adjusted in relative position.

2. A last as ,set forth in claim 1, in which the coupling means also includes gearing vfor operating said intermediate rack and pinion for eifecting relative shifting of the last portions, a guide supporting the last, swivelling arms carrying Jhe guide whereby alternately the last can be brought to a preparatory and lasting off position and inserted in a press, a power` unit for operating the said gearing, and means connecting the power unit and the gearing in the said preparatory and lasting oi position of the last.

v,3. In `a last yfor Va vulcanizing mold press for u se in the manufacture of rubber-like footwear, a last divided into separate portions, the said por= tions being divided into a plane and relatively 4 and mechanically shiftable with respect to each other for the purpose of lasting-off a workpiece, ,shortening the foot of the last and simultaneously reducing the periphery of the calf of the last, gear means located adjacent the base of said portions for displacing one of said portions with respect to the other, a guide supporting the relatively shiftable last portions, and a pair of swivelling jointed arms extending between a press and said guide, whereby the last may be alternately moved to a preparatory and lastingoff position and inserted in the press.

4. In a last for a vulcanizing mold press for use in the Vmanufacture of rubber-like footwear, `a last divided into separate portions, the said vportions being divided in a plane and relatively and mechanically shiftable with respect to each other for the purpose of lasting-off a workpiece, shortening the foot of the last, and simultaneously reducing the periphery of the calf ofthe last, gear means located adjacent the base ofsaid portions for displacing one of said portions with respect to the other, a guide supporting the last, swivelling arms carried by the guide for .alternately moving the last to a preparatory and -:lasting-olf position and for insertion in a press, a power unit for operating the gear means, Land means for coupling the power unit and the gear means in the said preparatory position and lasting-olf position of the last. v

5. In a last for a vulcanizing mold lpress for use -in the manufacture `of'rubber.'lilze footwear, a last divided into separate portions, the said-portions being divided in a plane and relatively and mechanically shiftable with respect to each other for the purpose of lasting-off a workpiece, shortening the foot of the last, and simultaneously reducing the periphery of the calf of the last, Ygear means located adjacent the base of said portions for displacing one of said portions with `respect to the other, a guide supporting said relatively shiftable last portions and gearing for operating said gear means for effecting relative shifting of the last portions.

6. In a last for a vuloanizing'gmold'press for use in the manufacture of rubber-like footwear, a last divided into separate portions, the said por# ltions being divided into a Aplane and relatively `and mechanically Shiite-ble with respect to each other for the purpose of lasting-off a workpiece, shortening the foot of the last, and simultaf Aneously reducing the periphery of the calfof the last, gear means located adjacent the base of said .portions for displacing one of said portions `with respect to the other, in which the relative shiftable 'last portions are supported by a guide and a s et of ntermeshing coplanar gears housed by said guide for operating said gear means, said gear means including a screw for effecting vrelative shifting of the lastportions.

VLCEK, vmois- REFERENCES CITED v The following references are of record in the 'file of this patent:

'UNITED STATES 'PATENTS