US2635265A - Collapsible last - Google Patents

Description

April 21, 1953 A. w. MCNEILL COLLAPSIBLE LAST Filed 001;. 1. 1952 IN V EN TOR. M 20/141141 Fig. 2

Patented Apr. 21, 1953 UNITED STATES PATET OFFICE COLLAPSIBLE LAST Alexander W. McNeil], Lynn, Mass.

Application October 1, 1952, Serial No. 312,475

8 Claims. 1

This invention comprises a new and improved last having novel hinge or looking characteristics which adapt it particularly well for use in the slip lasted process of shoemaking although they may be embodied with advantage in other types of last.

In the manufacture of slip lasted shoes it is the practice to spindle the last on a vertical pin and to swing its forepart upwardly into an approximately 45 position as being the most convenient for pulling the upper into position upon the last preliminarily to straightening the last and placing the upper under severe tension. The operation of pulling the upper over the forepart of the last is usually carried out by a powerful operator who exerts such a strong pull upon the forepart of the collapsed last that frequently a section is split out of the bottom of the last or the plates of the last hinge are caused to cut through the wooden bottom of the last.

The principal object of the present invention is to provide a last in which the fo-repart will be supported in upwardly inclined collapsed position in such a manner that the wood in the bottom of the forepart is not subjected to excessive splitting strain. The invention further contemplates a construction which will permit quick and substantial shortening of the last when it is collapsed in order that it may be withdrawn easily from the upper without undue strain.

In one aspect my invention is characterized by last hinge mechanism including a retaining latch which is automatically engaged when the last is collapsed and which transfers to its own metal parts all or a substantial portion of the strain caused by the powerful pull of the operator increased in magnitude by the leverage of the forepart. As herein shown and in accordance with an important feature of the invention the retaining latch is secured to or formed as a part of a tension link which units the parts of the last.

As herein shown the last is provided with a pivoted latch link which is arranged to engage an abutment of the retaining latch when the last is collapsed and to engage a latch pin when the last is straightened and in this latter position to hold the two parts of the last rigidly in straightened condition.

Another essential requirement of a satisfactory last is that the operation of locking and unlocking the last should be effected instantaneously. This is effected in the improved last of my invention by swinging the latch link through the few degrees necessary to disengage it from the latch pin. For this purpose the head of the latch link is rounded and brought into an open space adjacent the cone of the last where it is readily accessible by the operator or by the releasing element of a jack.

Going more into detail, the last hinge plates of my invention include a pivoted latch link herein shown as anchored in the forepart of the last and extending diagonally and upwardly into position to engage a stationary latch pin located in the top of the heel part. So long as the latch link is engaged with this pin it cooperates with the tension link to hold the last parts rigidly in extended or straightened position. When the latch link is released from the last pin the forepart is free to swing upwardly and to move rearwardly so that the last is immediately shortened. At the same time the latch link moves automatically into engagement with the latch abutment of the tension link thereby limiting the swing of the forepart and taking up in itself any excessive pressure that may be exerted upon it. When the forepart of the last is returned to its straightened position the latch link automatically disengages itself from the retaining latch of the tension link and returns automatically to engagement with the latch pin.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which:

Fig. l is a view in elevation partly in section of the last in collapsed position,

Fig. 2 is a similar view showing the main portions of the last in extended position, and

Fig. 3 is a plan view of a tension link of modified construction, a portion being broken away.

The last herein shown comprises a forepart l9 and an interfitting heel part H. The mating faces of these parts are complementary to each other except at the cone of the last where they are separated to provide an open space into which the operating end of the latch link projects so that it may be unlatched for collapsing the last. The heel part I I is provided with a slot or mortice I2 and in the mating face of the forepart is formed a registering slot 13 in which the metal connecting mechanism is housed. The mating faces are transversely shouldered at an intermediate point to form interlocking engagement when the last is extended and the slot I2 is so shaped as to leave a stout shoulder ll adjacent to the tread surface of the heel part.

The connecting mechanism comprises an elongated tension link M which as herein shown may.

be made up of two identical spaced members longitudinally curved and slotted. They are provided with an anchor pin IS in the forepart and an anchor pin I! in the heel part of the last. These links are disposed in the lower portion of the last and are themselves the subject matter of my prior Patent No. 2,188 414, granted January 30, 1940, although they are herein shown as employed in a new combination and in new shape. The tension link is pivoted upon its rear end to swing about the anchor pin I! while the anchor pin it is received in the slot of the link so that the pin it may move rearwardly in the slot with lost motion when the last is collapsed.

In its upper side adjacent to the anchor pin I! the link is shaped to provide in its upper edge a sharp latch angle or abutment l5. The contour of the tension link end of this latch abutment is duplicated in an intermediate plate 2| which is located between the identical members of the tension link and spot welded in place thus producing a strong flat unit having a pronounced latch angle of three ply thickness. For example, the spaced members of the link may be 0.058 in thickness while the intermediate plate 2| may be 0.0937'5 in thickness. The tension link unit fills the slots l2 and I3 in the last parts with a freely sliding fit and may be limited in its swinging movement by the shoulder l I of the heel part when the last is collapsed to the limit of its movement.

A bowed latching link i9 is pivotally mounted upon the forepart anchor pin it: and arranged to swing in the slot l3 of the forepart and between the two members of the tension link. Its outer end is rounded and hook shaped to fit either the latching abutment [5 of the tension link or a latching pin l8 set in the upper portion of the heel part. It has an externally rounded edge surface so that it may be readily engaged by projecting a wedge upwardly into the space between it and the inner face of the heel part of the last and also so that it will cam itself forwardly and snap over the latch pin l8 when the last is straightened. The link 19 is bowed so that it may flex and lengthen slightly to relieve the last of improper excess pressure if the last should be mistreated in use. A curved leaf spring '20 is held in the slot I3 against the back of the latch link l9 and this tends always to swing the link into one or the other of its latching positions.

The side members of the tension link It are curved and longitudinally slotted so that they are flexible and can elongate slightly if necessary in bringing the two parts of the last into its extended position as shown in Fig. 2. In Fig. 3 is shown an alternate form of tension link in which the two side members 22 are solid except for the perforation to receive the anchor pin ll of the heel part and a short slot to receive the anchor pin l6 of the forepart. The latch plate 2| is assembled between these two parts and spot welded in place to form a rigid unit that presents a three ply latch angle or abutment. The link of Fig. 3, therefore, provides a somewhat stouter construction that may advantageously be used in lasts of the larger sizes or wherever particularly heavy work is to be encountered.

The action of the connecting mechanism in holding the parts of the last in extended position will be apparent from an inspection of Fig. 2. The tension link l4 holds the parts of the last against longitudinal separation. The trans verse shoulder in their mating surfaces positively prevents the forepart from moving downwardly with respect to the heel part, and the latch link [9, by its engagement with the latch pin l8, positively prevents movement of the forepart in the opposite direction.

When the latch link I9 is disengaged from the latch pin l8, the forepart is immediately free to swing upwardly on substantially the radius of the mating faces. However, by the time that the rear end of the forepart engages the tread face of the heel part, as shown in Fig. 1, the latch link is has engaged the latch abutment l5. Since the distance between the anchor pin [6 and the latch abutment [5 in the extended position of the last, as shown in Fig. 2, is slightly greater than the effective length of the last link [9, the anchor pin it must travel slightly along the slot of the tension link in order to permit the latch link to engage the abutment 15. In this latching movement the latch link I9 is under tension, and it is the tension in the link H3 in cooperation with the pressure of the heel part against the rear end of the forepart that sup--v plies a balanced and effective force in resistance to rearward stress upon the toe portion of the last. Resistance to further rearward movement of the forepart may be increased by designing the shoulder ll of the heel part to engage the underside of the tension link M in the extreme collapsed position of the last, but this is usually not necessary, and if so, the shoulder is never subjected to objectionable strain on account of the other forces which the connecting mechanism brings into play.

Having thus disclosed my invention and de scribed in detail a preferred embodiment there-: of, I claim as new and desire to secure by Letters Patent:

1. {a collapsible last having heel and foreparts with mating contact surfaces, an anchor pin in each part of the last and a tension link connecting said pins, together with a latch plate secured to the tension link and having a latch abutment therein, and a latch link pivoted to one of the anchor pins and shaped to engage said abutment when the last is collapsed.

2. A collapsible last having heel and fore: parts with mating contact surfaces, an anchor pin in each part of the last and a tension link connecting said pins, a latch pin in the heel part, a latch abutment on the tension link, and a latch link pivoted on the anchor pin of the forepart and shaped to engage either the latch pin or the latch abutment of the tension link.

3. A collapsible last comprising heel and foreparts with mating surfaces, an anchor pin in each part of the last and a tension link connecting said pins and composed of spaced side members enclosing between them a latch plate having an angular abutment, a latch link pivotally mounted on the anchor pin of the forepart and movable into engagement with the abut-v ment of the latch plate when the last is 001.- lapsed, and a latch pin in the heel part of the last which is also engageable by the latch link.

4. A collapsible last comprising heel and force parts, and connecting mechanism including a tension link with a projecting latch angle in its contour, a latch link engageable therewith, an anchor pin in the heel part for the tension link, and a common anchor pin in the forepart forthe tension link and the latch link.

5. A collapsible last comprising heel and fore.- p rt an c nn n m c an m inc udin a 5 flexible tension link anchored at its opposite ends in the respective parts of the last and carrying a projecting latch abutment in its upper side, and a latch link pivotally mounted in the forepart and shaped to engage said abutment when the last is collapsed.

6. A collapsible last comprising mating heel and foreparts, a double tension link having spaced side members extending between the respective parts of the last, an anchor pin at each end of the tension link, the said link having a slotted lost motion connection with the anchor pin in the forepart of the last and presenting a latch abutment in its upper side, a latch plate fastened in place between the side members of the tension link at its heel end and conformed to the contour of the latch abutment, a latch link pivotally mounted on the anchor pin at the forepart end of the tension link and shaped to engage the latch abutment when the last is collapsed and having a curved head, a latch pin located above the tension link in the heel part in position to cam the head of the latch link into engagement therewith when the last is straightened, and a spring for assisting the engaging movment of the latch link.

7. A collapsible last comprising mating heel and foreparts longitudinally slotted and transversely shouldered in their mating faces, a tension link anchored at its opposite ends in the respective parts of the last and having a latch projection in its contour which is located Within the slot of the heel part, a latch pin in said heel part, and a latch link pivotally mounted in the forepart and shaped to engage the said latch projection when the rear end of the forepart is brought into contact with the tread face of the heel part thereby resisting rearward pull upon the toe end of the forepart.

8. A collapsible last comprising heel and foreparts with mating surfaces, an anchor pin in each part of the last and a tension link connecting said pins and comprising spaced side members both having a projecting latch abutment and enclosing between them a latch plate having a similar latch abutment, the two side members and the latch plate together presenting a solid three ply latch abutment, a latch link pivotally mounted on the anchor pin of the forepart and movable into engagement with the said abutment when the last is collapsed, and a latch pin in the heel part of the last which is also No references cited.

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