US2315676A - Shrinking machine - Google Patents

Description

April 6, 1943- r I A. E. USHAKOFF ,3

SHRINKING MACHINE Filed June 19, 1941 3 Sheets-Sheet l April 1943- A. E.VUSHAKOFF 2,315,676

SHRINKING MACHINE Filed J1me 19, 1941 3 Sheets-Sheet 2 Apiil s, 1943.

A. E. USHAKOFF SHRINKING MACHiNE Filed June 19, 1941: 3 SheetsSheet 3 III Patentecl Apr. 6, 1943 SHRIN KING MACHINE Alexis E. Ushakoif, Beverly, Mass, assignor to 'United Shoe Machinery Corporation, Flemington, N. J a corporation of New Jersey Application June 19, 1941, Serial No. 398,773

(Cl. lit-49.1)

18 Claims.

This invention relates to machines for causing a hollow blank to shrink about an article and is herein illustrated as embodied in a machine for causing a hollow blank to shrink about a heel so as to form a permanent cover therefor.

In Letters Patent of the United States No. 2,236,552, granted April 1, 1941, upon an appli cation filed in my name, there is disclosed a hollow heel-cover blank made of macromolecular material in the form of a swollen gel which is capable of stretching and will shrink by loss of liquid. There are described in said Letters Patent two methods of using such a blank to cover a heel. According to one method, referred to therein as the wet method, the heel is placed in the blank which is then caused to shrink about it. According to the other method, referred to therein as the dry method, a block of circular outlines is placed in the mouth of the cover blank while the blank is in swollen gel form, and the blank with the block in its mouth is put aside and allowed to shrink, the function of the block being to keep the mouth open and of a desired size, a machine for inserting such a block being disclosed in Letters Patent of the United States No. 2,296,964, granted September 29, 1942, upon an application filed in my name. The blank is then expanded by means of heat and pressure and frozen in expanded shape, a machine for so treating a blank being disclosed in application Serial No. 392,482, filed May 8, 1941, in my name. Finally a heel is placed in the blank and the blank is heated and a partial vacuum is created in it to cause it to shrink and conform to the shape of the heel.

According to the present invention a machine is provided comprising a carrier for a hollow blank which contains an article about which it is to be shrunk, a shrinker, and means for producing relative movement of approach between the carrier and the shrinker to cause the hollow blank to be acted upon by the shrinker. In the illustrated machine the mouth of the blank is clamped to the carrier, and the blank with its contained article is lowered into a shrinker in the form of a heater. In order to cause the blank to conform to concave surfaces of the article, a partial vacuum is created in it during the shrinking operation.

When a hollow blank is to be shrunk about an article such as a heel to form a permanent cover therefor, it is desirable that the shrunken cover should extend over upon the margin of that face of the article which is adjacent to and exposed by the mouth of the b1ank-the attaching face of a heel. To this end, in accordance with another feature of the invention, the mouth of the blank is clamped to the carrier; the suction which creates the partial vacuum in the blank is so applied that it tends to move the body portion of the blank toward the carrier, and this movement is yieldingly resisted with the result that the portion of the blank between its mouth and the'adjacent face of the article bends inwardly over said face.

According to a further feature of the invention the article in the hollow blank is held from movement during the shrinking of the blank about it, this being accomplished in the illustrated machine by a member supported by the carrier and having a suction cup to engage the article.

These and other features of the invention including certain details of construction and combinations of parts will be described as embodied in an illustrated machine and pointed out in the appended claims.

Referring to the accompanying drawings,

Fig. 1 is a front elevation of a machine in which the present invention is embodied;

Fig. 2 is a side elevation of the machine;

Fig. 3 is a detail, partially in vertical section, showing a construction which permits certain conduits to slide vertically when the blank carrier is raised and lowered;

Fig. 4 is a side elevation, partly in section, showing the slidable cover for the heater and the means for operating it;

Fig. 5 is a vertical section of the blank carrier and the parts associated with it, a hollow blank with its contained heel being shown as clamped to the carrier; and 1 Figs. 6 and '7 are vertical sections showing different stages in the shrinking of a blank.

Referring to Fig. 1, the machine has a carrier which includes a hollow cylinder l0 having rigid with its lower end and fastened in place in a manner presently to be described a hollow block ill] of Bakelite or other poor conductor of heat, said block being adapted to have clamped to it by fingers, presently to be described, the mouth of a cover blank 200 in which a heel has been placed. The whole carrier structure is mounted on an arm I 3 which is fast to the upper end of a vertically reciprocable piston rod IS. The hollow cylinder I0 has vertically slidable through it a suction tube I, having at its lower end a perforated disk I9 of thin, flexible material to serve as a suction cup by engaging the attaching face of a heel I 09 (Fig. 5), which has been placed in a shrinkable cover-blank 290. The principal function of the suction cup i9 is to hold the heel from sidewise or tipping movement during the subsequent shrinking of the cover about it. Directly below the carrier (Fig. 1) is a shrinker in the form of a heater 2!, the open top of which may be closed by a slidable cover 23.

The machine is operated entirely by compressed air and by suction. Compressed air is caused, by depression of a treadle 39, to flow through a conduit 25 to move clamping fingers 21 to the open positions, shown in broken lines in Fig. 5, whereupon a cover blank with a heel in it is presented by the operator to the carrier. At the sam time, compressed air is caused to flow through a conduit 29 (see also Fig. 4) to move the cover 23 ofthe heater to closed position. Release of the treadle then permits the fingers 2! to clamp the hollow blank to the carrier. Next, compressed air is caused to flow through conduits 3i (Fig. 4) and 33 (Fig. l) to slide the cover 23 to open position and to pull down the vertical rod l5 and thus lower the carrier with its cover-blank and its heel into the heater, whereupon the hollow blank is shrunk about the heel; and finally compressed air is caused to flow through the conduit 35 to raise the carrier into the position shown in Fig. 1, ready to receive another hollow blank with its contained heel. Suction is applied continuously, in the direction indicated by the arrow through the tube IT, to cause the suction cup is to operate when the heel-attaching face of the heel is pressed up against it. Suction is also applied through a conduit 31 to create a partial vacuum in the cover-blank.

. Assuming that the parts of the machine are in the positions shown in Fig. l, the operation is as follows. The treadle 39 is depressed. This causes compressed air to flow through the conduit 29 (see also Fig. 4) to close the cover 23 of i the oven, and at the same time causes compressed air to flow through the conduit 25 to swing the fingers 21 away from the carrier (Fig. 5). A hollow blank 26!] with a heel IEO in it is presented to the carrier in such manner that the mouth of the cover extends over the hollow block 1 i ii which forms the lower end of the carrier, and the attaching face of the heel is engaged by the suction cup Hi. The treadle 39 is released, whereupon the fingers 21 clamp the mouth of the cover to the carrier at spaced localities, as shown in Fig. 5. A hand lever 4| (Figs. 1 and 2) is now swung in one direction. This causes compressed air to flow through the conduit 3| to slide the cover 23 of the heater to open position, and causes compressed air to flow through the conduit 33 to pull down the piston rod l5 so as to lower the carrier with its heel and cover blank into the heater. Here, the shrinking of the blank takes place, aided by the suction applied through the conduit 31, as will be described in detail below. When the shrinking is complete, the hand lever M is swung into the position shown, whereupon the piston rod I5 is pushed up and the machine comes to rest with the parts in thepositions shown in Figs. 1 and 2.

Referring to Figs. 5 to 7, the upper end of the cylinder I9 is clamped rigidly to the outer end of a member 45, the inner end of said member being fastened to the arm 13 (Fig. 1). Fastened to the upper portion of the cylinder just below the member 45 is a ring 41, in four depending lugs of which are pivoted at 49 the upper ends of the upper members of the four extensible clamping fingers 21, said upper members carrying pins 5i which are slidable in longitudinal sockets formed in the upper ends of the lower members, said lower members being vertically adjustable on the pins and held in adjusted positions by set screws 53. The upper members have small arms which extend inwardly through slots 55 in the wall of is urged upward at all times by a coil spring iii, the upper end of which contacts with the underside of the block 59 and the lower end of which rests on the bottom of a socket in a member G3, which is threaded into the interior of the cylinder. The hollow block i ii is threaded on the lower end of the member 83. The upper end of the cylinder is closed by a block 65, having a port to receive the delivery end of the compressed air conduit 25; and when compressed air is permitted to fiow into the topof the cylinder through this con-duit, it pushes down the slide block 59 and swings the clamping fingers 21 to open position, as indicated in dotted lines in Fig. 5. The lower ends of the lower members of the clamping fingers 27 have kerfs cut in them to provide somewhat flexible stems 28 at the free ends of which are the workengaging portions; and screws 36, threaded through the rigid parts of the fingers and extending through the kerfs into contact with the stems 23, provide means for adjusting the workengaging portions.

The slender tube H carries at its lower end a small perforated block 61, to the lower inclined face of which'is fastened the perforated flexible disk 59. Near its upper end, the tube I'l carries a collar 69 which is urged at all times into contact with the blocks 65 by a compression spring H, said spring extending between said collar and a horizontal portion of a bracket '53, and said bracket being rigid with the member 45. The block' 63 has two diametrically opposite longitudinal grooves 15 which are in communication both with the interior of the hollow Bakelite block I l0 and with an annular groove from which the suction pipe 31 leads. There is thus free passageway for air up through the hollow block HG, the vertical grooves T5, the annular groove and the suction pipe 31 as indicated by the arrows.

As has been explained, suction is being applied continuously through the tube i1 and through the conduit 37. When the treadle 39 (Fig. l) is depressed to cause compressed air to flow through the conduit 25, so as to swing out the fingers 27, and a heel with its cover-blank is presented with the mouth of the blank about the hollow block H0 and the attaching face of the heel in contact with the disk or suction cup l9, the heel and its blank remain in place due to the suction through the tube 1?. When the treadle is released to cut oil the supply of compressed air, the pressure in the conduit 25 immediately falls because of leakage in the various connections, and the spring Bl swings the fingers 21 to clamp the mouth of the cover at four spaced localities to the carrier, the parts then being in the positions shown in Fig. 5. The whole carrier with its associated parts is then lowered to introduce the heel and its cover-blank into the heater. Thus far, the suction, which is continuously ap plied through the conduit 31 to the interior of the lower portion of the carrier, has no effect upon the cover-blank 2%, since the mouth of the blank is open to the atmosphere at localities between the fingers 21. Very shortly, however, the blank becomes heated sufiiciently to cause it to shrink; and the moment the mouth of the blank shrinks so as to form an air-tight joint around the lower end of the carrier as shown in Fig. 6, a partial vacuum is created in the blank. Thereafter, the combined action of the heat and the partial vacuum causes the hollow blank to shrink about and conform to the heel. When the parts are in the position shown in Fig. 6, the tendency of the partial vacuum is to move up the body portion of the blank and with it the heel so as to create slack in the wall of the blank between the adjacent end of the carrier and the heel, and, since this tendency is resisted to an extent by the spring II, the direction of bend of the portion of the cover between the upper edge oi the heel and the lower edge of the carrier is controlled, said bend taking place inwardly, as shown in Fig. '7, so that portions of the cover are pulled over upon the margin of the attaching face of the heel, as shown in Fig. 7. Finally, the heel is drawn up until substantially only a double thickness of the material of the hollow blank separates it from the bottom of the hollow carrier.

Although the operation of conforming the blank to the heel has been described as though it were a slow one, the reverse is true. Since the oven is maintained at a high temperature, the initial shrinking of the mouth of the blank about the lower end of the carrier. to form an air-tight joint, or one nearly enough so that the partial vacuum begins to form in the hollow blank, takes place in about two seconds; and the final shrinking is practically momentary, the completion of the operation being indicated by a sudden move ment of the pointer on the gage I9 (Fig. 1), which registers the degree of vacuum in inches of mercury. The operation is now complete, the car rier is raised, and the covered heel removed, it

being understood that before the heel is incorporated in a shoe the surplus material of the cover will be trimmed off.

The heater or oven 2i (Fig. 1) may be heated to a temperature in the neighborhood of 800 F. by resistance coils 3|, 83, this temperature depending, of course, upon the thickness of the hollow blank 2E9 and the material of which it is made. The current supplied to the coil 3! may be varied by turning the control member 85 of a variable autotransformer 81, a second such transformer, the rotatable control member of which is indicated at 855, being provided for the coil 83.

Referring now to Fig. l, the suction tube I1, which is vertically reciprocable in the carrier, is connected by a flexible rubber tube 9| to a conduit 93 having a downwardly extending portion (Fig. 3) which is vertically slidable in a station ary hollow member 95, the Vertical portion of the conduit 83 being fastened by a set screw 9'! to a projection on the arm I3, which is carried at the upper end of the piston rod I5. From the lower end of the stationary hollow member 95, a conduit 99 leads from the suction side of a rotary pump IGI (Figs. 1 and 2), the exhaust conduit of which is indicated at I03. The conduit 31. which leads from the side of the carrier, is connected to the suction conduit 93; and both conduits are in communication with the pressure gage T9. The conduit 25 for compressed air also has a downwardly extending portion, not shown, which is directly behind (Fig. 2) the downwardly extending portion of the conduit 83 and is vertically slidable in a stationary hollow member, which is identical with and directly behind the stationary member 95. Into the lower end of this stationary hollow member, which is not shown. a conduit I95 (Fig. 1) leads from a T It! to which compressed air is supplied by forcing down the stem of a valve me in a casing III. Compressed air from a source of supply enters through a conduit I i3, passes through a pressure regulator H and thence through a conduit III; to the valve casing III. The valve I09, which is normally held in raised closed position by a spring, not shown, may be opened by depressing the treadle 39. This pulls down a treadle rod IIT, the upper end of which is pivoted to one end of a small arm I I9, the other end of which is pivoted to a stationary part of the machine. A tension spring 29 normally holds the treaclle 39 in raised position. The T I31, which receives compressed air from the valve casing II I, has also connected to it the conduit 29 (see also Fig. 4); and when compressed air is supplied to this T, it flows also through this latter conduit. Referring now to Fig. 4, the conduit 29 leads to the rear end of a horizontal cylinder I2I, in which is a piston I23 at one end of a piston rod I24, the other end of which is fast to the cover 23 of the oven, the opposite margins of said cover being mounted for horizontal sliding movement in stationary guides I25. Consequently, when compressed air is supplied to the conduit 29, the cover 23 of the oven is moved into closed position.

Referring again to Fig. 1, the means for moving the cover 23 to open position and for reciprocating the piston rod I5 vertically, will be described. rom the pressure regulator II5. which has a pressure gage I21 in communication with it, a conduit I29 leads into the casing I3I of a control mechanism, such that when the hand lever M is swung to one limit of its movement, compressed air flows through the conduit 33 into the top of a cylinder I33 above a piston I35, which is carried at the lower end of the vertical piston rod I5, and the cylinder is exhausted through the conduit 35; and, when the handle is swung to its other limit of movement, compressed air flows through the conduit 35 into the lower end of the cylinder I33 while the upper end of the cylinder is exhausted through the conduit 33. This control mechanism is a well known commercial unit, the details of construction of which form no part of the present invention. The mechanism just described lowers and raises the piston rod I5. It also serves to move the sliding cover 23 of the oven to open position, when compressed air flows through the conduit 33 into the top of the cylinder by reason of the fact (Fig. 2) that the conduit 33 communicates with the conduit 3|, which leads into the forward. end of the horizontal cylinder I21. The frame of the machine consists of uprights I37 and cross-pieces I39 by which the stationary parts are supported.

The operation of the machine is briefly as follows:

Assuming that the parts of the machine are in the positions shown in Figs. 1 and 2, the treadle 39 is depressed. Compressed air is thereby admitted to the conduits 29 and M5. The air flowing through the conduit 29 enters the rear end of the horizontal cylinder I2I (Fig. 4) and slides the cover 23 of the oven to closed position. The air flowing through the conduit Hi5 flows into the bottom of a vertical hollow member, like the member (Fig. 3), and then up through said member and through the conduit 25 (Fig. 5) into the top of the cylinder I9 to push down the sliding block 59 and thereby swing the fingers 21 to open position. A cover blank 290, with a heel I69 in it, is placed with the mouth of the blank over the hollow member II ii at the lower end of the carrier and the suction cup I9 in contact with the attaching face of the heel. The treadle 39 is then released, whereupon the compression spring BI causes the fingers 2"! to clamp the mouth of the heel cover to the member H0. The handle 4| is swung to one limit of its movement, whereupon the sliding cover 23 f the heater is moved to open position and the piston rod l is pulled down to lower the carrier with the heel H and the blank 260 into the heater. Since the blank is one which has been expanded under heat and then frozen in expanded shape, the heat of the heater causes the blank to shrink. As soon as the mouth of the blank has shrunk suiliciently to form an air-tight joint, or one which is nearly so, about the member H0, which forms the lower portion of the carrier, the suction which has been acting continuously through the conduit 3? creates a partial vacuum in the blank, this vacuum being strong enough to pull the heel up against the force of the spring H and to cause portions of the blank to bend inward over the margin 01 the attaching face of the heel and other portions to lie against any concave surfaces of the heel.

The operation is now complete, and the handle 4! is swung back into its original position whereupon the parts of the machine return to the positions shown in Figs. 1 and 2. It will be understood that the cover of the heater is still open, and that the fingers 2'. are still holding the heel and its shrunken cover. When the treadle 39 is depressed-this being the first step in the operation of the machine as described abovethe cover of the heater is closed and the fingers 21 are swung out, so that the heel with its shrunken cover may be removed and a succeeding heel in its unshrunkcn cover presented to the machine.

Although the invention has been described in a heel, with a permanent cover in the form of a thin-walled shell, the invention provides a means for making such a shell of a particular shape by causing a shrinkable blank to take the shape of a form and then removing the shrunken blank from the form. It is thus possible to make such thin-walled hollow articles as may be removed from the forms on which they are made.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. A machine of the class described having in combination a carrier for a hollow blank capable of shrinking and containing an article about which it is to be shrunk, a shrinker, means for producing relative movement of approach between the carrier and the shrinker to cause the hollow blank to be acted upon by the shrinker, and a suction device engaging the article for maintaining the article in position during the shrinking of the blank about it.

2. A machine of the class described having in combination a carrier adapted to be inserted in the mouth of a hollow blank which is capable of shrinking about an article contained in it, means for holding the mouth from movement with respect to the carrier, means for shrinking the blank, means for applying suction through the carrier to the interior of the blank whereby force is exerted to cause the body portion of the blank to conform to the article and to move said body portion together with the article toward the carrier, and yielding means for opposing such movement whereby the wall of the blank between the article and the carrier bends inwardly over that end of the article which is nearest to the mouth as the article moves toward the carrier.

3. A machine of the class described having in combination a carrier adapted to be inserted in the mouth of a hollow blank which is to be shrunk by heat about an article contained in it, means for holding the mouth from movement with respect to the carrier, means for heating the blank, means for applying suction to the interior of the blank in such manner that force is exerted to move the body portion of the blank together with the article toward the carrier, and yielding means for opposing such movement whereby the wall of the blank between the article and the carrier bends inwardly over that end of the article which is nearest to the mouth as the article is moved toward the carrier.

4. A machine of the class described having in combination a carrier adapted to extend into the mouth of a hollow blank in which is an article about which the blank is to be shrunk, means for clamping the mouth to the carrier, yielding means for resisting movement of the article and through it the unclamped portion of the blank toward the carrier, means for causing the blank to shrink, and means for applying suction through the carrier to create in the blank a partial vacuum sulficient to overcome the force of the yielding means.

5. A machine of the class described having in combination a carrier adapted to extend into the mouth of a hollow blank in which is an article about which the blank is to be shrunk, means for clamping the mouth to the carrier at spaced localities, yielding means for resisting movement of the article and the unclamped portion of the blank toward the carrier, means for applying suction through the carrier to the interior of the blank. and means for causing the blank to shrink, whereupon its mouth shrinks about the carrier and the suction creates in the blank a partial vacuum suiicient to overcome the force of the yielding means.

6. A machine of the class described having in combination a carrier for supporting by engagement with its mouth a hollow blank in which is an article about which the blank is to be shrunk, the article being spaced from said mouth, a heater, means for producing relative movement of approach between the carrier and the heater to cause the hollow blank with its contained article to be subjected to the action of the heater, means for creating a partial vacuum in the hollow blank, and yielding means for opposing the movement of the article toward the carrier due to the efiect of the partial vacuum.

7. A machine of the class described having in combination a carrier adapted to extend into the mouth of a hollow blank containing an article about which it is to be shrunk, means for clamping the mouth to the carrier, said clamping means being movable to inoperative position to permit the blank to be presented to the carrier, and a suction tube yieldingly mounted for Sliding movement in the carrier and having a suction cup to engage a face of the article in the hollow blank when the blank with the article in it is presented to the carrier.

8. A machine of the class described having in combination a carrier for a hollow blank containing an article about which it is to be shrunk, a heater, means for causing relative movement of approach and separation between the carrier and the heater to cause the blank to be received in and then withdrawn from the heater, a cover for the heater mounted for sliding movement in a path at right angles to said relative movement of approach, and means for sliding the cover to open position to permit said relative movement.

9. A machine of the class described having in combination a carrier for a hollow blank which is capable of shrinking about an article con tained in it, a shrinker normally spaced from the carrier a distance suflicient to permit the mouth of the hollow blank to be placed over an end of the carrier, clamping means movably mounted on said carrier, means for causing the clamping means to clamp the mouth of the blank to the carrier, and means for producing relative movement between the carrier and the shrinker to cause the hollow blank thus clamped to the car rier to be acted upon by the shrinker.

10. A machine of the class described having in combination a carrier for a hollow blank which is capable of shrinking about an article contained in it, a shrinker normally spaced from the carrier a distance sufilcient to permit the mouth of the hollow blank to be placed over an end of the carrier, clamping means movably mounted on the carrier, means for causing the clamping means to clamp the mouth of the blank to the carrier, yielding means supported by the carrier and extending through the mouth of the blank into engagement with the article, means for pro ducing relative movement between the carrier and the shrinker to cause the hollow blank to be acted upon by the shrinker, and means for applying suction through the carrier to the interior of the hollow blank.

11. A machine of the class described having in combination a carrier for a hollow blank which is capable upon being heated of shrinking about an article contained in. it, a heater normal- 1y spaced from the carrier a distance suficient to permit the mouth of the hollow blank to be placed over an end of the carrier, clamping means movably mounted on the carrier, means for causing the clamping means to clamp the mouth of the blank at spaced locations on the carrier, means for producing relative movement of approach between the carrier and the heater to cause the blank to enter the heater, and suction means for applying suction to the interior of the blank, said suction means acting to create a partial vacuum in the blank when the heat has caused the mouth of the blank to shrink about the end of the carrier.

12. A machine of the class described having in combination a carrier for a hollow blank which is capable upon being heated of shrinking about an article contained in it, a heater normally spaced from the carrier a distance sufficient to permit the mouth of the hollow blank to be placed over an end of the carrier, clamping means movably mounted on the carrier, means for causing the clamping means to clamp the mouth of the blank at spaced locations on the carrier, means for producing relative movement of approach between the carrier and the heater to cause the blank to enter the heater, means for applying suction to the interior of the blank, said suction means acting to create a partial vacuum in the blank when the heat has caused the mouth of the blank to shrink about the end of the carrier, a cover for the heater, and means for opening the cover while the blank is clamped to the carrier and during the relative movement of approach of the carrier and the heater.

13. A machine for operating upon a hollow shrinkable blank having in it an article about which the blank is to be shrunk, said machine having in combination an elongated carrier having an end adapted to be received in the mouth of the blank, fingers mounted in the carrier for clamping the mouth of the blank to the carrier, a shrinker, and means for producing relative movement of approach between the carrier and the shrinker to cause the blank to be operated upon by the .shrinker.

i i. A machine for operating upon an object consisting of a hollow shrinkable blank having in it an article about which the blank is to be shrunk, said machine having in combination a carrier adapted to have the object presented to it in such manner that an end of the carrier eX- tcnds into the mouth of the blank, means for clamping the mouth of the blank to the carrier with the end of the carrier which extends into the blank spaced from the adjacent end of the article, a shrinker, and means for producing relative movement of approach between the carrier and the shrinker to cause the hollow blank to be acted upon by the shrinker.

15. A machine for operating upon an object consisting of hollow shrinkable blank having in it an article about which the blank is to be shrunk, said machine having in combination a carrier having an end adapted to be inserted into the mouth of a hollow blank containing an article about which the blank is to be shrunk, means for clamping the mouth of the blank to the carrier at spaced localities with the end of the carrier which extends into said mouth spaced from the adjacent end of the article, and means for producing relative movement of approach between the carrier and the shrinker to cause the hollow blank to be acted upon by the shrinker.

16. A machine for covering an article, said machine having in combination a carrier adapted to be inserted in the mouth of a hollow blank which is capable of shrinking about an article contained in it, means for holding the mouth from movement with respect to the carrier,

means for shrinking the blank, and means for creating a partial vacuum in the blank and for creating slack in the wall of the blank between the adjacent ends of the carrier and the article.

17. A machine for covering an article, said machine having in combination a carrier for a hollow blank capable of shrinking and containing an article about which it is to be shrunk, means for clamping the mouth of the blank to the carrier, a member yieldingly mounted in the carrier and engaging article, a shrinker, and means for producing relative movement of approach between the shrinker and the carrier to cause the blank to be acted upon by the shrinker.

18. A machine for covering an article, said machine having in combination a carrier having an end adapted to be inserted in the mouth of a hollow blank which is capable when heated of shrinking about an article contained in it, means for clamping the mouth of the blank to the carrier in spaced localities, means for applying suction through the carrier to the interior of the blank, a heater, and means for producing relative movement of approach between the heater and the carrier to cause the hollow blank to be heated and shrunk, whereby, as soon as the mouth of the blank has shrunk about the end of the carrier, the suction is efiective to produce a partial vacuum in the blank.

ALEXIS E. USHAKOFF.

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