US2031345A

US2031345A - Tray making apparatus

Info

Publication number: US2031345A
Application number: US735362A
Authority: US
Inventors: Guy L Tinkham
Original assignee: McCord Radiator and Manufacturing Co
Current assignee: McCord Radiator and Manufacturing Co
Priority date: 1934-03-10
Filing date: 1934-07-16
Publication date: 1936-02-18
Anticipated expiration: 1953-02-18

Description

3936' I e. L. TI NKHAM 2,31,34

- TRAY MAKING APPARATUS Original Filed March 10, 1954 2 Sheets-Sheet l INVENTOR. Lia/L- fink/55172,

r fir A TTORNEY} G. L, TI NKHAM 2,031,345 TRAY MAKING APPARATUS Original Filed March 10, 1954 2 Sheets-Sheet '2 INVENTOR.

A TTORNEY! Patented Feb. 18, 1936 UNITED STATES TRAY MAKING APPARATUS Guy L. Tinkham, Detroit, Mich., assignor to McCord Radiator & Mfg. 00., Detroit, Mich., a

corporation of Maine Original application March 10, 1934, Serial No. 714,908. Divided and 'this' application July 16, 1934, Serial No. 735,362 Y 8 Claims.

Among the objects of my invention is to pro- I vide means for folding the blanks into tray form without undue stretching or elongation of the metal so as to retain the inherent flexibility of the metal to prolong the life of the completed trays.

In carrying out this object, I provide the blank folding apparatus with means operating during the forming of the tray to clamp only the portion of the blank constituting the bottom wall of the -tray whereby the remaining unclamped portions of the blank may be folded to form the side and end walls of the tray.

A further object of the invention is to provide the blank forming apparatus with recesses at the ends of the die to receive the folded extensions .25 which form at the ends of the side walls of the tray in folding the tray into'tray form from a one piece integral sheet metal blank. A further object of the invention is toso for the blank folding apparatus that the die and its cooperating plunger may be adjusted-as to length for the production of trays of different lengths.

I Other and further objects of my invention will appear from the following specification taken in connection with the accompanying drawings,

in which:

, Fig. 1 is a side view, with parts broken away and in section, respectively, of the blankfolding apparatus of my invention;

Fig. 2 is a top plan view of a similar character 10 of the. die of the apparatus; Fig. 3 is an enlarged transverse vertical sectional view taken through the blank folding apparatus on line 33 of Fig. 1;

Fig. 4 is an end elevational view of the die;

Fig. 5 is a perspective view of the sections comprising a side member of the die, sections being shown removed from the die and in separated relation to indicate how the length of the die may be varied;

Fig. 6 is a perspective view, partly in section, illustrating the manner in which an end portion of the blank is folded into the form shown in Fig. '7 by the folding apparatus of the preceding .455 Fig. 7 is a perspective sectional view showing 1 the end of the tray produced in shown in Fig. 6;

Fig. 7a is a similar view showing the fabric employed with the die to prevent scoring of the outer'surface of the tray walls; and

Fig. 8 is a plan view on a reduced scale of the fiat metal blank from which the tray is produced. The blank foldingv apparatus, as shown in the drawings, comprises a punch and die assembly. The die is. marked l and the punch is marked 2. These members are relatively-movable toward and from each other, the punch entering the die I to fold the tray from the fiat metal blank 3 which is interposed between them. The blank is placed between these members when the latter are in the separated relation as shown in Figs. 1 and 3. The blank has the shape shown in Fig. 8 and consists of a single integral piece of sheet metal of the gage and character required for ice tray purposes. The longitudinal or side edges of the blank along'the portions constituting the side Walls of the tray may be beaded or turned over to reenforce said side walls along their upper edges in the completed tray as shown in full lines in Fig. 8. The dotted lines on the blank in Fig, 8 indicate the lines on which the blank folds-in the production of the tray by the punch and the die. These lines will bereferred tolater.

'In the punch and die assembly shown; the punch 2 moves into and out of the die I, the latter being held stationary in the base of the machine. The die I comprises a pair of laterally spaced side members each composed of

end sections

4, 4 and an intermediate mid-section 5 as shown in Fig. 5. The side members are supported in the desired laterally spaced relation by

upright standards

6, 6 secured to the supporting base 7 of the machine as shown in Fig. 3. These standards are preferablyin the form of castings of similar height and length and are provided at their upper ends with inwardly facing L-shaped channels to receive the sections of the side members as shown. The channels provide the standards 6 with seating surfaces 8, 9 for the side members of the die. The sections are secured in the channels in any preferred manner, bolts It being employed for the 7 end sections 4 and screws I! for the mid-sections 5. The end sections 4 are adjustable longitudinally. This may be accomplished by having the heads l2 of the bolts It fitting in longitudinal slots or grooves [3 in the end sections as shown. This arrangement enables the length of the die to be changed to permit the making of ice trays of different lengths. In making this adjustment the manner the mid-sections 5 are replaced by longer or shorter ones as the case may require and the end sections are adjusted to accommodate the length of the associated mid-sections.

The grooves [3 for the bolts l0 and the apertures for the screws l I open through the outer side surfaces a of the

die sections

4 and 5 and not through their inner side surfaces b as shown. The surfaces b are retained smooth and continuous so that the side walls of the tray may be formed against them. The surfaces b as shown in Figs. 3 and 6 are inclined upwardly and outwardly from the lower edges of the sections to give the tray produced in the die the required draft for the discharge of the ice cubes from the tray.

The bottom wall for the die is provided by v member l4 reciprocally mounted in the base I of the machine between the side members of the die. Member Hi also serves to eject the formed tray from the die as the plunger2 leaves the same. The member I4 is supported by one or more rods I5 which extend downwardly from the member and enter pressure cylinders l6 where they are connected to pistons I! as shown in Fig. 1. The cylinders are connected to a compressed air supply which acts on the under sides of the pistons cushioning the lowering movement of the member M in response to the downward pressure of the plunger 2 thereon on folding the tray and raises the member on the up-stroke of the plunger to carry the formed tray out of and above the. die. The member I4 is guided in its up and down or vertical movement by sliding contact with the walls of a slot l8 formed by the opposed portions of the standards 6 at the base of the die and the end forming members I!) of the die to be presently .edges of the inner side surfaces 0 of the die are rounded as at (1 so that the metal blank as it is forced into the die may easily enter the tray forming cavity.

The end members I 9 of the die are located between'the standards 6 at the'ends of the side members of the die. These end members are secured to the end sections 4 of the die by screws 20 and have lateral extensions 2|, 2| engaging the standards in the channels provided for the side members of the die. The end members I9 also have depending web portions 22 fitting in the slot [8 between the standards as shown in. Fig. 1. The end members I9 are held against the side members of the die by set

screws

23, 23 mounted in

blocks

24, 24 fitting between the standards beyond the ends of the die. These blocks fit in the channels provided in the standards for the side members of the die and are rigidly secured to the standards by

screws

25, 25. The screws 23 impinge against their associated end members, and not only enable the end members to be adjusted when lengthening or shortening the die, but also clamp and hold the die forming members in tight engagement. The screws 23 have

clamp nuts

26, 26 thereon for locking the screws 23 in their adjusted positions.

To form the end walls of the tray the end members l9 have their body portions 21 extending into the die cavity at the opposite ends of the die. The portions 21 are laterally narrower than the width of the die cavity. This provides

vertical recesses

28, 28 in the die cavity at its ends on opposite sides of the portions 21 as shown in Fig. 2. These recesses extend the full depth of the die cavity and receive the metal of the blank forming the extensions e, e at the ends of the tray as shown in Fig. '7. The body portions 21 of the. end members l9 extend the full depth of the die cavity and have their inner surfaces g upwardly and outwardly inclined at substantially the same angle of the side members of the die to form the end walls 1 of the tray. The portions 21 also project slightly above the side members of the die to support the flat blank 3 above the same for its initial bending when forced into the die by the plunger 2 (see Fig. 1). The member I 4 also supports the blank in this position as shown in Fig. 3. Upward movement of the member l4 above this position is prevented by a stop 29 on the member l4 engaging a shoulder 30 on one or both of the standards as shown in Fig. 3. The stop 29 may be in the form of a cross head or web having a sliding fit in a recess 3| between the standards to aid in guiding the member I4 in its vertical movement.

The mechanism shown and described operates as follows: After the blank 3 has been placed in proper position between the punch and the die, the punch is connected with the power of the machine. The punch descends under this power and forces the blank into the die. The first action of the punch is to press the portion of the blank forming the bottom wall h (Fig. 8) of the tray against the member l4. As the downward movement of this member is resisted by the pressure in the cylinders IS, the blank is tightly clamped between the punch and the member l4. As these parts descend in unison under the downward pressure of the plunger, the blank is carried into the die cavity being bent along the edges of the bottom wall It to form the side walls 1', i and the end walls I, f of the tray. These walls follow the inner surfaces: of the die cavity and when the plunger reaches the bottom of the die, said walls stand in their desired upright relation to the bottom wall of the tray as shown in Fig. 7. The portions of the blank beyond the end walls I fold into the recesses 28 and provide the folded extensions 6 at the opposite ends of the tray. The end walls f are slightly higher than the side walls i and the extensions 2. This provides extensions in the form of flanges 7' on the upper edges of the end walls. These flanges remain co -planar with the end walls of the tray being exterior of the forming operation of the punch and the die. The flanges 7' are bent over the ends of the tray in. the completed device to secure the extensions e against the end walls of the tray and to secure a handle member (not shown) to one end of the tray. This handle member is preferably in the form of a metal bail over which the flange is turned to pivotally attach the bail to the tray. The subject matter of my invention pertaining to the handle member is embodied in my application, Serial No. 733,726 filed July 5, 1934 also a division of application Serial No. 714,908 aforesaid.

Clamping the blank 3 between the plunger 2 and its cooperating member 14 throughout the area of the blank constituting the bottom wall h of the tray and moving these members in unison into the die enables the tray to be formed by a avoided-and the inherent resiliency of the metal :folding rather than by a drawing action. Thus into the same by the plunger.

' under the blank 3 and prevents theside surfaces of the die contacting the blank as the latter is is retained, prolonging the life of the tray under frequent flexing when in use; The portions of l the blank constituting the side and the end walls for the gage of the metal of the blank, thetray is completely formed in one downward stroke of the plunger.

To prevent scoring or scratching of the tray, walls in the forming operation, Ipro-vi'de a protective fabric 33 shown in Fig. 7a. This fabric extends over the top of the die and is forced down The fabric lies forced into the die. The fabric is tensioned being fastened to rolls 34, 34 j ournaled on the machine on opposite sides of the die and extending the full length of the same. Cables 35 attached to the rolls connect with springs 36 which tension the fabric and return it to its normal position overlying the top of the die on withdrawal of the plunger therefrom.

On the up-stroke of the plunger 2 after the forming ofthe tray, the member 14 follows by the pressure on the pistons l1 and the formed tray is carried out of the die as indicated in dotted lines in Fig. 3. In this figure as well as in Fig. 1, the punch 2 is shown just after it has left the die. At the end of its upward move.- ment it is free of the raised tray so that the latter may be readily and easily removed from the machine. In Fig. 6 the member I4 is shown in its depressed or lowered position to clear the inner surfaces of the die for illustration. The formed tray is indicated by broken lines at T in Fig. 3.

The tray when ejected by the member l4 has 1 its end extensions e, e, extending outwardly be yond the ends of the tray as indicated-in Fig; 7.

It is to be understood that both ends of the tray are so formed. The tray is now placed in another machine or device and the extensions e, e are folded over the adjacent end walls I of the tray after which the flanges a are bent downwardly over the extensions e to clamp the extensions to the end walls and secure the latter in their upright positions. The handle member heretofore referred to is also attached to one end of the tray by the flange 7 at such end of the tray. This is accomplished by having the flange when bent over the extensions e also bent about the attaching portion of the handle member. This operation is performed on a device designed for the purpose.

The punch 2 is carried by the ram 42 of the machine. The punch is made sectional having end sections 43 and a mid-section 44. This construction enables the length of the punch to be varied to accommodate the punch to the length of the die being used. The sections are secured to the ram 42 in a channel 45 in the underside of the ram as shown in Fig. 3. The mid-section 44 of the punch is secured to the ram by one or more screws 46 while the end sections 43 are secured to the ram by bolts 41, the latter having square heads fitting in longitudinal grooves 48 in the end sections as shown in Figs. 1 and 3. This method of securing the punch sections to the ram is similar to the method employed for securing the side members of the die to the standards 6; The ram is moved into and out of the die through the power operated mechanism of the machine, which mechanism is controlled by a hand or foot operated releasing clutch as in punch press equipment.

' "After the tray has been formed, expansion joints are provided in the bottom and the side walls of the tray whereby the tray may be flexed in the hands of the user to fracture the mass frozen in the tray into the smaller sections or cubes, as defined by the joints, and free the frozen mass from the tray walls for immediate discharge from the tray. The mechanism for forming the 1 joints in the tray walls is disclosed and claimed in application, Serial No. 714,903 aforesaid. The

tray with its expansion joints is of the character covered by my Patent No. 1,894,897, granted on January 17, 1933 and co-pending applications, Serial No. 645,215 filed December 1, 1932 now Patent No. 1,997,832, granted April 16, 1935 and Serial No. 686,328 filed August 23, 1923 now Patent No. 1,997,839, granted April 16, 1935, the latter being a division, of the first mentioned application. The tray produced by the apparatus herein shown and described has awidth no greater than the width of the individual cubes or sections into which the mass frozen in the tray is fractured on flexing the tray. The tray is of course designed for use in mechanical refrigerators.

The details of construction and arrangements or parts shown and described may be variously changed and modified without departing from the spirit and. scope'of my invention except 9.5,.

pointed out in the appended claims.

I claim as my invention:

1. An apparatus for folding a substantially flat sheet metal blank into a tray, comprising a oooperating plunger and die, the latter having side and end walls, supports, one for the plunger and the other for the die, the plunger and the side walls of the die each being in sectional form, and means for securing the sections of the plunger and the die to their respective supports, the securing-means for certain of the sections of the plunger and the die constituting co-operating fastening means and longitudinal grooves therefor whereby said sections may be adjusted to vary the length of the plunger and the die to produce trays of different lengths.

2. In an apparatus for folding a substantially fiat sheet metal blank into a tray, a die having side and end walls, a support for the walls of the die, said support having a slot extending lengthwise of the die between its side walls and into which extend depending projections on the end walls for holding the latter in proper relation to the side walls, and means for. clamping the end walls against the side walls.

3. An apparatus for folding a substantially fiat sheet metal blank into the form of a tray having integrally conected side, end and bottom walls, comprising a co-operating plunger and die, means for clamping the portion of the blank constituting the bottom wall of the tray against the plunger whereby the remaining unclamped portions of the blank will fold along their conintegrally connected side, end and bottom walls, comprising a co-operating plunger and die, means for clamping the portion'of the blank constituting the bottom wall of the tray against the plunger whereby the remaining unclamped portions of the blank will fold along their connection with the clamped portion of the blank to form the side and the end walls of the tray as the blank is forced by the plunger into the die, a fabric sheet covering the under side of the blank and forced into the die with the blank to prevent scoring of the blank by the die, and means for automatically Withdrawing the fabricsheet from the die as the plunger leaves the same and holding the sheet in a normal position over the die.

5. The structure defined by claim 4 wherein the holding means comprises rotative elements on opposite sides of the die and to which the ends of the sheet are secured, and means for'normally rotating said elements in a direction to wind the fabric thereon.

6. An apparatus for folding a substantially fiat sheet metal blank into a tray having integrally connected side, end, and bottom walls, comprising a cooperating plunger and a die, the latter having stationary members providing the side and the end walls of the cavity provided by the die and a movably mounted bottom wall, and means providing a yieldable mounting for said bottom wall and normally urging the same toward the plunger, said plunger clamping the portion of the blank constituting the bottom wall of the tray against said movably mounted bottom wall on forcing the blank into the die whereby the remaining unclamped portions of the blank by contact with the stationary side and end walls of the die will be bent along their connection with the clamped portion of the blank to form the side and end walls of the tray as the plunger forces the blank into the die, said plunger and the movably mounted bottom wall of the die being substantially co-extensive with the portion of the blank forming the bottom wall of the tray to engage the bottom wall of thetray throughout substantially the entire area thereof.

7. An apparatus for folding a substantially flat sheet metal blank into a tray having integrally connectedside, end, and bottom walls, comprising a cooperating plunger and a die, the latter having a movably mounted bottom wall and stationary members forming the side and the end walls of the cavity provided by the die, said end walls extending across the space between the side walls and closing the cavity at the ends of the die, and means providing a yieldable mounting for the bottom wall of the die and normally urging the same toward the plunger, said plunger clamping the portion of the blank constituting the bottom wall of the tray against the movably mounted bottom wall on forcing the blank into the die to form the side and the end walls of the tray as the unclamped portions of the blank are forced against the stationary side and end walls of the die, the end Walls of the die having recesses to accommodate the folds in the metal at the ends of the tray to form extensions to be: bent over the end walls of the tray.

8. An apparatus for folding a substantially flat sheet metal blank into a tray having integrally connected side, end, and bottom walls, comprising a cooperating plunger and a die, the latter having stationary members forming the side and the end walls of the cavity provided by the die and a movably mounted bottom wall, and means providing a yieldable mounting for said bottom wall and normally urging the same toward the plunger, said plunger clamping the portion of the blank constituting the bottom wall of the tray against said movably mounted bottom wall as the plunger forces the blank into the die to form the side and end walls of the tray by contact of the unclamped portions of the blank against the stationary side and end walls of the die, the end walls of the die having projections extending into the die between the side walls in lateral spaced relation with respect thereto to provide recesses at the ends of the die toaccommodat-e the folds in the metal at thev ends of the tray on forming the tray in the die.

GUY L. TINKHAM.