US2138410A - Molding machine - Google Patents

Description

NW2, 1938 F. T. SPIKERM-AN ET AL 2913394310 MOLDING MACHINE Filed July 6, 1935 2 Sheets-Sheet l ATTORNEYS Nov. 29, 1938. F. T. SPIKERMAN FLT AL.

MOLDING MACHINE Filed July 6, 1935 2 Sheets-Sheet 2 INVENTORS.

in f. OYSTER I "I a I) A ORNEY5.

Patented Nov. 29, 1938 UNITED STATES MOLDING MACHINE Frank T. Spikerman, Clinton, and Earl F. Oyster,

Shaker Heights, Ohio, assignors to S. P. O. Incorporated, Cleveland, Ohio, a corporation of Ohio Application July 6, 1935, Serial No. 30,102

4 Claims.

This invention relates to molding machines and more particularly to certain improvements therein whereby the stripping mechanism for removing the mold from the pattern will operate uniformly and effect an accurate draw regardless of any lack of alignment between the squeeze piston and its cylinder due to the normal working clearance or wear of the walls of the piston and cylinder.

In the conventional types of jolt-squeeze molding machines, the stripping mechanism is in fixed relation to the machine base and the squeeze cylinder, and an accurate pattern draw is entirely dependent upon the close fit between is the squeeze piston and the cylinder walls, and lack of alignment between the piston and the cylinder walls, due to wear or other causes, usually results in damage to the mold, during the drawing operation. 7

A further object of the invention is to provide a machine, embodying the improvements above mentioned, that will be comparatively simple in construction, reliable in operation, and competitive with existing machines as to cost.

Other objects of the invention and the features of novelty will be apparent from the following description taken in connection with the accompanying drawings, of which- Fig. 1 is a side elevation of a jolt-squeeze type 30 of molding machine, embodying our invention;

Fig. 2 is a composite view, partly in front elevation and partly in section on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged detail section of parts of 35 the stripping mechanism;

Fig. 4 is a detail section showing the means for preventing the squeeze piston from turning in the squeeze cylinder.

Referring to the drawings, It) indicates a ver- 40 tically arranged squeeze cylinder which, in the embodiment illustrated, is provided with a rearwardly extending frame H that is supported on the wheels I2, l3 and M to make the machine conveniently portable. If preferred, however,

45 the wheels l2, l3 and I4 may be omitted and the machine permanently secured to a suitable stationary foundation. Within the cylinder in there is a squeeze piston I5 which carries an inner cylinder I6 having a jolt piston ll therein,

50 this jolt piston being formed with the usual jolt table I8 at its upper end to receive the pattern plate IS.

The parts so far described are more or less conventional and the machine will be equipped 55 with the usual valves and conduits for supplying compressed air to the cylinders l and It and for controlling the operation of the pistons i and 11. Since our invention has no relation to these common features of the jolt-squeeze type of molding machine, we have omitted a description thereof.

The table [8 has a depending flange adapted to engage with the upper end of the piston l5 so that on the upward or squeezing stroke of the piston 15, the table I8, with the pattern plate and mold thereon, will be moved with the piston In the form of the machine illustrated, we have shown the vertically extending links 2i and 22, which are pivoted to the frame it at the points 23 and 24 respectively, and which carry the arm 25 on which the platen 26 is mounted, this platen being adapted to engage the mold and as a backing plate to oppose the squeezing pressure of the piston 15. The arm 25 is pivoted to the link 2| by the bolt 21 and the link 2! is provided with a series of openings 28 which are adapted to receive the bolt 21 so that the arm 25 may be positioned at difierent heights above the cylinder ID, to suit molds of varyng depth. In a similar manner, the arm 25 is connected with the link 22 by the bolt 29 and the link 22 is provided with a series of openings 30 corresponding with the openings 28 and serving the same purpose as the latter.

The links 2| and 22 and the arm 25 form no part of the present invention and the platen 26 may be supported by any other suitable or preferred means. In order to prevent the piston H from turning in the cylinder In, the piston is provided with a vertically extending rod at which is rigidly secured thereto in parallel relation with the piston axis, and this rod is slidable in a lug 32 that is cast on the side of the cylinder 10, as shown in detail in Fig. 4.

On opposite sides of the piston Hi there are radially extending arms 33 and 34 and each of these arms has secured therein, in any suitable manner, as by the taper fit 35 and nut 35, a downwardly extending guide rod 31 having a head or shoulder 38 at its lower end. Each of the guide rods 31 is in parallel relation with the axis of the piston l5 and has slidably arranged thereon a yoke 39. Each of these: yokes 39 carries at its outer ends the stripping pins Gil which, preferably, have screw threaded connections with the yoke so as to be vertically adjustable relative thereto. The upper ends of the pins 49 project through suitable openings in the table l8 and the pattern plate l9, so as to be engageable with a flask 4|, on the pattern plate. By this construction it will be evident that the yokes 39 and the stripping pins 40 are carried by the piston l5, and the yokes always move, on the guide rods 31, in parallel relation with the piston axis so that these parts are in no wise affected in their functioning by any tilting of the piston H5 in the cylinder ID, or any misalignment of the piston and cylinder axes due to clearance between the piston and cylinder walls or to wear of these walls.

Each of the yokes 39 is provided with aninwardly projecting lug 42 on its upper portion, and these lugs have inwardly and upwardly in" clined bevel surfaces 43 on' their undersides. Vertically extending arms 44 are pivotally mounted on the cylinder ID, as indicated at 45, and the upper ends of these arms are bifurcated to receive the rollers 46, the axes of which are substantially parallel with the surfaces 43; The

arms 44 are connected together by a treadle 4'! which extends around the front side of the cylinder l0 and is provided with the foot plate 43. One or more springs 49 cooperate with the treadle 41 to normally hold the upper ends of the arms 44 against the stop lugs 50 on the cylinder ID.

The operation of the machine will now be described. The normal inoperative arrangement of the parts is as shown in Fig. 2, and, it will be noted, the arms 44 are held in their forward position, to which they were previously moved by the operator depressing the treadle 41, by engagement with the lugs 42. Assuming thatthe flask 4| is in position on the plate l9 and filled with sand, and the machine otherwise ready for the squeezing operation, air is first admitted to the jolt cylinder It by means of the usual control valves (not shown) and the jolting action occurs. Upon the completion of the jolting operation the air to the jolting cylinder is cut off and air is then admitted to the cylinder it by a control valve not shown and the piston 15 moves upward until the plate 26 engages the sand in the flask and thereby stops the upward movement. When the formation of the mold has been completed, the air is exhausted from the cylinders and the piston I5 descends. When the lugs 42 pass the rollers 46 on the upward movement of the piston l5, thesprings 49 move the arms 44 over against the lugs 50 so that. on the downward movement of the piston IS, the rollers 46 will engage the surfaces 43 on the lugs 42 and thereby arrest the downward movement of the yokes 39. As :the piston I5 continues its downward movement, the stripping pins 49 move through the plate l9 and engage the flask 4|, which effects the stripping of the mold from the pattern on the plate I9. Due to the fact that the surfaces 43, on the lugs 42, are. inclined, as shown in the drawings, any tilting of the piston l5 in the cylinder I0, due to clearance or wear, will not materially affect the simultaneous engagement of the two surfaces 43 with the rollers 46. Since the stripping mechanism is all carried by the piston l5 and since the engagement of the surfaces 43 with the rollers 46 will occur simultaneously, it is obvious that the four stripping pins will engage the flask 4| simultaneously and therefore effect an accurate draw of the mold from the pattern. After the mold has been removed from themachine, the operator depresses the treadle 41 to release the yokes 39 from the holding arms 44 and the yokes will then descend until they engage with the heads 38 of the guide rods 31. Another flask may then be placed on the pattern plate I9, and the operations repeated.

As hereinabove stated, many of the features of the machine which we have illustrated and described are more or less conventional and are not a part of the present invention, but it will be evident that various changes may be made in the details of construction of the parts constituting the invention without departing from the spirit of the invention as defined in the appended claims.

Having thus described our invention, we claim:

1. In a molding machine, a frame provided with a cylinder, a squeeze piston in said cylinder and carrying a'pattern plate, guides carried by said piston on opposite sides thereof and externally of said cylinder, yokes slidable on said guides parallel with the axis of said piston, strippingpins on said yokes, each of said yokes being provided with a surface which is upwardly. and inwardly inclined with respect to the-axis of said piston and said surfaces being in symmetrical relation on opposite sides of said axis, movable means so arranged as to be engagedsubstantially simultaneously by said, surfaces on the, return stroke of said piston to positively stop said yokes and thereby effect the stripping movement of said pins relative to said plate, and means for simultaneously actuating saidmovable means to release said yokes therefrom.

2. In a molding machine, a frame provided with a cylinder, a squeeze piston in said cylinder and carrying a pattern plate, guides carried by said piston on opposite sides thereof and externally of said cylinder, yokes slidable on said guides parallel with the axis of said piston, stripping pins on said yokes, each of said yokes being provided with a surface which is upwardly. and inwardly inclined with respect to the axis of said piston and said surfaces being in symmetrical relation on opposite sides of said axis, arms pivotally mounted at opposite sides of said 0371- inderand provided with rollers at their upper ends for engaging said surfaces on the return stroke of said piston to positively stop said yokes and thereby effect the stripping movement of said pins relative to said plate, and means for actuating said. arms to releasesaid yokes.

3. In a molding machine, a frame provided.

with a cylinder, a squeeze piston-in said cylinder and carrying a pattern plate, guides carried by said piston on opposite sides thereof and exter nally of said cylinder, yokes slidable on said guides parallel with the axis of said piston, stripping pins on said yokes, each of said yokes being-provided with a surface which is upwardly and inwardly inclined with respect. to -the axis of said pistonand said surfaces being in symmetrical relation on opposite sides of said axis, arms pivotally mounted at opposite sides of said cylinder and provided with rollers at their upper ends for engaging said surfaces on the return stroke of said piston to positively stop said yokes and thereby effect the stripping movement of said pins relative to said plate, the axes of said rollers being substantially parallel with the respective surfaceswhich they engage, and means for actuating said arms torelease said yoke.

4. In a molding, machine, a frame provided with a cylinder, a squeeze piston in said cylinder and carrying a pattern plate, twopairs ofguide rods carried by said piston symmetrically arranged on opposite-sides thereof and externally of said cylinder, said rods being provided with shoulders at their lower ends, two yokes each of which is slidable on one of said. pairs of guide rods, stripping pins on said yokes, arms movably mounted on said frame adjacent said yokes, said yokes and said arms being provided with cooperating surfaces and rollers the surfaces and the axes of the rollers being upwardly and inwardly inclined with respect to the axis of said piston and being arranged so that each roller engages 10 its cooperating surface on the return stroke of said piston to positively stop said yokes and thereby efiect the stripping movement of said pins relative to said plate, said shoulders engaging said yokes on the squeezing stroke of said piston to move the yokes with the piston, and means for actuating said arms to disengage said surfaces and rollers and thereby release said yokes for movement to retract said pins with respect to said plate.

FRANK T. SPIKERMAN. EARL F. OYSTER.

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