US1740766A - Control for jarring molding machines - Google Patents

Description

Dec. 24, 1929.

CONTROL D. J. CAMPBELL FOR JARRING MOLDING MACHINES Filed Dec. 10, 1924 4 Sheets-Sheet l A WA r z 35 -a9' 3.1 o

' 1 16 ,g Inuznror Dona\ J-GQmPbQ 1929. D. J. CAMPBELL ,7

CONTROL FOR JARRING MOLDING MACHINES Filed Dec. 10, 1924 4 Sheets-Sheet 4 Inveni'ov 'Doncfld J. Campbell Patented Dec. 24, 1929 DONALD J. CAMPBELL, OF MUSKEGON HEIGHTS, MICHIGAN CONTROL FOR JARRING MOLDING MACHINES Application filed December 10, 1924. Serial No. 754,930.

This'invention relates to a machine to be used in molding, and is particularly directed to mechanism automatically operated by compressed airand constructed for elevating and letting fall repeatedly a table or ram 0n which a flask with a pattern and sand therein may be located, so that the sand within the flask and around the pattern may be condensed to the proper density, the operation in eflect being a jarring of sand in a flask to the necessarily condensed form wherein it will be suitable for a mold. It is an object and purpose of the present invention to provide a construction which will serve to produce this jarring at close intervals after it is once started, and which after a predetermined number or cycles of operation automatically stops and remains inoperative until again started. Many novel details of con struction and combinations and arrangements of parts for effectively attaining the above described effects are provided in-the construction, one embodiment of which is shown in the accompanying drawings, in which, I

Fig. 1 is a vertical section through the molding machine made in accordance with my invention.

Fig. 2 is a horizontal section taken substantially on the plane of line 22 of Fig. 1.

Fig. 3 is a vertical section through the automatic valve mechanism forming a part of my invention, the valve being shown in upper position,

Fig. 4 is a view similar to Fig. 3, the valve being in lower position.

Fig. 5 is a horizontal section taken substantially on the plane of line 5'5 of Fig. 3.

Fig. 6 is a like view on the plane of line 66 of Fig. 3.

Fig. 7 is a fragmentary side elevation of the ratchet mechanism used to time the stopping of the jarring of the machine.

Fig. 8 is an elevation of one'type of ratchet disk which may be used with said mechanism.

Fig. 9 is a horizontal section substantially on the plane of line 9-9 of Fig. 3, and

Fig. 10 is a fragmentary side elevation of 50 the lower part of the machine where said .A piston 4 is located within the cylinder 3 automatic valve mechanism is attached, the valve mechanism being removed.

Like reference characters refer to like parts in the difl'erent figures of the drawings.

In the construction a heavy base 1 is pro- 5 vided from which a cylinder 2 extends vertically for a distance, the same at its upper end being enlarged and continued upwardly as a larger cylinder 3, as shown in Fig. 1.

O0 and equipped with ring packings,from which a smaller piston 5 extends downwardly inside of the cylinder 2, it also near its lower end being equipped with packing rings to hold the compressed air which is introduced under the lower end of the piston 5 as will later appear. A head 6 is connected to the upper end of the piston 4, in turn carrying a member 7 and a board 8 on which the pattern 9 is placed with a flask 10 around the same,

the sand 11 being disposed within the flask and around the pattern.

At one side of and near the lower end of the cylinder 2, a valve casing is located and firmly secured, including a lateral portion 12 integral with which is a vertical valve casing 13, the same being bored from its lowerend upwardly nearly at its end to make an elongated cylindrical opening 14 therein, the lower end of which is closed by a screw plug 14. A horizontal passage 15 is made through the lower part 12 joining at its end with a passage 16 made through the cylinder wall 2 at the extreme lower end of the cylinder, as shown in Figs. 1, 3 and 4. An outlet 17 is made through the valve casing 13 at the upper end of the opening 14, and a hose connection 18 is made with suitable fittings, one of which screws into the outlet opening 17 and the other of which may be screwed into any one of a series of horizontal openings 19 made at diflerent levels through the adjacent wall of the cylinder 2, all of the openings eircept the one with which the hose 18 is associated being securely closed by plugs 20.

In the opposite side of the valve casing 13, a relatively small horizontal passage 21 is provided a distancebelow the upper end of the cylindrical opening-.14, and at the upper end of said opening 14 and directly opposite the outlet 17, an additional tapered opening 22 is made forming in eflect a valve seat, associated with, which is a tapered pin 23 enlarged at its outer end and threaded so that it may be adjusted toward and away from the seat, provided at 22. The screw threaded portion of'the pin 23 is notched or slotted longitudinally, as indicated at 24, whereby passages are provided for the escape of air outwardly past the pin 23; and this escape may be regulated as to volume and amount by different adjustments of the pin 23 as is obvious. An inlet opening 25 is made through the valve casing 13 in substantial alignment with the passage 15 before described and at the opposite side of the casing. A pipe 26 for carrying compressed air is screwed at one end into the casing, joining with said opening or passage 25, and at its opposite end is connected with a second valve casing 27 having an inlet with which a pipe 28 is connected for carrying compressed air' from a main supply tank of air. A horizontal web 29 with openings therethrough is formed integral with and located within the valve casing, above which a movable valve member 30, alsohavingopenings therethrough is located, the same being pinned to a vertical shaft 31 which extends upwardly through the upper side of the valve casing 27 and through a suitable stufiing box for preventing the escape of the air, as shown. By turning the rod 31 manually to one position the openings in the web 29 and the valve member 30 are in conjunction and air can flow through the casing 27. But when turned to another position the openings making passages for the air are closed and the compressed air is kept from passing through the valve casing 27 as is evident.

Within the valve casing 13 a vertically movablfevalve 32 is located, having a rod 33 connected at its upper end, the same extending upwardly through the upper end of the casing 13. The valve 32 has a passage 33 made vertically from its lower end to the rod 33. A short distance above the lower end of valve 32 a relatively wide and deep annular groove 32 is cut around the valve and on the inner side of the valve, that is, the side toward the cylinder 2 of the machine, a vertical groove or, passageway 34 is formed, the same extending from a short distance below the upper end of the valve 32 to a short distance above the annular groove 32*. In

' one position of the valve, as shown in Fig. 4,

this passage 34 joins the inlet passage 15 with an opening 35 made through the side of the valve casing a short distance above said opening or passage 15; and in another opposite position, that shown in Fig. 3 where the valve 32 is elevated, said passage 34 is elevated sufliciently that the connection between the passages 15 and 35 is broken, while in such elevated position the groove 32 is-located in the same plane with the aligned passages 25v from twisting by its sliding engagement with a rigid vertical rod 39 which passes through a projecting free end of the bar 39. At its opposite end bar 39 is connected with a link 40 which, in turn, is connected with oneend of a lever 41 pivotally mounted between its ends on a stub shaft 42, carried by an arm 43 integrally cast with and extending upwardly from the valve casing 13. A ratchetwheel 44, having a plurality of ratchet teeth, is loosely mounted on the stub shaft 42 and at one or morepoints between certain of the ratchet teeth is formed with deep cut notches 45 which are deeper than the notches cut in forming the regular teeth on the wheel. An arm 46 is also loosely mounted on the stub shaft 42, both the ratchet-wheel and arm 46 being disposed between the support 43 and the lever 41. Lever 41 extends beyond the ratchet-wheel and is equipped with a pivotally mounted spring actuated pawl 48, the end of which engages with the ratchet-wheel as shown, while a dog 49 is pivotally mounted on the support 43 being spring actuated to engage with the ratchet-wheel at a point nearly diametrically opposite the point of engagement of the pawl 48 therewith. The dog 49 is for the purpose of holding the ratchet wheel against return rotation. Arm 46 at its upper end is extended a short distance outwardly and terminates in a nose 47 under which the pawl 48 may engage when it is:-

seated in a notch 45, but over which the pawl passes when engaged in any of the other notches between the teeth of the ratchetwheel. 9

A connecting rod 50 has pivotal connection at one end with the outer end of arm 46 andat its opposite end to an arm 51 fixedly secured to the rod 31 This is best shown in Fig. 2.

After the flask and pattern has been placed in position and the flask filled with sand the rod'31 is manually operated so as to move the valve member 30 into position such that the compressed air may flow free- 1y through the valve casing 27, the pipe 26 and passage 25 and thence through lateral opening 36 to the vertical passage 33 in valve member 32, the valve being in the position shown in Fig. 4. The compressed air under such circumstances passes downwardly through the passage 33 and the branches shown at the lower end thereof coming under the valve and causing it to be elevated to the position shown in Fig. 3. In this position the annular groove 32 around valve 32 joins passages 25 and 15 so that the air may pass in considerable volume to and underneath the piston 5. This causes an elevation of the pistons 5 and at and the flask, pattern and mold carried thereon until the piston passes above the outlet opening 19 which is joined with the hose connection 18, whereupon compressed air flows through said hose 18 and the opening 17 into the valve casing 13 above the upper end of the valve As a result the valve 32 is driven downwardly to lowerposition, that shown in Fig. it, and the air under the piston 5 has a free outward passage through the passages 16, 15, 3% and 35, exhausting to the outside atmosphere. In the meantime or as soon a the passage 19 is again completely-covered by a side of the piston 5 on its downward movement, the air again flows to the passage 33 to and in under the lower end of valve 32, causing it to again rise. The cycle of operations'is thus repeated and continues until it is automatically stopped by a construction for such purpose, the operation of which will be later described. It is evident that the air which is above the valve 32 on the upward movement of said valve escapes outwardly through the passage 22 and that which is below the lower end of the valve escapes outwardly through the passages 37,

38 and 21 when the valve is moved tolower position.

Vith each reciprocation of the valve 32 the bar 39 is raised and lowered with a consequent turning of the lever 41 back and forth on the stub shaft 42. Pawl 48 turns the ratchet-wheel one step on the downward movement of the valve and slips back over a tooth of the ratchet-wheel on each upward movement of the valve. This continues until the pawl reaches one of the deeper cut notches 45, whereupon with the next turning movement of the ratchet-wheel, the end of the pawl 48 engaging underneath the nose a? causes the arm 46 to swing about the axis of the stub shaft 42 witha consequent turning of arm 51' by reason of the connection made bv the connecting rod 50. When this occurs, the valve member at 30 is moved to close the passages for compressed air through the valve casing27, and the operation of the machine is automatically stopped until such time as the rod 31 is again turned manually. The effect of this manual turning of the rod 31 in opening the valve at 29 and 30 is to; at the same time, swing the arm 46 (see Fig. '1' in a clockwise direction, whereupon the no se a7, at the upper end of the arm. bearing again'stthe upper point of pawl 48, .forces the same downwardly and outwardly, the

for green sand molds.

pawl riding against the lower edge of the notch 45 in which it is seated, and lever 41 succeeding deeper cut notch 4.5 reaches the pawl t8. In practice the number of notches 15 in a ratchet-wheel 44: may be as many as desired. In Fig. 8, a ratchet-wheel is shown with three of these notches while in the remainder of the figures the ratchet-wheel is shown with but one of said deeper notches, it being evident that with the latter form of ratchet-wheel the cylinder carrying the flask, pattern and mold is operated up and down, before stopping, as manv times as there are notches in the ratchet-wheel; while with a ratchet-wheel like that shown in Fig. 8 it is operated only one-third as many times before stopping.

\Vith this construction the flask and mold may be raised and lowered repeatedly and thereby jarred until the sand has been condensed to the required and proper density so that with a subsequent squeezing operation performed following such vibration and jarring, the mold will be of proper character The operation is entirely automatic except for the one manual operation of starting the machine in motion, that is by turning the rod 31 to open the valve within the valve casing 27. The movement of the ram or cylinder is fairly rapid and a flask filled with sand may be tamped and condensed with considerable speed. .The

and is to be considered as comprehensive of all forms of structure coming within their scope.

I claim:

1. In a machine of the class described, a cylinder, a piston mounted for reciprocation therein, an automatic valve having a reciprocable member for the purpose of alternately admitting air into the cylinder below the piston and exhausting the air therefrom to cause reciprocation of the piston in the cylinder, an air supply pipe communicating with said automatic valve, and means actuated by said reciprocable member for stopping the passage of air to the cylinder after the reciprocable member has moved a predetermined number of times. Y

a 2. In a machine of the class described, a cylinder, a piston mounted for reciprocation therein, an automatic valve having a reciprocable member for the purpose of alternately admitting-air into the cylinder below the piston and exhausting the air therefrom to cause reciprocation of the piston in the cyl piston and exhausting the air therefrom to cause reciprocation of the piston in the cylinder, an air supply pipe communicating with said automatic valve, a valve in the air supply pipe adapted to be manually opened, a ratchet wheel having a deep recess at one point between two of its teeth, a lever oscillated by said recip rocable member, a pawl mounted on said lever to engage the ratchet wheel, a pivoted arm having an extension.

to be engaged by said pawl when the pawl is in the said deep recess of the ratchet wheel, and means connecting said arm with said valve whereby the valve is closed when the arm is moved by engagement of the pawl with the extension on the arm.

4. In mechanism of the character described, a vertical cylinder, a piston mounted for reciprocation therein, an air conduit for carrying compressed air to the lower end of the cylinder below the piston, a manually operable valve for opening said conduit for the passage of compressed air therethroug-h, air operated means movably mounted and extending across said air conduit, said air operated means being movable to two positions in one of which there is free passage of air to the cylinder and in the other of.

which such passage is closed and an exhaust passage for air outwardly from the cylinder opened, and means operated by said air operated means for operating the manually operable valve to closing positionafter a predetermined number of operations of said air operated means. r

5. In combination, a vertical cylinder, a piston mounted therein, means for conducting compressed air to the cylinder below the lower end of the piston, a valve in said air conducting means for manually controlling the passage of air, means located in said air conducting means between the valve and the cylinder for automatically controlling the passage and exhaust of air to and from the cylinder,.and means operated by said last named means and connected with said valve for automatically moving the same to closed position after a predetermined number of reciprocations of the piston in the cylinder made by said passage of air to and exhaust from the cylinder, substantially as described.

6. In a construction o'tthe class described, a vertical cylinder, a piston mounted for reciprocatory movements therein, an air conduit for carrying compressed air to the lower end of the piston, a reciprocating valve mounted across said air conduit, a manually operable valve located in saidair conduit beyond the reciprocating valve, means for carrying air to one end of the reciprocating valve to move it in one direction to a position in which air may pass freely to the cylinder and elevate the piston, means for carrying air from said cylinder to the opposite end of said reciprocating valve after the piston has been elevated a predetermined amount, thereby forcing the valve in the opposite direction wherein the passage of air to the cylinder is blocked and an exhaust for air from the cylinder is opened, the piston dropping by gravity, and means operated by the reciprocat-ions of said reciprocating valve connected with said manually operable valve for closing the manually operable valve after a predetermined number of reciprocations of the reciprocating valve, substantially as described.

7. In a machine of the class described, a table mounted for reciprocation, fluid operated means to reciprocate said table, aofluid supply pipe communicating with said recip rocating means, a valve in said fluld supply pipe adapted to be manually opened, a ratchet wheel having a deep recess between two of its teeth, a lever oscillated at each reciprocation.

of said table, a pawl mounted on said lever toengage the ratchet wheel, a member adaptedto be engaged by said pawl when the pawl is in the said deep recess of the ratchet wheel and means connecting said member with said valve whereby the valve is closed when the member is moved by engagement of the pawl.

In testimony whereof I ailix my signature.

DONALD J. CAMPBELL.

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