US2619695A - Control for jarring mechanism in foundry machines - Google Patents

Description

CONTROL FOR JARRING MECHANISM IN FOUNDRY MACHINES L. C- YOUNG Dec. 2, 1952 3 Sheets-Sheet 1 Filed July 19, 1949 [III-5&0! l0 7 e 4 57 z INVENTOR. '0

L. C. YOUNG Dec. 2, 1952 CONTROL FOR JARRING MECHANISM IN FOUNDRY MACHINES Filed July 19, 1949 3 Sheets-Sheet 2 INVENTOR.

D- 1952 c. vduue ,619 5 CONTRQL. FOR JARRING MECHANISM IN FOUNDRY MACHINES Filed July 19, 1949 3 Sheets-Sheet 3 Patented Dec. 2, 1952 CONTROL FOR J ARRING MECHANISM IN FOUNDRY MACHINES Lester C. Young, Cleveland, Ohio, assignor to Spo, Inc., a corporation of Ohio Application July 19, 1949, Serial No. 105,553

3 Claims.

My invention relates to molding machines and more particularly to jolt molding machines adapted to aid in compacting the molding sand or other material.

In jolt molding machines, the jolt table is raised by a fluid pressure lifting means which comprises a piston element and a cylinder element adapted to be extended relative to each other and defining an extensible fluid pressure chamber. For the raising movement of the jolt table, fluid under pressure is introduced into the xtensible fluid pressure chamber to raise the jolt table relative to an anvil upon which the jolt table rests in its lowermost position. In operation, the jolt table is raised a predetermined distance above the anvil, and then the fluid is exhausted from the fluid lifting chamber, which permits the jolt table to fall by gravity and strike the anvil for producing a vjolting operation to aid in compacting the molding sand or other material in the molding flask or other container. In prior constructions, exhaust from the extensible chamber is eifected by providing an exhaust line which is normally covered by the piston. As the piston and cylinder move relative to one another, the exhaust line is opened and the fluid pressure is reduced. The jolt tabl then falls against the anvil. The prior devices are designed for a particular upward stroke under a selected load, and a determined severity of jolt impact under the selected load. These conditions cannot be varied after the machine is constructed, and consequently, if a lightweight mold is carried, it will be shaken to destruction.

An object of this invention is to provide a jolt machine which may be adjusted to accommodate various sizes of loads.

Another object of this invention is to provide a controllable air cushion for a jolt machine.

Another object of this invention is to provide an adjustable thrust for a jolt machine before releasing the power for a return stroke.

Other objects and a fuller understanding of my invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which:

Figure l is a transverse crosssectional view of a jolt molding machine base unit employing the features of this invention, the unit being in the lower rest position;

Figure 2 is the same sectional view as Figure 1, with the power chamber extended and the table raised into an elevated position;

Figure 3 is a transverse cross-sectional view of a modified form of a jolt machine base unit employing the features of. this invention, with the power chamber extended and the table in a raised position;

Figure 4 is a broken away sectional view taken at a angle with respect to Figure 3, illustrating the air intake .lines into the extensible chamber of th embodiment illustrated in Figure 3;

Figure 5 is the same sectional view as Figure 3, with the table in the lower rest position;

Figure 6 is the same view as Figure 4 in the lower rest position;

Figure '7 is a type of foundry equipment machine into which the base units of Figure 1 or 3 may b incorporated, the machine being of the roll-over type; and I Figure 8 is a stationary floor type of foundry machine into which either of the base units of Figure 1 or 3 may be built.

With reference to the Figure 1 of the drawing, my jolt machine comprises generaly a base II), a jolt table 24, a fluid pressure lifting mechanism comprising a piston I8 and a cylinder 29 interposed between the base It and the jolt table 24, and outer tubular shell II projecting upwardly from the base and terminating in an anvil I2 against which the jolt tabl strikes to aid in compacting the molding sand or other materials.

The base It may be of any suitable shape and has a relatively flat bottom adapted to rest upon a suitable foundation. The outer tubular shell II projects upwardly with respect to the base II] and. serves not only as an anvil against which the jolt table 24 may strike, but also as the protecting shield to prevent molding sand or other foreign abrasive substances from coming into the interior of the machine. The upper end of the anvil I2 is provided with a flat annular face I3 against which the jolt cable strikes.

In the basic unit illustrated in Figure 1 of the drawing, the cylinder 29 is the inner portion of a central core member I4. The core I 4 has an annular wall I5 defining a stationary piston mounted upon the base I 0, and the jolt table has a central flange which constitutes a cylinder I6 adapted to cooperate with the piston I5.

The core I4 is closed across the top by wall I1, and the wall I'I, coacting with the area of the table 24 within the cylinder wall I6, defines an extensible chamber I9 adapted to receive fluid under pressure. Thus, fluid may be entered into the chamber I9 through a convenient line 20 and the table 24 may be raised with respect to the core I4. Chamber I9 is employed in the illustrated embodiment of the invention as a squeeze chamber to push the table 24 steadily upward with a constant force. This action is employed trated in Figure 1, the cylinder 29 is a part of the core I4, and is stationary with respect to the base ID. The piston I8 is adapted to reciprocate vertically within the cylinder 29. A piston rod 22 extends through an opening 23 in the top wall I1, and is secured by any suitable means, such, for example, as by the nut 38, to the table 24. In the preferred embodiment, it is desirable to provide a large opening 23 and place a packing ,3I to prevent blow-by, and a guide bushing 54 therein in order that fluid pressure may be introduced between piston I8 and wall I! for return of the table 24 when the unit is used in the roll-overdraw type of machine illustrated in Figure '7.

The cylinder 29 is closed at the bottom by an exhaust plate 32. The exhaust plate 32 has an entrance port portion 4| in the form of a threaded plug, and an exhaust line 33. The plug port 4'I may be vertically adjusted with respect to the plate 32 and piston l8 because of the threadable engagement with plate 32, and may be locked in any selected position by a lock nut 55. The exhaust line 33 connects with an exhaust duct 34 through the base of the core I4. The exhaust duct 34 leads into a chamber 35 defined by the shell II around the core member l4. The exhaust plate 32 and the piston I8 define an extensible jolt chamber 38. Fluid under pressure is introduced into the extensible chamber 36 through means of a connecting series of conduits 31 suitably provided in the well-known manner. Fluid is exhausted from the extensible chamber 36 through the exhaust line 33 and exhaust duct 34 through the chamber 35 and out between the surfaces I3 and 28 on the shell II and table 24, respectively.

The plug port 4| in the embodiment illustrated in Figure 1 has a vertical cylindrical opening 42. Valve rod 38 is carried by the piston I8 and is located to enter into the cylindrical opening 42 when the table 24' and piston I8 are in the lower position illustrated in Figure 1. The valve rod 38 is dimensioned to closely fit into the cylindrical opening 42, and thereby efiectively block off the passage of air from the chamber 36 out through the exhaust line 33.

An intake port 39 is provided in the wall of the piston I8 and is positioned to form a continuation of the conduit system 3'! when the piston I 8 is in 'an exhaust port arrangement similar to the conduit system 31 which will be uncovered by upward movement ofthe piston l8, and therefore, after .4 a predetermined rise of the piston I8 the fluid under pressure would be exhausted from the power cylinder and the upward force relieved from the piston I8. Such a construction must be determined at the time the machine is constructed, and thereafter no alteration short of remodeling is possible to alter the length of the upward stroke under a predetermined load.

When fluid under pressure isconducted into the chamber 36, a relatively high moving pressure will be built up before the inertia of the table 24 and its load is overcome. Thereafter, even though the port 39 has moved to the closed position illustrated in Figure 2 of the drawings, the

.fiuid under pressure will continue to force the piston I8 upwardly for a considerable distance. This phenomena is well understood by those skilled in the art. The upward movement of the piston I8 may be arrested prior to the normal complete travel by opening of the exhaust line. As previously explained, opening of the exhaust line has heretofore been accompanied by uncovering of an exhaust port by upward movement of the power piston. In the illustrated device of this invention, the valve rod 38 extends into the cylindrical opening 42 a predetermined distance, and therefore will not withdraw from the opening 52 until after a predetermined rise of the piston I8. After the piston I8 has risen a distance sufficient to withdraw the rod 38 from the opening 42, the fluid under pressure will be exhausted from the chamber 36 through the exhaust line 33. Hence, this invention provides a means to control the length of the upward stroke in accordance with the weight of the table 24 and the load upon the table 24. Therefore, if the table 24 is to carry a light load, the plug II is adjusted to telescope with rod 38 only a short distance and thus open the exhaust relatively soon after the initial upward movement begins. For heavier loads the plug M is adjusted to extend the rod 38 far into the opening 42, and thus permit the fluid under pressure within the chamber 36 to continue acting upon the cylinder I8 for a longer period of time.

A further feature of this invention comprises the adjustment of the throat size from opening 42 into line 33. Heretoforethe exhaust line from the power chamber was fixed by the size of the opening provided at the time the machine was built. Thus, exhaust from the power chamber was heretofore allowed to escape at the same rate, regardless of whether the table 24 carried a heavy load or a light load. As a consequence, whenever a heavy load was carried by the table 24, the table 24 would force the piston I8 down very rapidly and the surfaces 28 and I3 would hit exceedingly hard and cause a violent jolt, often to the extent of destroying the bond of the molding sand being molded. This defect in the prior devices has been corrected in this invention by the provision of the adjustable throat. In the embodiment of the adjustable throat illustrated, a needle valve 44 is threadably extended through the bottom of the plug 4| toward the cylindrical opening 42. Openings 58 provide a passageway from opening 42 into line 33, and the needle 44 can be adjusted to cover any proportionate area at the openings 58. The needle 44 is held in a selected position by lock nut 51. Thus, the effective fluid carrying area of the cylindrical opening 42 may be controlled by adjustment of the needle valve 44. Therefore, the rate of exhaust may be controlled and provide a fluid cushion to retard the downward movement of the piston I8.

Further, when the rod 38 enters into the cylindrical opening 42, the exhaust action will be discontinued immediately and a considerable amount of fluid will be trapped in the chamber 35 and be compressed by the downward movement of the piston I8, thus building up a continually increasing resistance to downward movement of the piston I8 and provide a cushion to prevent extremely hard jolts.

In the Figures 3 and 5, an alternative embodiment of the improved jolt machine of this invention is illustrated, wherein the piston H8 is stationary, and the cylinder I29 is movable. with the.

table 24. In this embodiment, the valve rod I38 is adjustably carried by the table 24, and the exhaust line I33 is provided through the central axis of the piston rod I22. Entrance port MI is carried by the piston I I8, and therefore is stationary with respect to the movable valve rod I33. The valve rod I38 is longitudinally adjustable'by the provision of the threadable attachment to the table 24 as illustrated. The end of the rod I33 is provided with a socket opening 45 for convenient longitudinal adjustment. Entrance of fluid under pressure is substantially the same as described in connection with th embodiment of Figure 1, and is conducted into the chamber I36 through the conduit assembly I31 and intake port I39.

In both of the illustrated embodiments, the entrance ports M and MI are illustrated as being female types, and the valve rods as being male types. However, this condition may readily be altered if desired, and the rod 38 may be provided with an opening to extend down over the outside of a cylindrical entrance port portion.

A control assembly 40 of any suitable kind may be provided to deliver fluid under compression to the conduit assemblies 31 and I31.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. In a jolt mold making machine having a jolt table operated by a relatively movable piston member and cylinder member defining an extensible fluid pressure chamber, said chamber having a fluid entrance line and a fluid exhaust line, the provision of improved cushion valve means on said exhaust line comprising, a port member entrance to said exhaust line, said port member having a longitudinal entrance chamber therein, a longitudinal rod having a crosssectional configuration similar to the cross-sectional configuration of said entrance chamber of the port member, but smaller to the extent that the rod interfits into the entrance chamber, said port member bein carried by one of the relatively movable members, longitudinal adjustment mounting means mounting said longitudinal rod on the other relatively movable member, the relative movement of the rod and port member being along a common longitudinal path common to the longitudinal axis of the rod and entrance chamber, said port member being longitudinally adjustable along said path with respect to the member carrying said rod to provide a selected degree of telescoping of the rod into the entrance chamber.

2. In a jolt mold making machine having a jolt table operated by a relatively movable piston member and cylinder member defining an extensible fluid pressure chamber, said chamber having a fluid entrance line and a fluid exhaust line, the provision of improved cushion valve means on said exhaust line comprising, a port member entrance to said exhaust line, said port member having a longitudinal entrance chamber therein, a longitudinal rod having a crosssectional configuration similar to the cross-sectional configuration of said entrance chamber of the port member, but smaller to the extent that the rod interfits into the entrance chamber, said port member being carried by one of th relatively movable members, longitudinal adjustment mountin means mounting said longitudinal rod on the other relatively movable member, the relative movement of the rod and port member being along a common longitudinal path common to the longitudinal axis of the rod and entrance chamber, said port member being longitudinally adjustable along said path with respect to the member carrying said rod to provide a selected degree of telescoping of the rod into the entrance chamber, said exhaust line having a maximum fluid carrying capacity, line reducing valve means in said exhaust line, and valve operating control means extendin from said valve means to a position accessible externally of the jolt machine while that machine is in operation, whereby a given load may be placed upon the table and the exhaust outlet regulated while the jolt machine is in operation to give a precision degree of jolt.

3. In a jolt mold making machine having a jolt table operated by a relatively movable piston member and cylinder member defining an extensible fluid pressure chamber, said chamber having a fluid entrance line and a fluid exhaust line, the provision of improved cushion valve means on said exhaust line comprising, a port member entrance to said exhaust line, said port member having a longitudinal entrance chamber therein, a longitudinal rod having a crosssectional configuration similar to the cross-sectional configuration of said entrance chamber of the port member, but smaller to the extent that the rod interfits into the entrance chamber, said port member being carriedby one of the relatively movable members, means mounting said longitudinal rod on the other relatively movable member, the relative movement of the rod and port member being along a common longitudinal path common to the longitudinal axis of the rod and entrance chamber, and means to adjust said rod and said port member longitudinally along said path with respect to one another and thereby provide a selected degree of telescoping of the rod into the entrance chamber.

LESTER C. YOUNG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,157,403 Lewis Oct. 19, 1915 1,274,752 Norcross Aug. 6, 1918 1,547,056 MacNeill July 21, 1925 1,642,074 Lewis sept. 13, 1927 1,932,803 Radigan Oct. 31, 1933 2,438,218 Johnston Mar. 23, 1948 FOREIGN PATENTS Number Country Date 547,749 Germany Mar. 29, 1932

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