US1517798A - Molding machine for foundry use - Google Patents

Description

Dec, 2, 1924.I 1,517,798

. J. B. NEESHAM l MOLDING MACHINE FOR FOUNDRY USE Filed April 13, 923 2 Sheets-Sheet l De', 2, 1924. 1,517,798 .J. B. NEESHAM Y HOLDING MACHINE FOR FOUNDRY USE Filed April 15, 1925 2 Sheets-Sheet 2 Patented Dec. 2, 1924.

tangas UNITED STATES PATENT OFFICE.

JOHN BIRCH NEESI-IAM, OF GLASGOW, SCOTLAND, .ASSIGNOR TO JOHN MACDONALD 3: SON LIMITED, OF GLASGOW, SCOTLAND.

MOLDING- MACHINE FOR FOUNDRY USE.

Application 'filed April 13, 1923. Serial No. 631,749.

To @ZZ whom t may concern:

Be it known that I, JOHN BIRCH NEE- sI-IAM, of 4 Kelvinside Gardens, Glasgow, Scotland, a subject of the King of Great 5 Britain, have invented a certain new and useful Improved Molding Machine for Foundry Use, ofvwhich the following is a specification.

This invention relates to foundry moldl0 ing machines.

In such machines having lifting rams operated by liquid pressure the upward movement of the lifting ram is generally too rapid and jerky to draw the pattern from the mould without damage, whereas it is desirable that the pattern Ishall be withdrawn from its mould without shock or jar.

To this end it has been proposed that the inlet orificeof the pressure fluid should be above the bottomv of the ram and that a small by-pass should be provided from the orifice to a point below the ram, in order that the ram should start and stop slowly. In another construction where the inlet orilice was below the ram it was proposed to attach to the bottom of the ram a iin to pass into the orifice 'and partially choke it during a very small portion of the stroke so that the ram should start and stop slowly.

:i0 I have found it undesirable that the lift should be in two stages, and prefer that the rate of lift should increase gradually from the start to near the end of the stroke. I have also found that there is no necessity for .5 a gradual check at the end of the exhaust stroke. Accordingly. I provide a foundry molding machine having a lifting ram operated by liquid under pressure, in which the liquid is so admitted into the cylinder 1&0 that the rate of upward travel of the lifting ram is caused to increase gradually from a minimum at or near the bottom of its stroke up to a maximum at or near the top of the stroke. The desired effect may be obtained by tapering the lower end of the lifting ram and providing in the side wall ofthe ram cylinder, adjacent to the top of the tapered portion when the ram is in lowermost position, a valve through which the operating liquid is forced into the cylinder, whereby, as the ram rises, the tapered portion gives a gradually increasing passage at the valve for the liow of the liquid and so allows a gradually increasing quantity of the liquid to enter the ram cylinder in unit time.

air admitted into the chamber.

A separate exhaust valve may be provided and arranged to open on the return stroke of the ram to exhaust the liquid rapidly from the ram cylinder and thereby expedite the speed of operation of the machine. The operating liquid may be contained in a chamber formed in the base of the machine and forced into the cylinder by compressed air or other pressure fluid, and the exhaust valve may be so arranged between the chamber and the bottom of the ram cylinder that when the pressure fluid is admitted to the chamber to raise the ram, the valve is closed but opens automatically, to return the liquid rapidly from the cylinder to the chamber, when the pressure in the chamber is relieved to lower the ram.

Oil is particularly suitable for use as the operating liquid.

These and other features of the invention will be disclosed as embodied in one constructional form of the invention which is illustrated, by Way of example, on the accompanying drawing, whereon Fig. l is a part sectional elevation of the molding machine embodying the features of the invention.

Fig. 2 is an enlarged sectional view of the lower part of the lifting ram cylinder and appertaining parts.

The molding machine comprises a base A, having an oil chamber B, and an outer cylinder `C which is secured to the base. A jarring ram Dis slidably arranged in the outer cylinder, between the inner wall of the latter and a hollow intermediate stepped or shouldered sleeve E, and a lifting ram F is slidably arranged within the sleeve which constitutes the mould lifting ram cylinder. The jarring ram is operated by pressure fluid admitted to the cylinder C below the same while the lifting` ram, as hereinafter more fully explained, is operated by means of the oil contained in the chamber B which oil is forced into the sleeve by compressed The upper part of the jarring rain D is bifurcated and forms two arms supporting the machine table G, while a cross head I-I attached to the lifting ram is arranged between said arms and supports lifting brackets J.

The bottom part of the intermediate shouldered sleeve E rests on a plate 1 accommodated in a recess at the upper part of the oil chamber Band provided with an aper- As previously stated, the speed of the lifting ra n1 gradually increases as the ram rises, thus ensuring that the mould is lifted from the pattern gradually, without shock or jar. The rate of upward movement of the lifting ram may be varied by adjusting the distance of the inner end of the oil inlet valve K from the adjacent outer wall of the lifting ram.

rlhe oil for operating the lifting ram is used over and over again and the supply in the chamber B only requires to be occasionally replenished.

Having now fully described my invention what T claim and desire to secure by Letters Patent is l. A foundry molding machine having in combination, a mould lifting ram arranged for operation by liquid under pressure and means on the ram for gradually increasing the `ate of upward travel of said ram to a maximum near the end of its stroke.

2. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for upward sliding movement by liquid under pressure admitted to said cylinder, and means on the ram so disposed rel'- atively to a liquid inlet in the cylinder wall that the rate of upward travel of said ram is gradually increased to a maximum near the end of its stroke.

3. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, means for gradually increasing the rate of upward travel of the ram to a maximum near the end of its stroke, and means in the cylinder wall for assisting in regulating the possible supply of the operating liquid to said cylinder.

il. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, means for gradually increasing the rate of upward travel of the ram to a maximum near the end of its stroke, and a valve adjustably arranged in the cylinder wall for assisting in regulating the possible supply of the operating liquid to said cylinder.

5. A foundry molding machine having in conibn ation. a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, a tapered portion on the ram and a liquid inlet to the cylinder so disposed relatively to said tapered portion that the flow of liquid is varied to gradually increase the rate of upward travel of the ram to a maximum near the end of its stroke.

6. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, a tapered portion on the ram and a liquid inlet to the cylinder so disposed relatively lo said tapered poi tion that the flow of liquid is varied to gradually increase the rate of upward travel of the ram to a maximum near the end of its stroke, and means for rapidly exhausting said liquid from the cylinder after the mould lifting operation is completed.

7. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, means to vary the fiow of liquid to gradually increase the rate of upward travel of the ram to a maximum at or near the end of its stroke, means for regulating the supply of operating liquid to the cylinder', and a valve in the cylinder for rapidly exhausting said liquid from the cylinder after the mould lifting operation is completed.

8. A foundry molding machine having a 1 cylinder, ay mould lifting ram arranged for operation within the cylinder by liquid under pressure, means to vary the flow of liquid to gradually increase the rate of upward travel of the ram to a maximum at or near the end of its stroke, and a liquid exhaust valve in the cylinder comprising in combination, a casing and a plunger arranged for movement within said casing in one direction by pressure fluid and in the other by resilient means.

9. A foundry molding machine having in combination, a hollow base, a cylinder supported by said base, a mould lifting ram arranged for operation within said cylinder by liquid under pressure, a-tapered portion on the ram and a liquid inlet in the wall of the cylinder adjacent to the top of said tapered portion when the ram is in lowermost position, whereby the rate of upward travel of the ram is gradually increased to a maximum near the end of its stroke, a valve for assisting in regulating the supply of the operating liquid to the cylinder and an cxhaust valve projecting into the hollow base and arranged for operation by pressure Huid admitted to the hollow base.

10. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, means to vary the flow of liquid for gradually increasing the rate of upward travel of the ram to a maximum near the end of its stroke, a supply valve in the cylinder wall, meansl for adjusting the position of the valve relatively to the side of the ram whereby the space between the valve and the said side is varied to regulate the possible supply of liquid to the chamber.

11. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, means to vary the flow of liquid for gradually increasing the rate of upwardtravel of said ram to a maximum at or near the end of its stroke, and an .exhaust valve comprisin a recessed plunger, a spring to move the punger in one direction, :a .casing surrounding the plunger' and having small orifices to admit the pressure fluid behind the plunger to move it against 'the spring and large orifices adapted when the pressure fluid is not acting to coincide with ysimilar orifices'leading through the 'plunger wall tothe recess therein for the exhaust liquid.

12. A foundry molding machine having in combinati-on, a cylinder, a mould lifting ram arranged forl operation Within the cylinder by liquid under pressure, a tapered portion on the ram and a liquid inlet in the wall of the cylinder adjacent to the top of the tapered portion When the ram is in lowermost position, whereby the rate of upward travel of the ram is gradually increased to a maXimum near the end of its stroke, and `an eX- haust valve comprising a recessed plunger, a spring to move the plunger in one'direction, a easing surrounding the plunger and having small orifices to admit the pressure fluid behind the plunger to move it against the spring land large orifices adapted when the pressure fluid is not acting to coincide with similar orifices leading through the plunger Wall to the recess therein for the exhaust liquid.

13. A foundry molding machine having in combination, a cylinder, a mould lifting ram arranged for operation within the cylinder by liquid under pressure, a tapered portion on the rain, a liquid inlet in the wall of the cylinder adjacent to the fop of the said ta` pered portion when the ram is in lowernlost position, whereby the rate of upward travel of the ram is gradually increased to a maximum near the end of its stroke, and an ex haust valve; the said inlet comprising a supply valve in the cylinder wall having means for adjusting the position of the valve relatively to the side of the ram whereby the space between the valve and the said side is varied to regulate the possible supply of liquid to the ram chamber, and the said exhaust valve comprising a recessed plunger, a spring to move the plunger in one direction, a casing surrounding the plunger and having small orifices to admit the pressure fluid behind the plunger to move it against the spring and large orifices adapted when the pressure fluid is not acting to coincide with similar orifices leading through the plunger wall to the recess therein for the exhaust liquid.

14. A foundry molding machine including a fluid pressure operated mould lifting ram, and means whereby the ram will directly control and cause a gradual increase of the flow of fluid thereto for causing the upward travelof the ram to gradually increase to a maximum near the end of its stroke.

In testimony whereof I aflix my signature in presence of two witnesses.

' JOHN BIRCH NEESHAM. Witnesses MARY GREEN, AGNES TILMovnn.

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