US2085695A - Hydraulic press - Google Patents

Description

2 Sheets-Sheet 1 R. W. DINZL HYDRAULIC PRESS INVENTOR P. W D/NZL .Filed Dec. 23. 1953 7 & .ZL

June 29, 1 937.

June 29, 1937. R. w. DlNZL HYDRAULIC PRESS Fi1ed Dec. 25, 19:55

2 Sheets-Sheet 2 .i i 42 Vi il/197194! INVENTOR eMm/A ZL Patented June 29, I937 HYDRAULIC PRESS Richard W. Dinzl, Narbert h, Pa., assignor to Baldwin-Southwark Corporation, a corporation 'of Delaware Application December 23, 1933, Serial No. 703,863

2 Claims.

leakage from the hydraulic mechanism into the dry ice chamber. Various arrangements have heretofore been proposed involving packing glands and the like but have not met with the necessary degree of success either on account of the cost of manufacture or the inemciency of the 15 arrangements.

It is one object of my invention to provide an improved arrangement whereby .there is no possibility of the hydraulic actuating'fluid contaminating the dry ice or other material that may be contained within the material chamber. Y A more specific object is to provide a material chamber in combination with what is herein termed a cylinderram having a closed end for engaging the material. A further object in this respect is to provide preferably a material receiving cylinder in which is disposed a reciprocable hollow cylindrical ram having its innerend closed while a stationary piston is disposed within the hollow ram. As a result of this improved arrangement, the hydraulic fluid is contained wholly within the closed end of the ram without the use of any sliding joint for sealing the interior of the ram from the material chamber, thereby completely eliminating the possibility of leakage into the material chamber.

Another object is to provide an improved ar-. rangement as above described wherein the ramcylinder is adapted to bev moved in opposite directions by hydraulic pressure, or, to be moved 40 during the pressing operation by hydraulic pressure but returned by admission of liquid or gaseous material in the material chamber.

Another object is to provide an improved press of the above type in combination with a structural arrangement of the press and a lower movable platen for sealing and closing the lower end of .the material chamber.

Other objects and advantages will be more apparent to those skilled in the art from the following description of the accompanying drawings in which:

- Fig. 1 is a vertical sectional view through a press embodying my improvements; Fig. 2 is a side elevation of the press of Fig. 1;

Fig. 3 is a modified form .of press employing a cylinder ram adapted to be moved in opposite directions by hydraulic pressure.

In the particular embodiments of the invention which are disclosed herein merely for the purpose of illustrating certain specific forms among'possible others that the invention might take, I have shown in Fig. 1 a press having a base carrying a pair of joining columns 2 for supporting a crosshead 3. A lower platen 4 is moved vertically by a ram 5 supported in base I. Fluid pressure to this ram may be supplied from any suitable and usual means such as a pump. Supported upon joining columns 2 is a cylinder 6 having preferably a cylindrical material chamber! whose lower end is open. The upperend of this cylinder is provided with what might be termed an atmospheric packing gland 8. Reciprocably disposed in cylinder 6 is a cylinder-ram 9 whose lower closed end may be provided with a removable facing plate Hi. "This plate does not necessarily have a leakproof fit with cylinder 6 as it does not have 'to resist hydraulic actuating fluid. The upper end of ram cylinder 9 has a shoulder I l adapted to engage, the upper collar l2 of the packing gland when the ram cylinder is in its lowermost position to be described later. The ram cylinder has an internal cylindrical bore I3 to receive a stationary piston or ram element M. This piston is supported by crosshead 3 and actuating fluid pressure is supplied from any suitable source through a suitable valve controlled pipe I5 to the hollow interior of piston I4 or a suitable passage therein, whereby the fluid pressure may act upon the closed end of ram cylinder 9 to move the same downwardly. A packing gland i6 is interposed between piston i4 and ram cylinder 9. However, any hydraulic fluid that leaks past gland It will i not have direct access to the material chamber 1, and hence there is no possibility of contaminating the material therein.

In operation of this form of press it is assumed that ram cylinder 9 is in its uppermost position as shown, whereupon fluid pressure is admitted to ram 5 to move platen 4 into sealing and closing contact with the lower end of cylinder 6. To insure a tight fit, the contacting surfaces of platen 4 and cylinder 6 may be ground or provided with a suitable seal. However, with the lower end of cylinder 6 closed, material such as liquid carbon dioxide or a combination thereof with carbon dioxide gas is admitted through an inlet port I'I until by a liquid gauge or pressure gauge it is determined that the'proper amount of mate! rial has been admitted to chamber 1. Passage I1 is then closed and in accordance with standard dry ice practice, a suction pump is attached to another passage I8 to reduce the pressure in chamber 1, whereupon the liquid carbon dioxide turns to the well-known form of snow. Thereupon hydraulic pressure is admitted thorugh pipe I! to the interior of ram cylinder 9 to force the same downwardly and compress the material.

therein. During this pressing operation which requires a very high pressure, itis seen that the actuating fluid cannot pass through any packing gland directly to the material chamber 1, and hence. no contamination of the material can occur. When the block of material has been fully compressed or formed, the pressure on ram is released by any suitable valve mechanism, whereupon ram-cylinder 9 moves downwardly to eject the cake of material from the lower end of cylinder 6, during which time the platen 4 moves downwardly. 'When the cake is fully ejected, shoulder l I will have come into engagement with element I! to thus limit the downward position of the ram-cylinder.

Inasmuch as no return piston area is provided for the ram cylinder 8, it is moved upwardly by first moving platen l and ram 5 upwardly to close the lower end of chamber 1, whereupon liquid carbon dioxide and its gas are admitted through inlet H to chamber 1. The fit of cylinder ram 9 and plate III with cylinder 6 has suflicient clearance that the liquid or gaseous carbon dioxide under pressure may flow downwardly past ram cylinder 9 to the under side of plate In and thereby force the same upwardly to the position shown in Fig. 1, whereupon the compressing cycle is repeated.

In the modification of Fig. 3 the same general arrangement of press structure is employed as shown in Fig. 1, and hence similar parts are given the same reference numbers. However, to provide for the hydraulic return of a ram cylinder 9', the piston M has a reduced portion as shown to provide an annular chamber 20. Hence it is seen that fluid pressuremay be admitted below plate 22 to force ram cylinder 9' downwardly whereas fluid pressure may be admitted through pipe II to annular chamber 20 to move ram cylinder 9' upwardly. Packing gland I6 is completely free from direct communication with material chamber 1 so that any leakage of hydraulic fluid from annular chamber 20 cannot contaminate the material. Piston plate l0? does not require a tight leakproof fit with its surrounding wall because. any leakage past the piston into annular chamber Ill will merely flow outwardly through pipe 2| which would be open to discharge during the pressing operation.

The mode of operation of this arrangement is the same as in the other form except that the gas pressure of the material in chamber 1 is not used to move cylinder ram 9' upwardly but instead it is moved upwardly by hydraulic pressure which is suitably controlled by any usual three-wayvalve mechanism.

From theioregoing disclosure it is seen that in either form I have provided an extremely simple and yet highly efiective means whereby maximum pressure may be applied to the material without danger of contaminating the same while at the same time there is obtained other structural and functional advantages which'will be more apparent to those skilled in the art, these various features and any' other changes in structure or arrangement of parts being within thesplrit of the appended claims.

I claim:

1. A press comprising, in combination, means forming a material chamber, a cylinder-ram mounted for reciprocation within said chamber and projecting therefrom at one end of the chamber, said ram. having a portion permanently disposed within said chamber, means forming a substantially close fit between said chamber and cylinder-ram at said end, said cylinder-ram having a closed pressure and and the other end being open, and a piston disposed in said cylinder-ram and projecting through said open end whereby actuating fluid pressure supplied between said piston and said closed end is adapted to effect movement of the ram without leakage of actuating fluid into said material chamber.

2. A dry ice press comprising, in combination, a cylindrical material chamber having one end open, a ram actuated platen adapted to close and seal said open end, a hollow ram reciprocable in said material cylinder through the other end thereof, one end of said hollow ram being closed to provide a material engaging surface, a piston disposed within said hollow ram, said ram and material cylinder having clearance to permit flow of liquid or gas therebetween, and means providing an inlet to said material cylinder at a point where said hollow ram will overrun the inlet port, whereby liquid or gas pressure admitted into said inlet will flow through said clearance to said chamber and move said ram to a reloading position.

RICHARD -W. DINZL.

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