US1695305A - Ram - Google Patents

Description

Dec. 18, 1928.

C. B. UPTON RAM Filed Oct. 20, 1926 2 Sheets-Sheet l [NYE/V 70R. M 4 3 62% 1 ATTORNEYS. v

C. B. UPTON RAM Filed Oct. 20, 1926 2 Sheets-Sheet 2 E 7% w M 7 l7 TTOFUVEYJ Patented Dec. 18, 1928 UNITED STATES P AT snr Fries.

CHARLES B. UPTON, OF PIQUA, (EH10, AEisIGNUR TO THE FRENCH OIL MILL MACHIN- ERY 00., OF PIQ'UA, OI-IIO.

' RAM.

Application filed October 20, 1926. Serial No. 142,955.

This invention relates to rams, and particularly to rams for hydraulic presses, In such rams it is cust mary to provide a packing in the upper end of the cylinder to pre vent leakage of the pressure liquid which operates the piston of the ram. in the of single piece rams which were formerly used, it was necessary, in order to renew the packing, to remove the plates or other parts placed above the piston, and to lift the piston out of the cylinder in order to gain access to the packing for renewing it. This work required the attention of several men for several hours with the consequent loss from the shutting down of the press. To facilitate the renewal of the packing, rams have been made heretofore with the piston in two or more sections, so that part of the piston could be removed in order to expose the packing when the packing was to be renewed. In such rams the inner section was then moved inwardly to expose the packing above its outer end. Objections to the two-piece construction of the piston are that it is expensive, and that during the operation of the press the joint moves across the packing, and wears or cuts, and sometimes tearsout the packing, thus requiring more frequent renewals of the packing. An attempt was made to prevent injury to PELCK- ing by the movement of the joint of the two-piece piston across the same during the operation of the ram, by placing the packing groove quite a considerable distance inwardly from the open end of the oylinde but this was unsatisfactory because the groove was not conveniently accessible for the replacement or insertion of the packing.

. An object of this invention is to provide an improved ram with which the packing for the piston may be easily removed in a simple manner without dismantling or taking apart the piston; with which a more perfect packing effectmay be obtained; with which the packing may be renewed with a minimum of operations and in a minimum of time; and which will be relatively simple, effective, and inexpensive.

-Further objects and advantages will be apparent from the following description of an embodiment of the invention, and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

In the accompanying drawings,

Fig. 1 is a sectional elevation of a ram constructed 'in'accordance with the invention, and illustrating one embodiment thereof, the piston being shown in its normal inward posit-ion;

F 2 is a similar elevation, but showing the piston in the position which it oijcupies while the packingbetween the cylinder and the piston is being renewed; wFig. is sectional elevation similar to .l, bllb illustrating another embodiment oi the invention; and l ig'. t is a sectional elevation similar to 3, but showing the piston in its inward position while the packing is being renewed. s

In the embodiment of the invention illustrated in Figs. 1 and 2, a piston 10 is mounted for reciprocation in and closes the open end of a cylinder 11, and the wall of the cylinder is provided with an annular groove 12 closely adjacent toits open end for receiving a packing ring 18 or other packing device which acts against the outer peripheral surface of the piston in order to seal the joint between the piston andthe cylinder. This annular groove 12 is placed nearer the open end of the piston than has been customary heretofore, and the. piston 10. is made of a single piece which projects outwardly of the cylinder and beyond the picking ring while in its normal inward limit of movement as shown in Fig. 1. The piston may be somewhat cupshaped, if desired, as shown in Figs. 1 and 2, and provided. in its interior with a stiffening cross-bar 14. The inward movements of the piston may be limited by an adjustable limit rod 15, and the latter may be and preferably is carried by the piston. In this embodiment of the invention, the'rod 15 is threaded through the cross-bar 14, and also slidingly and rotatably mounted in a passage 16 in the inner end of the piston. The rod 15 extends entirely through the piston from end toend, and also is removable endwise therethrough. Its inner end is engageable with the inner or closed end of the cylinder as the piston moves in wardly, and thus it serves to limit the inward movement of the piston. Obviously by rotating the rod 15 it will be threaded through the piston to variable extents, and

thus one may selectively vary the point at which the inward movement oi the piston will be checked by reason the engagement of the inner end of the rod with the end. of the cylinder;

The passage 16 of the piston, through which the rod 15 passes, is provided at the inner endot the piston with a suitable packgland or device 17 through which the rod 15 passes and which eii'ectively the joint between the piston and the rod 15. it.

platen 18 may he detachably con ected to the outer end oi: the piston, as usual in hydraulic rams. The rod 15 may be locked in dis; feren't adjusted positions in any suitable manner such as by a lock nut 19 whiclris threaded upon the rod 15 and cupnable wi h the crossbar The upper end oi the rod 15 may be made square or otherwise noncircular, as at 20, so that it will receive a tool or wrench by which the rod 15- may be rotated.

Referring particularly to 1 the rear is shown as in the. POSltlOll occupied when i is in its normal inwardp This position is determined and be varied by threading the rod 15 through the piston to the desired extent, so that it will strike the inner end of the cylinder when the piston reaches its desired normal inward position.

In this posit-ion the outer end ot the )iston preferably extends just outwardly beyond the outer end' of the cylinder, and the rod 15 may he locked in this position hy tightening the nut 1'9 against the crossbar 14. The piston. reciprocates outwardly, and then returns to this Qosgion (hiring. its normal movements, and at no time during normal movements does the outer end of the one-piece piston cross the packing 13 in the cylinder wall;

When one desires to renew the packing 13, the platen 18 is elevated above the piston so as to expose the squared end 20 of the rod 15. The nut 19 is then loosened and the rod 15 rotated so as to retract it somewhat through the piston and allow further in ward movement of the piston into the pee?- tion shown in Fig. 2, where the outer end of the piston uncovers and exposes the groove .12 in which the pacliingli'l is disposed. he groove 12 being arranged very closely adjacent to the outerend of the cylinder is very readily accessible for renewal oi? the packing material. As soon as new packing has been placed in the groove, the rodil5 is again rotated to force it 't'tirther inwardly through the piston and againstthe inner end of ti e cylinder, and during t rotation the piston 10 will be forced outwardly into the position shown in Fig. 1, which will be the normal inward position of the piston.

Referring now to Figs. 3 and 4., the ram illust'ated is very similar to that shown in Figs. 1 and 2; except that the rod 15, corneeaeos responding to red '15, instead of being threaded through the cross-bar 1 41 in Figs. 1 and 2, is passed loosely therethrough and is threaded into the inner end of the piston 10 The end of the rod 11? which passes through the inner end oi the piston is surrounded by packing device 17 similar to that of Figs. 1 and 2 to prevent escape of the pressure fluid along the rod. The outer end of the rot 15 is ln'eferably reduced somewhat in diameter and at its outer end which passes through the cross-liar 1 h is threaded tor receiving one or lllOiQ 1 cl; nuts The inner end'oi the rod be yond the threads is also slightly reduced in diameter and it this section which moves nigh the packing so that threads h never enter or injure the packing material of the device 17. After the rod 15 has-been adjusted to the desired extent thro' h the piston, the lock nuts 21 may be tightened upon the rod 155 and against the cross liar i l so as to lock the rod 15 a ainst further and unintentionalrotation. the changing oi the ocking in the annuhir groove in the cylinder i accomplished in the same manner in Figs. 3 and at as in l and 2, and corresponding parts are do 'e'nated by corresponding reterence characters.

It will be observed that in both embodiinents ot the inV'SfltlOH which have been lustrated, the outer end of the one-piece piston will never the paeking and cut it during the normal use oi the piston. The manipulations nec ssary to renew the packing between the piston and cylinder are very few and simpl'e and may be performed in a minimum of tin'ie. The packing between the limit rod and the piston is also very etiective and simple and therefore no leakage occurs along or through the piston. The manufacture of the piston in a single piece,

reduces its cost, and. with such a bn'e-piece piston the time required to renew the packing is reduced very considerably because it is unnecessary to take the piston apart in order to reach the-packing.

It will be obvious that various changes in the details, which have been herein described and illustrated in order to explain the nature oi the invention, may be madeby those skilled in the art within the principle and scope of the invention as expressed in the append ed claims.

Claimszl. A rain comprising an open-ended cylinder, a piston recipr eating in and closing the open end of the cylinder, the cylinder having an internal peripheral groove closely adjacent its open end, packing means in said groove acting against the piston to seal the cylinder, a limit rod threaded through and carried by the piston and engageable with the inner end of the cylinder to limit the inward movement of the piston, the rod being adjustable to various extents through the piston by rotation, whereby the rod may be set to limit the normal piston movement inwardly before it uncovers and exposes said groove, and may also be adjusted to permit further inward movement of the piston sufficient to uncover and expose the groove when renewal of the packing means therein is desired, and a packing device acting be tween the rod and piston at a point located between the threaded connection ofthe rod and piston and the inner end of the piston beyond the range of the threads of the rod, whereby the packing device will be uninfiuenced by the threads of the rod as the rod moves through the piston sufiiciently to change the limit for the inward movement of the piston. T

2. A ram comprising an open-ended cylinder, a cup shaped piston reciprocating in and closing the open end of the cylinder, with the open end of the cup of the piston at the open end of said cylinder, said cylinder having an annular groove in the wall of the chamber in which said piston reciprocates at a point closely adjacent the open end of the cylinder, packing means in said groove acting against the piston to seal the joint between said piston and cylinder, a limit rod extending through the inner closed end of the piston and coacting with the inner end of the cylinder to limit the inward movement of said piston, said piston also having a support extending across the interior thereof adjacent its open end and supporting said rod while permitting its movement therein, said rod being adjustable endwise through said piston to vary the inner limit of movement of said piston from a normal position in which the outer end of said piston does not cross said packing means during its normal operation, to'a temporary position in which it crosses and exposes said groove and packing means to enable repairs to or replacement of said packing means, and means at the inner end of said piston for sealing the passage thereof through which said rod passes.

3. A ram comprising an open-ended cylinder, a one-piece piston reciprocating in and closing the open end of the cylinder, the cylinder having an internal peripheral groove closely adjacent its open end, packing means in said groove acting against the piston to seal the cylinder, a limit rod threaded endwise through and carried by the piston and engageable'with the inner end of the cylinder to limit the inward movement of the piston, the outer end of said rod being formed for the reception of a tool by which the rod may be turned in either direction, said rod having an abutment engageable with said piston to determine the maximum extent to which the rod is threaded through the piston inwardly of the cylinder, whereby when said abutment engages said piston, said rod will prevent inward movement of the piston sufliciently far to uncover said groove and expose said packing means, and when said rod is retracted outwardly said piston may move inwardly sufiiciently to uncover said groove and packing means for inspection, repairs or replacement of said packing means, and packing means carried by said piston around said rod between the threaded section of said rod and the inner end of said piston.

CHARLES B. UPTON.

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