US1790797A

US1790797A - of worcester

Info

Publication number: US1790797A
Authority: US
Publication date: 1931-02-03
Anticipated expiration: 1948-02-03

Description

Feb. 3, 1931. M. H. DAMERELL 1,790,797

OPERATING MECHNISM FOR HYDRAULIC PRESSES Filed Dec. 5, 1926 WVM? YM Patented Feb. 3.1931

UNITED STATES PATENT OFFICE HARK H. DAMERLL, OF WORCESTER, ASSACHUSETTS, ASSIGrN'OR TO WYMAN-GORCDON COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS OPERATIIN'G M'ECHANISM FOR HYDRAULIC PRESSES Application led December 3, 1926. Serial No. 152,491.

This invent-ion relates to mechanism for operating a hydraulic press and particularly for controlling the flow of high and low pressure water thereto. Such presses are 5 commonly `used for applying.) very heavy pressure to drop forgings to ring them to exact'final form and for many other similar purposes in which the full pressure of the machine is applied only at the final stage 10 of the operation and for a very short distance.

It has been customary, however, to actuate the press for its full stroke by the introduction of water under very high pressure, al- 15 though the extremel high pressure was commonly utilized only at the final stage of compression. Obviously water cannot be placed under very heavy pressure without the expenditure of power, which necessarily 2o involves corresponding expense. It is the object' of my invention to provide a hydraulic mechanism so desi ed that a very much reduced amount of igh pressure water will be necessary to actuate z5 the press, while the travel of the. press to and from final operative position is obtained largely by the use of cheap low pressure water.

`My invention further relates to arrange- I ments and combinations of parts which will be hereinafter set forth and more particularly pointed out in the appended claims.

diagrammatic representation of my invention is shown in the drawings in which Fig. 1 is a diagrammatic view, partly in section, illustrating a hydraulic press having my'improvements applied thereto;

Fig. 2 is a sectional elevation of my improved Venturi connection; and

Fig. 3 is a cross section thereof, taken along the line 3-3 in Fig. 2.

Referring to the drawings, I have indicated a hydraulic press 10 in which apiston 11 is adapted to move outward or upward, applying pressure to the work W and forcing it against a fixed anvil 12. The representation l of the press is illustrative only and is greatly reduced in size in relation to the remaining arts shown in Fig. 1.

5 ater is supplied to the cylinderl of I system through a pipe 3 0 and passes through the press through a pipe `1.4 having a three-way, hand-operated valve mounted therein. Low pressureV water from a feed pipe 16 is admitted to the cylinder 12 through passages17 and 18 (Figs. 2 and 3) in 'a Venturi valve connection 19, said low pressure water passing from the passages in the Venturi valve toa Venturi tube 20, and thereafter passing a check valve 21 and bein led to the press cylinder 13 through a fee pipe '22 and T-connection 23.

A check valve 24 (Figs. 2 and 3) is mounted between the passages 17 and 18 in the Venturi valve 19 and opens freely to permit entrance of low pressure water to the press cylinder 13. The check valve preventsl any flow of water in the opposite direction when the pressure in the system exceeds that of the low pressure water supply.

High pressure water is supplied t'o the a T-connection 31 to a nozzle 32 in the Venturi valve 19. The high pressure water is discharged from the nozzle 32 directly into the Venturi tube 20, from which it flows to the press cylinder 13 through the connections previously described. l While the parts thus far described substantially embody my present invention it. is frequently desirable to apply an even'higher pressure at the final stage of the ressing operation, and for this purpose Iphave 1ndicated an intensifier 40, comprising a piston 41 in a cylinder 42, said piston having a relatively large low pressure area and a relatively small high pressure area so that the pressure on the outlet connection 47 may be,

`for illustration, five times the pressure in the inlet connection 43.

The pipe 43 is connected through a threeway, manually-operated valve 44 to a feed pipe 45 and to an exhaust pipe 46. The feed pipe 45 is directly connected to the high pessure pipe 30 through the T-connection 3 Having described the details of construction of my improved mechanism, I will now dscribethe operation and advantages there- We will first assume that the piston 11 is at 1 00 its lowest position, with the cylinder 13 connected through the three-way valve 15 to the exhaust pipe 15 and with water at high pressure available in the ipes and 45. The check valve 24 will e closed under these conditions, preventing back flow of high pressure water to the pipe 16 and the three-way valve 44 will be manually set to close the pipe 45 and connect the pipe 43 to the exhaust pipe 46. The high pressure water from the pipe 30 will operate through the pipe 47 to depress the'piston 41 in the cylinder 42, forcing the water contained therein out through the exhaust pipe 46. l

The apparatus is then placed in operation`- by moving the valve 15 to shut off the exhaust pipe 15a and connect the pipe 22 to the cylinder 13. As soon as this is done, high pressure water will begin to ow through the nozzle 32 in the Venturi valve'19. The action of the water from the high pressure nozzle is being to lower the pressure in the clearly indicated in Fig. 2, the effect thereof assage 18 and cause the entrance of a large body of low pressure water through the pipe 16 and past to check valve 24. This low pressure water may come from any available water suppl such as the public water mains, and may e at any ordinary pressure such as twenty pounds per square inch. The area of the passages 17 and 18 and the low pressure pipes 16 is very much greater than the area of the openin through the nozzle 32, so that the flow o a 'small amount of high pressure water through the nozzle 32 induces a very large flow of low pessure water through the passages17 and The piston 11'is thus moved through its substantially unresisted range by the use of a small amount of expensive high pressure water and a large amount of inexpensive low pressure water; As soon as the piston encounters considerable resistance, the high pressure Water will build up the water pressure in the Venturi valve and in the other connections to a pressure above that of the low ressure water. When'this occurs, the chec valve 24 will close and the piston 11 will thereafter be operated directly by the high pressure water but for a very limited range of travel. l

In actual operation, the low pressure water may be at very low pressure or even at atmospheric pressure, while the high pressure water may be at five hundred pounds pressure, which pressure is attained at a cost many times greater than that of the low pressure water.

If a further and very heavy final pressure is desired, the hand operated valve 44 is moved to close the exhaust pipe 46 and connect the pipe 45 to the high pressure pipe 43. High pressure water then enters the cylinder 42, forcing the piston 41 upward and exerting a pressure perhaps ve times as great or twenty-live hundred pounds per square inch through the pipe 47 to the cylinder 13. As soon as the pressure rises, the check valve 21 closes, preventing back flow-of this very highy pressure water through the Venturi valve into the supply pipes 16 orl 30. The piston 11 is substantially at its final position before the intensified pressure is' applied, so that there is only a very slight actual flow of water through the pipe 47. l

To relieve thepressure, the valve 44 is rst actuated to connect the pipe 43 to the exhaust 46, whereupon the 'high pressure water from the pipe 30 will depress the piston 41 as previ- -tice it is found thata 4press may be thus operated with eighty per cent or more of low pressure water and twenty per cent or less of high pressure water. It will be particularly noted that this saving in high pressure water is effected without any attention by the operator who merely opens or closes the hand valve 15 in `the ordinary manner, and who need have no knowledge whatever of the operation of thel Venturi valve 19. v

While the flow of water past the check valve 24 may be caused to rsome extent by the low pressure in the pipe 16, it is caused very largel by the Venturi action of the tube 20 an the a paratus will operate satisfactorily when t e pipe 16 is connected to an open storage tank or reservoir in which the low pressure water is under no head whatever.

By the use of my improved connections, the cost of operationv of large hydraulic presses is reduced to a small fraction of the cost -under the usual operation, 'using high pressure water exclusively. vIt will be understood that the operation ofthe intensifier `is entirely optional and that the invention is equally valuable whetheror not an intensifier is used to give thenal extreme high pressure.

Having thus described my invention and the advantages thereof, Ido not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is 1. In a hydraulic' mechanismhaving an actuated member,'a low pressure water supply, a high pressure water supply, and means to give said member a substantially Vunresisted movement b the' use of a relatively small amount of 'gh pressure water and an amount of low pressure water man times greater than the amount of said hig pressure water, and to give said member its final movement by the use of hi h pressure water only, and for automatically regulatingthe supply of high and low pressure Water in accordance with the resistance, said means including a Venturi connection for said hi h and low pressure water supplies in said mei anism, causing a relatively large induced ow of low pressure water against slight resistance.

.2. In a hydraulic/mechanism having an actuated member, a lovvr pressure water sup`` ply, a high pressure water supply, and means to give said member a substantially unresisted f movement by the use of a -relatively small amount of high pressure Water and a rela.- tively large amount of low pressure water, and to give said member its final limited movement by the use of hi h pressure water only, and for automatically regulating the sup ly. of high or low pressure water in acl cor ance with the resistance, said means including a Venturi connection having a nozzle connected with the high pressure water sup-v provided with a relatively small out# aving a' draft tube connectedvvith,v

a relatively large inlet pipe for the low pressure water supply, and a check valve in said low pressure water supply having a ow ply and et and opening of several times greater area thanv the outlet ofsaid Venturi nozzle. v l In testimony whereof I have hereunto`v aiiixed my signature.

MARK

1 1. DMERELL.