US2509991A

US2509991A - Fluid-pressure-operated vise using hydraulic lock and screw-actuated ram for clamping and having a fluid by-pass for quick separation of jaws

Info

Publication number: US2509991A
Application number: US683345A
Authority: US
Inventors: Kurtiss P Schenke
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-07-13
Filing date: 1946-07-13
Publication date: 1950-05-30
Anticipated expiration: 1967-05-30

Description

MW 39 W5@ K. P. SCHENKE ggm FLUIDPRESSURE0PERAIED vIsE: USING HYDRAULIC LOCK AND scREw-AcTUATED RAN FDR CLANPING AND NAVI G A FLUID BY-PAss FDR QUICK SEPARATION oF J Filed July 15, 194e Patented May 30, 195i) UNITED STATES FLUID-RESSURE-GPERALTED VISE USING HYDRAULIC LCK ANB SCREW-ACTU- AIEI) RAM FOR CLAMPING AND HAVING A FLUID BIZ-PASS FOR QUICK SEPARATION F JAWS Kurtiss P. Schenke, New York, N. Y.

Application July 13, 1946, Serial No. 683,345

(Cl. 8l--17.2)

9 Claims.

The presentinvention relates to improvements in vises and work `holding devices and more particularly to an improved fluid or hydraulic vise of a quick-acting type.

It is a major object of this invention to provide an improved vise or other work holder which utilizes hydraulic or other uid power to greatly` increase the magnitude of the manual forces which are applied. A further object resides in the provision of a manual actuating screw of relatively short movement cooperatively associated with a hydraulic ram and a hydraulic lock by means of which the vise can selectively be tightened or released and when released is free to be pulled open without the necessity of further rotation of the screw.

A further object lies in such an arrangement in a hydraulic vise wherein a relatively few turns of the manual screw converts the vise from` its freely movable condition through which it can easily be adjusted for varied sizes of work to the condition in which it grips the work with a high hydraulic or mechanical advantage. A still further object lies in an arrangement in which the transition from mechanical movement of the screw to hydraulic movement for gripping the work is entirely automatic and relieves the operator of the necessity of performing an additional step as required in most prior devices. It is a further object to provide a screw actuated hydraulic vise in which the screw is utilized to selectively condition the vise and to actuate the hydraulic means but wherein the screw is automatically relieved of the high stresses reacting through the vise structure when the work is gripped by the hydraulic pressure.

It is accordingly a `corollary object to provide such a vise of high gripping power in which the screw mechanism is subjected to relatively light forces and consequently very little wear. A further object resides Ain providing a vise capable-of such high pressures and capacity that it is usable as a hydraulic press for stamping. punching and other operations. Other objects of the invention include the provision of an improved vise which is time-saving and quick-acting in use and which incorporates a novel arrangement of its simple and trouble-free parts. Other objects and advantages will become apparent to those skilled in` the art after reading the present description and the accompanying drawings forming a part hereof, in which:

Fig. l is a side elevational View of a vise embodying the present invention;

Fig. 2 is asectional View to a larger scale of the screw and hydraulic mechanism of the vise of Fig. l in its work-gripping condition; and

Fig. 3 is a similar View of the same mechanism in its .disengaged condition.

.Referring now to Fig. 1 the numeral li` designates the stationary portion of a vise having a iiged stock or jaw t. The movable portion is designated by the numeral 'l and has a corresponding movable stock or jaw 8. A tongue or bar member ll is rigidly attached-tol movable portion 1 and extends through a suitable aperture within the fixed portion 5 in a manner well known in the art. A iianged base portion lll is formed at the bottom of the Xed portion and by which it may be attached to a bench i l as by the bolts l2. It will be understood that the novel features of my invention which are about to be described are equally applicable to vises of all types whether swivelling or universal, of the drill press type, or for work clamps, holders, or jigs and fixtures.

A tubular member I3 is preferably threadedly attached to the movable portion l as at 3d at its outer end and is similarly threaded at its inner end at 3,5 to a large piston it reciprocable within a chamber or cylinder l 5 formed within the xed portion t", dividing the cylinder into the portions l5@ and 15b. The piston is provided with a suitable seal or packing at Hip at its periphery to prevent leakage of iluid from one end of the cylinder to the other and a suitable seal is also provided at 5p to prevent iluid leakage th:ough the end of the cylinder around the tube i3. The far end of the cylinder is closed by a cylinder head H5 suitably attached by a plurality oi studs or screws Il. The end plate or cylinder head I6 is suitably apertured and threaded to :receive a filler pipe and cap assembly at i3 to provide both a reserve chamber for fluid and a column of air above the fluid for purposes to be hereinafter explained. A screw rod E9 threadedly engages the aperture 'la in the movable portion l and is coaxially disposed with respect to the bore in the tubular member I3. Fixed to the end of the screw rod iQis a ball hub 29 from which a handle 2| is supported for manually rotating the screw. The work is indicated by the construction lines 22 and the vise is adjustable to receive a wider work piece such as 22a `at which time the hub of the handle will be approximately at the position 26a.

'Referring now to Fig. 2 it will be noted that the screw rod iS continues co-axially within the tube I3 as a straight piston rod 23 on which a small piston or ram 2li is xedly mounted by the threaded lock nut 25 tightened against the shoulder 26. The rampiston 2li is reciprocable within the tube I3 for a limited distance and hydraulic iiuid is prevented from passing the periphery of the ram by the seal 24p. The piston rod has an extended reduced diameter portion 2l on which is slidably mounted `a piston valve 28 having a peripheral channel and a plurality of communicating radial passages 3S. An enlarged ported end or detent 29 is attached to the inner end of the piston rod 2l and is capable of extending through the central opening in the piston i4 and through the end of the tube I3. The piston valve 28 is spring-pressed by the compression spring 3B restrained by the detent 3l which is fixed to the rod 21. The travel of the piston valve 28 is limited axially by the

annular ring detents

32 and 33 Xed to the inner wall of the tube I3 which wall is provided with apertures or

ports

36 and 37. The piston I4 divides the cylinder I into a reservoir portion I 5a, and a working portion |5b and all hydraulic forces acting upon the piston I4 are transmitted directly to the movable vise portion l to which it is directly attached by the small bore cylinder tube I3.

In preparing the vise for use it will be filled with a suitable oil or other hydraulic fluid such that both chambers I5a and lib are filled with fluid up to the level indicated on the filler pipe I8 in Fig. l. The connection 5a may be utilized to bleed @if trapped air in the filling operation and both cylinders should be filled with fluid and free from air. The connection 5a may also be used for an indicating pressure gage and will show the clamping pressures being developed between the vise jaws 5 and Ii3. The screw threads I9 are righthanded and the handle 2l is rotated clockwise looking toward the Working end of the vise with the jaws in light contact against the work 22.

In the position of the elements shown in Fig. 2 it will be seen that the screw I9 has been rotated clockwise to a point where the piston end 29 has been extended beyond the piston Valve 28 Which, under the influence of the spring 3i! has been urged against the detent 33. In this position oi the piston valve 28 and the piston end 29 the ports 38 in the piston valve are cut ofi from the passages in 29 and the port 36. There is accordingly no fluid communication from one side of the piston I4 to the other, or between chambers Iba and I5b and a hydraulic lock may be said to have been created. Continued clockwise rotation of the screw I9 will assist the spring 39 in holding the piston valve closed and will build up fluid pressure within the tube I3 ahead of the ram piston 24 which pressure passes through the always open port 3'! into the working chamber I 5b against the face of the piston Iii. A power increase or boost is accordingly obtained which is approximately in proportion to the exposed areas of the pistons I4 and 24. The greatly increased force, and reduced axial motion, applied to the piston I4 is transmitted in the form of a tensile force through the cylinder tube I3 which in turn pulls the movable jaw 8 against the work 22. The clamping force applied to the work will accordingly be of great magnitude, many times greater than the manual force applied in turning the handle 2i, and the screw I9 will accordingly be relieved from transmitting the high clamping force, which is transmitted by the tube I3. Due to the relative incompressibility of the fluid in the cylinder I5 the piston M- will be moved a relatively short distance and as a result of this short movement the residual fluid in the chamber portion Ia will be compressed against the air above the fluid level in the lling pipe I8, which air serves as a pneumatic cushion and permits the iilling pipe to serve as an expansion chamber.

In order to release the clamping pressure and free the movable portion 1 to accommodate a larger work piece 22a., the screw I9 is backed 01T several turns to the position shown in Fig. 3. In this position it will be noted that the ram 24 has receded, permitting the pressure within the cylinder tube rI3 and the chamber I5b to drop and permit the rod end 29, assisted by the pressure within the chamber I5a to return the piston valve 28 to its open position against the detent 32. In this position it will be seen that the chambers I5a and |51) are in open communication through the

ports

3E, 38 and 29 and the hydraulic lock may be said to be broken or opened. It is accordingly not necessary to rotate the screw further inasmuch as a light outward pull on the handle 2| will permit the piston I4 and the attached movable portion 'I to be moved to the desired position, displacing iiuid from chamber I'b to chamber I5a. The larger work piece can be clamped in the extended position by again rotating the screw I9 in a clockwise direction as previously described. Obviously almost any degree of hydraulic force magnification can be obtained by designing the desired ratio of exposed areas of pistons I4 and 24.

Other forms and modications of the present invention both in respect of the general arrangement and the details of the respective elements will occur to those skilled in the art after reading the present description and drawings, but all such forms and modifications are intended to come within the scope of this invention as more particularly set forth in the appended claims.

I claim:

l. In a quick-acting vise, a movable stock, a xed supporting stock, a rotatable screw shaft threadediy engaging one of said stocks, a cylinder formed within the other said stool; and filled with an incompressible fluid, a piston reciprocable within said cylinder, a tubular member connecting one of said stocks and the piston within the other said stock, a ram piston carrie-d by said screw shaft and reciprocable within said tubular member, and a valve selectively operable by rotan tion of said screw shaft for by-passing the fluid in said cylinder from one side to the other side of said piston to permit quick-acting manual movement without the necessity of rotating said screw and for locking the uid in the tubular member and in that portion of the cylinder which surrounds the tubular member, .vhereby actuu ation of said ram piston can bring said stocks together under fluid pressure.

2. In a quick-acting vise, a movable stock, a iixed supporting stock, a rotatable screw shaft threadedly engaging said movable stock, a closed cylinder carried by said fixed stock and filled with an incompressible fluid, a double-faced piston reciprocable within said cylinder, a tubular member connecting said movable stock with said piston, a ram piston carried by said screw shaft and reciprocable within said tubular member, and a valve selectively operable upon rotation of said screw shaft for by-passing the fluid in said cylin der from one side to the other side of said piston in one position of said screw shaft to permit quick-acting movement without further rotation of said screw and for locking the fluid in the tubular member and in that portion oi the cylinder which surrounds the tubular member, whereby actuation of said ram piston can bring said stocks together under fluid pressure.

3. A uid-actuated quick-acting vise including a movable stock, a fixed stock, a rotatable screw shaft threadedly engaging said movable stock, a cylinder carried by said xed stock and filled with an incompressible fluid, a piston re ciprocable within said cylinder dividing said cylinder into a fluid reservoir chamber and a fluid pressure chamber, a tubular member connecting said movable stock with said piston, normally aligned ports connecting said chambers formed within said cylinder for by-passing the iiuid in said cylinder from one side to the other side of said piston for quick-acting movement of said movable stock without rotation of said screw, and valve and fluid-pressure-generating means sequentially actuated by rotation of said screw for closing said by-pass ports and drawing said stocks together by increasing the fluid pressure within said fluid pressure chamber.

4. A fluid-actuated vise including an internally threaded movable stock, a fixed stock having a cylinder carried thereby, said cylinder being filled with an incompressible fluid, a rotatable screw shaft threadedly engaging said movable stock, a piston having opposite faces being reciprocable within said cylinder, a tubular member of smaller diameter than said piston connecting said movable stock with said piston, normally aligned ports through the wall of said tubular member and through said piston providing uid communication with both faces thereof, valve means actuated by said screw shaft for closing said ports and making said piston fluidly effective, and flud-pressure-generating means actuated by further rotation of said screw shaft in the same direction for the fluid actuation of said piston in causing clamping engagement of said vise stocks.

5. A fluid-actuated vise including an internally threaded movable stock, a xed stock having a cylinder carried thereby, said cylinder being filled with an incompressible fluid, a rotatable screw shaft threadedly engaging said movable stock, a piston reciprocable within said cylinder and dividing said cylinder into two chambers, a tubular member of smaller diameter than said piston co-axially disposed about said screw shaft and connecting said movable stock with said piston, normally aligned ports through the wall of said tubular member and through said piston providing fluid communication with the chambers formed on both sides of said piston, a ported valve slidably carried by said screw shaft and actuated by said screw shaft for closing said ports and making said piston uidly effective, and fluid-pressure-generating means actuated by said screw shaft to increase effective fluidpressure upon said piston so as to cause clamping engagement of `said vise stocks.

6. A fluid-actuated vise including an internally threaded movable stock, a fixed stock having a cylinder carried thereby, said cylinder being filled with an incompressible uid, a rotatable screw shaft threadedly engaging said movable stock, a piston reciprocable within said cylinder, a tubular member connecting said movable stock with said piston, normally open lay-pass means providing fluid communication between the chambers formed within said cylinder on each side of said piston, ported valve means actuated by said screw shaft for closing said ley-pass and hydraulically locking said piston, fluid-pressuregenerating means actuated by said screw shaft and effective within one of said fluid chambers of said cylinder to actuate said piston and to force said movable stock toward said fixed stock and lost-motion means providing for continued actuation of said uid-pressure-generating means by said screw shaft while maintaining said valve means in its closed position.

7. A fluid-actuated quick-acting vise including a movable stock, a fixed stock, a rotatable screw shaft threadedly engaging one of said stocks, a closed cylinder carried by the other of said stocks and filled with an incompressible fluid, a piston within said cylinder dividing said cylinder into two chambers, a tubular member of lesser diameter than said piston connecting one of said stocks and said piston, a duid actuating ram positioned within said tubular member and connected to said screw shaft for reciprocation within said tubular member upon rotation of said screw shaft, a by-pass fluidly communicating with both said chambers for quick-acting operation of said movable stock independent of said screw shaft, said screw shaft being sequentially operable to close said by-pass to lock the fluid in one of said chambers and to actuate said ram against said locked fluid thereby moving said piston and forcing said movable stock toward said fixed stock.

8. A fluid-actuated vise including a movable stock, a fixed stock, a rotatable screw shaft threadedly engaging one of said stocks, a cylinder carried by the other said stock and filled with an incompressible fluid, a piston reciprocable within said cylinder dividing the same into a forcemultiplying chamber and a reservoir chamber, a tubular member connecting one of said stocks and said piston, portsthrough the wall of said tubular member fluidly connecting said force-multiplying chamber with the interior of said tubular member and with said reservoir chamber, a ported valve slidable on said screw shaft normally aligned with a first of said wall ports for the fluid by-passing of said piston, a second of said wall ports providing at all times uiid communication between said force-multiplying chamber and the interior of said tubular member, a ram piston carried by said screw shaft operable to create pressure against said closed ported valve within said tubular member and within said force-multiplying chamber through said second wall port for the iiuid pressure actuation of said movable vise stock.

9. A duid-actuated vise of the type set forth in claim 8 characterized by the inclusion of resilient means to maintain said lported valve in its open position wherein said piston is Icy-passed, and lost-motion means cooperable with said resilient means to maintain said ported valve in its closed position during further advance of said screw shaft and said ram piston during its .duid-pressure actuation of said movable vise stock.

KURTISS P. SCHENKE.

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

UNITED STATES PATENTS Number Date Re. 21,112 Nilson June 13, 1939 769,181 Philipp Sept. 6, 1904 976,285 Osmer Nov. 22, 1910 1,659,157 Prouty Feb. 14, 1928 2,107,970 Wells Feb. 8, 1938 2,134,780 Doyle Nov. 1, 1938 2,146,403 Nilson Feb. 7, 1939 2,343,901 Groves Mar. 14, 1944 FOREIGN PATENTS Number Country Date 16,650 Great Britain Sept. 18, 1900