US2402411A

US2402411A - Pneumatic hydraulic vise

Info

Publication number: US2402411A
Application number: US452391A
Authority: US
Inventors: Frederick W Kent
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-07-27
Filing date: 1942-07-27
Publication date: 1946-06-18
Anticipated expiration: 1963-06-18

Description

F; W. KENT PNEUMATIC HYDRAULIC visa 'Filed July 27, 1942 2 Sheets-Sheet 1 I @W W June 18, 1946; F. w; KENT v 2,402,411

I PNEUMATIC HYDRAULIC VISE k Filed July 27, 1942- 2 Sheets-Sheet 2 Patented June 18, 1946 UNITED STATES PATENT OFFICE PNEUMATIC HYDRAULIC vIsE Frederick W. Kent, Chicago, 111.. I Application July 2 7 1942, Serial No 452,391

This invention relates to improvements in a vise adapted to be mounted upon the work table of a milling machine or other machineswherein a means for holding an object to be Worked upon may be required or desirable.

The object of the invention is to provide a structure of the typespecified which is operated hydraulically to clamp the work in place, and which is equipped with interchangeable jaws to receive articles of different dimensionsand which is also provided with means for varying the spacing apart of such jaws and with means for effect ing quick release of the work when desired or necessary,

Another object of my invention is the provision of a vise in which both pneumatic and hydraulic pressure afiects the locking of the workpiece in the vise. Vises utilizing pneumatic or 8 Claims,

hydraulic pressure and particularly pneumatic 4 pressure, as a locking means, have, because of the need for variable pressure, on difierent size work-pieces resorted to a large and cumbersome cylinder or cylinders to provide the maximum pressures required. The step-up" of locking pressure of my vise eliminates this objectionable feature and a much smaller, more sturdy, compact vise, with a large work-piece capacity results.

Other objects and advantages of the invention Will be readily understood from the following description and, in part at least, are particularly pointed out therein.

A suitable embodiment of the invention is illustrated in detail in the accompanying drawings which are, in part, more or less diagrammatic in that they omit certain conventional details of construction common to fluid pressure actuated machinery.

In said drawings, a

Fig. 1 is a top plan view of the Vise constructed in accordance with the invention.

Fig. 2 is a side elevation thereof withmy parts shown in vertical longitudinal section.

The said vise comprises a baserplate it which is equipped peripherally with recesses ll, l2, l3 and M, respectively, to receive the shanks of bolts by means of which said base plate is rigidly mounted upon the frame of the machine. It is desired to call attention to the fact that the recesses H, 12,13 and I4 complement the ways of the standard milling machine carriage so that my vise may be secured thereto without special fixtures.

gTheQsaid-plate 1001s equipped with. suitable parallel guide formations l5 and IS with which the .ba'se'portions of the respective vise jaw members i5 and H are slidably engaged. The structure includes a member l8 which is rigid with the base plate and is equipped with a vertically disposed pocket 21 to receive a suitable liquid, such as oil, and is equipped at its upper end with suitable closure plugs 27a and'2lb, respectively, the latter being equipped with a stop projection 21c opposed to the end of a piston 26 which is recipro'cably movable in a passage or cylinder communicating with the pocket 21 and is rigid with the vice jaw member Iii which it actuates.

In the lower end of the member 8 there is provided a cylindrical passage 21d which receives thepiston 29 secured to the piston rod 30 of the piston 32 of cylinder 33, said piston 30 extending through the bearing 32 of the said cylinder, The passage to receive the rod 29 may be termed a cylinder which communicates at point 28 with the pocket 21,

The vise jawrmemb'ers l5 and I1 are equipped with'removable work engaging jaws 20 and M which are equipped with recesses 28' and 2! in their opposed faces and are adapted to be replacedbyother jaw elements having variously shaped recessesin which the work is to be engaged.

Rigid with the base plate 10 is a pair of flanges ltd equipped'with inwardly projecting ears lfle through which the shanks of screws 24 and '25 extend freely for movement with respect to said ears, said screws being engaged in threaded openings in the Visa jaw member i6. Compression springs 22 and 23 of suitable length and strength are interposed between the ears We and the heads of the screws and 25, or washer engaged with said heads as shown.

The cylinder 33 is'equipped with ports 33a and 43%), respectively, the former being connected with the valve casing 34 equipped with a two-way valve adapted to beflac'tliated .by the lever 35. Said valve casing is equipped with an exhaust port ait! and is connected by means of pipe 36 .with a source of supplyoi fluid under pressure,

such as air, which is admitted to the cylinder 33 when the valve is in the position shown. Said valve is adaptedtobe rotated through an arc of 90". to connect the port 33d with the exhaust port 34a to relieve pressure in the cylinder at one end of the piston 32; Obyiouslythe port 331) maybe controlled by a similar two-way valveiior actue ating the piston in the vdirection opposite to that in which it is moved when the valve of casing 34 is in the position shown.

It will be noted of course that the diameter of the piston 32 is many times that of the piston rod 29 so that the pressure exerted by the latter upon the liquid contained in the pocket 21 will be subjected to many times the pressure exerted upon the piston 32 by compressed air or other fluid entering the port 33a. This particular feature of y vise is of substantial importance since it is one of the factors which permits a substantial step-up" of the pressure exerted by the jaw |6 as compared with the fluid pressure exerted against the piston 32. Another factor that controls the step-up of pressure is the comparative length of stroke or travel of the pistons 29 and 26. Thus the "step-up of jaw pressure can be regulated without resorting to mechanical leverage or large cumbersome cylinders. As a matter of practical engineering a force of .50 to 60 times the air or fluid line Pressure is exerted at the jaws of my vise.

Rigid with the jaw member I! is a member 40 shown in section in Fig. 2, which is provided with a substantially semi-cylindrical bottom bushing threaded to engage the screw shaft 31 which is also threaded through the member |c rigidly with the base plate In and is adapted to be actuated manually by the crank arm 39. The bushing 38 is rigidly mounted in the member We as is customary.

Threaded through the top wall of the member 49 is a set screw 4| which is rotatably connected at its lower end with a substantially semi-cylindrical nut 4|a which is adapted to be clamped tightly upon the screw shaft 31 to hold the latter against rotation and thus hold the vise jaw rigidly in any position to which it may have been adjusted by rotation of the crank 39 after the nut portion 4|a relieves pressure on the screw shaft 31.

The operation of the structure above described is as follows:

It will b noted that the springs 22 and 23 operate to maintain the jaw member 20 normally in engagement with the flanges |0d and serve also to maintain the piston 26 at the rearward limit of its movement as shown in Fig. 2. If desired, however,.the stop projection 210 may be disposed to constitute the means for limiting the reverse movement or work disengaging movement of the jaw H in place of utilizing the forward edges of the members IOb as stops a aforesaid. If the springs 22 and 23 are strong enough to efiect movement of the piston 32 to the right when the valve'of casing 34 connects cylinder 33 with the exhaust port 34a, then the port 33b will not require connection with a valve as above described but will merely constitute a vent.

Assuming the piston 32 to be disposed at the right-hand limit of its movement, then by setting the valve connected with the port 331) (if such valve is provided) to the position wherein air from the lft hand chamber of the cylinder may be exhausted to atmosphere, and then positioning the valve of the casing 34 in the position shown in Fig. 2, the piston would be forced to the limit of its forward movement as determined by the engagement of the work jaw I6 with the work, it being obvious that this might be substantially any point between the ends of the cylindrical passage receiving the piston 29. The piston 29 as it is advanced in the cylindrical passage has displaced the oil, or other liquid, from said passage into the chamber 27. where the oil so displaced has in turn "actuated the piston 26 and the jaw I into engagement with the work-piece.

When this position is attained, the valve of case ing 34 may be closed by rotating it through an arc of about 45 or it may be retained in the position shown in Fig. 2 to maintain the cylinder connected with the source of fluid under pressure. With the valve in its closed position, it may be disconnected from the air pressure source, and the work-piece will still be securely gripped. Obviously, the disengagement of the valve from the fluid or air pressure source will facilitate the working of the work-piece and, in addition removes the possibility of injuring either the workpiece or the operator utilizing my vise should a fluid pressure failure occur.

When it is desired to release the work and re- 'move it, the valve of casing 34 will be rotated anti-clockwise through an arc of to connect the port 33a with the exhaust port 34a and the valve (if provided) controlling the port 3312 would then be turned to admit compressed air through said port and thus force the piston 32 back to its normal position at the right-hand end of the cylinder 33. The piston 29 is also withdrawn from the cylindrical passage and the oil of chamber 21 seeks the lower level of the cylindrical passage vacated by the piston 29 so that the pressure on piston 26 is released and the springs 22 and 23 retract the piston 26 and jaw Hi from engagement with the work-piece to the position shown in Fig. 2.

If by chance it should be necessary to move the jaw 2| to the right from the position shown in Fig. 2, the set screw 4| will be rotated to relieve pressure on the nut portion Ma and the crank 39 then rotated to cause the jaw 2| to be moved to the right. After releasing the work and replacing it with a new piece or pieces, the crank 39 will be again operated until the jaw 2| is in its desired position, the screw-shaft then clamped against rotation and thereafter the foregoing operations repeated so far as manipulation of the valve or valves is concerned. It is to be understood that the specific means for actuating the jaw 2| and of securing it in a pre-determined position is only one mechanical expedient, that other equivalent means may be substituted by persons skilled in the art, and that such changes are within my contemplation.

The drawings are diagrammatic in so far as they omit illustration of such conventional structural details as the inclusion of proper packing rings about the piston rod 30 and the piston 29 or omit stufiing boxes commonly used.

The words fluid pressure as used herein in conjunction with Or referring to the valve 34 and the cylinder 33 are to be construed as inclusive of such gases as might be used for such a pneumatic application but shall not be construed as meaning or including liquids. The specifying of oil as the hydraulic medium used in the chamber 2'! is not one of limitation, since other liquids might serve equally as well.

I claim:

1. In a vise, the combination with a bed provided with a guideway and a movable jaw mounted for reciprocation longitudinally of the guideway, of a hydraulic cylinder behind said jaw, a second hydraulic cylinder below the bed and disposed longitudinally of the guideway, a piston in the first cylinder and connected with the jaw, a conduit affording communication between said cylinders, a hydraulic liquid in the conduit and the respective cylinders, a single'stroke plunger in the second cylinder, the liquid in the cylinders and conduits being confined between said plunger and'piston, and means fcr. the reciprocation of said plunger beneath the bed to efiect longi-- tudinal movement of the jaw along the guideway.

2. The device of claim, 1 in which the means for efiecting plunger movement comprises a pneumatic cylinder and piston below the bed, the pneumatic piston being directly coupled with said plunger and the pneumatic cylinder being provided with a pneumatic pressure line and control valve means for admitting and exhausting pressure.

3. The device of claim 1 in which the means for eifecting plunger movement comprises a pneumatic cylinder and piston below the bed, the pneumatic piston being directly coupled with said plunger and the pneumatic cylinder being provided with a pneumatic pressure line and a control valve for admitting and exhausting pressure, the hydraulic cylinder below the bed-being of materially reduced cross section as compared with the hydraulic cylinder behind the jaw and the pneumatic cylinder being of large cross section in proportion to the pressure supply line, whereby a moderate pressure in the supply line will exert greatly increased pressure at the jaw.

4. A vise comprising a hollow base, a bed extending longitudinally of said base and provided with a longitudinal guideway, a first jaw adjustable longitudinally of the bed and provided with means for fixing it in adjusted position, a second jaw movable along the guideway toward and from the first jaw, a hydraulic cylinder behind the second jaw, a piston in the cylinder connected with the second jaw, means biasing the second jaw for movement along the guideway away from the first jaw, a liquid conduit leading to the hydraulic cylinder, a second hydraulic cylinder with which said conduit communicates, said second hydraulic cylinder being disposed longitudinally of the base below the bed, a plunger in the second hydraulic cylinder, said plunger and second cylinder being of materially smaller area in cross section than the hydraulic cylinder first mentioned and its piston, a pneumatic cylinder extending longitudinally of the base below the bed and of cross sectional area greatly exceeding that of the second hydraulic cylinder, a piston in the pneumatic cylinder and projecting toward said plunger, means coupling the pneumatic piston to said plunger, a pneumatic supply line, control valve means for admitting pneumatic fluid from said line to the pneumatic cylinder and for releasing pneumatic fiuid from the pneumatic cylinder, and a liquid confined in the hydraulic cylinders and communicating conduit between the hydraulic piston and said plunger, said liquid serving to transmit motion between the plunger and the second vise jaw according as the pneumatic piston is subjected to pressure or relief of pressure in the pneumatic cylinder.

5. A vise comprising a bed afiording a longitudinal guideway, a first jaw provided with means fixing it to said bed, a second jaw movable along the guideway toward and from the first jaw, hydraulic cylinder and piston means above the bed and operatively connected for actuating the sec- 6 ond jaw, a liquid conduit leading to the hydraulic cylinder and piston means from a point below the bed, a second hydraulic cylinder and piston means disposed below the bed and communicating with said conduit, the second hydraulic cylinder and piston means being materially smaller in cross-sectional area than the hydraulic cylinder and piston means first mentioned, a pneumatic cylinder and piston means below the bed and operatively connected with the second hydraulic cylinder and piston means for effecting liquid displacement therein and otherwise mechanically independent of said second hydraulic cylinder and piston means, a hydraulic liquid confined in the first and second mentioned hydraulic cylinder and piston means and the conduit therebetween, and means for admitting pneumatic fluid to and exhausting pneumatic fiuid from the pneumatic cylinder.

6. The vise set forth in claim 5 in which the first mentioned hydraulic cylinder and piston means comprises a spring biasing the piston from the cylinder in a direction to retract the second jaw respecting the first jaw of the vise.

7. In a vise, the combination with a bed providing a guideway, a first jaw having means fixing it upon said bed and a second jaw movable along the guideway to and from the first jaw, of a hydraulic cylinder behind the second jaw, a second hydraulic cylinder below the bed and disposed longitudinally of the guideway, a piston in the first cylinder connected with the second jaw, a conduit affording communication between the cylinders, a hydraulic liquid in the conduit and respective cylinders, a single stroke plunger in the second cylinder, the liquid in the cylinders and conduits being confined between the plunger and the piston, a pneumatic cylinder independent of the second hydraulic cylinder and disposed below the bed and longitudinally of the guideway, a piston in the pneumatic cylinder having a connecting rod projecting toward the second hydraulic cylinder, a coupling connecting the connecting rod of the pneumatic piston with said plunger for the operation thereof, and means including an air supply line and control valve for admitting fluid pressure to and exhausting fluid pressure from the pneumatic cylinder for acting on the piston thereof to actuate said plunger for the displacement of a hydraulic liquid from the second hydraulic cylinder and said conduit to the first hydraulic cylinder for the operation of said second jaw.

8. The device set forth in claim 7 in which the first mentioned hydraulic cylinder comprises a compression spring seated between the end of the cylinder and the piston therein and acting upon said piston in a direction to oppose the admission of hydraulic liquid to such cylinder and, upon the release of pneumatic pressure in the pneumatic cylinder to displace hydraulic liquid from the first mentioned cylinder toward the second mentioned hydraulic cylinder and thereupon to retract said second jaw along said guideway.

FREDERICK W. KENT.