US1989235A - Positioning device for hydraulic operators - Google Patents

Description

Jan. 29, 1935. KMBALL 1,989,235

POSITIONING DEVICE FOR HYDRAULIC OPERATORS Filed Mar ch 24, 1954 INVENTOR.

Patented Jan. 29, 1935 PAr-ENT [omen POSITIONING DEVICE FOR-HYDRAULIC.

. OPERATORS,

Linwood Kimball, Danvers, assignor to Ruggles-Klingemann Mfg..C0.', Salem, Mass.

Application March 24, 1934, Serial No. #17320 5 Claims, (01. 192- 2),

My invention-relatesto a positioning device for hydraulic operators of the typedisclosed in the patent of-William J. Woods, Number-1,901,620 of March-14, 1933, or for general applicationtosin'gle acting hydraulic operated plungers in which the plungeris'biased to one of its end,positions.- f

The object of my invention is to provide a self acting brake which will-prevent, the plunger from returning to its biased position on failure of the m3 fluid pressure supply which operates the plunger and to provide magnetic means for releasing said brake. j 7

Another object is to provide dash pot means to insurea relatively slow return to the biased posi- 155 tion when the brake is released by the magnetic means.

For a more specific description of my invention, reference should be'made to the accompanying drawing and to the above mention ofpatent. The drawing shows a vertical cross section of myinnti n.

Inthe drawing the casing (10) is provided with the cover (11) which supports the motor '.(12), whichdrives the impeller, (19)v byfme'ans of the shaft (20). The piston (21). slidesjwithin the sleeve (13), and has an opening-thereinthrough which-the oil.tube, (17) extends. Supported by the, piston.(2l) are the push rods (22) and. (23), having a, bridging member (24) supportingthe worksengaging eye (25).

The operationofthe device is asfollows: When the motor (12) isenergized, the impeller (19) will rotate. The impeller forces the oil in a radial direction through the passageway (17') thus creating a pressure differential between opposite sides of the piston (21) to move it upwards in a vertical direction.

Without the application of my positioning device the motor on de-energization would cause the impeller to quickly come to a standstill and the pressure under piston (21) soon drop causing the piston to rapidly return to its initial position.

In the application of the Woods operator which I have briefly described, it is sometimes found desirable to stop the motor without having the piston (21) return to its initial biased,

position and to provide means whereby it can be positioned at any position between its limits of operation in either direction.

For the above reason I have devised effective positioning means which I will now describe.

To the work engaging eye (25) I have attached a closed dash pot cylinder (1) which is moveable up and down with the movement of piston (21). Within this cylinder is mounted a piston (2).

This piston (2) is-held stationary by means of piston rod (3) and its connection to stationary support (4). The cylinder (1) passes through a tapered opening in; stationary support (4). jA

number of ball bearings(5) are provided in the :15

Clearance spacebetween the cylinder and "the tapered opening; These ball bearings are normally wedged into thesmall end of the tapered opening by means of spring (6). The arrange-, ment being such that the upward movement of 1 the cylinder (1) dislodges these ball bearings from their closely wedged position and allows a free upward movement of the cylinder (1'), but pro vides a check or brake against any return movement when the motor (12) isde-energized;

To release this brake and, allow for the return m'ovementjasolenoid (31) is provided,v having plunger (7) operating arm (8) pivoted at position (9). This arm is yoked aroundcylinder (1 and engages a sleeve (26) at point '(27). When Q this; solenoid (3,1) is energized theplungerfl) is attracted raising, arm (8) andforcing sleeve (26) upwardpermitting the sleeve to engage the under side ofrthe ball bearings and dislodge them from their closely wedged position,,thereby re-, 25 leasingthe cylinder (1). v

Suitable current forthe operation of the solenoid and motoris supplied from main line L1 and L2; 'afltwo way switch .(28) is provided. which controlsthe operationof the solenoidand the motor 0 to position the hydraulic operator.

, The operation is as: follows; Assuming that switch (28) is thrown to make contact at (29), then the current flows from line L1 to the motor and back through switch (28) to line L2 and the hydraulic operator slowly moved upward against the dash pot action of piston (2) in cylinder (1) Assuming the switch is thrown to natural in the position shown at the completion of the upward stroke or at some intermediate position in the upward movement, then the motor (12) is stopped, and as the cylinder (1) settles downward the ball bearings are forced into the small end of the taper and lock the operator in any position which it may occupy against further downward movement.

Now, assuming it is required to return the operator to its initial or biased position, or to some intermediate lower position, then the switch (28) is thrown to make contact at (30) and current flows from line L1 to the solenoid (31) and back through switch (28) to line L2, energizing the solenoid and releasing the brake and allowing the operator to slowly return to its initial or biased position or to some intermediate lower 2 position, depending on the operation of switch (28). The work engaging eye operates the work lever (32) which is pivoted on stationary support frame (4) and point (33). To the opposite end of this lever (32) at point (34) may be attached to whatever device it is required to operate, such as valve, damper, rheostat or other like device. The return stroke of piston (21) and other moving parts to their biased position is effected by means of spring (35) plus the weight of the moving parts.

It will now be seen that I have devised a novel positioning device for hydraulic" operators, or similar pressure actuated operatives. Modifications may be made by persons skilled in the art without departing from the spirit of my invention to be included within the scope of the invention,

as defined in the appended claims.

I claim: I

1. Ihe combination with a hydraulic operator having a cylinder with a piston therein, said piston being operable between two positions and biased to one of said positions, fluid pressure actuating means for operating said piston to the other position, ofa device for positioning said operator at intermediate positions comprising an oil dash pot operatively connected with said operator and adapted to effect a slow uniform operation of said operatorin either of two directions, of a self-acting, one way brake cooperating with a movable part of said dash pot and adapted to hold said operator at any intermediate position on failure of the fluid pressure actuating means, and electric remote control means for alternately operating the fluid pressure actuating means and for. releasing said brake.

r 2. The combination with a hydraulic operator comprising a cylinder having a piston therein, said piston being operable between two end positions and biased to one of said end positions, fluid pressure actuating means for operating said piston ,toithe other end position, in a positioning] device for said operator comprising an oil dash pot adapted to effect a slow uniform motion of said operator in either direction, of a selfacting, one way brake cooperating with a movable part of said dash pot and adapted to hold said'operator at any intermediate position between the fluid pressure operated position and its biased position, and remote control means for alternately operating the fluid pressure actuating means and for releasing said brake.

3. In a positioning device for hydraulic operators comprising in combination a cylinder having a piston therein, said piston being movable between two positions, fluid pressure means to operate said piston to the other position, an oil dash pot operatively connected with said piston comprising a closed cylinder having a loosely fitted piston therein, a piston rod extending through a stufiing box at one endof said cylinder and connected with a stationary support, a stationary guide block for said dash pot cylinder having a conical interior bore and adapted to receive wedge brake members for preventing operation in the direction of the biased position, and electric remote control means for operating the fluid pressure means and for releasing said brake. 4. The combination with a hydraulic operator having a cylinder with a piston therein, said piston being operable between two positions and biased to one of said positions, fluid pressure actuating means for operating said piston to the other position, of a device for positioning said piston at intermediate positions comprising an-oil dash pot operatively connected with said piston and adapted to effect a slow uniform motion of said piston in either direction, said dash pot comprising a cylinder having a loosely fitted piston therein constituting stationary and movable elements requiring in its operation displacement .of fluid from one side of said piston to the other, a stationary guide block having a conical interior bore adapted to receive the movable part of said dash pot and to support wedge brake members for preventing operation in the direction of the biased position, and electric remote control means for alternately operating the fluid pressure actuating means and for releasing said brake.

5. The combination with a hydraulicv operator having a reciprocating movable part operated in one direction by fluid pressure and in the opposite direction by spring tension, a positioning device for said movable part comprising a closed cylinder operably connected with said movable part, a piston in said cylinder, a piston rod extending through a stufling box at one end of said cylinder and connected with a stationary support, a one-way, self acting wedge brake surrounding said cylinder and preventing the operation of said movable part in one direction by the spring tension on failure of the fluid pressure, and remote control means for alternately effecting the operation in one direction by fluid pressure and in the opposite direction by releasing said brake. LINWOOD, KIMBALL.

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