US2889814A

US2889814A - Pressure fluid distributor valves

Info

Publication number: US2889814A
Application number: US410953A
Authority: US
Inventors: Mercier Jean
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-01-14
Filing date: 1954-02-17
Publication date: 1959-06-09
Anticipated expiration: 1976-06-09

Description

June 9 1959 J. MERCIER l 2,889,814 PRESSURE FLUID DISTRIBUTOR` VALVES original Fileduan. 14, 1948 United States Patent C PRESSURE FLUID DISTRIBUTOR VALVES Jean Mercier, New York, N.Y.

Original application January 14, 1948, Serial No. 2,286,

now Patent No. 2,787,255, dated April 2, 1957. Divided and this application February 17, 1954, Serial No. 410,953

Claims priority, application Luxemburg January 22, 1947 3 Claims. (Cl. 121-46.5)

This invention relates to pressure fluid distributor valves comprising two coaxially aligned valves permitting a precise and undelayed opening and closing of ports or orifices controlled thereby and this is true regardless of the fluid used or the circuit in which the distributor is inserted.

The present application is a division of application, Serial No. 2,286, tiled January 14, 1948, now Patent No. 2,787,255, issued April 2, 1957.

In known distributors of this kind, the two coaxial valves are mounted within a valve casing coaxially therewith, whereby the movable member of one of the valves forms the seat for the movable member of the other valve, the displacements of which are guided by an inner wall portion of the valve casing in such a manner that this other movable valve member will engage its `seat in a more or less well centered position. When the two valves are mounted within a valve casing so that their axial displacements are guided by the casing itself, it will be necessary either to produce precise machined guiding surfaces for maintaining the two valvesA always in coaxial relation, or to provide for a transverse play permitting one of the valves to seat perfectly on the other valve when either one of the valves returns to its closed position; it is dilcult to determine in advance the exact amount of transverse play permitting the valves to center themselves on the respective seat during return movement into closed position since a too small play may be insuicient whereas a too great play may cause undesirable leakage; thus, the provision of a predetermined transverse play may be considered as a trial and error method, that is, the chosen amount of transverse play may be satisfactory in one case and unsatisfactory in another case.

The object of the present invention is to remedy these drawbacks and to provide for precision alignment of the movable valve members regardless of their transverse play or the machining of their guiding surfaces, thereby improving the structure of the distributor valve, facilitating production and minimizing its cost of manufacture.

The distributor valve construction according to the present invention will now be described by way of example with reference to the accompanying drawing which shows a iiuid pressure control system embodying two distributor valves.

In the drawing there is vshown a hydraulic control system incorporating two distributor Valves. The hydraulic control system comprises a controlled element constituted by a hydraulic motor M and a control element constituted by a lever 40 pivoted at 41 to the body of a control device including two distributors D1 and D2. Distributor D1 comprises an inlet valve 42 and an outlet valve 43, and distributor D2 an inlet valve 44 and an outlet valve 45. The inlet valve 42 of distributor D1 controls the communication between a lpressure liquid supply conduit 46 and a conduit 47 leading to the left side of motor M, whereas the inlet valve 44 of distributor D2 controls the communication between said supply conduit 46 and a conduit 48 leading to the right side of Fatented June 9, 1959 motor M. The outlet valve 43 of distributor D1 controls the communication between the conduit 47 and a discharge or exhaust conduit 49, and the outlet valve 45 of distributor D2 the communication between the conduit 48 and said discharge conduit 49. The inlet valves 42 and 44 are constantly urged towards their corresponding seats by spring members 50 and 51, respectively, and the outlet valve 45 of distributor D2 is maintained in abutting contact with the rod of a piston 52 mounted in a cylindrical chamber formed in the body of distributor D2. The space 57 of this cylindrical chamber at the right side of piston 52 may be connected through ducts 53, 54 and 55 and distributor D1 either with the pressure liquid supply conduit 46 or with the discharge conduit 49. A spring 56 is yarranged in the cylindrical chamber to urge piston 52 constantly towards the outlet valve 45.

The operation of the control system can be easily understood:

When the lever 40 occupies the position shown in the drawing the pressure liquid supplied through the conduit 46 iiows through the open inlet valve 44 of distributor D2 and conduit 48 to the right side of motor M, while the `left side of this motor is connected, through conduit 47 and the open outlet valve 43 of distributor D1, with the discharge conduit 49. But when the upper end of lever 40 is displaced from left to right so as tot close the outlet valve 43 of distributor D1 to therebyinterrupt the communication between the left side of motor' M1 and the discharge conduit 49, the liquid coming from containing the piston 52 so as to push the latter against the action of springl 56' toward the 'outer end of the cylindrical chamber. Spring 51 is thus allowed to. close the inlet valve 44 of distributor D2 so that the two distributors of the control device are in neutral, i.e. closed position. When lever 40 is further actuated to open the inlet valve 42 of distributor D1 in order to connect the left side of motor M and the space 57 of the auxiliary chamber of distributor D2 with the pressure liquid supply conduit 46, the piston 52 will be further displaced to the left to allow the outlet valve 45 of distributor D2 to open under the action of the pressure liquid coming from the right side of motor M so that this liquid can discharge through conduit 49.

As it has been mentioned above, the improved distributor valves according to the invention may be used with any pressure uid and any circuit, but are particularly applicable to be used as pressure reducing valves and in hydraulic transmission or control systems comprising a slave unit with a lfollow-up action to bring the movable member of the slave unit to a position corresponding exactly to that occupied by a valve actuating member, the distributor valves permitting not only to reproduce exactly the displacements of the movable part of the distributor by the slave unit with an absolute precision and without any time lag, but also to ensure at all times a perfect fluid-tight closing of the aligned valves due to their exact concentricity with respect to each other.

What is claimed is:

1. A control device for a fluid motor, comprising, in combination, a casing formed with a first valve chamber and a second valve chamber, said rst valve chamber having an inlet port, an outlet port and a take-oil port communicating with one side of said iiuid motor, and said second valve chamber having an inlet port communicating with the inlet port of said rst valve chamber, an outlet port communicating with the outlet port of said iirst valve chamber, and a take-ott port communicating with the other side of said Huid motor, a valve seat formed in each valve chamber between said inlet ports and said take-off ports, respectively, a movable valve'member in each chamber cooperating with said valve seat thereof to constitute an inlet valve, an outlet valve in each chamber arranged in alignment with :the vcorresponding inlet k'valve andfhaving a "closure member adapted 'to 'cooperate with Aa seat formed'on 'the corresponding movable valve member, a passagein each inlet valve controlled by thecorr'esponding outlet valve, a bore formed 'in said casing 'in align ment with said iirst valve chamber, 'a pistonfslidable in said bore and 4having its Working face formed 'with an aXial .projectionextending linto said rst valve chamber so as `to`contact the outlet valve therein, resilient means in said bore arranged t'o urge said piston in a direction in'Which-said extension opens said inlet valve inltheffirst valve chamber without moving the outlet valve 'in said first -valve chamber ofits seat, a passageway in said-casing for interconnecting the space of'said borein'fr'ont of said workingface ofthe piston with the talte-o port of said second valve chamber, -and valve actuating means adapted to open one of the valves in said second valve chamber Withoutmoving the other valve of its seat, whereby said space in front of the working face of said piston will be connected either with the inlet -port or with the outlet port of said second valve chamber and the 'valves in said iirst valve chamber actuated through said piston so as tocontrol the operation of said Huid motor in accordance with the control motion of said valve actuating means.

2. A device as delined in claim l wherein said valve actuating means includes a bore in said casing in alignment with said second chamber, a cylinder slidably mounted in said last-mentioned bore and having Va recess in one side thereof, said cylinder bearing vagainst the outlet valve in said second chamber, and a lever -ipivotally mounted in said casing and having its inner end engaged and a second valve chamber, each valve chamber having an inlet port means, an outlet port means and/a take-ott port means, iirst movable valve means arranged in said first valve chamber to selectively provide an inlet passage between said inlet port means and said take-0E port means or an outlet passage ibetween said take-oi port means and said outlet port means of said irst valve chamber, resilient means in said casing to urge said viirst valve means in one direction to close-said outlet passage and to open said inlet passage, second movable valve means arranged in said secondvalve 'elia'mberto selectively .provide an inlet passage between the inlet port means and the take-off port means or an outlet passage between the take-01T port means and the outlet port means of said second valve chamber, uid pressure responsive means associated with said tirst valve means and communicating with the take-off port means of said second valve chamber to move said first valve means in the opposite direction against the'actionof said resilient means inresponse to iluid pressure in the :take-ott port means of said second valve chamber, to thereby close the inlet 'passage and `open the outlet `passage in said rst 'valve chamber, and valve actuating -means adapted to operate said second valve means so as to open either the inlet passage for the outlet passagein said'second valve chamber.

References Cited in the file of this patent UNITED STATES PATENTS