Hydraulic control valve

Claim 2

A fluid control valve, comprising: a valve body having inlet and outlet pressure ports, return Ports, and internal passages interconnecting said ports; a movable primary valve member disposed within said body between said inlet and return ports and movable to control fluid flow through the same and from such ports to certain of said passages; a pair of check valves removably mountable in said body, each between at least one of said internal passages and at least one of said outlet ports, said check valves each having a closure member and means biasing the same toward a closed position against the flow path from said passages to said one outlet port; and an actuator means exposed to pressure from fluid in other internal passages and movable in response to such fluid pressure to open said check valve closure members to permit reverse flow therethrough; each of said check valves in said pair disposed in flow communication between different internal passages and outlet ports, and a dummy structure having a size and shape which at least in part corresponds to that of at least one of said check valve bodies and interchangeably mountable therewith, said dummy structure including biasing means for moving said actuator member.

Claim 3

The valve of claim 1, wherein each of said check valves is disposed generally adjacent said actuator means and each is openable by the latter.

Claim 4

The valve of claim 2, wherein said check valves in said pair thereof are disposed opposite one another for opposite opening operation upon oppositely directed movement of said actuator means.

Claim 5

The valve of claim 1, wherein each of said check valves has a body having substantially the same size and shape as the body of the other such valve, said bodies being interchangeable.

Claim 6

The valve of claim 1, wherein said primary valve member comprises a spool valve.

Claim 7

The valve of claim 5, including means for centering said spool in the absence of displacement forces applied thereto.

Claim 8

The valve of claim 1, including means for returning said actuator member to a neutral position, wherein said check valve is not actuated open by said member, upon removal of said fluid pressure.

Claim 9

The valve of claim 1, including means for returning said actuator member to a centered position generally intermediate the allowable movement of such member in the absence of fluid pressure applied to said member.

Claim 10

The valve of claim 8, wherein said primary valve member comprises a spool valve.

Claim 11

The valve of claim 9, including means for centering said spool in the absence of displacement forces applied thereto.

Claim 12

A fluid control valve, comprising in combination: a layered, stacked valve body structure comprising at least two separate and distinct component control valve assemblies connected together in mating juxtaposition; each of said component control valve assemblies including a valve body having openings therein which register with those of the other such body, providing fluid transfer conduits from one body to the other; said two said component valve assemblies each having an inlet for fluid under pressure, an internal passage and a primary internal valve element for opening and closing a transfer path between said inlet and said internal passage; each component valve assembly further having a secondary valve means, for opening a fluid path from said internal passage to an outlet passage of such valve assembly in response to fluid pressure present in such internal passage resulting from the operation of said primary valve element and exceeding a predetermined fluid pressure at said outlet, and for closing said fluid path in response to fluid pressure at said outlet passage which is in excess of a predetermined fluid pressure at said internal passage; a pressure plate member also joined in juxtaposition to one of said component valve assemblies and having openings disposed in registration with certain of the said openings of such component valve assembly which register with like openings of the other of said assemblies for fluid transfer between the pressure plate member and sAid one component valve assembly, said pressure plate member including a bypass valve means in communication with at least one of said openings disposed in registration with said valve assembly openings, for bypassing fluid pressures from the latter which exceed a predetermined value; said one component valve assembly having said primary valve element including a pair of internal passages and a pair of outlet passages, and said primary valve element being movable to open and close a fluid flow path through either of such internal passages; said secondary valve means of such component valve assembly having means for opening and closing a fluid path to either of said outlet passages from a respective one of said internal passages under the stated fluid pressure conditions.

Claim 13

A fluid control valve, comprising in combination: a layered, stacked valve body structure comprising at least two separate and distinct component control valve assemblies connected together in mating juxtaposition; each of said component control valve assemblies including a valve body having openings therein which register with those of the other such body, providing fluid transfer conduits from one body to the other; said two said component valve assemblies each having an inlet for fluid under pressure, an internal passage and a primary internal valve element for opening and closing a transfer path between said inlet and said internal passage; each component valve assembly further having a secondary valve means, for opening a fluid path from said internal passage to an outlet passage of such valve assembly in response to fluid pressure present in such internal passage resulting from the operation of said primary valve element and exceeding a predetermined fluid pressure at said outlet, and for closing said fluid path in response to fluid pressure at said outlet passage which is in excess of a predetermined fluid pressure at said internal passage; a pressure plate member also joined in juxtaposition to one of said component valve assemblies and having openings disposed in registration with certain of the said openings of such component valve assembly which register with like openings of the other of said assemblies for fluid transfer between the pressure plate member and sAid one component valve assembly, said pressure plate member including a bypass valve means in communication with at least one of said openings disposed in registration with said valve assembly openings, for bypassing fluid pressures from the latter which exceed a predetermined value; said one component valve assembly having said primary valve element including a pair of internal passages and a pair of outlet passages, and said primary valve element being movable to open and close a fluid flow path through either of such internal passages; said secondary valve means of such component valve assembly having means for opening and closing a fluid path to either of said outlet passages from a respective one of said internal passages under the stated fluid pressure conditions.

Claim 14

The valve of claim 11, wherein each of a plurality of said component valve assemblies includes said internal passages, said outlet passages and said secondary valve means.

Claim 15

The valve of claim 12, wherein each of a plurality of said component valve assemblies includes means defining an inlet passage, and includes a primary internal valve element for opening and closing a transfer path between such inlet passage and at least one of said internal passages.

Claim 16

The valve of claim 13, wherein said means defining said inlet passages of said plurality of component valve assemblies comprises at least one of said registering valve body openings.

Claim 17

A fluid control valve assembly, comprising in combination: a valve body having first and second internal chambers, an inlet passage communicating through part of said body to said first chamber; an outlet passage communicating through part of said body to said second chamber, and an internal passage; a spool valve movably disposed in said first chamber and having recessed portions for opening a fluid flow path from said inlet passage to said internal passage; check valve means disposed in said second chamber for opening a flow path from said internal passage to said outlet passage in response to fluid pressure at the former exceeding a predetermined pressure at the latter and for closing such flow path under opposite pressure conditions; said body having a chamber for an actuator member generally adjacent said check valve means and an internal passage from said first chamber to said actuator chamber; an actuator member disposed in said actuator chamber for movement in response to fluid pressure in such internal chamber; said actuator having a portion engageable with said check valve means to open the same in response to said actuator movement thereby relieving fluid pressure from said outlet through said check valve despite the existence of said opposite pressure conditions; said second internal chamber having a pair of second chamber portions, with a separate internal passage from said first chamber to each such chamber portion, and with an outlet passage for each such chamber portion; said spool having recessed portions for opening a flow path to either of said internal passages and to the respective second chamber portion communicating therewith; a check valve means disposed in each of said second chamber portions for opening and closing a fluid flow path from the respective separate internal passages to the respective outlet passages of such chamber portions; and said actuator chamber disposed between said second chamber portions, with said actuator member being movable toward either of said check valve means and being engageable with either of the same to open either to produce said fluid pressure relief; and a dummy check valve having means for interchangeable mounting of the same with one or the other of said check valve means; said dummy check valve having a configuration such that when so mounted the flow path through that check valve position is continuously closed.

Claim 18

A fluid control valve assembly, comprising in combination: a valve body having first and second internal chambers, an inlet passage communicating through part of said body to said first chamber; an outlet passage communicating through part of said body to said second chamber, and an internal passage; a spool valve movably disposed in said first chamber and having recessed portions for opening a fluid flow path from said inlet passage to said internal passage; check valve means disposed in said second chamber for opening a flow path from said internal passage to said outlet passage in response to fluid pressure at the former exceeding a predetermined pressure at the latter and for closing such flow path under opposite pressure conditions; said body having a chamber for an actuator member generally adjacent said check valve means and an internal passage from said first chamber to said actuator chamber; an actuator member disposed in said actuator chamber for movement in response to fluid pressure in such internal chamber; said actuator having a portion engageable with said check valve means to open the same in response to said actuator movement thereby relieving fluid pressure from said outlet through said check valve despite the existence of said opposite pressure conditions; said second internal chamber having a pair of second chamber portions, with a separate internal passage from said first chamber to each such chamber portion, and with an outlet passage for each such chamber portion; said spool having recessed portions for opening a flow path to either of said internal passages and to the respective second chamber portion communicating therewith; a check valve means disposed in each of said second chamber portions for opening and closing a fluid flow path from the respective separate internal passages to the respective outlet passages of such chamber portions; and said actuator chamber disposed between said second chamber portions, with said actuator member being movable toward either of said check valve means and being engageable with either of the same to open either to produce said fluid pressure relief; and a dummy check valve having means for interchangeable mounting of the same with one or the other of said check valve means; said dummy check valve having a configuration such that when so mounted the flow path through that check valve position is continuously closed.

Claim 19

The valve of claim 15, wherein said pair of second chamber portions comprise a bore through part of said valve body, said check valve means disposed in opposite sides of such bore.

Claim 20

The valve of claim 16, wherein said check valve means each include a body having means for removably mounting same within said bore.

Claim 21

The valve of claim 16, wherein said actuator chamber comprises a further part of said bore, said actuator member being disposed within said bore between said check valve means.

Claim 22

The valve of claim 15, wherein said dummy check valve includes means for biasing said actuator member toward a centered position.

Claim 23

A fluid control valve, comprising: a valve body having inlet and outlet pressure ports, return ports, and internal passages interconnecting said ports; a movable primary valve member disposed within said body between said inlet and return ports and movable to control fluid flow through the same and from such ports to certain of said passages; a pair of check valves mounted in said body, each between at least one of said internal passages and at least one of said outlet ports, said check valves each having a closure member and means biasing the same toward a closed position against the flow path from said passages to said one outlet port; an actuator means exposed to pressure from fluid in other internal passages and means being movable in response to such fluid pressure to open said check valve closure members to permit reverse flow therethrough; and fluid pressure by-pass means coupled to said body and having passages in flow communication with said inlet and return ports and passages in flow communication between at least certain of said internal passages; said by-pass means including pressure-responsive valve means in different ones of said passage for causing fluid flow from said inlet to said return ports and from one to another of said internal passages in response to predetermining pressure differential conditions occurring therebetween, to thereby relieve such conditions.

Claim 24

A fluid control valve, comprising: a valve body having inlet and outlet pressure ports, return ports, and internal passages interconnecting said ports; a movable primary valve member disposed within said body between said inlet and return ports and movable to control fluid flow through the same and from such ports to certain of said passages; a pair of check valves mounted in said body, each between at least one of said internal passages and at least one of said outlet ports, said check valves each having a closure member and means biasing the same toward a closed position against the flow path from said passages to said one outlet port; an actuator means exposed to pressure from fluid in other internal passages and means being movable in response to such fluid pressure to open said check valve closure members to permit reverse flow therethrough; and fluid pressure by-pass means coupled to said body and having passages in flow communication with said inlet and return ports and passages in flow communication between at least certain of said internal passages; said by-pass means including pressure-responsive valve means in different ones of said passage for causing fluid flow from said inlet to said return ports and from one to another of said internal passages in response to predetermining pressure differential conditions occurring therebetween, to thereby relieve such conditions.

Claim 25

The valve of claim 20, wherein said pressure bypass means is disposed within a pressure block member which is connected to said valve body.

Claim 26

The valve of claim 20, wherein said pressure bypass means includes adjustable means for varying the pressure level at which said relieving takes place.