Hydraulic valve and system

Claim 2

A valve comprising: a housing formed to include an inlet, a first outlet, a second outlet, a first passageway extending from said inlet to said first outlet, and a second passageway extending from said inlet to said second outlet; a pressure drop restriction in said second passageway; a valve plug member in said housing, mounted for movement between an at rest position in which it blocks the first passageway and the second passageway is open and a second position in which it blocks the second passageway and the first passageway is open, said valve plug member having a first transVerse surface which is sujected to the inlet pressure and an oppositely directed second transverse surface which is subjected to the pressure in the second passageway downstream of the pressure drop restriction; a selector rod movable against said valve plug member for moving it into and holding it in its second position, and movable in the opposite direction into a second position, for freeing the valve member to assume its at rest position unless moved out of such position by an unbalanced pressure force acting on its first transverse surface; and a calibrated spring in said housing exerting an endwise force on said valve member tending to move it into its at rest position, with the spring calibration being such that when the selector rod is in its second position, and there is flow through the valve, the spring force and the pressure differential across the two transverse surfaces together position the valve plug, to divide flow between the first and second passageways as necessary to maintain a substantially constant flow through the second passageway.

Claim 3

The valve of claim 1, including a fluid chamber and a communicating valve plug chamber, wherein said inlet leads into said fluid chamber, said first and second outlets both extend laterally from said valve plug chamber, said first passageway extends from said fluid chamber axially through said valve plug chamber to said first outlet, and said second passageway extends from said fluid chamber to said second outlet and crosses said valve plug chamber in the vicinity of said second outlet, and wherein said valve plug member is movable axially in said valve plug chamber between said first and second outlets.

Claim 4

The valve of claim 1, wherein said selector rod is separate from said valve plug so that when said selector rod is retracted the valve plug can be moved away from it by fluid pressure acting in opposition to said spring.

Claim 5

The valve of claim 1, wherein said selector rod includes rotary cam means which when rotated in one direction moves the selector rod against said valve plug to push it into its second position and compress said calibrated spring, and when rotated in the opposite direction moves the selector rod in the opposite direction, with the calibrated spring serving to make said valve plug member follow the selector rod throughout at least a portion of its travel.

Claim 6

The valve of claim 4, wherein said rotary cam comprises a cylindrical member including a helical peripheral groove and a fixed pin carried by a portion of the valve housing and projecting into said groove.

Claim 7

The valve of claim 4, wherein said selector rod is separate from said valve plug so that when said selector rod is retracted the valve plug can be moved away from it by fluid pressure acting in opposition to said spring.

Claim 8

The valve of claim 1, including means for varying the size of the pressure drop restriction, including control handle means situated externally of the valve housing and means for indicating the selected size of the pressure drop restriction.

Claim 9

The valve of claim 1, wherein said selector rod is axially divided into a first part having a piston head with a first transverse surface subjected to the inlet pressure and a second, oppositely directed larger transverse surface, and a second separate part that is movable against the second transverse surface or said piston, said valve further including a fluid chamber behind the second transverse surface or said piston and a third passageway for delivering fluid from said passageway into said fluid chamber, so that when the second part of said selector rod is retracted and a blockage occurs at or downstream of said second outlet, fluid from said second passageway will build up in pressure within said fluid chamber and will force the first part of said selector rod against said valve plug to move it into its second position.

Claim 10

The valve of claim 1, wherein said selector rod includes spring means normally biasing it against said valve plug, so thAt said valve plug is normally in its second position, and control means for overcoming such spring means to move said selector rod away from said valve plug.

Claim 11

A valve that is connectable into a line portion of a hydraulic circuit for a primary hydraulic powered utilization device, and is selectively operable to either direct flow of hydraulic fluid on through said circuit, or to withdraw at least some of the hydraulic fluid from said circuit, control its flow rate to a predetermined value for powering an auxiliary hydraulic powered utilization device, and then directing the withdrawn hydraulic fluid to an auxiliary hydraulic powered utilization device, said valve comprising: an inlet and first and second outlets; a first passageway leading from said inlet to said first outlet; means for connecting said inlet and said first outlet in series between adjacent line portions of a hydraulic circuit for a primary hydraulic utilization device; a second passageway leading from said inlet to said second outlet, said second passageway including a pressure drop creating restriction therein; flow control means responsive to the pressure drop across said restriction for regulating flow through said second passageway to a predetermined value for powering an auxiliary hydraulic powered utilization device, said means including a rectilinear valve member and means mounting it for movement between a first position in which it closes the second second passageway and opens the first passageway, and a second position in which it at least partially closes the first passageway and at least partially opens the second passageway, and a spring biasing said valve member towards said second position; and selector rod means for moving said valve member into, and the holding it in, said first position.

Claim 12

A valve that is connectable into a line portion of a hydraulic circuit for a primary hydraulic powered utilization device, and is selectively operable to either direct flow of hydraulic fluid on through said circuit, or to withdraw at least some of the hydraulic fluid from said circuit, control its flow rate to a predetermined value for powering an auxiliary hydraulic powered utilization device, and then directing the withdrawn hydraulic fluid to an auxiliary hydraulic powered utilization device, said valve comprising: an inlet and first and second outlets; a first passageway leading from said inlet to said first outlet; means for connecting said inlet and said first outlet in series between adjacent line portions of a hydraulic circuit for a primary hydraulic utilization device; a second passageway leading from said inlet to said second outlet, said second passageway including a pressure drop creating restriction therein; flow control means responsive to the pressure drop across said restriction for regulating flow through said second passageway to a predetermined value for powering an auxiliary hydraulic powered utilization device, said means including a rectilinear valve member and means mounting it for movement between a first position in which it closes the second second passageway and opens the first passageway, and a second position in which it at least partially closes the first passageway and at least partially opens the second passageway, and a spring biasing said valve member towards said second position; and selector rod means for moving said valve member into, and the holding it in, said first position.

Claim 13

The valve of claim 10, including a fluid chamber and a communicating valve plug chamber, weerein said inlet leads into said fluid chamber, said first and second outlets both extend laterally from said valve plug chamber, said first passageway extends from said fluid chamber axially through said valve plug chamber to said first outlet, and said second passageway extends from said fluid chamber to said second outlet and crosses said valve plug chamber in the vicinity of said second outlet, and wherein said valve plug member is movable axially in said valve plug chamber between said first and second outlets.

Claim 14

The valve of claim 10, wherein said selector rod is separate from said valve plug so that when said selector rod is retracted the valve plug can be moved away from it by fluid pressure acting in opposition to said spring.

Claim 15

The valve of claim 10, wherein said selector rod includes rotary cam means which when rotated in one direction moves the selector rod against said valve plug to push it into its first position and compress said calibrated spring, and when rotated in the opposite direction moves the selector rod in the opposite direction, with the calibrated spring serving to make said valve plug member follow the selector rod throughout at least a portion of its travel.

Claim 16

The valve of claim 13, wherein said rotary cam comprises a cylindrical member including a helical peripheral groove and a fixed pin carried by a portion of the valve housing and projecting into said groove.

Claim 17

The valve of claim 14, wherein said selector rod is separate from said valve plug so that when said selector rod is retracted the valve plug can be moved away from it by fluid pressure acting in opposition to said spring.

Claim 18

The valve of claim 10, including means for varying the size of the pressure drop restriction, including control handle means situated externally of the valve housing and means for indicating the selected size of the pressure drop restriction.

Claim 19

A selector-flow control valve, comprising: means defining a fluid chamber and a communicating valve spool chamber; an inlet port leading into said fluid chamber; a first outlet port leadiNg from said valve spool chamber; a second outlet port leading from said valve spool chamber; a valve spool in said valve spool chamber including first and second lands separated by an annular passage groove, said first land having an outer end surface exposed to said fluid chamber, and said second land having an outer end surface; a flow passageway including a restriction, extending from said fluid chamber to and through said valve spool chamber, via the passage groove in said valve chamber, to the second outlet port, said passageway including a pressure drop producing restriction between said fluid chamber and said passage groove; a spring contacting the outer end surface of said second land, said spring exerting a biasing force on said valve spool, tending to urge it towards said fluid chamber; means communicating the outer end of said second land with said flow passageway downstream of said restriction; said valve spool having a first position in which outflow from said valve is primarily through the second outlet port and such flow is regulated by the first land of said valve spool changing the effective sizes of said first and second outlet orifices upon said valve spool moving in response to pressure changes within said fluid chamber, and said first outlet port serves as a relief port for said fluid chamber; and selector rod means for moving said valve spool into a position in which the second outlet port is blocked by said first land and outflow from said valve is totally through said first outlet port.

Claim 20

A selector-flow control valve, comprising: means defining a fluid chamber and a communicating valve spool chamber; an inlet port leading into said fluid chamber; a first outlet port leadiNg from said valve spool chamber; a second outlet port leading from said valve spool chamber; a valve spool in said valve spool chamber including first and second lands separated by an annular passage groove, said first land having an outer end surface exposed to said fluid chamber, and said second land having an outer end surface; a flow passageway including a restriction, extending from said fluid chamber to and through said valve spool chamber, via the passage groove in said valve chamber, to the second outlet port, said passageway including a pressure drop producing restriction between said fluid chamber and said passage groove; a spring contacting the outer end surface of said second land, said spring exerting a biasing force on said valve spool, tending to urge it towards said fluid chamber; means communicating the outer end of said second land with said flow passageway downstream of said restriction; said valve spool having a first position in which outflow from said valve is primarily through the second outlet port and such flow is regulated by the first land of said valve spool changing the effective sizes of said first and second outlet orifices upon said valve spool moving in response to pressure changes within said fluid chamber, and said first outlet port serves as a relief port for said fluid chamber; and selector rod means for moving said valve spool into a position in which the second outlet port is blocked by said first land and outflow from said valve is totally through said first outlet port.