Coaxial bidirectional spool valve
First Claim
1. A coaxial bidirectional flow control spool valve comprising a valve housing;
- a valve seat in the housing; and
a plurality of fluid flow passages in the housing;
the valve comprising, as valve elements, a spool valve and first and second bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one path to a unidirectional function and through one path from the unidirectional function, receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid path to the unidirectional function and also accept flow from the same path from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the reciprocable spool valve having side sealing surfaces, and being reciprocable in the housing between first and second limiting positions, respectively, along the valve seat;
a fluid pressure-receiving surface operatively connected to one side of the reciprocable spool valve; and
a second fluid pressure-receiving surface operatively connected to the opposed side of the spool valve;
differential fluid pressure arising from fluid flow in either direction in the fluid line applied to the first and second pressure-receiving surfaces urging the valve in opposite directions, towards or away from one of its limiting positions;
the first and second bungee followers each being disposed in the housing to be actuated in one of the limiting positions of the reciprocating spool valve, the first bungee follower being actuated by the spool valve in its first position, and the second bungee follower being actuated by the spool valve in its second position;
first and second bias means urging the first and second bungee followers, respectively, in one direction, and the spool valve urging the bungee followers in the opposite direction;
first and second flow passages in the valve housing for connection in series to opposite sides of a function and in fluid flow connection with each other via the function;
third and fourth fluid flow passages in the housing for connection in series to a fluid line, accepting fluid flow therethrough in either direction;
fluid flow connections controlled by the spool valve and bungee followers between the first fluid flow passage and each of the third and fourth flow passages; and
between the second flow passage and each of the third and fourth fluid flow passages;
one of the bungee followers and the reciprocating spool valve in one limiting position of the spool valve permitting flow through one of the fluid connections only between the third fluid flow passage and the first fluid flow passage; and
between the fourth fluid flow passage and the second fluid flow passage, and the other of the bungee followers and the reciprocating spool valve in the other of its limiting positions permitting flow through one of the fluid flow connections only between the third fluid flow passage and the second fluid flow passage, and between the first fluid flow passage and the fourth fluid flow passage, so that fluid flow in either direction through the third and fourth fluid flow passages is directed in the same direction through the first and second fluid flow passages of the housing.
1 Assignment
0 Petitions
Accused Products
Abstract
Coaxial bidirectional spool valves are provided for use in fluid systems such as hydrostat systems where flow can proceed in opposite directions, and which direct flow through a unidirectional or multidirectional function such as a filter assembly in the normal direction regardless of the direction of flow in the system. The valve includes a spool valve reciprocably movable between two limiting positions according to fluid pressure differential across the valve and engaging one of a pair of bungee followers in each position, thereby intercepting and controlling flow through a box junction of the fluid line with the lines leading to and from the filter assembly in a manner such that, regardless of the direction of flow in the fluid line, flow proceeds in the same direction in the connecting fluid lines to and from the function.
32 Citations
25 Claims
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1. A coaxial bidirectional flow control spool valve comprising a valve housing;
- a valve seat in the housing; and
a plurality of fluid flow passages in the housing;
the valve comprising, as valve elements, a spool valve and first and second bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one path to a unidirectional function and through one path from the unidirectional function, receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid path to the unidirectional function and also accept flow from the same path from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the reciprocable spool valve having side sealing surfaces, and being reciprocable in the housing between first and second limiting positions, respectively, along the valve seat;
a fluid pressure-receiving surface operatively connected to one side of the reciprocable spool valve; and
a second fluid pressure-receiving surface operatively connected to the opposed side of the spool valve;
differential fluid pressure arising from fluid flow in either direction in the fluid line applied to the first and second pressure-receiving surfaces urging the valve in opposite directions, towards or away from one of its limiting positions;
the first and second bungee followers each being disposed in the housing to be actuated in one of the limiting positions of the reciprocating spool valve, the first bungee follower being actuated by the spool valve in its first position, and the second bungee follower being actuated by the spool valve in its second position;
first and second bias means urging the first and second bungee followers, respectively, in one direction, and the spool valve urging the bungee followers in the opposite direction;
first and second flow passages in the valve housing for connection in series to opposite sides of a function and in fluid flow connection with each other via the function;
third and fourth fluid flow passages in the housing for connection in series to a fluid line, accepting fluid flow therethrough in either direction;
fluid flow connections controlled by the spool valve and bungee followers between the first fluid flow passage and each of the third and fourth flow passages; and
between the second flow passage and each of the third and fourth fluid flow passages;
one of the bungee followers and the reciprocating spool valve in one limiting position of the spool valve permitting flow through one of the fluid connections only between the third fluid flow passage and the first fluid flow passage; and
between the fourth fluid flow passage and the second fluid flow passage, and the other of the bungee followers and the reciprocating spool valve in the other of its limiting positions permitting flow through one of the fluid flow connections only between the third fluid flow passage and the second fluid flow passage, and between the first fluid flow passage and the fourth fluid flow passage, so that fluid flow in either direction through the third and fourth fluid flow passages is directed in the same direction through the first and second fluid flow passages of the housing.
- a valve seat in the housing; and
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2. A coaxial bidirectional flow control spool valve comprising a valve housing;
- and a plurality of fluid flow passages through the housing; and
, as valve elements, a spool valve and two bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one fluid flow passage to a unidirectional function and through one fluid flow passage from the unidirectional function, receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the valve and bungee follower accepting flow through the fluid line from the opposite direction, and directing flow through the same fluid flow passage to the unidirectional function and also accepting flow from the same fluid flow passage from the unidirectional function and directing this flow back into the fluid line continuing in the same opposite direction;
the spool valve being provided with fluid pressure-actuating surfaces on opposite sides so as to be responsive to fluid pressure differential across the function and the spool valve arising from flow of fluid in each of the opposite directions through the fluid line, the valve being responsive to fluid pressure differential arising from flow in one direction through the fluid line, and thereby driven against one bungee follower, and being responsive to fluid pressure differential arising from flow in the opposite direction through the fluid line, and thereby being driven against the other bungee follower;
the spool valve and bungee followers being coaxial, and having open centers constituting flow passages, the reciprocating spool valve having a septum separating the central flow passage therethrough into portions upstream and downstream of the function, so that fluid flow is provided through the fluid flow passages through the open centers of the bungee followers and separate portions of the open center of the spool valve, reciprocation of the spool valve opening or closing flow passages extending laterally of the valve through or at one end of the tubular housing. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10)
- and a plurality of fluid flow passages through the housing; and
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11. A filter assembly comprising, in combination, a fluid line arranged for fluid flow therethrough in either of two directions;
- a filter element in fluid flow connection with the fluid line, so that flow through the line in at least one direction must pass through the filter element;
the filter element having a filter sheet arranged in a closed configuration about the internal passage, with end caps across the ends of the internal passage attached to the filter sheet, at least one of the end caps having an aperture therethrough in fluid flow connection with the internal passage; and
a bidirectional spool valve in fluid flow connection with the fluid line and the filter element and responsive to differential fluid pressure thereacross arising from flow of fluid in either direction through the line and a valve flow passage to direct flow through the filter in the same direction, the bidirectional flow control spool valve comprising a valve housing;
a plurality of fluid flow passages through the housing; and
as valve elements a spool valve and two bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one fluid flow passage to a unidirectional function and through one fluid flow passage from the unidirectional function, receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the spool valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid flow passage to the unidirectional function and also accept flow from the same fluid flow passage from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the spool valve being provided with fluid pressure-actuating surfaces on opposite sides so as to be responsive to fluid pressure differential across the function and the spool valve arising from flow of fluid in each of the oppsoite directions through the fluid line, the valve being responsive to fluid pressure differential arising from flow in one direction through the fluid line, and thereby driven against one bungee follower, and being responsive to fluid pressure differential arising from flow in the opposite direction through the fluid line, and thereby being driven against the other bungee follower. - View Dependent Claims (12, 13, 14, 15)
- a filter element in fluid flow connection with the fluid line, so that flow through the line in at least one direction must pass through the filter element;
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16. A hydrostat system comprising a hydraulic pump;
- a hydraulic motor;
a fluid line operatively connecting the pump with the motor, and arranged to carry fluid flow therebetween in either direction;
a filter interposed in the fluid line between the pump and the motor, for filtration of fluid in either direction of flow from the pump to the motor; and
a bidirectional flow control spool valve in fluid flow-controlling connection with the fluid line and with fluid lines in series flow connection to and from the filter, and responsive to differential fluid pressure thereacross arising from flow of fluid in either direction through the fluid line and a valve flow passage in series with the filter to direct flow through the filter in the same direction, the bidirectional flow control spool valve comprising a valve housing;
a plurality of fluid flow passages through the housing; and
as valve elements a spool valve and two bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one fluid flow passage to a unidirectional function and through one fluid flow passage from the unidirectional function receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the spool valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid flow passage to the unidirectional function and also accept flow from the same fluid flow passage from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the spool valve being provided with fluid pressure-actuating surfaces on opposite sides so as to be responsive to fluid pressure differential across the function and the spool valve arising from flow of fluid in each of the opposite directions through the fluid line, the valve being responsive to fluid pressure differential arising from flow in one direction through the fluid line, and thereby driven against one bungee follower, and being responsive to fluid pressure differential arising from flow in the opposite direction through the fluid line, and thereby being driven against the other bungee follower. - View Dependent Claims (17, 18, 19, 20)
- a hydraulic motor;
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21. A hydrostat system comprising a hydraulic pump;
- at least one hydraulic motor;
a fluid line operatively connecting the pump with each hydraulic motor, and arranged to carry fluid flow therebetween in either direction;
a filter interposed in the fluid line between the pump and the hydraulic motor, for filtration of fluid in at least one direction of flow from the pump to the hydraulic motor, and a bidirectional flow control spool valve in fluid flow controlling connection with the fluid line and with fluid lines in series flow connection to and from the hydraulic motor, and responsive to differential fluid pressure thereacross arising from flow of fluid in either direction through the fluid line and a valve flow passage in series with the hydraulic motor, to direct flow through the hydraulic motor in the same direction, the bidirectional flow control spool valve comprising a valve housing;
a plurality of fluid flow passages through the housing; and
as valve elements a spool valve and two bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee followerin each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one fluid flow passage to a unidirectional function and through one fluid flow passage from the unidirectional function receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the spool valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid flow passage to the unidirectional function and also accept flow from the same fluid flow passage from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the spool valve being provided with fluid pressure-actuating surfaces on opposite sides so as to be responsive to fluid pressure differential across the function and the spool valve arising from flow of fluid in each of the opposite directions through the fluid line, the valve being responsive to fluid pressure differential arising from flow in one direction through the fluid line, and thereby driven against one bungee follower, and being responsive to fluid pressure differential arising from flow in the opposite direction through the fluid line, and thereby being driven against the other bungee follower. - View Dependent Claims (22, 23, 24)
- at least one hydraulic motor;
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25. A hydrostat system comprising a hydraulic pump;
- at least one hydraulic motor;
a fluid line operatively connecting the pump with each motor, and arranged to carry fluid flow therebetween in either direction;
a filter interposed in the fluid line between the pump and the motor, for filtration of fluid in at least one direction of flow from the pump to the motor; and
two bidirectional flow control spool valves, of which valve one is in fluid flow-controlling connection with the fluid line and with fluid lines in series flow connection to and from the motor, and responsive to differential fluid pressure thereacross arising from flow of fluid in either direction through the fluid line and a valve flow passage in series with the motor, to direct flow through the motor in the same direction, and the second valve is in fluid flow-controlling connection with the fluid line and with fluid lines in series flow connection to and from the filter, and responsive to differential fluid pressure thereacross arising from flow of fluid in either direction through the fluid line and a valve flow passage in series with the filter to direct flow through the filter in the same direction, each bidirectional flow control spool valve comprising a valve housing;
a plurality of fluid flow passages through the housing; and
as valve elements a spool valve and two bungee followers, each reciprocating between two limiting positions along a longitudinal axis, the spool valve moving into and away from actuating contact with a bungee follower in each of its two limiting positions, the spool valve and one of each of the bungee followers being linked in each of the limiting positions in their response to fluid flow, so that when the spool valve is in one position, it together with one bungee follower accepts flow from one direction in a fluid line and directs it through one fluid flow passage to a unidirectional function and through one fluid flow passage from the unidirectional function, receiving and returning the flow to the fluid line continuing in the same direction, and when the spool valve is in actuating contact with the other bungee follower, in the other limiting position, the spool valve and bungee follower accept flow through the fluid line from the opposite direction, and direct it through the same fluid flow passage to the unidirectional function and also accept flow from the same fluid flow passage from the unidirectional function and direct this flow back into the fluid line continuing in the same opposite direction;
the spool valve being provided with fluid pressure-actuating surfaces on opposite sides so as to be responsive to fluid pressure differential across the function and the spool valve arising from flow of fluid in each of the opposite directions through the fluid line, the valve being responsive to fluid pressure differential arising from flow in one direction through the fluid line, and thereby driven against one bungee follower, and being responsive to fluid pressure differential arising from flow in the opposite direction through the fluid line, and thereby being driven against the other bungee follower.
- at least one hydraulic motor;
Specification