Transfer valve with dual authority control porting
Apparatus and associated methods relate to a transfer valve with dual authority control porting. The transfer valve has a hydraulic cylinder having a cylindrical wall extending between first and second ends. The cylindrical wall has hydraulic ports therethrough for facilitating operation of the transfer valve. Within the hydraulic cylinder, a bilaterally moveable spool is axially moveable between first and second positions. The bilaterally moveable spool defines hydraulic chambers within the hydraulic cylinder. In the first position, the hydraulic chambers and the hydraulic ports form a fluidly conductive path between a first source and a first application, and another between a second source and a second application. In the second position, the cavities and the hydraulic ports form a fluidly conductive path between the first source and the second application, and another between spool positioning cavities of the transfer valve and the first application.
1 . A hydraulic transfer valve with fail-safe positioning capability, the transfer valve comprising:
a hydraulic cylinder having a cylindrical wall extending between first and second ends; the cylindrical wall having a plurality of hydraulic ports therethrough including a pair of spool-controller ports, a pair of actuator-controller ports, and a pair of hydraulic-actuator ports; and
a bilaterally moveable spool axially moveable between first and second positions within the hydraulic cylinder, the bilaterally moveable spool having a plurality of sealing lands, integrally formed, which are configured to provide hydraulic seals with an interior surface of the cylindrical wall, thereby defining a plurality of hydraulic chambers within the hydraulic cylinder including a pair of spool-positioning chambers at ends of the bilaterally moveable spool, each of the pair of spool-positioning chambers in fluid communication with a corresponding one of the pair of spool-controller ports,
wherein:
the plurality of hydraulic chambers is configured to provide fluid communication between each of the pair of hydraulic-actuator ports and a corresponding one of the pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the first position,
the plurality of sealing lands configured to isolate each of the pair of hydraulic-actuator ports from a corresponding one of the pair of spool-controller ports in response to the bilaterally moveable spool being moved to the first position, and
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the pair of hydraulic-actuator ports and the corresponding one of the pair of spool-controller ports in response to the bilaterally moveable spool being moved to the second position.
2 . The transfer valve of claim 1 , wherein the plurality of hydraulic chambers includes a pair of actuator-switching chambers, each between corresponding axially adjacent pairs of the plurality of sealing lands.
3 . The transfer valve of claim 2 , wherein one of the pair of spool-controller ports is elongated and/or is a double port that is/are in fluid communication with the corresponding one of the pair of spool-positioning chambers in response to the bilaterally moveable spool being moved to the first position, and in fluid communication with both the corresponding one of the pair of spool-positioning chambers and a corresponding one of the pair of actuator-switching chambers, in response to the bilaterally moveable spool being moved to the second position, thereby facilitating both movement of the bilaterally moveable spool and positioning of the actuator that is in fluid communication with the hydraulic-actuator ports in a fail-safe position.
4 . The transfer valve of claim 2 , wherein the cylindrical wall includes a channel on an inside surface, the channel spanning a sealing land positioned between one of the pair of spool-positioning chambers and an actuator-switching chamber adjacent thereto, thereby facilitating fluid communication therebetween.
5 . The transfer valve of claim 1 , wherein the pair of actuator-controller ports is a first pair of actuator-controller ports and the pair of hydraulic-actuator ports is a first pair of hydraulic-actuator ports, the plurality of hydraulic ports further includes:
a second pair of actuator-control ports; and
a second pair of hydraulic-actuator ports,
wherein:
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the second pair of hydraulic-actuator ports and a corresponding one of the second pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the first position,
the plurality of sealing lands is configured to isolate each of the pair of hydraulic-actuator ports from a corresponding one of the pair of spool-controller ports in response to the bilaterally moveable spool being moved to the first position, and
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the second pair of hydraulic-actuator ports and the corresponding one of the first pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the second position.
6 . The hydraulic transfer valve of claim 5 , wherein the plurality of hydraulic chambers includes first, second, third, and fourth actuator-switching chambers.
7 . The hydraulic transfer valve of claim 6 , wherein the first pair of actuator-controller ports is axially positioned to be in fluid communication with the first and fourth actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the first and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.
8 . The hydraulic transfer valve of claim 7 , wherein the second pair of actuator-controller ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and blocked from fluid communication with any of the plurality of hydraulic chambers by two of the plurality of sealing lands in response to the bilaterally moveable spool being moved to the second position.
9 . The hydraulic transfer valve of claim 8 , wherein the first pair of hydraulic-actuator ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the one of the pair of spool-positioning chambers and the fourth actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.
10 . The hydraulic transfer valve of claim 9 , wherein the second pair of hydraulic-actuator ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the first and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.
11 . A hydraulic system comprising:
a hydraulic actuator configured to control position of a kinematic device;
an actuator controller configured to control position of the hydraulic actuator, thereby controlling the position of the kinematic device;
a transfer-valve controller; and
a transfer valve including:
a hydraulic cylinder having a cylindrical wall extending between first and second ends; the cylindrical wall having a plurality of hydraulic ports therethrough including a pair of spool-controller ports in hydraulic communication with the transfer-valve controller, a pair of actuator-controller ports in hydraulic communication with the actuator controller, and a pair of hydraulic-actuator ports in hydraulic communication with the hydraulic actuator; and
a bilaterally moveable spool axially moveable between first and second positions within the hydraulic cylinder, the bilaterally moveable spool having a plurality of sealing lands configured to provide hydraulic seals with an interior surface of the cylindrical wall, thereby defining a plurality of hydraulic chambers within the hydraulic cylinder including a pair of spool-positioning chambers at ends of the bilaterally moveable spool, each of the pair of spool-positioning chambers in fluid communication with a corresponding one of the pair of spool-controller ports,
wherein:
the plurality of hydraulic chambers is configured to provide fluid communication between each of the pair of hydraulic-actuator ports and a corresponding one of the pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the first position;
the plurality of sealing lands is configured to isolate each of the pair of hydraulic-actuator ports from a corresponding one of the pair of spool-controller ports in response to the bilaterally moveable spool being moved to the first position, and
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the pair of hydraulic-actuator ports and a corresponding one of the pair of spool-controller ports in response to the bilaterally moveable spool being moved to the second position.
12 . The hydraulic system of claim 11 , wherein the plurality of hydraulic chambers includes a pair of actuator-switching chambers, each between corresponding axially adjacent pairs of the plurality of sealing lands.
13 . The hydraulic system of claim 12 , wherein one of the pair of spool-controller ports is elongated and/or is a double port that is/are in fluid communication with the corresponding one of the pair of spool-positioning chambers in response to the bilaterally moveable spool being moved to the first position, and in fluid communication with both the corresponding one of the pair of spool-positioning chambers and a corresponding one of the pair of actuator-switching chambers, in response to the bilaterally moveable spool being moved to the second position, thereby facilitating both movement of the bilaterally moveable spool and positioning of the actuator that is in fluid communication with the hydraulic-actuator ports in a fail-safe position.
14 . The hydraulic system of claim 12 , wherein the cylindrical wall includes a channel on an inside surface, the channel spanning a sealing land positioned between one of the pair of spool-positioning chambers and an actuator-switching chamber adjacent thereto, thereby facilitating fluid communication therebetween.
15 . The hydraulic system of claim 11 , wherein the pair of actuator-controller ports is a first pair of actuator-controller ports and the pair of hydraulic-actuator ports is a first pair of hydraulic-actuator ports, the plurality of hydraulic ports further includes:
a second pair of actuator-control ports; and
a second pair of actuator-positioning ports,
wherein:
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the second pair of hydraulic-actuator ports and a corresponding one of the second pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the first position, and
the plurality of hydraulic chambers is further configured to provide fluid communication between each of the second pair of hydraulic-actuator ports and a corresponding one of the first pair of actuator-controller ports in response to the bilaterally moveable spool being moved to the second position.
16 . The hydraulic system of claim 15 , wherein the plurality of hydraulic chambers includes first, second, third, and fourth actuator-switching chambers.
17 . The hydraulic system of claim 16 , wherein the first pair of actuator-controller ports is axially positioned to be in fluid communication with the first and fourth actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the first and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.
18 . The hydraulic system of claim 17 , wherein the second pair of actuator-controller ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and blocked from fluid communication with any of the plurality of hydraulic chambers by two of the plurality of sealing lands in response to the bilaterally moveable spool being moved to the second position.
19 . The hydraulic system of claim 18 , wherein the first pair of hydraulic-actuator ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the one of the pair of spool-positioning chambers and the fourth actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.
20 . The hydraulic system of claim 19 , wherein the second pair of hydraulic-actuator ports is axially positioned to be in fluid communication with the second and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the first position and in fluid communication with the first and third actuator-switching chambers in response to the bilaterally moveable spool being moved to the second position.