Open center control valve

A valve assembly comprising:

• a first end section having:
• (i) an inlet port configured to be fluidly coupled to a source of fluid, and (ii) a first outlet port configured to be fluidly coupled to a reservoir;
• a second end section having a second outlet port configured to be fluidly coupled to the reservoir;
• a plurality of valve sections positioned between the first end section and the second end section, wherein each valve section of the plurality of valve sections comprises:
• a housing having:
• (i) a longitudinal bore, (ii) a first and second workport passages intercepting the longitudinal bore and configured to be fluidly coupled to an actuator, (iii) a first and second return passages intercepting the longitudinal bore and connected to the first outlet port and the second outlet port, (iv) an open-center passage intercepting the longitudinal bore and configured to be connected to the inlet port of the first end section, and (v) a supply passage intercepting the longitudinal bore, and
• a spool movable in the longitudinal bore to shift between:
• (i) a neutral position that allows the open-center passage to permit fluid flow from the inlet port through the open-center passage, and (ii) a shifted position that allows fluid to be diverted from the open-center passage to the supply passage, and connects the supply passage to either the first or second workport passage while connecting the other workport passage to a corresponding return passage of the first and second return passages;
• a plurality of tie-bolts traversing the plurality of valve section to couple the plurality of valve sections to each other;
• and
• a mounting plate coupled to the first end section or the second end section, wherein at least one tie-bolt of the plurality of tie-bolts interfaces with the mounting plate via a compliant washer.

A hydraulic system comprising:

• a hydraulic actuator having a first chamber and a second chamber;
• a source of fluid;
• a reservoir;
• and
• a valve assembly comprising:
• (i) a first end section having an inlet port configured to be fluidly coupled to the source of fluid and a first outlet port configured to be fluidly coupled to the reservoir, (ii) a second end section having a second outlet port configured to be fluidly coupled to the reservoir, and (iii) a plurality of valve sections positioned between the first end section and the second end section, wherein each valve section of the plurality of valve sections comprises:
• a housing having a substantially planar surface, wherein the housing comprises:
• (i) a longitudinal bore, (ii) a first and second workport passages intercepting the longitudinal bore and configured to be fluidly coupled respectively to the first and second chambers of the hydraulic actuator, (iii) a first and second return passages intercepting the longitudinal bore and connected to the first outlet port and the second outlet port, (iv) an open-center passage intercepting the longitudinal bore and configured to be connected to the inlet port, and (v) a supply passage intercepting the longitudinal bore,
• a spool movable in the longitudinal bore to shift between:
• (i) a neutral position that allows the open-center passage to permit fluid flow from the inlet port through the open-center passage, and (ii) a shifted position that allows fluid to be diverted from the open-center passage to the supply passage, and connects the supply passage to either the first or second workport passage while connecting the other workport passage to a corresponding return passage of the first and second return passages,
• a first guide pin coupled to and protruding from the substantially planar surface of the housing, and
• a second guide pin coupled to and protruding from the substantially planar surface of the housing, wherein the first and second guide pins are inserted into corresponding holes disposed in a respective housing of an adjacent valve section to align the valve section with the adjacent valve section while attaching the valve section to the adjacent valve section.