Dana Corporation

Eaton Corporation

Robert David Jacobson

Tam Chi Huynh

Nathan Harold French

Christopher M Lodermeier

Brian W Behm

A relief valve assembly () for use with first () and second () conduits, one communicating high pressure. The assembly comprises a housing () defining first () and second () ports, and a poppet seat (). A poppet member () and the housing define a spring chamber (), and a spring () is disposed to bias the poppet member toward the seat. The poppet member defines a shuttle cavity (), a shuttle passage () communicating from the cavity to the spring chamber, and the poppet defining a seat (), and a fluid passage (P) communicating with the first port, and a seat (), and a second fluid passage () communicating with the second port. A shuttle valve assembly () is provided, whereby the fluid pressure in whichever of the ports is at lower pressure is communicated to the spring chamber and adds to the force of the biasing spring.

Cross-over relief valve assembly for use in bi-directional circuit

A push-pull coupling for coupling a valve spool to a coaxial cable includes a lost-motion connection which operatively disconnects the coaxial cable from the valve spool when in a first mode and positively connects the coaxial cable to the valve spool when in a second mode. Switching from the first mode to the second mode is accomplished by energizing an electromagnetic actuator within the coupling which locks components to one another to transmit push and pull motion. When the actuator is deenergized, the components move relative to one another, disconnecting the coaxial cable from the valve spool. The push-pull coupling is used in hydraulic machines to prevent operation of hydraulic cylinders when a driver is not seated on the machine so as to close a seat operated switch which energizes the electromagnetic actuator.

Push-pull coupling

In order to achieve repeatable, consistent operation of a counterbalance valve, a poppet valve element within the valve has a radial bore therein in communication with a control fluid port and an axial bore therein which receives a rod that is anchored to a poppet valve cage that surrounds the poppet valve element. The poppet valve element is urged by a spring into engagement with a valve seat and pilot pressure is applied in opposition to the spring. By virtue of this arrangement, control fluid pressure is applied via the rod directly to the valve body in which the poppet valve element and cage are mounted. By changing the diameter of the rod and axial bore through the poppet valve element which receives the rod, the relief set pressure can easily be changed.

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Saint Paul, MN, United States of America

Robert David Jacobson