Automatic control of lockable differentials
AssigneeInternational Harvester Company
InventorsEmil F. Moreno, Ralph S. Hajek, Julius F. Marquardt
Life of this patent
Estimating the term…
Abstract
A pilot source of fluid pressure allows the engagement of a lockable differential into a locked mode in response to a pressure signal directed to it. Metering of the signal is related to the operating condition of the implements being carried by the vehicle regardless of operator initiation of the differential locking control.
Claims7
In a control circuit for use in controlling a lockable differential having a manually controlled system including a pressure supply means, a manually operated valve, a one way check valve, a lockable differential and first conduit means providing a means for communicating pressure from the pressure supply means to the differential through the manually operated valve and the one way check valve, the improvement comprising an automatically engaged differential locking system comprising:
- a peripheral equipment control lever;
- a multi position normally closed control valve being operatively linked to the peripheral equipment control lever;
- a second one way check valve permitting flow in one direction;
- second conduit means allowing communication between the pressure supply means and the lockable differential through the multiposition normally closed control valve and the second one way check valve whereby displacement of the peripheral equipment control lever will result in the opening of the multiposition normally closed control valve thus resulting in transmission of pressure from the pressure supply means to lock the lockable differential.
In combination with a control circuit for use in controlling a lockable differential having a manually controlled system including a supply source of fluid pressure, of one of either of gas or liquid, a manually operated valve, a first one way check valve, a locking clutch for locking the lockable differential and first conduit means providing a means for communicating fluid from the supply source of fluid pressure to the lockable differential through the manually operated valve and the one way check valve, the improvement comprising:
- a peripheral equipment control mechanism;
- a peripheral equipment operating mechanism of a cylinder and a piston where the piston may be displaced by fluid pressure;
- a normally closed inversion valve having a supply port receiving fluid from the supply source of fluid pressure, a central port receiving a pressure signal, a delivery port allowing fluid pressure to be communicated to the lockable differential and an exhaust port;
- a second one way check valve allowing fluid to be delivered to the lockable differential;
- and
- second conduit means allowing fluid communication between the peripheral equipment control mechanism and the inversion valve, and the inversion valve and the lockable differential which also contains the second one way check valve whereby the lockable differential will be caused to be locked when the peripheral equipment operating mechanism interrupts the fluid flow from the supply source of fluid which results in the inversion valve allowing the passage of fluid from the supply source to the locking clutch of the lockable differential.
Dependencies are inferred from the claim text.