Abstract:
In all hydraulic systems, it is important to remove all entrained air, dirt and other impurities from the system prior to normal operation. In the subject invention, a method of purging and/or preconditioning a hydraulic system is provided and includes the steps of connecting a shunt line between opposite ends of respective fluid actuators and operating the respective valve mechanisms to force fluid from the source of pressurized fluid through the respective valve mechanisms across the respective shunt lines and back to the reservoir. Likewise, the subject invention provides a method to purge the signal control system of any entrained air, dirt and other impurities. The method also provides an easy process of "warming up" the system or totally replacing all of the fluid in the system with another type of fluid, such as fluid for arctic conditions. The method of purging the signal control system includes selectively connecting a bypass line between the reservoir and the signal control system. The above method provides an efficient and simple way to purge a hydraulic system of entrapped air, dirt and other impurities.
Abstract:
In a hydrodynamic torque converter, an axial abutment is arranged to support friction discs of a lock-up clutch and a clutch actuator working pressure chamber accommodating an axial piston so as to move with a friction disc carrier. Together with a second friction disc carrier, the friction disc carrier torsionally holds the friction discs in alternating sequence and is also located in a centripetal flow between a pump impeller outlet and a torque converter return conduit.
Abstract:
A hydraulic drive system for a construction machine comprising a plurality of distribution compensating valves (7a, 7b) for controlling the respective differential pressures across the plurality of flow control valves (6a, 6b), the distribution compensating valves respectively having first pressure bearing chambers (52a, 52b) acting in a valve-closing direction, second pressure bearing chambers (53a, 53b) acting in a valve-opening direction, and third pressure bearing chambers (54a, 54b) acting in the valve-closing direction to reduce target values of differential pressures across a plurality of associated flow control valves (6a, 6b). The system further comprises a fourth pressure bearing chamber (55a, 55b) provided in at least one of the plurality of distribution compensating valves (7a, 7b) and subjected to a second control pressure (P.sub.CT) for acting in the valve-opening direction to set a target value (.DELTA.P.sub.T) of the differential pressure across the associated flow control valve (6a, 6b). This enables the target value of the differential pressure across the flow control valve to be freely changed whereby an allowable maximum flow rate passing through the flow control valve can be freely changed so that a maximum driving speed may be freely set dependent upon the capacity of a hydraulic actuator used and/or the forms of work to be carried out.
Abstract:
A hydrodynamic retarder has a centrally disposed chamber which is filled with hydraulic fluid and subjected to centrifugal forces. A valve mechanism, responsive to the operator, is opened by a control valve system when vehicle retarding action is requested to permit rapid filling of the retarder vane space from the centrally disposed chamber. The valve mechanism is also closed by the control valve system after a predetermined time. This accommodates fast filling of the retarder but does not permit air ingestion by the retarder. A passage, in the stationary housing portion of the retarder, is opened to the transmission pump circuit during retarding action to maintain the retarder pressure and fluid circulation for cooling. The central chamber has an air control valve to admit air to the chamber as the chamber empties of hydraulic fluid and to permit air exhaust therefrom when the chamber is refilled.
Abstract:
In a torsional damper device in particular for equipping hydraulic coupling devices, in particular for automotive vehicles, two flanges mesh through meshing means with clearance with a same flange. There is at least one area of axial interpenetration between these flanges.
Abstract:
A transmission system comprises an annular input member adapted to be keyed at least circumferentially to a first shaft. It has a generally cylindrical axial wall. A movement take-up device within this cylindrical wall has at least one protected mild steel lug by which it is keyed axially and circumferentially to the cylindrical wall and by which it is adapted to be at least circumferentially keyed to a second shaft. The movement take-up device also comprises an input part to which one end of this lug is welded, the other end of the lug being fixed to the cylindrical wall.
Abstract:
A transmission system comprises an annular input member adapted to be keyed at least circumferentially to a first shaft. This input member has a generally cylindrical axial wall and a generally transverse radial wall. A movement take-up device within the cylindrical wall has an input part by which it is keyed axially and circumferentially to the input member and adapted to be at least circumferentially keyed to a second shaft. The input part bears axially on the transverse wall. At least one dog is attached to the cylindrical wall and has at least one of its two lateral edges generally transversely disposed relative to the axis of the system and converging towards its other lateral edge in the direction towards the transverse wall. A notch in part of the input part is complementary to and interlocked with the aforementioned dog.
Abstract:
A lock-up valve includes a spool movable between a clutch engagement position wherein the lock-up clutch is engaged and a clutch release position wherein the engagement of the lock-up clutch is released. A spring biases the spool toward the clutch release position. The spool has a first pressure acting area and a second pressure acting area. A fluid pressure is applied to the first pressure acting area during operation in the m+th speed ratio (where: m is an integer) and the m+1th speed ratio to urge the spool against the spring toward the clutch engagement position. A lock-up timing valve is provided which allows the application of another fluid pressure to the second pressure acting area during shifting between the m th speed ratio and the m+1th speed ratio to urge said spool toward the clutch release position.
Abstract:
A lockup control device for a torque converter, which is provided with a lockup clutch engageable to connect a pump at the torque converter directly with a turbine thereat and disengageable to release the direct connection of the pump and turbine, and with an actuating device comprising a car speed detector which detects car speed to output a plurality of car speed signals, a negative pressure detector which detects a suction pipe negative pressure to output a plurality of negative pressure signals, and an actuator operable in response to the car speed and negative pressure signals, so that, on a basis of the car speed and negative pressure signals output from the respective detectors, the clutch is engaged when the car speed is greater than or equal to a predetermined speed and the suction pipe negative pressure is greater than or equal to a predetermined pressure, and is disengaged when the car speed is less than the predetermined speed and the negative pressure is less than the predetermined pressure.
Abstract:
A viscous coupling adapted to be positioned within the housing of a torque converter automatic transmission for use as a bypass of the torque converter and including an annular clutch lining secured to a side face of the outer peripheral portion of the coupling and a control valve assembly positioned in the outer peripheral portion to cushion the impact of engagement of the annular clutch lining with the confronting surface of the torque converter housing. The control valve assembly includes a rolling diaphragm which extends across the open end of an axially extending bore in the outer peripheral portion and is arranged to rollingly traverse the bore to successively cover or uncover a series of axially spaced leakage holes communicating with the main chamber of the torque converter and the bore. The end of the bore remote from the diaphragm communicates with the side of the coupling carrying the annular clutch lining at a location radially inwardly of the clutch lining so that, upon initial engagement of the coupling, leakage flow may occur through the leakage holes from the main chamber of the torque converter to the other side of the coupling to cushion the impact of the clutching engagement and the leakage flow is thereafter gradually cut off to apply the full clutch force as the rolling diaphragm traverses the bore to successively cover the leakage holes.