Abstract: A sealing structure capable of reducing oil leakage while preventing the oil from being deteriorated by a temperature rise of the oil. The sealing structure is configured to seal a clearance between two members tightly by a seal ring interposed therebetween. The seal ring is provided with a slidable structure, which is configured to seal the clearance between the two members by a hydraulic pressure applied thereto, and to unseal the clearance between the two members by a relative movement thereof resulting from a thermal expansion thereof.

Abstract: A hydraulic circuit and a hydraulic control system for preventing fluid leakage and power loss resulting from jamming of contaminants. A first circuit section has an accumulator for storing hydraulic pressure, and a control valve for controlling a passage for delivering fluid from the accumulator to an actuator. Fluid discharged from an oil pump is delivered continuously to a second circuit section. A first filter is disposed on a passage for delivering the fluid from the oil pump to the accumulator for the purpose of removing contaminants finer than those in the fluid to be delivered to the second circuit section from the fluid to be delivered to the accumulator.

Abstract: A hydraulic control system for an automatic transmission can improve a response and a controllability of the automatic transmission without increasing actuation frequency of the automatic transmission. The hydraulic control system is applied to an automatic transmission adapted to vary a torque capacity of a transmission member by an actuator. The hydraulic control system includes: a discharging device that discharges compressible gas entrained in the hydraulic fluid in the actuator; an interrupting device that interrupts power transmission; an entrainment determining device that determines an entrainment of the compressible gas in the hydraulic fluid; a disconnecting device that disconnects the power transmission by the interrupting device in case an entrained compressible gas is determined; and a discharging device that removes the entrained compressible gas from the hydraulic fluid by rotating the actuator while interrupting the power transmission.

Abstract: In a lubricating device, as a clutch engagement pressure increases, the degree of opening of a flow rate adjusting valve is mechanically increased. Thus, as the clutch engagement pressure increases, the flow rate of an oil sucked from an oil pan to a suction portion of a jet pump is increased. Therefore, as the clutch engagement pressure increases, the flow rate of the oil ejected from an ejection portion of the jet pump is increased. That is, as the clutch engagement pressure increases, the flow rate of the oil for lubricating a lubrication portion of a friction clutch is increased. Accordingly, even if a torque/oil flow rate conversion mechanism, for example, a torque sensor is not used, the flow rate of the oil ejected from the jet pump can be changed only by a flow rate adjusting valve.

Abstract: A hydraulic control system comprises: a regulator valve, which regulates a fluid pressure established by an oil pump to an operating pressure required in a control circuit; a signal pressure establishing valve, which applies a signal pressure to the regulator valve to determine a level of the fluid pressure to be established by the regulator valve; and an accumulator, which accumulates the operating pressure to be applied to the control circuit.

Abstract: A hydraulic control system adapted to carry out a speed change in case of rotating a wrapping transmission under the situation where solenoid valves for controlling a pressure in a hydraulic chamber cannot be energized. A pair of pulleys individually provided with hydraulic chambers to vary a width of a groove holding a belt. Those hydraulic chambers are connected with a hydraulic source through electrically controlled feeding control valves, and also connected with drain portions through electrically controlled relief control valves. The hydraulic control system includes a communicating passage connecting the hydraulic chambers, and the hydraulic control system disconnects the hydraulic chambers from the hydraulic source and the drain portions in case none of the feeding control valves and the relief control valves can be energized.

Abstract: A hydraulic control unit provided with oil pumps includes a first oil discharging outlet and a second oil discharging outlet, a high pressure route connected with the first oil discharging outlet, a medium pressure route with an oil pressure therein being lower than that in the high pressure route, a low pressure route with an oil pressure therein being lower than that in the medium pressure route, and a connection mode switching mechanism for selectively connecting a second oil discharging outlet with the high pressure route, the medium pressure route or the low pressure route. The connection mode switching mechanism includes a changeover valve selectively connecting the second oil discharging outlet with the medium pressure route or the low pressure route; and a changeover valve controlling device connecting the second oil discharging outlet with any of the medium pressure route and the low pressure route. The hydraulic control unit can minimize drive loss of an oil pump.

Abstract: To provide a lubricating device which can be made compact. In a lubricating device 1-1, as a clutch engagement pressure increases, the degree of opening of a flow rate adjusting valve 13 is mechanically increased. Thus, as the clutch engagement pressure increases, the flow rate of an oil sucked from an oil pan 12 to a suction portion 11b of a jet pump 11 is increased. Therefore, as the clutch engagement pressure increases, the flow rate of the oil ejected from an ejection portion 11d of the jet pump 11 is increased. That is, as the clutch engagement pressure increases, the flow rate of the oil for lubricating a lubrication portion 20a of a friction clutch 20 is increased. Accordingly, even if a torque/oil flow rate conversion mechanism, for example, a torque sensor is not used, the flow rate of the oil ejected from the jet pump 11 can be changed only by a flow rate adjusting valve 13. With the configuration, the device can be made compact.

Abstract: A home position sensor, which constitutes a portion of a home position storage unit, stores a home position by means of previously detecting the position of a printing cylinder cam. Accordingly, a printing cylinder comes to a stop at a plate replacement position at the time of replacement of a plate even when the printing cylinder cam does not pass by the home position sensor.

Abstract: A hydraulic control unit provided with oil pumps includes a first oil discharging outlet and a second oil discharging outlet, a high pressure route connected with the first oil discharging outlet, a medium pressure route with an oil pressure therein being lower than that in the high pressure route, a low pressure route with an oil pressure therein being lower than that in the medium pressure route, and a connection mode switching mechanism for selectively connecting a second oil discharging outlet with the high pressure route, the medium pressure route or the low pressure route. The connection mode switching mechanism includes a changeover valve selectively connecting the second oil discharging outlet with the medium pressure route or the low pressure route; and a changeover valve controlling device connecting the second oil discharging outlet with any of the medium pressure route and the low pressure route. The hydraulic control unit can minimize drive loss of an oil pump.

Abstract: A home position sensor, which constitutes a portion of a home position storage unit, stores a home position by means of previously detecting the position of a printing cylinder cam. Accordingly, a printing cylinder comes to a stop at a plate replacement position at the time of replacement of a plate even when the printing cylinder cam does not pass by the home position sensor.