Abstract:
A hydraulic valve assembly includes a pressure compensating valve in which a compensator spool is slideably received in a bore. A pre-compensator gallery connected to a metering orifice, a preload gallery leading to a hydraulic actuator, an auxiliary pump supply passage, and a load sense passage all open into the bore. The compensator spool moves in response to a pressure differential between the pre-compensator gallery and the load sense passage. That movement selectively opens and closes a first path between the pre-compensator gallery and the a preload gallery, and a second path between the auxiliary supply passage and the load sense passage. Control of these paths maintains a constant pressure drop across the metering orifice and generates a pressure signal that is employed to regulate pressure at an outlet of a pump.
Abstract:
The present invention relates to an apparatus operating a hydraulic actuator for valve, which can manually operate the hydraulic actuator for opening and closing the valve by which a flow rate is adjusted. According to the present invention, by manually operating the hydraulic actuator for opening and closing the valve, there is an advantage of manually opening and closing the valve and thus easily adjusting a flow rate of fluid flowing in a pipe, even when power is cut off. Further, according to the present invention, the hydraulic actuator for opening and closing the valve can be selectively connected with a hydraulic power pack so as to automatically open and close the valve using the hydraulic power pack according to a user's selection, or which can manually open and close the valve.
Abstract:
The invention discloses a hydraulic control arrangement for controlling a number of consumers, particularly of a mobile working machine. In addition to the consumers of the control arrangement, an additional consumer should be able to be connected to a power beyond port. All consumers and power beyond consumers are supplied with hydraulic fluid by a pump. An input pressure scale is provided downstream of the pump, and the greater of the load pressures of the consumers or of the at least one power beyond consumer is applied to the control port of said input pressure scale.
Abstract:
A hydraulic arrangement is provided for a tool locking device of a loader. The hydraulic arrangement comprises a hydraulic cylinder with first and second chambers, which cylinder has a first position for unlocking and a second position for locking, a first supply line hydraulically connected to the first chamber, a second supply line hydraulically connected to the second chamber and a control valve hydraulically connected to the first chamber. So as to prevent the faulty actuation of the hydraulic cylinder, it is proposed that the control valve has a first position and a second position, the control valve in the first position allowing hydraulic fluid to flow only in the direction of the first chamber and in the second position allowing hydraulic fluid to flow both to the first chamber and out of the first chamber and the control valve being controlled such that it assumes the first position when the hydraulic cylinder assumes its first position. In order to bring the hydraulic cylinder from the second position to the first position, the control valve always has to be moved to the second position first.
Abstract:
A mine door installation has a frame installed in a mine passageway. At least one door leaf is mounted on the frame for swinging movement between open and closed positions. Movement of the door leaf is powered by a pneumatic actuator. A pneumatically-powered control system may be provided to control the door installation. The pneumatic control system may comprise a calibrated vent to shorten the delay in the response of the door leaf to direction from the control system to stop moving. The pneumatic control system may also comprise a limit valve to prevent the door installation from opening when a second door installation is open, thereby preventing both door installations in an air lock from being open at the same time.
Abstract:
An anti-reaction valve device is configured to open such that a plunger and a sheet member move away from each other in association with first and second set difference pressures. Two anti-reaction valve devices are provided between two pipes fluidically connected to a hydraulically powered actuator such that directional relationship of connection of primary and secondary ports is reversed between the two anti-reaction valve devices so that a reaction of the actuator is inhibited quickly and reliably. A one-way valve means is positioned between the secondary port and an open and close control chamber within which the plunger and the sheet member are movable into contact with and away from each other and serves to inhibit a back flow of a hydraulic fluid. The one-way valve means is capable of inhibiting the plunger and the sheet member from moving away from each other undesirably, and hence malfunction of the anti-reaction valve devices.
Abstract:
There is provided a hydraulic control device for an automatic transmission, which is comprised of an engagement state determining section and a protection control section. If the engagement state determining section determines that each clutch, which is supplied with a line pressure via a regulating valve having a spool and has an oil pressure switch disposed in an oil channel, is held in an engaged state when gears are not changed, the protection control section sets a command pressure for the regulating valve to a protective oil pressure lower than the line pressure. This brings the regulating valve into a pressure-regulating state to cause lands of the spool to form apertures that reduce hydraulic vibration applied to the line pressure. This inhibits an oil pressure beyond an acceptable value from being applied to the oil pressure switch, and therefore improves the durability of the oil pressure switch.
Abstract:
An insert or cartridge that fits into a cavity in a valve body provides a check valve function and an anti-cavitation function and a pressure relief function. This insert is substantially circular and has an internal cavity with a valve assembly that has two pairs of valve seats, one pair of valve seats providing the anti-cavitation function and the other pair of valve seats providing the pressure relief function. The outside of the insert itself engages with a sealing surface in the cavity in the valve body to provide the check valve function.
Abstract:
An insert or cartridge that fits into a cavity in a valve body provides a check valve function and an anti-cavitation function and a pressure relief function. This insert is substantially circular and has an internal cavity with a valve assembly that has two pairs of valve seats, one pair of valve seats providing the anti-cavitation function and the other pair of valve seats providing the pressure relief function. The outside of the insert itself engages with a sealing surface in the cavity in the valve body to provide the check valve function.
Abstract:
A nut-plate riveter which includes multiple pistons which assist in creating a pulling force. The nut-plate riveter provides that spent mandrels are pulled through the tool, thereby avoiding problems in the field. The nut-plate riveter includes a handle and a plurality of pistons disposed in the handle. Cavities are proximate the pistons for pressurizing the pistons, and air supply passages are in communication with the cavities for supplying air to the cavities to pressurize the pistons. A piston rod is engaged with at least one of the pistons, and the piston rod has a longitudinal bore therethrough which is configured to receive a spent mandrel. A deflector fitting may be disposed at an end of the nut-plate riveter.