Abstract:
The object of the present invention is to provide a three-way valve reduced in the number of component parts and man-hours for assembling the component parts. A pressure chamber of a piston for urging a first main valve in a valve-closing direction by a spring, and a pressure chamber of a piston for urging a second main valve in a valve-opening direction against the urging force of a spring are connected to a medium-pressure port B via a pilot valve and a pressure passage. When the pilot valve is open, the pressure in the pressure chambers into which high-pressure fluid is introduced from a high-pressure port A via an orifice is permitted to escape to the medium-pressure port B, whereby the piston is pushed upward by the high pressure to open the first main valve, and a plug is urged by the spring to close the second main valve. When the pilot valve is closed, the pressure in the pressure chambers becomes high, so that the piston is pushed downward by the spring to close the first main valve, and the piston is pushed downward by the high pressure to open the second main valve. Since the pilot valve is formed by a two-way solenoid valve, and the pressure passage is formed within a body, it is possible to reduce the number of component parts.
Abstract:
A valve for controlling flowing media, in particular suction air used in connection with suction heads or the like, in which closing diaphragms (17, 18) made from elastically deformable material are disposed within a valve housing (10) and are subjected to the action of compressed air via actuating lines (14, 15) in the closing or blocking direction, such that when each diaphragm (17, 18) moves into an open position, a subatmospheric pressure is generated on the side ling opposite the closing side.
Abstract:
An electrohydraulic valve pilot stage for controlling differential pressure is disclosed. The electrohydraulic valve pilot stage has a housing for protecting the valve; a first and second inlet capable of connection to fluid supplies; a first nozzle and a second nozzle fluidly connected to the inlets; a baseplate attached to the housing and the nozzles; a restraining member attached to the baseplate at a position between the first nozzle and the second nozzle; a pivot pin; a flapper restrained by the restraining member and having a first end and a second end, the flapper pivotably mounted on the pivot pin; and a null adjust pin mounted in a pivot pin contact capable position for adjusting the position of the ends of the flapper relative to the nozzles.
Abstract:
The present invention provides a construction machine with a structure of pilot pipe comprising detection ports for detecting pilot pressure in a body of a switching valve, so that the number of pipe connecting positions and pipe assembly parts such as joints and the like can be decreased and arrangement of the pipe can be simplified.
Abstract:
It is an object of the present invention to provide a control valve which can reduce the number of external lines connected to a hydraulic remote control valve. A control valve 1 for controlling hydraulic cylinders 2,2′ is provided, in one 26 of spool covers, with fluid passages 27,27′, a shuttle valve 28 for selecting higher one of pilot pressures to be transmitted to these fluid passages 27,27′, and a fluid passage 29 for transmitting the pressure selected by the shuttle valve 28. The fluid passages 27,27′ are in communication with pressure fluid ports 25,25′ as connection ports for pilot lines 24a,24c. The control valve 1 is also provided, in the other spool cover 32, with fluid passages 33,33′, a shuttle valve 34 for selecting higher one of pilot pressures to be transmitted to these fluid passages 33,33′, and a fluid passage 35 for transmitting the pressure selected by the shuttle valve 34. The fluid passages 33,33′ are in communication with pressure fluid ports 31,31′ as connection ports for pilot lines 24b,24d.
Abstract:
A working cylinder (A) having at least one working chamber (6, 7) defined by the cylinder barrel (1), at least one of the end sections (2, 3) and a piston (4), at least one supply port (9a, 9b) and a exhaust port (12a, 12b) for the working medium. The exhaust port (12a, 12b) has a valve (13a, 13b) that may be regulated by the pressure of the working medium, which is applied at the supply port (9a, 9b) in order to obtain a smaller dimension of at least the valve and to better utilize the already existing space, specifically within the cylinder, and to better and more efficiently adjust the output capacity of the individual elements. A valve (V), particularly a switch valve (W) of a rocker valve design has therefore at least one inlet (16) and at least one outlet (17a, 17b) for the working medium, as wells as at least one control port (18). The cylinder is characterized by a discharge channel (19, 19a; 38a, 38b) for the working medium, originating from a location between the valve element (15; 31, 33) of the valve and at least one outlet (17a, 17b), whereby this discharge channel has a discharge or exhaust valve (20, 22; 36a, 36b), which may be regulated electrically or by the pressure applied to the control port. The pressure-actuated working unit comprises a pneumatic working cylinder (A) with exhaust valves (27a, 27b), a valve (V, W) and exhaust control valves (24a, 24b; 30) as well as only one pressure line (29a, 29b) to each working chamber (6, 7) in the cylinder (A).
Abstract:
In a check valve assembly and a valve assembly employing such a check valve assembly, a topping piston may be taken into contact with a main poppet to raise the main poppet from its seat. The main poppet is designed without significant area difference from the valve seat and the topping piston is actuated through a pilot valve, so that the process of raising the main poppet from the valve seat is controllable.
Abstract:
A valve assembly for actuation of a user and a method for actuation of the valve assembly, wherein a supply throttle device and a drain throttle device may be actuated independent of each other, is disclosed. In the case of single-action users, the drain throttle device is actuated such that the open cross-section of the drain throttle is maximum upon attaining the desired volumetric flow of hydraulic oil, so that the energy losses in the drain conduit are reduced to minimum.
Abstract:
A three-way or multi-way valve is provided, which is built up of a plurality of two-way valves, each of which has a high pressure connection and a low pressure connection which are separated from each other by means of a valve seat with which a closure element co-operates, the two-way valves being arranged to be operated in pairs or in groups by means of a control pressure fluid by way of a control pressure line opening into a pressure chamber, and one of the two-way valves of each group being arranged in a connection between a pressure source and a load, and another two-way valve of the same groups being arranged in a connection between the load and a pressure sink. With a valve of this type, it is desired to obtain improved closing behavior with simple construction. For this purpose, at least one of the connections, especially the high pressure connection, of at least one valve of each group communicates with the control pressure line by way of a throttle channel.
Abstract:
A two stage valve assembly responsive to signals from a control system for supplying pressurized fluid to two load lines. The first stage includes a motor that directs pressurized fluid from a jet pipe toward a receiver assembly having two receiver ports and a bleedoff area disposed between and separating the receiver ports. The second stage assembly includes two spool/sleeve assemblies that control the flow of pressurized fluid to and from the two load lines. A drain line from the receiver assembly includes a pressure relief valve, which insures that both spool/sleeve assemblies will be servo-controlled at all times. Cartridges may be inserted in the spool/sleeve assemblies to linearize the relationship between input current from the control system and the output force of an unequal area actuator connected to the load lines.