Abstract:
A valve assembly includes a valve housing defining a service passage, a first bore in fluid communication with the service passage, a first passage, a second bore in communication with the service passage and a second passage. The first bore has an inlet portion, a first service portion in communication with the service passage, and a first load holding portion. The first passage is in communication with the first load holding portion and the service passage. The second bore has a return portion, a second service portion in fluid communication with the first service passage, and a second load holding portion. The second passage is in selective communication with the second load holding portion of the second bore and the return passage. A valve is disposed in the second passage. The valve allows fluid to flow only in a direction from the second load holding portion to the return passage.
Abstract:
The present invention describes, generally, a method and system for controlling the dynamics of an actuatable load functioning or operable within a servo or servo-type system, wherein the dynamics of the load are controlled by way of a unique asymmetric pressure control valve configured to provide intrinsic pressure regulation. The asymmetric pressure control valve, which may be referred to as a dynamic pressure regulator because of its capabilities, utilizes different sized free floating spools that are physically independent of one another and freely supported in interior cavities of respective corresponding different sized valving components that make up the valve body to regulate the pressures acting within the overall system between the control or pilot pressure and the load or load pressure. The dual spools of the pressure control valve, although physically independent of one another, function in cooperation with one another in an attempt to maintain a state of equilibrium in the system, namely to keep pressure acting on or within the actuator (the load pressure), or the feedback pressure corresponding to the load pressure, the same as the control or pilot pressure. Moreover, pressure regulation and control is intrinsic to the asymmetric pressure control valve because of the configuration and function of the dual spools and the feedback system acting on the spools, thus eliminating the need for electronically or mechanically user controlled systems.
Abstract:
A lift axle control module is disclosed that is simpler than prior art lift axle control systems, and does not require cycling the input pressure to the regulator. The module includes a housing fluidly connected to a first pressurized air supply and having one chamber with a load bladder port, a second chamber with a lift bladder port, and a common vent port. A pilot pressure is selectively provided for switching the module between the retracted and deployed modes. When the control module is set to the retracted mode, the lift bladders are pressurized to the system pressure, and the load bladders are vented. When the control module is set to the deployed mode, the lift bladders are vented and the load bladders are inflated and maintained at the regulated pressure.
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:
The present invention is a pressure feedback circuit for use with a vacuum pressure control circuit. The pressure feedback circuit detects the occurrence of, and controls the generation of vacuum pressure under, External Override Conditions (“EOCs”). During EOCs, which typically include emergency stop conditions or loss of electrical power to the vacuum pressure circuit, the pressure feedback circuit senses the condition of the output vacuum pressure port and supplies feedback to the vacuum pressure control circuit thereby maintaining the last output state of the vacuum pressure control circuit.
Abstract:
An on/off valve (O/OV) and directional valves (DV1, DV2) are packaged with a switching valve system (10) in a housing assembly (156, 157, 158, 160). The on/off valve (O/OV) is operated by a control handle (154) that is located at one end of the housing assembly (156, 157, 158, 160). The direction control valves (DV1, DV2) are operated by a handle (141) located at the opposite end of the housing assembly (156, 157, 158, 160). The control handles (154, 141) operate to position cams (152, 136, 138) which function to help position valve plugs. In a second embodiment, the handle (141) and cams (136, 138) for controlling the directional valves (DV1, DV2) are replaced by a solenoid valve system (SV2) . A second solenoid valve (SV1) is added to the control system for the off/on valve (O/OV). The solenoid valve (SV1, SV2) allow for a remote positioning of the controls for the off/on and directional valves (O/OV, DV1, DV2). The handles and cams (141, 154, 136, 138, 152) provide for a compact positioning of the controls at one location requiring utilization of a single compact valve housing assembly (156, 157, 158, 160).
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:
A process gas supply system at the gas supply point includes an automated means for evacuating gas in a process line fed by the process gas supply system when an abnormal event occurs. The process gas supply system of this invention eliminates the need for any special valves or piping at the point of use of the process gas as well as the need for a return line from the point of use to the process gas supply system to purge the process line. A process gas is contained in a cylinder under pressure. The cylinder is coupled to a process line by the process gas supply system. The process gas supply system includes a gas flow controller and an automatic evacuation system. The gas flow controller controls the supply of the process gas from the cylinder to the process line. In an abnormal event, process gas flow from the cylinder is blocked by the gas flow controller and the automatic evacuation system evacuates the process gas not only from the gas flow controller, but also from the process line.
Abstract:
A process gas supply system at the gas supply point includes an automated means for evacuating gas in a process line fed by the process gas supply system when an abnormal event occurs. The process gas supply system of this invention eliminates the need for any special valves or piping at the point of use of the process gas as well as the need for a return line from the point of use to the process gas supply system to purge the process line. A process gas is contained in a cylinder under pressure. The cylinder is coupled to a process line by the process gas supply system. The process gas supply system includes a gas flow controller and an automatic evacuation system. The gas flow controller controls the supply of the process gas from the cylinder to the process line. In an abnormal event, process gas flow from the cylinder is blocked by the gas flow controller and the automatic evacuation system evacuates the process gas not only from the gas flow controller, but also from the process line.
Abstract:
A supply circuit for a hydraulic fluid system has at least one pressure generation device, at least one connecting valve, a main line and a safety deactivation unit. The supply circuit permits a hydraulic fluid to be fed in such a way that, in all operating states, occurrence of pressure surges in the system is prevented. The connecting valve is designed as a slide valve with three control edges for regulating filling, operation and testing functions. A plate valve, in fluid communication with the slide control valve, is designed as an outflow amplifier and fulfills the safety related tasks.