For the purpose of providing a valve arrangement for controlling pneumatic drives with protection against a sudden automatic change in the initial switching position without an input signal in the event of a fault in a resetting device of a pilot stage and, for this situation, effective fault identification by purely pneumatic means, said valve arrangement comprises a first and a second working connection (1; 2), which can be connected to a drive, and a first and a second electropneumatically pilot-controlled directional valve, in which valve arrangement one or both directional valves is or are arranged upstream of the working connections (1; 2) for the purpose of influencing and venting said working connections, wherein the pilot stages of both directional valves are of automatically resetting design and the second directional valve is designed for alternately assuming an inoperative position and a switching position and the pilot stage of the first directional valve has an external control connection (8; 8) which can be influenced by means of the second directional valve in its switching position and can be vented by means of said second directional valve in its inoperative position, wherein the second directional valve has, as a resetting device for the main stage (14), an air spring (19) which can be influenced and can be vented externally by means of the first directional valve, and a change in state between influencing or venting of the air spring (19) after the first directional valve assumes a switching position takes place only depending on the change in the switching state of the first directional valve, and a change in state between influencing or venting at one working connection (1; 2) after previous influencing or venting which took place with the second directional valve assuming the switching position takes place only depending on the second directional valve assuming the inoperative position.

For the purpose of providing a valve arrangement for controlling pneumatic drives with protection against a sudden automatic change in the initial switching position without an input signal in the event of a fault in a resetting device of a pilot stage and, for this situation, effective fault identification by purely pneumatic means, said valve arrangement comprises a first and a second working connection (1; 2), which can be connected to a drive, and a first and a second electropneumatically pilot-controlled directional valve, in which valve arrangement one or both directional valves is or are arranged upstream of the working connections (1; 2) for the purpose of influencing and venting said working connections, wherein the pilot stages of both directional valves are of automatically resetting design and the second directional valve is designed for alternately assuming an inoperative position and a switching position and the pilot stage of the first directional valve has an external control connection (8; 8) which can be influenced by means of the second directional valve in its switching position and can be vented by means of said second directional valve in its inoperative position, wherein the second directional valve has, as a resetting device for the main stage (14), an air spring (19) which can be influenced and can be vented externally by means of the first directional valve, and a change in state between influencing or venting of the air spring (19) after the first directional valve assumes a switching position takes place only depending on the change in the switching state of the first directional valve, and a change in state between influencing or venting at one working connection (1; 2) after previous influencing or venting which took place with the second directional valve assuming the switching position takes place only depending on the second directional valve assuming the inoperative position.

A flow rate controller and a drive device are provided with a first flow passage connected between an operation switching valve and an air cylinder, and that supplies air to and discharges air from a cylinder chamber of the air cylinder; a first flow rate adjustment part provided in the first flow passage; a second flow passage adjacent to the first flow passage; a pilot check valve provided at a point along the second flow passage; a second flow rate adjustment part connected in series to the pilot check valve at a point along the second flow passage; a pilot air flow passage, one end of which communicates with the operation switching valve and the other end of which is connected to a pilot port of the pilot check valve; and a third flow rate adjustment part provided in the pilot air flow passage.

A flow rate controller and a drive device are provided with a first flow passage connected between an operation switching valve and an air cylinder, and that supplies air to and discharges air from a cylinder chamber of the air cylinder; a first flow rate adjustment part provided in the first flow passage; a second flow passage adjacent to the first flow passage; a pilot check valve provided at a point along the second flow passage; a second flow rate adjustment part connected in series to the pilot check valve at a point along the second flow passage; a pilot air flow passage, one end of which communicates with the operation switching valve and the other end of which is connected to a pilot port of the pilot check valve; and a third flow rate adjustment part provided in the pilot air flow passage.

[Object] To make it possible to detect, with a single pressure sensor, a malfunction of two solenoid valves for switching flow paths and to quickly and reliably exhaust residual pressure in an air device through a solenoid valve.

[Solution] A residual pressure exhaust air circuit 1 includes: a main flow path 9 through which air from an air source 2 is supplied to an air cylinder 100; an exhaust flow path 10 through which air in the air cylinder 100 is exhausted; a first sensor 8 for detecting a malfunction of solenoid valves 12, 13; a detection flow path 11 through which air from the air source 2 is supplied to the first sensor 8; and the two solenoid valves 12, 13 that switch communication states among the main flow path 9, the exhaust flow path 10, and the detection flow path 11. The two solenoid valves 12, 13 are formed of two-position valves having first positions 12a, 13a at the time of OFF and second positions 12b, 13b at the time of ON and are synchronously ON/OFF controlled. When the two solenoid valves 12, 13 do not operate in synchronization with each other, the air from the air source 2 is supplied to the first sensor 8 to detect a malfunction of the two solenoid valves 12, 13, and at the same time, the air in the air cylinder 100 is exhausted through the solenoid valve 12, 13.

A compressed air supply device having a simple structure capable of supplying compressed air from an outside to pneumatic equipment incorporated into a moving device. This compressed air supply device includes: an air supply head provided with an opposite surface opposing to a connection surface; an air supply rod arranged in the air supply head so as to be reciprocable between a projecting position where a projecting surface protrudes from the opposite surface and a retraction position where the projecting surface is retracted from the projecting position; and an on-off valve blocking communication between a compressed air supply source and an air guide path when the projecting surface is away from the connection surface and causing the compressed air supply source and an air inflow path to communicate with each other via the air guide path when the connection surface abuts on the projecting surface.

A compressed air supply device having a simple structure capable of supplying compressed air from an outside to pneumatic equipment incorporated into a moving device. This compressed air supply device includes: an air supply head provided with an opposite surface opposing to a connection surface; an air supply rod arranged in the air supply head so as to be reciprocable between a projecting position where a projecting surface protrudes from the opposite surface and a retraction position where the projecting surface is retracted from the projecting position; and an on-off valve blocking communication between a compressed air supply source and an air guide path when the projecting surface is away from the connection surface and causing the compressed air supply source and an air inflow path to communicate with each other via the air guide path when the connection surface abuts on the projecting surface.

A fluid control valve includes a first flow path and a second flow path that connect a first port and a second port in parallel. The first flow path includes an opening and closing valve mechanism that temporarily opens the first flow path. The second flow path includes a throttle valve mechanism that restrictedly opens the second flow path. The opening and closing valve mechanism includes an opening and closing valve portion including an opening and closing valve seat and an opening and closing valve body, a valve opening force generator, and a delay valve closing mechanism that closes the opening and closing valve body after a delay time has elapsed. The throttle valve mechanism includes a throttle valve portion. The opening area of the opening and closing valve portion is larger than the opening area of the throttle valve portion.

A vehicle seat includes a bladder as an actuator; a pump that is operated to supply air to the bladder; a switch that is operated to operate the pump; and a switching valve that is disposed in an air supply/discharge passage for the air for the bladder, the switching valve being configured to connect the air supply/discharge passage to a discharge port of the pump when the air is supplied to the bladder, and to connect the air supply/discharge passage to an exhaust port when the air is discharged from the bladder. The switching valve is incorporated in the switch, and is configured to receive an operating force applied to the switch, and to supply and discharge the air to and from the bladder in accordance with an operation of the switch.

A vehicle seat includes a bladder as an actuator; a pump that is operated to supply air to the bladder; a switch that is operated to operate the pump; and a switching valve that is disposed in an air supply/discharge passage for the air for the bladder, the switching valve being configured to connect the air supply/discharge passage to a discharge port of the pump when the air is supplied to the bladder, and to connect the air supply/discharge passage to an exhaust port when the air is discharged from the bladder. The switching valve is incorporated in the switch, and is configured to receive an operating force applied to the switch, and to supply and discharge the air to and from the bladder in accordance with an operation of the switch.