JP6741567B2 - Air supply system for trailer and air supply system for vehicle - Google Patents

Description

The present invention relates to a trailer air supply system and a vehicle air supply system for supplying air to a brake mechanism of a trailer.

A pneumatic brake system using air compressed by a compressor is used as a brake system for a freight vehicle including a tractor (towing vehicle) and a trailer (towed vehicle). The pneumatic brake system consists of a brake chamber that operates the brakes of the tractor, an air supply system for the tractor that controls the supply of air to the brake chambers, a brake chamber that operates the brakes of the trailer, and an air supply to the brake chambers. A trailer air supply system for controlling the supply.

The compressor is mounted on the tractor, and the tractor air supply system is connected to the compressor. The trailer air supply system is connected to the tractor air supply system via a connection path (trailer control pipe). The air compressed by the compressor is supplied to the trailer air supply system via the tractor air supply system (see, for example, Patent Document 1).

By the way, the air compressed by the compressor contains many impurities such as water, oil, and dust. If this compressed air is supplied to the pneumatic brake system as it is, it will cause malfunction of each device constituting the pneumatic brake system. For this reason, an air conditioning apparatus such as an air dryer is provided in the tractor air supply system. The air purified by the air conditioning apparatus is supplied to the tractor air supply system and the trailer air supply system.

Special table 2001-511087 gazette

However, the path length from the air dryer to the brake chamber of the trailer is longer than the path length from the air dryer mounted on the tractor to the brake chamber of the tractor. In addition, many devices are provided in the middle of the flow path. Therefore, impurities are more likely to be mixed into the air flowing through the path from the air dryer to the brake chamber of the trailer, compared to the tractor side. Therefore, it is desired to supply the trailer air supply system with air having the same degree of cleanliness as the tractor air supply system.

The present invention has been made in view of such circumstances, and an object thereof is to provide an air supply system for a trailer and an air supply system for a vehicle that can improve the cleanliness of air used for a brake in a trailer. Especially.

A trailer air pressure system for solving the above-mentioned problems is a trailer air supply system connected to a tractor air supply system via a connecting portion, and a distributor for distributing air to a brake mechanism provided on a wheel of the trailer. And an air conditioning section that is provided between the connection section and the distribution section and cleans the air supplied from the tractor air supply system.

According to the above configuration, since the trailer air supply system includes the air conditioning section between the connection section that is connected to the tractor air supply system and the distribution section that distributes air to the brake mechanism of the trailer, cleaning is performed. The generated air can be distributed to each brake mechanism. As a result, the cleanliness of the air used for the brake in the trailer can be increased. Therefore, malfunction of the brake mechanism or the like due to impurities contained in the air can be suppressed.

In the trailer pneumatic system, when the air conditioning section is regenerated, a discharge valve that discharges a fluid containing impurities generated by the regeneration, a control valve that controls the supply of air to the air conditioning section, and the discharge Valve and a governor that outputs an air pressure signal to the control valve, the control valve shuts off the supply of air to the air conditioning section when the air pressure signal is input, and the discharge valve is the It is preferable to discharge the fluid containing the impurities when the pneumatic signal is input.

According to the above configuration, when the air pressure signal is supplied from the governor, the control valve shuts off the supply of air to the air conditioning section, and the discharge valve discharges the fluid containing impurities generated by the regeneration. As described above, when the air conditioning section is regenerated, the control valve provided on the upstream side of the air conditioning section shuts off the air supply to the air conditioning section, so that the air supplied from the tractor air supply system is supplied. However, it is possible to prevent wasteful discharge through the discharge valve. Therefore, useless consumption of the air supplied from the tractor air supply system can be suppressed.

In the trailer pneumatic system, the distribution unit distributes air to the brake mechanism when air is supplied as an air pressure signal, and is connected to the connection unit and supplies an air pressure signal to the distribution unit. And a second supply path that is connected to the connection section and that supplies air to the brake mechanism via the distribution section, and the air conditioning section includes only the second supply path. Is preferably provided in the.

According to the above configuration, the air conditioning section is provided only in the second supply path that supplies air to the brake mechanism. On the other hand, since the air conditioning section is not provided in the first supply path for supplying the air pressure signal to the distribution section, the air conditioning section delays the supply of air or lowers the pressure in the first supply path. Never. Therefore, it is possible to improve the responsiveness from when the air pressure signal is sent to the first supply path to when the air is distributed to the brake mechanism via the distributor.

In the trailer pneumatic system, it is preferable that the flow path provided with the air conditioning section is connected in series to the flow path provided with the air conditioning section for the tractor via the connection section.

According to the above configuration, the air conditioning section for the trailer is provided in series with the air conditioning section for the tractor. That is, the air purified by the air conditioning section for the tractor is sent to the trailer air supply system and further purified by the air conditioning section for the trailer. Therefore, the cleanliness of the air sent to the trailer can be further enhanced.

In the trailer pneumatic system, it is preferable that the flow path provided with the air conditioning section is connected in parallel to the flow path provided with the air conditioning section for the tractor via the connection section.

According to the above configuration, the air conditioning section for the trailer is provided in parallel with the air conditioning section for the tractor. According to this, as compared with the case where the air conditioning section for the tractor and the air conditioning section for the trailer are provided in series, the amount of air passing through the air conditioning section for the tractor decreases, so The amount of impurities captured by the air conditioning section is also reduced. Therefore, the frequency of regenerating the air conditioning unit for the tractor can be reduced, and the amount of air consumed by the regeneration can be reduced.

According to the present invention, the cleanliness of the air used for a brake in a trailer can be raised.

The figure which shows schematic structure of the brake system of the vehicle to which an air supply system for trailers is applied about one embodiment of an air supply system for trailers. The figure which shows the cross section of the control valve of the air supply system for trailers in the same embodiment, (a) is a connection position, (b) is a figure which shows a cutoff position. FIG. 3 is a pneumatic circuit diagram showing a part of the trailer air supply system of the same embodiment, when air conditioning is performed. FIG. 6 is a pneumatic circuit diagram showing a part of the trailer air supply system of the same embodiment when the filter unit is regenerated. The pneumatic circuit diagram which shows a part of trailer air supply system of a modification.

Hereinafter, an embodiment that embodies a trailer air supply system will be described.
With reference to FIG. 1, a schematic configuration of a pneumatic brake system of a truck as a freight vehicle will be described. The truck has a tractor (a tow vehicle) and a trailer (a towed vehicle) towed by the tractor. The pneumatic brake system 10 has a tractor air supply system 11 mounted on a tractor and a trailer air supply system 12 mounted on a trailer.

The tractor air supply system 11 is connected to the compressor 15. The compressor 15 is driven by the power of a truck engine (not shown), compresses air, and supplies the compressed air to the tractor air supply system 11. An air dryer 17 is provided in the tractor air supply passage 16 connected to the compressor 15.

The air dryer 17 includes a filter section 20 as an air conditioning section. The filter unit 20 has a drying filter that captures the moisture contained in the air, and an oil capture filter that captures the oil and dust contained in the air. The air sent from the compressor 15 passes through the filter section 20, whereby impurities are captured and the air is cleaned. The air thus cleaned is sent from the air dryer 17 to the tank 18. Hereinafter, the direction of the air when the air sent from the compressor 15 is passed through the filter unit 20 for cleaning is referred to as the “conditioning direction”.

Further, the air dryer 17 includes a governor 21 as a pressure regulator. When the pressure between the governor 21 and the tank 18 in the tractor air supply passage 16 becomes equal to or higher than the upper limit value, the governor 21 supplies the compressor 15 with air of a predetermined pressure as an unload signal. When the unload signal is input, the compressor 15 performs no-load operation without compressing air. Further, the governor 21 also outputs an unload signal to the discharge valve 22 of the air dryer 17. The discharge valve 22 opens when the unload signal is input, and closes when the unload signal is not input. When the discharge valve 22 opens, the air in the air dryer 17 flows in the direction opposite to the tempering direction, which is the flow of air when cleaning the air. The flow of air at this time is called the "reproduction direction". As a result, the impurities captured by the filter unit 20 are discharged as drain with the air flowing in the regeneration direction from the discharge valve 22, and the filter unit 20 is regenerated (cleaned). Further, when the filter unit 20 is regenerated in this way, the compressor 15 performs no-load operation by inputting the unload signal, so that the compressed air is not wasted.

Then, when the pressure in the tank 18 becomes less than the upper limit value or becomes equal to or less than the lower limit value set to a value lower than the upper limit value, the governor 21 stops the supply of the unload signal. As a result, the compressor 15 performs load operation in which air is compressed. Further, since the discharge valve 22 is closed by stopping the supply of the unload signal, the air compressed by the compressor 15 flows in the air dryer 17 in the tempering direction.

The air stored in the tank 18 passes through a protection valve (protection valve) 19 and an air supply passage 31 for the front wheels of the tractor, an air supply passage 32 for the rear wheels, and an air supply passage 33 for the parking brake. Will be distributed to. A brake valve 34 operated by a driver is provided in each of the air supply flow paths 31 and 32. In response to the operation of the brake valve 34, air is supplied via the control valve 35 to the brake chamber 40 as a brake mechanism provided on the front wheels and the brake chamber 41 provided on the rear wheels, and the service brake is operated. Further, the brake chamber 41 for the rear wheels is provided with a structure for operating the parking brake, such as a spring. An air supply passage 33 for a parking brake is connected to these brake chambers 41. The parking brake is released when air is supplied to the brake chamber 41 through the air supply passage 33, and the parking brake is operated when air is discharged from the brake chamber 41.

A signal path 45 is connected to the brake valve 34. Further, a supply path 46 is connected to the protection valve 19. The end of the signal path 45 opposite to the end connected to the brake valve 34 and the end of the supply path 46 opposite to the end connected to the protection valve 19 are connected to a hose coupling. Etc. are provided respectively. The signal path 45 on the tractor side is connected to a signal path 48 on the trailer side as a first supply path via a connecting portion 47. A trailer-side supply passage 49 as a second supply passage is connected to the tractor-side supply passage 46 via a connecting portion 47.

The signal input port 50P of the relay valve 50 is connected to the trailer-side signal path 48. When the driver operates the brake valve 34 to supply air to the signal path 45 of the tractor, air is supplied to the signal input port 50P of the relay valve 50 via the signal path 48 of the trailer. The relay valve 50 allows the air supplied from the tractor side via the supply path 49 to the brake chamber 41 as a brake mechanism provided on the wheel of the trailer according to the presence or absence of the input of the air pressure signal to the signal input port 50P. Supply. The brake chamber 41 of the trailer is a chamber that operates only the service brake. Further, the relay valve 50 automatically activates the emergency brake when the tractor and the trailer are separated, the brake circuit fails, and the like.

A control valve 51 is provided in the supply path 49 on the trailer side. The control valve 51 is configured to be able to change its position between a connection position that connects the tractor air supply system 11 and the brake chamber 41 side by communicating the supply passage 49 and a cutoff position that shuts off the supply passage 49. .. Further, the control valve 51 operates by inputting air having a predetermined pressure as an air pressure signal. The control valve 51, when an air pressure signal is input to the signal input port 51P, is in a shutoff position that shuts off the supply passage 49, and is in a connection position that communicates the supply passage 49 when no air pressure signal is input.

An air dryer 70 is provided downstream of the control valve 51 in the supply path 49. The air dryer 70 has the same configuration as the air dryer 17 provided in the tractor air supply system 11, and has a filter unit 20 as an air conditioning unit, a discharge valve 22, and a governor 21. The air dryer 70 purifies the air by allowing the air supplied from the tank 18 via the control valve 51 to pass through the filter unit 20. Further, the air dryer 70 is different from the air dryer 17 of the tractor in that the governor 21 is connected to the signal input port 51P of the control valve 51 and is not connected to the compressor 15. The governor 21 of the air dryer 70 sends an air pressure signal to the discharge valve 22 and the control valve 51 when the air pressure between the relay valve 50 and the air dryer 70 is equal to or higher than the upper limit value Pmax. Further, the governor 21 stops the supply of the air pressure signal when the air pressure between the relay valve 50 and the air dryer 70 is less than the upper limit value Pmax or less than or equal to the lower limit value Pmin lower than the upper limit value Pmax.

A relay valve 50 is provided downstream of the air dryer 70 in the supply path 49. The input port of the relay valve 50 is connected to the supply path 49, and the signal input port 50P is connected to the signal path 48 as described above. Further, the relay valve 50 has an input/output port that allows bidirectional air flow, and the tank 71 is connected to this input/output port. The air purified by the air dryer 70 is stored in the tank 71. Further, the output port of the relay valve 50 is connected to the chamber connection path 42 that communicates with the brake chamber 41. The air stored in the tank 71 is supplied to the chamber connection path 42 via the relay valve 50. A control valve 72 that controls the supply of air to the brake chamber 41 is provided in the middle of the chamber connection path 42.

The configuration of the control valve 51 will be described with reference to FIG. The control valve 51 includes a first flow path forming member 52 and a second flow path forming member 53. The tip of the first flow path forming member 52 is fitted into the fitting hole 62 of the second flow path forming member 53. The first flow path forming member 52 has a signal input port 51P connected to the governor 21. Further, the first flow path forming member 52 has a hole 54 that opens at the end face opposite to the signal input port 51P, and the hole 54 communicates with the signal input port 51P via the communication hole 55. doing. A valve element 61 is slidably provided in the hole 54.

The second flow path forming member 53 has an input port 56 connected to the supply path 49, and an inlet flow path 57 extending from the input port 56 in parallel with the hole 54 of the first flow path forming member 52. doing. A valve seat 58 is provided at an end portion of the inlet passage 57 opposite to the input port 56. Further, the second flow path forming member 53 has an output port 59 connected to the air dryer 70 side and an outlet flow path 60 communicating with the inlet flow path 57 and extending in a direction orthogonal to the inlet flow path 57. Has been formed.

As shown in FIG. 2A, when the pressure at the signal input port 51P is less than the predetermined pressure, the valve body 61 is pressed toward the signal input port 51P by the air pressure at the input port 56 side. As a result, the valve body 61 separates from the valve seat 58, and the inlet channel 57 and the outlet channel 60 are connected to each other. As a result, the air supplied from the tractor side through the supply path 49 passes through the control valve 51 from the input port 56 and is sent from the output port 59 to the air dryer 70 side.

As shown in FIG. 2B, when the pressure of the signal input port 51P is equal to or higher than a predetermined pressure, the valve body 61 is pushed to the input port 56 side and abuts on the valve seat 58, so that the inlet passage 57 and The cutoff position is set to cut off the connection of the outlet channel 60. As a result, the air supplied from the tractor side via the supply path 49 is not sent to the air dryer 70 side.

Next, the configuration of the air dryer 70 will be described in detail with reference to FIGS. 3 and 4. A supply path 49 is connected to the input port P1 of the air dryer 70. An in-dryer supply path 49A is provided between the input port P1 and the output port P2 of the air dryer 70. A filter unit 20 having an oil capturing filter 20A and a drying filter 20B is provided in the middle of the in-dryer supply path 49A. Although the oil trapping filter 20A is provided upstream of the drying filter 20B in FIGS. 3 and 4, the oil trapping filter 20A may be provided downstream of the drying filter 20B. A check valve 75 is provided downstream of the filter section 20 in the in-dryer supply path 49A. The check valve 75 allows a flow of air from the filter unit 20 toward the output port P2 of the air dryer 70, and blocks a flow of air from the output port P2 toward the filter unit 20. To the upstream side and the downstream side of the check valve 75, one end portion and the other end portion of the detour having the orifice 80 are connected. Instead of the orifice 80, a control valve that opens and closes the bypass by an electric signal or a pneumatic signal may be provided.

Further, a discharge path 49B branching from the in-dryer supply path 49A is connected to the in-dryer supply path 49A. A discharge valve 22 is provided in the discharge path 49B. The discharge valve 22 is a valve controlled by air pressure, and a discharge port 76 is provided downstream thereof. The discharge valve 22 is configured to be capable of changing its position between a discharge position that discharges a drain that is a fluid containing impurities and air that has passed through the filter unit 20 and a cut-off position that blocks communication between the discharge passage 49B and the discharge port 76. Has been done.

The governor 21 is connected to the signal input port 22P of the discharge valve 22 via a signal supply path 78. The governor 21 supplies air having a predetermined pressure or higher to the signal input port 22P as an air pressure signal. The discharge valve 22 is in the discharge position when the air pressure signal is input, and is in the shut-off position when the air pressure signal is not input. In addition, the discharge valve 22 has a spring 22S that applies a biasing force to the shut-off position.

The governor 21 is connected to a signal supply path 77 that communicates with the signal input port 51P of the control valve 51 and a communication path 79 that connects to the downstream side of the check valve 75. The governor 21 also has an exhaust port 21E. The governor 21 supplies the air in the flow passage on the downstream side of the check valve 75 to the control valve 51 and the discharge valve 22 as an air pressure signal when the pressure on the downstream side of the check valve 75 becomes equal to or higher than the upper limit value Pmax. This is the signal supply position. Further, the governor 21 connects the signal supply paths 77, 78 and the exhaust port 21E when the pressure on the downstream side of the check valve 75 is less than the upper limit value Pmax or less than the lower limit value Pmin lower than the upper limit value Pmax. Exhaust position. The governor 21 is biased by the spring 21S so as to be in the exhaust position.

Next, the operation of the trailer air supply system 12 will be described with reference to FIGS. 3 and 4.
The governor 21 of the trailer air supply system 12 exhausts air when the pressure in the communication passage 79, in other words, the pressure on the downstream side of the air dryer 70 is less than the upper limit Pmax or less than the lower limit Pmin smaller than the upper limit Pmax. Maintained in position. As a result, no air pressure signal is input to the signal input port 22P of the discharge valve 22, so the discharge valve 22 is maintained in the shut-off position. Further, since no air pressure signal is input to the signal input port 51P of the control valve 51, the control valve 51 is at the connection position that connects the supply passage 49 and the in-dryer supply passage 49A. As a result, the air supplied from the tractor air supply system 11 passes through the filter section 20 of the air dryer 70 in the tempering direction. In the filter section 20, the oil content in the air is captured by the oil content capturing filter 20A, and the water content in the air is captured by the drying filter 20B. The air thus cleaned is sent from the air dryer 70 to the tank 71 via the relay valve 50 (see FIG. 2). The air stored in the tank 71 is supplied to the brake chamber 41 by operating the brake valve 34.

As shown in FIG. 4, the governor 21 is in the signal supply position when the pressure in the communication passage 79, in other words, the pressure on the downstream side of the air dryer 70 becomes equal to or higher than the upper limit value Pmax. As a result, air is supplied from the communication passage 79 to the signal supply passages 77 and 78 as an air pressure signal. When an air pressure signal is input to the signal input port 22P of the discharge valve 22, the discharge valve 22 is at the discharge position. Further, since the pneumatic signal is input to the discharge valve 22 and the pneumatic signal is input to the signal input port 51P of the control valve 51 at the same time, the control valve 51 is in the shut-off position. As a result, the air supply from the tractor air supply system 11 to the air dryer 70 is cut off. Further, since the discharge valve 22 is at the discharge position, the air between the tank 71 or the air dryer 70 and the tank 71 causes the filter portion 20 to flow in the direction opposite to the tempering direction via the orifice 80 provided in the bypass. It flows in the playback direction. As a result, the air flowing in the regeneration direction removes the impurities captured by the filter unit 20 when passing through the filter unit 20, and is sent to the discharge path 49B. The air containing impurities is discharged from the discharge port 76 via the discharge passage 49B and the discharge valve 22. The drain composed of water and oil may be recovered by a drain recovery unit (not shown) connected to the discharge port 76.

As described above, when the filter unit 20 is regenerated, the control valve 51 is in the shut-off position and the air supply to the in-drier supply path 49A is stopped, so that the air supplied from the tractor air supply system 11 is discharged from the air dryer 70. Not discharged via 22. Therefore, it is possible to prevent wasteful consumption of the air compressed by the compressor 15. Then, the load of the engine, which is the power source of the compressor 15, can be reduced by the amount by which the wasteful consumption of the compressed air is prevented, and the deterioration of the fuel efficiency of the engine can be suppressed.

When the air in the tank 71 is consumed due to the operation of the brake or the like, the pressure in the communication passage 79, in other words, the pressure on the downstream side of the air dryer 70 becomes less than the upper limit value Pmax or less than the lower limit value Pmin. As a result, the governor 21 shifts from the signal supply position to the cutoff position and stops the supply of the pneumatic signal. When the supply of the air pressure signal is stopped, the control valve 51 is in the connection position and the discharge valve 22 is in the cutoff position, and the air from the tractor air supply system 11 flows through the filter portion 20 in the tempering direction for cleaning. The generated air is sent to the tank 71.

As described above, according to the above embodiment, the following effects can be obtained.
(1) The trailer air supply system 12 includes an air dryer 70 having a filter portion 20 between a connection portion 47 connected to the tractor air supply system 11 and a relay valve 50 that distributes air to the brake chamber 41 of the trailer. As a result, the purified air can be distributed to each brake chamber 41. As a result, the cleanliness of the air used for the brake in the trailer can be increased. Therefore, malfunction of the brake chamber or the like due to impurities contained in the air can be suppressed.

(2) When the air pressure signal is supplied from the governor 21, the control valve 51 shuts off the air supply to the air dryer 70, and the discharge valve 22 discharges the fluid containing impurities generated by the regeneration. As described above, when the air dryer 70 is regenerated, the control valve 51 provided on the upstream side of the air dryer 70 shuts off the air supply to the air dryer 70, so that the air supplied from the tractor air supply system 11 is discharged from the exhaust valve 22. It is possible to prevent wasteful discharge via the. Therefore, useless consumption of the air supplied from the tractor air supply system 11 can be suppressed.

(3) The air dryer 70 is provided only in the supply path 49 that supplies air to the brake chamber 41. On the other hand, since the air dryer 70 is not provided in the signal path 48 for supplying the air pressure signal to the relay valve 50, the air dryer 70 does not delay the supply of air or reduce the pressure in the supply path 49. Therefore, it is possible to improve the responsiveness from when the air pressure signal is sent to the signal path 48 to when the air is distributed to the brake chamber 40 via the relay valve 50.

(4) The trailer air dryer 70 is provided in series with the tractor air dryer 17. That is, the air cleaned by the tractor air dryer 17 is sent to the trailer air supply system 12 and further cleaned by the trailer air dryer 70. Therefore, the cleanliness of the air sent to the trailer can be further enhanced.

(Other embodiments)
The above-described embodiment can also be implemented in the following modes.
In the above-described embodiment, the check valve 75 that blocks the flow of air from the downstream of the air dryer 70 toward the filter unit 20 is provided inside the air dryer 70. Alternatively, the check valve 75 may be provided outside the air dryer 70 and downstream of the air dryer 70.

In the above embodiment, the air dryer 70 is provided with the governor 21 that supplies an air pressure signal according to the pressure of the tank 71. The governor 21 may be provided separately from the air dryer 70.

In the above-described embodiment, the discharge valve 22 for discharging the fluid that has passed through the filter portion 20 in the regeneration direction is provided inside the air dryer 70. Alternatively, the discharge valve 22 may be provided separately from the air dryer 70 and connected downstream of the air dryer 70.

In the above-described embodiment, the air is supplied to the filter section 20 in the regenerating direction via the bypass route that bypasses the check valve 75. Instead of this, a tank that stores air for regenerating the filter unit 20 may be provided between the filter unit 20 and the check valve 75. Alternatively, the tank may not be provided, and the air stored in the conduit between the filter unit 20 and the check valve 75 may be supplied to the filter unit 20 at the time of regeneration to regenerate the filter unit 20.

In the above embodiment, the trailer is provided with the brake chamber 41 that operates only the service brake. However, the brake chamber 40 that operates only the service brake may be used. The point is that the brake mechanism is controlled by compressed air.

The configurations of the first flow passage forming member 52, the second flow passage forming member 53, and the valve body 61 included in the control valve 51 are the configurations of actuators other than the control valve 51 of the trailer air supply system 12, the brake chamber of the trailer. It can be changed as appropriate according to the air amount required for 41. The control valve 51 may have a configuration other than the configuration including the first flow path forming member 52, the second flow path forming member 53, and the valve body 61, and a biasing spring that biases the valve body 61 to the connection position. May be provided.

In the above embodiment, the discharge valve 22 is a valve that operates according to the unload signal that is the air pressure signal. Instead of this, the discharge valve 22 may be an electromagnetic valve that operates by an electric signal. Further, in the above-described embodiment, the control valve 51 is a valve that operates by an air pressure signal. Instead of this, the control valve 51 may be an electromagnetic valve that operates by an electric signal. When the discharge valve 22 and the control valve 51 are electromagnetic valves, the governor 21 that outputs an air pressure signal to them can be omitted.

In the above embodiment, the air dryer 70 is provided only on the supply path 49. Instead of this, the signal path 48 may be provided in addition to the supply path 49. Alternatively, when the supply path 49 and the signal path 48 are branched from one flow path, the air dryer 70 may be provided on the upstream side of the branch point.

In the above embodiment, the governor 21 is configured to be controlled by air pressure. Instead of this, the governor 21 may be configured to be electrically controlled. For example, as shown in FIG. 5, the governor 21 may be an electromagnetic valve controlled by the brake control device 90 or the like. The governor 21 may be in the signal supply position in the energized state in which an electric signal is input from the brake control device 90, and may be in the exhaust position in the non-energized state in which no electric signal is input. Alternatively, the governor 21 may be in the signal supply position in the non-energized state and in the exhaust position in the energized state. The brake control device 90 inputs a pressure detection signal from a pressure sensor (PU) 91 that detects the pressure in the communication passage 79 or the like. Then, the brake control device 90 outputs an electric signal to the governor 21 when the pressure in the communication passage 79 becomes equal to or higher than the upper limit value Pmax. In this way, not only the upper limit value Pmax but also various controls such as outputting an air pressure signal from the governor 21 when the pressure rising speed is equal to or higher than a predetermined speed can be performed.

In the above embodiment, the governor 21 is connected to the communication passage 79 connected between the check valve 75 and the relay valve 50, and supplies the pneumatic signal when the pressure in the communication passage 79 becomes equal to or higher than the upper limit value Pmax. I did it. Alternatively, the governor 21 may be connected between the relay valve 50 and the tank 71 or to the tank 71.

In the above embodiment, the control valve 51 is a pilot valve controlled by the pneumatic signal sent from the governor 21. Instead of this, an electromagnetic valve controlled by the brake control device may be used. The brake control device acquires a pressure detection value from a pressure sensor that detects the internal pressure of the tank 71 or the pressure of the flow path connected to the tank 71, and when the pressure becomes equal to or higher than the upper limit value Pmax, closes the control valve 51. The supply path 49 is shut off. By doing so, the pneumatic circuit can be configured without connecting the control valve 51 and the governor 21. Further, various controls such as opening and closing the control valve 51 according to the rising speed and the falling speed of the pressure detected by the pressure sensor can be performed.

In the above embodiment, the air conditioning section is the filter section 20 having the oil capturing filter 20A and the drying filter 20B. Instead of this, the air conditioning unit may be the oil trapping filter 20A only or the drying filter 20B only. Alternatively, it may be a refrigeration type (cooling type) dryer in which compressed air is cooled to room temperature or below to condense and separate water, oil, etc., and a permeation separation membrane type dryer using a hollow fiber of a polymer separation membrane. May be What is essential is that the trailer air supply system 12 has a function of suppressing malfunction in the downstream side of the air conditioning section.

In the above embodiment, the trailer air dryer 70 is connected in series with the tractor air dryer 17. Alternatively, the trailer air dryer 70 may be connected in parallel to the tractor air dryer 17. In this case, the tractor-side supply path 46 (see FIG. 1) is connected between the compressor 15 and the air dryer 17. According to this, as compared with the case where the tractor air dryer 17 and the trailer air dryer 70 are provided in series, the amount of air passing through the tractor air dryer 17 becomes smaller, so that the tractor air dryer 17 captures the air. The amount of impurities is also reduced. Therefore, the frequency of regenerating the tractor air dryer 17 can be reduced, and the amount of air consumed by the regeneration can be reduced.

In the above embodiment, the freight vehicle equipped with the pneumatic brake system 10 is a truck including a tractor and a trailer. Instead of this, the freight vehicle may be an articulated bus (joint bus) including a leading vehicle and a succeeding vehicle mechanically coupled to the leading vehicle. A plurality of towed vehicles such as trailers may be used.

10... Pneumatic brake system, 11... Tractor air supply system, 12... Trailer air supply system, 15... Compressor, 16... Tractor air supply passage, 17, 70... Air dryer, 18... Tank, 19... Protection valve, 20... Filter section as air conditioning section, 21... Governor, 22... Exhaust valve, 31-33... Air supply flow path, 34... Brake valve, 40, 41... Brake chamber as brake mechanism, 42... Chamber connection path, 45 ... Signal path, 46... Supply path, 48... Signal path as first supply path, 49... Supply path as second supply path, 49A... In-dryer supply path, 49B... Discharge path, 50... Relay as distribution section Valve: 51... Control valve, 52... First flow path forming member, 53... Second flow path forming member, 54... Hole portion, 55... Communication hole, 56... Input port, 57... Inlet flow path, 58... Valve seat , 59... Output port, 60... Exit flow passage, 61... Valve body, 62... Fitting hole, 71... Tank, 72... Control valve, 75... Check valve, 76... Discharge port, 77, 78... Signal supply path, 79... Communication passage.

Claims (4)

A trailer air supply system connected to a tractor air supply system via a connection,
A distribution unit that distributes air to a brake mechanism provided on a trailer wheel,
An air conditioning unit that is provided between the connection unit and the distribution unit and that cleans the air supplied from the tractor air supply system.
The distributor distributes air to the brake mechanism when air is supplied as an air pressure signal,
A first supply path connected to the connection part and supplying an air pressure signal to the distribution part;
A second supply path that is connected to the connection section and supplies air to the brake mechanism via the distribution section,
The air conditioning section is an air supply system for a trailer provided only in the second supply path . A discharge valve for discharging a fluid containing impurities generated by the regeneration when the air conditioning section is regenerated,
A control valve for controlling the supply of air to the air conditioning section,
A governor that outputs an air pressure signal to the discharge valve and the control valve,
The control valve shuts off the supply of air to the air conditioning section when the air pressure signal is input,
The trailer air supply system according to claim 1, wherein the discharge valve discharges the fluid containing the impurities when the air pressure signal is input. An air supply system for a trailer according to claim 1 or 2,
A vehicle air supply system comprising the tractor air supply system,
The flow path provided with the air conditioning section is connected in series to the flow path provided with the air conditioning section for a tractor via the connection section.
Air supply system for vehicles . An air supply system for a trailer according to claim 1 or 2,
A vehicle air supply system comprising the tractor air supply system,
The flow path provided with the air conditioning section is connected in parallel to the flow path provided with the air conditioning section for the tractor via the connection section.
Air supply system for vehicles .