JP5946644B2 - Air compressor system - Google Patents

Description

  The present invention relates to an air compressor system including an air compressor driven by engine power in a vehicle, for example.

  As a conventional air compressor system, for example, as described in Patent Document 1 below, an air compressor having an air compression function that is driven by engine power and compresses air in a vehicle, and air compressed by the air compressor are used. There is known an air tank that is stored and an unloader valve that is provided in the air compressor and stops an air compression function of the air compressor.

  In such an air compressor system, for example, when the air pressure in the air tank increases, the unloader valve is operated, and the air compressor returns the air sucked from the air intake port to the air intake port without being compressed. On the other hand, when the pressure of air in the air tank falls below a certain value, the unloader valve is deactivated, and the air compressor compresses the air and supplies it to the air tank.

JP 2000-192886 A

  Here, in the above air compressor system, as described above, when the air pressure in the air tank falls below a certain value, the engine power is taken out regardless of the engine operating condition and the air compressor is operated. Air is compressed. For this reason, in some cases, the operation of the air compressor may cause a deterioration in fuel consumption of the engine. Further, in recent compressor systems, there is a tendency for the demand for improvement in reliability to increase.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the air compressor system which can implement | achieve the fuel-consumption improvement of a vehicle, ensuring high reliability.

  In order to solve the above-described problems, an air compressor system according to the present invention includes an air compressor that is driven by engine power in a vehicle and has an air compression function for compressing air, and an air tank that stores air compressed by the air compressor. An unloader valve that is provided in the air compressor and stops the air compression function of the air compressor, an air flow path for flowing air from the air tank to the unloader valve, a regulator valve provided on the air flow path, A solenoid valve provided between the regulator valve and the unloader valve on the flow path, and a controller for controlling opening and closing of the solenoid valve, wherein the air pressure in the air tank is greater than the lower limit threshold and less than or equal to the upper limit threshold. When the vehicle is decelerating, the regulator valve is opened. By closing the solenoid valve by the control unit, the flow of the air to the unloader valve is stopped, the unloader valve is deactivated and the air compression function is activated, and the air pressure in the air tank is set to the lower threshold value. Larger than the upper threshold and when the vehicle is not decelerating, the regulator valve is opened and the solenoid valve is opened by the control unit, whereby the air is circulated to the unloader valve, and the unloader valve Is operated to stop the air compression function, and when the air pressure in the air tank reaches a critical threshold, the air is released to the atmosphere through a regulator valve.

  In the air compressor system of the present invention, while the operating rate of the air compressor is reduced when the vehicle is not decelerated, the deceleration energy can be actively used as the power of the air compressor when the vehicle is decelerated. As a result, it becomes possible to contribute to the improvement of the fuel consumption of the vehicle. In addition, even if, for example, the solenoid valve is fixed while closed, when the air pressure in the air tank reaches a critical threshold, the air is released to the atmosphere, so that the air tank can be prevented from being damaged. Therefore, it is possible to ensure high reliability of the air compressor system.

  Here, as a configuration that preferably achieves the above-described effects, specifically, the control unit is configured such that the fuel injection amount of the engine is 0, the foot brake of the vehicle is operated, and the exhaust brake function of the vehicle is The structure which opens a solenoid valve at the time of the deceleration driving | operation at least one when it is act | operating is mentioned.

  The regulator valve is preferably closed when the air pressure in the air tank is equal to or lower than the lower limit threshold. In this case, for example, even if the solenoid valve is stuck open, if the air pressure in the air tank is below the lower limit threshold, the regulator valve will be closed. Can be in a state. Therefore, it is possible to ensure higher reliability of the air compressor system.

  According to the present invention, it is possible to improve the fuel efficiency of a vehicle while ensuring high reliability.

It is the schematic which shows the air compressor system which concerns on one Embodiment of this invention. It is a graph which shows the operating pressure of the regulator valve in the air compressor system of FIG. It is a flowchart which shows operation | movement of the air compressor system of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted.

  FIG. 1 is a schematic view showing an air compressor system according to the embodiment, and FIG. 2 is a graph showing an operating pressure of a regulator valve. As shown in FIG. 1, an air compressor system 100 according to this embodiment is mounted on a vehicle such as a truck and supplies compressed air to an air brake (air brake) of the vehicle. The air compressor system 100 includes an air compressor 1, an air dryer 2, an air tank 3, a regulator valve 4, an electromagnetic valve 5, and a control unit 6.

  The air compressor 1 is driven by the power of a vehicle engine and has an air compression function for compressing air. The air compressor 1 here compresses the air in the cylinder 1b sucked from the air intake port 1c by reciprocating the piston 1a in the cylinder 1b by the rotation of the crankshaft connected to the engine, and the air exhaust port Exhaust from 1d.

  The air compressor 1 is provided with an unloader valve 7. The unloader valve 7 stops the air compression function, that is, switches the air compressor 1 from the load state to the unload state. The unloader valve 7 is operated by the pressure of the compressed air by supplying (circulating) the compressed air via the unloader pipe 8, and thereby the air intake port 1 c is always opened. As a result, in the air compressor 1, the air sucked from the air intake port 1c is returned to the air intake port 1c as it is without being compressed, and is operated in a no-load state.

  The air dryer 2 dehumidifies the compressed air compressed by the air compressor 1 and is connected to the air exhaust port 1 d of the air compressor 1. The air dryer 2 includes a purge valve 9 that communicates with the atmosphere. The air dryer 2 is not limited in its specifications and format, and various types can be adopted. The purge valve 9 is provided at the base in the air dryer 2 and discharges the generated water (condensed water) together with the compressed air. Further, the purge valve 9 here releases the compressed air in the air tank 3 to the outside (releases to the atmosphere) via the regulator valve 4 as will be described later.

  The air tank 3 stores the compressed air compressed by the air compressor 1 and is connected to the air dryer 2 via a check valve 10. The air tank 3 is provided with a supply port 3a for supplying filled compressed air to the outside. Further, the air tank 3 is provided with a pressure sensor 3b for detecting the pressure P of the compressed air in the air tank 3.

  The regulator valve 4 is a switching valve for allowing / blocking the flow of compressed air to the unloader pipe 8 according to the pressure of the air tank 3, and is connected to the air tank 3 via the air pipe 11, and is also connected to the unloader pipe 8. To the unloader valve 7. The air pipe 11 and the unloader pipe 8 constitute an air flow path 12 that circulates and supplies the compressed air of the air tank 3 to the unloader valve 7.

  As shown in FIG. 2, when the pressure (operating pressure) of the compressed air flowing through the regulator valve 4 here is less than or equal to the lower threshold P1, the open / close state of the regulator valve 4 is “closed (OFF)” and the operating pressure is When it is larger than the lower limit threshold value P1, the open / close state is set to “open (ON)”. In other words, the regulator valve 4 switches between opening and closing at the same lower limit threshold P1 both when the operating pressure increases and when the operating pressure decreases. The lower limit threshold value P1 is, for example, the lower limit value of the pressure required for the air brake of the vehicle.

  Returning to FIG. 1, the regulator valve 4 is connected to the purge valve 9 of the air dryer 2. When the operating pressure reaches the critical threshold value P <b> 3, the compressed air in the air tank 3 is released from the purge valve 9 to the atmosphere. The critical threshold value P3 is a set value for preventing damage to the air tank 3, and is set to a predetermined value based on the durable pressure value of the air tank 3, for example.

  The electromagnetic valve 5 allows / blocks the flow of the compressed gas in the unloader pipe 8 and controls the supply of compressed air to the unloader valve 7. The electromagnetic valve 5 is provided on the unloader pipe 8. That is, the electromagnetic valve 5 is provided between the regulator valve 4 and the unloader valve 7 on the air flow path 12.

  The control unit 6 includes, for example, a CPU, a ROM, a RAM, and the like. The controller 6 controls the opening and closing of the electromagnetic valve 5 based on the pressure P of the compressed air in the air tank 3 detected by the pressure sensor 3b of the air tank 3. In addition, the current fuel injection amount Q is detected from the fuel injection device (fuel injection ECU) of the engine, and the opening and closing of the electromagnetic valve 5 is controlled based on the fuel injection amount Q.

  Specifically, the control unit 6 closes the electromagnetic valve 5 when the pressure P of the compressed air in the air tank 3 is equal to or lower than the lower limit threshold value P1, and when the pressure P of the compressed air is larger than the upper limit threshold value P2. The solenoid valve 5 is opened. Further, the control unit 6 closes the solenoid valve 5 when the pressure P of the compressed air in the air tank 3 is larger than the lower limit threshold P1 and equal to or lower than the upper limit threshold P2 and the fuel injection amount Q of the engine is zero. Furthermore, the control unit 6 opens the solenoid valve 5 when the pressure P of the compressed air in the air tank 3 is greater than the lower limit threshold P1 and less than or equal to the upper limit threshold P2 and the fuel injection amount Q of the engine is greater than zero. And The upper limit threshold P2 is, for example, an upper limit value of pressure required for the air brake of the vehicle.

  In the air compressor system 100 configured as described above, when the engine is operated, as shown in the flowchart of FIG. 3, when the pressure P of the compressed air in the air tank 3 is equal to or lower than the lower limit threshold value P1 (P in S1) ≦ P1), the regulator valve 4 is closed, and the electromagnetic valve 5 is closed by the controller 6 (S2, S3). Thereby, the supply (circulation) of the compressed air to the unloader valve 7 is interrupted, and the unloader valve 7 is deactivated (S4). As a result, the air compressor 1 is loaded and the air is compressed by the air compressor 1, and the compressed air is supplied to the air tank 3 via the air dryer 2 and the check valve 10 to increase the pressure of the compressed air in the air tank 3. (S5).

  When pressure P of compressed air in air tank 3 is larger than upper limit threshold P2 (P1> P2 in S1), regulator valve 4 is opened and electromagnetic valve 5 is opened by control unit 6 ( S6, S7). Thereby, compressed air is supplied to the unloader valve 7, and the unloader valve 7 is operated (S8). As a result, the air compressor 1 is unloaded and the air compression function is stopped (S9). That is, the air compressor 1 returns to the air intake port 1c as it is without compressing the air from the air intake port 1c, and operates in a no-load state.

  When the pressure P of the compressed air in the air tank 3 is greater than the lower limit threshold P1 and not more than the upper limit threshold P2 (P1 <P ≦ P2 in S1), the regulator valve is opened (S10). When the fuel injection amount Q of the engine is 0 (Q = 0 in S11), the control unit 6 closes the electromagnetic valve 5 assuming that the vehicle is traveling at a reduced speed (S3). As a result, the supply of compressed air to the unloader valve 7 is cut off, the unloader valve 7 is deactivated, the air compressor 1 is loaded, and the air is compressed by the air compressor 1 (S4, S5).

  On the other hand, after S10, when the fuel injection amount Q of the engine is larger than 0 (Q> 0 in S11), the electromagnetic valve 5 is opened by the control unit 6 assuming that the vehicle is not decelerating. (S7). Thereby, compressed air is supplied to the unloader valve 7, the unloader valve 7 is operated, the air compressor 1 is unloaded, and the air compression function is stopped (S8, S9).

  As described above, in the air compressor system 100 according to the present embodiment, the operating rate of the air compressor 1 is reduced when the vehicle is not decelerated, while the deceleration energy that has been discarded as thermal energy is used as the power of the air compressor 1 when the vehicle is decelerated. Can be used actively (as much as possible). Thereby, it becomes possible to contribute to the improvement of the fuel consumption of the vehicle.

  Here, even if a malfunction occurs in the solenoid valve 5 and the solenoid valve 5 is stuck open, the regulator valve 4 is closed when the pressure P of the compressed air in the air tank 3 is lower than the lower threshold P1, The supply of compressed air to the unloader valve 7 is shut off. Therefore, in this case, the unloader valve 7 is deactivated, and the air compressor 1 can be reliably loaded (the air compression function is activated). On the other hand, even if the electromagnetic valve 5 is fixed while closed, when the pressure P of the compressed air in the air tank 3 reaches the critical threshold value P3, the compressed air is released to the atmosphere by the purge valve 9 via the regulator valve 4. Therefore, in this case, the air tank 3 can be prevented from being damaged.

  Therefore, according to the present embodiment, the deceleration energy of the vehicle is selectively used for the operation of the air compressor 1 to be regenerated, the drive energy of the air compressor 1 can be improved, and the fuel consumption of the vehicle can be improved. In addition to this, the regulator valve 4 (and the purge valve 9) can function as a backup mechanism when a malfunction occurs in the electromagnetic valve 5, and the reliability of the air compressor system 100 can be improved. As a result, it is possible to improve the fuel efficiency of the vehicle while ensuring high reliability.

  Further, in the air compressor system 100 of the present embodiment, an existing system can be used. For example, it is possible to establish the structure by adding only one electromagnetic valve 5. Therefore, the configuration can be simplified and the additional cost can be minimized.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. The present invention can be modified without departing from the scope described in the claims or applied to other embodiments. May be.

For example, in the above embodiment, when the fuel injection amount of the engine is 0, the electromagnetic valve 5 is closed by the control unit 6 when the vehicle is decelerating, but instead of or in addition to this, the foot brake of the vehicle The electromagnetic valve 5 may be closed by the control unit 6 when is operated and at least one of when the exhaust brake function of the vehicle is activated.

  Moreover, in the said embodiment, although the truck was illustrated as a vehicle, a bus | bath, a tractor, or another vehicle may be sufficient, for example. Moreover, in the said embodiment, although this invention is applied to an air brake, it is also possible to apply to an air suspension, a clutch, an air horn, an automatic door, or other air equipment. In the above description, “the fuel injection amount Q is 0” means a state in which fuel is not substantially injected, and an error in manufacturing and design is allowed.

  DESCRIPTION OF SYMBOLS 1 ... Air compressor, 3 ... Air tank, 4 ... Regulator valve, 5 ... Solenoid valve, 6 ... Control part, 7 ... Unloader valve, 9 ... Unloader pipe, 9 ... Purge pipe, 10 ... Check valve, 11 ... Air pipe, 12 ... Air flow path, 100 ... air compressor system.

Claims (3)

An air compressor driven by engine power in a vehicle and having an air compression function for compressing air;
An air tank for storing air compressed by the air compressor;
An unloader valve which is provided in the air compressor and which stops the air compression function of the air compressor;
An air flow path for circulating air from the air tank to the unloader valve;
A regulator valve provided on the air flow path;
A solenoid valve provided between the regulator valve and the unloader valve on the air flow path;
A controller for controlling opening and closing of the solenoid valve,
When the air pressure in the air tank is larger than the lower threshold and lower than the upper threshold and the vehicle is decelerating, the regulator valve is opened and the solenoid valve is closed by the control unit. The flow of the air to the unloader valve is stopped, the unloader valve is deactivated and the air compression function is activated,
When the air pressure in the air tank is greater than the lower limit threshold and less than or equal to the upper limit threshold and the vehicle is not decelerating, the regulator valve is opened and the electromagnetic valve is opened by the control unit. Thus, the air is circulated to the unloader valve, the unloader valve is activated, and the air compression function is stopped.
When the pressure of the air in the air tank reaches a critical threshold, the air is released to the atmosphere through the regulator valve. The control unit is configured such that when the fuel injection amount of the engine is 0, the foot brake of the vehicle is operated, and at least one of when the exhaust brake function of the vehicle is operated, the vehicle is The air compressor system according to claim 1, wherein the electromagnetic valve is closed during a deceleration operation.   3. The air compressor system according to claim 1, wherein the regulator valve is closed when an air pressure in the air tank is equal to or lower than a lower limit threshold value.

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