JP2009056954A - Controller for air compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To compensate for the defficiency of the absorption power of a brake by applying a load on an engine by continuously operating an air compressor without making the air compressor non-operative at the time of the deceleration of a vehicle. <P>SOLUTION: A controller for an air compressor comprises an air compressor 2 driven by an engine 1 mounted to a vehicle so as to compress air, a main air tank 6 and a sub-air tank 7 connected in parallel with the air compressor 2 so as to store compressed air, a changeover valve 9 having a first position where the compressed air from the air compressor 2 is supplied the sub-air tank 7 and a control means 12 for use in the control of the changeover valve 9. The control means 12 changes over the changeover valve 9 to the first position where the compressed air from the air compressor 2 is supplied to the main air tank 6 at the time of running except the deceleration time of the vehicle and changed over the change valve 9 to a second position where the compressed air from the air compressor 2 is supplied to the sub-air tank 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an apparatus for controlling an air compressor driven by an engine mounted on a vehicle.

  In general, in medium and large-sized vehicles (so-called ordinary trucks), pneumatic boosters that use compressed air are used as boosters for brakes, clutches, and the like. The compressed air is supplied by an air compressor connected to the engine and stored in an air tank. When the pressure in the air tank reaches a predetermined pressure, the unloader of the air compressor is activated and the supply of compressed air to the air tank is stopped. When the air tank and the unloader of the air compressor are connected by piping, and the indicated pressure from the air tank (pressure in the air tank) reaches a predetermined pressure, the piston of the unloader governor provided in the piping connecting the air tank and the unloader The intake valve of the air compressor is pushed open, the cylinder chamber of the air compressor is opened to the atmosphere, and the supply of compressed air to the air tank is stopped (see Patent Document 1, etc.).

JP 2003-276591 A

  In general, medium- and large-sized vehicles have a large vehicle weight (loading weight), and medium- and large-sized vehicles use a high-charged engine with a small displacement to ensure fuel-saving performance. In medium- and large-sized vehicles with small engine displacement, the engine brake and exhaust brake (exhaust brake) torque decreases, and the horsepower for absorbing the brake tends to be insufficient. Therefore, it is conceivable to compensate for the deficiency in the absorption horsepower of the brake by operating the air compressor during deceleration of the vehicle on which the engine brake or the exhaust brake operates, and applying a load to the engine.

  However, if the pressure in the air tank reaches a predetermined pressure when the vehicle is decelerating, the air compressor unloader is activated and the air compressor is inactive (unloaded). I can't.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an air compressor capable of compensating for a deficiency in the absorption horsepower of a brake by applying a load to the engine by continuously operating the air compressor without deactivating it when the vehicle is decelerated. It is to provide a control device.

  In order to achieve the above object, the present invention is an air compressor that is driven by an engine mounted on a vehicle and compresses air, and a main air tank and a sub air tank that are connected in parallel to the air compressor and store compressed air. A switching valve having a first position for supplying compressed air from the air compressor to the main air tank and a second position for supplying compressed air from the air compressor to the sub air tank, and control for controlling the switching valve And the control means switches the switching valve to the first position for supplying compressed air from the air compressor to the main air tank during traveling except when the vehicle decelerates, and decelerates the vehicle. Sometimes, the switching valve is in the second position for supplying compressed air from the air compressor to the sub air tank. It is intended to switch.

  Here, when the pressure in the sub air tank reaches a predetermined pressure while the switching valve is in the second position during deceleration of the vehicle, the control means moves the switching valve from the second position to the first position. It may be switched to one position.

  The vehicle may be decelerated when the accelerator is not stepped on, the clutch is in the engaged state, and the transmission is in the gear-in state.

  According to the present invention, a control device for an air compressor that can make up for a shortage of the absorption horsepower of a brake by applying a load to the engine by continuously operating the air compressor without deactivating it when the vehicle decelerates. It is possible to provide an excellent effect.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram of a control device for an air compressor according to an embodiment of the present invention.

  In FIG. 1, 1 is an engine (diesel engine) mounted on a vehicle (truck) (not shown), and 2 is an air compressor that is driven by the engine 1 and compresses air.

  The air compressor 2 according to this embodiment is a reciprocating type air compressor having a cylinder chamber, a piston that reciprocates in the cylinder chamber, and a crankshaft that drives the piston. An intake pipe 3 is connected to the intake port of the air compressor 2, and a supply pipe 4 is connected to the discharge port of the air compressor 2. The crankshaft of the air compressor 2 is connected to the crankshaft of the engine 1 via a belt or the like.

  An air filter 5 is disposed in the intake pipe 3 connected to the air compressor 2. A supply pipe 4 connected to the air compressor 2 includes a main air tank (wet air tank) 6 that stores air (compressed air) compressed by the air compressor 2 and a sub air tank 7 that stores compressed air from the air compressor 2. Are arranged in parallel. In the present embodiment, the sub air tank 7 is set to have the same capacity as the main air tank 6.

  The supply pipe 4 connecting the main air tank 6 and the sub air tank 7 and the air compressor 2 is provided with a silencer, an air dryer, a check valve and the like (not shown). The check valve allows the flow of compressed air from the air compressor 2 to the main air tank 6 and the sub air tank 7 and blocks the flow of compressed air from the main air tank 6 and the sub air tank 7 to the air compressor 2. ing.

  The air compressor 2 sucks air into the cylinder chamber via an air filter 5 disposed in the intake pipe 3 and compresses the air in the cylinder chamber by a piston that reciprocates in the cylinder chamber. The compressed air from the air compressor 2 is supplied to various devices driven by the compressed air through a protection valve (4-way protection valve) 17 disposed in the supply pipe 4. Examples of the various devices include an air suspension system mounted on a vehicle, a clutch booster (clutch booster), an exhaust brake device, a transmission shift device, and the like (not shown).

  Compressed air from the air compressor 2 is supplied to the main air tank 6 through a supply pipe 4 connecting the main air tank 6 and the air compressor 2 and is temporarily stored in the main air tank 6. The compressed air from the air compressor 2 is supplied to the sub air tank 7 through the supply pipe 4 connecting the sub air tank 7 and the air compressor 2, and is temporarily stored in the sub air tank 7.

  When the pressure in the main air tank 6 or the sub air tank 7 reaches the first predetermined pressure (non-operating pressure of the air compressor 2) P1, the air compressor 2 makes the air compressor 2 inactive (unloaded), When the pressure in the main air tank 6 or the sub air tank 7 decreases and reaches a second predetermined pressure (operating pressure of the air compressor 2) P2 (P2 <P1) lower than the first predetermined pressure P1, the air compressor 2 is turned on. It has the unloader 18 made into an operation state (load state). The unloader 18 of the air compressor 2 is connected to the main air tank 6 and the sub air tank 7 by an indicated pressure introduction pipe 8.

  The unloader 18 is used when the command pressure from the main air tank 6 or the sub air tank 7 (pressure in the main air tank 6 or the sub air tank 7) reaches the first predetermined pressure P1 when the air compressor 2 is in an operating state. The piston of the unloader governor to which the pressure in the command pressure introduction pipe 8 acts pushes the intake valve of the air compressor 2 open, and the cylinder chamber of the air compressor 2 is opened to the atmosphere. As a result, the air compressor 2 enters a non-operating state in which compression work is not performed, and supply of compressed air to the main air tank 6 or the sub air tank 7 is stopped.

  Since the crankshaft of the air compressor 2 is always rotated by the crankshaft of the engine 1 when the engine 1 is operating, when the unloader 18 is operating (when the air compressor 2 is not operating), the air in the intake pipe 3 is As the piston reciprocates, the inflow and outflow of the cylinder chamber are repeated. Therefore, the air compressor 2 connected to the engine 1 does not perform compression work when in an inoperative state.

  On the other hand, when the air compressor 2 is not in operation, the command pressure from the main air tank 6 or the sub air tank 7 (the pressure in the main air tank 6 or the sub air tank 7) decreases to reach the second predetermined pressure P2. In this case, since the intake valve of the air compressor 2 that has been pushed by the piston of the unloader governor is closed, the air compressor 2 is activated, and the main air tank 6 or the sub air tank 7 is filled with the compressed air from the air compressor 2. Is done.

  The control device according to this embodiment includes a first switching valve 9 disposed in a supply pipe 4 that connects the air compressor 2 and the main air tank 6 and the sub air tank 7, and the main air tank 6, the sub air tank 7, and the air compressor 2. A second switching valve 10 disposed in the command pressure introduction pipe 8 connecting the unloader 18, a first switching pipe disposed in the supply pipe 4 connecting the main air tank 6, the sub air tank 7, and the protection valve 17 (the above-described various devices). The three switching valve 11 and the controller (control means) 12 which controls these 1st switching valve 9, the 2nd switching valve 10, and the 3rd switching valve 11 are provided.

  The first switching valve 9 is an electromagnetic valve, and has a first position for supplying compressed air from the air compressor 2 to the main air tank 6 and a second position for supplying compressed air from the air compressor 2 to the sub air tank 7. Have. In the present embodiment, when the first switching valve 9 is turned on (energized to the electromagnetic solenoid), the first switching valve 9 is switched to the first position for supplying the compressed air from the air compressor 2 to the main air tank 6 and turned off (energization of the electromagnetic solenoid). And the second position for supplying the compressed air from the air compressor 2 to the sub air tank 7 is configured.

  The second switching valve 10 is an electromagnetic valve, a first position for introducing the command pressure from the main air tank 6 (pressure in the main air tank 6) into the unloader 18 of the air compressor 2, and the command pressure from the sub air tank 7 ( And a second position at which the pressure in the sub air tank 7 is introduced into the unloader 18 of the air compressor 2. In the present embodiment, the second switching valve 10 is switched to the first position where the command pressure from the main air tank 6 (pressure in the main air tank 6) is introduced into the unloader 18 of the air compressor 2 when turned on, and the sub air tank when turned off. 7 is configured to be switched to the second position at which the indicated pressure from 7 (pressure in the sub air tank 7) is introduced into the unloader 18 of the air compressor 2.

  The third switching valve 11 is an electromagnetic valve, and supplies the compressed air stored in the main air tank 6 to the various devices, and the compressed air stored in the sub air tank 7 to the various devices. And a second position. In the present embodiment, the third switching valve 11 is switched to the first position for supplying the compressed air stored in the main air tank 6 to the various devices when turned on, and the compressed air stored in the sub air tank 7 when turned off. Is configured to be switched to a second position for supplying the above-mentioned various devices.

  The sub air tank 7 is provided with a pressure sensor 13 for detecting the pressure in the sub air tank 7, and a detection signal from the pressure sensor 13 is input to the controller 12.

  The operation of the first switching valve 9, the second switching valve 10, and the third switching valve 11 of this embodiment will be described.

  In the present embodiment, the controller 12 switches the first switching valve 9, the second switching valve 10, and the third switching valve 11 to the first position during traveling except when the vehicle is decelerating, so that the air compressor 2 is switched to the main air tank. 6, the compressed air from the air compressor 2 is supplied to the main air tank 6 and filled, while the first switching valve 9, the second switching valve 10 and the third switching valve 11 are respectively connected to the first switching valve 9, when the vehicle is decelerated. By switching to the two positions, the air compressor 2 is connected to the sub air tank 7, and the compressed air from the air compressor 2 is preferentially supplied to the sub air tank 7 for filling.

  In addition, the controller 12 has the first switching valve 9, the second switching valve 10, and the third switching valve 11 in the second position when the vehicle is decelerated. When the pressure reaches the first predetermined pressure P1, the first switching valve 9, the second switching valve 10 and the third switching valve 11 are switched from the second position to the first position, respectively, and the air compressor 2 is switched to the main air tank 6. Connected, the compressed air from the air compressor 2 is supplied to the main air tank 6 and filled.

  In this embodiment, the controller 12 is in a state where the accelerator is not stepped on (the accelerator switch 14 is off), the clutch is in the engaged state (the clutch switch 15 is off), and the transmission is in the gear-in state (neutral). It is determined that the vehicle is decelerating when the engine brake or the exhaust brake device in which the switch 16 is off is activated.

  In short, according to the present embodiment, the main air tank 6 and the sub air tank 7 are connected in parallel to the air compressor 2, and the compressed air from the air compressor 2 is supplied to the main air tank 6 and filled during traveling except when the vehicle is decelerated. At the time of deceleration of the vehicle where the brake (engine brake, exhaust brake device, etc.) is operated, the compressed air from the air compressor 2 is preferentially supplied to the sub air tank 7 for filling. The sub air tank 7 that is filled with compressed air when the vehicle is decelerated relatively short compared to when traveling is less likely to become full compared to the main air tank 6, and the air compressor 2 is not operated when the vehicle decelerates. It becomes possible to operate continuously without doing. Therefore, the air compressor 2 can be continuously operated when the vehicle is decelerated, and a load on the engine 1 can be applied to compensate for the shortage of the absorption horsepower of the brake.

  According to the present embodiment, the compressed air from the air compressor 2 is supplied and filled in the main air tank 6 during traveling except when the vehicle is decelerating. The main air tank 6 that is filled with compressed air during traveling except when the vehicle is decelerating is always kept almost full. Therefore, the operation frequency of the air compressor 2 when accelerating a vehicle that requires a large driving torque can be reduced, and fuel saving performance can be ensured.

  Next, the processing flow by the controller 12 will be described with reference to FIG.

  FIG. 2 is a process flowchart by the controller.

  This processing flow is executed when the first switching valve 9, the second switching valve 10, and the third switching valve 11 are in the first position on the main air tank 6, and when the processing flow is terminated, The one switching valve 9, the second switching valve 10, and the third switching valve 11 are switched to the first position on the main air tank 6 side.

  In step S1, the controller 12 determines whether or not the accelerator switch 14 is off. When the accelerator switch 14 is off, the controller 12 proceeds to step S2, and when the accelerator switch 14 is on, the process flow is terminated.

  In step S2, the controller 12 determines whether or not the clutch switch 15 is off. When the clutch switch 15 is off, the controller 12 proceeds to step S3, and when the clutch switch 15 is on, this processing flow is terminated.

  In step S3, the controller 12 determines whether or not the neutral switch 16 is off. If the neutral switch 16 is off, the controller 12 proceeds to step S4, and if the neutral switch 16 is on, the process flow ends.

  In step S4, the controller 12 switches the first switching valve 9, the second switching valve 10, and the third switching valve 11 from the first position on the main tank 6 side to the second position on the sub air tank 7 side, and the air compressor 2 The various devices (the first switching valve 9, the second switching valve 10 and the third switching valve 11) are connected to the sub air tank 7, and the sub air tank 7 is filled with the compressed air from the air compressor 2, and the sub air tank 7 The compressed air stored in the inside is supplied to the various devices.

  In step S5, the controller 12 determines whether or not the sub air tank 7 is full. When the pressure in the sub air tank 7 detected by the pressure sensor 13 is equal to or higher than the first predetermined pressure P1 (the sub air tank 7 is full), the controller 12 ends this processing flow, and the pressure sensor 13 If the detected pressure in the sub air tank 7 is smaller than the first predetermined pressure P1 (the sub air tank 7 is not full), the process proceeds to step S6.

  In step S <b> 6, the controller 12 determines whether or not the pressure in the sub air tank 7 detected by the pressure sensor 13 is smaller than the minimum guaranteed operating pressure x of the sub air tank 7. When the pressure in the sub air tank 7 is smaller than the minimum guaranteed operating pressure x of the sub air tank 7, the controller 12 ends this processing flow, and the pressure in the sub air tank 7 is equal to or higher than the minimum guaranteed operating pressure x of the sub air tank 7. If so, the process returns to step S1.

Here, the minimum guaranteed operating pressure x (e.g., 6 kg / cm ²⁾ is normally actuated without value for the component pressure drop of the various devices driven by compressed air (e.g., 5.5 kg / cm ² As described above, the value is set to a value equal to or lower than a value (for example, 10 kg / cm ² ) at which the components of the various devices driven by compressed air are damaged due to high pressure.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various other embodiments can be adopted.

  In the above embodiment, the sub air tank 7 is set to have the same capacity as the main air tank 6, but the present invention is not limited to this, and the sub air tank 7 may be set to a capacity different from that of the main air tank 6.

It is the schematic of the control apparatus of the air compressor which concerns on one Embodiment of this invention. It is a process flowchart by a controller.

Explanation of symbols

1 Engine 2 Air compressor 6 Main air tank (wet air tank)
7 Sub air tank 9 1st switching valve (switching valve)
12 Controller (control means)

Claims (3)

An air compressor that is driven by an engine mounted on a vehicle and compresses air; a main air tank and a sub air tank that are connected in parallel to the air compressor and store compressed air; and the compressed air from the air compressor is used as the main air tank A switching valve having a first position for supplying the compressed air from the air compressor and a second position for supplying the compressed air from the air compressor to the sub air tank, and a control means for controlling the switching valve,
The control means switches the switching valve to the first position for supplying compressed air from the air compressor to the main air tank during traveling except when the vehicle is decelerating, and when the vehicle is decelerating, the switching valve. Is switched to the second position for supplying compressed air from the air compressor to the sub air tank.   The control means moves the switching valve from the second position to the first position when the pressure in the sub air tank reaches a predetermined pressure while the switching valve is in the second position during deceleration of the vehicle. The air compressor control device according to claim 1 to be switched.   3. The air compressor control device according to claim 1, wherein when the vehicle is decelerated, the accelerator is not stepped on, the clutch is in an engaged state, and the transmission is in a gear-in state. 4. .

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