JPH0231787B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a compressed air start type engine.

The present invention provides a compressor connected to an output shaft of an engine via a clutch and driven by the engine, a reserve tank connected to the compressor to accumulate compressed air discharged from the compressor, and a compressor supplied from the reserve tank. An engine starting device that is operated by the compressed air to start the engine body, comprising: an operating state sensor that detects the operating state of the engine, a pressure sensor that detects the internal pressure of the reserve tank, and the operating state sensor. and a controller for controlling engagement and disengagement of the clutch based on the detection results of the pressure sensor and the detection result of the pressure sensor, and the controller controls deceleration such that the engine operating state is low load and high rotation based on the output of the operating state sensor. a deceleration operation determination means for determining whether or not the operating state is in operation; and a deceleration operation determination means for determining whether the internal pressure is in a first pressure state exceeding the upper limit setting pressure or below the upper limit setting pressure and above the lower limit setting pressure based on the output of the pressure sensor. a pressure state discriminating means for discriminating whether the pressure state is in the second pressure state or the third pressure state below the lower limit set pressure, the discrimination result of the deceleration operation discriminating means, and the discrimination result of the pressure state discriminating means. Based on the above, when the internal pressure of the reserve tank is in the first pressure state, the internal pressure of the reserve tank is in the second pressure state, and the operating state of the engine is not the deceleration operating state, the clutch is engaged. and when the internal pressure of the reserve tank is in the third pressure state and when the internal pressure of the reserve tank is in the second pressure state and the operating state of the engine is in the deceleration operating state. The gist of the present invention is a control device for a compressed air-start engine, characterized in that it includes a clutch engaging/disengaging means for engaging a clutch.

According to the present invention, it is possible to start the engine without using a conventional starting starter motor that requires a large current, so that the burden on the battery can be reduced.

Further, according to the present invention, a pressure sensor is provided to detect the internal pressure of the reserve tank, and when the internal pressure exceeds the upper limit set pressure, the clutch is disengaged and the compressor is always in a non-operating state. Problems such as damage to the air passage piping system due to high pressure are prevented, and when the internal pressure is below the lower limit set pressure, the clutch is engaged to keep the compressor in constant operation. The internal pressure of the reserve tank is quickly increased to enable reliable starting even when the elapsed time until the next start is relatively short, and furthermore, when the internal pressure is between the lower limit set pressure and upper limit set pressure, The compressor is activated during deceleration operation and deactivated during other operating conditions, which increases the engine braking effect, suppresses the increase in engine load when the power is turned on, and reduces energy loss. play.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

1 and 2 show an embodiment of the present invention. In FIG. 1, an engine main body 2 is provided on a crankshaft 3 and has a pulley 4 that rotates together with the crankshaft 3. As shown in FIG. A compressor 10 is configured to compress and discharge air drawn from a pipe 6 communicating with an atmospheric pressure space into a pipe 8 through an air cleaner device (not shown) or the like, and is driven by a pulley to be driven by the engine body 2. 12 and belt 1
An electromagnetic clutch 16 is interposed between the pulley 12 and the compressor 10 to connect the pulley 12 to the compressor 10.
The transmission of the driving force to 0 can be freely connected and disconnected. In addition, the pipe line 8 is connected to the reserve tank 18 in order to supply the compressed air discharged from the compressor 10 into the reserve tank 18, and also allows the compressed air to flow only from the compressor 10 side to the reserve tank 18 side. A check valve 20 is provided to prevent backflow of the compressed air.

On the other hand, the reserve tank 18 is also communicated with the starter 26 via a conduit 24, and the conduit 24 is provided with a solenoid valve 28, so that communication with the starter 26 can be opened and closed.

The engine starting device 26 is composed of a turbine device etc. that is operated by compressed air supplied from the reserve tank 18 when the solenoid valve 28 is opened. 36, and the same gear 36 is connected to the crankshaft 3 of the engine body 2.
It meshes with a ring gear 35 provided on the outer periphery of a flywheel 34 fixed to the.

In addition, the electromagnetic clutch 16 and the electromagnetic valve 28
The microprocessor 38 is controlled by a microprocessor 38 that functions as a controller, and the microprocessor 38 also processes an output signal Pr from a pressure sensor 40 that detects the pressure in the reserve tank 18, and a starter (not shown) that detects the driver's starting operation. An output signal Ssw of the switch, an output signal Nr of an engine speed sensor (not shown) as a driving state sensor that detects the speed of the engine body 2, and a driving state sensor (not shown) that detects the fully closed state of a throttle valve (not shown). The output signal Isw of the idle switch is used as an input element, and its operation is represented by the flowchart shown in FIG.

Execution of the flowchart in FIG. 2 is started by an interrupt signal every set time (for example, 100 msec). Then, in step S1, each detection signal Pr, Ssw,
Nr and Isw are read respectively, and in step S2, the starter switch is turned on and off by the detection signal Ssw.
When it is determined that the starter switch is OFF and the starter switch is ON, the process goes to step S11 and the engine starting device 26 is activated by the compressed air stored in the reserve tank 18.
The program is ended by opening the solenoid valve 28 to start the engine body 2. When the starter switch is OFF, the process proceeds to step S3, where the solenoid valve 28 is closed, and in step S4, the rotation speed Nr of the engine body 2 and the first set engine rotation speed N1 (for example, 100 to
300 rpm), it is determined whether or not the engine main body 2 is in operation. If Nr>N1, it is determined that the engine body 2 is not in operation, and the electromagnetic clutch 16 is released in step S5, thereby terminating the program.

When Nr>N1, it is determined that the engine body 2 is in operation, and in step S6, the pressure Pr in the reserve tank 18 is compared with the upper limit setting pressure P1 stored in the ROM in advance. When Pr>P1, it is determined that the pressure of the compressed air stored in the reserve tank 18 has reached the upper limit value, the electromagnetic clutch 16 is released, and the program is terminated. Pr
>P1, it is determined that the pressure of the compressed air stored in the reserve tank 18 is below the upper limit value, and in step S7, the pressure of the compressed air stored in the reserve tank 18 is
The pressure Pr in 8 is compared with the lower limit set pressure P2, which is smaller than the upper limit set pressure P1, and which is stored in advance in the ROM. When Pr<P2, it is determined that the pressure of the compressed air stored in the reserve tank 18 is below the lower limit value, and the compressor 1 is operated to supply compressed air to the reserve tank 18 in step S8.
The program ends by engaging electromagnetic clutch 16 to drive 0.

If Pr<P2, it is determined that the pressure of the compressed air stored in the reserve tank 18 is equal to or higher than the lower limit value, and in step S9, it is determined by the detection signal Isw whether the throttle valve (not shown) is fully closed. Discern. When the detection signal Isw is OFF, it is determined that the throttle valve (not shown) is not fully closed, and the electromagnetic clutch 16 is released in step S5, thereby terminating the program.

When the detection signal Isw is ON, it is determined that the throttle valve (not shown) is fully closed, and the step
In S10, the rotation speed Nr of the engine body 2 and the second set engine rotation speed N2 (for example,
1500~2000rpm), the engine body 2
Determine whether or not the vehicle is decelerating. When Nr>N2, it is determined that the engine body 2 is decelerating, and in step S8, the electromagnetic clutch 16 is engaged to supply compressed air into the reserve tank 18, and the program is terminated.

If Nr>N2, it is determined that the engine body 2 is not decelerating, and the electromagnetic clutch 16 is released in step S5, and the program is terminated. In this embodiment, the function as a pressure state determining means is fulfilled by making the determinations in step S6 and step S7, and the function as a deceleration operation determining means is fulfilled by making the determinations in step S9 and step S10. The electromagnetic clutch 16 is engaged and disengaged in steps S5 and S6 based on the determination results in steps S6, S7, S9 and S10, thereby fulfilling its function as a clutch engagement and disengagement means. It is configured so that According to the above configuration, when the starter switch (not shown) is turned ON when starting the engine, the solenoid valve 28 is opened, so the drive shaft 30 of the starter 26 is rotated by the compressed air stored in the reserve tank 18, and the drive shaft 30 of the starter 26 is rotated. Since the torque generated by the rotation is transmitted to the ring gear 35 via the one-way clutch 32, the engine main body 2 can be started. Note that once the engine is started, the presence of the one-way clutch 32 prevents the rotational torque of the engine from being transmitted to the starter 26 via the ring gear 35.

Furthermore, during engine operation, when the pressure Pr in the reserve tank 18 is between the upper limit set pressure P1 and the lower limit set pressure P2, the electromagnetic The compressor 1 engages the clutch 16 to supply compressed air into the reserve tank 18.
0, and in cases other than the above, the electromagnetic clutch 16 is released to stop the operation of the compressor 10, and the pressure Pr in the reserve tank 18 is always maintained at P1≧
It is adjusted so that Pr≧P2.

Therefore, according to the above embodiment, the compressed air discharged from the compressor 10 driven by the engine body 2 is stored in the reserve tank 18 while the engine body 2 is in operation, and the solenoid valve 28 is activated when the engine body 2 is started. When opened, compressed air is supplied from the reserve tank 18 to the engine starting device 26 and the engine starting device 26 is operated to start the engine body 2, which is effective in effectively utilizing energy. .

Also, if the pressure Pr in the reserve tank 18 is P1≧
When Pr≧P2, compressor 10 only during deceleration
is driven, the engine braking effect is increased and the power loss required for accumulating pressure is reduced. moreover,
Since there is no need to use a conventional starter motor that requires a large current, it also has the effect of reducing the burden on the battery.

[Brief explanation of drawings]

FIG. 1 is a structural explanatory diagram showing one embodiment of the present invention;
FIG. 2 is a flowchart showing the control process of the apparatus of the above embodiment. 2...Engine body, 10...Compressor,
16... Electromagnetic clutch, 18... Reserve tank, 26... Engine starting device, 28... Solenoid valve, 38... Microprocessor.

Claims (1)

[Claims] 1 A compressor connected to the output shaft of the engine via a clutch and driven by the engine;
A reserve tank communicated with the compressor for accumulating compressed air discharged from the compressor, and an engine starting device that starts the engine body by being operated by the compressed air supplied from the reserve tank, an operating state sensor that detects the operating state of the engine; a pressure sensor that detects the internal pressure of the reserve tank;
a controller for controlling engagement and disengagement of the clutch based on the detection result of the operating state sensor and the detection result of the pressure sensor;
a deceleration operation determination means for determining whether or not the engine operation condition is a deceleration operation state with low load and high rotation based on the output of the operation condition sensor; a first pressure state exceeding the upper limit set pressure, a second pressure state below the upper limit set pressure and above the lower limit set pressure, or a third pressure state below the lower limit set pressure. Discrimination means;
Based on the determination result of the deceleration operation determination means and the determination result of the pressure state determination means, when the internal pressure of the reserve tank is in the first pressure state and when the internal pressure of the reserve tank is in the second pressure state. The clutch is disengaged when the operating state of the engine is not the deceleration operating state, and when the internal pressure of the reserve tank is at the third pressure state and when the internal pressure of the reserve tank is at the second pressure state. A control device for a compressed air-start engine, characterized in that the control device includes a clutch engaging/disengaging means for engaging and disengaging the clutch when the engine is in the deceleration operating state.