JP6027733B2 - Engine automatic stop start device - Google Patents

Description

  The present invention relates to an apparatus for improving fuel efficiency and reducing the complexity of a driver's operation by executing automatic stop / restart of an engine mounted on a vehicle.

  An automatic transmission (hereinafter referred to as A / T) that automatically switches a gear ratio in accordance with the speed of an automobile and the number of revolutions of an engine is widely known and adopted in many automobiles. One type of A / T is the torque converter type A / T, which combines a torque converter and planetary gears to automatically shift gears by hydraulic control. The torque converter type A / T is not only used for passenger cars, It is also used for route buses and delivery trucks that require repeated stops.

By the way, in a route bus equipped with A / T, when the vehicle stops, an automatic engine stop / start device (commonly referred to as an “ISS device” hereinafter) is operated to stop the engine.
However, even at an pedestrian crossing such as an intersection, even if the pedestrian stops waiting for the passage of pedestrians, the vehicle may stop idling regardless of the driver's intention, and may not start immediately.
Therefore, if you do not want to stop idling, you must continue to step on the brake pedal (see reference numeral 24 in FIG. 2) while stepping on the foot switch (see reference numeral 25 in FIG. 2) before stopping the vehicle. There is a driver who refrains from the ISS device by causing the driver to perform complicated operations.

Therefore, the technique disclosed in Japanese Patent Application Laid-Open No. 2001-12269 (Patent Document 1) includes two or more sensors for detecting the presence or absence of a brake operation and a plurality of sensors from each sensor in an engine automatic stop / automatic restart device. The presence / absence of a brake operation is determined based on the brake operation presence / absence signal.
In this way, if the brake switch fails for any reason, the brake pedal signal will remain off and the engine will not automatically stop even if the automatic stop condition is met. It is preventing.
Further, there is a technical disclosure for preventing the engine from automatically stopping even if the brake pedal is not operated and satisfying the automatic stop condition.

  Further, the technique disclosed in Japanese Patent Application Laid-Open No. 2004-124923 (Patent Document 2) includes a brake switch that detects the operation of the brake and a brake oil pressure detection sensor that detects the oil pressure of the brake, and the engine start request is determined. In this case, the operation of the brake by the brake switch is detected, and when the hydraulic pressure detected by the brake hydraulic pressure sensor is greater than or equal to a predetermined value, it is determined that the engine is started, thereby reliably preventing inadvertent movement of the vehicle. In addition, even when a driving force is generated by starting the engine, a technical disclosure is made so that a shock or the like is not transmitted to the driver.

JP 2001-12269 A JP 2004-124923 A

  However, the technique disclosed in Patent Document 1 determines whether or not a brake operation is performed based on a plurality of brake operation presence / absence signals so that a predetermined condition for automatic stop is not erroneously determined even when a failure occurs in the brake switch. Therefore, depending on the running state of the vehicle, it is not possible to stop the idle stop (continue idling) or stop the engine at the driver's will.

  In addition, the technique disclosed in Patent Document 2 determines that the brake is operating reliably by using a brake switch that detects the operation of the brake and a brake oil pressure detection sensor that detects the oil pressure of the brake. In addition to reliably preventing inadvertent movement of the vehicle at start-up and preventing the driver from receiving shocks, etc., even if driving force is generated by starting the engine, the idle stop is stopped depending on the running state of the vehicle ( It is not possible to continue idling) or stop the engine at the driver's will.

  In order to solve the above-described problems, in the present invention, in the running state of the vehicle, based on the driver's intention, the operation of continuing the engine idle operation or the operation of stopping the engine can be simplified to facilitate the use of the ISS device. Thus, an object is to reduce the heavy use of environmental technology and the complexity of the operation of the driver.

In order to solve the above problems, in the present invention, in an automatic stop start device for an engine that automatically stops or automatically starts an engine mounted on a vehicle,
An air tank mounted on the vehicle for storing compressed air;
A brake booster that converts the compressed air into high-pressure hydraulic pressure and supplies it to the brake;
An air line connecting the air tank and the brake booster;
A brake valve that is provided in the air pipe and outputs compressed air from the air tank at a pressure corresponding to the amount of depression of the brake pedal;
An air pressure detecting means that is disposed between the brake valve and the brake booster in the air line and detects an air pressure output from the brake valve;
Engine control means capable of automatically stopping and automatically starting the engine;
Based on the detected value of the detected air pressure, an engine automatic stop or start control means for outputting an engine automatic stop or automatic start to the engine control means;
A foot switch having a function of temporarily canceling the operation of the automatic stop and start device of the engine,
The automatic stop / start control means outputs a signal for lighting a stop lamp of the vehicle when the air pressure detecting means detects an air pressure equal to or higher than a first threshold, and the foot switch is turned on before the vehicle stops. When stepped on, the engine automatic stop is stopped while the foot switch is stepped on,
When the foot switch is not stepped on and the air pressure detection means detects an air pressure that is greater than the first threshold value and less than a second threshold value , engine operation is continued, and the air pressure detection means is activated by the second threshold value. The engine control means is controlled to stop the engine when the above air pressure is detected.

  According to this invention, conventionally, in the case of an instantaneous pause or a pause on a gentle slope, the driver operates the brake pedal so as not to stop the engine and the foot switch so as not to stop idling. The vehicle must be stepped on before the vehicle stops, and the operation is complicated, which may affect the driver's fatigue and further the safe driving, and the complexity of these operations can be eliminated.

  By adopting such a structure, it is possible to continue engine operation or stop the engine by changing the amount of operation of the brake pedal based on the intention of the driver. Since the engine was stopped at the stop of the car against the intention of the driver, it was possible to start as soon as the pedestrian crossed. Further, since engine stall does not occur on slopes and the like, there is no occurrence of rearward movement of the vehicle, and safe driving with respect to getting on and off of pedestrians and passengers of the own vehicle is improved.

  In the present invention, it is preferable that the automatic stop / start control means of the engine outputs a signal for lighting a stop lamp of the vehicle at an initial stage when the air pressure detection means starts to detect a pressure increase. Good.

  By adopting such a structure, a signal for turning on the stop lamp is output from the automatic stop / start control means of the engine according to the detected pressure of the air pressure detecting means, so that a stop lamp switch is not required and the cost is reduced. It becomes possible.

Because the air pressure detection means that detects the air pressure output from the brake valve that changes the air pressure depending on the amount of depression of the brake pedal, the engine can be automatically stopped based on the detected value of the air pressure. In the running state of the vehicle, based on the driver's intention, the continuation of the engine idle operation or the engine stop operation is simplified, and the use of the ISS device is facilitated to promote the environmental improvement accompanying the fuel saving. Thus, safe driving can be improved by reducing the complexity of the driver's operation.

It is a perspective view of a route bus to which an automatic stop / start device for an engine of the present invention is applied. The schematic explanatory drawing around the driver's seat of the FIG. 1A section by which the operating device of this invention is arrange | positioned is shown. It is the block diagram which showed the structure of the engine automatic stop start apparatus in the Example of this invention. The explanatory view of the output characteristic of the air pressure with respect to the brake pedal depression amount of the brake valve in this embodiment is shown. It is a block diagram which shows schematic structure of the brake device in this embodiment. (A) is an idling continuation condition diagram due to air pressure in the present embodiment, and (B) is an idling stop condition diagram due to air pressure.

Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.
Further, in the case of showing the directionality of the description, “up and down direction”, “left and right direction” and “front and back direction” are described with reference to the state of being seated in the driver's seat.

FIG. 1 is a perspective view of a route bus equipped with an automatic transmission (hereinafter referred to as “A / T”) to which the brake device of the present invention is applied. The bus 1 as a vehicle has a front door 1a disposed on the front side of the front wheel 1a and an intermediate door 1b disposed on the front side of the rear wheel 1d. The front door 1a and the middle door 1b are opened when passengers get on and off by an operation at the driver's seat 1e, and are closed when traveling. Each device around the driver's seat (A portion in FIG. 1) of the automatic engine stop / start device (hereinafter referred to as “ISS device”) of the present invention is arranged as shown in FIG.
According to FIG. 2, the driver's seat area device 2 of the ISS device indicates that the ISS device is “controlling” or “system abnormal”, “ISS ENG stopped” (ENG: engine), and “ISS” system is operating. Meter cluster 21 provided with a multi-display monitor for displaying that, ISS device main switch 22 for operating / stopping the ISS device on the right side of the handle 26, and the floor of the driver's seat 1e, A foot switch 25 for starting the engine, a brake pedal 24, and an accelerator pedal 23 are provided.

FIG. 3 is a block diagram showing the configuration of the ISS apparatus of the present invention.
Reference numeral 3 denotes an ISS control means (ISS ECU). The ISS ECU 3 includes an ON or OFF signal of the foot switch 25 used when starting the engine 5 that temporarily cancels or automatically stops the operation of the ISS device, and A / T is a neutral position or other gear position signal 50 (range addend signal), an engine stop switch 22 (ISS main switch) signal that is turned on when the ISS device is used and turned off when it is not used The signal 60 from the ISS starter for starting the engine 5, the air pressure sensor 8 for detecting the air pressure of the brake circuit, the signal 41 (not shown) of the vehicle speed sensor for detecting the vehicle stop state, and the like are input.

Reference numeral 6 denotes an engine ECU which is an engine control means for controlling the rotational speed, output, starting and stopping of the engine 5 and the like.
The engine ECU 6 and the ISS ECU 3 are connected by a CAN signal, communicates information on the operation status on the engine 5 side to the ISS ECU 3 side, determines whether to perform idling stop on the ISS ECU 3 side, and the determination result Is communicated to the engine ECU 6 side.
This information is displayed on the meter cluster 21.

FIG. 5 is a block diagram showing a schematic configuration of the brake device 7 in the present embodiment.
In the brake device 7 shown in FIG. 5, a first air pipe 73, which is an air pipe connected to a rear air tank 71, which is an air tank for a rear wheel 1d, and a front air tank 72 for a front wheel 1c are connected. A second air pipe 74, which is an air pipe that has been made, is disposed. A dual brake valve 70 as a brake valve is interposed in the middle of the first and second air ducts 73 and 74, and the brake pedal 24 is connected to the dual brake valve 70. That is, by operating the brake pedal 24 at the driver's seat 1e, the dual brake valve 70 is opened and closed, and the amount of air flow in the first and second air pipes 73 and 74 can be adjusted.

The second air line 74 is further connected to the FW brake booster 83 via the second double check valve 77. Here, the second double check valve 77 enables air to flow from the dual brake valve 70 or the second brake control valve 79 described later to the FW brake booster 83. The FW brake booster 83 is configured to convert air pressure into high hydraulic pressure, and the FW brake booster 83 is connected to each FL brake 832 and FR brake 831 of the front wheel 1c.
Between the dual brake valve 70 and the second double check valve 77, an air pressure sensor is an air pressure detecting means for detecting the air pressure output from the dual brake valve 70 in accordance with the depression amount of the brake pedal 24. 8 is interposed.
The air pressure detection signal of the air pressure sensor 8 is transmitted to the ISS ECU 3 and processed by the ISS ECU 3 to be used for transmitting a stop lamp lighting signal and controlling the engine ECU 6 and the engine 5.

  Similarly, the first air pipe 73 is connected to the RR brake booster 84 and the RL brake booster 85 via the first double check valve 76. Here, the first double check valve 76 enables air to flow from the dual brake valve 70 or the first brake control valve 78 described later in the direction of the RR brake booster 84 and the RL brake booster 85. The RR brake booster 84 and the RL brake booster 85 are connected to the RR brake 841 and the RL brake 851 of the rear wheel 1d.

  Further, a third air pipe 86 is provided between the air tank 71 and the first double check valve 76. The third air line 86 includes a check valve 86a that allows air to flow from the rear air tank 71 toward the first double check valve 76, and a first brake that closes and opens the third air line 86. A control valve 78 is provided, and an orifice 78 a is provided on the upstream side (air tank 71) side of the first brake control valve 78.

  Similarly, a fourth air conduit 87 is provided between the air tank 72 and the second double check valve 77. The fourth air line 87 includes a check valve 87a that allows air to flow from the front air tank 72 toward the second double check valve 77, and a second brake that closes and opens the fourth air line 87. A control valve 79 is provided.

The operation of the brake device according to the embodiment shown in FIG.
First, the operation during normal operation will be described.
When the brake pedal 24 is operated by the driver and the dual brake valve 70 is opened, high pressure air flows from the front air tank 72 through the second air conduit 74, and the dual brake valve 70 and the second double check valve 77 are turned on. Is supplied to the FW brake booster 83, the air pressure is converted into hydraulic pressure in the FW brake booster 83, and high-pressure brake oil is supplied to the FR brake 831 and the FL brake 832 to apply braking force to the front wheels of the bus 1. . Similarly, high-pressure air from the rear air tank 71 flows through the first air conduit 73 and is supplied to the RR brake booster 84 and the RL brake booster 85 via the dual brake valve 70 and the first double check valve 76. In the RR brake booster 84 and the RL brake booster 85, the air pressure is converted into hydraulic pressure, and high-pressure brake oil is supplied to the RR brake 841 and RL brake 851 to apply braking force to the rear wheels of the bus 1.

FIG. 4 shows an example of a characteristic diagram of the air pressure output from the dual brake valve 70 with respect to the depression amount of the brake pedal 24.
The horizontal axis indicates the amount of depression of the brake pedal 24, and the vertical axis indicates the air pressure output from the dual brake valve 70.
The air pressure output from the dual brake valve 70 is an output proportional to the amount of depression of the brake pedal 24.
The air pressure is transmitted to the ISSECU 3 by the air pressure sensor 8, and the ISSECU 3 determines that the air pressure has reached a first threshold value preset as a stop lamp lighting threshold value or a second threshold value set as a predetermined value. .
The first threshold is a state in which the bus 1 can stop on a flat road surface at the initial stage when the air pressure is generated, and the pressure has reached a level that can be detected by the ISS ECU 3 for sending a stop lamp lighting instruction signal. It is.
This is to prevent rear-end collision with the host vehicle by informing the subsequent vehicle that the driver operates the brake pedal 24 at an early stage.
The second threshold is a state where a certain level of pressure has been reached on the road surface with a steep slope (for example, 12% slope or more) that requires the brake pedal 24 to be depressed deeply.

As described above, when the A / T-mounted bus 1 stops, the ISS device operates and instantaneously stops idling.
However, the idling stop is prevented by adjusting the amount of depression of the brake pedal 24 so that the vehicle can start immediately in the case of temporary stop, right turn, left turn or waiting for a pedestrian to cross a pedestrian crossing.
In this case, the air pressure output from the dual brake valve 70 is transmitted to the ISSECU 3 by the air pressure sensor 8 and processed by the ISSECU 3.
In other words, when the driver wants a system that can start immediately (maintaining the idling state), the driver depresses the brake pedal 24 to stop the vehicle at a gentler slope than a flat ground or a steep slope (for example, 12% slope or more). Then, the ISS ECU 3 determines that the air pressure is less than the second threshold, and continuously maintains the idling of the engine 5.
On the other hand, when the bus 1 maintains a relatively long stop such as a stop, a signal wait, or a railroad crossing, the brake pedal 24 is further depressed after the stop (to a point where the vehicle can stop on a road surface with a steep slope, for example, 12% slope or more The ISSECU 3 determines that the air pressure is equal to or higher than the second threshold value, and stops idling.
If the driver wants to be ready to start immediately (maintain idling state) on a steep slope (for example, 12% slope or higher), the driver stops with the foot switch 25 being depressed before stopping. Alternatively, by turning off the ISS device main switch, the ISS ECU 3 can continuously maintain idling of the engine 5 regardless of the state of the second threshold air pressure.

An operation mechanism for continuing and stopping idling by the air pressure sensor 8 will be described with reference to FIG.
FIG. 6A shows a case where idling is continued. At 55, the detected value from the air pressure sensor 8 is less than the second threshold value (first pressure stage), and at 41, detected from the vehicle speed sensor (not shown). When the value is in the stopped state (V1 <1.7 km / h), the main switch 22 of the ISS device is ON (the ISS device is operating), and when these conditions are satisfied (AND), the ISS ECU 3 outputs an idling continuation signal to the engine ECU 6 To do.
FIG. 6B shows a case where idling is stopped. At 55, the detected value from the air pressure sensor 8 is equal to or higher than the second threshold (second pressure stage), and from 41, the vehicle speed sensor (not shown). When the detected value of the vehicle is stopped (V1 <1.7 km / h) and the main switch 22 of the ISS device is ON (the ISS device is operating) and these conditions are satisfied (AND), the ISS ECU 3 sends an idling stop signal to the engine ECU 6. Output to.
In the present embodiment, the air pressure detection is performed by the ISSECU 3 determining the detection value of the air pressure sensor 8, but instead of the air pressure sensor 8, an air pressure switch is used and the air pressure switch is OFF. When the air pressure switch is ON, it can be used as the second threshold value, and the same effect can be obtained.

  By adopting such a configuration, it is possible to continue the engine operation or stop the engine by changing the amount of operation of the brake pedal based on the intention of the driver. Since the engine was stopped at the stop of the car against the intention of the driver, it was possible to start as soon as the pedestrian crossed. Further, since engine stall does not occur on slopes and the like, there is no occurrence of rearward movement of the vehicle, and safe driving with respect to getting on and off of pedestrians and passengers of the own vehicle is improved.

  By performing automatic stop / restart of the engine mounted on the vehicle, the fuel efficiency can be improved and the apparatus can be used for a device that reduces the complexity of the driver's operation.

1 Bus (vehicle)
1b Middle door 2 Around driver's seat 3 ISS ECU (automatic stop / start control means)
5 Engine 6 Engine ECU (Engine control means)
7 Brake device 8 Air pressure sensor (Air pressure detection means)
21 Meter cluster 22 ISS device main switch 24 Brake pedal 25 Foot switch 70 Dual brake valve (brake valve)
71 Rear air tank (air tank)
72 Front air tank (air tank)
73 1st air line (air line)
74 Second air line (air line)
76 First double check valve 77 Second double check valve 83 FW brake booster (brake booster)
84 RR Brake Booster (Brake Booster)
85 RL brake booster (brake booster)

Claims (1)

In an engine automatic stop / start device for automatically stopping or automatically starting an engine mounted on a vehicle,
An air tank mounted on the vehicle for storing compressed air;
A brake booster that converts the compressed air into high-pressure hydraulic pressure and supplies it to the brake;
An air line connecting the air tank and the brake booster;
A brake valve that is provided in the air pipe and outputs compressed air from the air tank at a pressure corresponding to the amount of depression of the brake pedal;
An air pressure detecting means that is disposed between the brake valve and the brake booster in the air line and detects an air pressure output from the brake valve;
Engine control means capable of automatically stopping and automatically starting the engine;
Based on the detected value of the detected air pressure, an engine automatic stop or start control means for outputting an engine automatic stop or automatic start to the engine control means;
A foot switch having a function of temporarily canceling the operation of the automatic stop and start device of the engine,
The automatic stop / start control means outputs a signal for lighting a stop lamp of the vehicle when the air pressure detecting means detects an air pressure equal to or higher than a first threshold, and the foot switch is turned on before the vehicle stops. When stepped on, the engine automatic stop is stopped while the foot switch is stepped on,
When the foot switch is not stepped on and the air pressure detection means detects an air pressure that is greater than the first threshold value and less than a second threshold value , engine operation is continued, and the air pressure detection means is activated by the second threshold value. An engine automatic stop / start device for controlling the engine control means to stop the engine when the above air pressure is detected.

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