JP5759726B2 - Fan clutch control method and apparatus - Google Patents

Description

  The present invention relates to a fan clutch control method and apparatus.

  The cooling fan attached to the vehicle engine plays a role of forcing the outside air through the radiator to help dissipate the coolant that is the cooling medium and preventing overheating of the engine that causes knocking and poor lubrication. When the vehicle is running at a high speed where a sufficient amount of air can be expected, the engine output is lost as much as the cooling fan is driven, resulting in a deterioration in fuel consumption.

  Therefore, an electronically controlled fan clutch is interposed between the crankshaft of the engine and the cooling fan, and the fan clutch is disengaged whenever fan cooling is not required based on the vehicle operating conditions, thereby reducing the rotational energy consumption of the cooling fan as much as possible. Proposals to reduce the number have been made (for example, see Patent Document 1).

  There are two types of electronically controlled fan clutches that are in contact when energized and those that are disconnected when energized. In large transport vehicles such as trucks, Therefore, in order to prevent a situation in which the cooling fan does not rotate even if a malfunction occurs in the electric system, a fan clutch that is in a disconnected state when energized is generally employed.

JP 2005-3131 A

  In recent years, however, an idle stop system has been adopted in which the engine is automatically stopped for a short period of time when the vehicle is stopped due to a signal or the like to reduce exhaust gas emissions. In a large transport vehicle employing such an idle stop system, if the engine is stopped during the idle stop, the energization to the fan clutch is stopped and the fan clutch is brought into a contact state, and the engine after the idle stop is completed. The fan clutch rotates with the engine at the time of restart, and the engine restart torque increases, and the improvement in fuel efficiency due to idle stop is reduced by the deterioration of fuel efficiency at restart, and the noise during restart increases. The problem was invited.

  The present invention has been made in view of such circumstances, and an object of the present invention is to improve fuel efficiency and reduce noise by preventing the fan clutch from rotating with the engine when the engine is restarted after the end of idle stop.

According to the present invention, an electronically controlled fan clutch that is turned off when energized is interposed between an engine of a vehicle that employs an idle stop system and a cooling fan, and the fan clutch is energized and turned off when not needed to improve fuel efficiency. The fan clutch control method is designed so as to energize the fan clutch when the idle stop is performed and keep the fan clutch in a disconnected state, while the transition to the complete stop is confirmed during the idle stop. This is characterized in that the energization of is stopped .

  Thus, in this way, when the vehicle stops due to a signal waiting, etc., even if an idle stop is performed and the engine stops, the fan clutch is energized and the fan clutch is held in a disconnected state. As a result, the fan clutch does not rotate with the engine when the engine is restarted after the end of the idle stop. As a result, the engine restart torque is reduced and the improvement in fuel consumption due to the idle stop is not reduced. Will be kept small.

Furthermore, in the present invention, since the energization to the fan clutch is stopped when the transition to the complete stop is confirmed during the idle stop, the energization to the fan clutch is also performed after the transition from the idle stop to the complete stop. It is possible to avoid a situation in which wasteful power is consumed due to continued operation.

  In the present invention, it is preferable to return to the intermittent control for improving the normal fuel consumption after at least one of the elapse of the predetermined time and the increase of the vehicle speed more than the predetermined is confirmed at the end of the idle stop. By doing so, it is possible to avoid a situation in which the fan clutch is engaged in a state of insufficient torque where the engine speed has not yet sufficiently increased.

Furthermore, in carrying out the method of the present invention more specifically, for example, an electronically controlled fan clutch that is turned off when energized is interposed between an engine of a vehicle that employs an idle stop system and a cooling fan, A fan clutch control device designed to improve fuel efficiency by energizing and disconnecting the fan clutch when it is not needed. The electronically controlled fan controller that performs intermittent control of the cooling fan is connected to the idle stop controller from the idle stop controller. Input and energizing the fan clutch when the idle stop is performed to keep the fan clutch in a disconnected state, while the transition from the idle stop to the complete stop is confirmed based on the idle stop determination information from the idle stop controller structure as sometimes to stop the power supply to the fan clutch Then good.

In addition, regarding to such fan clutch control device, the idle at least one of a predetermined time has elapsed during the idle stop is terminated in accordance with the idle stop determination information and increase of more than a predetermined vehicle speed from the stop controller is confirmed The electronically controlled fan controller may be configured to return to the intermittent control for improving the normal fuel consumption.

  According to the fan clutch control method and apparatus of the present invention, the following various excellent effects can be obtained.

(I) According to the first and third aspects of the present invention, when the vehicle stops due to a signal or the like, even if the engine is stopped due to idling stop, Since the fan clutch can be held in the disengaged state, fuel consumption can be improved and noise can be reduced by preventing the fan clutch from rotating with the engine when the engine is restarted after the end of idle stop.

(II) According to the first and third aspects of the present invention, a situation in which energization of the fan clutch is continued and wasteful power is consumed even after the transition from the idle stop to the complete stop is performed. It can be avoided.

(III) According to the second and fourth aspects of the present invention, it is possible to avoid a situation in which the fan clutch is engaged in a state of insufficient torque where the engine speed has not yet sufficiently increased. Can do.

It is the schematic which shows an example of the form which implements this invention. It is a flowchart which shows the control procedure at the time of an idle stop start. It is a flowchart which shows the control procedure at the time of completion | finish of an idle stop. It is a flowchart which shows an example of the determination format of an idle stop.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an example of a specific form for carrying out the present invention. An engine 1 is equipped with a cooling fan 3 via an electronically controlled fan clutch 2, and the fan clutch 2 is electronically controlled. Intermittent control is performed based on a control signal 4 a from the control fan controller 4.

  Here, the electronic control fan controller 4 is supplied with a detection signal 5a from a temperature sensor 5 which is provided in a thermo case or the like and detects the temperature of the coolant. When the current coolant temperature exceeds a predetermined allowable range based on the signal 5a, a control signal 4a for connecting the fan clutch 2 is output, and when the current coolant temperature falls below the predetermined allowable range, A control signal 4a for disengaging the clutch 2 is output.

  In addition to the radiator for cooling the coolant in the air, the front surface of the cooling fan 3 is air-cooled with an intercooler for air-cooling the intake air heated by the turbocharger and heated, and a gas-phase cooling medium of the air conditioner. Since an air conditioner condenser or the like for restoring the liquid phase is also arranged, a detection signal 6a from the temperature sensor 6 for detecting the intake air temperature of the intercooler, an on / off signal 7a from the switch 7 of the air conditioner, etc. are also input. Even if the current coolant temperature is below the predetermined allowable range, the control signal 4a for connecting the fan clutch 2 is output when the intake air temperature is above the predetermined allowable range or when the air conditioner is operating. You may be made to do.

  At this time, in this embodiment, not only the fan clutch 2 is simply disconnected when not needed, but also when the fan clutch 2 is connected, the required fan rotational speed is precisely calculated to control the rotational speed of the fan clutch 2. The detection signal 2a of the rotational speed of the fan clutch 2 detected in the fan clutch 2 is fed back to the electronically controlled fan controller 4.

  In addition to the normal intermittent control for improving the fuel consumption by disconnecting the fan clutch 2 when it is unnecessary, in the case of this embodiment, an electronically controlled fan controller 4 that performs the intermittent control of the cooling fan 3 is provided. The idle stop determination information 8a is input from the idle stop controller 8 and the fan clutch 2 is energized to hold the fan clutch 2 in the disengaged state when the idle stop is performed.

  That is, as shown in FIG. 2, when the start of idling stop is input from the idling stop controller 8 as the idling stop determination information 8a, the process of calculating the target fan speed is omitted immediately. Forced off is determined, and a control signal 4a for energizing the fan clutch 2 and holding the fan clutch 2 in a disengaged state is output. In this case, the operation control of the fan clutch 2 in FIG. 2 is to maintain the disengaged state of the fan clutch 2, and the actual fan speed detected at this time is zero.

  However, when the transition from the idle stop to the complete stop is confirmed by an operation such as removing the seat belt or opening the door during the idle stop based on the idle stop determination information 8a from the idle stop controller 8, the fan clutch 2 Stop energizing the unit.

  As shown in FIG. 3, when the end of idle stop is input as the idle stop determination information 8a from the idle stop controller 8, for example, the elapse of a predetermined time from the end of the idle stop and a predetermined vehicle speed or more. After confirming at least one of the rises, the control returns to the intermittent control for improving the normal fuel consumption.

  It should be noted that a known technique that has already been put into practical use may be applied to the idle stop determination format in the idle stop controller 8. For example, as shown in the flowchart of FIG. Of course, the determination format is not necessarily limited to that shown in FIG.

  Thus, in this way, when the vehicle stops due to a signal or the like, even if the idle stop is performed and the engine 1 is stopped, the fan clutch 2 is energized and the fan clutch 2 is disconnected. As a result, the fan clutch 2 does not rotate with the engine 1 when the engine is restarted after the end of the idle stop. As a result, the restart torque of the engine 1 is reduced and the improvement in fuel consumption due to the idle stop is not reduced. At the same time, the noise at the time of restart is also suppressed to a small level, and it is possible to realize further improvement in fuel consumption and noise reduction.

  Further, in the present embodiment, since the energization to the fan clutch 2 is stopped when the transition to the complete stop is confirmed during the idle stop, the fan clutch 2 is also maintained after the transition from the idle stop to the complete stop. It is possible to avoid a situation in which useless power is consumed by energizing the battery.

  Further, since at least one of the elapse of the predetermined time and the increase of the vehicle speed more than a predetermined value is confirmed at the end of the idle stop, the engine 1 is returned to the intermittent control for improving the fuel efficiency. It is possible to avoid a situation in which the fan clutch 2 is connected in a state of insufficient torque that has not yet sufficiently increased.

  The fan clutch control method and apparatus of the present invention is not particularly limited to the above-described embodiment, but is a control type related to normal intermittent control in which the fan clutch is disconnected when not needed to improve fuel efficiency. Of course, a format other than those exemplified may be adopted, and other modifications may be made without departing from the scope of the present invention.

1 Engine 2 Fan clutch 3 Cooling fan 4 Electronically controlled fan controller 4a Control signal 8 Idle stop controller 8a Judgment information

Claims (4)

An electronically controlled fan clutch that is turned off when energized is interposed between the engine of the vehicle that uses the idle stop system and the cooling fan, and the fan clutch is energized and turned off when not needed to improve fuel efficiency. A fan clutch control method that energizes the fan clutch when the idle stop is performed and keeps the fan clutch in a disengaged state, while energizing the fan clutch when the transition to the complete stop is confirmed during the idle stop. A fan clutch control method characterized by stopping . 2. The fan clutch control according to claim 1 , wherein at the end of the idle stop, at least one of the elapse of a predetermined time and the increase of the vehicle speed more than a predetermined is confirmed, and then the fan clutch control returns to the intermittent control for improving the normal fuel consumption. Method. An electronically controlled fan clutch that is turned off when energized is interposed between the engine of the vehicle that uses the idle stop system and the cooling fan, and the fan clutch is energized and turned off when not needed to improve fuel efficiency. An electronically controlled fan controller for performing intermittent control of a cooling fan, which is a fan clutch control device, inputs idle stop determination information from an idle stop controller and energizes the fan clutch when the idle stop is performed. Is configured to stop energization of the fan clutch when the transition from the idle stop to the complete stop is confirmed based on the idle stop determination information from the idle stop controller. Fan clutch control device. Based on the idle stop determination information from the idle stop controller, at the end of the idle stop, at least one of the elapse of a predetermined time and the increase of the vehicle speed more than a predetermined is confirmed, and then the control returns to the intermittent control for improving the normal fuel consumption. 4. The fan clutch control device according to claim 3 , wherein an electronically controlled fan controller is configured.

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