JP2000110625A - Engine speed control device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a demand for enhancing a heating performance and a demand for improving the fuel consumption or a demand for lowering vibration and noise, which is contrary to the former demand compatible on a level higher than that of the conventional one, by suitably setting an idling speed in accordance with a condition of an automobile. SOLUTION: This device is composed of a sensor 17 for detecting a parameter relating to a water temperature, a scaling means 9 stages for storing a plurality of different maps in which parameters relating to water temperatures are set in accordance with control values with which the idling speed is controlled, a control means 18 for selecting any one of the maps in accordance with a parameter relating to a water temperature detected by the sensor 17 so as to make reference to thus selected map in order to obtain a control value corresponding to the parameter relating to the water temperature, and a setting means 20 for setting an idling speed in accordance with the control value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an engine speed of an automobile, and more particularly to a device for controlling an idling speed.

[0002]

2. Description of the Related Art When the accelerator pedal is not depressed (idling state), the engine speed is set to the idling speed. Since the throttle valve is closed during idling, idling cannot be maintained unless another mechanism for securing the flow rate of air is provided. Therefore, by providing an idle-up device and controlling the idle-up device, necessary air during idling is secured. As the idle-up device, an ISC (idle speed control) valve provided in a bypass passage communicating between the upstream and the downstream of the throttle valve is usually used.
By opening the ISC valve in the idling state, air can be supplied to the engine via this bypass passage. The idling speed is controlled by the opening of an ISC valve that adjusts the flow rate of air.

[0003] By the way, improvement of fuel efficiency at the time of idling,
Alternatively, from the viewpoint of reducing vibration and noise, it is preferable to set the opening of the ISC valve as small as possible to reduce the idling rotational speed. On the other hand, from the viewpoint of comfort when heating is required, that is, from the viewpoint of improving heating performance, the opening of the ISC valve is set as large as possible,
It is preferable to increase the idling speed. Conventionally, in order to satisfy both of these conflicting demands, an idling rotational speed is set so as not to deteriorate fuel consumption and the like so much and not to decrease heating performance so much.
However, with the need to further improve fuel efficiency and reduce vibration and noise, conventional technologies are limited in meeting these requirements at a higher level without sacrificing heating performance. There is.

[0004]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, an object of the present invention is to improve the heating performance and improve the fuel efficiency by appropriately setting the idling speed according to the situation of the vehicle. It is to satisfy conflicting demands for improvement of vibration or reduction of vibration / noise at a higher level than the prior art.

[0005]

According to a first aspect of the present invention, a first detecting means for detecting a parameter relating to a water temperature, and each map includes a parameter for detecting a parameter relating to a water temperature. One of the maps is selected based on a storage unit that stores a plurality of different maps defined in association with a control value for controlling the rotation speed and a parameter related to the water temperature detected by the first detection unit. Control means for referring to the selected map to determine a control value corresponding to a parameter relating to water temperature,
A control unit for setting the idling speed based on a control value.

According to a second aspect of the present invention, a first detecting means for detecting a parameter relating to a water temperature, a second detecting means for detecting a shift position, and a map for each of which the parameters relating to the water temperature are used for idling. Storage means for storing a plurality of different maps, which are defined in association with a control value for controlling the number of revolutions, and a parameter relating to the water temperature detected by the first detection means and a shift position detected by the second detection means. Control means for selecting one of the maps, referring to the selected map, and obtaining a control value corresponding to the parameter relating to the water temperature, and setting means for setting the idling speed based on the control value. The present invention provides an engine speed control device for an automobile having the following.

In the first and second embodiments, the storage means preferably stores the first map and the second map. Here, the first map defines parameters relating to the water temperature in association with control values for controlling the idling speed. Further, the second map defines a parameter relating to the water temperature in association with a control value for controlling the idling rotational speed, and in at least a part of the parameter relating to the water temperature, the idling rotational speed is lower than the control value of the first map. Has a control value to be set high. In this case, the control unit compares the parameter related to the water temperature detected by the first detection unit with the set value, and selects the first map when the parameter related to the water temperature is equal to or more than the set value, and determines whether the parameter related to the water temperature is If it is smaller than the set value, the second map may be selected.

[0008] The storage means may further store a third map. This third map defines a parameter relating to the water temperature in association with a control value for controlling the idling rotational speed, and in at least a part of the parameter relating to the water temperature, the idling rotational speed is smaller than the control value of the second map. It has a control value that is set high. In this case, when the parameter relating to the water temperature detected by the first detection means has decreased by a predetermined amount or more, or when the increase amount within a predetermined time is equal to or less than a predetermined value, the control means performs the Preferably, the third map is selected.

On the other hand, it is preferable that the setting means is a valve provided in a bypass passage for communicating between the upstream and the downstream of the throttle valve.

[0010] The above-mentioned parameters relating to the water temperature are as follows:
The temperature may be a water temperature or an indoor temperature of an automobile.

The control means may select one of the maps in consideration of the vehicle speed.

[0012]

In the above configuration, the current situation where the car is placed is determined, and if it is determined that high heating performance is required, a map suitable for the situation is applied to increase the idling speed. Promote warm-up. On the other hand, when it is determined that the situation is not such, the control using a different map is performed. By preparing a plurality of different maps in this way and applying a map suitable for the current situation determined from parameters relating to the water temperature, etc., a detailed idling speed suitable for the situation where the car is placed is provided. Control can be performed.

[0013]

FIG. 1 is a schematic diagram showing an example of the configuration of an engine intake system according to the present embodiment. The air sucked from the duct is supplied to the supercharger 2 via the air cleaner 1, the throttle valve 3, and the intake passage 14. The supercharger 2 is, for example, a turbocharger, a supercharger, or the like. When the supercharger 2 is operating, the upstream side of the supercharger 2 is in a negative pressure state (a state lower than the atmospheric pressure), and the downstream side is in a positive pressure state (a state higher than the atmospheric pressure). ing. The downstream side of the supercharger 2 is connected to an intake manifold 6 via an intercooler 7. Intake manifold 6 is connected to engine 11, and engine 11 is connected to exhaust manifold 12. The air that has been pressurized and increased in temperature in the supercharger 2 is cooled by the intercooler 7 and is supplied from the intake manifold 6 to each cylinder in the engine 11.

A bypass passage 4 is provided between the upstream and downstream of the throttle valve 3.
An ISC valve 5 is provided therein. The idle-up device constituted by the bypass passage 4 and the ISC valve 5 is in a state where the accelerator pedal (not shown) is released and the throttle valve 3 is closed (idling state).
By bypassing the throttle valve 3, air is introduced into the intake passage 14.
Pour into Since the flow rate of air can be adjusted by controlling the opening of the ISC valve 5, the idling speed can be set to a desired value.

On the other hand, a bypass passage 8 is provided for communication between the intake manifold 6 and the intake passage 14, and a bypass valve 9 is provided in the bypass passage 8. The bypass valve 9 is opened and closed by a supercharging pressure control valve 10. When the supercharging pressure (positive pressure) generated by the supercharger 2 rises more than necessary, the bypass valve 9 is pushed up by the positive pressure, and the intake manifold 6
The air inside leaks into the bypass passage 8. This allows
The supercharging pressure is prevented from rising more than necessary.

The engine control unit (hereinafter, referred to as ECU) 13 includes an input circuit, an output circuit, a CPU, a memory, and the like. The ECU 13 performs calculations necessary for controlling the engine according to input information from various sensors. In the present embodiment, among the information input to the ECU 13, information from the range detector 15 that detects the shift position of the automatic transmission (AT), the blower fan switch 16, and the water temperature sensor 17 are important. The ECU 13
Based on the calculation result, a control signal for controlling the ISC valve 5, the supercharging pressure control valve 10, the compressor relay 14, and the like is output.

FIG. 2 is a flowchart showing a control procedure of the idling speed. This flowchart is repeatedly executed at a predetermined interval (for example, 10 ms). FIG. 3 is a diagram showing the EC when the flowchart of FIG. 2 is executed.
It is a functional block diagram of U. First, in step 1, the ECU reads necessary sensor values. That is, the water temperature Tw of the radiator is obtained from the sensor signal from the water temperature sensor 17.
And the range from the range detector 15 is specified. In addition, necessary information such as a vehicle speed V obtained from a sensor signal from the vehicle speed sensor is obtained.

Next, it is determined whether or not the ignition switch has been turned (step 2). When this flowchart is executed when the ignition key is turned, the procedure from step 3 is executed. Meanwhile, one end,
After the ignition key is turned, the procedure from step 10 is executed. In an apparatus in which the range in which the ignition key can be turned is only the P range, the determination in this step is based on the premise that the ignition key is in the P range. On the other hand, P range and neutral range (hereinafter, referred to as P range and neutral range)
In a device that can turn the ignition key in either of the N ranges, it is assumed that the ignition key is in the P range or the N range.

When turning the ignition key, step 2
According to this determination, the procedure after step 3 is executed. In this case, the determination unit 18 compares the current water temperature Tw obtained from the signal of the water temperature sensor 17 with a predetermined threshold value (for example, −8 ° C.) read from the memory 19. This threshold is set to an appropriate value because it is a criterion for selecting either the warm-up mode that emphasizes heating performance or the warm-up mode that emphasizes fuel efficiency (or reduction of vibration and noise). It is important to keep it. In this embodiment, the water temperature T
If w is equal to or higher than the threshold value −8 ° C., the first initial mode setting flag FLAG1 is cleared (step 7), and the second
After turning on the initial mode setting flag FLAG2 (step 8), the MID mode is selected as the warm-up mode (step 9). On the other hand, when the water temperature Tw is less than -8 ° C,
After turning on the flag FLAG1 (step 4) and clearing the flag FLAG2 (step 5), the HI mode is selected (step 6).

Initial mode setting flags FLAG1, FLAG
Reference numeral 2 denotes a flag for setting a warm-up mode in a period from when the ignition key is turned to when the vehicle starts running.
When the flag FLAG1 is turned on and the flag FLAG2 is cleared, the HI mode is selected. On the other hand, when the flag FLAG2 is on and the flag FLAG1 is cleared, the MID mode is selected. Initial mode setting flags FLAG1, FL
Since AG2 is a flag for setting the warm-up mode until the start of traveling, both of the two flags are cleared after traveling is started once (that is, when shifting to the D range or the like).

Here, the warm-up mode will be described. The warm-up mode set in this embodiment includes the HI mode, M
ID mode, LOW mode, and D range mode
There is one. FIG. 5 is an example of a map that defines the relationship between the water temperature and the idling speed in each warm-up mode.
In the figure, the HI mode is indicated by a solid line, the MID mode is indicated by a dashed line, the LOW mode is indicated by a dashed line, and the D range mode is indicated by a dashed line. Where D
The range mode is the reverse range (hereinafter referred to as R range)
This is a warm-up mode used when the vehicle is set to the D range or the D range (that is, set to the travel range). The idling speed N is appropriately set in consideration of the balance between creep and braking force. The LOW mode is a warm-up mode for setting a low idling speed in the N range or the P range (that is, the non-traveling range). When this mode, which focuses on setting the idling rotation speed low, is selected, the heating performance itself is sacrificed to some extent, but the fuel consumption can be improved and the vibration and noise can be reduced instead. The LOW mode is, for example,
This is selected when the blower fan is off and is set to the non-running range. The non-traveling range refers to a state in which the shift position of the AT is set to the P range or the N range regardless of whether the vehicle is actually traveling. Therefore, the LOW mode can be selected even during coasting set to the N range. On the other hand, M
The ID mode is a normal warm-up mode when a non-traveling range is set. This is selected when the water temperature is high immediately after the engine is started (for example, −8 ° C. or higher) or when the water temperature is appropriately rising. Further, the HI mode is a warm-up priority mode when the non-travel range is set, and is used when the water temperature is low immediately after the engine is started (for example, below -8 ° C) or when the rate of increase of the water temperature is low (at extremely low temperatures). Selected. When this mode is selected with a focus on setting a high idling rotation speed, fuel efficiency, vibration, or noise is sacrificed to some extent, but heating performance can be improved instead.

The idling rotational speed N can be obtained as a control value corresponding to the detected water temperature Tw with reference to the warm-up map shown in FIG. For example, when the selected warm-up mode is the HI mode, when the water temperature Tw is 0 degrees, the idling rotational speed N to be set is about 2300 rpm. Further, as can be seen from FIG. 5, each warm-up map has a different pattern. Each warm-up map is D
Range mode, LOW mode, MID mode, and H
The idling rotational speed N tends to be set higher in the order of the I mode (for example, see a water temperature around 40 ° C.). In the HI mode, the idling speed N is set higher than in other warm-up modes. Thereby, warming-up can be promoted more than in other warming-up modes, so that heating performance can be improved. On the other hand, in the LOW mode, the idling rotational speed N is set lower than in the warm-up mode excluding the D range mode, so that fuel efficiency and the like can be prioritized. Note that each warm-up pattern includes the D range mode, the LOW mode, and the MI range in all temperature ranges of the water temperature Tw.
It is not necessary to increase the idling rotational speed N in the order of the D mode and the HI mode, and it is sufficient that the relationship is at least in a certain temperature range. As can be seen from FIG. 5, when the engine is sufficiently operated and the water temperature Tw is sufficiently raised (for example, about 80 ° C. or higher), the idling rotational speeds N obtained from all the warm-up modes have the same value (about 7).
00 rpm). In such a state where the temperature is sufficiently increased, it is not necessary to set the idling rotational speed N higher than in the other modes, even in the mode in which the warm-up is prioritized. Conversely, even in a state where the water temperature Tw is low (for example, in a temperature range of about −20 ° C. or less), the idling speed N in the warm-up mode excluding the D range mode shows the same value. This is because when the outside air is extremely low, such as in a cold region,
This is because, even in the HI mode, warming-up must be given the highest priority as in the HI mode.

According to step 6 or step 9, HI
When either one of the warm-up mode and the MID mode is selected, the engine speed control in each mode is executed as a subroutine. Judgment unit 1
8 refers to the warm-up map stored in the memory 19,
The control value corresponding to the water temperature Tw is read. And setting section 2
0 controls the opening and closing of the ISC valve 5 according to this control value. As the opening θisc of the ISC valve 5 increases,
The idling rotation speed N can be increased. When the idling speed N is set only by adjusting the opening θisc of the ISC valve 5 (that is, when the idling speed N is controlled only by the opening θisc of the ISC valve 5), the water temperature Tw and Opening θis of ISC valve 5
A warm-up map that defines the relationship with c (control value) may be used. It is to be noted that a bypass passage connecting the upstream and downstream of the throttle valve is provided separately from the bypass passage 4, and a FICD (fast idle control device) valve (not shown) is provided in the bypass passage. In the configuration, the idling speed N can be controlled by adjusting the opening degree of the FICD valve. In this case, the setting unit 20 sets the F based on the warm-up map.
ICD valve opening (or ISC valve 5 and FICD
Control the opening of both valves).

At the time of the next execution of the flowchart after 10 ms has elapsed, the ignition key has already been turned, so the determination in step 2 is NO. Therefore,
Proceed to step 10. That is, the determination in step 2 becomes Yes only when the ignition key is turned, and thereafter, the process proceeds to step 10. In step 10, it is determined whether the current range is in the P range or the N range (step 10). Immediately after turning the ignition key, the range is the P range (or the N range). If the initial mode setting flag FLAG1 is turned on in step 4 at the time of execution of the previous flowchart, the HI mode is continuously selected by the determination in step 11 (step 6). On the other hand, at the time of execution of the previous flowchart, the initial mode setting flag FLAG
When 2 is on, the MID mode is continuously selected according to the determinations in steps 11 and 12 (step 9). Until shifting to D range (or R range)
The above procedure is repeatedly executed, and the HI mode or the MI mode
Engine speed control in the D mode is performed.

When the vehicle starts running after shifting to the D range, the procedure from step 13 is performed according to the determination at step 10. If the car is in a running state (including when stopped in the D range), the D range mode is selected (step 13), and the initial mode setting flag FLAG1 is set.
, FLAG2 is cleared (step 14), and the process proceeds to return. Since this series of procedures is repeatedly performed while the engine is set to the D range, the control of the idling speed N based on the warm-up map in the D range mode is continuously performed.

After that, when shifting to the N range or the P range (non-traveling range), the flag FLAG
Since 1 and FLAG2 have been cleared, the process proceeds from step 10 to step 15 via steps 11 and 12. The determination unit 18 determines whether the water temperature Tw is “extremely low temperature” (Step 15). Here, “extremely low temperature” refers to a state in which the water temperature does not rise appropriately. In the present embodiment, as an example, it is determined that the temperature is extremely low when any of the following conditions is satisfied.

(Example of extremely low temperature judgment) (a) When the water temperature Tw is 65 ° C. or less and the water temperature rise for 2 minutes (a value corresponding to the set value CT1) is 2 ° C. or less (b) Maximum after starting the engine 5 ° C or higher than water temperature Tw
(However, the upper limit of the maximum water temperature is 79 ° C)

For example, when the outside air temperature is low in a cold region and the water temperature Tw rises low or decreases, it is necessary to increase the idling speed N to promote warm air. Therefore, if the above low temperature condition is met, the HI mode giving priority to warm air is selected (step 6). The rate of increase of the water temperature Tw is calculated by the calculation unit 21. The time is counted by a counter 22 in the ECU.

On the other hand, if the above cryogenic condition is not met, the routine proceeds to step 16. If the water temperature Tw is equal to or higher than 10 ° C., the LOW mode is selected (step 17), and the flags FLAG1 and FLAG2 are cleared (step 18). Thus, the control of the idling rotational speed N based on the LOW mode is executed. On the other hand, if the water temperature Tw is lower than 10 ° C., the MID mode is selected (step 9).

As described above, when the warm-up mode is selected according to the flowchart shown in FIG. 2, the idling speed N is controlled based on the map of the selected warm-up mode. The warm-up mode is appropriately switched according to a change in the state of the water temperature. For example, when control based on the HI mode is performed in an extremely low temperature state, if the water temperature Tw rises and does not meet the extremely low temperature condition, control may be shifted to the MID mode. Even when the control in the MID mode is performed, the control is switched to the control in the LOW mode when the water temperature Tw becomes 10 ° C. or more. further,
Even when the control is performed in the LOW mode, the MID mode, or the HI mode, the mode is switched to the D range mode when shifting to the D range or the R range.

Next, a modification of the above embodiment will be described. FIG. 4 is a diagram showing switching of the warm-up mode during traveling and conditions for switching. The switching condition of the warm-up mode is basically in accordance with the condition of the flowchart of FIG. 2, but takes into account the actual use condition and controllability. That is, when the blower fan switch 16 is off, the LOW mode is basically selected, and when the blower fan switch 16 is on, the MID mode and the HI mode are selected. When the blower fan switch 16 is off, it can be determined that there is no need to heat the interior of the vehicle, so that it is not necessary to consider the warm-up priority mode. Further, in consideration of the actual use situation, the setting is made so that the mode is not switched from the HI mode to the MID mode. Note that the switching conditions shown here are examples, and the present invention is not limited to these. Therefore, for example, the switching condition from the HI mode to the MID mode is changed to non-cryogenic temperature,
As with the switching condition from MID mode to LOW mode,
"The case where the water temperature Temp becomes 10 ° C. or more" may be adopted.

As described above, in the present embodiment, an appropriate warm-up mode is selected based on the shift position and the water temperature, and the warm-up mode is switched in accordance with a change in running conditions. That is, in an environment where importance is placed on the heating performance, the idling speed is increased to promote warm-up. On the other hand, in an environment where the heating performance does not need to be so important, the idling speed is lowered to improve the fuel efficiency or reduce noise and vibration. As described above, since the idling rotation speed suitable for the driving situation is set, it is possible to achieve both improvement of the heating performance and improvement of the fuel efficiency. In addition, since the control of the idling rotational speed as described above does not need to provide a new sensor or a component, there is also an effect that the existing device can easily execute the control without increasing the cost.

In this embodiment, the case where four warm-up modes are provided has been described as an example. However, the present invention can be applied to the case where more warm-up modes are provided. is there.

In selecting the warm-up mode, it is preferable to consider the vehicle speed. For example, a condition may be set so that, when the MID mode is selected and the vehicle speed is 10 km / h and the blower fan switch 16 is turned off, the mode shifts to the LOW mode. Further, in a state where the HI mode is selected, when the vehicle speed is 10 km / h and the blower fan switch 16 is turned off, the setting may be made to shift to the LOW mode. By selecting the warm-up mode in consideration of the vehicle speed in this way, it is possible to perform control more suitable for actual traveling.

In the above embodiment, the warming-up mode is switched based on the water temperature. However, the present invention can be applied to a case where another parameter that changes according to the water temperature is used. Can be. As such a parameter relating to the water temperature, for example, the indoor temperature of an automobile can be used. Since the water temperature can be estimated based on the room temperature, it can be determined whether the environment where the improvement of the heating performance should be prioritized or not.

Further, in the above embodiment, the automatic transmission (A
T), the present invention is applied to a manual transmission (M
It is also possible to apply to T). In this case, instead of the non-traveling range (P range or N range) in the AT, it is only necessary to determine whether or not the gear is in a neutral state as the shift position determination, and set the warm-up mode based on the result. . By changing the warm-up mode based on the water temperature while the gear is in neutral, the idling speed can be appropriately controlled.

Further, in the above-described embodiment, an engine having a supercharger has been described. However, it is needless to say that the present invention is not limited to this and can be applied to an engine having no supercharger.

[0038]

As described above, according to the present invention, the running condition of the automobile is estimated based on the parameter relating to the water temperature, and the idling speed during the warm-up operation is finely controlled.
As a result, it is possible to achieve both higher heating performance and reduced vibration and noise or improved fuel efficiency at a higher level.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an example of a brake device according to an embodiment.

FIG. 2 is a flowchart showing a control procedure of an idling rotation speed;

FIG. 3 is a functional block diagram of an ECU when executing the flowchart of FIG. 2;

FIG. 4 is a diagram showing switching between warm-up modes during traveling and conditions for switching.

FIG. 5 is an example of a map defining a relationship between a water temperature and an idling speed in each warm-up mode.

[Explanation of symbols]

1 air cleaner, 2 supercharger, 3 throttle valve, 4 bypass passage, 5 ISC valve, 6 intake manifold, 7 intercooler, 8 bypass passage, 9 bypass valve, 10 boost pressure control valve,
11 engine, 12 exhaust manifold,
13 ECU, 14 intake passage, 15 range detector,
16 Blower fan switch, 17 Water temperature sensor, 18
Judgment unit, 19 memory, 20 setting unit, 21 operation unit, 22 counter

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tomohiro Sakurai 1-7-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Fuji Heavy Industries Ltd. F-term (reference) 3G084 BA03 BA06 BA36 CA03 DA02 DA39 EB08 FA05 FA06 FA20 FA33 FA36 3G093 AA05 BA19 BA32 BA33 CA04 DA01 DA05 DA12 DB05 DB11 DB25 EA07

Claims (8)

[Claims] 1. A first detecting means for detecting a parameter relating to a water temperature, and each map includes a parameter relating to the water temperature,
A storage unit that stores a plurality of different maps defined in association with a control value for controlling an idling rotation speed, and any one of the maps based on a parameter relating to the water temperature detected by the first detection unit. A control unit that selects and refers to the selected map to obtain the control value corresponding to the parameter relating to the water temperature; anda setting unit that sets the idling speed based on the control value. Characteristic control device for engine speed of automobile. 2. A first detecting means for detecting a parameter relating to water temperature; a second detecting means for detecting a shift position;
Storage means for storing a plurality of different maps defined in association with a control value for controlling the idling rotational speed; parameters relating to the water temperature detected by the first detection means and detected by the second detection means Control means for selecting one of the maps based on the shift position, referring to the selected map, and obtaining the control value corresponding to the parameter relating to the water temperature, based on the control value, Setting means for setting the idling rotational speed, the rotational speed control device for an automobile engine. 3. A storage device comprising: a first map defining parameters relating to the water temperature in association with the control value; defining a parameter relating to the water temperature in association with the control value; A second map having the control value such that the idling speed is set higher than the control value of the first map is stored in at least a part of the area. 3. The apparatus for controlling the number of revolutions of an engine of an automobile according to claim 1. 4. The control means compares a parameter relating to the water temperature detected by the first detection means with a set value. If the parameter relating to the water temperature is equal to or higher than the set value, the first map is displayed. 4. The control device according to claim 3, wherein the second map is selected when the parameter relating to the water temperature is smaller than the set value. 5. 5. The storage means defines a parameter relating to the water temperature in association with the control value, and in at least a part of the parameter relating to the water temperature, the idling is performed more than the control value of the second map. A third map having the control value such that the rotation speed is set to be high is stored, and the control unit determines that the parameter relating to the water temperature detected by the first detection unit has decreased to a predetermined amount or more. 4. The control device according to claim 3, wherein the third map is selected when an increase amount within a predetermined time is equal to or less than a predetermined value. 6. The control of the engine speed of an automobile according to claim 1, wherein said setting means is a valve provided in a bypass passage communicating between an upstream and a downstream of the throttle valve. apparatus. 7. The control device according to claim 1, wherein the parameter relating to the water temperature is a water temperature or an indoor temperature of the vehicle. 8. The control apparatus according to claim 1, wherein the control means selects one of the maps in consideration of a vehicle speed.