Automotive Air Conditioner Control Device

[0015] Embodiments of the present invention are described below with reference to the accompanying drawings.

[0016] Figure 1 to Figure 5 Embodiments of the invention are shown. like figure 2 As shown in , the vehicle air conditioner control device according to this embodiment includes: an "input" unit that outputs various detection signals to the control section 2 (also referred to as "ECM"); a "calculation" unit that includes The control section 2, to which various detection signals from the "input" unit are input, and the "output" unit, to which control signals from the "calculation" unit are input. The vehicular air conditioner control device 1 further includes: a creep torque generating portion 3 that generates a driving torque for moving the vehicle even when the internal combustion engine (not shown) is in an idle state; an air conditioner 4, It is driven by the power generated from the internal combustion engine; and the air conditioner control device 5 which controls the operation state of the air conditioner 4 .

[0017] The vehicle air conditioner control device 1 further includes a brake negative pressure detection unit 6 for detecting the negative pressure amount of the brake. When the amount of brake negative pressure detected by the brake negative pressure detecting portion 6 is lower than a predetermined value, and the creep torque generating portion 3 generates driving torque to start the vehicle to move by the generated driving torque, the air conditioner control device 5 Stop the air conditioner 4.

[0018] Specifically, as figure 2 As shown in , the “input” unit of the vehicle air conditioner control device 1 includes an accelerator opening sensor 7 , a wheel speed sensor 8 , an air conditioner switch 9 , and a brake negative pressure detection unit 6 . The detection signal from the accelerator opening sensor 7 is used to monitor whether an accelerator pedal (not shown) has been operated. The detection signal from the wheel speed sensor 8 is converted into a vehicle speed, which is then used to judge whether the vehicle has moved. The detection signal from the air conditioner switch 9 is used to monitor the A/C compressor drive request from the user. The brake negative pressure detection unit 6 includes at least one of a brake negative pressure switch 10 and a brake negative pressure sensor 11 . The detection signal from the brake negative pressure switch 10 or the brake negative pressure sensor 11 as the brake negative pressure detection unit 6 is used to monitor the brake negative pressure.

[0019] The “calculation” unit of the vehicle air conditioner control device 1 includes a control unit 2 . The control unit 2 includes a creep torque generating unit 3 , an air conditioner control device 5 , and a timer 12 .

[0020] The "output" unit of the vehicle air conditioner control device 1 has an air conditioner 4 having an A/C compressor 13 . In the vehicle air conditioner control device 1 , the control calculation is performed by the control section 2 , and an on/off control signal is output to the A/C compressor 13 .

[0021] Therefore, even in a traveling state that occurs during traveling in a traffic jam or the like, for example, a state in which the vehicle is driven only by the creep torque and the vehicle is stopped by depressing the brake pedal is repeated, the vehicle air conditioner control device 1 The brake negative pressure amount for assisting the driver's brake operating force can be obtained.

[0022] The vehicle air conditioner control device 1 is configured to stop the air conditioner 4 for a set period of time. like figure 2 As shown in the figure, the control unit 2 of the vehicle air conditioner control device 1 has a timer 12 . The control unit 2 performs control to continue the stopped state of the air conditioner 4 for a set period of time based on a signal from the timer 12 . Therefore, once the air conditioner 4 is stopped, the stopped state of the air conditioner 4 is maintained for at least a set time, so that the brake negative pressure amount can be sufficiently obtained.

[0023] will describe image 3 The control logic shown in . suppose when image 3 When the conditions shown in are satisfied, the stop condition of the air conditioner 4 is satisfied. suppose when image 3 When the conditions shown in are not satisfied, the stop condition of the air conditioner 4 is not satisfied. First, when the brake negative pressure sensor 11 is provided in the vehicle air conditioner control device 1, it is determined in the first AND gate AND1: (1) Whether a constant (brake negative pressure switch 10 or brake negative pressure sensor 11) is selected or not (2) Whether the brake negative pressure sensor 11 is normal; (3) Whether the brake negative pressure Bp is lower than the brake negative pressure insufficient judgment pressure (the brake negative pressure insufficient judgment pressure + the brake negative pressure insufficient judgment pressure hysteresis amount). When the vehicle air conditioner control device 1 is provided with a brake negative pressure switch 10, it is determined in the second AND gate AND2: (1) whether the selection constant is 1; (2) whether the brake negative pressure switch 10 is normal; and ( 3) Whether the brake negative pressure switch 10 is "on" (indicating no negative pressure). In a modified example to be described later, if the estimated brake negative pressure application condition is considered, it is determined in the third AND gate AND3 whether: (1) whether the estimated brake negative pressure application condition is satisfied; and (2) the estimated brake negative pressure application condition Whether or not the pressure PbID is lower than the brake negative pressure shortage judgment estimated negative pressure. The first OR gate OR1 judges whether any one of the first to third AND gates AND1 to AND3 is satisfied. After the judgment in the first OR gate OR1, it is judged in the fourth AND gate AND4 whether or not the condition 1 is satisfied. Condition 1 includes: (1) whether the previous vehicle speed Vs is equal to or lower than the vehicle speed at which the crawling start is judged; (2) whether the current vehicle speed Vs is higher than the vehicle speed at which the crawling start is judged; and (3) whether the idle switch is "on" ( That is, whether the accelerator opening is 0%). Meanwhile, the vehicle creep start is determined by setting a minimum value (vehicle speed at which the creep start is determined) and comparing the vehicle speed Vs with the set minimum value. After the judgment in the fourth AND gate AND4, the judgment is made in the second OR gate OR2. The second OR gate OR2 judges any of the following: (1) Whether condition 1 is satisfied in the fourth AND gate AND4; time (stop hold time).

[0024] Here, the main points of the control logic are described supplementally.

[0025] 1. When it is detected that the vehicle starts to crawl under the condition of insufficient brake negative pressure, the air conditioner 4 is stopped (turned off). Since the air conditioner 4 is turned off (power is sent back to the engine) when the vehicle starts to crawl, sufficient brake negative pressure can be obtained for the next vehicle deceleration (to stop the vehicle). Specifically, in the case where the accelerator is not operated (and there are only creep and brake operation), such as during driving in a traffic jam, it is possible to prevent the brake pedal from being hard due to insufficient brake negative pressure. Insufficiency of the brake negative pressure is detected by the brake negative pressure switch 10 or the brake negative pressure sensor 11 as the brake negative pressure detection unit 6 . The start of the vehicle creep is detected by the detection signal from the accelerator opening sensor 7 indicating that the accelerator is turned off and the change between the previous vehicle speed value and the current vehicle speed value. For example, if the vehicle speed value changes from the previous 0 km/h to the current 1 km/h while the accelerator is turned off, it is detected that the vehicle starts crawling.

[0026] 2. The air conditioner 4 is kept in a stopped state (off state) within a set period. Since the time required to obtain sufficient brake negative pressure is appropriately reflected in the stopped state of the air conditioner 4 , it is possible to prevent control oscillation from occurring and to prevent the failure of obtaining the negative pressure. Since there is a time lag in obtaining the brake negative pressure, the A/C compressor 13 needs to be turned off within a predetermined time. Furthermore, since the A/C compressor 13 is turned off for a certain time, the balance between the air conditioning performance and the brake performance can be controlled.

[0027] 3. After the set time elapses, the shut-off control of the air conditioner 4 ends. As described above, since the A/C compressor 13 is in the OFF state for a certain time, and thus the air conditioner 4 is in the OFF state for the certain time, the balance between the air conditioning performance and the brake performance can be controlled .

[0028] Next, refer to figure 1 The operation is described in the control flowchart of the vehicle air conditioner control device 1 shown in .

[0029] When the control routine for judging that the brake negative pressure of the vehicle air conditioner control device 1 is insufficient is started ( 101 ), the routine proceeds to a judgment ( 102 ) whether the selection constant is “0 (zero)”. If the result of the judgment (102) is YES, the routine proceeds to the judgment (103) whether the brake negative pressure sensor 11 is normal. When it is judged ( 102 ) whether the selection constant is "0", if the result of the judgment ( 102 ) is "No", the routine proceeds to judge ( 104 ) whether the brake negative pressure switch 10 is normal. When judging ( 103 ) whether the brake negative pressure sensor 11 is normal, if the result of the judgment ( 103 ) is YES, the routine proceeds to judging ( 105 ) whether the brake negative pressure Bp is lower than the brake negative pressure insufficient judgment pressure (whether or not Brake negative pressure < brake negative pressure insufficient judgment pressure). At this time, once the brake negative pressure becomes lower than the brake negative pressure insufficiency determination value, it is determined that the brake negative pressure Bp is lower than the brake negative pressure insufficiency determination pressure until the brake negative pressure exceeds the brake negative pressure insufficiency determination negative pressure and Insufficient brake negative pressure judges the sum of pressure lag. If the result of judging ( 103 ) whether the brake negative pressure sensor 11 is normal or not is NO, the routine proceeds to the judgment ( 106 ) whether the estimated brake negative pressure PbID is lower than the brake negative pressure insufficient judgment estimated negative pressure (whether PbID < brake Insufficient negative pressure to judge the estimated negative pressure). When judging (105) whether the brake negative pressure Bp is lower than the brake negative pressure insufficient judgment pressure (whether the brake negative pressure Bp

[0030] will refer to Figure 4 The control flow diagram for Condition 1 shown in describes the operation.

[0031] When the control routine of Condition 1 starts ( 201 ), the routine proceeds to a judgment ( 202 ) whether or not there is no brake negative pressure. If the result of the judgment (202) is "NO" (ie, there is a brake negative pressure), the routine proceeds to the process of judging that the condition 1 is not satisfied (203), and then proceeds to the end of the control routine of the condition 1 (208) . If the result of the judgment (202) whether there is no brake negative pressure is YES (ie, there is no brake negative pressure), the routine proceeds to a judgment (204) whether the previous vehicle speed is lower than the vehicle speed (km/km/h) at which the crawling start is judged. h) (Whether the previous vehicle speed Vs≤the vehicle speed at which the crawling starts is judged). When judging ( 204 ) whether the previous vehicle speed is lower than the vehicle speed (km/h) for judging the start of crawling (whether the previous vehicle speed Vs ≤ the vehicle speed for judging the start of crawling), if the result of the judgment ( 204 ) is “No”, the The routine proceeds to processing where it is determined that condition 1 is not satisfied ( 203 ), and then proceeds to the end of the control routine of condition 1 ( 208 ). If the result of the judgment (204) is YES, the routine proceeds to a judgment (205) whether the current vehicle speed exceeds the vehicle speed (km/h) at which the crawling start is judged (current vehicle speed Vs>the vehicle speed at which the crawling start is judged). When judging ( 205 ) whether the current vehicle speed exceeds the vehicle speed (km/h) for judging the start of crawling (whether the current vehicle speed > the vehicle speed for judging the start of crawling), if the result of the judgment ( 205 ) is “No”, the routine proceeds To the process where it is determined that condition 1 is not satisfied ( 203 ), the control routine proceeds to condition 1 and ends ( 208 ). If the result of judgment (205) is "Yes", the routine proceeds to judgment (206) whether the idle switch is "on". In determination ( 206 ), the routine monitors whether the accelerator pedal is operated based on the detection signal from the accelerator opening sensor 7 , thereby determining whether the accelerator opening is “0%”. When judging ( 206 ) whether the idle switch is "on", if the result of the judgment ( 206 ) is "NO", the routine proceeds to the process ( 203 ) where it is judged that the condition 1 is not satisfied, and then proceeds to the control of the condition 1 The program ends (208). If the result of the judgment ( 205 ) is YES, the routine proceeds to the process of judging that the condition 1 is satisfied ( 207 ), and then proceeds to the end of the control routine of the condition 1 ( 208 ).

[0032] will refer to Figure 5 Operation is described in the control flow diagram following Condition 1 shown in .

[0033] When the control routine following Condition 1 is started ( 301 ), the routine proceeds to determine ( 302 ) whether Condition 1 is not satisfied. If the result of the judgment (302) is "Yes" (ie, the condition 1 is not satisfied), the routine proceeds to the judgment (303) whether the timer 12 has elapsed the set time BCT4. If the result of determining ( 302 ) whether Condition 1 is not satisfied is NO (ie, Condition 1 is satisfied), the routine proceeds to the process of zeroing the timer 12 ( 304 ). After the process of zeroing the timer 12 ( 304 ), the routine proceeds to the process of determining that the stop condition of the air conditioner 4 is satisfied ( 310 ), and then proceeds to the control routine after the condition 1 ends ( 311 ). When judging ( 303 ) whether the timer 12 has elapsed the set time, if the result of the judgment ( 303 ) is “Yes”, the routine proceeds to the process of setting the flag of the timer 12 to “0” ( 305 ) . If the result of judging ( 303 ) whether the timer 12 has elapsed the set time is "NO", the program proceeds to the process of setting the flag of the timer 12 to "1" ( 306 ), and then proceeds to using the timer 12 counts of processing (307). After the process of setting the flag of the timer 12 to "0" ( 305 ) and the process of counting with the timer 12 ( 307 ), the routine proceeds to a determination ( 308 ) whether the flag of the timer 12 is "0". When it is judged ( 308 ) whether the flag of the timer 12 is "0", if the result of the judgment ( 308 ) is "Yes", the routine proceeds to a process ( 309 ) in which it is judged that the stop condition of the air conditioner 4 is not satisfied ), and then proceed to the end of the control routine after Condition 1 (311). If the result of the judgment ( 308 ) is NO, the routine proceeds to the process ( 310 ) where it is determined that the stop condition of the air conditioner 4 is satisfied, and then proceeds to the end of the control routine after the condition 1 ( 311 ).

[0034] The present invention is not limited to the above-described embodiments, and various modifications can be made to the present invention.

[0035] For example, a special arrangement using the estimated brake negative pressure in place of the brake negative pressure may be employed. That is, in the prior art, when the brake negative pressure sensor or the brake negative pressure switch fails, the estimated brake negative pressure calculated from the atmospheric pressure, the number of revolutions of the engine, and the accelerator opening is used instead of the brake negative pressure value. The estimated brake negative pressure can also be used in place of the brake negative pressure in the control logic described in this embodiment of the invention. Described below Image 6 control logic. suppose when Image 6 When the conditions shown in are satisfied, the presumed brake negative pressure application conditions are satisfied. It is assumed that the estimated brake negative pressure application conditions are not satisfied when these conditions are not satisfied. First, when the vehicle air conditioner control device 1 is provided with a brake negative pressure sensor, the first AND gate AND11 determines whether (1) the selection constant is zero and (2) whether the brake negative pressure sensor is abnormal. When the vehicle air conditioner control device 1 is provided with a brake negative pressure switch, the second AND gate AND12 determines whether (1) the selection constant is 1; and (2) whether the brake negative pressure switch is abnormal. The first OR gate OR11 judges whether any one of the first and second AND gates AND11, AND11 is satisfied. Therefore, since the estimated brake negative pressure can be used in place of the brake negative pressure in the control logic disclosed in this embodiment of the present invention, it is possible to deal with the failure of the brake negative pressure sensor or the brake negative pressure switch, which can help for the improvement of control reliability.

[0036] The entire disclosure of Japanese Patent Application No. 2013-005125 filed on January 16, 2013, including the specification, drawings and claims, is hereby incorporated by reference.