Method and apparatus for controlling automobile air conditioners

• US 4,328,855 A
• Filed: 10/17/1979
• Issued: 05/11/1982
• Est. Priority Date: 10/20/1978
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Iwata, Yasuhiro, Usami, Kiyoshi, Nabeta, Teiichi, Naganoma, Masanori, Kojima, Yasuhumi
• Primary Examiner(s): Scott, Samuel
• Assistant Examiner(s): Focarino, Margaret A.
• Application Number:
  US06/085,510
• Time in Patent Office: 937 Days
• Field of Search: 237/12.3 A, 236/82, 236/84, 165/12, 165/23, 165/27, 165/28, 165/30, 165/42, 165/43, 165/44, 165/2
• US Class Current: 165/202
• CPC Class Codes: B60H 1/00835 Damper doors, e.g. position control construction or arrangement of damper doors B60H1/00664; B60H1/00864 takes precedence
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence

Abstract

A method and apparatus for controlling an automobile air conditioner wherein a deviation between the actual in-car temperature and a desired in-car temperature is periodically calculated to detect such various thermal disturbances as changes of the solar heat, the temperature of outside air, the number of passengers and the like, and wherein a compensation value of the opening angle of the air-blend door is determined in accordance with the periodical variation of the deviation to ensure stable control of the in-car temperature.

Claims

1. A method for controlling an automobile air conditioner in which a control member is provided to adjust the output of said air conditioner from maximum heating to maximum cooling according to its position, the method comprising the steps of:

generating a first electric signal indicative of the actual in-car temperature, a second electric signal indicative of a desired in-car temperature, and a feedback signal indicative of the position of said control member;

calculating, in sequence, the deviation between the actual in-car temperature and the desired in-car temperature in response to said first and second electric signals at a predetermined time interval;

discriminating the previously calculated deviation in relation to the subsequently calculated deviation to detect a tendency of variation of the deviations;

determining a compensation value related to the calculated deviations in dependence upon the discrimination result of the deviations;

discriminating a value of said feedback signal in relation to the compensation value to generate an output signal in accordance with the compensation value taking into account the feedback signal value; and

controlling the position of said control member in response to the output signal to direct the actual in-car temperature towards the desired in-car temperature.

2. A method for controlling an automobile air conditioner as claimed in claim 1, wherein the step of calculating, in sequence, the temperature deviation further includes the following step of;

performing a first comparison by comparing the calculated deviation with a predetermined value to selectively produce first and second proceeding signals in dependence upon the comparison result; and

wherein the step of discriminating the previously calculated deviation with the subsequently calculated deviation is conducted in response to one of said proceeding signals to detect a tendency of variation of the deviations.

3. A method for controlling an automobile air conditioner as claimed in claim 2, wherein the step of comparing the calculated deviation with a predetermined value further includes the steps of:

performing a second comparison by comparing the calculated deviation with a second predetermined value in response to said second proceeding signal to produce a third proceeding signal in dependence upon the result of said second comparison, and wherein the step of discriminating the feedback signal value includes the step of generating an output signal in response to said third proceeding signal to maintain said control member in its adjusted position.

4. A method for controlling an automobile air conditioner in which a control member is provided to adjust the output of said air conditioner from maximum heating to maximum cooling according to its position, the method comprising the steps of:

generating a first electric signal indicative of the actual in-car temperature, a second electric signal indicative of a desired in-car temperature, and a feedback signal indicative of the position of said control member;

calculating, in sequence, the deviation between the actual in-car temperature and the desired in-car temperature at a predetermined time interval;

performing a first comparison by comparing the calculated deviation with a first predetermined positive value to selectively produce first and second proceeding signals in dependence upon the first comparison result;

performing a second comparison by comparing the calculated deviation with a first predetermined negative value in response to said second proceeding signal to produce a third proceeding signal in dependence upon the result of said second comparison;

performing a third comparison by comparing the calculated deviation with a second predetermined positive value in response to said first proceeding signal to selectively produce first and second control signals in dependence upon the result of said third comparison and performing a fourth comparison by comparing the calculated deviation with a third predetermined positive value in response to said second control signal to produce a third control signal in dependence upon the result of said fourth comparison;

performing a fifth comparison by comparing the calculated deviation with a second predetermined negative value in response to said second proceeding signal to selectively produce fourth and fifth control signals in dependence upon the result of said fifth comparison and performing a sixth comparison by comparing the calculated deviation with a third predetermined negative value in response to said fifth control signal to produce a sixth control signal in dependence upon the result of said sixth comparison;

discriminating the previously calculated deviation in relation to the subsequently calculated deviation in response to one of said first, second, fourth and fifth control signals to detect a tendency of variation of the deviations;

determining a compensation value in accordance with the discrimination result of the deviations;

comparing a value of said feedback signal with the compensation value to generate a first output signal in accordance with the compensation value taking into account the feedback signal value;

generating second and third output signals respectively in response to said third and sixth control signals; and

controlling said control member in response to said first output signal to direct the actual in-car temperature towards the desired in-car temperature, adjusting said control member to its maximum cooling position in response to said second output signal, and adjusting said control member to its maximum heating position in response to said third output signal.

5. An electric control system for an automobile air conditioner in which a control member is provided to adjust the output of said air conditioner from maximum heating to maximum cooling according to its position, comprising:

an in-car temperature sensor exposed to the temperature in a passenger compartment for generating a first electric signal indicative of the actual in-car temperature;

a temperature selector for generating a second electric signal indicative of a desired in-car temperature;

a position sensor responsive to movement of said control member for generating an electric feedback signal indicative of the position of said control member;

first means responsive to said first and second electric signals for calculating, in sequence, the deviation between the actual in-car temperature and the desired in-car temperature at a predetermined time interval and for comparing the calculated deviation with a first predetermined value to selectively produce first and second proceeding signals in dependence upon the comparison result and comparing the calculated deviation with a second predetermined value in response to said second proceeding signal to produce a third proceeding signal in dependence upon the result of said second-named comparison, said first means being responsive to one of said first and second proceeding signals for discriminating the previously calculated deviation in relation to the subsequently calculated deviation to detect a tendency of variation of the deviations and for determining a compensation value in accordance with the discrimination result of the deviations;

second means responsive to said feedback signal for discriminating a value of said feedback signal in relation to the compensation value to generate a first output signal in accordance with the compensation value taking into account the feedback signal value, said second means being further responsive to said third proceeding signal from said first means for generating a second output signal; and

an actuator for controlling the position of said control member in response to the first output signal from said second means to direct the actual in-car temperature towards the desired in-car temperature and for maintaining said control member in its adjusted position in response to the second output signal from said second means.

6. An electric control system for an automobile air conditioner in which a control member is provided to adjust the output of said air conditioner from maximum heating to maximum cooling according to its position, comprising:

an in-car temperature sensor exposed to the temperature in a passenger compartment for generating a first electric signal indicative of the actual in-car temperature;

a temperature selector for generating a second electric signal indicative of a desired in-car temperature;

a position sensor responsive to movement of said control member for generating an electric feedback signal indicative of the position of said control member;

a computer programmed to calculate, in sequence, the deviation between the actual in-car temperature and the desired in-car temperature at a predetermined time interval, to perform a first comparison by comparing the calculated deviation with a first predetermined positive value to selectively produce first and second proceeding signals in dependence upon the first comparison result, to perform a second comparison by comparing the calculated deviation with a first predetermined negative value in response to said second proceeding signal to produce a third proceeding signal in dependence upon the result of said second comparison, to perform a third comparison by comparing the calculated deviation with a second predetermined positive value in response to said first proceeding signal to selectively produce first and second control signals in dependence upon the result of said third comparison, to perform a fourth comparison by comparing the calculated deviation with a third predetermined positive value in response to said second control signal to produce a third control signal in dependence upon the result of said fourth comparison, to perform a fifth comparison by comparing the calculated deviation with a second predetermined negative value in response to said second proceeding signal to selectively produce fourth and fifth control signals in dependence upon the result of said fifth comparison, and to perform a sixth comparison by comparing the calculated deviation with a third predetermined negative value in response to said fifth control signal to produce a sixth control signal in dependence upon the result of said sixth comparison;

said computer being further programmed to discriminate the previously calculated deviation in relation to the subsequently calculated deviation in response to one of said first, second, fourth, and fifth control signals, to determine a compensation value in accordance with the discrimination result of the deviations, to compare a value of said feedback signal with the compensation value to generate a first output signal in accordance with the compensation value taking into account the feedback signal value and to generate second and third output signals respectively in response to said third and sixth control signals; and

an actuator for controlling the position of said control member in response to the first output signal from said computer to direct the actual in-car temperature towards the desired in-car temperature, for adjusting said control member to its maximum cooling position in response to the second output signal from said computer, and for adjusting said control member to its maximum heating position in response to the third output signal from said computer.