Air-conditioning apparatus for automobiles

• US 4,877,081 A
• Filed: 03/20/1989
• Issued: 10/31/1989
• Est. Priority Date: 03/22/1988
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ohtsu, Eiichi
• Primary Examiner(s): FORD, JOHN K
• Application Number:
  US07/326,069
• Time in Patent Office: 225 Days
• Field of Search: 165/30, 165/42, 165/43, 62/133, 62/209, 62/229
• US Class Current: 165/202
• CPC Class Codes: B60H 1/0073 Control systems or circuits characterised by particular algorithms or computational models, e.g. fuzzy logic or dynamic models
• CPC Class Codes: B60H 1/00878 the components being temperature regulating devices
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor

Abstract

An air-conditioning apparatus for automobiles comprises a device for detecting the internal air temperature providing the temperature in the automobile cabin, a device for detecting the atmospheric air temperature, a device for setting a target value of the internal air temperature, a device for calculating a target value of the air blowdown temperature from the output signals of the aforementioned three devices, a device for calculating a compensation amount for the compressor capacity from the difference between the target value and the output signal of a device for detecting the actual air blowdown temperature, and a device for controlling the compressor capacity in accordance with the result of the calculation.

Claims

1. An air-conditioning apparatus for automobiles, comprising:

means for sucking in air and guiding said air to an air blowdown outlet open to a cabin of an automobile;

means for cooling the air sucked in including a variable capacity compressor operatively connected in a refrigeration circuit;

means for heating the air sucked in;

first control means interposed between said cooling means and heating means for controlling the amount of the sucked in air proceeding to the heating means;

means for detecting the internal air temperature representing the interior of the cabin of an automobile;

means for detecting the atmospheric air temperature;

means for detecting the air blowdown temperature at said air blowdown outlet into the cabin;

means for setting a target value of said internal air temperature;

means for calculating a target value of the air blowdown temperature from the output signals of the internal air temperature detection means, the atmospheric air temperature detection means and the internal air temperature target value setting means;

means for calculating a compensation amount of the compressor capacity from the difference between the target air blowdown temperature and the output signal of the air blowdown temperature detection means; and

second control means for controlling the compressor capacity on the basis of the output of said calculation means.

3. An apparatus according to claim 1, wherein said second control means includes means for controlling the compressor capacity in predetermined cycles.

5. An apparatus according to claim 1, further comprising means for detecting the acceleration of an automobile, said calculation means including means for calculating a new compensation amount for the compressor capacity on the basis of said preceding compensation amount and the output signal of said acceleration detection means.

7. An apparatus according to claim 3, further comprising means for detecting the air temperature at the outlet of said cooling means and means for setting a target value of the air temperature at said outlet,

said calculation means further including means for comparing the difference between the output signals of the means for setting the target value at the outlet of the cooling means and the means for detecting the air temperature at said outlet with a predetermined value;

and means for calculating a new compensation amount of said compressor capacity on the basis of the result of said comparison.

8. An apparatus according to claim 1, further comprising means for comparing the difference between the output signal of said blowdown temperature detection means at said air blowdown outlet and the output signal of the target air blowdown temperature setting means at said blowdown outlet with a predetermined value;

and

third control means for controlling the output of said first control means on the basis of the result of said comparison.

10. An apparatus according to claim 3, further comprising means for comparing the difference between the output signal of said blowdown temperature detection means at said air blowdown outlet and the output signal of said target air blowdown temperature setting means at said blowdown outlet with a predetermined value and third control means for controlling the output of said first control means on the basis of the result of said comparison.

12. An apparatus according to claim 5, further comprising means for comparing the difference between the output signal of said blowdown temperature detection means at said air blowdown outlet and the output signal of said target air blowdown temperature setting means at said blowdown outlet with a predetermined value, and third control means for controlling the output of said first control means on the basis of the result of said comparison.

2. An air-conditioning apparatus for automobiles, comprising:

means for sucking in air and guiding said air to a plurality of air blowdown outlets open to a cabin of an automobile;

means for cooling the air sucked in including a variable capacity compressor operatively connected in a refrigeration circuit;

means for heating the air sucked in;

first control means interposed between said cooling means and said heating means for controlling the amount of the sucked-in air proceeding to the heating means;

means for detecting the internal air temperature representing the temperature in the interior of the cabin of an automobile;

means for detecting the atmospheric air temperature;

means for detecting the air blowdown temperature at each of the plurality of air blowdown outlets;

means for determining an air blowdown outlet in operation;

means for setting a target value of the internal air temperature;

means for calculating a target value of the air blowdown temperature for each air blowdown outlet from the output signals of said internal air temperature detection means, said atmospheric air temperature detection means and said internal air temperature target setting means;

means for calculating a compensation amount for the compressor capacity from the difference between the lowest target air blowdown temperature of the blowdown outlet in operation as determined by said blowdown outlet determining means and the output signal of the blowdown temperature detection means for said blowdown outlet in operation; and

second control means for controlling the compressor capacity on the basis of the output of said calculation means.

4. An apparatus according to claim 2, wherein said second control means includes means for controlling the compressor capacity in predetermined cycles.

6. An apparatus according to claim 2, further comprising means for detecting the acceleration of an automobile, said calculation means including means for calculating a new compensation amount for the compressor capacity on the basis of said preceding compensation amount and the output signal of said acceleration detection means.

9. An apparatus according to claim 2, further comprising means for comparing the difference between the output signal of said blowdown temperature detection means at said air blowdown outlet in operation and the output signal of the target air blowdown temperature setting means at said blowdown outlet operation with a predetermined value;

and

third control means for controlling the output of said first control means on the basis of the result of said comparison.

11. An apparatus according to claim 4, further comprising means for comparing the difference between the output signal of said blowdown temperature detection means at said air blowdown outlet in operation and the output signal of said target air blowdown temperature setting means at said blowdown outlet in operation with a predetermined value, and third control means for controlling the output of said first control means on the basis of the result of said comparison.