Hybrid compressor with a selective drive clutch means and speed increasing means for driving the compressor at higher speeds with an engine at high load regions

• US 6,986,645 B2
• Filed: 12/05/2002
• Issued: 01/17/2006
• Est. Priority Date: 12/26/2001
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Uno, Keiichi, Iwanami, Shigeki, Suzuki, Yasushi
• Primary Examiner(s): Freay, Charles G.
• Assistant Examiner(s): Sayoc, Emmanuel
• Application Number:
  US10/310,028
• Publication Number:
  US 20030118450A1
• Time in Patent Office: 1,139 Days
• Field of Search: 417/42, 417/223, 417/16, 417/374, 417/362, 417/364, 417/423.6, 623/231, 622/36
• US Class Current: 417/16
• CPC Class Codes: B60H 1/3208 Vehicle drive related control of the compressor drive means, e.g. for fuel saving purposes
• CPC Class Codes: B60H 1/3222 characterised by the compressor driving arrangements, e.g. clutches, transmissions or multiple drives B60H1/3208, B60H1/3226 take precedence
• CPC Class Codes: B60H 2001/3236 information from a variable is obtained
• CPC Class Codes: B60H 2001/3266 related to the operation of the vehicle
• CPC Class Codes: B60H 2001/327 related to a compressing unit
• CPC Class Codes: B60H 2001/3294 Compressor drive is hybrid
• CPC Class Codes: F04B 27/0895 driving means
• CPC Class Codes: F04B 35/002 driven by internal combustion engines
• CPC Class Codes: F04B 35/04 the means being electric

Abstract

A hybrid compressor system affords maximum cooling capability by making full use of an additional motor to improve the fuel consumption efficiency of a vehicle while ensuring passenger compartment cooling when the engine is stopped. The hybrid compressor system includes a compression unit for compressing a refrigerant, a motor for driving the compression unit, and disconnection means for disconnecting the drive force of a vehicle engine. In the hybrid compressor system, when the thermal load of the refrigeration cycle system lies within a predetermined range in a higher load region, the control means connects the disconnection means to allow the vehicle engine to drive the compression unit. When the thermal load of the refrigeration cycle system lies within a lower load region of the predetermined range, the control means disconnects the disconnection means to allow the motor to drive the compression unit even while the vehicle engine is running.

Claims

1. A hybrid compressor system comprising:

a fixed displacement compression unit for compressing a refrigerant cycle system,

a motor powered by a power source to operatively rotate, for driving said compression unit,

a disconnection means for intermittently disconnecting a drive force of a vehicle engine transmitted to said compression unit, and

a control means for providing control to operate said motor and to allow said disconnection means to perform disconnection, wherein

when a thermal load on said refrigeration cycle system lies within a predetermined range in a higher load region said control means connects said disconnection means to allow said vehicle engine to drive said compression unit, and

when a thermal load on said refrigeration cycle system lies within a lower load region than said predetermined range, said control means disconnects said disconnection means to allow said motor to drive said compression unit even while said vehicle engine is running; and

the compressor system further includes;

an external drive means driven by said vehicle engine, provided on a side of said disconnection means closer to said vehicle engine, and

a speed increasing means for increasing a rotational speed of the compressor by increasing the rotational speed of a drive force transmitted from said vehicle engine, provided between said external drive means and said compression unit but not between said motor and said compression unit,

wherein said compression unit is increased in speed by said speed increasing means when the compression unit is driven by said vehicle engine,

said compression unit is in sync with the rotation speed of said motor when the compression unit is driven by said motor,

and wherein the motor drives the compressor at a higher speed in the higher load region than the speed driven by the motor in the lower region.

2. The hybrid compressor system according to claim 1, wherein

a boundary between the higher load region and the lower load region of said thermal load is delineated by a thermal load corresponding to a predetermined power level of said compression unit.

3. The hybrid compressor system according to claim 2, wherein

the cooling capability at a maximum thermal load is capable of cooling a vehicle passenger compartment during normal operation when said vehicle is subjected to sunlight.

4. The hybrid compressor system according to claim 1, wherein

said control means comprises an inverter for inverting power supplied to operate said motor, and

said motor and said inverter are set at a capability, as a maximum output, for delivering the power of said compression unit required in the boundary region between the higher load region and the lower load region of said thermal load.

5. The hybrid compressor system according to claim 1, wherein

said compression unit is a compression unit of a fixed volumetric capacity type having a discharge volume per one revolution set to a predetermined value, and

to allow said motor to drive said compression unit, said control means varies a rotation speed of said motor to control an amount of discharge from said compression unit.

6. The hybrid compressor system according to claim 1, further comprising:

a rotation speed sensor means for sensing a rotation speed of said vehicle engine or said compression unit, wherein

when said compression unit is driven by said vehicle engine and a rotation speed sensed by said rotation speed sensor means is determined to be greater than or equal to a predetermined rotation speed, said control means disconnects said disconnection means, or disconnects said disconnection means to allow said motor to drive said compression unit, and

when said rotation speed is below said predetermined rotation speed, said control means connects said disconnection means, or connects said disconnection means to stop said motor.

7. The hybrid compressor system according to claim 6, wherein said disconnection means is an electromagnetic clutch.

8. The hybrid compressor system according to claim 7, wherein when the thermal load on said refrigeration cycle system lies within the predetermined range in the higher load region, said control means connects said disconnection means to allow said vehicle engine and said motor to drive said compression unit.

9. A hybrid compressor system comprising:

a fixed displacement compressor for compressing a refrigerant in a refrigeration circuit;

a motor, which is powered by a power source, to drive the compressor;

a disconnection means for intermittently disconnecting a drive force of a vehicle engine transmitted to said compression unit, and

a clutch for selectively connecting and disconnecting a driving force of a vehicle engine to the compressor;

a controller that operates the motor and determines the state of the clutch, wherein;

when the thermal load on the refrigeration circuit lies within a predetermined hi-load region, in which the thermal load is higher than a predetermined level, the controller controls the clutch to allow the vehicle engine to drive the compressor; and

when the load on the refrigeration circuit lies within a predetermined low-load region, in which the thermal load is lower than that of the high-load region, the controller controls the clutch to prevent the vehicle engine from driving the compressor and controls the motor to drive the compressor even while the vehicle engine is running; and

a pulley driven by the vehicle engine, wherein the pulley is located on an engine side of the clutch, and the pulley transmits-torque from the engine to the compressor;

a speed increasing device located between the pulley and the compressor, but not between the motor and the compressor, wherein the speed increasing device increases the rotational speed of the compressor by increasing the rotational speed of a rotating drive force transmitted from the pulley to the compressor such that the compressor is increased in speed by the speed increasing device when the compressor is driven by the vehicle engine and such that the compressor is synchronized with the rotation speed of the motor when-the compressor is driven by the motor,

and wherein the motor drives the compressor at a higher speed in the higher load region than the speed driven by the motor in the lower region.

10. The hybrid compressor apparatus according to claim 9, wherein a boundary between the high-load region and the low-load region is delineated by a predetermined power level of the compressor.

11. The hybrid compressor apparatus according to claim 10, wherein the predetermined power level of the compressor corresponds to one-half of the maximum thermal load, and the maximum thermal load corresponds to a cooling capability at which a vehicle passenger compartment is cooled during normal operation when the vehicle is subjected to sunlight.

12. The hybrid compressor apparatus according to claim 10, wherein the controller comprises an inverter for inverting power supplied to the motor, and the maximum output of the motor and the inverter are sufficient to power the compressor in a region of the boundary between the high-load region and the low-load region.

13. The hybrid compressor apparatus according to claim 9, wherein:

the compressor is a compressor of a fixed volumetric capacity, in which the discharge volume per revolution is fixed; and

when the motor drives the compressor, the controller varies the rotation speed of the motor to control the discharge volume of the compressor.

14. The hybrid compressor apparatus according to claim 9, further comprising a rotation speed sensor for sensing a rotation speed of the vehicle engine or the compressor, wherein:

when the compressor is driven by the vehicle engine and a rotation speed sensed by the rotation speed sensor is determined to be greater than or equal to a predetermined rotation speed, the controller controls the clutch to prevent the engine from driving the compressor and controls the motor to cause the motor to drive the compressor, and

when the rotation speed is below the predetermined rotation speed, the controller stops the motor and controls the clutch to cause the engine to drive the compressor.

15. The hybrid compressor apparatus according to claim 9, wherein, when the thermal load on the refrigeration circuit lies within the high-load region, the controller to cause the motor to drive the compressor such that both the vehicle engine and the motor drive the compressor.

16. The hybrid compressor apparatus according to claim 9, wherein the speed increasing device is a set of gears.

17. The hybrid compressor apparatus according claim 9, wherein the pulley is coaxial with the compressor.

18. The hybrid compressor apparatus according to claim 9, wherein the pulley is driven by a belt, and the belt is driven by the engine.