Hybrid compressor device

CROSS-REFERENCE TO RELATED APPLICATION

This application is related to and claims priority from Japanese Patent Applications No. 2001-366706 filed on Nov. 30, 2001, No. 2002-196053 filed on Jul. 4, 2002, No. 2002-223638 filed on Jul. 31, 2002, and No. 2002-284142 filed on Sep. 27, 2002, the contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a hybrid compressor device suitable for a refrigerant cycle system mounted in an idling stop vehicle, where a vehicle engine is stopped when the vehicle is temporally stopped.

2. Description of Related Art

Recently, the market for an idling stop vehicle has been increased to save fuel consumption. In a case where a compressor is driven only by an engine of the vehicle, when the vehicle is temporarily stopped, its engine is stopped, so that the compressor, driven by the engine, is also stopped in a refrigerant cycle system. In order to overcome this problem, in a conventional hybrid compressor device disclosed in JP-A-2000-130323 (corresponding to U.S. Pat. No. 6,375,436), driving force of the engine is transmitted to a pulley through a solenoid clutch, and one end of a rotational shaft of the compressor is connected to the pulley. Further, the other end of the rotational shaft of the compressor is connected to a motor. Accordingly, when the engine is stopped, the solenoid clutch is turned off, and the compressor is driven by the motor, so that the refrigerant cycle system can be operated regardless of the operation of the engine.

However, the hybrid compressor device requires the solenoid clutch for switching a driving source of the compressor between the engine in the operation of the engine, and the motor in the stop of the engine. Therefore, production cost of the hybrid compressor device is increased. Further, the compressor is operated by one of both the driving sources of the engine and the motor. Therefore, a discharge capacity of the compressor and a size thereof are need to be set based on a maximum heat load of the refrigerant cycle system in a driving force range of each driving source. For example, when a cool down mode (quickly cooling mode) is selected directly after the start of the vehicle in the summer, the heat load of the compressor becomes in maximum. Thus, the discharge capacity of the compressor and the size thereof are set so as to satisfy the maximum heat load, thereby increasing the size of the compressor.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above problem, and its object is to provide a hybrid compressor device capable of reducing its production cost and its size, while ensuring cooling performance after the stop of a vehicle engine.

It is an another object of the present invention to provide a hybrid compressor device which has improved reliability while being produced in low cost.

According to the present invention, a hybrid compressor device includes a pulley rotated by a vehicle engine that is stopped when the vehicle is temporally stopped, a motor rotated by electric power from a battery of the vehicle, a compressor operated by driving force of the pulley and driving force of the motor, a transmission mechanism for changing and transmitting rotation force, and a control unit for adjusting the rotational speed of the motor. Here, the compressor is for compressing refrigerant in a refrigerant cycle system provided in the vehicle. The transmission mechanism is connected to a rotational shaft of the pulley, a rotational shaft of the motor and a rotational shaft of the compressor, so that a rotational speed of the pulley and a rotational speed of the motor are changed and transmitted to the compressor. In the hybrid compressor device, the pulley, the motor and the compressor are disposed to be rotatable independently. Further, the control unit changes the rotational speed of the compressor by adjusting the rotational speed of the motor with respect to the rotational speed of the pulley. Accordingly, the rotational speed of the compressor can be increased and decreased with respect to the rotational speed of the pulley, thereby changing a discharge capacity of the compressor. When the heat load of the refrigerant cycle system becomes maximum as in a cool down mode (quickly cooling mode), the discharge amount of the compressor can be effectively increased by increasing the rotational speed of the compressor than the rotation speed of the pulley by the adjustment of the rotation speed of the motor. Therefore, the size of the compressor and the discharge amount of the compressor can be set smaller. On the contrary, the discharge amount of the compressor can be reduced by reducing the rotational speed of the compressor than the rotation speed of the pulley by the adjustment of the rotation speed of the motor. Therefore, the compressor can quickly corresponds to the heat load of the refrigerant cycle system in a normal cooling mode after the end of the cool down mode. Furthermore, even when the engine is stopped due to idling stop and the rotational speed of the pulley becomes zero, the compressor can be operated by operating the motor. Therefore, even in the idling stop time, cooling operation can be maintained in low cost without using a solenoid clutch.

Preferably, the transmission mechanism is a planetary gear including a sun gear, a planetary carrier and a ring gear, and the rotational shafts of the pulley, the motor and the compressor are connected to the sun gear, the planetary carrier and the ring gear of the planetary gear. Here, the connection between the rotation shafts of the pulley, the motor and the compressor, and the sun gear, the planetary carrier and the ring gear of the planetary gear can be arbitrarily changed. For example, the rotational shaft of the compressor is connected to the planetary carrier, the rotational shaft of the pulley is connected to the sun gear, and the rotational shaft of the motor is connected to the ring gear. Alternatively, the rotational shaft of the pulley is connected to the planetary carrier, the rotational shaft of the motor is connected to the sun gear, and the rotational shaft of the compressor is connected to the ring gear. Alternatively, the rotational shaft of the motor is connected to the sun gear, and the rotational shaft of the compressor is connected to the ring gear, and the rotation shaft of the compressor is connected to the planetary carrier.

Preferably, a lock mechanism is provided for locking the rotational shaft of the motor when the motor is stopped. In this case, when the compressor is operated by driving force of the pulley while the motor is stopped, the control unit detects fluctuation of an induced voltage of the motor by detecting leakage fluctuation of magnetic flux of the motor generated due to rotation of the transmission mechanism connected to the compressor. Accordingly, when a trouble such as lock is caused in the compressor, the rotation of the transmission mechanism is reduced or becomes zero, so that the fluctuation of the induced voltage becomes smaller. Thus, an abnormal operation of the compressor can be readily detected by effectively using the fluctuation of the magnetic flux of the motor.

The hybrid compressor device of the present invention can be applied to a vehicle having an engine that is stopped in a predetermined running condition of the vehicle having a driving motor for driving the vehicle.

On the other hand, in a hybrid compressor where a compressor for compressing refrigerant in a refrigerant cycle system is operated by at least one of a driving unit and a motor, the compressor includes a suction area into which refrigerant before being compressed is introduced, a discharge area into which compressed refrigerant flows, and an oil separating unit for separating lubrication oil contained in refrigerant from the refrigerant and for storing the separated lubrication oil in the discharge area. Further, a transmission mechanism is disposed between the compressor and at least any one of the driving unit and the motor, for changing a rotational speed of the at least one of the driving unit and the motor, to be transmitted to the compressor. In addition, both of the motor and the transmission mechanism are disposed in a housing, an oil introducing passage is provided so that the lubrication oil stored in the discharge area is introduced into the housing through the oil introducing passage, and an inner space of the housing communicates with the suction area of the compressor through a communication passage.

Accordingly, lubrication oil contained in refrigerant is separated from the refrigerant by the oil separating unit, and the separated lubrication oil is introduced into the housing. Further, the introduced lubrication oil is circulated from the housing into the suction area of the compressor. Therefore, lubrication oil can be always supplied to the transmission mechanism in the housing, thereby improving reliability of the transmission mechanism. Further, since the motor is also disposed in the housing, the motor can be cooled by the lubrication oil, thereby improving reliability of the motor. Because lubrication oil is separated from the refrigerant by the oil separating unit, refrigerant, circulated in the refrigerant cycle system, contains almost no lubrication oil. Therefore, lubrication oil is not adhered to a heat exchanger such as an evaporator provided in the refrigerant cycle system, thereby preventing heat-exchange efficiency of the heat exchanger from being reduced.

Preferably, the housing is disposed to accommodate the compressor, the motor and the transmission mechanism. Further, the housing has a suction port, from which the refrigerant is sucked into the compressor, at a side where the motor and the transmission mechanism are disposed. Therefore, the motor and the transmission mechanism can be effectively cooled by the refrigerant introduced into the housing.

More preferably, the oil introduction passage is a first decompression passage through which the discharge area of the compressor communicates with the inside of the housing while pressure is reduced from the discharge area of the compressor toward the inside of the housing, and the communication passage is a second decompression passage through which the inside of the housing communicates with the suction area of the compressor while the pressure is reduced from the inside of the housing toward the suction area of the compressor. Therefore, the lubrication oil can be smoothly circulated between the compressor and the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional objects and advantages of the present invention will be more readily apparent from the following detailed description of preferred embodiments when taken together with the accompanying drawings, in which:

FIG. 1

is an entire schematic diagram showing a refrigerant cycle system to which the present invention is typically applied;

FIG.

2

. is a cross-sectional view showing a hybrid compressor device according to a first embodiment of the present invention shown in

FIG. 1

;

FIG. 3

is a front view showing a planetary gear taken from the arrow III in

FIG. 2

;

FIG. 4A

is a control characteristic graph showing a relationship between a discharge amount of a compressor and a heat load of the refrigerant cycle system according to the first embodiment, and

FIG. 4B

is a control characteristic graph showing a relationship between the discharge amount of the compressor and a rotational speed of the compressor according to the first embodiment;

FIG. 5

is a graph showing rotational speeds of a pulley, the compressor and a motor of the hybrid compressor which are shown in

FIG. 2

;

FIG. 6

is a cross-sectional view showing a hybrid compressor device according to a second embodiment of the present invention;

FIG. 7

is a graph showing rotational speeds of a pulley, a compressor and a motor of the hybrid compressor device, according to the second embodiment;

FIG. 8

is a cross-sectional view showing a hybrid compressor device according to a third embodiment of the present invention;

FIG. 9

is a graph showing rotational speeds of a pulley, a compressor and a motor of the hybrid compressor device, according to the third embodiment;

FIG. 10

is a front view showing a planetary gear including recess portions and protrusion portions according to a fourth embodiment of the present invention;

FIG. 11

is an enlarged schematic diagram showing magnetic flux and leaked magnetic flux in the motor, according to the fourth embodiment;

FIG. 12

is a graph showing fluctuation of an induced voltage of the motor relative to a time according to the fourth embodiment;

FIG. 13

is flow diagram showing a control process for detecting the fluctuation of the induced voltage of the motor and for protecting a vehicle engine, according to the fourth embodiment;

FIG. 14

is a cross-sectional view showing a hybrid compressor device according to a modification of the fourth embodiment;

FIG. 15

is a cross-sectional view showing a hybrid compressor device according to a fifth embodiment of the present invention; and

FIG. 16

is a cross-sectional view showing a hybrid compressor according to a sixth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described hereinafter with reference to the appended drawings.

(First Embodiment)

The first embodiment of the present invention will be now described with reference to

FIGS. 1-5

. In

FIG. 1

, a hybrid compressor device

100

is typically applied to a refrigerant cycle system

200

mounted in an idling stop vehicle where a vehicle engine

10

is stopped when the vehicle is temporally stopped. The hybrid compressor device

100

includes a hybrid compressor

101

and a control unit

160

. The refrigerant cycle system

200

includes components such as a compressor

130

, a condenser

210

, an expansion valve

220

and an evaporator

230

. The components are sequentially connected by refrigerant piping

240

, to form a closed circuit. The compressor

130

constructs the hybrid compressor

101

. The compressor

130

compresses refrigerant, circulating in the refrigerant cycle system, to a high temperature and high pressure. The compressed refrigerant is condensed in the condenser

210

, and the condensed refrigerant is adiabatically expanded by the expansion valve

220

. The expanded refrigerant is evaporated in the evaporator

230

, and air passing the evaporator

230

is cooled due to the evaporation latent heat of the evaporated refrigerant. An evaporator temperature sensor

231

is disposed at a downstream air side of the evaporator

230

, for detecting a temperature of air cooled by the evaporator

230

(post-evaporator air temperature) Te. The post-evaporator air temperature Te is a representative value used for determining a heat load of the refrigerant cycle system

200

.

The hybrid compressor

101

is mainly constructed by a pulley

110

, a motor

120

disposed in a housing

140

and the compressor

130

. As shown in

FIG. 2

, the pulley

110

includes a pulley rotational shaft

111

at a center of itself, and is rotatablly supported by the housing

140

through bearings

112

,

113

. Driving force of the engine

10

is transmitted to the pulley

110

through a belt

11

, so that the pulley

110

is rotated. The motor

120

includes magnets

122

constructing a rotor, and a stator

123

. The magnets

122

are fixed to an outer periphery of a ring gear

153

constructing a planetary gear

150

described later, and the stator

123

is fixed to an inner periphery of the housing

140

. The motor

120

has a motor rotational axis

121

, shown by a chain line in

FIG. 2

, at a center of the magnets

122

, that is, at a center of the ring gear

153

. Electric power is supplied to the stator

123

from a battery

20

as a power source, so that the magnets

122

are rotated.

The compressor

130

is a fixed displacement compressor where a discharge capacity is fixed at a predetermined value. More specifically, the compressor

130

is a scroll type compressor. The compressor

130

includes a fixed scroll

136

fixed to the housing

140

and a movable scroll

135

revolved about a compressor rotational shaft

131

by an eccentric shaft

134

provided at a top end of the compressor rotational shaft

131

. The compressor rotational shaft

131

is rotatablly supported by a partition plate

141

through a bearing

132

provided on the partition plate

141

. Refrigerant is sucked into the housing

140

from a suction port

143

provided on the housing

140

, and flows into a compressor chamber

138

through a through hole

144

provided in the partition plate

141

. Then, the refrigerant is compressed in the compression chamber

137

, and is discharged from a discharge port

139

through a discharge chamber

138

. Here, the sucked refrigerant contacts the motor

120

, so that the motor

120

is cooled by the sucked refrigerant, thereby improving durability of the motor

120

.

In the present invention, as described later, the compressor

130

is driven by operating both of the pulley

110

and the motor

120

in accordance with the heat load of the refrigerant cycle system

200

. Therefore, the discharge capacity of the compressor

130

and its size can be smaller than those of a compressor driven by operation of any one of the pulley

110

and the motor

120

. For example, the discharge capacity and the size of the compressor

130

can be set at ½-⅓ of those of the compressor driven by the operation of one of the pulley

110

and the motor

120

. The pulley rotational shaft

111

, the motor

120

, and the compressor rotational shaft

131

are connected to the planetary gear

150

as a transmission mechanism disposed in the housing

140

. The rotational speed of the pulley

110

and the rotational speed of the motor

120

are changed and transmitted to the compressor

130

by the planetary gear

150

. As shown in

FIG. 3

, the planetary gear

150

includes a sun gear

151

at a center of itself, planetary carriers

152

connected to pinion gears

152

a

, and a ring gear

153

provided outside the pinion gears

152

a

at an opposite side of the sun gear

150

. Each pinion gear

152

a

rotates, and revolves about the sun gear

151

. When the planetary gear

150

is rotated, the following relationship is satisfied among the driving force of the sun gear

151

(sun gear torque), the driving force of the planetary carriers

152

(planetary carrier torque) and the driving force of the ring gear

153

(ring gear torque).

planetary carrier torque=sun gear torque+ring gear torque

Here, the pulley rotational shaft

111

is connected to the sun gear

151

, and the motor

120

is connected to the ring gear

153

. The compressor rotational shaft

131

is connected to the planetary carries

152

.

The control unit

160

inputs an air-conditioning (A/C) requirement signal, a temperature signal from the evaporator temperature sensor

231

, an engine rotational speed signal and the like, and controls the operation of the motor

120

based on the input signals. Specifically, the control unit

160

changes a rotational speed of the motor

120

by changing electric power from the battery

20

. The control unit

160

determines a refrigerant discharge amount of the compressor

130

in accordance with the heat load of the refrigerant cycle system

200

, based on a control characteristic shown in FIG.

4

A. Similarly, the control unit

160

determined a rotational speed of the compressor

130

to ensure the refrigerant discharge amount, based on a control characteristic shown in FIG.

4

B. The discharge amount is defined by multiplying the discharge capacity per rotation of the compressor

130

and a the rotational speed of the compressor

130

together. As the rotational speed of the compressor

130

is increased, the discharge amount of the compressor

130

is increased. The control unit

160

determines the rotational speed of the motor

120

by using the rotational speed of the pulley

110

and the rotational speed of the compressor

130

, based on the graph of the planetary gear

150

shown in FIG.

5

.

Next, operation of the above structure according to the first embodiment will be described. In the hybrid compressor

101

, the compressor

130

is operated by the rotational driving force of the pulley

110

, and by the rotational driving force of the motor

120

through the planetary gear

150

. The rotational speed of the motor

120

is adjusted by the control unit

160

, and the rotational speed of the compressor

130

is increased and decreased with respect to the rotational speed of the pulley

110

.

FIG. 5

shows the rotation speed of the sun gear

151

, the planetary carriers

152

and ring gear

153

. In the abscissa of

FIG. 5

, a position of the planetary carriers

152

is determined by a gear ratio of the ring gear

153

to the sun gear

151

. Here, the gear ratio is set at 0.5. The rotational speeds of the sun gear

151

, the planetary carriers

152

and ring gear

153

are located on a straight line in FIG.

5

. The control unit

160

calculates the rotational speed of the pulley

110

from the rotational speed signal of the engine

10

. Then, as shown in

FIGS. 4A

,

4

B, the control unit

160

determines the rotational speed of the compressor

130

to ensure the discharge amount thereof required for the heat load of the refrigerant cycle system

200

. In the graph of

FIG. 5

, a straight line is drawn from the calculated rotational speed of the pulley

110

to the determined rotational speed of the compressor

130

. Since the rotational speed of the motor

120

is located on the extension line of the straight line, the rotational speed of the motor

120

is determined based on the graph of FIG.

5

. Thus, the motor

120

is operated at the determined rotational speed.

Further, operational control of the motor

120

will be specifically described with reference to FIG.

5

. In a cool down mode (quickly cooling mode) where the heat load of the refrigerant cycle system

200

becomes maximum, as shown by the straight line A in

FIG. 5

, the rotational speed of the motor

120

is increased, so that the rotational speed of the compressor

130

is made higher than the rotational speed of the pulley

110

. Thus, the discharge amount of the compressor

130

is increased, and the compressor

130

can be operated to correspond to the high heat load of the refrigerant cycle system

200

.

In a normal cooling mode after the end of the cool down mode, the increased discharge amount of the compressor

130

is not required. Therefore, as shown by the straight line B in

FIG. 5

, the rotational speed of the motor

120

is reduced, and the rotational speed of the compressor

130

is made lower than the rotational speed of the pulley

110

. Thus, the discharge amount of the compressor

130

is reduced to a discharge amount required in the normal cooling mode.

When the heat load of the refrigerant cycle system

200

is further reduced and the discharge amount of the compressor

130

becomes surplus, the motor

120

is operated in an inverse rotational direction as shown by the straight line C in

FIG. 5

, and the rotational speed of the compressor is set at zero. Thus, the discharge amount of the compressor

130

is set at zero. That is, the discharge amount of the compressor

130

can be set zero by adjusting the rotational speed of the motor

120

without using a solenoid clutch as in the conventional art. In this case, the motor

120

receives rotational force from the planetary carriers

152

connected to the compressor

130

, and is rotated in the inverse rotational direction to generate electric power.

In the normal cooling mode, when the vehicle runs at a high speed, the motor

120

is operated in the inverse rotational direction as shown by the straight line D, and the compressor

130

is operated at the same rotational speed as in the straight line B. Thus, the normal cooling mode is maintained while ensuring the same discharge amount of the compressor

130

as in the normal cooling mode when the vehicle runs in a normal speed. In the cases of the straight lines C, D of

FIG. 5

, the motor

120

is operated in the inverse rotational direction, and power generation can be performed, so that the battery

20

is charged. Further, when the idling stop vehicle is temporarily stopped and the engine

10

is stopped, that is, when the rotational speed of the pulley

110

becomes zero as shown by the straight line E in

FIG. 5

, the motor

120

is operated at an intermediate rotational speed level, and the rotational speed of the compressor

130

is maintained at the same rotational speed as in the straight line B in FIG.

5

. Accordingly, even when the engine

10

stops, the required discharge amount of the compressor

130

is ensured, and operation of the refrigerant cycle system

200

is continued.

Next, operational effects of the hybrid compressor device having the above structure will be described. The rotational speed of the compressor

130

can be increased and decreased with respect to the rotational speed of the pulley

110

by the adjustment of the rotational speed of the motor

120

. Thus, the discharge amount of the compressor

130

is changed based on the rotation speed of the pulley

110

and the rotation speed of the motor

120

. Further, the rotational speed of the compressor

130

can be increased than the rotational speed of the pulley

110

, so that the discharge amount of the compressor

130

can be increased than the discharge amount of the compressor according to the prior art. Therefore, the size of the compressor

130

and the discharge amount thereof can be set smaller than those in the prior art. On the contrary, the rotational speed of the compressor

130

can be reduced than the rotational speed of the pulley

110

, so that the discharge amount of the compressor

130

can be reduced. Therefore, the compressor

130

can be operated to quickly correspond to the heat load of the refrigerant cycle system

200

in the normal cooling mode after the end of the cool down mode. Furthermore, even when the engine

10

is stopped due to the idle stop and the rotational speed of the pulley

110

becomes zero, the compressor

130

can be operated by operating the motor

120

. Therefore, in the idling stop time, the cooling mode can be maintained in low cost without using a solenoid clutch.

Since the rotational shaft

131

of the compressor

130

is connected to the planetary carriers

152

, both of the driving force of the pulley

110

and the driving force of the motor

120

can be applied to the compressor rotational shaft

131

through the planetary gear

150

including the sun gear

151

, the planetary carriers

152

and the ring gear

153

. Therefore, both of energy of the pulley

110

and energy of the motor

120

can be supplied to the compressor

130

, thereby reducing the load of the engine

10

. Further, the pulley rotational shaft

111

is connected to the sun gear

151

, and the motor

120

is connected onto the ring gear

153

. Therefore, the pulley rotational shaft

111

, the compressor rotational shaft

131

and the motor

120

can be connected to the sun gear

151

, the planetary carriers

152

and the ring gear

153

, respectively, with a simple structure. As a result, production cost of the hybrid compressor

101

can be reduced. Since the discharge amount of the compressor

130

can be changed by adjusting the rotational speed of the motor

120

, the hybrid compressor

101

can be constructed by using the fixed displacement compressor

130

, thereby further reducing production cost of the hybrid compressor

101

.

In the above-described first embodiment, the rotation axis

121

of the motor

120

is described. However, actually, the motor

120

is rotated by a motor shaft (

121

).

(Second Embodiment)

The second embodiment of the present invention will be now described with reference to

FIGS. 6 and 7

.

In the second embodiment, as shown in

FIG. 6

, the planetary gear

150

is disposed in a rotor portion

120

a

of the motor

120

, and the pulley rotational shaft

111

, the rotation shaft of the motor

120

and the compressor rotational shaft

131

are connected to the planetary gear

150

, as compared with the first embodiment. Further, a solenoid clutch

170

and a one-way clutch

180

are added to the hybrid compressor

101

as compared with the first embodiment. Here, a surface permanent-magnet motor (SP motor), where permanent magnets are provided on an outer periphery of the rotor portion

120

a

, is used as the motor

120

. The planetary gear

150

is disposed in a space of the rotor portion

120

a

on the inner periphery side. The pulley rotational shaft

111

is connected to the planetary carriers

152

, and the rotor portion

120

a

of the rotor

120

is connected to the sun gear

151

. The compressor rotational shaft

131

is connected onto the ring gear

153

. The rotor portion

120

a

and the ring gear

153

can be rotated in independent from the pulley rotational shaft

111

by a bearing

114

.

The solenoid clutch

170

and the one-way clutch

180

are provided on the pulley rotational shaft

111

. The solenoid clutch

170

is for interrupting the driving force from the engine

10

to the pulley rotational shaft

111

, and is constructed by a coil

171

and a hub

172

. The hub

172

is fixed to the pulley rotational shaft

111

. When the coil

171

is energized, the hub

172

contacts the pulley

110

, and the solenoid clutch

170

is turned on, so that the pulley rotational shaft

111

is rotated together with the pulley

110

. When the coil

171

is de-energized, the hub

172

and the pulley rotational shaft

111

are separated from the pulley

110

, and the solenoid clutch

170

is turned off. The on-off operation of the solenoid clutch

170

is performed by the control unit

160

. The one-way clutch

180

is disposed near the planetary gear

150

between the planetary gear

150

and the solenoid clutch

170

in the axial direction of the pulley rotation shaft

111

, and is fixed to the housing

140

. The one-way clutch

180

allows the pulley rotational shaft

111

to rotate only in a regular rotational direction, and prevents the pulley rotational shaft

111

from rotating in an inverse rotational direction.

Next, operation of the hybrid compressor having the above structure according to the second embodiment will be described with reference to FIG.

7

. In the cool down mode where the maximum compression capacity is required, the solenoid clutch

170

is turned on, and the driving force of the pulley

110

is transmitted from the pulley rotational shaft

111

to the compressor rotational shaft

131

through the planetary gear

150

. In this case, the compressor

130

is operated, and the one-way clutch

180

is in idling. At this time, as shown by the straight line F in

FIG. 7

, the motor

120

is rotated in an inverse direction from the rotational direction of the pulley

110

, thereby increasing the rotational speed of the compressor

130

than the rotational speed of the pulley

110

, and increasing the discharge amount of the compressor

130

. As the rotational speed of the motor

120

is increased, the rotational speed of the compressor

130

is increased.

In the normal cooling mode after the cool down mode, the solenoid clutch

170

is turned on, and the motor

120

and the compressor

130

are operated mainly by the driving force of the pulley

110

while the one-way clutch

180

is in idling. At this time, since the compressor

130

performs compression work, operation torque of the compressor

130

is larger than operation torque of the motor

120

. Therefore, as shown by the straight line G in

FIG. 7

, the compressor

130

is operated at a lower rotational speed than the pulley

110

, and the discharge amount of the compressor

130

is reduced. On the other hand, the motor

120

is operated as a generator at a higher rotational speed higher than the pulley

110

, and the motor

120

charges the battery

20

. Here, as the rotational speed of the motor

120

is reduced, the rotational speed of the compressor

130

is increased.

When the engine

10

is stopped, the solenoid clutch

170

is turned off, the compressor

130

is operated by the driving force of the motor

120

. At this time, as shown by the straight line H in

FIG. 7

, the motor

120

is operated in the inverse rotational direction, and driving force of the motor

120

is applied to the pulley rotational shaft

111

in the inverse rotational direction. In this case, the pulley

110

is locked by the one-way clutch

180

, and the driving force of the motor

120

is transmitted to the compressor

130

. Here, as the rotational speed of the motor

120

is increased and reduced, the rotational speed of the compressor

130

is increased and reduced. Even when the engine

10

is operated, if the solenoid clutch

170

is turned off, the compressor

130

can be operated by driving the motor

120

in the inverse rotational direction, as in the stop of the engine

10

.

As described above, since the SP motor is used as the motor

120

, the planetary gear

150

can be efficiently disposed in the space of the rotor

120

a

, thereby reducing the size of the hybrid compressor

101

. Further, the pulley rotational shaft

111

, the motor

120

and the compressor rotational shaft

131

are connected to the planetary carriers

152

, sun gear

151

and the ring gear

153

, respectively. Therefore, a speed reduction ratio of the compressor

130

relative to the motor

120

can be made larger, and the motor

120

can have a high rotational speed and a low torque, thereby reducing the size of the hybrid compressor

101

and the production cost thereof.

Further, in the second embodiment, the solenoid clutch

170

and the one-way clutch

180

are provided. Therefore, even when the engine

10

is operated, when the heat load of the refrigerant cycle system

200

is low and sufficient electric power is stored in the battery

120

, the compressor

130

can be operated by the motor

120

using electric power from the battery

20

. Thus, an operational ratio of the engine

10

can be reduced, thereby improving fuel consumption performance. In the second embodiment, the other parts are similar to those of the above-described first embodiment.

(Third Embodiment)

The third embodiment of the present invention will be now described with reference to

FIGS. 8 and 9

. As shown in

FIG. 8

, in the third embodiment, an another one-way clutch (second one-way clutch)

190

is added to the hybrid compressor

101

, as compared with the second embodiment. The second one-way clutch

190

allows the motor

120

to rotate only in the inverse rotational direction from the rotational direction of the pulley

110

. The second one-way clutch

190

is disposed between the rotor portion

120

a

of the motor

120

and the housing

140

.

In the third embodiment, the operation of the hybrid compressor

101

is different from the second embodiment in the normal cooling mode after the cool down mode, among the cool down mode, the normal cooling mode after the cool down mode, the cooling mode in the stop of the engine

10

and the cooling mode in the operation of the engine

10

. As shown by the straight line G in

FIG. 9

(corresponding to the straight line G in FIG.

7

), in the above-described second embodiment, the motor

120

and the compressor

130

are operated by the driving force of the pulley

110

. However, in the third embodiment, as shown by the straight line I in

FIG. 9

, the motor

120

is locked and stopped by the second one-way clutch

190

in the rotational direction of the pulley

110

. Therefore, all of the driving force of the pulley

110

can be transmitted to the compressor

130

, and the rotational speed of the compressor

130

is increased with respect to the rotational speed of the pulley

110

.

Accordingly, driving force for driving the motor

120

to generate electric power is not required, the load of the engine

10

is reduced, thereby improving fuel consumption performance. Further, since the motor

120

does not perform power generation, control for the power generation is not required. Furthermore, electric power is not required from the motor

120

to the compressor

130

, and power consumption of the battery can be reduced. Even if the positions of the motor shaft

121

and the compressor rotational shaft

131

connected to the planetary gear

150

are interchanged from each other, the same operational effects as in the second embodiment can be obtained. In the third embodiment, the other parts are similar to those of the above-described second embodiment.

(Fourth Embodiment)

The fourth embodiment of the present invention will be now described with reference to

FIGS. 10-14

. In the fourth embodiment, an abnormal-operation detection function of the compressor

130

and a protection function for protecting the engine

10

are further added to the hybrid compressor device

100

, as compared with the third embodiment. As shown in

FIG. 10

, in the fourth embodiment, recess portions

150

a

and protrusion portions

150

b

are provided on an outer periphery of the ring gear

153

to which the compressor rotational shaft

131

is connected. As shown in

FIG. 11

, magnetic flux is generated between the rotor portion

120

a

and the stator portion

123

to be turned. A very small amount of magnetic flux leaks to a radial inner side of the rotor portion

120

a

, and to a radial outer side of the stator

123

. When the ring gear

153

having the recess portions

150

a

and the protrusion portions

150

b

is rotated while the magnetic flux leaks, magnetic resistance is changed at the radial inner side of the rotor portion

120

a

every passing of the recess portions

150

a

and the protrusion portions

150

b

. Then, the magnetic flux is changed in the stator

123

. Thus, an induced voltage V defined by the following formula (1) is generated between both ends of one coil

123

a

of the stator

123

.

V=N×d&PHgr;/dt

  (1)

Here, N is the number of turns of the coil

123

a

, &PHgr; is magnetic flux, and “t” is a time. The fluctuation of the induced voltage between both the ends of the coil

123

a

is calculated by a finite element method (FEM) analysis, and the calculated result is shown in FIG.

12

. As seen from

FIG. 12

, the fluctuation of the induced voltage can be determined by the control unit

160

even at a lower operational state of the compressor

130

, such as the rotational speed of 2000 rpm, that is, the lower limit level in operation of the compressor

130

.

Next, control operation for detecting the induced voltage V and for protecting the engine

10

will be described with reference to the flow diagram shown in FIG.

13

. At step S

1

, it is determined whether or not an air conditioner (A/C) is turned on. That is, at step S

1

, it is determined whether or not an air-conditioning request signal is received. When the air conditioner is turned on, that is, when the determination at step S

1

is YES, it is determined at step S

2

whether or not the engine

10

is operated. When the determination at step S

1

is NO, the control program is ended, and is repeated from a start step. When it is determined at step S

2

that the engine

10

is operated, it is determined at step S

3

whether or not the compressor

130

is required to be operated only by the motor

120

. Here, this determination standard is set based on the heat load of the refrigerant cycle system

200

. The heat load can be divided into a high heat load in the cool down mode, a middle heat load in the normal cooling mode and a low load, in this order. The compressor

130

is operated generally by the engine

10

and the motor

120

in the cool down mode, and is operated generally only by the engine

10