JPH11201196A - Electromagnetic clutch, compressor provided with electromagnetic clutch, and vehicular air conditioner provided with its compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mitigate shock under traveling of a vehicle by reducing noise generated at the time of connection of a clutch, and rapid increment of a load applied on a prime mover, simplify a structure, and reduce costs. SOLUTION: In an electromagnetic clutch provided with a driven clutch plate arranged opposing to a driving clutch plate rotated by a prime mover and an electromagnetic coil 36 for connecting the driven clutch plate to the driving clutch plate when rated voltage is applied and excited, an applying voltage control means 41 for carrying out applying-control is arranged between an electromagnetic coil 36 and a voltage source 40 for applying rated voltage so as to stepwise or continuously increase voltage to the electromagnetic coil 36 until voltage has attained the rated voltage. Since voltage applied on the electromagnetic coil 36 is gradually increased until voltage has attained the rated voltage, the driven clutch plate is gradually attracted to the driving clutch plate, the driven clutch plate is completely connected to the driving clutch plate, and thereby, shock noise generated at the time of clutch connection can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of an electromagnetic clutch of a compressor used in, for example, an air conditioner for a vehicle.

[0002]

2. Description of the Related Art FIG. 5 is a longitudinal sectional view showing an example of an electromagnetic clutch. This electromagnetic clutch 31 is provided in a compressor 8 of an air conditioner for a vehicle. It is mechanically intermittent. On a front portion of the front housing 32 of the compressor 8, a pulley 33 integrally formed with a flat drive clutch plate 34 is fixed at a fixed position.
It is rotatably supported via a bearing 38. On the other hand, a driven clutch plate 35 is rotatably arranged so as to face the drive clutch plate 34, and the driven clutch plate 35 is fixed to a shaft 37 of the compressor 8 and transmits rotational torque. An electromagnetic coil 36 is fixed to the front surface of the front housing 32 in a direction opposite to the driven clutch plate 35 so as to sandwich the drive clutch plate 34.

In the electromagnetic clutch 31 having the above structure, when the electromagnetic coil 36 is excited to form a magnetic circuit, the driven clutch plate 35 is attracted and is directly connected to the driving clutch plate 34. Thus, the rotational torque of the prime mover (not shown) is transmitted to the shaft 37 via the drive clutch plate 34 and the driven clutch plate 35. More specifically, a compressor 8 driven from a prime mover (not shown) via a belt or the like.
When the start switch is turned on by automatic control by increasing or decreasing the load or by manual operation by the occupant, the rated voltage of the battery is applied to the electromagnetic coil 36, the driven clutch plate 35 is attracted to the drive clutch plate 34, and the prime mover The rotation torque (not shown) is transmitted to the compressor 8. FIG. 5 shows a state in which the driven clutch plate 35 is attracted to the drive clutch plate 34.

[0004]

As described above, when the start switch of the conventional compressor is turned on, the rated voltage is applied to the electromagnetic coil of the electromagnetic clutch almost simultaneously with the start switch. That is, as shown in FIG. 6, when the start switch is turned on, for example, at time T1, the voltage V applied to the electromagnetic coil instantaneously increases to reach the rated voltage V0. As a result, the rotational torque of the prime mover is rapidly transmitted to the compressor, and the load on the prime mover is rapidly increased.
As a result, there is a problem that the impact of the vehicle is increased and a loud clutch connection sound that is unpleasant for the driver is generated when the clutch is connected.

[0005] In order to reduce such impact and clutch coupling noise, Japanese Utility Model Laid-Open No. 62-32231 discloses:
The following technology is disclosed. That is, a plurality of fitting recesses are provided in the drive clutch plate, elastic bodies are respectively fitted and fixed in the respective fitting recesses, each elastic body protrudes toward the driven clutch plate when the clutch is separated, and the driven clutch There is disclosed a technique in which a friction material having a friction surface which is flush with a friction surface of a drive clutch plate when pressed by a plate is provided. However, there is a problem that the structure of the electromagnetic clutch disclosed in Japanese Utility Model Laid-Open Publication No. 62-32231 is complicated and the manufacturing cost is increased.

Further, Japanese Patent Publication No. 54-42054 discloses a technique in which the voltage supplied to the electromagnetic coil is reduced stepwise to release the clutch and eliminate the need for a relay contact for releasing the clutch. Although disclosed, this technique is merely a technique for gradually reducing the rated voltage, and is significantly different from the technical idea of the present invention described later.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and can reduce the noise at the time of clutch engagement, and can alleviate the sudden increase of the load on the prime mover to reduce the impact of the vehicle. Another object of the present invention is to provide an electromagnetic clutch having a simple structure and a low cost. Further, another object of the present invention is to provide a compressor driven via the electromagnetic clutch, and a vehicle air conditioner including the compressor.

[0008]

According to an aspect of the present invention, there is provided an electromagnetic clutch, comprising: a driving clutch plate rotated by a prime mover; a driven clutch plate disposed opposite to the driving clutch plate; An electromagnetic coil for adsorbing and connecting one of the drive clutch plate and the driven clutch plate to the other when the rated voltage is applied and excited, and a voltage for applying a rated voltage to the electromagnetic coil And applying a voltage to the electromagnetic coil from the voltage source in a stepwise or continuous manner until the voltage reaches a rated voltage.

In the present invention, the voltage applied to the electromagnetic coil gradually increases over a predetermined time until it reaches the rated voltage, so that the driven clutch plate is gradually attracted to the drive clutch plate and is completely connected. Thus, the speed at which the driven clutch plate collides with the drive clutch plate can be reduced, and the load on the prime mover gradually increases. As a result, it is possible to reduce the impact noise at the time of clutch engagement and to alleviate a sudden increase in the load on the prime mover.

A specific configuration of the electromagnetic clutch includes a driving clutch plate rotated by a prime mover, a driven clutch plate disposed opposite to the driving clutch plate, and a rated clutch. An electromagnetic clutch comprising an electromagnetic coil for attracting and connecting one of the drive clutch plate and the driven clutch plate to the other when a voltage is applied and excited, wherein the electromagnetic coil and the electromagnetic coil A switch for controlling on / off of the application is provided between the power supply and a voltage source for applying the rated voltage to the electromagnetic coil, and when the switch is turned on, the voltage is applied to the electromagnetic coil to reach the rated voltage. And an application voltage control means for applying the voltage so as to increase stepwise or continuously.

Another aspect of the present invention is a compressor configured so that the power of the prime mover is transmitted to a shaft via an electromagnetic clutch, and the prime mover and the voltage source are a running engine and a battery, respectively. And a compressor configured to supply a high-temperature and high-pressure gas refrigerant to an evaporator for cooling the introduced air into cool air.

[0012]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of a vehicle air conditioner according to the present invention, and FIG. 2 is a diagram illustrating a control device (voltage application circuit of an electromagnetic coil) of an electromagnetic clutch according to the present invention.

First, the configuration of a vehicle air conditioner will be described with reference to FIG. This vehicle air conditioner 1
The air conditioning unit 2 has an indoor air inlet 6a and an outdoor air inlet 6b for respectively sucking the inside air and the outside air on the upstream side, and supplies the suction air to a plurality of locations in the vehicle compartment on the downstream side. (In the example, two) air outlets 12a and 13a are formed therein, and a casing 17 having an air passage 22 formed therein;
Fan 7 arranged on the upstream side of the inside and evaporator 3 (refrigerant evaporator) arranged on the downstream side of blower fan 7
A heater 11 disposed downstream of the evaporator 3;
An expansion valve 9 and the like are provided.

Between the outside air intake port 6a and the inside air intake port 6b, there is provided an inside / outside air switching damper 6 for switching between outside air and inside air that opens either the outside air intake port 6a or the inside air intake port 6b. I have. Also, the outlet 12a
Is a face-side outlet that blows out air from the front of the dashboard, for example. The outlet 13a is a foot-side outlet that is connected to a duct that supplies air from the lower part of the vehicle compartment, for example. In general, in a luxury car, this duct branches on the way, and each branch duct communicates with a front-side compartment and a rear-side compartment to supply air to each compartment.

The blower fan 7 is adapted to supply the inside and outside air to the outside air inlet 6.
a or suction from the inside air suction port 6b to be introduced into the casing 17, and is connected to an electric motor (not shown). The evaporator 3 is connected to a refrigerant compressor 8 by a refrigerant pipe.
When compressed, the air introduced from the suction ports 6a and 6b is passed through to cool the air. Also,
The heater 11 is connected to a traveling engine 16 (motor) mounted on the vehicle by a hot water pipe.
Of cooling water is circulated inside, and the passing air is heated. The rotational torque of the traveling engine 16 is transmitted to the refrigerant compressor 8 via the pulley 14, the belt 15, and the above-described electromagnetic clutch 31 (see FIG. 5). Since the structure of the electromagnetic clutch 31 has been described above with reference to FIG. 5, its description is omitted here.

An air mix damper 10 pivotally supported by a casing 17 is provided in the vicinity of the upstream side of the heater 11 so as to be swingable. It can be adjusted from a state in which the air flow into the heater 11 is completely stopped by completely covering the heater 11a to a state in which the upstream surface 11a is fully opened and the air is guided to the heater 11. A temperature-controlled air outlet switching damper 12 is provided on the downstream side of the heater 11, and the temperature-controlled air outlet switching damper 12, depending on its swinging position, transfers the temperature-controlled air generated by the heater 11 to both the air outlets 12a, 12a. 1
3a. The outlet 13a is provided with a damper 13 for adjusting the opening area.

The sensors 5 are composed of an outside air temperature sensor 18 for detecting the outside air temperature, a solar irradiation sensor 19 for detecting the amount of solar radiation, and an inside air temperature sensor 20 for detecting the temperature of a representative point in the vehicle compartment. The signal is supplied to the control device 4. A switch panel 21 is connected to the control device 4 in addition to the sensors 5. The control device 4 is installed in the air conditioning unit 2 by a control method in which a proportional control based on a detection value from the inside air temperature sensor 20 and a prediction control based on each detection value of the outside air temperature sensor 18 and the solar radiation sensor 19 are added. The rotation speed of the blower fan 7 and the opening degree of the air mix damper 10 are automatically controlled so that the temperature of the vehicle occupant is set from the switch panel 21.

The evaporator 3 (refrigerant evaporator) and the expansion valve 9 are composed of a refrigerant compressor 8, a refrigerant condenser 24 (condenser).
A refrigerant circuit is constituted by the refrigerant receiver 25 (receiver). The high-temperature and high-pressure gas refrigerant discharged from the refrigerant compressor 8 enters the refrigerant condenser 24, where it is condensed and liquefied by radiating heat to outside air. The liquid refrigerant enters the refrigerant receiver 25, where the uncondensed gas refrigerant is separated from the liquid refrigerant. The liquid refrigerant flowing out of the refrigerant receiver 25 is supplied to the expansion valve 9.
And adiabatic expansion by being squeezed here
It becomes a low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant enters the evaporator 3, evaporates by cooling the room air, and is then sucked into the refrigerant compressor 8 as a low-temperature and low-pressure gas refrigerant.

Here, the characteristic portion of the vehicle air conditioner of the present embodiment will be described. As described above, the rotational torque of the traveling engine 16 is transmitted to the refrigerant compressor 8 via the pulley 14, the belt 15, and the above-described electromagnetic clutch 31 (see FIG. 5), and the refrigerant compressor 8 Turn on / off by the start switch so that the indoor temperature becomes the set temperature.
Controlled off. That is, as shown in FIG. 2, a start switch 39 of the refrigerant compressor 8 and an applied voltage control unit 41 described later are provided between the battery 40 (DC voltage source) of the vehicle and the electromagnetic coil 36. Electromagnetic clutch 31
The rated voltage is applied to the electromagnetic coil 36 by the battery 40 of the vehicle when the start switch 39 is turned on. In the present embodiment, as shown in FIG. 2 and FIG. 3, the electromagnetic coil 36 is turned on for a predetermined time (T2−T1) from the time when the start switch 39 is turned on (see time T1). And an application voltage control means 41 for applying a voltage (see a broken line 42 and a dashed line 43) so as to increase stepwise or continuously until the rated voltage V0 is reached.

More specifically, as indicated by reference numeral 42, when the start switch 39 is turned on (time T1), the applied voltage control means 41 applies the rated voltage V to the electromagnetic coil 36 first.
For example, a half of 0 is marked and a predetermined time (for example, 0.1 seconds)
After the lapse of time, by controlling so as to apply the rated voltage V0, the driven clutch plate 35 shown in FIG. The driven clutch plate 35 is sucked and semi-fixed (semi-coupled), and at time T2, the driven clutch plate 35
4 and is completely connected by being adsorbed with a specified adsorbing force.

As described above, since the driven clutch plate 35 is attracted to the drive clutch plate 34 in two stages, the speed at which the driven clutch plate 35 collides with the drive clutch plate 34 is reduced, and consequently, the clutch is connected. Sound is reduced. Also,
The rotational torque of the traveling engine 16 is not transmitted to the refrigerant compressor 8 abruptly, so that the sudden increase in the load on the traveling engine 16 can be reduced by almost half, and the impact on the vehicle is reduced. That is, the traveling engine 16 is moved to the shaft 37 of the refrigerant compressor.
Can be gradually increased, so that the load on the traveling engine 16 can be gradually increased, and the impact during traveling of the vehicle can be reduced. In the case of this example, as an example of the applied voltage control means 41,
As shown in FIG. 4, a circuit in which a resistor R and a switch 50 are connected in parallel can be mentioned. The start switch 39 is turned on with the switch 50 opened, and the switch 50 is closed after a predetermined time has elapsed. As a result, the time-dependent change of the voltage applied to the electromagnetic coil 36 becomes two-stage as indicated by reference numeral 42. Further, the voltage applied to the electromagnetic coil 36 is not limited to being applied in two steps, but may be applied in other steps.

Next, reference numeral 43 indicates an upwardly convex curve, and when the start switch 39 is turned on (time T1)
After the elapse of a predetermined time (for example, 1 to 2 seconds), the voltage applied to the electromagnetic coil 36 is continuously increased so as to reach the rated voltage V0. In this case, the driven clutch plate 35 shown in FIG. 5 is gradually attracted to the drive clutch plate 34 over a predetermined period of time, so that the clutch connection noise can be reduced, and the traveling of the refrigerant compressor to the shaft 37 can be reduced. Since the transmission of the rotational torque of the engine 16 can be continuously increased, the load applied to the traveling engine 16 can be continuously increased, and the impact during traveling of the vehicle can be reduced. In the case of the present example, as an example of the applied voltage control means 41, a time constant circuit including a resistor and a capacitor can be cited. In the case of this example, at the initial stage of the predetermined time, it is considered that the attraction force of the driven clutch plate 35 and the driving clutch plate 34 is small and the transmission torque of the electromagnetic clutch is small. It is preferable to control the applied voltage in accordance with the load torque. Further, the control of the applied voltage is not limited to those shown by reference numerals 42 and 43, and the voltage may be increased one-dimensionally,
It may be increased along a downwardly convex curve.

Here, an example of a method for blowing air into the vehicle compartment in the above-described vehicle air conditioner will be described. First, by driving the blower fan 7, the outside air or the inside air flows from the outside air suction port 6 a or the inside air suction port 6 b to the casing 1.
7 and is sent downstream through the air flow path 22. The introduced air then passes between the fins of the evaporator 3 to exchange heat with the refrigerant flowing in the tube of the evaporator 3 to be cooled, and is sent to the downstream heater 11 side.

At this time, when the air mix damper 10 is set so as to completely cover the upstream surface 11 a of the heater 11, the air does not pass through the heater 11 and the air flow above the air mix damper 10 does not flow. It is guided to the road and blown. Also, the air mix damper 10 is
Is set to a state in which the upstream surface 11a of the heater 11 is fully opened, the air passes through the space between the fins of the heater 11 and exchanges heat with the high-temperature cooling water flowing through the tube of the heater 11 to generate hot air. It is blown. Further, when the air mix damper 10 is disposed at an intermediate position between these states, the air is separately blown to the upper side and the lower side of the air mix damper 10, and the air guided to the lower side is While being heated by the heater 11, the air guided upward is blown as cold air.

When the cold air and the hot air join on the downstream side of the air mix damper 10, they are sent to the downstream side as mixed air having a temperature corresponding to the ratio of the two airs, and the air mix damper 10 swings. Depending on the position, the temperature of the air blown to the downstream side is adjusted. Therefore, the cold air, the hot air, or the mixed air thereof is guided to the open air outlets 12a and 13a and is blown out to the respective locations in the vehicle cabin at a predetermined air volume, thereby achieving air conditioning in the vehicle cabin. Done. In the above embodiment, the present invention is not limited to the application of the electromagnetic clutch control method of the present invention to a compressor of a vehicle air conditioner, but may be applied to a general room air conditioner compressor.

[0026]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, the voltage applied to the electromagnetic coil is controlled so as to gradually increase over a predetermined time until the voltage reaches the rated voltage, so that the driven clutch plate is gradually attracted to the drive clutch plate. Thus, the speed at which the driven clutch plate collides with the driving clutch plate can be reduced, and the load on the prime mover gradually increases. As a result, it is possible to reduce the impact noise at the time of clutch engagement and to alleviate a sudden increase in the load on the prime mover. Also,
The structure of the electromagnetic clutch is not complicated as in the related art, and the manufacturing cost is not increased.

The electromagnetic clutch according to the second aspect can easily and surely perform the applied voltage control as in the first aspect, and can provide a preferred embodiment. According to the third aspect of the present invention, the compressor used in many facilities can be driven by the electromagnetic clutch according to the present invention. The invention described in claim 4 can provide an air conditioner for a vehicle in which an occupant of the vehicle does not become uncomfortable due to an impact sound when the clutch is engaged.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a vehicle air conditioner according to the present invention.

FIG. 2 is a diagram showing a control device (a circuit for applying a voltage to an electromagnetic coil) of the electromagnetic clutch according to the present invention.

FIG. 3 is a graph showing a change over time of a voltage applied to an electromagnetic clutch according to the embodiment.

FIG. 4 is a diagram illustrating an example of an applied voltage control unit.

FIG. 5 is a longitudinal sectional view of the electromagnetic clutch.

FIG. 6 is a graph showing a change over time of a voltage applied to a conventional electromagnetic clutch.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 vehicle air conditioner 2 air conditioning unit 3 evaporator 7 blower fan 8 refrigerant compressor 10 air mix damper 11 heater 16 running engine (motor) 31 electromagnetic clutch 34 drive clutch plate 35 driven clutch plate 36 electromagnetic coil 39 start of compressor Switch 40 Vehicle battery (voltage source) 41 Applied voltage control means

Claims (4)

[Claims] 1. A drive clutch plate rotated by a prime mover, a driven clutch plate arranged opposite to the drive clutch plate, and the drive clutch plate and the driven clutch when a rated voltage is applied and excited. An electromagnetic clutch including an electromagnetic coil for adsorbing and connecting one of the plates to the other and a voltage source for applying a rated voltage to the electromagnetic coil, wherein a voltage is applied from the voltage source to the electromagnetic coil. When applying
An electromagnetic clutch wherein the voltage is increased stepwise or continuously until the rated voltage is reached. 2. A drive clutch plate rotated by a prime mover, a driven clutch plate disposed to face the drive clutch plate, and the drive clutch plate and the driven clutch when a rated voltage is applied and excited. An electromagnetic clutch comprising an electromagnetic coil for adsorbing and connecting one of the plates to the other, wherein the application is performed between the electromagnetic coil and a voltage source for applying a rated voltage to the electromagnetic coil. A switch for on / off control is provided, and when the switch is turned on, an applied voltage control for applying a voltage to the electromagnetic coil in a stepwise or continuous manner until the rated voltage is reached. An electromagnetic clutch comprising means. 3. A compressor, wherein the power of the prime mover is transmitted to a shaft via the electromagnetic clutch according to claim 1 or 2. 4. The high-pressure high-pressure gas refrigerant according to claim 3, wherein the prime mover and the voltage source are a running engine and a battery, respectively. An air conditioner for a vehicle, characterized in that the air conditioner is configured to be supplied.