JPH05262128A - Refrigerating cycle control system - Google Patents

Abstract

PURPOSE:To prevent early wear of an engagement clutch means by combining a friction transmitting mechanism with the engagement clutch means while downsizing and weight-reducing an electromagnetic clutch. CONSTITUTION:A compressor is constituted to be of variable capacity type. A pin 44 constituting an engagement clutch means 43 is supported by an armature which is integratedly rotated with a rotary shaft 17 of this compressor. A pin hole 50 is formed in a rotor 34 opposite thereto. When the compressor 2 is started, the capacity of the compressor (the driving torque) is reduced, and at the same time, the rotation of the compressor is started by making the magnetic attracting force of a magnet coil 32 smaller than the set value, thereby attracting the armature only, i.e., with the frictional transmission only. Around the time when the rotation of the compressor has been increased sufficiently, the pin 44 is also attracted and engaged with the pin hole 50 by energizing and controlling so that the magnetic attracting force of the magnetic coil 32 may be larger than the set value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle control system for controlling the operation of an electromagnetic clutch that connects and disconnects power transmission from a drive source to a compressor.

[0002]

2. Description of the Related Art In recent years, for example, in order to reduce the size and weight of an electromagnetic clutch for a compressor mounted on an automobile, a friction transmission mechanism and a pin meshing mechanism are combined as disclosed in Japanese Patent Laid-Open No. 2-26324. An electromagnetic clutch has been devised which is adapted to perform power transmission.

This electromagnetic clutch includes a magnet coil, a rotor rotated by a drive source such as an engine, and an armature which rotates integrally with a rotary shaft of a compressor.
With a pin displaceably supported by this armature,
During power transmission, the magnet coil is energized and the electromagnetic attraction force attracts the armature to the rotor side to press them together, and at the same time, the pin is also attracted to engage the pin with the pin hole of the rotor. And the rotor is locked. With this configuration, the clutch force required for power transmission can be supplemented by the meshing of small pins, so there is an advantage that the friction transmission mechanism (armature, rotor, magnet coil, etc.) can be made smaller and lighter.

[0004]

By the way, in the above-mentioned conventional structure, when the energization of the magnet coil is started, the armature is attracted to the rotor side and friction transmission is started, and at the same time, the pin is attracted to the rotor side. However, when the friction transmission starts, the pin and the pin hole are usually displaced from each other, so that even if the pin is sucked to the rotor side, the pin does not immediately engage with the pin hole, and the tip of the pin does not rotate. The rotation of the compressor is started only by friction transmission in the state of being in contact with the end surface of the compressor. At the beginning of this friction transmission, the armature starts to rotate while sliding with respect to the rotor that is rotationally driven by the drive source, so in the process, the pin meshes with the pin hole at the moment when the position of the pin and the pin hole match. ..

Therefore, since the pin and the pin hole are engaged with each other while the difference in the rotational speeds of the armature and the rotor (clutch slip) is still large, the tip of the pin violently contacts the peripheral portion of the pin hole during the engagement. There is a risk that the pins and pin holes (clutch clutch means) will be worn out at an early stage due to collision, which has been a factor that reduces durability.

The present invention has been made in view of the above circumstances, and an object thereof is to achieve early wear of the mesh clutch means while reducing the size and weight of the electromagnetic clutch by combining the friction transmission mechanism and the mesh clutch means. Another object of the present invention is to provide a refrigeration cycle control system capable of preventing the above and improving the durability.

[0007]

A refrigeration cycle control system according to the present invention controls the operation of an electromagnetic clutch that connects and disconnects power transmission from a drive source to a compressor, wherein the compressor is of a variable displacement type. ,
The electromagnetic clutch, a rotor rotated by the drive source, an armature that rotates integrally with the rotation shaft of the compressor, a magnet coil that attracts the armature to the rotor side when energized to frictionally transfer power, And a meshing clutch means that is attracted so that the armature and the rotor are locked when the magnetic attraction force of the magnet coil exceeds a set value.
When the compressor is started, the capacity of the compressor is reduced and the energization of the magnet coil is controlled so that the magnetic attraction force is equal to or less than the set value, so that only the armature is attracted and only the friction transmission is performed. The rotation of the compressor is started, and thereafter, the energization to the magnet coil is controlled so that the magnetic attraction force exceeds the set value, so that the dog clutch means is also attracted.

[0008]

According to the above-mentioned structure, when the compressor is started, the capacity of the compressor is reduced so that the torque required for driving the compressor (driving torque) is reduced. In this state, the energization of the magnet coil is controlled so that the magnetic attraction force becomes less than the set value, so that the armature is attracted and the compressor is rotated only by friction transmission without operating the dog clutch mechanism. Launch.
At this time, since the capacity (driving torque) of the compressor is small, a sufficient clutch force can be secured only by friction transmission, and the rotation of the compressor can be quickly started.

After that, when the rotation of the compressor has risen to some extent, energization to the magnet coil is controlled so that its magnetic attraction force exceeds a set value, and the dog clutch means is also attracted. After this, even if the capacity (driving torque) of the compressor is increased, the clutch force necessary for the power transmission can be supplemented by the dog clutch means, so that clutch slip does not occur and the armature, rotor, The size and weight of magnet coils can be reduced.

In this case, when the meshing clutch means is meshed, the rotation of the compressor rises to some extent, and the difference between the rotation speeds of the armature and the rotor is sufficiently small (or almost completely eliminated). The meshing operation is smoothly performed without causing a large impact as in the conventional case, and early wear of the meshing clutch means is prevented.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a vehicle air conditioner will be described below with reference to the drawings. First, a schematic configuration of the entire system will be described with reference to FIG. The refrigeration cycle 1 is configured by sequentially connecting the discharge port 2a of the compressor 2, the condenser 3, the receiver 4, the expansion valve 5, the cooler 6, and the suction port 2b of the compressor 2. As a result, the high-temperature and high-pressure gas refrigerant discharged from the discharge port 2a of the compressor 2 radiates heat in the condenser 3 and is liquefied, and is gas-liquid separated by the receiver 4, and then the liquid refrigerant passes through the expansion valve 5 to cool the cooler. 6 is supplied. In the process of passing through the cooler 6, this liquid refrigerant exchanges heat with the air in the vehicle to be gasified, and is sucked into the compressor 2 through the suction port 2b. A fan 7 is attached to the cooler 6,
The fan 7 cools the interior of the vehicle by sending cool air into the interior of the vehicle.

On the other hand, the compressor 2 is rotationally driven by the power of the engine 8 which is a drive source. The power transmission path transmits the rotation of the crankshaft pulley 9 of the engine 8 to the compressor 2 via the belt 10 and an electromagnetic clutch 11 described later. Then, the operation of the compressor 2 (electromagnetic clutch 11) and the fan 7 is controlled by the control circuit 14 based on the output signal of the temperature sensor 12 for detecting the cold air blowing temperature and the operation input from the operation unit 13 as described later. ..

In this case, the compressor 2 is composed of a so-called swash plate type variable displacement compressor, and as shown in FIG.
The reciprocating motion is made in 8 to suck, compress, and discharge the refrigerant. The mechanism for changing the capacity of the compressor 2 changes the stroke L of the piston 15 by changing the inclination angle of the swash plate 16. The swash plate 16 has a support portion 1 having an inclined groove 17.
6a is integrally formed, and the swash plate 16 is connected to the rotary shaft 17 of the compressor 2 by fitting the inclined groove 17 and the pin 18. The relative positional relationship between the inclined groove 17 and the pin 18 changes as the inclination angle of the swash plate 16 changes.

Next, the mechanism for adjusting the inclination angle of the swash plate 16 will be described. The swash plate 16 is swingably supported by a ball 20 fixed to the front end of the rear shaft 19. A spool 21 is attached to the rear end side of the rear shaft 19, and the pressure in the working chamber 22 of the spool 21 is changed to change the pressure of the spool 21 and the rear shaft 1.
9 is integrally slid to adjust the inclination angle of the swash plate 16.

The pressure in the working chamber 22 is controlled by the capacity switching valve 2
By the switching of 3, the control is performed as follows. That is, when the capacity of the compressor 2 is reduced, the compressor 2
The low-pressure refrigerant gas is introduced into the working chamber 22 through the low-pressure introduction passage 25 communicating with the refrigerant suction chamber 24 in the working chamber 2
By lowering the internal pressure of 2, the spool 21 and the rear shaft 19 are retracted to the right in FIG. 2 to reduce the inclination angle of the swash plate 16 and the stroke L of the piston 15. On the other hand, when increasing the capacity of the compressor 2, the low pressure introduction passage 25 is shut off, and high pressure refrigerant gas is introduced into the working chamber 22 through the high pressure introduction passage 27 communicating with the refrigerant discharge chamber 26. 2 is advanced to move the spool 21 and the rear shaft 19 leftward in FIG. 2 to increase the inclination angle of the swash plate 16 and increase the stroke L of the piston 15.

Next, the structure of the electromagnetic clutch 11 will be described with reference to FIGS. An annular stator 31 is attached to the housing 29 of the compressor 2 via an attachment flange 30, and the annular recess 31 a of the stator 31 is attached.
A magnet coil 32 is molded inside with an epoxy resin 33. The rotor 34 facing the stator 31 is rotatably attached to the housing 29 of the compressor 2 via a bearing 35. A pulley 36 is integrally formed on the outer peripheral portion of the rotor 34.
And the crankshaft pulley 9 of the engine 8 (see FIG. 1)
The belt 10 is stretched between the and.

On the other hand, a circular hub 37 is fastened and fixed to the tip of the rotary shaft 17 of the compressor 2 with bolts 38. The hub 37 is provided with, for example, three leaf springs 39 as shown in FIG. It is fixed via rivets 40. An annular armature 41 is fixed to the three leaf springs 39 via rivets 42, and the armature 41 faces the friction surface 34a of the rotor 34 via a predetermined gap. ..

To this armature 41, for example, three meshing clutch means 43 are supported as follows. That is, the dog clutch means 43 is configured by joining the outer end of the pin 44 made of a non-magnetic material with the suction portion 45 made of a highly magnetic material by press fitting or the like, and the pin 44 is inserted into the through hole 46 formed in the armature 41. It is penetrated from the outside. A spring 47 is mounted between the suction portion 45 and the armature 41, and the elastic force of the spring 47 urges the pin 44 outward. A stopper plate 48 is fixed to the armature 41 by a bolt 49 as a means for preventing the pin 44 from coming off. When the electromagnetic clutch 11 is off, as shown in FIG. 3, the attracting portion 45 is in contact with the stopper plate 48 by the elastic force of the spring 47 (the tip of the pin 44 does not project from the through hole 46 to the rotor 34 side). ) Is held.

Corresponding to the pin 44, a pin hole 50 is formed in the friction surface 34a of the rotor 34. In order to smoothly fit the pin 44 into the pin hole 50, a tapered guide surface 50a is formed on the inlet side peripheral edge of the pin hole 50 as shown in FIG. 7, and as shown in FIG. A radius R is formed at the tip of the pin 44.

The control circuit 14 for controlling the operation of the electromagnetic clutch 11 having such a structure is constituted by, for example, a microcomputer, and when the compressor 2 is started, the magnet coil 32 is energized and the compressor 2 is operated in accordance with the start control routine shown in FIG. Controls the capacity switching operation. Less than,
The control contents at the time of starting are shown in the flowchart of FIG. 9 and FIG.
This will be explained with reference to the time chart of.

When the user turns on the air conditioner switch (not shown) of the operation unit 13, the start-up control routine of FIG. 9 starts, and first, the capacity of the compressor 2 is minimized as follows (step S1). ). That is, the capacity switching valve 23 of the compressor 2 shuts off the high pressure introduction passage 27, and the low pressure refrigerant gas is introduced into the working chamber 22 through the low pressure introduction passage 25 communicating with the refrigerant suction chamber 24.
By lowering the internal pressure of 2, the spool 21 and the rear shaft 19 are retracted to the right in FIG. 2, and the inclination angle of the swash plate 16 is reduced. As a result, the stroke L of the piston 15 is minimized and the capacity of the compressor 2 is minimized.

Next, the applied voltage of the magnet coil 32 is set to a low voltage VLo so that the magnetic attraction force becomes less than a set value.
(For example, 6 V) (step S2). The set value is the spring 4 for urging the dog clutch means 43.
7 is a value corresponding to the magnitude of the elastic force, and the magnetic attraction force is set to a value less than or equal to the set value (elastic force of the spring 47). The rotor 34 resists the elastic force of the spring 39.
It is sucked to the side to bring them into pressure contact with each other and generate a pressure contact frictional force between them. As a result, the power of the engine 8 is transferred to the belt 10
→ rotor 34 → armature 41 → leaf spring 39 → hub 37
The rotation is transmitted to the rotary shaft 17 of the compressor 2 through the path, and the rotation of the compressor 2 is started only by the friction transmission by the pressure contact between the rotor 34 and the armature 41.

In this case, since the compressor 2 has the smallest capacity and the driving torque is small, even if the applied voltage (magnetic attraction force) to the magnet coil 32 is small, as shown in FIG.
As indicated by 0, the rotation of the compressor 2 can be quickly started only by friction transmission. Since the pin 44 of the dog clutch means 43 is supported by the armature 41, when the armature 41 is sucked, it moves integrally with the armature 41 as shown in FIG.
The tip end of is kept slightly submerged in the through hole 46 of the armature 41 and does not hit the friction surface 34a of the rotor 34.

The power transmission by such friction transmission is continued for a predetermined time T1 (step S3). Here, the predetermined time T1 is the time until the rotation of the compressor 2 (armature 41) rises sufficiently to match the rotation speed of the rotor 34 (time until slippage between the armature 41 and the rotor 34 disappears). The time is set to the same level or a little longer than that, and is appropriately set at the designing stage in consideration of the capacity and load of the compressor 2 in advance.

After the elapse of the predetermined time T1, the applied voltage of the magnet coil 32 is set to the high voltage VHi (for example, 12V) so that the magnetic attraction force exceeds the set value (step S4). Thereby, the suction portion 45 of the clutch means 43
The magnetic attraction force acting on the pin 47 overcomes the elastic force of the spring 47, the engagement clutch means 43 is attracted, and the pin 4
4 protrudes from the through hole 46 of the armature 41 to the rotor 34 side. At this point, the positions of the pin 44 and the pin hole 50 are usually displaced from each other, so that the pin 44 does not immediately engage with the pin hole 50 even if sucked by the rotor 34 side, and the pin 44 does not move. Friction surface 3 of rotor 34
In the state of being in contact with 4a, power is transmitted only by friction transmission for a while. The friction transmission force at this time is increased from the beginning by setting the applied voltage of the magnet coil 32 to the high voltage VHi.

Thereafter, the capacity of the compressor 2 is increased according to the heat load (step S5). Specifically, the capacity of the compressor 2 is variably controlled so that the temperature detected by the temperature sensor 12 matches the set temperature. When the capacity of the compressor 2 is increased, the capacity switching valve 23 shuts off the low pressure introduction passage 25. Then, high-pressure refrigerant gas is introduced into the working chamber 22 through the high-pressure introducing passage 27 communicating with the refrigerant discharge chamber 26, and the internal pressure of the working chamber 22 is increased, so that the spool 21 and the rear shaft 19 are moved to the left in FIG. To increase the tilt angle of the swash plate 16 to the piston 1
5 stroke L is increased. On the other hand, the compressor 2
When the capacity of the piston 15 is reduced, as described above, the capacity switching valve 23 shuts off the high-pressure introduction passage 27 and opens the low-pressure introduction passage 25 to reduce the internal pressure of the working chamber 22. To reduce.

At this time, when the capacity of the compressor 2 increases and the driving torque exceeds a certain value, the clutch force required for power transmission is insufficient only by friction transmission between the armature 41 and the rotor 34 by the pressure contact friction force. Then, Armacha 41
Slippage occurs between the rotor and the rotor. As a result, at the moment when the positions of the pin 44 and the pin hole 50 are matched (T2 in FIG. 10), the pin 44 meshes with the pin hole 50, and the armature 41 and the rotor 34 are locked. After that, even if the capacity (driving torque) of the compressor 2 is increased, the clutch force required for power transmission can be supplemented by the engagement between the pin 44 and the pin hole 50, so that clutch slippage occurs. Instead, the armature 41, the rotor 34, the magnet coil 32, etc. can be made smaller and lighter.

In this case, when the pin 44 is engaged with the pin hole 50, there is some slippage between the armature 41 and the rotor 34, and the armature 41 and the rotor 34 are slightly slipped.
Since the difference in the number of rotations is sufficiently small (or almost eliminated), the engagement between the pin 44 and the pin hole 50 is smoothly performed without a large impact as in the conventional case, and the pin 44 and the pin Premature wear of the hole 50 is prevented and durability is improved.

During the cooling operation, the capacity of the compressor 2 is variably controlled according to the difference between the temperature detected by the temperature sensor 12 and the set temperature as described above.
When the user turns off the air conditioner switch, step S6
In step S7, the capacity of the compressor 2 is minimized, the power supply to the magnet coil 32 is turned off (step S8), and the armature 41 is moved by the elastic force of the leaf spring 39. While separating from the rotor 34, the pin 44 is pulled out from the pin hole 50 by the elastic force of the spring 47, the power transmission is interrupted, and the operation of the compressor 2 is stopped.

At the time of this operation stop, it is not always necessary to minimize the capacity of the compressor 2, and when the air conditioner switch is turned off, the process of step 7 is omitted,
It goes without saying that the electromagnetic clutch 11 may be turned off immediately.

Further, the compressor 2 is not limited to the swash plate type variable displacement compressor as in the present embodiment. For example, a bypass passage is provided between the discharge side and the suction side, and the flow rate of the refrigerant flowing in the bypass passage is set. It may be a variable capacity compressor of a bypass type in which the refrigerant discharge amount is controlled by controlling, or a transmission is provided in the power transmission path to the compressor, and the rotation speed of the compressor is changed by this transmission. It may be a variable displacement compressor of a variable speed type in which the refrigerant discharge amount is changed. Further, it may be a variable capacity compressor of a system in which the compression action of some of the plurality of cylinders is stopped to change the refrigerant discharge amount. In short, it is sufficient if the capacity of the compressor can be adjusted continuously or stepwise, and if the capacity changes stepwise, the capacity change is not limited to three or more steps, but at least two steps. If so, the present invention can be applied.

On the other hand, the meshing clutch means 43 is not limited to the one using the pin 44, and may be one using a tooth. In short, the meshing clutch means 43 is configured to transmit power by utilizing the meshing of the members. Good.

In this embodiment, the magnet coil 3 is used.
Although the applied voltage is changed in order to change the magnetic attraction force of No. 2, it goes without saying that the applied current or the applied rate to the magnet coil 32 may be changed. Further, in the present embodiment, the timing T1 at which the dog clutch means 43 is sucked at the time of startup is set after the slippage between the armature 41 and the rotor 34 is completely eliminated. After that, the dog clutch means 43 may be sucked at a timing earlier than the timing T1 of the present embodiment. Even in this case, the difference in the rotational speed between the armature 41 and the rotor 34 is sufficiently small, The engaging operation of the pin 44 and the pin hole 50 is smoothly performed without a large impact as in the conventional case, and the early wear of the pin 44 and the pin hole 50 is prevented.

Further, in this embodiment, the capacity of the compressor 2 is increased at the same time when the dog clutch means 43 is sucked, but it is not always necessary to immediately increase the capacity of the compressor 2 when the heat load is small. After that, the capacity of the compressor 2 may be increased when the heat load increases.

In addition, the present invention is not limited to an air conditioner for an automobile, but can be widely applied to equipment provided with an electromagnetic clutch for connecting and disconnecting power transmission to a compressor, and various modifications can be made without departing from the scope of the invention. Is.

[0036]

As is apparent from the above description, according to the present invention, when the compressor is started, the capacity of the compressor is reduced and the magnetic attraction force of the magnet coil is set to the set value or less so that only the armature is attracted. The rotation of the compressor is started only by friction transmission, and thereafter, the magnetic attraction force of the magnet coil is made larger than the set value so that the meshing clutch means is also attracted, so that the clutch force required for power transmission is reduced. ,
It can be supplemented by the dog clutch means, the armature, the rotor, the magnet coil, etc. can be made smaller and lighter, and the dog clutch means can smoothly perform the dog clutch operation, thereby preventing early wear of the dog clutch means. , The durability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an entire system showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a variable displacement compressor.

FIG. 3 is a sectional view of the electromagnetic clutch taken along line III-III in FIG.

FIG. 4 is a front view of the electromagnetic clutch.

FIG. 5 is a front view of the rotor

FIG. 6 is a front view of the armature.

FIG. 7 is a sectional view of the pin hole portion taken along the line VII-VII in FIG.

FIG. 8 is a sectional view of a dog clutch unit.

FIG. 9 is a flowchart of a startup control routine.

FIG. 10 is a time chart showing the operation timing of each part.

[Explanation of symbols]

1 is a refrigeration cycle, 2 is a compressor, 8 is an engine (driving source), 11 is an electromagnetic clutch, 14 is a control circuit, 1
5 is a piston, 16 is a swash plate, 17 is a rotating shaft, 24 is a capacity switching valve, 31 is a stator, 32 is a magnet coil, 3
4 is a rotor, 34a is a friction surface, 36 is a pulley, 37 is a hub, 39 is a leaf spring, 41 is an armature, 43 is a meshing clutch means, 44 is a pin, 45 is a suction part, 47 is a spring, 48 is a stopper plate, 50 is a pin hole.

Claims (1)

[Claims] 1. A rotor for controlling the operation of an electromagnetic clutch that connects and disconnects power transmission from a drive source to a compressor, wherein the compressor is of a variable displacement type, and the electromagnetic clutch is rotated by the drive source. An armature that rotates integrally with the rotary shaft of the compressor; a magnet coil that attracts the armature to the rotor side when energized to frictionally transmit power; and a magnetic attraction force by the magnet coil exceeds a set value. When the compressor is started, the capacity of the compressor is reduced, and the magnet coil is energized by magnetizing the armature and the rotor. By controlling the suction force so that it is less than the set value, the armature And the clutch clutch means is also attracted by controlling the energization to the magnet coil so that the magnetic attraction force exceeds the set value. A refrigeration cycle control system having the above structure.