JP2000220662A - Rotary machine with electromagnetic clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the discharging effect of brush abrasion powder in a coil rotary type electromagnetic clutch. SOLUTION: A first air passage 30 extended in the axial direction is formed up in the outer circumferential side of a cylindrical shaped boss part 6a provided for the housing 6 of a compressor 5, one end side of the first air passage 30 is communicated with the peripheries of the sliding parts of slip rings 19 and 20 with brushes 22 and 23, and the other end side of the first air passage 30 is released outside by means of a suction port 31. A first blast fan 36 is formed up in a slip ring holding member 18 held by a rotor 1, air is sucked in from the first air passage 30 by the first blast fan 36, after sucked air has passed the periphery of the sliding part, it is discharged outside through the through hole 34 of the slip ring holding member 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating machine with an electromagnetic clutch for intermittently transmitting power, and is suitable as a compressor for a refrigeration cycle of an air conditioner for a vehicle.

[0002]

2. Description of the Related Art Conventionally, as an electromagnetic clutch used in a compressor of an air conditioner for a vehicle, a coil rotary type in which an electromagnetic coil is installed on a rotating member side is disclosed in Japanese Utility Model Laid-Open No. 1-131028, Japanese Utility Model Laid-Open No. 2-54928, and the like. Has been proposed.
In these coil-rotating types, the magnetic circuit can be constituted only by the rotating member and the armature magnetically attracted to the rotating member, so that the magnetic loss becomes very small as compared with the coil fixed type, and the magnetic efficiency can be greatly improved. There is an advantage.

[0003]

However, in the former publication, a current-carrying member, such as a slip ring or a brush, for energizing the rotating electromagnetic coil is arranged on the side of the electromagnetic coil portion in the axial direction. As a result, the axial dimension of the electromagnetic clutch increases, making it difficult to mount the electromagnetic clutch in a narrow space such as a vehicle engine room. In addition, since the brush is located at a position where the distance (radius) from the rotation center of the electromagnetic clutch is relatively large, there is a problem that the peripheral speed of sliding on the brush surface is increased and the life of the brush is shortened. .

In the latter publication, a current-carrying member such as a slip ring or a brush is disposed further axially outward from the tip of the rotating shaft of a driven device such as a compressor. There is a problem that the axial dimension of the electromagnetic clutch increases. Therefore, the present inventors have disclosed in Japanese Patent Application No.
No. 239028 proposes an electromagnetic clutch which is of a coil rotation type and which can reduce the axial dimension and improve the brush life.

According to the prior application, in an electromagnetic clutch applied to a rotary machine such as a compressor having a rotary shaft disposed at the center of a cylindrical boss of a housing, a cylindrical boss of the rotary machine housing is provided. Paying attention to the peripheral space, a sliding energizing mechanism including a slip ring and a brush that is pressed against the slip ring is disposed at a position on the inner peripheral side of the boss portion, and the rotating member side is passed through the sliding energizing mechanism. The electromagnetic coil is energized.

According to this prior application, since the sliding energizing mechanism is located on the inner peripheral side of the boss portion, the coil energizing path can be formed with almost no increase in axial dimension even in the case of a coil rotary type clutch. it can. Therefore, the electromagnetic clutch can be easily mounted even in a narrow space such as a vehicle engine room. In addition, since the slip ring and the brush can be arranged at a position where the distance (radius) from the rotation center of the electromagnetic clutch is small, the sliding peripheral speed on the brush surface is reduced, and the life of the brush can be improved.

In the prior application, the rotating member further includes a ventilation port for discharging air around the sliding portion between the slip ring and the brush, and a blade section for generating an airflow passing through the ventilation port. Accordingly, it has been proposed to discharge brush abrasion powder to the outside of the rotating member together with the air flow. This aims to prevent problems caused by brush abrasion powder, for example, problems such as short circuit between positive and negative slip rings.

However, when a prototype of the prior application is actually evaluated, a suction passage for sucking air inside the rotating member is not specially provided. Air is sucked into the rotating member through a gap between the armature and the like. Therefore, there is a problem that the amount of air blow is very small and the brush abrasion powder cannot be sufficiently discharged.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a rotating machine having a coil rotating type electromagnetic clutch, which is capable of satisfactorily discharging abrasion powder of a brush for energizing an electromagnetic coil on a rotating member side. And

[0010]

In order to achieve the above object, according to the present invention, the rotating machine (5)
Cylindrical boss (6) provided in the housing (6)
A first air passage (30) extending in the axial direction is formed on the outer peripheral side of a), and one end of the first air passage (30) is formed by a slip ring (19, 20) and a brush (22, 23). The other end of the first air passage (30) communicates with the periphery of the sliding portion, and the other end of the first air passage (30) is open to the outside. The first air blowing means (36) rotates together with the rotating member (1). ), Air is sucked in from the first air passage (30), and the suctioned air is discharged to the outside after passing around the sliding portion.

According to this, air is forcibly forced near the sliding portion between the slip rings (19, 20) and the brushes (22, 23) by the blowing action of the first blowing means (36) rotating together with the rotating member (1). Can be blown out. In this case, the first air passage (30) can easily secure a necessary passage cross-sectional area by using the outer diameter of the boss (6a).
It is easy to secure the amount of air blown to the vicinity of the sliding portion, and it is possible to enhance the effect of discharging the brush abrasion powder.

Further, since the first air passage (30) is formed on the outer peripheral side of the boss portion (6a), a drilling process (cutting process) is specially added for forming the first air passage (30). When the housing (6) including the boss portion (6a) is formed of a metal such as aluminum, the first air passage (30) can be easily formed at the same time, so that the clutch manufacturing cost can be reduced. It is advantageous for.

Specifically, the present invention includes a slip ring (19, 20) and a brush (22, 23) at a portion on the inner peripheral side of the boss portion (6a). A sliding energizing mechanism is arranged. According to this, similarly to the above-mentioned prior application, the coil energizing path can be formed while suppressing an increase in the axial dimension even in the case of the coil rotation type clutch. In addition, since the brush can be arranged close to the center of rotation of the clutch, the sliding peripheral speed on the brush surface is reduced, and the life of the brush can be improved.

According to a third aspect of the present invention, in the electromagnetic clutch, the rotating member (1) is rotatably supported on the outer peripheral surface of the boss (6a) via the bearing (7).
The air passage (30) can be formed in a groove shape extending in the axial direction on the outer peripheral surface of the boss (6a).
According to this, even when the bearing (7) is arranged on the outer peripheral surface of the boss (6a), the first air passage (30) can be easily formed by forming the concave groove on the outer peripheral surface of the boss. .

In the invention according to claim 4, the slip ring (19, 20) is connected to the slip ring holding member (1).
8) that the rotating member (1) is held by the rotating member (1), and the slip ring holding member (18) is provided with a ventilation port (34) for discharging air around the sliding portion to the outside and a first blowing means (36). Features. According to this, by using the slip ring holding member (18), the ventilation port (34) and the first
The blowing means (36) can be easily formed.

According to the fifth aspect of the present invention, the rotating member is a driving-side rotating member (1) that rotates by receiving a driving force from a driving source, and is driven by a rotating shaft (13). A rotating member (11), the armature (8) is connected to the driven side rotating member (11) via an elastic connecting member (9), and the inner peripheral portion of the slip ring holding member (18) and the driven side rotating member ( 11) and the outer periphery of the second air passage (3).
3) is formed, and external air flows around the sliding portion through the second air passage (33).

According to this, in addition to the inflow air from the first air passage (30), the inflow air from the second air passage (33) can flow around the sliding portion, so that the brush abrasion powder can be removed. The discharge effect can be further enhanced. Further, the slip ring holding member (18) is provided with a second blowing means (37) for blowing external air toward the periphery of the sliding portion through the second air passage (33). With this, the air flowing around the sliding portion through the second air passage (33) can be increased by the blowing action of the second blowing means (37).

Further, as in the invention according to claim 7, the slip ring holding member (18), the first blowing means (36),
If the second air blowing means (37) is integrally formed of resin, these elements can be easily formed by integrally forming the resin, and the clutch manufacturing cost can be further reduced. In addition, the code | symbol in the parenthesis of each said means shows the correspondence with the concrete means of embodiment mentioned later.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show a first embodiment of the present invention, in which 1 is a driving-side rotor, and a multiple V
A pulley portion 1a having multiple V-grooves with which the belt is engaged is provided integrally.

The driving-side rotor 1 is a driving-side rotating member that rotates by receiving a rotational force from an automobile engine via a belt (not shown), and is made of an iron-based metal (ferromagnetic material) such as low-carbon steel. It is formed in the shape of a double ring having a U-shape. An annular concave portion 1d is formed between the inner cylindrical portion 1b and the outer cylindrical portion 1c of the drive side rotor 1.
A friction surface 1e is formed on a radial side surface of the rotor 1.

Reference numeral 2 denotes an electromagnetic coil for generating an electromagnetic attractive force.
It is installed in the concave portion 1 d of the driving-side rotor 1. The electromagnetic coil 2 is insulated and fixed to the concave portion 1d by a resin member 3 molded in the concave portion 1d. Therefore, the electromagnetic coil 2 rotates integrally with the drive-side rotor 1. Reference numeral 4 denotes a friction plate made of an iron-based metal (ferromagnetic material) such as low-carbon steel, and has a substantially ring shape.
Are held and fixed between the inner cylindrical portion 1b and the outer cylindrical portion 1c.

5 is a compressor (rotary machine) which is a driven device.
Reference numeral 6 denotes a front housing located on the electromagnetic clutch side of the compressor 5. The front housing 6 is made of an aluminum-based metal, and has a boss 6a that protrudes in a cylindrical shape outward in the axial direction and is integrally formed at the center. Here, the compressor 5 is for compressing a refrigerant in a refrigeration cycle of an air conditioner for a vehicle, and may be any type such as a known swash plate type, a vane type, and a scroll type.

Reference numeral 7 denotes a bearing for rotatably supporting the driving rotor 1 on the boss 6a of the front housing 6. In this embodiment, the bearing 7 includes an outer ring 7a fixed to the inner peripheral surface of the driving rotor 1. Inner ring 7 fixed to the outer peripheral surface of boss 6a
and a ball bearing 7b rotatably held between the two 7a and 7b.

Reference numeral 8 denotes the friction surface 1e of the rotor 1 and the friction plate 4
The armature is disposed opposite to the armature, and is formed of an iron-based metal (ferromagnetic material) in a ring-shaped flat plate shape. When the electromagnetic coil 2 is not energized, the armature 8 serves as the friction surface 1 of the rotor 1.
e and a position at a predetermined minute distance from the friction plate 4 (FIG. 1)
(Position shown in FIG. 3) by the spring force of the leaf spring (elastic connecting member) 9.

The leaf springs 9 are elongated and thin plate-shaped, and a plurality of leaf springs 9 are arranged in the circumferential direction of the armature 8. One end of each leaf spring 9 is connected to the hub 11 by a rivet 10. Is connected to the armature 8 by another rivet (not shown). The hub 11 is a driven-side rotating member and is formed of a ferrous metal into a shape having a plate-like portion 11a extending in the radial direction and a central cylindrical portion 11b.

At the outer peripheral portion of the plate-like portion 11a of the hub 11, stopper members 12 made of an elastic material such as rubber are mounted at a plurality of positions in the circumferential direction, and when the clutch is disconnected (when the coil is not energized). ) Defines the axial position of the armature 8. Further, the armature 8 is pressed in the axial direction (toward the rotor 1) by the thickness of the stopper member 12 from the surface of the plate-shaped portion 11a, and the leaf spring 9 is elastically deformed. A force is generated, and the spring force holds the armature 8 at a predetermined axial position when the clutch is disconnected.

The center cylindrical portion 11b of the hub 11 is
And is fitted to the rotating shaft 13 by a spline connection or the like. And the tip male screw part 13a of the rotating shaft 13
The nut 11 is screwed into the hub 11 to rotate the hub 11
3 is integrally connected. Next, a description will be given of a configuration of an energizing path to the electromagnetic coil 2 that rotates together with the rotor 1. In the present embodiment, the brushes 22 and 23 arranged at the inner peripheral side of the compressor boss 6a supporting the bearing 7 are described. And the brushes 22, 23 constitute a sliding energizing mechanism having slip rings 19, 20 on which the brushes 22 and 23 are pressed and slid.

The layout of the sliding energizing mechanism is specifically configured as follows. Recess 1 of rotor 1
Within d, the winding start end and winding end end of the electromagnetic coil 2 are taken out to the friction plate 4 side (the armature 8 side), and a positive lead 16 is connected to one of the both ends, and the other end is connected. Is connected to a lead wire 17 on the negative electrode side. In this embodiment, the two lead wires 16, 17 are used.
Are arranged at symmetrical positions approximately 180 ° apart in the clutch circumferential direction.

A slip ring holding member 18 is disposed on the inner peripheral side of the rotor 1 and the armature 8, and the holding member 18 is formed of an electrically insulating material such as resin and has a substantially ring-like shape extending in the rotor radial direction. It is molded into.
In this example, the diameter of the positive-electrode-side slip ring 19 is set smaller than the diameter of the negative-electrode-side slip ring 20, and the two slip rings 19, 20 are arranged concentrically and shifted by a predetermined amount in the axial direction. Both slip rings 1 in the arrangement state
9 and 20 are insert-molded on the inner peripheral portion of the holding member 18. Thereby, the two slip rings 19 and 20 on the positive electrode side and the negative electrode side are located on the inner peripheral side of the boss portion 6a and are integrally held by the holding member 18.

The outer peripheral portion of the above-mentioned slip ring holding member 18 is fitted and fixed (for example, adhesively fixed) to the inner wall surface of the inner peripheral cylindrical portion 1b of the rotor 1. Thereby, the slip ring holding member 18 can be integrated with the inner peripheral cylindrical portion 1b of the rotor 1, and the slip ring holding member 18 rotates integrally with the rotor 1. The two slip rings 19 and 20 are made of a conductive metal such as copper. In this example, the positive side slip ring 19 located on the inner peripheral side has a positive terminal piece and the negative side slip located on the outer peripheral side. Terminal pieces on the negative electrode side are integrally formed on the ring 20 by a method such as cutting or pressing. The positive-electrode-side slip ring 19 and the positive-electrode-side lead wire 16 are connected to each other by mechanically caulking the end of the positive-electrode-side lead wire 16 to the positive-electrode-side terminal piece of the positive-electrode-side slip ring 19 and then soldering. Mechanically and electrically coupled. The negative side slip ring 20 and the negative side lead wire 17 are mechanically and electrically coupled by the same means.

On the other hand, a cylindrical space 21 is formed between the central cylindrical portion 11b of the hub 11 fixed to the rotating shaft 13 of the compressor 5 and the inner peripheral surface of the boss portion 6a. The brushes 21, 23 on the positive electrode side and the negative electrode side, and a holding member 24 for the brushes 22, 23 are arranged on 21. The brush holding member 24 is formed of an electrically insulating material such as a resin into a substantially ring shape, and two brush storage recesses having an arc-shaped cross section are provided at symmetric positions approximately 180 ° apart in the circumferential direction of the brush holding member 24. 24a and 24b are formed.
The brush storage recesses 24a and 24b are formed in a shape having a sufficient axial dimension (depth) extending along the axial direction of the brush holding member 24 as shown in FIG.
The bottom of 4b is closed by a ring-shaped bottom 24c.

FIG. 1 is a sectional view taken along the line AOA of FIG. 2, so that the positive electrode side brush 22, the brush accommodating recess 24a and the like are not originally shown in FIG. This is illustrated by a virtual line (two-dot chain line). Brush 2
The positive and negative brushes 22 and 23 are formed in an arc-shaped cross section along the brush receiving recesses 24a and 24b. The positive brush 22 is axially slidably received in one of the brush receiving recesses 24a. And the bottom portion 2 of the brush receiving recess 24a
4c as an elastic pressing member.
Is arranged. Therefore, the other end of the positive brush 22 is always pressed against the positive slip ring 19 by the spring force of the coil spring 25.

The brush 23 on the negative electrode side is slidably housed in the other brush housing recess 24b in the axial direction, and is located between one end of the brush 23 on the negative electrode side and the bottom surface 24c of the brush housing recess 24b. A coil spring 26 is disposed as an elastic pressing member. Therefore, the other end of the brush 23 on the negative electrode side is always pressed against the slip ring 20 on the negative electrode side by the spring force of the coil spring 26.

The brush holding member 24 is positioned and held on the inner peripheral surface of the boss 6a in the rotational direction, and is fixedly fastened to the front housing 6 by means of screws or the like. Positive and negative lead wires (pigtail) are provided at one end of the positive brush 22 and the negative brush 23, respectively.
One end of each of the lead wires 27 and 28 is electrically connected to each other.
28 penetrates through the bottom surface portion 24c of the brush storage recesses 24a and 24b, and
And is electrically connected to an external control circuit (not shown) for interrupting the energization of the electromagnetic coil 2.

Next, a description will be given of the configuration of the air passage for discharging the abrasion powder of the brushes 22 and 23 to the outside of the clutch and the blowing means. As can be understood from the above configuration, a predetermined gap (for example, about 0.75 mm) is set between the two slip rings 19 and 20 on the positive electrode side and the negative electrode side. The presence of wear powder (conductive material) due to wear of the brushes 22, 23 may cause an electrical short circuit between the slip rings 19, 20 and abnormal wear of the brushes.

Therefore, in this embodiment, the following configuration is employed in order to smoothly discharge the brush abrasion powder. FIG. 2 shows the front housing 6 of the compressor 5 alone.
3 is a front view of the vicinity of the center of the slip ring holding member 18 as viewed from the direction of the arrow P in FIG. On the outer peripheral surface of the boss portion 6a of the front housing 6, a first air passage 30 having a concave groove shape extending in the axial direction is formed. This first air passage 3
Reference numeral 0 denotes a groove that is concave in an arc-shaped cross section from the outer peripheral surface of the boss 6a, as shown in FIG. 2, and is formed at three circumferential positions on the outer peripheral surface of the boss 6a. This first air passage 3
The groove shape of 0 can be easily formed at the same time when the front housing 6 is die-cast with aluminum. When the electromagnetic clutch is mounted on the front housing 6, the outer peripheral side of the first air passage 30 is located on the inner race 7 b of the bearing 7.
Is closed.

As shown in FIG. 1, the first air passage 30 extends in the axial direction to the distal end of the boss 6a on the outer side in the axial direction, so that one end of the first air passage 30 (the left end in FIG. 1). Part) communicates with the periphery of the sliding part between the slip rings 19, 20 and the brushes 22, 23. In the front housing 6, a surface extending radially outward at the root of the boss 6a includes:
An air inlet 31 is formed so as to communicate with the other end (the right end in FIG. 1) of the first air passage 30.

This air inlet 31 also has a concave groove shape.
The other end of the first air passage 30 is opened to the outside through the air inlet 31. In FIG. 1, arrows indicate the flow of air flowing from the air inlet 31 through the first air passage 30 and around the brush sliding portion. Further, a lead wire hole 32 penetrating between the inner and outer peripheries of the boss 6a is formed at the base of the boss 6a in the front housing 6, as shown in FIG. The lead hole 32 is for wiring the positive lead 27 of the positive brush 22. The lead 27 passes through the bottom surface 24 c of the brush holding member 24 and then passes through the inside of the lead hole 32. Wire to the outside,
The front housing 6 is taken out.

The opening of the lead wire hole 32 may be enlarged so that the lead wire hole 32 has the role of the air suction port 31. On the other hand, a second air passage 33 formed of a ring-shaped gap is formed between the inner peripheral portion of the slip ring holding member 18 (the inner peripheral portion of the inner slip ring 19) and the outer peripheral surface of the central cylindrical portion 11b of the hub 11. Has formed. This second
One end of the air passage 33 (the right end in FIG. 1) communicates with the periphery of the sliding portion between the slip rings 19 and 20 and the brushes 22 and 23. The other end (left end in FIG. 1) of the second air passage 33 is opened to the outside through a gap between the plate-like portion 11a of the hub 11, the slip ring holding member 18 and the armature 8. In FIG. 1, the arrows indicate the flow of air flowing through the second air passage 33 and flowing around the brush sliding portion.

In the slip ring holding member 18, a plurality of ventilation holes 34 are formed in a portion on the radially outward side of the first air passage 30 by a small amount in the circumferential direction. As shown in FIG. 3 (b), the slip ring holding member 18 penetrates in the axial direction. Ventilation port 34
In the present example, there are twelve openings in the circumferential direction at predetermined intervals, and a tapered surface 35 and a first air blower are provided on the rear side in the rotation direction R of the slip ring holding member 18 with respect to the ventilation holes 34. A fan 36 is arranged. Here, the tapered surface 35 is inside the slip ring holding member 18 (right side in FIG. 1).
By expanding the opening cross-sectional area of the ventilation port 34 from the outside to the outside (the left side in FIG. 1), the air flow passing through the ventilation port 34 as indicated by the arrow is smoothly guided.

The first blower fan 36 is integrally formed with the slip ring holding member 18 made of resin.
8 has an elongated protruding blade shape that protrudes inward from the inner side surface and extends in the radial direction. With such a configuration, when the slip ring holding member 18 rotates in the direction of arrow R in FIG. 3, the first blower fan 36 also rotates in the same direction. 3 (b) (the left side) is pressurized. As a result, the air at the front part in the rotation direction of the fan 36 flows into the ventilation port 34 having a low pressure as shown by the arrow, and can be smoothly discharged to the outside of the slip ring holding member 18 along the tapered surface 35.

On the outer surface side (left side surface in FIG. 1) of the slip ring holding member 18, the first blower fan 36
The second blower fan 37 is disposed at a position on the inner peripheral side of the second fan. The second blower fan 37 is also integrally formed with the slip ring holding member 18 made of resin, and projects outward from the outer surface of the slip ring holding member 18.
It has an elongated protruding blade shape that is inclined forward by a predetermined amount in the rotation direction R and extends in the radial direction. With such a configuration,
The second blower fan 37 can blow the surrounding air inward in the radial direction to send the air into the second air passage 33.

Next, the operation of the above configuration will be described.
Since the rotor 1 is rotatably supported on the outer peripheral surface of the boss 6a of the front housing 6 by the bearing 7,
When an automobile engine (not shown) is operated, the rotation of the crank pulley of the engine is transmitted to the pulley 1a via a belt (not shown), and the rotor 1 and the electromagnetic coil 2 constantly rotate.

As the rotor 1 and the electromagnetic coil 2 rotate, the lead wires 16 and 17 and the slip ring holding member 1
8, and the slip rings 19, 20 rotate together. On the other hand, the brushes 22 and 23 and the brush holding member 2
4. The coil springs 25 and 26 are all bosses 6a.
It is held on the side and fixed. Accordingly, one end faces in the axial direction of the brushes 22 and 23 are pressed against the rotating slip rings 19 and 20 by the spring force of the coil springs 25 and 26 and slide.

In order to operate the compressor 5 in the above state, the voltage of the vehicle-mounted power supply battery is applied to the lead wires (pigtails) 2 of the brushes 22 and 23 by an external control circuit (not shown).
When applied between 7 and 28, the members (16, 17,
19, 20, 22, 23, 27, and 28), a current flows through the electromagnetic coil 2 via the current path. Then
Since magnetic flux flows through a magnetic circuit formed between the rotor 1 and the friction plate 4 and the armature 8, an electromagnetic attraction force is generated between the friction surface 1e of the rotor 1 and the friction plate 4 and the armature 8. Thereby, the armature 8 is attracted and attracted to the friction surface 1e of the rotor 1 and the friction plate 4 against the axial elastic force of the plate spring 9 (force in the left direction in FIG. 1).

As a result, the rotor 1 and the armature 8 rotate integrally, and the armature 8 further rotates integrally with the hub 11 via the leaf spring 9 and the rivets 10. Therefore, the rotor 1 is connected to the rotating shaft 13 of the compressor 5 through the hub 11.
Is transmitted, and the compressor 5 operates. On the other hand, when the compressor 5 is stopped, the electromagnetic coil 2 is controlled by an external control circuit.
Cut off the power supply to. As a result, the electromagnetic attraction force disappears, so that the armature 8 is separated from the friction surface 1e of the rotor 1 and the friction plate 4 by the axial elastic force of the leaf spring 9, and the rotation transmission to the rotary shaft 13 of the compressor 5 is cut off. Therefore, the compressor 5 stops.

By the way, the slip ring holding member 18
Is always rotating together with the rotor 1, the electromagnetic coil 2 and the like during the operation of the engine as described above. The first blower fan 36 and the second blower fan 37 rotate integrally with the slip ring holding member 18, and the first blower fan 36 generates an airflow passing through the ventilation opening 34 as indicated by an arrow,
Reduce the pressure around the brush sliding part.

Therefore, external air is sucked from the air suction port 31 and passes through the first air passage 30 as shown by the arrow and flows around the brush sliding portion. At the same time, the air around the second blower fan 37 is blown inward in the radial direction by the rotation of the second blower fan 37, passes through the second air passage 33 as indicated by an arrow, and flows around the brush sliding portion. The air flowing around the brush sliding portion in this manner is then
The air passes through the ventilation hole 34 as shown by the arrow and is discharged to the outside of the slip ring holding member 18 (the left side in FIG. 1).

As described above, with the rotation of the slip ring holding member 18, an air flow constantly discharged to the outside around the brush sliding portion can be forcibly generated. It can be discharged well to the outside of the slip ring holding member 18 together with the air flow. As a result, slip rings 19, 20 due to brush wear powder
Can be reliably prevented from being short-circuited.

(Other Embodiments) The second blower fan 37 in the above embodiment is not always necessary.
May be abolished. In each of the above embodiments, the present invention is applied to a coil rotation type electromagnetic clutch in which the electromagnetic coil 2 is disposed on a driving rotor (driving rotating member) 1 integrated with the pulley portion 1a. However, as another type of coil rotating electromagnetic clutch, a compressor (rotating machine)
(The driven-side rotating member) 1 connected to the rotating shaft 13 of FIG.
In addition to disposing the electromagnetic coil 2 on one side, the armature 8
Is connected to the drive-side rotor 1 via a leaf spring (elastic connection member) 9, and the armature 8 is attracted to the hub 11 by the electromagnetic attraction of the electromagnetic coil 2, so that the rotation of the drive-side rotor 1 is A type that transmits power to the rotating shaft 13 via the hub 11 is also known, and the present invention can be applied to such a type of electromagnetic clutch.

In each of the above embodiments, the positions of the illustrated positive (+) and negative (−) members in the current path to the electromagnetic coil 2 may be replaced with the positive and negative electrodes. Absent. In addition, the specific configuration of the energization path to the electromagnetic coil 2 is not limited to the illustrated one, and it is needless to say that various modifications can be made according to the specifications of the electromagnetic clutch.

In the above-described embodiment, the groove shape of the first air passage 30 is a groove shape depressed in an arc-shaped cross section from the outer peripheral surface of the boss portion 6a. Needless to say, the shape may be a square shape, a V-shaped cross section, or the like.

[Brief description of the drawings]

FIG. 1 is a sectional view of an electromagnetic clutch according to an embodiment of the present invention, showing a section taken along line AOA of FIG. 2;

FIG. 2 is a front view of a central portion of the compressor front housing shown in FIG.

3A is a front view of a central portion of the slip ring holding member shown in FIG. 1, and FIG. 3B is a cross-sectional view taken along line ZZ of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotor (drive side rotating member) 2: Electromagnetic coil, 5 ...
Compressor (rotary machine), 6 front housing, 6a
Boss part, 7 bearing, 8 armature, 9 leaf spring (elastic connecting member) 11 hub (driven side rotating member), 13 rotary shaft, 18 slip ring holding member, 19, 20 slip ring, 22 , 23 ... brush, 24 ... brush holding member, 30 ... first air passage, 31 ... suction port, 33 ... second air passage, 34 ... ventilation hole, 36 ... first blowing fan, 37 ...
Second blower fan.

Claims (7)

[Claims] A rotary shaft (13) is arranged at the center of a cylindrical boss (6a) provided in a housing (6), and an electromagnetic clutch for interrupting transmission of rotation to the rotary shaft (13) is provided. A rotating machine (5), comprising: a rotating member (1); an electromagnetic coil (2) that is electrically insulated disposed on the rotating member (1) and generates an electromagnetic attraction force when energized; The rotating member (1) is disposed opposite to the rotating member (1) by electromagnetic attraction generated by the electromagnetic coil (2).
An armature (8) that is attracted to the electromagnetic coil (2); and a sliding energizing mechanism that energizes the electromagnetic coil (2). The sliding energizing mechanism includes a slip ring (19, 20).
And a brush (22, 23) for pressing against the slip ring (19, 20). The armature (8) is attracted to the rotating member (1), so that the rotating member (1) is ) And the armature (8) to transmit the rotation to the rotating shaft (13), and further, a first air passage (30) extending in the axial direction to the outer peripheral side of the boss (6a). And the first air passage (3)
One end of the first air passage (30) communicates with the periphery of a sliding portion between the slip rings (19, 20) and the brushes (22, 23), and the other end of the first air passage (30) is open to the outside. A first blowing means (3) rotating together with the rotating member (1);
6), and the first blowing means (36)
A rotary machine with an electromagnetic clutch, wherein air is suctioned from an air passage (30), and the suctioned air is discharged to the outside after passing around the sliding portion. 2. A portion on the inner peripheral side of the boss portion (6a),
The slip ring (19, 20) and the brush (2
The rotating machine with an electromagnetic clutch according to claim 1, wherein a sliding energizing mechanism including (2, 23) is arranged. 3. The rotating member (1) is rotatably supported on an outer peripheral surface of the boss (6a) via a bearing (7), and the first air passage (30) is provided on the boss. 3. The rotary machine with an electromagnetic clutch according to claim 1, wherein the rotary machine is formed in a groove shape extending in an axial direction on an outer peripheral surface of the portion (6a). 4. The slip ring (19, 20) is held by the rotating member (1) via a slip ring holding member (18), and the slip ring holding member (18) The air vent (34) for discharging air around the sliding part to the outside and the first air blowing means (36) are provided.
4. The rotary machine with an electromagnetic clutch according to any one of claims 1 to 3. 5. The rotating member according to claim 1, wherein the rotating member is a driving-side rotating member that rotates by receiving a driving force from a driving source, and a driven-side rotating member connected to the rotating shaft.
1), wherein the armature (8) is connected to the driven side rotating member (11) via an elastic connecting member (9), and an inner peripheral portion of the slip ring holding member (18) and the driven side rotating member. A second air passage (33) is formed between the second air passage (33) and the outer periphery of the sliding member, and external air flows around the sliding portion through the second air passage (33). Item 4
2. A rotary machine with an electromagnetic clutch according to claim 1. 6. The slip ring holding member (18) is provided with a second blowing means (37) for blowing external air toward the periphery of the sliding portion through the second air passage (33). The rotating machine with an electromagnetic clutch according to claim 5. 7. The slip ring holding member (18),
The rotating machine with an electromagnetic clutch according to claim 6, wherein the first blowing means (36) and the second blowing means (37) are integrally formed of resin.