JP7309265B2 - electromagnetic clutch - Google Patents

Description

The present invention relates to electromagnetic clutches.

For example, a gas compressor of an air conditioning system (hereinafter referred to as an air conditioning system) mounted on a vehicle or the like receives power from a power source (engine or the like) of the vehicle or the like to operate. In this case, an electromagnetic clutch is used to connect and disconnect power supply from the power source. An electromagnetic clutch has a rotor, an electromagnetic coil, and an armature. The rotor always rotates under the power of the power source, and the armature is connected to the rotating shaft of the gas compressor. The electromagnetic coils are arranged inside the space formed in the rotor.

The armature does not rotate because it is separated from the rotating rotor through a certain gap in the axial direction, but when the electromagnetic coil generates a magnetic force when energized, the magnetic force causes the armature to accommodate the electromagnetic coil. It is attracted to the rotor and axially displaced or deformed. As a result, the friction surface of the armature (perpendicular to the axial direction) and the friction surface of the rotor (perpendicular to the axial direction) come into contact with each other, and the friction force generated on both friction surfaces causes the armature to rotate integrally with the rotor. A rotating shaft connected to rotates. An elastic force such as a spring member acts on the armature, and when the electromagnetic coil is deenergized, the magnetic force that attracts the armature disappears, and the armature is returned to the state separated from the rotor by this elastic force.

In this way, the electromagnetic clutch is connected and disconnected with the power source depending on whether or not voltage is applied to the electromagnetic coil. be. It is said that this squealing noise is affected by arc-shaped slits formed in the rotor end plate on which the friction surface of the rotor is formed so as to penetrate in the axial direction and extend in the circumferential direction around the shaft. For this reason, proposals have been made to ensure the strength of the portion (bridge portion) where the slits are connected while devising the arrangement of the slits so as to prevent the generation of the squeal (see, for example, Patent Document 1). The arrangement of the slits includes, for example, one having eight bridges, one having six bridges, and one having four bridges.

JP-A-5-099245

Incidentally, according to research conducted by the inventor of the present application, it was found that the difference in rigidity in the direction of rotation of the rotor affects the generation of squeal noise. In particular, the arrangement of slits having eight bridges is likely to generate squealing noise, and even the arrangement of slits having six bridges may pose a problem of squealing noise.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnetic clutch capable of preventing or suppressing the generation of squealing noise and suppressing magnetic flux leakage while ensuring strength.

The present invention provides a rotor having an end plate in which an annular electromagnetic coil is accommodated and in which a slit row extending along the circumference around the center of the annular ring is formed; and an armature that is connected and disconnected to the end plate, wherein the slit row is arranged so that relatively long slits and short slits are aligned in at least a part along the circumference, and the slits The row is an electromagnetic clutch arranged so as not to overlap, at least in part, with the slit row when the end plate is rotated about the center by an angle of 45 degrees.

According to the electromagnetic clutch of the present invention, it is possible to prevent or suppress the generation of squealing noise, and to suppress magnetic flux leakage while ensuring strength.

1 is a cross-sectional view of a main part showing a compressor having an electromagnetic clutch according to one embodiment of the invention; FIG. FIG. 2 is a view of the end plate of the rotor of the compressor shown in FIG. 1 viewed axially from the armature side; FIG. 3 is a view corresponding to FIG. 2 showing a state in which the end plate shown in FIG. 2 is rotated by an angle of 45[°] around the axis. FIG. 3 is a side view corresponding to FIG. 2, showing a modified end plate in which a slit row is formed in which long slits are arranged at angular intervals of 120[°] around the axis; Fig. 10 shows a modified end plate in which the radially outer row of slits is arranged to alternate between long and short slits, and the radially inner row of slits is arranged to consist only of slits of constant length; FIG. 3 is a side view corresponding to FIG. 2; FIG. 10 is a diagram showing an end plate in which long slits are arranged side by side in a part of the circumferential direction, and shows a configuration in which each of the outer slit row and the inner slit row has five slits. FIG. 10 is a diagram showing an end plate in which long slits are arranged side by side in a part of the circumferential direction, and shows a configuration in which each of the outer slit row and the inner slit row has six slits. FIG. 10 is a diagram showing an end plate in which long slits are arranged side by side in a part of the circumferential direction, and shows a configuration in which each of the outer slit row and the inner slit row has seven slits. FIG. 10 is a diagram showing an end plate in which long slits are arranged side by side in a part of the circumferential direction, and shows a configuration in which the outer slit row and the inner slit row each have nine slits. FIG. 10 is a diagram showing an end plate in which long slits are arranged side by side in a part of the circumferential direction, and shows a configuration in which each of the outer slit row and the inner slit row has ten slits. An example of an end plate in which the outer slit row is formed with all slits of equal length along the circumference and the inner slit row is formed with long slits and short slits is shown. The long slits and short slits in the outer slit row and the long slits and short slits in the inner slit row are formed in different phase ranges, and the ratio of the length of the long slits to the length of the short slits in the outer slit row is a diagram showing an example of the end plate 92A formed at a ratio larger than the ratio of the length of the long slit 92d to the length of the short slit in the inner slit row. The long slits and short slits in the outer slit row and the long slits and short slits in the inner slit row are formed in different phase ranges, and the ratio of the length of the long slits to the length of the short slits in the outer slit row is a diagram showing an example of an end plate 92A formed with a smaller ratio than the ratio of the length of a long slit 92d to the length of a short slit in the inner slit row. FIG. 4 is a diagram showing an example of an end plate in which slit rows are formed on three concentric circles with different radii from the center.

An embodiment of an electromagnetic clutch according to the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of essential parts showing a compressor 100 having an electromagnetic clutch 90 according to one embodiment of the present invention. The illustrated compressor 100 is, for example, a vane rotary type gas compressor.

<Compressor>
A compressor 100 shown in FIG. 1 is mounted on a vehicle and configured as part of an air conditioning system (hereinafter simply referred to as an air conditioning system) that performs cooling using heat of vaporization of a cooling medium. It is provided on the circulation path of the cooling medium together with the condenser, expansion valve, evaporator, etc., which are the components of .

The compressor 100 compresses a refrigerant gas G (gas) as a gaseous cooling medium taken from the evaporator of the air conditioning system and supplies the compressed refrigerant gas to the condenser of the air conditioning system. The condenser heat-exchanges the compressed refrigerant gas with the surrounding air or the like to cause the refrigerant gas to radiate heat, liquefy it, and send it to the expansion valve as a high-pressure liquid refrigerant. The high-pressure liquid refrigerant is pressure-reduced by the expansion valve and sent to the evaporator. The low-pressure liquid refrigerant absorbs heat from the surrounding air and evaporates in the evaporator, and heat exchange accompanying the vaporization of this refrigerant cools the air around the evaporator. The vaporized low-pressure refrigerant gas G is returned to the compressor 100 and compressed, and the above steps are repeated.

The compressor 100 includes a compression mechanism portion 60 that takes in a low-pressure refrigerant gas G, compresses it to a high pressure and discharges it, a housing 10 that accommodates the compression mechanism portion 60 therein, and a housing 10 for driving the compression mechanism portion 60. and an electromagnetic clutch 90 for connecting and disconnecting power supply from an external power source.

The housing 10 comprises a case 11 closed at one end and a front head 12 covering the open end of the case 11 . With the front head 12 covering the end of the case 11 , a space for accommodating the compression mechanism 60 is formed inside the housing 10 . The compression mechanism 60 has a rotating shaft 51 lubricated with refrigerating machine oil R. As this rotating shaft 51 rotates, the low-pressure refrigerant gas G is sucked into the interior, compressed to a high pressure, and discharged to the outside. do.

Here, one end 51a of the rotating shaft 51 is exposed to the outside of the housing 10 . Specifically, the left end 51a of the rotating shaft is exposed to the outside of the front head 12 in the state shown in FIG.

<Electromagnetic Clutch>
The electromagnetic clutch 90 includes a pulley 91 , a rotor 92 , an electromagnetic coil 93 and an armature 94 . A belt is wound around an outer peripheral surface 91a of the pulley 91, in which a plurality of V-shaped grooves are formed along the circumferential direction. The belt receives power from the vehicle engine (an example of a power source) in which the compressor 100 is mounted. The rotor 92 is integrated with the pulley 91 . Therefore, when the pulley 91 receives power from an engine or the like, the pulley 91 and the rotor 92 rotate about the axis O together.

The electromagnetic coil 93 is fixed to the front head 12 via a yoke, does not rotate around the axis O, generates magnetic force when energized, and disappears when energized. The armature 94 has a hub 94b, an outer ring 94a and a leaf spring 94c. The hub 94b is fastened by a screw 70 to the end portion 51a of the rotary shaft 51 exposed from the front head 12. As shown in FIG.

The outer ring 94a is arranged to protrude radially outward from the hub 94b. The leaf spring 94c connects the hub 94b and the outer ring 94a so that the outer ring 94a can be displaced with respect to the hub 94b by elastic deformation of the leaf spring 94c along the direction in which the axis O extends. It has become.

The outer ring 94a is arranged with a slight gap between the end plate 92A of the rotor 92, and when the electromagnetic coil 93 is energized and the electromagnetic coil 93 generates a magnetic force, the magnetic force attracts the outer ring 94a. It is displaced against the elastic force of the leaf spring 94c to a position where it contacts the end plate 92A in the axial center O direction. As a result, the outer ring 94a of the armature 94 comes into contact with the end plate 92A of the rotor 92, and the frictional force causes the armature 94 to rotate together with the rotating rotor 92. Rotate.

On the other hand, when the electromagnetic coil 93 is de-energized, the magnetic force generated by the electromagnetic coil 93 disappears, and the outer ring 94a contacting the end plate 92A of the rotor 92 moves toward the end plate 92A due to the elastic force of the plate spring 94c. away from and returned to its original position. As a result, the armature 94 stops, and the compression mechanism section 60 of the compressor 100 also stops. Thus, the armature 94 is connected and disconnected to the end plate 92A according to the magnetic force generated by the electromagnetic coil 93. As shown in FIG.

The rotor 92 is fixed to the front head 12 via a radial bearing and is rotatable around the rotational axis O. The rotor 92 is formed with an annular coil accommodating space 92B in which an annular electromagnetic coil 93 centered on the axis O is accommodated. The rotor 92 has an end plate 92A formed with a friction surface with which the armature 94 comes into contact at the axial end nearer to the armature 94, which will be described later. This end plate 92A is formed in a range including a range corresponding to the coil housing space 92B in the radial direction around the axis O. As shown in FIG.

FIG. 2 is a view of the end plate 92A of the rotor 92 of the compressor 100 shown in FIG. 1 viewed from the armature 94 side in the direction of the axis O. FIG. 3 is a view corresponding to FIG. 2 showing a state in which the end plate 92A shown in FIG. 2 is rotated about the axis O by an angle of 45[°]. As shown in FIG. 2, the end plate 92A of the rotor 92 has an outer slit row SL1 extending along the circumference of radius r1 from the axis O and a slit row SL1 extending along the circumference of radius r2 (<r1). A slit row SL2 on the inner side is formed.

Here, the slit row SL1 is composed of eight slits 92a, 92b, 92a, 92b, 92a, 92b that pass through the end plate 92A in the direction of the axis O and are arranged on a circle with a radius r1 centered on the axis O. , 92a and 92b. The slit 92a is arc-shaped over an angle θ1 (45[°]<θ1<90[°]) around the axis O, and the slit 92b is an angle θ2 (0[°]<θ2<45[°]) around the axis O. ) are formed in an arc shape.

That is, the slit 92a is a slit relatively long in the circumferential direction with respect to the slit 92b, and the slit 92b is a slit relatively short in the circumferential direction with respect to the slit 92a. The relatively short slit 92b is formed to have a circumferential length of one-third or less of the relatively long slit 92a. The relatively long slits 92a and the relatively short slits 92b are alternately arranged along the entire circumferential direction. Between the relatively long slit 92a and the relatively short slit 92b, a bridge 92c that does not penetrate in the axial center O direction is formed.

The four relatively long slits 92a forming the slit row SL1 have the same length along the circumferential direction. Similarly, the four relatively short slits 92b forming the slit row SL1 have the same circumferential length, and the eight bridges 92c have the same circumferential length. is.

Therefore, the four relatively long slits 92a are rotationally symmetrical at multiples of an angle of 90[°] around the axis O (when rotated by an angle of 90[°] around the axis O, they are the same as before rotation). It's becoming Similarly, the four relatively short slits 92b and the eight bridges 92c are also rotationally symmetrical at multiples of the angle 90[°] around the axis O, respectively. Therefore, the slit row SL1 as a whole is rotationally symmetric about the axis O at multiples of an angle of 90[°].

The slit row SL2 also has eight slits 92d, 92e, 92d, 92e, 92d, 92e, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92d, 92e. The slit 92d is arc-shaped over an angle θ1 (45[°]<θ1<90[°]) around the axis O, and the slit 92e is an angle θ2 (0[°]<θ2<45[°]) around the axis O. ) are formed in an arc shape.

That is, the slit 92d is a slit relatively long in the circumferential direction with respect to the slit 92e, and the slit 92e is a slit relatively short in the circumferential direction with respect to the slit 92d. The relatively long slits 92d and the relatively short slits 92e are alternately arranged in the circumferential direction. Between the relatively long slit 92d and the relatively short slit 92e, a bridge 92f that does not penetrate in the axial center O direction is formed.

The four relatively long slits 92d forming the slit row SL2 have the same length along the circumferential direction. Similarly, the four relatively short slits 92e forming the slit row SL2 also have the same circumferential length, and the eight bridges 92f also have the same circumferential length. is.

Therefore, the four relatively long slits 92d, the four relatively short slits 92e, and the eight bridges 92f are rotationally symmetrical about the axis O at multiples of 90[°]. Therefore, the slit row SL2 as a whole has rotational symmetry around the axis O at multiples of an angle of 90[°].

The long slits 92a of the slit row SL1 and the long slits 92d of the slit row SL2 are formed in the same phase range around the axis O. Similarly, the short slits 92b of the slit row SL1 and the short slits 92e of the slit row SL2 are formed in the same phase range around the axis O, and the bridge 92c of the slit row SL1 and the bridge 92f of the slit row SL2 are formed in the same phase range. They are formed in the same phase range around the center O.

As a result, the ratio L1b/L1a between the length L1a along the circumference of the long slit 92a in the slit row SL1 and the length L1b along the circumference of the short slit 92b and the circumference of the long slit 92d in the slit row SL2 The ratio L2e/L2d between the length L2d along the length L2d and the length L2e along the circumference of the short slit 92e is a substantially equal ratio (L1b/L1a≈L2e/L2d).

As described above, in the electromagnetic clutch 90 of the present embodiment, the slit row SL1 is rotationally symmetrical at multiples of the angle 90[°] around the axis O, but the angle 45[°] around the axis O is rotationally symmetrical. (or 135[°]) is not rotationally symmetrical. That is, the end plate 92A shown in FIG. 2 and the end plate 92A shown in FIG. 3 obtained by rotating the end plate 92A shown in FIG. , the slit rows SL1 do not overlap at least partially.

That is, the slits 92a of the slit row SL1 before being rotated by an angle of 45[°] do not completely overlap the slits 92a of the slit row SL1 after being rotated by an angle of 45[°]. The slits 92b of the slit row SL1 before the angle 45[°] do not completely overlap with the slits 92b of the slit row SL1 after the angle 45[°].

Therefore, the electromagnetic clutch 90 of the present embodiment has a direction of an angle of 45[°] and an angle of 135[°] around the axis O, and a direction of an angle of 0[°] around the axis O and an angle of 90[°]. ], the strength is different due to the difference in rigidity.

Here, when connecting/disconnecting the electromagnetic clutch 90 (when connecting/disconnecting the armature 94 and the rotor 92), the rigidity (strength) in the direction of the angle 45[°] around the axis O and the direction of the angle 135[°] , The difference in rigidity (strength) in the direction of the angle 0 [°] and the direction of the angle 90 [°] around the axis O has an effect on the so-called squealing noise. bottom.

The electromagnetic clutch 90 of this embodiment has a direction of an angle of 45[°] and an angle of 135[°] around the axis O, and a direction of an angle of 0[°] and an angle of 90[°] around the axis O. Since the rigidity differs depending on the direction, it is possible to prevent or suppress the generation of squealing noise when the electromagnetic clutch 90 is connected or disconnected.

Further, in the electromagnetic clutch 90 of the present embodiment, the slit row SL1 has a long slit 92a and a short slit 92b arranged side by side in at least a part of the circumferential direction in which the slit row SL1 extends. It can be formed in a bridge 92c between long slits 92a, 92a. Thereby, it is possible to prevent or suppress an increase in the circumferential length of the bridge 92c between the two long slits 92a, 92a.

If the length of the bridge between the two long slits 92a, 92a in the circumferential direction increases, the amount of magnetic flux generated by the electromagnetic coil 93 that leaks from the bridge increases, which may reduce the attractive force. However, the electromagnetic clutch 90 of this embodiment has a structure in which two short bridges 92c are formed on both sides of the short slit 92b due to the configuration in which the short slit 92b is formed in the long bridge. Therefore, since the two short bridges 92c are shorter in length than one long bridge without the short slits 92b, the electromagnetic clutch 90 of the present embodiment prevents magnetic flux from leaking through the bridges. can be reduced to prevent or suppress a decrease in the suction force.

Note that the two bridges 92c formed on both sides of the short slit 92b have a short distance therebetween (corresponding to the length of the short slit 92b), so they are stronger than those with a long distance. Therefore, the pair of two bridges 92c functions in the entire slit row SL1 in the same manner as one long bridge formed between the long slits 92a, and can ensure the strength of the end plate 92A.

Further, in the electromagnetic clutch 90 of the present embodiment, the slit row SL1 has long slits 92a and short slits 92b alternately arranged over the entire circumferential direction, and the long slits 92a are arranged adjacent to each other. Since the short slits 92b are not arranged adjacent to each other, the end plate 92A does not have a portion with different strength in the circumferential direction. Note that the electromagnetic clutch according to the present invention is not limited to one in which the long slits 92a and the short slits 92b are alternately arranged over the entire circumferential direction. Therefore, in a part of the slit row SL1 in the circumferential direction, the long slits 92a may be arranged adjacent to each other, or the short slits 92b may be arranged adjacent to each other.

6, 7, 8, 9, 10, and 11 are diagrams showing an end plate 92A in which long slits 92a are arranged side by side in a part of the circumferential direction. Here, FIG. 6 shows an end plate 92A in which the outer slit row SL1 and the inner slit row SL2 each have five slits 92a, 92a, 92a, 92a, 92b and slits 92d, 92d, 92d, 92d, 92e. There is. It should be noted that the end plates 92A shown in FIGS. 6, 7, 8, 9, 10 and 11 are not included in the embodiments of the present invention.

Similarly, FIG. 7 shows a configuration in which the outer slit row SL1 and the inner slit row SL2 each have six slits 92a, 92a, 92b, 92a, 92a, 92b and slits 92d, 92d, 92e, 92d, 92d, 92e. It is the end plate 92A.

Similarly, FIG. 8 shows that the outer slit row SL1 and the inner slit row SL2 each have seven slits 92a, 92a, 92b, 92a, 92b, 92a, 92b and slits 92d, 92d, 92e, 92d, 92e, 92d, 92e. is an end plate 92A having a configuration.

Similarly, FIG. 9 shows that the outer slit row SL1 and the inner slit row SL2 are composed of nine slits 92a, 92a, 92b, 92b, 92a, 92b, 92a, 92b, 92b and slits 92d, 92d, 92e, 92e, 92d. , 92e, 92d, 92e, 92e.

Similarly, FIG. 10 shows that the outer slit row SL1 and the inner slit row SL2 each include ten slits 92a, 92b, 92a, 92b, 92b, 92a, 92b, 92a, 92b, 92b, slits 92d, 92e, 92d, End plate 92A in the form of having 92e, 92e, 92d, 92e, 92d, 92e, 92e.

The end plate 92A of the embodiment shown in FIGS. 6-10 has long slits 92a aligned in a part of the circumferential direction. The slits 92a (or the long slits 92e) and the short slits 92b (or the short slits 92e) are arranged partially in the circumferential direction, but are not arranged alternately over the entire circumference.

In the end plate 92A configured in this manner, virtual eight dividing lines L are assumed to divide the end plate 92A into eight equiangularly spaced regions with an angle of 45[°] around the center O. When the parting line L of is integrally rotated around the center O by an angle of 45[°], at least one of the rotation angle positions during the rotation of the angle of 45[°] is formed between two adjacent slits. Equiangularly spaced areas including the center of the bridge 92c (or bridge 92f) and equiangularly spaced areas not including the bridge 92c (or bridge 92f) are alternately arranged along the circumferential direction around the center O, At least one of the equiangularly spaced regions including the centers of the bridges 92c (or bridges 92f) includes the centers of two or more bridges 92c (92f).

In the end plate 92A configured in this way, the slit row SL1 (or slit row SL2) is composed of long slits 92a (or long slits 92e) and short slits 92b (or short slits 92e) along the entire circumference. Although not arranged alternately, two adjacent equiangularly spaced regions (two equiangularly spaced regions having a direction difference of 45 [degrees]) have bridges 92c (or bridges 92f)). Therefore, the area has a relatively high rigidity and the area has a relatively low rigidity because it does not have the bridge 92c (or the bridge 92f).

Therefore, a difference in rigidity is formed by a difference in direction of an angle of 45 [degrees] around the center O, and it is possible to prevent or suppress the generation of a squeal sound when the electromagnetic clutch 90 is connected or disconnected. In particular, the difference in rigidity is increased between the equiangularly spaced region in which two or more bridges 92c (or bridges 92f) are formed and the equiangularly spaced region in which no bridges 92c (or bridges 92f) are formed. be able to.

6-10, the long slits 92a of the outer slit row SL1 and the long slits 92d of the inner slit row SL2 are arranged in the same phase range around the center O. The short slits 92b of the slit row SL1 on the outer side and the short slits 92e of the slit row SL2 on the inner side are formed in the same phase range around the center O.

In addition, among the electromagnetic clutches 90 of the above-described embodiment, if the short slits 92b of the slit row SL1 are one-third or less of the circumferential length of the long slits 92a, the difference in rigidity can be sufficiently increased. can. In addition, the electromagnetic clutch according to the present invention is not limited to one in which the short slit 92b is one-third or less of the circumferential length of the long slit 92a. The angle θ1 of the relatively long slits 92a in the slit row SL1 (SL2) around the axis O is 360[°]/2n, where n is the number of relatively long slits in the slit row SL1. and less than 360[°]/n.

Further, among the electromagnetic clutches 90 of the above-described embodiment, in the one in which the long slits 92a of the slit row SL1 are arranged at angular intervals of 90 [°] around the axis O, the number of bridges 92c is reduced to eight. be able to.

The electromagnetic clutch according to the present invention is not limited to one in which the long slits 92a are arranged at angular intervals of 90[°] around the axis O. Therefore, for example, as shown in FIG. 4, the long slits 92a of the slit row SL1 may be arranged at angular intervals of 120[°] around the axis O, or as shown in FIG. They may be arranged at intervals of less than 90[°].

Further, in the electromagnetic clutch 90 of the present embodiment, the slit rows SL1 and SL2 are formed on two concentric circles having different radii around the axis O, respectively. It is sufficient if only one slit row is formed, and at least one slit row thus formed is configured like the slit row SL1 shown in the embodiment.

Therefore, for example, as shown in FIG. 5, only slits 92g having a constant length may be arranged side by side in the radially inner slit row SL2. In this case, it is preferable that the radially outer slit row SL1 has a part of the long slits 92a and the short slits 92b arranged side by side.

In the electromagnetic clutch 90 of the present embodiment, the long slits 92a in the slit row SL1 formed in the end plate 92A and the long slits 92d in the slit row SL2 are formed in the same phase range around the axis O, and Since the short slits 92b in the slit row SL1 and the short slits 92e in the slit row SL2 are formed in the same phase range around the axis O, the oblique directions (45 [°] direction and 135 [°] direction) A greater difference can be given between the rigidity and the rigidity in the vertical and horizontal directions (90[°] direction and 0[°] direction).

In the electromagnetic clutch 90 of the embodiment shown in FIGS. 4 and 5, the inner slit row SL2 is formed such that all the slits 92g have the same length along the circumference, and the outer slit row SL1 is formed with long slits 92a. Although formed with short slits 92b, the electromagnetic clutch according to the present invention may have a form opposite to this embodiment.

FIG. 11 shows an end plate 92A in which the outer slit row SL1 is formed with all the slits 92a having the same length along the circumference, and the inner slit row SL2 is formed with long slits 92d and short slits 92e. It is a figure which shows the example of.

An electromagnetic clutch 90 according to another embodiment of the present invention has an end plate 92A, as shown in FIG. , the inner slit row SL2 may be formed of a long slit 92d and a short slit 92e. The end plate 92A of the embodiment configured in this way can also exhibit the same effect as the electromagnetic clutch 90 of the embodiment described above.

In the electromagnetic clutch 90 of the embodiment shown in FIGS. 2 and 3, the long slits 92a in the outer slit row SL1 and the long slits 92d in the inner slit row SL2 are formed in the same phase range around the center O, and , the short slits 92b in the outer slit row SL1 and the short slits 92e in the inner slit row SL2 are formed in the same phase range around the center O. The long slit 92a and short slit 92b in the slit row SL1 and the long slit 92d and short slit 92e in the inner slit row SL2 may not be formed in the same phase range.

That is, the ratio L1b/L1a between the length L1a along the circumference of the long slit 92a in the outer slit row SL1 and the length L1b along the circumference of the short slit 92b, and the long slit 92d in the inner slit row SL2 The ratio L2e/L2d between the length L2d along the circumference of the short slit 92e and the length L2e along the circumference of the short slit 92e may be different from each other.

12 and 13 show an example of an end plate 92A in which the long slits 92a and short slits 92b in the outer slit row SL1 and the long slits 92d and short slits 92e in the inner slit row SL2 are formed in mutually different phase ranges. It is a figure which shows.

Specifically, the end plate 92A shown in FIG. 12 has a ratio L1b between the length L1a along the circumference of the long slit 92a and the length L1b along the circumference of the short slit 92b in the outer slit row SL1. /L1a is formed at a ratio greater than the ratio L2e/L2d between the length L2d along the circumference of the long slit 92d and the length L2e along the circumference of the short slit 92e in the inner slit row SL2. there is

On the other hand, in the end plate 92A shown in FIG. 13, the ratio L1b/L1a between the length L1a along the circumference of the long slit 92a and the length L1b along the circumference of the short slit 92b in the outer slit row SL1 is , the ratio L2e/L2d between the length L2d along the circumference of the long slit 92d and the length L2e along the circumference of the short slit 92e in the inner slit row SL2.

As shown in FIGS. 12 and 13, the electromagnetic clutch of another embodiment according to the present invention has a length L1a along the circumference of the long slit 92a and a length L1a along the circumference of the short slit 92b in the outer slit row SL1. and a ratio L2e/L2d between the length L2d along the circumference of the long slit 92d and the length L2e along the circumference of the short slit 92e in the inner slit row SL2. are formed at different ratios, the same effect as the electromagnetic clutch 90 of the above-described embodiment can be exhibited.

Further, according to the end plate 92A of the embodiment shown in FIGS. 12 and 13, the slit row SL1 or the slit row SL2 of the bridges 92c and 92f with the weaker strength (the one with the larger stress) has the shorter slits 92b and 92e. By increasing the ratio of the length of the long slits 92a and 92d to the length of the slits 92a and 92d, it is possible to balance the difference in rigidity between the directions of 45[°] and the strength of the bridges 92c and 92f.

Specifically, the slits in one of the outer slit row SL1 and the inner slit row SL2 are set to have a constant length (there is no difference in length), and the slit row SL1 on the outer side and the slit row SL2 on the inner side are The slits of both slit rows of the slit row SL2 are composed of a combination of long slits 92a, 92d and short slits 92b, 92e, respectively, and the ratio L1b of the lengths of the long slits 92a and the short slits 92b of the outer slit row SL1 /L1a and the length ratio L2e/L2d of the long slit 92d and the short slit 92e of the inner slit row SL2 are different, the difference in rigidity is larger.

Further, the slits of both the outer slit line SL1 and the inner slit line SL2 are formed by combining long slits 92a and 92d and short slits 92b and 92e, respectively, and the long slits 92a of the outer slit line SL1 and the short slits 92a and 92d are combined. The slits in the outer slit row SL1 are longer than those in which the length ratio L1b/L1a with respect to the slits 92b and the length ratio L2e/L2d between the long slits 92d and the short slits 92e in the inner slit row SL2 are different. 92a and the short slit 92b, and the length ratio L2e/L2d of the long slit 92d and the short slit 92e of the inner slit row SL2 are formed to be the same. difference is large.

On the other hand, the length ratio L1b/L1a between the long slits 92a and the short slits 92b in the outer slit row SL1 and the length ratio L2e/L2d between the long slits 92d and the short slits 92e in the inner slit row SL2 are The slits of both the outer slit row SL1 and the inner slit row SL2 are formed by combining long slits 92a and 92d and short slits 92b and 92e, respectively, so that the outer slit row The length ratio L1b/L1a between the long slits 92a and the short slits 92b of SL1 is different from the length ratio L2e/L2d between the long slits 92d and the short slits 92e of the inner slit row SL2. is high.

Further, the slits of both the outer slit line SL1 and the inner slit line SL2 are formed by combining long slits 92a and 92d and short slits 92b and 92e, respectively, and the long slits 92a of the outer slit line SL1 and the short slits 92a and 92d are combined. The length ratio L1b/L1a of the slit 92b and the length ratio L2e/L2d of the long slit 92d and the short slit 92e of the inner slit row SL2 are different from each other. The strength is higher when the slits in one of the slit rows SL2 have a constant length (there is no length difference).

The stress at the bridge 92f of the inner slit row SL2 and the stress at the bridge 92c of the outer slit row SL1 depend on the position of the center of the width direction of the belt wound around the pulley 91 in the direction of the axis O. different. That is, when the center position of the belt becomes farther from the friction surface of the end plate 92A with the armature 94, the stress in the bridge 92f of the inner slit row SL2 increases, and the center position of the belt moves away from the end plate 92A. As it approaches the friction surface with the armature 94, the stress in the bridge 92c of the outer slit row SL1 increases.

By increasing the length ratio of the bridges 92c and 92f on the side where the stress is large, the strength can be improved (increased).

FIG. 14 is a diagram showing an example of an end plate 92A in which slit rows SL1, SL2 and SL3 are formed on three concentric circles with different radii from the axis O (center).

In the electromagnetic clutch according to the present invention, as shown in FIG. 14, an end plate 92A has slit rows SL1, SL2, and SL3 formed on three concentric circles having different radii from an axis (center) O, respectively. At least one of the three slit rows SL1, SL2, and SL3 may be configured like the slit row SL1 shown in the above embodiment.

The end plate 92A shown in FIG. 14 has, for example, a third slit row SL3 formed inside the inner slit row SL2 in the end plate 92A shown in FIG. is formed of a long slit 92h and a short slit 92i, and a bridge 92j is formed between the slits 92h and 92i.

The third slit row SL3 may be formed further outside the outer slit row SL1 in the end plate 92A shown in FIG. and the inner slit row SL2. Also, the number of slit rows may be four or more.

The electromagnetic clutch 90 of each embodiment described above is for the compressor 100 which is an example of a gas compressor, but the electromagnetic clutch according to the present invention is not limited to the one for gas compressors. Further, the compressor 100 to which the electromagnetic clutch 90 of the present embodiment is applied is a vane rotary type gas compressor, but the electromagnetic clutch according to the present invention is used in a type gas compressor other than the vane rotary type. may be Therefore, the electromagnetic clutch according to the present invention can also be applied to an electromagnetic clutch used in a swash plate type gas compressor other than the vane rotary type, a scroll type gas compressor, and the like.

90 electromagnetic clutch 92 rotor 92A end plate 92a long slit 92b short slit 92c bridge 93 electromagnetic coil 94 armature 94a outer ring 100 compressor O axis SL1, SL2 slit row

Claims (10)

a rotor having an end plate formed with one or more slit rows extending along the circumference around the center of the ring and containing an annular electromagnetic coil;
an armature that connects and disconnects with the end plate according to the magnetic force of the electromagnetic coil,
The at least one slit row is arranged so that relatively long slits and short slits are aligned in at least a portion along the circumference , and the plurality of long slits have a length along the circumference direction. are the same, the plurality of short slits have the same length along the circumferential direction, and the slit rows are rotationally symmetrical about the center at multiples of an angle of 90[°] about the end plate. , and the electromagnetic clutch is arranged so as not to overlap at least a part of the slit array in a state rotated by an angle of 45[°]. Assuming a virtual dividing line that divides the end plate into equiangularly spaced areas with an angle of 45 [°] around the center, and rotating the dividing line by an angle of 45 [°] around the center, the angle At least one of the rotation angle positions during 45 [°] rotation,
In the slit row in which the long slit and the short slit are arranged so as to be aligned at least in part, the equiangular interval region including the center of the bridge formed between two adjacent slits and the above etc. not included Angularly spaced regions are alternately arranged along the circumferential direction around the center, and at least one of the equiangularly spaced regions containing the centers of the bridges contains the centers of two or more of the bridges. 2. The electromagnetic clutch according to 1. 3. The electromagnetic clutch according to claim 1, wherein said slit array includes said long slits and said short slits alternately arranged along the entire circumference. The electromagnetic clutch according to any one of claims 1 to 3, wherein the length of the short slit along the circumference is one-third or less of the length of the long slit along the circumference. . 5. The electromagnetic clutch according to any one of claims 1 to 4, wherein said long slit is formed with an angle around said center smaller than 90[°]. 5. The electromagnetic clutch according to claim 1, wherein said long slit has an angular interval of 90[°] around said center. Slit rows are respectively formed on two or more concentric circles having different radii from the center, and among the two or more slit rows, at least two slit rows are the long at least part of the circumference 7. The electromagnetic clutch according to any one of claims 1 to 6, wherein the slit and the short slit are arranged side by side. The ratio of the length of the long slit along the circumference and the length of the short slit along the circumference in the two slit rows outside the concentric circles, and the long slit rows in the two concentric circles inside the slit row 8. The electromagnetic clutch according to claim 7, wherein ratios of the length of the slit along the circumference and the length of the short slit along the circumference are different from each other. 9. The electromagnetic clutch according to claim 7, wherein the long slit and the short slit in the two concentric slit rows are formed in the same phase range around the center. 10. The electromagnetic clutch according to any one of claims 1 to 9, wherein the electromagnetic clutch connects and disconnects power supply from a power source of the vehicle to a gas compressor mounted on the vehicle.