JP5879972B2 - Electromagnetic clutch coupling - Google Patents

Description

  The present invention relates to a coupling that transmits driving force to a rotating shaft and absorbs torque fluctuation, and is provided, for example, in an electromagnetic clutch of a vehicle cabin air conditioner of a vehicle.

  2. Description of the Related Art Conventionally, in a vehicle cabin air conditioner for a vehicle, an electromagnetic clutch as shown in FIG.

  That is, the electromagnetic clutch 100 shown in FIG. 8 includes a non-rotating excitation coil 102, a rotor 104 disposed so as to surround the excitation coil 102, and rotatably held in the housing 101 via the bearing 103, An armature (clutch disc) 105 facing the end surface 104 a of the rotor 104 and a coupling 110 that connects the armature 105 to a rotating shaft 106 inserted through the housing 101 so as to be axially movable are provided.

  The coupling 110 includes a hub 111 fixed to the tip of the rotating shaft 106, and an outer ring 112 concentrically disposed on the outer peripheral side of the hub 111 and connected to the armature 105 via a plurality of circumferential rivets 107. And an annular elastic body 113 made of an elastic material having rubber-like elasticity that is vulcanized and bonded between the outer ring 112 and the rim portion 111a of the hub 111.

  In the electromagnetic clutch coupling 110 having the above-described configuration, the armature 105 magnetized by energizing the exciting coil 102 moves in the axial direction by a magnetic attractive force and is attracted (clutch meet) to the end face 104a of the rotating rotor 104. This is allowed by the axial shear deformation of the elastic body 113 and transmits the torque from the armature 105 to the rotating shaft 106. When the energizing coil 102 is not energized, the armature 105 is separated from the end face 104a of the rotor 104 in the axial direction with a gap G by the restoring force of the elastic body 113 (see, for example, Patent Document 1 below).

  However, in this type of electromagnetic clutch coupling 110, the magnetic attractive force acting between the rotor 104 and the armature 105 by energizing the exciting coil 102 is a process in which the armature 105 moves toward the end face 104 a of the rotor 104. In contrast to the non-linear increase, the axial shear spring force of the elastic body 113 acting as a resistance against the movement of the armature 105 toward the rotor 104 also increases with the movement of the armature 105, but the increase is almost linear. For this reason, immediately before the armature 105 is attracted to the rotor 104, the difference between the magnetic attractive force and the axial shear spring force of the elastic body 113 increases rapidly, and the movement of the armature 105 is accelerated. There is a problem that a large impact sound is generated by being adsorbed vigorously by 104a.

  Therefore, in order to reduce the noise at the time of clutch meet, it is desirable that the axial spring constant of the elastic body 113 has a non-linear characteristic that increases as the armature 105 approaches the end face 104 a of the rotor 104. An example of a coupling for an electromagnetic clutch that realizes such nonlinear characteristics is shown in FIG.

  That is, the electromagnetic clutch coupling 120 shown in FIG. 9 includes a hub 121 fixed to the distal end portion of the rotating shaft 106, a disk-like plate 123 coupled to the hub 121 via a plurality of metal fittings 122, and the plate. 123, an engagement pin 124 that is loosely inserted into a fitting hole formed in 123 and fixed at a coupling hole 105a formed in the armature 105, and a vibration isolating rubber 125 attached to the outer periphery thereof.

  According to this configuration, when the armature 105 is attracted to the end face 104 a of the rotor 104 by energization of the exciting coil 102, the flange portion 124 a of the engaging pin 124 that is axially displaced integrally with the armature 105 is The main elastic portion 125a of the anti-vibration rubber 125 is compressed and deformed. That is, the anti-vibration rubber 125 exhibits a non-linear spring characteristic in which the spring constant increases as the armature 105 approaches the end face 104a of the rotor 104 due to compression, and the impact when the armature 105 is attracted to the rotor 104 is absorbed. Therefore, noise is effectively reduced (see, for example, Patent Document 2 below).

  However, according to the electromagnetic clutch coupling 120 shown in FIG. 9, fluctuations in transmission torque (torsional vibration) between the armature 105 attracted by the rotor 104 and the plate 123 on the hub 121 (rotary shaft 106) side. This absorption depends on the compression deformation of the neck portion 125b of the anti-vibration rubber 125. Therefore, there is a problem that a sufficient vibration reduction effect cannot be obtained.

JP 2001-124111 A JP 07-174167 A

  The present invention has been made in view of the above points, and its technical problem is to reduce electromagnetic shock noise during clutch meet and to absorb torsional vibration during operation. It is to provide a coupling for a clutch.

As a means for effectively solving the technical problem described above, the electromagnetic clutch coupling according to the first aspect of the present invention surrounds the exciting coil and is disposed so as to be opposed to the rotor rotatably supported by the housing in the axial direction. A coupling for an electromagnetic clutch provided between an armature that is brought into contact with or separated from the end face of the rotor by energization or de-energization of the excitation coil and a rotation shaft inserted through the housing. A hub attached to the armature, an outer ring coupled to the opposite side of the rotor in the armature, and an elastic body disposed on the opposite side of the armature to the rotor and elastically connecting the outer ring and the hub A cylindrical shape provided integrally with the elastic body in a state of passing through the radial intermediate portion of the elastic body in the axial direction A locked member, a first shaft portion inserted into a locking member holding hole provided in the armature in a state capable of axial relative displacement, and a first shaft portion inserted into the locked member so as to be axially displaceable. A locking member having a biaxial portion, wherein the locking member is configured such that the first shaft portion can protrude through the locking member holding hole and protrude toward the rotor, and the armature is attached to the rotor. The end portion on the rotor side of the locked member that is displaced toward the rotor side due to the deformation of the elastic body to the rotor side due to magnetic attraction is the first shaft portion of the locking member and the first shaft portion. It is brought into contact with a collar portion formed between the two shaft portions.

According to the above configuration, when the armature is attracted to the rotor by energization of the exciting coil, the elastic body is deformed to the rotor side between the outer ring coupled to the opposite side of the rotor in the armature and the hub on the rotating shaft side. Is done. Then, during the movement process of the armature , the first shaft portion of the locking member protruding from the locking member holding hole provided in the armature is brought into contact with the rotor and provided at the radial intermediate portion of the elastic body. The engaged member is displaced to the rotor side as the elastic body is deformed to the rotor side, and the end of the locked member on the rotor side comes into contact with the hook portion of the engaging member , Since the deformation of the elastic body toward the rotor is partially limited, the spring constant of the elastic body increases at that time. For this reason, the spring constant is low when the armature is initially displaced by energizing the exciting coil, and the spring constant increases when the armature is attracted to the rotor, and the acceleration of the armature due to magnetic attraction is suppressed. Thus, the impact caused by the clutch meat is effectively mitigated. Further, the torsional vibration input in the operation state in which the armature is attracted to the rotor is effectively absorbed by the elastic body being sheared and deformed in the torsional direction (circumferential direction).

A coupling for an electromagnetic clutch according to a second aspect of the present invention is the electromagnetic clutch coupling according to the first aspect, wherein a locking member holding hole that is opened in the armature and through which the first shaft portion of the locking member is inserted is provided in the armature. extending in an arc shape around the axis, the locking member, characterized in that a relative displaceable in the circumferential direction by a predetermined range with respect to the armature.

  According to this configuration, in the state where the armature is attracted to the rotor, the shear deformation in the torsional direction of the elastic body due to the variation of the transmission torque is not hindered by the locking member and the locked member. (Torsional vibration) Absorption effect is obtained.

According to a third aspect of the present invention, there is provided the electromagnetic clutch coupling according to the second aspect , wherein a cam member is provided in the locking member holding hole, and the cam member is in a torsional direction of the elastic body by the input torque. A locking member that is displaced relative to the circumferential direction together with the member to be locked along with the shear deformation of the member and a slidable slope, and when the input torque exceeds a predetermined range, the locking member rides on the slope. Is pushed out to the rotor side .

According to this configuration, as the elastic body is sheared and deformed in the torsional direction by the torque input in a state where the armature is attracted to the rotor, the elastic body is integrally provided in the radial intermediate portion of the elastic body. When the amount of displacement of the locking member that is displaced relative to the armature in the circumferential direction together with the locked member increases beyond a predetermined range, the locking member rides on the slope of the cam member and is pushed out. Thus, the rotor is pressed and the rotor and the armature are separated to exert a torque limiter function for interrupting torque transmission from the rotor to the armature.

  According to the electromagnetic clutch coupling of the first or second aspect of the present invention, the axial spring constant is low at the initial stage of displacement of the armature due to the energization of the exciting coil, and the axial direction when the armature is attracted to the rotor. Since the spring constant becomes a non-linear characteristic, the impact noise at the time of clutch meet can be reduced, and the fluctuation of the transmission torque can be effectively absorbed by the torsional direction shear deformation of the elastic body.

  In addition, according to the electromagnetic clutch coupling according to the third aspect of the invention, torque transmission is interrupted when an excessive torque is generated due to an abnormality such as the rotation shaft being locked, thereby effectively preventing damage to the device. can do.

1 is a schematic sectional perspective view showing an embodiment of a coupling for an electromagnetic clutch according to the present invention by cutting along a plane passing through an axis. 1 is a half sectional view showing an embodiment of a coupling for an electromagnetic clutch according to the present invention, cut along with a part of the electromagnetic clutch on a plane passing through an axis. It is a section perspective view of the separation state which cuts and shows an embodiment of a coupling for electromagnetic clutch concerning the present invention by a plane which passes along an axis. In the embodiment of the coupling for an electromagnetic clutch according to the present invention, the armature, the engaging member, and the cam member are cut in a perspective view in a separated state shown by cutting along a cylindrical surface concentric with the armature. 1 is a half cross-sectional view of a state immediately before a clutch meet, showing an embodiment of a coupling for an electromagnetic clutch according to the present invention cut along with a part of an electromagnetic clutch on a plane passing through an axis. 1 is a half sectional view of a clutch meet state showing an embodiment of a coupling for an electromagnetic clutch according to the present invention cut along with a part of an electromagnetic clutch on a plane passing through an axis. 1 is a half cross-sectional view of a torque limiter operating state showing an embodiment of a coupling for an electromagnetic clutch according to the present invention cut along with a part of an electromagnetic clutch on a plane passing through an axis. FIG. 10 is a half sectional view showing an example of a coupling for an electromagnetic clutch according to a conventional technique, cut along with a part of the electromagnetic clutch on a plane passing through an axis. FIG. 10 is a half cross-sectional view showing another example of the coupling for an electromagnetic clutch according to the prior art, cut along with a part of the electromagnetic clutch on a plane passing through the axis.

  Hereinafter, preferred embodiments of a coupling for an electromagnetic clutch according to the present invention will be described with reference to the drawings. In the following description, “front side” refers to the left side in FIGS. 1 to 3 and FIGS. 5 to 7, and “back side” refers to the opposite side.

  In FIG. 2, reference numeral 1 is a front side end portion of a compressor housing in a vehicle cabin air conditioner, reference numeral 2 is a non-rotating exciting coil fixed to the housing 1, and reference numeral 4 is a ball on the housing 1. A rotor made of a magnetic metal supported rotatably through a bearing 3, reference numeral 5 is an armature as a clutch disk made of a magnetic metal arranged close to and opposed to the front side of the rotor 4, and reference numeral 6 is A rotating shaft that is inserted into the housing 1 and operates an internal refrigerant compression mechanism (not shown), and reference numeral 10 is a coupling. The rotor 4 has a pulley (not shown) on the outer periphery, for example, and rotates when a driving force of the internal combustion engine is applied via a belt (not shown) wound around the pulley.

  The coupling 10 includes a hub 11 attached to the end of the rotating shaft 6, an outer ring 12 that is concentrically disposed on the outer peripheral side thereof and attached to the front side of the armature 5, and the hub 11 and the outer ring 12. And an elastic body 13 that elastically connects the two.

  As shown in FIGS. 1 and 3, the hub 11 includes an inner peripheral boss portion 11 a, a disk-shaped flange 11 b that extends from an end portion on the front side in the axial direction to the outer peripheral side at a right angle to the shaft center, The rim portion 11c extends from the outer diameter end portion to the front side, and is fixed to the end portion of the rotating shaft 6 at the boss portion 11a.

  The outer ring 12 is manufactured by press-molding a metal plate, and as shown in FIG. 3, is formed at equal intervals in the circumferential direction from the sleeve portion 12 a and the rear side end portion to the outer diameter side. And a coupling flange portion 12b each having a coupling hole 12c. The outer ring 12 is coupled to the front side of the armature 5 via a plurality of rivets 7 inserted across the coupling hole 12c of the coupling flange portion 12b and the corresponding coupling hole 5a provided in the armature 5. Has been.

  The elastic body 13 is formed in a ring shape from a rubber-like elastic material (rubber material or synthetic resin material having rubber-like elasticity), and the inner diameter portion is integrally added to the outer peripheral surface of the rim portion 11 c of the hub 11. The outer diameter portion is integrally vulcanized and bonded to the inner peripheral surface of the sleeve portion 12 a of the outer ring 12. This elastic body 13 holds the armature 5 in a state slightly separated from the end face 4a of the rotor 4 toward the axial front side in the non-energized state of the exciting coil 2 shown in FIG. The magnetic attraction force acting between the armature 5 magnetized by the magnetic field and the rotor 4 is allowed to move in the axial direction and be attracted to the end face 4a of the rotating rotor 4, and in the attracted state, the armature 5 side Torque is transmitted from the shaft to the rotating shaft 6 side.

  In addition, an elastic protrusion 13 a protruding toward the armature 5 is formed on the inner periphery of the elastic body 13 by a rubber-like elastic material continuous with the elastic body 13. The elastic protrusion 13 a is formed of the armature 5. Is held in a position spaced apart from the end surface 4a of the rotor 4 in the axial direction by the elasticity of the elastic body 13 so as to come into pressure contact with the front end surface of the armature 5.

  The armature 5 is provided with a plurality of elongated locking member holding holes 5b extending in a circular arc shape centered on the axis O at predetermined intervals in the circumferential direction. The stop member 14 is held in a state of being inserted so as to be capable of relative displacement in the axial direction. Specifically, the locking member 14 is made of, for example, a synthetic resin material having a good slidability, and is axially pierced through the locking member holding hole 5b and protruding to the back side (the rotor 4 side). A first shaft portion 14a at one end, a second shaft portion 14b extending to the opposite side (front side), a first flange portion 14c and a second flange portion between the first shaft portion 14a and the second shaft portion 14b. 14d. The second collar part 14d is located on the front side of the first collar part 14c, and has a larger diameter than the second shaft part 14b and a smaller diameter than the first collar part 14c.

  A plurality of cylindrical members to be locked 15 are integrally formed in the radially intermediate portion of the elastic body 13 at intervals corresponding to the locking member holding holes 5b of the armature 5 so as to penetrate the elastic body 13 in the axial direction. Is provided. A second shaft portion 14b of the locking member 14 held in the locking member holding hole 5b is inserted into the locked member 15 so as to be axially displaceable. The end on the back side opposes in the axial direction in a state where it can abut against the end surface of the second flange 14d of the locking member 14.

  Further, a cam member 16 is integrally attached to the locking member holding hole 5b of the armature 5 so as to close the opening on the front side thereof, and an opening 16a extending in an arc shape is opened in the cam member 16. At the same time, a slope 16b is formed on the back surface to increase the axial thickness toward both ends in the circumferential direction. When the locking member 14 is displaced relative to the cam member 16 in the circumferential direction beyond the predetermined range, the first flange portion 14c slides so as to ride on the inclined surface 16b, so that the rotor 4 side To be pushed out.

  The operation of the electromagnetic clutch including the coupling 10 configured as described above will be described. The rotor 4 is rotated by being given the driving force of the internal combustion engine via an endless belt (not shown), while the exciting coil 2 is not energized, the armature 5 is held away from the end face 4a of the rotor 4 with a gap G, so that the torque to the rotary shaft 6 is cut off, that is, the refrigerant compression mechanism inside the compressor is stopped. Is in a state.

  From this state, when an exciting current is supplied to the exciting coil 2, the rotor 4 and the armature 5 are magnetized by the magnetic field generated in the exciting coil 2, so that the armature 5 is rotated by the magnetic attraction force acting between them. 4 is moved in the axial direction toward the end face 4a.

  At this time, as shown in FIG. 2, in the initial stage of movement when the rotor 4 and the armature 5 are separated by the gap G, the magnetic attractive force acting between the two is small, but is held in the locking member holding hole 5 b of the armature 5. Since the locking member 14 is movable in the axial direction, the cylindrical locked member 15 into which the second shaft portion 14b of the locking member 14 is inserted has the elastic body 13 in the axial direction. Is not restrained. Therefore, between the sleeve portion 12a of the outer ring 12 that is axially displaced toward the rotor 4 integrally with the armature 5 and the rim portion 11c of the hub 11 that is fixed to the rotary shaft 6 and is not displaced in the axial direction, Since the entirety is axially sheared and the axial spring constant is sufficiently low, the armature 5 can easily start axial movement toward the rotor 4 side.

  Further, as the armature 5 approaches the end face 4a of the rotor 4, the magnetic attractive force acting between them increases nonlinearly, but the locked member provided integrally in the radial intermediate portion of the elastic body 13 15 is axially displaced toward the back side along with the axial shearing deformation of the elastic body 13, and the end portion on the back side eventually comes into contact with the end surface of the second flange portion 14 d of the locking member 14, and this is moved to the back side. As shown in FIG. 5, the first shaft portion 14 a of the locking member 14 is slidable with the end surface 4 a of the rotor 4 in advance of the clutch meat where the armature 5 is attracted to the end surface 4 a of the rotor 4. Axial displacement of the locked member 15 toward the back side is restricted via the locking member 14. Therefore, the axial shear deformation of the portion 13b of the elastic body 13 between the locked member 15 and the rim portion 11c of the hub 11 is restricted, and the space between the locked member 15 and the sleeve portion 12a of the outer ring 12 is restricted. Since the axial shear deformation is continued only in the portion 13c, the spring constant of the elastic body 13 becomes high at that time, and the acceleration of the armature 5 due to the non-linear increase in the magnetic attractive force is suppressed. The impact at the time of clutch meet of the armature 5 and the rotor 4 to be shown is alleviated, and the impact sound is effectively suppressed.

  Then, the rotational torque of the rotor 4 is transmitted from the armature 5 to the rotary shaft 6 through the outer ring 12, the elastic body 13 and the hub 11 by the clutch meet, and the refrigerant compression mechanism inside the compressor, that is, the cabin air conditioning. The device is in operation.

  At this time, the first shaft portion 14a of the locking member 14 that is in contact with the end surface 4a of the rotor 4 is slidable with respect to the end surface 4a of the rotor 4, and the armature 5 through which the locking member 14 is inserted. Since the locking member holding hole 5b extends in an arc shape, the locking member 14 and the locked member 15 engaged with the locking member 14 by insertion are accompanied by the shear deformation of the elastic body 13 in the torsional direction. And can be displaced in a predetermined range in the circumferential direction. For this reason, the elastic body 13 can be subjected to shear deformation in the twisting direction (circumferential direction). Therefore, an impact caused by a sudden input of the rotational torque of the rotor 4 to the armature 5 by the clutch meat or transmission during driving. The torque fluctuation is effectively mitigated by the torsional direction shear deformation of the elastic body 13.

  Next, when the exciting current to the exciting coil 2 is cut off from the clutch connection state of FIG. 6 in which the armature 5 is attracted to the rotor 4, the magnetic attracting force between the rotor 4 and the armature 5 is eliminated. Due to the restoring force of the armature 5, the armature 5 moves away from the end surface 4 a of the rotor 4 to the front side and returns to the position shown in FIGS. 1 and 2. For this reason, transmission of the rotational torque from the rotor 4 via the armature 5 and the coupling 10 is interrupted, and the rotation of the rotating shaft 6 is stopped, that is, the refrigerant compression mechanism is stopped.

  When the armature 5 returns, the front end face of the armature 5 comes into contact with a plurality of arc-shaped elastic ridges 13 a formed on the inner periphery of the elastic body 13 to define the return position of the armature 5. No collision noise caused by metal contact.

  Further, in the clutch connection state of FIG. 6 in which the armature 5 is adsorbed to the rotor 4, for example, when the rotary shaft 6 is locked due to seizure of the refrigerant compression mechanism inside the compressor, the driving force from the internal combustion engine is received. When an excessive torque is input between the rotor 4 and the rotor 4 rotated in this manner, the circumferential displacement of the locked member 15 and the locking member 14 inserted into the locked member 15 due to the torsional direction shear deformation of the elastic body 13. As the distance increases, the first flange portion 14c of the locking member 14 rides on the slope 16b of the cam member 16 due to an increase in the circumferential displacement of the locking member 14 relative to the armature 5 (cam member 16). As a result, the locking member 14 is pushed out to the back side, and the first shaft portion 14 a presses the end surface 4 a of the rotor 4. Then, when this pressing force becomes larger than the magnetic attractive force between the rotor 4 and the armature 5, in other words, when the input torque exceeds an allowable value, as shown in FIG. Since the armature 5 is separated from the end face 4 a of the rotor 4, it exerts a torque limiter function that blocks torque input from the rotor 4.

  For this reason, even if the rotating shaft 6 is locked, the rotor 4 continues to rotate smoothly, and the belt that transmits the driving force from the internal combustion engine to the rotor 4 is not damaged by excessive torque. Since other auxiliary machines such as the cooling water circulation pump and the alternator that are operating are continuously operated, it is possible to prevent the occurrence of a situation in which the internal combustion engine stops and the automobile cannot run.

DESCRIPTION OF SYMBOLS 1 Housing 2 Excitation coil 4 Rotor 5 Armature 6 Rotating shaft 10 Coupling 11 Hub 12 Outer ring 13 Elastic body 14 Locking member 14a First shaft part (one axial end)
14b Second shaft portion 14c First flange portion 14d Second flange portion 15 Locked member 16 Cam member 16a Opening portion 16b Slope

Claims (3)

An armature that surrounds the excitation coil and is axially opposed to a rotor that is rotatably supported by the housing and that is in contact with or separated from the end surface of the rotor by energization or de-energization of the excitation coil, and is inserted into the housing A coupling for an electromagnetic clutch provided between the rotating shaft, a hub attached to the rotating shaft, an outer ring coupled to the opposite side of the rotor in the armature, and the rotor in the armature An elastic body that is disposed on the opposite side and elastically connects the outer ring and the hub, and a cylindrical shape that is provided integrally with the elastic body in a state of passing through a radial intermediate portion of the elastic body in the axial direction. And a first shaft that is inserted in a locking member holding hole provided in the armature in a state in which the axial relative displacement is possible. And a locking member having a second shaft portion that is inserted into the locked member so as to be capable of relative displacement in the axial direction, wherein the first shaft portion penetrates the locking member holding hole. The rotor side of the locked member that can project to the rotor side and displaces to the rotor side due to deformation of the elastic body toward the rotor side as the armature is magnetically attracted to the rotor. The end portion of the electromagnetic clutch is in contact with a flange portion formed between the first shaft portion and the second shaft portion of the locking member. Locking member holding hole which the first shaft portion of the locking member is inserted is opened in the armature, extends in an arc shape around the axis of the armature, the locking member is circumferentially with respect to said armature 2. The electromagnetic clutch coupling according to claim 1, wherein relative displacement is possible within a predetermined direction range. A cam member is provided in the locking member holding hole, and the cam member is slidable with the locking member that is displaced in the circumferential direction together with the locked member in accordance with the shear deformation in the torsional direction of the elastic body by the input torque. The electromagnetic clutch coupling according to claim 2, further comprising: a sloping surface, wherein when the input torque exceeds a predetermined range, the locking member rides on the sloping surface and is pushed out to the rotor side .

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