Denso Corporation

Nippondenso Co., Ltd.

Denso Corpora Tion

Toshihiro Hayashi

Toshihiro Konishi

Yasuo Tabuchi

Shigeyoshi Sakuraba

Takayuki Hirose

Junichi Ohguchi

Yuuichi Aoki

Akira Kishibuchi

Kiyoshi Kurohata

Kazuma Tachibana

Hiroki Nagahashi

Hiroyasu Sakamoto

Masashi Tobayama

Manabu Saiki

Kiyomi Okuda

Hiroshi Nakajima

Takuo Sakai

Haruhisa Shibata

Yusuke Sakurai

Satoshi Iha

Kazuhiko Ohtsuka

Youhei Kushida

An armature is configured to come into contact with an actuator due to magnetic attraction force. An outer plate is fixed to an armature, the outer plate being located on an opposite side of the armature from the actuator, the outer plate being configured to rotate together with the armature. An inner hub is located between the armature and the outer plate to be movable in a direction along a rotation axis, the inner hub being fixed to a driven device. A rubber member is disposed between the inner hub and the outer plate to give an urging force to the inner hub and the outer plate in a direction away from each other. This electromagnetic clutch is configured such that the urging force of the rubber member non-linearly increases as the actuator and the armature approach each other due to the magnetic attraction force.

Electromagnetic clutch

A power transmission device includes an electromagnet, a rotor, an armature and a hub. The hub couples the armature to a shaft of a drive-subject device. The hub includes: an outer hub that is coupled to the armature; a boss portion that is coupled to the shaft; an inner side plate-shaped portion that extends from the boss portion toward a radially outer side; and an inner plate that is placed between the outer hub and the inner side plate-shaped portion. The inner side plate-shaped portion and the inner plate are formed integrally in one piece. At least one of the inner side plate-shaped portion and the inner plate is formed by a member that is configured to deform or melt with heat generated by friction between the rotor and the armature when the shaft of the drive-subject device is locked at a time of energizing the electromagnet.

Power transmission device

An armature includes an inner plate located on an inner side of a groove and an outer plate located on an outer side of the groove. The hub includes: an outer hub; an inner hub that is coupled to a shaft; and a primary elastic member that is interposed between the inner hub and the outer hub and is configured to exert an elastic force to the outer hub in a direction away from a rotor. The outer hub includes an outer side coupling portion that is opposed to the outer plate and the inner plate and is coupled to the outer plate. The hub includes a secondary elastic member that is clamped between: the outer plate and the inner plate located on one side of the secondary elastic member; and the outer side coupling portion located on another side of the secondary elastic member.

A power transmission device includes an electromagnet, a rotor, an armature and a hub that couples the armature to a shaft of a driving target device. The hub includes an outer hub coupled to the armature, an inner hub coupled to the shaft, and an elastic member interposed between the outer hub and the inner hub. An outer peripheral side of the inner hub includes plural extending parts each extending outward in a radial direction. An inner peripheral side of the outer hub includes an inner peripheral side wall that overlaps with the extending parts in a rotational direction and surrounds the extending parts. The elastic member is disposed in an unbonded state with respect to at least one of the inner hub and the outer hub between the outer peripheral side of the inner hub and the inner peripheral side of the outer hub.

An electromagnetic clutch includes: a driving-side rotatable body that is rotated about an axis of a rotatable shaft of a drive-subject device; and a driven-side rotatable body that is placed on one side of the driving-side rotatable body in an axial direction. The electromagnetic clutch includes a flat spring that is formed to be rotatable integrally with the rotatable shaft of the drive-subject device and is joined to the driven-side rotatable body. The electromagnetic clutch includes a blocking member that is installed to the flat spring. A primary through-hole is formed in the driven-side rotatable body. A secondary through-hole is formed in the flat spring. Switching between coupling and decoupling between driving-side rotatable body and the driven-side rotatable body is made through elastic deformation of the flat spring. The blocking member closes the secondary through-hole.

A power transmission device that transmits a rotational driving force outputted from a driving source to a target device to be driven includes: a driving rotor rotated by the rotational driving force; a driven rotor that rotates with a rotary shaft of the target device; and a connection member. The connection member has a plate shape extending perpendicular to the rotary shaft. The connection member is connected at least one of the driving rotor and the driven rotor, and is capable of connecting the driving rotor and the driven rotor to each other. The connection member has a through hole, and the driven rotor has an overlapping portion disposed overlapping with the through hole when viewed in the axial direction of the rotary shaft.

The electromagnetic clutch comprises a rotor connected to a drive source, an inner hub connected to a device that follows, an outer plate provided on the outside of the inner hub so as to enclose it, an armature coupled to the outer plate and opposing the rotor, an elastic member provided between the inner hub and the outer plate and adhered thereto, and an electromagnetic coil for, when magnetized, attracting the armature together with the outer plate to make them come into contact with the rotor, and when demagnetized, separating the outer plate and the armature from the rotor. Because of the configuration in which the armature and the outer plate are coupled in a heat-transmissible manner, a part of elastic member is formed so that heat is transmitted from at least a part of the armature to the part of the elastic member as if they are one piece.

Electromagnetic clutch with elastic member easily melted

An electromagnetic clutchhas a construction in which an armatureand a platesandwich an elastic memberbetween them. A spring portionis formed in the plateand an elastic memberis so disposed as to cover a front side of the spring portiontoo. Elastic membersandare disposed in a thin film form on an inner surface of elongated holesof the armatureand the innermost and outermost diameter portionsandof the armatureThe distal end of each elastic memberandis extended to the same plane as an end faceof the armatureon the rear side or to a position somewhat protruding from the end face on the rear side.

In the disclosed electromagnetic clutch, a bent porion () of a plate () comes into contact with an armature () attempting to move beyond a predetermined movable range, thereby restricting the movement of the armature (). As a result, if an elastic member () is fused, a trouble is prevented which otherwise might be caused by the movement of the now-unsupported armature () beyond a predetermined movable range.

An electromagnetic clutch reduces clutch operating noise at a low cost by utilizing elastic members which are suited to a spring force of a leaf spring. An approximate nonagonal leaf spring has an outer ring portion, attachment portions connected to a hub, and connecting portions. Under the outer ring portion, securing portions of an armature are disposed. First elastic members are disposed at intermediate points of the securing portions, and a second elastic member is disposed in a gap between the leaf spring and the hub along an axial direction. When actuating the electromagnetic clutch, the leaf spring compresses the second elastic member, and when stopping the electromagnetic clutch, the armature collides with the first elastic member so that an axial position of the armature is secured.

A torque limiting mechanism includes an axial space formed in a cylindrical wall of a pulley, and a pin protruding and extending from a back surface of a discharge disc. The pin is inserted into the axial space, and a rubber damper is installed between the inner surface of the axial space and the pin. When torque difference between the pulley and the discharge disc exceeds a threshold, a root portion of the pin is broken to separate the discharge disc from the pulley, thereby interrupting rotation transmission from the pulley to the discharge disc.

Rotation transmitter having torque limiting mechanism

In order to reduce an electromagnetic clutch in an axial size, a ring-shaped leaf spring connects an armature to a hub. The leaf spring has an outer ring portion connected to the armature, an attachment portion connected to the hub and located inner than the outer ring portion, and a connecting portion for connecting the outer ring portion and the attachment portion. A plurality of rivets of the armature are disposed at the outer ring portion. An embossed portion for generating an initial deflection on the leaf spring is disposed at an intermediate portion between the rivets in the circumferential direction of the outer ring portion.

Coil-rotation type electromagnetic clutch

A spring plate member is connected to a hub. The spring plate member includes a plate spring portion generating a resilient force to separate an armature from a rotor, and an outer ring portion, which faces the armature. An elastic member is provided between the armature and the outer ring portion for connecting the armature directly with the outer ring portion. Thus, operation noises of the electromagnetic clutch and a compressor are efficiently reduced. Further, the axial dimension of elastic member can be made much smaller than that of the conventional cylindrical elastic member.

An electromagnetic clutch has an armature, a rotor housing accommodating a stator housing and an exciting coil having negative and positive terminals. A passage is formed to extend from an outer peripheral surface of the stator housing to the negative terminal and the positive terminal. The passage is filled with a conductive metal member having a melting point lower than that of the stator housing between the outer surface of the stator housing and the negative terminal. When frictional heat generated between the armature and the rotor housing exceeds a preset value, the metal member melts and flows to the positive terminal, thereby short-circuiting the coil. As a result, a fuse between a power source and the clutch is fused, thereby turning off the clutch. Therefore, the clutch does not need to have a thermal fuse therein and is reduced in size without increasing power consumption.

An electromagnetic clutch for use with a compressor for an automobile air conditioning system includes a back cover provided at an end wall (26) of an armature (15) which moves to engage and disengage a rotor. The back cover has visored slits (30) with visors (30a) which align with arcuate slots (24) of an armature (28). The air between the armature and the rotor is released through the slits to prevent over compression of the air when the armature is attracted to the rotor. The visor of the back cover prevents an oil leaking from the compressor from invading into the contacting surfaces of the clutch through the arcuate slots of the armature (15).

Growing community of inventors

Kariya, Japan

Toshihiro Hayashi