JPH08210386A - Electromagntic clutch - Google Patents

Abstract

PURPOSE: To improve electromagnetic responsiveness, and to simplify constitution by fitting a semi-circularly expanded guide leg part provided with an engagement claw in an oblong fitting hole for engagement. CONSTITUTION: A guide leg part 6a of an armature hub 6 is freely fitted to a plurality of fitting holes 2 which are concentrically cut in a gear 1. A key- shaped elastic member 5 such as a leaf spring is fixed to the inner side of the gear 1, and the tip of the elastic member 5 is engaged with and locked to a recess of the armature hub 6. A clutch body 8 side is assembled by fitting a bearing 10 and a cylindrical body 9 to a yoke where an electromagnet 11 is built in, and when the current flows, an armature 7 is attracted by the electromagnet 11, and the engagement claws are engaged with each other by being slid through the guide of the semi-circular guide leg part 6a and the fitting hole 2 against the elastic force of the elastic member 5 of the gear 1 so as to be brought into press contact with the cylindrical body 9 side. The turning motion of the gear 1 is smoothly transmitted to a connecting member to be connected to a rotary shaft 13.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic clutch which is a coupling device in which two rotating bodies provided so as to be rotatable relative to each other are operated to move toward and away from each other. 2. Description of the Related Art Conventionally, of two rotary discs formed of a ferromagnetic material and arranged coaxially, a rotary motion is transmitted to a rotary disc which is spaced from a rotary disc connected to a drive source. An electromagnetic clutch is known. As such an electromagnetic clutch, tooth projections that mesh with the facing surfaces of both rotary disks are not provided, but the opposing surfaces of both rotary disks are brought into contact with each other by the attractive force of the electromagnet, and the rotational force is transmitted by the frictional force of both surfaces. Method and tooth rows that mesh with each other's abutment surface are provided, and one of the rotary disks is attracted by magnetic attraction force and the locking parts are engaged to transmit the rotational force to the other rotary disk to rotate simultaneously. It is known to do this. For example, in the "electromagnetic coupling device" disclosed in Japanese Utility Model Laid-Open No. 1-168027, an annular leaf spring is arranged between an armature attracted by an electromagnet and an armature hub. The (annular member) is biased toward the armature hub side, and the projection of the collar is engaged and fixed in the engagement hole formed in the annular leaf spring. When the armature is attracted by the operation of the electromagnet, the collar also moves together with the armature hub, and the rotation transmission between the rotor and the armature hub (driving gear) is performed. The protrusion of this collar is fixed to the armature hub together with the annular spring. Further, in Japanese Unexamined Patent Publication No. 2-46327, three holes are bored in an armature loosely fitted in an armature hub, and the tip of the arm of the armature hub is engaged with the hole of the armature to connect with the rotor. Is disclosed. In this case, the armature of the armature hub and the hole of the armature are engaged with each other by sliding on the shaft of the armature hub by the operation of the electromagnet. The former requires a collar member for fixing the annular leaf spring to the armature hub, which complicates the configuration, increases the number of parts such as the annular leaf spring, and is expensive. Became. In the latter, the arm (projection) of the armature hub fixed to the drive gear is used as an engaging projection, and the movement of this armature cannot be performed smoothly, which also causes a delay in electromagnetic response. Moreover,
In both cases, the two rotating disks are engaged by inserting the projection into the engaging hole, so that there is inevitably a time lag until the engagement with respect to the operation of the electromagnet. Further, if the drive gear and the armature are engaged only by the leaf spring, the load on the leaf spring is large and the torque transmission is insufficient.
Moreover, the engaging portions of both are often made of metal or the like, which is heavy and expensive. An object of the present invention is to provide an electromagnetic clutch excellent in electromagnetic response and simple in construction. Another object of the present invention is to provide an electromagnetic clutch which has a simple structure formed of synthetic resin and is easy to assemble. Another object is to provide an electromagnetic clutch that can smoothly guide an armature hub molded of synthetic resin to a gear or a pulley so as to smoothly engage with an engaging tooth claw of the clutch body. It is provided. The above object of the present invention can be achieved by the following constitution. The structure is such that a plurality of elliptical fitting holes are concentrically formed, and a gear or pulley provided with a groove for fixing an elastic member for urging an armature hub inside, and a fitting hole of the gear or pulley is loosely fitted. A plurality of guide legs are extended, a plurality of engaging tooth claws are projected on the opposite surface, and a recess for locking the tip of the elastic member is bored on the gear or pulley side of the cylindrical portion, which is attracted by the electromagnet. An armature and an electromagnet formed by winding a winding coil are arranged in a fixed frame on the outer periphery, and a bearing is connected to a cylinder having a plurality of protruding engaging teeth engaged with the engaging teeth of the armature hub. A clutch main body, which attracts the armature facing the electromagnet by energizing the electromagnet, resists the biasing force of the elastic member of the gear or pulley, and The inner leg is slid in the fitting hole of the gear or the pulley to move the armature, and the engaging tooth claw of the armature hub and the engaging tooth claw facing the clutch body are engaged to rotate the armature. It is something to convey. The above object can be achieved by molding a gear or the like with a synthetic resin. Further, the above object can be achieved by mutually molding the armature hub and the engaging tooth claws that mesh with the armature hub. [0009] The electromagnetic clutch of the present invention includes the engaging tooth claws. Since the armature hub and the gear or the pulley are engaged with each other by fitting the guide leg portion protruding in the arc shape of the armature hub into the long arc-shaped fitting hole of the gear or the pulley, the engagement of the both is prevented. It is reliable and there is no play in torque transmission as compared to the engagement of only elastic members, eg leaf springs. Further, since the gear or the pulley is made of synthetic resin or the like, the elastic member can be easily attached to the inside groove of the gear. Moreover, this armature is made of a ferromagnetic material and is integrally formed with the armature hub. Further, the engaging tooth claws of the armature hub and the engaging tooth claws of the clutch body can be surely engaged with each other. Also, by forming the gear or pulley, the armature hub, and the rotating cylinder of the clutch body from synthetic resin,
It can be easily manufactured. Embodiments of the electromagnetic clutch of the present invention will be described with reference to the drawings. 1 is a right side view of a gear according to an embodiment of an electromagnetic clutch of the present invention. 2A and 2B are armature drawings of an embodiment used in the electromagnetic clutch of the present invention. FIG. 2A is a left side view, FIG. 2B is a sectional view, FIG. 2C is a plan view, and FIG. . FIG. 3 is a sectional view of an embodiment of the electromagnetic clutch of the present invention. FIG. 4A is a left side view of FIG. (B) is a right side view of FIG. 3. In the gear 1 of the electromagnetic clutch of the embodiment shown in FIG. 1, three long arc-shaped fitting holes 2 are concentrically formed. An elastic member such as a leaf spring can be fixed to the inside of the gear 1 and the tip of the elastic member 5 faces the fitting hole 2. 6 is an armature hub,
A guide leg portion 6 that can be loosely fitted in the fitting hole 2 of the gear 1.
A is projected, and a hollow 6c is formed in this cylindrical portion 6b so that the tip of the elastic member 5 is engaged. An armature 7 is fixed to the outer peripheral edge of the armature hub 6. For example, a plurality of protrusions provided on the armature hub 6 can be fitted into the engagement holes of the armature 7 and the heads of these protrusions can be pressed and caulked to be fixed. A plurality of engaging tooth claws 6d are projected on the side of the clutch body 8 of the cylinder 6b of the armature hub 6. In the illustrated embodiment, three are provided.
The gear 1 and the armature hub 6 can be molded of synthetic resin such as nylon, but the armature hub 6 may be integrally formed of a ferromagnetic material. Reference numeral 9 is a cylindrical body fitted in the bearing 10 of the clutch main body 8 and engaging tooth claw 6 of the cylinder 6b of the armature hub 6.
A large number of engaging tooth claws 9a that mesh with d are planted. The rotating cylinder 9a of the cylindrical body 9 is connected to the bearing 10 of the clutch body 8, and the rotating cylinder 9b rotates together with the cylinder 6b of the armature hub 6. It is loosely fitted. The shape of the end of the bearing 10 is non-circular and is adapted to engage with the shaft hole of the other connecting member. Reference numeral 11 denotes an electromagnet having a coil wound therein, which is built in the yoke of the clutch body 8.
The clutch body 8 is made of a metal plate. The fixed frame 12 that fixes the electromagnet 8 is integrally formed by drawing. The operation of the electromagnetic clutch of the present invention will be described based on an embodiment. The guide leg portion 6a of the armature hub 6 is loosely fitted into the plurality of fitting holes 2 formed on the concentric circle of the gear 1. Next, a key-shaped elastic member 5 such as a leaf spring is fixed inside the gear 1. The tip of the elastic member 5 is engaged and locked in the recess 6c of the armature hub 6. The armature 7 is attached to each protrusion provided on the outer peripheral edge of the armature hub 6.
The engaging holes of are engaged and fixed. On the other hand, on the clutch body 8 side, a bearing 10 and a cylindrical body 9 are fitted to a yoke having an electromagnet 11 built therein, and the rotary cylinder 9a of the cylindrical body 9 is inserted into the cylinder 6b of the armature hub 6, respectively. The engaging tooth claw 9a and the engaging tooth claw 6d are arranged to face each other. When a current is supplied to the electromagnetic clutch of the present invention, the armature 7 is attracted by the operation of the electromagnet 11 and resists the elastic force of the elastic member 5 of the gear 1 so that the arcuate guide leg portion 6a and the fitting hole 2 are formed. As the guide body slides and presses against the cylindrical body 9 side of the clutch body 8 to engage the engaging tooth claws 6d and 9a with each other, the rotational movement of the gear 1 is smoothly transmitted to the rotary shaft 13. It is transmitted to the connected connecting member. The cylinder 6b of the armature hub 6 and the cylinder 9 of the clutch body 8 used in one embodiment of the electromagnetic clutch of the present invention can be manufactured by molding with synthetic resin or the like, so that sliding with the yoke is smooth. To be done. According to the electromagnetic clutch of the present invention, since the torque is transmitted by meshing as the electromagnetic clutch, the size and weight can be reduced. Further, since the elastic force of the elastic member can be weakened, the response time of the electromagnetic clutch can be shortened. Moreover, the armature and the gear can be integrally configured with a simple configuration, and the manufacturing is simple. Moreover, by molding with a synthetic resin, the weight can be reduced, the number of parts can be reduced, and an electromagnetic clutch with good rotation efficiency can be provided. With the above-described configuration, the manufacturing is simplified and the manufacturing cost can be reduced. Moreover,
Since the fixed frame is integrally formed by deep drawing, it is possible to prevent leakage of magnetic force of the electromagnet, and it is possible to provide a high-performance electromagnetic clutch.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side view of a drive gear of an embodiment of an electromagnetic clutch of the present invention. FIG. 2 is an armature drawing of an embodiment used in the electromagnetic clutch of the present invention, (A) is a left side view, (B) is a sectional view, (C) is a plan view, and (D) is a right side view. is there. FIG. 3 is a sectional view of an embodiment of the electromagnetic clutch of the present invention. FIG. 4A is a left side view of FIG. (B) is FIG.
Is a right side view of [reference numeral] 1 ... Gear 2 ... Fitting hole 3 ... Shaft hole 5 ... Elastic member 6 ... Armature hub 6a ... Guide leg 7 ... Armature 8 ... Clutch body 9 ... Cylindrical body 9a ... Engagement Tooth claw 10 ... Bearing 11 ... Electromagnet 12 ... Fixed frame 13 ... Rotating shaft 14 ... Lead wire

Claims (1)

Claim: What is claimed is: 1. A gear or pulley provided with a plurality of oval fitting holes on a concentric circle, and a groove for fixing an elastic member for urging the armature hub, and the gear or pulley. A plurality of guide legs that are loosely fitted in the fitting holes of the pulley are extended, a plurality of engaging tooth claws are projected on the opposite surface, and a recess for locking the tip of the elastic member is formed on the gear wheel or pulley side of the cylindrical portion. Armature attracted by an electromagnet and an electromagnet formed by winding a winding coil are arranged in a fixed frame on the outer periphery, and a plurality of engaging claws that engage with the engaging claws of the armature hub are projected. And a clutch main body in which a bearing is connected to the cylinder, and by energizing the electromagnet, the armature facing the electromagnet is attracted to resist the biasing force of the elastic member of the gear or pulley. The guide leg of the armature hub is slid in the fitting hole of the gear or the pulley to move the armature hub, and the engaging tooth claw of the armature hub and the engaging tooth claw facing the clutch body are engaged. An electromagnetic clutch that is characterized by transmitting rotary motion. 2. The electromagnetic clutch according to claim 1, wherein the gear or pulley, the armature having an engaging tooth claw, the cylinder of the clutch body, and the bearing of the clutch body are molded of synthetic resin. . 3. The electromagnet of the clutch body is fixed,
A synthetic resin bearing is fixed in the drawn metal fixing frame shaft hole, and the cylindrical body is rotatably fitted and the guide leg of the armature hub is loosely fitted in the fitting hole of the gear or pulley. The tip of the elastic member is engaged with the recess of the armature hub.
And the electromagnetic clutch described in 2. 5. A guide leg of the armature hub is loosely fitted in the fitting hole of the gear or pulley, the tip of the elastic member is engaged with the recess of the armature hub, and the electromagnet is fixed to the metal. The bearing made of synthetic resin is fixed in the shaft hole of the fixed frame of the above, and the cylinder having the engaging tooth claw is rotatably fitted, and the cylinder of the armature hub is slidably fitted into this cylinder. 3. The electromagnetic clutch according to claim 1, wherein the electromagnetic clutch is coaxially arranged.