JPH0527706Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electromagnetic coupling device widely used in various devices such as OA equipment and FA equipment, and particularly relates to structural improvement of the yoke thereof.

[Prior art] Conventionally, as this type of electromagnetic coupling device, for example, the fourth
As shown in the cross-sectional view in the figure, numeral 1 is an electromagnetic coupling device, which is installed in a space surrounded by a frame 3 of an OA device 2 and a cup-shaped frame 4 attached to the frame 3. Reference numeral 5 denotes a yoke integrally formed with a U-shaped cross section, which is supported on the rotating shaft 7 via a bearing 6 on the inner periphery of its inner cylindrical portion so as to be rotatable relative to this shaft, and is In order to prevent twisting, it is fixed to the frame 3 with a stop pin 8. The rotating shaft 7 is supported by the frames 3 and 4 via bearings 9 and 10 at both ends. Reference numeral 11 denotes an electromagnetic coil which is housed in the recess of the yoke 5. Reference numeral 12 is a rotor having a knurling formed on the rotary shaft 7 and fitted onto this part, and magnetic poles are formed inwardly and outwardly with a non-magnetic material 13 interposed therebetween. An armature 14 faces the magnetic pole portion of the rotor 12 with a gap in between, and is attached to the inner surface of the gear 16 via a leaf spring 15. gear 1
6 is rotatably supported at one end on the rotating shaft 7,
A gear 17 is fitted to the other end of the rotating shaft 7 using a pin 18 so as to rotate together with the rotating shaft,
A gear (not shown) of the OA equipment 2 meshes with this gear 17 either directly or via a timing belt or the like.

To explain the operation of the above-mentioned conventional electromagnetic coupling device, the gear 16 meshes with a drive motor pinion (not shown) and is driven to rotate, and when the electromagnetic coil 11 is energized, the armature 14 is attracted to the rotor 12 by its electromagnetic attraction force. therefore, the rotor 1
2. The shaft 7 and the gear 17 rotate together with the gear 16, and the gear of the OA equipment that meshes with the gear 17 is rotationally driven.

[Problems to be solved by the invention] By the way, in the conventional electromagnetic coupling device described above, in order to integrally form the yoke 5 with a U-shaped cross section, it is manufactured by casting and cutting, or by press-drawing a plate material. Furthermore, the bearings 6 and 9 must be fitted separately to the inner periphery of the yoke 5, resulting in complicated manufacturing and increased costs.

The present invention was made to solve such problems, and an object of the present invention is to provide an electromagnetic coupling device that is easy to manufacture and can be manufactured at low cost.

[Means for Solving the Problems] The present invention uses a part of the frame that supports the rotating shaft of the electromagnetic coupling device as a yoke member, and uses this part as a separate inner yoke member and outer yoke member, respectively. A yoke having a U-shaped cross section is formed by joining the inner yoke members, and the inner yoke member is molded from an oil-impregnated sintered alloy so that it also serves as a bearing.

[Function] The frame and the outer yoke, which are part of the yoke, can be easily fabricated from plate materials, and the inner yoke can be easily fabricated by molding an oil-impregnated sintered alloy that also serves as a bearing.

[Example] Examples of the electromagnetic coupling device according to the present invention are shown in Figs.
This will be explained with reference to FIG. Components that are the same as those of the conventional example shown in FIG. 4 are given the same reference numerals and their explanations will be omitted.

In this embodiment, the yoke 23 has a cylindrical inner yoke member 24 molded from an iron-based oil-impregnated sintered alloy, and a cylindrical outer yoke member 25 concentric with the inner yoke member 24, which is formed by rolling a plate material into an annular shape. formed,
One end of each of the inner yoke member and the outer yoke member is coupled to a coupling portion 26 that is a part of the frame 3 to form a yoke having a U-shaped cross section.

The inner yoke member 24 also serves as a bearing, and one end has a small-diameter portion 24a with a part of its periphery cut out.This joint portion is press-fitted into a corresponding hole formed in the joint portion 26 of the frame 3. The rotating shaft 7 is supported on the inner circumferential surface. Furthermore, the outer yoke member 25 is formed into an annular shape as shown in FIG. 26 into the holes corresponding to the protrusions 25a, and the ends of each protrusion are crushed to be fixed to the frame. In other respects, the structure is similar to the conventional structure, such as the electromagnetic coil 11 being housed in the recess of the yoke having a U-shaped cross section.

In the electromagnetic coupling device according to the present invention having the above configuration, when the electromagnetic coil 11 is energized, the path shown by the broken line is the outer yoke member 25, the coupling portion 26 which is a part of the frame 3, the inner yoke member 24, the rotor 12, Magnetic flux flows through the armature 14, and the armature 14 is attracted to the rotor 12.

Therefore, the rotational force of the gear 16 that rotates while meshing with the drive motor pinion (not shown) is equal to the torque of the armature 1.
4. It is transmitted to the rotor 12, rotating shaft 7, and gear 17 via the leaf spring 15, and meshes with the gear 17.
The gears of the OA equipment 2 are rotationally driven.

[Effects of the invention] As described above, the electromagnetic coupling device of the present invention has an outer yoke member formed from a plate material, an inner yoke member which also serves as a bearing, and is molded from an iron-based oil-impregnated sintered alloy. The yoke is constructed by connecting one end of the inner yoke member to a part of the frame that supports the electromagnetic coupling device, and has the advantage of being simple and inexpensive to manufacture.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an electromagnetic coupling device according to the present invention. FIG. 2 is a perspective view of the outer yoke member. FIG. 3 is a side view of a portion of the frame, which is a connecting portion between an outer yoke member and an inner yoke member. FIG. 4 is a longitudinal sectional view of a conventional electromagnetic coupling device. 1 ... Electromagnetic coupling device, 3... Frame, 23 ...
... Yoke, 24 ... Inner yoke member, 25 ... Outer yoke member, 26 ... Yoke joint portion (part of frame 3).

Claims (1)

[Claims for Utility Model Registration] 1. An inner yoke member and an outer yoke member, which are separate bodies, are concentrically connected to a frame, and a portion of the frame sandwiched between the inner yoke member and the outer yoke member. An electromagnetic coupling device characterized in that the inner yoke member and the outer yoke member form a yoke having a U-shaped cross section. 2. The electromagnetic coupling device according to claim 1, wherein the inner yoke member is made of an iron-based oil-impregnated sintered alloy and also serves as a bearing.