JPS6222670Y2 - - Google Patents

Description

[Detailed description of the invention] This invention uses a so-called electromagnetic spring that uses the tightening force of a coil spring that is tightened by magnetic attraction of an armature to an input rotating member to transmit torque from an input rotating member to an output rotating member. It's about clutches.

Conventional electromagnetic spring clutches of this type have a first
As an example is shown in a vertical side view in the figure, a rotor 1 as an input rotating member and a hub 2 as an output rotating member are supported on the same axis on the output shaft 3 of a prime mover, for example, a motor. . The rotor 1 has a boss portion 1A and a flange portion 1B, and is connected to the output shaft 3 by a key 4 so as to rotate together with the output shaft 3. On the other hand, the hub 2 is supported on the output shaft 3 via bearings 5, 5 so as to freely rotate, has a boss portion 2A having the same diameter or approximately the same diameter as the boss portion 1A of the rotor 1, and has an output gear 6. are fixed concentrically by a plurality of bolts 7.

A coil spring 8 is loosely fitted into the hubs 1A and 2A.

The coil spring 8 has a bent portion 8A with one end bent outward, and this bent portion 8A is hooked to a notch 10 of an armature 9 that can freely magnetically attract the flange portion 1B of the rotor 1. on the other hand,
There is a bent part 8B with the other end bent inward,
This bent portion 8B is hooked into a notch 11 formed in the hub 2.

Further, the coil spring 8 is housed in an annular case 12, and an annular field core 15 with a built-in electromagnetic coil 14 to which a mounting plate 13 is fixed is exposed on the back side of the flange portion 1B of the rotor 1. be.

In the conventional electromagnetic spring clutch having such a structure, when voltage is applied to the electromagnetic coil 14,
The armature 9 is magnetically attracted to the flange portion 1B of the rotor 1. At this time, the bent portion 8 is attached to the hub 2, which is an output rotating member, on which the output gear 6 is loaded.
The coil spring 8 holding B is tightened when the armature 9 begins to rotate together with the rotor 1, and the hub 2 starts rotating together with the rotor 1, resulting in a torque transmission state. When the voltage application to the electromagnetic coil 14 is stopped from this state, the armature 9 separates from the flange portion 1B of the rotor 1, and the coil spring 8 is loosened.
Although the torque transmission is briefly interrupted, the hub 2 as an output rotating member tries to continue idling due to inertia.

If the output rotation member is allowed to idle, the generation of idle rotation due to inertia will not be a problem, but in various ticket vending machines and other devices where the phase of the output side is restricted, the voltage to the electromagnetic coil 14 By discontinuing the application, the torque transmission is interrupted, and at the same time, the hub 2 as the output side rotating member is required to stop.

In order to meet this requirement, conventionally it was necessary to provide a separate electromagnetic brake.

However, if an electromagnetic brake is installed, the equipment will become larger and the cost will increase. Therefore, instead of installing an electromagnetic brake, an electromagnetic spring clutch can be used that can stop the output rotation member from spinning at the same time as stopping torque transmission. development has been desired.

This invention provides an electromagnetic spring clutch that meets the above-mentioned needs, and includes an input rotating member and an output rotating member arranged on the same axis, each having a boss portion having the same diameter or approximately the same diameter. One end of a coil spring that can freely tighten the boss portions of both rotating members is hooked to an armature that can freely magnetically attract an input rotating member, while the other end is hooked to an output rotating member, and , in an electromagnetic spring clutch in which the coil spring is housed in an annular case, a fixing member is fixed to the case, and the inner diameter of the coil spring surrounding portion of the case is smaller than the outer diameter of the coil spring in an unloaded state. It has a slightly smaller diameter,
The present invention is characterized in that the output rotating member can be freely braked by the case and the coil spring.

Next, the electromagnetic spring clutch of this invention will be explained by way of examples with reference to the drawings.

FIG. 2 shows a first embodiment of the electromagnetic spring clutch of this invention in a longitudinal sectional side view. As shown in the drawings, the electromagnetic spring clutch of this invention has an annular case 12' fixed to, for example, a fixing member 16 on the motor side, and the inner diameter of the coil spring surrounding part 12'A surrounding the coil spring 8 is fixed to the coil spring 8. By forming the outer diameter of the coil to be smaller than the outer diameter of the coil under no load, the coil spring 8 and the annular case 12'
This is an electromagnetic spring clutch that obtains braking force through frictional contact with the electromagnetic spring clutch, and the structure of other parts is the same as the conventional electromagnetic spring clutch shown in Fig. 1. The same reference numerals as used are used, and the previous explanation is used.

The inner peripheral surface of the coil spring surrounding portion 12'A of the annular case 12' is preferably coated with a material (for example, rubber) that can increase the frictional force.

In the electromagnetic spring clutch of this invention having the above-described structure, when the armature 9 is magnetically attracted to the flange portion 1B of the rotor 1 by applying a voltage to the electromagnetic coil 14 and the coil spring 8 is tightened, the armature 9 is pulled from the rotor 1 to the hub 2. It is similar to a conventional electromagnetic spring clutch in that torque is transmitted to the coil spring clutch, but when the voltage application to the electromagnetic coil 14 is stopped and the armature 9 is demagnetized and separated from the flange portion 1B of the rotor 1, the coil spring 8 instantly expands in diameter and comes into pressure contact with the inner peripheral surface of the annular case 12'.

Since the annular case 12' is fixed to the fixed member 16, the coil spring 8 pressed against the annular case 12' cannot rotate.
The hub 2 engaged by B cannot rotate and does not spin due to inertia.

In the second embodiment shown in a vertical side view in FIG. 3, the shape of the annular case 12'' is different from the annular case 12' in the first embodiment described above, and further,
Fixed member 17 such as equipment frame on output rotating member side
The coil spring surrounding part 1
It is the same as the first embodiment in that the braking force is obtained by pressing the coil spring 8 against the inner circumferential surface of the 2"A. In this embodiment, the hub 2 is attached to the shaft 18 of the output side device with a key. It is fixed using 19.

As is clear from the above explanation, the electromagnetic spring clutch of this invention has the excellent advantage of being able to reliably prevent the rotation of the output side rotation member due to inertia at the same time as the torque transmission is interrupted, without adding an electromagnetic brake or the like. have

[Brief explanation of the drawing]

FIG. 1 is a longitudinal side view showing an example of a conventional electromagnetic spring clutch, and FIG. 2 is a longitudinal side view showing a first embodiment of the electromagnetic spring clutch of this invention.
FIG. 3 is a longitudinal sectional side view showing the second embodiment. In the drawings, 1... Rotor, 2... Hub, 8... Coil spring, 8A, 8B... Bent portion, 9... Armature, 12, 12', 12''... Annular case, 1
2'A, 12''A...Coil spring surrounding part, 1
6, 17...Fixing member.

Claims (1)

[Scope of utility model registration request] An input rotary member and an output rotary member are arranged on the same axis, each having a boss portion having the same diameter or approximately the same diameter, and one end of a coil spring is configured such that the boss portions of both rotary members can be freely tightened. In an electromagnetic spring clutch, the coil spring is hooked to an armature that can freely magnetically attract an input rotating member, the other end is hooked to an output rotating member, and the coil spring is housed in an annular case. The case is fixed to a fixed member, and the inner diameter of the coil spring surrounding portion of the case is made slightly smaller than the outer diameter of the coil spring in an unloaded state, so that the output rotation member is braked by the case and the coil spring. An electromagnetic spring clutch that can be freely moved.