JPH0122981Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a so-called electromagnetic spring clutch that uses a coil spring for torque transmission and braking to prevent overrun of an output rotating member.

As is well known, electromagnetic spring clutches that utilize the tightening force of a coil spring to transmit torque from an input rotating member to an output rotating member have been widely used in power transmission systems of various types of equipment in recent years.

By the way, in this type of electromagnetic spring clutch, when the input rotation speed is reduced from the state in which torque is transmitted from the input rotation member to the output rotation member by tightening the coiled clutch spring, the output rotation member is transmitted due to inertia. may precede the rotation of the input rotating member. Further, when a heavy object is suspended by a hoisting machine or a hanging machine, the output rotating member receiving a load may rotate before the input rotating member.

This rotation of the output rotating member in advance of the rotation of the input rotating member, ie, the overrun phenomenon in which the output rotating member rotates in advance due to inertia, is dangerous for some devices and must be avoided.

Particularly in heavy lifting equipment, etc., it is necessary to prevent the load side from rotating rapidly due to the suspended load.

Therefore, clutches used in this type of equipment must be equipped with a braking mechanism to prevent overruns. Conventionally, as a braking mechanism to prevent overruns, a forced locking method using an attached solenoid or a friction method against the output rotating member has been used. Methods such as a plate pressure welding method or a method in which an electromagnet supported on the fixed member side is magnetically attracted to a disk fixed to the output rotating member have been adopted, but both of these methods significantly increase the volume of the electromagnetic spring clutch. cause

Based on the above-mentioned viewpoints, this invention provides an electromagnetic spring clutch that has an overrun prevention function and can be miniaturized with a uniaxial structure. One end of the coiled clutch spring, which has a diameter-reducing habit that can be freely tightened to the boss portion of the input rotating member, is placed on the side of the output rotating member, and
The other end is hooked to a sleeve that is supported concentrically with respect to the input rotating member and the output rotating member, while the proximal end is swingably supported on the field core side, and the base end is supported swingably in the direction of the end surface of the sleeve. The armature is provided with an armature capable of elastic tilting, the armature and the sleeve are relatively connectable, and the input rotating member and the output rotating member are provided with annular grooves having the same diameter and adjacent to each other. It is characterized in that a coil-shaped overrun prevention spring with a diameter-expanding tendency is incorporated over the inner circumferential surfaces of both annular grooves.

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

An embodiment of the electromagnetic spring clutch of this invention is shown in FIG. 1 in a sectional view taken along the line shown in FIG. 2, and in FIG. 2 in a front view. As shown in the drawings, the electromagnetic spring clutch of this invention has an output shaft 1 serving as an output rotating member as a tube shaft, which is connected to an input shaft (not shown) of a device so as to rotate integrally therewith.

An output boss 2 is fitted onto the output shaft 1 at an intermediate portion in the axial direction, and is fixed integrally by means such as welding.

Furthermore, an input hub 3 as an input rotating member is concentrically supported on the output shaft 1 so as to freely rotate freely, and the input hub 3 is equipped with a transmission member, such as a groove pulley or a gear A screw hole 4 for fixing a screw (none of which is shown) is provided at a predetermined position, and the screw hole 4 is supported by a snap spring 5 to prevent it from coming off.

On the other hand, the output shaft 1 is inserted into the center hole 8 of the inner pole 7 of the field core 6, which becomes a fixed member when attached to a device, so as to be freely rotatable.

The field core 6 includes the inner pole 7, an outer pole 9 integrally fixed to the inner pole, a bobbin 10 fitted and fixed to the inner pole, and an electromagnetic coil 11 wound around the bobbin 10.
Consists of etc.

The outer pole 9 is made of a single steel plate, as shown in FIG. 3, a cross-sectional view taken along the line in FIG. 4, a front view in FIG. 4, and a plan view in FIG. It is a pressed product and has horizontal parts 9A and 9B parallel to each other at the upper and lower parts, a vertical part 9c connecting these horizontal parts, and a hanging wall part 9D bent downward from the tip of the lower horizontal part 9B. The vertical portion 9C is provided with a hole 12 into which the end of the boss portion 7A of the inner pole 7 is fitted, while ear-like protrusions 13, 13 used for attachment to equipment are formed on both left and right sides. It has been done.

Screw holes 14, 14 are provided at symmetrical positions offset to the left and right sides of the hanging wall portion 9D of the outer pole 9, respectively.

As shown in FIGS. 1 and 2, metal bushes 15 are fixed to the screw holes 14 and 14 by screws 16 and spring washers 17, respectively.

The bushes 15, 15 are connected to the armature 18.
is supported so that it can be tilted freely.

The armature 18 is shown in FIG. 6 in a cross-sectional view taken from FIG. 7, and in a front view in FIG.
As shown in the plan view in FIG. 8, holes 19, 19 are provided at predetermined positions near the lower end to loosely fit into the bushes 15, 15, and a large hole 20 is provided near the center. Furthermore, a cut-out protrusion 21 is provided at the left and right center position of the upper end.

On the other hand, a predetermined annular shape is formed between the outer circumferential surface of the boss portion 2A of the output boss 2 which is the output rotating member, the outer circumferential surface of the boss portion 3A of the input hub 3 which is the input rotating member, and the inner circumferential surface 22a of the sleeve 22. A void S is formed.

The annular gap S is formed by supporting the sleeve 22 concentrically and rotatably on the flange portion 2B of the output boss 2 and the flange portion 3B of the input hub 3, and has a diameter-reducing habit. This is a space for storing a coiled clutch spring 23.

The sleeve 22 is shown in FIG. 9 as a cross-sectional view taken along the line of FIG. 10, as shown in FIG. As shown in FIG. 12 in the line view of FIG. 9, it has a flange portion 22A;
Recesses 24, 24 are provided at diametrically symmetrical positions on the surface facing the field core 6.

The recesses 24, 24 are radial grooves, one side of which is continuous with the inclined surface 24a, and when the armature 18 is pushed by the compression spring 25 and tilted,
The protrusion 21 of the armature 18 is slid into and engaged with the protrusion 21 of the armature 18.

The compression spring 25 has its base supported by spring receivers 26, 26 (only one shown) provided at left-right symmetrical positions on the upper part of the bobbin 10, and has its tip end abutted against predetermined positions on the left and right sides of the upper part of the armature 18,
The armature 18 is always given the tendency to tilt in the direction of the sleeve 22.

On the other hand, the clutch spring 23 is formed into a bent portion 23A with one end bent in the axial direction and a bent portion 23B with the other end bent outward in the radial direction.

The output boss 2 is shown in FIG. 13 as a cross-sectional view along the line in FIG.
As shown in a line sectional view, and as shown in FIG. 15 and a plan view taken in the direction of arrows in FIG. One bent portion 23A of the clutch spring 23 is hooked into a notch 27A.

The clutch spring 23 is connected to the other bent portion 23B.
is hooked to a notch 28 formed on the end surface of the sleeve 22 near the input hub 3, and is attached with a diameter-reducing habit, so if the sleeve 22 is free, the input hub 3 It has the function of tightening the outer peripheral surface of the boss portion 3A and rotating the input hub 3, output boss 2, and sleeve 22 together, but when the sleeve 22 is unable to rotate, the input hub 3 cannot be rotated in a predetermined direction. The winding direction is defined as the direction in which the winding loosens due to rotation.

In this embodiment, the armature 18 is supported by a loose fit between the bush 15 and the hole 19, and the compression spring 25 provides a tilting behavior in which the upper end, which is the free end, approaches the sleeve 22. may be connected to the field core 6 by a hinge, for example.

Further, the tilting behavior may be provided not by a compression spring but by a leaf spring or a tension spring, or by using fluid pressure.

The input hub 3 is connected by the clutch spring 23.
The electromagnetic spring clutch of this invention is capable of transmitting torque to the output shaft 1, which is an output rotating member, by tightening the boss portion 3A of the armature 18.
The clutch spring 23 can be tightened around the input hub 3 by magnetically attracting the input hub 3, but the output boss 2 integrated with the output shaft 1 and the input hub 3 are also used as a braking mechanism to prevent overrun. Overrun prevention spring 29 that can be freely pressed against
It has built-in.

The overrun prevention spring 29 is a coil spring with a tendency to expand in diameter, and has an outer diameter formed on the inner peripheral surface of mutually continuous annular grooves 30 and 31 formed in the boss portion of the output boss 2 and the boss portion 3A of the input hub 3. The surfaces are pressed against each other, but the winding direction is the same as that of the clutch spring 2.
It is set in the same direction as 3.

On the other hand, a stopper pin 32 implanted in the sleeve 22 is inserted into the notch 27B of the output boss 2.

The correlation between the stopper pin 32 and the notch 27B is such that the thickness of the stopper pin 32 and the width of the notch 27B in the circumferential direction do not prevent the clutch spring 23 from tightening around the boss portion 3A of the input hub 3, and The clutch spring 23 is designed so that its outer diameter surface does not come into contact with the inner peripheral surface 22a of the sleeve 22 when the clutch spring 23 is expanded in diameter.

When the electromagnetic spring clutch of this invention configured as described above is in the state shown in FIG.
Even if the input hub 3 rotates, the sleeve 22 is prevented from rotating by the armature 18, so the clutch spring 23 does not rotate.

If the clutch spring 23 does not rotate, the output boss 2 will not rotate. The rotating shaft 1 to which the output boss 2 is fixed integrally is kept in a stopped state despite the rotation of the input hub 3.

The input hub 3 that is rotating at this time has a rotation direction opposite to the winding direction of the clutch spring 23, which has a tendency to tighten, so that there is no friction between the input hub 3 and the clutch spring 23 that causes large wear. No contact relationship.

On the other hand, if the output shaft 1 tries to over-rotate (overrun) due to inertia despite the stoppage of the sleeve 22, or the input rotational speed decreases and the output rotating member moves faster than the input rotating member due to inertia. The overrun prevention spring is used when the load on the output side is falling faster than the input rotating member due to a large hanging load such as a hoisting machine, hoisting machine, or other heavy lifting machine. Overrun of the output shaft 1 is reliably prevented by the frictional contact force exerted by the input hub 3 and the output boss 2 integral with the output shaft 1.

As is clear from the above description, the electromagnetic spring clutch of this invention has many excellent advantages, such as being able to reliably prevent overrun of the output rotating member, having a uniaxial structure, and being able to be miniaturized.

[Brief explanation of the drawing]

Fig. 1 is a sectional view taken along the - line in Fig. 2 showing an embodiment of the electromagnetic spring clutch of this invention, Fig. 2 is a front view, Figs. 3 to 5 show the outer pole of the field core, and The figure is Figure 4 - Linear sectional view,
FIG. 4 is a front view, and FIG. 5 is a plan view. Figures 6 to 8 show the armature, and Figure 6 shows the armature.
FIG. 7 is a front view, and FIG. 8 is a plan view. 9 to 12 show the sleeve, FIG. 9 is a sectional view of FIG. 10, and the first
0 is a view in the direction of the arrows in FIG. 9, FIG. 11 is a view in the direction of the XI arrows, and FIG. 12 is a view in the direction of the XII arrows. Figures 13 to 15 show the output boss, and Figure 13 shows the output boss.
14 is a sectional view taken along the line in FIG. 13, and FIG. 15 is a sectional view taken along the line in FIG. In the drawings, 1...output shaft, 2...output boss, 2A...boss part, 2B...flange part, 3...
...Input hub, 3A...Boss part, 3B...Flange part, 6...Field core, 7...Inner pole, 9...
Outer pole, 10... Bobbin, 11... Electromagnetic coil, 1
4...screw hole, 15...button, 16...screw, 18...armature, 19...blind hole, 2
DESCRIPTION OF SYMBOLS 1...Protrusion, 22...Sleeve, 22a...Inner peripheral surface, 22A...Flange part, 23...Clutch spring, 23A, 23B...Bending part, 24...
Recessed portion, 25... Compression spring, 27A, 27B, 28
... Notch, 29 ... Overrun prevention spring,
30, 31... annular groove, 32... stopper pin.

Claims (1)

[Scope of utility model registration request] The output rotating member, the input rotating member, and the field core are arranged on the same axis, and one end of a coiled clutch spring with a diameter-reducing habit that can be freely tightened to the boss of the input rotating member is placed on the output rotating member side. ,
Further, the other end is hooked to a sleeve that is supported concentrically with respect to the input rotating member and the output rotating member, while the proximal end is swingably supported on the field core side, and the end surface of the sleeve is The armature is provided with an armature that can be elastically tilted in a direction, the armature and the sleeve are relatively connectable, and the input rotating member and the output rotating member are provided with annular grooves having the same diameter and adjacent to each other. An electromagnetic spring clutch is formed by incorporating a coil-shaped overrun prevention spring with a diameter-expanding tendency over the inner peripheral surfaces of both annular grooves.