JPH0242896Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is used in electromagnetic armature actuating devices such as electromagnetic clutches and electromagnetic brakes to constantly adjust the gap between the armature and the adsorption surface of a rotor, etc., to a constant level when the armature is released. The present invention relates to an automatic air gap adjustment device for.

[Conventional technology]

When the armature of the electromagnetic clutch/brake is released, the gap between the armature and the armature suction surface must always be maintained at a constant value, and the armature suction time due to coil excitation must be kept constant. This is because as the number of times the electromagnetic clutch/brake engages and brakes increases, the friction surface wears out and the gap widens.The armature suction time due to coil excitation becomes longer, slowing down the engagement/braking operation, and furthermore, the gap widens. This is because if the coil is energized, the attraction force will not be applied to the armature, resulting in a failure in which connection and braking will not occur, so it is necessary to prevent this.

Conventionally, devices disclosed in Japanese Utility Model Publications No. 58-13143 and Japanese Utility Model Publication No. 59-5234 are known as devices that prevent the occurrence of such defects and automatically adjust voids. These devices utilize the frictional force between the bush and the member holding the armature to prevent the leaf spring holding the armature from returning.

[Problem that the invention attempts to solve]

Therefore, when the leaf spring holding the armature is pulled out in the direction of the armature suction surface by the excitation force of the coil, the frictional force acts largely.

As a result, the amateur's responsiveness deteriorated, and the coil required a large current, resulting in increased power consumption.

The present invention aims to eliminate the above defects.

[Means to solve problems]

In order to achieve the above object, the present invention provides that when the gap between the armature 21 and the armature suction surface 8a is larger than a predetermined size, when the armature 21 is attracted to the armature suction surface 8a, the shaft body 18 for adjusting the gap is moved. In the apparatus in which the armature is moved in the direction of the armature suction surface 8a by the increase in the gap, a predetermined gap G is provided on the armature attraction surface 8a.
1 and the armatures 21 facing each other, the armatures 21 are fixed to a first leaf spring 17, and a second leaf spring having a larger return elasticity than the first leaf spring 17 is attached to the first leaf spring 17. 14 is fixed, the second plate spring 14 is fixed at a proper position of the armature holder 12, and the shaft body 1 is fixed in order to move in conjunction with the movement of the shaft body 18.
8 is engaged with the second leaf spring 14, and a leaf spring 14 and the armature holder 12 are formed between the second leaf spring 14 and the armature holder 12 by the deflection of the leaf spring 14. An elastic body 28 is arranged so as to be biased in the direction of entering the gap between the two.

[Effect]

In the above configuration, when the gap between the armature 21 and the attraction surface 8a increases, when the armature 21 is attracted to the attraction surface 8a by magnetic force, the shaft body 1
8 bends the second leaf spring 14 to
4 and moves in the direction of the suction surface 8a by the amount of increase in the gap. At this time, the second leaf spring 14
It is formed by the deflection of The second leaf spring 1
An elastic body 28 enters the gap between the armature holder 12 and the armature holder 12, and holds the second leaf spring 14 in a bent state. When the magnetic force acting on the attracting surface is eliminated, the armature 21 is separated from the attracting surface 8a by the first leaf spring 17 and returns to its original position with respect to the shaft body 18. At this time, the second leaf spring 14 is
Since the curved state is maintained due to the increase in the gap,
The armature 21 faces the suction surface 8a with an initially set gap G1, and the increase in the gap is automatically corrected.

〔Example〕

The configuration of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

In FIG. 1, 2 is a stator of an electromagnetic clutch 4, which has a built-in coil 6. 8 is a rotor, and an amateur suction surface 8a made of a lining is formed on the rotor.

10 is a hub, and a plate-shaped armature holder 12 is fixed to this. Reference numeral 14 denotes a ring-shaped leaf spring, which is fixed to the armature holder 12 by a rivet 16. 17 is
It is a ring-shaped leaf spring and is fixed to the armature 21 with a rivet 19. Reference numeral 18 denotes a shaft body with a thread cut on its outer circumferential portion, which is loosely fitted into a hole provided in the holder 12, and into which the holes provided in the leaf springs 17 and 14 are fitted. .
The leaf spring 17 is crimped and fixed to the head of the shaft body 18 by a tube body 20 that is screwed onto the shaft body 18, and the leaf spring 14
is a tube body 22 that is screwed into the tube body 20 and the shaft body 18;
It is fixed to the shaft body 18 by the clamping pressure between the two. The head 18a of the shaft body 18 is loosely fitted into a stepped hole 26 transparently provided in the armature 21, and one side of the flange 18b formed on the head 18a is connected to the large diameter portion of the hole 26. is facing the bottom of the

Reference numeral 28 denotes an elastic body having an annular portion 28a fitted into the outer peripheral surface of the tubular body 22, and the elastic body 28 is inserted between the leaf spring 14 and the holder 12. The elastic body 28 has linear portions 2 in the direction of both ends.
8b, 28c are formed, and the linear portions 28b, 2
The original shape of 8c is formed in a straight line with both ends separated.

The original shape retaining force of the leaf spring 14 is set to be larger than the original shape retaining force of the leaf spring 17 within a predetermined range, and the attractive force of the attraction surface 8a to the armature 21 due to the excitation force of the coil 6 is It is set considerably larger than the original shape holding force of the spring 14.

Next, the operation of this embodiment will be explained.

Before the amateur suction surface 8a wears out, first,
The linear parts 28b and 28c of the elastic body 28 are connected to the elastic body 2.
8, and bend them so that they are substantially parallel to each other. In this state, the armature 21 and the armature suction surface 8a are at a predetermined gap G1.
and the back surface of the flange 18b of the shaft body 18,
The bottom surface of the large diameter portion of the hole 26 faces the gap G2, which is the same as the gap G1 described above. coil 6
When a current flows through the rotor 8, a magnetic flux is generated on the armature attraction surface 8a of the rotor 8, and the armature 21 is brought into close contact with the attraction surface 8a of the rotor 8 due to the magnetic force, and the rotor 8
The side and the hub 10 side are connected. When the armature 21 is attracted to the attraction surface 8a, if there is no wear on the attraction surface 8a, only the armature 21 moves in the direction of the rotor 8 due to the deflection of the leaf spring 17, and the shaft body 18 is attached to the armature holder 12. Don't move against it. However, when wear occurs between the armature 21 and the suction surface 8a, the gap between them becomes G1.
+α (amount of wear) and the initially set gap G1
Become bigger. Therefore, in this state amateur 2
1 is magnetically attracted to the attraction surface 8a, the bottom surface of the large diameter portion of the stepped hole 26 of the armature 21
collides with the back surface of the flange portion 18b, and pulls out the shaft body 18 against the elasticity of the leaf spring 14 by the amount of wear α toward the suction surface 8a. With this movement of the shaft body 18, the fixed part of the leaf spring 14 to the shaft body 18 becomes attached to the suction surface 8.
It curves protrudingly in the a direction. Due to the bending of the leaf spring 14, the straight portions 28a, 28 of the elastic body 28
b is displaced in the direction of expansion due to their elasticity,
Due to the bending of the leaf spring 4, it enters the gap formed between the leaf spring 14 and the armature holder 12.
Therefore, even if the coil 6 is de-energized and the armature 21 is separated from the suction surface 8a due to the elasticity of the leaf spring 17, the bent state of the leaf spring 14 is maintained by the linear portion 18b of the elastic body 18, The shaft body 18 is held by the wedge action of the armature holder 1 without being pulled back to the armature holder 12 side.
Maintain the state protruding from 2. Therefore, when the armature 21 is returned by the leaf spring 17,
The wear amount α is corrected, and for the suction surface 8a,
They face each other with the initially set gap G1.

Incidentally, when implementing the present invention, the leaf spring 14 may be constituted by a plurality of leaf springs, and the shape of the elastic body 28 is not particularly limited to that shown in the drawings. FIGS. 4 and 5 show an embodiment using a coil-shaped elastic body 30 that tends to expand in the direction of diameter expansion. Further, as shown in FIGS. 6 and 7, one ring-shaped elastic body 32 is arranged around the entire circumference of the leaf spring 14, and the diameter expansion elasticity of the elastic body 32 is used to expand the leaf spring 14. It may be configured to prevent return displacement. Further, as shown in FIG. 8, a tapered surface 12a is formed on the armature holder 12, and a ring-shaped elastic body 34 is arranged on this tapered surface 12a, and the diameter reduction elasticity of this elastic body 34 is used to tighten the plate. It may be configured to prevent the spring 14 from returning to its original position. In FIG. 8, when the armature 21 is attracted to the attraction surface 8a in a state where the gap between the armature 21 and the attraction surface 8a has expanded beyond a predetermined gap, the flange portion 18b fixed to the shaft body 18 is Spring 1
4 and moves toward the suction surface 8a, at this time, the leaf spring 14 is bent, and the elastic body 34 is configured to bite into this bent position. In the figure, a leaf spring 17 is fixed to an armature 21 via a shaft 18, and the leaf spring 17 is fixed to a leaf spring 14 with screws 40. The leaf spring 14 is fixed to the armature holder 12 with bolts 42.

〔effect〕

In this invention, as mentioned above, when the leaf spring that holds the armature moves toward the armature suction surface, the elastic body does not act as a large frictional force, so the responsiveness of the armature is not impaired, and the power consumption of the coil is reduced. This has the effect of saving money.

[Brief explanation of drawings]

The drawings show a preferred embodiment of the present invention; FIG. 1 is a sectional view, FIG. 2 is a sectional view, FIG. 3 is a side view, FIG. The figure is the same, a side view, FIG. 6 is an explanatory diagram showing another embodiment,
FIG. 7 is an explanatory view of the same, FIG. 8 is a sectional view showing another embodiment, FIG. 9 is a side view of the same, and FIG. 10 is a sectional view of the same. 2... Stator, 4... Electromagnetic clutch, 6...
Coil, 8...Rotor, 8a...Adsorption surface, 10...
...Hub, 12...Amachi your holder, 14...
Leaf spring, 16... Rivet, 17... Leaf spring, 1
8... Shaft, 18b... Flange, 19... Rivet, 20, 21... Tube, 26... Stepped hole, 2
8...Elastic body, 30, 32... Elastic body.

Claims (1)

[Scope of utility model registration request] Amateur 21 against the Amateur suction surface 8a
When the gap is larger than a predetermined size,
In a device in which when the armature 21 is attracted to the armature suction surface 8a, the shaft body 18 for gap adjustment moves in the direction of the armature attraction surface 8a by the increase in the gap, a predetermined gap G1 is created on the armature attraction surface 8a. The armature 21 is fixed to the first leaf spring 17 , and the armature 21 is fixed to the first leaf spring 17 .
A second leaf spring 14 having a larger return elasticity is fixed, and the second leaf spring 14 is attached to the amateur holder 1.
2, and engages the second leaf spring 14 with the shaft body 18 in order to move in conjunction with the movement of the shaft body 18, and between the second leaf spring 14 and the armature holder 12. The plate spring 14 and the armature holder 1 formed by the deflection of the plate spring 14
The elastic body 2 is biased in the direction of entering the gap between the two.
8. An automatic air gap adjustment device in an electromagnetic armature actuating device, characterized in that: