JPH02275126A - Friction plate for electromagnetic brake - Google Patents

Abstract

PURPOSE:To obtain a high reliable friction plate in a low cost together therewith to reduce noise by providing a circular base plate having the central hole and other holes, and tabular rubber members joined to the surface and the back of the circular base plate and formed. CONSTITUTION:A circular sheet metal member 20 formed a spline hole 26 for the purpose of spline engagement with a hub in the center is provided with four slotted holes 24. Circular rubber layers are joined to the surface and the back of the circular sheet metal member 20 and formed while circular rubber layers on both surfaces are connected to each other in one body via four slotted holes 24 for forming tabular rubber members 22. In such way, it is possible to obtain a friction plate harmless for a human body, and, with high reliability in a low cost. Also, noise can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a friction plate used in a friction plate type electromagnetic brake. Therefore, it can be used for electromagnetic brakes for servo motors, etc.

[Conventional technology]

A friction plate type electromagnetic brake such as a servo motor is generally formed by a combination of cylindrical or polygonal tube-shaped members, and the friction plate is made of an annular plate member spline-engaged with a hub. When the armature operates, this friction plate is pressed against the end plate, which is a fixed member, and brakes the rotating shaft that is integrally attached to the hub, or it becomes free against the end plate and releases the rotating shaft. This serves to ensure the rotation of the rotating shaft. In addition, friction plates were generally molded from asbestos, but as asbestos is harmful to the human body, non-asbestos friction plates made of four annular metal plates with annular rubber plates glued to both sides have also been used. ing.

[Problem to be solved by the invention]

However, when molded with asbestos, the asbestos has relatively low wear resistance, and continuous use may cause the thickness of the friction plate to decrease or the fibers on the friction surface to become clogged, resulting in It cannot be said that its reliability is high, as the coefficient of friction is small. Furthermore, the formability is not good, and the dimensional accuracy of the spline part that engages with the hub is insufficient, and if the fit between the two is too tight, the spline of the asbestos friction plate will not work even after the brake is released. The spline part gets caught on the hub and therefore cannot be completely freed from the end plate which is the fixed part, which can cause abnormal wear. Also, if the fit between the two parts is loose, so-called spline play will increase. As a result, the rotational play of the shaft member during braking operation increases.

Asbestos as a material is also more expensive than common rubbers and resins.

In a method in which a rubber plate is bonded to a metal plate, repeated loads and vibrations act on the friction plate, so there is a possibility that peeling may occur due to changes in the adhesive over time. In addition, since the hub and the spline portion of the friction plate that engages with the hub are made of metal,
Noise is generated when the brake starts to work and when it is released.

Therefore, in order to solve this problem, the first object of the present invention is to provide a low-cost and highly reliable friction plate.

A second object of the present invention is to provide a friction plate that does not generate noise when starting and releasing braking.

[Means to solve the problem]

In view of the above-mentioned first object, the present invention provides an annular substrate having a central hole and further having other holes, and an annular substrate that is bonded to the front and back surfaces of the annular substrate and that Provided is a friction plate for an electromagnetic brake characterized by comprising a plate-shaped rubber member integrally formed with each other.

In order to achieve the first and second objects, the present invention includes integrally bonding a resin member to the periphery of the central hole of the annular substrate, and forming the inner peripheral edge of the resin member into a spline shape. A friction plate for an electromagnetic brake is provided.

[For production]

The plate-shaped rubber members that generate frictional force are joined to the front and back surfaces of the annular substrate, and are integrally formed with each other through the other holes of the annular substrate, so that the plate-shaped rubber members It does not come off from the annular substrate.

Furthermore, when a resin member having a spline portion is integrally joined to the inner peripheral portion of the annular substrate, noise generated between the resin member and the metal hub is reduced.

〔Example〕

The present invention will be described in more detail below based on embodiments shown in the accompanying drawings. First, referring to FIGS. 8 and 9, the end plate 56 is separated from the core 50 by an appropriate dimension via a spacer 64, and is fixed by a screw member 62. A friction plate 58 and an armature 54 are arranged between the end plate 56 and the core 50. Armature 5
4 is configured to be movable along the spacer 64,
The friction plate 58 is splined to a hub 60 that can be fixed to a rotating shaft 66. A winding bundle 52 is housed in the core 50, and a coil spring (not shown) is also built in, so that when the winding bundle 52 is not energized, the coil spring is connected to the armature 54.
and the friction plate 58 are pressed against the end plate 56 to brake and fix the hub 60 and the rotating shaft 66, and when the winding bundle 52 is energized, the armature 54 is attracted toward the core 50 and the friction plate 58 is released. The hub 60 and the rotating shaft 66 become rotatable. Various configurations of the friction plate 58 will be explained below.

Referring to FIGS. 1 and 2, in this embodiment, four elongated holes 24 are provided in an annular sheet metal member 20 having a spline hole 26 formed in the center for spline engagement with the hub. be. The annular sheet metal member 20 has a thickness that allows punching, and the spline hole 26, the four elongated holes 24, and the outer periphery can be formed by one punching operation. The annular sheet metal member 20 thus formed is molded with a high-temperature melted rubber material, such as ethylene propylene rubber, to bond and form annular goto layers on the front and back surfaces, and four The annular rubber layers on both sides are integrally connected to each other via the elongated holes 24 to form the plate-shaped rubber member 22. With such a structure, the plate-shaped rubber member 22 becomes difficult to peel off or separate from the annular sheet metal member 20. Further, it is clear that the shape and number of the long holes 24 are not limited to those described above.

Referring now to FIGS. 2 and 3, only the inner circumference is different compared to the embodiment shown in FIG.

That is, the inner periphery 27 of the annular sheet metal member 20' is circular, and the inner periphery is covered with a resin material such as Rydon (trade name), and the spline portion 2 engages with the hub.
8 is formed. The method for forming this friction plate is as follows:
An annular sheet metal member 20 having two elongated holes 24 is prepared, and the spline portion 28 is formed by injecting the Rydon into the sheet metal member 20 by injection molding. Next, it is formed by molding propylene rubber. This is because the melting temperature of Rydon is 260°C, which is higher than the melting temperature of ethylene propylene rubber, 220°C, so Rydon is injection molded first and then propylene rubber is molded, but when using other materials, If the magnitude of the melting temperature is reversed, the order of molding will be reversed accordingly.

Since the spline portion 28 of the friction plate formed in this manner is made of a resin material, the noise is considerably reduced even though the engaging hub 60 (FIG. 8) is made of metal.

FIG. 5 differs from the embodiment shown in FIG. 3 only in that the inner peripheral edge 32 of the annular sheet metal member 20'' is not circular, but is formed into sawtooth-like irregularities.

The spline portion 28 made of resin material is connected to the hub 60 (FIG. 8).
When the hub 60 engages with the hub 60 and rotates with the hub 60, a force is applied in the circumferential direction. When this rotation is started or stopped, a force that causes the joint between the spline portion 28 and the annular sheet metal member 20'' to separate acts due to the inertial force of the entire friction plate.

The above-mentioned serrated inner peripheral edge 32 increases the resistance to the peeling force and serves to strengthen the fixation between the resin spline portion 28 and the annular sheet metal member 20''.The annular sheet metal member 20'' is punched, so that the above-mentioned The formation of the serrated inner peripheral edge 32 does not incur any particular cost increase.

In any of the embodiments shown in FIGS. 1 to 5,
The plate rubber member 22 is replaced with the annular sheet metal member 20, 20' or 2p.
Generally, the force that causes the plate-shaped rubber member 22 to peel off from the plate-shaped rubber member 22
Since it is largest at the outer periphery of the plate-shaped rubber member 22, it is recommended to provide an annular frame 34 (FIGS. 6 and 7) made of a resin material integrally bonded to the annular sheet metal member so as to contact the outer periphery of the plate-shaped rubber member 22. This is effective in preventing the rubber member 22 from peeling off. In contrast to the embodiment shown in FIG. 5, a friction plate having an annular flare 34 made of a resin material provided on its outer periphery is shown in FIGS. 6 and 7. The resin annular frame 3-4 can be molded at the same time as the resin spline portion 28 on the inner peripheral side is injection molded, so that the increase in manufacturing cost can be kept small. As this resin material, the above-mentioned Rydon is used, and when the above-mentioned propylene rubber is used as the rubber material of the plate-shaped rubber member 22, the resin material is first injection molded because of the difference in melting temperature. If the inner corner of the annular frame 34 at the time of molding is formed into a chamfered slope 36, the boundary between the two members 22 and 34 due to heat shrinkage during the molding of the plate-shaped rubber member 22 to be molded later. Peeling is less likely to occur. Note that since the frictional action of the friction plate is performed by the surface of the plate-shaped rubber member 22, the plate thickness dimension of the annular frame 34 is set smaller than the surface-to-surface dimension of the plate-shaped rubber member 22. The structure of the annular frame 34 is the same when provided in other embodiments shown in FIGS. 1 to 4.

In each of the above embodiments, the outer peripheral shape of the friction plate is circular, but it is clear that it may be polygonal.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, it is possible to provide a friction plate that is harmless to the human body and highly reliable at low cost. Further, noise is reduced when starting and releasing braking.

[Brief explanation of drawings]

FIG. 1 is a front view showing a first embodiment of a friction plate according to the present invention, FIG. 2 is a sectional view taken along the arrow line ■-H in FIG. 1, and FIG. A front view showing the embodiment; FIG. 4 is a sectional view taken along arrow line 1'V-1'V in FIG. 3;
FIG. 5 is a front view showing a third embodiment of a friction plate according to the present invention, FIG. 6 is a front view showing a fourth embodiment of a friction plate according to the present invention, and FIG. 7 is an arrow line in FIG. Figure 8 is a cross-sectional view of the friction plate type electromagnetic brake;
A sectional view taken along the arrow line ■-■ in the figure, and FIG. 9 is a front view of the friction plate type electromagnetic brake. 20, 20', 20''... annular sheet metal member, 22
...Plate rubber member, 24...Long hole, 28...Resin spline part, 34...Resin annular frame.

Claims (1)

[Scope of Claims] 1. An annular substrate having a central hole and further having other holes, which are joined to the front and back surfaces of the annular substrate and are integrally formed with each other via the other holes. A friction plate for an electromagnetic brake, characterized by comprising a plate-like rubber member. 2. The friction plate for an electromagnetic brake according to claim 1, wherein a resin member is integrally joined to a peripheral portion of the central hole of the annular substrate, and an inner peripheral edge portion of the resin member is formed in a spline shape. 3. The friction plate for an electromagnetic brake according to claim 1, wherein a peripheral edge of the central hole of the annular substrate is formed in an uneven shape. 4. The friction plate for an electromagnetic brake according to claim 1, further comprising a resin ring member bonded to the outer periphery of the annular substrate in contact with the outer periphery of the plate-shaped rubber member.