JPH0122493B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention automatically adjusts the gap between the armature of a friction transmission type electromagnetic clutch or brake and the transmission friction surface facing the armature to keep it constant at all times. Regarding mounting to hold the armature, in particular, the hub on the side that supports the armature is divided into two parts, inner and outer, and the connecting member fixed to one hub is press-fitted into the axial hole of the other hub. , suction of the armature by using the sliding friction force between the hub and the connecting member,
The present invention relates to an improvement in an automatic gap adjustment device that automatically corrects changes in the gap due to wear of the friction surface each time a release operation is performed.

[Prior art]

First, the case of an electromagnetic brake among conventional electromagnetic clutches and brakes of this type will be explained with reference to FIGS. 7 and 8. In the figure, reference numeral 1 denotes a yoke having an annular recess opening on one side, and each opening end serves as a magnetic pole part. 2 is a coil stored in the recess of the yoke 1, which together with the yoke 1 constitutes an electromagnet part, and this electromagnet part is fixed in a suitable position on the machine (not shown) in the yoke part when using the brake. and does not rotate. 3 is a friction plate provided to close the opening of the yoke 1, and 4 faces the magnetic pole portion connected to the yoke 1 on one side and the friction plate 3 with a gap g ₁ between them. The armature is fixed to the annular leaf spring 5 by rivets 6 at three equally spaced positions on its circumference. The leaf spring 5 is fixed to one side of the outer hub 8 at three locations on the circumference corresponding to intermediate positions of each rivet 6 by locking members 7 which also serve as bolts. The head of the locking member 7 faces a hole passing through the armature 4 in the axial direction, and a part of the head becomes a flange 9, and the inner surface of the flange forms a hole in the armature 4. The above-mentioned gap g ₁ is formed on the side surface of the protruding locking part 10.
They are facing each other with a distance of 〓g ₂ between them. The outer hub 8 is engaged with the inner hub 11 by splines 12 at its inner peripheral portion. Reference numeral 13 is a connecting member such as a spring pin, which is press-fitted across holes provided in the axial direction in both the inner and outer hubs 11 and 8, and is firmly connected to the outer hub 8 so that it cannot move relative to it. However, with respect to the inner hub 11, it can be slid in the axial direction within the hole under conditions described later. A plurality of connecting members 13 are provided on the same circumference at equal intervals. 14 is a braked shaft to which the inner hub 11 is fitted.

A conventional electromagnetic brake is constructed as described above, and when no current is supplied to the coil 2, the armature 4 is separated from the magnetic pole part, and the braking force on the braked shaft 14 is released, but when current is supplied to the coil. A magnetic flux exits from one magnetic pole part, passes through the air gap g ₁ , the armature 4, and the air gap g ₁ in order and returns to the other magnetic pole part, and the armature 4 receives an electromagnetic attraction force, and the force of the leaf spring 5 for releasing the armature is generated. The magnetic pole part and the friction plate 3 are brought into pressure contact with each other, and braking is applied to the armature 4. Therefore, the leaf spring 5, the outer hub 8, Braking is applied to the mechanically connected braked shaft 14 via the inner hub 11.

Then, due to wear of the friction surface (braking surface), a gap g ₁
If the gap g ₁ and the gap g ₂ are set to be equal, when the gap g 1 and the gap g 2 are set to be equal, the locking portion 10 of the armature 4 will close to the flange portion 9 of the locking member 7 during the suction process of the armature 4.
When the armature 4 collides with the armature, a gap corresponding to the amount of wear on the friction surface exists between the armature 4 and the friction surface facing it. This frictional force, and therefore the holding force of the inner hub 11 against the connecting member 13, is set so as to exceed the contact frictional force of the press-fitted connecting member 13 against the hole, so that during the suction process of the armature that is subsequently sucked. The outer hub 8 is forcibly moved along with the connecting member 13 to follow the armature 4, and the connecting member 13 is pulled out of the press-fit hole of the inner hub 11 by an amount corresponding to the amount of wear on the friction surface. Since the return movement amount of the armature 4 when the brake is released is always constant and equal to the gap _g1 , the gap is eventually adjusted to the original gap length.

[Problems with conventional technology]

Through the above action, the gap _g1 can be automatically adjusted, but in the conventional system, both the inner and outer hubs 11,
Torque between the parts 8 and 8 is transmitted by the spline 12, and the connecting member 13 has the function of adjusting the gap _g1 by utilizing its elasticity, and also absorbs the backlash of the spline 12. In this case, the connecting member 13 is strained by the buckling of the spline portion, and therefore the contact friction force of this connecting member with the hole of the inner hub 11 changes, and the holding force against the connecting member 13 in this case, that is, the dynamic force is changed. The holding force is smaller than the static holding force when each part is stationary, and this dynamic holding force is due to the torque (braking force) due to relative slippage between the friction plate 3 and the armature 4 during braking. fluctuation of,
Alternatively, it may decrease further due to fluctuations in the load torque, or it may instantaneously become zero. When this contact friction force or holding force is extremely reduced or instantaneously becomes zero, the leaf spring 5 is in a bent state in the braking state, and a force is applied to the connecting member 13 via the outer hub 8. Since a force is acting in the direction of pulling out the inner hub 11 from the hole, this force causes the connecting member 13 to be pulled out gradually from the press-fit hole, so that the gap g ₁ gradually closes with each braking operation. This results in a situation where not only the air gap adjustment function is lost, but in the worst case, the brake release function is also lost.

The above explanation was about the electromagnetic brake, but in the case of an electromagnetic clutch, the yoke 1 side or the braked shaft 1
The only difference from the brake is that one of the parts 4 is connected to the drive side and the other to the driven side, but it is structurally and functionally the same as the brake, which solves the problem mentioned above. The point is immanent.

In addition, as a conventional example, the connecting member 13 is connected to the inner hub 11.
Although the case has been described in which the gap is automatically adjusted by sliding the connecting member 13 in the axial direction against the inner hub 11, the connecting member 13 is firmly press-fitted into the inner hub 11 so as not to be slidable, while the connecting member 13 is firmly press-fitted into the hole in the outer hub 8. On the other hand, press fitting is performed under the same conditions as those used for press fitting into the hole of the inner hub 11 in the above, that is, while maintaining the same contact friction force,
When adjusting the gap _g1 , the outer hub 8 is connected to the connecting member 1.
An electromagnetic brake or an electromagnetic clutch that is configured to move following the suction movement of the armature 4 while sliding on the armature 3 has the same problem as above, and furthermore, as shown in FIG. A gap g 2 equal to the gap g ₁ is created between the inner surface of the flange portion 9 of the locking member 7 and the outer surface of the outer hub 8, and when adjusting _{the gap g 1 ,} Even when the flange portion 9 of the locking member 7 is brought into contact with the outer hub 8 and the outer hub is moved to follow the armature 4, the same problem as above occurs.

[Purpose of the invention]

The present invention solves these problems and automatically adjusts the air gap in a normal manner at all times to ensure suction of the armature,
The purpose is to provide an electromagnetic clutch or brake with stable release characteristics.

[Structure of the invention]

In order to achieve the above object, the present invention includes a holding member and an elastic member interposed in the connecting member between the inner and outer hubs, and the elastic member prevents the torque caused by the buckling of the spline between the two hubs during torque transmission. It is characterized by absorbing vibrations.

〔Example〕

A specific embodiment in which the present invention is applied to an electromagnetic brake will be described below with reference to FIGS. 1 to 6. 1 and 2 are a longitudinal sectional view and a partially enlarged view of the whole part showing one embodiment, and FIGS. 3 to 6 are sectional views showing other embodiments, respectively. Portions corresponding to those in the figures are given the same reference numerals, and their explanations will be omitted. First, the embodiment shown in FIGS. 1 and 2 will be explained. In this invention, the connecting member 13 is press-fitted into the axial hole of the outer hub 8 and the inner circumference of the cylindrical holding member 15. As in the case of FIG. 7, this connecting member and the outer hub are firmly connected so that they do not slide relative to each other, and the pressure contact conditions for the connecting member 13 and the holding member 15 are as shown in FIG. In the same way that a contact friction force is set between the connecting member and the inner hub 11 for sliding in the axial direction, a contact friction force is set between the connecting member and the holding member 15. Note that the holding member 15 has an elastic member 16 such as an O-ring fitted on its outer periphery, and
The holding member is press-fitted into the axial hole 17 of the inner hub 11, and the axial movement of this holding member is controlled by the protrusion 18 at the inner end of the hole 17 and the outer end of the hole. It is restrained by plate 19. However, the holding member can freely move in directions other than the axial direction within the deformation range of the elastic member 16, and within this range, the holding member can move relative to the inner hub 11 while being accompanied by the connecting member 13. I'm starting to get it. The connecting member 13, the holding member 15, and the elastic member 16 constitute the main part of the gap adjusting device, and a plurality of these members are provided on the circumference of the hub.

The embodiment of the present invention is configured as described above, and when the armature 4 is attracted by the electromagnetic attraction force, the adjustment effect of the gap _g1 when the transmission friction surface is worn out is determined by the transmission friction surface in the armature suction process. In the final suction stroke corresponding to the wear amount, the connecting member 13 is pulled out from the holding member together with the outer hub 8 by the suction movement of the armature 4 against the contact friction force between the holding member 15, and the armature 4 is When released, the connecting member 13 is not pushed back and only the armature remains in the gap g ₁
It will be moved back by the amount equivalent to ,
The gap _g1 is automatically adjusted by such an operation, and in the present invention, the holding member 15 is fitted to the connecting member 13, and the contact friction force necessary for gap adjustment is maintained between the holding member 15 and the connecting member 13. At the same time, since the holding member 15 is elastically supported by the elastic member 16, the elastic member 16 receives torque vibration caused by the backlash of the spline 12 between the inner and outer hubs 11 and 8 during braking. At this time, depending on the elastic modulus of the elastic member 16, the connecting member 13 will be subjected to torque vibration by the amount of displacement caused by the above-mentioned bounce of the elastic member, but in this case, the spring constant of the elastic member 16 is By setting the torque sufficiently low, the torque vibration can be borne and absorbed by the elastic member 16. Therefore, there is no distortion in the connecting member 13 due to torque fluctuations during torque transmission between the inner and outer hubs during braking, etc., or due to load torque fluctuations.
The contact friction force between this connecting member and the holding member 15 is always kept constant. Note that even if the holding member 15 and the elastic member 16 are arranged axially on the outer periphery of the connecting member 13 as in the embodiment shown in FIG. 3, the operation is the same as in the above embodiment.

FIG. 4 shows another embodiment. In this embodiment, elastic members 20 are provided separately from the connecting member 13 on the circumference of both hubs, alternating with the connecting member 13. The connecting member 13 is held in the same manner as in the above embodiment by the holding member 15, which faces the hole 17 of the inner hub 11 and whose movement in the axial direction is restrained by the inner hub. For adjustment of g ₁ , connect member 1 of armature 4 when suctioning.
3 from the holding member 15, the contact friction force between the two,
Therefore, by resisting the holding force of the holding member 15 against the connecting member 13 and pulling out the holding member by an amount corresponding to the amount of wear on the transmission friction surface, the gap is removed.
The elastic member ₂₀ is press-fitted into the axial holes of both the inner and outer hubs 11 and 8, and the elastic member 20 is press-fitted into the holes in the axial direction of the inner and outer hubs. The elastic member 20 absorbs the torque vibration caused by the vibration. The elastic member 20 is preferably made of hard rubber or a spring pin.

Furthermore, as another embodiment, as shown in FIG. 5, a predetermined contact friction force is provided between the connecting member 23 and the hole of the outer hub 8, and a flange portion 23' is formed at one end of the connecting member 23. However, regarding the gap adjustment effect, the same objective as above can be achieved even if the outer hub 8 is made to slide on the connecting member 23.

In most of the embodiments, a holding member is provided on the inner hub side, and the gap is automatically adjusted by pulling out the connecting member from within the holding member based on electromagnetic attraction force, but the connecting member 13. Even if the relationship of the holding member 15, elastic member 16, etc. to the inner and outer hubs 11 and 8 is changed, the holding member 15 is provided on the outer hub 8 side and the connecting member 13 is provided on the axis of the inner hub 11. The outer hub 8 is press-fitted into the hole in the direction so that it cannot move relative to the hub, and when adjusting the gap _g1 , the outer hub 8 and the holding member 15 slide this holding member against the connecting member 13. Even if you try to follow the armature while moving, the gap g ₁
Needless to say, it is possible to perform the automatic adjustment action and at the same time avoid a decrease in the contact friction force between the connecting member and the holding member as in the case described above. Further, in the embodiment, the case where the present invention is applied to an electromagnetic brake is illustrated, but even if it is applied to an electromagnetic clutch, the essential operation and effect are exactly the same as in the above case.

Furthermore, in the embodiment, when used as an electromagnetic clutch, the present invention is applied to a type in which the coil side rotates, but a rotor is interposed between the coil side and the armature, and a rotor is inserted between the rotor side and the armature side. It goes without saying that similar effects can be obtained even if the coil is of a so-called stationary type, in which torque is transferred and received.

[Effects of the Invention] As described above, the present invention provides a connecting member between the inner and outer hubs, and when the armature is suctioned, the armature support side An electromagnetic clutch or a brake that moves the hub to follow the armature against the contact friction force between the connecting member and the hub, or directly between the two hubs, or both. An elastic member is interposed between one of the hubs and the connecting member, and this elastic member absorbs torque vibrations caused by buckling of the spline portions of both hubs, so that the connecting member absorbs torque vibrations. Therefore, the contact friction force necessary for gap adjustment for this connecting member can be maintained constant, and the gap g caused by torque vibrations that occur when the clutch is engaged, when the brake is applied, etc. It is possible to solve problems such as the phenomenon of decrease in _{g 1} , maintain the gap g ₁ constant at all times, and provide an electromagnetic clutch/brake with stable armature suction and release characteristics.

[Brief explanation of drawings]

1 and 2 are longitudinal sectional views and partially enlarged sectional views of an electromagnetic clutch/brake showing one embodiment of the present invention, and FIGS. Cross-sectional views showing examples, FIGS. 6 and 7
The figures are a longitudinal sectional view and a partial view of a conventional electromagnetic clutch/brake. 4... Armature, 5... Leaf spring, 8... Outer hub, 11... Inner hub, 12... Spline, 13... Connection member, 16, 20... Elastic member, 23... Connection member ( with flange).

Claims (1)

[Scope of Claims] 1. Inner and outer hubs that are separated from each other and engaged by splines, an armature that is supported by one of the hubs via a leaf spring, and that connects the two hubs. , a hub on the side that supports the armature of both hubs, which is provided with a connecting member that is capable of sliding relative to one of the hubs in the axial direction and that maintains a predetermined frictional force against the relative sliding. An electromagnetic clutch or brake that uses suction movement of the armature to move in the same direction as the armature against the above-mentioned frictional force to adjust the space between the armature and the transmission friction surface facing it. The above-mentioned connecting member is press-fitted into one of the inner and outer hubs, and fixed to the other hub.
An automatic air adjustment device for an electromagnetic clutch/brake, characterized in that it is mounted with a holding member and an elastic member interposed therebetween, and the elastic member absorbs torque vibrations caused by buckling of the spline portion. . 2. Inner and outer hubs that are mutually divided and engaged by splines, an armature that is supported by one of the hubs via a leaf spring, and both hubs that are connected and A connecting member is provided that is capable of relative sliding in the axial direction and maintains a predetermined frictional force against the relative sliding, and the hub on the side that supports the armature among the two hubs is moved by suction of the armature. The connecting member is used in an electromagnetic clutch or brake which is moved in the same direction as the armature against the frictional force to adjust the space between the armature and the transmission friction surface facing it. , is press-fitted into one of the inner and outer hubs, and attached to the other hub with a holding member interposed, and separately from the connecting member, is inserted into a hole on the circumference of both the inner and outer hubs. An automatic air adjustment device for an electromagnetic clutch/brake, characterized in that elastic members are installed alternately with the connecting members, and the elastic members absorb torque vibrations caused by backlash of the spline portion. . 3. Inner and outer hubs that are mutually divided and engaged by splines, an armature that is supported by one of the hubs via a leaf spring, and two hubs that are joined together and A connecting member is provided that is capable of relative sliding in the axial direction and maintains a predetermined frictional force against the relative sliding, and the hub on the side that supports the armature among the two hubs is moved by suction of the armature. One of the connecting members in an electromagnetic clutch or brake that is moved in the same direction as the armature against the frictional force to adjust the space between the armature and the transmission friction surface facing it. A flange portion is provided at the end, and the connecting member is inserted into one of the inner and outer hubs with a predetermined contact friction force, and the flange portion of the connecting member is brought into contact with the hole side of the other hub. Furthermore, apart from the above-mentioned connecting member,
An electromagnetic device characterized in that elastic members are installed in holes on the circumferences of both the inner and outer hubs alternately with the connecting members, and the elastic members absorb torque vibrations caused by buckling of the spline portion. Automatic air adjustment device for clutch and brake.