JPS633472Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to an automatic gap adjustment device for electromagnetic clutches/brakes. The present invention relates to an automatic gap adjustment device for an electromagnetic clutch/brake which adjusts the gap to ensure a set gap at all times.

(Prior Art) Conventionally, the so-called leaf spring drive method using a leaf spring S in the dynamic coupling part shown in FIG. (So-called crash noise)
It has the advantage that there is no However, as the friction surface of armature A wears out due to repeated coupling/braking, the gap G between the rotor R and the friction surface of armature A widens, resulting in a longer armature suction time and a shorter release time. This causes a problem that the operating time changes and responsiveness is not guaranteed. Further, when the wear progresses further and the gap G becomes larger than a preset gap, the attraction force due to the coil magnetomotive force becomes smaller than the release force (anti-attraction force) of the leaf spring, and the armature is not attracted and becomes inoperable. Therefore, in the case of reuse, it is necessary to adjust the gap in the friction surface to narrow it to the set value, and the current situation is that the gap is adjusted several times over the life of the friction surface, and maintenance is required. Management is extremely difficult.

In addition, from the above point, as disclosed by the applicant in Utility Model Application No. 52-82882 (Utility Model Application No. 54-9260), the hub is connected to the inner hub in the axial direction relative to the inner hub. The outer hub is fitted to allow relative movement, and a friction member is press-fitted between the two hubs to hold the outer hub movably by electromagnetic attraction. There is an automatic air gap adjustment type that allows the hub to move. However, in this case, there is a limit to the setting of the rigidity of the friction member in order to make it movable by electromagnetic attraction, and furthermore, this friction member was used as a means of transmitting torque from the outer hub to the inner hub, so the friction member There was a risk that the outer hub would wear out due to slipping under load, reducing the retaining force of the outer hub, or could break due to overload.

Furthermore, from this point of view, Utility Model No. 55-34533
In addition to the above configuration, there is also an electromagnetic coupling device disclosed in the above publication in which both the inner and outer hubs are dynamically coupled by a guide pin for torque transmission. However, in this method, in order to prevent the guide pin from interfering with the holding force of the hub by the friction member, it is necessary to loosely fit the guide pin fixed to one of the inner and outer hubs into the other hub. Therefore, when torque transmission is started, the guide pin and the hub into which the guide pin is loosely fitted cause a severe collision, and this repetition causes concern about the strength and durability of the guide pin.

(Problems to be Solved by the Invention) Therefore, the present invention includes a torque transmission means between the inner and outer hubs in order to reduce or eliminate the load on the friction member for holding the hub in the above-mentioned automatic gap adjustment type electromagnetic clutch/brake. The technology to be solved is that, when separately provided, this means fixedly connects both the inner and outer hubs against movement in the rotational direction, but allows relative movement in the axial direction. This will be a major issue.

(Means for solving the problem) The technical means for solving the above problem consists of a yoke provided on the driven shaft, a rotor magnetized by a coil provided on the yoke, and a rotor that is attracted to the rotor. In an electromagnetic clutch/brake consisting of an armature to be detached and a hub supporting this armature, the hub is divided into an inner hub and an outer hub fitted to the inner hub so as to be movable relative to the inner hub in the axial direction, An elastic member is inserted between these two hubs along the axial direction to dynamically connect both hubs and to exert a certain holding force against free movement of the outer hub in the axial direction based on frictional resistance with both hubs. The armature is connected to the outer hub via a release leaf spring, and the armature is connected between the sides of both hubs, and has strong rigidity in the rotational direction of the hub, and is supported by the elastic member in the axial direction. This is done by using a torque transmitting plate spring designed to have a spring constant that is weaker than the holding force of the outer hub.

(Function) The leaf spring for torque transmission has strong rigidity in the rotational direction of the hub, so it effectively bears the burden of torque transmission from the outer hub to the inner hub. Furthermore, since it is fixed across the sides of both hubs, no collision or impact occurs between the leaf spring and both hubs when torque transmission begins. Furthermore, since the leaf spring has a weak spring constant in the axial direction, it allows the outer hub to move in the axial direction, and this movement is absorbed by its own elastic deformation.

(Example) Hereinafter, an example of the present invention will be specifically described based on FIGS. 2 to 6 of the drawings.

Reference numeral 1 denotes a driven shaft (not shown) mounted on, for example, a crankshaft or camshaft of an engine, and a yoke (not shown) housing and fixing a coil is rotatably mounted on this shaft 1. 2 is a rotor that is pivotally attached to the shaft 1. A hub generally designated by the reference numeral 3 is attached to the shaft 1 so as to face the rotor 2, and the hub 3 is connected to an inner hub 4 that is attached to the shaft 1 in an axial direction with respect to the inner hub 4. The outer hub 5 is provided so as to be movable in the rotational direction and to maintain rotational force in the rotational direction. For the purpose of supporting the interlocking relationship between the two, an elastic member 6 such as a spring pin having an appropriate spring constant is inserted into the axial sliding surfaces of the two. The structure of the elastic member 6 and its insertion structure are those known in the art for automatic air gap adjustment type electromagnetic clutches/brakes.

Further, an annular leaf spring 7 having a notch hole is provided between the inner hub 4 and the outer hub 5. In this example, the inner peripheral vertical portion 7' of the leaf spring 7 is connected to the inner hub 5. The outer hub 5 is fixed to the side surface of the outer hub 5 with several setscrews 8, and the peripheral vertical portion 7 provided through the inclined bent portion 7'' for increasing absorption capacity is attached to the outer hub 5 with an adjusting bolt and nut to be described later. The leaf spring 7 is capable of transmitting the rated torque, and the outer hub 5 is axially rotated by the suction force of the rotor 2 by the required amount of wear following the inner hub 4. It is designed to have strong rigidity in the rotational direction and a spring constant as low as possible in the axial direction so that it can be moved in both directions.

An annular armature 9 is provided adjacent to the outer hub 5 of the hub 3 and facing the rotor 2, and is integrally attached to the outer hub 5 via an annular leaf spring 10. To explain how to attach this armature 9, outer hub 5, and leaf spring 10, in this example, the armature 9 is loosely fitted into the annular notch 5' of the outer hub 5, and the circumference of the armature 9 that is loosely fitted is Counterbore holes 11 are provided at three equal positions, and the plate spring 10 is attached to the outer hub 5 using the stepped shaft portion of the adjuster bolt 12 inserted through the counterbore hole 11 and the nut 13. installed.

Further, leaf springs 10 are attached to the armature 9 via rivets 14 at three equally spaced positions on the circumference of the armature 9 at positions that do not conflict with the adjusting bolts 12. This leaf spring 10 has the function of transmitting torque and releasing the armature 9.

Next, the operating state of this embodiment will be explained based on FIG. 2, FIG. 5, and FIG. 6. First, the normally set gap is as shown in FIG.
neck side of the bolt head (right side in the drawing)
and the bottom of the counterbore hole 11 of the armature 9, and this gap G is equal to the friction surface gap G' between the rotor 2 and the armature 9. When current is passed through the coil in this state, the yoke is excited, and the lines of magnetic force generated thereby magnetize the rotor 2, and an attractive force is generated in the rotor 2. This suction force overcomes the release force of the leaf spring 10 and causes the armature 9 to move in the axial direction by the set gap G, and is adsorbed and connected to the rotor 2, resulting in the state shown in FIG. As a result, the torque becomes armature 9
→ leaf spring 10 → outer hub 5 → leaf spring 7 → inner hub 4 → shaft 1.

Further, when the power supply is stopped, the attractive force of the rotor 2 is instantly reduced, and the armature 9 is pulled back toward the outer hub 5 by the releasing force of the leaf spring 10.
By the way, if the friction surface of the armature 9 is worn out due to use, the suction force of the rotor 2 will overcome the holding force of the elastic member 6 inserted between the inner hub 4 and the outer hub 5, and the counterbore of the armature 9 will be damaged. The bottom of the hole 11 draws the adjusting bolt 12 toward the rotor. This pulling force moves the outer hub 5 toward the rotor in the axial direction, and also extends the inclined bent portion 7'' of the leaf spring 7. Therefore, the outer hub 5 moves the sliding surface of the inner hub 4 toward the rotor by the amount of wear. In this way, the outer hub 5 can automatically slide toward the rotor side in the axial direction by the necessary amount of wear following the inner hub 4, and unlike the conventional method, the outer hub 5 can slide toward the rotor side in the axial direction, resulting in the state shown in Fig. 6. Almost no adjustment is required. Figures 11 and 12 compare the characteristics of this embodiment and the conventional example. Point P in Figure 11 is the point where suction is impossible.

As described above, since the leaf spring 7 bears the burden of torque transmission, overload on the elastic member 6 can be avoided, and since the leaf spring 7 is fixedly attached to both hubs 4 and 5, the torque can be transmitted. Since the start of transmission is smooth and there is no collision or impact, there is no concern about the strength or durability of the leaf spring 7 even after long-term use.

In addition, FIGS. 7 to 9 show other examples of the present invention.
To explain the diagram, in this example, the hub 3A includes an inner hub 4A having a notch on the peripheral side surface;
It is divided into an outer hub 5A, a part of which is loosely fitted into this notch, and an elastic member 6A is inserted between the inner hub 4A and the outer hub 5A in a direction perpendicular to the radial joint surface of the two. The outer hub 5A is configured to be movable in the axial direction with respect to the inner hub 4A and to maintain rotational force in the rotational direction.

Further, the leaf spring 7A has approximately the same configuration as described above, but contrary to the above, it is fixed to the rotor 2A side with a set screw 8A and an adjusting bolt 12A, and this leaf spring 7A is attached to a rivet 14A, which will be described later. Corresponding parts are cut out due to their structure. In addition, the leaf spring 10A is fixed across the armature 9A and the outer hub 5A via the adjusting bolt 12A and the rivet 14A, and the relationship between the armature 9A, the outer hub 5A, the rotor 2A, etc., and their functions are the same as in the above-mentioned embodiment. Since it is the same as , it is omitted.

In this embodiment, in addition to the same functions and effects as in the first embodiment, since the leaf spring 7A is fixed to both the inner and outer hubs, the elastic member 6A is When the load is released and the elastic member returns to its original shape, a gap is created between the inner and outer hubs by the amount of the above deviation. This can avoid the problem that the holding position of the outer hub 5A is distorted due to this.

Next, another embodiment of the present invention will be described with reference to FIG. 10. In this embodiment, an elastic member 6B
is formed into a ring shape along the outer circumferential surface of the inner hub 4B of the hub 3B, and for installation, the inner hub is housed in a groove provided along the inner circumferential surface of the outer hub 5B. It is elastically press-fitted into the outer peripheral surface of 4B. That is, by utilizing the contact pressure between the outer circumferential surface of the inner hub 4B and the inner circumferential surface of the ring-shaped elastic member 6B, the outer hub 5B is moved in the axial direction by an amount corresponding to the wear of the transmission friction surface of the armature 9B. It was designed so that

Note that the rotor 2B, leaf springs 7B, 10B, etc. are the same as those shown in FIG. 2, so their explanations will be omitted.

(Effects of the Invention) In an electromagnetic clutch/brake of automatic air gap adjustment type, the present invention can avoid overloading the elastic member for holding the hub, and does not cause concerns about the strength and durability of the torque transmission means. This allows reliability to be maintained over a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main part of a conventional leaf spring drive system, Fig. 2 is a cross-sectional view of an example of the present invention, showing the state when the coil is not energized, and Fig. 3 is a right side view of the main part of Fig. 2. Figure 4 is a left side view of the main part of Figure 2, Figures 5 and 6 are both sectional views showing the operating state when the coil is excited in Figure 2, and Figure 6 is when the friction surface is worn. shows. Fig. 7 is a sectional view showing another example of the present invention, Fig. 8 is a right side view of the main part of Fig. 7, Fig. 9 is a left side view of the main part of Fig. 7, and Fig. 10 is a further FIG. 3 is a cross-sectional view showing a main part of another example of the present invention. Furthermore, FIGS. 11 and 12 are characteristic comparison diagrams comparing the performance of the present invention and the conventional leaf spring drive system, and in both figures, reference numeral 21 is a diagram for the conventional system.
Reference numeral 22 is a diagram according to the present invention. 2, 2A, 2B...Rotor, 3, 3A, 3B...
...Hub, 4, 4A, 4B...Inner hub, 5,
5A, 5B... Outer hub, 6, 6A, 6B...
...Elastic member, 7,7A,7B...Plate spring, 9,9
A, 9B...armature, G, G'...void.

Claims (1)

[Claims for Utility Model Registration] A yoke provided on a driven shaft, a rotor magnetized by a coil provided on this yoke, an armature that is attracted to and detached from this rotor, and a hub that supports this armature. In the electromagnetic clutch/brake, the hub is divided into an inner hub and an outer hub fitted to the inner hub so as to be movable relative to the inner hub in the axial direction, and the two hubs are dynamically connected between the two hubs. At the same time, an elastic member is inserted in the axial direction that exhibits a certain holding force against free movement of the outer hub in the axial direction based on the frictional resistance with both hubs, and a leaf spring for release is installed in the outer hub. The armature is connected through the hub, and a spring constant is designed to have strong rigidity in the rotational direction of the hub, but weaker in the axial direction than the holding force of the outer hub by the elastic member. An automatic air gap adjustment device for an electromagnetic clutch/brake, characterized in that a plate spring for torque transmission is fixed across.