JPS6238031Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a manual release device for manually releasing the braking state of an electromagnetic brake installed in, for example, a crane motor.

The electromagnetic brake for this type of application is used as a safety brake, and when no current is supplied to the excitation coil, braking is applied by the spring force of the spring or the electromagnetic attraction force of the permanent magnet, and the electromagnetic coil is stopped. A so-called spring-close type, etc., in which braking is released by power supply, is used, and the control circuit of the excitation coil of the electromagnetic brake is linked with the power circuit of the crane motor, so that the electromagnetic brake cannot be excited by itself. It is becoming.

However, if there is a power outage during assembly or adjustment during the manufacturing process, or during hoisting or lowering of the crane,
When lowering a lifted object safely to the ground, it is desirable to have a configuration in which the braking state can be released by manual operation, regardless of motor operation, and many devices have been proposed for this purpose, but none of them. It also has a complicated structure and is expensive.

The present invention has been developed in view of this problem, and aims to provide a device with a simple structure and extremely low cost.

Examples illustrating the present invention will be described below.
In the drawings, reference numeral 1 denotes a yoke that houses an excitation coil 2 in a concave portion opening on one side, and is fixed to a stationary part of a braked equipment such as a bracket of a crane motor.
A ring-shaped armature 3 is supported on the yoke 1 by a plurality of bolts 4 protruding from the sides thereof so as to be able to slide on the bolts, and one side of the armature is attached to the side of the yoke 1. It faces the side surface of the magnetic pole. Reference numeral 5 denotes a fixed brake plate with one side facing one side of the armature 3, which is supported by the tip of the bolt 4, and whose position in the axial direction can be adjusted by rotating a nut screwed onto the bolt. ing. Reference numeral 6 denotes a ring-shaped brake disk interposed between the armature 3 and the fixed brake plate 5, and is spline-coupled to the spline hub 7 at the inner circumference. The spline hub 7 is connected to a braked shaft (not shown) such as a motor shaft of a crane motor. Reference numeral 8 denotes a braking spring inserted into each of a plurality of holes provided in the yoke 1, and presses the armature 3 toward the fixed braking plate 5 at one end. 9 is a shaft that rotatably passes through a hole provided horizontally in the yoke 1, and is attached to both ends and the armature 3.
The left and right circumferential surfaces of the shaft 9 are connected by a string-like material 10 such as a rope, wire, belt, or chain, and a handle 11 for rotating the shaft is attached to one end of the shaft 9.

The embodiment of the present invention is constructed as described above, and the brake disc 6 is fixed to the armature 3 by the elastic force of the spring 8 when no current is supplied to the excitation coil 2, similar to the conventional electromagnetic brake of this type. The brake disc 6 is clamped between the brake plates 5, and a brake is applied to a brake shaft (not shown) that is dynamically connected to the brake disc 6 via a spline hub 7. When current is supplied to the excitation coil 2 in this position, an electromagnetic attraction force is applied to the armature 3, so that the armature is attracted to the yoke 1 side against the elastic force of the spring 8, and the clamping pressure on the brake disc 6 is increased. This releases the brake on that brake disc and therefore on the braked shaft.

The above is the original action of the electromagnetic brake, but in the case of a manual release device, the string 10 is usually relaxed, and when no current is supplied to the excitation coil 2, the armature 3 is fixed to the brake plate by the force of the brake spring 8. 5, and the brake device is in a braking state. When the shaft 9 is rotated by operating the handle 10 in this state, the string-like object 10 is wound around the shaft 9, and one end of this string-like object The armature 3 connected thereto is moved toward the yoke 1 against the force of the braking spring 8, and the braking state is released.

Also, the armature 3 will be braked if the handle 11 is rotated in the opposite direction to the above to rewind the string-like object 10, or the armature 3 can be braked by releasing the hand from the handle and removing the force in the direction of winding the string-like object against the handle. The brake spring 8 pushes the brake device back toward the braking side, and the brake device returns to its original braking state. In the embodiment, the shaft 9 is inserted into a through hole provided in the yoke 1 and supported by the yoke, but the shaft 9 may be supported at an appropriate location of a braked device equipped with a brake device.

In this case, the braking condition can be manually released by simply connecting the shaft, which can be rotated by handle operation, and the armature directly with a string-like object, so the number of parts is extremely small, and the structure is also extremely simple. The device can be obtained at low cost.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a sectional view of only the upper half, and FIG. 2 is a side view. 1... Yoke, 2... Excitation coil, 2... Armature, 9... Shaft, 10... String-like object.

Claims (1)

[Scope of utility model registration request] An armature facing the yoke that houses the excitation coil and a shaft provided on the yoke side perpendicular to the suction direction of the armature are connected by a string-like object, and the rotation of the shaft causes the string-like object to connect to the shaft. A manual release device for an electromagnetic brake characterized by moving an armature by wrapping an object around it.