JPH09324830A - Deenergization operated type electromagnetic brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the separation of a plating layer caused by being used for many years by applying strong impulsive force, by providing a braking spring by which a magnetic stainless steel-made armature is pushed and pressed to a brake disc. SOLUTION: When a deenergization condition is set, an armature 8 ms abutted on an inner disc 11 by spring force, and a projection 8a is brought into contact with the wall surface of an engaging groove 9c. However, magnetic pole plates 4, 5 and the armature 8 are manufactured by magnetic stainless steel, therefore the separation of a plating layer due to impulsive force may not cause, and also sliding between the projection 8a and the wall surface of the engaging groove 9c may not be deteriorated by rust, and further a pressure receiving member 9 is also made of stainless steel, thus the smooth action of the armature 8 can be retained in a satisfactory condition for many years. Also, when an energization condition is set, the armature 8 is magnetically attracted to the magnetic pole plates 4, 5 against the spring force, damps impulsive force applied to a field core 1, and prevents the separation of the plating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to rust prevention measures for non-excitation actuated electromagnetic brakes.

[0002]

2. Description of the Related Art A conventional non-excitation actuated electromagnetic brake applies a frictional engagement between an armature pressed by a spring force of a braking spring and a brake disc mounted on a braked shaft of a machine to be braked so that the braked shaft can be controlled. This structure releases the braking of the shaft to be braked by braking and simultaneously magnetically attracting the armature to the field core against the spring force of the braking spring.

Further, the field core containing the armature and the electromagnetic coil serves as a magnetic circuit of the magnetic flux generated by energizing the electromagnetic coil, and is therefore made of a low carbon steel for machine structure having a good magnetic permeability. . Furthermore, the surfaces of these members exposed to the outside are plated with nickel or the like.

[0004]

In the non-excitation actuated electromagnetic brake, when the armature is magnetically attracted to the magnetic pole surface of the field core, a strong impact force acts on these members, so that the inertial rotation of the brake disc is increased. When the armature is brought into contact with the armature, a strong impact force acts on the armature and a member that regulates the rotation of the armature, so that the plating layer may be peeled off after long-term use. In addition, if rust occurs in the part where the plating layer is peeled off, not only will the aesthetic appearance of the electromagnetic brake be deteriorated, but smoothness of the armature will not be obtained, and quality problems will occur, so it is necessary to take some measures. was there. An object of the present invention is to provide a non-excitation actuated electromagnetic brake which has an excellent appearance for many years and can maintain a smooth operation of an armature.

[0005]

In order to achieve such an object, the non-excitation actuated electromagnetic brake of the first invention is
An electromagnetic coil, a field core on which the electromagnetic coil is housed and exposed to the outside are plated, and a magnetic stainless steel magnetic pole plate fixed to the outer and inner magnetic pole surfaces of the field core, A brake disc, which is disposed so as to face the magnetic pole plate and is mounted on the braked shaft, and a magnetic stainless steel which is provided between the brake disc and the magnetic pole plate and is movable only in the axial direction of the braked shaft. And a braking spring for pressing the armature against the brake disc.

The non-excitation actuated electromagnetic brake having such a structure brakes the braked shaft by frictionally engaging the armature and the brake disc with the spring force of the braking spring. Further, the armature is magnetically attracted to the magnetic pole plate against the spring force of the braking spring to release the braking of the braked shaft. Furthermore, the armature made of magnetic stainless steel is magnetically attracted to the magnetic pole plate made of magnetic stainless steel, and impact force does not directly act on the field core that requires plating treatment, and peeling of the plating layer can be prevented. Also,
Since only the armature and pole plate are made of magnetic stainless steel, the increase in reluctance in the magnetic circuit can be minimized.

The non-excitation actuated electromagnetic brake of the second invention is characterized in that, in the first invention, a demagnetization plate is sandwiched between the magnetic pole surface of the field core and the magnetic pole plate.
With such a structure, even in the non-excitation actuated electromagnetic brake in which the ampere-turn of the electromagnetic coil is designed to be large, the residual magnetic flux in the magnetic circuit quickly disappears, and if the electromagnetic coil is de-energized, the braking spring The spring force can instantly frictionally engage the armature with the brake disc.

[0008]

1 is a sectional view of a non-excitation actuated electromagnetic brake according to an embodiment of the present invention, and FIG.
FIG. 3 is an enlarged cross-sectional view of a main part of a field core. The non-excitation actuated electromagnetic brake shown in the drawings is used as a safety brake by being attached to the shaft end of a rotary shaft (hereinafter referred to as a braked shaft) that constitutes a power transmission path of a general industrial machine. .

The non-excitation actuated electromagnetic brake has a field core 1 made of low carbon steel for machine structure fixed to a housing of an industrial machine (not shown). The field core 1 is formed with an annular groove 1a that is open in the axial direction of the braked shaft 2, and the end faces on the opening side of the annular groove 1a are an outer magnetic pole surface 1b and an inner magnetic pole surface 1c. Also, the magnetic pole surface 1b
Of the magnetic pole surface 1c slightly protruding in the axial direction, and the demagnetization plate (non-magnetic plate) 3 fixed to the magnetic pole surface 1c.
And the magnetic pole surface 1b are flush with each other.

The magnetic pole surface 1b of the field core 1 is fixed with an outer magnetic pole plate 4 formed of magnetic stainless steel in a ring shape, and the magnetic pole surface 1c is sandwiched by the demagnetizing plate 3 and is magnetic stainless steel. The inner magnetic pole plate 5 formed in a ring shape is fixed. The magnetic pole plates 4 and 5 are fixed to the field core 1 with screws (not shown).

Further, the annular groove 1a of the field core 1
An annular storage groove is formed by the space formed between the inner peripheral surface of the magnetic pole plate 4 and the outer peripheral surface of the magnetic pole plate 5. Then, the electromagnetic coil 6 wound in multiple lines is housed in the housing groove and is fixed by an insulating resin. Furthermore,
In the field core 1, spring holes 1d that open in the same direction as the annular groove 1a are formed at positions that divide the circumferential direction into four equal parts,
The through hole 5 aligned with the spring hole 1d is also formed in the pole plate 5.
a is formed. A spring insertion hole is formed by the spring hole 1d and the through hole 5a. A braking spring 7 composed of a compression coil spring is inserted into each spring insertion hole. The braking spring 7 is painted.

The braking spring 7 has its winding end abutted against a magnetic stainless steel armature 8 which faces the magnetic pole plates 4 and 5 with a predetermined air gap therebetween.
Are pressed against the disk portion 9a side of the cup-shaped pressure receiving member 9 fixed to the field core 1 with screws. The cylindrical portion 9b of the pressure receiving member 9 is formed with an engagement groove 9c that is open to the field core 1 side at a position that divides the circumferential direction into eight equal parts.
The armature 8 is arranged so as to be movable only in the axial direction of the braked shaft 2 by fitting the protrusion 8a formed on the outer peripheral surface into the engagement groove 9c. The pressure receiving member 9
Is manufactured from non-magnetic stainless steel.

A hub 10 having a spline groove formed on its outer peripheral surface is key-fitted to the shaft end of the braked shaft 2 to prevent the hub 10 from coming off. Two brake discs 11 (hereinafter referred to as inner discs) having friction plates fixed to both sides are spline-fitted to the hub 10. An outer disk 12 having a projection 12a formed on the outer peripheral surface thereof fitted in an engagement groove 9c of the pressure receiving member 9 is interposed between the inner disks 11. The hub 10, the inner disc 11, and the outer disc 12 are made of non-magnetic stainless steel.

In the non-excitation actuated electromagnetic brake having such a structure, the inner disc 11 and the outer disc 12 are pressed by the spring force of the braking spring 7 in the non-excitation state in which the electromagnetic coil 6 is not energized as shown in the figure. Since it is sandwiched between the armature 8 and the disk portion 9a of the pressure receiving member 9, the braked shaft 2 is held stationary. Further, when the electromagnetic coil 6 is energized, the armature 8 is magnetically attracted to the magnetic pole plates 4 and 5 fixed to the field core 1 against the spring force of the braking spring 7, so that the braked shaft 2 is braked. release.

When the excited state is changed to the non-excited state, the armature 8 is brought into contact with the inner disk 11 which inertially rotates together with the braked shaft 2 by the spring force of the braking spring 7, and the protrusion 8 a of the armature 8 is attached to the pressure receiving member 9. It hits the wall surface of the engaging groove 9c. However, because the armature 8 is made of magnetic stainless steel that does not require plating,
There is no peeling of the plating layer due to impact force as in the past. Further, the sliding between the protrusion 8a and the wall surface of the engagement groove 9c is not significantly deteriorated by rust. Moreover, in this embodiment, since the pressure receiving member 9 is also made of stainless steel, the smooth operation of the armature 8 can be maintained in a very good state for many years.

When the non-excitation state is changed to the excitation state,
The armature 8 resists the spring force of the braking spring 7 and the armature 8
The magnetic force of 5 is absorbed, so that the impact force acting on the field core 1 is mitigated, and peeling of the plating layer is prevented.

Further, in this embodiment, since the demagnetization plate 3 is provided to set the magnetic resistance in the magnetic circuit, even in the non-excitation actuated electromagnetic brake in which the ampere-turn of the electromagnetic coil 6 is designed to be large, the shaft to be braked 2 can be braked instantly.

Next, another embodiment of the present invention will be described.
3 is a sectional view of the field core, and FIG. 4 is a plan view of the pole plate. This embodiment differs from the previous embodiment in that a disk-shaped magnetic pole plate is used instead of the ring-shaped magnetic pole plate.

The field core 13 includes an electromagnetic coil 14
Is formed with a storage groove 13a and a spring insertion hole 13b.
A disc-shaped magnetic pole plate 15 made of magnetic stainless steel is fixed to the magnetic pole surface of the field core 13. An arcuate elongated hole 15a is formed in a portion of the magnetic pole plate 15 facing the electromagnetic coil 14, and a through hole 15b aligned with the spring insertion hole 13b is formed. Like the field core 1, the field core 13 is made of low carbon steel for machine structure, and the surface exposed to the outside is plated with nickel. The non-excitation actuated electromagnetic brake including the field core 13 having such a structure has the same effect as the electromagnetic brake described above.

In the above description, a multi-plate type electromagnetic brake has been described as an embodiment, but the present invention is a single plate type electromagnetic brake in which one inner disk is arranged between the armature and the pressure receiving member. Also applies.

[0021]

As described above, in the non-excitation actuated electromagnetic brake of the present invention, the magnetic pole plate made of magnetic stainless steel is fixed to the magnetic pole surface of the field core, and the armature is made of magnetic stainless steel. , Problems such as malfunction of armature caused by rust were prevented. Moreover, the increase of the magnetic resistance in the magnetic circuit could be minimized.

Further, since the demagnetizing plate is sandwiched between the magnetic pole surface of the field core and the magnetic pole plate, the magnetic resistance in the magnetic circuit can be easily set.

[Brief description of drawings]

FIG. 1 is a sectional view of a non-excitation actuated electromagnetic brake according to an embodiment of the present invention.

FIG. 2 is an enlarged main part sectional view of the field core of FIG.

FIG. 3 is a sectional view of a field core according to another embodiment of the present invention.

FIG. 4 is a plan view of the magnetic pole plate of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Field core 2 ... Braking shaft 3 ... Demagnetization plate 4 ... Magnetic pole plate 5 ... Magnetic pole plate 6 ... Electromagnetic coil 7 ... Braking spring 8 ... Armature 9 ... Pressure receiving member 11 ... Inner disk (brake disk) 13 ... Field core 14 … Electromagnetic coil 15… Magnetic pole plate

Claims (2)

[Claims] 1. An electromagnetic coil, a field core in which the electromagnetic coil is housed and exposed to the outside, and a plating treatment is applied to the surface, and a magnetic stainless steel fixed to the outer and inner magnetic pole surfaces of the field core. Of the magnetic pole plate, a brake disc that is arranged to face the magnetic pole plate and is attached to the braked shaft, and is provided between the brake disc and the magnetic pole plate so as to be movable only in the axial direction of the braked shaft. A non-excitation actuated electromagnetic brake, comprising an armature made of magnetic stainless steel described above and a braking spring that presses the armature against the brake disc. 2. The non-excitation actuated electromagnetic brake according to claim 1, wherein a demagnetizing plate is sandwiched between the magnetic pole surface of the field core and the magnetic pole plate.