JPH0635679U - Electromagnetic clutch or brake with nitriding armature - Google Patents

Abstract

(57) [Abstract] [Purpose] To suppress the occurrence of scuffing and wear on the sliding surface of an armature in an electromagnetic clutch or brake used under conditions where the slip time is long and the amount of heat generated is large. [Structure] The electromagnetic clutch 10 has a rotor 14 to which a lining 18 is fixed, and an armature 16 that faces the rotor 14 in the axial direction. When the coil 22 is energized, the lining 18 slides on the armature 16.
The armature 16 is nitrided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electromagnetic clutch or electromagnetic brake. In particular, the present invention relates to an electromagnetic clutch or brake that is used in a soft stop or in a high energy state, that is, in a condition where the slip time is long and the amount of heat generated is large.

[0002]

[Prior art]

 In the electromagnetic clutch, a lining fixed to the rotor is provided so as to face the armature. The energized coil attracts the armature. Then, the liner and the armature start sliding, and the driving force is transmitted from the rotor side to the armature side.

In the electromagnetic brake, the lining fixed to the stator is provided so as to face the armature. The energized coil attracts the armature. Then, the lining and the armature start sliding, and the braking force acts on the armature.

[0004]

[Problems to be solved by the device]

 In the above electromagnetic clutches and brakes, the armature scuffs when the slip time is long. Scuffing is especially noticeable when the armature is magnetic steel.

When scuffing occurs on the sliding surface of the armature, the temperature of the electromagnetic clutch and the electromagnetic brake rises and abrasion powder is generated. The wear debris widens the air gap between the lining and the armature, resulting in a reduced suction force and a varying coefficient of friction. Therefore, when these phenomena occur, desired characteristics as a clutch or a brake cannot be obtained.

[0006]

Means for Solving the Problems The present invention has solved the above problems by subjecting an armature of an electromagnetic clutch or an electromagnetic brake to a nitriding treatment.

[0007]

[Action]

 When the coil is energized, the armature is attracted towards the lining and both begin to slide. In the case of an electromagnetic clutch, the rotor and armature are gradually synchronized, and in the case of an electromagnetic brake, the armature is gradually decelerated.

In the electromagnetic clutch or electromagnetic brake of the present invention, the armature that slides on the lining is subjected to nitriding treatment, and seizure resistance and wear resistance of the armature are improved. The armature sliding against the lining is free of scuffing, which results in a stable coefficient of friction.

Since the lining wears with the lapse of time, it is preferable to subject the rotor or stator to which the lining is fixed to nitriding treatment. This is because the armature may come into contact with the rotor or stator due to wear of the lining.

[0010]

【Example】

 First, an embodiment in which the present invention is applied to an electromagnetic clutch will be described. As shown in FIG. 1, the electromagnetic clutch 10 concentrically includes an annular clutch stator 12, an annular rotor 14 and an annular armature 16.

The rotor 14 surrounds the clutch stator 12 from three directions in a non-contact state, and faces the armature 16. A lining 18 is fixed to the surface of the rotor 14 facing the armature 16. The lining 18 projects slightly from the rotor 14 in the axial direction. Although the lining 18 is seen to be flush with the rotor 14 in FIG. 2, it actually projects slightly. Reference numeral 20 is a key groove for connecting the rotor 14 to one of the driving member and the driven member.

The armature 16 is made of magnetic steel. Then, in FIG. 2, the armature 16 is subjected to a nitriding treatment at a portion indicated by a thick line. Further, the rotor 14 is also nitrided on the surface facing the armature 16.

When the coil 22 is energized, the nitriding armature 16 is attracted in the axial direction and starts sliding with the lining 18 to transmit the driving force. The reason why the rotor 14 is also nitrided is because it is considered that the armature 16 and the rotor 14 may come into contact with each other due to wear of the lining 18.

Next, an embodiment in which the present invention is applied to an electromagnetic brake will be described. As shown in FIG. 3, the electromagnetic brake 30 concentrically includes an annular brake stator 32 and an annular armature 36. The armature 36 is fixed to the hub 34.

The stator 32 faces the armature 36. A lining 38 is fixed to the surface of the stator 32 facing the armature 36. The lining 38 projects slightly from the stator 32 in the axial direction. Although the lining 38 is seen to be flush with the stator 32 in FIG. 4, it actually projects slightly. Reference numeral 40 denotes a key groove for connecting the hub 34 to the rotating member.

The armature 36 is made of magnetic steel. Then, in FIG. 4, the armature 36 is subjected to a nitriding treatment at a portion indicated by a thick line. The surface of the stator 32 facing the armature 36 is also nitrided.

When the coil 42 is energized, the nitriding armature 36 is axially attracted and starts sliding with the lining 38. The reason why the stator 32 is also nitrided is for the same reason as in the case of the electromagnetic clutch.

Next, under oil lubrication, a comparative test was performed between the normal product (without nitriding treatment) and the product of the present invention. The temperature and the generated torque were measured. Table 1 shows the temperature of the electromagnetic brake.

[0019]

[Table 1]

Table 2 shows the torque (Kgf · m) generated in the electromagnetic brake.

[0021]

[Table 2]

From the test results shown in Tables 1 and 2, the product of the present invention, that is, the electromagnetic brake in which the armature is subjected to the nitriding treatment, has a suppressed temperature rise and is unlikely to cause adhesion. all right. Although the generated torque is slightly reduced by performing the nitriding treatment, since the temperature rise is suppressed, the life can be extended.

[0023]

[Effect of device]

 Since the electromagnetic clutch according to claim 1 or the electromagnetic brake according to claim 3 is obtained by subjecting the armature to nitriding treatment, scuffing does not occur due to sliding with the lining, a temperature rise is suppressed, and stable transmission is achieved. Torque and braking torque can be obtained. As a result, the life can be extended.

The electromagnetic clutch according to the second aspect or the electromagnetic brake according to the fourth aspect can obtain a stable torque even when the armature may come into contact with the rotor or the stator.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of an electromagnetic clutch.

FIG. 2 is an axial sectional view of the electromagnetic clutch of FIG.

FIG. 3 is a partially cutaway perspective view of an electromagnetic brake.

4 is a cross-sectional view of the electromagnetic brake of FIG. 2 in the axial direction.

[Explanation of symbols]

 10 Electromagnetic Clutch 12 Stator 14 Rotor 16 Armature 18 Lining 30 Electromagnetic Brake 32 Stator 34 Hub 36 Armature 38 Lining

Claims (4)

[Scope of utility model registration request] 1. An electromagnetic clutch in which a lining fixed to a rotor faces an armature and a driving force is transmitted between the lining and the armature, wherein the armature is nitrided. Yes, an electromagnetic clutch. 2. The electromagnetic clutch according to claim 1, wherein the lining projects from the rotor toward the armature, and the rotor is nitrided. 3. An electromagnetic brake in which a lining fixed to a stator faces an armature, and a braking force acts between the lining and the armature, wherein the armature is nitrided. , Electromagnetic clutch. 4. The electromagnetic clutch according to claim 3, wherein the lining projects from the stator toward the armature, and the stator is nitrided.