JPS59133840A - Electromagnetic clutch and brake - Google Patents

Abstract

PURPOSE:To desirably carry out torque transmission and braking, by attracting an armature to a rotor by a solenoid coil to transmit rotation of a main shaft and adjusting a spacing of attraction by a coil spring and a screw. CONSTITUTION:When voltage is applied to a solenoid coil 19, an armature 5 is excited by a field core 4 through a rotor 3, and is magnetically attracted to the rotor 3. A pulley 8 connected through a leaf spring 9 to the armature 5 is rotated with the rotor 3 integrally fixed to an output shaft 1 in the same direction, and a driven shaft is rotated through a belt. When application of voltage is stopped, excitation of the armature 5 is released and is separated from the rotor 3 by the leaf spring 9. At this time, a back surface 5a abuts against a flange 13A of a brake cover 13, thereby preventing idle rotation due to inertia. In the event that a spacing of attraction is enlarged by abrasion of opposite surfaces of the rotor 3 and the armature 5, a nut 17 is screwed to slightly move the brake cover 13 to the rotor 3.

Description

[Detailed Description of the Invention] This invention relates to an electromagnetic clutch/brake that can freely transmit torque and brake an output rotating member when torque is cut off.1 In garden tractors and other agricultural and gardening machines, etc.
An annular rotor, which serves as an input rotating member for an electromagnetic clutch/brake, is fixed concentrically to the output shaft of an internal combustion engine or motor, either directly or indirectly through a reducer, etc., and an annular rotor that can be magnetically attracted to the front of the rotor. The armature is required to be integrally movable and axially movable relative to the output rotating member, such as a pulley, while being braked by bringing the armature in a demagnetized state into frictional contact with a fixed phase.

That is, by braking the armature, the torque transmission is cut off for the members to be ashed, such as tilling blades, rotary reaping blades, rotary shearing blades, etc., which are belt-hung on the side of the output rotating part that rotates integrally with the armature. It is required to improve safety by being able to stop at the same time.

By the way, the gap between the rotor and armature when they are separated is usually around 0.5 my+, and if cut grass or dirt gets into this gap, the specified torque will not be transmitted. .

However, if the gap becomes too thick due to wear or other causes, it will be difficult to magnetically attract the armature, so it must be possible to adjust the gap, but complex structures are difficult to handle and require time to adjust. Since this would reduce work efficiency, there has been a strong desire to develop electromagnetic clutches and brakes that solve these problems.

The present invention provides an electromagnetic clutch/brake that meets the above-mentioned needs, and includes an annular rotor fixed to a device output shaft, an annular field core facing the back side of the rotor, and a magnetic field core facing the front side of the rotor. An annular armature facing directly to each other so as to be freely suctionable, an output rotating member concentrically supported on the output shaft of the device so as to freely rotate, and a torque transmitting and armature return plate connecting the output rotating member and the armature. The present invention is characterized in that it has a spring cover on the back side of the field core, and supports the brake cover so that its position in the axial direction can be freely adjusted by interposing a compression coil spring between the mounting plate and the brake cover. .

Next, the electromagnetic clutch/brake of the present invention will be explained by way of embodiments with reference to the drawings.

FIG. 1 shows an embodiment of the electromagnetic clutch/brake of the present invention in a longitudinal side view. As shown in the drawings, the electromagnetic clutch/brake of the present invention has a key 2 attached to the output shaft of a device such as an internal combustion engine, an output shaft of a motor, or an output shaft of a reducer attached to an internal combustion engine or motor. An annular rotor 3 fixed integrally using a rotor 3, an annular field core 4 facing the back side of the rotor 3, and an annular field core 4 facing the rotor 3 so as to be freely magnetically attracted to the front surface 3a of the rotor 3. a ring-shaped armature 5, a pulley 8 as an output rotating member that is coaxially supported on the output shaft 1 via a sleeve 6 and a bearing 7 so as to freely rotate; and a torque that connects this pulley 8 and the armature 5. A leaf spring 9 for transmission and armature return, a mounting plate 12 fixed to the back surface of the field core 4 and fixed to the equipment frame IO with a plurality of poles 11, and a back surface 5a near the outer periphery of the armature 5. It has a cylindrical brake cover 13 having an inward flange portion 13A that can freely come into contact with it, and inserts it 16 into three positions where the mounting plate 12 and the brake cover 13 face each other, and on the back side of the brake cover 13. Each bolt 16 is screwed into a bolt 17.

The bolt 16 is attached to the mounting plate 12 and the brake cover 1.
3, and the compression coil spring 18 is fitted between the recess and the nut 17.
The structure is such that the position in the axial direction of the brake cover 13 being pushed is determined.

The field core 4 has a built-in electromagnetic coil 19 and is inserted into an annular groove 3A that is open on the back side of the rotor 3. Further, the leaf spring 9 has one end connected to the armature 5.
while fixing the other end to the pulley 8 with a rivet 20.
a rectangular leaf spring fixed by a rivet 21 to the
Usually three pieces are used, but sometimes one annular corrugated plate spring is used. Further, the rotor 3 is provided with arcuate holes 22 and 23 arranged concentrically intermittently in the annular circumferential direction, and the armature 5 is provided with arcuate holes 22 and 23 arranged intermittently in the annular circumferential direction, and the armature 5 is provided with arcuate holes 22 and 23 arranged circumferentially at positions facing between the arcuate holes 22 and 23. Arc-shaped holes 24 are bored in an intermittent array in the direction. These arcuate holes are formed by the electromagnetic coil 19.
This hole is provided to detour the magnetic flux generated by applying a voltage to the armature 5 so that it passes through both the inner periphery 9 portion and the outer periphery 9 portion.

FIG. 2 shows the brake cover 13 in a front view.

The brake cover 13 has a portion where the hole 15 is formed at 12
Seven lanterns are provided at equal angle division positions of 0° to prevent bending.

The electromagnetic clutch/brake of the present invention having the above-mentioned configuration has a rotor 3 attached to the output shaft 1 of the device, as shown in FIG.
The gap between the surface 3a of the rotor 3 and the armature 5 is maintained at a predetermined size by fixing the pulley 8, supporting the pulley 8 so that it can freely rotate, and adjusting the tightening of the NAND 17.

When a predetermined voltage is applied to the electromagnetic coil 19 in this state,
The generated magnetic flux passes from the field core 4 through the rotor 3 to the armature 5, and the excited armature 5 magnetically attracts the front surface 3aK of the rotor 3.

When the armature 5 magnetically attracts the rotor 3, the plate springs 9
A pulley 8, which is connected to the armature 5 through a belt, rotates in the same direction as the rotor 3, which rotates together with the output shaft 1, and rotates a driven shaft, which is connected through a belt (not shown). Since, for example, a tilling blade, a rotating reaping blade, and other necessary members are attached to the driven shaft (not shown), these parts are rotated by power.

When the voltage application to the electromagnetic coil 19 is stopped, the armature 5 is demagnetized and separated from the υ rotor 3 by the elastic return force of the leaf spring 9, and is attached to the inward flange portion 13A of the brake cover 13 on the back side 5a. are in contact with each other, and idling due to inertia is prevented.

If both the rotor 3 and the armature 5 wear out due to long-term use and the gap has expanded, tighten the nut 7 and move the position of the brake cover 13 slightly in the direction of the rotor 3 to normalize the gap again. The dimensions can be 3
In particular, since the brake cover 13 is cylindrical and surrounds the opposing portion of the rotor 3 and armature 5, it prevents grass juices etc. flying from the sides from entering the gap between the rotor 3 and armature 5. Since this can be prevented, there will be no torque transmission failure due to the intrusion of grass juice, etc.

As is clear from the above description, the electromagnetic clutch/brake of the present invention is extremely simple in structure and handling, and has the ability to transmit torque and prevent slippage in agricultural and horticultural machinery such as garden tractors. Electromagnetic clutch・
It is often used as a brake, especially since the brake cover is supported with elasticity by a compression coil spring, making it difficult to tighten nuts.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of the electromagnetic clutch/brake of the present invention, and FIG. 2 is a front view of the braking force/brake. In the drawings, 1... Output IpH1, 3... Rotor, 3a front,
4. Field core, 5. Armature, 5a... Back, 8. Pulley, 9
... Leaf spring, 10 ... Equipment frame, 12 ... Mounting plate, 13 ... Brake cover. 13A, 13B・Flange portion, 13C・Peripheral body portion, 14, , 15・・Bolt through hole, 16・Bolt, 17・・Nut, exit; Section 6 Ogura Clutch Co., Ltd. agent Tomi 1) Kazuo and 1 other person

Claims (1)

[Claims] An annular rotor fixed to the output shaft of the device, an annular field core arranged on the back side of the rotor, an annular armature facing directly to the front surface of the rotor so as to be freely magnetically attracted to the rotor, and an output shaft of the device. an output rotating part side that is concentrically supported so as to freely rotate on the top; a torque transmitting armature return plate that connects the output rotating member and the armature;
An electromagnetic clutch characterized in that a compression coil spring is fully interposed between a mounting plate fixed to the back surface of the field core, the arithmetic plate and the brake cover, and the brake cover is supported so that the axial force can be adjusted at the same position. ·brake.