JPH08149751A - Motor with built-in electromagnetic clutch - Google Patents

Abstract

PURPOSE: To realize a highly efficient stabilized operation while reducing noise and shaft free torque by separating the mechanism of motor part and electromagnetic clutch part and applying a full-wave rectified voltage to the coil of an electromagnetic clutch while furthermore making a plurality of grooves in the surface of two clutch pieces opposing to each other. CONSTITUTION: First clutch piece 10 at a clutch part B is secured through an inter-clutch seat 29 tot a shaft 1 and a second clutch piece 11 is fitted movably in the axial direction to the shaft 1 through an output drive member 44, e.g. a pinion gear. The mechanism of a motor part A is separated from the clutch part B in order to limit the frictional point thus reducing the shaft free torque. On the other hand, a full-wave rectified voltage is applied to the coil 34 of an electromagnetic clutch 31 thus reducing noise and vibration thereof. Furthermore, a plurality of grooves are made in the opposing surfaces of the clutch pieces 10, 11 in order to decrease the magnetic resistance thus attracting the second clutch piece 11 strongly to the first clutch piece 10 with a low power while resisting against a reset spring 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor that can be used for applications such as a spring return valve, a spring return damper, and a spring return shutter that can be moved forward when the power is turned on and returned when the power is turned off. Various emergency shutoff applications, motor output torque ON
The present invention relates to a motor that can be used for applications requiring ON / OFF and for applications requiring ON / OFF of motor detent torque (non-excitation holding torque).

[0002]

2. Description of the Related Art As an example of a conventional technique, Japanese Patent Laid-Open No. 5-2
Second Embodiment of "44748" will be described with reference to FIG.

FIG. 9 is a partial sectional side view of an electromagnetic motor with an electromagnetic clutch.

The rotating shaft (shaft) 1 is an electromagnetic clutch 5
When the power is turned on / off, the electric power becomes free at some times and is connected to the rotor 8 at some times to generate output torque. The front bearing 2 and the rear bearing 7 support the shaft 1.

The front bearing 2 is fixed to the front flange 3,
The rear bearing 7 is fixed to the rear flange 6.

The stator (stator) 4 constitutes an electromagnetic motor together with the rotor 8, and the stator 4 has coils 16 and 17 arranged therein to generate a rotating magnetic field or a moving magnetic field to rotate the rotor through a rotating gap 13. 8 is driven to rotate.

A rotor (core) 8 which is rotated by acting on a rotating magnetic field or a moving magnetic field of the stator 4 is fixed to the rotor spacer 9, and an inner diameter portion is axially formed in the shaft 1 with a gap 14 therebetween. It is movable and fitted. Further, the rotor spacer 9 has a first
The clutch piece 10 is fixed.

The second clutch piece 11, which is connected to and disengaged from the first clutch piece 10, is press-fitted and fixed to the shaft 1.
A return spring 12 is arranged between the first clutch piece 10 and the second clutch piece 11.

An electromagnetic coil 20 for operating connection / disconnection of the first clutch piece 10 and the second clutch piece 11 is provided in the electromagnetic clutch 5.

Reference numeral 13 is a rotation gap between the stator 4 and the rotor 8, and 15 is a clutch gap when the first and second clutch pieces are separated. The portion A in FIG. 9 has a motor outer diameter of φ35 (m
m) A motor part of a capacitor type synchronous motor "PTM-24M manufactured by Nippon Pulse Motor Co., Ltd." The rotor 8 is a ferrite rotor having an outer diameter φ16 (mm) and NS24 poles. Taking the AC100V of this motor as an example, the output torque is 120/1 at 50/60 (HZ).
It is 25 (g-cm). The non-excitation detent torque (holding torque) of this motor is 25 (g-cm),
It appears on the shaft 1 only when the electromagnetic clutch 5 is turned on.
Motor coil energization OFF, electromagnetic clutch coil energization OF
The shaft free torque at the time of F is only the friction torque of the shaft 1 and is about 3 (g-cm).

The stator and tooth pole structure of the synchronous motor are conventionally known.

The inner diameter portion of the stator of the electromagnetic clutch 5 is a pair of rings having an L-shaped cross section as shown in FIG. 9, and in the magnetic circuit, the right magnetic pole of the stator of the electromagnetic clutch 5 is the second clutch piece 11. Although the edges are aligned by wrapping, the first clutch piece 10 is arranged with the edge shifted by a dimension C to the left with respect to the left magnetic pole of the stator of the electromagnetic clutch 5. With such a structure, when the coil 20 of the stator of the electromagnetic clutch 5 is energized, the second clutch piece 11, that is, the integrated shaft 1 does not move in the axial direction, and the first clutch piece 10, That is, only the rotor 8 moves to the right in the axial direction, and the rotor 8 and the shaft 1 are connected. In this way, only the rotor moves inside the motor, and the shaft 1 does not move apparently in the motor.

The electromagnetic clutch coil may be energized by alternating current or direct current.

With such a structure, the energization of the motor coil O
N / OFF, forward / reverse ON / OFF, electromagnetic clutch ON /
If the OFF combination is selected, the following six functions can be selectively used.

(A) Motor non-energized, electromagnetic clutch OFF Motor shaft is free, and the shaft can be easily rotated forward and reverse.

(B) Motor energization, forward rotation, electromagnetic clutch OFF The rotor of the motor idles around the shaft, and no output torque appears on the shaft. The motor shaft is almost free.

(C) Motor energization, reverse rotation, electromagnetic clutch OFF The rotor of the motor idles around the shaft, and no output torque appears on the shaft. The motor shaft is almost free.

(D) Motor not energized, electromagnetic clutch on The rotor of the motor is connected to the shaft by an electromagnetic clutch.

Detent torque (non-excitation holding torque) appears on the motor shaft, and the forward and reverse rotation becomes heavy. It can be used as a brake.

(E) Motor energization, forward rotation, electromagnetic clutch ON The rotor of the motor rotates in combination with the shaft.

Normal motor normal rotation torque appears on the shaft.

(F) Motor energization, reverse rotation, electromagnetic clutch ON The rotor of the motor rotates in combination with the shaft.

Normal motor reverse torque appears on the shaft.

[0024]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention
-244748 ", and an object thereof is to reduce the shaft free torque in the above state (A).

Another object is that the operation is quiet and stable,
It is to provide an efficient electromagnetic clutch.

A larger capacitor type synchronous motor "PTM-2" having the same structure as the example shown in the prior art.
4H ”, the motor generated torque is 240
(G-cm), detent torque 60 (g-cm), and maximum shaft free torque 24 (g-cm). It has been found that in the case of a large motor, the magnetic force of the magnet is strong and it is difficult to reduce and stabilize the shaft free torque.

In the above-mentioned "PTM-24H" embodiment, when the electromagnetic clutch coil is AC100V specification and the power source AC100V is directly connected to the electromagnetic clutch coil, the attraction force of the clutch is weak and the slip resistance between the clutch pieces is weak. And the problem that noise is generated from the clutch during energization.

[0028]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides an electromagnetic clutch built-in motor according to claim 1 in which a rotating shaft supported by a stator and a bearing on the side of the stator so as not to move in the axial direction. A motor section including a rotor having a rotor, an output drive member rotatably supported on a rotary shaft, a first clutch piece fixed to the rotary shaft, and an output drive member fixed to the output drive member to face the first clutch piece. An electromagnetic clutch section comprising a clutch stator having an electromagnetic coil for attracting and coupling the second clutch piece to the installed second clutch piece and the first clutch piece; and
The second clutch piece is a ferromagnetic material having the same ring shape, in which a plurality of concave grooves extending in the radial direction at equal angular intervals are formed on the surfaces facing each other.

In the electromagnetic clutch built-in motor of claim 2,
In claim 1, the motor unit is a pulse motor using a DC power supply, and the electromagnetic clutch unit uses a DC power supply of the pulse motor.

In the electromagnetic clutch built-in motor of claim 3,
In claim 1, the motor unit is a synchronous motor using an AC power supply, and the electromagnetic clutch unit applies a voltage rectified from the AC power supply voltage to its electromagnetic coil.

In the electromagnetic clutch built-in motor of claim 4,
A coil spring is elastically interposed between the output drive member and the first clutch piece, and a stopper for preventing the output drive member from coming off is provided on the clutch stator side. It is characterized by being provided.

In the electromagnetic clutch built-in motor of claim 5,
A coil spring is elastically interposed between the output drive member and the first clutch piece, and a stopper for preventing the output drive member from coming off is provided on the rotary shaft side. It is characterized by being.

[0033]

There is a first clutch piece fixed to the motor output shaft and a second clutch piece opposed to the first clutch piece. An output drive member such as a pinion gear is fixed to the second clutch piece, and the output drive member has an inner diameter portion. Is movably fitted to the output shaft.

The first and second clutch pieces are not in contact with each other due to the elastic force of the spring when not energized, and are attracted against the elastic force of the spring by the magnetic force due to the energization of the exciting coil of the clutch. Join.

With respect to the output driving member, stoppers are provided at appropriate places to prevent the output driving member from falling off.

According to the research conducted by the present inventor, when an alternating current is applied to a coil of an electromagnetic clutch through a full-wave rectification bridge, a rectified voltage waveform and a current waveform flowing in the electromagnetic clutch coil are significantly different. Since the load of the full-wave rectified voltage is the electromagnetic induction coil, a current is connected and a smooth DC current of about 50% can be passed through the coil. It is also possible to eliminate the smoothing capacitor used for normal full-wave rectification. By applying the full-wave rectified voltage, it is possible to increase the attractive force of the clutch and reduce the noise.

The structure of the clutch is such that the two clutch pieces facing each other are formed in a ring shape, the facing surfaces are formed in the same shape and a plurality of grooves are provided, and a magnetically stable point is formed to realize a clutch having a strong coupling force that is hard to slip. .

[0038]

Embodiments of the present invention will be described below with reference to FIGS.

(First Embodiment) The motor with a built-in electromagnetic clutch shown in FIG. 1 is an embodiment of the present invention.
And a clutch portion B on the left side.

First, the motor section A will be described. The shaft 1 is supported by a front bearing 2 and a rear bearing 7. Further, the front bearing 2 is fixed to the flange 48, and the rear bearing 7 is fixed to the flange 6. The rotor (rotor) spacer 9 is press-fitted and fixed to the shaft 1, and the rotor (rotor core) 8 is adhesively fixed to the rotor spacer 9. The stator 21 that rotates the rotor 8 has a coil 16 and a coil 17.

In the clutch portion B, the first clutch piece 10 is press-fitted and fixed to the clutch spacer 29, and the clutch spacer 29 is press-fitted and fixed to the shaft 1. An output drive member 44 such as a pinion gear is press-fitted and fixed to the second clutch piece 11, and is fitted to the shaft 1 so as to be movable in the axial direction. The output drive member 44 contacts the housing 46 fixed to the flange 3 via the stopper 45 so as not to fall off. When the coil 34 of the electromagnetic clutch 31 is not energized, the first clutch piece 10 and the second clutch piece 11 are separated from each other by the elastic force of the return spring 12 and are in a non-contact state. Coil 34 of electromagnetic clutch 31
The electromagnetic clutch stator 22 and the first
A magnetic circuit is generated between the clutch piece 10 and the second clutch piece 11, the movable second clutch piece 11 is attracted to the first clutch piece, and as a result, the motor output torque is transmitted to the output drive member 44.

When the motor coils 16 and 17 and the coil 34 of the electromagnetic clutch 31 are not energized, the torque applied to the shaft is shaft free torque. In the conventional example, as shown in FIG. 9, when the shaft is rotated in this state, the return spring 12 reverses the second clutch piece 11 and the rotor spacer 9 holding the rotor 8 and the first clutch piece 10. It is pressed in the direction, and this becomes a frictional force to generate torque. In the present invention, as shown in FIG. 1, the motor portion A and the clutch portion B are mechanically separated, and the return spring 12 is press-fitted and fixed to the shaft 1 by the clutch spacer 29 and the output drive member 44. And are pressed in opposite directions, and as a result, a frictional force is mainly applied between the stopper 45 and the output drive member 44. Compared with the conventional example, the elastic force of the spring can be weaker and the friction points are mechanically limited, so the shaft free torque was suppressed to a small value.

FIG. 5 shows an embodiment of the shapes of the clutch pieces 10 and 11. First clutch piece 10 and second clutch piece 11
The shapes of the surfaces facing each other are the same.

The material of the clutch pieces 10 and 11 is a ferromagnetic material having a small residual magnetism, and a plurality of concave grooves 41 are provided in the ring shape at the same angular intervals in the radial direction. The width of the groove is constant and narrower than that of the fan-shaped portion 40.
The 0- and 11-shaped fan-shaped portions 40 are not fitted in the one concave groove 41.

In the clutch portion, a magnetic circuit is formed as shown in FIG.

If the magnetic circuit is constructed as shown in FIG. 6, the magnetic resistance can be reduced, and the second clutch piece 11 can be connected to the first clutch piece 1 against the return spring 12 with a small electric power.
It becomes possible to suck to the 0 side.

The structure of the electromagnetic clutch will be further described. When the clutch pieces 10 and 11 have the structure shown in FIG. 5 and the magnetic circuit is configured as shown in FIG. 6, the magnetic flux generated by energizing the coil 34 of the electromagnetic clutch 31 flows as shown by the arrow in FIG.

This magnetic flux enters from the outer circumference of the second clutch piece 11, passes through the facing surface of the fan-shaped portion 40, and escapes to the outer circumference of the first clutch piece 10. When the fan-shaped portions 40 of the clutch pieces 10 and 11 face each other (FIG. 7A), the magnetic resistance is lowest and the magnetic flux φ is maximum. The rotational slip prevention force (brake force) T _B at this time is T _F shown in FIG. 8, which is the product of the area of the fan surface, its friction coefficient, and the average turning radius of the clutch pieces 10, 11. This value is low.

On the other hand, the clutch pieces 10 and 11 shown in FIG.
By providing the concave groove 41 shown by, it is possible to utilize the magnetic stability restoring force similar to the operating principle of the variable reluctance type pulse motor. In FIG. 7A, this magnetic stability restoring force is zero. When external force torque is applied from the state of FIG. 7A and one of the clutch pieces 10 and 11 is displaced in the rotational direction, the torque T _M due to the magnetic stabilizing force shown in FIG. 8 is generated. A clutch having four grooves as shown in FIG. 5, in which the concave groove 41 and the concave groove 41 of the clutch pieces 10 and 11, that is, the fan-shaped portion 40 and the fan-shaped portion 40 are completely opposed to each other at an angle of 0 degree. In the case of the pieces 10 and 11, the torque T _B due to the magnetic stable restoring force becomes maximum at the angle shifted by 45 degrees shown in FIG. 7 (B).

In the example of the outer diameter of the clutch piece of 20 (mm), the brake torque without the groove was 100 (g-cm), and when the four grooves were provided, it could be 350 (g-cm).

Next, the power source for the electromagnetic clutch will be described.

A DC power supply is suitable for this power supply. Therefore, if the motor unit A of the electromagnetic clutch built-in motor is a motor that uses a DC power source such as a pulse motor, the DC power source can be used for the electromagnetic clutch. However, when the motor unit A is an AC motor such as a synchronous motor, a suitable DC power supply is produced based on the AC power supply. One example is shown in FIG. In FIG. 3, the AC power supply common to the motor unit A is rectified by the diode bridge 38 via the operation switch 33 for turning on / off the supply to the electromagnetic clutch, and the rectified voltage is applied to the coil 34 of the electromagnetic clutch 31.

According to the research conducted by the present inventor, the connection shown in FIG.
It was found that the voltage waveform after rectification by the diode bridge 38 and the waveform of the current flowing through the coil 34 of the electromagnetic clutch 31 are significantly different. FIG. 4B shows a voltage waveform after rectification by the diode bridge 38, and FIG. 4A shows a current waveform flowing in the coil 34 of the electromagnetic clutch 31.

In FIG. 3, it was found that a smooth DC current of about 50% flows as the coil current because the load of the full-wave rectified voltage is the electromagnetic induction coil. In the present invention, it is possible to eliminate the smoothing capacitor used for normal full-wave rectification.

By taking the above measures, it is possible to prevent the AC noise and vibration generated from the electromagnetic clutch and improve the magnetic attraction force of the clutch.

(Second Embodiment) FIG. 2 shows a second embodiment of the electromagnetic clutch built-in motor.

Basically, the structure is the same as that of the electromagnetic clutch built-in motor of the first embodiment, and the parts to which the same numbers are given have the same structure and function, so that the description thereof will be omitted.

In FIG. 2, the output drive member 44 is connected to the shaft 1
It is fitted in the shaft 1 so as to be movable in the axial direction, and a stopper 47 is press-fitted and fixed to the shaft 1 to prevent the output drive member 44 from coming off. This point is different from the embodiment of FIG.

[0059]

As described above, by constructing the electromagnetic clutch built-in motor, the shaft free torque when the clutch is off can be suppressed to a few g-cm when the motor is not energized.

Further, the attraction force of the electromagnetic clutch can be improved, and the rotation slip prevention force between the clutch pieces can be improved.

It is possible to provide a low-priced electromagnetic clutch built-in motor.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional side view of a motor with a built-in electromagnetic clutch according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional side view of a motor with a built-in electromagnetic clutch according to a second embodiment of the present invention.

FIG. 3 is a circuit diagram of a power supply unit for a coil of an electromagnetic clutch unit.

FIG. 4 shows a current waveform (A) flowing in a coil of the electromagnetic clutch and a voltage waveform after diode bridge rectification.

FIG. 5 is a perspective view of an example of the shape of a clutch piece.

FIG. 6 is a magnetic circuit diagram of an electromagnetic clutch unit.

FIG. 7 is a cross-sectional view of a clutch piece in a suctioned state.

FIG. 8 is an angle dependency of a rotation slip prevention force in a suction state of a clutch piece.

FIG. 9 is a partial cross-sectional side view of a conventional electromagnetic clutch built-in motor using a capacitor type synchronous motor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shaft 2 ... Front bearing 3,6,48 ... Flange 4 ... Stator 5,31 ... Electromagnetic clutch 7 ... Rear bearing 8 ... Rotor 9 ... Rotor spacer 10 ... 1st clutch piece 11 ... 2nd clutch piece 12 ... Returning spring 13 ... Gap (rotor-stator) 14 ... Gap (shaft-rotor spacer) 15 ... Gap (between clutch pieces) 16, 17 ... Coil (for motor) 20, 34 ... Coil (electromagnetic) Clutch) 21 ... Stator (for motor) 22 ... Stator (for electromagnetic clutch) 29 ... Clutch spacer 44 ... Output drive member 45, 47 ...
Stopper 46 ... Housing

Claims (5)

[Claims] 1. A motor unit comprising a rotor and a rotor having a rotating shaft axially immovably supported by a bearing on the side of the stator, and an output drive member supported by the rotating shaft so as to be thrust movable. A first clutch piece fixed to the rotating shaft, and a second clutch piece fixed to the output driving member and opposed to the first clutch piece.
An electromagnetic clutch unit including a clutch stator having an electromagnetic coil for attracting and coupling the second clutch piece to the clutch piece and the first clutch piece; and the first and second clutch pieces of the electromagnetic clutch section. An electromagnetic clutch built-in motor, which is a ferromagnetic material having the same ring shape, in which a plurality of concave grooves extending in the radial direction at equal angular intervals are formed on mutually opposing surfaces. 2. The built-in electromagnetic clutch according to claim 1, wherein the motor section is a pulse motor using a DC power source, and the electromagnetic clutch section uses a DC power source of the pulse motor. motor. 3. The motor unit is a synchronous motor using an AC power supply, and the electromagnetic clutch unit applies a voltage rectified from the AC power supply voltage to its electromagnetic coil. The electromagnetic clutch built-in motor according to claim 1. 4. A coil spring is elastically interposed between the output drive member and the first clutch piece, and a stopper for retaining the output drive member is provided on the clutch stator side. The electromagnetic clutch built-in motor according to claim 1 or claim 2 or 3, characterized in that. 5. A coil spring is elastically interposed between the output drive member and the first clutch piece, and a stopper for preventing the output drive member from coming off is provided on the rotary shaft side. The motor with a built-in electromagnetic clutch according to claim 1 or claims 2 and 3.