JP3740470B2 - DC brushless motor with reduction gear - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a DC brushless motor with a reduction gear.
[0002]
[Prior art]
The DC brushless motor has an advantage that it has a larger starting torque than an induction motor and can withstand frequent starting and stopping. Also, generally higher accuracy can be obtained compared to a structure in which the induction motor is controlled and driven by a so-called inverter. Therefore, it is frequently used in various fields in recent years.
[0003]
The DC brushless motor is generally controlled and driven by a controller called a driver. This driver is a pure electric part, and for the purpose of centrally driving and controlling many motor bodies in the factory at one location, it is provided at a position away from the conventional motor body, and each is connected by a cable. The structure which connects with the motor main body of this was employ | adopted.
[0004]
However, in recent years, a layout that can drive and control the machines in the factory independently is required due to the demand for production of a small variety of products. Therefore, it is better to drive and control each machine independently at each location. It has become a convenient situation.
[0005]
From this point of view, in recent years, as described in, for example, Non-Patent Document 1 (see FIG. 2), the motor body 2 and its driver 4 are integrated so that the motor body 2 can be driven and controlled by itself. A driver-integrated DC brushless motor 6 is also proposed.
[0006]
[Non-Patent Document 1]
Matsushita Electric Industrial Co., Ltd., Motor Company, catalog of brushless motor with integrated circuit (September 2002)
[0007]
[Problems to be solved by the invention]
For example, in a DC brushless motor for driving a shutter or an electric curtain, or a DC brushless motor for driving an elevating device, the driven object must be maintained in a stopped state at an arbitrary position. In such an application, a mechanical brake mechanism for maintaining the driven object in a stopped state is essential when the vehicle is stopped, that is, when the power is turned off.
[0008]
In addition, when a DC brushless motor is used for such an application, the rotational speed is too high as it is, and it is often necessary to attach a reduction gear.
[0009]
When a mechanical brake mechanism is attached to a driver-integrated DC brushless motor, for example, when the mechanical brake mechanism is attached to the output shaft side of the motor body, the mechanical brake mechanism results in a gap between the motor body and the speed reducer. As a result, the maintenance of the mechanical brake mechanism becomes difficult. In addition, when the mechanical brake mechanism is to be installed on the side opposite to the motor body of the driver, it is necessary to form a configuration in which the motor shaft of the motor body passes through the center of the driver, which makes it difficult to design the driver. Etc. occur.
[0010]
The present invention has been made in view of such a conventional situation. In particular, in a DC brushless motor integrated with a driver, the driver, the motor body, the mechanical brake mechanism, and the reduction gear are technically the most. The problem is to provide a structure for rational arrangement.
[0011]
[Means for Solving the Problems]
The present invention provides a DC brushless motor with a speed reducer in which a speed reducer is integrally connected to a motor body of a DC brushless motor controlled by a driver, and includes a mechanical brake mechanism capable of applying braking to rotation of a motor shaft, The above problems are solved by assembling the driver, the mechanical brake mechanism, the motor main body, and the input shaft of the speed reducer on the same axis in this order.
[0012]
In the present invention, the driver, the mechanical brake mechanism, the motor main body, and the speed reducer (input shaft thereof) are incorporated in this order on the same axis, so that it is not necessary for the driver to penetrate the motor shaft of the motor main body. Further, since the driver is integrated with the motor body, there is no need to provide a separate driver (controller) outside, and there is no need to attach a cable between them.
[0013]
Further, since the mechanical brake mechanism is sandwiched between the driver and the motor body, the extension of the motor shaft of the motor body is minimal, and the driver is decelerated (oil etc. is present). It is easier than removing the machine. That is, for example, it is possible to prevent the occurrence of a problem that the driver is sandwiched between the motor body and the speed reducer and the maintenance becomes difficult.
[0014]
If the driver is provided with a driver cover on the mechanical brake mechanism side, and the driver cover also serves as a cover of the brake mechanism, the driver is attached with a cover when performing maintenance of the mechanical brake mechanism ( It can be removed reliably (in an almost completely independent state). Further, the mechanical brake mechanism can be exposed as it is by removing the driver, and the maintenance of the mechanical brake mechanism can be started immediately.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, examples of embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
FIG. 1 shows an example of a DC brushless motor with a reduction gear to which an embodiment of the present invention is applied.
[0017]
The DC brushless motor 10 with a reduction gear includes a driver 12, a mechanical brake mechanism 14, and a motor body 16 on the same axis L in this order, and further includes a reduction gear 18 on the same axis L in succession.
[0018]
The driver 12 converts single-layer or three-layer alternating current (AC) into direct current (DC) and generates electric power for controlling and driving the motor body 16. The driver 12 has a built-in regenerative brake circuit (not shown) and is designed to recover braking energy generated during braking. Note that the braking of the motor main body 16 by the function of the driver 12 is merely to reduce the rotational speed during rotation, and has no function of maintaining braking during stoppage. Since the configuration of the driver 12 itself is not particularly different from the conventional one, detailed illustration and specific description are omitted.
[0019]
The mechanical brake mechanism 14 can mechanically apply braking to the rotation of the motor body 16 even when the power is turned off. A motor shaft 20 of the motor body 16 extends and is inserted into the central portion of the mechanical brake mechanism 14 so that the rotating disk (first friction plate) 22 can rotate integrally with the motor shaft 20. ing. The motor cover 24 is fixed to the casing main body 28 via bolts 26. A fixed disk (second friction plate) 30 is fixed on the motor cover 24 with bolts 32 so as to face the rotating disk 22.
[0020]
The mechanical brake mechanism 14 maintains a state (braking state) in which the rotating disk 22 and the fixed disk 30 are pressed by a spring (not shown) when the power is turned off, including when the power is turned off, and an electromagnetic force that can overcome this pressing force during operation. Is generated to form a released state. The generated electromagnetic force can be controlled by adjusting the release current at this time, and the applied braking force can be adjusted.
[0021]
The motor body 16 is brushless and can be driven by direct current (DC). All the control relating to the rotation of the motor body 16 is received from the driver 12 side.
[0022]
In this example, the reduction gear 18 has a swinging intermeshing planetary gear structure. That is, the motor shaft 20 of the motor body 16 extends to the inside of the speed reducer 18 and functions as an input shaft (40) of the speed reducer 18 as it is. An external gear 44 is incorporated on the outer periphery of the input shaft (40) via an eccentric body 42 so as to be able to swing and rotate, and is internally meshed with an internal gear 46 in a fixed state. The external gear 44 and the internal gear 46 have a slight difference in the number of teeth of about 1 to 3. In the speed reducer 18, the rotation component of the external gear 44 is transmitted to the carrier 50 via the inner pin 48, and the power is extracted from the output shaft 52 integrated with the carrier 50.
[0023]
The load side cover 60 of the motor body 16 also serves as the input side cover of the speed reducer 18 and is formed integrally with the casing body 28. The load side cover 64 of the speed reducer 18 is fixed to the casing main body 28 with bolts 68 together with the speed reducer casing 66 integrated with the internal gear 46.
[0024]
As is clear from FIG. 1, the driver 12 includes a driver cover 70 on the mechanical brake mechanism 14 side, and the driver cover 70 also serves as a cover for the mechanical brake mechanism 14. The driver cover 70 is fixed and coupled to the flange portion 74 of the casing main body 28 via bolts 72. Electrical connection between the driver 12 side and the mechanical brake mechanism 14 and the motor main body 16 side is made through cables 80 and 82. The cables 80 and 82 are connected through a detachable socket 84 in consideration of convenience during separation. Note that the socket is not particularly necessary when the cable has a margin.
[0025]
Next, the operation of this embodiment will be described.
[0026]
The motor main body 16 is controlled in its rotational state by the DC drive current controlled by the driver 12 (including regenerative braking). While the motor shaft 20 is rotating, the mechanical brake mechanism 14 is basically maintained in the released state. The rotation of the motor shaft 20 is directly transmitted to the reduction gear 18 side as the rotation of the input shaft (40) of the reduction gear 18, and is output from the output shaft 52 after being decelerated to a predetermined reduction ratio by a known action.
[0027]
Here, in order to maintain the motor shaft 20 in a stopped state while the motor shaft 20 is stopped, the release current of the mechanical brake mechanism 14 is turned OFF, and the rotating disk 22 and the fixed disk 30 are frictionally joined by the urging force of the spring. As a result, this braking state can be maintained without particularly consuming electric power. Therefore, for example, when a device such as a shutter, an electric curtain, various lifting devices, etc. that falls as it is due to gravity is used as a driven target, the driven target can be fixed at an arbitrary position. Become.
[0028]
In this embodiment, since the driver 12 is integrally coupled to the motor body 16, a separate driver (controller) is not required, and a cable for electrically connecting them is not required. Further, since the mechanical brake mechanism 14 is disposed between the motor body 16 and the driver 12, the extension of the motor shaft 20 can be minimized, and the motor shaft 20 does not pass through the center of the driver 12. Twelve designs are also easy.
[0029]
In addition, the driver 12 can be removed together with the driver cover 70 by removing the bolt 72. This removal is very simple compared to, for example, removing the speed reducer 18 (with oil). Further, since the cables 80 and 82 are detachably connected via the socket 84, the cables 80 and 82 of the driver 12 can be easily separated and reconnected.
[0030]
Further, since the driver cover 70 also serves as the cover of the mechanical brake mechanism 14, the mechanical brake mechanism 14 is exposed as it is when the driver 12 is removed, so that the maintenance of the mechanical brake mechanism 14 is easy.
[0031]
On the other hand, since the mechanical brake mechanism 14 does not exist between the motor main body 16 and the speed reducer 18, the configuration in which the motor shaft 20 directly becomes the input shaft (40) of the speed reducer 18 can be easily realized while maintaining high rigidity. be able to.
[0032]
With the above configuration, the rigidity of the four components, that is, the driver 12, the mechanical brake mechanism 14, the motor body 16, and the speed reducer 18 is highly rigid while preventing the axial length of the DC brushless motor 10 with the speed reducer from increasing. Can be reasonably linked.
[0033]
In the above embodiment, a swinging intermeshing planetary gear type speed reducer is applied as the speed reducer 18, but the present invention is not particularly limited in terms of the specific configuration of the speed reducer.
[0034]
Further, the configuration of the mechanical brake mechanism 14 is not particularly limited to the above configuration.
[0035]
【The invention's effect】
According to the present invention, particularly regarding a DC brushless motor with a speed reducer equipped with a driver and a mechanical brake mechanism, each element is rationally prevented while preventing occurrence of problems such as occurrence of problems and increase in axial length as much as possible. The excellent effect of being able to be connected and integrated with each other is obtained.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a configuration example of a DC brushless motor with a reduction gear to which the present invention is applied. FIG. 2 is a longitudinal sectional view showing a configuration example of a conventional DC brushless motor integrated with a driver.
DESCRIPTION OF SYMBOLS 10 ... DC brushless motor 12 with a reduction gear ... Driver 14 ... Mechanical brake mechanism 16 ... Motor main body 18 ... Reduction gear 20 ... Motor shaft 22 ... Rotary disk 24 ... Motor cover 28 ... Casing main body 30 ... Fixed disk 40 ... Input shaft (motor) axis)
42 ... Eccentric body 44 ... External gear 46 ... Internal gear 48 ... Inner pin 50 ... Carrier 52 ... Output shaft 60 ... Motor body load side cover 64 ... Reducer load side cover 66 ... Reducer casing 70 ... Driver cover 80, 82 ... cable 84 ... socket L ... axis

Claims (2)

In a DC brushless motor with a reduction gear in which a reduction gear is integrally connected to a motor body of a DC brushless motor controlled by a driver,
A mechanical brake mechanism capable of applying braking to the rotation of the motor shaft of the motor body;
A DC brushless motor with a reduction gear, wherein the driver, the mechanical brake mechanism, the motor body, and the input shaft of the reduction gear are assembled in this order on the same axis. In claim 1,
The DC brushless motor with a speed reducer, wherein the driver includes a driver cover on the mechanical brake mechanism side, and the driver cover also serves as a cover of the mechanical brake mechanism.

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