JP2004274884A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor which combines measures for insulation and measures to heat and is easy to be made compact in size. <P>SOLUTION: The section between an insulating cap 19 and the coil end of a winding 11b is impregnated with vanish 18 for sticking, and a high-heat-conductive elastic body 20 is arranged between the insulating cap 19 and a bracket 15 on the side of an output shaft, and the bracket 15 is fixed to a frame 17, whereupon the high-heat-conductive elastic body 20 is pressed and transformed. However, it sticks fast to the insulating cap 19, the bracket 15 and the frame 17 by the reaction of the elastic body, and it can transmit the heat generated by the winding to the bracket 15 and the frame 17, thereby radiating it. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cooling structure for a high-output motor used for industrial equipment.
[0002]
[Prior art]
In recent years, motors for industrial applications have been required to be small, high-performance, and low-cost. High-performance rare-earth magnets have been used for rotors, and stators have been downsized by increasing the density of windings using split cores. Therefore, insulation measures and heat measures are needed.
[0003]
Since heat generated from the motor winding has a bad influence on the performance of the sensor and the motor, various measures have been taken.
[0004]
For example, in a molded motor in which a stator around which a coil is wound is resin-molded, an outer peripheral portion of a bracket and an outer peripheral portion of a stator core are brought into contact with each other at an axial end face, so that heat generated by winding is efficiently transmitted from the outer periphery of the stator core to the bracket. The heat is transmitted well, and this heat is released to the outside air (for example, see Patent Document 1).
[0005]
Further, a high heat conductive resin is filled between the end face of the winding wound on the stator core and a bracket or a frame supporting the rotor via a bearing to radiate heat (for example, see Patent Document 2). ).
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 7-163082 [Patent Document 2]
JP-A-5-328686
[Problems to be solved by the invention]
However, when the resin molding is performed as described above, not only is the cost of the mold and equipment required, but also at the time of integral molding of the core and the winding, the winding at the outer peripheral portion moves due to the flow and pressure of the molding resin and has a poor withstand pressure. There is a problem that quality is not stable due to the occurrence of such problems.
[0008]
On the other hand, when a heat conductive resin is used, there is a problem that if the filling amount is large, it protrudes to the inner peripheral side, and if the filling amount is small, heat transfer is not sufficiently exhibited.
[0009]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an inexpensive motor that has both insulation measures and heat measures and that can be easily miniaturized.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a stator having a winding on a stator core, a metal frame covering an outer peripheral portion of the stator core, and bearings disposed at both ends of the frame. A metal bracket that rotatably supports the rotor via the coil, an insulating cap disposed between the coil end of the output shaft side winding and the output shaft side bracket, and a varnish filled between the coil end and the insulating cap. And a high thermal conductive elastic body disposed between the insulating cap and the bracket.
[0011]
A stator provided with a winding on a stator core; a metal bracket disposed at both ends of the stator for rotatably supporting a rotor via bearings; and a coil end of an output shaft side winding. And an insulating cap disposed between the bracket and the output shaft side, a varnish filled between the coil end and the insulating cap, and a high thermal conductive elastic body disposed between the insulating cap and the bracket.
[0012]
According to this configuration, the high thermal conductive elastic body is pressed and sandwiched between the insulating cap and the bracket, and is brought into close contact with each other, thereby making it possible to take measures against insulation and heat radiation.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
In order to solve the above-mentioned problem, the motor according to claim 1 or 2 ensures insulation of a coil end by an insulating cap, and radiates heat from a winding to a varnish, an insulating cap, a high thermal conductive elastic body, and a bracket. (Or via a frame) to drive equipment and outside air to dissipate heat and suppress the motor temperature rise.
[0014]
Further, in addition to the above, the motor according to the third aspect is formed by applying an adhesive to the laminating surface and firmly forming the same, thereby improving the adhesion of the stator core and further promoting the flow of heat in the axial direction. Can be done.
[0015]
Further, the motor according to claim 4 is provided with a sensor such as an encoder which dislikes heat on the side opposite to the output shaft in addition to the above, so that heat is positively guided to the output shaft side and heat conduction to the sensor side is performed. Can be suppressed.
[0016]
【Example】
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0017]
In FIG. 1, reference numeral 11 denotes a stator, and windings 11b are concentratedly wound around teeth of a stator core 11a. 12 is a rotor, 13 and 14 are bearings, 15 and 16 are aluminum brackets, and 17 is a frame, which is shrunk on the outer periphery of the stator 11. Reference numeral 18 denotes a varnish, 19 denotes an insulating cap, and 20 denotes a high thermal conductive elastic body.
[0018]
The insulating cap 19 is provided to reliably insulate the coil end of the winding 11b from the output shaft side bracket 15, and is preferably made of resin and has a donut shape. The inside and the outside of the donut shape are folded back to the winding side so that the donut shape can be fitted to the end of the winding 11b to facilitate mounting.
[0019]
By providing the insulating cap 19, it is not necessary to secure an unnecessarily long insulation distance between the coil end of the winding 11b and the bracket 15, and the motor can be downsized in the axial direction.
[0020]
Heat-curing is applied to the stator with windings for two purposes to prevent the windings from vibrating when a large current is applied and failing to withstand pressure, and to fill the gap between the windings and improve heat conduction. The winding is hardened by impregnating with a conductive varnish.
[0021]
In the present invention, the stator 11, the varnish 18, and the insulating cap 19 are integrated by mounting the insulating cap before the varnish impregnating step, impregnating and curing the varnish 18 with the insulating cap 19 facing downward. You can make a unit.
[0022]
This is as if the windings were formed by resin molding, but there is no need to change ordinary processes and materials other than the insulating cap 19. Moreover, since it is impregnated with varnish, there is no need for a molding machine or a mold unlike a resin mold, and there is no need to worry about poor pressure resistance, so that it can be realized at low cost. Note that an insulating cap may also be provided on the coil end on the side opposite to the output shaft.
[0023]
On the other hand, as a material of the high thermal conductive elastic body 20, silicon rubber is suitable and is formed in advance so as to conform to the insulating cap 19. At this time, the thickness of the high thermal conductive elastic body 20 is set slightly larger than the gap size (design value) between the insulating cap 19 and the bracket 15, and the outer diameter is set slightly smaller than the inner diameter of the frame 17.
[0024]
When the bracket 15 is fixed to the frame 17, the high thermal conductive elastic body 20 is pressed and deformed, but the high thermal conductive elastic body 20 comes into close contact with the insulating cap 19, the bracket 15 and the frame 17 due to the reaction force of the elastic body.
[0025]
Thus, the heat generated by the winding 11b is transmitted to the bracket 15 and the frame 17 via the varnish 18, the insulating cap 19, and the high thermal conductive elastic body 20, and is attached to the atmosphere or from the outer surfaces of the bracket 15 and the frame 17. Dissipated to equipment.
[0026]
By the way, if the stator core 11a in which the lamination surface of the core is fixedly formed with an adhesive is used, the heat transfer in the axial direction is improved, and a further heat radiation effect can be expected.
[0027]
The high thermal conductive elastic body 20 is always disposed between the insulating cap 19 and the coil end of the output shaft side winding 11b. However, when the sensor 21 such as an encoder is provided on the non-output shaft side, the If the high thermal conductive elastic body 20 is provided between the side bracket 16 and the coil end on the side opposite to the output shaft, heat will be transmitted to the sensor 21 side, so it is better not to implement this.
[0028]
According to the present example, the temperature of the windings could be reduced by about 4 degrees with a 100 W motor.
[0029]
Although not shown, the present embodiment can be similarly implemented by directly fixing the bracket to the stator core without using the frame of the present embodiment, or by integrally forming the frame and the bracket.
[0030]
Further, since insulation between the coil end and the bracket can be ensured by the insulating cap, the high thermal conductive elastic body does not need to be limited to an insulator, and may be mixed with metal powder.
[0031]
【The invention's effect】
As is apparent from the above embodiment, according to the present invention, the varnish impregnation using the insulating cap and the effective arrangement of the high thermal conductive elastic body enable measures against insulation in the axial direction and measures against heat radiation. Therefore, it is not necessary to secure an insulation distance between the coil end and the bracket more than necessary, so that the size can be reduced.
[0032]
Further, in a motor having a sensor on the side opposite to the output shaft, heat is positively transmitted to the side of the output shaft, so that heat conduction to the sensor on the side opposite to the output shaft can be suppressed.
[0033]
Therefore, it is possible to provide a small and inexpensive motor having both insulation measures and heat measures.
[Brief description of the drawings]
FIG. 1 is a sectional view of a motor according to an embodiment of the present invention.
11 Stator 11a Stator core 11b Winding 15 Bracket (output shaft side)
17 Frame 18 Varnish 19 Insulating cap 20 High thermal conductive elastic body 21 Sensor

Claims (4)

A stator having a winding on a stator core, a metal frame covering an outer peripheral portion of the stator core, and a metal frame disposed at both ends of the frame and rotatably supporting a rotor via bearings. Bracket, an insulating cap disposed between the coil end of the output shaft side winding and the output shaft side bracket, a varnish filled between the coil end and the insulating cap, and a high heat disposed between the insulating cap and the bracket. A motor comprising a conductive elastic body, wherein the high thermal conductive elastic body is pressed and sandwiched between the insulating cap and the bracket so as to be in close contact with each other. A stator having a winding on a stator core; a metal bracket disposed at both ends of the stator to rotatably support a rotor via bearings; and a coil end and an output of an output shaft side winding. An insulating cap provided between the shaft-side brackets, a varnish filled between the coil end and the insulating cap, and a high heat conductive elastic body provided between the insulating cap and the bracket; Is pressed and held tightly between the insulating cap and the bracket. The motor according to claim 1 or 2, wherein the stator core is formed by applying an adhesive to a lamination surface and fixing the stator core. The motor according to any one of claims 1 to 3, wherein a sensor such as an encoder is provided on a side opposite to the output shaft.

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