JPH06284632A - Belt driven motor - Google Patents

Abstract

PURPOSE:To avoid difficulties in the centering work of a third bearing by decreasing the diameter of a bearing on the operating side and thereby decreasing the value of d.n thus allowing grease lubrication even for a high belt load. CONSTITUTION:A rotor 3 is secured to a shaft 22 born by an operating side bearing A and an opposite side bearing B and a stator 5 is secured to a frame 4. A belt 7 is entrained about an overhanging pulley 6 at an end of the shaft 22 projecting from a bracket 1a on the operating side and the shaft 22 is born by a third bearing C at the other end thereof. A bottomed cylindrical pulley frame 23 is fixed to the outside of the bracket 1a while being split into a bearing box 23c, a bottom part 23a, and a cylindrical part 23b so that it can be dismantled. A belt hole 24 is made in the cylindrical part 23b. When the belt 7 is taken out, the bottom part 23a is removed from the cylindrical part 23b and the bearing box 23c and the rounded end part of the belt 7 is separated from the bearing box 23c and then drawn out through the belt hole 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor for driving a belt, in which a pulley is mounted on the driving side of a shaft, which can reduce the bearing load of a driving side bearing.

[0002]

2. Description of the Related Art FIG. 4 is a half sectional view of a conventional example 1, FIG. 5 is a half sectional view of a driving side bearing device of a conventional example 2, and FIG. In the following description, the components denoted by the same reference numerals in each figure have approximately the same function, and duplicated explanation may be omitted. In FIG. 4, a pair of brackets 1a of the electric motor,
A rotor 3 is fixed to a shaft 2 supported by a driving side bearing A and a non-driving side bearing B attached to 1b, and a tubular stator 5 is fixed to a frame 4 supporting both brackets. Either of the brackets 1a and 1b may be integrated with the frame 4.
A pulley 6 is attached to the end portion of the shaft 2 protruding from the bracket 1a on the driving side by overhanging, and a belt 7 such as a V belt is wound around the pulley 6. The belt load by the belt 7 is P. With a small electric motor, the d / n value of the bearing (bearing inner diameter dm
If m × rotational speed nrpm) is about 200 to 300,000 or less, a grease-lubricated rolling bearing is used as the running-side bearing A. When the d · n value exceeds this value, the running side bearing A is lubricated with oil.

Conventional example 2 shown in FIG. 5 is an oil-lubricated operating side bearing device. In the figure, a pair of oil tanks 92a and 92b having a plurality of labyrinths 91 are oil-tightly provided in the front and rear in the axial direction of the operation side bearing A that supports the shaft 2 with respect to the bracket 1a, and store an appropriate amount of oil 93. Although omitted from the description, other components and processes are shown or not shown, and the oil-lubricated bearing structure is much more complicated and expensive than the grease-lubricated bearing structure, and requires a lot of maintenance.

Prior art example 3 shown in FIG. 6 uses grease lubrication by reducing the load on the operating side bearing by the third bearing and keeping the d · n value below the limit. In the figure, a bearing stand 96 to which the third bearing C at the end of the extended shaft 95 is attached
Are installed on a common base 97 with the electric motor. Since the belt load P is also borne by the third bearing C, the bearing load of the driving side bearing A is significantly reduced. However, the common base 97 has a high rigidity and a large size. Further, it is necessary to center three bearings, and a considerable amount of skill is required for work such as bracing an appropriate number of thin plates 98 at four corners between the bearing stand 96 and the common base 97. If the centering work is improper, the electric motor may be damaged within a few days after installation.

[0005]

In the above-mentioned conventional example, even if the electric motor is small, the diameter of the driven pulley may be considerably larger than the diameter of the pulley 6 so that the reduction ratio and the torque are high. Then, the belt load P of the pulley 6
Becomes larger and the bearing load of the operating side bearing A becomes larger.
For this reason, the diameter of the shaft 2 and the bearing A on the operating side becomes large,
Since the limit d / n value is exceeded, there is no choice but to use the oil lubrication method or the third bearing method. If the electric motor becomes large, the oil lubrication method or the third bearing method is naturally used. However, the oil lubrication system has a complicated structure and is expensive, and requires maintenance. In addition, the third bearing system requires a large common base,
Skilled work is required for centering the three bearings.

An object of the present invention is that even if the belt load or the electric motor is increased, the diameter of the bearing on the driving side is small and the d / n value is small, and grease lubrication is possible, which makes it difficult to center the third bearing. An object of the present invention is to provide an electric motor for driving a belt that can avoid the above.

[0007]

According to another aspect of the present invention, there is provided a belt driving electric motor, in which a rotor is fixed to a shaft supported by a driving side bearing and a non-driving side bearing mounted on a pair of brackets to support both brackets. In a belt-driving electric motor in which a tubular stator is fixed to a frame, a pulley is attached to the shaft protruding from the driving-side bracket, and a belt is wound around the shaft, a bottom portion and a tubular portion are provided outside the driving-side bracket. And a bottomed cylindrical pulley frame, which is composed of and is extended, and the pulley frame is divided into a bearing box having a third bearing and an outer periphery thereof by one or more desired dividing portions so that the pulley frame can be attached and detached. A belt hole is opened in the pulley frame at the position where the shaft end is supported, and the end portion of the shaft is supported by the third bearing.

In the belt driving electric motor of the invention 2, a rotor is fixed to a shaft supported by a driving side bearing and an anti-driving side bearing mounted on a pair of brackets, and a cylindrical frame is mounted on a frame supporting the both brackets. In a belt driving electric motor that fixes a stator, attaches a pulley to the shaft protruding from the operating side bracket, and winds a belt around the operating side bracket, a bottomed cylinder having a bottom portion and a tubular portion outside the operating side bracket. -Shaped pulley frame is extended, and the pulley frame is divided into a bearing box having a third bearing and an outer periphery thereof by one or more desired dividing portions so as to be detachable, and the pulley frame at a position corresponding to the belt. A belt hole is formed in the end of the pulley and the end of the pulley is supported by the third bearing. It should be noted that, instead of the invention 1 supporting the end portion of the shaft by the third bearing, the invention 2 is different in that the end portion of the pulley is supported by the third bearing.

A third aspect of the present invention is the invention of the first or second aspect, in which the dividing portion is between the bearing box and the bottom portion and between the bottom portion and the tubular portion. A fourth aspect of the present invention is the same as the third aspect, wherein the dividing portion is between the driving-side bracket and the pulley frame. A fifth aspect of the present invention is the first or second aspect of the present invention, in which the split portion is between the bearing box and the bottom portion and between the driving-side bracket and the pulley frame. A sixth aspect of the invention is the invention of the first or second aspect, in which the dividing portion is provided between the bottom portion and the tubular portion,
It is between the driving-side bracket and the pulley frame.

[0010]

According to the first aspect of the present invention, since the end portion of the shaft, which is mounted by overhanging the pulley on the outside of the operating side bearing, is supported by the third bearing, the bearing load of the operating side bearing due to the belt load and the diameter of the shaft are small. Become. For this reason, the running-side bearing is downsized, the d · n value of the bearing is reduced, and grease lubrication is sufficient for oil lubrication. The pulley frame to which the third bearing is mounted can be lathe-processed and has high accuracy, so centering work is eliminated. During use, the belt wound around the pulley and the driven pulley passes through the belt hole. To take out the belt, the pulley frame is removed at the dividing portion, the rounded end of the belt is pulled around around the shaft end, and then pulled out from the belt hole. When wrapping the belt, the procedure is reversed.

According to the operation of the invention 2, since the end portion of the pulley that overhangs outside the operating side bearing is supported by the third bearing,
The operation is the same as that of Invention 1. According to the third aspect of the present invention, when only the belt is replaced, the bottom portion is detached from the shaft by dividing it at two locations, so that it is not necessary to disassemble the bearing box and the driving side bearing from the shaft. According to the fourth aspect of the invention, since the tubular portion can be individually removed, the belt can be replaced more easily. According to the invention 5 or the invention 6, it is a little heavy work because it is divided at two places and the tubular part is also removed together, but when only the belt is replaced, the work of disassembling the bearing box and the operating side bearing from the shaft is required. Not.

[0012]

1 is a sectional view of one side of Example 1, FIG. 2 is a sectional view of FIG. 1 taken along the line AA, and FIG. 3 is a sectional view of one side of Example 2. 2 is applied to FIG. 1 corresponds to Invention 1, and FIG. 3 corresponds to Invention 2. 1 and 2, a rotor 3 is fixed to a shaft 22 supported by a driving side bearing A and a non-driving side bearing B mounted on a pair of brackets 1a and 1b of an electric motor, and is attached to a frame 4 supporting both brackets. The cylindrical stator 5 is fixed. Either of the brackets 1a and 1b may be integrated with the frame 4. The pulley 6 is attached to the end of the shaft 22 protruding from the driving side bracket 1a by overhanging, and a belt 7 such as a V belt is wound around the pulley 6.

A feature of the embodiment is that a bottomed cylindrical pulley frame 23 composed of a bottom portion 23a and a cylindrical portion 23b is extended outside the driving side bracket 1a, and the pulley frame 23 is provided with a third bearing C.
The bearing box 23c provided with and the outer periphery thereof are divided at desired one or more dividing portions D so as to be detachable. A belt hole 24 is formed in the pulley frame 23 at a position corresponding to the belt 7, and the end of the shaft 22 is supported by the third bearing C.

As a concrete example of the divided portion D, D is a bearing box 23.
D1 between c and the bottom portion 23a, and the bottom portion 23a and the tubular portion 2
3b and D2. Furthermore, the bracket 1 on the driving side
D3 between a and the pulley frame 23 may be divided. According to such a structure, the end of the shaft 22 mounted by overhanging the pulley 7 on the outside of the driving side bearing A is supported by the third bearing C, so that the bearing load of the driving side bearing A due to the belt load is also supported by the shaft. The diameter of 22 is also reduced. For this reason, the bearing A on the driving side becomes small in size, the d · n value of the bearing decreases, and grease lubrication can be used for those that must be oil lubricated. Since the pulley frame 23 to which the third bearing C is attached can be lathe-processed and has high accuracy, centering work is eliminated.

The handling method of this embodiment will be described. When removing the belt 7, the bottom 23a
3b and the bearing box 23c, the rounded end of the belt 7 may be pulled out around the bearing box 23c attached to the shaft 22, and then pulled out from the belt hole 24. When the belt 7 is newly wound, the reverse procedure is performed. However, it is faster to cut the belt when removing the damaged belt. When only replacing the belt 7,
It is not necessary to disassemble the bearing box 23c and the driving side bearing A from the shaft 22. Since the belt replacement period is generally shorter than the bearing inspection period, it is very convenient not to disassemble the bearing box 23c. Naturally, the maintenance of only the bearing housing 23c and the operating side bearing can be performed in the same manner as in the conventional case.

The case where the dividing unit D is other than the above will be described. When only D1 is used, the bearing box 23c is disassembled, the third bearing C is removed from the shaft 22, and the belt 7 is replaced. Division D
The joining direction of 1 is the reverse of the figure. In the case of only D2, the bearing box 23c integrated with the bottom portion 23a is disassembled, the third bearing C is removed from the shaft 22, and the belt 7 is replaced. In the case of only D3, the bearing box 23c integrated with the tubular portion 23b and the bottom portion 23a is disassembled, the third bearing C is removed from the shaft 22, and the belt 7 is replaced. The case of D1 + D2 has been described in the embodiment. D1 +
At the time of D3, the work of disassembling the bearing box 23c and the driving side bearing A from the shaft 22 is not necessary, but it is the same as the embodiment, but the cylindrical portion 23b integral with the bottom portion 23a is a little heavy, and while disassembling the belt. 7 must be routed around the bearing box 23c so as to be taken off. It is similar to the case of D2 + D3, but the joining direction of the divided portion D2 is reversed. D
The case of 1 + D2 + D3 has been described in the embodiment. The above is the combination of the division parts D, and D1 + D2 and D1 + D2 +
D3 is most purposeful, D1 + D3 and D2 + D3
Is next to this. Even if the dividing section D is at one location and only when the belt 7 is replaced, it is necessary to disassemble the bearing box 23c and remove the third bearing C from the shaft 22, which complicates the work. Suitable for. Is invention 3, is invention 4
Corresponds to Invention 5, and corresponds to Invention 6.

In the second embodiment shown in FIG. 3, instead of supporting the end portion of the shaft 22 by the third bearing C in the first embodiment, the third bearing of the bearing box 33c which is a part of the pulley frame 33 is used. The only difference is that C supports the end of the pulley 37. Division D
The state of combination is also the same as that of the first embodiment.

[0018]

According to the electric motor for driving the belt of the first aspect of the invention, since the end of the shaft mounted with the pulley overhung outside the bearing on the driving side is supported by the third bearing, the bearing on the driving side by the belt load is supported. Both bearing load and shaft diameter are reduced. For this reason, there is an effect that the bearing on the driving side becomes small in size, the d · n value of the bearing is lowered, and grease lubrication can be used for those that must be oil lubricated. Since the pulley frame for mounting the third bearing has high accuracy, it has an effect of eliminating the centering work and an effect of easily replacing the belt.

The effect of the electric motor for driving the belt according to the invention 2 is as follows.
Since the end of the pulley that overhangs outside the operating bearing is supported by the third bearing, the same effect as that of Invention 1 is obtained. According to the third aspect of the present invention, there is an effect that it is not necessary to disassemble the bearing box and the driving side bearing from the shaft when only the belt is replaced. According to the invention 4, the tubular portion can be individually removed,
This has the effect of making it easier to replace the belt. Invention 5
Alternatively, according to the sixth aspect of the invention, the work is a little heavy, but there is an effect that the work of disassembling the bearing box and the driving side bearing from the shaft is not required when only the belt is replaced.

[Brief description of drawings]

FIG. 1 is a one-sided sectional view of a first embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a one-sided sectional view of the second embodiment.

FIG. 4 is a side cross-sectional view of Conventional Example 1.

FIG. 5 is a half cross-sectional view of a driving side bearing device of Conventional Example 2.

FIG. 6 is a one-sided sectional view of Conventional Example 3.

[Explanation of symbols]

1a Bracket 1b Bracket 2 Shaft 3 Rotor 4 Frame 5 Stator 6 Pulley 7 Belt 22 Shaft 23 Pulley frame 23a Bottom 23b Cylindrical 23c Bearing box 24 Belt hole A Driving side bearing B Non-driving side bearing C 3rd bearing D Split section D1 division part D2 division part D3 division part

Claims (6)

[Claims] Claim: What is claimed is: 1. A rotor is fixed to a shaft supported by a bearing on the driving side and a bearing on the non-driving side mounted on a pair of brackets, and a tubular stator is fixed to a frame supporting the brackets. In a belt-driving electric motor in which a pulley is attached to the shaft protruding from the side bracket, and a belt is wound around the shaft, a bottomed cylindrical pulley frame including a bottom portion and a cylindrical portion is extended outside the operating side bracket. The pulley frame is divided into a bearing box provided with a third bearing and an outer periphery thereof by one or more desired dividing portions so as to be detachable, and a belt hole is opened in the pulley frame at a position corresponding to the belt. An electric motor for driving a belt, wherein an end of the shaft is supported by a third bearing. 2. A rotor is fixed to a shaft supported by a bearing on the driving side and a bearing on the non-driving side mounted on a pair of brackets, and a tubular stator is fixed to a frame supporting the both brackets. In a belt-driving electric motor in which a pulley is attached to the shaft protruding from the side bracket, and a belt is wound around the shaft, a bottomed cylindrical pulley frame including a bottom portion and a cylindrical portion is extended outside the operating side bracket. The pulley frame is divided into a bearing box provided with a third bearing and an outer periphery thereof by one or more desired dividing portions so as to be detachable, and a belt hole is opened in the pulley frame at a position corresponding to the belt. An electric motor for driving a belt, wherein an end of the pulley is supported by a third bearing. 3. The belt driving electric motor according to claim 1 or 2, wherein the dividing portion is between the bearing box and the bottom portion and between the bottom portion and the tubular portion. An electric motor for driving a belt. 4. The belt driving electric motor according to claim 3, wherein the dividing portion is located between the driving side bracket and the pulley frame. 5. The belt driving electric motor according to claim 1, wherein the split portion is between the bearing box and the bottom portion, and between the driving side bracket and the pulley frame. An electric motor for driving a belt characterized by. 6. The belt driving electric motor according to claim 1, wherein the dividing portion is between the bottom portion and the tubular portion and between the driving side bracket and the pulley frame. An electric motor for driving a belt characterized by.