JP2000120814A - Power transmitting mechanism attached equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and mass-producible power transmitting mechanism attached equipment not causing any tooth skipping phenomenon of a toothed belt even when impact of transmitted power or locked condition is powerful. SOLUTION: This power transmitting mechanism attached equipment is provided with a motor 11 for generating power, a loading means, and a power transmitting means for transmitting the power generated by the motor 11 to the loading means, while the power transmitting means is composed of a toothed belt 12 and a flat belt 17 and the toothed belt 12 is prevented from tooth skipping by the flat belt 17 slipping when a locked condition takes place in the transmission system and absorbing the lock impact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device having a power transmission mechanism using a belt.

[0002]

2. Description of the Related Art As shown in FIG. 6, a conventional device having a power transmission mechanism having a toothed belt generally has a power means 1 comprising an electric motor, a small pulley 3 which is driven to rotate by the power means 1, and a load. A large pulley 4 connected to the side and receiving power, and a toothed belt 2 that is stretched around the small pulley 3 and the large lee 4 and transmits power.

When the margin of the toothed belt 2 hanging on the small pulley 3 is small, an auxiliary pulley 5 is additionally provided.

There is no problem if the transmitted power or the impact torque in the locked state is relatively small, but if it is large, a large tension is applied to each pulley from the initial state to prevent the toothed belt 2 from jumping. The pulley 3 has a large allowance, the width of the toothed belt 2 is large, the toothed belt 2 having a large tooth groove is used, and a metal pin 6 for preventing tooth skipping is provided with the toothed belt of the small pulley 3. It was provided behind two.

[0005]

In the conventional toothed belt speed reduction mechanism, the initial tension is reduced in order to prevent the toothed belt 2 from jumping when the transmission power or the shock in the locked state is large. In the case of a large setting, the pulley support structure that can withstand the total tension including the initial tension and the tension during operation is required in combination with the high rigidity of the toothed belt 2.

When the initial tension is suppressed, the width of the toothed belt 2 is increased, the toothed belt 2 having a large tooth gap is used, and the metal pins 6 for preventing tooth skipping are attached to the small pulley 3. However, the transmission power and the impact in the locked state are limited to relatively small ones, and the cost is high.

In addition, since the toothed belt 2 has high rigidity, there is a dilemma that an increase in the belt width or a belt having a large tooth gap results in an increase in the initial tension.

The present invention is intended to solve the above-mentioned conventional problems. Particularly, even if the transmission power or the shock in the locked state is large, the toothed belt 2 does not cause the tooth jumping phenomenon. It is another object of the present invention to provide a device with a power transmission mechanism that has a low initial tension, reduces an excessive load on the pulley, can simplify the pulley support structure, is inexpensive, and has good mass productivity.

[0009]

In order to achieve the above object, the present invention provides a power generating means for generating power, a load means,
Power transmission means for transmitting the power from the power means to the load means, and the power transmission means is constituted by a toothed belt and a friction system belt. The belt slips and absorbs the lock impact, and the tooth jumping phenomenon of the toothed belt does not occur, so the setting of the toothed belt has a large degree of freedom, for example, the initial tension is small, and the excessive load on the pulley is reduced, It is possible to provide an inexpensive and mass-produced device with a power transmission mechanism in which the pulley support configuration is simplified and the belt width is set to a minimum necessary for the transmission power.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION
Power means for generating power, load means, and power transmission means for transmitting the power from the power means to the load means, and the power transmission means is constituted by a toothed belt and a friction system belt, so that the transmission system When the lock state occurs in either case, the friction belt slips and absorbs the shock of the lock, the tooth jumping phenomenon of the toothed belt does not occur, and the setting of the toothed belt has a large degree of freedom, for example, in the initial state, It is possible to provide an inexpensive and mass-produced device with a power transmission mechanism that has low tension and reduces the excessive load on the pulley, simplifies the pulley support configuration, and sets the belt width to the minimum necessary for transmission power. .

According to a second aspect of the present invention, a speed reduction mechanism is connected to each of the toothed belt and the friction system belt.
It is possible to provide a device with a power transmission mechanism that is inexpensive and has good mass productivity even with a speed reduction mechanism, because the friction belt can slip and absorb the shock of the lock.

According to a third aspect of the present invention, a speed reduction mechanism connected to a toothed belt includes a toothed belt transmitting power, a small pulley rotated by power means, and a large pulley receiving power. A small pulley is composed of an auxiliary pulley that increases the allowance for the toothed belt, and the auxiliary pulley is composed of each pulley from the circumference of the toothed belt so that the initial tension of the toothed belt is small when the auxiliary pulley is at rest. Since the belt is located at a position where the circumference of the belt is large, only the tension on the tension side of the belt during operation is applied to each pulley, and during operation the auxiliary pulley allows a large amount of engagement for the small pulley, so that tooth jump does not occur, Since the initial tension is small, an excessive load on the pulley can be reduced, and the pulley receives only the necessary minimum tension on the tension side during operation. Therefore, the support structure of the pulley can be simplified, and a device with a power transmission mechanism that is inexpensive and has high mass productivity can be provided.

In the invention according to claim 4 of the present invention, the auxiliary pulley is held by a spring so as to be movable in the vertical direction with respect to the toothed belt so that a constant tension is applied to the toothed belt. When a lock state occurs in any of the belt reduction systems, the auxiliary pulley absorbs the shock of the lock.
Therefore, tooth jump of the toothed belt can be prevented.

In the invention according to claim 5 of the present invention, two auxiliary pulleys are provided so as to face each other with the small pulley interposed therebetween. Therefore, even if the rotation direction of the power means changes, one auxiliary pulley is always connected to the non-tension side. The toothed belt has a large allowance on the deflection side to prevent tooth skipping. Therefore, even if the rotation direction of the power means changes, an effect of preventing tooth jump can be obtained.

In the invention according to claim 6 of the present invention, a belt guide is provided so as to cover the belt from the back with a space equal to or less than the tooth height of the toothed belt from the back of the toothed belt on the small pulley. Therefore, even if the slack occurs on the non-tension side of the toothed belt, the teeth of the belt do not fall out of the tooth groove of the pulley, and the teeth do not jump. Therefore, the effect of preventing tooth jump can be obtained irrespective of the initial tension, and the same effect of preventing tooth jump can be obtained even if the rotation direction of the power unit changes because the belt is covered.

According to a seventh aspect of the present invention, in the belt guide, a rib perpendicular to the operation direction of the belt is provided so as to contact the rear surface of the belt on the small pulley, and the vertical rib is provided on the non-tension side. The belt is held down by the ribs even on the non-tension side of the toothed belt, so that no slack occurs on the small pulley, and the teeth of the belt are in the groove of the pulley. It does not come off and does not jump. Therefore, the effect of preventing tooth jump can be obtained irrespective of the initial tension, and the same effect of preventing tooth jump can be obtained even if the rotation direction of the power unit changes because the belt is covered. In addition, since it is irrelevant to the tooth height of the belt, it can be used for a belt having a low tooth height.

[0017]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, a small flat belt pulley 16 is attached to an electric motor 11 serving as a power source, and power is supplied to a large flat belt pulley 18 on the reduction side via a flat belt 17. Tells. Flat belt large pulley 18
Is fixed to a drive shaft 19, and the toothed belt small pulley 13 is fixed to the drive shaft 19 adjacent to the flat belt large pulley 18.

Both ends of the drive shaft 19 are held by metal bearings 20. The power of the small toothed belt pulley 13 is transmitted via the toothed belt 12 to the large toothed belt pulley 14 on the reduction side. The toothed belt large pulley 14 is provided with a rotating shaft 21 connected to a load means (not shown).
Is cantilevered.

The rotating shaft 21 is held by a housing 22. The housing 22 is screwed to a stopper plate 23. In the vicinity of the toothed belt small pulley 13,
Two auxiliary pulleys 15 are provided so as to oppose the toothed belt 12 from the back to the small toothed belt pulley 13 with a large allowance, and the position is set in a state where the toothed belt 12 is attached. The position is set at a position where the length of the toothed belt 12 has a margin and the initial tension is not applied. The auxiliary pulley 15 is cantilevered by an auxiliary pulley shaft 24, and is fixed to the housing 22 via a stopper plate 23. In addition, the electric motor 11 is configured to be able to rotate left and right.

The operation of the above configuration will be described. The power generated by the electric motor 11 is controlled by the flat belt small pulley 1.
6 is transmitted to the flat belt large pulley 18 via the flat belt 17 at a reduced speed. The power transmitted to the large flat belt pulley 18 is the drive shaft 1 held by the metal bearing 20.
9 is transmitted to the large toothed belt pulley 14 supported by the rotating shaft 21 via the toothed belt 12 from the small toothed belt pulley 13 at a reduced speed.

At this time, when a lock with a large impact occurs at the end of the drive system, the flat belt 17 of the friction system belt slips to absorb the shock of the lock, and the toothed belt 12 receives the impact and receives the impact. This prevents so-called tooth jump (jumping) in which the tooth grooves of the toothed belt pulley 13 and the toothed belt 12 are displaced.

Therefore, the setting of the toothed belt 12 has a large degree of freedom, for example, the setting in which the initial tension is not applied as in this embodiment, and the excessive load on each pulley can be reduced. It is possible to provide an inexpensive device with a power transmission mechanism that can simplify the configuration and that has the width of the toothed belt 12 set to the minimum necessary for the transmission power and that has good mass productivity.

In addition, since the load on the toothed belt 12 is reduced, a highly reliable device with a power transmission mechanism that can maintain the quality of the toothed belt 12 for a long period of time can be provided.

Further, according to the speed reduction mechanism for the toothed belt 12 of the above embodiment, the toothed belt 12 is attached without initial tension regardless of the tension setting of the flat belt 17, but the power is transmitted. , Toothed belt 12
The teeth on the tight side of the toothed belt are large (14) and small (13)
The power is transmitted to the tooth space of the pulley. Therefore, since only a necessary minimum tension on the pulley of the toothed belt 12 during operation is applied to each pulley of the toothed belt 12, the support structure of each pulley of the toothed belt 12 can be simplified such as one-sided support by the metal bearing 20 as in the embodiment. It is possible to provide a toothed belt reduction mechanism that can be configured and is inexpensive and excellent in mass productivity. This is particularly suitable when the toothed belt 12 is wide and the initial tension is large, or when the difference in the length of the toothed belt 12 is large and the difference in tension is large between the shortest belt and the longest belt.

At this time, by setting the initial tension not to be applied, the deflection of the toothed belt 12 on the non-tension side is generated, the hooking margin of the toothed belt 12 is reduced, and the tooth jump is more likely to occur. In order to prevent this, the auxiliary pulley 14 increases the allowance of the toothed belt 12 of the toothed belt small pulley 13 to increase the number of teeth on the auxiliary pulley 14, so that the force applied to each tooth is reduced. No tooth jumps. Therefore, tooth skipping can be prevented with a highly productive and inexpensive configuration using a fixed auxiliary pulley without a tension adjusting function.

The auxiliary pulley 14 is provided with the toothed belt 1.
2, the auxiliary pulley 14 on one side is always on the non-tension side even if the rotation direction of the electric motor 11 changes, so that a large allowance on the bending side of the toothed belt 12 is taken, and tooth skipping occurs. I'm preventing. Therefore, even if the rotation direction of the electric motor 11 changes, an effect of preventing tooth jump can be obtained.

(Embodiment 2) Next, a second embodiment of the present invention will be described.
This will be described with reference to FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

A belt guide 25 is provided so as to cover the toothed belt 12 from the back with an interval A less than the tooth height of the toothed belt 12 from the back of the toothed belt 12 on the small pulley 13. Was.

The operation of the above-described configuration will be described. Even if slack occurs on the non-tension side of the toothed belt 12, a belt guide exists on the back of the toothed belt 12 at an interval A equal to or less than the tooth height of the toothed belt 12. Therefore, the teeth of the toothed belt 12 do not fall out of the tooth groove of the toothed belt small pulley 13, and no tooth jump occurs. Belt 1 with teeth from the back
2 is not limited to the rotation direction of the electric motor 11, and has an effect of preventing tooth jump.

Therefore, it is possible to provide a device with a power transmission mechanism that does not cause tooth jump by minimizing additional parts.

Embodiment 3 Next, a third embodiment of the present invention will be described.
This will be described with reference to FIG. Note that the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

A rib 26 projecting toward the center of the drive shaft 19 of the toothed belt 12 is provided on the belt guide 25 by the toothed belt 1
2 was provided so as to be in contact with the back surface of the non-stretched end.

The operation of the above-described structure will be described.
6, no slack occurs on the small toothed belt pulley 13, and the teeth of the toothed belt 12 do not fall out of the tooth grooves of the small toothed belt pulley 13, and no tooth jump occurs. Therefore, by contacting the toothed belt 12 from the back surface, the belt is directly pressed, and the effect of preventing tooth skipping can be obtained regardless of the tooth height of the toothed belt 12.

Accordingly, a belt with a small tooth height can be employed regardless of the tooth height of the toothed belt 12, and an additional component can be minimized to provide a device with a power transmission mechanism that does not cause tooth jump.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described.
This will be described with reference to FIG. Note that the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

One auxiliary pulley shaft 24 of the auxiliary pulley 15 is held by a holding fitting 27 provided with a groove in a direction perpendicular to the toothed belt 12, and an end of a spring 28 is further inserted between the two auxiliary pulley shafts. The toothed belt 12 was hung so that a constant tension was applied.

The operation of the above configuration will be described. During normal operation, a certain tension is applied to the toothed belt by the auxiliary pulley 15 held movably in the vertical direction with respect to the toothed belt 12. , Toothed belt 12
When the lock state occurs in any of the speed reduction systems, one of the auxiliary pulleys 15 is held by the spring 28,
The lock prevents the tension of the toothed belt 12 from suddenly increasing suddenly, and protects the toothed belt 12 system from the impact of the lock. Therefore, tooth jump of the toothed belt 12 can be prevented.

Although the present embodiment has described the toothed belt reduction mechanism of the electric motor 11, the same can be said of the toothed belt acceleration mechanism of the electric motor 11.

[0040]

As is apparent from the above embodiment, according to the first aspect of the present invention, the power means for generating power, the load means, and the power generated by the power means are transferred to the load means. Since the power transmission means is constituted by a toothed belt and a friction system belt, even if a lock state occurs in any of the transmission systems, the friction system belt slips and the impact of the lock is generated. The so-called tooth jumping phenomenon in which the tooth of the pulley is displaced from the tooth of the belt of the toothed belt which is absorbed by the toothed belt does not occur, and the degree of freedom in setting the toothed belt is increased. Therefore, for example, the initial tension is small, the excessive load on the pulley is reduced, the support of the pulley can be easily configured, and the belt width is set to the minimum necessary for the transmission power. Equipment can be provided.

According to the second aspect of the present invention, the speed reduction mechanism is connected to each of the toothed belt and the friction system belt, so that even if a lock state occurs in any of the speed reduction systems, the friction is reduced. It is possible to provide a device with a power transmission mechanism that is inexpensive and has good mass productivity even with a speed reduction mechanism, while the system belt slips to absorb the shock of the lock.

According to the third aspect of the present invention, the speed reduction mechanism using the toothed belt includes a toothed belt for transmitting power, a small pulley rotated by power means,
It consists of a large pulley that receives power, and an auxiliary pulley to increase the allowance of the toothed belt on the small pulley, and the auxiliary pulley is toothed so that the initial tension of the toothed belt is small when stationary. The pulley is located at a position where the circumference of the belt composed of each pulley is larger than the circumference of the belt.Therefore, only the necessary tension on the belt tension side during operation is applied to each pulley, and the initial tension is small. Excessive load can be reduced. Therefore, each pulley can be configured to have a simple configuration such as one-side support by a metal bearing or an auxiliary pulley without tension adjustment, and a device with a power transmission mechanism that is inexpensive and excellent in mass productivity can be provided.
It is particularly suitable when the toothed belt is wide and the initial tension is large, or when the tolerance of the belt length is large and the difference in tension is large between the shortest belt and the longest belt.

At this time, by setting the initial tension to be small, the non-tension side deflection of the toothed belt is generated, and the belt allowance is reduced, so that the tooth jump is prevented from easily occurring. As the pulley increases the allowance of the toothed belt of the small pulley and obtains the number of teeth on it,
The force applied to each tooth is reduced, so that tooth skipping does not occur.

According to the fourth aspect of the present invention, the auxiliary pulley is held by a spring so as to be movable in the vertical direction with respect to the toothed belt so that a constant tension is applied to the toothed belt. Since the auxiliary pulley is held by a spring when a lock state occurs in any of the toothed belt speed reduction systems, the shock of the lock is absorbed and only a constant tension is applied to the toothed belt. . Therefore, tooth jump of the toothed belt can be prevented.

According to the invention of claim 5 of the present invention, the auxiliary pulley is arranged so as to face the small pulley.
Since the auxiliary pulleys are provided separately, the auxiliary pulley on one side is always on the non-tension side even if the rotation direction of the power means changes, so that the allowance on the bending side of the toothed belt is increased to prevent tooth jump. Therefore, even if the rotation direction of the power means changes, an effect of preventing tooth jump can be obtained.

According to the invention of claim 6 of the present invention, the belt is covered from the back with an interval equal to or less than the tooth height of the toothed belt from the back of the toothed belt on the small pulley. Because the belt guide is provided, even if slack occurs on the non-tension side of the toothed belt, the teeth of the toothed belt do not fall out of the tooth groove of the small pulley, no tooth jump occurs, and the belt covers the belt from the back. Therefore, there is an effect of preventing tooth skipping regardless of the rotation direction of the power means. Therefore, it is possible to provide a device with a power transmission mechanism that does not cause tooth skipping by minimizing additional parts.

According to the seventh aspect of the present invention, the belt guide is provided with a rib perpendicular to the operation direction of the belt so as to contact the back surface of the belt on the small pulley. Is provided at least at one position near the end of the hook of the belt on the non-tension side, so the toothed belt is pressed by the rib even on the non-tension side of the toothed belt, and no slack occurs on the small pulley, The teeth of the belt do not fall out of the tooth space of the small pulley, and no tooth jump occurs. Therefore, by contacting the belt from the back surface, the belt can be directly pressed, and the effect of preventing tooth jump can be obtained regardless of the tooth height of the toothed belt. Therefore, regardless of the tooth height of the toothed belt, a belt with a small tooth height can be adopted, and additional components can be minimized to provide a device with a power transmission mechanism that does not cause tooth skipping.

[Brief description of the drawings]

FIG. 1 is a front view of a toothed belt reduction mechanism of a device with a power transmission mechanism according to a first embodiment of the present invention.

FIG. 2 is a top view of a main part of the toothed belt reduction mechanism.

FIG. 3 is a top view of a main part of a toothed belt reduction mechanism of a device with a power transmission mechanism according to a second embodiment of the present invention.

FIG. 4 is a top view of a main part of a toothed belt reduction mechanism of a device with a power transmission mechanism according to a third embodiment of the present invention.

FIG. 5 is a top view of a main part of a toothed belt reduction mechanism of a device with a power transmission mechanism according to a fourth embodiment of the present invention.

FIG. 6 is a top view of a main part of a toothed belt reduction mechanism of a device with a power transmission mechanism showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1,11 Power means (electric motor) 2,12 Toothed belt 3,13 Toothed belt small pulley 4,14 Toothed belt large pulley 5,15 Auxiliary pulley 17 Friction belt (flat belt) 25 Belt guide 26 Rib 28 Spring

Claims (7)

[Claims] 1. A power generating means for generating power, a load means, and a power transmitting means for transmitting the power from the power means to the load means, wherein the power transmitting means comprises a toothed belt and a friction belt. Equipment with power transmission mechanism. 2. The device with a power transmission mechanism according to claim 1, wherein a reduction mechanism is connected to each of the toothed belt and the friction belt. 3. A speed reducing mechanism connected to a toothed belt,
It consists of a toothed belt that transmits power, a small pulley that rotates by power means, a large pulley that receives power, and an auxiliary pulley that increases the allowance of the toothed belt of the small pulley, and the auxiliary pulley is in a stationary state. 3. A geared belt speed reduction mechanism according to claim 2, wherein said geared belt speed reduction mechanism is arranged at a position where the circumference of the belt formed by each pulley is larger than the circumference of the toothed belt so that the initial tension of the toothed belt is reduced. Equipment with power transmission mechanism. 4. The toothed belt reduction mechanism according to claim 3, wherein the auxiliary pulley is held by a spring so as to be movable in the vertical direction with respect to the toothed belt so that a constant tension is applied to the toothed belt. Equipment with power transmission mechanism. 5. The device with a power transmission mechanism according to claim 3, wherein a toothed belt speed reduction mechanism provided with two auxiliary pulleys facing each other across the small pulley is used. 6. A toothed belt speed reduction mechanism provided with a belt guide so as to cover the belt from the back with a space equal to or less than the tooth height of the toothed belt from the back of the toothed belt on the small pulley. An apparatus with a power transmission mechanism according to any one of claims 3 to 5. 7. A belt perpendicular to the belt operating direction is provided on the belt guide so as to be in contact with the back surface of the belt on the small pulley, and the vertical rib is provided near the end of the non-tension side belt hook. The device with a power transmission mechanism according to claim 6, wherein a toothed belt reduction mechanism provided at least at one or more locations is used.