JP7440364B2 - flat belt transmission system - Google Patents

Description

The present invention relates to flat belt transmission systems with serpentine control pulleys.

Conventionally, in transmission systems using flat belts, the flat belt may meander while running or run unilaterally to one side of the pulley. This is because flat belts are more sensitive than other flat belts to deviations of the pulley shaft from its normal position, deflection of the pulley shaft due to changes in shaft load, swinging of the pulley, and the like. In order to prevent such meandering and lopsided running, a flat belt meandering control device that prevents meandering of a flat belt is known (for example, see Patent Document 1).

Furthermore, a meandering control pulley having a one-way clutch is known as disclosed in Patent Document 2.

Japanese Patent Application Publication No. 2005-121205 Patent No. 6412293

In a flat belt transmission system that includes a fan such as a blower, the fan may rotate in the opposite direction (hereinafter referred to as "reverse rotation") due to wind or the like. In such a case, as described above, the flat belt tends to slip off the pulley, and when the rotation is reversed, the flat belt moves in a meandering direction, and the flat belt comes into contact with the flange of the pulley, damaging the side surface of the belt. Furthermore, in some cases, the flat belt may ride on the flange and fall off the pulley.

Furthermore, there is a need for a simple device that can prevent falling off due to reverse rotation without providing a one-way clutch as in Patent Document 2.

The present invention has been made in view of this problem, and its object is to provide a simple structure that reliably prevents the belt from falling off during reverse rotation.

In order to achieve the above object, the present invention provides a drop-off prevention guide roller that prevents the flat belt from falling off during reverse rotation.

Specifically, the flat belt transmission system of the first invention includes:
drive pulley;
a driven pulley;
a flat belt that is hung around the drive pulley and the driven pulley;
a meandering control pulley that comes into contact with the flat belt and controls the meandering of the flat belt by adjusting the inclination of the pulley shaft during normal rotation;
A drop-off prevention guide roller is provided that comes into contact with the side surface of the flat belt during reverse rotation and prevents the flat belt from falling off.

Normally, a meandering control pulley exhibits a meandering prevention function that prevents the flat belt from meandering by adjusting the inclination of the pulley shaft during normal rotation. However, when the fan rotates in the opposite direction due to strong winds, etc., it cannot perform its function due to its structure, and the meandering control pulley remains tilted in one direction, which causes the belt position to shift and eventually This results in shedding. However, according to the above configuration, the drop-off prevention guide roller comes into contact with the side surface of the flat belt that is about to fall off during the reverse rotation and prevents further movement in the falling direction, so the flat belt does not fall off even during the reverse rotation.

In the second invention, in the first invention,
The drop-off prevention guide roller is located between the drive pulley and the driven pulley.
disposed on the tension side, which pulls the flat belt when the drive pulley rotates in the normal direction; or on the slack side, where the flat belt loosens when the drive pulley rotates in the normal direction;
The meandering control pulley is disposed on the slack side of the drive pulley during normal rotation.

According to the above configuration, the drop-off prevention guide roller contacts the side surface of the flat belt on the tension side where the flat belt tends to fall off, so that the flat belt is reliably prevented from falling off. Further, even if it is provided on the slack side, the flat belt can still be prevented from falling off.

In the third invention, in the second invention,
When viewed in a direction perpendicular to the axis of the driven pulley, the outer circumferential surface of the drop-off prevention guide roller is 5 mm or less away from the side surface of the flat belt in its normal position during forward rotation, and In the normal position, the side surface of the flat belt and the drop-off prevention guide roller are configured not to come into contact with each other.

According to the above configuration, the flat belt can be prevented from contacting the drop-off prevention guide roller during normal rotation, but brought into contact during reverse rotation, and the belt position can be prevented from moving any further in the drop-off direction. Therefore, the side surface of the flat belt comes into contact with the drop-off prevention guide roller only when necessary, so that the durability of the flat belt is unlikely to deteriorate. Note that the normal position during forward rotation means a running position in which the flat belt does not meander (deviate).

In the fourth invention, in the second or third invention,
The drop-off prevention guide roller is disposed at a position of 100 mm or less from a contact point between the flat belt and the driven pulley when viewed from the axial direction of the driven pulley.

According to the above configuration, the rigidity of the flat belt is maintained at a position that is not unnecessarily distant from the driven pulley, and the position of the flat belt can be easily maintained.

In a fifth invention, in any one of the second to fourth inventions,
The drop-off prevention guide roller is also auxiliary provided on the driven pulley side between the drive pulley and the driven pulley.

According to the above configuration, the flat belt is more reliably prevented from falling off by the auxiliary provided fall-off prevention guide roller.

As described above, according to the present invention, since the drop-off prevention guide roller comes into contact with the side surface of the flat belt during reverse rotation, it is possible to reliably prevent the belt from falling off during reverse rotation with a simple structure.

1 is a perspective view showing an overview of a belt transmission system according to an embodiment of the present invention. FIG. 2 is an enlarged perspective view showing a drop-off prevention guide roller and its surroundings. FIG. 3 is a side view showing an outline of the belt transmission system during reverse rotation. FIG. 2 is a side view showing an overview of the belt transmission system during normal rotation.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a flat belt transmission system 1 according to an embodiment of the invention. In each figure, the forward rotation direction is shown by arrow F, and the reverse rotation direction is shown by arrow R.

Although not shown in detail, this flat belt transmission system 1 is used, for example, as a drive system for cooling towers, blowers, etc., and is connected to a drive pulley 2 driven by an actuator such as an electric motor, and a rotating shaft of a fan or the like. It includes a driven pulley 3 and a flat belt 6 that is hung around the driven pulley 3. This flat belt transmission system 1 is not limited to blowers, but can also be used for air conditioners, compressors, and the like. In particular, it targets systems that have no or almost no rotational fluctuations, unlike belt transmission systems that are attached to the output shaft of an engine. The flat belt 6 has a structure in which, for example, a core wire is provided at the center in the thickness direction, and this core wire is held between a top rubber and a bottom rubber. However, the type of the flat belt 6 is not particularly limited, nor is the material etc. particularly limited, and belts that tend to meander during running can also be used.

The flat belt transmission system 1 of this embodiment includes a meandering control device 4 that controls the meandering of the flat belt 6 by adjusting the inclination of the meandering control pulley 5 that comes into contact with the transmission surface of the flat belt 6. This meandering control device 4 includes a base portion 4a that is attached to a blower or the like, and a tension arm 4c that is swingably supported by an arm support shaft 4b at one end of the base portion 4a. A pulley shaft 7 that rotatably supports the control pulley 5 is provided. The meandering control pulley 5 is rotatably supported by a pulley shaft 7 via a bearing (not shown). Although a detailed explanation will be omitted (see Patent Documents 1 and 2 above), the meandering of the flat belt 6 is corrected by adjusting the inclination of the pulley shaft 7 by tilting the pin perpendicular to the pulley shaft 7. It looks like this. The tension arm 4c also functions as an auto-tensioner by being biased with a predetermined tensile force by a tension spring 4d provided at the other end of the base portion 4a. The meandering control device 4 autonomously controls the running position of the flat belt 6, and tension is stably maintained by the tension spring 4d, so that the flat belt 6 can have a long life and is maintenance-free.

As a feature of this embodiment, as shown in an enlarged view in FIG. 2, the flat belt transmission system 1 includes a drop-off prevention guide roller 10 that comes into contact with the side surface of the flat belt 6 and prevents the flat belt 6 from falling off. We are prepared. The drop-off prevention guide roller 10 includes, for example, a cylindrical guide roller body 11 and a guide roller support portion 12 that supports the roller rotation shaft 11a. For example, the guide roller support section 12 is fixed to the blower main body on which the driven pulley 3 and the like are supported.

The drop-off prevention guide roller 10 is arranged between the drive pulley 2 and the driven pulley 3 on the tension side that pulls the flat belt 6 when the drive pulley 2 rotates normally. On the other hand, the meandering control pulley 5 is arranged on the slack side of the drive pulley 2 when it rotates normally.

When viewed from a direction perpendicular to the axis of the driven pulley 3 (specifically, when viewed from the front in FIG. It is separated by x=5 mm or less from the side surface at the position. When the flat belt 6 is in its normal position, the side surface of the flat belt 6 and the drop-off prevention guide roller 10 are configured not to come into contact with each other. In other words, the minimum distance x is maintained without being too far apart than necessary.

The drop-off prevention guide roller 10 is arranged at a position L=100 mm or less from the point of contact between the flat belt 6 and the driven pulley 3 when viewed from the axial direction of the driven pulley 3. This value of 100 mm was set based on experimental values in which a predetermined belt rigidity was maintained.

-Operation of flat belt transmission system-
For example, an example in which the flat belt transmission system 1 is used in a blower will be described.

When the electric motor or the like is driven, the drive pulley 2 rotates in the normal rotation direction and the driven pulley 3 rotates, as shown in FIG. This power causes the fan to rotate. Since the meandering control device 4 also has an auto-tensioner function, the flat belt 6 is maintained at an appropriate tension by the tension of the tension spring 4d.

The meandering control pulley 5 has a meandering prevention mechanism in which when the flat belt 6 meanders during forward rotation, the pulley shaft 7 tilts around a pin perpendicular to the pulley axis in a direction that restores the meandering, thereby preventing meandering. Demonstrate function. Then, the flat belt 6 is subjected to a returning force (force to restore the offset) due to the meandering control pulley 5 being in an oblique state, and a returning force due to the tilting of the meandering control pulley 5. This prevents the belt 6 from shifting to one side.

The outer circumferential surface of the drop-off prevention guide roller 10 does not contact the flat belt 6 because it is separated by 5 mm or less from the side surface of the flat belt 6 in its normal position during normal rotation.

On the other hand, as shown in FIG. 3, when the fan on the driven side rotates in the opposite direction due to an external force such as a strong wind when the fan is stopped, the fan cannot perform its function. For this reason, the meandering control pulley 5 remains tilted in one direction, and the belt position starts to shift from that point, which may eventually lead to falling off.

However, in this embodiment, the drop-off prevention guide roller 10 comes into contact with the side surface of the flat belt 6 that is about to fall off when the flat belt 6 is reversed, and prevents it from moving further in the falling direction. Therefore, the flat belt 6 does not fall off even when the rotation is reversed.

In this embodiment, since the drop-off prevention guide roller 10 contacts the side surface of the flat belt 6 on the tension side where the flat belt 6 tends to fall off, the flat belt 6 is reliably prevented from falling off.

Furthermore, the flat belt 6 is not brought into contact with the drop-off prevention guide roller 10 during forward rotation, but is brought into contact only during reverse rotation, so that the belt position can be prevented from moving any further in the drop-off direction. That is, since the flat belt 6 is brought into contact with the drop-off prevention guide roller 10 only when necessary, the durability of the flat belt 6 is unlikely to deteriorate.

Furthermore, since the falling-off prevention guide roller 10 is arranged not far from the driven pulley 3, it comes into contact with the flat belt 6 at a position where its rigidity is maintained and prevents it from falling off, thereby maintaining the position of the flat belt 6. It's easy to do.

Therefore, according to the flat belt drive device 1 according to the present embodiment, the drop-off prevention guide roller 10 comes into contact with the side surface of the flat belt 6 during reverse rotation, thereby ensuring the meandering prevention function during normal rotation. A simple structure can reliably prevent the belt from falling off during reverse rotation. Thereby, the weaknesses peculiar to the meandering control device 4 can be eliminated.

-Modified example-
In the above embodiment, only one drop-off prevention guide roller 10 is provided on the tension side and the driven pulley 3 side, but for example, it may also be provided on the loose side and the drive pulley 2 side in the area surrounded by A in FIG. Good too.

Further, the drop-off prevention guide roller 10 may be provided on the slack side and the driven pulley 3 side. In this case as well, the drop-off prevention guide roller 10 is preferably disposed at a position L=100 mm or less from the point of contact between the flat belt 6 and the driven pulley 3 when viewed from the axial direction of the driven pulley 3. In this case, it may also be provided on the tension side and the driving pulley 2 side in the area surrounded by B in FIG.

(Other embodiments)
The present invention may have the following configuration for the above embodiment.

That is, the above embodiment is suitable for a flat belt transmission system 1 such as a blower in which there is no rotational fluctuation, but it can also be applied to a case where there is some rotational fluctuation.

Note that the above embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its applications, or uses.

1 Flat belt transmission system
2 Drive pulley
3 Driven pulley
4 Meandering control device
4a Base part
4b Arm support shaft
4c tension arm
4d tension spring
5 Meandering control pulley
6 flat belt
7 Pulley shaft
9 Bearing
10 Fall-off prevention guide roller
11 Guide roller body
11a Roller rotation axis
12 Guide roller support part

Claims (5)

drive pulley;
a driven pulley;
a flat belt that is hung around the drive pulley and the driven pulley;
a meandering control pulley that comes into contact with the flat belt and controls the meandering of the flat belt by adjusting the inclination of the pulley shaft during normal rotation;
A drop-off prevention guide roller that comes into contact with the side surface of the flat belt during reverse rotation to prevent the flat belt from falling off ;
The drop-off prevention guide roller is located between the drive pulley and the driven pulley.
The tension side or tension side that pulls the flat belt when the drive pulley rotates forward
The flat belt loosens when the drive pulley rotates in the forward direction, and is disposed on the slack side;
The meandering control pulley is arranged on the slack side of the drive pulley during forward rotation, so that
The flat belt is configured not to come into contact with the drop-off prevention guide roller during forward rotation, and the drop-off prevention guide roller is brought into contact with the side surface of the flat belt that is about to fall off only during reverse rotation.
A flat belt transmission system characterized by: The flat belt transmission system of claim 1 ,
When viewed in a direction perpendicular to the axis of the driven pulley, the outer circumferential surface of the drop-off prevention guide roller is 5 mm or less away from the side surface of the flat belt in its normal position during forward rotation, and A flat belt transmission system characterized in that, in a normal position, a side surface of the flat belt and the drop-off prevention guide roller do not come into contact with each other. The flat belt transmission system according to claim 1 or 2 ,
A flat belt transmission system, wherein the drop-off prevention guide roller is disposed at a position of 100 mm or less from a contact point between the flat belt and the driven pulley when viewed from the axial direction of the driven pulley. The flat belt transmission system according to any one of claims 1 to 3 ,
The drop-off prevention guide roller is provided on the tension side and the driven pulley side between the drive pulley and the driven pulley, and is additionally provided on the slack side and the drive pulley side. Belt transmission system. The flat belt transmission system according to any one of claims 1 to 3,
The drop-off prevention guide roller is provided between the drive pulley and the driven pulley on the slack side and the driven pulley side, and is additionally provided on the tension side and the drive pulley side.
A flat belt transmission system characterized by:

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