JP2022184765A - Toothed pulley, synchronization belt system and attachment method of toothed pulley - Google Patents

Abstract

To provide a toothed pulley or the like which can attach a belt between pulleys so as to be capable of setting the attachment tension of the belt to a comparatively-high level even if the belt which is comparatively high in belt elasticity is attached to a pulley layout having no tension impartment mechanism which is in a common use in a prior art (the movement of an inter-axis distance, a tension pulley, a tensioner or the like).SOLUTION: A toothed pulley 1 in which a groove part 14 engaged with a tooth part 21 of a toothed belt 2 is formed at an external periphery comprises: a boss part 111 which can be connected to a rotating shaft; a first split pulley 12 and a second split pulley 13 which are attached to an external peripheral side of the boss part 111, and split into two pieces in a circumferential direction of the boss part 111; and a base member 11 for fixing a positional relationship of the first split pulley 12 and the second split pulley 13 in a rotating shaft direction. The first split pulley 12 is attachable to the external peripheral side of the boss part 111 in a state that the second split pulley 13 is not attached to the external peripheral side of the boss part 111.SELECTED DRAWING: Figure 3

Description

The present invention relates to a toothed pulley, a synchronous transmission belt system using the same, and a method of mounting a toothed belt in the synchronous transmission belt system.

Meshing transmission belts such as toothed belts are widely used in belt systems for automobile engines and general industrial machinery. A meshing transmission belt transmits power through mechanical meshing between the grooves of the pulleys and the teeth of the belt. In such meshing transmission belts, it is necessary to maintain the meshing during running in order to ensure a synchronous transmission system.

However, if the belt stretches and loosens during running, the meshing becomes defective (problems such as tooth skipping occur). is required.

Conventionally, the following method is applied as a method of mounting a toothed belt with a relatively high belt elastic modulus (hereinafter sometimes abbreviated simply as "belt", and the width of the belt is assumed to be 20 mm) between pulleys. It is

(A) Tension is applied to the belt by pushing or pulling the belt with a tensioner (tension pulley) in a relaxed state in which the belt is suspended over two or more pulleys.
(B) Tensioning the belt by moving at least one pulley shaft to widen the distance between the pulley shafts in a relaxed state in which the belt is suspended over two or more pulleys.
(C) A method of mounting a belt on a pulley layout that does not have the above-described tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.), wherein the pulley layout circumference (see definition below) is the belt reference circumference The belt is suspended on a pulley layout (two or more pulleys) that is the same or slightly shorter than (see definition below) and is loaded between the pulleys with little tension applied to the belt during loading.

In particular, by adopting the above method (C), the conventional and commonly used tensioning mechanisms (movement of the distance between shafts, tension pulleys, tensioners, etc.) such as the above (A) and (B) are no longer required, and the synchronous transmission belt Contributes to system weight reduction and cost reduction.

JP-A-56-31557 JP-A-08-24249

In the case of a belt with a relatively high level of elastic modulus (for example, about 200 to 400 KN at a belt width of 20 mm), the above method (C), that is, the conventional tension applying mechanism (movement of the distance between axes, tension pulley , tensioner, etc.), the belt can be installed by human hands (without jigs and tools), but almost no tension (initial tension) is applied to the belt when installed (for example, when installed at about 100 N Even if it is a mounting method in which only tension is applied, it still has a certain level of transmission capacity because the belt system is meshing transmission.

However, in order to improve the transmission performance (anti-tooth skipping performance, etc.) of the belt for applications with higher loads, it is essential to raise the tension (initial tension) applied to the belt when it is attached.

In the above method (C), the tension (initial tension) when the belt has a relatively high level of elastic modulus (for example, about 200 to 400 KN) is set to a relatively high level (for example, about 200 to 400 N). , it is necessary to provide a pulley layout such that the pulley layout circumference is slightly (for example, about 0.05% to 0.1%) longer than the belt reference circumference.

However, since belts with a relatively high level of elastic modulus (for example, about 200 to 400 KN) are used as a basis, it is difficult to mount the belt on the pulley layout, and this has not been possible.

In this regard, as a means for solving the above problems, we have investigated documents related to conventional toothed pulleys and found Patent Document 1 and Patent Document 2, but these documents describe the above problems, means for solving them, and No suggestions were found.

Therefore, the object of the present invention is to provide a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.) even when a belt with a relatively high belt elastic modulus is attached. Another object of the present invention is to provide a toothed pulley or the like which enables the tension of the belt to be set to a relatively high level and allows the belt to be mounted between the pulleys.

The present invention relates to a toothed pulley having grooves formed on its outer circumference that mesh with teeth of a toothed belt,
a boss connectable to the rotating shaft;
a plurality of divided pulleys attached to the outer peripheral side of the boss portion and having a shape divided into a plurality of portions in the circumferential direction of the boss portion;
fixing means for fixing the positional relationship of the plurality of split pulleys in the direction of the rotation axis;
with
Of the plurality of split pulleys, some of the split pulleys can be attached to or integrated with the outer periphery of the boss while the remaining split pulleys are not attached to the outer periphery of the boss. It is characterized by having

According to the above configuration, the boss portion is connected to the rotating shaft and attached to the outer peripheral side of the boss portion, or integrated with the outer peripheral side of the boss portion. By providing the pulley layout in such a manner that the arc portion connecting the outer edges of the grooves formed on the outer circumference of some of the split pulleys stays in the inner region of the circumference of the pulley layout including the toothed pulley, The circumference (L1) of the pulley layout including the toothed pulleys before the toothed belt is attached can be shortened with respect to the belt reference circumference (L0) of the toothed belt. Therefore, a toothed belt having a relatively high belt elastic modulus can be easily suspended on the pulley layout including the toothed pulley including a part of the split pulleys.
Then, the toothed pulley including some of the split pulleys can be rotated to apply tension to the toothed belt at the time of attachment. Therefore, the toothed pulley functions as a tension applying mechanism when the toothed belt is mounted on the pulley layout.
Then, by attaching the remaining split pulleys to the outer peripheral side of the boss portion via fixing means, a toothed pulley having exactly the same external shape (annular shape) and function as a normal toothed pulley can be used for synchronous transmission. Can be applied to belt systems.
Therefore, according to the above configuration, a toothed belt having a relatively high belt elastic modulus is attached to a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.). Even so, it is possible to provide a relatively high level of tension when the toothed belt is worn.

Further, according to the present invention, in the toothed pulley, the number of the plurality of split pulleys may be two.

According to the above configuration, compared to the case where the number of split pulleys is 3 or more, it takes less time and effort to manufacture the toothed pulley and to install the toothed belt between the pulleys (assembling the remaining split pulleys). It can save you time.

Further, according to the present invention, in the toothed pulley, the groove may have a shape extending in the rotation axis direction.

According to the above configuration, the groove extends parallel to the pulley width direction. Compared to a toothed pulley other than a straight toothed pulley (for example, a helical toothed pulley in which the toothed pulley has grooves arranged obliquely with respect to the pulley width direction), It becomes easy to attach the toothed belt (more specifically, it becomes easy to apply the remaining split pulleys to some of the split pulleys along the pulley width direction (rotational axis direction)). In addition, since the allowable range of the toothed belt winding angle can be expanded accordingly, the flexibility of the pulley layout can be further enhanced.

Further, according to the present invention, in the above-described toothed pulley, the fixing means has a configuration in which the boss portion and a flange portion extending radially outward from one side of the boss portion are integrally formed,
Furthermore, it may be characterized by having a fastening member that fastens the plurality of split pulleys and the flange portion.

According to the above configuration, it is possible to more reliably fix the positional relationship of the plurality of split pulleys in the rotation axis direction on the outer peripheral side (radial direction outside) of the boss portion. In addition, the degree of freedom in designing (configuration) of the toothed pulley can be increased.

Further, according to the present invention, in the toothed pulley, the flange portion may extend from one side of the boss portion to at least an outer edge of the groove portion.

According to the above configuration, it is possible to prevent the toothed belt from falling off from the toothed pulley, and to improve the running stability of the toothed belt along the pulley layout (path of the toothed belt).

In the toothed pulley according to the present invention, the split pulley and the fixing means are concentrically fitted with a recess formed on one side and a protrusion formed on the other side. It may be characterized by a structure that

According to the above configuration, the split pulley and the fixing means can have a fitting structure. As a result, the toothed pulley (final shape) after assembling the plurality of split pulleys and the fixing means can be made to be a toothed pulley having exactly the same external shape (annular shape) and function as a normal toothed pulley. High dimensional accuracy can be achieved.

In the toothed pulley according to the present invention, the split pulley has the convex portion on one side, the fixing means has the concave portion on one side, and the convex portion and the concave portion are concentrically fitted. It is good also as a feature that it is constituted so that it is possible.

Contrary to this configuration, if one side of the split pulley has a concave portion and one side of the fixing means has a convex portion, the toothed pulley with only a part of the split pulley attached to the outer peripheral side of the boss portion can be used. When attaching the toothed belt to the pulley layout (temporarily attaching), especially in the process of applying tension to the toothed belt, the toothed belt is carelessly attached to the protrusion projecting to one side of the fixing means. There is a risk that the toothed belt will be damaged by riding on it.
However, according to this configuration, since there is no protrusion projecting from one side of the fixing means, the toothed belt can be prevented from being damaged when the toothed belt is attached to the pulley layout.

Further, according to the present invention, in the above toothed pulley, the plurality of split pulleys may be split in the circumferential direction at the bottom surface of the groove.

Contrary to this configuration, if a plurality of split pulleys are configured to be divided in the circumferential direction at a portion other than the bottom of the groove (for example, a portion facing the tooth root or tooth bottom of the belt), the outer circumference of the boss portion When attaching a toothed belt to a pulley layout using a toothed pulley with only some split pulleys attached (temporary attachment), especially in the process of applying tension to the toothed belt, When the relatively thin belt portion (tooth base and tooth bottom) contacts the outer peripheral side end (corner) of the dividing surface, the toothed belt is bent, and there is a risk of cracking or breaking. There is
However, according to this configuration, the dividing surface is formed starting from the bottom surface of the groove portion, and the pulley is divided in the circumferential direction. Since it is the tip portion of the toothed belt that comes into contact with the portion (corner), it is possible to prevent the above defects (cracks, etc.) from occurring.

Further, the present invention provides a toothed belt having a plurality of teeth arranged at predetermined intervals along the longitudinal direction of the belt, and two or more toothed pulleys spaced apart from each other to which the toothed belt is attached. A synchronous transmission belt system comprising a pulley layout consisting of
At least one of the two or more toothed pulleys is the toothed pulley according to any one of claims 1 to 8,
The part of the split pulleys can be attached to the outer periphery of the boss or integrated with the outer periphery of the boss while the remaining split pulleys are not attached to the outer periphery of the boss. Functioning as a belt mounting pulley used when mounting to the pulley layout,
Before the toothed belt is attached to the pulley layout, when viewed in the direction of the rotation axis, an arc portion that connects the outer edges of the grooves formed on the outer circumference of the partial split pulley is formed by connecting the toothed pulley. It is characterized in that it is configured so as to be able to be arranged in a mode that it stays in the inner region of the circumference of the pulley layout that includes the pulley layout.

According to the above configuration, a toothed belt having a relatively high belt elastic modulus is attached to the pulley layout of a synchronous transmission belt system that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.). Even in this case, it is possible to provide a relatively high level of tension when the toothed belt is worn.

Further, according to the present invention, in the synchronous transmission belt system, only one of the two or more toothed pulleys may be the toothed pulley described above.

According to the above configuration, it is possible to minimize the manufacturing cost of the synchronous transmission belt system (especially the pulley layout) and the labor of mounting the toothed belt on the pulley layout.

Further, in the synchronous transmission belt system according to the present invention, the central angle of the arc portion when viewed in the direction of the rotation axis is equal to or greater than the winding angle of the toothed belt with respect to the toothed pulley, and the arc portion The center angle of the pulley layout is the circumferential length (L1 ) is within a range that is less than the belt reference circumferential length (L0) of the toothed belt.

According to the above configuration, it is possible to reliably secure the wearability of the toothed belt (in particular, the workability of attaching the remaining split pulleys to the outer peripheral side of the boss portion).

The present invention also provides a method for mounting the toothed belt on the pulley layout in the synchronous transmission belt system,
The boss portion is connected to the rotating shaft, and attached to the outer peripheral side of the boss portion, or integrated with the outer peripheral side of the boss portion. A preparation step of providing the pulley layout in such a manner that the arc portion connecting the outer edges of the grooves formed on the outer circumference of some of the split pulleys stays in the inner region of the circumference of the pulley layout including the toothed pulley;
a suspension step of suspending the toothed belt on the pulley layout provided in the preparation step;
a tension applying step of rotating the toothed pulley including the partial split pulley and applying tension to the toothed belt when it is worn;
and an assembly step of attaching the remaining split pulley to the outer peripheral side of the boss portion via the fixing means.

According to the above method, even if a toothed belt with a relatively high belt elastic modulus is attached to a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.) , the tension of the toothed belt can be set at a relatively high level.

It is a perspective view of the toothed pulley of this embodiment (Example 1). It is a 6-sided view of the toothed pulley of this embodiment (Example 1). It is an exploded view of the toothed pulley of this embodiment (Example 1). It is a perspective view of a 1st split pulley (Example 1). 1 is a perspective view of a belt mounting pulley (toothed pulley with a first split pulley attached to a base member) (Embodiment 1); FIG. (A) It is a figure explaining the preferable fitting form of a 1st division|segmentation pulley and a base member. (B) It is a figure explaining the unpreferable fitting form of a 1st division|segmentation pulley and a base member. 1 is a partial perspective view of a toothed belt used in a synchronous transmission belt system of Examples and Comparative Examples; FIG. It is explanatory drawing of the shape of the tooth part of a toothed belt. FIG. 4 is a schematic diagram showing a preparatory step in the synchronous transmission belt system using the toothed pulleys of the present embodiment (Example 1). FIG. 4 is a schematic diagram showing a suspension step state in the synchronous transmission belt system using the toothed pulleys of the present embodiment (Example 1). FIG. 10 is a schematic diagram showing the state of a tension applying step in the synchronous transmission belt system using the toothed pulley of the present embodiment (Example 1). FIG. 10 is a schematic diagram showing the state of a tension applying step in the synchronous transmission belt system using the toothed pulley of the present embodiment (Example 1). FIG. 4 is a schematic diagram showing a state of an assembly step in the synchronous transmission belt system using the toothed pulleys of the present embodiment (Example 1). It is a schematic diagram showing the state of (A) preparation step, (B) tension application step, and (C) assembly step in the synchronous transmission belt system using the toothed pulley of another embodiment (Example 2). . It is a schematic diagram showing the state of (D) tension application step and (E) assembly step in the synchronous transmission belt system using the toothed pulley of another embodiment (Example 2). FIG. 10 is a schematic diagram showing the state of a preparation step and an assembly step in a synchronous transmission belt system using toothed pulleys of another embodiment (Example 3). It is a 6-sided view of a toothed pulley of another embodiment (Example 2). It is a 6-sided view of a toothed pulley of another embodiment (Example 3). It is a perspective view of the conventional (comparative examples 1 and 2) toothed pulley. (A) A schematic diagram of a synchronous transmission belt system using a conventional (comparative example 1) toothed pulley. (B) It is a figure explaining the subject (problem) of the conventional (comparative example 2) toothed pulley.

(embodiment)
Hereinafter, a toothed pulley 1 according to an embodiment of the present invention (Example 1 described later), a synchronous transmission belt system 100 including the toothed pulley 1, and a toothed belt 2 in the synchronous transmission belt system 100 will be described.

(Toothed pulley 1)
The toothed pulley 1 is, as shown in FIG. is.

As shown in FIG. 3, the toothed pulley 1 is attached to the outer peripheral side of the boss portion 111, and has a shape divided into two in the circumferential direction of the boss portion 111, namely, a first split pulley 12 and a second split pulley. It has a structure including a pulley 13 and a base member 11 (corresponding to fixing means) for fixing the positional relationship of the first split pulley 12 and the second split pulley 13 in the rotation axis direction. The first split pulley 12 can be attached to the outer peripheral side of the boss portion 111 while the second split pulley 13 is not attached to the outer peripheral side of the boss portion 111 . That is, the toothed pulley 1 can maintain a state in which only the first split pulley 12 is attached to the outer peripheral side of the boss portion 111, as shown in FIG.

(First split pulley 12 and second split pulley 13)
In this embodiment, the configuration includes the first split pulley 12 and the second split pulley 13 which are divided into two in the circumferential direction of the boss portion 111, but the number of divisions may be three or four. good. However, the number of divided pulleys is preferably two as shown in this embodiment (see FIG. 3). When the number of divided pulleys is two, compared with the case where the number of divisions (the number of divided pulleys) is 3 or more, the manufacturing time and effort of the toothed pulley 1 and the toothed pulley 1 of the toothed belt 2 are reduced. It is possible to reduce the trouble of mounting between the driven pulley 102 and the trouble of assembling the split pulley to the base member 11.例文帳に追加

Further, the dividing surface 12a of the first dividing pulley 12 and the dividing surface 13a of the second dividing pulley 13 may be formed so as to extend along the radial direction of the toothed pulley 1 as in the present embodiment (see FIG. 3). ), it may be formed including a surface extending in a direction inclined with respect to the radial direction of the toothed pulley 1 .

Further, the groove portion 1 formed on the outer circumference of the first split pulley 12 and the outer circumference of the second split pulley 13
4 has a shape extending in the rotation axis direction. That is, straight teeth are formed on the outer periphery of the first split pulley 12 and the outer periphery of the second split pulley 13 (for example, a shape corresponding to a general straight tooth (suguba)).

The shape of the groove portion 14 may be formed in a shape corresponding to the tooth shape of the toothed belt 2 to be mounted as long as synchronous transmission (meshing transmission) is possible. It may have a shape extending in an inclined direction (for example, a shape corresponding to a helical tooth (tooth with an oblique contact angle on the tooth surface)).

Here, as in the present embodiment, when the grooves 14 formed on the outer circumference of the first split pulley 12 and the outer circumference of the second split pulley 13 have a straight tooth shape extending in the direction of the rotation axis, When the belt 2 is mounted, the edge (corner portion C) on the outer peripheral side of the dividing surface 12a of the first split pulley 12 and the dividing surface 13a of the second split pulley 13 is prevented from being damaged due to contact with the toothed belt 2. and from the viewpoint of improving the wearability of the toothed belt 2 (workability in the assembly step described later), the first split pulley 12 and the second split pulley 13 are provided with grooves as shown in FIG. 14 is divided in the circumferential direction at the bottom surface 14a. That is, as shown in FIG. 2, the first split pulley 12 and the second split pulley 13 are split at the plane connecting the bottom surfaces 14a facing each other. As described above, the shape of the groove portion 14 is preferably a straight tooth, which is a shape that easily serves as the starting point of the dividing surface 12a and the dividing surface 13a on the bottom surface 14a.

Even if the shape of the groove portion 14 is a helical tooth, by chamfering the edge (corner portion C) on the outer peripheral side of the dividing surface 12a and the dividing surface 13a, when the toothed belt 2 is attached, the dividing surface 12a Also, damage to the toothed belt 2 due to contact with the edge (corner portion C) on the outer peripheral side of the dividing surface 13a can be suppressed to some extent.

When the first split pulley 12 and the second split pulley 13 are divided in the circumferential direction at a portion other than the bottom surface 14a of the groove portion 14 (for example, a portion facing the tooth root portion and the tooth bottom portion of the toothed belt 2). When the toothed belt 2 is mounted on the pulley layout (temporary mounting) using the toothed pulley 1 as a belt mounting pulley in a state where only the first split pulley 12 is attached to the base member 11, In the process in which tension is applied to the belt 2, the portion of the toothed belt 2 having a relatively thin thickness other than the tooth portion 21 (tooth root portion and tooth bottom portion) becomes the outer peripheral end portion (corner portion C) of the dividing surface 12a. ), the toothed belt 2 may be bent and cracked or broken.

However, according to the above configuration, the dividing surface 12a and the dividing surface 13a are formed starting from the bottom surface 14a of the groove 14, and the toothed pulley 1 is divided in the circumferential direction. Since it is the tip portion of the toothed belt 2 that comes into contact with the edge (corner portion C) on the outer peripheral side of the dividing surface 12a when it is mounted, it is possible to prevent the above problems (cracks, etc.) from occurring.

(Base member 11)
The base member 11 has a structure in which a boss portion 111 and a circular flange 112 extending radially outward from one side of the boss portion 111 are integrally formed. A groove 111a is formed on the inner periphery of the boss portion 111 so as to engage the rotating shaft with a keyway so that the rotating shaft and the toothed pulley 1 can be fixed so as not to rotate relative to each other. The flange 112 extends from one side of the boss portion 111 to at least the outer edge of the groove portion 14 in a state where the first split pulley 12 and the second split pulley 13 are attached. It has a shape slightly larger than the outer edges of the pulley 12 and the second split pulley 13 (see FIG. 2).

Eight holes 114 are formed in an annular shape on the outside of the boss portion 111 in the flange 112 . By fastening the four holes 12b (see FIG. 4) formed in the first split pulley 12 and the four holes 114 formed in the flange 112 through rivets or screw members (corresponding to fastening members), the flange 112 , the first split pulley 12 can be fixed. Similarly, by fastening four holes 13b (not shown) formed in the second split pulley 13 and four holes 114 formed in the flange 112 through rivets or screw members, the second split pulley 112 is provided with a second split pulley. The pulley 13 can be fixed. In this way, by enabling the first split pulley 12 and the second split pulley 13 to be fixed to the flange 112 through the rivets and screw members, the first split pulley 12 and the second split pulley 12 and the second split pulley 13 can be fixed on the outer peripheral side of the boss portion 111 of the base member 11 . The positional relationship of the two-split pulley 13 in the rotation axis direction can be fixed more reliably. In addition, the degree of freedom in designing (configuration) of the toothed pulley 1 can be increased.

As a means for fixing the flange 112 and the first split pulley 12, or the flange 112 and the second split pulley 13, for example, the rotating shaft and the boss portion 111 are fitted in a keyway so as to be fixed so as not to rotate relative to each other. As in the configuration, the second split pulley 13 and the boss portion 111 are fitted in a keyway so that they cannot rotate relative to each other, and are fastened with a rivet or a screw member so that the first split pulley 12 and the second split pulley 12 are adjacent to each other in the circumferential direction. A configuration may be employed in which the positional relationship of the split pulleys 13 is fixed (not shown).

(Spigot structure)
As shown in FIGS. 3 and 4 , the first split pulley 12 has a semi-annular projection 12 c formed on the side facing the flange 112 . Similarly, in the second split pulley 13, a semi-annular convex portion 13c is formed on the side surface facing the flange 112. As shown in FIG. On the other hand, as shown in FIG. 3 , an annular concave portion 113 is formed along the outer periphery of the boss portion 111 on the side surface of the flange 112 facing the first split pulley 12 and the second split pulley 13 . Then, the convex portion 12c of the first split pulley 12 and the concave portion 113 of the flange 112 are concentrically fitted, and similarly, the convex portion 13c of the second split pulley 13 and the concave portion 113 of the flange 112 are concentrically fitted. is considered possible. That is, the first split pulley 12 and the flange 112 and the second split pulley 13 and the flange 112 have a spigot joint structure. As a result, the toothed pulley 1 (final shape) after the first split pulley 12 and the second split pulley 13 are attached to the base member 11 has exactly the same external shape (annular shape) and function as a normal toothed pulley. A toothed pulley having a higher dimensional accuracy can be obtained.

Note that the protrusions and recesses of the spigot joint structure may be arranged in reverse. That is, in the first split pulley 12 and the second split pulley 13, a semi-annular recess is formed in the side surface facing the flange 112, and the flange 112 faces the first split pulley 12 and the second split pulley 13. A spigot structure in which an annular projection is formed on the side surface may be used. However, if a convex portion is formed on the flange 112 side, the toothed belt 2 is attached to the pulley layout using the toothed pulley 1 in which only the first split pulley 12 is attached to the outer peripheral side of the boss portion 111. When doing so (temporarily hanging), especially in the process of applying tension to the toothed belt 2, as shown in FIG. There is a risk that the toothed belt 2 will be damaged. Therefore, as in the present embodiment, when the concave portion 113 is formed on the flange 112 side (see FIG. 6A), since there is no convex portion projecting from the flange 112, the toothed belt 2 can be arranged in a pulley layout. The toothed belt 2 will not be damaged when it is attached to the belt.

The spigot structure between the first split pulley 12 and the flange 112 and between the second split pulley 13 and the flange 112 are not essential, and the spigot structure may not be used (not shown).

(Materials used for toothed pulley 1)
The material of the toothed pulley 1 (each component of the base member 11, the first split pulley 12, and the second split pulley 13) is not particularly limited. Metals such as iron, iron alloys, aluminum alloys, etc., or resins (cast nylon resins, etc.) may be used. From the viewpoint of suppressing thermal expansion (dimensional change) due to temperature change, it is preferable to use an iron alloy (for example, a nickel-iron alloy) having a relatively small coefficient of linear expansion.

(Manufacturing method of toothed pulley 1)
The toothed pulley 1 (each component of the base member 11, the first split pulley 12, and the second split pulley 13) is processed by machining (cutting, etc.), cold forging, hot forging, and die casting (die casting). etc.), powder metallurgy (a method of sintering a green compact obtained by compression-molding metal powder), or a known method using these together.

As for the first split pulley 12 and the second split pulley 13, the first split pulley 12 and the second split pulley 13 may be individually manufactured by the above method. From the viewpoint of ensuring a higher level of manufacturing quality (outer diameter roundness, etc.) of the toothed pulley 1 including the It is preferable to divide the pulley into two parts, the first split pulley 12 and the second split pulley 13, by using a cutting method such as laser machining or ultrasonic machining.

(Synchronous transmission belt system 100)
The synchronous transmission belt system 100 has a pulley layout in which the toothed belt 2 is wound around two or more toothed pulleys, and at least one of the two or more toothed pulleys is the toothed pulley 1 . The number of toothed pulleys 1 according to the present embodiment used in a synchronous transmission belt system having a plurality of toothed pulleys may be two or more, but preferably one.

Specifically, as shown in FIG. 13, the synchronous transmission belt system 100 of this embodiment includes a drive pulley 101 (toothed pulley 1) and a driven pulley 102 (conventional toothed pulley) which are spaced apart (fixed in position). pulleys), and the toothed pulley 1 of the present embodiment is used as the drive pulley 101 .

As shown in FIG. 5, the toothed pulley 1 is mounted on the flange 112 with only the first split pulley 12 attached (only the first split pulley 12 is attached to the outer peripheral side of the boss portion 111). , and functions as a belt mounting pulley used when mounting the toothed belt 2 between the drive pulley 101 (toothed pulley 1 ) and the driven pulley 102 . From another point of view, the toothed pulley 1 rotates around the rotating shaft in a state in which the second split pulley 13 is not attached to the flange 112 (a state in which the second split pulley 13 is not attached to the outer peripheral side of the boss portion 111). attached to the belt and used as a belt attachment pulley. Specifically, before mounting the toothed belt 2 between the drive pulley 101 (toothed pulley 1) and the driven pulley 102, as shown in FIG. A circular arc portion 12 d connecting the outer edges of the groove portion 14 formed on the outer periphery of the pulley 12 is arranged in a manner to remain in the inner region of the circumference of the pulley layout including the toothed pulley 1 .

(Toothed belt 2)
As shown in FIG. 7, the toothed belt 2 used in the synchronous transmission belt system 100 has a back portion 23 in which a core wire 22 is embedded, and arranged on one surface of the back portion 23 at predetermined intervals along the longitudinal direction of the belt. and a tooth cloth 24 covering the inner peripheral side of the toothed belt 2 including the toothed portions 21 .

(Core wire 22)
The core wire 22 is embedded in the back portion 23 of the toothed belt 2 . The core wire 22 is composed of a twisted cord formed by twisting a plurality of strands. A single strand may be formed by bundling and arranging filaments (long fibers).

When the core wire 22 is required to have a relatively high belt elastic modulus (for example, about 200 to 400 KN) as in the present embodiment, the material of the filament should be high strength and low elongation such as high strength glass fiber. The thickness of the filament, the number of bundled filaments, the number of strands, and the twist configuration such as the twisting method are appropriately selected, and the core wire 22 (twisted cord) is made to have a thickness (for example, 1 mm) that matches the target elastic modulus of the belt. diameter). The twisted cord used as the core wire 22 is preferably subjected to adhesion treatment in order to increase adhesion to the spine 23. For example, after being immersed in a resorcinol-formalin-latex treatment solution (RFL treatment solution), it is dried by heating. Then, an adhesive treatment is performed by a method of forming an adhesive layer uniformly on the surface.

(Rubber-like elastic body forming back portion 23 and tooth portion 21)
The rubber-like elastic body forming the back portion 23 and tooth portions 21 of the toothed belt 2 is formed by cross-linking a rubber composition. The rubber components of this rubber composition include chloroprene rubber (CR), nitrile rubber, hydrogenated nitrile rubber (HNBR), ethylene-propylene copolymer (EPM), ethylene-propylene-diene terpolymer (EPDM). , styrene-butadiene rubber, butyl rubber, chlorosulfonated polyethylene rubber and the like are used. These rubber components can be used alone or in combination. Although details are omitted, the rubber composition constituting the back portion 23 and the tooth portion 21 may contain carbon black, a plasticizer, a cross-linking agent, and other conventional additives (or compounding agents) as necessary. It is prepared by blending.

(Tooth cloth 24)
The tooth cloth 24 covering the surface of the tooth portion 21 and a part of one surface of the back portion 23 (that is, the surface of the tooth bottom portion 21a of the tooth portion 21) is made of aliphatic polyamide fiber such as 6 nylon, 6,6 nylon ( A woven fabric made of nylon fiber) that has undergone an adhesive treatment is generally used. In this case, as the tooth cloth 24, the warp (in the width direction of the belt) is 6 nylon, and the weft (in the longitudinal direction of the belt) is elastic yarn having elasticity (urethane elastic yarn whose material itself is elastic, or the fiber is stretched). A fiber woven fabric with a twill weave structure is used, which is made of 6 nylon including woolly processing). A tooth cloth 24 obtained by immersing the above fiber fabric in an RFL liquid is used. The thickness of the tooth cloth 24 (the thickness of the cross section of the toothed belt 2) is, for example, about 0.2 mm. It should be noted that the tooth cloth 24 is not limited to the one described above. The fiber fabric used as the tooth cloth 24 may be made of a material such as polyester or aramid fiber alone or in combination depending on the load of each belt system.

(Tooth shape of tooth portion 21)
As long as synchronous transmission (meshing transmission) is possible, the tooth shape of the tooth portion 21 is a helical tooth (a tooth with an oblique contact angle on the tooth surface) even in a tooth shape called a general straight tooth (Suguba). A tooth shape called . The toothed belt 2 used in the synchronous transmission belt system 100 of this embodiment has straight teeth.

As the tooth shape belonging to the straight teeth, it is possible to select a tooth shape suitable for the use of the belt system, such as the following known tooth shapes, modified shapes thereof, special shapes, and the like. For example, the H tooth profile, which has a substantially semicircular cross section, the T tooth profile, which has a trapezoidal cross section, and the S tooth profile (STPD type), each of which consists of an outwardly bulging convex curved surface (arc surface). A shape in which two side surfaces are connected by a flat surface (see FIG. 8) can be mentioned.

(Belt reference circumference)
First, terms used in the following description will be explained.
The tension at the time of installation refers to the tension applied to the belt in the longitudinal direction immediately after the belt is installed on the pulley layout.
The pulley layout circumference is a line (pulley layout circumference) ( That is, it refers to the length of the belt path.
The reference circumferential length of the belt means that the belt is wound around and stretched between two flat pulleys (pulleys without grooves on the outer circumferential surface) with the toothed surface facing outward. and the tension to the extent that the deflection in the longitudinal direction of the belt is removed (in the case of a toothed belt with a belt width of 20 mm used in the evaluation of the example, the tension to the extent that the deflection in the longitudinal direction of the belt is removed) The level of is the length in the longitudinal direction of the belt when about 100 N) is applied to the belt.

The reference circumferential length (L0) of the toothed belt 2 of the present embodiment includes (1) belt elastic modulus (belt tensile rigidity), (2) tension at the time of installation, and (3) after belt installation (after application of tension at the time of installation). Depending on the belt circumference (L) (pulley layout circumference (L2)), the above (3) belt circumference (L) after belt installation (after application of tension during installation) (pulley layout circumference after belt installation ( It is determined by estimating the shortened length (shortened length ratio) from (corresponding to L2)).

For example, the synchronous transmission belt system 100 has a belt width of 20 mm, (1) a belt elastic modulus of about 200 to 400 KN, (2) a tension of about 200 to 400 N when worn, and (3) after belt attachment (tension applied when attached). rear) belt circumference (L) (equivalent to the pulley layout circumference (L2) after belt installation) is 840 mm, the measurement history (data) of the belt elastic modulus for each belt type, that is, the belt tension T ( N) and the stress-strain curve (SS diagram) showing the relationship between the belt elongation amount (L-L0) (mm), shortening from the belt circumference (L) after mounting between the pulleys Since the length (shortened length rate) is estimated to be about 0.4 mm (0.05%) to 0.8 mm (0.1%), the reference circumferential length (L0) of the toothed belt 2 (the length of the belt (corresponding to the belt circumference when tension is applied to remove the deflection in the direction) is determined to be about 839.2 mm to 839.6 mm.

(belt elastic modulus)
The belt elastic modulus of the toothed belt 2 is about 200 to 400 KN with a belt width of 20 mm, which is a level that can be used for applications with a higher load. If the elastic modulus of the belt is less than 200 kN, the phase shift angle between the rotation axis of the driving pulley 101 and the rotation axis of the driven pulley becomes large (for example, greater than 2°), which may impair synchronism. On the other hand, if the elastic modulus of the belt exceeds 400 kN, when the synchronous transmission belt system 100 is used in a belt system in which the main body of the system thermally expands, such as for an automobile engine, the belt tension due to the change in the center distance may be excessively increased. The running of the belt accelerates bending fatigue of the core wire or wear of the tooth cloth, and there is a possibility that the durability of the belt is reduced early. Here, the elastic modulus of the belt is measured by the following method.

(Method for measuring elastic modulus of belt)
A pair of pulleys (30 teeth) are attached to the lower fixing portion and the upper load cell connecting portion of an autograph (for example, "AGS-J10kN" manufactured by Shimadzu Corporation), and the toothed belt 2 is hung between the pulleys. Next, the upper pulley is raised, and an initial tension T0 (about 100 N) is applied to the extent that bending of the toothed belt 2 in the longitudinal direction is removed. The position of the upper pulley in this state is assumed to be the initial position, and the belt circumference at this time is the belt reference circumference (L0) (mm), and the upper pulley is raised at a speed of 10 mm/min. A region ( straight part), the increase (T - T0) (N) of the belt tension T (N) from the initial tension state is calculated as the ratio of the belt elongation amount (L - L0) to the belt reference circumference (L0) [ (L−L0)/L0] (dimensionless) to calculate the value (N) (corresponding to the so-called “belt tension stiffness”), which is defined as the belt elastic modulus (N).

(Tension when installed)
The level of tension required for the toothed belt 2 capable of coping with higher-load applications, which is the purpose of the present application, is given to the belt when an auto tensioner commonly used in the belt system as a tension applying mechanism operates. When the belt width is 20 mm, it is about 200 to 400 N. If the tension at the time of attachment is less than 200 N, the transmission capacity of the belt under high load will be hindered, and problems such as tooth jumping may occur under high load. On the other hand, if the tension exceeds 400 N, the belt runs with an excessively increased belt tension, which promotes bending fatigue of the cord or wear of the tooth cloth, and early deterioration of the durability of the belt. There is fear.

For example, in the process of assembling an engine, by human hands (without jigs), a belt with a tooth width of 20 mm is used for a two-shaft layout with a fixed inter-shaft distance, which is composed of one drive pulley and one driven pulley. In the case of a work mode in which an attached belt is attached, the upper limit level of tension at the time of attachment that can be attached by human hands (without jigs) is at most about 100N.

(How to use the toothed pulley 1 as a belt-mounting pulley)
(1) First, the pulley layout circumference (L2) after the belt is installed is longer than the belt reference circumference (L0) (for example, 0.5 to 100 N) depending on the required level of tension when the belt is installed (for example, about 200 to 400 N). 05 to 0.1% longer), the rotating shaft of the toothed pulley 1 (driving pulley 101) and the rotating shaft of the driven pulley 102 are fixed between the shafts (pulley layout with a fixed shaft distance) .

(2) Connect the driven pulley 102 to the rotating shaft. Next, the base member 11 to which the first split pulley 12 is attached (or the first split pulley 12 may be integrally formed with the base member 11) is attached to the rotating shaft of the toothed pulley 1 (drive pulley 101). connect to. That is, when the toothed belt 2 is mounted between the toothed pulley 1 (driving pulley 101) and the driven pulley 102 with the toothed pulley 1 in which the second split pulley 13 is not attached to the base member 11, It is connected to the rotating shaft of the toothed pulley 1 (driving pulley 101) as the belt mounting pulley to be used.

As shown in FIG. 9, when viewed in the rotational axis direction of the toothed pulley 1, an arc portion 12d connecting the outer edges of the grooves 14 formed on the outer circumference of the first split pulley 12 serves as a belt attachment pulley. Circumference of the pulley layout including the toothed pulley 1 (to the outer circumference of the toothed pulley 1 as the belt mounting pulley and the driven pulley 102 so as to connect the outer circumference of the toothed pulley 1 as the belt mounting pulley and the driven pulley 102 The toothed pulley 1 as a belt-mounting pulley is rotated so as to remain in the inner region of the line formed annularly along the belt. With such a pulley layout, the circumference (L1) of the pulley layout before the belt is attached can be shortened in advance with respect to the belt reference circumference (L0) (preparatory step: FIG. 9).

(3) Next, the toothed belt 2 is wound between the toothed pulley 1 as a belt mounting pulley and the driven pulley 102 . As a result, the toothed belt 2 having a relatively high elastic modulus can be easily suspended on the pulley layout including the toothed pulley 1 as the belt mounting pulley (suspension step: FIG. 10).

(4) Next, as shown in FIG. 11, using the principle of leverage as necessary (for example, by connecting an L-shaped tool such as a hexagonal wrench to the end of the rotation shaft of the toothed pulley 1), , to rotate the toothed pulley 1 as a belt-mounting pulley. Specifically, as shown in FIG. 12, the toothed pulley 1 as the belt-mounting pulley is rotated halfway. By rotating the toothed pulley 1 as the belt mounting pulley to a substantially overlapping position, the pulley layout circumferential length (L2) after belt mounting is lengthened (for example, 0.05) with respect to the belt reference circumferential length (L0). about 0.1% longer). Therefore, the toothed pulley 1 as the belt mounting pulley functions as a tension applying mechanism when the toothed belt 2 is mounted between the toothed pulley 1 (driving pulley 101) and the driven pulley 102 ( Tensioning step: Figures 11, 12).

(5) Finally, as shown in FIG. 13, while applying the second split pulley 13 to the boss portion 111 and the first split pulley 12, the second split pulley 13 is rotated in a direction parallel to the rotation axis. By fitting the convex portion 13 c into the concave portion 113 of the flange 112 and fastening the second split pulley 13 and the flange 112 with a rivet or a screw member, the second split pulley 13 is attached to the boss portion 111 via the base member 11 . attached to the outer circumference of the That is, the toothed pulley 1 is formed by integrating the base member 11 , the first split pulley 12 , and the second split pulley 13 . As a result, the toothed pulley 1 as the drive pulley 101, which has exactly the same external shape (annular shape) and functions as those of a normal toothed pulley, can be applied to the synchronous transmission belt system 100 (assembly step: FIG. 13).

According to the above configuration, when the toothed belt 2 having a relatively high belt elastic modulus is attached to a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.) Also, the tension when the toothed belt 2 is worn can be set to a relatively high level.

(Other embodiments)
(1) In the above embodiment, the first split pulley 12 and the base member 11 are configured to be attachable as separate members, but the first split pulley 12 and the base member 11 are integrated into one member. (belt mounting pulley in the state of FIG. 5). That is, in a state in which the first split pulley 12 is fixed to the outer peripheral side of the boss portion 111, the first split pulley 12, the boss portion 111, and the flange 112 are integrally formed (not disassembled), and are connected via rivets and screw members. , the second split pulley 13 may be fixed.

(2) In the above embodiment, the flange 112 is provided only on one side surface of the toothed pulley 1, but may be provided on the other side. For example, in the first split pulley 12 and the second split pulley 13 , a flange extending at least to the outer edge of the groove 14 may be formed on the side opposite to the side facing the flange 112 . That is, the toothed pulley 1 may have a flange 112 only on one side (single-flanged pulley), or may be provided with the flange 112 provided on the base member 11 (double-flanged pulley). In the latter configuration (dual-flanged pulley), it is possible to reliably prevent the toothed belt 2 from coming off the toothed pulley 1 .

(3) In the above embodiment, the central angle α (α=180°) of the circular arc portion 12d of the first split pulley 12 as seen in the rotation axis direction is the winding angle of the toothed belt 2 with respect to the toothed pulley 1 ( The central angle α of the circular arc portion 12d is the inner region of the circumference of the pulley layout including the toothed pulley 1 as the belt mounting pulley when viewed in the rotation axis direction. The circumferential length (L1) of the pulley layout is made shorter than the belt reference circumferential length (L0) of the toothed belt 2 in the state where the circular arc portion 12d is provided in a fixed state.

As an embodiment of the present invention, as shown in FIG. 14A, the central angle α of the arc portion 12d of the first split pulley 12 may be less than the winding angle.
In this case, the remaining second split pulley 13 is further divided into a plurality (2 or 3) from the viewpoint of improving the assembling workability of the remaining split pulleys (simplifying the work in the assembling step). The configuration (see FIG. 15(E)) is desirable (in FIGS. 14 and 15, the second split pulley 13 is further split into a second split pulley 131 and a second split pulley 132). Furthermore, the groove portion 14 of the toothed pulley 1 has a shape corresponding to straight teeth, and the distance (span length) between the toothed pulley 1 (driving pulley 101) and the driven pulley 102 via the toothed pulley 1 is compared. It is desirable to apply to a long pulley layout. Furthermore, it is applied to a synchronous transmission belt system in which the winding angle of the toothed pulley 1 (driving pulley 101) is smaller than 180° (for example, a two-axis layout in which the diameter of the driven pulley 102 is larger than the diameter of the driving pulley 101). It is desirable to

However, from the viewpoint of improving the assembling workability (workability in the assembling step) of the second split pulley 13, the central angle α of the circular arc portion 12d of the first split pulley 12 when viewed in the direction of the rotation axis should be The central angle α of the arc portion 12d is equal to or greater than the attachment angle, and the arc portion 12d stays in the inner region of the circumference of the pulley layout including the toothed pulley 1 as the belt mounting pulley when viewed in the rotation axis direction. It is preferable that the circumferential length (L1) of the pulley layout is within a range that is less than the belt reference circumferential length (L0) of the toothed belt 2. In this case, a synchronous transmission belt system in which the winding angle of the toothed pulley 1 (driving pulley 101) is greater than 180° (for example, a biaxial layout in which the diameter of the driven pulley 102 is smaller than the diameter of the driving pulley 101). can also be applied.

In other words, the effect (size) of being able to change the pulley layout circumference (L) before and after the belt is attached and the assembling workability of the remaining second split pulley 13 (workability in the assembling step) are compatible. From the viewpoint of doing so, the central angle α of the circular arc portion 12d of the first split pulley 12 is set in an angle range that is the same as the winding angle (the above embodiment: FIG. 13) or slightly larger as shown in FIG. 16(A). is more preferred.

As shown in FIG. 14A, when the central angle α of the circular arc portion 12d of the first split pulley 12 is set to be less than the winding angle, the number of the remaining second split pulleys 13 is one (unnecessary). ), in the assembling step, while the second split pulley 13 is applied to the boss portion 111 and the first split pulley 12, the convex portion 13c of the second split pulley 13 is moved along the direction parallel to the rotation axis. is fitted into the concave portion 113 of the flange 112 , the work must be performed while the toothed belt 2 is pushed outward in the radial direction of the toothed pulley 1 against the tension of the toothed belt 2 . Therefore, the workability of assembling the second split pulley 13 to the base member 11 may be hindered.
Therefore, when the central angle α of the arc portion 12d of the first split pulley 12 is set to be less than the winding angle, the workability of assembling the second split pulley 13 to the base member 11 (workability in the assembling step) is reduced. In order to prevent obstruction, although details will be described later, the remaining second split pulley 13 is further divided into a plurality (2 to 3) (see FIG. 15 (E)), and in the assembly step , while applying the second split pulley 13 to the boss portion 111 and the first split pulley 12, the convex portion 13c of the second split pulley 13 is fitted into the concave portion 113 of the flange 112 along the direction parallel to the rotation axis. For each rotation angle of the toothed pulley 1 as a pulley for belt mounting, the toothed belt 2 does not have to be spread radially outward of the toothed pulley 1 against the tension of the toothed belt 2 when the toothed belt 2 is turned on. , the tension applying step and the assembling step are preferably repeated step by step (for example, divided into two steps as shown in FIGS. 14(B) to 15(E)).

On the other hand, as shown in the present embodiment (see FIGS. 9 to 13) and FIG. As long as the central angle α of the circular arc portion 12d is provided within a range in which the circumferential length (L1) of the layout is less than the belt reference circumferential length (L0) of the toothed belt 2, the remaining second split pulley Even if the pulley 13 is not divided into a plurality of parts (2 to 3), the assembling workability of the second split pulley 13 (workability in the assembling step) is not hindered.

(4) In the above embodiment, the toothed pulley 1 is used as the driving pulley 101, but the toothed pulley 1 can be applied to either the driving pulley 101 and/or the driven pulley 102 in the synchronous transmission belt system 100. may However, in a synchronous transmission belt system 100 (pulley layout) having multiple (two or more) pulleys, it is preferred that only one pulley is the toothed pulley 1 described above. In this case, the manufacturing cost of the synchronous transmission belt system 100 (especially the pulley layout) and the effort of mounting the toothed belt 2 on the pulley layout can be minimized.

In the toothed pulley of the present invention, even when a belt having a relatively high belt elastic modulus is attached to a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.) The belt must be able to be mounted between the pulleys so that the belt tension can be set to a relatively high level.

Therefore, in this example, toothed pulleys (hereinafter referred to as test pieces) according to Examples 1 to 3 and Comparative Examples 1 and 2 were produced, and the tension when the belt was attached was measured for comparison and verification. Although the present invention will be described in more detail below based on examples, the present invention is not limited to these examples.

[Toothed pulley]
(Common to each specimen)
・The toothed pulleys of Example 1 (Fig. 2), Example 2 (Fig. 17), Example 3 (Fig. 18), and Comparative Examples 1 and 2 (Fig. 19) all have straight teeth with 30 teeth. A pulley was used.
・Material used: Iron alloy (nickel-iron alloy).
・Manufacturing method of pulley: Manufactured by machining (cutting, etc.). In addition, multiple (two or three) split pulleys are manufactured in an integrated shape (without splitting) in the same way as a normal toothed pulley, and then cut into multiple split pulleys by wire-cut electrical discharge machining. applied and produced.

(Examples 1 to 3: FIGS. 1, 2, 17, and 18)
(multiple split pulleys)
Number of split pulleys and central angle α of circular arc part: 2 in Example 1 (two with α = 180 °), 3 in Example 2 (one with α = 84 °, α = 1 for 96°, 1 for α = 180°), 2 for Example 3 (1 for α = 84°, 1 for α = 276°)
・The dividing surface was formed so as to extend along the radial direction of the toothed pulley.
・Each split pulley is split in the circumferential direction at the bottom of the groove.

(Base member 11)
・The base member has a structure in which a boss portion and a circular flange extending radially outward from one side of the boss portion are integrally formed. member) (not shown).
The flange has a plurality of through-holes (8 places) through which fastening members (bolts) can be inserted. A plurality (2 to 6 locations each) are formed as many as possible.
• The flange extends from one side of the boss to at least the outer edge of the groove (specifically, a position where the entire back side of the toothed belt can abut).
- The split pulley and the base member have a spigot structure (the protrusion on the split pulley side and the recess on the base member side can be concentrically fitted).

(some split pulleys)
・With the above configuration, one (part) of the multiple (two or three) split pulleys (one) is the base member, and the other (remaining) split pulley (one or two) is the base member. (the other (remaining) split pulley is not attached to the outer peripheral portion of the boss), and can be formed integrally with the base member (boss) (that is, connectable to the rotating shaft). It is configured.

(Comparative Examples 1 and 2: Fig. 19)
・The toothed pulleys of Comparative Examples 1 and 2 were formed with a boss configured to be connectable to the rotating shaft, and a groove that meshes with the teeth of the toothed belt on the outer peripheral side of the boss. A toothed pulley was used.
- The outer peripheral portion of the boss portion does not have a shape that is divided into a plurality of parts in the circumferential direction.

[Synchronous transmission belt system]
(Common to each specimen)
(Toothed belt: Fig. 8)
・Name of toothed belt: 105S8M20
Shape of tooth portion: The tooth shape was S8M with a tooth pitch of 8 mm (STPD type) belonging to a straight tooth (see FIG. 8).
Number of teeth: 105
Tooth pitch: 8mm
belt width 20mm
・Belt reference circumference (L0): 839.37 mm (the belt tension applied at this time is about 100 N)
・Belt elastic modulus: 285KN
Calculation formula: (T-T0) / [(L-L0) / L0],
(312N-98N)/[(840.00-839.37)mm/839.37mm]
= 285KN

・Materials used (rubber-like elastic body that constitutes the back and teeth)
- Rubber component of rubber composition: Hydrogenated nitrile rubber (HNBR)
・Composition of rubber composition: See Table 1

(tooth cloth)
・Construction: See Table 2 ・Thickness of tooth cloth (thickness at cross section of belt): 0.2 mm

(Core wire)
・Configuration: Table 3

・The core wire (twisted cord) was prepared by the following procedure.
600 high-strength glass fiber (K glass fiber) filaments (diameter of 7 microns) with the designation KCE-225 described in JIS R 3413 (2012) were bundled and aligned to form three strands. The three strands are immersed in an RFL liquid (18 to 23 ° C.) having the composition shown in Table 4 for 3 seconds, and then dried by heating at 200 to 280 ° C. for 3 minutes to form a uniform adhesive layer on the surface. formed. After this bonding treatment, three strands are first twisted at a twist number of 12 times/10 cm, 11 strands are aligned, and twisted (ply twist) at a twist number of 8 times/10 cm in the opposite direction to the first twist. , a twisted cord having a diameter of about 0.9 mm was prepared.

(Manufacturing method of toothed belt)
・First, a rubber composition having the composition shown in Table 1 was kneaded in a Banbury mixer, and the kneaded rubber was passed through a calender roll to form a rolled rubber sheet having a predetermined thickness. A sulfur rubber sheet was produced.
The hardness of the vulcanized rubber sheet obtained by press vulcanizing the prepared rubber composition (unvulcanized rubber sheet) at 165 ° C for 30 minutes is the type A durometer hardness (JIS K6253: 2012 compliant) was about 70.
- Subsequently, a woven fabric used as a tooth cloth having the configuration shown in Table 2 was woven, immersed in the RFL liquid shown in Table 4, dried, and heat-treated, and the same rubber composition as the unvulcanized rubber sheet shown in Table 1. Adhesion treatment was performed by immersing the object in a rubber paste dissolved in a solvent and drying it.
・Using each of the above-mentioned materials used, cord (adhesive treated product), tooth cloth (adhesive treated product), and rubber composition (unvulcanized rubber sheet), use the following method to A toothed belt was produced.
- First, the fiber fabric forming the tooth cloth is wound around the outer peripheral surface of a cylindrical mold having a plurality of grooves (grooves) corresponding to the teeth of the toothed belt. Subsequently, on the outer peripheral surface of the wound fiber fabric, twisted cords constituting the core wire having the composition and configuration shown in Table 3 were helically laid at a predetermined pitch (with a predetermined pitch in the axial direction of the cylindrical mold). to). Further, the unvulcanized rubber sheet forming the back portion and tooth portions is wound around the outer peripheral side to form an unvulcanized belt molded body (unvulcanized laminate).
- Next, the unvulcanized belt molded body is placed on the outer periphery of the cylindrical mold, and the outside thereof is covered with a rubber jacket as a vapor barrier material. Subsequently, the jacketed belt compact and the cylindrical mold are placed inside a vulcanizing apparatus such as a vulcanizing can. Then, when the belt molded body is heated and pressurized inside the vulcanizing device, the rubber composition of the unvulcanized rubber sheet and the fiber fabric are press-fitted into the grooves (concave grooves) of the cylindrical mold, and the teeth of the desired shape are formed. is formed, and the rubber composition of the unvulcanized rubber sheet is vulcanized to form a sleeve-shaped vulcanized molded body (vulcanized belt sleeve) in which the rubber composition, the fiber fabric, and the cord are integrated. be done. At this time, the fiber fabric is stretched along the contour shape of the tooth portion to form a tooth cloth arranged on the surface of the tooth portion. Then, the vulcanized belt sleeve removed from the cylindrical mold is cut into predetermined widths to obtain a plurality of toothed belts with predetermined names.

(pulley layout)
- The belt systems of Example 1 (Fig. 13), Example 2 (Figs. 14 and 15), Example 3 (Fig. 16), and Comparative Examples 1 and 2 (Fig. Equipped with a 2-shaft layout with a fixed shaft without an imparting mechanism (shifting the shaft distance, tension pulley, tensioner, etc.), and equipped with a shaft load detector (load cell) that can be connected to the rotating shaft of one (driving pulley). I assumed.
・Number of teeth of drive pulley/pulley diameter (assuming core line): 30 teeth/76.394 mm
・Number of teeth of driven pulley/pulley diameter (assuming cord line): 30 teeth/76.394 mm
The toothed pulleys of Examples 1-3 (FIGS. 2, 17, and 18) and Comparative Examples 1-2 (FIG. 19) were both used as drive pulleys in the above layout. There is no difference in the effect obtained whether the applied pulley is a driving pulley or a driven pulley, and it is considered that this problem can be solved.

(Example 1: Fig. 13)
・Required tension when the belt is attached: The level is about 300N.
- Number of relevant toothed pulleys with split pulleys: 1 (applied to drive pulley)
・When viewed in the direction of the central axis of the rotating shaft, the central angle α of the arc portion connecting the outer edges of the grooves in some of the split pulleys is 180°, and the winding angle of the toothed belt with respect to the toothed pulley (180° ) was set the same as
・Perimeter of pulley layout before belt installation (L1): 796.39 mm
(Peripheral length of the pulley layout in a state in which the arc portion stays in the inner region of the circumference of the pulley layout including the toothed pulley when viewed in the rotation axis direction of the rotation shaft)
・Pulley layout circumference after belt installation (L2): 840.00 mm

(Embodiment 2: FIGS. 14 and 15)
・Required tension when the belt is attached: The level is about 300N.
- Number of relevant toothed pulleys with split pulleys: 1 (applied to drive pulley)
・When viewed in the direction of the central axis of the rotating shaft, the central angle α of the arc portion connecting the outer edges of the grooves in some of the split pulleys is 84°, and the winding angle of the toothed belt with respect to the toothed pulley (180° ) was set smaller than
・Perimeter of pulley layout before belt installation (L1): 740.21 mm
・Pulley layout circumference after belt installation (L2): 840.00 mm

(Example 3: FIG. 16)
・Required tension when the belt is attached: The level is about 300N.
- Number of relevant toothed pulleys with split pulleys: 1 (applied to drive pulley)
・When viewed in the direction of the central axis of the rotating shaft, the central angle α of the arc portion connecting the outer edges of the grooves in some of the split pulleys is 276°, and the winding angle of the toothed belt with respect to the toothed pulley (180° ).
・Perimeter of pulley layout before belt installation (L1): 835.12 mm
・Pulley layout circumference after belt installation (L2): 840.00 mm

(Operation: Examples 1 to 3)
(1) In a pulley layout in which the toothed pulley of the above embodiment is used as a drive pulley, the pulley layout circumference length (L2) after the belt is attached according to the required tension level (about 300 N) when the belt is attached. (Belt circumferential length after tension is applied at the time of installation through a predetermined step) becomes 840.00 mm, which is 0.63 mm (0.075%) longer than the belt reference circumferential length (L0: 839.37 mm). , the two pulleys (two shafts) were fixed (distance between shafts: 300.00 mm).

(2) Preparatory step (FIG. 9 for Example 1, FIG. 14(A) for Example 2, and FIG. 16(A) for Example 3)
One (part) of the split pulleys configured to be connectable to the rotating shaft and the other (remaining) split pulley are not attached to the outer periphery of the boss, and the toothed belt is placed between the pulleys. As a belt mounting pulley used when mounting, it is connected to the rotating shaft of the driving pulley via a fixing means (base member), and one (part) of the split pulleys when viewed in the central axis direction of the rotating shaft The arc portion connecting the outer edges of the grooves in the pulley layout including the toothed pulley (a line formed annularly along the outer circumference of each pulley so as to connect the outer circumference of each pulley) stays in the inner area A pulley layout is provided in the mode.
As a result, the circumference (L1) of the pulley layout before the belt is attached is 796.39 (mm) in Example 1 and 740.21 (mm) in Example 2 with respect to the belt reference circumference (L0: 839.37 mm). (mm), and Example 3 is shortened to 835.12 (mm).

(3) Suspension step (Fig. 10 for Example 1, not shown for Examples 2 and 3)
Therefore, a toothed belt having a relatively high level (285 KN) of belt elastic modulus could be easily suspended on the pulley layout.

(4) Tension applying step (FIGS. 11 and 12 for Example 1, FIGS. 14 (B) and 15 (D) for Example 2, and not shown for Example 3)
(Examples 1 and 3)
Using the principle of leverage (connecting a hexagonal wrench to the end of the rotating shaft of the part of the split pulley), the pulley for belt attachment (the outer circumference of the boss part is composed only of the part of the split pulley). When viewed in the central axis direction of the rotation shaft, the belt mounting pulley is rotated to a position where the circular arc portion substantially overlaps the pulley layout circumference, and the belt reference circumference length (L0: 839. 37 mm), the pulley layout circumference (L2) after the belt is attached is 840.00 mm, which is 0.63 mm (0.075%) longer, and the belt is placed between the pulleys while applying tension to the suspended toothed belt. I put it on.

(Example 2)
As detailed below, the tensioning step and the assembly step described later were divided into two stages and repeated.
In other words, first, using the principle of leverage (connecting a hexagon wrench to the end of the rotating shaft of the part of the split pulley), the pulley for belt attachment [the outer peripheral part of the boss part is part of the split pulley ( The pulley composed only of the central angle α of the circular arc portion: 84°) is rotated by approximately 132°, that is, when viewed in the central axis direction of the rotation shaft, the circular arc portion substantially overlaps the pulley layout circumference, and the assembly In the step, the belt mounting pulley is rotated to a position where the toothed belt does not need to be pushed outward in the radial direction of the toothed pulley against the tension of the toothed belt, and the suspended toothed belt is 1 A staged tension was applied (see FIG. 14(B)).
In this state, a part of the assembly step described later [Connect the first of the remaining split pulleys (divided into two) to the rotation shaft of the belt mounting pulley (the one with the central angle α of the arc part of 96°) operation] was performed (see FIG. 14(C)).
Furthermore, using the principle of leverage, the belt mounting pulley is rotated by approximately 96°, that is, in the assembling step, the toothed belt is spread outward in the radial direction of the toothed pulley against the tension of the toothed belt. Rotate the belt mounting pulley to a position where it can be omitted, and finally set the pulley layout circumference (L2) after belt mounting to 0.63 mm with respect to the belt reference circumference (L0: 839.37 mm). (0.075%) long 840.00 mm, the belt was mounted between the pulleys while applying final mounting tension to the suspended toothed belt (see Figure 15(D)).
In this state, the remaining work in the assembling step [the work of connecting the remaining one split pulley (the center angle α of the arc portion is 180°) to the rotation shaft of the belt mounting pulley] was performed (Fig. 15(E)).

(5) Assembly step (Figs. 13, 14(C), 15(E), 16(B))
Finally, by connecting the other (remaining) split pulley to the rotation shaft of the belt mounting pulley via a fixing means, one (part) split pulley and the other (remaining) split pulley are circularly connected. The toothed pulley is formed integrally in an annular shape and has exactly the same external shape and function as a normal toothed pulley.

(Comparative Examples 1 and 2: FIG. 20)
(Comparative Example 1: FIG. 20(A))
・Pulley layout circumference (L): 839.37 mm (fixed)
(Comparative Example 2: FIG. 20(B))
・Pulley layout circumference (L): 840.00 mm (fixed)

(Operation: Comparative Examples 1 and 2)
(Comparative example 1)
(1) In the pulley layout in which the toothed pulley of Comparative Example 1 was previously used as the drive pulley, the pulley layout circumference (L) (fixed) was the same length as the belt reference circumference (L0: 839.37 mm). The distance between the two pulleys (two shafts) was fixed so that the distance between the two pulleys was 299.69 mm.

(2) With respect to the pulley layout (pulley layout in which the circumference of the pulley layout is the same as the belt reference circumference), the toothed belt was suspended by human hands (without tools) and mounted between the pulleys.

(Comparative example 2)
(1) In the pulley layout in which the toothed pulley of Comparative Example 2 was previously used as the drive pulley, the pulley layout circumference (L) (fixed) was slightly longer than the belt reference circumference (L0: 839.37 mm). The distance between the two pulleys (2 shafts) was fixed (distance between shafts: 300.00 mm) so that the length (840.00 mm) was obtained.

(2) With respect to the pulley layout (pulley layout in which the circumference of the pulley layout is slightly longer than the reference belt circumference), the toothed belt was suspended by human hands (without jigs and tools) and mounted between the pulleys.

[Evaluation of toothed pulleys: items, methods, criteria]
For each test piece (Examples 1 to 3, Comparative Examples 1 and 2), in order to determine whether a toothed pulley capable of solving the problem of the present application was obtained, the wearability of the belt and the tension when the belt was worn were verified. .

[Wearability of the belt]
(Method, Criteria)
If a toothed belt with a relatively high elastic modulus (for example, about 200 to 400 KN) can be suspended on a pulley layout by human hands (with a force of about 100 N, without jigs and tools) and can be installed between the pulleys. , the wearability of the belt was evaluated as good (no problem in practical use), and was evaluated as a.
A toothed belt with a relatively high elastic modulus (for example, about 200 to 400 KN) could not be suspended on a pulley layout by human hands (about 100 N force, without jigs and tools), and could not be installed between pulleys. In this case, the wearability of the belt was evaluated as unsatisfactory, and was judged as b.
From the viewpoint of suitability for actual use in this application (wearability of the belt), toothed pulleys rated a were taken as acceptable levels.

[Tension when belt is attached]
(Method)
The belt tension was calculated from the shaft load detected by a shaft load detector (load cell) connected to one (driving pulley) rotating shaft.

(criterion)
A judgment was made when the tension (initial tension) at the time of wearing a toothed belt with a relatively high level of belt elasticity (for example, about 200 to 400 KN) could be set to a relatively high level (for example, about 200 to 400 N). .
If the tension (initial tension) of a toothed belt with a relatively high elastic modulus (for example, about 200 to 400 KN) cannot be set to a relatively high level (for example, about 200 to 400 N), the b judgment is made. did.
From the viewpoint of suitability for actual use in this application (tension when belt is attached), toothed pulleys rated a were taken as acceptable levels.

[Comprehensive judgment]
The criteria for comprehensive judgment (ranking) of toothed pulleys that can solve this problem are as follows, based on the judgment results of the above two test items (belt mountability, tension when belt is mounted). .
Rank A: In the above evaluations (wearability of the belt, tension when the belt is worn), when both were evaluated as a, it was judged as a sufficiently satisfactory rank (acceptance) as a solution to this problem.
Rank B: In the above evaluation (wearability of the belt, tension when the belt is worn), even if there was a judgment of b, it was regarded as an insufficient rank (failure) as a solution to this problem.

[inspection result]
Table 5 shows the verification results.

(obtained effect)
・From the above verification results, when the toothed pulleys of Examples 1 to 3 are applied to a pulley layout that does not have a conventional tension applying mechanism (axis distance movement, tension pulley, tensioner, etc.), before belt installation The circumference of the pulley layout (L1: 796.39 mm in Example 1, 742.83 mm in Example 2, and 834.02 mm in Example 3) is made shorter than the reference belt circumference (L0: 839.37 mm) Therefore, a toothed belt having a relatively high elastic modulus (285 KN in the example) can be easily suspended on the pulley layout, and the pulley layout after the belt is attached can be easily suspended. The circumference of the belt (L2: 840.00 mm) can be easily made longer than the belt reference circumference (L0: 839.37 mm). It was found that the belt can be mounted between the pulleys while raising the level (312 N in Examples 1 to 3) significantly higher than the conventional level (98 N in Comparative Example 1) in which almost no tension was applied during mounting. As a result, it can be seen that it can be used for applications with higher loads.

1 toothed pulley 11 base member 111 boss portion 112 flange 12 first split pulley 13 second split pulley 14 groove portion 2 toothed belt 100 synchronous transmission belt system

Claims (12)

A toothed pulley having grooves formed on its outer circumference that meshes with the teeth of a toothed belt,
a boss connectable to the rotating shaft;
a plurality of divided pulleys attached to the outer peripheral side of the boss portion and having a shape divided into a plurality of portions in the circumferential direction of the boss portion;
fixing means for fixing the positional relationship of the plurality of split pulleys in the direction of the rotation axis;
with
Of the plurality of split pulleys, some of the split pulleys can be attached to or integrated with the outer periphery of the boss while the remaining split pulleys are not attached to the outer periphery of the boss. There is a toothed pulley. The toothed pulley according to claim 1, wherein the number of said plurality of split pulleys is two. 2. The toothed pulley according to claim 1, wherein said groove has a shape extending in said rotating shaft direction. The fixing means has a configuration in which the boss portion and a flange portion extending radially outward from one side of the boss portion are integrally formed,
2. The toothed pulley according to claim 1, further comprising a fastening member that fastens said plurality of split pulleys and said flange portion. 5. The toothed pulley of claim 4, wherein said flange portion extends from one side of said boss portion to at least an outer edge of said groove portion. 2. The tooth according to claim 1, wherein the split pulley and the fixing means have a structure in which a concave recess formed on one side and a convex protrusion formed on the other side are concentrically fitted. pulley. 7. The split pulley according to claim 6, wherein said split pulley has said convex portion on one side, said fixing means has said concave portion on one side, and said convex portion and said concave portion are concentrically fitted together. toothed pulley. The toothed pulley according to claim 1, wherein the plurality of split pulleys are split in the circumferential direction at the bottom surface of the groove. A toothed belt having a plurality of teeth arranged at predetermined intervals along the longitudinal direction of the belt, and a pulley layout consisting of two or more toothed pulleys spaced apart from each other and to which the toothed belt is to be attached; A synchronous transmission belt system comprising:
At least one of the two or more toothed pulleys is the toothed pulley according to any one of claims 1 to 8,
The part of the split pulleys can be attached to the outer periphery of the boss or integrated with the outer periphery of the boss while the remaining split pulleys are not attached to the outer periphery of the boss. Functioning as a belt mounting pulley used when mounting to the pulley layout,
Before the toothed belt is attached to the pulley layout, when viewed in the direction of the rotation axis, an arc portion that connects the outer edges of the grooves formed on the outer circumference of the partial split pulley is formed by connecting the toothed pulley. a synchronous transmission belt system configured to be arranged to rest on an inner region of the circumference of said pulley layout comprising: Synchronous transmission belt system according to claim 9, wherein only one of said two or more toothed pulleys is the toothed pulley according to any one of claims 1-8. A central angle of the arc portion viewed in the rotation axis direction is equal to or greater than a winding angle of the toothed belt around the toothed pulley, and a central angle of the arc portion viewed in the rotation axis direction is , the circumference of the pulley layout is less than the belt reference circumference of the toothed belt in a state in which the arc portion stays in the inner region of the circumference of the pulley layout including the toothed pulley. 10. The synchronous transmission belt system of claim 9, within the range. 10. A method of mounting the toothed belt to the pulley layout in the synchronous transmission belt system of claim 9, comprising:
The boss portion is connected to the rotating shaft, and attached to the outer peripheral side of the boss portion, or integrated with the outer peripheral side of the boss portion. A preparation step of providing the pulley layout in such a manner that the arc portion connecting the outer edges of the grooves formed on the outer circumference of some of the split pulleys stays in the inner region of the circumference of the pulley layout including the toothed pulley;
a suspension step of suspending the toothed belt on the pulley layout provided in the preparation step;
a tension applying step of rotating the toothed pulley including the partial split pulley and applying tension to the toothed belt when it is worn;
and an assembly step of attaching the remaining split pulley to the outer peripheral side of the boss portion via the fixing means.

Images