JPH078921Y2 - Flat belt transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of a flat belt transmission device using a flat belt.

(Prior Art) Conventionally, in a flat belt transmission device that transmits a load by a flat belt, in order to prevent the belt from meandering or being offset on the flat pulley, a crown portion is provided on the outer circumference of the pulley. It is generally well known to provide (middle and high section) (for example, Japanese Utility Model Publication Nos. 50-121147 and 58-189844,
(See various publications such as Japanese Utility Model No. 62-2514).

Further, when such belt meandering or deviation is extremely disliked, the width wp of the pulley a is made wider than the width W of the belt b, as shown in FIG. ~ 3m
Along with giving a space of about m, flanges c having a thickness of about 1 mm are attached to both ends of the pulley a.

(Problems to be solved by the invention) However, in this conventional device, the pulley width wp becomes wider by adding the clearance width on both sides of the belt b and the thickness of both flanges c, c to the belt width W. Especially, when the transmission load is light, the tendency becomes strong. Therefore, it is disadvantageous in that the belt transmission is made compact and lightweight.

The present invention has been made in view of the above problems, and an object thereof is to change the position of a flange that restricts the movement of a flat belt in the belt width direction so that the belt moves in the width direction on a pulley. While preventing this, the width of the pulley is narrowed to approximately the same as the width of the belt, and the flat belt transmission is made compact and lightweight.

(Means for Solving the Problem) In order to achieve the above object, the solution means of the present invention is basically such that the position of the flange that restricts the movement of the flat belt in the belt width direction is located at the intermediate portion in the width direction of the pulley. Arrange.

Specifically, in the invention according to claim (1), in a flat belt in which a plurality of endless core bodies are embedded in a belt base body in parallel to each other, in a width direction intermediate portion of an inner peripheral surface of the belt base body. , A groove extending in the belt length direction and deeper than the position of the core body is formed. On the other hand, with respect to the flat pulley, a flange that fits in the groove of the flat belt is provided in the widthwise intermediate portion of the outer circumference.

Further, in the invention according to claim (2), at least two or more crown portions are provided on the outer periphery of the flat pulley side by side in the width direction corresponding to the portions other than the concave grooves of the flat belt, and between the crown portions. Provide a flange that fits in the groove of the flat belt.

Further, in the invention according to claim (3), one crown portion is provided on the outer periphery of the flat pulley, and a flange that fits in the groove of the flat belt is provided at the widthwise intermediate portion of the crown portion.

(Operation) With the above structure, in the invention according to claim (1), (2) or (3), a concave groove deeper than the position of the core body is formed on the inner circumference of the flat belt, and the outer circumference of the flat pulley is formed. Since a flange that can fit in the groove on the inner circumference of the flat belt is formed in the middle portion in the width direction, when the belt transmission is in operation, the belt on the outer circumference of the pulley has the groove on the outer circumference of the pulley. Since the vehicle travels in a state of being engaged with the flange and its movement in the width direction is restricted, it is possible to reliably prevent the meandering and the deviation. At that time, since the depth of the concave groove of the flat belt is deeper than the position of the core body, the flat belt is almost divided into a plurality of flat belt portions with the position of the concave groove as a boundary. Even if a biasing force is generated in the belt by the tension in the engagement state with the flange, the shearing force acting between the side wall of the groove and the flange of the belt base is suppressed, and the wear of the side wall of the groove is reduced. can do.

In addition, since the movement of the belt is restricted by the flange in the widthwise middle portion of the pulley, the width and the thickness of the flange on both sides of the pulley in the width direction are not required at all, which makes the width of the pulley equal to the belt width. It is possible to make it as narrow as possible, so that the belt transmission can be made compact and lightweight.

In particular, in the invention according to claim (2) or (3), since the crown portion is formed on the outer circumference of the pulley, movement of the belt in the width direction can be reliably prevented not only by the flange but also by the crown portion. it can.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 schematically shows the overall structure of a flat belt transmission A according to an embodiment of the present invention, in which 1 is a drive shaft and 2 is a driven shaft arranged in parallel with the drive shaft 1. The drive shaft 1
A drive pulley 3 is mounted on the driven shaft 2, and a driven pulley 4 is mounted on the driven shaft 2 so as to rotate together, and a flat belt 5 is wound between the pulleys 3 and 4.

As shown in the enlarged detail of FIG. 1, the flat belt 5 includes a belt base 5a made of hard rubber, and a plurality of endless core bodies arranged in parallel with each other and embedded in the belt base 5a.
, 5b, 5b, ..., On the inner peripheral surface of the belt base 5a that contacts the pulley 1, two bottomed recessed grooves 6 extending in the belt length direction are formed at three equal positions in the belt width direction. 6 are formed. Each groove 6 extends between the cores 5b, 5b to the belt back side from the position of the core 5b, and its cross section is substantially rectangular.

On the other hand, the drive and driven pulleys 3 and 4 are both flat pulleys and have the same structure. For example, the drive pulley 3 will be described. As shown in FIG.
The outer peripheral surface of the drive pulley 3 is located on a cylindrical surface at the same distance from the pulley center, and the outer peripheral surface has three crown portions 7, 7,
Are formed side by side in the width direction corresponding to the portions other than the concave grooves 6, 6 of the flat belt 5, respectively, and these crown portions 7,
7, ... are set to have the same width, crown height and crown radius. Further, between the crown portions 7, 7, ..., Two flanges 8, 8 which are fitted into the concave grooves 6, 6 of the flat belt 5 are provided.
Are formed at intervals in the pulley width direction, the protruding height dimension of each flange 8 from the pulley outer peripheral surface is smaller than the depth dimension of the concave groove 6 of the belt 5, and the tip of the flange 8 has the concave groove 6 It does not touch the bottom.

Therefore, in the above-described embodiment, the two recessed grooves 6, 6 are formed on the inner circumference of the flat belt 5, and on the other hand, on the outer circumference of the drive and driven pulleys 3, 4 made of flat pulleys, in the middle portion in the width direction. Has two flanges 8 and 8 which can be fitted into the concave grooves 6 and 6 on the inner circumference of the flat belt 5, respectively. Therefore, when the belt transmission A is in operation, the outer circumference of the pulley 3 (or 4) is The riding belt 5 travels in a state in which the concave grooves 6, 6 are engaged with the flanges 8, 8 on the outer circumference of the pulley 3 (or 4), respectively. By the engagement of the concave grooves 6 and 6 with the flanges 8 and 8, the movement of the belt 5 on the pulley 3 (or 4) in the width direction is regulated, and the meandering and the deviation of the belt 5 are surely generated. Can be suppressed.

Moreover, since three crown portions 7, 7, ... Are formed on the outer circumference of the pulley 3 (or 4), each crown portion 7 is formed.
Also, the movement of the belt 5 in the width direction is suppressed, and thus the meandering and deviation of the belt 5 can be suppressed more reliably.

At that time, since the depth of each concave groove 6 of the belt 5 is deeper than the position of the core body 5b, the flat belt 5 is almost divided into a plurality of flat belt portions with the position of the concave groove 6 as a boundary. When the belt 5 is engaged with the flange 8 of the pulley 3 (or 4) and a biasing force is generated in the belt 5 between the rubber portion of the side wall of the groove 6 of the belt base 5a and the flange 8. The shearing force acting is suppressed, wear of the rubber portion can be reduced, and the life of the belt 5 can be extended.

Thus, the movement of the belt 5 in the width direction is caused by the pulley 3
(Or 4) As a result of being restricted by the flanges 8,8 and the crown portions 7,7, ... in the widthwise middle part, the clearance dimension and the thickness of the flange on both sides of the belt when the flanges are attached to both ends of the pulley in the width direction Is not necessary at all, which allows the width wp of the pulley 3 (or 4) to be narrowed to substantially the same width as the belt width W, thus making the belt transmission A compact and lightweight.

It should be noted that the present invention is not limited to the above-mentioned embodiment, but includes various modified embodiments. For example, in the above embodiment,
Two concave grooves 6, 6 are formed on the inner circumference of the belt 5, and the pulley 3
Although three crown portions 7, 7, ... And two flanges 8,8 are provided on the (or 4) side, the number of these can be increased or decreased. In the embodiment shown in FIG. 3, the number of the concave grooves 6 on the inner circumference of the belt 5 is reduced to one, and the number of grooves on the pulley 3 (or 4) side is 2
One crown portion 7, 7 ... And one flange 8 are provided.

Further, in the above embodiment, a plurality of crown portions 7, 7, ... Are formed on the outer periphery of the pulley 3 (or 4), but as shown in FIGS. One crown portion 7 may be provided on the outer circumference, and one or two or more flanges 8 that fit into the groove 6 of the flat belt 5 may be formed in the widthwise intermediate portion of the crown portion 7. The same operational effect as can be obtained.

Further, as shown in FIGS. 6 and 7, the outer circumference of the pulley 3 (or 4) may be a flat cylindrical surface without the crown portion 7, and one or more flanges 8 may be formed on the outer peripheral surface thereof. . Further, as shown in FIG. 8, the concave groove 6 of the belt 5 is formed into a generally dovetail shape with a middle expansion, and the sectional shape of the flange 8 of the pulley 3 (or 4) is formed into an inverted trapezoidal shape whose width increases toward the tip. Good.

Finally, a specific example will be described. A belt corresponding to the embodiment shown in FIG. 3 and a driving and driven flat pulley having a diameter of 100 mm were prepared. This flat belt was wrapped around a drive and driven pulley, and the behavior of the belt in the width direction was evaluated by rotating the drive pulley at a rotation speed of 600 to 2600 rpm with an axial load of 50 to 500 kg. I couldn't see any of the belt riding up or biasing of the belt. As is clear from this test evaluation, according to the example of the present invention, without causing the meandering and deviation of the belt,
It can be seen that the flat belt transmission can be made compact and lightweight by making the pulley width substantially the same as the belt width.

(Effect of the Invention) As described above, the claim (1), (2) or (3)
According to the invention described above, the flat belt is provided with a concave groove deeper than the position of the core body on the inner circumference thereof, while the outer periphery of the flat pulley is provided with a flange capable of being fitted to the inner circumference of the belt at an intermediate position in the pulley width direction. By providing the belt, the movement of the belt in the width direction on the pulley can be restricted by the engagement of the belt groove and the flange on the outer circumference of the pulley without shortening the life of the belt. The space provided and the thickness of the flanges on both ends of the pulley can be eliminated, thus preventing the belt from meandering and shifting, while reducing the pulley width to about the same size as the belt width, making the flat belt transmission compact. In addition, it has a practically excellent effect that the weight can be reduced.

Further, in particular, in the device according to claim (2) or (3),
Since the crown portion is formed on the outer circumference of the pulley, the movement of the belt in the width direction can be restricted not only by the flange but also by the crown portion, and thus the belt can be more surely prevented from meandering and deviation.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, and FIG. 1 shows I- of FIG.
FIG. 2 is an enlarged sectional view taken along line I, and FIG. 2 is a front view showing a schematic configuration of a flat pulley transmission device. 3 to 8 are views corresponding to FIG. 1 showing another embodiment of the present invention. FIG. 9 is a view corresponding to FIG. 1 showing a conventional example. A: Flat belt transmission device, 3, 4 ... Pulley, 5 ... Flat belt, 5
a ... Belt base, 5b ... Core, 6 ... Groove, 7 ... Crown, 8 ... Flange.

Claims (3)

[Scope of utility model registration request] 1. A concave groove extending in the belt length direction and deeper than the position of the core body in a widthwise intermediate portion of an inner peripheral surface of a belt base body in which a plurality of endless core bodies are embedded in parallel with each other. And a flat pulley having a flange that fits in the groove of the flat belt in the widthwise intermediate portion of the outer periphery of the flat belt. 2. A concave groove extending in the belt length direction and deeper than the position of the core body in a widthwise intermediate portion of an inner peripheral surface of a belt base body in which a plurality of endless core bodies are embedded in parallel with each other. A flat belt on which is formed at least two crown portions on the outer periphery of the flat belt, which are arranged side by side in the width direction corresponding to portions other than the concave grooves of the flat belt.
And a flat pulley having a flange that fits into the groove of the flat belt between the crown portions. 3. A concave groove extending in the belt length direction and deeper than the position of the core body at a widthwise intermediate portion of an inner peripheral surface of a belt base body in which a plurality of endless core bodies are embedded in parallel with each other. And a flat pulley having a crown portion provided on the outer periphery thereof and having a flange fitted in the groove of the flat belt in the widthwise intermediate portion of the crown portion. And flat belt transmission device.