JPS6324183B2 - - Google Patents

Description

[Detailed Description of the Invention] Rubber V-belts have conventionally been used as driving endless belts that are used with pulleys, particularly pulleys of continuously variable transmissions, to transmit torque between a pair of pulleys. When durability and high torque transmission performance are required, an endless belt is being used in which a large number of plate-shaped metal blocks having a cross-sectional shape that crosses the V-belt are bound together with a metal band.

In this type of endless belt, the front shape of the metal block is the cross-sectional shape of the V-belt, that is, the width of the belt from the outer circumferential side to the inner circumferential side of the belt, which is to be in contact with the conical contact surface of the pulley, is on both side edges. It is a plate-shaped block with a trapezoidal shape with an inclined contact surface that reduces the width, and a thickness of about 1/4 to 1/10 of its maximum width. Recesses are formed from both side edges of the metal block so as to form a metal band support surface at a position on the outer side of approximately 1/2 of the distance to the edge, and the metal belts are respectively engaged in the recesses. A large number of the metal blocks are arranged in parallel in the thickness direction of the metal blocks and bound together,
It is known that the front and back surfaces of each metal block are tapered at a portion on the inner peripheral side of the metal band support surface, so that the metal block is allowed to curve in an arc shape around the rotation axis of the pulley. 1977-
(Refer to Publication No. 52253).

This type of belt has little wear and aging even after long-term use, and is suitable for high-torque transmission.Especially, each pulley has a pair of conical flanges that are always pushed close to each other by the elasticity of the spring. Also, one of the pair of pulleys is adapted to change the spacing between the conical flanges by the action of centrifugal force, and is particularly suitable for use in a continuously variable transmission in which a V-belt is stretched between both pulleys. However, since it simply consists of a large number of metal blocks arranged in parallel and a metal band engaged in the recess, the metal blocks may fall off from the metal band when passing them around a pulley after stitching. Due to the accuracy of the block and band and the unevenness of the frictional force between the inclined contact surfaces on the left and right end faces of the block and the frictional contact surface of the pulley, etc., the gap between the metal block and metal band is Skidding occurs, causing uneven wear and fatigue of the metal block and metal band, impairing efficiency, and in the worst case, there is a risk that the metal block may fall off from the metal band during operation.

The present invention attempts to eliminate the above defects by maintaining the relative position of the metal block and metal band normally during assembly and operation, and the metal block has a front shape that is similar to the contact surface of the pulley. The slits for receiving the metal band are formed in a trapezoidal shape on a part or all of the end faces on both sides, and the slits are formed in a straight line whose extension lines intersect the slanted contact faces on the both end faces at approximately equal angles. The slit is formed so as to open only on one side end face of the block, and a step portion cut out a little distance from the open end is formed on one side edge of the slit facing the metal band. The thickness of the metal band is equal to or smaller than the width of the linear slit, and the width is set between the inner end of the slit and the contact surface of the pulley on the extension line of the slit. The metal band is formed into an endless shape, and a large number of the blocks are arranged in parallel in the thickness direction of the metal band.
These metal blocks are inserted into the slit and connected together.

The drawing shows one embodiment of the present invention, and the metal block 1 has a trapezoidal front profile as shown in FIG. The inclined contact surface 3 is in contact with the frictional contact surfaces 2, 2 forming an endless belt, and when an endless belt is constructed, the surface that forms the inner peripheral surface is formed into a linear surface 4, and the linear surface 4 is formed in the diametrical direction of the pulley. At a position approximately 1/2 or slightly above the height of the metal block 1 from 4, a support surface 5 is provided with the wall surface of the inner circumferential surface, and its extension lines intersect with the inclined contact surfaces of both end surfaces at approximately the same angle. Slit 6
is bored so as to open only on one side edge (the left side edge in FIG. 1), and the upper half 7 on the outer peripheral side of the support surface 5 has a uniform thickness. Face 5
As clearly shown in the side view of FIG. 2, the lower half 8 on the inner circumferential side is made of a plate-like material with one surface (the upper surface in FIG. 1) formed into a tapered surface 9.
In order to give the side edge 21 of the metal band 20 a degree of freedom, the open end of the slit 6 is shortened by cutting out the free end 10 of the upper half 7, and the open end of the slit 6 is shortened by cutting out the free end 10 of the slit 6 in order to give the side edge 21 of the metal band 20 a degree of freedom. A stepped portion 11 is formed by cutting out a certain distance from the end. Further, a truncated conical protrusion 12 is formed protrudingly on one surface (the front surface in FIG. 1) of the metal block 1 at a suitable location of the upper half 7, and a corresponding projection 12 is formed on the other surface (the back surface in FIG. 1) of the metal block 1. A recess 13 into which the protrusion 12 is received and fitted is formed at the position.

The metal band 20 is an endless band formed by stacking, for example, 10 endless metal bands, and its thickness is equal to the width of the slit 6 of the metal block 1 (the supporting surface 5 in FIG. 1 and the corresponding outer periphery). The width of the slit is equal to or smaller than the distance between the slit and the side wall surface, and the width is equal to or smaller than the distance between the rear end 14 of the slit and the frictional contact surface 2 of the pulley located on the extension line of the slit 6. The distance is approximately equal to (including a slightly larger dimension) or slightly smaller than the distance.

An endless belt is constructed by arranging a large number of such metal blocks 1 in parallel in the thickness direction and inserting the metal band 20 through the slits 6, and the endless belt is connected between the friction contact surfaces 2 of the pulleys. When put together, the inclined contact surfaces 3, 3 formed on both side edges of each metal block 1 come into contact with the conical friction contact surface 2 of the pulley, and the side edges of the metal band 20 protruding from the slit 6. 2
1 directly contacts or faces the friction contact surface 2 at a slight distance on the extension line of the slit 6, so that after the endless belt is assembled to the pulley, there is no space between the metal block 1 and the metal band 20. Even if a deviation occurs in the width direction of the metal band 20, the relative relationship is corrected and the deviation is eliminated each time the metal block 1 comes into contact with the pulley, so that the metal block 1 does not come off the metal band 20 during torque transmission drive. The fear of falling off is eliminated. Further, a stepped portion 1 is cut out at a distance slightly from the opening end of the slit 6 on the support surface 5 forming one side edge of the slit 6.
1, the side edge 21 located at the open end of the slit 6 of the metal band 20 has a degree of freedom from bending stress and other forces applied to the metal band 20 when the relative position is corrected. give.
Further, due to the formation of the stepped portion 11, the supporting surface 5, which is the side edge of the slit 6 on the lower half 8 side of the metal block 1, faces the metal band 20 approximately at the center in the width direction of the metal block 1. , when the metal block 1 is brought into contact with the frictional contact surface 2 of the pulley by its inclined contact surface 3 and a centrifugal force directed outward in the radial direction of the pulley is applied, the support surface 5 is strongly frictionally applied to the metal band 20. However, since the support surface 5, which is the contact engagement surface between the metal block 1 and the metal band 20, is limited to approximately the center of the metal block 1 in the width direction, the metal block 1 and the metal band 20 are engaged with each other. Even if there is an inclination between the band 20 and the band 20,
There is almost no displacement of the metal band 20 in the width direction.

Note that the truncated conical projection 1 is provided on the metal block 1.
2 and a recess 13 into which the protrusion 12 is received and fitted, these protrusions 12
The fitting engagement between the metal block 1 and the recess 13 prevents the metal block 1 from shifting while it is being bridged between the pulleys, and the metal block 1 is regulated and aligned.
The metal block 1 curves the endless belt into an arc by means of a tapered surface 9 formed on its lower half 8, and brings the contact surfaces 3, 3 of both end surfaces into contact with the friction contact surfaces 2, 2 of the pulleys. Drive travels in an arc centered around the rotation center axis. At this time, since the tapered surface 9 is formed on the lower half 8 of the metal block 1 with the metal band support surface 5 as a boundary, the metal band 20 is curved along the support surface 5, and the inclined contact surface 3 is connected to the pulley. Frictional contact surface 2,2
to ensure contact with the pulley.

In the present invention, the endless driving belt has inclined contact surfaces that come into contact with the contact surfaces of the pulleys formed on part or all of the both side edges, and a linear slit through which the metal band is inserted is formed on one side edge. A metal block is formed with an opening formed only in the slit, and a step portion is formed on the side edge of the lower half of the slit, which constitutes the support surface of the metal band, by cutting out a distance from the opening end, and the thickness is reduced. The width is equal to or smaller than the width of the slit, and the width is approximately equal to or slightly smaller than the distance between the inner end of the slit and the contact surface of the pulley located on the extension line of the slit. A large number of metal blocks are arranged in parallel in the thickness direction of the metal blocks, and the metal bands are inserted into linear slits in the metal blocks to connect the metal blocks in a continuous manner. Therefore, an endless belt can be constructed simply by engaging a metal block from one end of a metal band through its slit, and when passing the endless belt between a pair of pulleys, The block's inclined contact surface abuts against the conical friction contact surface of the pulley, and the side edge of the metal band protruding from the slit directly contacts the friction contact surface of the pulley, which is an extension of the slit. Since they are in a position where they are in contact or facing each other with a slight distance between them, the relative position between the metal block and the metal band is corrected each time the metal block comes into contact with the pulley during torque transmission drive between the pair of pulleys. Even if the metal block is misaligned in the width direction of the metal band, the misalignment is always corrected, so there is no risk of the metal block coming off the metal band during torque transmission driving.
Further, by forming a step portion cut out a little distance from the opening end on the side edge of the lower half of the slit that constitutes the support surface of the metal band, the step part is located at the opening end of the slit of the metal band. The side edge is given freedom from bending stress and other forces applied to the metal band when the relative position is corrected, and furthermore, by forming the step, the side edge of the lower half of the metal block of the slit is Since a certain support surface faces the metal band near the center in the width direction of the metal block, the metal block comes into contact with the frictional contact surface of the pulley by its inclined contact surface, and the centrifugal force directed outward in the radial direction of the pulley is generated. When the supporting surface is strongly frictionally engaged with the metal band due to Therefore, even if there is an inclination between the metal block and the metal band, there will be almost no deviation in the width direction of the metal band.

According to the present invention, each pulley is always urged to approach the pair of conical flanges by the elasticity of the spring, and the distance between the conical flanges is reduced by the action of centrifugal force on one of the pair of pulleys. When used in a continuously variable transmission with an endless belt running between both pulleys,
Even if the diametrical position of the conical flange changes, the relationship between one side edge of the metal band and the contact surface of the conical flange on the extension of the linear slit remains the same, preventing the metal block from falling off. It maintains the effect of

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a front view of a metal block, Fig. 2 is a side view of a part of an endless belt in which metal blocks are connected, and Fig. 3 is an exploded slope view thereof. It is. In the figure, 1 is the metal block, 3 is its inclined contact surface, 4 is its linear surface, 5 is its metal band support surface, 6 is its slit, 7 is its upper half, 8 is its lower half, Reference numeral 9 indicates the tapered portion thereof, 20 indicates the metal band, 21 indicates one side edge thereof, and 2 indicates the friction contact surface of the pulley.

Claims (1)

[Claims] 1. For transmitting torque between a pair of pulleys having contact surfaces formed by opposing two conical surfaces, a part or all of both side surfaces are in contact with the contact surfaces of the pulleys. An endless driving belt comprising a plurality of trapezoidal metal blocks each having an inclined contact surface and bound together by a metal band, the belt having a trapezoidal frontal shape with inclined contact surfaces contacting the contact surfaces of the pulleys formed on both end faces. , and a linear slit that intersects the inclined contact surfaces of the both end faces at equal angles is formed so as to open only on the one side end face, and a lower half of the slit constitutes a support surface for the metal band. A large number of metal blocks having a predetermined thickness are formed in the side edge of the block with a step cut out by a distance from the opening end, and a large number of metal blocks are arranged in parallel in the thickness direction of the blocks, and an endless metal band is inserted through the slit. These metal blocks are connected together, and the metal band has a thickness that is equal to or smaller than the width of the slit in the metal block, and a thickness that is equal to or smaller than the width of the slit in the metal block, and a distance between the inner end of the slit and the pulley located on the extension line of the slit. 1. An endless belt for driving, characterized in that it is constructed in the shape of a flat belt and has a width that is approximately equal to or slightly smaller than the distance between the belt and the contact surface of the belt. 2. Each of the metal blocks has a protrusion formed at a fixed position on one surface of its upper half, and a recess into which the protrusion is received and fitted is formed on the other surface. The endless driving belt according to item 1.