JP2637452B2 - Transmission belt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a power transmission belt that is used by being stretched between V-groove pulleys.

(Prior Art) Various types of power transmission belts of this type are known in the prior art. For example, Japanese Patent Application Laid-Open Nos.
No. 2,226,730.

The power transmission belt includes an endless link connecting body in which a number of link plates are connected to each other by pins, and a series of V-shaped blocks are sequentially provided in the link connecting body in the longitudinal direction. In practical use, a V-shaped block is wound around a pulley V-groove so that power can be transferred between the V-groove pulleys.

In this type of power transmission belt, when the V-shaped block is wound into or pulled out from the pulley V-groove, the contact position with the pulley V-groove is changed in the pulley longitudinal direction due to the polygonal winding shape caused by the existence of the link plate. Because V
A string vibration is generated in the linear portion of the transmission belt between the groove pulleys, which is repeatedly displaced toward and away from each other. The string vibration not only causes the V-shaped block to collide with the pulley and generates abnormal noise, but also causes vibration due to the fluctuation of the tension of the transmission belt to cause an increase in noise.

In order to solve this problem, it is conceivable to reduce the arrangement pitch of the pins. However, in the conventional transmission belt, the diameter of the pins and the length of the link plate determined in relation thereto are limited to a certain level in terms of strength. The pin pitch cannot be reduced, and there is a limit in reducing the pin arrangement pitch (about 8 mm). Such an arrangement pitch cannot solve the above problem.

Therefore, the applicant of the present application has previously filed Japanese Patent Application No.
A transmission belt with a plurality of endless link joints of the same specifications arranged side by side so that the positions of the pins are shifted, and a V-shaped block sequentially provided to enclose these endless link joints in a horizontal direction has already been proposed. It is. This transmission belt has a pulley V
The shape of the wrap around the groove can be made closer to a circle, which can help solve the above problem.

(Problems to be Solved by the Invention) However, it has been confirmed that even with this countermeasure, the solution of the noise problem is not sufficient.

Therefore, the present invention basically applies the technology described in JP-A-59-226730 to combine two or more types of V-shaped blocks having slightly different widths in the pulley axial direction with respect to the longitudinal direction of the endless link connection body. , So that the noise level at a specific frequency is not particularly increased.

However, in this case, the pulley winding diameter differs between the two or more types of V blocks, causing torque fluctuation.
In particular, immediately before stopping (at a vehicle speed of 5 km / h or less) when the transmission belt is wound around the output pulley of the continuously variable transmission for vehicles at a maximum vehicle speed (vehicle speed of 5 km / h or less), the torque fluctuations due to the difference in the winding diameter of the pulley cause the wheel drive system after the output pulley. It was confirmed that it was amplified by resonance with a large vibration.

(Means for Solving the Problems) In the present invention, the effect of suppressing the noise and the occurrence state of the torque fluctuation greatly contribute to the difference between the maximum value and the minimum value of the pulley axial direction width of the V-shaped block, respectively. Finding things,
The difference above is set so that both are satisfied.
A plurality of endless link connected bodies formed by connecting a large number of link plates to each other by pins are juxtaposed so that the positions of the pins are shifted, and these endless link connected bodies are collectively surrounded in a lateral direction, and a pulley V groove is formed. A plurality of V-shaped blocks having two or more types of pulley axial widths which are frictionally engaged with each other are sequentially provided in the longitudinal direction of the endless link connection body juxtaposed with each other. The difference between the maximum value and the minimum value of the measured width of the V-shaped block in the pulley axial direction is set to 0.08 to 0.13 mm.

(Operation) During practical use of the transmission belt, the V-shaped block located in the pulley V-groove transfers power by frictional engagement with the V-groove pulley, and also transmits power to the endless link connection body. , And predetermined power transmission can be performed.

By the way, two or more types of V-shaped blocks having different pulley axial widths are used as V-shaped blocks, and the difference between the maximum value and the minimum value of the pulley axial direction width of the V-shaped block measured on the pin arrangement pitch line is 0.08 to 0.13. mm, the effect of suppressing noise by using two or more types of V-shaped blocks is sufficiently achieved, and the diameter of the pulley winding of these V-shaped blocks is reduced by using two or more types of V-shaped blocks. The torque fluctuation caused by the difference can be suppressed within an allowable limit.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 to FIG. 3 are a cutaway plan view, a longitudinal sectional side view, and a longitudinal sectional front view of a main part showing an embodiment of the power transmission belt of the present invention.

In these figures, reference numeral 1 denotes a number of rocker joint pins, each rocker joint pin comprising a pair of rolling members 1a, 1b,
The rolling members of each pair contact cylindrical surfaces having the same radius of curvature with each other so that they can roll with each other. These pins 1 connect a number of link plates 2 to each other to connect the endless link of the same specification.
Construct 3,4. Connect these endless link connectors 3 and 4 to pin 1
Is half of the pin arrangement pitch P ₀ (for example, 7.82 mm) The rocker joint pins of each link connector are inserted between the pins of the other link connector.
If there is a gap between the ends of the pins that have penetrated at this time, the gap is filled with the bush 5 (only one is shown for convenience in the drawing) to keep the relative position of the link connectors 3 and 4 in the longitudinal direction unchanged. Make it drip.

A V-shaped block 6 surrounding the juxtaposed link connectors 3 and 4 in the lateral direction is sequentially provided in the longitudinal direction of the link connectors 3 and 4 without any gap. For this reason, each V-shaped block 6 has a link connecting body.
A window 6a is formed for the holes 3 and 4 to pass therethrough. Each V-shaped block 6 is further provided with a projection 6b for partitioning between the windows 6a, so that the relative positions of the pins of the link connecting members 3 and 4 do not change. keep.
Note 1 The thickness b is the pin arrangement pitch P ₀ of the integer fraction of V-shaped blocks 6, preferably as a quarter or less, with the gap between the V-shaped block 6 will not happen, so that the work from running or sagging V Preferably, the shaped block 6 can be punched.

Further, as for the V-shaped block 6, as shown in FIG. 3, the width W in the pulley axial direction measured on the arrangement pitch line of the pins 1 is W =
Three different types of V-shaped blocks 6-1, 6-2, and 6-3 such as 30.0 mm, W = 30.05 mm, and W = 30.10 mm are used, and these three types of V-shaped blocks are basically the first. As shown in the figure, four pieces are arranged in the longitudinal direction of the link connecting bodies 3 and 4 as one pitch. At this time, the V-shaped blocks 6-1, 6-2 and 6-
In determining the width of 3, the following is taken into consideration.

That is, a case in which a power transmission belt which frictionally engages the pulley V-groove 7 as shown in FIG. 3 is stretched between the input and output pulleys 8 and 9 as shown in FIG. And the output pulley torque T ₀ is T ₀ = T ₁ · R _B −T ₂ · R _C Is represented by By the way, ΔW _B and ΔW _C change as the power transmission belt travels because V-shaped blocks of different widths are located at points B and C, and the output torque T ₀ also changes accordingly to cause torque fluctuation.

On the other hand, as described in JP-A-59-226730, the main frequency f of the noise generated during running of the power transmission belt is V, the belt running speed is P, and the substantial pin arrangement pitch is P. When three types of V-shaped blocks 6-1, 6-2 and 6-3 having different widths in the axial direction of the pulley are used as described above, the pitch P is not constant at the position where the pulley is wound, and changes variously. As a result, the noise level can be suppressed.

By the way, the noise level L and the torque fluctuation amount T of the belt meshing primary frequency were tested for each difference ΔW between the maximum value and the minimum value of the pulley axial width of the V-shaped blocks 6-1, 6-2 and 6-3. It was confirmed that the respective values changed with a tendency as shown in FIG. Fig. 5 shows that the transmission belt is
Experimental data when applied to a belt-type continuously variable transmission. The noise level L indicates a case where the vehicle traveled at a vehicle speed of 40 km / h.
The torque fluctuation amount T indicates a case where the speed ratio is 2.45 corresponding to the lowest speed ratio, and the sum (T ₁ + T ₂ ) of the pulley belt tensions T and T ₂ (see FIG. 4) is 500 kgf. . This fifth
As is apparent from the figure, it was confirmed that the effect was not changed even when the maximum difference ΔW of the V-shaped block width W was increased to a certain degree or more, and that the torque fluctuation was increased as the ΔW was increased. The perceived noise level and torque fluctuation level are L ₁ and T ₀ , respectively. Therefore, in order to suppress both the noise level and the torque fluctuation within the permissible range, the maximum difference ΔW of the V-shaped block width must be reduced. 0.08-0.13mm
Make sure it should be within the range.

From this, in the present invention, the maximum difference ΔW of the V-shaped block width is determined in the range of 0.08 to 0.13 mm so as to satisfy both the noise level and the torque fluctuation.

(Effects of the Invention) As described above, in the present invention, the maximum difference ΔW of the V-shaped block width is set to 0.
Since the width is set to 08 to 0.13 mm, the width in the axial direction of the pulley differs.
The torque fluctuation caused by the difference in the diameter of the pulley winding of these V-shaped blocks due to the use of two or more types of V-shaped blocks while sufficiently achieving the noise suppression effect by using more than one type of V-shaped blocks. Can be kept within allowable limits.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of an essential part showing an embodiment of the power transmission belt of the present invention, FIGS. 2 and 3 are respectively a longitudinal side view and a vertical front view of the essential part, and FIG. FIG. 5 is a region diagram showing the maximum difference in V-shaped block width that satisfies the noise level and torque fluctuation. DESCRIPTION OF SYMBOLS 1 ... Pin, 2 ... Link plate 3, 4 ... Endless link connection body 6 ... V-shaped block, 7 ... Pulley V groove 8 ... Input pulley, 9 ... Output pulley

Claims (1)

(57) [Claims] 1. A plurality of endless link connecting bodies each having a number of link plates connected to each other by pins, and the plurality of endless link connecting bodies are juxtaposed so that the positions of the pins are shifted, and these endless link connecting bodies are collectively arranged in the lateral direction. Surrounding and frictionally engaging the pulley V-grooves,
In a power transmission belt in which a plurality of V-shaped blocks having two or more types of pulley axial widths are sequentially provided in the longitudinal direction of the endless link connection body juxtaposed, the V-shaped block measured on an arrangement pitch line of the pins The difference between the maximum value and the minimum value of the pulley axial direction width is 0.08 to 0.13.
A transmission belt characterized in that it is set to mm.