JPH04165148A - belt drive device - Google Patents

Abstract

PURPOSE:To provide a rotary motion of high accuracy without using a highly accurte expensive prime mover by arranging an intermediate pulley having an eccentricity so that the nonuniformity in the rotation of a drive wheel and the nonuniformity in the rotation due to the eccentricity of the intermediate pulley are reverse in phase to each other. CONSTITUTION:An intermediate pulley 6 is provided for driving an idler without load or a load not requiring accuracy of nonuniformity in rotation, constituted to have an intentional eccentricity, and installed having the pitch circle diameter rotating at the same frequency with that of the main frequency component of the nonuniformity in the rotation of a drive wheel 1 and with its phase reverse to the phase of the drive wheel 1. By making the pitch circle diameter of the drive wheel 1 same as that of the intermediate pulley 6, nonuniformity in the rotation of the drive wheel 1 is absorbed. As a result, the nonuniformity in the rotation of the drive wheel 1 is lessened and absorbed to transmit an accurate rotation to a driven wheel 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a belt drive device used in the field of precision drive technology for office automation equipment, industrial equipment, and the like.

[Prior Art] As a belt drive device that transmits the rotation of a prime mover from a prime mover to a driven vehicle via a belt to drive a driven vehicle, for example, the system shown in FIG. 7 and the system shown in FIG. The method shown here has been known in the past. That is, the system shown in FIG. 7 transmits the rotation of the prime mover 1 to one belt 2,
The belt 2 drives driven wheels 3 and 4, which are driven elements.On the other hand, in the system shown in FIG. The driven wheels 3 and 4 are individually driven by a belt 2. Note that 5 indicates a tightener.

However, in the case of the system shown in FIG. 7, the driven wheel 3 located upstream of the driving vehicle 1 functions as an intermediate pulley with respect to the driven wheel 4 located downstream of the driving vehicle 1.
If there is eccentricity in the belt 2, the change in the trajectory of the belt 2 is absorbed by the tightener 5, resulting in uneven rotation of the driven wheel 4. That is, when the driven wheel 3 is eccentric to the outside by an amount of eccentricity Δr as shown by the two-dot chain line in FIG. It gets faster. Therefore, when precision driving is required, it has been common to adopt the system shown in FIG. 8, which does not require an intermediate pulley between the motive wheel 1 and the driven wheel 3.4.

[Problems to be Solved by the Invention] However, since the purpose of the belt drive device is to accurately transmit the rotation of the driving vehicle to the driven vehicle,
If the driven vehicle is required to have precise rotational motion without uneven rotation, it is essential to improve the accuracy of the rotational unevenness of the prime mover itself, so it is expensive to improve the accuracy of the prime mover including the prime mover. The drawback is that it becomes something else.

The present invention is intended to provide highly accurate rotational motion without using a highly accurate and expensive prime mover by absorbing rotational unevenness of the prime mover.

Means for Solving Problem 1 - 1 In order to solve problem L, the present invention provides a belt drive device that transmits the power of a driving type to a driven vehicle by a belt, in which uneven rotation of the driving vehicle is solved. The intermediate pulley, which rotates at the same frequency as the frequency of , and whose eccentricity is rj, is placed on the tension side of the belt. The configuration is such that the arrangement is 1-5 so that the phase is slightly opposite to that of the other.

[Function] If a rotational unevenness with the same frequency as the rotational unevenness struck by the driving force is intentionally generated by an intermediate boolean, the phase of each rotational unevenness will be opposite. ,
As a result of the uneven rotation of the prime mover being alleviated, U'i dense rotational motion can be obtained with an inexpensive configuration.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In a belt drive device, the power of a prime mover 1 is transmitted by a belt 2 to a driven wheel 11 that requires precision driving. An intermediate pulley 6 is provided on the side (first side in the direction of rotational force of the prime mover 1) to absorb uneven rotation of the prime mover 1. 5 designates a tie-ner similar to that shown in FIGS. 7 and 8.

To be more specific, the intermediate pulley 6 is an idler with no load or is designed to drive a load that does not require accuracy of rotational unevenness, and the eccentricity that was previously and intentionally provided is reduced by r'-. Furthermore, it is installed so that the diameter of the pitch circle that rotates 1ri1 at the same frequency as the main frequency component of the rotational unevenness of the motor vehicle 1 is also in the opposite phase. In this embodiment, by making the pitch circle diameter of the prime mover 1 and the pitch circle diameter of the intermediate pulley 6 the same, it is possible to cope with rotational irregularities that occur in one rotation of the prime mover 1.

Next, an example of the bell I/drive device of the present invention having the above structure will be explained.
The single motion principle will be explained with reference to FIG.

Figure 2 (A) shows the rotational unevenness caused in the driven wheel 1 due to rotational unevenness of the prime mover 1, approximated by a sine wave.
It is. Conventionally, this increases the viscosity of the rotation of the prime mover, including the prime mover 1, and cannot be eliminated.
It is something that Note that ``■'' indicates a time interval of j cycles.

Figure 2 (B) shows the state of rotational irregularity intentionally caused by the eccentric intermediate pulley 6 inserted between the prime mover 1 and the driven wheel 4, and the solid lines indicate the same phase. Also, the wavy lines indicate the times when the phases are opposite.

The magnitude of rotational unevenness is determined by the amount of eccentricity, and the frequency is determined by the number of rotations of the intermediate pulley 6. Furthermore, since the prime mover 1 and the intermediate pulley 6 are connected by the belt 2, the phase with respect to the uneven rotation by the prime mover 1 is
It is determined by the mounting angle of the intermediate pulley 6 relative to the angle of the intermediate pulley 6. , Fig. 2C) shows the state of rotational unevenness that occurs in the driven wheel 4 when the rotational unevenness of Fig. 2(A) (Bl) is combined. It can be seen that rotational unevenness is greatly promoted, and the two are combined, and the two are relieved.

Therefore, in the present invention, the intermediate pulley L, which has the same frequency as the frequency of the rotational unevenness of the prime mover 1, is inserted into the tension side of the belt 2 between the prime mover 1 and the lucky moving wheel 10. By making the phases of each of the rotational irregularities intentionally generated in the reverse phase ζ), this mechanism absorbs the rotational irregularities of the prime mover 1 and transmits precise rotational motion to the driven wheel 4. Kokichi can do it.

Figure 3 shows a model of the actual machine on which the experiment of y) was conducted to alleviate the uneven rotation of the motive vehicle 1.
Two intermediate pulleys 6.6' are arranged on the tension side of the bevel 4.2 between the driven wheel 4 and the driven wheel 4.

Note that the frequency of the motive vehicle l and the intermediate pulley () is 1.
25o7, intermediate pulley 6' is 7,7511z, driven wheel 4 is 0.511. , Toshide. , Fig. 71 (N to C) shows the state of the phase angle of the motive wheel 1 and the intermediate pulley 6 at every 45° in the above-mentioned actual machine, and Fig. 5 (A
) to C) indicate the state of uneven rotation at that time. Also, the 6th
The figure is an enlarged view of FIG. 5C) which is representative of FIGS. 4 l) The rotation unevenness that occurs in the driven wheel 1 is reduced by the intermediate pulley 6'.
J Length d-8 As is clear from FIGS. 1 to 6, these intermediate pulleys 6.
By making the rotational irregularities of 6' interact so that they do not cancel each other out, high-precision rotational motion can be obtained even with a low-precision, inexpensive prime mover.

Incidentally, it is known to use idlers within belt drives. Also, even if the eccentricity of A.Idler is not intentional, it is more or less naturally eccentric. In addition, there are cases where the drive vehicle and the (;'x-phase sub-adjustment) are installed so that they are in opposite phases by chance. The present invention is characterized by intentional insertion and placement in order to suppress unevenness.

The embodiment shown in Fig. 1 shows a case where four intermediate pulleys are arranged between the driving vehicle and the driven car, and the actual model shown in Fig. 3 shows a case where two intermediate pulleys are arranged.
Of course, the number can be freely selected and various changes can be made without departing from the gist of the invention.

[Effect of the Invention 1] As described in 1-1 above, the belt drive device of the present invention has a frequency that is the same as the frequency of uneven rotation of the prime mover on the tension side of the belt between the prime mover and the auspicious wheel. so that it rotates,
At least one intermediate pulley with eccentricity is arranged so that the uneven rotation of ~'' is in the opposite phase, so the intermediate pulley can absorb and absorb the rotational unevenness of the 0 drive vehicle. Accurate and without the use of expensive prime movers:
:+ It exhibits the excellent effect of being able to perform rotational motion with high precision and providing an inexpensive device.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the heddle drive device of the present invention, and Fig. 2 shows the state in which uneven rotation occurs.
(B) is the rotational unevenness caused by the driving wheel on the driven wheel, (B) is the rotational unevenness caused by the intermediate pulley on the driven wheel, (C)
Figure 3 shows the rotational unevenness after combining (A) and (B), Figure 3 is a model diagram of the actual machine, and Figure 4 (A, Figures 5 (A) to C) showing phase angle deviations are shown in Figure 4 (1'Q~).
Figure 6 shows the measured values of rotational unevenness by an actual machine corresponding to
The figure is an enlarged view of Figure 5C), and Figures 7 and 8 are both schematic diagrams showing examples of conventional belt drive devices.
・Motor vehicle, 2 ・・Belt, 4・Driven vehicle, 6,6'...
・Middle pulley.

Claims (1)

[Claims] (1) In a belt drive device in which the power of a prime mover is transmitted to a driven vehicle by a belt, an intermediate pulley having an eccentricity that rotates at the same frequency as the frequency of uneven rotation of the prime mover is attached to the belt. A belt drive device characterized in that the belt drive device is arranged such that rotational irregularities caused by the driving wheel and rotational irregularities caused by eccentricity of the intermediate pulley are in opposite phases to each other on the tension side of the belt drive device.