JPS6257854B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a device for transmitting rotational motion from one shaft to another.

(b) Prior Art The following power transmission devices are generally considered as the above-mentioned power transmission devices.

a Attach cranks to both shafts and connect them with connecting rods.

b. Attach gears to both shafts and engage them directly or through intermediate gears.

c Fix pinions on both shafts and engage the movable racks.

d Attach chain sprockets or pulleys to both shafts and wrap the chain or belt around them.

Such methods are possible, but they have the following problems. First, method a,
When transmitting information between both supported shafts, the rotation angle that can be transmitted is limited to less than half a rotation, and the scope of application is narrow. b
Although the methods of and c can transmit a large angle, accurate tracking of the driving side cannot be expected due to the backlash of the teeth. Although it is possible to reduce the bump crash by using matching gears, it is still difficult to reduce it to zero. The method d has no problem in terms of transmission angle. However, if it is desired to reduce chain and timing belt backlash or belt slip, the tension in the chain or belt must be increased, and the shaft support structure must be strengthened. Furthermore, even if the bearing is strengthened, it is difficult to avoid problems such as uneven wear of the bearing. The device described in Japanese Utility Model Publication No. 55-39126 provides a suggestion for transmitting power between shafts without buckling, but if the flexible shaft stretches as a result of long-term use, However, there is no proper way to correct this. Apart from this, a device disclosed in Japanese Patent Application Laid-Open No. 49-127070 uses a band to transmit power.
Since a spring body is interposed in the middle, it seems that the problem can be solved if it is limited to only the backlash, but no matter how accurate the correspondence between the rotation angle of the rotation axis and the straight line movement distance of the rod is created. (Because only the spring absorbs part of the amount of rotation or movement), it cannot be used in situations where precise movement control is required, such as in driving the arm of an industrial robot.

(c) Problems to be Solved by the Invention The present invention completely eliminates backlash in a device that transmits a relatively large amount of rotation from one shaft to another, and does not cause problems such as uneven bearing wear. First, it is an object of the present invention to provide a device that can easily perform backlash zero correction.

(d) Means for solving the problems In the present invention, three members are prepared: a driving drum, a driven drum, and a transmission rod. Then, a transmission tape for forward rotation and a transmission tape for reverse rotation are wrapped around the driving drum and the driven drum, respectively. The winding directions of the forward rotation transmission tape and the reverse rotation transmission tape are reversed, and one end of each tape is fixed to the drum, and the other end is pulled out from the drum and fixed to the transmission rod. Furthermore, each of the driving drum and the driven drum is constituted by a unit drum wrapped with a transmission tape for forward rotation, and a unit drum wrapped with a transmission tape for reverse rotation, and these unit drums are configured such that:
They are stacked so that they can be angularly shifted from each other around the axis of rotation, and then connected using fastening means.

(E) Function If the transmission tape for forward rotation and the transmission tape for reverse rotation are stretched taut, rotation can be accurately transmitted from the driving side to the driven side without rattling. There is also no limit to the angle of transmission as there is with a crank. Further, since the tension of the tape can be canceled out by the transmission tape for forward rotation and the transmission tape for reverse rotation, unnecessary bending stress is not generated between the shafts. When slack occurs in the tape, the slack can be easily corrected by rotating the unit drums relatively to take up the slack and fixing the tape again using the fastening means.

(f) Example In the figure, 1 is a driving shaft, 2 is a driven shaft,
A driving drum 3 and a driven drum 4 are each provided at the upper end. The driving drum 3 is in the form of a stack of unit drums 5 and 6, the lower unit drum 5 is fixed to the driving shaft 1, and the upper unit drum 6 is loosely fitted to the driving shaft 1. ing. The unit drum 6 is fixed to the unit drum 5 with bolts 7, 7, and the holes through which the shafts of the bolts 7, 7 pass are circular arc holes 8, 8 centered on the axis; By loosening the angles of the unit drums 5 and 6, it is possible to shift the angles of the unit drums 5 and 6 within the range of the lengths of the arcuate holes 8 and 8. In order to facilitate the operation of shifting the angle, a hole 9 into which the tip of a screwdriver or the like is inserted is formed on the circumferential surface of the unit drums 5 and 6. Similarly, the driven drum 4 also has the driven shaft 2.
The unit drum 11 is loosely fitted to the driven shaft 2 and connected to the unit drum 10 by bolts 12, 12 passing through arcuate holes 13, 13. A hole 14 into which a driver or the like is inserted is also formed on the peripheral surface of the unit drums 10, 11. Unit drum 5, 6, 10, 11
all have the same diameter.

Now, one steel tape is attached to each of the unit drums 5, 6, 10, and 11. The unit drum 5, 11 is combined with the forward rotation transmission tape 1.
5, 16, one end is fixed to the drum circumferential surface 17, 18
In addition, the forward rotation transmission tape 15 is wound around the drum counterclockwise when viewed from above, and the forward rotation transmission tape 16 is wound around the drum clockwise when viewed from above. Tape 15, 16
The other end is pulled out for a predetermined length from the drum and connected to the transmission rod 1.
9 are fixedly attached 20 and 21. The transmission rod 19 is made to have sufficient rigidity. Reversing transmission tapes 22, 23 are fixed to the other unit drums 6, 10 24, 25.
Then, the reversing transmission tape 22 is wound clockwise when viewed from above, and the reversing transmission tape 23 is wound and pulled out counterclockwise when viewed from above, and fixed to the transmission rod 19 26.
27.

With the above configuration, when the driving shaft 1 rotates clockwise, the driving drum 3 winds up the forward rotation transmission tape 15, and the forward rotation transmission tape 15 moves the transmission rod 19 to the right in the figure. The forward rotation transmission tape 16 rotates the driven drum 4 while being pulled out from the driven drum 4, and the driven shaft 2 also rotates accordingly. Conversely, when the driving shaft 1 rotates counterclockwise, the driving drum 3 winds up the reversing transmission tape 22, pulls the transmission rod 19 to the left, and pulls out the reversing transmission tape 23 from the driven drum 4. Driven shaft 2
Rotate counterclockwise.

Now, if the steel tape stretches as a result of long-term use and misalignment occurs in the movement of the driving shaft 1 and driven shaft 2, loosen the bolts 7 and 12 and insert the screwdrivers 28 and 29 into the holes 9 and 14 as shown in Figure 2. are inserted and twisted together to cause the unit drums 5, 6, 10, and 11 to rotate relative to each other for each combination. After taking up the slack in the transmission tapes 15, 16 for forward rotation and the transmission tapes 22, 23 for reverse rotation, tighten the bolts 7, 12.
The backlash zero correction is completed.

(G) Effects of the Invention According to the present invention, a relatively large amount of rotation can be transmitted without backlash, and the backlash can be easily corrected to zero. Furthermore, unlike wrapped conduction, there is no need to apply tension between the two shafts, so the life of the shaft support structure can be extended.

[Brief explanation of the drawing]

The figures show an embodiment of the apparatus of the present invention, with FIG. 1 being a perspective view and FIG. 2 being a partially enlarged perspective view. 3... Driving drum, 4... Driven drum, 5,
6,10,11...Unit drum, 19...Transmission rod, 15,16...Transmission tape for forward rotation, 22,2
3... Reverse transmission tape, 7, 12... Bolt (fastening means).

Claims (1)

[Claims] 1 Equipped with a driving drum and a driven drum whose rotation axes are parallel to each other, and a transmission rod, and on the outer periphery of both drums, a transmission tape for forward rotation and a transmission tape for reverse rotation are attached to each other with one end fixed to the drum. The other end of these tapes is pulled out a predetermined length from the drum and fixed to the transmission rod, and each of the driving drum and driven drum is connected to a unit drum wrapped with the transmission tape for forward rotation and a unit drum wrapped with the transmission tape for reverse rotation. A motion transmission device consisting of a unit drum wrapped with a transmission tape, which unit drums are stacked so as to be mutually angularly shifted about the axis of rotation, and then connected by a fastening means.