JPS6152336B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuously variable transmission using a gear mechanism. Conventionally, mechanisms that can steplessly change the rotational speed of a rotating shaft have been considered, such as using a fluid coupling or making the rotating body of a pulley a conical body, but these mechanisms cannot respond to load fluctuations. Although it is good as a means of use when changing the number of rotations, it has the disadvantage that a constant number of rotations cannot be ensured. On the other hand, when gears are used to change gears, the power is transmitted reliably and is transmitted at the desired rotation ratio. I have to change gears accordingly.

The present invention has been conceived in view of the above, and provides a continuously variable transmission capable of steplessly changing speeds regardless of power transmission through a gear mechanism.

Hereinafter, the present invention will be explained with reference to an embodiment. The driving force is transmitted by reduction gears 1 and 2, and gear 2
drives the output shaft with the optimum reduction ratio at the shaft center. The present invention provides a means for steplessly changing the rotation of the output shaft with respect to the rotation of the gear 2.
In the figure, the output shaft is constructed integrally with the worm gear 3. The worm gear 3 is provided with multiple worm teeth 4, and a plurality of inductors 5 having lugs that mesh with the worm teeth 4 are arranged so as to surround the outer periphery of the worm gear in parallel to the axis of the worm gear. be done. This inductor 5 rotates around the worm gear 3 together with the gear 2, but all the inductors 5 are loosely fitted inside the gear 2, and the inductors 5 are easily meshed with the worm gear 4 and the inductor 5. There is at least one child, and the inductors on both sides of the child are either engaged or disengaged depending on their rotational position,
Many other inductor racks are constructed so that they do not mesh with the worm teeth 4. That is, the gear 2 is supported by a fixed bearing 6, and the piece 8 having the roller 7
is built in, and the piece 8 holds the inductor 5 slidably in the axial direction. 17 is a mounting pin for the roller 7.
In order to speed up understanding, the figure has been explained with the inductor 5 being held directly on the piece 8, but as shown in FIG. It is preferable to attach it loosely. The outside of the piece 8 is engaged with the guide ring 11. The guide ring is fixedly provided on the outside of the body of the gear 2 and guides the piece 8. A portion of the circular guide ring is continuously deformed inward by a gentle curve to form a timing cam portion 12. When the piece 8 comes to the timing cam portion 12, the piece moves inward along the guide ring 11. Only the inductor connected to the piece located on this timing cam portion 12 meshes with the worm teeth 4. When the piece 8 is in the circular part of the guide ring 11, the inductor 5 does not engage with the worm teeth 4, but when it starts to engage the timing cam part 12, there is a slight gap in the distal direction between the piece 8 and the sliding piece 9. The meshing timing of the worm teeth 4 is automatically adjusted by a small gap between the sliding piece 9 and the inductor 5, and the gear 2 is also adjusted when disengaging the worm teeth.
The clutch portion is disengaged when the rotating body corner b hits the inductor 5 and the inductor 5 is slightly inclined about the pin 10.

There are speed change plates 13, 1 near both ends of the worm gear 3.
3, and is arranged so that both ends of the inductor 5 move while contacting the speed change plates 13, 13. This speed change plate is donut-shaped and forms a surface that can accommodate the circular motion of the inductor, and is deformed in the axial direction to form an inclined surface. This angle of inclination is related to the angle of inclination of the worm teeth 4, and can be changed by changing the gear ratio. 3A and 3B show an example of a mechanism for changing the inclination angle by operating the speed change plates 13, 13. The speed change plates 13, 13 are provided with a speed change shaft 14; The speed change shaft 14 is rotated by the shown speed change lever 15. At this time, the gear shift shaft 1
By providing a helical guide 16 that changes its position in the axial direction as the inductor 4 rotates, the speed change surface that receives the end of the inductor 5 can always be kept in an optimal state even if the slope of the speed change plate 13 changes.

Next, the operation of the present invention will be explained. First, to explain the principle of the speed change of the present invention, consider the case where the inductor 5 moving along the inclined surface 18 of the speed change plates 13, 13 meshes with the worm tooth 4 at position a in FIG. As the inductor 2 rotates, the inductor 5 successively moves in parallel around the worm gear 3 at an angle of inclination β of the inclined surface 18. Assuming that the inclination angle of the worm teeth is α, when ∠β=∠α, the inductor 5 only slides along the surface of the worm gear 3 and no power is transmitted to the worm gear 3. When the inclination angle β of the surface of the speed change plate 13 is slightly increased with respect to the inclination angle α of the teeth 4 of the worm gear, the rack of the inductor 5 moves while sliding on the worm teeth 4, and the driving force is transferred to the worm gear 3. Since the rotation of the gear 2 is transmitted, the rotation of the gear 2 is transmitted at a reduced speed. When the inclined surfaces 18 of the speed change plates 13, 13 constitute a surface perpendicular to the rotation axis of the worm gear, the rack of the inductor 5 meshes with the worm teeth 4 and rotates without slipping, so that the rotation of the gear 2 is maintained as it is. The signal is transmitted to the worm gear 3. The variation range of the inclination angle β of the inclined surface 18 of the transmission plate 13 with respect to the inclination angle α of the teeth of the worm gear 3 is considered to be ∠α to 90°. Also, if ∠β is smaller than ∠α, the worm gear will reverse, and if ∠β is larger than 90°, the rotational speed will increase more than that of the drive input shaft, but there is a limit to its range.

Next, considering the gear ratio of the worm gear 3, in FIG. 4, the inclination angle β of the inclined surface 18 is A→B ₁ , A→
B ₂ , A → B ₃ ... Considering the case where A → B ₉ changes, when A → B ₁ , the gear ratio is 0. When A → B ₂ , the gear ratio is approx. 1/8. When A → B ₃ , the gear ratio is approx. 2/8 〓 When A → B _9, the gear ratio becomes 1, but of course the gear ratio can be changed steplessly even in the middle.

Based on the above-mentioned principle of speed change, the mechanism that changes the speed of the worm gear 3, which is the output shaft, from the drive gear 2 and transmits the power is a mechanism that changes the speed of the worm gear 3, which is the output shaft, and transmits power to the built-in piece 8 as the gear 2 rotates.
is guided by two guide rings 11 separately provided on the outside of the gear 2, and the piece 8 loosely holds the inductor 5, which has a rack that meshes with the worm teeth 4 of the worm gear 3, and the guide ring The inductor 5 is pressed against the worm teeth 4 only when the piece 8 passes through the timing cam portion 12 at one location of the worm gear 11.
As the gear 2 rotates, the inductor 5 meshes with the worm teeth 4 one after another and transmits power to the worm teeth.
At this time, the inductor 5 moves obliquely along the inclined surface 18 of the speed change plate 13, so that the rotation speed of the worm gear 3 is changed according to the above-mentioned speed change ratio.

In this way, the present invention provides a timing cam portion to mesh the inductor with the worm teeth, and the inductor itself moves on an inclined surface while transmitting power to the worm gear, and the speed is changed depending on the inclination angle. The above-mentioned structure and function of being able to adjust the ratio make it possible to perform stepless shifting, which was not possible with conventional gear mechanisms, and the shifting accuracy is extremely high in the gear ratio range of 0 to 1. It is expensive, and since it is a gear mechanism, it can reliably transmit power, and has the advantage of being able to be used for a long time because it has a large transmission force, little transmission loss, and little wear.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view for explaining an embodiment of the present invention, FIG. 2 is a side sectional view, and FIG. 3 is a front view of the speed change plate portion of FIG. 2 for explaining the speed change plate. B is a side view of FIG. A, FIG. 4 is a diagram for explaining the gear ratio, and FIG. 5 is a cross-sectional view for explaining the state of the inductor. 1, 2... Gear, 3... Worm gear, 4...
Worm tooth, 5... Inductor, 6... Fixed bearing, 7
...roller, 8...piece, 9...sliding piece, 10...
Pin, 11... Guide ring, 12... Timing cam section, 13... Speed change plate, 14... Speed change shaft, 1
5...Speed lever, 16...Spiral guide, 17...
...Pin, 18...Slanted surface.

Claims (1)

[Claims] 1 The output shaft is integrated with a worm gear, a plurality of inductors meshing with the worm gear are arranged parallel to the worm shaft, and are connected to the input shaft so as to rotate the outer periphery of the worm gear, and the inductors mesh with the worm gear. The guide ring of the inductor is continuously deformed inward by a gentle curve so that at least one of the inductors meshes with the worm gear at a specific rotational position, and many other inductors are released from the worm gear. and the inductor meshing with the worm gear moves along a required inclination angle with respect to the inclination of the teeth of the worm gear, while the inductor meshing with the worm gear passes through the specific rotational position as the input shaft rotates. A continuously variable transmission has both ends guided by a speed change plate, and can be changed steplessly by changing the inclination of the speed change plate.