JPS5846250A - Belt type stepless transmission - Google Patents

Abstract

PURPOSE:To increase the power transmission efficiency by transmitting the movement of a driving side slide pulley to a spring for pressing a driven side slide pulley to increase the frictional force between the belt side surface and the driven side slide pulley upon the low speed operation. CONSTITUTION:Upon performing the speed change operation, when a lever 13 is actuated, the movement of the driving side slide pulley 8 is transmitted from a shift fork 11, a shift shaft 12 and a short arm 26 at the driving side to a short arm 25, a shift shaft 24 and a shift fork 23 through a shaft rod 27 at the driven side, and further transmitted to a bearing cover 22, a bearing 21 and a base ring 20. That is, by moving together the driving side slide pulley 8 and the base ring 20, a predetermined pressing force is retained at a spring 18 even at any speed changing time, and hence a constantly excellent power transmission efficiency can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a belt type continuously variable transmission device that has excellent power transmission efficiency at low speeds.

As a belt-type continuously variable transmission, a so-called double variable pitch transmission as shown in FIG. 1 is generally known. That is, in FIG. 1, the device 1 arranges the drive side speed change pulley 2 and the driven side speed change pulley 3 so that their axes are parallel and the belt center lines of both pulleys 2.3 are aligned. One pulley is placed in the pulley box 4, and a belt 20 is wound around both the pulleys 2 and 3. Further, the drive side gear change pulley 2 is mounted on both side wall bearing portions 5, 5'- of the upper pulley box 4a.
A fixed pulley 7 and a sliding pulley 8 are provided facing each other on the input shaft 6 supported on the ζ axis, and a bearing 9 and a bearing cover 10 are fitted to the boss portion 8a of the sliding pulley 8, and the bearing cover 10 is fitted. A tuning fork-shaped shift fork 11 is fixed so as to be sandwiched from the outside on both sides, and the shift fork 11 is further connected to the input shaft 6Kf! The shift shaft 12 is attached to a substantially central portion of a shift shaft 12 extending in the right direction, and a lever 13 is attached to an end of the same shaft 12.

In addition, the driven side speed change pulley 3 has a sliding pulley 16 and a fixed pulley 17 installed opposite to each other on the output shaft 15 supported by both side wall bearings 14 and 14'iC of the lower pulley box 4b. A base ring 19 is attached to the output shaft 15 for interposing a spring 18 in the boss portion 161 and compressing and supporting the spring 18 by a predetermined amount to press and bias the sliding pulley 16 toward the fixed pulley 17. Fixed configuration. Therefore, in a speed change operation, the driving side sliding pulley 8 is moved in the direction of the arrow by actuation of the lever 13, and at the same time, the driven side sliding pulley 16 is moved in the direction of the arrow by the elastic force (i.e., pressing force) of the spring 18. This is done by changing the belt diameter of the driven side speed change pulley 3.

However, when the output shifts to a low speed (i.e., when the belt diameter of the driven speed change pulley 3 is large), the spring 18 becomes more stretched, and due to the spring's unique elastic properties, its elastic force increases. Since the suppressing force becomes extremely weak, the frictional force between the side surface of the belt 20 and the side surface of the driven speed change pulley 3 decreases accordingly, and the transmission efficiency is lower than, for example, when pressing with a constant hydraulic pressure. The drawback is that it gets worse.

The present invention has been made in view of these circumstances, and its purpose is to provide a belt-type continuously variable transmission that eliminates the above-mentioned drawbacks and has excellent power transmission efficiency at low speeds.

However, the continuously variable transmission device of the present invention, which has achieved these objectives, has a drive-side speed change pulley in which a fixed pulley and a sliding pulley are provided relative to each other on the input shaft, and a fixed pulley and a sliding pulley on the output shaft. If a driven side speed change pulley, which is made up of pulleys arranged opposite to each other, are placed side by side in a direction in which their axes are parallel to each other, and a belt is wound around the dual speed pulley, the same number ζ and driven side sliding pulley will be obtained. In the belt-type continuously variable transmission of the double speed pitch type, which is constructed by attaching a spring to the driven side sliding pulley to press the output shaft 8 toward the fixed pulley side, the base ring for pressing the spring provided with the output shaft 8 is provided. Each shift fork, which is slidably inserted into the output shaft, fits the bearing and the bearing cover onto the pace ring, and fixes the bearing cover and the bearing cover of the driving side mm pulley, respectively, is attached to the input/output shaft. The main feature is that the shift shaft is attached to shift shafts extending in the overlapping direction, and both shift shafts are connected by a link mechanism.

The configuration and effects of the present invention will be explained below based on the drawings, but the drawings show an example of specific implementation of the present invention, and the present invention is not limited to these illustrated examples, but can be applied to the preceding and following examples. Changing the shape of the supporting parts or omitting part of the design according to the purpose are all within the technical scope of the present invention.

FIG. 2 is a partially cross-sectional schematic front view showing an embodiment of the present invention.
The device 1 includes a drive side speed change pulley 2 and a driven side speed change pulley 3.
is installed inside the pulley box 4, and a belt 20 is wound around both pulleys 2 and 3.
In terms of its internal configuration and its basic structure, the Hontsuri Butsei has no place in common with the conventional example shown in Fig. 1. Therefore, the following description will focus on the features of the present invention. That is, the driven inversion speed pulley 3 is
An fII pulley 16 and a fixed pulley 17 are provided oppositely to each other on the output shaft 15, and the boss portion 16 of the sliding pulley 16 (:
X) A 9 ring 18 is inserted, a pace ring 2o for supporting the spring 18 is loosely fitted, and a bearing 21 and a bearing force /(-22) are fitted on the outer circumference of the ring 20, and The bearing cover 2.2 is pulled in from the outside of both structures and fixed with a tuning fork-shaped shift fork 23, and the shift fork 23 is placed approximately in the center of the shift shaft, which is extended one length perpendicularly to the output shaft 15. Furthermore, a short arm 2 is attached to the shift shaft 24.
The arm 25 and a short arm 26 fixed to the driving side shift shaft 12 are linked via a shaft m27.

Therefore, when the lever 13 is actuated to perform a speed change operation, the movement of the driving side sliding pulley 8 is caused by the movement of the driving side shift fork 11. It is transmitted from the shift shaft 12 and short arm 26 via the support rod 27 to the short arm 25 on the driven side, the shift shaft 24 and the shift fork 23, and is further transmitted as it is to the bearing cover 22, bearing 21 and base ring 20. That is, by setting both the driving side sliding pulley 8 and the base ring 20 at Sd, the spring 18 is configured to maintain a constant pressing force during any speed change operation.

Therefore, when shifting to a low output speed (i.e., when the belt diameter of the driven side shifting pulley 3 is large), the driven side sliding pulley 16
Even if the spring 18 moves significantly in the direction of the arrow,
The elastic force, that is, the suppressing force is well exerted, and good power transmission efficiency can be obtained, for example, as in the case where the sliding pulley 16 is pressed with a constant hydraulic pressure.

The present invention has been constructed as described above, but the point is that the movement of the driving side sliding pulley is directly transmitted to the station spring that presses the driven side pulley by a simple mechanism, so that the belt side surface during low speed operation is The frictional force between the driven side pulley and the side of the pulley is large (which increases the power transmission efficiency).Furthermore, the reaction force of the spring acts on the driving side sliding pulley via the ring mechanism, so there is little need for speed increase operations. It is easy to operate because it can be operated by force.Also, the link mechanism is the center of the above-mentioned unique structure, and it is simpler than a hydraulic control mechanism, for example, so it is possible to make the device more compact. It is possible and economical.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional schematic front view showing a conventional belt type continuously variable transmission, and FIG. 2 is a partially sectional schematic front view showing a belt type continuously variable transmission according to the present invention. l... Belt type continuously variable transmission, 2... Driving side speed change pulley, 3-- Driven side speed change pulley, 4--Boolean box,
5.5', 14.14'-Bearing part, 6-・Input shaft, 7-
・・Drive side fixed pulley, 8・−Drive side sliding pulley, 9° 21−・Bearing, 10, 22−・・Bearing cover, 11.
23...Shift fork, 12t 24"'shift shaft, 13...Lever, 15-...Output shaft, 16-...
- Driven side sliding pulley, 17- - Driven side. Fixed boo 9,i
s- Spring, 20 Base ring, 25.
26- Short arm, "27-・Axle rod.

Claims (1)

[Claims] (1) Input shaft - Driving side speed change pulley, which is made up of an upper fixed pulley and a sliding pulley, and output shaft &cii! A driven side speed change pulley, which is made up of a fixed pulley and a sliding pulley, are arranged parallel to each other in the direction parallel to the axis, and a belt is wound around the double speed pulley, and the driven side sliding pulley is placed on the fixed side. In a double variable pitch belt type continuously variable transmission configured by attaching a spring that presses the driven side sliding pulley to the output shaft base, the base ring of the spring that presses the driven side sliding pulley is attached to the output shaft base. and use the pace ring as a bearing inner cover. #Applicable to science and bearing outer cover)-
A shift fork that fits into the sling and also fixes the bearing outer cover and the bearing outer cover of the driving side sliding pulley is attached to the shift shaft extending vertically from the input/output rotation, and then both shift A belt-type continuously variable transmission characterized in that the two are connected by a link mechanism.