JPS63120953A - Friction type continuously variable transmission - Google Patents

Abstract

PURPOSE:To prevent any wear in the transmission in the caption by mounting a passive bevel gear which engages with an active bevel gear in a transmission case and fitting and holding the small diameter end side of a taper cone to the passive bevel gear, so that said small diameter end side can transfer torque, and freely slide in the direction of the shaft center line. CONSTITUTION:A taper cone 2 is shifted along its rotary shaft center line P in the direction toward a small diameter side so that its taper face 2b can make pressure contact with an output rotary body 6. A passive bevel gear 3 which engages with an active bevel gear 4 is mounted in a transmission case M. The small diameter end side of the taper cone 2 is fitted and held to the passive bevel gear 3 so that said small diameter end side can transfer a torque, and freely slide in the direction of a shaft center line. Thereby, even if the shifting distance in the direction toward the small diameter side the taper cone is in excess of the predetermined distance, the face pressure between both gears is increased so that any wear can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a tapered cone that rotates around an input shaft supported within a transmission case in conjunction with a driving bevel gear of the input shaft, An output rotating body that can come into contact with the tapered surface of the taper cone is integrally rotatably and slidably fitted onto an output shaft that is arranged concentrically with the input shaft, and The present invention relates to a friction type continuously variable transmission equipped with a pressing device that presses the tapered surface against an output rotating body by moving the tapered surface in a small diameter direction along its rotation axis.

[Conventional technology]

In this type of friction type continuously variable transmission, as shown in Figure 3,
The drive bevel gear (4) of the input shaft (1) causes the taper cone (2) to rotate on its own axis, and the taper cone (2) is moved in the direction of the small diameter along its rotational axis (P2) to taper. The surface (2b) was pressed against the outer periphery of the output rotating body (6), and the rotational power of the taper cone (2) was transmitted to the output rotating body by the frictional force. Due to such a structure, when the taper cone (2) is moved, the passive bevel gear (3) fixed to the taper cone (2) also moves together.

[Problem that the invention seeks to solve]

However, in the friction type continuously variable transmission having the structure described above, the thrust force of the taper cone (2) is applied between the driving bevel gear (4) and the passive bevel gear (3) during operation. When the amount of movement of the taper cone (2) exceeds a predetermined amount, the surface pressure on both gears (4) and (3) increases rapidly, causing increased wear and noise.

Therefore, the present invention takes these circumstances into consideration and aims to prevent as much as possible the wear and noise that occur as the taper cone moves in the direction of the smaller diameter.

[Means for solving problems]

The characteristic configuration of the present invention, which has been made to achieve the above object, is that a transmission case supports a passive bevel gear that meshes with a driving bevel gear fixed to an input shaft, and torque is transmitted to the passive bevel gear through the small diameter end side of the tapered cone. It is possible to fit and support it so that it can slide in the axial direction, and its functions and effects are as follows.

[For production]

In other words, since the taper cone is fitted and supported by the passive bevel gear so that it can slide in the axial direction, even if the tapered surface of the taper cone is moved in the direction of the small diameter in an attempt to press the output rotating body with the pressing device, the Pressure does not act on the passive bevel gear, only the taper cone moves. Therefore, the passive bevel gear transmits the rotational power of the driving bevel gear to the taper cone while maintaining its position.

[Effect of idea]

As described above, according to the present invention, even if the amount of movement of the taper cone in the small diameter direction exceeds a predetermined amount, the surface pressure of both gears does not increase, making it possible to effectively suppress wear and noise.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows the mission of an agricultural machine, which is equipped with a tapered cone type friction type continuously variable transmission (A) and a constant mesh type gear transmission (B) in an interlocked state.

The friction type continuously variable transmission device (A) will be explained.

A plurality of taper cones (2) are arranged concentrically around an input shaft (1) that receives rotational power from the engine side, and the shaft portion (2a) on the small diameter end side of the taper cone (2) is connected to a passive bevel gear (3). are spline-fitted to be able to transmit torque and to be slidable in the direction of the rotation axis (P), and the passive bevel gear (3) is engaged with the driving bevel gear (4) fitted to the input shaft (1). The rotational power of the human power shaft (1) is transmitted as the rotational power of the taper cone (2) via both bevel gears (3) and (4). Further, an output cylinder shaft (5) is fitted onto the input shaft (1) so as to be relatively rotatable, and a disc-shaped output rotating body (6) is slid onto the cylinder shaft (5) at its boss. The tapered surface (2b) of the tapered cone (2) is movably spline-fitted and
can be press-contacted to the outer periphery of the output rotating body (6). That is, by installing a spring (14) as a pressing device on the large diameter side of the taper cone (2), the taper cone (2) is urged toward the small diameter side along the rotational axis, and the urging force is applied to the output rotation. This is converted into a pressure force against the body (6). Then, the rotational power of the taper cone (2) is transmitted to the output rotating body (6) by the frictional force generated at that time, and
By sliding the output rotating body (6) and changing the contact position on the tapered surface (2b), the power is transmitted at a variable speed, thereby eliminating the rotational power of the input shaft (1). The speed can be changed stepwise and continuously and transmitted to the cylinder shaft (5).

In addition, as shown in FIG. 1, the taper cone (2) is
Since it is slidably fitted and supported by the passive bevel gear (3), even if the taper cone (2) moves in the small diameter direction along the rotation axis, its biasing force will not act on the passive bevel gear (3). do not. Therefore, the surface pressure at the engagement portion between the driving bevel gear (4) and the passive bevel gear (3) does not increase, and therefore wear and noise are always kept low.

The gear transmission (B) includes a first PTO shaft (7).
, transmission shaft (8), second PTO shaft (9), second PTO shaft (
9) and an integrated output shaft (10) are arranged in parallel below the input shaft (1) and the cylindrical shaft (5). Then, the rotational power of the cylinder shaft (5) is shifted through the transmission shaft (8) into four stages of forward and backward movement, and the output shaft (10) and the second PTO shaft (
9) The rotary power of the input shaft (1) and the rotary power of the output shaft (10) obtained from the engine side can be selectively transmitted.

[Brief explanation of the drawing]

The drawings show an embodiment of the friction-type continuously variable transmission according to the present invention, in which Fig. 1 is a longitudinal side view of a Taber cone, Fig. 2 is a longitudinal side view of a transmission case, and Fig. 3 is a longitudinal cross-section of a conventional Taber cone. FIG. (1)...Input shaft, (2)...Taber cone, (2b)...Tapered surface, (3)...
...Passive bevel gear-1 (4)...Motive bevel gear-1 (5)...Output shaft, (6)...
...Rotating body for output, (M) ...Mission case, (P) ...Rotating shaft core.

Claims (1)

[Claims] A taper cone (2) that rotates on its own axis in conjunction with the driving bevel gear (4) of the input shaft (1) is arranged around the input shaft (1) supported in the mission case (M). ) is capable of contacting the tapered surface (2b) of the output rotary body (6), which is integrally rotatable with respect to the output shaft (5) arranged concentrically with the input shaft (1), and is slidable. A pressing device is provided, which is movably fitted to the outside and moves the tapered cone (2) in a small diameter direction along its rotation axis (P) to press the tapered surface (2b) into contact with the output rotating body (6). In this friction type continuously variable transmission device, a transmission case (M) supports a passive bevel gear (3) that meshes with a driving bevel gear (4) fixed to the input shaft (1), and the small diameter of the taper cone (2) A friction type continuously variable transmission device whose end side is fitted and supported by the passive bevel gear (3) so as to be able to transmit torque and to be slidable in the axial direction.