JP2014043941A - Belt type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt type continuously variable transmission that enables high-speed rotation at low cost.SOLUTION: The belt type continuously variable transmission comprises a first actuator 100 driven by electric power and a second actuator 500 driven by centrifugal force associated with the rotation of a movable sheave 207. The movable sheave 207 has a cylindrical part 210. A rolling bearing 208 is arranged on the outer peripheral surface of the cylindrical part 210 so as not to axially overlap with the second actuator 500, and the first actuator 100 advances/retreats the movable sheave 207 via the rolling bearing 208.

Description

  The present invention relates to a belt-type continuously variable transmission having a primary pulley and a secondary pulley around which a V-belt is wound, and the outer diameters of the winding regions where the V-belt is pressed against the primary pulley and the secondary pulley are variable. .

Conventionally, as a belt-type continuously variable transmission, for example, a device disclosed in Patent Document 1 is known. The device of Patent Document 1 is a belt-type continuously variable transmission having a fixed sheave and a movable sheave movable with respect to the fixed sheave, and a V-belt is wound between the sheaves. It has a single control mechanism with a single actuator to move.
In the conventional continuously variable transmission described above, the movable sheave is moved by a single actuator and a single control mechanism. Therefore, when the power for moving the movable sheave is increased, a single actuator is used. In addition, there is a tendency that the single control mechanism is increased in size, and as a result, there is a difficulty that the belt type continuously variable transmission is easily increased in size.

  In order to solve this problem, for example, in Patent Document 2, in addition to the conventional electric actuator (hereinafter referred to as the first actuator), the first actuator is used in cooperation with the first actuator to move around the rotation axis of the movable sheave. A belt-type continuously variable transmission having a second actuator that includes a plurality of arranged centrifugal weights and a ramp plate that moves the movable sheave to the centrifugal weight by a centrifugal force accompanying the rotation of the movable sheave has been proposed. As a result, the power for moving the movable sheave can be increased.

JP 2009-79759 A (see FIG. 37) JP 2012-47292 A

However, in the belt-type continuously variable transmission described in Patent Document 2, the rolling bearing is disposed radially outside the ramp plate and the movable sheave, and the first actuator operates the movable sheave via the rolling bearing. It has become. For this reason, the size of the rolling bearing is increased, which causes problems such as not only an increase in the size of the apparatus but also a reduction in the allowable rotational speed of the rolling bearing and an increase in cost.
Accordingly, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and an object thereof is to provide a belt type continuously variable transmission that allows high rotation at low cost.

  To achieve the above object, a belt-type continuously variable transmission according to an embodiment includes a fixed sheave fixed to a pulley shaft, and a movable sheave supported by the pulley shaft so as to be movable along an axial direction. A primary pulley and a secondary pulley in which a pulley groove is formed between the fixed sheave and the movable sheave, an endless V-belt wound between pulley grooves of the primary pulley and the secondary pulley, A first sheave that moves the movable sheave of the primary pulley along the axial direction via a link mechanism to change the outer diameter of the primary pulley with which the V-belt contacts, and the first actuator. And a second actuator that moves the movable sheave forward and backward, and the first actuator is driven by electric power. A second actuator that is driven by a centrifugal force associated with the rotation of the movable sheave. The movable sheave includes a cylindrical portion, and the second actuator of the outer peripheral surface of the cylindrical portion. A rolling bearing is arranged at a position that does not overlap in the axial direction. The first actuator moves the movable sheave forward and backward through the rolling bearing.

  In the belt-type continuously variable transmission according to one embodiment, the second actuator includes a plurality of centrifugal weights arranged around a rotation axis of the movable sheave and the centrifugal weight between the movable sheaves. A ramp plate that holds and guides the centrifugal weight to move radially outward by a centrifugal force accompanying the rotation of the movable sheave, the cylindrical portion penetrating the ramp plate, and the cylindrical portion It is preferable that the rolling bearing is fitted and fixed to a portion protruding from the lamp plate.

In the belt-type continuously variable transmission according to one embodiment, the cylindrical portion extends to the fixed sheave side, and the rolling bearing is disposed at a position that does not overlap the fixed sheave in the axial direction. Is preferred.
In the belt type continuously variable transmission according to one embodiment, it is preferable that the fixed sheave is fitted to the cylindrical portion.

Further, the cylindrical portion is constituted by an arc cross-section divided body obtained by dividing a cylindrical shape in the circumferential direction, and these arc cross-section divided bodies are respectively inserted into a plurality of divided body insertion holes formed in the fixed sheave. The rolling bearing is arranged on the outer periphery of the divided body.
Furthermore, in the belt-type continuously variable transmission according to one embodiment, it is preferable that the rolling bearing is disposed between the fixed sheave and the movable sheave.

  According to the belt-type continuously variable transmission according to the present invention, since the movable sheave is provided with a cylindrical portion, and the rolling bearing is disposed at a position that does not overlap the second actuator in the axial direction on the outer peripheral surface of the cylindrical portion. The bearing can be reduced in diameter. As a result, it is possible to obtain a belt type continuously variable transmission that allows high rotation at low cost.

1 is a skeleton diagram showing a belt-type continuously variable transmission according to a first embodiment of the present invention. It is a figure which shows the specific structure of the primary pulley of 1st Embodiment. It is a figure which shows the structure of the lamp plate currently used in 1st Embodiment. It is a skeleton figure which shows the belt-type continuously variable transmission of 2nd Embodiment which concerns on this invention. It is a figure which shows the specific structure of the primary pulley of 2nd Embodiment. It is a skeleton figure which shows the belt-type continuously variable transmission of 3rd Embodiment which concerns on this invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings.
(First embodiment)
1 to 3 show a belt type continuously variable transmission 10 according to a first embodiment.
FIG. 1 is a skeleton diagram showing a belt type continuously variable transmission 10 according to the present embodiment. A primary pulley 200, a secondary pulley 250, a V belt 211, a first actuator 100, and a second actuator 500 are illustrated. It has.

The primary pulley 200 includes a fixed sheave 203 fixed to the primary pulley shaft 201 and a movable sheave 207 facing the fixed sheave 203 so as to be movable along the axial direction of the primary pulley shaft 201.
The primary pulley shaft 201 is rotatably supported by the engine case 12 via a rolling bearing 202 so that a rotational driving force is transmitted from the crankshaft 14 of the engine 13.

As shown in FIG. 2, the fixed sheave 203 has a right end surface formed as a conical surface 203a and a press-fitting hole 203b formed at the axial center position. The reduced diameter portion 201a of the primary pulley shaft 201 is press-fitted into the press-fitting hole 203b.
A shaft insertion hole 502a and a cylindrical sleeve 204, which will be described later, are externally inserted in the reduced diameter portion 201a of the primary pulley shaft 201 on the right side of the fixed sheave 203. The nut 205 is screwed into a male thread formed on the outer periphery of the left end of the reduced diameter portion 201a, so that the axial movement of the fixed sheave 203, the sleeve 204, and the lamp plate 502 is restricted, and the fixed sheave 203 is the primary sheave 203. The pulley shaft 201 rotates together with the pulley shaft 201.

A movable sheave 207 is fitted to the outer periphery of the sleeve 204 so as to be movable in the axial direction and integrally rotate.
In the movable sheave 207, the left end of the central cylindrical portion 207a extends radially outward in the shape of a flange, and the left end surface thereof is a conical surface 203a of the fixed sheave 203 and a conical surface 207b having a mirror image shape. The conical surface 203a of the fixed sheave 203 and the conical surface 207b of the movable sheave 207 are separated in the axial direction as going outward in the radial direction.

An outer cylindrical portion 207c is formed on the outer peripheral side of the movable sheave 207 with respect to the central cylindrical portion 207a, and a second later described between the inner peripheral surface of the outer cylindrical portion 207c and the outer peripheral surface of the central cylindrical portion 207a. The actuator 500 is arranged.
Here, a plurality of arc-shaped cross sections 210 extending in the axial direction by dividing the cylindrical shape at equal intervals in the circumferential direction at the axial end located on the opposite side to the conical surface 207b of the central cylindrical portion 207a. Is formed.
An inner ring of the rolling bearing 208 is press-fitted into the outer periphery of the plurality of arcuate sectional divided bodies 210, and an outer ring of the rolling bearing 208 is fitted into the bearing holder 209.

A trapezoidal V-belt 211 is disposed between the fixed sheave 203 and the movable sheave 207.
The primary pulley 200 configured as described above has a pulley groove between the conical surface 203a of the fixed sheave 203 and the conical surface 207b of the movable sheave 207. The pulley groove is extended by the primary pulley 200 and a secondary pulley 250 described later. One end side (in this embodiment, the upper end side) of the V belt 211 stretched in a circular shape is wound from the outer peripheral side. Further, the other end side (the lower end side in FIG. 1) of the V-belt 211 is wound around a secondary pulley 250 on the driven side.

As shown in FIG. 1, the secondary pulley 250 includes a secondary pulley shaft 251 coupled to a drive wheel axle 34 via a speed reducer 32, fixed sheaves 253 disposed on the outer peripheral side of the secondary pulley shaft 251, and A movable sheave 257 and a centrifugal clutch mechanism 252 attached to the outer side in the axial direction of the movable sheave 257 are provided.
The fixed sheave 253 is disposed on the base end side (right side in FIG. 1) along the axial direction with respect to the movable sheave 257, and rotates integrally with the secondary pulley shaft 251. The fixed sheave 253 has a conical surface 253a whose end surface on the inner side in the axial direction has the same shape as the conical surface 203a of the fixed sheave 203 of the primary pulley 200.

  The movable sheave 257 includes a sheave body portion 255 and a rolling bearing 256 that is coaxially attached to the inner peripheral surface of the sheave body portion 255. The rolling bearing 256 has an outer ring fixed to the inner peripheral surface of the sheave body 255 and an inner ring splined to a spline portion (not shown) provided on a part of the secondary pulley shaft 251. The sheave body portion 255 is fitted on the outer peripheral side of the secondary pulley shaft 251 so as to be slidable in the axial direction. Thereby, the movable sheave 257 can be rotated relative to the secondary pulley shaft 251 and can move along the axial direction.

  The centrifugal clutch mechanism 252 includes an inner ring disk disposed on the outer peripheral side of the secondary pulley shaft 251, an outer ring disk disposed on the outer peripheral side of the inner ring disk, and a friction member disposed between the inner ring disk and the outer ring disk. Yes. The inner ring disc is rotatable relative to the secondary pulley shaft 251 and is fixed so as to rotate integrally with the sheave body portion 255. The outer ring disc is rotatable relative to the inner ring disc and is fixed so as to rotate integrally with the secondary pulley shaft 251.

The centrifugal clutch mechanism 252 is configured as a starting clutch, and when the inner ring disk starts to rotate, the friction member moves to the outer peripheral side by centrifugal force, and connects the inner ring disk to the outer ring disk so that torque can be transmitted. As a result, the rotation of the inner ring disc is transmitted to the secondary pulley shaft 251 via the friction member and the outer ring disc, and the secondary pulley shaft 251 starts to rotate slightly after the inner ring disc.
In the secondary pulley 250, a space between the conical surface 253a of the fixed sheave 253 and the conical surface 257a of the movable sheave 257 is a pulley groove, and this pulley groove has the other end side of the V belt 211 (in this embodiment, The lower end side is wound from the outer peripheral side.

  As shown in FIG. 1, the first actuator 100 includes an electric motor 100a that is an actuator drive source, and an output shaft 100b that serves as an output unit that is operated by the power of the electric motor 100a. The output shaft 100b is directly or indirectly connected to the end face of the bearing holder 209 of the primary pulley 200, and moves the movable sheave 207 in the axial direction via the bearing holder 209 and the rolling bearing 208. The position of the first actuator 100 is not particularly limited, and may be disposed inside the engine case 12 or may be disposed outside the engine case 12.

The second actuator 500 includes a plurality of centrifugal weights 501 and a ramp plate 502 as shown in FIG.
The plurality of centrifugal weights 501 are arranged around the rotating shaft (the reduced diameter portion 201a) of the movable sheave 207 at a predetermined interval, and are provided between the central cylindrical portion 207a and the outer cylindrical portion 207c of the movable sheave 207. It is in contact with the slope 207d.

The ramp plate 502 is a member that holds the centrifugal weight 501 between the movable sheave 207 and moves the centrifugal weight 501 outward in the radial direction by being guided by the guide inclined surface 207d by the centrifugal force accompanying the rotation of the movable sheave 207. .
As shown in FIG. 3, the ramp plate 502 is a substantially disk-shaped member, and a shaft insertion hole 502 a through which the reduced diameter portion 201 a of the primary pulley shaft 201 is inserted is provided at the center thereof. On the outer peripheral side of the insertion hole 502a, a plurality of arc-shaped divided body insertion holes 502b through which the plurality of arc-shaped cross-section divided bodies 210 constituting the central cylindrical portion 207a of the movable sheave 207 are inserted are formed.

  Then, the plurality of arcuate cross-sectional divided bodies 210 of the central cylindrical portion 207a are inserted into the plurality of divided body insertion holes 502b of the lamp plate 502, respectively, so that they are axially outer than the second actuator 500 (FIGS. 1 and 2). The central cylinder part 207a can be protruded to the right side of FIG. For this reason, the rolling bearing 208 and the bearing holder 209 can be arrange | positioned in the part which the center cylinder part 207a protruded. As a result, the movable sheave 207 can be moved in the axial direction by the first actuator 100 via these.

  With the above configuration, it is not necessary to provide the rolling bearing 208 that transmits the power of the first actuator 100 to the movable sheave 207 on the outer diameter side of the movable sheave 207. For this reason, the dimension of the rolling bearing 208 can be made small, and the whole apparatus can be reduced in size. Further, by reducing the size of the rolling bearing 208, it is possible to reduce the cost of the rolling bearing 208 and increase the allowable rotational speed. As a result, the belt-type continuously variable transmission 10 can be made compact and high reliability can be obtained without reducing the power for moving the movable sheave.

(Second Embodiment)
Next, FIGS. 4 and 5 show a belt type continuously variable transmission 20 according to a second embodiment of the present invention. In addition, about the structure equivalent to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.
In the present embodiment, the movable sheave 207 of the primary pulley 200 is formed with a plurality of circular cross-section divided bodies 212 that protrude from the central cylindrical portion 207a to the fixed sheave 203 side (left side in FIG. 5). The plurality of arc-shaped cross-sections 212 are portions that are formed by dividing a cylindrical shape at equal intervals in the circumferential direction and extend in the axial direction.

The fixed sheave 203 is formed with a plurality of arc-shaped divided body insertion holes 507 through which the plurality of arc-shaped cross-section divided bodies 212 of the movable sheave 207 are inserted, and the plurality of arc-shaped divided body insertion holes 507 are respectively inserted into the plurality of arc-shaped divided body insertion holes 507. The inner ring of the rolling bearing 508 is press-fitted into the outer periphery of the plurality of circular section sections 212 inserted, and the outer ring of the rolling bearing 208 is fitted to the bearing holder 509.
Then, the power of the first actuator 100 is transmitted to the movable sheave 207 via the rolling bearing 508 and the bearing holder 509.

  Also in this embodiment, the plurality of arc-shaped cross-section divided bodies 212 of the movable sheave 207 are respectively inserted into the plurality of divided body insertion holes 507 of the fixed sheave 203 so that the back side of the fixed sheave 203 (the left side in FIGS. 4 and 5). ) Can project the arc-shaped cross section 212. For this reason, the rolling bearing 508 and the bearing holder 509 can be arranged on the protruding portion of the arcuate cross section 212. As a result, the movable sheave 207 can be moved in the axial direction by the first actuator 100 via these.

  Therefore, also in this embodiment, it is not necessary to provide the rolling bearing 508 for transmitting the power of the first actuator 100 to the movable sheave 207 on the outer diameter side of the movable sheave 207, and the size of the rolling bearing 508 can be reduced. The entire device can be downsized. In addition, by reducing the size of the rolling bearing 508, the cost of the rolling bearing 508 can be reduced and the allowable number of rotations can be increased. As a result, the belt-type continuously variable transmission 20 can be made compact and high reliability can be obtained without reducing the power for moving the movable sheave 207.

(Third embodiment)
Next, FIG. 6 shows a belt type continuously variable transmission 21 according to a third embodiment of the present invention.
In this embodiment, a cylindrical portion 207e is formed on the movable sheave 207 of the primary pulley 200 so as to extend on the same axis line of the central cylindrical portion 207a to a position where it does not overlap with the fixed sheave 203. Further, the fixed sheave 203 is not fitted with the cylindrical portion 207e, but is fitted with the primary pulley shaft 201 as in the first embodiment.

Further, the inner ring of the rolling bearing 508 is press-fitted into the outer periphery of the cylindrical portion 207 e, and the outer ring of the rolling bearing 208 is fitted into the bearing holder 509.
Then, the power of the first actuator 100 is transmitted to the movable sheave 207 via the rolling bearing 508 and the bearing holder 509.

  In the present embodiment, similarly to the first and second embodiments, it is not necessary to provide the rolling bearing 508 for transmitting the power of the first actuator 100 to the movable sheave 207 on the outer diameter side of the movable sheave 207, and the rolling bearing. The size of 508 can be reduced, and the entire apparatus can be reduced in size. In addition, by reducing the size of the rolling bearing 508, the cost of the rolling bearing 508 can be reduced and the allowable number of rotations can be increased. As a result, the belt-type continuously variable transmission 21 can be made compact and high reliability can be obtained without reducing the power for moving the movable sheave 207.

  DESCRIPTION OF SYMBOLS 10, 20, 21 ... Belt type continuously variable transmission, 12 ... Engine case, 13 ... Engine, 14 ... Crankshaft, 32 ... Reduction gear, 34 ... Axle, 100 ... First actuator, 100a ... Electric motor, 100b ... Output shaft 200 ... Primary pulley 201 ... Primary pulley shaft 201a ... Reduced diameter portion 202 ... Rolling bearing 203 ... Fixed sheave 203a ... Conical surface 203b ... Press-fitting hole 204 ... Sleeve 205 ... Nut 207 ... Movable sheave, 207a ... center tube portion, 207b ... conical surface, 207c ... outer tube portion, 207d ... guide slope, 207e ... cylindrical portion, 208 ... rolling bearing, 209 ... bearing holder, 210, 212 ... circular sectional section (cylindrical) Part), 211 ... V belt, 250 ... secondary pulley, 251 ... secondary pulley shaft, 252 ... centrifugal clutch 253 ... fixed sheave, 253a ... conical surface, 255 ... sheave body, 256 ... rolling bearing, 257 ... movable sheave, 257a ... conical surface, 500 ... second actuator, 501 ... centrifugal weight, 502 ... lamp plate, 502a ... Shaft insertion hole, 507 ... Divided body insertion hole, 508 ... Rolling bearing, 509 ... Bearing holder

Claims (6)

A primary sheave having a fixed sheave fixed to a pulley shaft and a movable sheave supported by the pulley shaft so as to be movable in an axial direction, and having a pulley groove formed between the fixed sheave and the movable sheave; A pulley and a secondary pulley;
An endless V-belt wound between pulley grooves of the primary pulley and the secondary pulley;
A first actuator that causes the movable sheave of the primary pulley to advance and retreat in the axial direction via a link mechanism to change the outer diameter of the primary pulley that the V belt contacts;
A second actuator for advancing and retracting the movable sheave in cooperation with the first actuator;
The first actuator is an actuator driven by electric power;
The second actuator is an actuator driven by a centrifugal force accompanying the rotation of the movable sheave,
The movable sheave has a cylindrical portion, and a rolling bearing is disposed at a position in the outer peripheral surface of the cylindrical portion that does not overlap with the second actuator in the axial direction.
The belt-type continuously variable transmission according to claim 1, wherein the first actuator moves the movable sheave forward and backward through the rolling bearing. The second actuator holds a plurality of centrifugal weights arranged around the rotation axis of the movable sheave and the centrifugal weight between the movable sheaves, and the centrifugal weight causes a centrifugal force accompanying the rotation of the movable sheave. And a lamp plate that guides moving outward in the radial direction by
The cylindrical portion passes through the lamp plate,
The belt type continuously variable transmission according to claim 1, wherein the rolling bearing is fitted and fixed to a portion of the cylindrical portion protruding from the ramp plate.   2. The belt-type continuously variable transmission according to claim 1, wherein the cylindrical portion extends to the fixed sheave side, and the rolling bearing is disposed at a position that does not overlap the fixed sheave in the axial direction. .   The belt-type continuously variable transmission according to claim 3, wherein the fixed sheave is fitted to the cylindrical portion. The cylindrical portion is composed of an arc cross-section divided into a cylindrical shape in the circumferential direction,
5. These arc-shaped cross-sections are respectively inserted into a plurality of split-body insertion holes formed in the fixed sheave, and the rolling bearings are arranged on the outer periphery of these arc-section cross-sections. The belt type continuously variable transmission described in 1.   The belt type continuously variable transmission according to claim 3 or 4, wherein the rolling bearing is disposed between the fixed sheave and the movable sheave.

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