JP2015178867A - Pulley mechanism, transmission including pulley mechanism, and vehicle including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulley mechanism applied to a continuously variable transmission, capable of setting a thrust to have an appropriate magnitude.SOLUTION: A pulley mechanism comprises: a plunger 32; a fixed pulley 2; a movable pulley 3 between the plunger 32 and the fixed pulley 2; a groove 4 provided between the fixed pulley 2 and the movable pulley 3; a pressure reception chamber 33 provided between the movable pulley 3 and the plunger 32; and oil passages 11 and 12, the oil passages 11 and 12 supplying oil to the pressure reception chamber 33 if a width of the groove 4 is smaller than a predetermined value, and the pressure reception chamber being divided into a first chamber 331 and a second chamber 332 and the oil passages 11 and 12 supplying the oil to the first chamber 331 if the width of the groove 4 is equal to or larger than the predetermined value.

Description

  The present invention relates to a pulley mechanism including a movable pulley and a fixed pulley for clamping a power transmission member by hydraulic pressure, a transmission having the pulley mechanism, and a vehicle including the transmission.

  A continuously variable transmission for a vehicle includes two pulley mechanisms connected to respective rotary shafts, and belts or chains (hereinafter collectively referred to as “belts”) wound around these pulley mechanisms. Those are known (for example, see Patent Document 1).

  In such a continuously variable transmission, power is transmitted from one pulley mechanism to the other pulley mechanism via a belt which is a power transmission member.

  Both pulley mechanisms have V-shaped cross-sectional grooves, and by expanding and reducing the groove width of each groove, each pulley radius is changed, and the gear ratio is changed between the lowest and highest.

  FIG. 6 shows an example of the output side (secondary) pulley mechanism of the continuously variable transmission. As shown in FIG. 6, the pulley mechanism includes a fixed pulley 2 and a movable pulley 3 concentrically with the rotating shaft 1. ing.

  The fixed pulley 2 is fixed to the rotating shaft 1, the movable pulley 3 is movable in the axial direction and is integrally locked in the rotating direction, and the fixed pulley 2 and the movable pulley 3 rotate integrally with the rotating shaft 1.

  The opposing surfaces of the fixed pulley 2 and the movable pulley 3 form a groove 4 having a V-shaped cross section by both surfaces, and the belt 5 is clamped in the groove 4.

  The movable pulley 3 has a cylinder 31 extending toward the side opposite to the front side facing the fixed pulley 2 (hereinafter referred to as “back side”).

  The inner peripheral surface 31a of the cylinder 31 is a cylindrical surface parallel to the rotary shaft 1, and the inner diameter of the cylinder 31 is constant regardless of the axial position.

  A plunger 32 is fixed on the back side of the movable pulley 3 on the rotary shaft 1, and is surrounded by a back surface 30 b of the movable pulley 3, an inner peripheral surface 31 a of the cylinder 31, a front surface 32 a of the plunger 32, and the like, thereby forming a pressure receiving chamber 33. ing.

  A seal member 51 is provided on the outer peripheral portion 32 b of the plunger 32, and a sliding portion with the inner peripheral surface 31 a of the cylinder 31 is sealed (sealed).

  The pressure receiving chamber 33 is supplied with oil whose pressure (hereinafter referred to as “hydraulic pressure P”) is controlled by a hydraulic control system having an oil pump and a hydraulic control valve.

  The position of the movable pulley 3 relative to the rotating shaft 1 is changed according to the amount of oil in the pressure receiving chamber 33, the groove width of the groove 4 is expanded and reduced, and the gear ratio is changed.

  The hydraulic pressure P in the pressure receiving chamber 33 is applied to the back surface (surface orthogonal to the axial direction) 30b of the movable pulley 3 and acts as a force for clamping the belt 5 in the groove 4 (hereinafter referred to as “thrust force F”).

Thrust by the hydraulic pressure P (hydraulic thrust) F _p, as indicated by the following equation (1), axially projected area of the pressure receiving surface of the pressure P and the movable pulley 3 (hereinafter referred to as "pressure-receiving area A") according to the It will be.
F _p = P × A (1)

  However, the pulley mechanism shown in FIG. 6 is a secondary pulley mechanism, and is provided with a spring 35 that applies thrust F and fixes the gear ratio to low even when the vehicle cannot be supplied with hydraulic pressure P.

  The spring 35 is interposed between the back surface 30b of the movable pulley 3 and the front surface 32a of the plunger 32 in a compressed state, and always urges the movable pulley 3 toward the fixed pulley 2 side.

Therefore, the thrust F _sec of the secondary pulley mechanism is obtained by adding the _urging force F _spr to the hydraulic thrust F _p based on the oil pressure P _sec and the pressure receiving area A _sec of the pressure receiving chamber 33 of the secondary pulley mechanism as shown in the following equation (2). It becomes a thing.
F _sec = F _p + F _spr = P _sec × A _sec + F _spr (2)

Since the primary pulley mechanism on the input side is not provided with a spring, the thrust F _pri of the primary pulley mechanism is the hydraulic thrust F _p based on the hydraulic pressure P _pri and the pressure receiving area A _{pri as} shown in the following equation (3). It becomes only.
F _pri = F _p = P _pri × A _pri (3)

The gear ratio is determined according to the ratio of these thrusts (F _pri / F _sec , hereinafter referred to as “thrust ratio Z”) and the torque transmission state (torque ratio) of the vehicle drive or coast.

If the torque ratio is constant, the gear ratio is determined by the thrust ratio Z, to change gear ratio in response to this by changing the thrust ratio Z from one thrust ratio that holds the speed ratio (balance thrust ratio) Z _b.

JP 2005-3012 A

By the way, the hydraulic pressure P applied to the pulley mechanism from the hydraulic pressure supply system is set with a certain lower limit value (hereinafter referred to as “minimum pressure P _min ”) for the following reasons 1 and 2.

(Reason 1) If the oil pressure P is too low, the control response of the oil pressure P is lowered and the response of the shift is lowered. _Therefore , the control is performed in the range of the minimum pressure P _min or more to ensure the response of the shift.
(Reason 2) If the oil pressure P is too low, it is difficult to generate the oil pressure P stably by the oil pump, and the oil pressure P is generated stably.

For this reason, the lower limit value of the thrust F (hereinafter referred to as “minimum thrust force F _min ”) also has a magnitude corresponding to the minimum pressure P _min as shown in the following equation (4).
F _min = P _min × A (4)

If this minimum thrust F _min is larger than the minimum thrust required to transmit power by the belt (hereinafter referred to as “required thrust F _rq ”), the pulley mechanism will have an excessive thrust (hereinafter referred to as “excess thrust F F”). _o ") will work.

This excess thrust F _o is expressed by the following equation (5).
F _o = F _min −F _rq (5)

The required thrust F _rq is proportional to the torque to be transmitted (hereinafter referred to as “transmission torque T”).

For example, when the winding radius R in one pulley mechanism is small and the winding radius R in the other pulley mechanism is large, the transmission torque T ₁ in one pulley mechanism is larger than the transmission torque T ₂ in the other pulley mechanism. Get smaller.

At this time, required thrust F _rq in the pulley mechanism is small, required thrust F _rq in other pulley mechanism increases.

However, in the continuously variable transmission, since the speed ratio is changed according to the thrust ratio Z, when the minimum thrust _Fmin is larger than the required thrust _Frq , an excess thrust _Fo is generated in each pulley mechanism.

In particular, in the pulley mechanism, when the winding radius R is small and the transmission torque T is small, in other words, when the groove width is large due to the separation between the fixed pulley and the movable pulley, the necessary thrust F _rq is small. There is a risk that the excessive thrust F _o will increase.

As shown in FIG. 6, in the secondary pulley mechanism provided with the spring 35 for applying the thrust F _spr , when the winding radius R is decreased, the spring 35 is also compressed and the urging force is increased, and the thrust F _spr is also increased. The excessive thrust F _o becomes larger and larger.

  One of the objects of the present invention has been invented in view of such a problem. A pulley mechanism, a continuously variable transmission having the pulley mechanism, and a continuously variable transmission capable of setting the thrust to an appropriate magnitude are disclosed. The present invention provides a vehicle including a continuously variable transmission.

  Note that the present invention is not limited to this purpose, and other effects of the present invention can also be achieved by the functions and effects derived from the respective configurations shown in the embodiments for carrying out the invention which will be described later. Can be positioned as

  (1) In order to achieve the above object, the pulley mechanism of the present invention has a plunger, a fixed pulley, a movable pulley between the plunger and the fixed pulley, A groove is provided between the movable pulley, a pressure receiving chamber is provided between the movable pulley and the plunger, an oil passage is provided, and when the width of the groove is less than a predetermined value, the oil passage is When oil is supplied to the pressure receiving chamber, and the width of the groove is equal to or greater than the predetermined value, the pressure receiving chamber is divided into a first chamber and a second chamber, and the oil passage supplies oil to the first chamber. It is characterized by supplying.

  (2) Another pulley mechanism according to the present invention includes a plunger, a fixed pulley, a movable pulley between the plunger and the fixed pulley, and between the fixed pulley and the movable pulley. A biasing means for applying a thrust to the movable pulley, a pressure receiving chamber between the movable pulley and the plunger, an oil passage, and when the thrust is less than a predetermined value The oil passage supplies oil to the pressure receiving chamber, and when the thrust is equal to or greater than the predetermined value, the pressure receiving chamber is divided into a first chamber and a second chamber, and the oil passage is the first passage. It is characterized by supplying oil to the chamber.

  (3) The movable pulley has a cylindrical portion, the movable pulley has a first cylindrical projection portion inward of the cylindrical portion, and the plunger is an inner portion of the cylindrical portion. The plunger has an outer peripheral portion that is in sliding contact with the peripheral surface, and the plunger has a second cylindrical protrusion portion inward of the outer peripheral portion, and the first cylindrical protrusion portion and the second cylindrical protrusion. It is preferable that the pressure receiving chamber is divided into the first chamber and the second chamber when the portion is in proximity.

  (4) In this case, it is preferable that the said movable pulley has a recessed part which can accommodate the said 2nd cylindrical projection part.

  (5) It is preferable to have a centrifugal cancel chamber and a first one-way oil passage through which oil can flow from the centrifugal cancel chamber toward the second chamber.

  (6) It is preferable to have a second one-way oil passage through which oil can flow from the second chamber toward the first receiving chamber.

  (7) A continuously variable transmission according to the present invention includes the pulley mechanism according to any one of (1) to (6).

  (8) A vehicle according to the present invention includes the continuously variable transmission according to (7) above.

  According to the present invention, when the groove width of the groove is greater than or equal to a predetermined value or when the thrust is greater than or equal to a predetermined value, the pressure receiving chamber is divided into the first chamber and the second chamber. Even if oil is supplied to the chamber, no oil is supplied to the second chamber.

  That is, the area of the pressure receiving surface (pressure receiving area) of the movable pulley that is received from the oil in the pressure receiving chamber is reduced, and the thrust by the hydraulic pressure is reduced even when the pulley minimum pressure condition is set.

  Therefore, it is possible to prevent the total thrust from becoming larger than necessary.

  When a continuously variable transmission having such a pulley mechanism is applied to a vehicle, the fuel consumption of the vehicle can be improved.

It is a longitudinal cross-sectional view which shows the half part of the pulley mechanism concerning 1st Embodiment, (a) is a general view, (b) is the elements on larger scale. It is a longitudinal cross-sectional view explaining operation | movement of the pulley mechanism concerning 1st Embodiment, (a) shows the state (intermediate gear ratio state) in which the groove width is expanding, (b) expanded the groove width to the maximum. Indicates the state (highest state). It is a figure which shows the characteristic of the thrust ratio of the continuously variable transmission ratio concerning each embodiment. It is a longitudinal cross-sectional view which shows the half part of the pulley mechanism concerning 2nd Embodiment, (a) is a general view, (b) is the elements on larger scale. It is a longitudinal cross-sectional view which shows the half part of the pulley mechanism concerning 3rd Embodiment, (a) is a general view, (b) is the elements on larger scale. It is a longitudinal cross-sectional view which shows the half part of the pulley mechanism concerning background art.

  Hereinafter, an embodiment according to a pulley mechanism of the present invention will be described with reference to the drawings.

  In this embodiment, a description will be given of a pulley mechanism used in a continuously variable transmission.

  The continuously variable transmission is mounted on a vehicle such as an automobile or a motorcycle.

  A continuously variable transmission for a vehicle includes a pulley mechanism connected to each rotation shaft of a primary shaft and a secondary shaft, and a power transmission member such as a belt or a chain wound around these pulley mechanisms.

  In the continuously variable transmission, power is transmitted in accordance with a driving state such as driving and coasting of the vehicle.

  For example, during driving of the vehicle, power is transmitted from one pulley mechanism (primary pulley mechanism) to the other pulley mechanism (secondary pulley mechanism) via a power transmission member.

  Further, during coasting of the vehicle, power is transmitted from the other pulley mechanism (secondary pulley mechanism) to one pulley mechanism (primary pulley mechanism) via the power transmission member.

  In the following description, an example applied to a belt type continuously variable transmission using a belt as a power transmission member will be described.

  The two pulley mechanisms are basically configured in the same manner although some of them are different.

  In the present embodiment, description will be given focusing on the secondary pulley mechanism on the output side during driving.

  In the present embodiment, a direction along the rotation axis is an axial direction, and a direction orthogonal to the axial direction is a radial direction.

  In the radial direction, the side closer to the rotation axis is the inner side, and the side far from the rotation axis is the outer side.

  In the following description, components having the same configuration as the pulley mechanism of the continuously variable transmission according to the background art described with reference to FIG.

[1. First Embodiment]
[1-1. Constitution〕
[1-1-1. Basic configuration)
Hereinafter, the basic configuration of the pulley mechanism according to the first embodiment will be described with reference to FIG.

  As shown in FIG. 1A, the pulley mechanism has a fixed pulley 2 and a movable pulley 3, and power is transmitted between the rotating shaft 1 and the belt 5 via the fixed pulley 2 and the movable pulley 3. To communicate.

  The fixed pulley 2 is fixed to the rotating shaft 1, the movable pulley 3 is movable in the axial direction and is integrally locked in the rotating direction, and the fixed pulley 2 and the movable pulley 3 rotate integrally with the rotating shaft 1. .

  The fixed pulley 2 and the movable pulley 3 have disk-like pulley main body portions 20 and 30.

  Opposing surfaces 20a and 30a of the pulley main body portions 20 and 30 facing each other are inclined so as to be separated from each other toward the outside, and form a V-shaped cross-sectional groove (V-shaped groove) 4. .

  In this embodiment, the groove 4 is a V-shaped groove having a general V-shaped cross-sectional shape, but the shape of the groove 4 is not limited to this.

  The belt 5 is clamped in the groove 4 by the facing surfaces 20 a and 30 a of the fixed pulley 2 and the movable pulley 3.

  The facing surfaces 20a and 30a of the fixed pulley 2 and the movable pulley 3 that clamp the belt 5 are also referred to as sheave surfaces, and the sheave angle α that is each inclination angle is set to the same angle in the reverse direction.

  The groove width of the groove 4 expands and contracts according to the position of the movable pulley 3 in the axial direction, and the radius at which the belt 5 winds around the pulley mechanism, that is, the pulley radius is changed by expanding and contracting the groove width.

  The groove width of the groove 4, that is, the axial position of the movable pulley 3 is changed or held by applying a thrust F that thrusts the movable pulley 3 toward the fixed pulley 2.

  However, since the fixed pulley 2 and the movable pulley 3 receive the thrust F of another pulley mechanism (primary pulley mechanism) via the belt 5, the groove width is determined by the thrust balance of these pulley mechanisms.

  This pulley mechanism is devised so that the thrust F applied to the movable pulley 3 does not become excessive, and hereinafter, the configuration of each part and the configuration peculiar to this mechanism will be described by focusing on the application of the thrust F.

[1-1-2. (Configuration of each part)
Power is input to the rotary shaft 1 from the belt 5 when the vehicle is driving, and power is output to the belt 5 when the vehicle is coasting.

  That is, during driving, the vehicle travels by transmitting the driving force of a power source (not shown) such as an engine or an electric motor to driving wheels (not shown).

  During this driving, the driving force of the power source is input to another pulley mechanism (primary pulley mechanism) and input to the pulley mechanism (secondary pulley mechanism) via the belt 5.

  During coast running, the power generated by the rotation of the drive wheels is transmitted to the power source side to run.

  During this coasting, the rotational force of the drive wheels is input to this pulley mechanism (secondary pulley mechanism) and input to another pulley mechanism (primary pulley mechanism) via the belt 5.

  The rotating shaft 1 is rotatably supported by a transmission case (not shown) by bearings 6a and 6b.

  A gear 7 is fixed on one end side of the rotating shaft 1 and connected to the drive wheel side through another gear (not shown) that meshes with the gear 7.

  The drive wheel side is equipped with an input shaft of a speed change mechanism such as a speed reducer or a sub-transmission.

  The fixed pulley 2 is formed integrally with the rotating shaft 1 or is fixed to the rotating shaft 1 integrally in the rotational direction and the axial direction even if it is a separate body.

  The pulley main body 30 of the movable pulley 3 has a back surface 30b facing the side opposite to the sheave surface 30a (hereinafter referred to as the back side).

  A cylinder (tubular portion) 31 </ b> A and a hollow shaft portion (inner tube portion) 31 </ b> B are extended on the back side of the pulley body 30 of the movable pulley 3.

  The movable pulley 3 is equipped with a hollow shaft 31B coupled to the outer periphery of the rotary shaft 1 so as to be slidable in the axial direction by serration coupling or the like.

  A plunger 32 is provided inside a cylinder (tubular portion) 31 </ b> A on the back side of the pulley body 30.

  The plunger 32 is formed in a shape in which a cylindrical portion along the rotation axis 1 and a flange-like portion having a surface facing the back surface 30b of the pulley main body 30 are combined.

  The innermost cylindrical portion 32 c of the plunger 32 is integrally coupled to the rotary shaft 1 in the rotational direction and the axial direction.

  The plunger 32 extends outward from the cylindrical portion 32 c through the flange portion and the cylindrical portion, and the outermost outer peripheral portion 32 b is in sliding contact with the inner peripheral surface 31 a of the cylinder 31.

  A seal member 51 is provided on the outer peripheral portion 32 b of the plunger 32, and is in close contact with and in sliding contact with the inner peripheral surface 31 a of the cylinder 31.

  A pressure receiving chamber 33 is formed between the movable pulley 3 and the plunger 32.

  The pressure receiving chamber 33 includes a back surface 30b of the pulley main body 30, an outer peripheral surface 31b of the hollow shaft 31B, an outer peripheral surface 1a of the rotary shaft 1, an inner surface 32a of the plunger 32, and an inner peripheral surface 31a of the cylinder 31. It is formed to be surrounded.

  The inner surface 32a of the plunger 32 includes a surface facing the back surface 30b of the pulley main body 30 and a surface facing the outer peripheral surface 31b of the hollow shaft portion 31B and the outer peripheral surface 1a of the rotary shaft 1.

  A spring 35 is interposed in the pressure receiving chamber 33 between the back surface 30b of the pulley main body 30 and the inner surface 32a of the plunger 32 facing the pulley 30 in a compressed state.

  The pulley mechanism according to the embodiment is a secondary pulley mechanism, and the spring 35 is provided to apply a thrust F even when the vehicle is stopped when the hydraulic pressure P cannot be supplied to the pressure receiving chamber 33.

  Further, a cancel plate 40 for forming a centrifugal cancel chamber 41 is provided on the opposite side (back side) of the movable pulley 3 of the plunger 32.

  The cancel plate 40 is formed in a shape in which a cylindrical portion and a bowl-shaped portion are combined so as to substantially follow the shape of the plunger 32.

  The outer peripheral portion of the cancel plate 40 is liquid-tightly coupled to the protruding end portion of the cylinder 31 of the movable pulley 3 and moves in the axial direction integrally with the movable pulley 3.

  The centrifugal cancel chamber 41 is formed by being surrounded by an inner peripheral surface 31a of the cylinder 31, a back surface 32d of the plunger 32, and a surface (inner surface) 40a of the cancel plate 40 facing the plunger 32.

  The rotating shaft 1 is provided with an oil passage 11 along the axial center line, and an oil passage 12 that communicates the oil passage 11 with the pressure receiving chamber 33 outside the outer peripheral surface of the rotating shaft 1. .

  Oil discharged from an oil pump (not shown) is pressure-controlled by a hydraulic control valve (not shown) or the like and supplied through the oil passages 11 and 12 to the pressure receiving chamber 33.

  The pressure in the pressure receiving chamber 33 acts in the axial direction on the back surface 30 b of the pulley body 30 that is the pressure receiving surface, and gives a thrust F to the movable pulley 3.

  Further, an intake / exhaust port 41a for sucking and discharging oil in the centrifugal cancel chamber 41 is provided between the cancel plate 40 and the rotary shaft 1 on the axial center side, and the centrifugal cancel chamber 41 is always filled with oil corresponding to atmospheric pressure. It is.

  As shown in FIG. 2, the pulley mechanism is provided with pressure receiving chamber dividing means for dividing the pressure receiving chamber 33 into a first chamber 331 and a second chamber 332 under predetermined conditions in addition to such a configuration. There is a feature in the point.

[1-1-3. (Configuration of pressure receiving chamber classification means)
Here, the pressure receiving chamber dividing means of this embodiment will be described.

  As shown in FIGS. 1 (a) and 1 (b), a cylinder protruding toward the back surface 30b of the pulley main body 30 is formed on the flange-like portion closest to the movable pulley 3 inside the outer peripheral portion 32b of the plunger 32. A protruding portion (second cylindrical protruding portion) 321 is formed.

  On the back surface 30 b inside the cylinder 31 of the pulley main body 30, a recess 312 that can accommodate the cylindrical protrusion 321 is formed facing the cylindrical protrusion 321 of the plunger 32.

  Further, a cylindrical projection (first cylindrical projection) 311 that protrudes toward the flange-shaped portion of the plunger 32 is formed inside the concave portion 312 of the back surface 30b inside the cylinder 31.

  The outer peripheral surface 311 a of the cylindrical projection 311 of the movable pulley 3 is formed with a smaller diameter than the inner peripheral surface of the cylindrical projection 321 of the plunger 32.

  An annular groove is formed on the inner peripheral surface of the cylindrical projection 321 of the plunger 32, and an annular seal member 52 is provided inside the annular groove with the seal surface protruding inward.

  When the movable pulley 3 moves to widen the groove width of the groove 4, as shown in FIG. 2, the movable pulley 3 and the plunger 32 approach each other, and the cylindrical protrusion 321 of the plunger 32 is accommodated in the recess 312. The inner peripheral surface of the cylindrical protrusion 321 faces the outer peripheral surface 311 a of the cylindrical protrusion 311 of the movable pulley 3.

  At this time, as shown in FIG. 2A, the seal member 52 of the cylindrical protrusion 321 of the plunger 32 is in close contact with the outer peripheral surface 311 a of the cylindrical protrusion 311 and is in sliding contact.

  By this sliding contact, the pressure receiving chamber 33 is divided into an inner first chamber 331 and an outer second chamber 332.

  The suction and discharge of oil in the pressure receiving chamber 33 is performed through the oil passage 12 that opens to a location partitioned by the first chamber 331 inside the pressure receiving chamber 33.

  Therefore, when the pressure receiving chamber 33 is divided into the first chamber 331 and the second chamber 332, the hydraulic pressure does not act on the second chamber 332 unlike the first chamber 331.

  As a result, the pressure receiving surface is only the portion constituting the first chamber 331 in the back surface 30b of the pulley main body 30, and the pressure receiving surface is reduced.

  Further, when the movable pulley 3 moves so as to narrow the groove width of the groove 4, the movable pulley 3 and the plunger 32 are separated from each other, and the seal member 52 is separated from the outer peripheral surface 311a.

  By this separation, the first chamber 331 and the second chamber 332 communicate with each other and are formed in one pressure receiving chamber 33.

  A one-way oil passage through which oil can flow from the centrifugal cancel chamber 41 toward the second chamber 332 is formed in a wall portion (here, in the vicinity of the outer peripheral portion 32 b) that forms the second chamber 332 of the plunger 32. (First unidirectional oil passage) 61 is provided.

  The one-way oil passage 61 is for allowing the oil in the centrifugal cancel chamber 41 to flow into the second chamber 332 when the movable pulley 3 moves so as to narrow the groove width of the groove 4.

  Further, a one-way oil passage (second one passage) through which oil can be circulated from the second chamber 332 toward the first chamber 331 is formed in a wall section that divides the second chamber 332 and the first chamber 331. Direction oil passage) 62 is provided.

  When the groove width of the groove 4 is further expanded as shown in FIG. 2B in a state where the first chamber 331 and the second chamber 332 are separated, the one-way oil passage 62 is the second one. This is for discharging the oil in the chamber 332 to the first chamber 331.

  Note that check balls (check valves) 61a and 62a are employed in the one-way oil passages 61 and 62 of the present embodiment.

[1-2. Action and effect)
Since the pulley mechanism according to the first embodiment of the present invention is configured as described above, in the continuously variable transmission and the vehicle to which the pulley mechanism and the pulley mechanism are applied, the following operations and effects are obtained. be able to.

Hydraulic pressure P in the pressure receiving chamber 33 acts on the rear (pressure receiving surface) 30b of the pulley main body 30, thrust by the hydraulic pressure P (hydraulic thrust) F _p is, as shown in the following equation (1), a hydraulic P The pressure is applied in accordance with the projected area in the axial direction of the pressure receiving surface of the movable pulley 3 (hereinafter referred to as “pressure receiving area A”).
F _p = P × A (1)

Further, this pulley mechanism is applied to the secondary pulley, and since the _urging force F _spr of the spring 35 between the back surface 30b of the movable pulley 3 and the front surface 32a of the plunger 32 is added to the thrust F, the following equation (2) is _satisfied. As shown.
F _sec = F _p + F _spr = P _sec × A _sec + F _spr (2)

  Here, the pressure receiving surface is formed on the back surface 30b of the pulley main body 30, and the pressure receiving surface changes depending on whether the pressure receiving chamber 33 is divided by the pressure receiving chamber dividing means.

  That is, when the movable pulley 3 moves so as to widen the groove width of the groove 4 and the movable pulley 3 and the plunger 32 approach each other, the seal member 52 of the cylindrical protrusion 321 of the plunger 32 moves to the outer peripheral surface of the cylindrical protrusion 311. 311a is in close contact with and in sliding contact.

  By this sliding contact, the pressure receiving chamber 33 is divided into an inner first chamber 331 and an outer second chamber 332.

  Although the controlled hydraulic pressure acts in the first chamber 331, the controlled hydraulic pressure does not act on the second chamber 332.

  As a result, the pressure receiving surface is only the portion constituting the first chamber 331 in the back surface 30b of the pulley main body 30, and the pressure receiving area A is reduced.

  On the other hand, when the movable pulley 3 moves so as to narrow the groove width of the groove 4, the movable pulley 3 and the plunger 32 are separated from each other, and the seal member 52 is separated from the outer peripheral surface 311a, the first chamber 331 and the second chamber 331 are separated. The chamber 332 communicates with the chamber 332 and is formed in one pressure receiving chamber 33.

  As a result, the pressure receiving surface becomes the entire back surface 30b of the pulley main body 30 constituting the inner surface of the pressure receiving chamber 33, and the pressure receiving area A is expanded.

Since the pulley mechanism applied to the primary pulley is not provided with a spring, the thrust F _pri of the primary pulley mechanism is a hydraulic thrust based on the hydraulic pressure P _pri and the pressure receiving area A _{pri as} shown in the following equation (3). F _p only become.
F _pri = F _p = P _pri × A _pri (3)

  Since the pulley mechanism of this embodiment is applied to the secondary pulley of the belt type continuously variable transmission, the groove width of the groove 4 is widened when the gear ratio is changed to the high side.

  Therefore, in a region where the gear ratio is higher than a certain gear ratio, the pressure receiving area A of the pulley mechanism is reduced, while the pressure receiving area A is increased in the pulley mechanism of the primary pulley.

  Conversely, in a region where the gear ratio is lower than a certain gear ratio, the pressure receiving area A of the pulley mechanism is enlarged, while the pressure receiving area A is reduced in the pulley mechanism of the primary pulley.

Figure 3 is a diagram showing the ratio _{Z (= F pri / F sec} ) about balance thrust ratio Z _b of the characteristics of the thrust of the primary pulley and the secondary pulley.

A thrust ratio Z for holding the balance thrust ratio Z _b is the gear ratio, as shown in FIG. 3, the transmission ratio depends on the drive and coast torque transmission state of the vehicle (torque ratio).

  The torque ratio indicates the ratio of the torque during driving of the vehicle to the maximum torque or the ratio of the torque during coast driving of the vehicle to the maximum torque.

  L represents the lowest gear ratio, H represents the highest gear ratio, and M represents the 1: 1 gear ratio.

By changing the thrust ratio Z from the balance thrust ratio Z _b is changed to a gear ratio corresponding thereto.
If the thrust ratio Z is increased, the gear ratio is shifted to the high side, and if the thrust ratio Z is decreased, the gear ratio is shifted to the low side.

In order to increase the thrust ratio Z, a differential force may be applied so that the primary pulley hydraulic pressure P _pri is increased while the secondary pulley hydraulic pressure P _sec is decreased.

However, as described above, the hydraulic P, since the minimum pressure P _min is set as the lower limit value of the predetermined size, the lower the oil pressure P _sec of the secondary pulley there is a limit.

Moreover, since the _urging force F _spr due to the spring 35 is applied to the pulley mechanism, which is a secondary pulley, the thrust F _sec is obtained by adding the _urging force F _spr to the hydraulic thrust F _p .

In addition, when the gear ratio is set to the high side, the compression of the spring 35 is increased and the _urging force F _spr is also increased.

As a result, it is required to greatly increase the primary pulley hydraulic pressure P _pri , but in the region where the gear ratio is high, the pressure receiving area A _sec is reduced, and the hydraulic thrust F _p decreases accordingly, and the thrust F _sec also decreases.

As a result, the demand for the hydraulic pressure P _pri of the primary pulley is also reduced, so that the energy required for driving the oil pump can be saved by suppressing the discharge pressure of the oil pump.

  An engine-driven oil pump can save fuel consumption of the vehicle, and an electric-driven oil pump can save electricity costs of the vehicle.

From another point of view, the minimum thrust F _min can be reduced, and the generation of excess thrust F _o generated when the minimum thrust F _min is larger than the required thrust F _rq can be suppressed.

  In addition, since said effect is acquired irrespective of the presence or absence of the spring 35, the spring 35 is not essential for this pulley mechanism.

  Further, when the movable pulley 3 moves so that the groove width of the groove 4 is further expanded as shown in FIG. 2B in a state where the first chamber 331 and the second chamber 332 are separated, one direction is provided. Since the oil in the second chamber 332 is discharged to the first chamber 331 through the oil passage 62, the movable pulley 3 operates without any trouble.

  Further, since the oil in the first chamber 331 is prevented from flowing into the second chamber 332, the internal pressure in the divided second chamber 332 is ensured.

  Further, when the movable pulley 3 moves so as to narrow the groove width of the groove 4 from the state where the first chamber 331 and the second chamber 332 are separated, the unidirectional oil passage 61 causes the inside of the centrifugal cancel chamber 41 to be reduced. Since the oil flows into the second chamber 332, the movable pulley 3 operates without any trouble.

  Further, in a state where the first chamber 331 and the second chamber 332 are not separated by the one-way oil passage 61, the oil in the pressure receiving chamber 33 having a higher pressure than that in the centrifugal cancel chamber 41 enters the centrifugal cancel chamber 41. Since the inflow is blocked, the hydraulic pressure in the pressure receiving chamber 33 is maintained.

[2. Second Embodiment]
[2-1. Constitution〕
[2-1-1. Basic configuration)
Next, the configuration of the pulley mechanism according to the second embodiment will be described with reference to FIGS.

  As shown in FIG. 4A, the pulley mechanism is configured in the same manner as in the first embodiment except for the configuration of the pressure receiving chamber dividing means.

  In FIG. 4, the same reference numerals as those in FIG. 1 denote the same components, and the description thereof will be omitted.

[2-1-2. (Configuration of pressure receiving chamber classification means)
Here, the pressure receiving chamber dividing means of this embodiment will be described.

  As shown in FIG. 4, in this embodiment, instead of the seal member 51 and the one-way oil passage 61 of the first embodiment, a lip-attached seal member 71 is provided.

  The seal member 71 has a lip 71 a protruding outward from the outer peripheral portion 32 b of the plunger 32, and the lip 71 a is in pressure contact with the inner peripheral surface 31 a of the cylinder 31.

  The lip 71a is inclined from the centrifugal cancel chamber 41 side toward the second chamber 332 side.

  Thereby, the lip 71a allows the flow of oil from the centrifugal cancel chamber 41 side toward the second chamber 332 side.

  On the contrary, the lip 71a prevents the flow of oil from the second chamber 332 side toward the centrifugal cancel chamber 41 side.

  Therefore, the lip 71 a functions as a check valve, and functions between the outer peripheral portion 32 b and the inner peripheral surface 31 a of the cylinder 31 in the same manner as the one-way oil passage 61.

  In the present embodiment, instead of the seal member 52 and the one-way oil passage 62, a seal member 72 with a lip is provided.

  The seal member 72 has a lip 72 a that protrudes inwardly on the inner peripheral surface of the cylindrical protrusion 321 of the plunger 32, and the lip 72 a is in pressure contact with the outer peripheral surface 311 a of the cylindrical protrusion 311.

  The lip 72a is inclined from the second chamber 332 side toward the first chamber 331 side.

  As a result, the lip 72a allows the flow of oil from the second chamber 332 side toward the first chamber 331 side.

  On the contrary, the lip 72a blocks the flow of oil from the first chamber 331 side toward the second chamber 332 side.

  Therefore, the lip 72a functions as a check valve, and functions between the inner periphery of the cylindrical protrusion 321 and the outer peripheral surface 311a of the cylindrical protrusion 311 in the same manner as the one-way oil passage 62.

[2-2. Action and effect)
Since the pulley mechanism according to the second embodiment of the present invention is configured as described above, in the continuously variable transmission and the vehicle to which the pulley mechanism and the pulley mechanism are applied, An effect can be obtained.

[3. Third Embodiment]
[3-1. Constitution〕
[3-1-1. Basic configuration)
Next, the configuration of the pulley mechanism according to the third embodiment will be described with reference to FIGS.

  As shown in FIG. 5A, the pulley mechanism is configured in the same manner as in the first embodiment except for the configuration of the pressure receiving chamber dividing means.

  In FIG. 5, the same reference numerals as those in FIG. 1 denote the same components, and the description thereof will be omitted.

[3-1-2. (Configuration of pressure receiving chamber classification means)
Here, the pressure receiving chamber dividing means of this embodiment will be described.

  As shown in FIG. 5, in the present embodiment, the cylindrical protrusion 321 of the plunger 32 is omitted, and a seal member 52 and a one-way oil passage are formed on the flange-like portion of the plunger 32 that faces the back surface 30 b of the movable pulley 3. Instead of 62, a seal member 73 with a lip is provided.

  The seal member 73 has a lip 73 a protruding toward the back surface 30 b of the movable pulley 3, and the lip 73 a is in pressure contact with the back surface 30 b of the movable pulley 3.

  The pressure receiving chamber 33 is divided into a first chamber 331 and a second chamber 332 by the lip 73a coming into contact with the back surface 30b.

  The lip 73a is inclined from the second chamber 332 side to the first chamber 331 side.

  Thereby, the lip 73a allows the flow of oil from the second chamber 332 side toward the first chamber 331 side.

  Conversely, the lip 73a blocks the flow of oil from the first chamber 331 side toward the second chamber 332 side.

  Accordingly, the lip 73a functions as a check valve, and there is a unidirectional oil passage 61 between the inner peripheral surface of the cylindrical projection 321 and the inner peripheral surface 31a of the cylinder 31 and the outer peripheral surface 311a of the cylindrical projection 311. Works equally well.

[3-2. Action and effect)
Since the pulley mechanism according to the third embodiment of the present invention is configured as described above, in the continuously variable transmission and the vehicle to which the pulley mechanism and the pulley mechanism are applied, An effect can be obtained.

[4. Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  Each structure of embodiment mentioned above can be selected as needed, and may be combined suitably.

  In the above-described embodiment, the example in which the pulley mechanism is applied to the secondary pulley has been described. However, the pulley mechanism may be applied to the primary pulley.

  Further, similarly to the case where the spring 35 is not essential, the cylindrical protrusions 311, 321, the recess 312 and the one-way oil passages 61, 62 are not essential.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Fixed pulley 3 Movable pulley 4 Groove 5 Belt 11,12 Oil path 20,30 Pulley main-body part 20a, 30a Opposite surface (sheave surface)
33 Pressure receiving chamber 35 Spring 40 Cancel plate 41 Centrifugal cancel chamber 61, 62 One-way oil passage 311 Cylindrical protrusion (first cylindrical protrusion)
312 Recess 321 Cylindrical protrusion (second cylindrical protrusion)
331 First chamber 332 Second chamber 51, 52 Seal member 71, 72, 73 Seal member with lip

Claims (8)

A plunger,
Having a fixed pulley,
A movable pulley between the plunger and the fixed pulley;
Having a groove between the fixed pulley and the movable pulley;
Having a pressure receiving chamber between the movable pulley and the plunger;
Has an oil passage,
When the width of the groove is less than a predetermined value, the oil passage supplies oil to the pressure receiving chamber,
When the width of the groove is equal to or greater than the predetermined value, the pressure receiving chamber is divided into a first chamber and a second chamber, and the oil passage supplies oil to the first chamber. Pulley mechanism. A plunger,
Having a fixed pulley,
A movable pulley between the plunger and the fixed pulley;
Having a groove between the fixed pulley and the movable pulley;
Biasing means for applying a thrust to the movable pulley;
Having a pressure receiving chamber between the movable pulley and the plunger;
Has an oil passage,
When the thrust is less than a predetermined value, the oil passage supplies oil to the pressure receiving chamber,
When the thrust is equal to or greater than the predetermined value, the pressure receiving chamber is divided into a first chamber and a second chamber, and the oil passage supplies oil to the first chamber. . The movable pulley has a cylindrical portion,
The movable pulley has a first cylindrical projection portion inward of the cylindrical portion,
The plunger has an outer peripheral portion that is in sliding contact with an inner peripheral surface of the cylindrical portion,
The plunger has a second cylindrical protrusion inside the outer peripheral portion,
The pressure receiving chamber is divided into the first chamber and the second chamber when the first cylindrical projection and the second cylindrical projection are close to each other. Or the pulley mechanism of 2. The pulley mechanism according to claim 3, wherein the movable pulley has a recess capable of accommodating the second cylindrical protrusion. Has a centrifuge cancellation chamber,
The pulley mechanism according to any one of claims 1 to 4, further comprising a first one-way oil passage through which oil can flow from the centrifugal cancel chamber toward the second chamber. The pulley mechanism according to any one of claims 1 to 5, further comprising a second one-way oil passage through which oil can flow from the second chamber toward the first receiving chamber. A continuously variable transmission comprising the pulley mechanism according to any one of claims 1 to 6. A vehicle comprising the continuously variable transmission according to claim 7.

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