JP2018128080A - Power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To promote cost reduction, size reduction and weight reduction, in a power transmission device which can switch a power transmission state via a continuously variable transmission and a power transmission state via a fixed gear stage.SOLUTION: This power transmission device for a vehicle comprises: a continuously variable transmission having a primary-side pulley, a secondary-side pulley and a winding member wound between the primary-side pulley and the secondary-side pulley; a fixed gear stage whose gear ratio is fixed; and a transmission changeover part for switching a first transmission state for transmitting power from an input shaft to an output shaft via the continuously variable transmission, and a second transmission state for transmitting the power via the fixed gear stage by using a movable connecting member which is displaceable to an axial direction in conjunction with a movable sheave of the primary-side pulley or a movable sheave of the secondary-side pulley.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power transmission device in a vehicle, and more particularly to a technical field for switching between a power transmission state via a continuously variable transmission and a power transmission state via a fixed gear.

  For example, a continuously variable transmission of a winding type in which a winding member such as a belt or a chain is wound between two pulleys on a primary side (primary) and a secondary side (secondary) is known.

In the wrapping type continuously variable transmission, the necessary wrapping member clamping force is secured by the primary pulley during overdrive when the gear ratio is less than 1, for example. At this time, in the hydraulic system of the vehicle, the hydraulic pressure (primary pressure) to be supplied to the primary pulley to ensure the clamping force is the maximum hydraulic pressure, so the line is adjusted based on the hydraulic pressure discharged from the oil pump. The pressure needs to be at least the primary pressure.
For this reason, the oil pump drive torque cannot be reduced in a driving state in which the driving in the overdrive state is maintained for a long time, such as during high-speed cruising, and high-speed cruising is being performed in a vehicle that drives the oil pump based on engine power. It is difficult to improve the fuel consumption rate.

  Therefore, conventionally, a continuously variable transmission of a winding type is provided with a fixed gear stage for high-speed traveling, and the power from the input shaft is transmitted to the output shaft via the continuously variable transmission except during overdrive, A configuration has been proposed in which the power is transmitted to the output shaft through a fixed gear stage during driving (see, for example, Patent Document 1 below).

Japanese Patent Laying-Open No. 2015-175479

  When switching between the power transmission state via the continuously variable transmission and the power transmission state via the fixed gear stage, the movable connecting member for realizing the switching is driven by an electromagnetic actuator or hydraulic pressure. It is possible.

  However, when switching the power transmission state, it is not desirable to add an electromagnetic actuator or a hydraulic drive unit because this increases the cost, size and weight of the power transmission device.

  The present invention has been made in view of the above-described problems, and relates to a power transmission device that enables switching between a power transmission state via a continuously variable transmission and a power transmission state via a fixed gear. It aims at reduction, size reduction, and weight reduction.

  A power transmission device according to the present invention is a power transmission device for a vehicle, and includes a primary pulley, a secondary pulley, and a winding member that is wound between the primary pulley and the secondary pulley. A continuously variable transmission having a fixed gear ratio and a movable sheave of the primary pulley or a movable sheave of the secondary pulley that is movable in the axial direction. Transmission that switches between a first transmission state in which power from the input shaft is transmitted to the output shaft through the continuously variable transmission and a second transmission state in which the power is transmitted through the fixed gear stage by the connecting member. And a switching unit.

  Thus, when switching between the first transmission state and the second transmission state, it is not necessary to separately add an electromagnetic actuator or a hydraulic drive unit as a drive unit of the movable connecting member.

  In the above-described power transmission device according to the present invention, the movable connection member includes a first connection part and a second connection part that are spaced apart in the axial direction, and the transmission switching part includes the first connection part. A first connected member having a first connected part connected to the first connecting part in one transmission state and a second connected part connected to the second connecting part in the second transmission state. In addition to having two connected members, the first connecting part and the first connected part, and the second connecting part and the second connected part can be configured as a synchromesh mechanism. is there.

  Thereby, the vibration and noise accompanying switching of the power transmission state can be reduced.

  In the above-described power transmission device according to the present invention, the movable connecting member may be connected to the movable sheave of the primary pulley.

  Thereby, unlike the case where the movable connecting member is connected to the movable sheave of the secondary pulley, the power of the input shaft is transmitted to the next shaft (the shaft coaxially arranged with the secondary pulley) in the second transmission state. No gear is required.

  The power transmission device according to the present invention includes a reduction gear portion that decelerates the output of the continuously variable transmission and transmits it to the output shaft, and the gear ratio of the fixed gear step is the gear ratio of the reduction gear portion. It is possible to adopt a configuration that matches the reciprocal of.

  Thus, in the second transmission state via the fixed gear stage, the primary pulley and the secondary pulley are rotated at the same rotational speed.

  The power transmission device according to the present invention described above includes a torque control unit that reduces input torque from the engine of the vehicle to the input shaft when switching between the first transmission state and the second transmission state. Is possible.

  Thereby, the vibration and noise accompanying switching of the power transmission state can be reduced.

  According to the present invention, a power transmission device that enables switching between a power transmission state via a continuously variable transmission and a power transmission state via a fixed gear stage can be reduced in cost, size, and weight. be able to.

It is the figure which showed the structure outline | summary of the vehicle provided with the power transmission device as embodiment which concerns on this invention. It is the schematic longitudinal cross-sectional view which cut | disconnected the transmission transmission mechanism in embodiment along the axial direction. Similarly, it is the schematic longitudinal cross-sectional view which cut | disconnected the transmission mechanism in embodiment along an axial direction. It is the schematic longitudinal cross-sectional view showing the structure of the transmission transmission mechanism in embodiment by the skeleton figure. Similarly, it is the schematic longitudinal cross-sectional view which represented the structure of the transmission transmission mechanism in embodiment with the skeleton figure. It is the schematic longitudinal cross-sectional view which represented the structure of the transmission transmission mechanism as a 1st modification with the skeleton figure. Similarly, it is the schematic longitudinal cross-sectional view which represented the structure of the transmission transmission mechanism as a 1st modification with the skeleton figure. It is the schematic longitudinal cross-sectional view showing the structure of the transmission transmission mechanism as a 2nd modification with the skeleton figure. Similarly, it is the schematic longitudinal cross-sectional view which represented the structure of the transmission transmission mechanism as a 2nd modification with the skeleton figure.

<1. General configuration of vehicle>
FIG. 1 is a diagram illustrating a schematic configuration of a vehicle 1 including a power transmission device as an embodiment according to the present invention. In FIG. 1, only the configuration of the main part according to the present invention is extracted from the configuration of the vehicle 1.
In the present embodiment, the power transmission device includes at least the transmission transmission mechanism 6.

  The vehicle 1 includes an engine 2 as a driving power source, a torque converter 4, a forward / reverse switching mechanism 5, a power transmission mechanism 3 having a speed change transmission mechanism 6, and hydraulic control for hydraulic pressure control of hydraulic oil in the power transmission mechanism 3. A portion 7, a gear 8 and a gear 9, a differential gear 10, a drive wheel 11 a and a drive wheel 11 b, an engine control unit 12, a transmission mechanism control unit 13, and a bus 14 are provided.

  The engine 2 is a traveling power source (prime mover) that causes the vehicle 1 to travel, and generates power that consumes fuel and acts on the drive wheels 11 a and 11 b of the vehicle 1. The engine 2 burns fuel to generate mechanical power (engine torque) on a crankshaft 2a that is an engine output shaft, and the mechanical power can be output from the crankshaft 2a toward the drive wheels 11a and 11b. Has been.

The power transmission mechanism 3 is provided in a power transmission path from the engine 2 to the drive wheels 11a and 11b, and transmits power from the engine 2 to the drive wheels 11a and 11b. Oil (hydraulic oil) as a liquid medium Operated by hydraulic pressure.
In the power transmission mechanism 3, the crankshaft 2 a of the engine 2 and the input shaft Is of the transmission transmission mechanism 6 are connected via the torque converter 4, the forward / reverse switching mechanism 5, and the output shaft Os of the transmission transmission mechanism 6 is a gear. 8 and a gear 9, a differential gear 10 and the like are connected to driving wheels 11a and 11b.

  The torque converter 4 is disposed between the engine 2 and the forward / reverse switching mechanism 5 and is configured to amplify (or maintain) the power torque transmitted from the engine 2 and transmit the torque to the forward / reverse switching mechanism 5. Has been. The torque converter 4 includes a pump impeller 4a and a turbine runner 4b that are rotatably arranged opposite to each other, and the pump impeller 4a is coupled to the crankshaft 2a via the front cover 4c so as to be rotatable together with the turbine runner 4b. It is configured to be connected to the mechanism 5. Along with the rotation of the pump impeller 4a and the turbine runner 4b, a viscous fluid such as hydraulic fluid interposed between the pump impeller 4a and the turbine runner 4b circulates to allow a differential between the input and output. However, the torque can be amplified and transmitted.

  The torque converter 4 further includes a lock-up clutch 4d provided between the turbine runner 4b and the front cover 4c and connected to the turbine runner 4b so as to be integrally rotatable. The lock-up clutch 4d is operated by the pressure of hydraulic oil supplied from the hydraulic control unit 7, and is switched between an engaged state (lock-up ON) and an open state (lock-up OFF) with the front cover 4c. In a state where the lock-up clutch 4d is engaged with the front cover 4c, the front cover 4c (that is, the pump impeller 4a) and the turbine runner 4b are engaged, and the relative rotation between the pump impeller 4a and the turbine runner 4b is restricted, Since the differential between the input and the output is prohibited, the torque converter 4 transmits the torque transmitted from the engine 2 to the forward / reverse switching mechanism 5 as it is.

  The forward / reverse switching mechanism 5 is configured to be able to change the power (rotation output) from the engine 2 and to switch the rotation direction of the power. The forward / reverse switching mechanism 5 includes a planetary gear mechanism 5a, a forward / reverse switching clutch (forward clutch) CL as a friction engagement element, a forward / reverse switching brake (reverse brake) BR, and the like. The planetary gear mechanism 5a is a differential mechanism that includes a sun gear, a ring gear, a carrier, and the like as a plurality of rotational elements that can rotate differentially with each other. The forward / reverse switching clutch CL and the forward / reverse switching brake BR include planetary gears. It is an engagement element for switching the operating state of the gear mechanism 5a, and can be constituted by, for example, a frictional engagement mechanism such as a multi-plate clutch.

In the forward / reverse switching mechanism 5, the forward / reverse switching clutch CL and the forward / reverse switching brake BR are operated by the pressure of the hydraulic oil supplied from the hydraulic control unit 7, and the operating state is switched. Specifically, the forward / reverse switching mechanism 5 rotates the power from the engine 2 in the normal direction when the forward / reverse switching clutch CL is in an engaged state (ON state) and the forward / backward switching brake BR is in a released state (OFF state). (The direction in which the input shaft Is rotates when the vehicle 1 moves forward) is transmitted to the input shaft Is. On the other hand, the forward / reverse switching mechanism 5 reversely rotates the power from the engine 2 when the forward / reverse switching clutch CL is disengaged and the forward / reverse switching brake BR is engaged (the input shaft Is when the vehicle 1 moves backward). Is transmitted to the input shaft Is. In the forward / reverse switching mechanism 5, both the forward / reverse switching clutch CL and the forward / reverse switching brake BR are released during neutral.
In the drawing, the control system for controlling the engagement / release of the forward / reverse switching clutch CL and the forward / reverse switching brake BR is collectively referred to as “CB control system 5b”.

The transmission transmission mechanism 6 is provided between the forward / reverse switching mechanism 5 and the drive wheels 11a and 11b in the power transmission path from the engine 2 to the drive wheels 11a and 11b, and continuously transmits the power from the input shaft Is ( A continuously variable transmission 6a that shifts continuously and a fixed gear stage 6b that shifts the power from the input shaft Is by a fixed gear ratio (speed ratio) are provided.
The transmission transmission mechanism 6 has a first transmission state in which power from the input shaft Is is transmitted to the output shaft Os through the continuously variable transmission 6a, and a second transmission state in which the power is transmitted through the fixed gear stage 6b. However, a specific configuration will be described later.

  Although not shown in FIG. 1, the continuously variable transmission 6 includes a primary pulley (primary pulley) 61 and a secondary shaft (secondary shaft) Ss provided with respect to the primary shaft (primary shaft) Ps. A secondary pulley (secondary pulley) 64 provided for the belt, a belt 67 or a chain member such as a belt that is stretched (wound) between the primary pulley 61 and the secondary pulley 64. The winding type continuously variable transmission (Continuously Variable Transmission = CVT) is configured.

  The power transmitted to the output shaft Os in the transmission mechanism 6 is transmitted to the differential gear 10 via the gear 8 and the gear 9. The differential gear 10 transmits the transmitted power to the drive wheels 11a and 11b via each drive shaft. The differential gear 10 absorbs the rotational speed difference between the drive wheels 11a and 11b that occurs when the vehicle 1 turns.

  With the above configuration, in the vehicle 1, the power generated by the engine 2 can be transmitted to the drive wheels 11 a and 11 b via the torque converter 4, the forward / reverse switching mechanism 5, the transmission mechanism 6, the differential gear 10, and the like. it can. As a result, the vehicle 1 can travel by driving force [N] generated on the contact surface with the road surface of the drive wheels 11a and 11b.

The hydraulic control unit 7 uses a hydraulic oil pressure to lock the clutch 4d of the torque converter 4, the forward / reverse switching clutch CL and the forward / reverse switching brake BR of the forward / reverse switching mechanism 5, and the primary movable sheave described later of the continuously variable transmission 6a. The power transmission mechanism 3 including 63 and the secondary side movable sheave 66 is operated.
The hydraulic control unit 7 includes a plurality of oil passages, an oil reservoir, an oil pump, a plurality of electromagnetic valves, and the like, and is supplied to each part of the power transmission mechanism 3 according to a signal from the transmission mechanism control unit 13. Control hydraulic oil flow rate and hydraulic pressure. Further, the hydraulic control unit 7 also functions as a lubricating oil supply device that lubricates predetermined portions of the power transmission mechanism 3.
In this example, the oil pump as a hydraulic oil supply source is driven based on the power of the engine 2.

  The engine control unit 12 and the transmission mechanism control unit 13 include a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and a CAN (Controller Area Network). Are connected to each other via a bus 14 corresponding to a predetermined in-vehicle network communication standard.

The engine control unit 12 performs various operation controls such as fuel injection control, ignition control, and intake air amount adjustment control for the engine 2. Specifically, various operation controls for the engine 2 are performed by controlling various actuators (for example, a throttle actuator that drives a throttle valve, an injector that performs fuel injection, etc.) provided in the engine 2.
The engine control unit 12 communicates with the transmission mechanism control unit 13 and outputs data relating to the operating state of the engine 2 to the transmission mechanism control unit 13 as necessary. Further, if necessary, the operation control of the engine 2 is performed based on various signals from the transmission mechanism control unit 13.

The transmission mechanism control unit 13 controls the operation of each part of the power transmission mechanism 3, such as the torque converter 4, the forward / reverse switching mechanism 5, and the continuously variable transmission 6a, by controlling the hydraulic control unit 7.
In particular, the transmission mechanism control unit 13 performs gear ratio control of the continuously variable transmission 6a. Specifically, the transmission mechanism control unit 13 obtains a target speed ratio of the continuously variable transmission 6 based on information such as the engine speed and the accelerator opening, for example, and a primary pressure (primary pressure) for realizing the target speed ratio. The hydraulic pressure control unit 7 is instructed so as to obtain the primary pressure and the secondary pressure.
Further, the transmission mechanism control unit 13 instructs the hydraulic control unit 7 to drive the hydraulic pressure of the CB control system 5b in the forward / reverse switching mechanism 5 to engage / release the forward / reverse switching clutch CL and the forward / reverse switching brake BR. Let it run.

<2. Configuration of transmission mechanism>
2 and 3 are schematic longitudinal sectional views of the transmission mechanism 6. FIG. 2 shows a state in which the transmission ratio of the continuously variable transmission 6a is substantially maximum (substantially lowest), and FIG. Each state shows a predetermined gear ratio (eg, “1”) or less as an overdrive state.

  The transmission mechanism 6 includes a continuously variable transmission 6a, a fixed gear stage 6b, a transmission control unit 6c for switching between the first transmission state and the second transmission state, and an output of the continuously variable transmission 6a. And a reduction gear portion 6d for transmitting the output to the output shaft Os.

  In the continuously variable transmission 6a, the primary pulley 61 is fixed at a position relative to the primary shaft Ps and can be displaced in the axial direction of the primary shaft Ps, and a primary fixed sheave 62 that rotates integrally coaxially with the primary shaft Ps. The primary side movable sheave 63 is coaxially arranged oppositely. The secondary pulley 64 is fixed at a position relative to the secondary shaft Ss and can be displaced in the axial direction of the secondary shaft Ss, and a secondary fixed sheave 65 that rotates integrally with the secondary shaft Ss. The secondary movable sheave 66 is coaxially arranged oppositely. The winding member 67 has a substantially V-shaped groove (hereinafter referred to as “V-groove”) formed between the primary fixed sheave 62 and the movable sheave 63 and between the secondary fixed sheave 65 and the movable sheave 66. (Noted).

  In the continuously variable transmission 6a of this example, the primary side fixed sheave 62 is formed integrally with the primary side shaft Ps, and the secondary side fixed sheave 65 is formed integrally with the secondary side shaft Ss. The primary side movable sheave 63 is slidable in the axial direction via a sliding guide such as a spline groove, and the secondary side movable sheave 66 is slidable on the primary side shaft Ps and the secondary side shaft Ss.

In the continuously variable transmission 6 a, a primary hydraulic chamber 68 is provided as a hydraulic chamber for applying hydraulic pressure to the primary movable sheave 63, and a secondary hydraulic chamber is provided as a hydraulic chamber for applying hydraulic pressure to the secondary movable sheave 66. 69 is provided. In the drawing, the hydraulic chamber wall of the primary hydraulic chamber 68 is shown as a hydraulic chamber wall W68, and the hydraulic chamber wall of the secondary hydraulic chamber 69 is shown as a hydraulic chamber wall W69.
The primary hydraulic chamber 68 is supplied with a hydraulic pressure as a primary pressure, and the secondary hydraulic chamber 71 is supplied with a hydraulic pressure as a secondary pressure. In gear ratio control, the primary movable sheave 63 approaches the primary fixed sheave 62 by adjusting the hydraulic pressure so that the primary pressure gradually increases relative to the secondary pressure, and the secondary pressure The side movable sheave 66 moves away from the secondary fixed sheave 65, the primary side winding diameter gradually increases, the secondary side winding diameter gradually decreases, and the gear ratio gradually decreases (high side and Become). Conversely, by adjusting the hydraulic pressure so that the secondary pressure gradually increases relative to the primary pressure, the primary movable sheave 63 moves away from the primary fixed sheave 62, and the secondary movable sheave 66 The secondary side fixed sheave 65 approaches, the primary side winding diameter gradually decreases, the secondary side winding diameter gradually increases, and the gear ratio gradually increases (becomes the LOW side).

In this example, the axial directions of the primary side shaft Ps and the secondary side shaft Ss coincide with the longitudinal direction of the vehicle 1. In the primary pulley 61, the primary movable sheave 63 is positioned in front of the primary fixed sheave 62, and in the secondary pulley 64, the secondary movable sheave 65 is in the rear of the secondary fixed sheave 66. Is located.
For this reason, when the transmission ratio of the continuously variable transmission 6a increases, the primary movable sheave 62 is displaced forward and the secondary movable sheave 66 is displaced rearward by the hydraulic control described above. Conversely, when the gear ratio of the continuously variable transmission 6a is reduced, the primary movable sheave 62 is displaced rearward and the secondary movable sheave 66 is displaced forward.

  Here, the central portion of the primary shaft Ps in the direction orthogonal to the axis is penetrated in the axial direction, and the input shaft Is is inserted coaxially with the primary shaft Ps through the penetrated portion. The primary shaft Ps is held by, for example, the input shaft Is, is rotatable with respect to the input shaft Is, and the position in the axial direction is fixed.

The fixed gear stage 6b includes an external gear 71 arranged coaxially with the input shaft Is, a ring-shaped gear 72 as a double-tooth gear having internal teeth and external teeth, and external teeth that rotate integrally with the output shaft Os. And a gear 73a.
In the external gear 71, the central portion in the direction perpendicular to the axis is penetrated in the axial direction, the input shaft Is is inserted through the penetrated portion, and is held by the input shaft Is. The external gear 71 is rotatable with respect to the input shaft Is, and its axial position is fixed.
The external gear 71 has a first external tooth portion 71a located on the front side as an external tooth portion on which a plurality of external teeth are formed, and a second external tooth portion 71b located on the rear side.
In this example, the first external gear 71 corresponds to the “second connecting member” in the claims, and the first external tooth portion 71 a corresponds to the “second connecting portion”.

The ring-shaped gear 72 has an internal tooth portion 72a in which a plurality of internal teeth are formed and an external tooth portion 72b in which a plurality of external teeth are formed, and the external gear 73 has a plurality of external teeth. And has an external tooth portion 73a.
In the ring-shaped gear 72, the internal teeth at the internal tooth portion 72 a mesh with the external teeth at the external tooth portion 71 b of the external gear 71, and the external teeth at the external tooth portion 72 b are external teeth at the external tooth portion 73 a of the external gear 73. Is engaged.

  The gear ratio of the fixed gear stage 6b is set to a gear ratio that realizes a gear ratio equal to or lower than a predetermined gear ratio corresponding to the overdrive state. Specifically, it is a gear ratio that realizes a gear ratio that is equal to or smaller than a “speed ratio Rth” described later.

  The reduction gear portion 6d is positioned rearward of the secondary pulley 64 and is positioned forward of the external gear 73 of the fixed gear stage 6b and the first gear 81 that rotates integrally with the secondary shaft Ss. A second gear 82 that rotates integrally coaxially with the shaft Os is provided, and external teeth of the first gear 81 and the second gear 82 are meshed with each other.

  The transmission switching unit 6c includes a first connected member 74 that is positioned forward of the primary pulley 61 and rotates integrally with the input shaft Is, and an external gear 71 of the fixed gear stage 6b behind the primary shaft Ps. The external gear 75 that is positioned further forward and rotates integrally with the input shaft Is, the first connecting portion 76, the second connecting portion 77, and the first connecting portion 76 and the second connecting portion 77 are connected. A movable connecting member 79 having a portion 78 and being axially displaceable is provided.

  The first connected member 74 has an external tooth portion 74a in which a plurality of external teeth are formed, and the external gear 75 has an external tooth portion 75a in which a plurality of external teeth are formed.

The first connecting portion 76 of the movable connecting member 79 has a substantially ring-shaped outer shape coaxial with the input shaft Is, and has an inner tooth portion 76a in which a plurality of inner teeth are formed on the inner peripheral surface side.
The first connecting portion 76 is axially displaceable in conjunction with the primary side movable sheave 63 and rotates integrally with the primary side movable sheave 63 coaxially.
Specifically, the primary side movable sheave 63 of this example includes a winding portion 63a that is positioned at the rear end portion and has a conical surface as a winding surface of the winding member 67, and forward from the outer peripheral portion of the winding portion 63a. The first connecting portion 76 has a rear end fixed to the outer peripheral surface of the front end of the extending portion 63b, and the primary movable sheave 63. In conjunction with the rotation, it can be displaced in the axial direction and is rotated integrally with the primary movable sheave 63.
The internal tooth portion 76a in the first connecting portion 76 is located in front of the front end of the extending portion 63b.

The second connecting portion 77 has a substantially ring-shaped outer shape coaxial with the input shaft Is, similarly to the first connecting portion 76, and has an inner tooth portion 77a in which a plurality of inner teeth are formed on the inner peripheral surface side. ing.
The connecting portion 78 is a substantially rod-like or substantially plate-like portion extending in the axial direction, the front end portion is connected to the first connecting portion 76, and the rear end portion is connected to the second connecting portion 77. Here, the connecting portion 78 is fixed in a position around the axis, and connects the first connecting portion 76 and the second connecting portion 77 so as to be rotatable coaxially with the input shaft Is. When the connecting portion 78 rotates together with the first connecting portion 76 and the second connecting portion 77, the connecting portion 78 is buffered with the winding member 67, so that the prevention is intended.

  The second connecting portion 77 is connected to the first connecting portion 76 via the connecting portion 78, so that it can be displaced in the axial direction in conjunction with the primary side movable sheave 62. In this example, the second connecting portion 77 is configured so that the inner teeth of the inner tooth portion 77a are external to the outer tooth portion 75a of the outer gear 75 even when the primary movable sheave 62 is in any position within the movable range in the axial direction. It is positioned to mesh with the teeth.

The first external tooth portion of the internal gear portion 76a of the first connecting portion 76 and the external tooth portion 74a of the first connected member 74, and the internal gear portion 77a of the second connecting portion 77 and the external gear 71 of the fixed gear stage 6b. In each of the 71a, the inner teeth and the outer teeth are engaged / disengaged in accordance with the axial displacement of the primary movable sheave 62.
In this example, the internal tooth portion 76a and the external tooth portion 74a, and the internal tooth portion 77a and the first external tooth portion 71a, respectively, are rotational differences between the first connecting portion 76 and the first connected member 74 at the time of meshing. The synchromesh mechanism is configured to absorb the rotational difference between the second connecting portion 77 and the external gear 71 (corresponding to the second connected member).

  In the transmission transmission mechanism 6 configured as described above, the gear ratio of the continuously variable transmission 6a is less than or equal to a predetermined gear ratio (hereinafter referred to as “speed ratio Rth”) corresponding to the overdrive state. Thus, the power transmission state via the continuously variable transmission 6a and the power transmission state via the fixed gear stage 6b are switched.

Specifically, in a state where the transmission gear ratio of the continuously variable transmission 6a is larger than the transmission gear ratio Rth (non-overdrive state), as shown in FIG. The first connected member 74 is engaged with external teeth in the external tooth portion 74 a, and the power from the input shaft Is is transmitted to the primary movable sheave 61 via the first connected member 74 and the first connecting portion 76. .
On the other hand, the internal teeth in the internal tooth portion 77a of the second connecting portion 77 mesh with the external teeth in the external tooth portion 75a of the external gear 75, but the external gear 71 provided in the fixed gear stage 6b. It does not mesh with the external teeth in the first external tooth portion 71a. That is, the power from the input shaft Is is not transmitted to the fixed gear stage 6b.

The torque flow in this case is represented by the skeleton diagram of FIG.
As shown in the figure, the power from the input shaft Is in this case is transmitted to the output shaft Os through the first connected member 74 → the first connecting portion 76 → the continuously variable transmission 6a → the reduction gear portion 6d.

When the transmission gear ratio of the continuously variable transmission 6a is equal to or less than the transmission gear ratio Rth, the primary movable sheave 62 is displaced rearward from the case of FIG. The teeth are engaged with both external teeth of the first external tooth portion 71a of the external gear 71 and the external tooth portion 71a of the external gear 71, and the power from the input shaft Is is transmitted between the external gear 75 and the second connecting portion 77. To the fixed gear stage 6b (see FIG. 3).
On the other hand, the meshing state between the internal teeth at the internal tooth portion 76a of the first connecting portion 76 and the external teeth at the external tooth portion 74a of the first connected member 74 is eliminated, and the power from the input shaft Is is connected to the first connected portion. It is not transmitted to the primary side movable sheave 61 via the member 74 and the first connecting portion 76.

  As represented by the skeleton diagram of FIG. 5, the power from the input shaft Is in this case is transmitted to the output shaft Os via the external gear 75 → the second connecting portion 77 → the fixed gear stage 6b.

As described above, the transmission mechanism 6 is configured so that the power from the input shaft Is is output to the output shaft via the continuously variable transmission 6a by the movable connecting member 79 that is axially displaceable in conjunction with the primary movable sheave 62. A transmission switching unit 6c that switches between a first transmission state to be transmitted to Os and a second transmission state to transmit the power via the fixed gear stage 6b is provided.
Since the movable connecting member 79 is displaced in conjunction with the primary side movable sheave 62, it is not necessary to separately add an electromagnetic actuator or a hydraulic driving unit as a driving unit for the movable connecting member 79.
Therefore, the power transmission device that enables switching between the power transmission state via the continuously variable transmission 6a and the power transmission state via the fixed gear stage can be reduced in cost, size, and weight. .

Further, since it is shifted to the direct drive by the fixed gear stage 6b corresponding to the overdrive, it is not necessary to maintain a relatively high drive hydraulic pressure for maintaining the overdrive state in the continuously variable transmission 6a.
Therefore, the load on the engine 2 as the oil pump drive source is reduced, and the fuel efficiency is improved.
In the case of this embodiment, the drive hydraulic pressure of the continuously variable transmission 6a at the time of overdrive may be a hydraulic pressure necessary to maintain the position of the primary movable sheave 62 at the position shown in FIG. 3 or FIG.

In the transmission mechanism 6, the first connecting portion 76 and the external tooth portion 74a of the first connected member 74, and the second external connecting portion 77 and the first external tooth portion 71a of the external gear 71 of the fixed gear stage 6b. Is configured as a synchromesh mechanism.
Thereby, the vibration and noise accompanying switching of the power transmission state can be reduced.

Here, the continuously variable transmission 6a of the present example is configured such that the primary side movable sheave 62 can be displaced rearward from the position in the state where the gear ratio = the gear ratio Rth.
Thereby, in the overdrive state (second transmission state), it is possible to enlarge the meshing area between the inner tooth portion 77a and the first outer tooth portion 71a, and the connection state between the input shaft Is and the fixed gear stage 6b. It can be made stronger.

Further, in this example, the gear ratio of the fixed gear stage 6b is set to coincide with the reciprocal of the gear ratio of the reduction gear section 6d.
Thereby, in the second transmission state via the fixed gear stage 6b, the primary pulley 61 and the secondary pulley 64 are rotated at the same rotational speed. That is, it is possible to prevent the winding member 67 from slipping due to the differential rotation of the primary pulley 61 and the secondary pulley 64.
In the second transmission state, the rotation of the output shaft Os is transmitted to the secondary pulley 64 via the reduction gear portion 6d, and the primary pulley 61 and the secondary pulley 64 are idled.

Although illustration is omitted, in the power transmission device in the present embodiment, control is performed to reduce the input torque from the engine 2 to the input shaft Is in order to mitigate vibration and noise associated with switching of the power transmission state.
In this example, the control is performed by cooperation between the engine control unit 12 and the transmission mechanism control unit 13. Specifically, the engine control unit 12 inputs, for example, the information on the target speed ratio described above that is determined by the transmission mechanism control unit 13, and exceeds the speed ratio Rth when the target speed ratio decreases below the speed ratio Rth. In each case, control for temporarily reducing the output of the engine 2 is performed. Thereby, the input torque from the engine 2 to the input shaft Is can be reduced corresponding to the switching between the first transmission state and the second transmission state.

Note that the method of reducing the input torque from the engine 2 to the input shaft Is is not limited to the example in which the output control of the engine 2 is performed as described above. For example, the forward / reverse switching mechanism 5 is temporarily set to the neutral state. It is also possible to adopt other methods such as (to make both the forward / reverse switching clutch CL and the forward / reverse switching brake BR open).
In this way, when the method of setting the forward / reverse switching mechanism 5 to be neutral is employed, the control body is the transmission mechanism control unit 13.

In the torque reduction control as described above, a value based on actual measurement can be used as the speed change ratio. For example, it is conceivable to provide means for detecting the rotational speeds of the primary pulley 61 and the secondary pulley 64 and perform torque reduction control based on the speed ratio obtained from the detected rotational speed.
Also, a means for detecting the axial position of the primary movable sheave 63 is provided, and torque reduction control is executed when it is determined that the primary movable sheave 63 has reached a predetermined position based on the position detection result by the means. Is also possible.

<3. Modification of Embodiment>
Here, in the above description, the example of the configuration of the transmission mechanism 6 corresponding to the three-axis configuration including the input shaft Is (primary shaft Ps), the secondary shaft Ss, and the output shaft Os is shown. A transmission transmission mechanism 6A corresponding to a four-axis configuration as shown in FIG.

6 and 7 are skeleton diagrams showing the configuration of the transmission mechanism 6A as a first modification as a schematic longitudinal sectional view. FIG. 6 shows the transmission ratio of the continuously variable transmission 6a as in FIG. FIG. 7 shows a state where the gear ratio is equal to or less than a predetermined gear ratio as an overdrive state, as in FIG.
In the following description, parts that are the same as the parts that have already been described are assigned the same reference numerals, and descriptions thereof are omitted.

  The transmission transmission mechanism 6A has a third shaft Ts added to the transmission transmission mechanism 6 and a reduction gear portion 6dA instead of the reduction gear portion 6d. The difference is that 84 is added.

  The reduction gear portion 6dA includes a first gear 81A that rotates integrally with the secondary shaft Ss and a second gear 82A that rotates integrally with the third shaft Ts, and the first gear 81A and the second gear 82A. The external teeth are meshed with each other.

  The inter-shaft connecting gear 83 and the inter-shaft connecting gear 84 rotate together coaxially with the third shaft Ts and the output shaft Os, respectively. The inter-shaft connecting gear 83 and the inter-shaft connecting gear 84 are meshed with the same external teeth. .

  In this case, the external gear 73 in the fixed gear stage 6 b is provided so as to rotate integrally with the third shaft Ts, and the external teeth of the external tooth 73 a of the external gear 73 are external teeth 72 b of the ring gear 72. Is meshed with external teeth.

Also in the transmission mechanism 6A as described above, when the transmission ratio of the continuously variable transmission 6a is larger than the transmission ratio Rth, the power from the input shaft Is is transmitted to the first connected member 74, the first connecting portion 76, and the like. On the other hand, the internal teeth of the internal teeth 77a of the second connecting portion 77 mesh with the external teeth of the external teeth 75a of the external gear 75, but are fixed. The external teeth in the first external tooth portion 71a of the external gear 71 provided in the gear stage 6b are not meshed, and the power from the input shaft Is is not transmitted to the fixed gear stage 6b.
As shown in FIG. 6, the power from the input shaft Is in this case is as follows: first connected member 74 → first connecting portion 76 → continuously variable transmission 6a → reduction gear portion 6d → interaxial connecting gears 83 and 84. To the output shaft Os.

When the transmission gear ratio of the continuously variable transmission 6a is equal to or less than the transmission gear ratio Rth, the power from the input shaft Is passes through the external gear 75 and the second connecting portion 77 as the primary movable sheave 62 is displaced rearward. On the other hand, the meshing state between the internal teeth in the internal tooth portion 76a of the first connecting portion 76 and the external teeth in the external tooth portion 74a of the first connected member 74 is eliminated, and the input shaft The power from Is is not transmitted to the primary side movable sheave 61 via the first connected member 74 and the first connecting portion 76.
In this case, the power from the input shaft Is is transmitted to the output shaft Os via the external gear 75 → second connecting portion 77 → fixed gear stage 6b → interaxial connecting gears 83 and 84 as shown in FIG. The

  According to the transmission transmission mechanism 6A configured as described above, the rotation directions of the input shaft Is and the output shaft Os can be matched.

  In the above example, the movable connecting member 79 is connected to the primary movable sheave 63 and moved integrally with the primary movable sheave 63. However, as shown in FIGS. A configuration as a transmission transmission mechanism 6 </ b> B connected to the secondary movable sheave 66 can also be adopted.

  FIGS. 8 and 9 are skeleton diagrams showing the configuration of the transmission mechanism 6B as a second modification as a schematic longitudinal sectional view. FIG. 8 shows the transmission ratio of the continuously variable transmission 6a as in FIG. FIG. 9 shows a state where the gear ratio is equal to or less than a predetermined gear ratio as an overdrive state, as in FIG.

  The transmission transmission mechanism 6B has a second shaft Ns added to the transmission transmission mechanism 6A shown in FIG. 7 and FIG. 8, and instead of the fixed gear stage 6b and the transmission switching unit 6c, the fixed gear stage 6bA is provided. The difference is that a transmission switching unit 6cA is provided.

In this case, in the continuously variable transmission 6a, the primary side shaft Ps is omitted, the primary side fixed sheave 62 is formed integrally with the input shaft Ps, and the primary side movable sheave 63 is splined to the input shaft Is. Thus, it can be displaced in the axial direction.
The secondary side shaft Ss in this case has a central portion in the axial orthogonal direction penetrating in the axial direction, and the second shaft Ns is inserted coaxially with the secondary side shaft Ss in the penetrated portion. The position of the secondary shaft Ss in the axial direction is fixed.

  In the fixed gear stage 6bA, an external gear 71 is arranged coaxially with the second shaft Ns, and a ring-shaped gear 72A made up of internal gears is provided in place of the ring-shaped gear 72 of both-tooth gears. In this case, the external gear 73 is provided so as to rotate integrally coaxially with the output shaft Os, and the internal teeth formed in the internal tooth portion 72Aa of the ring gear 72A are the second external tooth portion 71b of the external gear 71. And the external teeth in the external tooth portion 73 a of the external gear 73.

  The gear ratio of the fixed gear stage 6bA is also set to a gear ratio that realizes a gear ratio that is equal to or lower than a predetermined gear ratio corresponding to the overdrive state.

  The transmission switching part 6cA is located behind the secondary pulley 64, and rotates together with the second shaft Ns. The first connected member 74A, the first connecting part 76A, the second connecting part 77A, and the first A movable connecting member 79A having a connecting portion 78 that connects the connecting portion 76A and the second connecting portion 77A, an external gear 75A that is positioned behind the primary pulley 61 and rotates integrally with the input shaft Is; And a ring-shaped gear 85 by an internal gear.

  The first connected member 74A has an external tooth portion 74Aa on which a plurality of external teeth are formed, and the external gear 75A has an external tooth portion 75Aa on which a plurality of external teeth are formed.

The first connecting portion 76A has a substantially ring-shaped outer shape coaxial with the second shaft Ns, and has an inner tooth portion 76Aa in which a plurality of inner teeth are formed on the inner peripheral surface side. The first connecting portion 76 </ b> A is axially displaceable in conjunction with the secondary movable sheave 66 and rotates integrally with the secondary movable sheave 66 coaxially. In this example, the secondary-side movable sheave 66 is disposed at the front end portion and has a winding portion 66a having a conical surface as a winding surface of the winding member 67, and extends rearward from the outer peripheral portion of the winding portion 66a. The first connecting portion 76A has a rear end portion fixed to the outer peripheral surface at the front end portion of the extending portion 66b, and is interlocked with the secondary movable sheave 66. Thus, it can be displaced in the axial direction and is rotated integrally with the secondary movable sheave 66.
The inner tooth portion 76Aa in the first connecting portion 76A is located behind the rear end of the extending portion 66b.

The second connecting portion 77A has a substantially ring-shaped outer shape coaxial with the second shaft Ns, and has an outer tooth portion 77Aa formed with a plurality of external teeth on the front side and a plurality of internal teeth formed on the rear side. It has an internal tooth part 77Ab.
In this case, the connecting portion 78 is a substantially rod-like or substantially plate-like portion extending in the axial direction, the front end portion is connected to the first connecting portion 76A, and the rear end portion is connected to the second connecting portion 77A. Yes. The connecting portion 78 is fixed in a position around the axis, and connects the first connecting portion 76 and the second connecting portion 77 so as to be rotatable coaxially with the second shaft Ns.

  The external gear 75A has an external tooth part 75Aa in which a plurality of external teeth are formed, the ring gear 85 has an internal tooth part 85a in which a plurality of internal teeth are formed, and the ring gear 85 is The internal teeth in the internal tooth portion 85a are meshed with the external teeth in the external tooth portion 75Aa in the external gear 75A.

  In this example, at least the internal teeth 76Aa in the first connecting portion 76A and the external teeth 74a in the first connected member 74A, and the internal teeth 77Aa in the second connecting portion 77A and the first external teeth in the external gear 71. 71a absorbs the rotation difference between the first connecting portion 76A and the first connected member 74A and the rotation difference between the second connecting portion 77A and the external gear 71 (corresponding to the second connected member) at the time of meshing. Is configured as a synchromesh mechanism.

In the transmission mechanism 6B configured as described above, when the transmission ratio of the continuously variable transmission 6a is larger than the transmission ratio Rth (non-overdrive state), as shown in FIG. The inner teeth of the inner tooth portion 76Aa are engaged with the outer teeth of the outer tooth portion 74Aa of the first connected member 74A, and the power from the input shaft Is is continuously variable transmission 6a → the first connecting portion 76Aa → the first connected portion. It is transmitted to the second shaft Ns via the member 74A. The power transmitted to the second shaft Ns is transmitted to the output shaft Os via the reduction gear portion 6dA → the inter-shaft coupling gears 83 and 84.
On the other hand, in this case, the inner tooth portion 77Aa of the second connecting portion 77A is not meshed with any rotating element, and the power from the input shaft Is is not transmitted to the fixed gear stage 6bA.

When the transmission ratio of the continuously variable transmission 6a is equal to or less than the transmission ratio Rth, as shown in FIG. 9, the movable connecting member 79A is also displaced rearward along with the rearward movement of the secondary movable sheave 66, and the second connection The external teeth in the external tooth portion 77 </ b> Aa of the portion 77 </ b> A are meshed with the internal teeth in the internal tooth portion 85 a of the ring gear 85, and the internal teeth in the internal tooth portion 77 </ b> Ab are the external teeth in the first external tooth portion 71 a of the external gear 71. The power from the input shaft Is is transmitted to the fixed gear stage 6bA via the external gear 75A → the ring gear 85 → the external gear portion 77Aa of the second connecting portion 77A → the internal gear portion 77Ab.
On the other hand, the meshing state between the internal teeth in the internal tooth portion 76Aa of the first connecting portion 76A and the external teeth in the external tooth portion 74Aa of the first connected member 74A is eliminated, and the output of the continuously variable transmission 6a is the second shaft. Ns is not transmitted.

Even when the movable connecting member is connected to the secondary movable sheave 66 as described above, the power from the input shaft Is is supplied to the continuously variable transmission 6a according to the change in the gear ratio of the continuously variable transmission 6a. The first transmission state in which the power is transmitted to the output shaft Ns and the second transmission state in which the power is transmitted to the output shaft Ns through the fixed gear stage 6bA can be switched.
In addition, according to the structure shown in FIG.8 and FIG.9, the rotation direction of the input shaft Is and the output shaft Ns can be made to correspond.

<4. Summary of Embodiment>
As described above, the power transmission device according to the embodiment includes a primary pulley (61), a secondary pulley (64), and a winding member that is wound between the primary pulley and the secondary pulley. (Same as 37), a continuously variable transmission (same as 6a), a fixed gear stage (same as 6b or 6bA) in which the gear ratio is fixed, and a movable sheave (primary side movable sheave 63) of the primary pulley. Power from the input shaft (input shaft Is) is continuously variable by a movable connecting member (79 or 79A) that is axially displaceable in conjunction with the movable sheave (secondary movable sheave 66) of the secondary pulley. A transmission switching unit (6c or 6cA) for switching between a first transmission state that is transmitted to the output shaft (output shaft Os) via the transmission and a second transmission state that transmits the power via the fixed gear stage; It has.

Thus, when switching between the first transmission state and the second transmission state, it is not necessary to separately add an electromagnetic actuator or a hydraulic drive unit as a drive unit of the movable connecting member.
Therefore, cost reduction, size reduction, and weight reduction can be achieved for the power transmission device that enables switching between the power transmission state via the continuously variable transmission and the power transmission state via the fixed gear.

  In the power transmission device of the embodiment, the movable connecting member has a first connecting portion (76 or 76A) and a second connecting portion (77 or 77A) that are spaced apart in the axial direction. The transmission switching portion includes a first connected member (74 or 74A) having a first connected portion (external tooth portion 74a or 74Aa) connected to the first connecting portion in the first transmission state, and a second transmission. A second connected member (external gear 71) having a second connected part (first external tooth part 71a) connected to the second connecting part in a state, and the first connected part and the first connected part The part, the second connecting part, and the second connected part are configured as a synchromesh mechanism.

Thereby, the vibration and noise accompanying switching of the power transmission state can be reduced.
Therefore, it is possible to alleviate the discomfort of the occupant accompanying the switching of the power transmission state, and to improve the riding comfort.

  Furthermore, in the power transmission device of the embodiment, the movable connecting member is connected to the movable sheave of the primary pulley.

Thereby, unlike the case where the movable connecting member is connected to the movable sheave of the secondary pulley, the power of the input shaft is transmitted to the next shaft (the shaft coaxially arranged with the secondary pulley) in the second transmission state. For this purpose (ring-shaped gear 85) becomes unnecessary.
Therefore, the number of parts can be reduced, and the power transmission device can be reduced in cost and size.

  Furthermore, the power transmission device of the embodiment includes a reduction gear portion (6d or 6dA) that decelerates the output of the continuously variable transmission and transmits it to the output shaft, and the gear ratio of the fixed gear stage is that of the reduction gear portion. This is consistent with the reciprocal of the gear ratio.

Thus, in the second transmission state via the fixed gear stage, the primary pulley and the secondary pulley are rotated at the same rotational speed.
Therefore, it is possible to prevent the winding member from slipping due to the differential rotation of the primary pulley and the secondary pulley, and to suppress wear of each pulley and the accompanying heat generation, thereby increasing the length of the continuously variable transmission. Life expectancy is achieved.

  Further, in the power transmission device of the embodiment, when switching between the first transmission state and the second transmission state, a torque control unit (engine control unit 12) that reduces input torque from the engine (same as the above) provided to the vehicle to the input shaft. And a transmission mechanism control unit 13 or a transmission mechanism control unit 13).

Thereby, the vibration and noise accompanying switching of the power transmission state can be reduced.
Therefore, it is possible to alleviate the discomfort of the occupant accompanying the switching of the power transmission state, and to improve the riding comfort.

<5. Other variations>
In the above description, the example in which the synchromesh mechanism is applied to the transmission switching unit that switches between the first transmission state and the second transmission state has been described. However, it is not essential to apply the synchromesh mechanism to the transmission switching unit.

  Further, the fixed gear stage is not limited to a one-stage configuration, and may be configured to have a plurality of stages, and a plurality of gear stages can be switched.

  1 vehicle, 2 engine, 5 forward / reverse switching mechanism, CL forward / reverse switching clutch, BR forward / reverse switching brake, Is input shaft, Os output shaft, Ps primary shaft, Ss secondary shaft, Ts third shaft, Ns 1st Double shaft, 6, 6A, 6B Transmission mechanism, 6a Continuously variable transmission, 61 Primary pulley, 62 Primary fixed sheave, 63 Primary movable sheave, 64 Secondary pulley, 65 Secondary fixed sheave, 66 Two Secondary movable sheave, 67 winding member, 6b, 6bA fixed gear stage, 71 external gear (second connected member), 71a first external tooth portion (second connected portion), 72, 72A ring gear, 6c, 6cA Transmission switching part, 74, 74A First connected member, 75, 75A External gear, 76, 76A First connecting part, 77, 77A Second connecting part, 78 Connection portion, 79,79A movable coupling member, 85 ring gear, 6d, 6DA reduction gear unit, 12 engine control unit, 13 transmission mechanism control unit

Claims (5)

A power transmission device for a vehicle,
A continuously variable transmission having a primary pulley, a secondary pulley, and a winding member wound between the primary pulley and the secondary pulley;
A fixed gear stage with a fixed gear ratio;
Power from the input shaft is output to the output shaft via the continuously variable transmission by a movable connecting member that is displaceable in the axial direction in conjunction with the movable sheave of the primary pulley or the movable sheave of the secondary pulley. A transmission switching unit configured to switch between a first transmission state to be transmitted and a second transmission state to transmit the power via the fixed gear. The movable connecting member has a first connecting portion and a second connecting portion that are spaced apart in the axial direction,
The transmission switching unit
A first connected member having a first connected part connected to the first connecting part in the first transmission state; and a second connected part connected to the second connecting part in the second transmission state. The second connected member having the first connected portion and the first connected portion, and the second connected portion and the second connected portion are configured as a synchromesh mechanism. Power transmission device. The movable connecting member is
The power transmission device according to claim 1, wherein the power transmission device is connected to a movable sheave of the primary pulley. A reduction gear portion that decelerates the output of the continuously variable transmission and transmits it to the output shaft;
The power transmission device according to any one of claims 1 to 3, wherein a gear ratio of the fixed gear stage matches an inverse number of a gear ratio of the reduction gear portion. The power according to any one of claims 1 to 4, further comprising: a torque control unit that reduces an input torque from an engine included in the vehicle to the input shaft when switching between the first transmission state and the second transmission state. Transmission device.

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