JPS5917060A - Speed change gear for car - Google Patents

Abstract

PURPOSE:To simplify the construction of a speed change gear and make it with smaller size and weight by controlling a V-belt type stepless speed change gear and a reverse gear couple correlatively. CONSTITUTION:While a sleeve 52 is held at the shutting position as shown in the illustration and a specified oil pressure is being applied to oil pressure chambers 26, 36 of a stepless speed-change gear 18, power of the drive shaft 2 is transmitted to the driven shaft 4 through the stepless speed-change gear 18 to turn it in the same direction as the drive shaft 2. During this time, the car is in the position of running forward. In order to move the car backward, the V-belt 16 is put in slip condition as well as the sleeve 52 is shifted to the connective position, in which the sleeve 52 rides over spline shafts 48, 50.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission for driving a vehicle, and particularly to a transmission including a belt-driven continuously variable transmission.

The heald drive continuously variable transmission has a driving shaft and a driven shaft, respectively, and winds the drive pulley and driven pulley and KV belt, and increases or decreases the width of the grooves on both V-boots. It is used to change gears. ■To increase or decrease the width of the groove, a driving V pulley and a driven ■booley are used to move a pair of pulleys that cooperate with each other to form a V groove so that they cannot rotate relative to the driving shaft and the driven shaft, and cannot rotate relative to each other. The I-pulleys are configured so that they can be moved toward and away from each other, and each pair of I pulleys is moved toward and away from each other using hydraulic pressure or the like. In this belt-driven continuously variable transmission, the rotation of the drive shaft and the rotation of the driven shaft are in the same direction, so by attaching external gear wheels to each of these shafts and meshing them with each other, the direction of rotation of both shafts can be adjusted. The reverse is possible, resulting in a simple reverse gear train.

Therefore, by combining the heald drive continuously variable transmission with a reverse gear train consisting of a pair of external gears as described above, that is, a reverse gear pair, a simple transmission for driving a vehicle should be obtained.

The present invention was completed based on such an idea, and therefore, an object of the present invention is to provide a vehicle drive transmission that has a simple configuration, is small in size, and can be manufactured in light weight. . In order to achieve this object, the transmission device according to the present invention includes a drive shaft and a driven shaft, a belt drive continuously variable transmission and a reverse gear pair provided in parallel between the two shafts, and a continuously variable transmission and a reverse gear pair. The transmission is configured to include a control device that controls the transmission and the reverse gear pair. As the heald drive continuously variable transmission, the one described above can be used, and the reverse gear pair is composed of a pair of external gear wheels that are provided concentrically with the drive shaft and the driven shaft so as to be able to mesh with each other. be done. One of these external gears is fixed to either one of the drive shaft and the driven shaft, and the other is rotatably but axially immovably attached to the remaining one of the drive shaft and the driven shaft, and is connected to that shaft as appropriate. A state in which power can be transmitted and a state in which power cannot be transmitted are determined by whether the gear is engaged and disengaged by a clutch, or whether it is attached to the shaft so as to be movable in the axial direction and non-rotatable and engaged with and disengaged from the fixed gear. be made available selectively. In addition, the control device sets the vehicle forward state in which the IJ hearth gear pair is in a power transmittable state and the continuously variable transmission is in a power transmittable state, and the reverse gear pair is in a power transmittable state and the continuously variable transmission is in a power transmittable state. The vehicle is configured to be able to selectively take the vehicle backward state. In order to make the continuously variable transmission unable to transmit power, it is necessary to widen the V groove widths of both the driving V pulley and the driven V pulley to put the V belt in a slip state, or to connect the drive shaft to the input section and the driving V pulley.
Various means can be adopted, such as dividing the pulley support section into a pulley support section, disposing a clutch between the two, and disengaging the clutch.

In the transmission configured as described above, the reverse gear train does not require an intermediate shaft, and can be configured extremely simply and compactly. Conventional gear-type transmissions are generally of a parallel three-shaft type that includes an intermediate shaft that supports an idler gear, and automatic transmissions that include a pair of planetary gears and a wet multi-disc clutch (braking) are common. Compared to conventional transmission systems, the reverse gear train of the transmission according to the present invention is extremely simple, and the entire transmission can be manufactured to be simple, compact, and lightweight.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, 2 is a driving shaft and 4 is a driven shaft. Both shafts are arranged parallel to each other and are rotatably supported by a transmission casing (not shown) via bearings 6, respectively. The drive shaft 2 is connected to an output shaft 10 of the engine via a main clutch 8, and is rotationally driven by the engine.

The drive shaft 2 and the driven shaft 4 each have a drive V pulley 12.
and a driven V-pulley 14 are attached, and a V-belt 16 is wound between the two, and these constitute a belt-driven continuously variable transmission i18. The drive V-pulley 12 includes a fixed pulley 20 fixed to the drive shaft 2 and a movable pulley 22 attached to the drive shaft 2 so as to be movable in the axial direction but not rotatable. A housing 24 is further fixed to the drive shaft 2, and a movable pulley 22 is slidably and fluid-tightly fitted inside the housing 24, and a hydraulic chamber 26 is formed between the two. That is, the movable pulley 22 and the housing 24 constitute a hydraulic cylinder that moves the movable pulley 22 itself in the axial direction. The end surfaces of the fixed pulley 20 and the movable pulley 22 facing lr are made into conical surfaces with a large apex angle, and as a result, a V groove 28 is formed between them, and the width of this V groove 28 is larger than that of the movable pulley 22. can be changed by being moved axially.

Driven ■ Boo'J 14 also includes a fixed pulley 30 and a movable pulley 32 in the same way as the drive pulley 12. The movable pulley 32 cooperates with the housing 34 to form a hydraulic chamber 36, and the movable pulley 32 cooperates with the fixed pulley 20 to form a hydraulic chamber 36. A groove 38 whose width is variable is formed.

Hydraulic oil is supplied to or discharged from the hydraulic chambers 26 and 36 through oil passages formed at the centers of the drive shaft 2 and driven shaft 4, respectively. The pressure receiving area of the movable pulley 22 is approximately twice that of the movable pulley 32, and by actively increasing or decreasing the amount of hydraulic fluid in the hydraulic chamber 26, the width of the groove 28 can be changed. Following this, the movable pulley 32 moves in the axial direction while keeping the tension of the belt 16 at a predetermined value.
The gear ratio, that is, the value obtained by dividing the rotational speed of the driven shaft 4 by the rotational speed of the drive shaft 2, can be changed steplessly. Supply and discharge of hydraulic oil to and from the hydraulic chambers 26 and 36 is performed by a control device 39.

A reverse gear pair 40 is provided between the drive 11iff12 and the driven shaft 4 in parallel with the continuously variable transmission 18. This reverse gear pair 40 is comprised of a second external gear wheel 44 which is provided in a sealed manner on the drive shaft 2 and fixed to the driven shaft 4. Both of the external gear wheels 42 and 44 are provided concentrically with the drive #J2 and the driven i11[1+4, respectively, and are always meshed with each other. A dog clutch 46 is provided between the first external gear 42 and the drive shaft 2. The dog clutch 46 is connected to the first external gear 42
The drive shaft 2 includes spline shafts 48 and 50 and a sleeve 52, which are respectively provided integrally with the drive shaft 2. The sleeve 52 is controlled by the control device 39 to be in a blocking position in which it engages only with the spline shaft 50 and in a blocking position in which it engages only with the spline shaft 4.
8 and a connecting position in which it engages both the splined shaft 50 and the splined shaft 50.

The driven shaft 40 rotations are caused by a gear 54 fixed to the driven shaft 4.
and a gear 58 fixed to the shaft 56 through a retraction gear pair 60 . The rotation of this shaft 56 is further transmitted from a gear 62 fixed to the shaft 56 to a ring gear 66 of a differential device 64, and further transmitted to a ring gear 66 of a differential device 64.
The signals are transmitted from l168 and 70 to the wheels to make the vehicle run. Since the differential device 64 is well known, a detailed description thereof will be omitted.

In the transmission configured as described above, the control device 3
9 holds the sleeve 52 in the cutoff position shown in FIG. is transmitted to the driven shaft 4 by the machine 18, and the driven shaft 4
is rotated in the same direction as the drive shaft 2. The state of the control device 39 at this time is referred to as the vehicle forward state. In addition, the rotational speed of the drive shaft 4 is determined by changing the width of the grooves 28 and 38 of the driving pulley 12 and the driven V-pulley 14, so that the optimum gear ratio can be determined for the ever-changing running conditions of the vehicle. controlled as obtained. This allows the vehicle to move forward at a desired speed while keeping the engine speed within a certain range with the highest thermal efficiency, improving fuel efficiency.

Conversely, when it is necessary to move the vehicle backwards, the control device 39 lowers the oil pressure in the hydraulic chambers 26 and 36 to put the V-bell 16 into a slip state, and
Sleeve 52 is moved to a connected position spanning both spline shafts 48 and 500. Control device 3 at this time
9 is the vehicle backward state, the power of the drive shaft 2 is transmitted to the driven shaft 4 via the reverse gear pair 40, the driven shaft 4 is rotated in the opposite direction to the drive shaft 2, and the vehicle is moved backwards. to retreat.

FIG. 2 shows another embodiment of the invention. In this embodiment, the drive shaft 80 is connected to the input section 80A and the drive V-boot support section 8.
It is divided into two parts, 0B and 0B, and these two parts are connected and disconnected by a dog clutch 82. The dog clutch 82 includes a spline shaft 84 provided integrally with the human power section 80A, and a drive V pulley support section 80B.
It consists of a spline shaft 86 and a sleeve 88, which are provided integrally with the spline shaft 86 and the sleeve 88. Sleeve 88 is a control device 90
a blocking position in which the spline shaft 84 is engaged only by the
It is adapted to be moved between a connecting position in which it straddles and engages both spline shafts 84 and 86. The sleeve 88 also connects the first external gear 9 of the reverse gear pair 92.
The dog clutch 82 can also be engaged with a spline @ 96 provided integrally with the drive shaft 80, and the dog clutch 82 also serves as a clutch for engaging and disengaging the input wheel 94 of the drive shaft 80. There is. A belt-driven continuously variable transmission 98 is provided in parallel with the reverse gear pair 92, and this continuously variable transmission 98 includes a driving V pulley 100, a P1 driving V pulley 102, and a driving V pulley 102. This is the same as in the previous embodiment.

The supply and discharge of hydraulic oil to the hydraulic chambers 106 and 108 of the driving (1) pulley 100 and the driven V-pulley (102) is controlled by a control device 90. Since the parts other than the two sets are the same as those in the previous embodiment, detailed explanation will be omitted.

In this embodiment, the sleeve 8 is controlled by the control device 90.
8 is in a connected state in which it engages across both spline shafts 84 and 86, and the hydraulic chambers 106 and 10
By applying a predetermined hydraulic pressure to the continuously variable transmission 98, the continuously variable transmission 98 is brought into a state capable of transmitting power. On the other hand, the reverse gear pair 92 is unable to transmit power because the sleeve 88 is separated from the spline shaft 96, and the driven shaft 110 is eventually rotated in the same direction as the drive shaft 80.

The state of the control device 90 at this time is the vehicle forward state.

On the other hand, if the sleeve 88 is moved to a position where it straddles and engages both spline shafts 84 and 96, the drive shaft 88
The drive V-pulley support part 80B is disconnected from the input part 80A, the continuously variable transmission 98 becomes unable to transmit power, the reverse gear pair 92 becomes capable of transmitting power, and the driven shaft 110 is in the opposite direction to the drive shaft 80. It will be rotated in the direction.

The state of the control device 90 at this time is the vehicle backward state.

Although the above two embodiments have been described in detail, the present invention can be implemented in various modifications and improvements based on the knowledge of those skilled in the art without departing from the scope of the claims. It is.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a transmission which is one embodiment of the present invention, and Fig. 2 is a schematic diagram of another embodiment of the present invention.8: Main launch lO: Engine output shaft 12.100: Drive ■Pulley 14.102: Driven pulley 16.104: V-belt 18.98: Belt drive continuously variable transmission 20.30: Fixed pulley 22.32: Movable pulley 24.34: Housing 26.36, 106, 1 (18 -Hydraulic chamber 28.38:V
Groove 39, 90: Control device 40. 92: Reverse gear pair 42. 94: First external tooth gear 44: Second external gear wheel 46. 82: Dog clutch 48. 50, 84, 86, 96 Nispline shaft 52.
88 Ni sleeve 80A: Input section 80B-Drive V-boot support section Applicant Toyota Motor Corporation

Claims (1)

[Scope of Claims] A drive shaft rotated by a prime mover of a vehicle; a driven shaft rotated by power from the drive shaft; It consists of a pair of pulleys that are mounted so that they cannot rotate relative to each other, and a V groove is formed between the pair of pulleys, and when the pair of pulleys are moved toward and away from each other in the axial direction, the V groove is formed. A belt-driven continuously variable transmission includes a heald that transmits the power of the drive shaft to the driven shaft and rotates the driven shaft in the same direction as the drive shaft; Concentrically with the drive shaft,
and consists of a pair of external gears disposed so as to be able to mesh with each other, one of the gears is fixed to either one of the two shafts, and the other gear is meshed with and disengaged from the one gear, or a pair of reverse gears that can selectively be in a power transmittable state and a power transmittable state by being engaged with and disengaged from the other one of the gears by a flanch; a control device that can selectively take a vehicle forward state in which the vehicle is in a power transmittable state, and a vehicle backward state in which the reverse gear pair is in a power transmittable state and the continuously variable transmission is in a power transmittable state. A vehicle drive transmission characterized by: