JPS60184758A - Stepless transmission - Google Patents

Abstract

PURPOSE:To make large the range of variation in the ratio of the rotational speeds of the engine side drive shaft and the wheel side driven shaft, by using a variable pulley and a pulley regulating mechanism. CONSTITUTION:A first drive belt 11a is stretched between a first variable pulley 5 and a third variable pulley 25, and a fourth variable pulley 27 is fitted onto an intermediate shaft 26. The right side plate 25a of the third variable pulley 25 and the left side plate 27b of the fourth pulley 27 are fitted onto a coaxial shaft 28 which is coaxially arranged with the intermediate shaft 26. The coaxial shaft 28 is splinedly engaged with the intermediate shaft 26 and is coupled with the piston section 29a of a cylinder mechanism 29 constituting a pulley adjusting mechanism D which increases the effective diameter of either one of the third variable pulley 25 and the fourth variable pulley 27, and decreases the diameter of the other one, and which is controlled by a control unit 9, thereby the width of variation in the ratio of the rotational speeds of the drive and driven shafts, may be made large.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a continuously variable transmission (Continuous Vessel transmission).
locityTransmission; hereinafter referred to as "cVTJ").

In a conventional continuously variable transmission (CVT), as shown in FIG. 1, a drive shaft 4 is connected to an output shaft 2 of a vehicle engine 1 via a long travel damper 3.
A first variable pulley 5 whose effective radius is variable is mounted on the first variable pulley 5, and a cylinder mechanism 6 constituting the pulley adjustment mechanism and an oil pump are attached to the first variable boolean IJ5. (Variable displacement vane pump) 7 is connected.

That is, the first variable pulley 5 is configured as a drive pulley of the pulley mechanism P.

The left side plate 5b of the first variable pulley 5 is fixed to the drive shaft 4, and the right side plate 5a of the first variable pulley 5 is spline-engaged with the drive shaft 4. 6 is connected to the piston portion 6a.

Hydraulic oil is supplied to the working chamber 6b of the shilling mechanism 6 from a hydraulic control device 8 that constitutes a pulley adjustment mechanism, and the amount of the hydraulic oil supplied is controlled by a Huntroll unit (as a control mechanism). It is controlled by a control signal sent from the computer) 9 to the hydraulic control device 8.

Further, a drive belt 11 is mounted on the first variable pulley 5 and the second variable boob IJ10, and the second variable pulley 10 is mounted on a driven shaft (driven shaft) 12.

The left side plate 10b of the second variable pulley 10 is connected to the driven shaft 1
The right side plate 10a of the second variable pulley 10 is fixed to the driven shaft 12.

That is, the second variable pulley 10 is configured as a driven pulley of the pulley mechanism P.

The driven shaft 12 is connected to a starting clutch 14 . Gear 15 forward/forward switching clutch 16. Axis 17. Gear 18. Differential gear mechanism 1
9 and a wheel drive shaft 20 .

Note that the reference numeral 13a in FIG. 1 indicates a spring, and the reference numeral 22 indicates a bearing.

Conventional continuously variable transmissions are constructed in a similar manner, so that they can continuously change the gear ratio and supply hydraulic oil to the working chamber 61 of the cylinder mechanism 6 that constitutes the pulley adjustment mechanism. If not, spring-type response mechanism 1
3, the left side plate 10b of the second variable pulley 10 is driven to the right in FIG.
As the effective radius of the variable pulley 10 becomes larger, the effective radius of the first variable pulley 10 becomes smaller.

As a result, the gear ratio of the pulley mechanism P increases, and the driven shaft 12 is rotated at a large deceleration.

Furthermore, when supplying hydraulic oil to the working chamber 61 of the cylinder mechanism 6 that constitutes the pulley adjustment mechanism, the right side plate 5a of the first variable pulley 5 is driven to the left in FIG. , the effective radius of the first variable pulley 5 becomes larger, and the effective radius of the second variable pulley 10 becomes smaller.

As a result, the gear ratio of the pulley mechanism P becomes smaller, and the driven shaft 12 is driven at an increased speed.

However, in the conventional continuously variable transmission, the ratio (speed ratio) between the rotation speed Ni of the drive shaft 4 and the rotation speed No of the driven shaft 12 in a large deceleration state (speed ratio) tN i / No1m1n and the speed change in a speed increase state Ratio I N i / N ol+na
The problem is that the ratio (width of the gear ratio) to , the cost will be high.

On the other hand, it is conceivable to make the entire device large-sized, but this would require a large amount of space, reduce transmission efficiency, and be difficult to mount on a vehicle.

The present invention aims to solve such problems, and is capable of increasing the range of change in the ratio of the rotation speed of the engine-side drive shaft to the rotation speed of the wheel-side driven shaft.
The purpose is to provide a continuously variable transmission.

For this reason, the continuously variable transmission device of the present invention includes a first variable pulley attached to the drive shaft on the encoder side and a second variable pulley attached to the driven shaft on the wheel side, so as to control the driving force of the drive shaft. An intermediate shaft for transmitting power to the driven shaft is provided, and the intermediate shaft has a first variable
A third variable pulley to which a drive belt is mounted, and a fourth variable pulley to which a second drive belt is mounted between the second variable pulley and the third variable pulley are provided. One side plate of the variable pulley and one side plate of the fourth variable pulley are interlocked to expand the effective radius of one of the third variable pulley and the fourth variable pulley and to reduce the effective radius of the other. The present invention is characterized in that it is provided with a pulley adjustment mechanism that adjusts the pulley adjustment mechanism so that the engine speed decreases, and a control mechanism that controls the pulley adjustment mechanism according to the state of the engine.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.
2 to 8 show a continuously variable transmission device as a first embodiment of the present invention, FIG. 2 is an overall configuration diagram thereof, FIG. 3 is a schematic diagram showing the state of its drive belt, and FIG. 4 is a schematic diagram showing a modified example of the response mechanism, Figures 5 to 8 are graphs for explaining its operation, and Figure 9 is an overall diagram showing a continuously variable transmission as a second embodiment of the present invention. FIG.

In addition, in FIGS. 2 to 9, the same reference numerals as in FIG. 1 indicate almost the same parts. As shown in FIGS. A drive shaft 4 is connected to the output shaft 2 via a long travel damper 3 and a clutch 23.
A first variable pulley 5 is attached to the drive shaft 4, and a spring type response mechanism 24 and an oil pump (variable capacity vane pump) 7 are connected to the first variable pulley 5.

That is, the first variable boob 95 is configured as a driven pulley of a first stage pulley (number P).

The right side plate 5a of the first variable pulley 5 is fixed to the drive shaft 4, the left side plate 5b of the first variable pulley 5 is spline engaged with the drive shaft 4, and further has a spring type response mechanism. It is urged to the right in FIG. 2 by a spring 24a of 24.

A first drive bell) is mounted on the first variable pulley 5 and the third variable pulley 25, and the third variable pulley 25 is mounted on an intermediate shaft 26.

Further, a fourth variable boob 927 is attached to the intermediate shaft 26, and the left side plate 25b of the third variable pulley 25 and the right side plate 27a of the fourth variable pulley 27 are connected to the intermediate shaft 26.
is fixed.

Then, the right side plate 25a of the third variable pulley 25 and the fourth
The left side plate 27b of the variable pulley 27 is fixed to a concentric shaft 28 coaxially arranged with the intermediate shaft 26.

This concentric shaft 28 is spline-engaged with the intermediate shaft 26, and is further connected to a piston portion 29a of a sillage mechanism 29 that constitutes a pulley adjustment mechanism.

The pulley adjustment mechanism includes a third variable pulley 25 and a fourth variable pulley 25.
The effective radius of one of the variable pulleys 27 is expanded, and at the same time,
It is configured to reduce the effective radius of the pond.

Hydraulic oil is supplied to the working chamber 29b of the silling mechanism 29 through an oil passage 30 formed in the intermediate shaft 26 from the hydraulic control device 8 constituting the boob adjustment mechanism, and its operation The amount of oil supplied is controlled by a control signal sent from a control unit (computer) 9 as a control mechanism to the hydraulic III control device 8.

This mount roll unit 9 includes a throttle opening sensor 31 for detecting the load of the ennon 1. Engine speed sensor 32 for detecting engine speed. Detection signals are supplied from a vehicle speed sensor 33 that detects vehicle speed and an accelerator depression speed sensor 34 that detects accelerator depression speed.

In this way, the third variable pulley 25 and the fourth variable pulley 27 are configured as drive-side pulleys of the first-stage pulley mechanism P1 and the second-stage pulley mechanism P2, and the concentric shaft 28 is , is always biased to the right in FIG. 2 by a spring 29c.

Note that the cylinder mechanism 29 may be provided on the left side of the intermediate shaft 26 instead of on the right side. In this case, the concentric shaft 28 is always biased toward the left (=) in FIG. 2 by the spring 29c. be done.

Further, a second drive bell (41b) is mounted on the fourth variable pulley 27 and the second variable pulley 10, and the second variable pulley 10 is mounted on the driven shaft (driven shaft) 12. has been done. - the right-hand side plate 10a of the second variable pulley is in spline engagement with the driven shaft 2) and is further connected to a spring-type response mechanism 13, while the second variable pulley 1
The left side plate 10b of No. 0 is fixed to the driven shaft 12.

That is, the second variable pulley 10 is configured as a driven pulley of the second stage pulley mechanism P2.

The driven shaft 12 is connected to a starting clutch 14 . Gear 159 Forward/forward switching clutch 16. Axis 17. Gear 18. Differential gear mechanism 1
9 and a wheel drive shaft 20 .

Note that the reference numeral 13a in FIG. 2 indicates a spring, and the reference numeral 22 indicates a bearing.

Since the continuously variable transmission device according to the first embodiment of the present invention is configured as described above, the gear ratio can be changed continuously, and the silling mechanism 2 constituting the pulley adjustment mechanism
When hydraulic oil is not supplied to the working chamber 291] of the third variable pulley 25, the spring 29c drives the concentric shaft 28 to the right in FIG. and the left side plate 2 of the fourth variable pulley 27
7a is driven to the right in FIG. 2, the effective radius of the third variable boob 925 becomes smaller, and the effective radius of the fourth variable pulley 27 becomes larger.

As a result, the effective radius of the first variable pulley 5 becomes larger than normal, and the effective radius of the second variable pulley 10 becomes smaller.

This causes the first and second drive bells) lla, ll
3, the gear ratio of the first stage pulley mechanism P1 becomes smaller, the intermediate shaft 26 is driven at an increased speed compared to the drive shaft 4, and the second stage Pulley mechanism P
2 gear ratio also becomes smaller, driven shaft 12 or intermediate shaft 2G
It is driven at increased speed compared to.

That is, the first stage and second stage pulley mechanisms Pl +
The combined total chamber speed ratio of P2 becomes smaller and becomes the minimum total chamber speed ratio iNi/NoJ+n, and the driven shaft 12 is driven at an increased speed compared to the drive shaft 4.

Furthermore, a sillage mechanism 29 that constitutes a pulley adjustment mechanism
When supplying hydraulic oil to the working chamber 29b of the concentric shaft 2
8 is driven to the left in FIG. 2, that is, the right side plate 25a of the third variable pulley 25 and the left side plate 27b of the fourth variable pulley 27 are driven to the left in FIG. Therefore, the effective radius of the third variable pulley 25 becomes thicker, and the effective radius of the fourth variable pulley 27 becomes smaller.

Accordingly, the effective radius of the variable pulley 5 of @1 becomes smaller, and the effective radius of the second variable pulley 10 becomes larger.

1), the first and second drive belts lla, I
lb is in the state shown by the solid line in FIG. 3, the gear ratio of the mechanism P1 of the first stage pulley becomes large, the intermediate shaft 26 is driven at a reduced speed compared to the drive shaft 4, and the second stage pulley is driven at a reduced speed compared to the drive shaft 4. The gear ratio of the stage pulley mechanism P2 is also increased, and the driven shaft 12 or the intermediate shaft 2
It is driven at a reduced speed compared to 6.

That is, the first stage and second stage pulley mechanisms p, ,
1? The combined total chamber speed ratio of 2 becomes extraordinary and becomes the maximum total chamber speed ratio iN i/Nolmax, and the driven shaft 12
is driven at a reduced speed compared to the drive shaft 4.

In this way, the ratio (i.e., range width) between the minimum total speed ratio IN i/No1m1n and the maximum total indoor speed ratio IN i/Nolmax is, for example, 4 to 10, and as shown in FIG. The gear ratio iNi/Nol can be increased with respect to the axial displacement X of the drive pulley due to pulley adjustment (variation), and a change width twice as large as that of the conventional method can be achieved.

That is, as shown in FIG. 7, in this device, the gear ratio I
Where Ni/Not is large, that is, speed ratio iNo
When /Nii is small, the transfer efficiency η increases by 2,
This can be achieved by constructing an efficient continuously variable transmission.

In addition, as shown in FIG. 4, each response mechanism may be configured as a hydraulic sillage mechanism 13', 24', in which case,! The left side plate 51 of the variable pulley 5 of 181 is connected to the piston portion 13'a of this sill mechanism 13', and the right side plate 10a of the second variable boo 1710 is connected to the piston portion 24'a of this sill mechanism 24'. connected to.

And to each working chamber 13'I], 24'I),
Pressure oil whose pressure is controlled is supplied from a hydraulic circuit C, and this hydraulic circuit C includes a spool valve 35°, a constant hydraulic pressure source 3G, orifices 37, 38. A solenoid valve 39 is provided.

The position of the spool valve 35 is adjusted by the force received from the hydraulic pressure supplied to the land 35a and the force exerted by the spring 40, and the position of the spool valve 35 is adjusted in each working chamber 1.3'l).

The hydraulic pressure supplied to 24'b is determined.

As a result, the solenoid valve 39 receives a control signal from the load roll unit 9, and the regulated pressure oil is supplied to the spool valve 35 by duty control as shown in FIG. As shown in FIG. 6, each working chamber contains 1.3'l of pressurized oil whose pressure is appropriately regulated.

24'l].

In this way, the pressure oil supplied to each of the working chambers 13'l) and 24'+1 allows the first and second variable pulleys 5110 to be pushed in accordance with the gear ratio (1/speed ratio) and transmission torque. As a result, the transmission efficiency η increases in the 1) direction, and the hydraulic pressure supplied to the first nf variable pulley 5 is changed to the second nf variable pulley 5 according to the speed ratio, as shown in Fig. Since the oil pressure can be made larger or smaller than the oil pressure supplied to the variable pulley 10, rational pressing oil pressure control can be performed with one control system.

As shown in FIG. 9, in the second embodiment of the present invention, the rotation center of the drive shaft 4 and the rotation center of the driven shaft 12 are arranged on the same line, and the configuration of the pond is similar to that of the first embodiment. It is almost the same.

Since the second embodiment is configured in this way, it is possible to make the entire device more compact by making the space smaller than the first embodiment, and to improve the in-vehicle compatibility. It can also contribute to weight reduction.

Furthermore, processing of the transmission case is made easier as in the first embodiment, and substantially the same effects as in the first embodiment can be obtained.

As detailed above, according to the continuously variable transmission of the present invention,
a first variable pulley attached to the engine side drive shaft;
A second variable pulley attached to the wheel-side driven shaft is provided, and an intermediate shaft is provided for transmitting the driving force of the drive shaft to the driven shaft, and the first variable pulley is attached to the intermediate shaft. The third i is mounted with the first drive belt t in one ift of
T]' The second variable pulley is connected between the variable pulley and the second variable pulley.
A variable pulley of VJ4 on which a drive belt is mounted is provided, and one 11tll plate of the third variable pulley and one side plate of the fourth variable pulley are interlocked to drive the third variable pulley. and a pulley adjustment mechanism that adjusts the fourth variable pulley to expand one effective radius and reduce the other effective radius, and a control mechanism that controls the pulley adjustment mechanism according to the engine state. The following effects and advantages can be obtained with a simple configuration in which the following is provided.

(1) The range of change in the ratio of the rotation speed of the engine-side drive shaft to the same number of wheel-side driven shafts is taken to be large.

(2) Referring to item 1 above, even when combined with a low-displacement engine, the necessary torque can be obtained without using a torque converter or differential speed reduction mechanism.

(3) From the above item 2, reduce the cost by one degree.

(4) Transmission efficiency at large gear ratios increases by 2', improving fuel efficiency.

(5) Durability is improved if the excessive portion of the gear ratio is not used.

C6) Both the third variable pulley and the fourth variable pulley can be driven with one pulley adjustment mechanism.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing a conventional continuously variable transmission.
@Figures 2 to 8 show a continuously variable transmission as a first embodiment of the present invention. Figure 2 is its overall configuration, Figure 3 is a schematic diagram showing the state of its drive belt, and Figure 4. is a schematic diagram showing a modified example of the response mechanism, FIGS. 5 to 8 are graphs for explaining the action, and FIG.
FIG. 1 is an overall configuration diagram showing a continuously variable transmission as an example. 1. Engine, 2. Output shaft, 3. Long travel gunpa, 4. Drive shaft, 5. First variable pulley, 5
a...Right side plate, 51]...Left side plate, 7...Oil pump, 8...Hydraulic control device constituting the pulley adjustment mechanism,
9... Control unit (computer) as a control mechanism, 10... Second variable pulley, 1()a... Right side plate, 101)... Left side plate, lla... First drive belt, 111]. - Second drive belt, 12... Driven shaft (driven shaft), 13... Spring type response mechanism, 13
a...Spring, 13'...Hydraulic sillage mechanism as a response mechanism, 13'a...Piston part, i3'l]
... Working chamber, 13'c... Spring, 14... Starting clutch 7, 15... Gear, 16... Forward/forward switching clutch,
17...shaft, 18...gear, 19...differential gear mechanism, 2
0...Wheel drive shaft, 21...Wheel, 22...Bearing, 23
...Clutch, 24...Spring type response mechanism, 24a
・・Spring, 24′ ・・Hydraulic sillage mechanism as a response mechanism, 24′a・・Piston part, 24′ll・
- Working chamber, 24'c...Spring, 25...Third variable pulley, 25a...Right side plate, 25I)...Left side plate, 26...Intermediate shaft, 27...Fourth variable pulley, 27a
...Right side plate, 27b...Left side plate, 28...Concentric shaft,
29...Cylinder mechanism configuring the pulley adjustment mechanism, 29
a...Piston part, 291]...Working chamber, 29c...Spring, 30...Oil passage, 31...Throttle opening sensor, 32...Engine number sensor, 33...Vehicle speed sensor, 34...Accelerator Depressing speed sensor, 35... Spool valve, 35a... Land, 36... Constant oil pressure source,
37° 38... Orifice, 39... Solenoid valve, 40...
Spring, C...Hydraulic circuit, D...Boori tone'AIm
structure, Pl...1st stage pulley mechanism, P2...2nd stage booby mechanism. Agent Patent Attorney Yoshihiko Iinuma Figure 1 21 t+ Figure 2 Figure 3 Figure 7 Figure 8

Claims (1)

[Claims] a first variable pulley attached to the engine side drive shaft;
A second variable pulley attached to the wheel-side driven shaft is provided, and an intermediate shaft is provided for transmitting the driving force of the drive shaft to the driven shaft, and the intermediate shaft has the first variable pulley and the second variable pulley attached to the driven shaft on the wheel side. A third variable pulley on which the first drive belt is mounted between, and a variable pulley @4 on which the second drive belt is mounted between the second variable pulley. 2. One side plate of the third variable pulley and one side plate of the 71st variable pulley are interlocked to enlarge the effective radius of one of the third variable pulley and the fourth variable pulley. and a control mechanism that controls the pulley adjustment mechanism in accordance with the state of the engine. .