JPH01153368A - Method of controlling brake in continuously variable transmission - Google Patents

Abstract

PURPOSE:To prolong the use life of a brake means by delivering various kinds of detection signal indicating a vehicle drive condition to a control section so that the control section actuates a brake means only when a detection signal indicating a specific shift lever position is received. CONSTITUTION:A control section 82 receives various kinds of detection signals indicating a vehicle drive condition, and controls actuating a brake means only when a detection signal indicating a specific shift lever position L is received. That is, when the control section 82 receives a detection signal indicating the shift lever position L, the control section 82 controls the operation of the brake means so as to prevent unnecessary braking force from being held, and accordingly, a braking force is effectively held when it is required. With this arrangement, it is possible to prolong the use life of the brake means, thereby it is possible to enhance the safety of the vehicle.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brake control method for a continuously variable transmission.
In particular, by inputting various detection signals of vehicle driving conditions to the control unit,
Continuously variable shifting controls the operation of the braking device based on the shift lever position detection signal, prevents unnecessary braking force from being held, effectively maintains braking force only when needed, and improves vehicle safety. This article relates to a brake control method for an aircraft.

[Conventional technology]

In a vehicle, a transmission is interposed between an internal combustion engine and drive wheels. This transmission changes the driving force and running speed of the drive wheels in accordance with the widely varying running conditions of the vehicle, thereby allowing the internal combustion engine to fully demonstrate its performance. The transmission includes a fixed pulley part fixed to the rotating shaft and a movable pulley part attached to the rotating shaft so as to be able to approach and separate from the fixed pulley part. There is a continuously variable transmission that transmits power by increasing or decreasing the rotation radius of a belt wrapped around a pulley by increasing or decreasing the width of the groove, thereby changing the speed ratio (belt ratio). Examples of this continuously variable transmission include, for example, JP-A-57-186656, JP-A-59-43249, and JP-A-59-77.
It is disclosed in Japanese Patent Application Laid-open No. 159 and Japanese Patent Application Laid-open No. 61-233256.

[Problem that the invention seeks to solve]

By the way, in a conventional brake control method for a continuously variable transmission, a hydraulic clutch is controlled by electronic control, and the clutch pressure of the hydraulic clutch is controlled in a neutral mode or a hold mode while the vehicle is stopped.

In neutral mode, the shift lever
The hydraulic clutch is in the N or P position, and the hydraulic clutch is completely off and the clutch pressure is zero.

In addition, in the hold mode, the shift lever is in the D, P, or P position, and the hydraulic clutch is activated slightly to increase the clutch pressure to 3 to 4 kg/crA, causing the hydraulic clutch to slip to reduce a small amount of creep. It is occurring. In this hold mode, shift the shift lever position to D.
Alternatively, when the vehicle is in the L position and the vehicle is brought to a stop and then restarted, it is necessary to switch from the brake pedal to the accelerator pedal. During this switching operation, the control mode switches from hold mode to start mode. It is something.

As a result, when stopping and restarting on an uphill slope,
When switching from a hold mode, in which engine torque is not transmitted, to a start mode, in which engine torque is transmitted, there is a concern that the vehicle may run backwards before it starts, and an improvement has been desired.

Further, in order to prevent the above-mentioned problems, there is a method of using a handbrake, but there are disadvantages in that operating the handbrake is troublesome, requires skill, and is not easy to use.

Further, in order to prevent the above-mentioned problems, the applicant of the present invention provided the continuously variable transmission with a brake means, and applied the brake means to the continuously variable transmission when the vehicle speed was maintained at O for 1.5 seconds and the brake switch was turned on. However, on the same day, they filed an application for a brake control method for a continuously variable transmission in which a solenoid valve for retaining braking force is controlled to be closed when the accelerator pedal switch satisfies the off condition.

However, in this brake control method, by controlling the brake means to operate even when stopping on a flat road, unnecessary braking force is maintained and the brake means is overworked. This has the disadvantage of shortening the service life and being economically disadvantageous.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, in order to eliminate the above-mentioned disadvantages, an object of the present invention is to provide a control section that inputs various detection signals of vehicle driving conditions, and also provide a braking means for decelerating or stopping the vehicle using braking force. By inputting various detection signals of the operating state and controlling the operation of the brake means by the control section only when a detection signal of a specific shift lever position is input, the operation of the brake means is controlled by the detection signal of the shift lever position. It is possible to prevent unnecessary retention of braking force and effectively retain braking force only when necessary, thereby extending the service life of the braking means, which is economically advantageous, and improves vehicle performance. The object of the present invention is to realize a brake control method for a continuously variable transmission that is practically advantageous and can improve safety.

[Means for solving problems]

In order to achieve this object, the present invention reduces and increases the groove width between both pulley parts of a fixed pulley part and a movable pulley part attached to the fixed pulley part so as to be able to move toward and away from the fixed pulley part. In a clutch control method for a continuously variable transmission that performs speed change control to change the gear ratio by decreasing or increasing the rotation radius of a belt wrapped around the belt, a control unit that inputs various detection signals of vehicle driving conditions is provided, and the braking force is used to control the speed of the vehicle. A brake means for decelerating or stopping the vehicle is provided, and the control section is manually supplied with various detection signals of vehicle driving conditions, and the control section operates the brake means only when a detection signal of a specific shift lever position is input. It is characterized in that it is controlled to make it happen.

[Effect]

According to the above-mentioned invention, when a detection signal of a specific shift lever position is input to the control section, the control section controls the operation of the braking means, prevents unnecessary braking force from being held, and applies the braking force only when necessary. It effectively maintains braking force, prolongs the service life of the brake means, and improves vehicle safety.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

1 to 6 show embodiments of this invention. Fourth
．． In Figure 5, 2 is a belt-driven continuously variable transmission;
A is a belt, 4 is a driving side pulley, 6 is a driving side fixed pulley part, 8 is a driving side movable pulley part, 10 is a driven side pulley, 12 is a driven side fixed pulley part, 14 is a driven side It is a movable pulley piece. The drive side pulley 4 is a 4.5th pulley.
As shown in the figure, a driving side fixed pulley piece 6 is fixed to the rotating shaft 16, and a driving side movable pulley piece 8 is attached to the rotating shaft 16 so as to be movable in the axial direction of the rotating shaft 16 but not rotatable. and has. Further, similarly to the driving pulley 4, the driven side pulley 10 also has a driven side fixed pulley part 1.
2 and a driven side movable pulley piece 14.

The driving side movable pulley piece 8 and the driven side movable pulley piece 14 have a first. Second housings 18.20 are respectively mounted and define first and second hydraulic chambers 22.24, respectively. At this time, a biasing means 26 made of a spring or the like is provided in the second hydraulic chamber 24 on the driven side to bias the second housing 20 in the direction of expansion of the second hydraulic chamber 24.

An oil pump 28 is provided on the rotating shaft 16, and the oil pump 28 is connected to the first and second hydraulic chambers 22,24.
The first oil passages 30 and 30 communicate with each other through second oil passages 30 and 32, and a primary pressure control valve 34, which is a speed change control valve, that controls the primary pressure, which is the input shaft sheave pressure, is interposed in the middle of the first oil passage 30. In addition, a line pressure (generally 5 to 25 kg/c
r1) to a constant pressure (1.5 to 2.0 kg/c+d), and a first three-way solenoid valve 42 for primary pressure control is connected to the primary pressure control valve 34 through a fourth oil passage 40. Communicate.

Further, a line pressure control valve 4 having a relief valve function for controlling the line pressure, which is the pump pressure, is disposed in the middle of the second oil passage 32.
4 is communicated through a fifth oil passage 46, and a second three-way solenoid valve 50 for line pressure control is communicated with this line pressure control valve 44 through a sixth oil passage 48.

Furthermore, a clutch pressure control valve 52 for controlling the clutch pressure is installed in the seventh oil passage 5 in the middle of the second oil passage 32 on the second hydraulic chamber 24 side than the part communicating with the line pressure control valve 44.
4, and a third three-way solenoid valve 58 for clutch pressure control is connected to this clutch pressure control valve 52 through an eighth oil passage 56.
Communicate.

Further, the primary pressure control valve 34, the first solenoid valve 42 for primary pressure control, the constant pressure control valve 38, the sixth oil passage 48, the second solenoid valve 50 for line pressure control, and the clutch pressure control valve 52 are connected to a ninth oil The passages 60 communicate with each other.

The clutch pressure control valve 52 is connected to the hydraulic clutch 62 by a tenth
This tenth
A pressure sensor 68 is communicated with an eleventh oil passage 66 midway through the oil passage 64 .

This pressure sensor 68 can directly detect the oil pressure when controlling the clutch pressure in hold and start modes, etc., and contributes to instructing the detected oil pressure to be the target clutch pressure. Furthermore, since the clutch pressure is equal to the line pressure in the drive mode, it also contributes to line pressure control.

An input shaft rotation detection gear 70 is provided on the outside of the first housing 18.
A first rotation detector 72 on the input shaft side is provided near the outer peripheral portion of the input shaft rotation detection gear 70. Further, an output shaft rotation detection gear 74 is provided on the outside of the second housing 20, and a second rotation detector 76 on the output shaft side is provided near the outer peripheral portion of the output shaft rotation detection gear 74. Detection signals from the first rotation detector 72 and the second rotation detector 76 are output to a control section 82, which will be described later, to determine the engine rotation speed and belt ratio.

The hydraulic clutch 62 is provided with an output transmission gear 78,
A third rotation detector 80 for detecting the rotation of the final output shaft is provided near the outer periphery of the gear 78.

In other words, the third rotation detector 80 detects the rotation of the reduction gear, the differential, the drive shaft, and the final output shaft directly connected to the tires, and is capable of detecting the vehicle speed. Further, the second rotation detector 76 and the third rotation detector 80 can also detect the rotation of the hydraulic clutch 62 before and after, contributing to the detection of the amount of clutch slip.

Furthermore, various conditions such as a throttle opening of a carburetor (not shown) of the vehicle, engine rotation from the first to third rotation detectors 72, 76, 80, vehicle speed, etc. are input, and the duty ratio is changed to perform gear change control. The controller 82 controls the first three-way solenoid valve 42 and constant pressure control valve 38 for primary pressure control, the second three-way solenoid valve 50 for line pressure control, and the third three-way solenoid valve 58 for clutch pressure control. It is configured to control the opening/closing operation and also control the pressure sensor 68. Further, in detail, the functions of the various signals and human input signals input to the control section 82 are as follows: (1) Shift lever position detection signal...P, R, , N, D, , L Line pressure and ratio required for each range, clutch control (2), carburetor throttle opening detection signal, etc.
・Detection of engine torque from memory input into the program in advance, determination of target ratio or target engine speed (3), detection signal of carburetor idle position...
・Improved precision in correction and control of the capreta throttle opening sensor (4), accelerator pedal signal...Detects the driver's intention based on the accelerator pedal depression state, and controls when driving or when oil is being pumped. Determine the direction (5), Brake signal...Detects whether or not the brake pedal is depressed, determines the control direction such as clutch release (6), Power mode option signal... It can be used as an option to make the performance sporty (or economical).

Note that 84 is a piston of the hydraulic clutch 62, 86 is an annular spring, 88 is a first pressure coupler, 90 is a friction plate, 92 is a second pressure coupler, 94 is an oil pan, and 96 is an oil filter.

The control section 82 is configured to input various detection signals, which will be described later, regarding vehicle operating conditions, and to control the brake means 98, which will be described later, to operate only when a detection signal of a specific shift lever position is input.

More specifically, the control section 82 controls the shift lever when the shift lever position is L.
A detection signal when the position is reached is input, and the brake means 98 is controlled to operate in order to maintain the braking force.

In other words, the driving modes of the belt-driven continuously variable transmission 2 include: (1) Economy mode - General driving on a flat road while maintaining low fuel consumption (2)
), Power mode: Sporty driving or rough road driving (3), Low mode: Three typical patterns for driving that require high torque transmission or use of engine braking. Yes, and the driving mode often used on slopes is low mode. For this reason, the brake means 98 is controlled to be operated by the brake hold program only when the shift lever position at which the shift position is "low" is at the L position.

In addition, as shown in FIG. L)
, power mode option switch, engine speed, clutch input shaft speed, and clutch output shaft speed (vehicle speed).

Furthermore, as shown in FIG. 2, the control section 82 includes a second three-way solenoid valve 50 for line pressure control, a third three-way solenoid valve 58 for clutch pressure control, a first three-way solenoid valve 42 for primary pressure control, and a controller. An operation indicator lamp 1 that displays the operating status of the power retention solenoid valve 100 and the braking force retention solenoid valve 100
02 is connected.

Next, the determination conditions for each clutch control mode will be explained.

(1) Neutral mode: Determined when the shift lever position is in the N or P position, and at this time the clutch pressure is set to Okg/crA.

(2) Hold mode...The shift lever is in the R, D, or L position, the engine speed is less than 1100 Orp, the clutch output shaft (vehicle speed) is less than 8 km/H, and It is determined when the accelerator pedal signal is off when the accelerator pedal is not depressed, and at this time the clutch pressure is controlled by feedback control so that the target clutch pressure is 3 or 5.
The duty output signal is controlled to achieve kg/cni (clutch engagement pressure).

(3) Normal start mode...The shift lever is in the R, D, or L position, the clutch output shaft (vehicle speed) is less than 8 km/h, the accelerator pedal signal is on, and This determination is made when the engine speed is 1100 Orp or more. In addition, as shown in Figure 3, this start mode control is based on the engine map (which is determined by the throttle opening in the engine output characteristics stored in advance) by converting the engine torque obtained by the throttle opening when the accelerator pedal is depressed. This engine torque value is multiplied by a proportional gain to convert it into a clutch pressure value that allows the clutch to transmit the calculated engine torque (referred to as feedforward amount). Furthermore, a target engine speed is calculated from the same throttle opening according to the start mode schedule, and the actual engine speed is feedback-controlled to convert the difference from the target value into a clutch pressure value. The start mode schedule is a map in which the engine speed determined by the throttle opening in the engine output characteristics is stored in advance. In the above calculation loop, a calculation value is calculated to increase the clutch pressure in order to lower the actual engine speed when the actual engine speed is higher than the target engine speed (speed loop deviation).

Then, the start mode target clutch pressure is determined from the feedforward amount and the speed loop deviation. The actual clutch pressure is controlled by the duty output signal so as to reach the target clutch pressure through feedback control.

(4) Special start mode...When the shift lever is in either the R or DSL position, the clutch output shaft (vehicle speed') is 9 km/H.
It is determined in the above case, and the control of this special start mode calculates the clutch pressure conversion value so that the difference between the clutch input shaft rotation speed and the clutch output shaft rotation speed (clutch slip amount) becomes the correction amount φ, Similar to the start mode described above, the actual clutch pressure is controlled by the duty output signal by feedback control so as to reach the target clutch pressure.

(5) Drive mode...The shift lever is in R, D, or L position, and the clutch output shaft (vehicle speed) is 81ua/H or higher,
Further, it is determined when the clutch slip amount is 2 Orpm or less, and the clutch pressure becomes maximum in order to lock up the clutch.

The brake means 98 will be explained in detail. The brake means 98 is, for example, an actuator 10, as shown in FIG.
4, a constant pressure chamber 110 and a variable pressure chamber 112 are defined within the actuator 104 by a diaphragm 106 and a piston 108, and the diaphragm 106 has a movable rod 114 connected to a brake pedal (not shown).
Connect one end of.

A negative pressure passage 116 is connected to the constant pressure chamber 110 in an intake pipe (not shown).
At the same time, a check valve 118 is provided in the middle of this negative pressure passage 116 to prevent air from flowing out from the constant pressure chamber 110 side to the intake pipe side.

Further, an atmospheric passage 120 is formed in the cylindrical portion 108a of the piston 108 by the rod 114, and a first opening/closing valve 122 is provided in the middle of the atmospheric passage 120 to open and close the atmospheric passage 120 according to the operation of the rod 114. . Further, a communication passage 124 is formed in the piston 108 to communicate the constant pressure chamber 110 and the variable pressure chamber 112, and the rod 11 is connected to the end of the communication passage 124 on the variable pressure chamber 112 side.
The second on-off valve 1 opens and closes the communication passage 124 according to the operation of the second on-off valve 1.
26 is provided.

Furthermore, for example, at the constant pressure chamber 110 side end of the communication passage 124 that communicates the constant pressure chamber 110 and variable pressure chamber 112 for operating the brake means 98, there is provided an electromagnetic force retaining electromagnetic valve that is controlled to open and close by the control section 82. A valve 100 is provided.

Next, the effect will be explained.

In the belt-driven continuously variable transmission 2, as shown in Fig. 3.4, an oil pump 28 located on the rotating shaft 16 operates in response to the drive of the rotating shaft 16, and the oil is pumped throughout the bottom of the transmission. It is absorbed from the oil pan 94 through the oil filter 96. The line pressure, which is this pump pressure, is controlled by a line pressure control valve 44, and if the amount of leakage from this line pressure control valve 44, that is, the amount of relief from the line pressure control valve 44 is large, the line pressure will be low; If it is less, the line pressure will be higher.

Further, the line pressure control valve 44 has a shift control characteristic that performs three-stage control by varying the line pressure in a full low state, a full over top state, and a fixed ratio state.

The operation of the line pressure control valve 44 is controlled by a dedicated second three-way solenoid valve 50, and the line pressure control valve 44 operates in accordance with the operation of the second three-way solenoid valve 50. , the second three-way solenoid valve 50 is controlled at a duty rate of a constant frequency. That is, the duty rate θ% is a state in which the second three-way solenoid valve 50 does not operate at all, the output side is connected to the atmosphere side, and the output oil pressure is zero. Further, when the duty rate is 100%, the second three-way solenoid valve 50 operates and the output side is connected to the atmosphere side, and the maximum output oil pressure is the same as the control pressure, and the output oil pressure is varied depending on the duty rate. Therefore, the characteristics of the second three-way solenoid valve 50 are approximately linear, and the line pressure control valve 44 can be operated in an analog manner, and the duty rate of the second three-way solenoid valve 50 can be changed arbitrarily. Line pressure can be controlled.

Further, the operation of the second three-way solenoid valve 50 is controlled by the control section 82.
controlled by.

The primary pressure for speed change control is provided by the primary pressure control valve 3.
Similarly to the line pressure control valve 44, the operation of the primary pressure control valve 34 is also controlled by a dedicated first three-way solenoid valve 42. This first three-way solenoid valve 42 is used to conduct the primary pressure to the line pressure or to conduct the primary pressure to the atmosphere side,
The belt ratio is caused to shift to the full overdrive side by conducting to the line pressure, or to the full low side by conducting to the atmosphere side.

The clutch pressure control valve 52 that controls the clutch pressure is connected to the line pressure when the maximum clutch pressure is required, and connected to the atmosphere side when the minimum clutch pressure is required. As with the line pressure control valve 44 and the primary pressure control valve 34, the operation of this clutch pressure control valve 52 is also controlled by a dedicated third three-way solenoid valve 58, and the explanation thereof will be omitted.

Clutch pressure varies within a range from minimum atmospheric pressure (zero) to maximum line pressure.

There are four basic patterns for clutch pressure control, which will be described later.These basic patterns are: (1) Neutral mode: When the shift position is N or P and the clutch is completely disengaged, the clutch pressure is the lowest. Pressure (zero) (2),
Hold mode: When the shift position is D or R and you release the throttle and have no intention of driving, or when you want to decelerate and cut off the engine torque while driving, the clutch pressure is set to a low level that the clutch contacts ( 3) Start mode: When starting or when trying to re-engage the clutch after the clutch has been disengaged, the clutch pressure is adjusted to prevent the engine from revving up and to maintain engine-generated torque (clutch input) that allows the vehicle to operate smoothly. (4) appropriate level according to the engine torque (4), drive mode... When the clutch is fully engaged in a complete driving state, the clutch pressure is high enough to withstand the engine torque. There are four levels. In this basic pattern, (11) is performed by a dedicated switching valve (not shown) that is linked to the shift operation, and the other (2), (3), and (4) are performed by the control section 82.
This is done by controlling the duty rate of the third three-way solenoid valve 42, 50, 58. Particularly in the state (4), the clutch pressure control valve 52 controls the seventh oil passage 54 and the first oil passage.
0 oil passage 64 to create a state of maximum pressure generation,
Clutch pressure will be the same as line pressure.

In addition, the primary pressure control valve 34 and the line pressure control valve 4
4, and the clutch pressure control valve 52 is controlled by the output oil pressure from the first to third three-way solenoid valves 42.50, respectively.
．． The control oil pressure that controls the pressure control valve 58 is a constant oil pressure produced by the constant pressure control valve 38. This control oil pressure is always lower than the line pressure, but it is a stable and constant pressure. In addition, the control oil pressure is controlled by each control valve 34, 44.
52 is also introduced to stabilize these control valves 34, 44, 520.

Electronic control of the belt-driven continuously variable transmission 2 will be explained.

Continuously variable transmission 2 is hydraulically controlled, and in response to commands from control unit 82, appropriate line pressure for belt retention and torque transmission, primary pressure for changing gear ratio, and clutch engagement are ensured. Clutch pressure is secured for each.

Next, a description will be given along with a brake control flowchart of the belt-driven continuously variable transmission 2 shown in FIG.

First, the brake control program starts (200)
Then, it is determined whether the shift position is "low", that is, whether the shift lever position is the L position (202).
If YES, a general brake hold program is executed (204), and if NO, a main program is executed (206). After the brake hold program is executed (204), the main program is executed (206).

Next, a description will be given along with a general brake hold flowchart of the belt-driven continuously variable transmission 2 shown in FIG.

First, the brake hold program starts (300
) Then, the time from the last vehicle speed rotation signal input (ST
PCNT) is 1.5 seconds or more, that is, the vehicle speed O is 1.
．． It is determined whether the state of vehicle speed O continues for 5 seconds (302), and if the state of vehicle speed O is not continuous for 1.5 seconds, it is determined whether or not the mode is normal start mode (304), and the state of vehicle speed O is determined. If this continues for 1.5 seconds, the process moves to judgment (306) as to whether or not the brake switch is in the on state.

Then, if the judgment (306) is No, the process moves to the above-mentioned judgment (304) as to whether or not it is the normal start mode,
If YES, it is determined whether the accelerator pedal switch is in the off state (308).

If this judgment (308) is No, the process moves to the above-mentioned judgment (304) as to whether or not it is the normal start mode.
In the case of S, a closing signal of the braking force retention solenoid valve 100 and an operation indicator lamp 1020 on signal are output, and the control unit 82 controls the braking force retention solenoid valve 100 to close and maintain the braking force. (310).

In addition, the above-mentioned determination of whether or not the normal start mode is selected (3)
If 04) is YES, it is determined whether the clutch pressure (PCLU) is 5 kg/c4 or more (312), and if NO, it is determined whether the special start mode is in effect (314).

In the above judgment (312), the clutch pressure (PCLU)
is 5 kg/cn1 or more, an open signal for the braking force holding solenoid valve 100 and an off signal for the operation indicator lamp 102 are output, and the control unit 82 opens the braking force holding solenoid valve 100 to reduce the braking force. 31 in a controlled manner to erase
6), clutch pressure (PCL U) is 5 kg/
If it is less than c, the brake control program is ended (320).

In addition, the above-mentioned judgment of whether or not the special start mode is in effect (
314) is YES, the braking force holding solenoid valve 1
00 open signal and an off signal for the operation indicator lamp 102, and the control unit 82 controls the braking force holding solenoid valve 100 to open and erase the braking force (316).
, in the case of No, the brake control program is ended (320).

As a result, the control section 82 can control the braking means 98 to operate only when a detection signal indicating that the shift lever is in the "low" position, that is, the shift lever is in the L position, is input. , it is possible to effectively maintain braking force only when necessary, such as when stopping or starting on an uphill slope, and it is also possible to prevent unnecessary braking force from being maintained at shift lever positions other than the L position, thereby extending the service life of the brake means. It can be made longer, which is economically advantageous, and can prevent the vehicle from moving backwards, improving safety.

In addition, by being able to effectively maintain braking force only when necessary, such as when stopping or starting on an uphill slope, it is possible to prevent reverse movement when starting on an uphill slope, and it is possible to easily perform starting operations on an uphill slope, making it practical. It is advantageous.

Furthermore, by controlling the brake means 98 to operate by the control unit 82, it can be realized only by software support without the need for adding or modifying hardware.
It can be easily added to a conventional program with only a small increase in memory capacity, the structure does not become complicated, and it can contribute to cost reduction.

Note that the present invention is not limited to the above-described embodiments, and various modifications can be made.

For example, in the embodiment of the present invention, the control unit operates the brake means to maintain the braking force only when a detection signal indicating a specific shift lever position, that is, the shift lever position is the L position, is input. However, it is also possible to control the braking means to operate by means of a switch that operates when the shift lever position reaches a desired shift lever position other than the L position or a specific shift lever position.

〔Effect of the invention〕

As described above in detail, according to the present invention, a control section is provided to input various detection signals of vehicle driving conditions, and
A brake means is provided to decelerate or stop the vehicle using braking force, and the control unit manually sends various detection signals of the vehicle operating status.
Since the control section controls the operation of the brake means only when a detection signal for a specific shift lever position is input, the control section controls the operation of the brake means only when a detection signal for a specific shift lever position is input. It is possible to control the operation of the brake means, effectively hold the braking force only when necessary such as stopping or starting on an uphill slope, and prevent unnecessary holding of the braking force, thereby extending the usable life of the brake means. This is economically advantageous and can prevent the vehicle from moving backwards, improving safety. In addition, by being able to effectively maintain braking force only when necessary, such as when stopping or starting on an uphill slope, it is possible to prevent reverse movement when starting on an uphill slope, and it is possible to easily perform starting operations on an uphill slope, making it practical. It is advantageous. Furthermore, it can be realized only by software support, and can be easily added to existing programs by increasing the amount of memory by a small amount, without complicating the structure and reducing costs. This can contribute to

[Brief explanation of the drawing]

1 to 6 show embodiments of the present invention, FIG. 1 is a flowchart for brake control based on lever shift position in a continuously variable transmission, FIG. 2 is a flowchart for general brake control in a continuously variable transmission, and FIG. Figure 3 is a plot diagram of the control section of the continuously variable transmission, Figure 4 is a schematic diagram of the belt-driven continuously variable transmission, Figure 5 is a block diagram of the belt-driven continuously variable transmission, and Figure 6 is the control section. It is a schematic diagram of a power retention mechanism. In the figure, 2 is a belt-driven continuously variable transmission, 2A is a belt, 4 is a driving pulley, 10 is a driven pulley, 3
2 is the second oil passage, 34゛ is the primary pressure control valve, 3
8 is a constant pressure control valve, 42 is a first three-way solenoid valve, 44 is a line pressure control valve, 50 is a second three-way solenoid valve, 52 is a clutch pressure control valve, 58 is a third three-way solenoid valve, 62 is a hydraulic clutch, 6
8 is a pressure sensor, 72 is a first rotation detector, 76 is a second rotation detector, 80 is a third rotation detector, 82 is a control unit, 94
1 is an oil pan, 96 is an oil filter, 98 is a brake means, 100 is a solenoid valve for retaining braking force, 102 is an operation indicator lamp, 104 is an actuator, 106 is a diaphragm, 108 is a piston, 110 is a constant pressure chamber, 112 is a variable pressure chamber , 124 are communication paths. Fig. 3 Fig. 6 i Signature ship procedure host city device (self-motivated) September 16, 1988 1, Indication of the incident Patent Application No. 1983-310950 2, Name of the invention Brake control method for continuously variable transmission 3, Relationship with the case of the person making the amendment Patent applicant address 300 Takatsuka, Kamimura, Hamana-gun, Shizuoka Prefecture Name (
208) i Gohon Jidosha Kogyo Co., Ltd. 4, Agent 101 Ta 03-292-
4411 (Representative) Address Saigo Patent Building, 2-8 Kanda Ogawamachi, Chiyoda-ku, Tokyo Name (8005) Patent Attorney Nishi Suzudo Yoshimi 7, Contents of Amendment 3, (1), Page 3, Line 20 of the Specification “In position P,
" is corrected to "is in the R position." (2), [Constant pressure (1,5~2゜0kg10111)J] on page 9, line 3 of the specification
++I) Correct to J. (3) On page 22, line 16 of the specification, "by D or R" is corrected to "by rD, L or R." -(4) In the second line of page 21 of the specification, "output side is on the atmospheric side" is corrected to "output side is on the input side". (5) "Sui" on page 29, line 7 of the specification is corrected to "suifuchi". (4), Figure 3 of the drawing is corrected as shown in the attached drawing.

Claims (1)

[Claims] 1. A fixed pulley piece and a movable pulley piece that is attached to the fixed pulley piece so as to be able to come into contact with and separate from the fixed pulley piece, and the width of the groove between the two pulley pieces is decreased or increased, and the groove is wound around both pulleys. In a clutch control method for a continuously variable transmission that performs speed change control to change the gear ratio by decreasing or increasing the rotation radius of a belt that is rotated, a control unit that inputs various detection signals of vehicle driving conditions is provided, and the braking force is used to decelerate the vehicle or A brake means for stopping the vehicle is provided, various detection signals of the vehicle driving state are inputted to the control section, and the control section is controlled so that the brake means is operated only when a detection signal of a specific shift lever position is inputted. A brake control method for a continuously variable transmission characterized by: 2. The control unit is a control unit that receives a detection signal when the shift lever position is at the L position and controls the operation of the brake means to maintain the braking force. Brake control method for the continuously variable transmission described.