JPH01153367A - Method of controlling brake in continuously variable transmission - Google Patents

Abstract

PURPOSE:To effectively hold braking force by providing a solenoid valve on the way of a communication passage for actuating a brake means, and by delivering various kinds of detection signals indicating a vehicle driving condition to a control section so that the control section controls the opening and closing of the solenoid valve to control the operation of the brake means. CONSTITUTION:A braking force holding solenoid valve 100 is provided on the way of a communication passage for actuating a brake means, and a control section 82 receives various kinds of detection signals indicating a vehicle drive condition. The control section 82 controls the opening and closing of the solenoid valve 100 so as to control the operation of the brake means. With this arrangement, when the control section 82 receives the various kinds of detection signals indicating a vehicle drive condition, the control section controls the opening and closing of the solenoid valve 100 in order to control the brake means so as to effectively hold a brake force, 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,
The present invention relates to a brake control method for a continuously variable transmission that controls the opening and closing of a solenoid valve to control the operation of a brake means as desired, effectively maintaining braking force, and improving vehicle safety.

[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 electromagnetic 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, the hydraulic clutch is completely off, and the clutch pressure is O.

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/ci, causing the hydraulic clutch to slip to reduce a small amount of creep. It is occurring. In this hold mode, when the shift lever is in the D or L position, when restarting after stopping, it is necessary to switch from the brake pedal to the accelerator pedal. The control mode is switched from to start mode.

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.

[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 to provide a brake means for decelerating or stopping the vehicle using braking force. A solenoid valve is provided in the communication path to be operated, and a control unit to which various detection signals of vehicle operating conditions are input controls the opening and closing of the solenoid valve to control the operation of the brake means, thereby operating the brake means as desired. The object of the present invention is to realize a practically advantageous brake control method for a continuously variable transmission, which can control the braking force, effectively maintain the braking force, and improve the safety of the vehicle.

[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 solenoid valve is provided in the communication path for operating the brake means, and various detection signals of vehicle operating conditions are input to the control section, and the control section opens and closes the solenoid valve. and controlling the operation of the braking means.

[Effect]

According to the above-described invention, when the control section receives various detection signals of the vehicle driving state, the control section controls the opening and closing of the solenoid valve, controls the operation of the brake means, and effectively maintains the braking force; Improves vehicle safety.

〔Example〕

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

1 to 5 show embodiments of this invention. Second
．． In Figure 4, 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 3.4th 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.

First and second housings 18.20 are attached to the drive side movable pulley piece 8 and the driven side movable pulley piece 14, respectively, and first and second hydraulic chambers 22.24 are formed, 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 a primary pressure, which is a manual 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
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.

Also, 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. The clutch pressure control valves 52 are communicated with each other through a ninth oil passage 60. 'The clutch pressure control valve 52 is communicated with the hydraulic clutch 62 through a tenth oil passage 64, and a pressure sensor 68 is communicated with the tenth oil passage 64 through an eleventh oil passage 66.

This pressure sensor 68 can directly detect the oil pressure when controlling the clutch pressure in hold and start modes, etc., and contributes to the command to set the detected oil pressure as the target clutch pressure. Furthermore, since the clutch pressure becomes 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, which contributes to detecting the amount of cranotis lithopsis.

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. In addition, the various signals input to the control section 82 and the functions of the input signals are as follows: (1) Shift lever position detection signal: P, R, N, , D, L, etc. Line pressure and ratio required for each range by range signal, clutch control, carburetor throttle opening detection signal...
Detects the engine torque from the memory input into the program in advance, determines the target ratio or target engine speed, detects the carburetor idle position, improves accuracy in correction and control of the carburetor throttle opening sensor. ■, Accelerator pedal signal: Detects the driver's intention based on the state of depression of the accelerator pedal, and determines the control direction when driving or starting ■, Brake signal: Brake pedal depression operation Detects the presence or absence of the vehicle and determines the direction of control such as clutch disengagement■, Power mode option signal...It is used as an option to make the performance of the vehicle more sporty (or more 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 of the vehicle operating state, which will be described later, to control the opening and closing of a braking force holding solenoid valve 100, which will be described later, and to control the operation of a brake means 98, which will be described later. Specifically, the control unit 82 closes the electromagnetic valve 100 when the vehicle speed continues to be 0 for 1.5 seconds, a brake switch (not shown) is turned on, and an accelerator pedal switch (not shown) is turned off. The solenoid valve 10 is controlled to
0 is controlled to open.

The control unit 82 also includes clutch pressure, cube throttle opening, idle switch, accelerator pedal switch, brake switch, shift lever position P, RSN.
, D, L, power mode option switch, engine speed, clutch input shaft speed, and clutch output shaft speed (vehicle speed).

Furthermore, as shown in FIG. 1, 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 the first three-way solenoid valve 42 for primary pressure control. A braking force retention solenoid valve 100 and an operation display lamp 102 that displays the operating state of the braking force retention solenoid valve 1oo are connected.

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

(2) 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/cnl.

■Hold mode...The shift lever is in either the RSD or L position, the engine speed is less than 1100 Orp, the clutch output shaft (vehicle speed) is less than 3km/H, and the accelerator pedal is depressed. The target clutch pressure is determined to be 3.5 kg by feedback control.
/cnf (clutch engagement pressure) by controlling the duty output signal.

■Normal start mode...The shift lever is in either the R or DSL position, the clutch output shaft (vehicle speed) is less than 3 km/h, the accelerator pedal signal is on, and the engine speed is It is determined when the value 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 by feed bank control so that it becomes the target clutch pressure.

■Special start mode: This is determined when the shift lever is in the R, D, or L position and the clutch output shaft (vehicle speed) is 8 km/h or higher, and the control of this special start mode is ,
Difference between clutch input shaft rotation speed and clutch output shaft rotation speed (
The clutch pressure conversion value is calculated so that the clutch slip amount) becomes the correction amount Φ, and as in the start mode described above,
The actual clutch pressure is controlled by the duty output signal so as to reach the target clutch pressure through feedback control.

■ Drive mode: Determined when the shift lever is in the R, D, or L position, the clutch output shaft (vehicle speed) is 8 km/h or more, and the clutch slip amount is 2 Orpm or less, Clutch pressure is maximized to lock up the clutch.

When in the hold mode, a hold control mode within the control section 82 is selected. This hold control mode prepares a hold mode schedule determined by the engine speed for each shift lever position. In other words, hold mode schedule 1 when the shift lever position is D and R, and hold mode schedule 1 when the shift lever position is L.
In addition to the two types of hold mode schedule 2, it is also possible to set a number of hold mode schedules equal to the number of shift lever positions.

The brake means 98 will be explained in detail. The brake means 98 has an actuator 104, as shown in FIG.
and the piston 108 create a constant pressure chamber 110 and a variable pressure chamber 11.
2, and one end of a movable rod 114 connected to a brake pedal (not shown) is connected to the diaphragm 106.

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 loft 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.

A communication path for operating the brake means 98, for example, a communication path 124 that communicates the constant pressure chamber 110 and the variable pressure chamber 112.
The braking force holding solenoid valve 100, which is controlled to open and close by the control section 82, is provided at the end of the constant pressure chamber 110 side.

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 into the oil at the bottom of the transmission. It is absorbed from the 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, when the duty rate is 0%, the second three-way solenoid valve 50 does not operate at all, the output side is connected to the atmosphere, and the output oil pressure becomes 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 side 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. (1) of this basic pattern 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, and 52.

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, the time since the last vehicle speed rotation signal input (STP
CNT) is 1.5 seconds or more, that is, the vehicle speed O is 1.
It is determined whether the period continues for 5 seconds (202), and the vehicle speed is set to 0.
If this state does not continue for 1.5 seconds, the judgment (204) is made as to whether or not the mode is normal start mode, and the vehicle speed is
If this state continues for 1.5 seconds, the process moves to a determination (206) as to whether or not the brake switch is in the on-operation state.

If the determination (206) is NO, the process moves to the above-described determination (204) 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 (208).

If this judgment (208) is No, the process moves to the above-mentioned judgment (204) as to whether or not it is the normal start mode.
In the case of S, a closing signal for the braking force retention solenoid valve 100 and an ON signal for the operation indicator lamp 102 are output, and the control unit 82 closes the braking force retention solenoid valve 100 to maintain the braking force. control (210);

In addition, the above-mentioned determination of whether or not the normal start mode is selected (2)
04) is YES, the clutch pressure (P CLU
) is 5 kg/c or more (212), and if No, it is determined whether the special start mode is in effect (214).

In the above judgment (212), the clutch pressure (PCLU)
is 5 kg/ca1 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 control the braking force holding solenoid valve 100. In order to eliminate the power, the clutch pressure (P CL LJ) is 5 k.
If it is less than g/crA, the brake control program is ended (220).

In addition, the above-mentioned special start mode is determined (
214) is YES, the braking force retention solenoid valve 1
00 open signal and an off signal for the operation indicator lamp 102, the control unit 82 controls the braking force holding solenoid valve 100 to open and erase the braking force (216).
, in the case of No, the brake control program is ended (220).

As a result, when stopping due to braking, the control section 8
2 closes the braking force retaining electromagnetic valve 100, and the braking force can be retained by the brake means 9, thereby improving the safety of the vehicle, especially when stopped on an uphill slope.

Also, in normal start mode and when the clutch pressure is 5.
The braking force is maintained until the clutch pressure is controlled by kg/cd or more, special start mode, or various drive mode conditions, and when the various conditions are satisfied, the solenoid valve 100 is opened to eliminate the braking force. By controlling the vehicle to the extent possible, it is possible to reliably prevent the vehicle from going backwards due to the braking force when starting on an uphill slope, and it is possible to perform a safe starting operation and improve safety.

Furthermore, if the clutch pressure is 5 in normal start mode and
kg/ct or more, or until various conditions of special start mode or drive mode are satisfied, the solenoid valve 100 is closed and the braking force is controlled to be maintained, so that, for example, when starting on an uphill slope, the handbrake can be operated. is no longer necessary, and usability can be improved.

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 braking force holding solenoid valve 100, which is controlled to open and close by the control section 82, is provided at the end of the brake means 98 on the constant pressure chamber 110 side,
The opening and closing of this solenoid valve 100 for retaining braking force was controlled by the control section 82, but the solenoid valve 100 for retaining braking force was provided in the brake hydraulic piping or other parts, and the solenoid valve 100 for retaining braking force was controlled by the control section 82. It is also possible to control the braking force by opening and closing the brake lever 82 to maintain the braking force.

〔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 a solenoid valve is provided in the communication path for operating the brake means, and the opening and closing of the solenoid valve is controlled by a control section to which various detection signals of the vehicle operating state are input. Since the operation of the brake means is controlled, when the vehicle is brought to a stop by braking, the control section closes the braking force retaining electromagnetic valve to retain the braking force in the brake means, thereby improving the safety of the vehicle. In addition, by controlling the operation of the braking means to maintain the braking force until the clutch pressure is controlled, and canceling the braking force by opening the solenoid valve as desired, the clutch pressure can be controlled especially when starting on an uphill slope. The braking force that is maintained until the pressure is controlled can reliably prevent the vehicle from moving backwards, allowing safe starting operations and improving safety.

Furthermore, by controlling the operation of the brake means to maintain the braking force by closing the electromagnetic valve as desired, it is no longer necessary to operate the handbrake when starting on an uphill slope, thereby improving usability.

[Brief explanation of the drawing]

1 to 5 show embodiments of the present invention, FIG. 1 is a flowchart for brake control of a continuously variable transmission, FIG. 2 is a block diagram of a control section of a continuously variable transmission, and FIG. 3 is a belt-driven type FIG. 4 is a schematic diagram of the continuously variable transmission, FIG. 4 is a block diagram of the belt-driven continuously variable transmission, and FIG. 5 is a schematic diagram of the braking force holding 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 a second oil passage, 34 is a primary pressure control valve, 38
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, 68
1 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 is an oil pan, 96 is an oil filter, 98 is a brake means, 100 is a 102 is an operation display 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, and 124 is a communication passage. Patent Applicant Meiki Jidosha Kogyo Co., Ltd. Agent Patent Attorney Yoshimi Saigo Figure 1 Figure 2 Figure 5 ↑ R: *S Procedure ordering device (spontaneous) 1. Display of the case Japanese Patent Application No. 62-310949 2, Name of the invention Brake control method for a continuously variable transmission 3, Person making the amendment Relationship to the case Patent applicant Address 300 Takatsuka, Kamimura, Hamana-gun, Shizuoka Prefecture Name ( 2
0B) Suzuki Motor Co., Ltd. 4, Agent 101 Ta 03-292-
4411 (Representative) Address: 2-8-7, Kanda Ogawamachi, Chiyoda-ku, Tokyo Contents of amendment (1): "Located at P position" on page 4, line 4 of the specification was changed to "
It is in the R position.'' (2), "Constant pressure (1,5~2°0ksr/cd) J" on page 8, line 9 of the specification is replaced with "Constant pressure (4~5kg/cJ) J
Correct to. (3), "by D or R" in the first line of page 22 of the specification is r
Correct it to "D,, L or R". (4), Figure 1 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 is provided, an electromagnetic valve is provided in the communication path for operating the brake means, various detection signals of the vehicle operating state are inputted to the control section, and the control section controls opening and closing of the electromagnetic valve, A brake control method for a continuously variable transmission, comprising controlling the operation of the brake means. 2. The control unit maintains a state where the vehicle speed is 0 for 1.5 seconds,
In addition, when the brake switch is on and the accelerator pedal switch is off, the solenoid valve is controlled to close, and when the clutch pressure is 5 kg/cm^2 or more in normal start mode, or special start mode, or drive mode. 2. The brake control method for a continuously variable transmission according to claim 1, wherein the control section controls the solenoid valve to open when in the mode.