JPH054539B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a shift control device for a continuously variable transmission that performs open-loop control of a continuously variable transmission mechanism using a control means based on shift control information.

[Conventional technology]

A conventional speed change control device for a continuously variable transmission is disclosed in, for example, Japanese Patent Laid-Open No. 58-54262.

This device moves the roller support by operating the main control valve according to the depression position of the accelerator pedal and the negative pressure from the manifold, and mechanically feeds back the movement position to the main control valve using a precess cam. It is configured to obtain a desired gear ratio by tilting the power roller to a desired position.

[Problem that the invention seeks to solve]

However, in the case of the above-mentioned gear change control device for the continuously variable transmission, the gear ratio is controlled by mechanically transmitting the amount of depression of the accelerator pedal and the negative pressure from the manifold to the main control valve. However, there were problems in that the control mechanism became larger and its structure became more complicated.

In order to solve this problem, it is conceivable to use a stepping motor as the main control valve and control it electrically using open loop control, but in this case, a control origin is set and the It is necessary to control the amount of movement of the

By the way, when a stepping motor is subjected to open loop control, even if the stop position deviates due to step-out, disturbance, etc., it is treated as having completed a predetermined movement operation, which reduces the control accuracy of the gear ratio. There was a problem.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention, as shown in the basic configuration diagram of FIG. A maximum deceleration position detector provided at a maximum deceleration position of the continuously variable transmission mechanism in a continuously variable transmission that performs a speed change operation by open-loop control of the continuously variable transmission mechanism by a control means;
It is characterized by comprising a correction means for correcting the control origin of the control means based on the detection signal of the maximum deceleration position detector.

[Effect]

This invention performs highly accurate gear ratio control by correcting the control origin using a correction means based on a detection signal from a maximum deceleration position detector provided at the maximum deceleration position of a continuously variable transmission mechanism. When used as a transmission, the continuously variable transmission mechanism is controlled to the maximum deceleration position when the vehicle starts, so the control origin can be corrected each time the vehicle starts.

〔Example〕

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

2 to 4 are diagrams showing an embodiment in which the present invention is applied to a toroidal continuously variable transmission.

First, to explain the configuration, in FIG. 2, T is a toroidal continuously variable transmission as a continuously variable transmission, and C is a control device.

The toroidal continuously variable transmission T has an input disk 2 and an output disk 3 coaxially opposed to each other and pivotally mounted in a housing 1. The input disk 2 and the output disk 3 have the same shape and are arranged line-symmetrically, and are formed into toroidal surfaces such that their opposing surfaces cooperate to form a semicircle when viewed in axial cross section. A pair of power rollers 4 and 5 are rotatably disposed in a toroidal cavity formed by the toroidal surfaces of the input disk 2 and the output disk 3, and are in rolling contact with both the disks 2 and 3. . In this case, the power rollers 4, 5 are rotatably pivoted to the trunnions 6, 7, and supported so as to be tiltable about a pivot axis O that is the center of the toroidal surfaces of the input disk 2 and output disk 3.

A viscous material with high frictional resistance is applied to the contact surfaces between the input disk 2 and output disk 3 and the power rollers 4 and 5, so that the rotational force input to the input disk 2 is transferred to the power rollers 4 and 5. The change in the transmission ratio, that is, the gear ratio, causes the trunnions 6 and 7 to move a minute distance in the direction of the pivot axis O-O, thereby changing the tilt angle θ of the power rollers 4 and 5. It is done by folding. In this case, the movement of the trunnions 6 and 7 is controlled by the hydraulic cylinders 9a to 9d provided at both ends of the trunnions 6 and 7, the spool control valve 10 that controls the hydraulic pressure supply to these hydraulic cylinders 9a to 9d, and the trunnions 6. The moving mechanism 12 is controlled by a moving mechanism 12 that includes a precess cam 11 that is integrally formed.

The spool control valve 10 includes a valve body 10e having an inlet port to which the fluid supply pipe 10a is connected, an outlet port to which the distribution pipes 10b and 10c are connected, and a discharge port to which the fluid discharge pipe 10d is connected;
This valve body 10e has a vertically slidable spool 10f inside the valve body 10e, and the valve body 10e is a support 10 implanted on the outer surface of the housing 1 of the continuously variable transmission T.
g is biased upward by a return spring 10h, and is arranged to be slidable in the vertical direction by rotating a screw 13 parallel to the support column.

Further, the spool 10f is engaged with the cam surface of the precess cam 11 via the engagement roller 10i, and is moved up and down in accordance with the rotation of the trunnion 6. The trunnion 6, precess cam 11, and spool 10f constitute a mechanical feedback means.

Further, around the precess cam 11, there is a maximum speed increase position detector 11U configured with a micro switch, for example, for detecting the maximum speed increase position of the power rollers 4, 5.
and a similar maximum deceleration position detector 11L for detecting the maximum deceleration position of the power rollers 4 and 5,
A contact 11T provided on the precess cam 11 for these
are configured so that they come into contact with each other.

Further, the distribution pipe 10b is connected to the fluid pressure cylinders 9b and 9c, and the distribution pipe 10c is connected to the fluid pressure cylinders 9a and 9d, respectively.

Then, the spool control valve 10 is connected to the valve body 1
0e is connected to the pulse motor 12 via a transmission means 13 such as a screw that converts rotational force into linear driving force, and the valve body 10 is connected to the pulse motor 12 in accordance with the rotation of the pulse motor 12.
It is controlled by moving e up and down against the return spring 10h.

In addition, 14 is a vehicle speed detector that detects the rotation speed of the output disk 3 and outputs a detection signal corresponding to the vehicle speed, 15 is a throttle opening detector, 16 is a powerful/economy mode selection switch, and 17 is a shift position detector. It is.

The control device C includes an input amplifier 18, a control means 19, and a correction means 20, to which various detection signals are supplied as speed change control information serving as a reference for speed ratio selection.

As shown in FIG. 3, the specific configuration of this control device C includes the input amplifier 18 and the control means 1.
9, a microcomputer 21 constituting the correction means 20, and a pulse distribution circuit 22 that drives the pulse motor 12.

The input amplifier 18 is supplied with a throttle opening detection signal U from the outside, which serves as a reference for selecting a gear ratio, and a detection signal V from the vehicle speed detector 14 of the toroidal continuously variable transmission T, as shift control information, and uses these signals as shift control information. Amplify and output the value.

The microcomputer 21 is configured to include, for example, at least an interface circuit 23, an arithmetic processing unit 24, and a storage device 25, and executes predetermined arithmetic processing based on various input signals supplied to the interface circuit 23 to obtain a target. The operation amount L is calculated, the number of operation pulses corresponding to this is calculated, and the drive control signal CS which distributes the pulses to drive the pulse motor 12 is output from the interface circuit 23, and the maximum deceleration detector 11L outputs the drive control signal CS which drives the pulse motor 12. When the detection signal is input, the control origin, ie, spool valve 1
The deviation between the maximum deceleration position of 0 and the start of control by the control means 19 is corrected.

The interface circuit 23 has A/D conversion and its D/A conversion functions, and has an external shift position detection signal S, a powerful economy mode selection signal M, and an output signal OA of the input amplifier 18 on its input side. Detection signals AL and BL of the maximum acceleration position detector 11U and maximum deceleration position detector 11L are supplied, and a pulse distribution circuit 22 for driving the pulse motor 12 is connected to the output side.

The arithmetic processing unit 24 includes an interface circuit 23
storage device 25 in advance based on the input signal supplied to
The pulse motor 1 executes arithmetic processing according to a predetermined processing program stored in the , and finally drives the trunnions 6 and 7 of the toroidal continuously variable transmission T.
2 drive control signal CS is output.

The storage device 25 stores a processing program necessary for the arithmetic processing of the arithmetic processing device 24, and also stores angle type constants required in the processing process of the arithmetic processing device 24. 24
The processing results of the processing process are sequentially stored.

Next, the processing procedure of the arithmetic processing unit 24 will be explained with reference to FIG.

That is, when the power is turned on, initialization is first performed in step, then various detection signals and shift position detection signal S etc. from the input amplifier 18 are read in as shift control information in step, and then the shift is transferred to step and read as shift control information. Based on the predetermined shift control information stored in the storage device 25 in order to calculate the shift operation amount to be controlled to a predetermined gear ratio.
Select the shift operation amount conversion storage table.

Next, the process moves to step and calculates the gear change target value Er with reference to the selected storage table.

Next, the process moves to step, and it is determined whether or not the above-mentioned shift target value Er is the maximum deceleration position B.
When Er=B, the process moves to step.

In this step, the maximum deceleration position detector 11
Read the L detection signal BL, which is the logical value “1”
It is determined whether the logical value is "1" or not, and if the logical value is "1", the process moves to step.

In this step, the operation amount L of the pulse motor 12 is set to zero, and this is updated and stored in the operation amount storage area of the storage device 25.

Next, the process moves to step, where the maximum deceleration position B of the pulse motor 12 is updated and stored as the current position P in the current value storage area of the storage device 25, and then the process moves to step.

Also, when Er>B at the step,
Shifting to step, the pulse motor 12 is set based on the target value Er and the current tilt angle θ of the power rollers 4 and 5.
The operation amount L of the pulse motor 12 is calculated, updated and stored in the operation amount storage area of the storage device 24, and then the process moves to step, and the current position P of the pulse motor 12 is stored in the storage device 24.
The target position P ₀ is calculated by adding the operation amount L to the target position P 0 , and the target position P 0 is updated and stored in the current position storage area of the storage device 25 before proceeding to step.

Furthermore, the maximum deceleration position detector 11 is
When the L detection signal BL has a logical value of “0”,
Proceeding to step a, the pulse motor 12 is driven to force the power rollers 4 and 5 to the maximum deceleration position B, and the maximum deceleration direction value Bmax is updated and stored in the motion amount storage area of the storage device 25 as the motion amount L. Then move on to the step.

In the step, the number of operation pulses of the pulse motor 12 is calculated by referring to the memory table based on the operation amount L stored in the operation amount storage area, and this is temporarily stored in a predetermined storage area of the storage device before proceeding to the step. Then, the number of operation pulses is loaded into an operation pulse counter formed in a predetermined storage area of the storage device 25.

Next, the process moves to step 1, in which the distribution counter in the pulse distribution circuit 22 is reset, and then the process moves to step 3, in which the operating pulse is outputted to the pulse distribution circuit 22.

Next, the process moves to step, where the operating direction of the trunnions 6 and 7 is determined, and if this is the speed increasing direction, the process moves to step.

In this step, the maximum speed increase position detector 11
By reading the detection signal AL from U and determining whether this is the theoretical value "1", it is determined whether the power rollers 4 and 5 have reached the limit position on the speed increasing side, and the limit position is determined. If this is the case, the process moves to the step.

In this step, the operation pulse number counter 25a is counted down by "1", and then the process moves to the step where the operation pulse number counter 25a is counted down by "1".
Determine whether the count value of a is zero. The determination in this case is to determine whether or not the trunnions 6 and 7 have reached the target position P ₀ calculated in the above step. When the trunnions 6 and 7 have reached the target position P ₀ , the process moves to step and the above series of steps are performed. After waiting for a delay time of about 1/5 of the operation time required for processing, the process returns to step.

Also, if the step judgment result is trunnion 6,
7 in the deceleration direction,
The power rollers 4 and 5 are read in the detection signal of the maximum deceleration position detector and judged whether it is the theoretical value "1" or not.
It is determined whether or not the motor has reached the limit position on the deceleration side, and if the limit position has not been reached, the process moves to the step described above, and when the limit position is reached, the process moves to the step and the pulse motor 12 is brought to an emergency stop. Then move on to the step.

Furthermore, when the determination result of the step reaches the limit position, the process moves to the aforementioned step.

Here, the processing from step to step corresponds to the correction means 20, and the processing from step to step to step to step corresponds to the control means 19.

Next, the effect will be explained. Assuming that the vehicle is now in a stopped state and the ignition switch is in the OFF state, the processing shown in FIG. 4 is not executed in the arithmetic processing unit 24 of the control device C in this state, T does not perform gear change operation.

When the ignition switch is turned on in this stopped state, the arithmetic processing unit 24
The process shown in the figure is executed, and initialization is first performed in the step.Assuming that the shift position detection signal S representing the neutral range is output at this time, in this state, the engine is in an idling state, and Since the clutch is in the OFF state and engine rotational force is not being transmitted to the input disk 2 of the continuously variable transmission T, and the accelerator pedal is in the released state, the arithmetic processing unit 24 of the control device C performs the processing shown in FIG. Since the vehicle speed is zero at , processing is performed using the target value as the maximum deceleration position.

That is, each detection signal U, V, S, P is read (step), and a predetermined shift information-operation amount conversion storage table is selected based on these (step). Next, a shift target value Er is calculated with reference to the selected memory table (step). At this time, since the vehicle speed is zero and the throttle opening is in the closed state, the shift target value Er is set to the maximum deceleration position B in preparation for starting the vehicle.

Therefore, the detection signal from the maximum deceleration position detector 11L is transferred from step to step.
It is determined whether BL is the logical value "1" or not, and it is assumed that the power rollers 4 and 5 are at the maximum deceleration position B and the precess cam 11 is at the rotational position corresponding to the maximum deceleration position. Since the maximum deceleration position detector 11L outputs a detection signal BL with a logical value of "1", the process moves to step 12, and the operating amount of the pulse motor 12 is set to "0", and this is stored in the storage device 2.
5 is stored in the motion amount storage area.

Next, the process moves to step "0" indicating that the current position is the maximum deceleration position B (control origin).
is updated and stored in the current position storage area of the storage device 25.

In this way, when the operation amount L stored in the operation amount storage area of the storage device 25 is "0", the number of operation pulses of the pulse motor 12 becomes zero when performing the pulse motor control processing from step onwards. , the pulse motor 12 is not driven to rotate and is maintained in a stopped state.

From this state, when the vehicle is started by, for example, selecting a drive range, depressing the accelerator pedal, and leaving the clutch in a half-clutch state, execution of the process shown in FIG. 4 is started, and the process moves to step The shift position detection signal S, the powerful/economy mode selection signal M, the throttle opening detection signal U due to the depression of the accelerator pedal, and the rotation speed detection signal V of the output disk 3 of the continuously variable transmission T are read. is temporarily stored in a predetermined storage area of the storage device 25 as shift control information.

Next, proceeding to step, the storage device 25 is
A predetermined shift control information-shift operation amount conversion storage table is selected based on the shift control information stored in .

Next, referring to the selected memory table, the trunnions 6 and 7 are moved to calculate a shift target value Er for controlling the tilt angle θ of the power rollers 4 and 5 (step).

Since the target value Er at this time exceeds the maximum deceleration value B since the vehicle is in the starting state, the target value Er and the current position stored in the current position storage area are transferred from step to step. A predetermined pulse motor operation amount L is calculated based on the difference value from the above value, and is updated and stored in the operation amount storage area of the storage device 25. Next, proceed to step and calculate the target value _P0 based on the current value P and the operation amount L,
This is stored as the current value P in the current value storage area of the storage device 25.

Thereafter, similarly to the correction process described above, the pulse motor 12 is driven to increase speed according to the operation amount stored in the storage device 25, and the toroidal continuously variable transmission T is controlled to a gear ratio according to the shift control information. Ru.

That is, in step, the number of pulses to be output to the pulse motor 12 is calculated based on the operation amount L, and then this is preset in the counter 25a formed in the storage device 25 (step), and at the same time, the counter in the pulse distribution circuit 22 is The pulse driving signal CS is outputted to the pulse distribution circuit 22 so as to move from the reset (step) to the step and operate the pulse motor 12.

Next, in a step, it is determined whether the tilting direction of the power rollers 4 and 5, that is, the continuously variable transmission T is on the speed increasing side or the decelerating side, and if it is on the speed increasing side, it is moved to the speed increasing side limit position in a step. It is determined whether or not the pulse motor 12 has reached the limit, and if it is before the speed increasing side limit operation position, it moves to step and counts down the counter 25a by "1", then moves to 4, and determines whether the operation of the pulse motor 12 has ended or not. This is determined by determining whether or not the count content of the counter 25a is zero or not, and since the counter 25a has just been set at this time, the process returns to the above step.
Returns the above behavior. When the count value of the counter 25a becomes zero, it is determined in step that the operation of the pulse motor 12 has ended, and the process moves to step, waits for a predetermined time τ, and then returns to step.

In this way, when the pulse motor 12 is agitated by a predetermined amount by the drive pulse signal CS, the suple control valve 10 is moved by the return spring 10 in accordance with the rotation.
h, and according to the movement, the fluid supply pipe 10a and the distribution pipe 10b are communicated with each other, whereby hydraulic fluid is supplied to the hydraulic cylinders 9b and 9c, and the trunnions 6 and 7 are moved up and down by a predetermined amount, respectively. Moving. By moving the trunnions 6 and 7 up and down,
The power rollers 4 and 5 start tilting toward the speed increasing side.
As the power rollers 4, 5 tilt, the trunnions 6, 7 also rotate, so the precess cam 11 rotates, the control valve roller 10i descends, and the spool 10f descends accordingly. When the power rollers 4 and 5 rotate to a predetermined tilt angle θ position, the distribution pipes 10b and 10c and the fluid supply pipe 10a are cut off by the spool 10f, and the movement of the trunnions 6 and 7 is stopped. . However, since the moving positions of the trunnions 6 and 7 are shifted from the neutral position, the power rollers 4 and 5 are further tilted in the speed increasing direction, and in this state, the spool 10f is further lowered. Therefore, the fluid supply pipe 10a and the distribution pipe 10c communicate with each other to supply working fluid to the hydraulic cylinders 9a and 9d, and the trunnions 6 and 7 move up and down in the opposite direction. Then, when the trunnions 6, 7 return to the predetermined neutral position, the tilting of the power rollers 4, 5 is stopped, and the spool 10f at this time is in a position where it communicates with the fluid supply pipe 10a and the distribution pipe 10b. , the trunnions 6 and 7 move beyond the neutral position to the deceleration side, and the power rollers 4 and 7 accordingly move to the deceleration side.
5 is tilted to the deceleration side, and the spool 10f is lowered via the precess cam 11. As a result, the trunnion 6, the precess cam 11, and the spool 10f form a mechanical feedback means, so that the tilt angle of the power rollers 4 and 5 is θ is controlled according to the operating position selected by the valve body 10e.

Furthermore, when the vehicle is decelerated from the running state to the stopped state, the current shift target value Er or the maximum deceleration position B is reached, so if the power rollers 4 and 5 have not reached the maximum deceleration position, the maximum Since the detection signal BL of the deceleration position detector 11L has a logical value of "0", in this case, the process moves from step to step a, and the operation amount L of the pulse motor 12 is determined.
The maximum value Bmax on the deceleration side is selected as the deceleration side, and this is updated and stored in the operation amount storage area of the storage device 25, and then the process moves to step.

In this way, when the motion amount L stored in the motion amount storage area of the storage device 25 is the maximum value Bmax on the deceleration side, the number of drive pulses corresponding to the motion amount Bmax is calculated in step, and the pulses are adjusted accordingly. The motor 12 is rotationally driven in the deceleration direction, the valve body 10d of the spool control valve 10 is moved upward, and the power rollers 4 and 5 are tilted to the maximum deceleration position. Then, as the power rollers 4 and 5 tilt, the precess cam 11 rotates, and when the power rollers 4 and 5 reach the maximum deceleration position, a detection signal BL with a theoretical value of "1" is output from the maximum deceleration position detector 11L. be done. Therefore, moving from step to step,
The pulse motor 12 is brought to an emergency stop, and the power rollers 4 and 5 are stopped at the maximum deceleration position. As a result, the current position stored in the current position storage area of the storage device 24 matches the positions of the power rollers 4 and 5, and the correction of the control origin is completed.

In addition, in the above embodiment, the trunnion 6,
7 is moved in the axial direction using the hydraulic cylinders 9a to 9d, but the invention is not limited thereto. Of course, the present invention can also be applied to a type in which the trunnion is directly moved using a rotationally driven screw.

In addition, in the above embodiment, the case where the present invention is applied to a toroidal type continuously variable transmission as a continuously variable transmission has been described, but the present invention is not limited to this. In continuously variable transmissions, the gear ratio can be changed steplessly by wrapping a belt around the belt and changing the contact position between the belt and the pulley. When performing control, the maximum deceleration position is detected by the maximum deceleration position detector, and the control origin is corrected by the correction means based on the detected signal, thereby obtaining the same effect as in the above embodiment. [Effects of the Invention] ] As explained above, according to the present invention, the maximum deceleration position of the continuously variable transmission is detected by the maximum deceleration position detector, and the control origin is corrected by the correction means based on the detection signal. Therefore, the control accuracy when performing open-loop control can be greatly improved, and since the control origin is corrected at the maximum deceleration position of the continuously variable transmission, for example, when using the continuously variable transmission for a vehicle. In addition, the control origin can be corrected every time the vehicle stops, resulting in the effect that the vehicle's gear shifting operation can be performed reliably.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram showing an overview of this invention, FIG. 2 is a schematic configuration diagram showing an embodiment of this invention, and FIG. 3 is a block diagram showing an example of a control device applicable to this invention. FIG. 4 is a flowchart showing the processing procedure of the control device. 1...Housing, 2...Input disk, 3...
...Output disk, 4, 5...Power roller, 6,
7... Trunnion, T... Toroidal continuously variable transmission, C... Control device, 10... Spool control valve,
11... Precess cam, 12... Pulse motor,
14... Vehicle speed detector, 15... Throttle opening degree detector, 16... Powerful/economy mode selection switch, 18... Input amplifier, 19... Control means, 20... Correction means, 21... Microcomputer, 22...Pulse distribution circuit, 23...Interface circuit, 24...Arithmetic processing unit, 25...
…Storage device.

Claims (1)

[Claims] 1. In a continuously variable transmission that performs a speed change operation by open-loop control of a continuously variable transmission mechanism by a control means based on speed change control information from a speed change control information detection means that detects speed change control information such as a throttle opening command signal, The invention is characterized by comprising a maximum deceleration position detector provided at the maximum deceleration position of the continuously variable transmission mechanism, and a correction means for correcting the control origin of the control means based on the detection signal of the maximum deceleration position detector. Speed change control device for gear transmission.