JP3446389B2 - Transmission control device for automatic transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission, and more particularly to a shift control device useful for a toroidal type continuously variable transmission.

[0002]

2. Description of the Related Art A toroidal type continuously variable transmission is usually disclosed in, for example, Japanese Patent Application Laid-Open No. 58-54262 or Japanese Patent Application Laid-Open No. 3-2880.
It is configured as described in Japanese Patent Publication No. 62-62, and as schematically shown in FIGS. The toroidal type continuously variable transmission in these figures is a toroidal transmission unit including coaxially arranged input / output cone disks 1 and 2, and a power roller 3 for transferring power by frictional engagement between the input / output cone disks, And a shift control device as described below.

The power roller 3 is squeezed between the input / output cone disks 1 and 2 by the thrust corresponding to the input torque of the transmission, and the oil film is sheared between the power roller 3 and the input / output cone disks 1 and 2. The power roller 3 transmits power between the input / output cone disks 1 and 2. That is, the rotation of the input cone disc 1 is transmitted to the power roller 3 by the shear of the oil film, and the rotation of the power roller 3 is transmitted to the output cone disc 2 by the shear of the oil film, and conversely from the output cone disc 2 to the input cone. The power transmission to the disk 1 is similarly performed via the power roller 3.

The shift control device will now be described. It has an actuator (hereinafter referred to as a step motor) 4, and the step motor is given a shift command value (step number) corresponding to a target gear ratio. Is driven to the corresponding position,
Of the inner and outer valve bodies 5a and 5b of the shift control valve 5, the outer valve body 5b
Is displaced relative to the inner valve body 5a from the neutral position to open the shift control valve 5. As a result, the input hydraulic pressure to the shift control valve 5 is supplied to the chamber on one side of the piston 6 and the chamber on the other side is drained, so that the piston 6 displaces the power roller 3 in the vertical direction in the figure by fluid pressure. Let Thus the power roller 3, the rotation axis O ₁ is offset in the corresponding direction from the position shown in FIG. 11 which intersects the rotational axis O ₂ of the input and output cone discs 1 and 2, the power roller 3 by the offset y is output cone The component force from the discs 1 and 2 causes it to tilt (φ) around a swing axis O ₃ orthogonal to its own rotation axis O ₁ and the arc diameter of the frictional contact of the power roller 3 with respect to the input / output cone discs 1 and 2. R1, R2 (Fig. 1
(See 2) continuously changes, and continuously variable transmission can be performed.

When the power roller target tilt angle corresponding to the above-mentioned gear shift command value (target gear ratio) is achieved by such continuously variable gear shifting, the offset cam (y) and tilt (φ) of the power roller 3 are adjusted to the precess cam 7. And the inner valve body 5a of the shift control valve 5 fed back via the shift link 8 is
The power roller 3 returns to the initial neutral position by following the displacement (x) relative to the outer valve body 5b, and at the same time, the rotation axis O _{1 of} the power roller 3 intersects with the rotation axes O ₂ of the input / output cone disks 1 and _2. By returning to the illustrated position, the achievement state of the power roller target tilt angle corresponding to the gear shift command value (target gear ratio) can be maintained.

As described above, according to the gear shift principle in which the offset of the power roller 3 causes the tilt, the gear ratio can be changed at an extremely high speed, which is the greatest feature of the toroidal type continuously variable transmission.

On the other hand, however, since the power roller offset amount is minute, it is difficult to accurately bring the gear ratio to the target value, and it is necessary to improve the gear shift control accuracy in the automatic transmission. It is also a supreme proposition. On the other hand, in the above speed change control, the rotational speed of the input / output cone disk is detected, the actual power roller tilt angle φ is calculated from the actual speed ratio obtained from these ratios, and this is fed back to obtain the power roller target tilt angle. The comparison with the turning angle contributes to the shift control, but at this time, accurate detection of the input / output cone disc rotation speed can also help to improve the precision of the shift control.

At this time, it is possible to directly detect the actual tilt angle φ of the power roller with a potentiometer or the like, but it is more reliable than the method of calculating the actual tilt angle of the power roller from the detected value of the input / output cone disk rotation speed. It has been confirmed that it is not practical and is impractical for configuration reasons.

By the way, as a system for detecting the rotation speed of the input / output cone disk, a common sense rotation speed detection system as shown in FIG. 14 can be considered. That is, one or a plurality of through holes 403 are formed on the same circumference in the disk 402 coupled to the rotating body 401 whose rotation speed is to be detected, and are arranged on both sides of the disk 402 to form a light emitting device. 404 and the light receiving element 405 are installed opposite to each other. Then, the light emitting element 404 and the light receiving element 405 are arranged within the rotation locus of the through hole 403, and a light beam from the light emitting element 404 is aligned each time the through hole 403 is aligned with the light emitting element 404 and the light receiving element 405 as the disc 402 rotates. 1 reaches the light receiving element 405, and
As shown in FIG. 5, pulse signals are output one by one.

FIG. 1 shows such a rotation speed detection system.
As shown in FIG. 5, the time interval (pulse interval) T between adjacent pulse signal generation instants A and B is measured by the input capture function of the microcomputer, or the number of pulse signals within a fixed time is counted up. The rotation speed of the rotating body 401 can be detected.
It should be noted that today's microcomputers can realize such a rotation speed detection system because a high-speed and highly accurate coefficient can be obtained by crystal transmission.

[0011]

However, as described above, in the rotation speed detection system for generating the number of pulse signals according to the rotation speed, the number of pulse signals is low when the rotation speed is low.
As shown in (a), there are cases where the number of pulses is too small to receive a plurality of pulses during a constant calculation period ΔT of the microcomputer, and the rotation speed may be impossible to detect or may be inaccurate. . In particular, in the case of high-speed shift control such as the above-mentioned toroidal type continuously variable transmission, the above-mentioned problem becomes more remarkable because the calculation cycle ΔT of the microcomputer is also short.

In solving this problem, it is conceivable to increase the number of through holes 403 provided in the disc 403 so that the number of pulses per rotation increases as shown in FIG. 16 (b), but in this case, When the rotating body 401 rotates at high speed, the number of pulses becomes very large. This is
This means that the interrupt operation by the input capture function of the microcomputer occurs frequently, and a high-speed microcomputer capable of processing this interrupt operation during the operation cycle ΔT is required, which is not only expensive but also the existing microcomputer. It may be impossible to deal with it.

[0013] The present invention may be provided different multiple rotation detection means of the signal generation number even under the same rotation, so as not to produce the above problems even under rotational speed of any automatic transmission The purpose is to

[0014]

To this end, the shift control device for an automatic transmission according to the first aspect of the present invention is capable of slip control.
With an input shaft to which the engine rotation is input through a flexible joint
The automatic transmission that contributes to the speed change control of the input shaft rotation
The configuration is characterized by the following means.

That is, the engine speed detecting means for generating the number of signals corresponding to the number of rotations of the engine and the number of signals for the number of rotations of the input shaft are generated. Input shaft speed detecting means for generating more signals than engine speed detecting means, joint operating state determining means for determining whether or not the joint is directly connected between the input and output elements, and a signal from the means In response, while the joint is directly connected between the input / output elements, the signal from the engine speed detecting means is selected, and when the joint is not directly connected between the input / output elements, the input shaft rotation is selected. The automatic transmission is characterized in that the automatic transmission is provided with signal selecting means for selecting a signal from the number detecting means and contributing to the calculation of the rotation speed of the input shaft.

Further, a shift control device for an automatic transmission according to a second aspect of the invention is characterized in that the engine speed detecting means is an engine crank angle sensor.

In the shift control device for an automatic transmission according to the third aspect of the present invention, the joint operating state determining means determines whether the operating region of the engine is the operating region in which the input and output elements of the joint should be directly connected. It is characterized in that the joint is configured to determine whether or not the input / output elements are directly connected.

In the shift control device for an automatic transmission according to the fourth aspect of the present invention, the joint operating state determining means is configured to connect the input / output elements of the joint directly by a signal for controlling the direct connection between the input / output elements of the joint. It is characterized in that it is configured to determine whether or not there is.

In the shift control device for an automatic transmission according to the fifth aspect of the present invention, when the automatic transmission is a continuously variable transmission, when the input and output elements of the joint are directly connected, a signal from the input shaft speed detecting means is used. The direct-coupling shift control means for controlling the shift of the continuously variable transmission so that the input shaft rotational speed obtained by the above-mentioned method matches the engine rotational speed found by the signal from the engine rotational speed detecting means, and the direct-coupling shift control by the means When the above is completed, a direct connection timing control means for directly connecting the joint is additionally provided.

In the shift control device for the automatic transmission according to the sixth aspect of the present invention, the rotational speed of the input shaft is periodically calculated based on the signal from the input shaft rotational speed detecting means while the joint is in the direct connection state. Input shaft rotation speed calculation means and engine rotation speed calculation means for calculating the engine rotation speed based on a signal from the engine rotation speed detection means, and the input shaft rotation speed and the engine rotation speed calculated by these means are added. It is characterized in that a direct connection failure determining means for determining a direct connection failure of the joint from the disagreement is provided.

A shift control device for an automatic transmission according to a seventh aspect of the present invention responds to a signal from the direct connection failure determining means, and selects and inputs a signal from the input shaft speed detecting means when a direct connection failure of a joint occurs. The present invention is characterized in that a direct connection failure signal selecting means for calculating the shaft rotation speed is additionally provided.

[0022]

In the first aspect of the invention, the automatic transmission has slip control.
Input engine rotation through a possible coupling, said input shaft
The shift control is performed based on the rotation speed of.

By the way, the input that contributes to the shift control
To detect the shaft speed, check the engine speed.
The output means outputs the number of signals corresponding to the engine speed.
The input shaft rotation speed detection means responds to the rotation speed of the input shaft.
Generating the same number of signals.

In the signal selecting means, the joint is input / output.
Joint operating state to determine whether elements are directly connected
In response to the signal from the judging means, the signal is selected as follows.
Make a choice.

That is, the signal selecting means selects the signal from the engine speed detecting means while the joint is directly connected between the input / output elements , and the signal selecting means is connected while the joint is not directly connected between the input / output elements. A signal from the input shaft rotation speed detection means is selected, and the input shaft rotation speed is calculated based on this signal.

Therefore, the engine speed detecting means selected at the time of high rotation in which the joint is directly connected produces a small number of signals, and the input shaft speed detecting means selected at the time of low rotation in which the joint is not directly connected has the same rotation. Since more signals are generated than the above engine speed detection means under the conditions, the number of signals becomes insufficient and the calculation of the input shaft speed becomes inaccurate even in the non-direct connection state of the joint with the low input shaft speed. Even when the joint having a high input shaft rotation speed is directly connected, the number of signals does not become so large that an interrupt operation for calculating the input shaft rotation speed does not occur frequently.

Therefore, it is possible to detect the input shaft rotational speed with high accuracy in the entire rotational speed range of the input shaft.
The shift control based on this can also be made highly accurate, and the interrupt operation frequency for calculating the input shaft speed even under the direct coupling condition requires the use of an expensive microcomputer. Never get higher,
There is no increase in cost.

In the second aspect of the invention, the engine speed detecting means is an engine crank angle sensor. However, this engine crank angle sensor is indispensable for engine control and is existing in most engines. The structure of the second invention can be realized at low cost without newly installing the engine speed detecting means, and the cost can be reduced.

In the third aspect of the present invention, the joint operating state determining means determines whether or not the joint is directly connected between the input and output elements depending on whether or not the operating region of the engine is the operating region where the input and output elements of the joint should be directly connected. To determine. In this case, the existing material for determining whether or not the joint should be directly connected can be used as it is to determine the direct connection state of the joint, so that the determination can be realized at low cost and is economical.

In the fourth aspect of the invention, the joint operating state judging means judges whether or not the joint is directly connected between the input / output elements by a signal for controlling the direct connection between the input / output elements of the joint. In this case, since the existing determination result of whether or not the joint should be directly connected can be used as it is to determine the directly connected state of the joint, the determination can be realized at low cost and is economical.

In the fifth aspect of the invention, on the assumption that the automatic transmission is a continuously variable transmission, when the input / output elements of the joint are directly connected, the direct-connection shift control means is the input shaft rotational speed detection means. The speed change control of the continuously variable transmission is performed so that the input shaft speed obtained from the signal from the engine coincides with the engine speed obtained from the signal from the engine speed detecting means, and the speed change control during direct connection by the means is completed. At times, the direct connection timing control means causes the direct connection of the joint. In this case, the input shaft speed is surely matched with the engine speed when the joint is directly connected, and the direct connection shock of the joint in the continuously variable transmission can be reliably eliminated.

In the sixth aspect of the invention, while the joint is in the direct connection state, the input shaft rotation speed calculating means calculates the rotation speed of the input shaft based on the signal from the input shaft rotation speed detecting means, and The engine speed calculating means calculates the engine speed based on the signal from the engine speed detecting means. Then, the direct connection failure determination means determines the direct connection failure of the joint based on the mismatch between the input shaft speed and the engine speed calculated by these means. Therefore, it is possible to know the direct connection failure of the joint, and it is possible to eliminate the adverse effect of continuing the shift control of the automatic transmission without knowing the direct connection failure.

In the seventh aspect of the invention, the signal selection means for direct connection failure is responsive to the signal from the direct connection failure determination means.
When the direct connection failure of the joint occurs, the signal from the input shaft rotation speed detecting means is selected to calculate the input shaft rotation speed. Therefore,
Despite the direct connection failure of the joint and therefore the engine speed is not the same as the input shaft speed, the input shaft speed is calculated based on the signal from the engine speed detection means and the input shaft speed is calculated. It is possible to prevent the detection result of (1) from becoming illegal.

[0034]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 exemplify a toroidal-type continuously variable transmission equipped with a shift control device according to an embodiment of the present invention. FIG. 1 is a vertical cross-sectional side view of the toroidal-type continuously variable transmission, and FIG. FIG. Note that, for convenience, in these figures, the same parts as those in FIG. 12 are denoted by the same reference numerals.

First of all, the toroidal transmission unit will be explained. This is to convert the rotation from the engine E into the torque converter 7.
It has an input shaft 20 which is transmitted through
Form a transmission component in the present invention. Here, the torque converter 70 corresponds to a joint in the present invention, and a pump impeller 70a as an input element driven by an engine.
And a turbine runner 70b as an output element that is fluid-driven by the pump impeller 70a, and a working fluid that has collided with the turbine runner 70b.
A lock-up clutch 70 that directly connects the stator 70c as a reaction force element that returns to a to generate a torque increasing action, and the pump impeller 70a and the turbine runner 70b.
It is assumed that it is a well-known one consisting of d.

As shown in FIG. 1, the input shaft 20 rotatably supports an end portion far from the engine E in a transmission case 21 through a bearing 22, and a central portion thereof has an intermediate wall 23 of the transmission case 21. A bearing 24 and a hollow output shaft 25 are rotatably supported therein. The input and output cone disks 1 and 2 are rotatably supported on the input shaft 20, and the input and output cone disks are arranged so that the toroidal curved surfaces 1a and 2a face each other. A pair of power rollers 3 disposed on both sides of the input shaft 20 sandwiching the input shaft 20 are interposed between the toroidal curved surfaces of the input / output cone disks 1 and 2 which face each other.
The following configuration is adopted to pinch between them.

That is, the loading nut 26 is screwed into the bearing end portion of the input shaft 20, the cam disc 27 is retained by the loading nut, and is rotationally engaged with the input shaft 20, and the toroid of the input cone disc 1. The loading cam 28 is interposed between the curved surface 1a and the end surface far from the curved surface 1a,
The rotation from the input shaft 20 to the cam disk 27 is transmitted to the input cone disk 1 via the loading cam. Here, the rotation of the input cone disc 1 is transmitted to the output cone disc 2 via the rotation of the power roller 3, and during the transmission, the loading cam 28 generates a thrust proportional to the transmission torque, so that the power roller 3 is rotated by the input / output cone. A force is applied between the disks 1 and 2 to enable the above power transmission.

The output cone disk 2 is wedged on the output shaft 25, and the output gear 29 is fitted on this shaft so as to rotate integrally. The output shaft 25 is further rotatably supported in an end cover 31 of the transmission case 21 via a radial / thrust bearing 30. In the end cover 31, the radial / thrust bearing 3 is separately provided.
The input shaft 20 is rotatably supported via 2. here,
The radial and thrust bearings 30 and 32 are abutted against each other via a spacer 33 so that they cannot approach each other, and the relative thrust and thrust bearings 30 and 32 cannot move relative to each other. Make it urge in the direction. Thus, the thrust acting between the input / output cone disks 1 and 2 by the loading cam 28 is
The internal force that sandwiches 3 does not act on the transmission case 21.

Each power roller 3 is, as shown in FIG.
The trunnion 41 is rotatably supported, and the trunnion has an upper end rotatably and swingably at both ends of an upper link 43 by a spherical joint 42, and a lower end each having a spherical joint 44.
Thus, the lower link 45 is rotatably and swingably connected to both ends of the lower link 45. The upper link 43 and the lower link 45 are supported by the spherical joints 46 and 47 in the center of the transmission case 21 so as to be swingable in the vertical direction so that both trunnions 41 can be vertically moved in synchronization with each other in opposite directions. .

A shift control device for shifting gears by vertically moving both trunnions 41 in synchronism with each other in opposite directions will be described below with reference to FIG. Each trunnion 41 is provided with a piston 6 for individually stroking them vertically, and upper chambers 51, 52 and lower chambers 53, 54 are defined on both sides of both pistons 6, respectively. The shift control valve 5 is installed in order to control the strokes of both pistons 6 in opposite directions. Here, the shift control valve 5 includes a spool type inner valve body 5a and a sleeve type outer valve body 5b slidably fitted to each other, and the outer valve body 5b is attached to the valve outer casing 5a.
It is configured by slidably fitting to c.

In the shift control valve 5 described above, the input port 5d is connected to the pressure source 55, one communication port 5e is connected to the piston chambers 51 and 54, and the other communication port 5f is connected to the piston chambers 52 and 53, respectively. To do. And the inner valve body 5a
To cooperate with the cam surface of the recess cam 7 fixed to the lower end of one trunnion 41 via a bell crank type speed change lever 8 to drive the outer valve element 5b to the step motor 4 in a rack and pinion type drive engagement. .

The operation command for the shift control valve 5 is a shift command value U.
The actuator (step motor) 4 which responds to is given as a stroke to the outer valve body 5b via the rack and pinion. This operation command causes the outer valve body 5b of the shift control valve 5 to be displaced relative to the inner valve body 5a from the neutral position to, for example, the position shown in FIG. Is supplied to the chambers 52 and 53, while the other chambers 51 and 54 are drained, and the outer valve body 5b of the shift control valve 5 is displaced in the opposite direction from the neutral position relative to the inner valve body 5a. When the shift control valve 5 is opened, the fluid pressure from the pressure source 55 is supplied to the chambers 51 and 54, while the other chambers 52 and 54,
It is assumed that 53 is drained and both trunnions 41 are displaced by fluid pressure through the piston 6 in opposite vertical directions corresponding to each other in the figure. As a result, both power rollers 3 are
The rotation axis O ₁ is offset (offset amount y) from the illustrated position where the rotation axis O 1 intersects the rotation axes O ₂ of the input / output cone disks 1 and _2, and the power roller 3 is offset from the input / output cone disks 1 and 2 by the offset. With the swing component force of ( ₁ ), tilting (tilt angle φ) is performed around the swing axis O ₃ orthogonal to the own rotation axis O ₁ and continuously variable transmission can be performed.

During the shifting, the precess cam 7 coupled to the lower end of one trunnion 41 shifts the above-mentioned vertical movement (offset amount y) and tilt angle φ of the trunnion 41 and the power roller 3 via the shift link 8. Control valve 5
Is mechanically fed back to the inner valve body 5a. When the gear shift command value U to the step motor 4 is achieved by the continuously variable gear shift, mechanical feedback via the recess cam 7 causes the inner valve body 5a of the gear shift control valve 5 to move,
Return to the initial neutral position relative to the outer valve body 5b,
At the same time, both the power roller 3, by the rotation axis O ₁ returns to the illustrated position that intersects the rotation axis O ₂ of the input and output cone discs 1 and 2, it is possible to maintain the achieved state of the shift command value.

Since the purpose of the control is to set the power roller tilt angle φ to a value corresponding to the target gear ratio, the precess cam 7 basically needs to feed back only the power roller tilt angle φ. However, the reason why the power roller offset amount y is also fed back here is to provide a damping effect for preventing the shift control from becoming oscillating and to avoid the hunting phenomenon of the shift control.

The gear shift command value U to the step motor 4 is determined by the controller 61, which causes the controller 61 to output a signal from the throttle opening sensor 62 for detecting the engine throttle opening TVO and the output cone disc 2 output rotation sensor 63 that detects the rotational speed N _o
From the input rotation sensor 64 that detects the rotation speed N _i of the input cone disc 1 and the signal from the engine rotation sensor 65 that detects the engine rotation speed N _e .

The output rotation sensor 63 corresponds to a transmission rotation speed detecting means, and has a structure shown in FIG. 14 or a pulse gear and a pickup, and is provided in association with the output shaft 25 as shown in FIG. and it outputs a pulse signal of a number corresponding to the rotational speed N _o of the output cone disc 2. Further, the input rotation sensor 64 corresponds to the shift control rotation speed detecting means and the input shaft rotation speed detecting means, and has, for example, the structure shown in FIG. 14 or a structure including a pulse gear and a pickup, and as shown in FIG. Input cone disk 2 provided in association with 20
It is assumed that the number of pulse signals is output according to the rotation speed N _i . Further, the engine rotation sensor 65 corresponds to a shift control rotation speed detection means and an engine rotation speed detection means,
For example, the configuration shown in FIG. 14 or the configuration including a pulse gear and a pickup is provided in association with the engine driven pump impeller 70a as shown in FIG. 1, and outputs a number of pulse signals according to the engine speed N _e. It shall be.

Here, it is economically advantageous to use the existing crank angle sensor in the engine control system as the engine speed sensor 65, and it is economically advantageous to normally generate one or two pulse signals per engine revolution. It is a thing. On the other hand, the input rotation sensor 64 does not serve as a gear shift control rotation speed detecting means for generating a larger number of pulse signals than the engine rotation sensor 65 even under the same rotation speed. Rough rotation control rotation speed detection means that generates fewer pulse signals than the input rotation sensor 64 is used.

The controller 61 includes the sensors 62-
Based on the input information from 65, the shift control for determining the shift command value U to the step motor 4 is performed by the calculation described later,
Although the detailed description is omitted, the following lockup control is performed.

To briefly explain the lock-up control, since the automatic transmission is a toroidal type continuously variable transmission in this example, the torque converter 70 shown in FIG. 1 guarantees the idling operation of the engine when the vehicle is stopped. The torque converter 70 is provided only for the purpose of increasing the torque at the time of starting. Therefore, the torque converter 70 is input / output immediately after the completion of starting, that is, by engaging the lock-up clutch 70d in the low vehicle speed range where the output cone disk rotational speed N _o is low. It suffices if a lockup state is established in which elements are directly connected, and the controller 61
Although not shown, the lockup control is executed for the torque converter 70.

Next, the shift control will be described. For the shift control, the controller 61 includes a signal selecting section 61a corresponding to signal selecting means and a shift command value determining section 61b as shown in FIG. Signal selection unit 61a, one of the pulse signal from the pulse signal and the engine speed sensor 65 from the input rotation sensor 64 according to the output rotary output cone disk rotational speed detected by the sensor 63 N _o (vehicle speed),
That is, in the low vehicle speed range before the torque converter is locked up, a pulse signal from the input rotation sensor 64, which is the rotational speed detecting means for gear shift control, is used in the low vehicle speed range, and in the high vehicle speed range after the torque converter is locked up. Since the rotation speed N _e matches the input shaft rotation speed N _i , the pulse signal from the engine rotation sensor 65, which is a rough shift control rotation speed detection means, is selected. At the same time, the signal selection unit 61a calculates the rotation speed N _i (at low vehicle speed) or N calculated based on the pulse signal thus selected.
_It is assumed that _e (at high vehicle speed) is supplied to the shift command value determination unit 61b as the input shaft rotation speed N _I.

The gear change command value determiner 61b is a shift map the detected throttle opening TVO with sensor 62, and based on the vehicle speed can be seen from the detected output cone disk rotational speed N _o by sensor 63, is set in advance The target input shaft rotational speed is searched from the target input shaft rotational speed, and the target input shaft rotational speed is then divided by the output cone disk rotational speed N _o to calculate the target gear ratio, and the power roller target for achieving the target gear ratio. Calculate the tilt angle. In addition, the gear shift command value determination unit 61b uses the signal selection unit 61a to perform the actual gear shift represented by the ratio N _I / N _o of the input shaft rotation speed N _I and the output cone disc rotation speed N _o obtained as described above. The ratio is calculated, and the current actual tilt angle of the power roller is obtained from this actual gear ratio. Then, the shift command value determination unit 61b calculates the sum of the feedback control amount corresponding to the deviation between the power roller target tilt angle and the power roller actual tilt angle and the feedforward control amount corresponding to the power roller target tilt angle. Is used as the shift command value U, and the step motor 4 is commanded. Here, the step motor 4 can make the shift control valve 5 stroke according to the shift command value U to perform the shift described above.

By the way, in detecting the input shaft rotation speed N _I that contributes to the above-mentioned shift control, the torque converter is locked up (in the converter state).
In the low vehicle speed range, the input shaft rotational speed N _I is calculated based on the pulse signal from the input rotation sensor 64 that generates a relatively large number of pulses, and in the high vehicle speed range after the torque converter is locked up, the pulse generation number is generated. Since the input shaft rotation speed N _I is calculated based on the pulse signal from the engine rotation sensor 65 having a relatively small number of pulses, the number of pulse signals is insufficient and the input shaft rotation speed is low even when the vehicle speed is low and the input shaft rotation speed is low. The calculation of the rotation speed N _I does not become inaccurate or impossible, and when the vehicle speed is high and the input shaft rotation speed is high, the number of pulse signals is too large. Interrupt operations do not occur frequently. Therefore, the input shaft rotational speed N _I can be detected with high accuracy in the entire rotational speed range of the input shaft 20, and the shift control based on this can also be made highly accurate. Since the interrupt operation frequency is low even at the vehicle speed, the controller 61 may be inexpensive, and the above-described effects can be achieved without incurring a cost disadvantage.

When the controller 61 is composed of a microcomputer, this microcomputer executes the control program shown in FIG.
The operation by 1a and the shift command value determination unit 61b is performed.

In FIG. 3, first, initial setting is performed in step 110, and then, in step 111, interruption of the input captures 1, 2, 3 is enabled. Here, the signal line of the input capture 1 is connected to the engine rotation sensor 65, the signal line of the input capture 2 is connected to the input rotation sensor 64, and the signal line of the input capture 3 is connected to the output rotation sensor 63.

When the input capture 1 interrupt occurs, the interrupt process of FIG. 4 is executed, when the input capture 2 interrupt occurs, the interrupt process of FIG. 5 is executed, and when the input capture 3 interrupt occurs, the interrupt process of FIG. Interrupt processing is executed. In these interrupt processes, for each interrupt, a variable that stores the value of the previous capture register is stored in a different variable, and then the value of the capture register is stored in the source variable. This is a process of accommodating the value of the input capture register immediately before and the value of the immediately preceding input capture register in a predetermined variable.

In the next step 112 in FIG. 3, the difference V0− between the variables V0 and V1 substituted by the interrupt processing in FIG.
V1 is calculated to obtain the time interval of the pulse signal from the output rotation sensor 63, and from this, the output cone disk rotation speed N
Calculate _o and substitute in the variable OUTREV. Next, at step 113 corresponding to the joint operating state determination means, whether the variable OUTREV is smaller than a predetermined value corresponding to the vehicle speed at which the torque converter should be locked up is in the low vehicle speed range (the torque converter is in the converter state). (Whether in the high vehicle speed range where the torque converter is locked up) is determined.

When the torque converter is in the low vehicle speed range in which the converter is in the converter state, the interrupt of the input capture 2 is enabled and the processing of FIG. 6 is performed in step 114 corresponding to the signal selecting means, and the variables T0 and T1 are set. Execute rewriting. If it is determined in step 115 that the input capture 2 is interrupted more than once and the rotation speed can be calculated based on the pulse signal from the input rotation sensor 64, in step 116, the variable T0 related to the input capture 2 is changed. The difference T0-T1 between T1 is calculated to obtain the time interval of the pulse signal from the input rotation sensor 64, the input cone disk rotation speed N _i is calculated from this, and the result is substituted into the variable INPREV.

When the torque converter is in the high vehicle speed range where the torque converter is locked up, the step 113 selects the step 117 corresponding to the signal selecting means, where the interrupt of the input capture 2 (process of FIG. 6) is selected. Input capture 1 at step 118
The difference E0-E1 between the variables E0 and E1 related to
The time interval of the pulse signal from the engine rotation sensor 65 is obtained, the engine speed N _e is calculated from this, and the variable IN
Substitute in PREV.

Even when it is determined in step 115 that the input capture 2 has been interrupted less than twice, the above step 118 is executed. The reason is that if step 116 is executed at the time of the determination, the number of pulse signals from the input rotation sensor 64 is insufficient and the accurate rotation speed cannot be calculated.

Here, the variable INPREV in steps 116 and 118 is N shown in FIG. 2 in the above embodiment.
Represents the value of _{I. In} step 119, this variable INPR
The value in EV, divided by the value of the variable OUTREV (representing the output cone disk rotational speed N _o), calculates the actual speed ratio, the corresponding variable RA this
Store in TIO. Then, in step 120, the variable RA
The gear shift command value U is determined so that the value of TIO is brought to the target gear ratio, and is output to the step motor 4 to execute the gear shift as described above.

Also in this example, the variable INPR that contributes to the shift control
In determining the EV value (corresponding to the input rotation speed N _I in the above embodiment), the low vehicle speed range before the torque converter is locked up in step 113 or the high vehicle speed range after the torque converter is locked up. Determine whether
In the former low vehicle speed range, in step 116, the value of the variable INPREV is obtained based on the pulse signal from the input rotation sensor 64 with a relatively large number of pulse generations, and in the latter high vehicle speed range, step 118 compares the number of pulse generations. Variable INPR based on the pulse signal from the engine rotation sensor 65
Since the value of EV is obtained, the same operational effect as in the above embodiment can be achieved.

In the toroidal type continuously variable transmission,
The transmission input speed N _I (variable I
It is advantageous to use the same value for NPREV) and perform gear shift control during lockup as follows.

In the toroidal type continuously variable transmission, the lockup of the torque converter is performed at the low speed gear ratio immediately after starting as described above, and the shock at the lockup tends to be large. Lock Here, it is shown by reference rotation speed variation of each part at the time when the lock-up was carried out at comparable low-speed shift stage in the stepped automatic transmission, a lock-up initial instant t _1, as shown in FIG. 7 until up completion instant t _2, it is sharply reduced so that the engine speed N _e coincides with the transmission input rotational speed N _I, rotation change amount of energy at this time of the engine causes a large lock-up shock. Note that FIG. 7 shows the case where the gear ratio is 1 and the final gear ratio is 1 for the sake of simplicity.

In the case of a continuously variable automatic transmission including a toroidal type continuously variable transmission, when the torque converter is locked up with the gear ratio unchanged, the magnitude of the shock is the same.
Therefore, in this example, as shown in FIG. 8, which shows changes in the rotational speed of each part under the same conditions as in FIG. 7, the transmission input rotational speed N _I
Is changed over time (the wheel speed N _W is also shown), the shift control of the toroidal type continuously variable transmission is performed at the time of lockup. That is, although not shown, in step 120 of FIG. 3 corresponding to the direct-coupling shift control means and the direct-coupling timing control means, the transmission input rotational speed is changed from the lock-up start instant t ₁ to the lock-up end instant t _2. The gear ratio is changed so that N _I gradually matches the engine speed N _e , so that the transmission input speed N _I does not completely match the engine speed N _e at the lock-up end instant t ₂ . Therefore, we will eliminate the lock-up shock. Of course, the shift control thereafter is returned to the shift control based on the shift map described above.

However, since the shift control during lockup is a shift control in the low vehicle speed range (low rotation), it is essential to accurately detect the input rotation speed N _{I in} the low vehicle speed range (low rotation). However, according to the configuration of the present invention in which the input rotational speed N _I is detected by properly using the pulse signals from the sensors 64 and 65 as described above, the requirement regarding the detection accuracy can be sufficiently satisfied.

That is, in order to perform the shift-up control for lock-up described above with reference to FIG. 8, it is assumed that the lock-up operation is completed at a speed of 20 km / h, the vehicle is started at the minimum speed change ratio, and the speed is about 10 km / h. At the speed, the speed is changed smoothly toward the high speed side gear ratio, and immediately before the lockup operation, the speed is changed again toward the low speed side gear ratio.
Gear ratio control of the procedure of raising _I is necessary,
As a result, the lock-up vehicle speed is 20
In the low vehicle speed range up to km / h, highly accurate input rotation speed measurement is required. According to the present invention, this requirement can be satisfied.

Under the conditions of a speed of 11.3 km / h, a final gear ratio of 3, and a tire diameter of 60 cm, the output disk rotation speed N _O is 5 rotations per second. If the gear ratio is 1: 1, the input disk rotation speed N _I is also 5 rotations per second, and if the control cycle of the controller 61 is 10 ms, two pulses can be reliably detected within one control cycle. That is, if 200 pulses / second are to be realized,
The sensor for detecting the rotation speed needs to output 40 pulses per rotation.

When the speed reaches 135 km / h under the same conditions such as the final gear ratio and the low gear condition with the gear ratio of 2: 1 under the condition of 40 pulses per rotation, the input disk rotation speed N _I is 120 rotations / second. , 7200r
pm, and the controller 61 is interrupted 4800 times per second.

If 50 μs is required for one interrupt processing, 4800 interrupts per second will result in 240 m / s.
Seconds are required, which is 24% of the total processing time. However, if the torque converter is locked up at a speed of 135 km / h, the engine rotation sensor 65 with one rotation and two pulses is switched to, the measurement based on the input rotation sensor 64 is not performed, and therefore the interrupt processing is not performed. For example, the number of interrupts at 135 km / h is 240 times per second, and the interrupt processing time is 1 per second.
The load on the controller 61 is dramatically reduced because the load is reduced to 2 ms.

In the low vehicle speed range, interruptions are frequently made in any case.
Since the degree is low, the engine speed N _e, Input shaft speed N
_iEven if you measure simultaneously, the microcomputer system
Does not become a big load of.

When the control cycle is set to 1 msec, the sensor for detecting the number of revolutions needs a pulse number of 400 pulses / revolution, and the interruption is 48,000 times per second, and the output revolution number N _o is measured. Similarly, when a sensor for detecting the number of rotations of 400 pulses per rotation is used, the number of interrupts becomes 96000, and if the interrupt processing time is 10 μsec or less,
Interruption processing itself of 96000 times per second becomes impossible, and it becomes difficult to control the toroidal type continuously variable transmission even when the high-speed controller 61 is used.
The effectiveness of the present invention is further enhanced.

Further, the frequency measurement method for counting the number of pulses per predetermined time is not the period measurement for measuring the time interval of the pulse for the rotation speed measurement, but the control for 10 msec is performed in the low vehicle speed region of 5 revolutions / second. The minimum number of pulses to ensure 1% resolution within a cycle is 100 pulses in 10 msec, that is, 2000 pulses are required for one rotation, and 2 pulses are required for one rotation.
The sensor for detecting the number of revolutions that outputs 000 pulses is much more complicated and more accurate than the sensor for detecting the number of revolutions that outputs 40 pulses per revolution, and the above-mentioned speed of 135 km / h.
Under the condition of / h, the frequency measurement is 240 kHz,
From the viewpoints of cost and mechanical reliability, circuits with good high-frequency characteristics, transmission means, and noise countermeasures are required. The method is superior, and even in the frequency measurement method, switching of a plurality of rotation speed measurement devices is desired.

If the method for measuring the period is 1 MHz
Using a microcomputer internal clock of 5 rpm / sec at a speed of 5 revolutions / sec, a time measurement of 5 msec is performed with a minimum resolution of 1 μsec.
The minimum resolution for the measurement time is 0.02%, which is 12
At a speed of 0 revolutions / sec, a 2-pulse output revolution speed measuring device gives a value of 4.166 msec, that is, a minimum resolution of 0.024% with respect to the measurement time.

FIG. 9 shows another example of the present invention in which steps 121 to 128 are added to FIG.
After the processing of 0, the timer Timer which is incremented in step 121 is set. Then, in step 113, it is determined that the vehicle is in the lockup state (high vehicle speed range), and the variable INPREV is determined based on the pulse signal from the engine rotation sensor 65.
While the (transmission input rotation speed) is being obtained, every time it is determined in step 122 that the timer Timer has reached a predetermined value, that is, every time a predetermined time elapses, control is performed in step 12
Branch into a loop of 3 to 127.

First, in step 123, step 1
The interrupt of the input capture 2 which has been prohibited in 17 is permitted, and then the difference E0-E between the variables E0 and E1 in step 124 corresponding to the engine speed calculating means.
1 is calculated to obtain the time interval of the pulse signal from the engine rotation sensor 65, the engine speed N _e is calculated from this, and the result is substituted into the variable INPREV. Next, in step 125 corresponding to the input shaft rotation speed calculation means, the difference T0-T1 between the variables T0 and T1 relating to the input capture 2 for which interrupt is permitted in step 123 is calculated, and the difference from the input rotation sensor 64 is calculated. The time interval of the pulse signal is obtained, the input shaft rotation speed N _i is calculated from this, and the variable INP
Substitute in REV2.

In the next step 126, the timer T
reset the imager to 0, which causes step 122
However, a branch to a loop including steps 123 to 127 is performed every predetermined time described above. Then step 1
In step 27, it is determined whether the deviation between the variables INPREV and INPREV2 substituted in steps 124 and 125, that is, the deviation between the engine speed N _e and the input shaft speed N _i is smaller than a predetermined value. Since now the torque converter is locked-up state, the engine speed N _e and the input shaft rotational speed N _i should match, between the engine speed N _e and the input shaft rotational speed N _i in step 127 When it is determined that the deviation is larger than a predetermined value, it can be considered that a lockup failure has occurred. Therefore, step 127 corresponds to the direct connection failure determination means.

If the lockup is not defective, the control is returned to step 119 and the same control as in FIG. 3 is continued. However, if it is determined that the lockup is defective, the pulse from the engine rotation sensor 65 is output in step 118. Since the engine speed N _e obtained based on the signal does not match the transmission input speed even in the lock in the lockup region, step 12 corresponding to the signal selection means for direct connection failure
In step 8, the following abnormality processing is performed. That is, step 128
Then, an abnormal alarm for notifying the lock-up failure is issued, and at the same time, the shift control is switched to a shift control with a long control cycle using the input shaft rotation speed N _i obtained based on the pulse signal from the input rotation sensor 64, and thereafter this shift control is performed. Let it continue.

According to the structure of this example, the engine speed N _e obtained based on the pulse signal from the engine speed sensor 65 does not match the transmission input speed due to the lockup failure. Instead, it is possible to avoid the adverse effect that the engine speed _Ne is continuously regarded as the transmission input speed and inaccurate shift control is performed.

FIGS. 10 and 11 show still another example of the present invention. In this example, as is clear from FIG. 10 which schematically shows the toroidal type continuously variable transmission, as shown in FIG. A lockup state determiner 71 corresponding to the joint operation state determination means is added, and the signal selection unit 61a performs the same signal selection as in each of the embodiments according to the lockup state determination signal L / U. To do. Here, it is assumed that the lockup state determiner 71 detects an electric signal such as a pressure signal or a duty value that controls lockup, and outputs a signal L / U having a level corresponding to the electric signal to the signal selection unit 61a.

In the case where the controller 61 is constituted by a microcomputer in this example, the shift control program executed by the microcomputer is as shown in FIG. 11, and this program adds step 129 after step 112 in FIG. The step 113 is replaced with the step 130.

At step 129, the signal L / U from the lockup state determiner 71 is read, and this is read as the variable RO.
It is accommodated in KUP. Next, at step 130, it is determined whether the torque converter is in the converter state (low vehicle speed range) or not (whether the torque converter is in the high vehicle speed range where the lockup state is set), depending on whether the variable ROKUP is smaller than a predetermined value.
To judge. If the torque converter is in the low vehicle speed range where the converter is in the converter state, the control proceeds to step 114 and subsequent steps. If the torque converter is in the high vehicle speed range where the torque converter is in the lockup state, the control is advanced to step 117 and subsequent steps. The shift control similar to that described above is executed.

In this example, since the lockup state of the torque converter is detected by using the existing pressure signal for controlling the lockup and the electric signal such as the duty value, the detection can be performed at a low cost. Further, when the lockup region is defined only by the vehicle speed as in the above-mentioned embodiment, there is no problem, but when the lockup region is defined by a combination of a plurality of factors such as the throttle opening and the vehicle speed, When trying to detect the lockup state of the torque converter by the lockup area determination as in the above embodiment, the determination becomes complicated, but in this example, the lockup state is detected by checking only the signal that governs the lockup. Therefore, the complexity can be eliminated.

Although the speed change control device of the present invention is applied to the toroidal type continuously variable transmission in each of the above-described embodiments, the idea of the present invention is based on another continuously variable transmission such as a V-belt type continuously variable transmission. Needless to say, the present invention can be applied not only to a continuously variable transmission but also to a stepped automatic transmission. Also,
The case where the joint is the lock-up type torque converter 70 has been described above, but the concept of the present invention is also applicable to a case where a slip control mechanism is added to a fluid coupling having no torque increasing function, an electromagnetic clutch, or the like. It can be applied similarly.

[0084]

As described above, the shift control device for an automatic transmission according to the first aspect of the present invention has the slip control according to the first aspect.
Input engine rotation through a possible coupling, said input shaft
Shift Control of Automatic Transmission Controlled by Gear Speed
The device is as follows. First, the above shift control
When detecting the rotation speed of the input shaft that contributes to
According to the engine speed from the gin speed detection means
The number of signals is generated, and the input shaft rotation speed detection means
The number of signals is generated according to the rotation speed of the input shaft.

The signal selecting means is such that the joint is between the input and output elements.
A joint operating state determination hand that determines whether or not the
In response to the signal from the stage, the joint directly connects the input and output elements.
The number of signals generated is small even under the same rotation conditions during
Select the signal from the engine speed detection means and repeat it.
While the hand is not directly connected between the input and output elements
Even if the number of signals generated is large, the input shaft rotation speed detection means
Signal from the above and based on the selected signal,
Calculate the rotation speed.

Therefore, based on a small signal from the engine speed detecting means when the joint is in the direct connection state at high speed, and based on a large signal from the input shaft speed detecting means when the joint is in the low speed state where the joint is not directly connected, Since the input shaft speed is calculated, even if the joint with a low input shaft speed is not directly connected, the number of signals will not be sufficient and the input shaft speed calculation will not be inaccurate or impossible. Further, even when the joint having a high input shaft rotational speed is directly connected, the number of signals does not occur so much that an interrupt operation for calculating the input shaft rotational speed does not occur frequently.

Therefore, the input shaft rotational speed can be detected with high accuracy in the entire rotational speed range of the input shaft.
The shift control based on this can also be made highly accurate, and the interrupt operation frequency for calculating the input shaft speed even under the direct coupling condition requires the use of an expensive microcomputer. Never get higher,
There is no increase in cost.

[0088] transmission control system for an automatic transmission according to the second invention, as described in claim 2, since the said engine speed detecting means configured to engine crank angle sensor, engine crank angle sensor, engine Since it is indispensable for the control of and is already existing in most engines, the configuration of the above-mentioned second invention can be realized at low cost without newly installing the engine speed detecting means,
The cost can be reduced.

[0089] shift control device for an automatic transmission according to the third invention, as described in claim 3, said joint activated by whether or not the engine is in the operating region to be connected directly between the input and output elements of the joint Since the state determination means is configured to determine the direct connection between the joint input / output elements, the existing material for determining whether or not the joint should be directly connected can be used as it is to determine the direct connection state of the joint. The determination can be realized at low cost, which is economical.

[0090] shift control device for an automatic transmission according to the fourth invention, as described in claim 4, the joint actuation judging means, between coupling input and output elements by a signal for controlling the direct between input and output elements of the joint Since the direct connection state of the joint is determined, the existing determination result of whether or not the joint should be directly connected can be used as it is to determine the direct connection state of the joint, so that the determination can be realized at low cost and is economical. Is.

[0091] shift control device for an automatic transmission according to the fifth invention, as described in claim 5, when the automatic transmission is based on the assumption that it is a continuously variable transmission, directly connected between the input and output elements of the joint , So that the input shaft rotation speed obtained from the signal from the input shaft rotation speed detection means matches the engine rotation speed obtained from the signal from the engine rotation speed detection means,
Since the direct-connection gear change control means controls the speed change of the continuously variable transmission, and the direct-connection timing control means causes the direct connection of the joint to be performed when the direct-connection gear change control is completed, the input shaft rotation speed can be reliably ensured when the direct connection is made. Is matched with the engine speed, and the direct coupling shock of the joint in the continuously variable transmission can be reliably eliminated.

[0092] transmission control system for an automatic transmission according to the sixth invention, as described in claim 6, periodically during the joint is directly connected state, the input shaft rotational speed detecting means with the input shaft rotational speed calculation means The rotation speed of the input shaft is calculated based on the signal of, and the engine rotation speed calculation means calculates the engine rotation speed based on the signal from the engine rotation speed detection means. Since the direct connection failure determination means determines the direct connection failure of the joint from the engine speed mismatch, the direct connection failure of the joint can be surely known, and the shift control of the automatic transmission can be performed without knowing the direct connection failure. It is possible to eliminate the harmful effect of continuing as it is.

[0093] shift control device for an automatic transmission according to the seventh invention, as described in claim 7, when direct failure of the joint in response to the signal from the direct failure determining means, signal selection during direct failure Since the means selects the signal from the input shaft rotation speed detection means to calculate the input shaft rotation speed, the engine speed is not the same as the input shaft speed due to a direct coupling failure of the joint. It is possible to prevent the input shaft rotation speed from being calculated based on the signal from the engine rotation speed detection means and thus prevent the detection result of the input shaft rotation speed from becoming incorrect.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a toroidal-type continuously variable transmission showing an embodiment of a shift control device according to the present invention.

FIG. 2 is a vertical sectional front view showing the toroidal-type continuously variable transmission together with its shift control system.

FIG. 3 is a flowchart showing a shift control program when the controller in the shift control system is configured by a microcomputer.

FIG. 4 is a flowchart showing an interrupt processing of an engine speed signal.

FIG. 5 is a flowchart showing interrupt processing of an input shaft rotation speed signal.

FIG. 6 is a flowchart showing interrupt processing of an output shaft rotation speed signal.

FIG. 7 is a time chart showing changes over time in the engine speed and the input shaft speed when the torque converter is locked up in the stepped automatic transmission.

FIG. 8 is a graph showing the engine speed, the input shaft speed, and the engine speed when a lock-up continuously variable transmission is performed to prevent a lock-up shock when the torque converter is locked up in the continuously variable transmission; It is a time chart which shows the time-dependent change of a wheel rotation speed.

9 is a flowchart showing a shift control program similar to that in FIG. 3, showing another example of the present invention.

FIG. 10 is a shift control system diagram showing still another example of the shift control device according to the present invention.

FIG. 11 is a flowchart showing a shift control program executed by a controller in the same example.

FIG. 12 is a general shift control system diagram of a toroidal type continuously variable transmission.

FIG. 13 is a schematic diagram showing a transmission unit of the toroidal type continuously variable transmission.

FIG. 14 is an explanatory perspective view illustrating a rotation speed detection sensor.

FIG. 15 is a signal waveform diagram showing a pulse signal from the sensor.

16 (a) is a time chart showing a pulse signal output from the same sensor at the time of low rotation, together with a shift control cycle, and FIG. 16 (b) shows a pulse signal output from the same sensor at the time of high rotation, It is a time chart shown with a shift control cycle.

[Explanation of symbols]

1 Input Cone Disc 2 Output Cone Disc 3 Power Roller 4 Step Motor 5 Shift Control Valve 6 Piston 7 Precess Cam 8 Shift Link 20 Input Shaft (Transmission Component) 28 Loading Cam 41 Trunnion 43 Upper Link 45 Lower Link 61 Controller 62 Throttle Open Degree sensor 63 Output rotation sensor (transmission rotation speed detection means) 64 Input rotation sensor (shift control rotation speed detection means: input shaft rotation speed detection means) 65 Engine rotation sensor (shift control rotation speed detection means:
Engine speed detection means) 70 Torque converter (joint) 71 Converter status determination device (joint operating status determination means)

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-2-292562 (JP, A) JP-A-60-129613 (JP, A) JP-A-58-54262 (JP, A) JP-A-3- 288062 (JP, A) JP 3-213756 (JP, A) JP 63-74735 (JP, A) JP 6-81940 (JP, A) JP 5-80063 (JP, A) JP-A-7-43376 (JP, A) Actual development Sho 62-99863 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-63/48

Claims (7)

(57) [Claims] 1. An automatic transmission comprising an input shaft for inputting engine rotation through a slip controllable joint, wherein the number of rotations of the input shaft contributes to gear shift control. An engine rotation speed detecting means for generating a signal, and an input shaft rotation for generating a number of signals according to the rotation speed of the input shaft and generating more signals than the engine rotation speed detecting means under the same rotation speed. Number detecting means, joint operating state determining means for determining whether or not the joint is directly connected between the input and output elements, and a joint for directly connecting the input and output elements in response to a signal from the means. Signal from the engine speed detecting means, and while the joint is not directly connected between the input and output elements, the signal from the input shaft speed detecting means is selected to select the signal from the input shaft. Contributes to calculation of rotation speed Shift control apparatus for an automatic transmission characterized by comprising a signal selecting means. 2. The shift control device for an automatic transmission according to claim 1 , wherein the engine speed detecting means is an engine crank angle sensor. 3. An apparatus according to claim 1 or 2, wherein the joint operating condition determining means, between said joint input element by whether or not the engine is in the operating region to be connected directly between the input and output elements of the joint A shift control device for an automatic transmission, characterized in that it is configured to determine whether or not the gear is directly connected. 4. The method of claim 1 or 2, wherein the joint operating condition determining means determines whether the joint is directly connected between the input and output elements by a signal for controlling the direct between input and output elements of the joint A shift control device for an automatic transmission, characterized in that 5. The automatic transmission according to any one of claims 1 to 4 , wherein when the automatic transmission is a continuously variable transmission, when the input and output elements of the joint are directly connected, A direct-coupling shift control means for controlling the shift of the continuously variable transmission so that the input shaft rotational speed obtained by the signal matches the engine rotational speed found by the signal from the engine rotational speed detecting means, and a direct-coupling gear shifting by the means. A shift control device for an automatic transmission, further comprising direct connection timing control means for directly connecting the joint when control is completed. 6. A any one of claims 1 to 5, periodically during the joint is directly connected state, the rotational speed of the input shaft based on a signal from the input shaft rotational speed detecting means An input shaft rotation speed calculation means for calculating and an engine rotation speed calculation means for calculating an engine rotation speed based on a signal from the engine rotation speed detection means are added, and the input shaft rotation speed and the engine rotation speed calculated by these means are added. A shift control device for an automatic transmission, comprising direct connection failure determination means for determining a direct connection failure of a joint based on the above mismatch. 7. The method of claim 6, wherein in response to a signal from the direct defect determination unit, when direct failure of the joint causes calculates input shaft rotational speed to select a signal from the input shaft rotational speed detecting means A shift control device for an automatic transmission, characterized in that signal selection means for bad connection is added.