JP2000337491A - Automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission capable of reducing the ROM capacity of a microcomputer by the simplified control, optimizing the gear shift timing corresponding to a travelling condition, and properly controlling the gear shift while preventing the frequent shift. SOLUTION: In an automatic transmission comprising a driving device capable of automatically changing a gear in a transmission by driving a control mechanism corresponding to a speed of a vehicle detected by a speed detecting means, the difference (Tn-Tn-1) of past period data of wheels is subtracted from a shift fundamental period Tb0, and the gear shift is controlled while using the obtained value as a shift point. As the automatic shift control can be executed by finely and continuously selecting the shift point in accordance with a speed without specially processing the period data as a pulse signal from the speed detecting means, the shift control can be properly, quickly and smoothly executed with a shift timing quickly responding to a travelling condition of a bicycle particularly in reduction, and the ROM capacity of a microcomputer in a control circuit can be reduced by simplifying the gear change control program.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission for a bicycle for automatically shifting a transmission in accordance with a vehicle speed detected by speed detecting means, and more particularly to a bicycle automatic transmission capable of performing a smooth shift adapting to a running state. The present invention relates to drive control in an automatic transmission with a change of a shift point to be performed.

[0002]

2. Description of the Related Art In recent years, various automatic transmissions have been proposed as techniques for automating transmissions that enable bicycles to run lightly. As an automatic transmission of this type in a bicycle, a retracted position of a transmission cable connected to a transmission installed in a rear wheel driving unit or the like is controlled by a driving device such as a motor via a control mechanism according to the speed of the bicycle. The gear is automatically shifted to a predetermined shift position by controlling the traction by a predetermined amount. In such an automatic transmission, control is performed by a drive device such as a motor in accordance with the speed of the bicycle, but the shift is performed so that the automatic shift is performed more appropriately in accordance with the traveling state. Various control devices have been proposed that change the reference value of the speed to be performed, that is, the shift point, according to the running state.

[0003] Examples of these proposals are disclosed in Japanese Patent Laid-Open No. 10-14 / 1998.
No. 7279 (first conventional example), JP-A-10-1816
No. 76 (second conventional example) and Japanese Patent Application Laid-Open No. H11-5955.
No. 4 (third conventional example) is disclosed. The first prior art example is a proposal by the present applicant and the like, but a two-dimensional shift position appropriate map composed of a relationship between speed and acceleration is created in advance, and an area where acceleration or deceleration is small is defined. A dead zone is set between each appropriate shift position to keep the shift position as it was last time, thereby preventing unnecessary shift position changes and enabling a smooth shift with a good operational feeling. is there. Further, the second conventional example estimates a virtual cycle and a virtual speed of a bicycle at the present time from a cycle sequence that is past cycle data of a wheel and a speed function sequence that is speed data by a predetermined deceleration constant,
By performing the shift control based on the virtual cycle and the virtual speed, the optimal shift is performed immediately in real time. Further, in the third conventional example, once a shift is performed, a shift-up mode or a shift-down mode is set, and the shift is performed at a speed different from a normal shift, and the shift timing is shifted, so that the shift after the shift is performed. It is intended to reduce unnecessary shifts and to perform shifts with less discomfort at fast shift timing.

[0004]

However, in each of the above-mentioned automatic transmissions, in the first prior art,
Since a two-dimensional shift position appropriateness map composed of the relationship between the speed and the acceleration is created in advance, a large memory is required, and complicated calculation in acceleration control and the like is inevitable. In the second conventional example, the deceleration constant needs to be set in advance in a ROM or the like in the control circuit, which requires a capacity.
Although the calculation process of the virtual speed is complicated and the optimal shift is performed immediately in real time, the shift is uniform because the preset deceleration constant does not correspond to the change in speed. It could not be said that it corresponded to real driving conditions. Further, in the third conventional example, although effective in preventing frequent shifts, the shift control tends to be monotonous and the control is complicated.

The present invention solves the above-mentioned problems of the conventional automatic transmission by reducing the ROM capacity of the microcomputer by simplified control, and further optimizing the shift timing in accordance with the running state, thereby reducing the frequency. SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic transmission that can perform appropriate shift control while preventing a shift from occurring.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention relates to an automatic transmission having a drive device for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detection means. Is subtracted from the shift basic cycle, and the shift control is performed using the difference as a shift point. According to another aspect of the present invention, there is provided an automatic transmission having a driving device for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by a speed detecting means, wherein a difference between past cycle data of wheels is provided. When a value is exceeded, a shift point is changed to perform shift control. According to another aspect of the present invention, there is provided an automatic transmission having a driving device for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detecting means. The present invention is characterized in that a shift is controlled by subtracting the shift from a basic speed and setting the shift as a shift point. According to another aspect of the present invention, there is provided an automatic transmission having a drive unit for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detection means, wherein a difference between past speed data on wheels is provided. When a value is exceeded, a shift point is changed to perform shift control. Further, the present invention is characterized in that upshifting within a predetermined time after shifting down is prohibited. Further, the present invention is characterized in that, after a downshift, the upshift is prohibited while the speed signal does not reach a predetermined count number, and these are used as means for solving the problem. is there.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show a first embodiment of an automatic transmission according to the present invention. FIG. 1A is an overall side view of a bicycle provided with the automatic transmission according to the present invention, and FIG.
2 is a side view of the rear wheel on which the speed detection unit is installed, FIG. 2 is an internal plan view of the upper case of the actuator box, FIG. 3 is an internal bottom view of the lower case of the actuator box, and FIG. FIG. 5 is a block diagram of the automatic transmission, FIG. 6 is a flowchart of a shift point change control in the automatic transmission of the present invention, and FIG. 7 is a diagram showing a control processing time table. As shown in FIG. 1, in a bicycle provided with the automatic transmission according to the present invention, a transmission 15 such as a built-in type is installed in a rear wheel drive hub and housed in an actuator box 3 installed near a hanger. The pull-in position of the transmission cable 13 with respect to the transmission 15 by the control mechanism is controlled by a predetermined amount in accordance with the speed of the bicycle to automatically shift to a predetermined transmission position.

The actuator box 3 includes an upper case 1
And a lower case 2. The lower case 2 is attached to a hanger portion of the vehicle body by a mounting bracket fixed to an upper portion of the upper case 1. A battery box 11 is provided adjacent to and above the actuator box 3 for storing a power source of a drive unit in a control mechanism of a transmission in an automatic transmission and a battery serving as a power source of a control circuit in a control unit. Is done. Reference numeral 58 denotes an initial reset switch which is disposed on the side surface of the battery box 11 so as to be exposed to the outside. When the initial reset switch is depressed, it informs the control unit of the automatic transmission of error information and adjusts a reference position for pulling the transmission cable. Motor drive and the like can be performed.

In the automatic shifting of the transmission, upshifting or downshifting is automatically performed by a control mechanism according to the vehicle speed detected by the speed detecting means. A reed switch 17 installed on a frame such as a stay is arranged close to the rotational trajectory of a magnet 14 installed on a rear wheel spoke or the like, and the number of pulses per unit time generated by the contact and separation of these two is counted. A device for detecting the rotational speed of the rear wheels, that is, the vehicle speed (and acceleration) of the bicycle, or the like is employed, and the speed detection signal is used as a shift control signal of the automatic transmission. As shown in FIG. 3, the start end of the transmission cable 13 whose rear end is connected to the transmission 15 is engaged with the outer peripheral surface of the transmission pulley 8 supported in the lower case 2 of the actuator box 3. Fixed. The speed change cable 13 is inserted through a spacer 18 into the outer whose adjustable position is adjusted by the adjuster 16 with respect to the hexagon nut 20 locked to the introduction portion of the lower case 2 so as to be able to be pulled. Reference numeral 33 denotes a retaining ring of the speed change pulley 8, 19 denotes a square nut, 21 denotes a screw connecting the upper and lower cases, and 32 denotes a ventilation sheet.

As shown in FIG. 2, in an upper case 1 of the actuator box 3, a cam gear 4 integrally connected to a transmission pulley 8 to which a starting end of the transmission cable 13 is locked and fixed coaxially 9 is provided. Is supported. A large number of teeth are engraved on the outer periphery of the cam gear 4, and a small gear in the second reduction gear 5 that rotates by receiving a driving force from a driving device such as a motor 26 is formed on these teeth. Are engaged. The small gear of the first reduction gear 6 meshes with the outer periphery of the large gear of the second reduction gear 5. The worm 7 fixed to the output shaft of the motor 26 meshes with the outer periphery of the large gear of the first reduction gear 6. A concave portion (FIG. 4) is formed at a portion corresponding to each shift position in a portion where the teeth of the cam gear 4 are not cut.
The detector in the microswitch 27, which is the detecting means, falls into these concave portions corresponding to the towing amount of No. 3 to detect the shift position. As the detection means, a photocoupler, a potentiometer, or the like can be employed in addition to the microswitch. Reference numeral 30 denotes a board on which a control circuit and the like are provided.
A control unit for controlling the driving of the motor 26 is formed. Reference numeral 10 denotes shafts of the reduction gears 5 and 6, 12 denotes a seal grommet, 22 denotes a board mounting screw, 23 denotes a mounting bracket mounting screw, and 24 denotes a micro switch 27 mounting screw.

The automatic transmission constructed as above operates as follows. When the vehicle starts running, it receives a pulse signal from a speed detecting unit composed of a magnet 14 installed on a rear wheel spoke or the like and a reed switch 17 installed on the stationary side, and the speed signal is distributed on a substrate 30. The cam gear 4 which has been subjected to arithmetic processing in the provided control circuit and has been reduced through the worm 7, the first and second reduction gears 6, 5 by the forward rotation of the motor 26, has the first gear through the first gear as shown by arrows in FIG.
Rotate the shift position up to the third speed. Along with this, the transmission pulley 8 (FIG. 3) integral with the cam gear 4 pulls the rear end of the transmission cable 13 to automatically shift the internal transmission 15 installed in the rear wheel hub. I do.

FIG. 5 is a block diagram of the automatic transmission according to the present invention. When the wheels start to rotate when the vehicle starts running, pulses generated by a speed detector 52 constituted by the magnet 14 and the reed switch 17 are generated. Is transmitted to the main control circuit unit 54 to change from the stop mode, which is the energy saving mode, to the running mode. The main control circuit 54 receives the speed detection signal SP and
A low-battery detection circuit that detects a shift position signal PS obtained from a shift position detecting unit 57 based on a signal from the micro switch 27 in FIG. 2 and a reduction in a power supply voltage of a driving device in a control mechanism of the transmission below a predetermined value. Each input of the low battery detection signal LS from 53 is taken in, processed and processed, and a processing signal CS for automatic shifting is sent to the motor drive circuit section 55. The motor 26 is rotationally driven by a drive signal from the motor drive circuit 55, and automatic shift control is performed. Reference numeral 56 denotes an LED output unit for displaying a shift position, detection of a low battery, and the like. Reference numeral 59 denotes a wheel diameter setting unit which appropriately corrects the pulse-speed conversion value in accordance with the standard of the wheel size where the magnet 14 and the reed switch 17 are installed to constitute the speed detection unit 52.

A motor drive method determining unit is provided in the main control circuit unit 54. Based on the determination result, the magnitude of the drive power of the drive unit is controlled according to the load in the drive direction. For example, in the case where the drive device is configured to shift up the transmission by rotating the control mechanism in the normal direction against a predetermined biasing force, the shift-up is performed by normal control of full power by the forward drive of the drive device. The reverse driving in the downshift direction is performed by low output control, for example, pulse width modulation (PWM) control. The most characteristic feature of the present invention is that in a bicycle automatic transmission including a driving device that drives a control mechanism in accordance with a vehicle speed detected by a speed detection means to automatically shift a transmission, the acceleration data and the like are provided. The shift control is performed by changing the shift point based on the difference between the past cycle data or the difference between the speed data of the wheels without relying on a complicated calculation method.

The shift control of the automatic transmission according to the first embodiment of the present invention will be described below with reference to FIGS. 6 and 7. In FIG. 6, when the wheels start to rotate by the start of running of the vehicle, a running mode is set. In step S1, the initial setting of the control circuit of the automatic transmission is performed. When the running is continued, the shift position and speed data are set in step S2. The speed detection signal SP which is a pulse generated by the speed detection unit 52
(See FIG. 7 etc.). Next, when error processing is performed in step S3 and it is confirmed that there is no error, in step S4, the interval between the speed detection signals SP, that is, cycle data is compared. Period Tn> T
If n- ₁ , that is, if the cycle is longer than the previous cycle, it is determined that the vehicle is decelerating, and the process proceeds to step S7, where the cycle Tn>
If it is not Tn- ₁ , it is determined that the vehicle is moving at a constant speed or accelerating, and the process shifts to step S5 to calculate the shift position to the upshift side according to the traveling speed, and the upshift operation is performed in step S6.

If it is determined in step S4 that the vehicle is decelerating in the cycle Tn> Tn- ₁ , the process proceeds to step S7. In step S7, the difference between the current cycle Tn of the wheel, the past cycle data, and the shift basic cycle. The magnitude of the difference from is compared. Assuming that the mutual relationship between the current input cycle Tn and the past input cycle Tn ₋₁ is ΔT, it is expressed by the following equation. ΔT = α (Tn−Tn ₋₁ ) (1) Here, it is assumed that α = 1. This is a simple current and past pulse period difference. The present embodiment is configured so that the shift points can be continuously switched. Referring to the control time table of FIG.
-Between T1, between T1 and T2, between T2 and T3, T3 and T4
In this case, the period between T4 and T5, that is, the period that is the interval between the speed detection signals SP increases, and the shift point Tb is represented by the following continuous function. Tb = Tb0−ΔT (period difference) = Tb0− (Tn−Tn− ₁ ) (2)

Here, Tb0 represents a shift basic cycle (shift point when the cycle difference is 0). That is, when the cycle increases as the vehicle decelerates, the shift point Tb
Changes as shown in the figure according to the value of Tb0- (Tn-Tn- ₁ ). This means that the period difference (Tn-Tn _-1 ) increases depending on the degree of deceleration, so that Tb decreases and the shift point is controlled at a high speed (for example, the shift is controlled at a speed of 12 Km / h per hour). Is controlled at a shift point of 15 km / h.)
It means to move to. As described above, in the present embodiment, the shift points are configured to be continuously switched. When the speed is high, the cycle becomes small, so even if the speed changes at that time, the cycle difference is relatively small. Therefore, the shift point does not greatly change, and a smooth shift operation suitable for the running state can be performed.

At time T4 in FIG.
When the _value becomes larger than b0- (Tn-Tn- ₁ ), the process shifts from step S7 to step S8 in FIG. 6 to calculate the DOWN-side shift position, which is obtained by Tb0- (Tn-Tn- ₁ ). At the changed shift point, a downshift (third speed to second speed in the illustrated example) is performed (step S6). At this time, since the shift point has shifted to a higher speed as the vehicle decelerates, if acceleration is performed shortly after time T4, there will be a short interval between the shift point and the shift-up. Upshifting is performed immediately after downshifting, and frequent shift control causes a sense of incongruity. Therefore, in the present invention, in step S9, after downshifting, for a predetermined time Th (between times T4 and T6 in FIG. 7). Is configured to prohibit upshifting.
In the present invention, the shift-up after the shift-down is prohibited, and the shift-up during the speed signal does not reach the predetermined count after the shift-down is prohibited instead of during the predetermined time Th. It may be configured as follows. In step S7, Tn is Tb0- (Tn-Tn- ₁ ).
While it is smaller (before time T4), the shift point Tb
Decreases momentarily (shifts to a higher speed), but no downshift is performed.

FIGS. 8 and 9 show a second embodiment of the automatic transmission according to the present invention. While the shift point of the first embodiment is configured to be continuously switched, the embodiment of the present embodiment is configured so that the shift point is gradually switched. is there. Time T0-T1, T1-T2, T
The period between 2 and T3, between T3 and T4, and between T4 and T5, that is, the period that is the interval between the speed detection signals SP increases (deceleration).
Then, the period difference ΔT (= Tn−Tn ₋₁ ) increases. Referring to the control time table of FIG. 9, if it is determined in step S4 of FIG. 8 that the vehicle is decelerating in the cycle Tn> Tn- ₁ , the process proceeds to step S7. (Tn-T
n _-1 ) and a predetermined value (threshold) ΔTb0 are compared. If the cycle Tn is not greater than Tn- ₁ , it is determined that the vehicle is moving at a constant speed or accelerating, and the process shifts to step S5 to calculate a shift position to the upshift side according to the traveling speed, and an upshift operation is performed in step S6. .

If it is determined in step S7 that the difference (Tn-Tn _-1 ) between the past cycle data of the wheels is larger than a predetermined value (threshold) ΔTb0, as shown in FIG. At T4), the shift point is switched from Tb0 to Tb1. Then, the current cycle Tn is Tb
If it is larger than 1 (step S8), step S1
At 0, the DOWN-side shift position is calculated, and at the shift point Tb1, the downshift is performed (3rd to 2nd speed in the illustrated example).
Is performed (step S6). When the speed is high, the cycle becomes small. Even if the speed changes at that time, the cycle difference is relatively small, so that the shift point does not change. Also in the present embodiment, in order to prevent a sense of incongruity due to frequent shift control, in step S11, after a downshift, a predetermined time Th (time T4 to T4 in FIG.
6) is configured to prohibit upshifting. In step S7, the difference of the period data (Tn-Tn- ₁ )
When it is determined that the predetermined value (threshold) ΔTb0 has not been reached, the process proceeds to step S9, and if the current cycle Tn is larger than the shift point Tb0, the process proceeds to step S10 to shift down. If the current cycle Tn becomes smaller than the shift-up shift point in step S5 due to subsequent traveling (acceleration or the like is performed), a shift operation such as shift-up is performed, although not shown in FIG. This is performed (step S6).

FIG. 10 shows a third embodiment of the present invention.
Therefore, in the present embodiment, the speed is detected by the speed detecting device.
The period that is the pulse interval is simply inversely proportional to the speed.
Focusing on the difference in past speed data on wheels,
Subtract from basic speed (shift point when speed difference is 0)
And the shift control is performed using this as the shift point.
It was done. FIG. 6 is a control flowchart.
V in place of T in, with the inequality sign reversed
Therefore, the illustration is omitted. Time T0
From T4 to T4, the speed difference ΔV (negative sign) (=
Vn-Vn _-1) Increases or decreases according to the rate of decrease in speed
Migrate. Therefore, the shift point Vb also increases or decreases.
Transition. The difference between the past speed data (Vn-Vn_-1Change)
Vb = (Vb0−
(Vn-Vn_-1)) = Vb0 + (Vn_-1-Vn) now
Vb is larger than the speed Vn compared to the speed Vn
At the time point (time T4), the vehicle shifts by the shift point Vb.
Downshifting (3rd to 2nd speed in the illustrated example) is performed. Real truth
Also in the embodiment, a predetermined time Th after the downshift or
Shift up until the specified number of pulses are counted
Is forbidden.

FIG. 11 shows a fourth embodiment of the present invention. In this embodiment, the shift point is changed when the difference between the past speed data of the wheels exceeds a predetermined value (threshold). Thus, the speed change control is performed. That is, while the shift point of the third embodiment is configured to be continuously changed,
In the present embodiment, the shift point is configured to be switched stepwise. Also in the present embodiment, as the control flowchart, V in place of T in FIG. 8 may be used, and the inequality sign may be reversed.
The illustration shown is omitted. After the start of traveling, when the vehicle decelerates to time T4, the speed difference ΔV (negative sign) (= Vn−V
n _-1 ) shifts while increasing or decreasing according to the rate of decrease in speed. The speed difference ΔV is compared with a predetermined value (threshold value) ΔVb0, and until time T4, the speed difference ΔV is equal to the threshold value ΔVb0.
Since it is smaller than 0, the shift point is set to Vb0, and at time T4, the speed difference ΔV (− (Vn−Vn ₋₁ ) = Vn ₋₁ ).
The shift point is changed to Vb1 when −Vn becomes larger than the threshold value ΔVb0, and if the current speed Vn is smaller than Vb1, a downshift (third speed to second speed in the illustrated example) is performed at the shift point Vb1. Done. Also in the present embodiment, upshifting is prohibited for a predetermined time Th after a downshift or until a predetermined number of pulses are counted.

The embodiments of the present invention have been described above. However, within the scope of the present invention, the type of transmission and its installation position, the type of speed detecting means and its installation position, and the control mechanism of the transmission The type of actuator that constitutes and its installation position, the type of motor that is the driving device,
The control form and the like of each control unit can be appropriately selected.

[0023]

As described above, according to the present invention, there is provided an automatic transmission having a drive device for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detecting means. By subtracting the difference between the past cycle data of the wheels from the basic shift cycle and performing shift control using the difference as a shift point, the cycle data which is a pulse signal from the speed detecting means can be specially processed. The automatic shift control can be performed by selecting a shift point precisely and continuously according to the speed, so that it is appropriate, prompt and smooth, especially at the time of deceleration, under the shift timing that is appropriate to the running state of the bicycle. , And the ROM capacity of the microcomputer in the control circuit can be reduced by simplifying the shift control program. Further, when the shift point is changed and the shift control is performed when the difference between the past cycle data of the wheels exceeds a certain predetermined value, the shift point is not changed while the cycle difference is small, Unnecessary shifting can be eliminated. Further, in a case where the difference between the past speed data of the wheels is subtracted from the shift basic speed and the shift control is performed using the difference as a shift point, the speed detecting means is simply determined by using speed data that is simply inversely proportional to the cycle. Using the pulse data from the cycle data, i.e., speed data, without special processing, the speed change point is selected continuously and finely continuously according to the speed, and the automatic speed change control is performed. The shift control can be performed appropriately, promptly and smoothly based on the shift timing in response, and the ROM capacity of the microcomputer in the control circuit can be reduced by simplifying the shift control program.

Further, when the shift point is changed and the shift control is performed when the difference between the past speed data of the wheels exceeds a certain predetermined value, the shift point is changed while the cycle difference, that is, the speed difference is small. , And unnecessary shifts can be eliminated. Also, when the shift-down is configured to prohibit the shift-up within a predetermined time, or after the shift-down, when the shift-down is configured to prohibit the shift-up while the speed signal does not reach the predetermined count number. Since upshifting is prohibited immediately after downshifting due to change of the shift point, it is possible to prevent a sense of incongruity due to frequent shift control. As described above, according to the present invention, the ROM capacity of the microcomputer can be reduced by the simplified control, and the shift timing is further optimized according to the traveling state, so that frequent shifts can be prevented. An automatic transmission is provided which enables a precise shift control.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of an automatic transmission according to the present invention. FIG. 1 (A) is an overall side view of a bicycle provided with the automatic transmission according to the present invention, and FIG. It is a side view of the rear wheel in which the detection part was installed.

FIG. 2 is an internal plan view of the upper case of the actuator box.

FIG. 3 is an internal bottom view of the lower case of the actuator box.

FIG. 4 is an explanatory diagram of a shift position by a cam gear.

FIG. 5 is a block diagram of the automatic transmission.

FIG. 6 is a shift point change control flowchart in the automatic transmission according to the present invention.

FIG. 7 is a diagram showing a control processing time table of the same.

FIG. 8 is a shift point change control flowchart showing a second embodiment of the automatic transmission according to the present invention.

FIG. 9 is a diagram showing a control processing time table of the same.

FIG. 10 is a diagram showing a control processing time table showing a third embodiment of the automatic transmission according to the present invention.

FIG. 11 is a diagram showing a control processing timetable showing a fourth embodiment of the automatic transmission according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 upper case 2 lower case 3 actuator box 4 cam gear 5 second reduction gear 6 first reduction gear 7 worm 8 transmission pulley 11 battery box 13 transmission cable 14 magnet 15 transmission 17 reed switch 26 motor 27 micro switch 30 board (control circuit ) 58 Initial reset switch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenichi Ii 3-1-1 Nakatsuma, Ageo City, Saitama Prefecture Inside Bridgestone Cycle Co., Ltd. (72) Inventor Nobuaki Shimada 3-1-1 Nakatsuma, Ageo City, Saitama Prefecture F-term in Bridgestone Cycle Co., Ltd. (reference) 3J052 AA04 BB02 BB16 CA01 FB31 GC46 LA01

Claims (6)

[Claims] 1. An automatic transmission having a drive unit for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by a speed detection means, wherein a difference between past cycle data on wheels is changed. An automatic transmission, wherein a shift is subtracted from a basic cycle and the shift is controlled as a shift point. 2. An automatic transmission having a drive unit for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detection means, wherein a difference between past cycle data on wheels is predetermined. An automatic transmission, wherein a shift point is changed to perform a shift control when a value is exceeded. 3. An automatic transmission having a drive unit for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by a speed detection means, wherein a difference between past speed data on wheels is determined. An automatic transmission, wherein a shift is subtracted from a basic speed and the shift is controlled using the shift as a shift point. 4. An automatic transmission having a drive unit for automatically shifting a transmission by driving a control mechanism in accordance with a vehicle speed detected by speed detection means, wherein a difference between past speed data on wheels is predetermined. An automatic transmission, wherein a shift point is changed to perform a shift control when a value is exceeded. 5. The automatic transmission according to claim 1, wherein an upshift within a predetermined time after a downshift is prohibited. 6. The automatic transmission according to claim 1, wherein after shifting down, shifting up is prohibited while the speed signal does not reach a predetermined count number.