JPS61253230A - Electronically controlled speed change gear for automobile - Google Patents

Abstract

PURPOSE:To make it possible to start an automobile in a speed change range in accordance with the load of an engine irrespective of accelerating work, by detecting an actual loading weight and a gradient, and by providing a traveling load computing means for computing the traveling load in accordance with the detected data. CONSTITUTION:In a stopping condition in which a speed V detected by a vehicle speed sensor 7 is zero, either of first and second speed change ranges is automatically selected during starting of a vehicle in accordance with a detected loading weight W by a loading weight detecting sensor 13 and a detected ascending gradient theta by a gradient sensor 14. Further, controller 6 controls a change-over valve 4 such that the shift position of the speed change gear is held in the selected speed change range irrespective of the detected vehicle speed by the vehicle speed sensor 7 and a detected accelerator opening degree F by a potentiometer 10 if a speed change lever 11 is set at each of stationary speed change range positions 1 through 4 or a backward range position R.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an electronic control system for an automobile that is equipped with means for automatically selecting a predetermined shift range according to the driving load by electronic control when starting the automobile. Regarding transmission.

(Prior Art) This type of electronically controlled transmission for automobiles described above is capable of reliably starting without stalling even under high load, such as when the loaded weight is large, while at the same time, it is possible to From the viewpoint of acceleration performance and fuel efficiency, it has been considered to provide means for automatically selecting a shift range at the time of starting, in accordance with the running load, so that the vehicle starts in the 2nd speed range, for example. For example, the driving load is detected based on accelerator work such as changes in accelerator pedal depression speed, and if the accelerator opening is low, the vehicle will start in the 2nd gear range, and if the accelerator opening is high, it will start in the 1st gear range. It has been considered to provide a means for automatically selecting a shift range at the time of starting according to the running load (for example, see Japanese Patent Publication No. 13928/1983).

In addition, the running load, such as the load and gradient, is detected from the ratio of the throttle opening and the vehicle speed, and when the running load is large, the shift point is raised, and when the load is high, the shift point is set to a relatively low shift range. A method of controlling the vehicle so that the vehicle travels at the same speed as the vehicle is also considered (see Japanese Patent Laid-Open No. 59-126141).

(Problems to be Solved by the Invention) However, the conventional configuration described above has the following disadvantages, and there is room for improvement.

In other words, the former configuration detects the running load based on the accelerator work and controls the vehicle to start in the 2nd gear range when the accelerator opening is low, but does not detect the actual load or slope; Since the configuration indirectly detects the running load based on accelerator work such as changes in accelerator pedal depression speed, for example, even when the load or slope is large, if you try to start slowly,
If the vehicle starts with a low accelerator opening, it will be determined that the running load is low and the vehicle will start in the second gear range.

In addition, in the latter case, where the running load is detected from the ratio of the vehicle speed and the throttle opening to control the shift point, since the vehicle speed is zero at the time of starting, the ratio between the vehicle speed and the throttle opening is cannot be asked for. Therefore, there is a disadvantage that it is not possible to determine the running load at the time of starting.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to enable efficient and reliable starting of a vehicle regardless of the running load.

(Means for Solving the Problems) Features of the electronically controlled transmission for a vehicle according to the present invention include: a load amount detection means for detecting the load amount of the vehicle; a slope detection means for detecting the slope of the ground by the inclination of the vehicle body; a stop detecting means for detecting that the stop detecting means is in a stopped state, and a running load is determined based on the load amount detected by the load amount detecting means and the gradient detected by the slope detecting means in a state where the stop detecting means detects the stopped state. The driving load calculation means calculates the driving load, and the control means automatically selects the shift range of the transmission at the time of starting based on the driving load calculated by the driving load calculation means. The effects are as follows.

(Function) That is, when the vehicle is stopped, the actual load and slope are detected, and the running load is calculated from the detected information, for example,
If the running load is large, the vehicle will start in the 1st gear range,
When the running load is small, the shift range at the time of starting is automatically selected in accordance with the actual running load, such as starting in the 2nd gear shift range, which is the high speed shift range.

(Effects of the Invention) Therefore, since the actual running load is detected, the vehicle can be started in a shift range corresponding to the load regardless of the accelerator work, and the vehicle can be started reliably. Moreover, when the vehicle is stopped, it is not affected by vehicle vibration or acceleration when starting, so it is necessary to provide a means to eliminate the effects of vehicle vibration and acceleration in the means for detecting the running load. Since there is no detection means, the detection means and detection signal processing can be simplified, and the degree of freedom in selecting and mounting the detection means can be increased, making it highly versatile.

Therefore, it is effective to apply the present invention to automobiles with large loading capacity changes, such as trunks and buses.

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

Figure 1 is a control block diagram of an electronically controlled automobile transmission that automatically switches gear ranges using electronic control. Drive wheels (3) via a transmission (2) with a variable speed clutch mechanism (1) with selectable positions
It is configured to communicate.

The clutch mechanism (1) is operated by pressure oil from a hydraulic pump (5) sent through a switching valve (4), and is controlled by a control signal from a controller (6). The switching position of the switching valve (4) is controlled to transmit the output of the engine (E) to the driving wheels (3) at a predetermined reduction ratio.

The controller (6) basically controls the transmission (2).
), a vehicle speed sensor (7) configured to detect vehicle speed (V) by measuring the rotational speed of the output shaft of the accelerator (
8), an accelerator switch (9) that detects whether the accelerator (8) is operated, an accelerator opening degree (F) detected by a potentiometer (10) whose output voltage changes in conjunction with the depression of the accelerator (8), and a shift range position. The switching position of the switching valve (4) is controlled based on each signal from a shift select switch (12) that detects the operating position of a shift lever (11) for selecting a shift. It is.

Furthermore, a load sensor (13) is provided as a means for detecting the amount of cargo loaded, and a gradient sensor (4) is provided as a means for detecting the gradient of the running road surface by detecting the longitudinal inclination of the vehicle body. In a stationary state where the vehicle speed (v) detected by the vehicle speed sensor (7) is zero, the load amount (-) detected by the load amount detection sensor (13) and the pitching slope (θ) detected by the slope sensor (14) are ), it is configured to automatically select which of the first and second speed ranges to use as the shift range when starting the vehicle.

To explain the load amount sensor (13) in detail, as shown in FIG. 4, the spring material (15) for suspending the axle of the platform side wheel, that is, the drive wheel (3), due to a change in the load amount (匈).
and the vehicle body by a link member (16) having one end pivoted to the vehicle body side and the other end pivoted to the spring member (15).
), and the rotation change is detected by a potentiometer, an encoder, etc. However, any device that can detect the load amount (-) when the vehicle is stopped can be used. It may be a composition.

Similarly, the gradient sensor (14) may be any means as long as it can detect the vehicle body inclination, that is, the climbing gradient (θ). A potentiometer, an encoder, or the like may be used to detect the rotation of the supporting weight around the axis of the weight, which rotates as the vehicle body tilts.

As shown in FIG. 2, the shift range positions selected by the shift lever (11) for shift operation include the parking position (P) used when parking the vehicle, the fixed shift range positions of 1st to 4th speeds ( ■～■), an automatic shift range position (D) where the gears are automatically shifted over the entire shift range, a reverse range position (R), and an intermediate position between the automatic shift range position (D) and the reverse range position (R). The parking position (P) is located below the lowest speed position, and the shift range positions are arranged sequentially from the low speed side to the high speed side. The respective shift range positions are arranged in an H shape so that the automatic shift range position (D) is located at the upper position. Shift operations are then performed in accordance with this H-shaped pattern of shift range positions.

As shown in the flowchart of FIG. 3, the controller (6) moves the gear shift operation shift lever (11) to each of the fixed gear ranges W(1 to 4) while driving.
■~■) and reverse range position (R), the vehicle speed (V) detected by the vehicle speed sensor (7) and the accelerator opening degree (F) detected by the potentiometer (10)
), the switching position of the switching valve (4) is controlled so that the shifting position of the transmission (2) is fixed at the selected shifting range position.

On the other hand, when the shift lever (11) is operated to the automatic shift position (D), the vehicle speed sensor (7
) and the accelerator opening (F) detected by the potentiometer (lO), the shift range position of the transmission (2) is determined to be optimal for the running load according to the shift map shown in Fig. 5. The switching position of the switching pulp (4) is controlled so that the switching pulp (4) is in the same position as the switching pulp (4).

In this automatic shift range position (D), when the vehicle speed (V) detected by the vehicle speed sensor (7) as a stop detection means is zero, that is, when the vehicle is stopped, the load amount detection sensor (13 ) The running load is calculated from the detected load (-) by the slope detection sensor (14) and the slope (θ) detected by the slope detection sensor (14), and based on the magnitude of the load, the shift range at the time of starting is set to 1st or 2nd speed. It automatically selects whether to

The automatic selection means for the shift range at the time of starting will be explained below.

That is, at the time of starting, the acceleration (α) of the vehicle body, which changes depending on the running load, can be determined by the following formula.

gXIeXi”+r”XW Note that each variable is defined as shown below.

α: Vehicle acceleration (m/5) Te: Engine output torque (kg = m) i: P
, G, RxT, M, G, R (reduction ratio) μr: Rolling resistance coefficient r: Wheel radius (tire radius) (n) W: Loading capacity (kg) θ: Uphill slope (deg) g: Gravitational acceleration (m) /s”) ■e: Moment of inertia of the rotating part of the engine (kg--・
sz) Then, by substituting the reduction ratios (il) and (it) of each shift range of 1st speed and 2nd speed into the above equation, the respective accelerations (α
υ, (αt) are determined, the magnitude of this acceleration (αI) + (α2) is compared, and control is performed so that the vehicle starts using the shift range that has the greater acceleration determined for one of the two. In other words, by comparing the acceleration force in each shift range of the 1st gear range and the 2nd gear range higher than this 1st gear range using the running load as a parameter, the state of the running load at the time of starting can be indirectly determined. be. In addition, especially in vehicles used for transporting luggage such as trunks, the speed reduction ratio setting state of the transmission means that when there is no load, the acceleration in the 2nd gear range is greater than in the 1st gear range. It has characteristics. By the way, in this embodiment, the magnitude of the running load is determined by comparing the magnitude of the acceleration of the vehicle body in each of the speed change ranges and the second speed range, but the detected load t (W) and The running load may be determined directly from the detected gradient (θ).

In other words, since the actual running load is detected when the vehicle is stopped, it is possible to reliably start the vehicle in a shift range that corresponds to the actual running load at the time of starting, regardless of the accelerator work.

In addition, similar to manual shift type transmissions, any shift range position within the shift range provided by the transmission can be selected as a fixed shift range using the shift lever for shift operation, and the shift lever can also be used to switch to automatic shift. It can also be operated using the same shift lever for changing gears, greatly improving operability. Furthermore, since the fixed shift range positions for manual operation are provided over the entire shift range for automatic shift, the vehicle can be driven with low fuel consumption. For example, if the transmission according to the present invention is used in a vehicle for transporting cargo such as a truck, it will automatically shift gears when the vehicle is loaded with cargo, and switch to a fixed shift range for manual operation while driving. This has the effect of reliably preventing engine stalling and enabling stable driving with good fuel efficiency. Conversely, when driving with luggage loaded, the speed is reduced to 9〒 by manual shifting.
However, by automatically shifting the gears when the load is relatively light, such as when the vehicle is not loaded, it is possible to drive the EasyTribe without the hassle of shifting gears without significantly reducing fuel consumption.

In addition, since the shift range position can be fixed over the entire shift range, acceleration and deceleration operations can be performed by simply operating the accelerator in any shift range during steady driving, and the acceleration response to accelerator operation is good. Can be used. Similarly, engine braking can be applied at any shift range position while the shift range position is fixed to the driver's preference.

[Brief explanation of drawings]

The drawings show an embodiment of the electronically controlled transmission for an automobile according to the present invention, in which FIG. 1 is a block diagram of the control system, FIG. 2 is a diagram showing the arrangement of shift ranges of the shift lever, and FIG.
FIG. 4 is a flowchart showing the operation of the controller, FIG. 4 is an explanatory diagram of the configuration of the load detecting means, and FIG. 5 is a shift map for determining the shift range during automatic shift. (V)...Vehicle speed, (F)...Accelerator opening, (W)...Loading capacity, (θ)...
Gradient, (α)... Running load, (2)...
・Transmission, (7)... Stop detection means, (13)
... Loading amount detection means, (14) ... Gradient detection means.

Claims (1)

[Claims] (1) An electronically controlled transmission for an automobile, which is equipped with a means for automatically selecting a predetermined shift range according to the running load by electronic control when the automobile starts, and detects the loading amount of the automobile. detection means; gradient detection means for detecting the slope of the ground by the inclination of the vehicle body; stop detection means for detecting that the vehicle is in a stopped state; and said loading amount detection means in a state in which said stop detection means detects a stopped state. A running load calculating means for calculating a running load based on a detected load amount by the sensor and a slope detected by the slope detecting means, and automatically changing the gear range of the transmission at the time of starting based on the running load calculated by the running load calculating means. An electronically controlled transmission for an automobile, which is equipped with a control means selected from the following.