JP5013187B2 - Shift lever position sensor - Google Patents

Description

  The present invention relates to a position sensor for a shift lever that detects a position according to a change in detection voltage.

  In a vehicle, a shift control of a transmission that converts a rotational speed, torque, and the like transmitted from an engine by a driver operating a shift lever is performed. In particular, in an automatic transmission (AT), unlike a manual transmission (MT), a position sensor determines the current position of a shift lever, and shift control of the transmission is performed according to the determination result. Has been done. Also, in many AT vehicles, the engine start control, reverse lamp lighting, and the display screen of the display monitor provided in the vehicle are linked to the shooting screen by the back camera in conjunction with the current position of the shift lever. Switching is also being done. Therefore, it is very important for the vehicle that the control unit of each function provided in the vehicle accurately grasps the current position of the shift lever. Therefore, many position sensors capable of accurately grasping the position of the shift lever have been used so far (for example, Patent Document 1).

  In the position sensor according to Patent Document 1, the shift position is recognized using a position sensor having a step-like output characteristic in which the output is constant at each shift position. Therefore, it is possible to accurately recognize the position of each shift position. However, in recent years, a smooth shift with reduced shock at the time of shift is required in vehicles, and in order to perform such a shift, it is necessary to recognize the shift timing earlier. For this reason, in the position information obtained from the shift position sensor, it is necessary to perform a smooth shift by predicting not only the signal after the shift but also the next shift to be performed. In the position sensor according to Patent Document 1, it is necessary to recognize a position to be shifted after shifting from each position to another position, and thus there has been a problem that the shifting operation is delayed.

  In order to improve such a problem, there is a technique capable of predicting the next speed change operation (for example, Patent Document 2). In the position sensor provided in the electronic component mounting apparatus according to Patent Document 2, the sensor output has a linear characteristic, and the detected voltage has a predetermined detection width at each position. It is possible to predict the position to be performed. However, in order to distinguish the current position of the shift position in distinction from adjacent positions, it is necessary to reduce the output variation of the position sensor.

Japanese Patent No. 3814942 (paragraph number 0021, FIG. 7 etc.) Japanese Patent Laying-Open No. 2005-3528 (paragraph number 0024, FIG. 5 etc.)

  In view of the above problems, an object of the present invention is to provide a position sensor for a shift lever that can predict the transition to the next position and that can accurately detect even if the output variation of the position sensor increases. There is.

  In order to achieve the above object, the shift lever position sensor according to the present invention is characterized by detecting the position of the shift lever based on a voltage value output according to the position of the shift lever, and moving the shift lever. And a voltage composed of a plurality of detection regions having a voltage range having a first gradient and a transition region having a voltage range having a second gradient and arranged between the plurality of detection regions. An output unit, and a comparison unit that compares a measured value of the voltage output from the voltage output unit with a predetermined voltage value and detects the current position of the shift lever, and further includes the shift When the lever is operated and moved from one detection region to another detection region among the plurality of detection regions, the change in the measured value of the voltage based on the first gradient in the one detection region is changed. The basis, the other detection area said shift lever in that it comprises a prediction unit for predicting prior to located the other detection area.

  With such a configuration, since the first voltage gradient is present in the detection region, the position to which the measurement target object moves next based on the voltage that changes as the measurement target object moves. Can be easily predicted. In addition, since the voltage gradient in the transition region is steeper than the voltage gradient in the detection region, the output variation can be set large with respect to the threshold values of both, so there is a margin for the output accuracy of the position sensor. it can. Therefore, since the function for increasing the output accuracy can be eliminated, the structure of the position sensor can be simplified.

  In the position sensor of the shift lever, it is preferable that the first gradient is smaller than the second gradient. With such a configuration, the voltage change can be reduced in the detection region as compared to the transition region. Therefore, it is possible to easily detect the position of the shift lever in the detection area and to set a large output variation.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of the position sensor 100 of the shift lever 10 of the present invention. In this embodiment, the position sensor 100 will be described as an example in the case where the position sensor 100 is used for detecting the position of a shift lever of an AT vehicle.

  The position sensor 100 includes a voltage output unit 1, an output voltage detection unit 2, a comparison unit 3, and a prediction unit 4. The voltage output unit 1 sets an output voltage corresponding to the current position of the shift lever 10 in conjunction with the operation of the shift lever 10 performed by the driver, and outputs the output voltage. Here, the transmission 20 in which the position sensor 100 detects the position has a drive system fixed inside the transmission, and is mainly used in the [P] range used when parking, the [R] range used when moving backward, and the transmission inside. Is in a free state and does not transmit power from the engine to the drive system [N] range, [D] range used during normal driving, and when using engine brakes such as downhill, the upper limit of shift up Is used when using a strong engine brake such as a steep downhill, and the gear is fixed at the first speed. The voltage output unit 1 sets and outputs an output voltage corresponding to each of these ranges.

  The output voltage output by the voltage output unit 1 is detected by the output voltage detection unit 2 according to the current position of the shift lever 10. The output voltage detected by the output voltage detection unit 2 is transmitted to the comparison unit 3. The comparison unit 3 compares the output voltage before the shift lever 10 shifts with the output voltage that fluctuates in accordance with the shift lever 10 shift start. The comparison result is transmitted to the prediction unit 4, and based on the result, the direction in which the shift lever 10 changes the range from the current position is predicted (details will be described later).

  When the prediction unit 4 predicts the range shift, the range shift information indicating the range to which the shift lever 10 shifts next is transmitted to the position setting unit 5. The position setting unit 5 performs a shift operation of the transmission 20 based on the range shift information.

  FIG. 2 is a schematic diagram showing the voltage output unit 1. As shown in the upper diagram of FIG. 2, the voltage output unit 1 includes a detection region in which the shift position can be detected for each shift position, and a transition region that passes when shifting from a predetermined detection region to another detection region. It is formed. These detection regions and transition regions are set so that the output voltage differs for each shift position, and are classified into detection voltages in the detection region and transition voltages in the transition region. Further, in the same detection region or the same transition region, the detection voltage or the transition voltage in the region is not constant, and has a first voltage gradient and a second voltage gradient, respectively. The voltage gradient in the detection region is set to be gentler than the voltage gradient in the region. Accordingly, in each detection region and transition region, each region is formed between the lower limit output voltage and the upper limit output voltage.

  As an example of a method of forming the detection region and the transition region so that the voltage gradients are different, there is a method using sliding resistance as shown in the lower diagram of FIG. First, the low resistance material 31 is formed on the substrate 30 by printing or the like. As the low resistance material 31, for example, a material having a sheet resistance of 100Ω / □ is preferably used. Then, a high resistance material 32 is formed thereon. For example, a material having a sheet resistance of 1 kΩ / □ is preferably used as the high resistance material 32.

  The voltage output unit 1 thus formed is grounded so that one end (for example, [P] range side) becomes 0 <V>, and a voltage can be applied to the other end (for example, [1] range side). The power supply 33 is connected as shown in FIG. The voltage applied from the power supply 33 is preferably a stable voltage value so that the shift position detection voltage can be accurately measured. Therefore, instead of directly applying from a battery (not shown), for example, a stable output such as a regulator (so-called dropper) or a DC / DC converter may be applied as the power source 33. However, from the viewpoint of cost reduction, when the output from the battery is used directly as the power source 33, the worst value of the battery is set so as to correspond to the worst value of the detection region or the transition region, or As a matter of course, it is possible to adopt a configuration in which the set voltage in the detection region or the transition region is controlled to vary in accordance with the variation in the output voltage of the battery.

  In this state, the brush 34 that can operate in conjunction with the movement of the shift lever 10 slides on the surface of the voltage output unit 1, and when the output voltage detection unit 2 detects the voltage obtained through the brush 34, In the upper part of the low-resistance material 31, the voltage change is small and has a gentle voltage gradient, and in the upper part of only the high-resistance material 32, the voltage change is large and has a steep voltage gradient. Therefore, an output voltage setting characteristic comprising a detection region having a first gradient in accordance with the shift position as shown in the upper diagram of FIG. 2 and a transition region having a second gradient steeper than the voltage gradient is obtained. Can do.

  FIG. 3 is an enlarged view of the output voltage setting characteristics and the voltage output unit 1 in the [N] range and [D] range in the voltage output unit 1. When the brush 34 is positioned at point a as shown in the lower diagram of FIG. 3, the position sensor 100 detects that the shift lever 10 is moved as shown in the upper diagram of FIG. [N] Recognized as being in range. With the operation of the shift lever 10 by the driver, the brush 34 starts to shift from the point a. For example, when the brush 34 reaches the point b, as shown in the upper diagram of FIG. The output voltage changes. This detection voltage is transmitted to the comparison unit 3, and the detection voltage before shifting to the point b, that is, the detection voltage at the point a and the detection voltage at the point b are compared.

  This comparison result is transmitted to the prediction unit 4, and when the detection voltage during the transition is larger than the detection voltage before the transition as shown in the upper diagram of FIG. 3, the prediction unit 4 moves to the shift range on the higher detection voltage side. Transition is predicted (in this case, transition from the [N] range to the [D] range). On the other hand, when the detection voltage during the transition is smaller than the detection voltage before the transition, the prediction unit 4 predicts that the transition is to the shift range on the lower detection voltage side. As described above, since the shift of the shift range can be predicted based on the fluctuation of the detection voltage in the detection region, smooth shift control can be performed.

Next, output variations of the position sensor 100 will be described. 4A shows output voltage setting characteristics of a position sensor in which the relationship between the output voltage and the shift position used conventionally has a linearity characteristic, and FIG. 4B shows the position sensor 100 according to the present invention. This is an output voltage setting characteristic. 4 (a) and 4 (b) both show the portions from the [N] range to the [D] range. In both cases, the output voltage is set such that the lower limit of the detection area of the [N] range is N _L <V> and the upper limit of the detection area of the [D] range is D _U <V>. The intermediate voltage (D _U −N _L ) / 2 <V> between N _L <V> and D _U <V> is the threshold voltage that is the limit at which the [N] range and the [D] range do not overlap. Yes.

From FIG. 4A, the upper limit of the output voltage setting value of the [N] range is N _U0 <V>, and the upper limit of the output variation in the detection area of the [N] range is the above threshold voltage (D _U Since −N _L ) / 2 <V>, the allowable variation at the upper limit of the detection area of the [N] range is ΔV ₀ which is the difference between these values. Further, the lower limit of the output voltage setting value of the [D] range is D _L0 <V>, and the lower limit of the output variation in the detection area of the [D] range is the threshold voltage (D _U −N _L ) / 2 <V. Therefore, the allowable variation at the lower limit of the detection range of the [D] range is ΔV ₀ which is a difference between these values. When the allowable variation at the upper limit of the detection range of [N] range and the allowable variation at the lower limit of the detection region of [D] range are the same value as ΔV ₀ , the output voltage setting characteristic has a linearity characteristic. Of course it is obvious.

This can be similarly considered at the lower limit of the detection range of the [N] range, and the allowable variation is ΔV _{0 due} to the relationship with the range adjacent to the [N] range, that is, the range with the lower output voltage. . If the output variation is constant in the detection region, the output variation in the [N] range is 2ΔV ₀ . Further, from the same concept, the output variation is 2ΔV ₀ even in the [D] range.

On the other hand, from FIG. 4B, the output variation of the position sensor according to the present invention can be considered as follows. The upper limit of the output voltage setting value of the [N] range is N _U1 <V>, and the upper limit of the output variation in the detection area of the [N] range is the threshold voltage (D _U −N _L ) / 2 <V>. Therefore, the allowable variation at the upper limit of the detection area of the [N] range is ΔV ₁ which is the difference between these values. [D] The lower limit of the output voltage setting value of the range is D _L1 <V>, and the lower limit of the output variation in the detection area of the [D] range is the threshold voltage (D _U −N _L ) / 2 <V>. Therefore, the allowable variation at the lower limit of the detection area of the [D] range is ΔV ₁ which is the difference between these values. Also here, it is clear from FIG. 4B that the allowable variation at the upper limit of the detection region of the [N] range and the allowable variation at the lower limit of the detection region of the [D] range are the same ΔV ₁ .

This can be similarly considered at the lower limit of the detection area of the [N] range, and the allowable variation is ΔV _{1 in} relation to the range adjacent to the [N] range. Therefore, the output variation in the [N] range is 2ΔV ₁ . Furthermore, from the same concept, the output variation is 2ΔV ₁ even in the [D] range.

From the above, when the detection area of the [N] range is arranged, in the linear type of FIG. 4A, from N _L −ΔV ₀ <V> to (D _U −N _L ) / 2 <V>, FIG. In this position sensor 100), N _L −ΔV ₁ <V> is changed to (D _U −N _L ) / 2 <V>. From FIG. 4A and FIG. 4B, the relationship of ΔV ₀ <ΔV ₁ is clear. Therefore, the output variation of the position sensor 100 can be set larger than that of the linear type position sensor.

[Other Embodiments]
In the said embodiment, although the example at the time of utilizing a sliding resistance was shown and demonstrated as the voltage output part 1, it is not restricted to this. For example, the voltage output unit 1 can be formed by changing the resistance value with a winding resistance or the like.

In the said embodiment, although the example at the time of utilizing a sliding resistance was shown and demonstrated as the voltage output part 1, it is not restricted to this. For example, it is possible to determine the first gradient and the second gradient using the output of the trimable Hall IC. If such a Hall IC is used, the correction point for which the output is to be changed as shown in FIG. 5, that is, the upper limit value (for example, P ₀ in the [P] range) and the lower limit value (for example, the [P] range) If P ₁ ) is set, it is naturally possible to obtain the same effect as the present invention. Furthermore, it is naturally possible to use a correction method that can set the gradient of each detection region.

  In the above-described embodiment, the prediction unit 4 has been described as predicting based on the change in the detection voltage in the detection region with respect to the shift range shift, but the present invention is not limited to this. Naturally, it is possible to make a prediction based not only on the detection area but also on the transition voltage change in the transition area.

  In the above embodiment, the detection region and the transition region in the output set voltage characteristics are described as the same voltage range, but the present invention is not limited to this. For example, it is naturally possible to set only a detection range of a specific range such as the [N] range. Such setting can be realized by thinly printing the low-resistance material 31 in the corresponding detection region. Further, it is naturally possible to change and set the voltage gradient of at least a part of the specific detection region and the transition region by making it steep or gentle.

  In the above embodiment, the output set voltage characteristic has been described as a configuration in which the voltage on the [1] range side is higher than the voltage on the [P] range side, but this is not restrictive. Conversely, it is naturally possible to configure the [1] range side to be grounded and the [P] range side to be connected to the power source 33. Furthermore, it is naturally possible to adopt a configuration in which either one is not grounded but a voltage that can generate a potential difference between both ends is applied to each side. Even with such a configuration, it is possible to predict the transition to the next position, and it is possible to obtain the effect that accurate detection is possible even if the output variation of the position sensor increases. it can.

  In the above embodiment, the position sensor 100 has been described as detecting the shift position of the AT vehicle, but the present invention is not limited to this. For example, the position sensor 100 can be used for detecting the position of the seat, and can naturally be used for detecting the position of functions other than the vehicle.

Schematic diagram showing the configuration of the position sensor Diagram showing the outline of the voltage output unit Partial enlarged view of voltage output section Comparison diagram of output voltage setting characteristics of position sensor Diagram showing setting of output voltage by setting correction point

Explanation of symbols

1: Voltage output unit 2: Output voltage detection unit 3: Comparison unit 4: Prediction unit 5: Position setting unit 10: Shift lever 20: Transmission 100: Position sensor

Claims (1)

In the position sensor for detecting the position of the shift lever based on the value of the voltage output according to the position of the shift lever,
A plurality of detection regions that are arranged along a moving direction of the shift lever and have a voltage range having a first gradient, and a transition that is arranged between the plurality of detection regions and has a second gradient. A voltage output unit composed of regions;
A brush that slides on the surface of the voltage output unit in conjunction with the movement of the shift lever;
A comparison unit that compares an actual measurement value of the voltage output from the voltage output unit with a predetermined voltage value, and detects the current position of the shift lever, and
Further, when the shift lever is operated and moved from one detection region to another detection region among the plurality of detection regions, an actual measurement value of a voltage based on a first gradient in the one detection region is obtained. A prediction unit that predicts the other detection area before the shift lever is positioned in the other detection area based on a change ;
The first gradient is set smaller than the second gradient such that a change in output voltage in the detection region is smaller than a change in output voltage in the transition region,
The voltage output unit includes a substrate, a resistance material disposed on the substrate, and a high resistance material disposed on the substrate and having a higher electrical resistance than the resistance material,
In the transition region, the brush slides in a region where only the high resistance material is disposed on the substrate, and a voltage is obtained through the brush.
The detection in a region, said region in which the resistive material is disposed on the substrate brush slides, position sensor of a shift lever, wherein Rukoto voltage obtained through the brush.

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