JP2018122857A - Torque display device for four-wheel-drive vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a state of torque distributed to each wheel of a four-wheel-drive vehicle with high accuracy and furthermore to eliminate discomfort of a driver during displaying the torque.SOLUTION: A torque display device for a four-wheel-drive vehicle comprises torque display means If and Ir which are composed of a plurality of segments S and respectively correspond to a plurality of wheels Wf and Wr to which torque different from each other can be distributed, the torque display means If and Ir are configured in such a way that the number of segments S lighted according to an increase in the torque distributed to the wheel Wf and Wr increases and the number of segments S lighted according to reduction in the torque distributed to the wheels Wf and Wr reduces. The torque display device for a four-wheel-drive vehicle further comprises exceptional processing means M2 performing exceptional processing of torque display, so that discomfort of a driver can be eliminated during displaying the torque.SELECTED DRAWING: Figure 3

Description

  The present invention is provided with a torque display means comprising a plurality of segments corresponding to each of a plurality of wheels capable of distributing different torques to each other, and the torque display means responds to an increase in torque distributed to the wheels. The present invention relates to a torque display device for a four-wheel drive vehicle in which the number of segments to be lit increases and the number of segments to light decreases as the torque distributed to the wheels decreases.

  The ratio of the torque distributed to the rear wheels out of the torque output by the engine is set as the basic distribution ratio according to the static load distribution of the front wheels and the rear wheels, and when the front wheel speed exceeds the rear wheel speed, Increase the distribution ratio to increase the ratio of torque distributed to the rear wheels. Conversely, if the rear wheel rotation speed exceeds the front wheel rotation speed, decrease the basic distribution ratio to increase the torque distribution ratio to the front wheels. A four-wheel drive vehicle in which the difference between the front wheel speed and the rear wheel speed is converged to zero by increasing the speed is known from Patent Document 1 below.

Japanese Patent Laying-Open No. 2015-77906

  By the way, such a four-wheel drive vehicle includes a torque display device that allows the driver to visually recognize the magnitude of torque distributed to the four wheels. A conventional torque display device is provided on a liquid crystal screen, and includes, for example, five segments arranged in series for each wheel. Assuming that the maximum torque that can be distributed to one wheel is 100%, all segments are turned off when the torque command value is 0%, and when the torque command value is greater than 0% and less than 20%. One segment is lit, two segments are lit when the torque command value is greater than 20% and less than 40%, and three segments when the torque command value is greater than 40% and less than 60% When the torque command value is greater than 60% and less than 80%, 4 segments are lit. When the torque command value is greater than 80%, all 5 segments are lit. Yes.

  However, in such a torque display device, since the displayed torque is discrete, there is a problem that the magnitude of the torque distributed to each wheel cannot be accurately displayed.

  The present invention has been made in view of the above circumstances, and aims to accurately display the state of torque distributed to each wheel of a four-wheel drive vehicle and to eliminate the driver's uncomfortable feeling during torque display. To do.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided torque display means comprising a plurality of segments corresponding to each of a plurality of wheels capable of distributing different torques to each other, The torque display means is a four-wheel drive in which the number of segments that light up increases as the torque distributed to the wheels increases, and the number of segments that light up decreases as the torque distributed to the wheels decreases. A torque display device for a vehicle, comprising exception processing means for performing exceptional processing of torque display, and a first torque threshold when all the segments are turned off and a second torque when one of the segments is turned on When the hysteresis is set between the threshold value and the torque distributed to the wheels with the accelerator pedal depressed, the exception processing is performed. Means the torque display system for a four wheel drive vehicle, characterized in that for holding the one segment to the lighting state is proposed.

  According to the invention described in claim 2, torque display means comprising a plurality of segments is provided corresponding to each of the plurality of wheels capable of distributing different torques to each other, and the torque display means includes the wheels. This is a torque display device for a four-wheel drive vehicle in which the number of segments to be lit increases in accordance with an increase in torque allocated to the wheel and the number of segments to be lit decreases in response to a decrease in torque allocated to the wheels. And an exception processing means for performing an exceptional process of torque display, wherein the exception processing means limits the maximum number of lighted segments to one when the accelerator opening is equal to or less than a predetermined value. A drive vehicle torque display device is proposed.

  According to a third aspect of the present invention, there is provided torque display means comprising a plurality of segments corresponding to each of the plurality of wheels capable of distributing different torques to each other, and the torque display means comprises the wheels This is a torque display device for a four-wheel drive vehicle in which the number of segments to be lit increases in accordance with an increase in torque allocated to the wheel and the number of segments to be lit decreases in response to a decrease in torque allocated to the wheels. Provided with an exception handling means for performing an exceptional process of torque display, when the shift position is a parking position or a neutral position, or when the accelerator pedal is not depressed and the brake pedal is depressed, or the accelerator pedal The vehicle continues to decelerate without being depressed or the brake pedal is depressed for a predetermined time When the said exception processing means is a torque display system for a four wheel drive vehicle, characterized in that turns off all of the segments are proposed.

  The front wheel Wf and the rear wheel Wr of the embodiment correspond to the wheel of the present invention, and the exception processing unit M2 of the embodiment corresponds to the exception processing means of the present invention.

  According to the configuration of the first aspect, the torque display means including a plurality of segments is provided corresponding to each of the plurality of wheels capable of distributing different torques to each other, and the torque display means is configured to display the torque distributed to the wheels. As the number of segments that light up increases as the number increases, the number of segments that light up decreases as the torque distributed to the wheels decreases, allowing the driver to recognize the distribution of torque to each wheel Can do.

  In addition, an exception processing means for performing exceptional processing of torque display is provided, and hysteresis is set between the first torque threshold when all segments are turned off and the second torque threshold when one segment is turned on. Thus, when the torque distributed to the wheels with the accelerator pedal depressed falls below the first torque threshold, the exception handling means keeps one segment in a lit state, so that the driver steps on the accelerator pedal. It is possible to avoid a situation where all segments are turned off in spite of being out of order and to eliminate the driver's uncomfortable feeling.

  According to the second aspect of the present invention, when the accelerator opening is less than or equal to a predetermined value, the exception processing means limits the maximum number of segments to be lit, so that when the air conditioner is operated, or from the deceleration fuel cut When cranking the engine to return, it is possible to prevent the driver from feeling uncomfortable by preventing a plurality of segments from being turned on instantaneously even though the driver hardly presses the accelerator pedal. it can.

  According to the third aspect of the present invention, when the shift position is the parking position or the neutral position, when the brake pedal is depressed without the accelerator pedal being depressed, or when the accelerator pedal is depressed. If the state where the vehicle is decelerating or the state where the brake pedal is depressed continues for a predetermined time, the above exception handling means turns off all the segments, so one segment turns on or off. The display can be prevented from becoming unstable, and the driver's uncomfortable feeling can be resolved.

The figure which shows the whole structure of a four-wheel drive vehicle. The figure which shows the torque display apparatus on a display. The block diagram of the electronic control unit which comprises a torque display apparatus. Explanatory drawing of the determination process of the lighting stage of a torque display apparatus. Explanatory drawing of the annealing process by a display process part. The figure which shows the threshold value which determines 0th step and 1st step from the command value of front wheel distribution torque. The time chart explaining a 1st exception process. The time chart explaining the 3rd exception processing.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the four-wheel drive vehicle of the present embodiment is provided integrally with an engine E mounted horizontally on the front of the vehicle body, a transmission T connected to the engine E, and the transmission T. A differential gear D is provided, and front drive shafts Sf, Sf extending left and right from the differential gear D are connected to left and right front wheels Wf, Wf which are main drive wheels. Further, left and right clutches C and C are connected to the rear end of propeller shaft Sp extending rearward from differential gear D, and rear drive shafts Sr and Sr extending left and right from left and right clutches C and C are left and right rear wheels. Connected to wheels Wr and Wr.

  Therefore, by increasing the fastening force of the left and right clutches C, C, the torque distributed to the left and right rear wheels Wr, Wr increases and the torque distributed to the left and right front wheels Wf, Wf decreases. Assuming that the total torque generated by the engine E is 100%, the rear wheel distribution torque is controlled in the range of 70% to 30%, for example, and the front wheel distribution torque changes in the range of 30% to 70% accordingly.

  Further, when the left and right clutches C and C have the same fastening force, the same torque is distributed to the left and right rear wheels Wr and Wr. The torque can be distributed to the left and right rear wheels Wr, Wr at an arbitrary ratio in the range of 0% to 100%.

  FIG. 2 shows a torque display device on a liquid crystal screen provided in a meter panel. This torque display device is provided with four rod-shaped torque display means If, If, Ir, Ir corresponding to the left and right front wheels Wf, Wf and the left and right rear wheels Wr, Wr, respectively, and the torque display means If, If, The magnitude of the torque of the wheel is represented by the height of the illuminated portion of Ir and Ir. Each torque display means If, If, Ir, Ir is divided into five segments S arranged in series, and each segment S is composed of ten sub-segments s. Segments s... Enable almost continuous display in 51 steps from zero torque distribution amount (all segments S... Are turned off) to maximum torque distribution amount (all segments S... Are lit).

  As shown in FIG. 3, the electronic control unit U that constitutes the torque display device that controls the lighting of the torque display means If, If, Ir, and Ir includes a stage number determination processing unit M1 and an exception processing unit M2 that is an exception processing unit. And a display processing unit M3. The step number determination processing unit M1 includes a torque ratio calculation unit m1, a front side step number determination unit m2, and a rear side step number determination unit m3. The exception processing unit M2 includes a front side exception processing unit m4 and a rear side exception processing unit m5. The display processing unit M3 includes a front display speed limiting unit m6 and a rear display speed limiting unit m7.

  The total torque of the left and right front wheels Wf, Wf and the left and right rear wheels Wr, Wr generated by the engine E and the basic distribution ratio of the rear wheel distribution torque are input to the torque ratio calculation unit m1 of the stage number determination processing unit M1. The front side display speed limiting unit m6 of the display processing unit M3 is connected to the torque display means If, If of the left and right front wheels Wf, Wf, and the rear side display speed limiting unit m7 of the display processing unit M3 is connected to the left and right rear wheels Wr, It is connected to the torque display means Ir, Ir of Wr.

  Next, the operation of the stage number determination processing unit M1 will be described.

  For the rear wheel distribution torque, a basic distribution ratio (for example, 40%) is set in advance based on the vehicle body weight distribution (static load) with respect to the front wheels Wf, Wf and the rear wheels Wr, Wr. 60% of the total torque generated by is distributed to the left and right front wheels Wf, Wf, and 40% of the total torque is distributed to the left and right rear wheels Wr, Wr. When the rotational speed of the front wheels Wf, Wf exceeds the rotational speed of the rear wheels Wr, Wr, the basic distribution ratio is increased from 40% to increase the torque distribution amount to the rear wheels Wr, Wr, thereby increasing the front wheels The rotational speed difference between Wf and Wf and the rear wheels Wr and Wr is converged to zero. Conversely, when the rotational speed of the rear wheels Wr, Wr exceeds the rotational speed of the front wheels Wf, Wf, by decreasing the basic distribution ratio from 40% and increasing the torque distribution amount to the front wheels Wf, Wf, The rotational speed difference between the front wheels Wf, Wf and the rear wheels Wr, Wr is converged to zero.

  The torque ratio calculation unit m1 calculates the front-side ratio by dividing the front wheel distribution torque by the maximum value of torque that can be distributed to the front wheels Wf, Wf. The front side ratio is calculated for the left and right front wheels Wf and Wf, respectively, but since the same torque is distributed to the left and right front wheels Wf and Wf, the front side ratio is the same value for the left and right front wheels Wf and Wf. become. The torque ratio calculation unit m1 calculates the rear side ratio by dividing the rear wheel distribution torque by the maximum value of torque that can be distributed to the rear wheels Wr and Wr. The rear side ratio is calculated for each of the left and right rear wheels Wr, Wr. However, since different torques may be distributed to the left and right rear wheels Wr, Wr, the rear side ratio is determined as the left and right rear wheels Wr, Wr. It is not always the same value for Wr.

  In order to control the lighting of the torque display means If and If of the left and right front wheels Wf and Wf, the front-side stage number determining unit m2 compares the filtered front wheel distribution torques with the maximum torque that can be distributed to the front wheels Wf. Thus, the lighting stage of the torque display means If, If is determined (first stage numbering). Specifically, when each front wheel distribution torque is 0% of the maximum torque that can be distributed to each front wheel Wf, the number of lighting stages is set to the 0th stage, all the segments S are turned off, and the front wheel distribution torque is less than 0%. When it is large and less than 20%, one segment S is lit with the number of lighting stages as the first stage, and when the front wheel distribution torque is larger than 20% and less than 40%, the number of lighting stages is set as the second stage. When segments S and S are lit and the front wheel distribution torque is greater than 40% and less than 60%, the three segments S are lit with the number of lighting stages as the third stage, and the front wheel distribution torque is greater than 60%. When it is 80% or less, the number of lighting stages is set to the fourth stage and the four segments S are turned on. When the front wheel distribution torque is greater than 80%, the number of lighting stages is set to the fifth stage and the five segments S are set. Light.

  As shown in FIG. 4, the front side stage number determination unit m2 further includes a counter that counts the duration of each lighting stage, and the final lighting stage is determined when the count time of the counter continues for a predetermined time ( Second stage number).

  The determination of the lighting step number of the left and right front wheels Wf, Wf by the front side step number determining unit m2 has been described above, but the torque display unit of the left and right rear wheels Wr, Wr by the rear side step number determining unit m3. Ir and Ir lighting stages are determined in the same manner.

  Next, the operation of the display processing unit M3 will be described.

  Since the lighting stage determined by the stage number determination processing unit M1 changes in a stepwise manner in the segment S..., When the lighting of the torque display means If, If, Ir, Ir is controlled using the lighting stage as it is, one segment is obtained. The ten sub-segments s... Included in S may be turned on or off all at once, and the actual torque change may not be displayed with high accuracy. However, according to the present embodiment, the front-side display speed limiting unit m6 smoothly changes the step-like change between the lighting stages as shown in FIG. Thereby, a total of 50 sub-segments s... Are turned on or off one by one continuously, and the actual torque change can be displayed with high accuracy.

  In addition, if the smoothing process is performed at the same rate when making step-like changes between each lighting stage, the convergence time becomes long when there are many stages that change, and the actual torque change cannot be accurately displayed. There is a fear. However, according to the present embodiment, the sub-segment s... Is turned on / off so that the annealing process is completed at a constant time T1 (see FIG. 5) regardless of the number of changing stages, that is, when the number of changing stages is large. By increasing the speed (decreasing the lighting / extinguishing time interval) and decreasing the lighting / extinguishing speed of the sub-segment s ... when the number of change steps is small, the convergence time becomes excessive. Is preventing. For example, FIG. 5 shows that the five-stage change from the fifth stage to the zeroth stage and the two-stage change from the second stage to the zeroth stage are completed at the same time T1.

  Next, the operation of the exception processing unit M2 will be described.

  As shown in FIG. 6, hysteresis is set for the threshold value for determining the 0th stage and the 1st stage from the command value of the front wheel distribution torque, and the command value of the front wheel distribution torque is decreased to set the first torque threshold value LO. If it falls below, it changes from the first stage to the 0th stage, and if it exceeds a second torque threshold value HI that is larger than the first torque threshold value LO, it changes from the 0th stage to the first stage. As a result, there is a situation in which the torque display means If, If of the front wheels Wf, Wf, which are the main driving wheels, displays the 0th stage and all the segments S ... are turned off even though the driver steps on the accelerator pedal. May occur and give the driver a sense of incongruity.

  Therefore, in the “first exception processing” of the present embodiment, as shown in FIG. 7, the front-side exception processing unit m4 and the rear-side exception processing unit m5 have the input display stage changed from the first stage to the zeroth stage. However, when the accelerator pedal is depressed, the output display stage is held at the first stage, and when the release counter counts a predetermined time from when the driver releases the accelerator pedal, the output display stage is set to the first stage. By executing the first exception process that changes from the first stage to the zeroth stage, the driver feels uncomfortable.

  In addition, when operating the air conditioner, or when cranking the engine E to return from the idle stop state when the vehicle is stopped, the total torque is not accurately calculated, so the driver does not step on the accelerator pedal, The display stage instantaneously reaches the second stage or the third stage, which may give the driver a feeling of strangeness.

  Therefore, in the “second exception processing” of the present embodiment, the front-side exception processing unit m4 and the rear-side exception processing unit m5 are in the output display stage when the driver does not step on the accelerator pedal more than a predetermined amount. By executing the second exception process that limits the upper limit to the first stage, the driver feels uncomfortable.

  Further, when the vehicle is decelerated from a vehicle speed up to about 60 km / h, the front wheels Wf and Wf and the rear wheels Wr and Wr depend on whether the engine brake is moderately decelerated or the brake is suddenly decelerated. Since the vehicle body weight distribution changes, the front wheel distribution torque and the rear wheel distribution torque become unstable. For this reason, the display stage of the torque display means If, If for the front wheels Wf, Wf becomes the 0th stage or the 1st stage. May not be stable and may give the driver a sense of incongruity.

Therefore, in the “third exception processing” of the present embodiment, the front-side exception processing unit m4 and the rear-side exception processing unit m5 force the display stage of the torque display means If, If of the front wheels Wf, Wf to the 0th stage. By setting to, the driver feels uncomfortable. To explain this process in detail,
Zeroization condition 1: Shift position is parking position or neutral position Zeroization condition 2: Accelerator pedal is OFF and brake pedal is ON Zeroization condition 3: Deceleration state is predetermined when accelerator pedal is OFF When one of the three conditions that the time continues or the brake pedal ON state continues for a predetermined time is satisfied, the display stage of the torque display means If, If of the front wheels Wf, Wf is forcibly set to the 0th stage. (All segments S ... are turned off). The zeroing condition 3 is canceled when the following zeroing cancellation condition is satisfied, and the forced setting of the 0th stage is canceled.

Zeroization release condition: The vehicle speed drops below a threshold value or the accelerator pedal ON state continues for a predetermined time. FIG. 8 forcibly sets the display stage of the torque display means If, If of the front wheels Wf, Wf to the 0th stage. It is a time chart which shows an example of the 3rd exception process set to. At time t1, the shift position becomes the P range or N range, and the zeroing condition 1 is satisfied. At time t2, the zeroing condition 1 is not satisfied, and the forced setting of the 0th stage is cancelled. When the accelerator is turned off at time t3, the brake is turned on and the zeroing condition 2 is satisfied, and the deceleration state with the accelerator OFF at time t4 continues for the time T2, and the zeroing condition 3 is satisfied. The display stage of the torque display means If, If of Wf, Wf is forcibly set to the 0th stage. At time t5, the accelerator ON state continues for time T3, so that the zeroization condition 3 is not satisfied, and the forced setting of the 0th stage is cancelled.

  In addition, the state where the accelerator is OFF and the vehicle is decelerated at time t6 continues for time T4, and the zeroization condition 3 is satisfied, so that the display stage of the front wheel Wf, Wf torque display means If, If is forcibly set to the 0th stage Set to Then, the state where the vehicle speed is equal to or lower than the threshold value continues at time t7 for a time T5, so that the zeroization condition 3 is not satisfied and the forced setting of the 0th stage is cancelled.

  In the above-mentioned “first exception processing”, “second exception processing”, and “third exception processing”, “third exception processing” is executed with the highest priority, and “second exception processing” is next. By executing with priority and executing “first exception handling” last, mutual interference between the three exception handling is prevented.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, the number of segments S ... of each torque display means If, Ir is not limited to five, and the number of sub-segments s ... included in each segment S is not limited to ten.

If torque display means Ir torque display means S segment s subsegment Wf front wheel (wheel)
Wr Rear wheel (wheel)

Claims (3)

Torque display means (If, Ir) comprising a plurality of segments (S) is provided corresponding to each of the plurality of wheels (Wf, Wr) capable of distributing different torques to each other, and the torque display means (If, Ir). ) Increases in the number of segments (S) that light up in accordance with an increase in torque distributed to the wheels (Wf, Wr), and in response to a decrease in torque distributed to the wheels (Wf, Wr). A torque display device for a four-wheel drive vehicle in which the number of segments (S) to be lit decreases.
Exception processing means (M2) for performing exceptional processing of torque display is provided,
Hysteresis is set between the first torque threshold when all the segments (S) are turned off and the second torque threshold when one of the segments (S) is turned on, and the accelerator pedal is depressed. The four-wheel drive characterized in that the exception processing means (M2) holds the one segment (S) in a lighting state when the torque distributed to the wheels in the state falls below the first torque threshold. Vehicle torque display device. Torque display means (If, Ir) comprising a plurality of segments (S) is provided corresponding to each of the plurality of wheels (Wf, Wr) capable of distributing different torques to each other, and the torque display means (If, Ir). ) Increases in the number of segments (S) that light up in accordance with an increase in torque distributed to the wheels (Wf, Wr), and in response to a decrease in torque distributed to the wheels (Wf, Wr). A torque display device for a four-wheel drive vehicle in which the number of segments (S) to be lit decreases.
Exception processing means (M2) for performing exceptional processing of torque display is provided,
The torque display device for a four-wheel drive vehicle, wherein the exception processing means (M2) limits the maximum number of lighting of the segment (S) to one when the accelerator opening is equal to or less than a predetermined value. Torque display means (If, Ir) comprising a plurality of segments (S) is provided corresponding to each of the plurality of wheels (Wf, Wr) capable of distributing different torques to each other, and the torque display means (If, Ir). ) Increases in the number of segments (S) that light up in accordance with an increase in torque distributed to the wheels (Wf, Wr), and in response to a decrease in torque distributed to the wheels (Wf, Wr). A torque display device for a four-wheel drive vehicle in which the number of segments (S) to be lit decreases.
Exception processing means (M2) for performing exceptional processing of torque display is provided,
If the shift position is a parking position or neutral position, or if the accelerator pedal is not depressed and the brake pedal is depressed, or if the accelerator pedal is not depressed and the vehicle is decelerating or if the brake pedal is The torque display device for a four-wheel drive vehicle, wherein the exception processing means (M2) turns off all the segments (S) when the stepped state continues for a predetermined time.

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