JP3625082B2 - Power steering device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a power steering device that reduces the steering force of a driver by directly applying the power of an actuator (hydraulic or electric motor) to a steering system, and in particular, power steering that controls the power of the actuator in accordance with the state of an automatic transmission. Relates to the device.
[0002]
[Prior art]
In a conventional power steering apparatus, for example, an electric power steering apparatus, a plurality of target current signal characteristic data using a vehicle speed as a parameter is stored in advance in response to a steering torque signal by detecting a manual steering torque of a driver. It is known that an electric motor control signal is generated by selecting one of the current signal characteristics, and the electric motor torque is applied to the steering system as a steering assist force by driving the electric motor through the electric motor driving means. Yes.
[0003]
In addition, the conventional electric power steering apparatus sets a steering assist force large in the low vehicle speed range to improve steering lightness, while setting a steering assist force small in the high vehicle speed region to oversteer the steering. By preventing this, the vehicle behavior is stabilized.
[0004]
Normally, multiple target current signal characteristics data with the vehicle speed as a parameter is set to suit the average driver's preference, but the vehicle speed is parameterized so that it can accommodate the preference of the driver with high sporting frequency. In response to sports driving, a plurality of other target current signal characteristic data and an external changeover switch are provided, and by operating this external changeover switch, it is possible to switch the steering characteristic of the average driver and the steering characteristic of the sports run. Those configured to be known are also known. (See JP-A-59-100059)
[0005]
[Problems to be solved by the invention]
The conventional electric power steering device is configured to be capable of switching the steering characteristics of an average driver and the steering characteristics of sports driving by operating an external changeover switch, but because the operation of the changeover switch is required, In many cases, the operation is troublesome or the operation is forgotten, and the frequency of use is low, so that it is not used effectively.
[0006]
In general, automatic transmission vehicles (hereinafter referred to as AT vehicles) have 1 (low), 2 (second), 3 (third), and D (D3 and D3) at the shift position of the shift lever of the automatic transmission. D4) and the like, and is frequently set to the shift position D3 or 2 (second) range when traveling on an upwinding road or downwinding road in a mountainous region or when traveling on a circuit or the like.
[0007]
This is because the engine brake is effective because the engine speed of the shift position D3 and 2 (second) range is high, and the generated torque of the engine is high.
[0008]
However, when the winding road frequency is high, the steering rotation angle increases and the behavior of the vehicle also increases. Therefore, a steering feeling that is more responsive than when driving in urban areas is preferred, and it is suitable for vehicle behavior. Steering characteristics are desired.
[0009]
The present invention has been made to solve such problems, and its purpose is to automatically switch the steering characteristics in conjunction with the shift characteristics of the automatic transmission, and to have excellent operability that provides a responsive steering feeling. Another object is to provide a power steering device.
It is another object of the present invention to provide a power steering apparatus that can manually switch part of the shift characteristics and link the steering characteristics to the shift characteristics suitable for the sports driving mode to obtain a more responsive steering feeling.
Note that the power steering device is an electric power steering device and a hydraulic power steering device.
[0010]
[Means for Solving the Problems]
To solve the above problemsThe present inventionThe control means of the power steering device according to the invention changes the characteristic of the control signal based on the signal from the shift position detection means for detecting the shift position of the automatic transmission provided in the vehicle,The automatic transmission can be switched from the predetermined shift position in the automatic mode to the manual mode. When the automatic transmission is switched to the manual mode, the control means switches from the plurality of target signal characteristic data to the automatic mode based on the signal from the shift position detection means. Select a characteristic data value that is smaller than the corresponding characteristic data valueIt is characterized by that.
[0011]
Also,The present inventionThe power steering device according toSelect a characteristic data value smaller than the characteristic data value corresponding to the automatic mode from multiple target signal characteristic data at the time of at least one shift position other than the low gear and the top gear among the shift positions in the manual mode.It is characterized by that.
[0012]
[Action]
The present inventionSince the control means of the power steering device according to the invention changes the characteristic of the control signal based on the signal from the shift position detection means for detecting the shift position of the automatic transmission provided in the vehicle, the same steering torque and the same vehicle speed are obtained. Correspondingly, a plurality of different steering characteristics can be obtained.
[0013]
Also,The present inventionIn the power steering apparatus according to the present invention, the automatic transmission can be switched from the predetermined shift position in the automatic mode to the manual mode. When the automatic transmission is switched to the manual mode, the control means is configured to output a plurality of targets based on the signal from the shift position detection means. Since a characteristic data value smaller than the characteristic data value corresponding to the automatic mode is selected from the signal characteristic data, it is possible to obtain a steering feeling that is more responsive during sports running.
[0014]
【Example】
Embodiments of the present invention will be described below with reference to the accompanying drawings.
First, an embodiment in which the present invention is applied to an electric power steering apparatus will be described.
FIG. 1 is an overall configuration diagram of an electric power steering apparatus according to the present invention.
The electric power steering apparatus 1 includes a steering wheel 2, a steering shaft 3, a hypoid gear 4, a rack and pinion mechanism 5 including a pinion 5a and a rack shaft 5b, a tie rod 6, a front wheel 7 of a steering wheel, and an actuator that generates a steering assist force. The steering torque sensor 10 that detects the steering torque acting on the motor 8 and the steering wheel 2 and outputs the steering torque signal T converted into the electrical signal corresponding to the steering torque, detects the vehicle speed, and corresponds to the vehicle speed A vehicle speed sensor 11 that outputs a vehicle speed signal V converted into an electric signal, and a D range (D3 range or D3 range and 2 ranges) of an automatic transmission provided in an AT vehicle are detected, and a shift position D range is detected. Shift position signal P converted to an electrical signal corresponding to The position detector 15 sets a plurality of different steering characteristic data values corresponding to the same steering torque signal T and vehicle speed signal V, selects the steering characteristic data value corresponding to the shift position signal P, and sets the electric motor 8 The motor control means 12, the motor drive means 13, and the motor current detection means 14 which comprise the control means to drive and control are provided.
[0015]
When the steering wheel 2 is steered, a steering torque sensor 10 provided on the steering shaft 3 detects the steering torque, and supplies a steering torque signal T converted to an electric signal to the motor control means 12.
The steering torque applied to the steering shaft 3 is converted from the rotational force of the pinion 5a to the axial movement of the rack shaft 5b via the rack and pinion mechanism 5, and the front wheel 7 is steered via the tie rod 6. Change.
[0016]
On the other hand, the vehicle speed sensor 11 detects the speed of the vehicle, converts it into a corresponding electrical signal, and supplies the vehicle speed signal V to the motor control means 12.
The shift position detection means 15 detects the shift position D range of the shift lever of the AT vehicle with a corresponding electric signal (for example, a voltage signal), and provides the shift position signal P to the motor control means 12.
[0017]
The motor control means 12 sends to the motor drive means 13 based on the steering torque signal T, the vehicle speed signal V and the shift position signal P, for example, a PWM (pulse width modulation) motor control signal V._OThe motor drive means 13 supplies the motor control signal V_OMotor voltage V corresponding to_MTo drive the electric motor 8.
The electric motor torque generated by the electric motor 8 is converted into a steering assist torque (assist torque) boosted via the hypoid gear 4 and acts on the steering shaft 3.
[0018]
As described above, the electric power steering apparatus 1 causes the power of the electric motor to act on the steering system, reduces the steering torque of the driver applied to the steering wheel 2, and also increases the power of the electric motor according to the vehicle speed and the shift position of the automatic transmission. To give the driver appropriate steering characteristics in accordance with the traveling state of the AT vehicle.
[0019]
Figure 2The present inventionIt is a principal block block diagram of the electric power steering device concerning.
In FIG. 2, the electric power steering apparatus 1 includes a steering torque sensor 10, a vehicle speed sensor 11, an electric motor control means 12, an electric motor drive means 13, an electric motor 8, an electric motor current detection means 14, and the like.
The motor control means 12 is supplied with a shift position signal P from a shift position detection means 15 mounted on the automatic transmission 16 of the AT vehicle, and the shift position (1: low, 2: second) of the automatic transmission 16 is supplied. 3: third, D: range of D3, D4, etc.), the steering characteristics are controlled.
[0020]
The steering torque sensor 10 is composed of, for example, a differential transformer, and supplies a steering torque signal T converted to an analog electric signal to the motor control means 12 corresponding to the direction and magnitude of the driver's steering force.
The vehicle speed sensor 11 is composed of, for example, a speedometer including a rotating disk having a slit and a photocoupler, and supplies a vehicle speed signal V detected by a pulse electric signal having a period proportional to the vehicle speed to the motor control means 12.
[0021]
Here, the shift position detecting means of the automatic transmission will be described.
FIG. 9 is a layout diagram of the automatic transmission, FIG. 10 is a shift position indicator image diagram, and FIG. 11 is a configuration diagram of the shift position detecting means.
In FIG. 9, the shift lever 17 of the automatic transmission 16 is disposed in the vicinity of the driver's seat, and the shift position signal P corresponding to the shift position is detected from the shift position detection means 15 of FIG.
Further, the shift position indicator 18 shown in FIG. 10 is arranged on the front panel or the like in the passenger compartment to visually display the shift position.
[0022]
The shift position detecting means 15 shown in FIG. 11 is composed of, for example, a potentiometer, and is formed in a fan-shaped shape centering on the O point, the movable contact portion 53 rotating around the O point in conjunction with the shift lever 17 shown in FIG. A voltage detection pattern 51, an electrode pattern 52A formed on a sector and connected to a power source (for example, + 5V) at both ends and a ground pattern 52B connected to a vehicle body ground (GND), and a resistor pattern (for example, a potentiometer) ), And the brush 53A provided on the movable contact portion 53 rotates while being in contact with the voltage detection pattern 51 and the variable resistance means 52, so that the shift position (1: low, 2: Detection voltage V corresponding to 2nd, 3rd, 3rd, D: D3, D4, etc._K(Voltage V_K-Between GND).
[0023]
In addition to the ones corresponding to automatic shifts in the range of 1: low, 2: second, 3: third, D: D3, D4, etc., the shift position of AT cars is for shift control more suitable for sports driving. For example, a switch provided on the shift lever from a state where the shift lever switch is set to the shift position D4 range from the shift position D3 range so that it can be operated and set manually. Can be manually set by operating the D3, D4 range of the CVT (automatic transmission device), etc., and fixed automatic transmission patterns such as D3 and D4 can be manually set Change to a gear shift pattern to achieve a sport driving pattern in the driving state preferred by the driver, for example, manual gear shifting. .
[0024]
Further, the shift position detection means 15 includes a determination means (not shown), and a detection voltage V of the shift position D3 or 2 (second) range._KIs detected, for example, an H level shift position signal P is supplied to the switching means 24 of the motor control means 12.
[0025]
The motor control means 12 is based on a microprocessor and is composed of various arithmetic functions, memory, processing functions and the like that are operated by an instruction execution program of a soft program. The target signal characteristic data generating means (A) 22 and the target signal characteristic data generating means (B) A target signal setting unit 21, a switching unit 24, a deviation determination unit 25, and a drive control unit 26 are provided.
[0026]
The target signal characteristic data generating means (A) 22 and the target signal characteristic data generating means (B) 23 are each provided with a memory such as a ROM, and the steering torque signal T and the vehicle speed sensor 11 detected by the steering torque sensor 10 are detected. The vehicle speed signal V of the detected signal is taken in and each signal V processed in parallel is processed._D, T_DVehicle speed signal V preset in each memory based on_DSteering torque signal T_D-Target current signal I_MSFrom the characteristic data of the steering torque signal T_DTarget current signal I corresponding to_MS(I_MA, I_MB) Read data, target current signal I_MAAnd target current signal I_MBIs provided to the switching means 24.
[0027]
FIG. 3 shows a block diagram of a main part of one embodiment of the target signal setting means of FIG.
In this embodiment, two storage means for storing the target current signal data are provided, and the target current signal data from any one of the storage means is selected based on the shift position signal P from the characteristic data set in each storage means. It will be selectable.
In FIG. 3, the target signal setting means 21 has a target signal characteristic data generating means (A) 22 having a sport running pattern data storage means 22A and a data access means 22B, a normal running pattern data storage means 23A and a data access means 23B. Target signal characteristic data generating means (B) 23 is provided.
[0028]
The data access means 22B receives the steering torque signal T_DAnd vehicle speed signal V_D6A, an access signal is sent to the sport running pattern data storage means 22A, and the vehicle speed signal V of the sport running pattern is set by the automatic shift shown in FIG._D(V_L, V_M, V_H) As a parameter for steering torque signal T_D-Target current signal (I_MA) Corresponding target current signal I from the characteristic data of characteristic diagram_MAData is read and target current signal I for sports driving with automatic shifting_MAIs provided to one terminal of the switching means 24.
[0029]
Similarly to the data access means 22B, the data access means 23B has a steering torque signal T._DAnd vehicle speed signal V_DAnd the vehicle speed signal V of the normal running pattern with the automatic shift shown in FIG._D(V_L, V_M, V_H) As a parameter for steering torque signal T_D-Target current signal (I_MB) Corresponding target current signal I from the characteristic data of characteristic diagram_MBData is read out and the target current signal I during normal driving with automatic shift_MBData is provided to the other terminal of the switching means 24.
[0030]
The sport running pattern data storage means 22A and the normal running pattern data storage means 23A are each constituted by a memory such as a ROM, and the vehicle speed signal V shown in FIGS. 6 (a) and 6 (b) is set in advance._D(V_L, V_M, V_H) As a parameter for steering torque signal T_D-Target current signal (I_MA, I_MB) The characteristic data of the characteristic diagram is stored, and based on the access signals from the data access means 22B and the data access means 23B, the target current signal I during sports running_MAData and target current signal I during normal driving_MBOutput data.
[0031]
The target current signal I of the automatic / sport running pattern shown in FIG._MACharacteristics and target current signal I of the automatic / normal running pattern shown in FIG._MBAll characteristics are the same vehicle speed signal V_DAnd the same steering torque signal T_DIn order to increase the driver's steering response during sports driving, especially by setting the characteristic value of the automatic / sport driving pattern to be smaller than the characteristic value of the automatic / normal driving pattern. Can do.
[0032]
The switching means 24 is constituted by an electronic switch or a switch function of software control. From the shift position detecting means 15 shown in FIG. 11, an H level shift position signal P (P) corresponding to the shift position D3 or 2 (second) range._S) Is provided, the target current signal I of the automatic / sport driving pattern_MAAnd L level shift position signal P (P) corresponding to shift position 1 (low), D4 other than shift position D3 or 2 (second) range._T) Is provided, the target current signal I for automatic and normal driving patterns_MBIn both cases, the target current signal I_MSIs supplied to the deviation determining means 25 shown in FIG.
[0033]
In this way, the target signal setting means 21 is the target current signal characteristic data (I_MA), Target current signal characteristic data (I_MB) Is stored in the sport running pattern data storage means 22A and the normal running pattern data storage means 23A, so that the shift position signal P (P_S, P_T) Based on the target current signal I of the sport running pattern with automatic shifting_MAOr, the target current signal I of the normal running pattern with automatic shifting_MBCan be output.
[0034]
The deviation determining means 25 is constituted by a subtractor or a subtraction function of software control, and the target current signal I_MSMotor current detection signal I fed back from motor current detection means 14_MDThe deviation signal ΔI (= I_MS-I_MD) Is output to the drive control means 26.
[0035]
The drive control means 26 uses the deviation signal ΔI (= I_MS-I_MD) Proportional (P), integral (I) and derivative (D) calculation, PID controller for processing, and on to control the direction and magnitude of the generated torque of the motor 8 based on the signal from this PID controller Motor control signal V, which is a hybrid signal of signals and PWM (pulse width modulation) signals_OIncluding a signal generator for generating electric motor control signal V_OIs supplied to the electric motor drive means 13 and the deviation signal ΔI (= I_MS-I_MD) Is quickly and stably controlled to 0.
[0036]
When the motor 8 is a DC motor, the motor driving means 13 is constituted by a bridge circuit composed of four FETs (field effect transistors), and an electric motor control signal V such as an ON signal or PWM (pulse width modulation) signal._OThe drive voltage of the FET (field effect transistor) is controlled by the motor voltage V having the drive direction and magnitude._M To drive the electric motor 8.
[0037]
The electric motor 8 uses, for example, a DC electric motor, a brushless motor, or the like, and an electric motor voltage V having a driving direction and a magnitude supplied from the electric motor driving means 13._MDriven by the motor voltage V_MPower corresponding to is generated, and the motor torque acts on the steering system as the steering assist force.
[0038]
The motor current detection means 14 is constituted by, for example, a current sensor using a Hall element, a detector using a resistor that detects current as voltage, and the like._MIs detected and converted to a digital signal._MDIs fed back to the deviation determining means 26 (NFB: negative feedback).
[0039]
Figure 4BookIt is a principal part block block diagram of another Example of the motor control means which concerns on invention.
In FIG. 4, an electric motor control means 30 is provided with various control means, processing means, memory, etc. for soft control based on a microprocessor, and a target current signal I for an automatic / sport running pattern._MA, And braking current signal I_DAThe target signal characteristic data generating means (A) 32 and the braking signal characteristic data generating means (A) 33 for respectively setting the target current signal I of the automatic / normal running pattern_MB, And braking current signal I_DBTarget signal characteristic data generating means (B) 35 and braking signal characteristic data generating means (B) 36, target signal setting means 31, target current signal calculating means (A) 34, target current signal calculating means ( B) 37, switching means 24, deviation calculating means 25, drive control means 26 are provided.
[0040]
The target signal characteristic data generating means (A) 32 and the target signal characteristic data generating means (B) 35 are the same as the target signal characteristic data generating means (A) 22 and the target signal characteristic data generating means (B) 23 shown in FIG. Configuration, steering torque signal T_DAnd vehicle speed signal V_DBased on the target current data I corresponding to the characteristic data of FIGS. 6 (a) and 6 (b)_MA, I_MBAnd select the target current signal I_MA, Target current signal I_MBAre provided to the target current signal calculation means (A) 34 and the target current signal calculation means (B) 37, respectively.
[0041]
The braking signal characteristic data generating means (A) 33 and the braking signal characteristic data generating means (B) 36 are provided with a memory such as a ROM, and the vehicle speed signal V shown in FIGS._D(V_L, V_M, V_H) As a parameter for steering rotation speed signal N_D-Braking current signal (I_DA, I_DB) The steering rotational speed signal N detected by the steering rotational speed sensor 9 from the characteristic data in the characteristic diagram and converted into an electrical signal._DAnd vehicle speed signal V_DCorresponding braking current data I_DA, I_DBAnd select the braking current signal I_DA, Braking current signal I_DBAre provided to the target current signal calculation means (A) 34 and the target current signal calculation means (B) 37, respectively.
[0042]
In the characteristic diagram of FIG. 7, (a) corresponds to the sport running pattern by the automatic shift corresponding to the shift position D3 or 2 (second) range from the shift position detecting means 15 shown in FIG. 11, and (b) is the shift. Automatic shifts corresponding to shift positions 1 (low) and D4 other than the positions D3 and 2 (second) range are made to correspond to the normal running pattern, and the same vehicle speed signal V_DAnd steering rotation speed signal N_D(A) braking current signal I_DAIs the braking current signal I of (b)_DBSet to be larger than
[0043]
The target current signal calculation means (A) 34 and the target current signal calculation means (B) 37 are provided with an addition function, a subtraction function, and a steering state signal S from the steering state determination means 38._TSwitch means for switching between the addition function and the subtraction function under the control of.
[0044]
The target current signal calculation means (A) 34 receives the steering state signal S._TIs, for example, at the H level, the target current signal I provided from the target signal characteristic data generating means (A) 32._MABraking current signal I provided from braking signal characteristic data generating means (A) 33_DADeviation (I_MA-I_DA) To calculate the target current signal I in the steering forward state_MSA(= I_MA-I_DA) Is supplied to the switching means 24.
[0045]
Further, the target current signal calculation means (A) 34 receives the steering state signal S._TIs, for example, L level, the target current signal I_MAAnd braking current signal I_DASum of (I_MA+ I_DA) To calculate the target current signal I in the steering return state._MSA(= I_MA+ I_DA) Is supplied to the switching means 24.
[0046]
The target current signal calculation means (B) 37 is also configured in the same manner as the target current signal calculation means (A) 34, and the target current signal I provided from the target signal characteristic data generation means (B) 35 in the steering forward state._MBAnd the braking current signal I provided from the braking signal characteristic data generating means (B) 36._DBDeviation (I_MB-I_DB) To calculate the target current signal I_MSB(= I_MB-I_DB) Is supplied to the switching means 24.
On the other hand, in the steering return state, the target current signal I_MBAnd braking current signal I_DBSum of (I_MB+ I_DB) To calculate the target current signal I_MSB(= I_MB+ I_DB) Is supplied to the switching means 24.
[0047]
The steering state determination means 38 is a steering torque signal T_DDirection flag F and steering rotation speed signal N_D1 is detected, and the steering state signal corresponding to the steering state is detected, for example, the steering wheel 2 shown in FIG. S_TIs supplied to the target current signal calculation means (A) 34 and the target current signal calculation means (B) 37.
For example, the detection of the steering forward state or the steering return state is determined by the signs of the flag F and the flag G. When the signs of the flag F and the flag G match (F = G), the forward state, the flag F and the flag If the G codes do not match (F ≠ G), the return state is set.
[0048]
As described above, the braking signal characteristic data generating means (A) 33 and the braking signal characteristic data generating means (B) 36 are applied to the braking current signal I corresponding to the steering rotational speed N of the steering wheel 2 operated by the driver._DA(Or braking current signal I_DB), The target current signal I corresponding to the steering torque T_MA(Or target current signal I_MB) Can be braked.
[0049]
Further, a target current signal calculating means (A) 34 and a target current signal calculating means (B) 37 are provided, and the steering state signal S from the steering state determining means 38 is provided._TBased on the target current signal I corresponding to the steering forward state or the steering returning state_MSA, I_MSBIs generated.
[0050]
The switching means 24 is constituted by an electronic switch or a switch function of software control. From the shift position detecting means 15 shown in FIG. 11, an H level shift position signal P (P) corresponding to the shift position D3 or 2 (second) range._S) Is provided, the target current signal calculation means (A) 34 side is connected and the target current signal I_MSAThe target current signal I of the sport running pattern with automatic shifting_MSIs output to the deviation determining means 25.
[0051]
On the other hand, L level shift position signal P (P) corresponding to shift position 1 (low) and D4 other than shift position D3 and 2 (second) range._T) Is provided, the target current signal calculation means (B) 37 side is connected and the target current signal I_MSBThe target current signal I of the normal running pattern with automatic shifting_MS Is output to the deviation determining means 25.
[0052]
As described above, the motor control means 30 corresponds to the sport running pattern in the automatic shift of the shift position D3 or 2 (second) of the AT car and the normal running pattern in the automatic shift other than the shift position D3 or 2 (second). Target current signal I_MA, I_MBAnd braking current signal I_DA, I_DBAnd the target current signal I corresponding to the steering forward or steering return state_MS(I_MA-I_DA, I_MB-I_DB), (I_MA+ I_DA, I_MB+ I_DB1), the finely-tuned steering characteristic corresponding to the traveling state of the vehicle can be obtained.
[0053]
In addition, the target current signal I in the sports driving mode with automatic shift and the steering-out state_MS(= I_MA-I_DA) With the automatic shift in the normal driving mode and the steering forward target current signal I_MS(I_MB-I_DB) Since a smaller value is set, the steering assist force in the sport driving mode can be reduced by automatic shifting, and a steering characteristic with a responsive feeling can be obtained.
[0054]
Further, by operating the shift lever of the AT car, branching from a predetermined shift position (for example, shift position D3 range), manually setting by manual operation, changing the fixed automatic shift pattern to the manual shift pattern, The steering characteristics of the sport driving pattern with the manual shift to suit the preference and the steering characteristics of the normal driving pattern with the manual shift are the vehicle speed signal V of the manual / sport driving pattern of FIG._DSteering torque signal T_D-Target current signal (I_MA) Characteristic diagram, vehicle speed signal V of manual / normal driving pattern of FIG. 8 (b)_DSteering torque signal T_D-Target current signal (I_MBThe data shown in the characteristic diagram can be realized by setting in advance in the ROMs of the target signal characteristic data generating means (A) 22 and the target signal characteristic data generating means (B) 23 shown in FIG.
[0055]
In addition, the target current signal I of the manual / sports driving pattern shown in FIG._MAAnd the target current signal I of the manual / normal driving pattern shown in FIG._MBEach have the same steering torque signal T_DAnd vehicle speed signal V_DOn the other hand, the target current signal I of the automatic / sport running pattern shown in FIG._MAFIG. 6B shows the target current signal I of the automatic / normal driving pattern._MBSet to a smaller value.
[0056]
Also, the characteristic data of (a) and (b) of FIG. 8 are set in advance in the ROM of the target signal characteristic data generating means (A) 32 and the target signal characteristic data generating means (B) 35 shown in FIG. Further, it is possible to realize the steering characteristics of the sport running pattern by manual shifting and the normal running pattern by manual shifting.
[0057]
Next, an embodiment in which the present invention is applied to a hydraulic power steering apparatus will be described.
FIG. 5 is an overall configuration diagram of the hydraulic power steering apparatus according to the present invention.
5, the hydraulic power steering apparatus 40 includes an actuator control unit 41 corresponding to the electric motor control unit 12 shown in FIG. 2 and an actuator driving unit 42 corresponding to the electric motor driving unit 13.
[0058]
The hydraulic power steering device 40 includes a solenoid drive unit 61 driven by an actuator drive unit 42, a variable throttle valve 62 provided between the oil supply path 73 and the hydraulic reaction chamber 63 via a communication path 74B, a variable throttle valve. The hydraulic pressure supplied from 62 urges the spool valve body 64A of the switching valve 64 to the neutral position and applies a steering torque, the switching valve 64 for switching the hydraulic pressure supplied to the power cylinder 65, the rack shaft A rack provided on the power cylinder 65 and the rack shaft 67 that moves the rack shaft 67 by driving the piston 66 provided integrally with the hydraulic pressure supplied from the switching valve 64 to the pair of left and right hydraulic chambers 65A and 65B. The pinion holder 68B is supported by a pinion 68A and a pinion shaft 68C that mesh with 67A, and can swing by a steering torque. Mechanical torque sensor 10 to the pin 64F for the body to provided comprising been spool valve body 64A is engaged, the steering shaft 69 that is coupled to the pinion shaft 68C, comprises a like steering wheel 70.
[0059]
Further, the hydraulic power steering device 40 includes an operating oil pressure source 72 that generates operating oil pressure, an oil tank 71 that stores exhaust oil, an oil supply passage 73 that supplies the operating oil pressure to the switching valve 64 and the variable throttle valve 62, and an oil tank that supplies the exhaust oil. In addition, an oil supply passage 74 returning to 23, an oil supply passage 74A, and connection passages 74B, 76, 77 are provided.
[0060]
The actuator control means 41 includes the target signal setting means 21, the switching means 24, and the drive control means 26 described with reference to the motor drive means 12 in FIG. 2, and is steered for power assistance by pressure oil from the mechanical steering torque sensor 10. The pressure oil applied to the hydraulic reaction chamber 63 for changing the torque is supplied to the vehicle speed signal V from the vehicle speed sensor 11._DThe target current signal I set in advance in the target signal characteristic data generating means (A) 22 and the target signal characteristic data generating means (B) 23 based on_MAAnd target current signal I_MBAnd the switching means 24 is switched based on the shift position signal P from the shift position detection means, so that the target current shown in the characteristic diagram of FIG. 6 corresponding to the steering torque T, the vehicle speed V, and the vehicle state of the shift position P is shown. Signal I_MAEquivalent hydraulic characteristics or target current signal I_MBIt is possible to select a hydraulic characteristic equivalent to.
[0061]
Subsequently, a schematic operation of the hydraulic power steering apparatus 40 will be described.
When the driver operates the steering wheel 70, the steering torque is transmitted to the pinion shaft 68C via the steering shaft 69, the pinion 68A rotates, the rack 67A fitted to the pinion 68A moves, and the rack shaft 67 moves to the steering torque. A manual steering system is configured to perform a linear motion corresponding to the steering direction and move the steered wheels connected via both ends of the rack shaft 67.
[0062]
On the other hand, when the pinion 68A rotates, the pinion holder 68B also rotates, and the spool valve body 64A of the switching valve 64 connected to the pin 64F provided on the pinion holder 68B also moves in the left-right direction in the drawing.
[0063]
For example, when the spool valve body 64A moves in the right direction, the oil supply port 64E that communicates with the oil supply passage 74A is connected to the port 64C that communicates with the hydraulic chamber 65A of the power cylinder 65, and supplies a predetermined oil pressure to the hydraulic chamber 65A.
On the other hand, the oil discharge port 64B communicating with the oil discharge passage 75 is connected to the port 64B communicating with the hydraulic chamber 65B of the power cylinder 65, and the hydraulic pressure in the hydraulic chamber 65B decreases.
[0064]
In this state, the predetermined hydraulic pressure is supplied to the hydraulic chamber 65A, and the hydraulic pressure in the hydraulic chamber 65B decreases. Therefore, the piston 66 of the power cylinder 65 moves to the right in the figure, and the rack shaft 67 also moves to the right. In addition to the manual steering force of the manual steering system, the steering assist force of the hydraulic power steering system is energized.
[0065]
Similarly, when the spool valve body 64A moves in the left direction, a predetermined hydraulic pressure is supplied to the hydraulic chamber 65B and the hydraulic pressure in the hydraulic chamber 65A decreases, so that the piston 66 of the power cylinder 65 moves in the left direction in the figure.
When the driver does not operate the steering wheel 70, the hydraulic pressures in the hydraulic chamber 65A and the hydraulic chamber 65B are equal, and the rack shaft 67 is kept in the neutral position.
[0066]
The steering assist force of the hydraulic power steering system energized by the hydraulic seesaw operation supplied to and discharged from the hydraulic chamber 65A or the hydraulic chamber 65B is generated by a simple hydraulic supply or hydraulic discharge on / off control. The maximum value of the specified range.
[0067]
In order to make the maximum steering assisting force a steering assisting force corresponding to the vehicle state of the steering torque T, the vehicle speed V, and the shift position P, the solenoid current I for driving the solenoid driving means 61 by applying the present invention._SLIs controlled by the vehicle speed V and the shift position P, and the opening of the variable throttle 62C of the variable throttle valve 62 is adjusted to divide the hydraulic pressure supplied from the oil supply path 73 into the oil supply path 74A and the connection path 74B.
[0068]
When the driver operates the steering wheel 70, the steering torque sensor 10 disposed on the steering shaft 69 detects the manual steering torque T, and operates the spool valve body 64A via the pinion holder 68B and the pin 64F to operate the power cylinder 65. Supply pressure oil to
The vehicle speed signal V detected by the vehicle speed sensor 11 and the shift position detecting means 15 and converted into a digital signal corresponding to the state of the vehicle._DThe shift position signal P is supplied to the actuator control means 41.
[0069]
Actuator control means 41 receives vehicle speed signal V_DAnd the target current signal I shown in the characteristic diagram of FIG._MAEquivalent hydraulic characteristics or target current signal I_MBThe actuator driving means 42 is controlled based on the control signal so that the hydraulic characteristic equivalent to the solenoid current I can be selected._SLAnd the solenoid driving means 61 is driven.
[0070]
Solenoid current I_SLIs the shift position position of the automatic / sport driving pattern or the automatic / normal driving pattern, vehicle speed V (VL: low vehicle speed range, V_M: Medium vehicle speed range, V_HIs set to have the same characteristics as the target current signal corresponding to the high vehicle speed range).
[0071]
Solenoid 61A of solenoid driving means 61 is solenoid current I_SLWhen driven by solenoid current I_SLIs applied to the movable core 61B, and the movable core 61B moves to move the spool valve body 62A of the variable throttle valve 62.
[0072]
The variable throttle valve 62 includes an inlet port communicating with the communication path 74B, an outlet port connected to the hydraulic reaction chamber 63, a spool valve body 62A, and a spring that pushes back the spool valve body 62A. The spool valve body 62A has an inlet port and an outlet port. The notch is provided on the inlet port side of the annular groove 62B, and the variable throttle 62C is formed by the inlet port side and the notch.
[0073]
The spool valve element 62A has a solenoid current I_SLIs 0, the annular groove 62B is in a position where the inlet port and the outlet port are completely communicated by the spring force, and the hydraulic pressure (maximum value) supplied from the oil supply passage 74A via the communication passage 74B is supplied to the hydraulic reaction chamber 63. To supply.
[0074]
On the other hand, solenoid current I_SLAs the valve force increases from 0, the spool valve body 62A moves to the left in the figure while balancing with the spring force, the variable throttle 62C adjusts the opening of the inlet port, and the hydraulic reaction chamber 63 via the communication path 74B. The hydraulic pressure supplied to the solenoid is the solenoid current I_SLIt decreases gradually in inverse proportion to and finally becomes zero.
[0075]
The hydraulic reaction chamber 63 is disposed between a pair of opposed plungers (not shown) that are engaged with the spool valve body 64A of the switching valve 64 and are movable in parallel directions. Is provided with a spring (not shown) that urges the valves toward the sides away from each other, so that the spool valve body 64A is applied with a force corresponding to the hydraulic pressure supplied from the outlet port of the variable throttle valve 62 via the connecting passage 76. To the neutral position.
[0076]
Thus, the solenoid current I_SLThus, the solenoid driving means 61 is driven to adjust the opening of the variable throttle 62C of the variable throttle valve 62, the hydraulic pressure supplied to the hydraulic reaction chamber 63 is controlled to brake the spool 64A of the switching valve 64, and the oil supply path The hydraulic pressure supplied to the oil supply port 64E of the switching valve 64 via 74A is the solenoid current I_SLSo that the solenoid current I_SLBy driving the piston 66 of the power cylinder 65 with a hydraulic pressure proportional to the pressure and moving the rack shaft 67, the solenoid current I_SLA steering assisting force corresponding to the above can be applied to the steering system.
[0077]
When the steering rotation speed sensor 9 for detecting the steering rotation speed N of the steering wheel 70 is arranged on the steering shaft 69, the target signal setting means 31 and the target current signal calculation means ( A) 34, target current signal calculation means (B) 37, switching means 24, and drive control means 26 are provided in the actuator control means 41, so that the target current signal I in FIG._MAAnd the control current signal I in FIG._DATarget current signal I_MSAOr the target current signal I in FIG._MBAnd the control current signal I in FIG._DBTarget current signal I_MSBSolenoid current I corresponding to_SLAnd the solenoid current I_SLA corresponding steering assist force can be applied to the steering system.
[0078]
Further, the target current signal I of the manual / sport running pattern shown in FIGS._MAOr target current signal I for manual / normal driving pattern_MBSolenoid current I corresponding to_SLThe solenoid current I_SLA corresponding steering assist force can be applied to the steering system.
[0079]
【The invention's effect】
As explained above,The present inventionThe control means of the power steering device according to the invention changes the characteristics of the control signal based on the signal from the shift position detection means for detecting the shift position of the automatic transmission provided in the vehicle, and corresponds to the same steering torque and the same vehicle speed. Since a plurality of different steering characteristics can be obtained, a steering feeling suitable for the traveling mode of the vehicle can be obtained.
[0080]
Also,The present inventionIn the power steering apparatus according to the present invention, the automatic transmission can be switched from the predetermined shift position in the automatic mode to the manual mode. When the automatic transmission is switched to the manual mode, the control means is configured to output a plurality of targets based on the signal from the shift position detection means. Since the characteristic data value smaller than the characteristic data value corresponding to the automatic mode is selected from the signal characteristic data, it is possible to obtain a steering feeling that is more responsive to the shift characteristics during sports running.
[0081]
Therefore, it is possible to provide a power steering device with excellent operability that automatically links the steering characteristics to the speed change characteristics and provides a reliable steering feeling according to the driver's preference.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an electric power steering apparatus according to the present invention.
[Figure 2]This inventionThe principal block block diagram of the electric power steering device which concerns on
3 is a block diagram of the main part of one embodiment of the target signal setting means of FIG. 2;
FIG. 4 is a block diagram of the main part of another embodiment of the motor control means according to the present invention.
FIG. 5 is an overall configuration diagram of a hydraulic power steering apparatus according to the present invention.
FIG. 6: Vehicle speed signal V in automatic mode_D(V_L, V_M, V_H) As a parameter for steering torque signal T_D-Target current signal I_MSCharacteristics chart
[Fig. 7] Vehicle speed signal V_DSteering rotational speed signal N_D-Braking current signal (I_DA, I_DB) Characteristics
FIG. 8: Vehicle speed signal V in manual mode_D(V_L, V_M, V_H) As a parameter for steering torque signal T_D-Target current signal I_MSCharacteristics chart
FIG. 9 is a layout diagram of an automatic transmission.
Fig. 10 Image of shift position display
FIG. 11 is a block diagram of the shift position detecting means.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electric power steering device, 2 ... Steering wheel, 3 ... Steering shaft, 4 ... Hypoid gear, 5 ... Rack & pinion mechanism, 5a ... Pinion, 5b ... Rack shaft, 6 ... Tie rod, 7 ... Front wheel, 8 ... Electric motor, 9 DESCRIPTION OF SYMBOLS ... Steering rotational speed sensor, 10 ... Steering torque sensor, 11 ... Vehicle speed sensor, 12, 30 ... Electric motor control means, 13 ... Electric motor drive means, 14 ... Electric motor current detection means, 15 ... Shift position detection means, 21, 31 ... Target Signal setting means 22, 32 ... Target signal characteristic data generating means (A), 22A ... Sport running pattern data storage means, 22B, 23B ... Data access means, 23, 35 ... Target signal characteristic data generating means (B), 23A ... normal running pattern data storage means, 24 ... switching means, 25 ... deviation calculating means, 26 ... drive control means, 33 ... braking signal characteristic data generating means (A), 34 ... target current signal calculating means (A), 36 ... braking signal characteristic data generating means (B) 37 ... target current signal calculating means (B) 40 ... hydraulic power steering device, 41 ... actuator control means, 42 ... actuator drive means, 61 ... solenoid drive means, 62 ... variable throttle valve, 63 ... hydraulic reaction chamber, 64 ... switching valve, 65 ... power cylinder, I_M... Motor current, I_MD... Motor current detection signal, I_MA, I_MB, I_MS, I_MSA, I_MSB... Target current signal, I_DA, I_DB... Brake current signal, ΔI ... Deviation signal, I_SL... Solenoid current, P, P_S, P_T... Shift position signal, T, T_D... Steering torque signal, V, V_D... Vehicle speed signal, V_O... Motor control signal, V_M... motor voltage.

Claims (2)

A steering torque sensor for detecting a steering torque applied to the steering system of the vehicle, an actuator for giving an auxiliary torque to the steering system, a steering torque signal detected by the steering torque sensor, or a plurality of sensor signals including the steering torque. A power steering device comprising: control means for outputting a control signal for controlling the driving of the actuator based on the driving means; and driving means for driving the actuator based on the control signal;
The control means changes the characteristic of the control signal based on a signal from a shift position detection means for detecting a shift position of an automatic transmission provided in the vehicle,
The automatic transmission device can be switched from a predetermined shift position in the automatic mode to the manual mode. A power steering device , wherein a characteristic data value smaller than a characteristic data value corresponding to the automatic mode is selected . Selecting a characteristic data value smaller than a characteristic data value corresponding to the automatic mode from the plurality of target signal characteristic data at the time of at least one shift position other than the low gear and the top gear among the shift positions in the manual mode. The power steering apparatus according to claim 1, wherein the power steering apparatus is a power steering apparatus.

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