JP2001260917A - Power steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress driving torque of a pump to save control energy by bringing a control flow rate QP controlled with a flow control valve V close to a flow rate required by the output side of a power cylinder 8 or a steering valve 9, and to enhance responsiveness within the limit of safety when steering is quickly operated even in high speed traveling. SOLUTION: Exciting current I of a solenoid is decided based on a steering angle θ in high speed traveling. The exciting current I of the solenoid is decided based on steering angle speed ω in low speed traveling. When steering is quickly operated in the high speed traveling, the responsiveness is enhanced within the limit of a steering angle speed current instruction value 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power steering apparatus provided with a flow control valve for controlling a flow guided to a power cylinder.

[0002]

2. Description of the Related Art A flow control valve incorporated in a power steering apparatus of this type incorporates a spool in a main body, and has one end of the spool facing one pilot chamber which is always in communication with a pump port, and the other end of the spool. Is exposed to one pilot room with a spring interposed. A fixed orifice is provided downstream of the one pilot chamber, and pressure oil is guided to a steering valve for controlling a power cylinder via the fixed orifice.

On the other hand, the pressure on the upstream side of the orifice is used as the pilot pressure in the one pilot chamber, and the pressure on the downstream side is used as the pilot pressure in the other pilot chamber. I try to control. According to the movement position of the spool, the discharge amount of the pump is distributed to a control flow rate QP for guiding the discharge amount to the steering valve side and a return flow rate QT for recirculation to the tank or the pump. And the spool keeps the differential pressure before and after the fixed orifice constant,
On the steering valve side that controls the power cylinder,
A constant control flow rate QP is always supplied.

[0004]

In the conventional apparatus as described above, a constant control flow QP is always supplied from the flow control valve.
Is supplied to the steering valve side that controls the power cylinder. In other words, the control flow rate Q
P continuously supplies a constant control flow rate QP to the steering valve side regardless of the vehicle speed or the steering condition. However, regardless of vehicle speed or steering conditions,
When the control flow rate QP is specified, for example, when QP> QM with respect to the flow rate QM required by the power cylinder, the surplus flow rate must be returned to the tank via the steering valve.

[0005] Returning the surplus flow rate to the tank via the steering valve as described above increases the pressure loss of the circuit accordingly. In other words, the pump must continue to consume the drive torque corresponding to the pressure loss. Therefore, the larger the driving torque of the pump, the more energy is consumed.

Further, since the control flow rate QP is set in accordance with the maximum required flow rate of the power cylinder, in most cases, at present, some surplus flow rate is returned to the tank. Therefore, in this conventional device,
There is a problem that the energy loss becomes large.
An object of the present invention is to provide a power steering device that controls the control flow rate QP in accordance with running conditions and steering conditions of a vehicle to minimize energy loss.

[0007]

The present invention is based on the following configuration. A spool is incorporated in the main body, and one end of the spool faces one pilot chamber which is always in communication with the pump port, and the other end of the spool faces the other pilot chamber via a spring. An orifice is provided downstream of the one pilot chamber, and pressure oil is guided to a steering valve for controlling a power cylinder via the orifice. On the other hand, the pressure on the upstream side of the orifice is used as the pilot pressure in the one pilot chamber, and the pressure on the downstream side is used as the pilot pressure in the other pilot chamber. Then, in accordance with the position of the spool, the discharge amount of the pump is divided into a control flow QP for guiding the steering valve to the steering valve and a return flow QT for returning to the tank or the pump.

In the first invention, the orifice is a variable orifice whose opening is controlled according to the exciting current I of the solenoid, and the exciting current I of the solenoid of the variable orifice is controlled while assuming the above-mentioned device. A steering angle sensor is connected to the controller, and the controller calculates or stores a steering angle θ and a steering angular velocity ω according to the steering angle from the steering angle sensor. The solenoid current command value I1 corresponding to the steering angle θ and the solenoid current command value I2 corresponding to the steering angular velocity ω are stored or calculated, and the solenoid current command value I1 corresponding to the steering angle θ and the steering angle current command value corresponding to the vehicle speed are stored. The current command value I2 according to the steering angular velocity ω is the limit value of the current command value I4 for the steering angular velocity based on the vehicle speed signal. Moreover, the magnitude of the integrated value of the solenoid current command values I1 and I3 and the solenoid current I2 whose limit value is the solenoid current command value I4 are determined, and the solenoid of the variable orifice is determined based on the larger value. It is characterized in that the exciting current I is controlled.

In the second invention, the larger current command value is
The feature is that the solenoid current command value I7 for standby is added.

In the first invention, since the steering angle current command value I3 and the steering angular velocity current command value I4 are separated, the gain and the like of the two command values I3 and I4 are determined. Can be set to any value.

For example, the steering angle current value I3 has a maximum value of 1 and a minimum value of 0.6, while the steering angle velocity current value I4 has a maximum value of 1 and a minimum value of 0.8. By thus making the maximum value and the minimum value, particularly the minimum value, different, it is possible to change the graph-like inclination of the steering angle current value I3 and the steering angular velocity current value I4.
By making this slope, that is, the gain different,
It is possible to maintain the vehicle's followability and responsiveness to the steering operation in an optimum state.

Further, according to the second aspect of the present invention, since the standby flow rate is secured, it is possible to prevent burn-in of the apparatus and to cope with disturbance such as kickback. Further, good responsiveness can be ensured.

[0013]

1 and 2 show one embodiment. Therefore, first, based on FIG.
The configuration of the entire power steering device will be described. Body B
, The pump P is integrally incorporated with the spool 1 of the flow control valve V. The spool 1 has one end facing one pilot chamber 2 and the other end facing the other pilot chamber 3. The one pilot room 2 is
It is always in communication with the pump P via the pump port 4.
A spring 5 is interposed in the other pilot chamber 3. The two pilot chambers 2 and 3 thus communicate with each other via a variable orifice a that controls the opening in accordance with the exciting current I of the solenoid SOL.

That is, one pilot chamber 2 communicates with the inflow side of the steering valve 9 for controlling the power cylinder 8 via the flow path 6 → the variable orifice a → the flow path 7. The other pilot chamber 3 communicates with the inflow side of the steering valve 9 via the flow path 10 and the flow path 7. Therefore, the two pilot chambers 2 and 3 are
The communication is performed via the variable orifice a, and the pressure on the upstream side of the variable orifice a acts on one pilot chamber, and the pressure on the downstream side acts on the other pilot chamber 3.

The spool 1 maintains a position where the acting force of one pilot chamber 2 and the acting force of the other pilot chamber 3 are balanced.
The opening between the pump port 4 and the tank port 11 is determined. If the pump drive source 12 including the engine or the like is stopped, no pressure oil is supplied to the pump port 4.
If pressure oil is not supplied to the pump port 4, no pressure is generated in both pilot chambers 2, 3, so that the spool 1 maintains the normal position shown by the action of the spring 5.

When the pump P is driven from the above-mentioned state and the pressure oil is supplied to the pump port 4, a flow is generated in the variable orifice a, so that a pressure loss occurs there. Due to the effect of the pressure loss, a pressure difference is generated between the pilot chambers 2 and 3, and the spool 1 moves against the spring 5 in accordance with the pressure difference to maintain the above-mentioned balance position. By moving the spool 1 against the spring 5 in this manner,
Although the opening of the tank port 11 is increased, the steering valve 9 is adjusted according to the opening of the tank port 11 at this time.
The distribution ratio of the control flow QP guided to the side and the return flow QT returned to the tank T or the pump P is determined. In other words, the control flow rate QP depends on the opening of the tank port 11.
Will be determined.

As described above, the control flow rate QP
Is controlled in accordance with the opening degree of the tank port 11 determined by the moving position of the variable orifice, the control flow rate QP is ultimately determined in accordance with the opening degree of the variable orifice a. This is because the moving position of the spool 1 is determined by the pressure difference between the pilot chambers 2 and 3, and the difference in pressure is determined by the opening of the variable orifice a.

Therefore, in order to control the control flow rate QP according to the vehicle speed and the steering condition, the opening of the variable orifice a, that is, the exciting current of the solenoid SOL may be controlled. This is because the opening of the variable orifice a is kept to a minimum when the solenoid SOL is in a non-excited state, and the opening is increased as the exciting current is increased.

The steering valve 9 controls the flow rate supplied to the power cylinder 8 in accordance with the input torque (steering torque) of a steering wheel (not shown). For example, if the steering torque is large, the supply amount to the power cylinder 8 is increased, and if the steering torque is small, the supply flow rate is reduced accordingly. The steering torque and the switching amount of the steering valve 9 are determined by a torsional reaction force of a not-shown torsion bar or the like.

When the steering torque is large as described above,
When the switching amount of the steering valve 9 is increased, the assisting force of the power cylinder 8 is correspondingly increased. Conversely, if the switching amount of the steering valve 9 is reduced, the assist force is reduced. The necessity (requirement) of the power cylinder 8 determined by the steering torque
If the flow rate QM and the control flow rate QP determined by the flow control valve V are always equal, the energy loss on the pump P side can be suppressed low. This is because the energy loss on the pump P side occurs due to the difference between the control flow rate QP and the required amount QM of the power cylinder 8.

As described above, in order to make the control flow rate QP as close as possible to the required quantity QM of the power cylinder 8, the opening of the variable orifice a is controlled by the solenoid SOL.
The controller C controls the exciting current. In this controller C,
The steering angle sensor 16 and the vehicle speed sensor 17 are connected, and based on the output signals of both sensors, the solenoid SO
The exciting current of L is controlled.

In the figure, reference numeral 18 denotes a slit formed at the tip of the spool 1. When the spool 1 is at the position shown in FIG. They are always in communication. In other words, even when the spool 1 is in the illustrated state and the flow path 6 is closed, the discharge oil of the pump P is supplied to the steering valve 9 side through the slit 18. ing. Although the flow rate is very small as described above, the purpose of supplying the pressure oil to the steering valve 9 is to prevent seizure of the entire apparatus, prevent disturbance such as kickback, and ensure responsiveness. Because. However, these objectives can also be achieved by securing a standby flow rate described later, and thus a detailed description will be given later.

Reference numeral 19 denotes a driver connected between the controller C and the solenoid SOL.

The control system of the controller C is as shown in FIG. That is, the steering angle signal from the steering angle sensor 16 and the vehicle speed signal from the vehicle speed sensor 17 are input to the controller C. Then, the controller C calculates the steering angle θ and the steering angular velocity ω from the steering angle signal. Then, the steering angle θ and the steering angular velocity ω
The required amount QM is estimated on the basis of the steering flow, but actually, the required flow rate QM is estimated based on the steering torque.
Specifying M allows for more accurate control. However, if an attempt is made to control the opening of the variable orifice a by detecting the steering torque, the current power steering system must be drastically changed.

However, if the required flow rate QM is estimated based on the steering angle θ and the steering angular velocity ω as in this embodiment, the current power steering system itself can be hardly changed. . Therefore, although it leads to the features of the present invention, it is a feature that detecting the steering angle θ and the steering angular velocity ω and estimating the required flow rate QM can greatly reduce the cost compared to a system that directly detects the steering torque. is there.

For the above reasons, the controller C controls the exciting current of the solenoid SOL based on the steering angle θ and the steering angular velocity ω. The control form is shown in FIG.
As shown in FIG. The steering angle θ and the solenoid current command value I1 in FIG. 2 are determined based on a theoretical value in which the relationship between the steering angle θ and the control flow rate QP has a linear characteristic. The relationship between the steering angular velocity ω and the solenoid current command value I2 is also determined based on the theoretical value at which the steering angular velocity ω and the control flow rate QP have linear characteristics.

However, when the steering angle θ and the steering angular velocity ω are
If the value does not exceed a certain set value, both the command values I1 and I2 output zero. That is, when the steering wheel is at or near neutral, both the command values I1 and I2 are set to zero. The solenoid current command value I1 for the steering angle θ and the solenoid current command value I2 for the steering angular velocity ω may be stored in the controller C in advance as table values, or may be based on the steering angle θ or the steering angular velocity ω. Then, the controller C may be made to calculate each time.

The controller C has a vehicle speed sensor 1
7, a steering angle current command value I3 and a steering angular speed current command value I4 are output. These steering angle current command value I3 and steering angular speed current command value I4 are May be stored in the controller C in advance as a table value, or the controller C may calculate each time based on the vehicle speed V.

The steering angle current command value I3 is set to 1 in the low speed range and is output, for example, 0.6 in the highest speed range. Further, the steering angular velocity current command value I4 is designed to output 1 in the low speed range and output, for example, 0.8 in the highest speed range. That is, the steering angle current command value I3 is 1
, While the steering angular velocity current command value I4 is controlled in the range of 1 to 0.8.
Accordingly, the gain from the low speed range to the highest speed range is set so that the steering angle current command value I3 is larger.

Then, the solenoid current command value I1 based on the steering angle θ is multiplied by a steering angle current command value I3 corresponding to the vehicle speed V. Therefore, the higher the vehicle speed V, the smaller the output value as a result of the integration, that is, the current command value I5 of the steering angle system. In addition, since the gain of the steering angle current command value I3 is made larger than the gain of the steering angular velocity current command value I4, the higher the speed is, the larger the decrease rate becomes.

On the other hand, as the solenoid current command value I2 based on the steering angular velocity ω, a current command value I6 for the steering angular velocity system is output with the steering angular velocity current command value I4 corresponding to the vehicle speed as a limit value. The current command value I6 is also reduced according to the vehicle speed.
Since the gain is smaller than the gain of the steering angular velocity current command value I4, the reduction rate of the current command value I6 is smaller than that of the current command value I5.

The current command value I5 of the steering angle system output as described above is compared with the current command value I6 of the steering angular velocity system, and the larger I5 or I6 is adopted. The reason for adopting the larger one is as follows. That is, when the vehicle is running at high speed, it is unlikely that the steering will be suddenly operated, so that the current command value I6 of the steering angular velocity system is generally small and the current command value I5 of the steering angle system is generally large.

Therefore, at the time of high-speed running, the gain of the current command value I5 of the steering angle system is increased with reference to the steering angle in order to enhance the safety and stability of the steering operation. In other words, the higher the traveling speed is, the higher the ratio of decreasing the control flow rate QP is, so as to reduce the energy loss.

On the other hand, when the vehicle is traveling at low speed, the steering is frequently operated suddenly. Therefore, in many cases, the steering angular velocity becomes larger. When the steering angular velocity is high as described above, responsiveness is emphasized. Therefore, at the time of low-speed running, the gain of the current command value I6 of the steering angular velocity system is reduced with reference to the steering angular velocity in order to enhance the operability, that is, the responsiveness of the steering operation. In other words, even if the running speed increases to some extent,
When the steering is suddenly operated, the control flow rate QP is sufficiently ensured to give priority to the responsiveness.

However, even when the traveling speed of the vehicle is constant, the current command value I5 of the steering angle system increases or the current command value I6 of the steering angular speed system increases. For example, when the steering wheel is steered by a certain angle, and at the position of the steering angle θ,
When the steering is stopped and the steering is maintained, the steering angular velocity ω becomes zero. Therefore, even if the vehicle speed is the same, the current command value I6 of the steering angular velocity system is initially large, and the current command value I5 of the steering angular system becomes larger after the steering is started. In any case, since the larger one of the current command values I5 and I6 is selected, any current command value is output under any traveling condition.

If the current command values I5 and I6 are not output during the above-mentioned steering hold, the control flow rate QP
Can not be secured. If the control flow rate QP cannot be ensured, the power cylinder 8 will move at the time of steering maintenance, losing the drag due to the self-aligning torque of the vehicle. If the power cylinder 8 moves without maintaining its position in this way, it becomes impossible to maintain the steering itself.

However, as described above, either one of the current command values I5 and I6 is used, so that both will not become zero during the steering operation. In other words, the steering angle θ is maintained even during steering, so that the solenoid current command value I1 can be secured. Therefore, the power required for steering maintenance can be maintained at the current command value I1.

On the other hand, the steering wheel may be operated suddenly even during high-speed running. At this time, the current command value I6 of the steering angular velocity system increases, so that current command value I6 is selected. However, since the current command value I6 is a value controlled within the range of the limit value of the steering angular velocity current command value I4, safety is sufficiently ensured. However, the minimum limit value of the steering angular velocity current command value I4 when the vehicle is running at high speed is slightly larger than the minimum value of the steering angle current command value I3. That is, in this embodiment, as described above, the minimum value of the steering angle current command value I3 is set to 0.6, and the limit minimum value of the steering angular velocity current command value I4 is set to 0.8.

Therefore, when the vehicle is controlled at a high speed, the response is better when controlled by the current command value I6 of the steering angular velocity system than when controlled by the current command value I5 of the steering angle system. However, if the responsiveness is made too high during high-speed running, there is a risk that safety will be impaired. Therefore, the limit minimum value of the steering angular velocity current command value I4 is set to 0.8, which is based on safety based on the yaw rate of the vehicle.

That is, when the vehicle is running at a vehicle speed of about 60 km / h or less, the convergence characteristics are almost similar. That is, at 60 km / h or less, the convergence hardly changes regardless of whether the vehicle is traveling at 10 km / h or traveling at 40 km / h. The range in which the convergence of the yaw rate is stable is regarded as the safety limit, and the limit minimum value of the steering angular velocity current command value I4 is set to 0.8.

Therefore, according to this embodiment, 10
When the vehicle is running at 0 km / h, the steering is suddenly operated, and when the current command value I6 of the steering angular velocity system is increased and the current command value I6 is selected, the same as when traveling at 60 km / h. Steering can be performed with a high level of safety and stability.

The current command value I5 or I6 selected as described above includes the standby current command value I7.
Is added. This standby current command I7 is always
A predetermined current is supplied to the solenoid SOL of the variable orifice a. The variable orifice a supplied with the standby current command value I7 in this manner.
Keeps the opening constant and maintains a constant standby flow rate even if the solenoid current command value based on the steering angle θ, the steering angular velocity ω, and the vehicle speed is zero.

However, from the viewpoint of energy saving, if the required flow rate QM of the power cylinder 8 and the steering valve 9 is zero, it is ideal that the control flow rate QP of the flow control valve V is also zero. It is as follows. Making the control flow rate QP zero means that the pump P
Means that the entire discharge amount is returned from the tank port 11 to the pump P or the tank T. The flow path returning from the tank port 11 to the pump P or the tank T is very short in the main body B, so that there is almost no pressure loss. Since there is almost no pressure loss, the pump P
Drive torque is also minimized, which leads to energy savings. In this sense, it is absolutely advantageous to make the control flow rate QP zero when the required flow rate QM is zero from the viewpoint of energy saving.

Nevertheless, the reason why the standby flow rate QS is ensured even when the required flow rate QM is zero is due to the following three reasons. Prevention of burn-in of the device If a certain amount of oil is circulated through the device, the cooling effect of the oil can be expected, but the standby flow rate fulfills this cooling function.

Resistance to Disturbances such as Kickback and Self-Aligning Torque When drag force due to disturbances and self-aligning torque acts on the tire, it acts on the rod of the power cylinder 8. If you do not secure standby flow,
The tire fluctuates due to the drag caused by the disturbance and the self-aligning torque. However, if the standby flow rate is secured, the tire does not fluctuate even if the above-mentioned drag acts. That is, since a pinion or the like for switching the steering valve 9 is engaged with the rod of the power cylinder 8, when the above-described drag acts, the steering valve is also switched to supply the standby flow in a direction opposing the drag. Will do. Therefore, if the standby flow rate is secured,
It is possible to counter the disturbance due to the kickback and the self-aligning torque.

For example, if the standby flow rate QS is ensured, the time required to reach the target control flow rate QP is shorter than when there is no standby flow rate QS. Since this time difference becomes responsiveness, the responsiveness can be improved by securing the standby flow rate QS after all.

Next, the operation of this embodiment will be described.
Now, while the vehicle is running, a steering angle current command value I5, which is an integrated value of the solenoid current command value I1 based on the steering angle and the steering angle current command value I3, is output. At the same time, a solenoid current command value I2 based on the steering angular velocity is output, and a current command value I6 for the steering angular velocity system is output with the current command value for fast steering angular velocity I4 as a limit value.

Then, the magnitude of the current command value I5 of the steering angle system and the current command value I6 of the steering angular velocity system is determined, and the standby current command value I7 is added to the larger command value I5 or I6. Then, the solenoid exciting current I at that time is determined. This solenoid exciting current I
When the vehicle is traveling at high speed, the current command value I5 of the steering angle system is mainly used as a reference, and when the vehicle is running at low speed, the current command value I6 of the steering angular speed system is mainly used as a reference.

However, according to this embodiment, even when the vehicle is running at a low speed, the excitation current I of the solenoid is determined based on the current command value I5 of the steering angle system when the steering is maintained. Further, even when the vehicle is running at high speed, when the steering is operated suddenly, the exciting current I of the solenoid is determined based on the current command value I6 of the steering angular velocity system. However, in this case, as described above, even when traveling at 100 km / h, the steering operation can be performed with the same safety and stability as when traveling at 60 km / h.

[0050]

According to the first aspect of the present invention, at the time of high-speed running, the excitation current I of the solenoid can be determined based on the steering angle, so that the safety of steering can be ensured.
When the vehicle is running at a low speed, the exciting current I of the solenoid can be determined based on the steering angular velocity, so that steering responsiveness can be ensured. Moreover, even at high speeds,
When the steering wheel is suddenly operated, the responsiveness can be ensured within the range of the limit value based on the vehicle speed, so that the safety is improved in a situation such as obstacle avoidance during high-speed running. In addition, when the steering wheel is stopped and the steering wheel is stopped, the control flow rate QP can be appropriately secured by the steering angle θ to counter the self-aligning torque.

According to the second aspect, even when the steering angle θ and the steering angular velocity ω are zero as in the case of straight running, the standby flow rate can be ensured. Therefore, burn-in of the apparatus can be prevented, and disturbance such as kickback can be dealt with.
Further, good responsiveness can be ensured.

In any of the first and second aspects of the invention, the control flow rate is controlled when the steering wheel is turned off, when the steering wheel is stopped, or when the vehicle is traveling straight. , And the torque for driving the pump is not increased more than necessary, so that accurate energy saving control can be realized.

In the power steering device,
2. Description of the Related Art Conventionally, signals such as a steering angle, a steering angular velocity, and a vehicle speed are used to control a steering reaction force on an output side or to control sensitivity of a steering valve. However, as in the present invention, the control flow rate QP is controlled to save energy, and there is no hitherto known one that uses signals such as a steering angle, a steering angular velocity, and a vehicle speed. The present invention has the greatest feature in that signals such as a steering angle, a steering angular velocity, and a vehicle speed are used with the theme of energy saving.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of a first embodiment.

FIG. 2 is an explanatory diagram illustrating a control system of a controller according to the first embodiment.

[Explanation of symbols]

 I Solenoid current command value I1 Solenoid current command value based on steering angle θ I2 Solenoid current command value based on steering angular velocity ω I3 Steering angle current command value I4 Steering angular velocity current command value QP Control flow QT Return flow QM Required flow (required flow) QS Standby flow rate B Body 1 Spool 2 One pilot room 3 The other pilot room 4 Pump port P Pump SOL Solenoid a Variable orifice 8 Power cylinder 9 Steering valve C Controller 16 Steering angle sensor 17 Vehicle speed sensor T tank

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3D032 CC12 CC49 DA03 DA09 DA23 EC04 3D033 EB07

Claims (2)

[Claims] 1. A spool is incorporated in a main body, and one end of the spool faces one pilot chamber which is always in communication with a pump port, and the other end of the spool faces the other pilot chamber via a spring. An orifice is provided on the downstream side of the one pilot chamber, and pressure oil is guided to a steering valve that controls a power cylinder through the orifice, while the pressure on the upstream side of the orifice is used as the pilot pressure of the one pilot chamber, The downstream pressure is used as the pilot pressure of the other pilot chamber, and the spool movement position is controlled by the pressure balance between the two pilot chambers, and the discharge amount of the pump is guided to the steering valve side according to the movement position. A power source configured to distribute the flow rate QP and the return flow rate QT to be returned to the tank or the pump. In the tearing device, the orifice is a variable orifice that controls the opening in accordance with the exciting current I of the solenoid, and a controller that controls the exciting current I of the solenoid of the variable orifice is provided. An angle sensor is connected, and a steering angle θ and a steering angular velocity ω corresponding to the steering angle from the steering angle sensor are calculated or stored. On the other hand, the controller determines a solenoid current command value I1 and a steering angular velocity While the solenoid current command value I2 corresponding to ω is stored or calculated, the solenoid current command value I1 corresponding to the steering angle θ and the steering angle current command value I3 corresponding to the vehicle speed are integrated, while The above-mentioned current command value I2 is limited to the steering angular speed current command value I4 corresponding to the vehicle speed signal. And the integrated value of the current instruction value I1 and I3, the solenoid current instruction value I
Judge the magnitude of the solenoid current I2 with 4 as the limit value,
A power steering device configured to control the exciting current I of the solenoid of the variable orifice based on the larger value. 2. A power steering apparatus according to claim 1, wherein a standby solenoid current command value I7 is added to the larger current command value.