JP2009137421A - Actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator capable of enhancing the riding comfort in a vehicle even when the actuator is hydraulic type. <P>SOLUTION: The actuator A includes a cylinder C to be interposed between a vehicle body B of a railroad vehicle and a truck W and a hydraulic pump 1 to be driven by a motor M for feeding the hydraulic pressure to the cylinder C, and inclines the vehicle body B with respect to the truck W. The actuator regulates the current limit value ±I<SP>*</SP>for limiting the current to be supplied to the motor M based on the amplitude L of the vibration in the predetermined frequency band out of the vibrations of the vehicle body B or the vibrations of the vehicle body B to the truck W. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of an actuator that is interposed between a vehicle body and a carriage of a railway vehicle and tilts the vehicle body with respect to the carriage.

  When the railway vehicle travels in a curved section, a centrifugal force directed to the side opposite to the curvature center of the curved section acts on the vehicle body. This centrifugal force increases as the traveling speed of the vehicle increases. Therefore, in the railroad track, a height difference called Kant is provided on the inner rail on the opposite side of the center of curvature and the outer rail on the opposite side to alleviate the centrifugal force, thereby improving the speed of the railcar during curve driving. .

  However, the cant amount (the difference in height between the rails) cannot be changed once it is set. In a line area where a railway vehicle with a different traveling speed travels, the higher the railway vehicle travels, the greater the cant amount. There is a problem that the excessive centrifugal force acts on the railway vehicle and the ride comfort deteriorates.

  Therefore, in recent years, a pendulum type vehicle body tilting device or a vehicle body tilting device that tilts the vehicle body with respect to the cart using a gas spring provided between the cart and the vehicle body is mounted. In order to reduce the force, when the railway vehicle travels in a curved section, the body is tilted toward the center of curvature with respect to the carriage to suppress the deterioration of ride comfort, thereby realizing high-speed traveling in the curved section. ing.

In such a vehicle body tilting device, specifically, for example, a direct acting actuator driven by air pressure is interposed between the vehicle body and the carriage, and the actuator is extended and contracted to make the vehicle body a carriage. It is made to incline with respect to (for example, refer patent document 1).
JP 2002-154432 A

  However, since the actuator is driven by using compressed air having a large compressibility, the thrust and the response are insufficient, and it is difficult to secure the target vehicle body inclination angle, and the riding comfort is sufficiently improved. In order to solve this problem, it is conceivable to employ an actuator that is driven not by air pressure but by hydraulic pressure.

  However, when the working fluid of the actuator is a liquid, the apparent rigidity of the actuator is increased due to the low compressibility of the liquid, and the vehicle body travels in the carriage via the actuator that is used for tilting the vehicle body. There is a risk that the vibration in the left-right direction with respect to the direction is transmitted to the vehicle body and the riding comfort of the vehicle is deteriorated. The apparent rigidity of the actuator is the rigidity in the expansion and contraction direction of the entire actuator including the working fluid, and the above-mentioned apparent rigidity tends to increase as the compressibility of the working fluid decreases. Become.

  Therefore, the present invention was devised in order to improve the above-described problems, and an object of the present invention is to provide an actuator that can improve riding comfort in a vehicle even if it is hydraulic. is there.

In order to achieve the above-described object, an actuator in the problem solving means of the present invention includes a cylinder interposed between a vehicle body and a carriage of a railway vehicle, and a hydraulic pump driven by a motor that supplies hydraulic pressure to the cylinder. An actuator for tilting the vehicle body relative to the carriage, and limiting a current amount supplied to the motor based on an amplitude of vibration in a predetermined frequency band of vibration of the vehicle body or vibration of the vehicle body relative to the carriage Suppose you want to adjust the value.

  According to the actuator of the present invention, the limit value for limiting the amount of current supplied to the motor is adjusted based on the amplitude of vibration in a predetermined frequency band, so that vibration in the frequency band that deteriorates riding comfort due to disturbance acts on the carriage. Even so, it is possible to suppress the vibration input to the carriage side from propagating to the vehicle body side, and the ride comfort in the vehicle can be improved even if a hydraulic actuator is used for vehicle body tilting.

  In other words, the ride comfort in the vehicle can be improved, so that the working fluid of the actuator can be liquid working oil, the lack of propulsive force can be eliminated, and the response of the vehicle body tilt can be improved. It can be done.

The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a diagram illustrating a hydraulic circuit of an actuator according to an embodiment. FIG. 2 is a diagram illustrating a state in which the actuator according to the embodiment is interposed between the vehicle body and the carriage of the railway vehicle. FIG. 3 is a control block diagram of the actuator according to the embodiment. FIG. 4 is a diagram showing the relationship between the amplitude of a vibration component in a predetermined frequency band in the displacement signal and a coefficient for weighting the amplitude. FIG. 5 is a diagram illustrating an example of a flowchart for controlling the current limit value in the control unit that controls the motor of the actuator according to the embodiment. FIG. 6 is a control block diagram of an actuator in a modification of the embodiment.

  As shown in FIGS. 1 and 2, the actuator A in one embodiment includes a cylinder C interposed between a vehicle body B and a carriage W of a railway vehicle, and a motor M that supplies hydraulic pressure to the cylinder C. The hydraulic pump 1 to be driven and a controller 20 that controls the motor M are provided.

  In this actuator A, the cylinder C can be driven by the hydraulic pressure supplied from the hydraulic pump 1, and in this embodiment, specifically, the cylinder C is driven by the hydraulic pressure. Therefore, an actuator circuit 5 is provided.

  Hereinafter, each part will be described in detail. The cylinder C includes a container 2 and a piston 3 that is slidably inserted into the container 2 and divides the two pressure chambers of the one chamber R1 and the other chamber R2 into the container 2. The rod 4 is connected to the piston 3 and is movably inserted into the container 2, and the one chamber R1 and the other chamber R2 are filled with hydraulic oil as a liquid. In this case, a so-called double rod type hydraulic cylinder is used. In the present embodiment, the liquid used for the operation of the cylinder C is hydraulic oil, but the liquid only needs to be suitable for the operation of the actuator A.

  The hydraulic pump 1 is incorporated in an actuator circuit 5 that operates the cylinder C as an actuator. The actuator circuit 5 includes a loop passage 6, two solenoid switching valves 7 and 8 provided in the loop passage 6, and a loop. Two branch passages 9 and 10 branching from the passage 6 and a low pressure selection valve 12 communicating the low pressure side of the branch passages 9 and 10 with the accumulator 11 are provided.

  Specifically, the hydraulic pump 1 is provided in the middle of a loop passage 6 that connects the one chamber R1 and the other chamber R2 of the cylinder C. In this case, the hydraulic pump 1 is configured as a bidirectional discharge pump that is driven by the motor M. ing. Note that leakage hydraulic pressure generated in the hydraulic pump 1 is recovered by the accumulator 11.

  A normally closed solenoid switching valve 7 is interposed in the middle of the loop passage 6 between the hydraulic pump 1 and the one chamber R1, and further between the hydraulic pump 1 and the other chamber R2. A normally closed solenoid switching valve 8 is interposed.

  The solenoid switching valve 7 adopts a shut-off position with a valve 7a having a communication position for communicating the hydraulic pump 1 and the one chamber R1, and a shut-off position allowing only the flow from the hydraulic pump 1 to the one chamber R1. Are provided with a spring 7b for energizing the valve 7a and a solenoid 7c for switching the valve 7a to the communication position opposite to the spring 7b when energized. The other solenoid switching valve 8 is composed of the hydraulic pump 1 and the other chamber R2. A valve 8a having a communication position that allows communication between the hydraulic pump 1 and the shut-off position that allows only the flow from the hydraulic pump 1 to the other chamber R2, a spring 8b that biases the valve 8a so as to take the shut-off position, A solenoid 8c that switches the valve 8a to the communication position so as to face the spring 8b is provided.

  Further, the branch passage 9 is branched from the solenoid switching valve 7 and the hydraulic pump 1 in the middle of the loop passage 6, and the other branch passage 10 is in the middle of the loop passage 6 and the solenoid switching valve 8. It branches from between the hydraulic pump 1 and the low pressure side of these branch passages 9 and 10 is communicated to the accumulator 11 by the low pressure selection valve 12.

  The low-pressure selection valve 12 has one side communication position for communicating the branch flow path 9 to the accumulator 11, the other side communication position for communicating the branch flow path 10 to the accumulator 11, and both the branch flow paths 9 and 10 to the accumulator 11. A valve 12a having a both-side communication position that communicates, a pilot passage 12b that applies the pressure of the branch passage 9 so as to switch the valve 12a to the other-side communication position, and a branch that switches the valve 12a to the one-side communication position A pilot passage 12c that applies the pressure of the flow path 10 and is configured to take a two-way communication position in the neutral position.

  Therefore, when the pressure on the branch flow path 9 side exceeds the pressure on the branch flow path 10 side, the low pressure selection valve 12 takes the other side communication position and communicates the branch flow path 10 with the accumulator 11. When the pressure on the path 10 side exceeds the pressure on the branch flow path 9 side, the low pressure selection valve 12 takes the one-side communication position and connects the branch flow path 9 to the accumulator 11.

  That is, when the solenoid switching valves 7 and 8 are respectively set to the communication positions and the hydraulic pump 1 is driven to supply hydraulic pressure to the one chamber R1, the hydraulic pressure is supplied into the one chamber R1 and the rod 4 in the cylinder C is 2 and propelled rightward, the vehicle body B can be tilted counterclockwise. On the other hand, the hydraulic pressure is supplied to the other chamber R2 by using the solenoid switching valves 7 and 8 as the communication positions. When driven in this manner, hydraulic pressure is supplied into the other chamber R2, and the rod 4 in the cylinder C is propelled to the left in FIGS. 1 and 2, and the vehicle body B can be tilted clockwise. That is, the actuator A can function as an actuator that tilts the vehicle body.

  When the hydraulic pump 1 is driven to supply hydraulic pressure to the one chamber R1, the hydraulic pump 1 is connected to the other chamber R2 on the low pressure side or via the branch flow path 10 selected by the low pressure selection valve 12. Then, the hydraulic oil is sucked from the accumulator 11 or both, and the hydraulic oil is discharged to the one chamber R1 side. On the contrary, when the hydraulic pump 1 is driven so as to supply hydraulic pressure to the other chamber R2, the hydraulic pump 1 passes through the branch passage 9 selected from the one chamber R1 on the low pressure side or by the low pressure selection valve 12. The hydraulic fluid is sucked in from the accumulator 11 or both through the hydraulic fluid, and discharged to the other chamber R2 side.

  Therefore, even if the volume of the hydraulic pump 1 is reduced due to compression of the hydraulic oil, the hydraulic pump 1 is supplied with the hydraulic oil from the accumulator 11, and supplies hydraulic pressure to the desired pressure chamber of the one chamber R1 and the other chamber R2 without any problem. be able to.

  Further, when the thrust generation direction of the cylinder C is reversed, the pressure in the one chamber R1 and the pressure in the other chamber R2 are reversed, so that the low pressure selection valve 12 passes through both communication positions at one end neutral position. By switching, the branch passages 9 and 10 can be once communicated with the accumulator 11 to prevent pressure accumulation in the one chamber R1 and the other chamber R2.

  The low pressure selection valve 12 is an accumulator that prevents an increase in internal pressure due to an increase in the temperature of the hydraulic oil, prevents a negative pressure due to a decrease in the temperature of the hydraulic oil, and a volume difference between the one chamber R1 and the other chamber R2 due to manufacturing errors in the cylinder C. It is provided for supplying hydraulic oil from the factory.

  Further, in the case of this embodiment, a stroke sensor 30 for sensing displacement of the actuator A (displacement of the rod 4 with respect to the container 2 in the cylinder C) is provided. Based on the displacement of the actuator A detected by the stroke sensor 30, A motor 20 that drives the hydraulic pump 1 is controlled by a control unit 20 described later.

  The actuator A according to the present embodiment includes a damper circuit 13 that causes the cylinder C to function as a damper at the time of failure and the like. The damper circuit 13 will be described below. The damper circuit 13 includes two damper circuits 13 in the cylinder C. A flow path 14 that communicates the pressure chambers R1 and R2 is provided. The flow path 14 includes a main flow path 14a in which a damping force generating element 15 and a solenoid switching valve 16 are provided, and a main flow path 14a from the one chamber R1. Only the upper flow path 14b allowing only the flow toward the other side, the other upper flow path 14c allowing only the flow toward the main flow path 14a from the other chamber R2, and only allowing the flow toward the one chamber R1 from the main flow path 14a. 14d, and the other lower flow path 14e that allows only the flow from the main flow path 14a toward the other chamber R2. It has been.

  The one-side upper flow path 14b includes a check valve 17a that allows only the flow of hydraulic oil from the one chamber R1 toward the main flow path 14a on the way, and the check valve 17a causes the one-side upper flow path 14b to move from the one chamber R1. This is a one-way passage toward the main flow path 14a. Similarly, check valves 17b, 17c, and 17d are respectively provided in the middle of the other upper flow path 14c, the one lower flow path 14d, and the other lower flow path 14e, and serve as one-way paths as described above. Is set to

  In the present embodiment, since the flow path 14 is configured in this way, the hydraulic oil is upstream from the main flow path 14a connected to the one-side upper flow path 14b and the other-side upper flow path 14c. As described above, the main flow path 14a is also one-way, as it flows to the downstream side connected to the one-side lower flow path 14d and the other-side lower flow path 14e.

  The downstream of the main flow path 14a is connected to the accumulator 11 via the connection passage 14f, and the pressure downstream of the main flow path 14a is set to be the same as that of the accumulator 11.

  The damping force generating element 15 provided in the middle of the main channel 14a includes a damping valve 15a that adjusts the channel area according to its upstream pressure, and a fixed throttle 15b that is arranged in parallel with the damping valve 15a. When the pressure on the upstream side of the main flow path 14a is low, the damping valve 15a is not opened, the hydraulic oil is allowed to pass through the fixed throttle 15b, the flow rate is increased, and the pressure loss due to the fixed throttle 15b increases and the upstream is increased. When the pressure on the side exceeds the cracking pressure of the damping valve 15a, the damping valve 15a is opened, and the hydraulic oil flows to the downstream side of the main flow path 14a also through the damping valve 15a.

  Thus, the damping force generating element 15 gives a damping force that suppresses expansion and contraction of the cylinder C by giving resistance to the flow by the damping valve 15a and the fixed throttle 15b when the hydraulic oil flows through the main flow path 14a. It functions as a source to be demonstrated.

  Further, the solenoid switching valve 16 is a normally open switching valve, and adopts a communication position with a valve 16a having a communication position for opening the main flow path 14a and a blocking position for blocking the main flow path 14a. A spring 16b that biases the valve 16a and a solenoid 16c that switches the valve 16a to the cut-off position opposite to the spring 16b when energized are provided.

  Here, considering that the solenoid switching valves 7 and 8 are in the cutoff position and the cylinder C is not driven on the actuator circuit 5 side, the main flow path 14a is maintained in the cutoff state when the solenoid switching valve 16 takes the cutoff position. Then, since the communication between the one chamber R1 and the other chamber R2 of the cylinder C is cut off, the cylinder C is brought into a locked state in which it cannot expand and contract. On the other hand, when the solenoid switching valves 7 and 8 are in the shut-off position and the solenoid switching valve 16 is in the communication position at the time of so-called failure, the main flow path 14a is maintained in an open state, and the cylinder C is driven by an external force. When it is forcibly expanded and contracted, the hydraulic oil can move from the one chamber R1 to the other chamber R2 or from the other chamber R2 to the one chamber R1 via the flow path 14, and the main flow is always in the above movement. Since it passes through the damping force generation element 15 of the path 14a, the cylinder C exhibits a damping force that suppresses expansion and contraction against forced expansion and contraction due to external force, and the cylinder C can function as a damper.

  In addition, the damper circuit 13 includes a relief flow path 18 that connects the one chamber R 1 and the other chamber R 2, and a relief valve 19 provided in the middle of the relief flow path 18.

  Specifically, the relief flow path 18 bypasses the damping force generation element 15 and the solenoid switching valve 16, and communicates the one chamber R1 and the other chamber R2 by communicating the upstream and downstream of the main flow path 14a. ing.

  Regardless of whether the solenoid switching valve 16 is opened or closed, if the cylinder C has an excessive input in the expansion / contraction direction and the pressure in the one chamber R1 or the other chamber R2 becomes an abnormally high pressure exceeding a predetermined pressure, the relief valve 19 is opened. In operation, the pressure of one of the one chamber R1 or the other chamber R2 that has become an abnormally high pressure is released to the other of the low pressure side to protect the entire system of the actuator A. Further, when the volume of the hydraulic oil decreases, the solenoid switching valves 7 and 8 allow the one chamber R1 and the other chamber R2 to communicate with the accumulator 11 regardless of the communication position or the shut-off position. The hydraulic oil is supplied to the chamber R1 and the other chamber R2. As described above, in the actuator A according to this embodiment, the volume of the hydraulic oil is compensated by the temperature change by adopting the above circuit configuration. As described above, in the shut-off position of the solenoid switching valves 7 and 8, the accumulator 11 goes to the one chamber R1 and the other chamber R2 in order to enable volume compensation accompanying a temperature drop even if the loop passage 6 is shut off. Although the flow is allowed, when the volume compensation is not performed in the actuator circuit 5, the bidirectional flow in the loop passage 6 may be blocked at the blocking position.

Subsequently, as shown in FIG. 3, the control unit 20 that controls the motor M in the actuator A determines the target value of the vehicle body tilt angle from the traveling state of the vehicle body B, and the actuator A that is input from a host device (not shown). A deviation calculator 21 that calculates a deviation ε between the target displacement X ^* and the actual displacement X output from the stroke sensor 30 and a control command E that controls the actuator A based on the deviation ε calculated by the deviation calculator 21 are generated. A control command generation unit 22 that performs control, a limit value adjustment unit 23 that adjusts a current limit value, and a motor drive that receives the control command E output from the control command generation unit 22 and drives the motor M of the hydraulic pump 1 in the actuator A And a portion 24. In other words, the control unit 20 controls the displacement of the actuator A by feeding back the displacement X of the actuator A.

In addition, since the actual control target in the displacement feedback control is the motor M, the control command generation unit 22 specifically takes the deviation ε between the target displacement X ^* and the actual displacement X. Based on this deviation ε, a control command that is a target motor rotational speed command is generated by proportional integral operation or proportional integral differential operation, and a rotational speed deviation that is a deviation between the target motor rotational speed command and the actual rotational speed of the motor M The rotation speed deviation is input to the speed loop to generate a control command that is a target speed command, and the target speed command is input to the current loop to eventually drive the motor M. A control command is generated, and a control command E that is the target current command is output to the motor drive unit 24. By executing such processing to the control command generation section 22, but the actual displacement X of the actuator A can follow precisely the target displacement X ^*, the deviation of the actual displacement X and the target displacement X ^* epsilon It is also possible to generate a control command E consisting of a target current command directly by proportional integral operation or proportional integral differential operation.

  Although not shown, the motor drive unit 24 includes a drive circuit that drives the motor M. When the motor drive unit 24 receives a control command E indicating the current amount for actually driving the motor M, the motor drive unit 24 converts the current amount according to the control command to the motor. Supplied to M via a drive circuit.

The actuator A is connected to each solenoid switching valve 7, 8, 16 based on a control command output from a command system (not shown) that drives each solenoid switching valve 7, 8, 16 separately from the command system that controls the motor M. For example, when it is necessary to tilt the vehicle body B by expanding and contracting the cylinder C, for example, the target displacement X ^* output from the host device (not shown ⁾ and the actual displacement are provided. Based on the displacement X, it is determined that it is necessary to drive the cylinder C, and the solenoid switching valves 7 and 8 are switched to the communication position. Further, the solenoid switching valve 16 is in principle energized when the actuator A is operating normally.

  In this embodiment, when the motor M is rotated forward, the supply current has a positive value, and when the motor M is rotated reversely, the supply current has a negative value. . The current limit value is set on both the positive limit value when the motor M is rotated forward and the negative limit value when the motor M is rotated reversely. For convenience, the limit value when the motor M is rotated forward Since the upper limit of the current value is regulated with a positive value, the upper limit current limit value is set. When the motor M is reversely rotated, the limit value has a negative value to limit the lower limit of the current value. Call it.

  Subsequently, the limit value adjusting unit 23 extracts a component in a predetermined frequency band that deteriorates the riding comfort from the displacement signal output from the stroke sensor 30, and the predetermined frequency band component extracted by the bandpass filter 25. And a limit value calculation unit 26 that calculates a current limit value based on the amplitude of the displacement signal. The current limit value calculated by the limit value calculation unit 26 is input to the motor drive unit 24, and the motor drive unit 24 The amount of current applied to the motor M is limited within the upper limit and lower limit current limit values.

  That is, in this embodiment, the vibration of the vehicle body B relative to the carriage W is detected by detecting the displacement of the actuator A, and the current limit value is adjusted according to the vibration state of the actuator A. .

  The processing in the limit value adjusting unit 23 will be described in detail. First, the bandpass filter 25 applies only a predetermined frequency band component, specifically, for example, a vibration component in a frequency band of about 1 Hz to about 10 Hz to the stroke sensor 30. Is extracted from the displacement signal output.

Subsequently, the limit value calculation unit 26 calculates the amplitude of the vibration component in the predetermined frequency band of the displacement signal, performs weighting that gradually decreases with respect to the amplitude, and calculates the upper and lower limit current limit values ± I ^*. It has become. Specifically, a coefficient α that gradually decreases from the maximum value to the minimum value according to the magnitude of the amplitude L is obtained by using a map shown in FIG. 4, and the coefficient α is a positive value allowed by the motor M. maximum current value seeking current limit absolute value by integrating the I _max, the upper limit current limit value I ^* is the upper limit of the amount of current supplied to the motor M, the motor M by reversing the sign of the current limit absolute value The lower limit current limit value −I ^* , which is the lower limit of the supplied current amount, is calculated.

The coefficient α is integrated with the positive maximum current value I _max allowed by the motor M. In this case, the coefficient α is a coefficient in the range of 0 ≦ α ≦ 1, and the minimum value 0 is obtained by increasing the amplitude L. It will be gradually reduced toward.

Further, in the example shown in FIG. 4, the amplitude L is less than L _1, with the coefficient α assumes a 1 is the maximum value, any minimum value β becomes exceeds L _2, the amplitude L is L ₁ or L ₂ In the following range, the coefficient α decreases proportionally to an arbitrary minimum value β. However, in order to decrease gradually, the coefficient α is proportional, inversely proportional, or exponential with respect to an increase in the amplitude L. It also includes decreasing by function, stepwise, or any combination thereof.

Furthermore, in the place described above, to determine the upper current limit value I ^* and the lower current limit value -I ^*, end, seeking factor alpha, so that multiplies the maximum current value I _max on the coefficient alpha but leave mapped positive upper current limit value obtained by weighting the amplitude L I ^*, directly with obtaining the upper current limit value I ^* from the amplitude L, negative lower current limit value by inverting the sign -I ^* may be obtained. When the coefficient α is multiplied by an arbitrary value γ, the coefficient α may be set so as to gradually decrease with respect to the increase in the amplitude L in the range of 0 ≦ α ≦ I _max / γ.

That is, in the limit value adjustment unit 23, when vibration in a frequency band that deteriorates the ride comfort when transmitted to the vehicle body B due to disturbance acts on the carriage W, the bandpass filter 25 extracts the vibration component in the frequency band. Then, the limit value calculation unit 26 obtains the upper and lower limit current limit values ± I ^* , and limits the upper limit and the lower limit of the amount of current output from the actuator driver 24 to the motor M.

As described above, in the actuator A of the present embodiment, the upper limit and lower limit of the amount of current output to the motor M are limited to the upper and lower current limit values ± I ^* obtained by the limit value calculation unit 26. Limiting the amount of current means limiting the output torque of the motor M.

  When the output torque of the motor M is limited and reduced, when an external force is input to the cylinder C, the motor M can be easily expanded and contracted by the external force. Thus, the apparent rigidity of the actuator A can be reduced. It becomes possible.

  That is, in the actuator A in this embodiment, the apparent rigidity of the actuator A can be controlled by limiting the amount of current of the motor M.

Here, when vibrations in a frequency band that deteriorates the ride comfort when acting on the carriage W due to disturbance when the railway vehicle is traveling while the railway vehicle is traveling, if the apparent rigidity of the actuator A is high, the carriage W In this embodiment, since the applied vibration is transmitted to the vehicle body B, in such a case, the actuator A can be expanded and contracted by a disturbance, so the upper and lower limit current limit values ± I. ^* Is brought close to 0, that is, the absolute value of the current limit value is decreased, the amount of current supplied to the motor M is limited, and the generated torque of the motor M is decreased.

  Then, the apparent rigidity of the actuator A becomes low, the actuator A can easily expand and contract with respect to the vibration input to the carriage W, and the vibration propagation to the vehicle body B side can be insulated.

Therefore, in the actuator A of the present embodiment, the current limit value ± I ^* supplied to the motor is adjusted based on the amplitude of vibration in a predetermined frequency band. Even if it acts on W, it is possible to suppress the vibration input to the cart W side from propagating to the vehicle body B side, and to improve the riding comfort in the vehicle even if the hydraulic actuator A is used for tilting the vehicle body. Can do it.

  In other words, since the ride comfort in the vehicle can be improved, the working fluid of the actuator A can be a liquid working oil, which eliminates the lack of propulsive force and improves the response of the vehicle body tilt. Can do it.

Further, since the positive and negative current limit values ± I ^* are obtained by weighting so as to gradually decrease as the amplitude L increases, the vibration amplitude L in the frequency band is large, and there is a concern about deterioration of riding comfort. In this case, the apparent rigidity of the actuator A is further lowered to improve the vibration insulation, and conversely, when the amplitude L of the vibration in the frequency band is small, the actuator 20 for tilting the vehicle body by the control unit 20 is used. It is possible to secure the apparent rigidity of the actuator A to the extent that the follow-up of the actual displacement X of the actuator A is satisfied with respect to the target displacement X ^* calculated by the host device by giving priority to the control.

Further, in the limit value calculation unit 26 described above, the target displacement X ^* calculated by the deviation calculation unit 21 in the control unit 20 and the actual displacement X are obtained separately from obtaining the positive and negative current limit values ± I ^* by the above processing. When the deviation ε is less than or equal to a predetermined threshold value, the positive and negative current limit values ± I ^* obtained as described above are validated, and the amount of current that the motor drive unit 24 supplies to the motor M is It is limited by positive and negative current limit values ± I ^* .

On the other hand, when the deviation ε exceeds a predetermined threshold, the positive / negative current limit value ± I ^* is not the value obtained by the above processing, but the upper limit current limit value is set to the maximum current value I _max having a positive value. At the same time, the lower limit current limit value is set to a minimum current value I _min having a negative value, and the upper limit and the lower limit of the amount of current that the actuator driver 24 supplies to the motor M are limited by the maximum current value I _max and the minimum current value I _min. It will be.

  That is, in this case, current can be supplied to the motor M up to the maximum and minimum current amounts allowed, and the apparent rigidity of the actuator A is maintained high.

The predetermined threshold value is a reference for determining whether or not to give priority to the control of the actuator A for the vehicle body tilt by the control unit 20, and this threshold value represents the amount of current supplied to the motor M as a current value. By performing control to suppress vibration transmission from the carriage W to the vehicle body B by adjusting the limit value ± I ^* , the follow-up of the actual displacement X of the actuator A with respect to the target displacement X ^* is sacrificed. When the ride quality is deteriorated, the value is set such that the control of the actuator A for the vehicle body tilt by the control unit 20 can be prioritized.

Thus, in the case of this embodiment, the limit value calculation unit 26 takes in the deviation ε of the target displacement X ^* and the actual displacement X in addition to obtaining the upper and lower limit current limit values ± I ^* , When the deviation ε exceeds the threshold value, the control of the actuator A for tilting the vehicle body by the control unit 20 is prioritized and the actual displacement X of the actuator A follows the target displacement X ^* calculated by the host device. When the deviation ε is equal to or less than the above threshold value, priority is given to control for suppressing vibration transmission from the carriage W to the vehicle body B. It is possible to further improve the ride comfort by balancing the high and low dimensions.

  The control unit 20 according to the present embodiment is not illustrated as a hardware resource, but an A / D converter that converts a displacement signal that is an analog voltage output from the stroke sensor 30 into a digital signal, and a displacement A CPU (Central Processing Unit) that captures signals and target displacements from the host device and executes the processing of each unit, a RAM (Synchronous Dynamic Random Access Memory) that provides a storage area for the CPU, and the processing of each unit A ROM (Read Only Memory) that stores programs executed by the CPU and programs such as an operating system and a motor drive unit 24 are configured. The configuration of each unit of the control unit 20 includes: processing This is realized by executing an application program to perform the above.

  In this case, the band-pass filter 25 is realized by processing by the CPU, but may be a filter that processes an analog signal output from the stroke sensor 30.

Next, the processing for obtaining the upper and lower limit current limit values ± I ^* in the control unit 20 will be described with reference to an example of the processing procedure shown in FIG. 5. In step S1, the control unit 20 detects the stroke sensor. A displacement signal of a vibration component in a predetermined frequency band is extracted from the displacement signal output by 30.

  And it transfers to step S2 and the control part 20 obtains the amplitude L in the displacement signal of the vibration component of a predetermined frequency band. The amplitude L may be obtained by calculating the difference between the minimum value and the maximum value within an arbitrary period in the displacement signal of the vibration component in the predetermined frequency band, and calculating the power spectrum of the vibration component in the predetermined frequency band. You may ask for.

Subsequently, in step S3, a coefficient α is obtained from the amplitude L obtained in step S2, an upper limit current limit value I ^* is obtained from the coefficient α, and the sign is inverted to calculate a lower limit current limit value −I ^* .

In step S4, the deviation ε calculated by the deviation calculating unit 21 in the control unit 20 is read. If the deviation ε is equal to or less than the threshold value, the process proceeds to step S5, and the calculation result in step S3 is directly used for each current limit value. ± and I ^*, with the maximum current value I _max of the upper current limit value I ^* values and proceeds to step S6 if the deviation ε exceeds the threshold value, lower current limit value -I ^* minimum value current _Let it be the value I _min .

Finally, the process proceeds to step S7, and the upper and lower limit current limit values ± I ^* are output to the actuator driver 24.

As described above, when the series of determination processes is completed, the same process is repeatedly performed. In this way, the control unit 20 continuously adjusts the upper and lower limit current limit values ± I ^*. Is done.

In the above description, in order to obtain the vibration of the vehicle body B with respect to the carriage W, the displacement is detected by the stroke sensor 30 provided in the cylinder C. However, the pressure in the one chamber R1 and the other chamber R2 of the cylinder C is determined. Since the vibration component of the vehicle body B with respect to the carriage W is also superimposed on the fluctuation of the vehicle body, as shown in FIG. 1, the pressure sensor 31 for sensing the pressure in the one chamber R1 and the pressure sensor for sensing the pressure in the other chamber R2 32, and the pressure sensors 31 and 32 may detect the pressure in the one chamber R1 and the other chamber R2 to obtain vibration of the vehicle body B relative to the carriage W. Since the displacement feedback control is performed, the carriage of the vehicle body B is also used for each control command generated in the control command generating unit 22 in the control unit 20, that is, the target motor rotational speed command, the target speed command, and the target current command. Since the vibration with respect to W is superimposed, the vibration of the vehicle body B with respect to the carriage W may be obtained by monitoring one of these control commands. Furthermore, since the displacement feedback control is performed as described above, the deviation ε between the target displacement X ^{* of the} actuator A and the actual displacement X input to the control command generation unit 22 in the control unit 20 is also determined by the vehicle body B. Since the vibration with respect to the carriage W is superimposed, the vibration of the vehicle body B with respect to the carriage W may be obtained from the deviation ε. Still further, an acceleration sensor may be attached to the vehicle body B to directly detect vibration of the vehicle body B, and the application to the control unit 20 may be the same as described above. As described above, there are a plurality of means for obtaining the vibration of the vehicle body B with respect to the carriage W. When actually applied to the control unit 20 of the above-described embodiment, the vibration obtained by these other means. Data may be input to the bandpass filter 25 instead of the actual displacement X. For example, when vibration is obtained from the deviation ε between the target displacement X ^* of the actuator A and the actual displacement X, specifically, FIG. As shown in FIG. 6, the deviation ε itself may be directly input to the bandpass filter 25. If necessary, when the upper limit and lower limit current limit values ± I ^* are calculated in the limit value calculation unit 26, the weighting coefficient may be appropriately changed so as to be suitable for the means for obtaining the vibration.

  In the above description, the actuator A according to the present embodiment is applied to a railway vehicle that employs a so-called pendulum method as a vehicle body tilting method. Naturally, the actuator A of the present invention can also be applied to a case where two actuators are installed vertically and the body B is tilted by driving each actuator.

  This is the end of the description of the embodiment of the present invention, but the scope of the present invention is of course not limited to the details shown or described.

It is a figure which shows the hydraulic circuit of the actuator in one embodiment. It is a figure which shows the state which interposed the actuator in one Embodiment between the vehicle body of a railway vehicle, and the trolley | bogie. It is a control block diagram in the actuator of one embodiment. It is a figure which shows the relationship between the amplitude of the vibration component of the predetermined frequency band in a displacement signal, and the coefficient which weights with respect to the said amplitude. It is a figure which shows an example of the flowchart which controls the electric current limit value in the control part which controls the motor of the actuator in one Embodiment. It is a control block diagram of an actuator in one modification of an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydraulic pump which is a hydraulic pressure source 2 Container 3 Piston 4 Rod 5 Actuator circuit 6 Loop passage 7, 8, 16 Solenoid switching valve 7a, 8a, 16a Valve 7b, 8b, 16b Spring 7c, 8c, 16c Solenoid 9, 10 Branch passage 11 Accumulator 12 Low pressure selection valve 13 Damper circuit 14 Flow path 14a Main flow path 14b One side upper flow path 14c The other side upper flow path 14d One side lower flow path 14e The other side lower flow path 14f Connection path 15 Damping force generating element 15a Damping valve 15b Fixed throttle 17a, 17b, 17c, 17d Check valve 18 Relief flow path 19 Relief valve 20 Control unit 21 Deviation calculation unit 22 Control command generation unit 23 Limit value adjustment unit 24 Motor drive unit 25 Bandpass filter 26 Limit value calculation unit 30 Stroke sensor 31, 32 Pressure sensor A Actuator B Car body C Cylinder R1 Pressure chamber one chamber R2 Pressure chamber other chamber W

Claims (8)

An actuator that includes a cylinder interposed between a vehicle body of a railway vehicle and a carriage and a hydraulic pump that is driven by a motor that supplies hydraulic pressure to the cylinder. An actuator that adjusts a current limit value that limits an amount of current supplied to a motor based on an amplitude of vibration in a predetermined frequency band among vibrations of a vehicle body. 2. The actuator according to claim 1, wherein a vibration amplitude in a predetermined frequency band is obtained from vibrations of the vehicle body or vibrations of the vehicle body, a current limit value is obtained by weighting the amplitude gradually, and the limit value is adjusted. . The upper limit side current limit value is set to the maximum value and the lower limit side current limit value is set to the minimum value when the deviation between the target displacement of the actuator and the actual displacement of the actuator exceeds the threshold value. Actuator. 4. The actuator according to claim 1, wherein vibration of the vehicle body is obtained by detecting acceleration acting on the vehicle body. The actuator according to any one of claims 1 to 3, wherein a vibration of the vehicle body is obtained by detecting a pressure in the actuator. 4. The actuator according to claim 1, wherein vibration of the vehicle body is obtained by detecting displacement of the actuator. The actuator according to any one of claims 1 to 3, wherein a vibration of the vehicle body is obtained from a control command generated by a control device that controls the actuator. The actuator according to any one of claims 1 to 3, wherein a vibration of the vehicle body is obtained from a deviation between a target displacement of the actuator and an actual displacement of the actuator.

Images