JP2009196597A - Cylinder device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylinder device capable of generating sufficient damping force, even during a high speed elongation time, and efficiently performing regeneration by a motor. <P>SOLUTION: This cylinder device C is provided with a cylinder 1, a piston 2 movably inserted into the cylinder 1 to section the cylinder 1 into two pressure chambers R1 and R2, a flow passage 3 for communicating the two pressure chambers R1 and R2 with each other, a bidirectional discharge type pump 5 provided in the middle of the flow passage 3 to be driven by the motor 4, and variable throttle valves 6 and 7 provided in parallel or in series with the pump 5 provided in the middle of the flow passage 3 or in parallel and in series with the pump 5. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a cylinder device.

  This type of cylinder device is applied, for example, to an active suspension or the like interposed between a vehicle body and an axle of a vehicle. Specifically, the cylinder device is inserted into the cylinder so as to be freely movable. A piston that is divided into two pressure chambers, a rod that is connected to the piston, a channel that communicates the two pressure chambers, and a bidirectional discharge pump that is provided in the middle of the channel and is driven by a motor. (For example, refer patent document 1).

  When this cylinder device is applied to an active suspension, the cylinder is connected to one of the vehicle body and the axle, the rod is connected to the other of the vehicle body and the axle, and the pump is driven by a motor to drive the cylinder device to drive the vehicle. Controls the vehicle body posture at.

In this cylinder device, when controlling the vehicle body posture, when the cylinder device is forcibly expanded and contracted by an external input, the pump is driven to resist the external input by giving resistance to the flow of hydraulic oil passing through the flow path. The vehicle body vibration can be suppressed by adjusting the torque of the motor according to the magnitude of the external input.
JP-A-2000-264033 (page 4, left column, lines 8 to 24 and FIG. 1)

  In the cylinder device described above, the torque of the motor is used as the control force of the cylinder device through the pump, but due to the characteristics of the motor, the generated torque tends to decrease as the rotational speed increases. When the cylinder device is expanded and contracted at high speed by an external input, there is a possibility that a damping force necessary for vibration suppression cannot be obtained.

  Further, in the above cylinder device, the torque to be borne by the motor cannot be controlled independently, and the rotation speed and torque of the motor are uniquely determined by the expansion / contraction speed of the cylinder device and the command of the controller. Therefore, regeneration by the motor cannot be performed efficiently.

  In the conventional cylinder device, a throttle valve is arranged in series with the pump in the middle of the flow path, and although the burden on the motor is reduced to some extent by this throttle valve, the above problem is It cannot be solved.

  In view of this, the present invention has been developed to improve the above-described problems, and the object is to generate a sufficient damping force even during high-speed expansion and contraction and to efficiently perform regeneration by a motor. It is to provide a cylinder device that can.

  In order to achieve the above object, a cylinder device according to the first problem solving means of the present invention includes a cylinder, a piston that is movably inserted into the cylinder and divides the inside of the cylinder into two pressure chambers, and two pressures. In a cylinder device comprising a flow path communicating with a chamber and a bidirectional discharge pump provided in the middle of the flow path and driven by a motor, the cylinder device is variable in parallel or in series with the pump in the middle of the flow path. A throttle valve was provided.

  The cylinder device in the second problem solving means of the present invention includes a cylinder, a piston that is movably inserted into the cylinder and divides the inside of the cylinder into two pressure chambers, and a flow path that connects the two pressure chambers. In addition, a variable throttle valve was provided in parallel and in series with the pump in the middle of the flow path in the cylinder device provided with the bidirectional discharge pump provided in the middle of the flow path and driven by the motor.

  According to the cylinder device of the present invention, the intersection of the rotational speed of the motor and the torque to be borne can be kept within the outputable torque range by changing the throttle coefficient of the variable throttle valve. Sufficient damping force can be generated.

  In addition, the intersection of the rotation speed of the motor and the torque to be borne can be stored in the regenerative area by changing the throttle coefficient of the variable throttle valve, so it can be regenerated when the motor is used in the braking area. Regeneration can be performed efficiently.

  The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a conceptual diagram of a cylinder device according to an embodiment. FIG. 2 is a model diagram showing the relationship between the flow rate of the cylinder device and the differential pressure in the embodiment. FIG. 3 is a graph in which the number of rotations of the motor is made to correspond to the flow rate of the pump and the torque of the motor is made to correspond to the differential pressure (pressure loss) when the fluid passes through the pump. FIG. 4 is a diagram showing a torque output possible range of the motor in the braking region. FIG. 5 is a diagram illustrating a motor regeneration region. FIG. 6 is a diagram showing the relationship between the motor torque and the regenerative current value.

  As shown in FIG. 1, a cylinder device C according to an embodiment includes a cylinder 1, a piston 2 that is movably inserted into the cylinder 1 and divides the cylinder 1 into two pressure chambers R1, R2, and two A flow path 3 communicating with the two pressure chambers R1 and R2, a bidirectional discharge pump 5 provided in the middle of the flow path 3 and driven by a motor 4, and a pump 5 in series in the middle of the flow path 3. And variable throttle valves 6 and 7 provided in parallel. The cylinder 1 is filled with a fluid and sealed.

  The piston 2 is connected to a rod 8 that is movably inserted into the cylinder 1. In the case of this cylinder device C, a so-called double rod type cylinder device in which the rod 8 protrudes from both ends of the cylinder 1. Has been.

  When the cylinder device C is applied to a vehicle, the cylinder 1 is connected to one of the sprung member and the unsprung member of the vehicle, the rod 8 is connected to the other of the sprung member and the unsprung member, and the spring is connected. What is necessary is just to interpose between an upper member and an unsprung member. The cylinder device C is set to a double rod type in the illustrated embodiment, but may be set to a single rod type.

  The pump 5 is set to a bidirectional discharge type. For example, the pump 5 includes a rotary shaft (not shown) such as a vane pump, a gear pump, or an axial pump, and can suck and discharge fluid by rotation of the rotary shaft. Anything that can forcibly drive the rotating shaft by the flow is acceptable.

  Further, the rotating shaft of the pump 5 is connected to the motor 4, and the motor 4 can be driven by energization, and when it is forcibly driven to rotate by an input from the pump 5 side, it generates electricity and generates the pump 5. Any motor may be used as long as it generates a torque that suppresses the rotation of the motor, and various types of motors, for example, a brushless motor, an induction motor, a synchronous motor, and the like can be employed regardless of direct current or alternating current.

  The motor 4 is connected to the control device 10 and drives the motor 4 to feed a fluid from the pressure chamber R1 to the pressure chamber R2 or from the pressure chamber R2 to the pressure chamber R1 by the pump 5. When the device C can be expanded and contracted, and the cylinder device C is forcibly expanded and contracted by an external input, the flow path 3 is moved from the pressure chamber R1 to the pressure chamber R2 or from the pressure chamber R2 to the pressure chamber R1. A damping force can be generated by applying resistance to the pump 5 to which the torque of the motor 4 is transmitted to the flow of the fluid moving through the fluid.

  Further, when the cylinder device C is forcibly expanded and contracted, the motor 4 is forcibly driven via the pump 5 by the flow of fluid flowing back and forth in the flow path 3, so that the kinetic energy of the fluid is converted into electric energy by the motor 4. It is possible to perform regeneration to convert to. The electric power regenerated by the motor 4 may be transmitted to an external device or stored in a capacitor.

  In turn, the variable throttle valve 6 is provided in series with the pump 5 in the middle of the flow path 3, and the variable throttle valve 7 is provided in the middle of the bypass circuit 9 that bypasses the pump 5. The throttle valve 6 is arranged in parallel. These variable throttle valves 6 and 7 can change the throttle coefficient, which is the ratio of the flow rate to the pressure loss, by changing the opening degree and the valve passage length. Various valves such as a variable choke and a variable orifice can be used, and the throttle coefficient can be changed by driving a valve element (not shown) with a drive source such as a solenoid or a motor. These variable throttle valves 6, 7 are connected to the control device 10 for driving the throttle coefficient and are driven by the control device 10 together with the motor 4.

  Now, the cylinder device C configured as described above can function as an actuator that expands and contracts itself when power is supplied to the motor 4 from the outside and the pump 5 is driven. When it is expanded and contracted by an external input, the rotation of the pump 5 is suppressed by the torque of the motor 4, that is, the motor 4 is used in the braking region so that the motor 4 generates a torque opposite to the rotation direction of the pump 5, The motor 4 and the variable throttle valves 6 and 7 can cooperate to generate a damping force. The load on the motor 4 can be controlled by controlling the variable throttle valves 6 and 7 and adjusting the throttle coefficient in the variable throttle valves 6 and 7.

  When the cylinder device C functions as an actuator, the variable throttle valve 7 is fully closed to cut off the communication between the pressure chambers R1 and R2 via the bypass circuit 9, and the variable throttle valve 6 is fully opened to make the variable throttle valve 6 fully open. Thus, care is taken not to cause energy loss by giving unnecessary resistance to the flow of fluid.

  Here, control of the load (rotation speed and torque to be borne) of the motor 4 when the cylinder device C is expanded and contracted by an external input will be described with reference to a model diagram shown in FIG.

  In addition, since the pump 5 gives resistance to the flow of the fluid by the torque transmitted from the motor 4 and causes a pressure loss when the fluid passes, it can be handled in the same way as a variable throttle valve. The motor 4 and the pump are described as one variable throttle valve M.

ここで、Ｃ＝Ｃ２×Ｃｍ／（Ｃ２＋Ｃｍ）とおくと、（１）式は下記（２）式と書くことができる。

さらに、全体の流量Ｑ＝ｑ１＋ｑ２が成り立ち、可変絞り弁７で生じる差圧Ｐは、可変絞り弁６とモータ４とポンプ５でなる可変絞り弁Ｍの全体で生じる差圧に等しいので、以下の（３）式が成立する。

（３）式を（２）式に代入してまとめると、以下の（４）式を得る。

そして、上記（４）式から理解できるように、流量Ｑおよび差圧Ｐを変化させない場合、絞り係数Ｃ１を変更することで、流量ｑ２を変更することができる。 A differential pressure between one pressure chamber R1 and the other pressure chamber R2 when the cylinder device C is expanded and contracted is P, and a flow rate per unit time of fluid flowing out from the one pressure chamber R1 (hereinafter simply referred to as a flow rate). And Q, and a throttle coefficient which is a ratio obtained by dividing the flow rate q1 of the fluid passing through the variable throttle valve 7 by the differential pressure (pressure loss) P generated in the variable throttle valve 7 is C1, and the fluid flow through the variable throttle valve 6 is The throttle coefficient which is a ratio obtained by dividing the flow rate q2 by the differential pressure (pressure loss) p2 generated by the variable throttle valve 6 is C2, and the flow rate q2 of the fluid passing through the variable throttle valve M composed of the motor 4 and the pump 5 is variable. When a throttling coefficient which is a ratio divided by a differential pressure (pressure loss) pm generated by M is Cm, the following equation (1) is obtained.

Here, if C = C2 × Cm / (C2 + Cm), the expression (1) can be written as the following expression (2).

Further, the entire flow rate Q = q1 + q2 is established, and the differential pressure P generated in the variable throttle valve 7 is equal to the differential pressure generated in the entire variable throttle valve M including the variable throttle valve 6, the motor 4, and the pump 5. (3) Formula is materialized.

Substituting the formula (3) into the formula (2) and putting it together yields the following formula (4).

As can be understood from the above equation (4), when the flow rate Q and the differential pressure P are not changed, the flow rate q2 can be changed by changing the throttle coefficient C1.

  That is, by adjusting the flow rate q1 in the variable throttle valve 7 that bypasses the pump 5 by changing the throttle coefficient C1, the flow rate q2 passing through the variable throttle valve M can be changed. For example, the variable throttle valve 7 Is shifted from the fully closed state to the fully opened state, the flow rate q2 can be increased or decreased to increase or decrease the rotational speed of the motor 4.

そして、上記（５）式から理解できるように、流量ｑ２および差圧Ｐを変化させない場合、絞り係数Ｃ２を変更することで、可変絞り弁Ｍにおける差圧ｐｍを変更することができる。 Further, the flow rate in the variable throttle valve 6 and the variable throttle valve M is q2, the overall differential pressure is P, the differential pressure (pressure loss) in the variable throttle valve M is pm, and the variable throttle valve 6 and the variable throttle valve are variable. Since the combined throttle coefficient C of the valve M is C = C2 × Cm / (C2 + Cm) as described above, the following formula (5) is obtained by focusing on the variable throttle valve 6 and the variable throttle valve M. .

As can be understood from the above equation (5), when the flow rate q2 and the differential pressure P are not changed, the differential pressure pm in the variable throttle valve M can be changed by changing the throttle coefficient C2.

  That is, the differential pressure pm generated when the fluid passes through the pump 5 can be changed by changing the throttle coefficient C2. For example, when the variable throttle valve 6 is shifted from the fully closed state to the fully open state, the differential pressure The torque to be borne by the motor 4 can be increased or decreased by increasing or decreasing pm.

  In the state where the flow rate Q and the differential pressure P are kept constant, the rotational speed of the motor 4 is made to correspond to the passing flow rate of the pump 5, and the differential pressure when the fluid passes through the pump 5 to the torque of the motor 4 Referring to the graph shown in FIG. 3 corresponding to (pressure loss), the torque (burden torque) to be borne by the motor 4 by changing the throttle coefficient C2 of the variable throttle valve 6 along the vertical axis. This means that the rotation speed of the motor 4 can be adjusted along the horizontal axis by changing the throttle coefficient C1 of the variable throttle valve 7.

  Specifically, the point a in FIG. 3 indicates the rotational speed of the motor 4 in a state where the variable throttle valve 6 is fully opened and the throttle coefficient C2 is maximized, and the variable throttle valve 7 is fully closed and the throttle coefficient C1 is minimized. The point b represents the rotational speed of the motor 4 when the variable throttle valve 6 is fully opened and the throttle coefficient C2 is maximized, and the variable throttle valve 7 is fully opened and the throttle coefficient C1 is maximized. The relationship with the burden torque is shown. Point c represents the rotation of the motor 4 in a state where the variable throttle valve 6 is fully closed and the throttle coefficient C2 is minimized, and the variable throttle valve 7 is fully closed and the throttle coefficient C1 is minimized. The point d indicates the relationship between the motor 4 in the state where the variable throttle valve 6 is fully closed and the throttle coefficient C2 is minimized, and the variable throttle valve 7 is fully opened and the throttle coefficient C1 is maximized. The relationship between a rotation speed and a burden torque is shown. That is, by changing the throttle coefficients C1 and C2 in the variable throttle valves 6 and 7, the rotational speed and the burden torque of the motor 4 can be adjusted within the range surrounded by the points a, b, c and d.

  Specifically, when the intersection of the rotational speed of the motor 4 and the burden torque is at point a, if the throttle coefficient C1 in the variable throttle valve 7 is increased, the variable throttle can be shifted to the point b side. When the throttle coefficient C2 in the valve 6 is decreased, the valve can be shifted to the point c side. When the throttle coefficient C1 in the variable throttle valve 7 is increased and the throttle coefficient C2 in the variable throttle valve 6 is decreased, the point d is obtained. It can be shifted to the side. That is, by controlling the variable throttle valves 6 and 7, the rotational speed and the burden torque of the motor 4 can be controlled.

  In the description of FIG. 3, it is assumed that the flow rate Q and the differential pressure P are constant. Therefore, although the load torque of the motor 4 is 0, the rotating state and the rotational speed are 0. Since the state with the burden torque does not occur, the line connecting the point b and the point d and the line connecting the point d and the point c indicate the boundary of the range where the intersection of the rotation speed and the burden torque in the motor 4 can be taken, The intersection of the rotation speed and the burden torque in the motor 4 does not take the value on the above line.

  By the way, the torque range that can be output with respect to an arbitrary number of rotations of the motor 4 in the braking region is such that when the torque is taken on the vertical axis and the rotation number is taken on the horizontal axis, as shown in FIG. , An area indicated by a diagonal line surrounded by a horizontal axis, a line e parallel to the horizontal axis, and a curve f continuous to the line e. The line e indicates the upper limit of the torque of the motor 4 and is a boundary generated due to the current being limited by a current limiter (not shown) provided in the control device 10. The curve f is also a line that partitions the torque region that can be generated and the torque region that cannot be generated, and is a boundary line determined by characteristics such as a power supply voltage (not shown) and an induced power of the motor 4. As can be understood from FIG. 4, the upper limit of the torque that can be output by the motor 4 becomes smaller as the rotational speed becomes higher. That is, when the total flow rate passing through the flow path 3 is passed to the pump 5, the higher the expansion / contraction speed of the cylinder device C, the higher the rotational speed of the motor 4 and the lower the output torque of the motor 4.

  Here, it is considered that the variable throttle valve 7 is fully closed and the variable throttle valve 6 is fully opened, so that the total flow rate of the fluid flow generated by the expansion and contraction of the cylinder device C flows to the pump 5. Then, since the entire flow rate passes through the pump 5, the rotation speed of the motor 4 is determined from the expansion / contraction speed of the cylinder device C, and the motor 4 bears from the damping force required when suppressing expansion / contraction of the cylinder device C. The torque that should be decided.

  As described above, when the point g, which is the intersection of the rotational speed required for the motor 4 and the burden torque, deviates from the outputable torque range shown in FIG. 4, no matter how the motor 4 is controlled, The required damping force cannot be exhibited.

  In such a case, in the cylinder device C, the control device 10 adjusts the throttle coefficient C2 of the variable throttle valve 6 to a small value, adjusts the throttle coefficient C1 of the variable throttle valve 7 to a large value, or both. As shown in FIG. 4, the intersection of the rotational speed required for the motor 4 and the burden torque is guided to the outputable torque range, and is changed to, for example, a point g ′ within the range. That is, in this cylinder device C, when the torque to be borne with respect to the rotation speed of the motor 4 cannot be output, the rotation speed or load of the motor 4 is controlled by the control of the variable throttle valves 6 and 7 as described above. The torque that should be borne by the motor 4 can be kept within the torque range that can be output by adjusting the torque to be borne, or both, and a situation where the generated damping force of the cylinder device C becomes insufficient can be prevented.

  Therefore, this cylinder device C can generate a sufficient damping force even during high-speed expansion and contraction.

  By the way, when the cylinder device C is expanded and contracted by an external input and the fluid rotates the pump 5 to rotate a rotor (not shown) of the motor 4, an induced electromotive force is generated in a winding (not shown) of the motor 4 and a regenerative current is generated. As shown in FIG. 5, the regenerative region where the regeneration can be performed by the induced electromotive force of the winding of the motor 4, the torque is plotted on the vertical axis and the rotational speed is plotted on the horizontal axis, as shown in FIG. This is the range of the hatched portion in FIG. 5 surrounded by the tangent line S and the horizontal axis that are in contact with the rotational speed torque curve in the short circuit characteristic T of the motor 4. Note that when the motor 4 is driven by PWM, in a region where the rotation speed of the motor 4 exceeds the no-load maximum rotation speed, the motor 4 cannot be controlled with the PWM output saturated, and torque is generated. An area where power cannot be generated occurs, and electric power cannot be regenerated even when induced power is generated. Therefore, an area where power cannot be regenerated is generated on the right side of the curve h in FIG. Further, in the present specification, the term “short-circuit characteristic” refers to the relationship between the output torque and the rotational speed of the motor 4 in a state where the winding of the motor 4 is short-circuited.

  As can be understood from the above, when the motor 4 is used in the braking region, if the above-described variable throttle valves 6 and 7 are controlled and the motor 4 is used in the regeneration region, electric power is regenerated and energy is recovered. Can be recovered. Therefore, when the intersection between the rotation speed required for the motor 4 and the burden torque deviates from the outputtable torque range, the control device 10 simply adjusts the intersection so that it is located within the outputtable torque range. In addition, the intersection point is guided to a narrow regeneration region so that power can be regenerated. Therefore, according to this cylinder device C, when the motor 4 is used in the braking region, regeneration by the motor 4 can always be realized, and regeneration can be performed efficiently.

  Furthermore, in order to increase the regenerative efficiency, the intersection of the rotational speed of the motor 4 and the burden torque may be placed on a line where the regenerative current value is maximum. Specifically, as can be understood from FIG. 6 showing the relationship of the regenerative current value to the motor torque, the maximum regenerative current value in the torque range where the regenerative current value is 0 or more is the maximum torque. When the torque is half, and the maximum torque in the regenerative region is on the tangent line S in FIG. 5, the regenerative efficiency is maximized because the straight line i in FIG. It becomes. That is, if the throttle coefficients C1 and C2 of the variable throttle valves 6 and 7 are controlled such that the intersection of the rotational speed of the motor 4 and the burden torque is on the straight line i, the regenerative current value becomes maximum and the regenerative efficiency is increased. be able to.

  For this reason, the control device 10 holds the rotation speed and torque of the motor 4 at which the regenerative efficiency is maximized as a map, and controls the variable throttle valves 6 and 7 with reference to this map so that the motor 4 Is adjusted so that the intersection of the rotation speed and the load torque is on a straight line i shown in FIG.

  Specifically, priority is given to either the number of rotations of the motor 4 or the burden torque, and the regenerative efficiency is maximized, and then the other one of the number of rotations or the burden torque is set. Adjustment may be made so that the intersection of the rotational speed of the motor 4 and the burden torque is placed on the straight line i.

  In addition, as described above, when the intersection of the rotational speed of the motor 4 and the burden torque is placed on the straight line i, the regenerative efficiency is maximized. Even if it guide | induces in the range used as 50% or more of the enclosed regeneration efficiency, regeneration efficiency can be raised.

  Note that the regenerative efficiency is 50% or more when the regenerative current value generated with respect to the torque generated by the motor 4 at an arbitrary rotational speed is 100% as shown in FIG. The regenerative current value is 50% or more of the maximum regenerative current value. In FIG. 5, the straight line j and the straight line k are locus of points determined by the rotational speed and the torque that achieves the regenerative efficiency 50%. is there. In order to derive the intersection of the rotational speed of the motor 4 and the burden torque within the range of the regeneration efficiency of 50% or more, it may be performed in the same manner as the guidance on the straight line i having the regeneration efficiency of 100%.

  From the above, the information necessary for adjusting the intersection of the rotational speed of the motor 4 and the burden torque in the control device 10 includes the flow rate Q and the motor 4 in addition to the characteristics of the motor 4 and the variable throttle valves 6 and 7. This is the differential pressure P between the pressure chamber R1 and the pressure chamber R2 that realizes the damping force required to be generated when used in the braking region.

  However, the control device 10 includes a drive circuit (not shown) so that the motor 4 and the variable throttle valves 6 and 7 can be driven to realize the above-described control, and the expansion / contraction speed of the cylinder device C or the flow path 3. The sensor 11 for monitoring the flow rate passing through the motor 4 is provided, and the intersection of the rotation speed of the motor 4 and the load torque is output within the torque range that can be output from the expansion / contraction speed or flow rate and the damping force that should be generated by the cylinder device C. Or the throttle coefficients C1 and C2 that can be guided to a range where the regenerative efficiency is 50% or more, calculate the rotation speed and load torque of the motor 4, and control the variable throttle valves 6 and 7 and the motor 4. Good.

  Further, the motor 4 is controlled via a drive circuit in order to realize the rotational speed obtained by the control device 10 and the torque to be borne, but when calculating the aperture coefficients C1 and C2, To keep the intersection of the rotation speed of the motor 4 and the burden torque within the outputable torque range, the characteristics of the motor 4 may be mapped and obtained by map calculation, or the outputable torque range in advance. The aperture coefficients C1 and C2 may be obtained so as to be guided to a point set within or within the regeneration region.

  Since the motor 4 is controlled by torque, the control can be performed by a known control system that feeds back the current of the motor 4 separately from the variable throttle valves 6 and 7. In the case where the motor 4 is a brushless motor, in addition to the current, the electrical angle of the rotor may be taken in for the control. For the variable throttle valves 6 and 7, for example, when the drive source is a solenoid, the relationship between the current supplied to the solenoid by the control device 10 and the throttle coefficients C1 and C2 is held as a map, and is obtained by calculation. The current to be supplied to the solenoid may be obtained by calculating a map from the aperture coefficients C1 and C2, and the obtained current may be supplied through the drive circuit. The current flowing through the solenoid may be fed back and controlled. Good. When the cylinder device C is driven actively, the control device 10 fully closes the variable throttle valve 7 and fully opens the variable throttle valve 6 as described above, so that the thrust and speed to be output by the cylinder device C are set. Based on this, the rotation speed and torque of the motor 4 may be controlled. The control device 10 may determine the damping force to be generated by the cylinder device C by itself or may receive an input from an external device.

  Incidentally, the control device 10 is, as hardware, specifically, for example, an amplifier for amplifying a signal output from the sensor 11, a converter for converting an analog signal into a digital signal, and a CPU (Central Processing Unit). A RAM (Synchronous Dynamic Random Access Memory) that provides a storage area for the CPU, a ROM (Read Only Memory) that stores programs such as an application and an operating system executed by the CPU to perform the processing of each unit, and a motor 4 And a drive circuit that drives the drive source of the variable throttle valves 6 and 7, and the CPU implements the processing necessary for performing the control by executing the application program. You can do so.

  Note that even if the bypass circuit 9 and the variable throttle valve 7 are eliminated and only the variable throttle valve 6 in series with the pump 5 is provided, the burden torque of the motor 4 can be changed. Of the present invention is not lost, and the variable throttle valve 6 is eliminated and only the variable throttle valve 7 arranged in parallel with the pump 5 is provided. Since the rotational speed of the motor 4 can be changed, the intersection of the rotational speed of the motor 4 and the burden torque can be kept within the regeneration region or the outputable torque range, and the effect of the present invention is not lost. As described above, the variable throttle valve 7 is arranged in parallel with the variable throttle valve 6 and the pump 5. However, the variable throttle valve 7 is arranged in series with respect to the variable throttle valve 6 and is parallel with only the pump 5. Arrangement Even, the point of intersection of the rotational speed and the load torque of the motor 4 can be accommodated in the regeneration region and possible output torque range, the effect of the present invention is not lost.

  Further, although the arrangement relationship between the pump 5 and the variable throttle valve 6 is shown, the pump 5 may be arranged on either side of the pressure chamber R1 or the pressure chamber R2. Further, any fluid such as oil, water, aqueous solution, gas or the like may be used as the fluid filled in the cylinder 1.

  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 conceptual diagram of the cylinder apparatus in one Embodiment. It is the model figure which showed the relationship between the flow volume and differential pressure | voltage of the cylinder apparatus in one Embodiment. It is the graph which made the rotation speed of a motor respond | correspond to the passage flow rate of a pump, and made it correspond to the differential pressure | voltage (pressure loss) when a fluid passes a pump with the torque of a motor. It is a figure which shows the output possible torque range of the motor in a braking area | region. It is a figure which shows the regeneration area | region of a motor. It is a figure which shows the relationship between the torque of a motor, and a regenerative current value.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder 2 Piston 3 Flow path 4 Motor 5 Pump 6,7 Variable throttle valve 8 Rod 9 Detour 10 Control apparatus 11 Sensor C Cylinder apparatus R1, R2 Pressure chamber

Claims (8)

A cylinder, a piston that is movably inserted into the cylinder and divides the inside of the cylinder into two pressure chambers, a flow path that communicates the two pressure chambers, and a midway in the flow path that is driven by a motor A cylinder apparatus comprising a bidirectional discharge type pump, wherein a variable throttle valve is provided in the middle of the flow path in parallel or in series with the pump. A cylinder, a piston that is movably inserted into the cylinder and divides the inside of the cylinder into two pressure chambers, a flow path that communicates the two pressure chambers, and a midway in the flow path that is driven by a motor A cylinder device comprising a bidirectional discharge type pump, wherein a variable throttle valve is provided in parallel and in series with the pump in the middle of a flow path. 3. The cylinder device according to claim 1, wherein when the motor is used in a braking region, the rotational speed of the motor and / or the torque to be borne by the motor are controlled by controlling the variable throttle valve. . 4. The variable throttle valve according to claim 1, wherein when the motor is used in a braking region, the variable throttle valve is controlled so that a torque to be borne by the motor falls within a torque output possible range of the motor. Cylinder device. The cylinder device according to any one of claims 1 to 4, wherein the variable throttle valve is controlled so as to increase the regeneration efficiency of the motor when the motor is used in a braking region. The variable throttle valve is controlled so that the regenerative current value of the motor is 50% or more of the maximum regenerative current value when the motor is used in a braking region. Cylinder device. The cylinder device according to any one of claims 1 to 6, wherein the variable throttle valve is controlled so that the regenerative current value of the motor becomes maximum when the motor is used in a braking region. It has a map of rotation speed and torque that maximizes the regenerative current value of the motor, and controls the variable throttle valve so that the regenerative current value of the motor is maximized when the motor is used in the braking region. The cylinder device according to claim 7.

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