JP2010071450A - Fluid pressure circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the adoption of an expensive configuration in the realization thereof while enabling the control of whether or not the expansion and contraction of the expansion and contraction is possible and the generation of the optimum damping force at the time of expansion and contraction of the expansion and contraction.
SOLUTION: Attenuating means 2 disposed in a flow path L connecting an expansion body 1 and a reservoir tank T and having a predetermined attenuating action when a working fluid passes, and disposed upstream of the attenuating means 2. And a lock mechanism 3 that enables opening and closing of the flow path l, and a lock valve 31 that opens and closes the flow path L when the lock mechanism 3 is operated, and an external signal connected to the lock valve 31. In a fluid pressure circuit having a switching valve 32 that enables or disables the operation of the lock valve 31 at the time of input or release, an external signal input to the switch valve 32 is induced from the upstream side of the lock mechanism 3. The pilot pressure is made.
[Selection] Figure 2

Description

  The present invention relates to a fluid pressure circuit, and more particularly, to an improvement in a fluid pressure circuit suitable for application to a seismic isolation device having a telescopic body that performs a damping action or a large-sized device.

  As a fluid pressure circuit suitable for application to a seismic isolation device having a telescopic body having a damping action or a large-scale device, various proposals have been made so far. For example, Patent Document 1 discloses a ball isolator constituting a seismic isolation device. The proposal which enables the expansion-contraction of expansion bodies, such as a hydraulic cylinder paralleled with seismic isolation bearings, etc., and the damping action accompanying expansion / contraction of this expansion-contraction body is disclosed.

  In other words, the fluid pressure circuit disclosed in this document has a damping means as a damping valve in a flow path connecting the expansion and contraction body and the reservoir tank, and this damping means is used when hydraulic oil from the expansion and contraction body passes. Realizes a damping action that suppresses expansion and contraction of the elastic body.

  On the other hand, this fluid pressure circuit has a lock mechanism that is disposed in the upstream side of the damping means and selects whether or not the damping means can be operated. It has a lock valve that opens and closes the flow path, and a switching valve that is connected to the lock valve and selects whether the lock valve can be operated.

  In this fluid pressure circuit, the switching valve in the lock mechanism is a solenoid valve that is a normally closed type on / off valve, and is switched to a communication position (on state) when energized based on signals from various detection means. The on-operation of the lock valve is allowed, and when the energization is released, the lock valve returns to the shut-off position (off state) to turn off the lock valve, and this lock valve is maintained in the locked state.

  Therefore, in the fluid pressure circuit disclosed in this document, for example, when the expansion and contraction body parallel to the seismic isolation bearing expands and contracts with a minute stroke by the wind, the lock valve in the lock mechanism is maintained in the locked state, Prevent expansion and contraction of the elastic body.

  On the other hand, when the expansion and contraction body expands and contracts with a large stroke due to shaking due to an earthquake, the switching valve in the lock mechanism is energized and turned on, and the lock valve in the lock mechanism is turned on (opening operation) to operate the damping means The expansion / contraction of the expansion / contraction body is suppressed by the generation of damping force.

  When the expansion and contraction of the expansion / contraction body due to the shaking of the earthquake is suppressed and settled, the switching valve returns to the OFF state by releasing the signal such as passing through the timer, so the lock valve is turned OFF (closing operation) and locked Maintained.

Incidentally, in the fluid pressure circuit disclosed in the above literature, the expansion / contraction stroke of the expansion / contraction body is extremely large. Therefore, when the amount of hydraulic oil passing through the lock valve and the damping means in the lock mechanism becomes excessive, the lock mechanism The relief valve disposed on the upstream side of the cylinder is actuated, and hydraulic oil from the excessive expansion / contraction body is discharged to the reservoir tank.
Japanese Patent Laying-Open No. 2005-351320 (see abstract, paragraphs 0007 and 0017 in the specification, FIG. 1)

  However, in the fluid pressure circuit disclosed in the above-mentioned literature, there is basically no defect in the performance of the predetermined lock function and the attenuation function, but it is pointed out that there is a minor problem in implementation. There is a possibility that.

  That is, in the proposal of the above-mentioned literature disclosure, the switching valve in the lock mechanism is a solenoid valve that switches to an on state when energized based on signals from various detection means and returns to an off state when energization is released.

  Therefore, when this fluid pressure circuit is used, in order to ensure the proper operation of the lock mechanism, it is essential that various detection means be disposed on the telescopic body and its periphery. Compared to the case where it is not necessary, there is a concern that the configuration embodying the fluid pressure circuit may be expensive.

  In the above fluid pressure circuit, since the switching valve is composed of a solenoid valve, maintenance such as replacement of the electrical parts in advance is performed so that the switching valve does not become inoperable due to aging of the electrical parts. There is a defect that makes it indispensable and does not facilitate performance guarantee.

  The present invention has been developed in view of the above-described circumstances. The object of the present invention is to control whether or not the stretchable body can be stretched and to generate an optimum damping force when the stretchable body is stretched. Needless to say, it is to provide a fluid pressure circuit which can avoid the use of an expensive configuration in its realization and is optimal for expecting improvement in its versatility.

  In order to achieve the above-described object, the configuration of the fluid pressure circuit according to the present invention is basically arranged in a flow path connecting the expansion and contraction body and the reservoir tank, and has a predetermined damping action when the working fluid passes. A locking mechanism that is disposed upstream of the damping means and enables the opening and closing of the flow path, and a lock valve that opens and closes the flow path when the locking mechanism is activated, An external signal input to the switching valve in a fluid pressure circuit connected to the lock valve and having a switching valve that enables or disables the operation of the lock valve when an external signal is input or released Is a pilot pressure derived from the upstream side of the lock valve.

  Therefore, according to the present invention, the damping means disposed in the flow path connecting the expansion body and the reservoir tank and having a predetermined damping action when the working fluid passes, and disposed upstream of the damping means. A lock mechanism that enables opening and closing of the flow path, and a lock valve that opens and closes the flow path when the lock mechanism is activated, and is connected to the lock valve when an external signal is input or released In the fluid pressure circuit having a switching valve that enables or disables the operation of the lock valve, an external signal input to the switching valve is a pilot pressure induced from the upstream side of the lock mechanism. Compared to the case where the external signal to which the switching valve is input is an electrical signal, it is possible to avoid an increase in the size of the switching valve and the use of costly parts.

  In addition, since the switching valve converts the pilot pressure to an external signal, there is no need to provide various detection means for outputting electrical signals to the telescopic body and its surroundings, and the detection results from the detection means are electrically output. It is not necessary to provide a control means for performing arithmetic processing or the like for obtaining a target signal, and an improvement in versatility can be expected without making the configuration embodying the fluid pressure circuit expensive.

  Hereinafter, the present invention will be described based on the illustrated embodiment. A fluid pressure circuit according to the present invention is, for example, a seismic isolation device disposed between a structure A and a ground G as shown in FIG. It is suitable for the realization to the elastic body 1 which comprises.

  The seismic isolation device has a seismic isolation support B composed of ball isolators arranged in parallel with the above-described telescopic body 1, and this seismic isolation support B is, for example, when the ground G rolls due to an earthquake. Prevent the roll of ground G from propagating to structure A.

  And the expansion-contraction body 1 carries out the attenuation | damping action for quickly calming down the rolling in this structure A, for example, when the structure A rolls due to the rolling of the ground G by an earthquake.

  From this point of view, this seismic isolation bearing B is not shown in the figure, but it is not shown, but as long as the seismic isolation function is exhibited, the base isolation structure consisting of laminated rubber columns is used. Good.

  Incidentally, although the fluid pressure circuit according to the present invention is not shown in the configuration, the above-mentioned telescopic body 1 is installed on the floor or the like and connected to a large device, and may realize the damping action in this large device. good.

  The telescopic body 1 is composed of, for example, a hydraulic cylinder that is a liquid pressure cylinder, and as shown in FIG. 2, the hydraulic cylinder includes a cylinder body 1a and a rod body 1b that is connected to the cylinder body 1a so as to be capable of protruding and retracting. The rod body 1b is slidably accommodated in the cylinder body 1a while being connected to the rod body 1b. The cylinder body 1a includes a rod body chamber R1 and a piston body 1c that defines a piston chamber R2.

  The rod-side chamber R1 and the piston-side chamber R2 in the telescopic body 1 serving as a hydraulic cylinder can communicate with each other via a communication path 1d disposed outside the cylinder body 1a. The check valve 1e disposed in 1d allows the piston side chamber R2 to communicate with the rod side chamber R1, while blocking the communication of the rod side chamber R1 with the opposite flow to the piston side chamber R2 in the opposite direction. Uniflow type is set.

  In the telescopic body 1, the hydraulic oil from the reservoir tank T is allowed to flow into the piston side chamber R2 through the suction path 1f. The suction path 1f is connected to the piston side chamber R2 side. A check valve 1g for preventing the backflow of the hydraulic oil to the reservoir tank T is provided.

  Therefore, in the telescopic body 1 described above, the hydraulic oil in the piston side chamber R2 that is prevented from flowing out into the reservoir tank T by the check valve 1g during the contraction operation in which the rod body 1b is immersed in the cylinder body 1a is connected. It flows into the passage 1d, flows into the rod side chamber R1 in the cylinder body 1a via the check valve 1e disposed in the communication passage 1d, and enters the later-described main flow path L constituting the fluid pressure circuit from the rod side chamber R1. Inflow.

  Contrary to the above, during the extension operation in which the rod body 1b protrudes from the cylinder body 1a, the hydraulic oil from the rod side chamber R1 contracted by the movement of the piston body 1c is opposite to the check valve 1e of the communication path 1d. Since the flow into the piston side chamber R2 is blocked, the flow flows into the main flow path L.

  The piston side chamber R2 that is expanded by the movement of the piston body 1c is replenished with working oil from the reservoir tank T via the suction flow path 1f and the check valve 1g in the flow path 1f.

  In addition, although said expansion-contraction body 1 consists of hydraulic cylinders, therefore, it uses hydraulic oil for a working fluid, However, As long as it is set as a hydraulic cylinder, you may use other fluids, for example, rust etc. If there is no adverse effect, water may be used as the working fluid.

  As shown in the figure, the telescopic body 1 is composed of a hydraulic cylinder. However, as long as it expands and contracts due to the inflow and outflow of fluid, there is no problem such as strength when applied to a seismic isolation device or other equipment. For example, in addition to the hydraulic cylinder, a container that can be expanded and contracted by flowing in and out of the fluid may be used.

  By the way, the fluid pressure circuit is disposed in a main flow path L that connects the rod side chamber R1 and the reservoir tank T in the expansion / contraction body 1, and is a damping means that performs a predetermined damping action when hydraulic fluid as working fluid passes. 2 and a lock mechanism 3 that is disposed on the upstream side of the attenuating means 2 and that allows the flow path L to be opened and closed.

  The lock mechanism 3 is connected to the lock valve 31 that opens and closes the flow path L during operation, and enables or disables the operation of the lock valve 31 when an external signal is input or released. And a switching valve 32.

  First, the attenuating means 2 basically has a predetermined attenuating action when hydraulic fluid passes through. Therefore, for the specific configuration, an arbitrary configuration can be selected. It consists of a variable damping valve that can embody a damping action according to the hydraulic conditions in the main flow path L.

  In the damping means 2 composed of this variable damping valve, the damping characteristic can be changed according to the expansion / contraction speed of the expansion / contraction body 1, so that the optimum attenuation characteristic can be obtained for the seismic isolation device to which the expansion / contraction body 1 is applied. This is advantageous.

  Although a simple throttle valve may be used as the attenuating means 2, it is arranged in parallel between the telescopic body 1 and the reservoir tank T as in the case of an optimum embodiment of the present invention described later shown in FIG. When the plurality of flow paths L1, L2, L3, and L4 have the damping means 2 and the lock valve 31 in the lock mechanism 3, respectively, it is suitable for use when each damping means 2 is set to exhibit different damping characteristics. I will.

  Next, the lock valve 31 specifically has a poppet 31a as a valve body, and the poppet 31a is urged by a biasing means 31c to a valve seat 31b formed in the flow path L. A passage 31d is provided for guiding the hydraulic pressure upstream of the valve seat 31b to the back side of the poppet 31a while seated, and the passage 31d has a throttle 31e, which is the right end face side in FIG. The back side having the biasing means 31c is communicated with a switching valve 32 described later.

  Therefore, the lock valve 31 closes the flow path L when the poppet 31a is in the advanced state and is seated on the valve seat 31b, as shown in the figure. The hydraulic oil from the side chamber R1 cannot flow out to the later-described damping means 2 side, that is, the reservoir tank T via the flow path L, and as a result, the expansion / contraction body 1 is maintained in a lock state where it cannot expand and contract.

  The lock valve 31 opens the flow path L when the poppet 31a moves backward in the drawing to overcome the urging force of the urging spring 31c (not shown), and therefore expands and contracts. The hydraulic oil from the rod side chamber R1 in the body 1 is allowed to flow out to the reservoir tank T through the flow path L and the damping means 2, and at this time, the damping means 2 realizes a predetermined damping action by the passage of the hydraulic oil. Turn into.

  In this embodiment, the lock valve 31 has a poppet 31a. However, considering that the poppet 31a functions, instead of this, a spool may be selected as a valve body, although not shown. .

  In addition, as described above, the lock valve 31 closes the flow path L when moving forward and opens the flow path L when moving backward. However, from the point of the present invention, instead of this, the flow path L when moving forward. L may be opened, and the flow path L may be closed when retreating.

  The switching valve 32 is composed of a pilot switching valve, as shown in the figure, and is switched at the time of supplying pilot pressure as an external signal to allow communication with the reservoir tank T on the back side of the poppet 31a in the lock valve 31. 32a, and a shutoff position 32b that is maintained before the supply of the pilot pressure, which is the time when the pilot pressure that is an external signal is eliminated, and prevents the lock valve 31 from communicating with the reservoir tank T on the back side of the poppet 31a. ing.

  In the switching valve 32, the communication position 32a and the shut-off position 32b are maintained by a detent mechanism 32c incorporated in the switching valve 32. A handle 32d as an input means for operating force is provided, and a return operation from the communication position 32a to the shut-off position 32b is enabled by manual operation on the handle 32d.

  Therefore, in the switching valve 32, as shown in the figure, when the switch valve 32 is maintained at the shut-off position 32b, the communication with the reservoir tank T on the back side of the poppet 31a in the lock valve 31 is shut off. The lock valve 31 is prevented from opening.

  Although not shown, the switching valve 32 is supplied to a reservoir tank T on the back side of the poppet 31a of the lock valve 31 when the pilot valve is switched to the communication position 32a in response to the supply of pilot pressure described later. The communication is allowed and the opening operation of the lock valve 31 is allowed.

  In addition, since the switching valve 32 has the detent mechanism 32c and can maintain the communication position 32a and the cutoff position 32b, the pilot pressure is eliminated, and therefore the switching valve 32 is switched to the cutoff position 32b. Even if the situation can be returned, it does not immediately return to the blocking position 32b.

  As a result, for example, the switching valve 32 is switched to the communication position 32a. Therefore, even if the expansion / contraction of the expansion / contraction body 1 is subdued after the dredging, the switching valve 32 does not immediately return to the cutoff position 32b. That's enough.

  That is, for example, the structure A rolls due to an earthquake, and at this time, the switching valve 32 is switched to the communication position 32a. Therefore, the expansion and contraction of the expansion / contraction body 1 is allowed, and then the earthquake is stopped and the structure A rolls. Therefore, when the expansion / contraction of the expansion / contraction body 1 is settled, it can be said that, for example, it is unlikely that the switching valve 31 immediately returns to the cutoff position 32b by diving immediately under the floor of the structure A.

  In other words, after the shaking of the structure A due to the earthquake has stopped, it will be checked whether there is any change in the structure A, but in the seismic isolation device, the switching valve 32 must be immediately returned to the cutoff position 32b. It can be said that there are few.

  From the above, as in the present invention, in the switching valve 32, the return operation to the shut-off position 32b is sufficient by the manual operation using the handle 32d, and when returning to the shut-off position 32b by the handle operation. In other words, as compared with the case of automatically returning to the shut-off position 32b, it can be said that the configuration of the switching valve 32 does not have to be unnecessarily complicated and is advantageous in terms of component costs.

  In the switching valve 32 described above, it can be switched to the communication position 32a when the pilot pressure as an external signal is supplied, and can return to the cutoff position 32b when the pilot pressure as an external signal is eliminated. In this case, instead of this, it is possible to switch to the communication position 32a when the pilot pressure is released and return to the cutoff position 32b when the pilot pressure is supplied.

  On the other hand, as described above, in the present invention, a pilot pressure is input to the switching valve 32 as an external signal, and this pilot pressure is shown in the figure and constitutes the lock mechanism 3 described above. It is guided from the upstream side of the lock valve 31 through the pilot flow path 4.

  That is, the pilot flow path 4 has a base valve connected to the main flow path L described above and has a sequence valve 41 for setting a pilot pressure in the middle, and a so-called reverse flow in the pilot flow path 4, that is, the telescopic body 1. A check valve 42 that enables stable supply of hydraulic pressure to the pilot flow path 4 from the side is provided, and pilot pressure is induced in the switching valve 32.

  Incidentally, the illustrated pilot flow path 4 has a manual valve 43 that can open and close the pilot flow path 4 before it is connected to the reservoir tank T. The manual valve 43 has a pressure in the pilot flow path 4. In the operation of avoiding the beat, that is, when the switching valve 32 is returned to the cutoff position 32b, the pilot pressure remains in the pilot flow path 4, and therefore the return operation to the cutoff position 32b cannot be realized smoothly. Allows pressure relief to avoid.

  Therefore, in the manual valve 43, as described above, when the actual operation of the switching valve 32 is taken into account, that is, the operating oil leaks over time in the switching valve 32 and the pilot pressure is eliminated. In consideration of the fact, it can be said that the arrangement may be omitted. However, in the illustrated case, if the manual valve 43 is omitted, the supply of the pilot pressure to the switching valve 32 becomes impossible.

  Therefore, in this pilot flow path 4, although not shown, a throttle instead of the manual valve 43 may be provided to ensure the supply of the pilot pressure to the switching valve 32. After connecting to the valve 32, a connecting drain flow path connected to the reservoir tank T may be separately connected to the switching valve 32, and the manual valve 43 may be provided in the drain flow path.

  On the other hand, in the fluid pressure circuit according to the present invention, a relief channel 5 for connecting the expansion / contraction body 1 and the reservoir tank T is provided, and a relief for avoiding an excessive hydraulic pressure action in the expansion / contraction body 1 in the relief channel 5. A valve 51 is provided.

  Therefore, in the fluid pressure circuit in which the relief valve 51 is provided in the relief flow path 5, it is possible to avoid an excessive hydraulic pressure action in the telescopic body 1. Even in such a case, the stretchable body 1 can be expanded and contracted without causing leakage of hydraulic oil, and therefore, it is possible to realize earthquake resistance depending on the strength of the structure A.

  FIG. 3 shows another embodiment of the present invention. In this embodiment, a plurality of channels L1, L2, L3, and L4 are provided to connect the elastic body 1 and the reservoir tank T. In addition, a damping valve 2 and a lock valve 31 in the lock mechanism 3 are disposed in each flow path L1, L2, L3, L4, while a single switching valve 32 is connected to each lock valve 31. The pilot pressure induced from the upstream side of each lock mechanism 3 is input to the switching valve 32 as an external signal.

  In FIG. 3, where the configuration is the same as that shown in FIG. 2, only the same reference numerals are given in the drawing, and the description is omitted unless necessary. .

  Therefore, in the case of this embodiment, first, since there are a plurality of flow paths, the flow rate of the working fluid from the expansion body 1 toward the reservoir tank T can be increased, and the damping action by the damping means 2 is flexible. It becomes possible to have.

  In this case, each attenuation means 2 may have the same configuration, and thus may exhibit the same attenuation characteristics, and each attenuation means 2 may have a different configuration, and thus may exhibit different attenuation characteristics. .

  In the case of this embodiment, the lock valve 31 in the lock mechanism 3 for selecting whether the operation of the damping means 2 is enabled or not is provided corresponding to each damping means 2. In the so-called damping element, it is possible to avoid inconvenience that the damping action is not realized at all even in the case of failure such as malfunction.

  Even in this embodiment, the switching valve 32 can be made larger and costly parts can be avoided as compared with the case where the switching valve 32 is composed of a solenoid valve that uses an electrical signal as an external signal. Since the switching valve 32 converts the pilot pressure to an external signal, there is no need to provide various detection means for outputting an electrical signal to the telescopic body 1 and its periphery, and the detection result from the detection means is electrically It is not necessary to provide a control means for performing arithmetic processing for making a signal.

  In the illustrated embodiment, the lock valve 31 has the same configuration, but the operation timing of each switching valve 32 may be changed by providing a variable throttle in the flow path for inducing the pilot pressure. .

  As described above, in the seismic isolation device, the expansion body 1 is normally maintained in a locked state in which expansion and contraction is prevented. However, the present invention is intended to enable expansion and contraction of the expansion body 1. Since the operation of the lock valve 31 in the lock mechanism 3 to be performed is based on the switching valve 32 and the operation of the switching valve 32 is based on the pilot pressure as an external signal, from this point of view, the telescopic body 1 is normally The locking valve 31 may be instantaneously switched to the locked state by the input of the shaking of the earthquake, and the operation of the switching valve 32 may be enabled.

It is a figure which shows in principle the seismic isolation apparatus which has an expansion-contraction body by which the fluid pressure circuit of this invention is embodied. It is a circuit diagram which shows the fluid pressure circuit by one Embodiment of this invention with an expansion-contraction body. It is a circuit diagram which shows the fluid pressure circuit in other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Telescopic body 2 Damping means 3 Lock mechanism 4 Pilot flow path 5 Relief flow path 31 Lock valve 31a Poppet as valve body 32 Switching valve 32a Communication position 32b Shut-off position 32c Detent mechanism 32d Handle as input means 41 Sequence valve 51 Relief valve L, L1, L2, L3, L4 Flow path R1 Rod side chamber R2 Piston side chamber T Reservoir tank

Claims (8)

Attenuating means disposed in a flow path connecting the extendable body and the reservoir tank and having a predetermined attenuating action when the working fluid passes, and disposed on the upstream side of the attenuating means for opening and closing the flow path. And a lock valve that opens and closes the flow path when the lock mechanism is activated, and the lock valve can be operated when an external signal is input or released by being connected to the lock valve. A fluid pressure circuit having a switching valve that enables the external signal input to the switching valve to be a pilot pressure induced from the upstream side of the lock valve. Fluid pressure circuit. The fluid pressure circuit according to claim 1, wherein the pilot pressure is set by a sequence valve disposed in a pilot flow path having a base end connected to the upstream side of the lock valve. 3. The switching valve according to claim 1, wherein the switching valve is switched when the pilot pressure is supplied and when the pilot pressure is supplied and has a communication position and a cutoff position that enable or disable the operation of the lock valve. Fluid pressure circuit. The switching valve is provided with a detent mechanism, and the detent mechanism can maintain the shut-off position and the communication position of the switching valve when the pilot pressure is supplied or canceled. Item 4. The fluid pressure circuit according to Item 3. The switching valve has input means for allowing external operation, and the input means changes from the shut-off position or communication position of the switch valve to the opposite communication position or shut-off position when the pilot pressure is supplied or canceled. 5. The fluid pressure circuit according to claim 1, wherein the fluid pressure circuit can be switched. 2. The valve body according to claim 1, wherein the lock valve has a valve body that opens and closes the flow path when moving forward and backward while being formed of a poppet or a spool, and the valve body is advanced and retracted by switching the acting force acting on the back surface of the valve body. , Claim 2, Claim 3, Claim 4 or Claim 5. A relief flow path for connecting the expansion body and the reservoir tank is provided, and a relief valve for avoiding an excessive hydraulic action in the expansion body is provided in the relief flow path. A fluid pressure circuit according to claim 3, claim 4, claim 5, or claim 6. A plurality of the flow paths connecting the expansion and contraction body and the reservoir tank are provided, and the attenuation means and the lock valve are disposed in each of the plurality of flow paths. The lock valve is connected to the switching valve, and the pilot pressure is input to the switching valve as an external signal. Claims 1, 2, 3, 4, 4, and 5 The fluid pressure circuit according to claim 6 or 7.

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