Hydraulic damper, hydraulic adjustment device, and method for controlling a hydraulic damper

Abstract

To improve energy absorption while simplifying the structure of a hydraulic damper. [Solution] The hydraulic adjustment module 3 of the hydraulic damper 1 has an accumulator 38 for releasing the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22, a reciprocal opening / closing control valve that switches between open to allow the movement of hydraulic oil from the first hydraulic chamber 21 to the second hydraulic chamber 22 and from the second hydraulic chamber 22 to the first hydraulic chamber 21 and closed to prohibit the movement of the hydraulic oil, a first opening / closing control valve that switches between open to allow the movement of hydraulic oil from the first hydraulic chamber 21 to the accumulator 38 and closed to prohibit the movement of hydraulic oil, and a second opening / closing control valve 32 that switches between open to allow the movement of hydraulic oil from the second hydraulic chamber 22 to the accumulator 38 and closed to prohibit the movement of hydraulic oil.

Description

[Technical field]

[0001] The present invention relates to a hydraulic damper, a hydraulic regulator, and a method for controlling a hydraulic damper. [Background technology]

[0002] Hydraulic dampers are used as vibration control devices to reduce the shaking of buildings. A typical hydraulic damper is equipped with an adjustment valve to keep the damping constant constant. Hydraulic dampers with improved performance to keep the damping constant constant are disclosed in Patent Documents 1 to 3. The hydraulic dampers disclosed in Patent Documents 1 to 3 are equipped with a cylinder, a piston that reciprocates inside the cylinder, hydraulic chambers provided on both sides of the piston, and an opening / closing control valve provided in a flow path connecting both hydraulic chambers. The hydraulic dampers disclosed in Patent Documents 1 and 2 improve the energy absorption amount of the hydraulic damper by controlling the opening and closing of the opening / closing control valve. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3397199 [Patent Document 2] Patent No. 4358091 [Patent Document 3] Patent No. 6000872 Summary of the Invention [Problem to be solved by the invention]

[0004] The hydraulic damper disclosed in Patent Document 3 aims to further improve the amount of energy absorption compared to the hydraulic dampers disclosed in Patent Documents 1 and 2 by diverting the regenerated energy to reduce sway. For this reason, the hydraulic damper disclosed in Patent Document 3 further includes an auxiliary hydraulic tank in addition to a cylinder, a piston, and an opening / closing control valve. As a result, the hydraulic damper disclosed in Patent Document 3 has a more complicated mechanism than hydraulic dampers that do not include an auxiliary hydraulic tank, such as the hydraulic dampers disclosed in Patent Documents 1 and 2, and therefore the cost may increase. Furthermore, the hydraulic damper disclosed in Patent Document 3 requires a relatively large auxiliary hydraulic tank, which may limit the location where the hydraulic damper can be installed.

[0005] Therefore, an object of the present invention is to provide a hydraulic damper, a hydraulic adjustment device, and a method for controlling a hydraulic damper that can improve the amount of energy absorption while simplifying the structure of the hydraulic damper. [Means for solving the problem]

[0006] One aspect of the present invention is a hydraulic device comprising: [1] "a cylinder having an internal space filled with hydraulic oil; a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder; and a hydraulic pressure adjustment unit connected to each of the first hydraulic chamber and the second hydraulic chamber, the hydraulic pressure adjustment unit being connected to the first hydraulic chamber via a first open flow path and to the second hydraulic chamber via a second open flow path ... the hydraulic damper having: a reciprocal opening / closing control valve provided in the first release flow path and switching between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil; a first opening / closing control valve provided in the first release flow path and switching between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the movement of the hydraulic oil; and a second opening / closing control valve provided in the second release flow path and switching between an open state to permit the movement of the hydraulic oil from the second hydraulic chamber to the pressure release portion and a closed state to prohibit the movement of the hydraulic oil.

[0007] The hydraulic adjustment unit of the hydraulic damper in one embodiment has a mutual opening / closing control valve, a first opening / closing control valve, and a second opening / closing control valve. In this configuration, for example, when the hydraulic pressure in the first hydraulic chamber on the high pressure side begins to decrease, the mutual opening / closing control valve can be opened. As a result, the hydraulic oil in the first hydraulic chamber on the high pressure side moves to the second hydraulic chamber on the low pressure side, so that a part of the energy stored in the first hydraulic chamber can be directly moved to the second hydraulic chamber. As a result, since there is no need to provide an additional hydraulic circuit element for regenerating the energy stored in the first hydraulic chamber, the configuration of the hydraulic circuit can be simplified. Furthermore, the hydraulic adjustment unit can lower the pressure of the first hydraulic chamber, which was on the high pressure side, below the pressure of the second hydraulic chamber by opening the first opening / closing control valve after closing the mutual opening / closing control valve. The resulting pressure difference between the first hydraulic chamber and the second hydraulic chamber contributes to further increasing the amount of energy absorbed by the earthquake acting on the building. In other words, it is possible to improve the amount of energy absorbed by providing an offset to the load of the hydraulic damper with a simple configuration.

[0008] One aspect of the present invention may be the hydraulic damper according to [1] above, [2] "wherein the hydraulic pressure adjustment unit alternates between a first hydraulic circuit configuration in which the mutual on-off control valve is closed, the first on-off control valve is closed, and the second on-off control valve is closed, a second hydraulic circuit configuration in which the mutual on-off control valve is open, the first on-off control valve is closed, and the second on-off control valve is closed, and a third hydraulic circuit configuration in which the mutual on-off control valve is closed, one of the first on-off control valve and the second on-off control valve is open, and the other is closed." Even with this configuration, the energy absorption amount can be appropriately improved.

[0009] One aspect of the present invention may be the hydraulic damper according to the above-mentioned [2], in which the hydraulic pressure adjustment unit switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration in this order. Even with this configuration, the amount of energy absorption can be appropriately improved.

[0010] One aspect of the present invention may be the hydraulic damper according to [4] or [3] above, wherein the hydraulic pressure adjustment unit switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration based on the pressure in the first hydraulic chamber and the pressure in the second hydraulic chamber. In this case, the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration can be switched between without being based on the moving direction of a piston, for example.

[0011] One aspect of the present invention may be the hydraulic damper according to [5] above, wherein the hydraulic adjustment unit is configured to use the first hydraulic circuit configuration when the pressure in the first hydraulic chamber increases in response to the movement of the piston, and is configured to switch from the first hydraulic circuit configuration to the second hydraulic circuit configuration in which the reciprocal on-off control valve is open and the first on-off control valve and the second on-off control valve are closed when the direction of movement of the piston is reversed, and is configured to use the third hydraulic circuit configuration in which the first on-off control valve is open and the second on-off control valve is closed when the pressure difference between the pressure in the first hydraulic chamber and the pressure in the second hydraulic chamber becomes smaller than a threshold value. Even with this configuration, the amount of energy absorption can be appropriately improved.

[0012] Another aspect of the present invention is [6] "a hydraulic pressure adjusting device for a hydraulic damper, comprising: a cylinder having an internal space filled with hydraulic oil; and a piston arranged inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder, the piston including a pressure release section connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber; and a pressure release section provided in a mutual flow path having one end connected to the first hydraulic chamber and the other end connected to the second hydraulic chamber, the pressure release section being connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber. a reciprocal opening / closing control valve which alternately switches between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil, a first opening / closing control valve which is provided in the first release flow path and alternately switches between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the movement of the hydraulic oil, and a second opening / closing control valve which is provided in the second release flow path and alternately switches between an open state to permit the movement of the hydraulic oil from the second hydraulic chamber to the pressure release portion and a closed state to prohibit the movement of the hydraulic oil. This hydraulic adjustment device also makes it possible to improve the energy absorption amount while simplifying the structure of the hydraulic damper.

[0013] Yet another embodiment of the present invention is [7] "a method for controlling a hydraulic damper including a cylinder having an internal space filled with hydraulic oil, and a piston arranged inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder, the method comprising: a first step of prohibiting the outflow of the hydraulic oil from the first hydraulic chamber and the second hydraulic chamber when the pressure of the first hydraulic chamber increases in response to the movement of the piston; a second step of allowing the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber when the direction of movement of the piston is reversed; and a third step of prohibiting the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and releasing the pressure of the first hydraulic chamber when the pressure difference between the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber becomes smaller than a threshold value." This method for controlling a hydraulic damper also simplifies the structure of the hydraulic damper while improving the energy absorption amount. Effect of the Invention

[0014] According to the present invention, it is possible to provide a hydraulic damper, a hydraulic adjustment device, and a method for controlling a hydraulic damper that can improve the amount of energy absorption while simplifying the structure of the hydraulic damper. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing an example of a state in which a hydraulic damper according to an embodiment is installed in a building. [Diagram 2] FIG. 2 is a diagram showing an example of a hydraulic circuit of the hydraulic damper shown in FIG. [Diagram 3] FIG. 3 is a diagram showing an example of a specific cross-sectional structure of the hydraulic damper shown in FIG. [Figure 4]FIG. 4(a) is a diagram showing a building structural part and a vibration control structural part in a first state. FIG. 4(b) is a diagram showing a hydraulic damper in a first state. FIG. 4(c) is a mechanical model showing a hydraulic damper in a first state. FIG. 4(d) is a diagram showing a building structural part and a vibration control structural part in a second state. FIG. 4(e) is a diagram showing a hydraulic damper in a second state. FIG. 4(f) is a mechanical model showing a hydraulic damper in a second state. FIG. 4(g) is a diagram showing a building structural part and a vibration control structural part in a third state. FIG. 4(h) is a diagram showing a hydraulic damper in a third state. FIG. 4(i) is a mechanical model showing a hydraulic damper in a third state. [Diagram 5] Fig. 5(a) is a diagram showing a schematic diagram of the building structural part and the vibration control structural part in the fourth state. Fig. 5(b) is a diagram showing a schematic diagram of the hydraulic damper in the fourth state. Fig. 5(c) is a mechanical model showing the hydraulic damper in the fourth state. Fig. 5(d) is a diagram showing a schematic diagram of the building structural part and the vibration control structural part in the fifth state. Fig. 5(e) is a diagram showing a schematic diagram of the hydraulic damper in the fifth state. Fig. 5(f) is a mechanical model showing the hydraulic damper in the fifth state. [Figure 6] 6(a), 6(b) and 6(c) are graphs showing the relationship between the displacement occurring in the body connection and the internal load. [Figure 7] FIG. 7 is a flow chart illustrating an example of a method for controlling a hydraulic damper. [Figure 8] FIG. 8 is a diagram showing a hydraulic circuit of the hydraulic damper according to the first embodiment. [Figure 9] FIG. 9 is a diagram showing a hydraulic circuit of the hydraulic damper according to the second embodiment. [Figure 10] FIG. 10 is a diagram showing a hydraulic circuit of a hydraulic damper according to the third embodiment. [Figure 11] FIG. 11 is a diagram showing a hydraulic circuit of a hydraulic damper according to the fourth embodiment. [Figure 12] FIG. 12 is a diagram showing a hydraulic circuit of a hydraulic damper according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted.

[0017] As shown in FIG. 1, the hydraulic damper 1 (oil damper) of the embodiment is applied to a building 100. The hydraulic damper 1 is installed, for example, on any floor (inter-floor) of the building 100. FIG. 1 shows a simplified view of a part of the building 100. The building 100 is composed of columns 101a and 101b provided in the vertical direction, and beams 102a and 102b that are suspended between the columns 101a and 101b. The upper end of the brace 103a is connected to the connection portion between the upper beam 102a and the column 101a. The portion where the upper beam 102a and the brace 103a are connected to each other is referred to as the building body connection portion 110c. Furthermore, the portion where the lower beam 102b and the column 101a are connected to each other is referred to as the building body connection portion 110d. The upper end of the brace 103b is connected to the connection portion between the beam 102a and the column 101b. The lower ends of the braces 103a and 103b are connected to each other. The portion where the lower ends of the braces 103a and 103b are connected to each other is referred to as the brace connection portion 103c. The hydraulic damper 1 is provided between the brace connection portion 103c and the column 101b. More specifically, the hydraulic damper 1 has a first end 1a connected to the brace connection portion 103c and a second end 1b connected to the column 101b. In the following description, the columns 101a, 101b and the beams 102a, 102b are collectively referred to as the building structural portion 110. Furthermore, the braces 103a, 103b and the hydraulic damper 1 are collectively referred to as the seismic control structural portion 120.

[0018] For example, when a building 100 shakes horizontally due to a vibration external force F100 such as an earthquake or wind, the horizontal position of the upper-story beam 102a shifts relative to the lower-story beam 102b (see FIG. 4(d)). The hydraulic damper 1 absorbs the energy that causes the horizontal shift. As a result, the horizontal shift that occurs in the building structural part 110 can be suppressed. The hydraulic damper 1 will be described in more detail below.

[0019] FIG. 2 is a diagram showing a schematic configuration of a hydraulic damper 1. FIG. 3 is a diagram showing an example of a specific configuration of the hydraulic damper 1 shown in FIG. 2. The hydraulic damper 1 has a damper module 2 and a hydraulic adjustment module 3 (hydraulic adjustment section, hydraulic adjustment device). The damper module 2 is provided with a first hydraulic chamber 21 and a second hydraulic chamber 22. The first hydraulic chamber 21 and the second hydraulic chamber 22 are filled with hydraulic oil 200. The hydraulic adjustment module 3 controls the internal pressure in the first hydraulic chamber 21 and the internal pressure in the second hydraulic chamber 22. By controlling this internal pressure, the damper module 2 can absorb energy due to an earthquake.

[0020] <Damper module 2> The damper module 2 has a cylinder 23, a piston 24, and a pair of piston rods 25a, 25b. The cylinder 23 is formed, for example, in a cylindrical shape. The cylinder 23 has an internal space 20 inside the cylinder 23. The internal space 20 is filled with hydraulic oil 200 for operating the hydraulic damper 1.

[0021] The piston 24 is disposed inside the cylinder 23. The piston 24 is formed in a disk shape, for example, when viewed from a direction along the central axis of the cylinder 23. The piston 24 divides the internal space 20 into a first hydraulic chamber 21 and a second hydraulic chamber 22. The piston 24 reciprocates inside the cylinder 23.

[0022] <Hydraulic adjustment module 3> The hydraulic pressure adjustment module 3 has several pipelines for moving the hydraulic oil 200, and several hydraulic circuit elements for switching between permission and prohibition of the movement of the hydraulic oil 200. Specifically, the hydraulic pressure adjustment module 3 has a first open flow path P1, a second open flow path P2, and a mutual flow path P3. Furthermore, the hydraulic pressure adjustment module 3 has a first opening / closing control valve 31, a second opening / closing control valve 32, and a mutual opening / closing control valve 33. Furthermore, the hydraulic pressure adjustment module 3 has an accumulator 38 (pressure release section) for adjusting the internal pressure of the damper module 2.

[0023] The first open flow path P1 connects the first hydraulic chamber 21 and the accumulator 38 to each other. In other words, the first open flow path P1 has a function of moving the hydraulic oil 200 from the first hydraulic chamber 21 to the accumulator 38, and a function of moving the hydraulic oil 200 from the accumulator 38 to the first hydraulic chamber 21. The second open flow path P2 connects the second hydraulic chamber 22 and the accumulator 38 to each other. In other words, the second open flow path P2 has a function of moving the hydraulic oil 200 from the second hydraulic chamber 22 to the accumulator 38, and a function of moving the hydraulic oil 200 from the accumulator 38 to the second hydraulic chamber 22.

[0024] In the example of FIG. 2, the first open flow path P1 includes a portion common to the second open flow path P2. This common portion is called a shared flow path portion Pc. A first end of the shared flow path portion Pc is connected to the accumulator 38. A first branch flow path portion P1a and a second branch flow path portion P2a are connected to a second end of the shared flow path portion Pc. An end of the first branch flow path portion P1a is connected to the first hydraulic chamber 21. An end of the second branch flow path portion P2a is connected to the second hydraulic chamber 22. Such a second end of the shared flow path portion Pc is called a shared connection point C1. That is, the first open flow path P1 includes the shared flow path portion Pc and the first branch flow path portion P1a. The second open flow path P2 includes the shared flow path portion Pc and the second branch flow path portion P2a.

[0025] The first branch flow path section P1a has a first end connected to the shared connection point C1 and a second end connected to the first hydraulic chamber 21. The second end of the first branch flow path section P1a is referred to as a first input / output section C3a of the hydraulic pressure adjustment module 3. The second branch flow path section P2a has a first end connected to the shared connection point C1 and a second end connected to the second hydraulic chamber 22. The second end of the second branch flow path section P2a is referred to as a second input / output section C3b of the hydraulic pressure adjustment module 3.

[0026] The mutual flow passage P3 has a first end connected to the first branch flow passage portion P1a and a second end connected to the second branch flow passage portion P2a. The portion where the first end of the mutual flow passage P3 is connected in the first branch flow passage portion P1a is referred to as a first branch connection point C2a. Similarly, the portion where the second end of the mutual flow passage P3 is connected in the second branch flow passage portion P2a is referred to as a second branch connection point C2b. In other words, the mutual flow passage P3 has a function of moving the hydraulic oil 200 from the first branch flow passage portion P1a to the second branch flow passage portion P2a and a function of moving the hydraulic oil 200 from the second branch flow passage portion P2a to the first branch flow passage portion P1a. The first branch flow passage portion P1a is connected to the first hydraulic chamber 21, and the second branch flow passage portion P2a is connected to the second hydraulic chamber 22. Therefore, the mutual flow path P3, in cooperation with the first branch flow path portion P1a and the second branch flow path portion P2a, has a function of moving the hydraulic oil 200 from the first hydraulic chamber 21 to the second hydraulic chamber 22. Furthermore, the mutual flow path P3, in cooperation with the first branch flow path portion P1a and the second branch flow path portion P2a, has a function of moving the hydraulic oil 200 from the second hydraulic chamber 22 to the first hydraulic chamber 21.

[0027] A first opening / closing control valve 31 is provided in the first branch flow passage portion P1a of the first open flow passage P1. More specifically, the first opening / closing control valve 31 is provided between the common connection point C1 and the first branch connection point C2a. The first opening / closing control valve 31 alternates between an open state in which the hydraulic oil 200 is permitted to move from the first hydraulic chamber 21 to the accumulator 38 and a closed state in which the hydraulic oil 200 is prohibited from moving. The first opening / closing control valve 31 may be of an electric type. Also, the first opening / closing control valve 31 may be of a type that operates in response to fluctuations in the hydraulic pressure of the hydraulic oil 200.

[0028] A second opening / closing control valve 32 is provided in the second branch flow passage portion P2a of the second open flow passage P2. More specifically, the second opening / closing control valve 32 is provided between the common connection point C1 and the second branch connection point C2b. The second opening / closing control valve 32 alternates between an open state in which the hydraulic oil 200 is permitted to move from the second hydraulic chamber 22 to the accumulator 38 and a closed state in which the hydraulic oil 200 is prohibited from moving. The second opening / closing control valve 32 may be either an electric type or a passive type.

[0029] The mutual on-off control valve 33 is provided in the mutual flow path P3. The mutual on-off control valve 33 alternates between an open state, which allows the hydraulic oil 200 to move from the first hydraulic chamber 21 to the second hydraulic chamber 22 and from the second hydraulic chamber 22 to the first hydraulic chamber 21, and a closed state, which prohibits the movement of the hydraulic oil 200. The mutual on-off control valve 33 may be of an electric type, like the first on-off control valve 31, or may be of a type that operates in response to fluctuations in the hydraulic pressure of the hydraulic oil 200.

[0030] The accumulator 38 is connected to the first hydraulic chamber 21 via a first open flow path P1. In addition, the accumulator 38 is connected to the second hydraulic chamber 22 via a second open flow path P2.

[0031] Although not shown in FIG. 2, the hydraulic pressure adjustment module 3 may include several additional elements as shown in FIG.

[0032] The hydraulic pressure adjustment module 3 has a first additional flow path P4 and a second additional flow path P5. The first additional flow path P4 is connected to the first branch flow path portion P1a and the shared flow path portion Pc. Specifically, a first end of the first additional flow path P4 is connected between the first opening / closing control valve 31 and the first input / output portion C3a in the first branch flow path portion P1a. A second end of the first additional flow path P4 is connected between the shared connection point C1 and the accumulator 38 in the shared flow path portion Pc. The second additional flow path P5 is connected to the second branch flow path portion P2a and the shared flow path portion Pc. Specifically, a first end of the second additional flow path P5 is connected between the second opening / closing control valve 32 and the second input / output portion C3b in the second branch flow path portion P2a. A second end of the second additional flow path P5 is connected between the shared connection point C1 and the accumulator 38 in the shared flow path portion Pc.

[0033] Further, the hydraulic pressure adjustment module 3 has a first check valve 34, a first orifice 35, a second check valve 36, and a second orifice 37. The first check valve 34 is provided in the first additional flow path P4. Specifically, the input side of the first check valve 34 is connected to the accumulator 38 via the common flow path portion Pc. The output side of the first check valve 34 is connected to the first hydraulic chamber 21 via the first branch flow path portion P1a. The first check valve 34 allows the hydraulic oil 200 to move from the accumulator 38 to the first hydraulic chamber 21, but prohibits the hydraulic oil 200 from moving from the first hydraulic chamber 21 to the accumulator 38. The first orifice 35 is provided in the first additional flow path P4 so as to be in parallel with the first check valve 34. The second check valve 36 is provided in the second additional flow path P5. Specifically, the input side of the second check valve 36 is connected to the accumulator 38 via the shared flow path portion Pc. The output side of the second check valve 36 is connected to the second hydraulic chamber 22 via the second branch flow path portion P2a. The second check valve 36 allows the hydraulic oil 200 to move from the accumulator 38 to the second hydraulic chamber 22, but prohibits the hydraulic oil 200 from moving from the second hydraulic chamber 22 to the accumulator 38. The second orifice 37 is provided in the second additional flow path P5 so as to be in parallel with the second check valve 36.

[0034] The hydraulic control module 3 can switch between a first hydraulic circuit configuration H1, a second hydraulic circuit configuration H2, and a third hydraulic circuit configuration H3. In the first hydraulic circuit configuration H1 (see FIG. 4(b) and the like), the mutual on-off control valve 33 is closed, the first on-off control valve 31 is closed, and the second on-off control valve 32 is closed. In the second hydraulic circuit configuration H2 (see FIG. 4(h) and the like), the mutual on-off control valve 33 is open, the first on-off control valve 31 is closed, and the second on-off control valve 32 is closed. In the third hydraulic circuit configuration H3 (see FIG. 5(b) and the like), the mutual on-off control valve 33 is closed, and one of the first on-off control valve 31 and the second on-off control valve 32 is open, and the other is closed.

[0035] The operation process of the hydraulic damper 1 will be described with reference to Figures 4, 5, and 6. In the following description, it is assumed that the capacity of the accumulator 38 is sufficiently large, and the initial pressure (prestress) of the accumulator 38 is negligibly small compared to the pressure generated in the first hydraulic chamber 21 or the second hydraulic chamber 22 due to vibration of the building 100.

[0036] <First state> FIG. 4(a) shows the building structural section 110 in a first state ST1 in which no earthquake or the like has occurred and the building 100 is not deformed. For example, the brace connection part 103c in the first state ST1 is at position La1. In the following explanation, deformation occurs in the building structural section 110 when an earthquake acts on the building 100. In the following explanation, the deformation of the building structural section 110 is defined as a relative displacement δ (see FIG. 4(d)). The relative displacement δ is the displacement of the structural body connection part 110c with respect to the structural body connection part 110d.

[0037] When the building 100 is in a first state ST1 where the building 100 is not deformed, the hydraulic damper 1 is in a first hydraulic circuit configuration H1 as shown in Fig. 4(b). When in the first hydraulic circuit configuration H1, the states of each control valve are as follows. In Fig. 4(b), a control valve that is closed is indicated by filling the symbol representing the control valve in black. A control valve that is open is indicated by filling the symbol representing the control valve in white. First opening / closing control valve 31: Closed Second on-off control valve 32: Closed · Mutual opening and closing control valve 33: Closed

[0038] In the first state ST1, the piston 24 may be located approximately in the center of the cylinder 23. In the first state ST1, the pressure in the first hydraulic chamber 21 is approximately the same as the pressure in the second hydraulic chamber 22. In FIG. 4(b), the pressures in the first hydraulic chamber 21 and the second hydraulic chamber 22 are illustrated by the density of the hatching. A relatively high pressure state is indicated by thick hatching. A relatively low pressure state is indicated by thin hatching. Since there is no significant difference between the pressures in the first hydraulic chamber 21 and the second hydraulic chamber 22 in the first state ST1, the density of the hatching in the first hydraulic chamber 21 is the same as the density of the hatching in the second hydraulic chamber 22. In addition, in the first state ST1, the pressure in the first hydraulic chamber 21 is the same as the pressure in the accumulator 38, and the pressure in the second hydraulic chamber 22 is also the same as the pressure in the accumulator 38.

[0039] Here, the mechanical model K120 of the hydraulic damper 1 shown in Fig. 4(c) etc. will be described. Fig. 4(c) shows the mechanical model K120 in which an elastic element E103a simulating the stiffness of the brace 103a, an elastic element E1 simulating the stiffness of the hydraulic damper 1, and a damping element D1 simulating the damping coefficient C of the hydraulic damper 1 are connected in series in this order. In the mechanical model K120 shown in Fig. 4(f) etc. used in the following description, the elastic elements E103a and E1 are illustrated as one composite elastic element E120. The composite elastic element E120 has a stiffness equivalent to the stiffness of the elastic element E103a and the elastic element E1 connected in series.

[0040] The mechanical model K120 of the hydraulic damper 1 can be expressed as a Maxwell model in which a composite elastic element E120 and a damping element D1 are connected in series. This mechanical model K120 takes into consideration the stiffness of the brace 103a. The damping element D1 changes its damping coefficient (C max ) or damping coefficient (C minThat is, the mechanical model K120 shown as the Maxwell model in this embodiment has the nonlinearity of the damping element D1. Here, when the mutual on-off control valve 33, the first on-off control valve 31, and the second on-off control valve 32 are all closed, the damping element D1 is switched to a damping coefficient (C max When the reciprocal opening / closing control valve 33 is open, the damping element D1 has a damping coefficient (C min In the following explanation, the damping coefficient (C max ) is infinity, and the damping coefficient (C min ) is assumed to be zero.

[0041] FIG. 4(c) shows the mechanical model K120 of the building structural part 110 in the first state ST1. In the first state ST1, the relative displacement (δ) is zero. In the first state ST1, the spring length Ld1 of the combined elastic element E120 is the natural length. In other words, since the relative displacement (δ) is zero, no elastic force is generated in the combined elastic element E120. In addition, since the horizontal velocity of the building body connection part 110c is zero, no damping force is generated in the damping element D1.

[0042] Here, attention will be paid to the relationship between the relative displacement (δ) at the skeleton connection part 110c and the internal load generated in the vibration control structure part 120. Fig. 6(a), Fig. 6(b) and Fig. 6(c) show the relationship between the horizontal relative displacement (δ) of the skeleton connection part 11c with respect to the skeleton connection part 110d and the internal load F120 generated in the vibration control structure part 120. For example, the horizontal axis of Fig. 6(a) etc. is the relative displacement (δ). The vertical axis of Fig. 6(a) etc. corresponds to the internal load F120 generated in the composite elastic element E120 of the dynamic model K120 shown in Fig. 4(c) etc. In the first state ST1, the mutual opening / closing control valve 33, the first opening / closing control valve 31 and the second opening / closing control valve 32 are all closed, so that the damping element D1 has a damping coefficient (C max) is infinite. In other words, the damping element D1 can be regarded as a rigid body. According to this assumption, the internal load F120 may be regarded as the product of the relative displacement (δ) and the rigidity (K) of the composite elastic element E120. In terms of the damper module 2 of FIG. 4(b) etc., the internal load F120 is the product of the differential pressure between the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 and the cross-sectional area of ​​the piston. As described above, in the first state ST1, the relative displacement (δ) is zero. This state (first state ST1: δ=0) is indicated by point GP1 shown in FIG. 6(a).

[0043] <Second state> FIG. 4(d) shows the second state ST2, which is immediately before the direction of the relative displacement (δ) is reversed after the building structural part 110 shown in FIG. 4(a) is deformed by an earthquake or the like, causing the relative displacement (δ) in the structural body connector 110c. In the second state ST2, the position of the structural body connector 110c relative to the structural body connector 110d can be shown as the relative displacement (δ). On the other hand, since the mutual opening and closing control valve 33 of the hydraulic damper 1 is closed, no movement of hydraulic oil occurs between the first hydraulic chamber 21 and the second hydraulic chamber 22. In other words, the piston 24 can be considered to be substantially immobile. Therefore, the brace connector 103c also maintains the position L1a. Then, the influence of the relative displacement (δ) extends to the brace 103a and the brace 103b. Specifically, a compressive force acts on the brace 103a, and a tensile force acts on the brace 103b. Then, the pressure in the first hydraulic chamber 21 increases in response to this compressive force. It is assumed that, during the period from the first state ST1 to the second state ST2, the body coupling portion 110c continues to move in one direction and does not move in the opposite direction.

[0044] As shown in FIG. 4(e), the hydraulic damper 1 continues to maintain the first hydraulic circuit configuration H1 until the building structural part 110 is transformed from the first state ST1 to the second state ST2. More specifically, the hydraulic damper 1 continues to maintain the first hydraulic circuit configuration H1 while the moving direction of the building structure connecting part 110c continues to move in one direction. That is, the hydraulic damper 1 maintains the first hydraulic circuit configuration H1 until the moving direction of the building structure connecting part 110c is reversed. At this time, in the first hydraulic circuit configuration H1, all the control valves are closed and a force acts through the brace 103a, so that the pressure of the first hydraulic chamber 21 continues to rise. On the other hand, the pressure of the second hydraulic chamber 22 is maintained. As a result, the pressure of the first hydraulic chamber 21 becomes relatively higher than the pressure of the second hydraulic chamber 22. In Figure 4 (e), the hatching of the first hydraulic chamber 21 is shown darker than the hatching of the second hydraulic chamber 22 to indicate that the pressure of the first hydraulic chamber 21 is higher than the pressure of the second hydraulic chamber 22.

[0045] As described above, the hydraulic damper 1 maintains the first hydraulic circuit configuration H1 while the body connecting portion 110c continues to move in one direction. The first hydraulic circuit configuration H1 may be maintained on the condition that the body connecting portion 110c is moving, or on another condition. For example, the first hydraulic circuit configuration H1 may be maintained on the condition that the pressure in the first hydraulic chamber 21 is increasing. That is, while the moving direction of the body connecting portion 110c continues to move in one direction, the pressure in the first hydraulic chamber 21 continues to increase, so when the pressure in the first hydraulic chamber 21 is increasing, the hydraulic damper 1 may maintain the first hydraulic circuit configuration H1. In other words, the first hydraulic circuit configuration H1 may be maintained until the pressure in the first hydraulic chamber 21 starts to decrease.

[0046] FIG. 4(f) shows the mechanical model K120 of the building structural part 110 in the second state ST2. In the second state ST2, a relative displacement (δ) occurs between the building body connectors 110c and 110d. In the second state ST2, all the control valves are closed, so that the state of the damping element D1 is the damping coefficient (C max ) As mentioned above, the damping coefficient (C max) is assumed to be infinitely large, the damping element D1 can be regarded as a rigid body. As a result, the hydraulic damper 1 can be simulated as a model including only the composite elastic element E120.

[0047] Here, attention is again focused on the relationship between the relative displacement (δ) in the skeleton connection part 110c and the internal load generated in the vibration control structure part 120. In Fig. 6(a), the transition from the first state ST1 to the second state ST2 is indicated by the line segment GL2. And the second state ST2 is indicated by the point GP2. In the second state ST2, the relative displacement (δ) in the skeleton connection part 110c is the difference between the horizontal displacement generated in the skeleton connection part 110c and the horizontal displacement generated in the skeleton connection part 110c. As a result, the internal load F120 generated in the vibration control structure part 120 is indicated as the product of the relative displacement (δ) and the stiffness (K) of the composite elastic element E120.

[0048] <Third state> Fig. 4(g) shows the building structure unit 110 in the third state ST3. More specifically, Fig. 4(g) shows the state immediately before the transition to the next fourth state ST4 during the period in the third state ST3. The position of the building structure connection unit 110c in the third state ST3 is the same as that in the second state ST2 shown in Fig. 4(d). It can be said that the position of the building structure connection unit 110c shown in Fig. 4(g) shows, for example, the folded-back position of the building structure connection unit 110c.

[0049] When the direction of movement of the body connection part 110c is reversed, the hydraulic damper 1 switches from the first hydraulic circuit configuration H1 to the second hydraulic circuit configuration H2 as shown in Fig. 4(h). When the hydraulic damper 1 is in the second hydraulic circuit configuration H2, the states of the control valves are as follows: · Mutual opening and closing control valve 33: Open First opening / closing control valve 31: Closed Second on-off control valve 32: Closed

[0050] That is, the mutual opening / closing control valve 33 is switched from closed to open. The first opening / closing control valve 31 and the second opening / closing control valve 32 are maintained closed. This causes the hydraulic oil 200 to move from the first hydraulic chamber 21 to the second hydraulic chamber 22. As a result, the pressure difference between the first hydraulic chamber 21 and the second hydraulic chamber 22 is eliminated. At this time, the pressure in the second hydraulic chamber 22 increases, and the pressure in the second hydraulic chamber 22 becomes higher than the pressure in the accumulator 38. When changing from the second state ST2 to the third state ST3, the position of the frame connecting part 110c is maintained, and the position of the brace connecting part 103c moves by the same distance as the relative displacement (δ), so that it moves from position L1a to position La2. As a result, the internal load F120 becomes zero. While the hydraulic oil 200 moves from the first hydraulic chamber 21 to the second hydraulic chamber 22, the strain energy stored in the composite elastic element E120 is consumed as heat.

[0051] The switching operation from the first hydraulic circuit configuration H1 to the second hydraulic circuit configuration H2 may be performed based on the pressure in the first hydraulic chamber 21. That is, the first hydraulic circuit configuration H1 may be switched to the second hydraulic circuit configuration H2 when the pressure in the first hydraulic chamber 21 begins to drop.

[0052] FIG. 4(i) shows the mechanical model K120 of the building structural part 110 in the third state ST3. In the third state ST3, the relative displacement (δ) of the building body connection part 110c is the same as in the second state ST2. On the other hand, in the third state ST3, the mutual opening and closing control valve 33 is opened, and the pressure difference between the first hydraulic chamber 21 and the second hydraulic chamber 22 is eliminated. This phenomenon can be expressed by the contraction of the composite elastic element E120 being eliminated and returning to its natural length. FIG. 4(f) illustrates the contracted composite elastic element E120 as having a spring length Ld2. FIG. 4(i) illustrates the composite elastic element E120 that has returned to its natural length as having a spring length Ld1.

[0053] Here, attention is again paid to the relationship between the relative displacement (δ) of the body connection part 110c and the internal load F120 generated in the vibration control structure part 120. In FIG. 6(b), the transition from the second state ST2 to the third state ST3 is indicated by a line segment GL3. And the third state ST3 is indicated by a point GP3. In the third state ST3, the relative displacement (δ) of the body connection part 110c does not change from the relative displacement (δ) of the body connection part 110c in the second state ST2 because the switching is short. Meanwhile, the internal load F120 generated in the vibration control structure part 120 changes from a predetermined value to zero. Therefore, the transition from the second state ST2 to the third state ST3 is indicated as a line segment GL3 parallel to the Y axis in FIG. 6(c). And the point GP3 ​​indicating the third state ST3 is indicated as a point on the X axis.

[0054] <Fourth state> FIG. 5(a) shows the fourth state ST4 of the building structural part 110 when the hydraulic damper 1 is switched from the second hydraulic circuit configuration H2 to the third hydraulic circuit configuration H3. In the fourth state ST4, the hydraulic oil 200 is moved from the first hydraulic chamber 21 to the accumulator 38. As a result, the pressure in the first hydraulic chamber 21 drops, and the pressure in the second hydraulic chamber 22 becomes higher than the pressure in the first hydraulic chamber 21. In this state, an internal load F120 based on the pressure difference acts on the piston 24 from the second hydraulic chamber 22 toward the first hydraulic chamber 21. Specifically, in a state where the third state ST3 starts to change to the fourth state ST4 (the state of GP3 in FIG. 6(c)), the internal load F120 is zero. An internal load F120 due to the pressure difference with the second hydraulic chamber 22, which increases as the hydraulic oil 200 in the first hydraulic chamber 21 moves to the accumulator 38, acts on the piston 24 in the opposite direction to the movement of the building frame connecting part 110c. At this time, the piston 24 moves a distance corresponding to the internal load F120. In other words, the hydraulic damper 1 extends a distance corresponding to the internal load F120. This causes the brace connecting part 103c to move from position La2 to position La3. As a result, the strain energy corresponding to the internal load F120 is stored in the composite elastic element E120. The time required for this operation is short compared to the vibration of the building, and the movement of the piston 24 due to the deformation of the building can be ignored.

[0055] In the fourth state ST4, the hydraulic damper 1 switches from the second hydraulic circuit configuration H2 to the third hydraulic circuit configuration H3 as shown in Fig. 5(b). In the third hydraulic circuit configuration H3, the states of the control valves are as follows. First opening / closing control valve 31: Open Second on-off control valve 32: Closed · Mutual opening and closing control valve 33: Closed

[0056] Specifically, first, the mutual opening / closing control valve 33 is switched from open to closed. This operation prohibits the movement of the hydraulic oil 200 from the first hydraulic chamber 21 to the second hydraulic chamber 22. After that, the first opening / closing control valve 31 is switched from closed to open, and the first hydraulic chamber 21, which was on the high pressure side in the second state ST2, is connected to the accumulator 38. Just before the first opening / closing control valve 31 is switched from closed to open, the pressure of the first hydraulic chamber 21 is higher than the pressure of the accumulator 38. When the first opening / closing control valve 31 is switched from closed to open, this operation moves the hydraulic oil 200 from the first hydraulic chamber 21 to the accumulator 38. FIG. 5(b) illustrates the state when the first opening / closing control valve 31 is open. As a result, the pressure of the first hydraulic chamber 21 becomes equal to the pressure of the accumulator 38. This operation is called releasing the pressure of the first hydraulic chamber 21. Then, when the pressure in the first hydraulic chamber 21 becomes equal to the pressure in the accumulator 38, the first on-off control valve 31 switches from open to closed. This switches the hydraulic circuit configuration from the third hydraulic circuit configuration H3 to the first hydraulic circuit configuration H1.

[0057] On the other hand, the second opening / closing control valve 32 maintains its closed state. According to this operation, the hydraulic oil 200 in the second hydraulic chamber 22 cannot move to either the first hydraulic chamber 21 or the accumulator 38. That is, the pressure in the second hydraulic chamber 22 is maintained. Then, immediately before the first opening / closing control valve 31 switches from closed to open, the pressure in the first hydraulic chamber 21 was equal to the pressure in the second hydraulic chamber 22. Then, when the first opening / closing control valve 31 switches from closed to open, only the pressure in the first hydraulic chamber 21 drops. As a result, a pressure difference occurs between the first hydraulic chamber 21 and the second hydraulic chamber 22. Specifically, the pressure in the second hydraulic chamber 22 is greater than the pressure in the first hydraulic chamber 21. Then, the internal load F120 caused by this pressure difference acts on the piston 24 from the second hydraulic chamber 22 toward the first hydraulic chamber 21.

[0058] 5(c) shows the mechanical model K120 of the building structural part 110 in the fourth state ST4. As described above, by switching from the third state ST3 to the fourth state ST4, a change in state occurs in which the pressure in the second hydraulic chamber 22 becomes greater than the pressure in the first hydraulic chamber 21, and accordingly the piston 24 receives an internal load F120 based on the differential pressure in the right direction on the page. In the mechanical model K120, the internal load F120 based on this differential pressure can be shown as an extension of the composite elastic element E120 in the right direction on the page. As a result, the composite elastic element E120 extends from the spring length Ld1 to the spring length Ld4.

[0059] Here, attention is again paid to the relationship between the relative displacement (δ) of the body connection part 110c and the internal load F120 generated in the vibration control structure part 120. In FIG. 6(c), the transition from the third state ST3 to the fourth state ST4 is indicated by the line segment GL4. And the fourth state ST4 is indicated by the point GP4. Since the operation in the fourth state ST4 is extremely short, the relative displacement (δ) of the body connection part 110c does not change from the relative displacement (δ) of the body connection part 110c in the third state ST3. Meanwhile, the internal load F120 generated in the vibration control structure part 120 changes from zero to a predetermined value. The predetermined value here is the internal load F120 based on the pressure difference. This internal load F120 based on the pressure difference extends the composite elastic element E120, and is therefore indicated by a minus sign in FIG. 6(c).

[0060] <Fifth state> 5(c), immediately before switching from the fourth state ST4 to the fifth state ST5, the composite elastic element E120 has already stretched a predetermined length in the direction of the internal load F120. From this state, the piston 24 is subjected to a relative displacement (δ) of the body connection part 110c, which is oriented leftward in the drawing.

[0061] 5(f) is a mechanical model K120 showing how the piston 24 moves to the left on the page due to the relative displacement (δ) of the body connection part 110c from the state of displacement (Ld4) due to the internal load F120. The increase in the load acting on the composite elastic element E120 is shown by the composite elastic element E120 being further extended to the left on the page due to the relative displacement (δ) of the body connection part 110c from the state of the spring length Ld4, which is longer than the natural length, spring length Ld1, due to the internal load F120.

[0062] 5(e), when the piston 24 moves with the first on-off control valve 31, the second on-off control valve 32, and the mutual on-off control valve 33 all closed, the hydraulic damper 1 again behaves like a spring. In other words, the pressure in the second hydraulic chamber 22 increases further in response to this movement.

[0063] As shown in FIG. 5(f), the movement of the piston 24 is indicated by a change in the relative displacement (δ) of the body connection part 110c. Furthermore, the load acting on the composite elastic element E120 also increases further. This is indicated by the composite elastic element E120 extending further to the left on the page. As a result, the composite elastic element E120 extends from the spring length Ld4 to the spring length Ld5.

[0064] Here, attention is again focused on the relationship between the relative displacement (δ) of the structural body connection part 110c and the internal load F120 generated in the seismic control structure part 120. In FIG. 6(c), the transition from the fourth state ST4 to the fifth state ST5 is indicated by the line segment GL5. As described above, in the fifth state ST5, the structural body connection part 110c moves leftward on the page, so that the line segment GL5 extends so that the value on the X-axis in FIG. 6(c) gradually decreases. Furthermore, in the fifth state ST5, the composite elastic element E120 further extends leftward on the page (see FIG. 5(f)), so that the absolute value of the internal load F120 gradually increases due to this extension.

[0065] It should be noted that the starting point of the fifth state ST5 has a certain pressure. The piston 24 starts moving leftward from this state, and the end point of the fifth state ST5, when the movement ends, has a higher pressure than the pressure in the first state ST1. This is thought to be due to the internal load F120 caused by the pressure difference that occurs when the piston 24 transitions from the third state ST3 to the fourth state ST4.

[0066] [How to control hydraulic dampers] A method for controlling the hydraulic damper 1 of this embodiment will be described with reference to Fig. 7. Here, the method for controlling the hydraulic damper 1 can be realized by two operation modes.

[0067] In the first mode, the opening and closing control of the first opening and closing control valve 31, the second opening and closing control valve 32, and the mutual opening and closing control valve 33 is performed by the function of the hydraulic circuit elements constituting the hydraulic adjustment module 3. In the first mode, there is no need for a sensor for measuring the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22, or a controller for generating a control signal for each control valve using data obtained from the sensor. In the second mode, the hydraulic damper 1 is provided with a sensor and a controller, and the opening and closing control of the first opening and closing control valve 31, the second opening and closing control valve 32, and the mutual opening and closing control valve 33 is performed by a control signal output by the controller. A specific example of the hydraulic damper 1 operating in the first mode will be described later as a first embodiment. Also, a specific example of the hydraulic damper 1 operating in the second mode will be described later as a second embodiment.

[0068] Below, a method of controlling a hydraulic damper will be described using the hydraulic damper 1 operating in the first mode as an example. In the following description, the operation of the hydraulic damper 1 will be indicated as "Step S." The operation of the hydraulic damper 1 described as "Step S" is an active operation that occurs due to a preset function of the hydraulic damper 1. Furthermore, an event that triggers the operation of the hydraulic damper 1 will be indicated as "Event N."

[0069] First, in a first state ST1 in which no earthquake has occurred (see Figs. 4(a), 4(b), and 4(c)), the hydraulic damper 1 is in the first hydraulic circuit configuration H1 (step S1). Step S1 includes closing the first on-off control valve 31 (step S11), closing the second on-off control valve 32 (step S12), and closing the reciprocal on-off control valve 33 (step S13). These steps S11, S12, and S13 may be executed in any order.

[0070] Next, assume that an earthquake occurs (event N1). The occurrence of the earthquake causes a second state ST2 (event N2: see Figs. 4(d), 4(e) and 4(f)) in which the piston 24 starts to move toward the first hydraulic chamber 21. In the second state ST2, the hydraulic damper 1 maintains the first hydraulic circuit configuration H1 (step S2).

[0071] Next, the direction of the external load is reversed (event N3). As a result, the moving direction of the piston 24 is reversed (event N4). The state in which the moving direction of the piston 24 is reversed is the third state ST3 (see FIG. 4(g), FIG. 4(h), and FIG. 4(i)). When the third state ST3 is reached, the hydraulic damper 1 switches from the first hydraulic circuit configuration H1 to the second hydraulic circuit configuration H2 (step S3). Step S3 includes maintaining the first opening / closing control valve 31 closed (step S31), maintaining the second opening / closing control valve 32 closed (step S32), and switching the reciprocal opening / closing control valve 33 from closed to open (step S33). These steps S31, S32, and S33 may be executed in any order.

[0072] Next, the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 become balanced (event N5). When the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 become balanced, the hydraulic damper 1 switches from the second hydraulic circuit configuration H2 to the third hydraulic circuit configuration H3 (step S4). Step S4 includes switching the mutual opening / closing control valve 33 from open to closed (step S41), switching the first opening / closing control valve 31 from closed to open (step S42), and maintaining the second opening / closing control valve 32 closed (step S43). Step S41 is executed prior to step S42. Since step S43 is for maintaining the closed state, the order of steps S41 and S42 is irrelevant.

[0073] The pressure in the first hydraulic chamber 21 is released. The state in which the pressure in the first hydraulic chamber 21 is released is the fourth state ST4 (see Figs. 5(a), 5(b) and 5(c)). The first opening / closing control valve 31 of the hydraulic damper 1 is switched from closed to open (step S42). As a result, the pressure in the first hydraulic chamber 21 decreases, and the piston 24 moves from the second hydraulic chamber 22 in the direction of the first hydraulic chamber 21 due to the internal load F120 based on the pressure difference generated between the first hydraulic chamber 21 and the second hydraulic chamber 22 (step N6).

[0074] When the pressure in the first hydraulic chamber 21 is balanced with the pressure in the accumulator 38 (event N7), the hydraulic damper 1 switches from the third hydraulic circuit configuration H3 to the first hydraulic circuit configuration H1 (step S5). Step S5 includes switching the first opening / closing control valve 31 from open to closed (step S51), maintaining the second opening / closing control valve 32 closed (step S52), and maintaining the reciprocal opening / closing control valve 33 closed (step S53). These steps S51, S52, and S53 may be executed in any order.

[0075] In the fifth state ST5 (event N8: see Figures 5(d), 5(e) and 5(f)) in which the first opening / closing control valve 31, the second opening / closing control valve 32 and the mutual opening / closing control valve 33 are all closed, the hydraulic damper 1 has the first hydraulic circuit configuration H1. Thereafter, steps S2 to S5 are executed again. Note that position Lb1 indicated by a dashed line in Figure 5(d) is the position of the structural body connection part 110c when the building 100 is in the first state ST1 in which it is not deformed.

[0076] [Action and Effects] The embodiments described in detail so far relate to a hydraulic damper for vibration control used to reduce shaking of a building caused by a vibration external force F100 such as an earthquake or wind, a control method for a hydraulic damper opening / closing control valve that controls an opening / closing control valve, and a hydraulic damper used in the method.

[0077] Vibration control technologies to be applied to structures are being studied. For example, one type of vibration control technology is a technology that uses oil dampers attached to a structure to absorb energy given to the structure due to earthquakes, etc. In general, the damping coefficient of an oil damper is constant. As a result, there is a limit to the amount of energy that can be absorbed due to constraints imposed not only by the rigidity of the vibration control device itself, but also by the rigidity of the connecting members that attach the vibration control device to the structure, and the rigidity caused by deformation of the surrounding frame on which the vibration control device is installed.

[0078] Japanese Patent Application Publication No. 2002-013310 discloses a variable damping device for a seismically controlled structure, and Japanese Patent Application Publication No. 2006-153068 discloses a damping coefficient switching hydraulic damper. These devices have an on-off control valve provided in the flow path of the oil damper. The opening of the on-off control valve is controlled to either fully open or fully closed to improve the amount of energy absorption. This control makes it possible to maximize the amount of energy absorption under the constraints caused by the rigidity described above.

[0079] JP 2014-163502 A discloses a control method for a hydraulic damper opening / closing control valve. A device to which this control method is applied has a hydraulic tank in addition to a hydraulic damper and an opening / closing control valve. The hydraulic tank and the opening / closing control valve can regenerate energy given to a structure and divert the regenerated energy to vibration control. As a result, the amount of energy absorbed is further improved.

[0080] The device disclosed in JP 2014-163502 A includes a hydraulic tank and three on-off control valves as components for energy regeneration, which complicates the structure of the components added to the hydraulic damper.

[0081] Therefore, this embodiment describes a hydraulic damper and a method for controlling the hydraulic damper that exceeds the theoretical maximum energy absorption amount according to the Maxwell model by utilizing an accumulator and a hydraulic chamber without adding a hydraulic tank.

[0082] The hydraulic damper 1 includes a cylinder 23 having an internal space 20 filled with hydraulic oil, a piston 24 that is disposed inside the cylinder 23 and divides the internal space 20 into a first hydraulic chamber 21 and a second hydraulic chamber 22, and that reciprocates inside the cylinder 23, and a hydraulic adjustment module 3 connected to each of the first hydraulic chamber 21 and the second hydraulic chamber 22. The hydraulic adjustment module 3 is connected to the first hydraulic chamber 21 via a first open flow path P1 and to the second hydraulic chamber 22 via a second open flow path P2, and includes an accumulator 38 for releasing the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22, and a pressure adjusting module 3 having one end connected to the first hydraulic chamber 21 and the other end connected to the second hydraulic chamber 22. The hydraulic fluid supply system includes a mutual opening / closing control valve 33 provided in a mutual flow path P3 connected to the hydraulic chamber 22, and switching between an open state to allow the movement of hydraulic oil from the first hydraulic chamber 21 to the second hydraulic chamber 22 and from the second hydraulic chamber 22 to the first hydraulic chamber 21 and a closed state to prohibit the movement of hydraulic oil, a first opening / closing control valve 31 provided in the first open flow path P1, and switching between an open state to allow the movement of hydraulic oil from the first hydraulic chamber 21 to the accumulator 38 and a closed state to prohibit the movement of hydraulic oil, and a second opening / closing control valve 32 provided in the second open flow path P2, and switching between an open state to allow the movement of hydraulic oil from the second hydraulic chamber 22 to the accumulator 38 and a closed state to prohibit the movement of hydraulic oil.

[0083] The hydraulic adjustment module 3 of the hydraulic damper 1 has a mutual opening and closing control valve 33, a first opening and closing control valve 31, and a second opening and closing control valve 32. In this configuration, for example, when the hydraulic pressure of the first hydraulic chamber 21 on the high pressure side starts to decrease, the mutual opening and closing control valve 33 can be opened. This allows the hydraulic oil of the first hydraulic chamber 21 on the high pressure side to be moved to the second hydraulic chamber 22 on the low pressure side, and the hydraulic pressure of the pair of hydraulic chambers, the first hydraulic chamber and the second hydraulic chamber, can be balanced. In addition, since the hydraulic adjustment module 3 has the first opening and closing control valve 31, when the pressure difference between the first hydraulic chamber 21 and the second hydraulic chamber 22 is eliminated, the first opening and closing control valve 31 can be switched from closed to open, and the hydraulic oil of the first hydraulic chamber 21, which was on the high pressure side, can be moved to the accumulator 38. This allows a pressure difference to be generated between the first hydraulic chamber 21 and the second hydraulic chamber 22. As a result, an offset can be applied to the load of the hydraulic damper 1 to increase the amount of energy absorption.

[0084] In addition, since the hydraulic damper 1 does not have an auxiliary hydraulic tank, the configuration of the hydraulic circuit can be simplified. As a result, the energy absorption amount can be improved while simplifying the structure of the hydraulic damper. In addition, since the accumulator 38 provided in a general hydraulic damper can be applied as the pressure release section, it is possible to prevent the damper from becoming larger than a general hydraulic damper and also to prevent an increase in cost.

[0085] The hydraulic pressure adjustment module 3 alternately switches between a first hydraulic circuit configuration in which the mutual on-off control valve 33 is closed, the first on-off control valve 31 is closed, and the second on-off control valve 32 is closed, a second hydraulic circuit configuration in which the mutual on-off control valve 33 is open, the first on-off control valve 31 is closed, and the second on-off control valve 32 is closed, and a third hydraulic circuit configuration in which the mutual on-off control valve 33 is closed, and one of the first on-off control valve 31 and the second on-off control valve 32 is open and the other is closed. This configuration makes it possible to appropriately improve the amount of energy absorption.

[0086] The hydraulic pressure regulating module 3 switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration in this order. This configuration makes it possible to appropriately improve the amount of energy absorption.

[0087] The hydraulic pressure adjustment module 3 switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration based on the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22. This makes it possible to switch between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration based on the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22, for example, without being based on the moving direction of the piston.

[0088] The hydraulic circuit adjustment module 3 is configured to have a first hydraulic circuit configuration when the pressure in the first hydraulic chamber 21 increases in response to the movement of the piston 24, and when the direction of movement of the piston 24 is reversed, the hydraulic circuit adjustment module 3 switches from the first hydraulic circuit configuration to a second hydraulic circuit configuration in which the mutual on-off control valve 33 is open and the first on-off control valve 31 and the second on-off control valve 32 are closed, and when the pressure difference between the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 becomes smaller than a threshold value, the hydraulic circuit adjustment module 3 is configured to have a third hydraulic circuit configuration in which the first on-off control valve 31 is open and the second on-off control valve 32 is closed. With this configuration, it is possible to appropriately improve the amount of energy absorption. That is, when the pressure difference between the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 becomes smaller than a threshold value, the hydraulic circuit adjustment module 3 is configured to have the first on-off control valve 31 open and the second on-off control valve 32 closed, thereby generating a pressure difference between the first hydraulic chamber 21 and the second hydraulic chamber 22. This pressure difference acts in the opposite direction to the movement direction of the piston 24. As a result, an offset can be applied to the load, thereby increasing the amount of energy absorption.

[0089] That is, when the building is deformed and the pressure in the first hydraulic chamber 21 is increasing, the vibration energy of the building is stored in the hydraulic damper 1 and the springs of the braces 103a, 103b, and when the vibration of the building 100 is reversed (i.e., when the pressure in the first hydraulic chamber 21 starts to decrease), hydraulic oil is transferred to the second hydraulic chamber 22 in one go, and the pressures of the first hydraulic chamber 21 and the second hydraulic chamber 22 are balanced. After that, the first opening / closing control valve 31 is opened to transfer the hydraulic oil in the first hydraulic chamber 21 to the accumulator 38, and a sudden pressure difference is generated between the first hydraulic chamber 21 and the second hydraulic chamber 22. This provides an offset to the load of the hydraulic damper 1, and increases the amount of energy absorption.

[0090] The method for controlling the hydraulic damper includes a first step of prohibiting the outflow of hydraulic oil from the first hydraulic chamber 21 and the second hydraulic chamber 22 when the pressure in the first hydraulic chamber 21 increases in response to the movement of the piston 24, a second step of allowing the movement of hydraulic oil from the first hydraulic chamber 21 to the second hydraulic chamber 22 when the direction of movement of the piston 24 is reversed, and a third step of prohibiting the movement of hydraulic oil from the first hydraulic chamber 21 to the second hydraulic chamber 22 and releasing the pressure of the first hydraulic chamber 21 when the pressure difference between the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 becomes smaller than a threshold value. This method for controlling a hydraulic damper also makes it possible to improve the energy absorption amount while simplifying the structure of the hydraulic damper, similar to the hydraulic damper 1.

[0091] <First Example> FIG. 8 is a hydraulic circuit diagram of the hydraulic adjustment module 3A provided in the hydraulic damper 1A according to the first embodiment. The hydraulic adjustment module 3A has a first on-off valve 51 and a second on-off valve 52 as main elements. The first on-off valve 51 functions as a mutual on-off control valve 33. The hydraulic adjustment module 3A has a pilot operated valve 54 as an element for switching the operation of the first on-off valve 51. In addition, a buffer 62, orifices 60, 63, and 64, a variable orifice 65, check valves 66 and 67, and a relief valve 68 are provided in a flow path connecting these elements. The second on-off valve 52 functions as the first on-off control valve 31 or the second on-off control valve 32 depending on the position of the directional control valve 55. The position of the directional control valve 55 follows the relationship between the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22. Furthermore, the hydraulic adjustment module 3A has a first switching valve 53. The first switching valve 53 functions as an element for releasing the pressure accumulated in the buffer 62. In addition, the hydraulic pressure regulating module 3A has a relief valve 39 for releasing the excessive pressure in the first hydraulic chamber 21 and a relief valve 40 for releasing the excessive pressure in the second hydraulic chamber 22.

[0092] The hydraulic pressure adjustment module 3A further has a directional control valve 55. The directional control valve 55 connects one of the first hydraulic chamber 21 and the second hydraulic chamber 22 to the first on-off valve 51, and connects the other of the first hydraulic chamber 21 and the second hydraulic chamber 22 to the second on-off valve 52, depending on the relationship between the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22.

[0093] <First hydraulic circuit configuration> In the first hydraulic circuit configuration H1, the first on-off valve 51 is closed and the second on-off valve 52 is also closed. It is assumed that the pressure in the first hydraulic chamber 21 is higher than the pressure in the second hydraulic chamber 22. In this state, the pressure acting on the right surface 55b of the directional control valve 55 is higher than the pressure acting on the left surface 55a, so that the first hydraulic chamber 21 is connected to the front surface 51a of the first on-off valve 51 and the second hydraulic chamber 22 is connected to the front surface 52a of the second on-off valve 52. When the pressure in the first hydraulic chamber 21 is high and the pressure in the first hydraulic chamber 21 is rising, the pressure acting on the left surface 54a of the pilot operated valve 54 is lower than the sum of the pressure acting on the right surface 54b of the pilot operated valve 54 and the pressure of the spring, so that the pilot operated valve 54 is closed. At this time, the first on-off valve 51 is in a closed state. In addition, the first on-off valve 51 prohibits the movement of the hydraulic oil 200 from the first hydraulic chamber 21 to the second hydraulic chamber 22, and therefore functions as a mutual on-off control valve 33. In addition, the second on-off valve 52 prohibits the movement of the hydraulic oil 200 from the first hydraulic chamber 21 to the accumulator 38, and therefore functions as a first on-off control valve 31.

[0094] The pressure of the first hydraulic chamber 21 accumulated in the buffer 62 acts on the back surface 52b of the second on-off valve 52. The pressure of the first hydraulic chamber 21 acting on the back surface 52b of the second on-off valve 52 is higher than the pressure of the second hydraulic chamber 22 acting on the front surface 52a of the second on-off valve 52, so the second on-off valve 52 closes. At this time, the second on-off valve 52 prohibits the movement of the hydraulic oil 200 from the second hydraulic chamber 22, so it functions as the second on-off control valve 32.

[0095] <Second hydraulic circuit configuration> The second hydraulic circuit configuration H2 is realized by a state in which the first on-off valve 51 is open and the second on-off valve 52 is also closed. It is assumed that the pressure in the first hydraulic chamber 21 is higher than the pressure in the second hydraulic chamber 22, but the pressure in the first hydraulic chamber 21 has begun to drop. A check valve 66 is provided in the flow path between the buffer 62 and the first hydraulic chamber 21. This check valve 66 allows the buffer 62 to maintain a high pressure state. In this state, the pressure from the buffer 62 acting on the left surface 54a of the pilot operated valve 54 (the maximum pressure of the first hydraulic chamber 21) becomes higher than the pressure of the first hydraulic chamber 21 acting on the right surface 54b of the pilot operated valve 54. As a result, the pilot operated valve 54 opens. When the pilot operated valve 54 opens, the pressure acting on the back surface 51b of the first on-off valve 51 becomes lower than the pressure acting on the front surface 51a of the first on-off valve 51, so the first on-off valve 51 opens. As a result, a flow path is formed that runs from the first hydraulic chamber 21 through the directional control valve 55 and the first on-off valve 51. This flow path corresponds to the mutual flow path P3 shown in Fig. 2. At this time, the first on-off valve 51 allows the movement of the hydraulic oil 200 from the first hydraulic chamber 21 to the second hydraulic chamber 22, and therefore functions as the mutual on-off control valve 33.

[0096] In addition, the pressure from the buffer 62 acting on the back surface 52b of the second on-off valve 52 (maximum pressure value of the first hydraulic chamber 21) is higher than the decreasing pressure of the first hydraulic chamber 21 acting on the front surface 52a of the second on-off valve 52. Therefore, the second on-off valve 52 is closed. At this time, the second on-off valve 52 prohibits the movement of the hydraulic oil 200 from the second hydraulic chamber 22, and therefore functions as the second on-off control valve 32. In other words, depending on the state of the directional control valve 55, it is determined whether the second on-off valve 52 functions as the first on-off control valve 31 or the second on-off control valve 32. Therefore, in the first embodiment, the first on-off control valve 31 and the second on-off control valve 32 shown in FIG. 2 and the like are realized by one second on-off valve 52.

[0097] <Third hydraulic circuit configuration> The third hydraulic circuit configuration H3 is realized by a state in which the first on-off valve 51 is closed and the second on-off valve 52 is open. It is assumed that the pressure in the first hydraulic chamber 21 is balanced with the pressure in the second hydraulic chamber 22, and the pressure in the second hydraulic chamber 22 is slightly greater than the pressure in the first hydraulic chamber 21. In this state, the pressure acting on the left surface 55a of the directional control valve 55 is greater than the pressure acting on the right surface 55b, so that the first hydraulic chamber 21 is connected to the front surface 52a of the second on-off valve 52 and the second hydraulic chamber 22 is connected to the front surface 51a of the first on-off valve 51. During this time, when the pressure in the first hydraulic chamber 21 is balanced with the pressure in the second hydraulic chamber 22, the pressures acting on the left surface 53a and the right surface 53b of the first switching valve 53 are also balanced. As a result, the first switching valve 53 connects the buffer 62 to the accumulator 38. Then, the pressure acting on the left surface 54a of the pilot operated valve 54 is balanced with the pressure acting on the right surface 54b of the pilot operated valve 54, and the pilot operated valve 54 is closed by the spring of the right surface 54b. As a result, the first opening and closing valve 51 is closed. At this time, the first opening and closing valve 51 prohibits the movement of the hydraulic oil 200 from the second hydraulic chamber 22 to the first hydraulic chamber 21, so it functions as a mutual opening and closing control valve 33. Also, when the pressure accumulated in the buffer 62 is released, the pressure acting on the back surface 52b of the second opening and closing valve 52 becomes lower than the pressure of the first hydraulic chamber 21 that has reached the balanced state acting on the front surface 52a of the second opening and closing valve 52. Therefore, the second opening and closing valve 52 opens, and a flow path from the first hydraulic chamber 21 to the accumulator 38 is formed. This flow path corresponds to the first open flow path P1 shown in FIG. 2. At this time, the second on-off valve 52 allows the hydraulic oil 200 to move from the first hydraulic chamber 21 to the accumulator 38 , and therefore functions as the first on-off control valve 31 .

[0098] The hydraulic damper 1A according to the first example can perform the same operation as the hydraulic damper 1 according to the embodiment. Therefore, like the hydraulic damper 1 according to the embodiment, the hydraulic damper 1A according to the first example can improve the amount of energy absorption while simplifying the configuration of the hydraulic damper 1.

[0099] <Second Example> 9 is a hydraulic circuit diagram of a hydraulic damper 1B according to the second embodiment. In the hydraulic damper 1B, the opening and closing control of the first on-off valve 51 and the second on-off valve 52 is executed by a controller 71. The hydraulic damper 1B according to the second embodiment is a semi-active type.

[0100] The hydraulic pressure adjustment module 3B of the second embodiment has a first on-off valve 51, a second on-off valve 52, a directional control valve 55, a first solenoid valve 69, and a second solenoid valve 70 as elements constituting a hydraulic circuit. Furthermore, the hydraulic pressure adjustment module 3B of the second embodiment further has an orifice 74 and a variable orifice 75 associated with the second on-off valve 52. The arrangement and functions of the first on-off valve 51, the second on-off valve 52, and the directional control valve 55 are generally the same as those of the first embodiment, so detailed explanations are omitted. The first solenoid valve 69 is connected between the back surface 51b of the first on-off valve 51 and the accumulator 38, and switches the first on-off valve 51 between open and closed. The second solenoid valve 70 is connected between the back surface 52b of the second on-off valve 52 and the accumulator 38, and switches the second on-off valve 52 between open and closed. The hydraulic pressure regulating module 3B of the second embodiment may have a displacement meter 79 for measuring the displacement of the piston rod 25.

[0101] The first solenoid valve 69 and the second solenoid valve 70 are switched between open and closed in response to a first control signal C69 and a second control signal C70 provided from a controller 71. For example, when the first solenoid valve 69 is closed, the first on-off valve 51 is also closed. When the first solenoid valve 69 is open, the first on-off valve 51 is also open.

[0102] The hydraulic pressure adjustment module 3B of the second embodiment has, as elements for controlling the hydraulic circuit, a controller 71, a first pressure sensor 72, and a second pressure sensor 73. The first pressure sensor 72 obtains a first pressure value D21 of the first hydraulic chamber 21, and passes the first pressure value D21 to the controller 71. The second pressure sensor 73 obtains a second pressure value D22 of the second hydraulic chamber 22, and passes the second pressure value D22 to the controller 71.

[0103] The controller 71 generates a first control signal C69 and a second control signal C70 using the first pressure value D21 and the second pressure value D22. Then, the controller 71 provides the first control signal C69 to the first solenoid valve 69 and provides the second control signal C70 to the second solenoid valve 70.

[0104] <First hydraulic circuit configuration> The controller 71 controls the first control signal C69 and the second control signal C70 so as to implement the first hydraulic circuit configuration H1 when the following conditions are satisfied. Condition: The first pressure value D21 and the second pressure value D22 are equal to each other, and are also equal to the pressure of the accumulator 38. Alternatively, the first pressure value D21 and the second pressure value D22 are both equal to or less than a predetermined threshold value. Condition: One of the first pressure value D21 and the second pressure value D22 increases over time.

[0105] <Second hydraulic circuit configuration> The controller 71 outputs a first control signal C69 to the first solenoid valve 69. The controller 71 does not output a second control signal C70 to the second solenoid valve 70. As a result, the first on-off valve 51 opens and the second on-off valve 52 closes, thereby realizing the second hydraulic circuit configuration H2. When the following conditions are satisfied, the controller 71 outputs the first control signal C69 and does not output the second control signal C70 in order to realize the second hydraulic circuit configuration H2. Condition: When the larger of the first pressure value D21 and the second pressure value D22 begins to decrease from its maximum value over time.

[0106] <Third hydraulic circuit configuration> The controller 71 does not output the first control signal C69 to the first solenoid valve 69. The controller 71 outputs the second control signal C70 to the second solenoid valve 70 to open the second solenoid valve 70. As a result, the first on-off valve 51 closes and the second on-off valve 52 opens, thereby realizing the third hydraulic circuit configuration H3. When the following conditions are satisfied, the controller 71 does not output the first control signal C69 but outputs the second control signal C70 to realize the third hydraulic circuit configuration H3. Condition: The first pressure value D21 and the second pressure value D22 are equal to each other and higher than the pressure of the accumulator 38. Or, the first pressure value D21 and the second pressure value D22 are both higher than a predetermined threshold value.

[0107] The hydraulic damper 1B according to the second embodiment can also perform the same operation as the hydraulic damper 1 according to the embodiment, in response to an instruction from the controller 71. The hydraulic damper 1 according to the second embodiment is configured with a solenoid valve, a pressure sensor, a controller, etc., and therefore can improve the amount of energy absorption while simplifying the structure of the hydraulic damper as a whole. Furthermore, compared to the hydraulic damper 1A according to the first modified example, the hydraulic damper can further be simplified because it does not require a control circuit including the pilot operated valve 54 and the buffer 62 for controlling the mutual opening / closing control valve 33.

[0108] <Third Example> 10 shows a hydraulic damper 1C according to a third embodiment. In the hydraulic damper 1C, the opening and closing of the first on-off valve 51 is controlled by a pilot operated valve 54, and the opening and closing of the second on-off valve 52 is controlled by a controller 71. The hydraulic damper 1C according to the third embodiment is a hybrid type.

[0109] The hydraulic pressure adjustment module 3C of the third embodiment has, as elements constituting a hydraulic circuit, a first on-off valve 51, a second on-off valve 52, a directional control valve 55, a pilot-operated valve 54, and a second solenoid valve 70. Furthermore, the hydraulic pressure adjustment module 3C of the third embodiment further has a variable orifice 75 associated with the second solenoid valve 70. The arrangement and functions of these elements are generally the same as those of the first and second embodiments, so detailed explanations will be omitted.

[0110] The second solenoid valve 70 switches from closed to open when it receives a second control signal C70 provided from the controller 71. When the second solenoid valve 70 is closed, the second on-off valve 52 is also closed. When the second solenoid valve 70 is open, the second on-off valve 52 is also open.

[0111] <First hydraulic circuit configuration> In the first hydraulic circuit configuration H1, the first on-off valve 51 is closed and the second on-off valve 52 is also closed. The mechanism for closing the first on-off valve 51 is the same as that described in the first embodiment. The mechanism for closing the second on-off valve 52 is the same as that described in the second embodiment.

[0112] <Second hydraulic circuit configuration> In the second hydraulic circuit configuration H2, the first on-off valve 51 is open and the second on-off valve 52 is closed. The mechanism for opening the first on-off valve 51 is the same as that described in the first embodiment. The mechanism for closing the second on-off valve 52 is the same as that described in the second embodiment.

[0113] <Third hydraulic circuit configuration> In the third hydraulic circuit configuration H3, the first on-off valve 51 is closed and the second on-off valve 52 is open. The mechanism for closing the first on-off valve 51 is the same as that described in the first embodiment. The mechanism for opening the second on-off valve 52 is the same as that described in the second embodiment.

[0114] The hydraulic damper 1C according to the third example can also perform the same operation as the hydraulic damper 1 according to the embodiment. Therefore, like the hydraulic damper 1 according to the embodiment, the energy absorption amount can be improved while simplifying the structure of the hydraulic damper.

[0115] <Fourth Example> 11 shows a hydraulic damper 1D according to a fourth embodiment. The hydraulic damper 1D of the fourth embodiment is obtained by replacing the second on-off valve 52 in the hydraulic adjustment module 3A of the hydraulic damper 1A of the first embodiment with a second switching valve 78. The second switching valve 78 is, for example, a spool valve.

[0116] The hydraulic pressure adjustment module 3D of the fourth embodiment has, as elements constituting a hydraulic circuit, a first on-off valve 51, a directional control valve 55, a pilot operated valve 54, a first switching valve 53, and a second switching valve 78. The arrangements and functions of the first on-off valve 51, the pilot operated valve 54, the directional control valve 55, and the first switching valve 53 are generally the same as those of the first embodiment, and therefore detailed explanations will be omitted.

[0117] The second switching valve 78 corresponds to the first opening / closing control valve 31 or the second opening / closing control valve 32 shown in FIG. 3. The second switching valve 78 is disposed between the directional control valve 55 and the accumulator 38. The second switching valve 78 connects the first hydraulic chamber 21 or the second hydraulic chamber 22 to the accumulator 38 according to the relationship between the pressure of the first hydraulic chamber 21 and the pressure of the second hydraulic chamber 22. Specifically, the second switching valve 78 switches between a configuration in which the first hydraulic chamber 21 or the second hydraulic chamber 22 is connected to the accumulator 38 and a configuration in which the first hydraulic chamber 21 or the second hydraulic chamber 22 is disconnected from the accumulator 38. When the pressure of the first hydraulic chamber 21 is higher than the pressure of the second hydraulic chamber 22, the second switching valve 78 disconnects the second hydraulic chamber 22 from the accumulator 38. Furthermore, when the pressure in the second hydraulic chamber 22 is higher than the pressure in the first hydraulic chamber 21, the second switching valve 78 disconnects the first hydraulic chamber 21 from the accumulator 38. Furthermore, when the pressure in the first hydraulic chamber 21 is equal to the pressure in the second hydraulic chamber 22, the second switching valve 78 connects the first hydraulic chamber 21 or the second hydraulic chamber 22 to the accumulator 38.

[0118] <First hydraulic circuit configuration> In the first hydraulic circuit configuration H1, the first on-off valve 51 is closed and the second switching valve 78 is also closed. In other words, the first hydraulic circuit configuration H1 is in a state in which the flow path between the low-pressure hydraulic chamber of the first hydraulic chamber 21 and the second hydraulic chamber 22 and the accumulator 38 is closed. The mechanism for closing the first on-off valve 51 is the same as that of the first on-off valve 51 described in the first embodiment. For example, in the second state ST2 in which the pressure of the first hydraulic chamber 21 is increasing, the pressure of the first hydraulic chamber 21 is higher than the pressure of the second hydraulic chamber 22, and therefore the second switching valve 78 is closed.

[0119] <Second hydraulic circuit configuration> In the second hydraulic circuit configuration H2, the first on-off valve 51 is open and the second switching valve 78 is closed. The mechanism for opening the first on-off valve 51 is the same as that described in the first embodiment. After the first on-off valve 51 is opened, for example, when the hydraulic oil 200 moves from the first hydraulic chamber 21, which has a relatively high pressure, to the second hydraulic chamber 22, which has a relatively low pressure, the pressure difference between the pressures of the first hydraulic chamber 21 and the second hydraulic chamber 22 decreases over time, but the pressure of the first hydraulic chamber 21 is higher than the pressure of the second hydraulic chamber 22. Therefore, the second switching valve 78 is closed.

[0120] <Third hydraulic circuit configuration> In the third hydraulic circuit configuration H3, the first on-off valve 51 is closed and the second switching valve 78 is open. The mechanism for closing the first on-off valve 51 is the same as that described in the first embodiment. For example, when the pressure difference between the pressure in the first hydraulic chamber 21 and the pressure in the second hydraulic chamber 22 becomes smaller over time and the pressure in the first hydraulic chamber 21 becomes equal to the pressure in the second hydraulic chamber 22, the pressure acting on the left surface 78a of the second switching valve 78 becomes equal to the pressure acting on the right surface 78b of the second switching valve 78. As a result, the second switching valve 78 opens.

[0121] The hydraulic damper 1D according to the fourth example can also perform the same operation as the hydraulic damper 1 according to the embodiment. Therefore, like the hydraulic damper 1 according to the embodiment, the energy absorption amount can be improved while simplifying the structure of the hydraulic damper.

[0122] <Fifth Example> 12 shows a hydraulic damper 1E according to a fifth embodiment. In a hydraulic pressure regulation module 3E of the fifth embodiment, a first on-off valve 51E further has a spool valve 51s in addition to a poppet valve 51p. The hydraulic pressure regulation module 3E of the fifth embodiment also has orifices 79, 80 associated with the first on-off valve 51E. Furthermore, the hydraulic pressure regulation module 3E of the fifth embodiment also has a check valve 81 associated with the second on-off valve 52.

[0123] The spool valve 51s is disposed in a flow path P9 connecting the first hydraulic chamber 21 and the second hydraulic chamber 22. The spool valve 51s allows the movement of hydraulic oil between the first hydraulic chamber 21 and the second hydraulic chamber 22 during minute vibrations such as vibrations caused by wind. That is, during minute vibrations such as vibrations caused by wind, even if the pilot operated valve 54 is opened, the poppet valve 51p may not be opened, and the movement of hydraulic oil between the first hydraulic chamber 21 and the second hydraulic chamber 22 may not be permitted. In this way, when the pilot operated valve 54 is open and the poppet valve 51p is closed, the spool valve 51s allows the movement of hydraulic oil between the first hydraulic chamber 21 and the second hydraulic chamber 22 in the flow path P9. When the poppet valve 51p is opened, the spool valve 51s switches to a closed state that prohibits the movement of hydraulic oil between the first hydraulic chamber 21 and the second hydraulic chamber 22 in the flow path P9.

[0124] The hydraulic damper 1E according to the fifth example can also perform the same operation as the hydraulic damper 1 according to the embodiment. Therefore, like the hydraulic damper 1 according to the embodiment, the energy absorption amount can be improved while simplifying the structure of the hydraulic damper.

[0125] The first opening / closing valve 51 has a poppet valve 51p and a spool valve 51s. With this, when minute vibrations that do not operate the poppet valve 51p are applied, the spool valve 51s can be switched between an open state that allows the hydraulic oil to move between the first hydraulic chamber 21 and the second hydraulic chamber 22 and a closed state that prohibits the hydraulic oil from moving. This makes it possible to improve the amount of energy absorption of the hydraulic damper when minute vibrations are applied.

[0126] <Modification> The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present invention. For example, the accumulator 38 may be a hydraulic tank instead of an accumulator. Also, instead of moving the hydraulic oil from the first hydraulic chamber 21 on the high pressure side to the second hydraulic chamber 22 on the low pressure side, the hydraulic oil may be moved from the first hydraulic chamber 21 to the hydraulic tank.

[0127] <Additional Notes> The present disclosure also includes the following configurations.

[0128] The present disclosure relates to a hydraulic damper including: [1] a cylinder, a piston that reciprocates within the cylinder, hydraulic chambers provided on both sides of the piston, and a first opening / closing control valve that is connected to a flow path connecting the two hydraulic chambers and can be switched between open and closed; The hydraulic damper includes an accumulator connected to the hydraulic cylinder and capable of storing pressure oil; a second opening / closing control valve connected to a flow path connecting both hydraulic chambers of the hydraulic damper and an accumulator and capable of being switched between an open state and a closed state; A hydraulic damper in which, while the pressure in one hydraulic chamber is rising, all control valves remain closed and pressure is stored in a buffer, and when the pressure in the hydraulic chamber begins to drop, the first opening / closing control valve is opened, thereby eliminating the pressure difference between the left and right hydraulic chambers, and the first opening / closing control valve is closed again, This is a damping coefficient switching hydraulic damper that incorporates a mechanism that opens the second on-off control valve provided in the flow path connecting the left and right cylinder chambers and the accumulator to rapidly reduce the pressure in one of the cylinder chambers, thereby creating a pressure difference again, and then closes the second on-off control valve.

[0129] The present disclosure is [2] "A damping coefficient switching hydraulic damper as described in [1] above, further comprising a controller that receives a signal from a pressure gauge provided in the hydraulic damper and controls an electromagnetic valve that pilot-operates an opening / closing control valve, thereby enabling opening and closing control of the second opening / closing control valve at the timing described in [1] above."

[0130] The present disclosure is [3] "A damping coefficient switching hydraulic damper, characterized in that in the hydraulic damper described in [1] above, a spool valve that moves due to the pressure difference between the left and right cylinder chambers or a pressure regulating valve that is opened by pilot operation of this spool valve is used as the second opening / closing control valve to enable opening and closing control." [Explanation of symbols]

[0131] 1, 1A, 1B, 1C, 1D, 1E...hydraulic damper, 20...internal space, 21...first hydraulic chamber, 22...second hydraulic chamber, 23...cylinder, 24...piston, 25a, 25b...piston rod, 3, 3A, 3B, 3C, 3D, 3E...hydraulic adjustment module (hydraulic adjustment section, hydraulic adjustment device), 31...first on-off control valve, 32...second on-off control valve, 33...mutual on-off control valve, 38...accumulator (pressure release section), 200...hydraulic oil, H1...first hydraulic circuit configuration, H2...second hydraulic circuit configuration, H3...third hydraulic circuit configuration, P1...first open flow path, P2...second open flow path, P3...mutual flow path.

Claims

1. A cylinder having an internal space filled with hydraulic oil; a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder; a hydraulic pressure adjusting unit connected to each of the first hydraulic chamber and the second hydraulic chamber, The hydraulic pressure adjustment unit is a pressure release section connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber; a mutual opening / closing control valve, one end of which is connected to the first hydraulic chamber and the other end of which is provided in a mutual flow path connected to the second hydraulic chamber, and which alternates between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil; a first opening / closing control valve provided in the first release flow passage and switching between an open state to allow the hydraulic oil to move from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the hydraulic oil from moving; a second opening / closing control valve that is provided in the second release flow path and switches between an open state that allows the hydraulic oil to move from the second hydraulic chamber to the pressure release portion and a closed state that prohibits the hydraulic oil from moving, The hydraulic pressure adjustment unit is a first hydraulic circuit configuration in which the mutual on-off control valve is closed, the first on-off control valve is closed, and the second on-off control valve is closed; a second hydraulic circuit configuration in which the mutual on-off control valve is open, the first on-off control valve is closed, and the second on-off control valve is closed; a third hydraulic circuit configuration in which the mutual on-off control valve is closed, one of the first on-off control valve and the second on-off control valve is open, and the other is closed; The hydraulic damper, wherein the hydraulic pressure adjustment unit switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration in this order.

2. A cylinder having an internal space filled with hydraulic oil; a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder; a hydraulic pressure adjusting unit connected to each of the first hydraulic chamber and the second hydraulic chamber, The hydraulic pressure adjustment unit is a pressure release section connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber; a mutual opening / closing control valve, one end of which is connected to the first hydraulic chamber and the other end of which is provided in a mutual flow path connected to the second hydraulic chamber, and which alternates between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil; a first opening / closing control valve provided in the first release flow passage and switching between an open state to allow the hydraulic oil to move from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the hydraulic oil from moving; a second opening / closing control valve that is provided in the second release flow path and switches between an open state that allows the hydraulic oil to move from the second hydraulic chamber to the pressure release portion and a closed state that prohibits the hydraulic oil from moving, The hydraulic pressure adjustment unit is a first hydraulic circuit configuration in which the mutual on-off control valve is closed, the first on-off control valve is closed, and the second on-off control valve is closed; a second hydraulic circuit configuration in which the mutual on-off control valve is open, the first on-off control valve is closed, and the second on-off control valve is closed; a third hydraulic circuit configuration in which the mutual on-off control valve is closed, one of the first on-off control valve and the second on-off control valve is open, and the other is closed, based on a pressure in the first hydraulic chamber and a pressure in the second hydraulic chamber; The hydraulic pressure adjustment unit is When the pressure in the first hydraulic chamber increases in response to the movement of the piston, the first hydraulic circuit configuration is configured as follows: when the direction of movement of the piston is reversed, switching from the first hydraulic circuit configuration to the second hydraulic circuit configuration in which the mutual on-off control valve is open and the first on-off control valve and the second on-off control valve are closed, a third hydraulic circuit configuration in which, when a pressure difference between the pressure in the first hydraulic chamber and the pressure in the second hydraulic chamber becomes smaller than a threshold value, the first opening / closing control valve is opened and the second opening / closing control valve is closed.

3. A hydraulic adjustment device for a hydraulic damper, comprising: a cylinder having an internal space filled with hydraulic oil; and a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, the piston reciprocating inside the cylinder, a pressure release section connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber; a mutual opening / closing control valve, one end of which is connected to the first hydraulic chamber and the other end of which is provided in a mutual flow path connected to the second hydraulic chamber, and which alternates between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil; a first opening / closing control valve provided in the first release flow passage and switching between an open state to allow the hydraulic oil to move from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the hydraulic oil from moving; a second opening / closing control valve that is provided in the second release flow path and switches between an open state that allows the hydraulic oil to move from the second hydraulic chamber to the pressure release portion and a closed state that prohibits the hydraulic oil from moving, a first hydraulic circuit configuration in which the mutual on-off control valve is closed, the first on-off control valve is closed, and the second on-off control valve is closed; a second hydraulic circuit configuration in which the mutual on-off control valve is open, the first on-off control valve is closed, and the second on-off control valve is closed; a third hydraulic circuit configuration in which the mutual on-off control valve is closed, one of the first on-off control valve and the second on-off control valve is open, and the other is closed; A hydraulic pressure adjusting device that switches between the first hydraulic circuit configuration, the second hydraulic circuit configuration, and the third hydraulic circuit configuration in this order.

4. A hydraulic adjustment device for a hydraulic damper comprising: a cylinder having an internal space filled with hydraulic oil; and a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, the piston reciprocating inside the cylinder, a pressure release section connected to the first hydraulic chamber via a first release flow path and connected to the second hydraulic chamber via a second release flow path, for releasing the pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber; a mutual opening / closing control valve, one end of which is connected to the first hydraulic chamber and the other end of which is provided in a mutual flow path connected to the second hydraulic chamber, and which alternates between an open state to permit the movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and from the second hydraulic chamber to the first hydraulic chamber and a closed state to prohibit the movement of the hydraulic oil; a first opening / closing control valve provided in the first release flow passage and switching between an open state to allow the hydraulic oil to move from the first hydraulic chamber to the pressure release portion and a closed state to prohibit the hydraulic oil from moving; a second opening / closing control valve that is provided in the second release flow path and switches between an open state that allows the hydraulic oil to move from the second hydraulic chamber to the pressure release portion and a closed state that prohibits the hydraulic oil from moving, a first hydraulic circuit configuration in which the mutual on-off control valve is closed, the first on-off control valve is closed, and the second on-off control valve is closed; a second hydraulic circuit configuration in which the mutual on-off control valve is open, the first on-off control valve is closed, and the second on-off control valve is closed; a third hydraulic circuit configuration in which the mutual on-off control valve is closed, one of the first on-off control valve and the second on-off control valve is open, and the other is closed, based on a pressure in the first hydraulic chamber and a pressure in the second hydraulic chamber; When the pressure in the first hydraulic chamber increases in response to the movement of the piston, the first hydraulic circuit configuration is configured as follows: when the direction of movement of the piston is reversed, switching from the first hydraulic circuit configuration to the second hydraulic circuit configuration in which the mutual on-off control valve is open and the first on-off control valve and the second on-off control valve are closed, a third hydraulic circuit configuration in which the first opening / closing control valve is opened and the second opening / closing control valve is closed when a pressure difference between the first hydraulic chamber and the second hydraulic chamber becomes smaller than a threshold value.

5. A method for controlling a hydraulic damper including a cylinder having an internal space filled with hydraulic oil, and a piston disposed inside the cylinder, dividing the internal space into a first hydraulic chamber and a second hydraulic chamber, and reciprocating inside the cylinder, comprising: a first step of prohibiting the hydraulic oil from flowing out of the first hydraulic chamber and the second hydraulic chamber when a pressure in the first hydraulic chamber is increasing in response to movement of the piston; a second step of allowing the hydraulic oil to move from the first hydraulic chamber to the second hydraulic chamber when a direction of movement of the piston is reversed; and a third step of prohibiting movement of the hydraulic oil from the first hydraulic chamber to the second hydraulic chamber and releasing the pressure of the first hydraulic chamber when a pressure difference between the first hydraulic chamber and the second hydraulic chamber becomes smaller than a threshold value.

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