JP3644883B2 - Oil damper for vibration control - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a vibration damping oil damper mainly used for structures (structures) such as buildings and bridges.
[0002]
[Prior art]
  Damping oil dampers are widely used for reasons such as stable damping characteristics, strong damping force, and low performance degradation due to aging.
  Conventionally, a vibration damping oil damper having such advantages is obtained by encapsulating oil in a first oil chamber and a second oil chamber in a cylinder tube partitioned by a piston, and oil from the first oil chamber to the second oil chamber. A relief valve, orifice, etc. are provided in the middle of the flow path for releasing oil, and a check valve is provided. Similarly, relief valves, orifices, etc. are provided in the middle of the flow path for releasing oil from the second oil chamber to the first oil chamber. A structure is provided in which a throttle is provided and a check valve is provided to obtain a reaction force by a throttle resistance generated when oil escapes from one oil chamber to the other when an external force is input.
[0003]
  In the damping oil damper, damping characteristics are set in the low speed range and the high speed range, and the fixed orifice and the pressure regulating valve act in the low speed range, and the relief valve acts in the high speed range.
[0004]
[Problems to be solved by the invention]
  By the way, since the damping oil damper is required to have a compact outer size, it is designed at a high pressure (20 MPa to 40 MPa), so that the piston diameter is also small.
  In order to satisfy the relief performance in the high speed range, the flow rate of the relief valve that can be incorporated in the piston is insufficient. This is because the flow rate is limited by the sheet diameter of the poppet. In order to solve this and satisfy the required design damping force, it is necessary to incorporate a large number of relief valves. However, on the other hand, when a large number of relief valves and check valves are incorporated in the piston, there is a problem of space and costs increase.
[0005]
  Accordingly, an object of the present invention is to provide a vibration damping oil damper that can increase the rated flow rate per relief valve and reduce the required number of relief valves.
[0006]
[Means for Solving the Problems]
  The present invention has been proposed in order to achieve the above-mentioned object. According to the first aspect of the present invention, a rod having a piston in the middle is provided in a cylinder tube so as to be able to advance and retract, and one end of the rod is provided. The oil is sealed in the first oil chamber and the second oil chamber which are protruded from the cylinder tube and defined by the piston, and the oil communicates between the first oil chamber and the second oil chamber. In the oil damper for vibration suppression that obtains the vibration suppression force by the resistance when moving
  A first flow path is formed in the piston to flow oil that moves from the first oil chamber to the second oil chamber when the first oil chamber is pressurized and pressurized, and the second oil chamber is pressurized. Forming a second flow path through which oil moving from the second oil chamber to the first oil chamber when the pressure is increased, and placing the first relief valve in the middle of the first flow path and in the middle of the second flow path The second relief valves are respectively provided in opposite directions so as to have the above resistance,
  The first and second relief valves are
  An opening is formed on the front end surface, a seal portion is formed on the outer periphery, a first port is opened on the outer peripheral surface on the rear end side with respect to the seal portion, and a second port is provided on the rear end side with respect to the first port. The established tubular valve body,
  The valve body is movably fitted in the valve body, and has a large diameter portion that slides against the inner peripheral surface of the hollow portion of the valve body in the longitudinal direction. InIs insideForming a diameter portion, having a seat surface that can be in close contact with the opening edge of the opening portion of the valve body at the front end surface of the middle diameter portion, and forming a narrow tube path from the seat surface toward the rear end side; A thick pressure chamber behind the narrow pipetubeWith the poppet that formed the road,
  Poppet urging means that presses the poppet and presses the seat surface at the tip against the opening edge of the opening of the valve body;
  One of the poppets is connected to the pressure chamber side, the other is connected to the second port, and a throttle channel having a throttle part in the middle;
  Consisting of
The poppet biasing means is
A coil spring fitted into the hollow part of the valve body and the tip pressing the large diameter part of the poppet;
Screwed into the hollow part of the valve body, the head presses the rear end of the coil spring, and the tip of the shaft extending from the head is inserted into the thick pipe passage of the poppet and squeezed into the shaft. A pressure adjusting screw that forms a narrow tube path that becomes a part of the flow path and forms an orifice between the narrow tube path and the outer peripheral surface of the shaft;
Consists ofThis is an oil damper for vibration control.
[0007]
  In the vibration damping oil damper having such a configuration, the first relief valve is provided with a poppet by applying the pressure of the first oil chamber in the first flow path to the tip of the poppet from the opening of the valve body. In the pressurized state where the poppet cannot be pressed against the urging force of the urging means, the oil from the first oil chamber side is released to the second oil chamber side through the second port from the throttle channel, and the resistance at this time is low speed region Acts as a damping force.
[0008]
  Then, in the pressurized state in which the poppet can be pressed against the urging force of the poppet urging means, the first oil chamber is passed through the first port from the gap formed between the tip of the popped back and the opening edge of the valve body. The oil from the side escapes to the second oil chamber side, and the resistance at this time acts as a damping force in the high speed region.
[0009]
  On the other hand, the second relief valve presses the poppet against the urging force of the poppet urging means by causing the pressure of the second oil chamber in the second flow path to act on the tip of the poppet from the opening of the valve body. When the pressure cannot be increased, oil from the second oil chamber side is allowed to escape to the first oil chamber side through the second port from the throttle channel, thereby obtaining a damping force in the low speed region. Further, in the pressurized state in which the poppet can be pressed against the urging force of the poppet urging means, the second oil chamber is passed through the first port from the gap generated between the tip of the popped back and the opening edge of the valve body. The oil from the side escapes to the first oil chamber side, whereby a damping force in the high speed region can be obtained.
[0010]
When the pressure adjusting screw is adjusted, the switching pressure between the low speed range and the high speed range can be set to a desired pressure, and the damping characteristic in the low speed range can be arbitrarily set by the orifice. Therefore, it is possible to easily manufacture a vibration damping oil damper that reliably satisfies the required damper characteristics.
[0011]
  Claim 2The vibration damper according to claim 1 or 2, wherein an accumulator is provided in the rod, and preload is applied to the oil by the accumulator.
[0012]
  Claim 3Is characterized in that a check valve is provided in the middle of a flow path communicating between the accumulator and the oil chamber, and an orifice is provided in the check valve.Claim 2The oil damper for vibration suppression as described in 1.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to the drawings.
  FIG. 1 is a cross-sectional view of a vibration damping oil damper, FIGS. 2 and 3 are enlarged cross-sectional views of essential parts of the oil damper shown in FIG. 1, and FIG. 3 is a cross-sectional view of a relief valve.
[0014]
  A vibration damping oil damper (hereinafter referred to as oil damper 1) includes a cylinder tube 2, a rod 4 that has a piston 3 in the middle thereof, and moves forward and backward in the cylinder tube 2, and a relief valve 5 provided in the piston 3. A check valve 6 and an accumulator 7 provided in the rod 4 are schematically configured, and a spherical bearing 9 a attached to the end of the cylinder tube 2 and a spherical surface attached to the end of the rod 4 protruding from the cylinder tube 2. It is used by being connected to a structure such as a building or a bridge via a bearing 9b.
[0015]
  The cylinder tube 2 is fitted with a first lid member 10 having a hole through which an end of the rod 4 penetrates in one opening portion of the cylindrical material, and has a hole through which the rod 4 penetrates in the other opening portion. The second lid member 11 is fitted and fixed. The first lid member 10 has a cylindrical portion extending outward, and a spherical bearing 9a is provided at the tip of the cylindrical portion. In addition, a sealing material is provided between the cylinder tube 2 and the first and second lid members 10 and 11 and a hole through which the rod 4 passes, and is sealed.
[0016]
  The rod 4 is a hollow shaft provided with a spherical bearing 9b at one end, and a cover cylinder 12 that overlaps the cylinder tube 2 is provided from the spherical bearing 9b side to the other end side. A piston 3 that is thicker than the diameter and divides the inside of the cylinder tube 2 into a first oil chamber 13 and a second oil chamber 14 is formed.
[0017]
  The piston 3 is formed with a large diameter portion 3a in which the outer diameter of the substantially central portion of the outer peripheral surface width (length in the axial direction) is slightly smaller than the vicinity of the inner diameter of the cylinder tube 2, and a groove formed in this portion. Seal ring inside8The middle diameter portion 3b is large enough to allow a flow path to be formed between the large diameter portion 3a and the inner surface of the cylinder tube 2, and one of the middle diameter portions 3b and 3b (the first embodiment in the present embodiment). The first through hole 15 is formed in the diameter direction intersecting with the axial center line on the oil chamber 13 side, and the first inflow communication hole 16 intersecting at the longitudinal center (on the axial center line) of the first through hole 15 is formed. The first outflow communication hole 17 was drilled in parallel with the axial center line from the side surface of the piston 3 on the second oil chamber 14 side toward the opening side of the first through hole 15 and communicated. The first inflow communication hole 16, the first through hole 15, and the first outflow communication hole 17 serve as a first flow path in which oil in the first oil chamber 13 moves to the second oil chamber 14.
[0018]
  Further, the second flow path is formed at a position where the phase is different from that of the first inflow communication hole 16, the first through hole 15, and the first outflow communication hole 17 (the phase is changed by 45 degrees as shown in FIG. 5). To do. That is, the second through hole 20 is formed in the diameter direction in the other middle diameter portion of the piston 3 (on the second oil chamber 14 side), and intersects at the longitudinal center of the second through hole 20 (on the axial center line). The second inflow communication hole 21 is formed in the radial direction, and the second outflow communication hole 22 is parallel to the axial center line from the side surface of the piston 3 on the first oil chamber 13 side toward the opening side of the second through hole 20. The second inflow communication hole 21, the second through hole 20, and the second outflow communication hole 22 that are drilled in and communicated with each other are used as a second flow path.
[0019]
  Then, the first relief valve 5a is provided in the middle of the first flow path, and the second relief valve 5b is provided in the middle of the second flow path in the direction of resistance in the opposing flow.
[0020]
  Specifically, the first relief valve 5a is disposed at two locations where the first through hole 15 in the diametrical direction and the two first outflow communication holes 17 in the axial direction intersect with each other, The second relief valves 5b are provided at two locations where the second outflow communication holes 22 intersect, and a total of four relief valves 5 are provided.
[0021]
  The first relief valve 5a and the second relief valve 5b are the same differential pressure actuated relief valve 5, and the structure thereof will be described below.
  As shown in FIGS. 4 (a) and 4 (b), the relief valve 5 includes a cylindrical valve body 26 having an opening 23 on the front end surface, a first port 24 and a second port 25 on the side surface, A poppet 30 fitted in the valve body 26 so as to be movable in the axial direction and having a pressure chamber 29 therein, and the poppet 30 is pressed to open the seat surface 31 at the tip of the opening 23 of the valve body 26. Poppet urging means that presses against the edge, and a throttle channel having one of the poppet 30 connected to the pressure chamber 29 side and the other connected to the second port 25 and having a throttle part in the middle. .
[0022]
  The valve body 26 is a cylindrical body having a thick front end portion and a rear end portion and a little thin in the middle, and a seal portion 32 is formed on the outer peripheral surface of the large diameter portion at the front end. The two first ports 24 are opened on the outer peripheral surface of the small-diameter portion at positions opposed to each other in the diametrical direction, and one second port 25 is opened in the narrow-diameter portion on the rear end side of the first port 24. The external thread portion 33 is formed on the outer peripheral surface of the large-diameter portion at the rear end, and the internal thread portion 35 is formed on the inner peripheral surface near the rear end opening of the hollow portion 34.
[0023]
  The poppet 30 fitted in the valve body 26 forms a large diameter portion 36 that slides with respect to the inner peripheral surface of the hollow portion 34 of the valve body 26, and is located at the tip side of the thick diameter portion 36. A diameter portion 37 is formed, and a seat surface 31 that can be in close contact with the opening edge of the opening 23 of the valve body 26 is formed on the front end surface of the medium diameter portion 37, from the center of the seat surface 31 toward the rear end side. A narrow pipe 39 is formed, and a thick pipe 40 serving as the pressure chamber 29 is formed behind the narrow pipe 39. The diameter of the pressure chamber 29 is set slightly smaller than the diameter of the tip opening 23 of the valve body 26 described above.
[0024]
  The poppet urging means that presses the poppet 30 includes a coil spring 41 that is fitted in the hollow portion 34 of the valve body 26 and whose tip presses the large-diameter portion 36 of the poppet 30, and the hollow portion 34 of the valve body 26. And a pressure adjusting screw 42 that presses against the rear end of the coil spring 41. The pressure adjusting screw 42 includes a head portion 43 having a male screw formed on the outer peripheral surface and a shaft portion 44 extending from the head portion 43, and a tip portion of the shaft portion 44 is inserted into the pressure chamber 29 of the poppet 30. In this shaft portion 44, a narrow tube path 45 that becomes a part of the throttle channel is formed, and a thin blade orifice 46 is formed as a throttle portion between the narrow tube channel 45 and the outer peripheral surface of the shaft portion 44. . Therefore, by adjusting the tightening amount of the pressure adjusting screw 42, the spring force with which the coil spring 41 presses the poppet 30 can be adjusted, whereby the set pressure at which the poppet 30 opens (switching from the low speed range to the high speed range). Pressure) can be set as appropriate. And since the thin blade orifice 46 is used as the throttle part, it is hardly affected by the temperature and can exhibit a stable low-speed damping characteristic.
[0025]
  In the relief valve 5 having such a configuration, when the front end opening 23 of the valve body 26 is on the oil inflow side, the first port 24 and the second port 25 are on the outflow side, and the oil pressure on the inflow side rises, This pressure P acts on the poppet 30. The pressure receiving area of the poppet 30 receiving this pressure P acts on the ring-shaped inner wall 29 ′ on the opening 23 side in the inner wall of the pressure chamber 29 in the opposite direction to the pressure P acting on the tip surface of the poppet 30. 4B, the area obtained by subtracting the area of the ring-shaped inner wall 29 ′ of the pressure chamber 29 from the area of the tip opening 23 of the valve body 26. The force that actually presses the poppet 30 toward the urging means is (area of the tip opening 23 of the valve body 26−area of the pressure chamber ring-shaped inner wall 29 ′) × P. That is, when the pressure chamber 29 is provided in the poppet 30 of the relief valve 5, the pressure receiving area of the poppet 30 can be made much smaller even if the area of the tip opening 23 of the valve body 26 is set as usual or larger. Thus, even if the set flow rate is increased, the spring force of the urging means can be made much smaller than before.
[0026]
  Therefore, if the size is the same as that of the conventional relief valve, for example, the set pressure can be set higher than the conventional direct acting relief valve 47 shown in FIG. It becomes possible. For this reason, when the oil damper 1 is provided, the number of relief valves 5 can be reduced to 1/2 to 1/3 of the conventional one.
[0027]
  When the poppet 30 is not moved by the pressure P, that is, in a low pressure state in which the poppet 30 does not open (not reach the set pressure), the pressure P is passed through the narrow pipe lines 39 and 45.Thin bladeThe orifice 46 is squeezed and flows out of the valve body 26 from the second port 25 through the gap of the coil spring 41 through the thin blade orifice 46. Since the oil receives a resistance force when passing through the thin blade orifice 46, a damping force in a low speed region can be obtained thereby. Therefore, if the opening area of the thin blade orifice 46 is set as appropriate, the damping force in the low speed region can be adjusted as appropriate. In other words, the thin blade orifice 46 can arbitrarily set the attenuation characteristic in the low speed region. For this reason, it is not necessary to separately install a fixed orifice or a pressure reducing valve, and the number of parts of the oil damper 1 can be reduced to simplify the structure.
[0028]
  On the other hand, when the pressure P exceeding the set pressure set by the poppet urging means is applied, the poppet 30 moves backward against the spring force, so that the seat surface 31 at the tip is separated from the tip opening 23 of the valve body 26. Since a gap is formed between the two, oil from the inflow side can flow from the gap to the outflow side via the first port 24, and the resistance force in this flow becomes the damping force in the high speed region.
[0029]
  A check valve 6 is provided in the piston 3 in addition to the relief valve 5 described above, and the flow of oil to which preload is applied by an accumulator 7 provided in the rod 4 is controlled.
  As shown in FIG. 2, the accumulator 7 applies a preload to the oil in the first and second oil chambers 13 and 14, and the first and second oil chambers 13 and 14 are about to become negative pressure. In this embodiment, a pressure accumulation chamber 50 is formed in the rod 4 on the first oil chamber 13 side, and a spring 51 is provided on one side of the pressure accumulation chamber 50 (on the end portion side of the rod 4). The pre-pressing piston 52 pressed by the cylinder is movably provided, a sleeve-like stopper 53 is provided on the other side (piston 3 side) of the pressure accumulating chamber 50, and the oil in the pressure accumulating chamber 50 is pressurized by the spring force of the spring 51. .
  Note that the accumulator 7 that applies preload to the oil is not limited to the spring type shown in the drawings, and may be a gas-filled type.
[0030]
  And in order to transmit the pressure of this accumulator 7 to the 1st, 2nd oil chambers 13 and 14, a preload channel is formed in rod 4 and piston 3, and check valve 6 is provided in the middle of this preload channel.
[0031]
  In this embodiment, as shown in FIG. 3, a first flow path 54 having one end communicating with the pressure accumulating chamber 50 is drilled from the rod 4 to the middle of the piston 3 so as to be orthogonal to the first flow path 54. The second flow path 55 is formed in the diameter direction in the middle diameter portion 3b of the piston 3 on the accumulator 7 side, and one opening of the second flow path 55 opened in the outer peripheral surface of the middle diameter portion 3b is a blind plug 56. The first check valve 6a is fitted in the vicinity of the other opening, and the third flow path 57 is formed along the axial center line from the side surface of the piston 3 located on the side opposite to the accumulator 7. Then, the second check valve 6 b is fitted in the vicinity of the opening of the third flow path 57.
  The first check valve 6a and the second check valve 6b are the same check valve 6 with a throttle, but are different in orientation when fitted.
[0032]
  As shown in FIG. 6, the check valve 6 has a step portion of the flow passages 55 and 57 as a seat portion, and a poppet 60 in which the front seat surface 59 is in close contact with the seat portion and a hollow portion of the poppet 60. A spring 62 that is fitted in 61 and presses the poppet 60 against the seat portion side, and a plug 63 that presses the spring 62 are included. The poppet 60 has a small hole 64 serving as a throttling portion or an orifice formed at the center of the distal end, and a communication hole 65 communicating with the hollow portion 61 is opened in the diameter direction at the distal end portion. A sufficient gap 66 is secured in the flow path around the tip portion of the poppet 60. Further, the plug 63 is provided with a flow path 67 that communicates between the outside, that is, the oil chamber side and the hollow portion 61 of the poppet 60.
[0033]
  In the check valve 6 having such a configuration, even if the pressure on the plug 63 side (that is, the oil chamber side) suddenly increases, the pressure acts as a force for pressing the poppet 60 against the seat portion. It does not work as a force to open the seat. For this reason, the gap between the two does not open, and in this case, the oil on the plug 63 side is prevented from passing through the check valve 6.
[0034]
  On the other hand, when the pressure on the plug 63 side (that is, the oil chamber side) suddenly decreases, the pressure on the tip end side of the poppet 60 (the pressure accumulator 50 side of the accumulator 7) is relatively increased. 60 moves against the spring force of the spring 62, thereby opening the gap between the poppet 60 and the seat portion, allowing the oil on the tip side of the poppet 60 to pass through the check valve 6, and reducing the pressure in the oil chamber Oil can be replenished.
[0035]
  In the check valve 6, if the pressure on the plug 63 side is higher than the pressure on the tip side of the poppet 60, that is, the pressure on the oil chamber side is higher than the pressure on the pressure accumulation chamber 50 side of the accumulator 7, the oil on the oil chamber side Can pass through the orifice 64 at the tip of the poppet 60 little by little, so that the oil supplied to the oil chamber can be slowly returned to the pressure accumulating chamber 50 side. For this reason, even if compressive force is repeatedly applied to the first and second pressure chambers 13 and 14, it is possible to avoid maintaining a high pressure state, and it is possible to cope with volume changes due to temperature changes.
[0036]
  In the vibration damper 1 having the above-described configuration, in a normal state where no external force is input, the pressure in the first oil chamber 13 and the pressure in the second oil chamber 14 are the same pressure (preload by the accumulator 7). Therefore, the first relief valve 5a and the second relief valve 5b remain closed.
[0037]
  On the other hand, when an external force is applied, for example, due to an earthquake or the like, when a pushing force in the direction in which the rod 4 is pushed to the right in FIG. 1 (the direction in which the rod 4 is contracted) is applied, the piston 3 tries to move to the right, A pressure is generated in the oil chamber 13, and this pressure becomes a reaction force. When the piston 3 moves to the right side, a negative pressure is generated in the second oil chamber 14, but when the pressure drops below the preload, the second check valve 6b opens to compensate for the oil (pressure), so that breathing is possible. High response can be obtained without any phenomenon.
[0038]
  If the reaction force is smaller than a preset pressure, the pressure in the first oil chamber 13 acts on the poppet 30 of the first relief valve 5a up to the set pressure. At this time, since the poppet 30 is stopped and does not open because it is weaker than the set pressure, the oil from the first oil chamber 13 side is squeezed by the thin blade orifice 46 through the thin pipe passages 39 and 45, and this thin blade orifice 46 Then, the gas flows out from the second port 25 to the outside of the valve body 26 through the gap of the coil spring 41, and flows to the second oil chamber 14 side through the first outflow communication hole 17. Since the oil receives a resistance force when passing through the thin blade orifice 46, a damping force in a low speed region can be obtained thereby. In addition, if the opening area of the thin blade orifice 46 is set as appropriate, the damping force in the low speed region can be adjusted as appropriate.
[0039]
  On the other hand, when the reaction force exceeds a preset pressure, a pressure higher than the preset pressure acts on the poppet 30 of the first relief valve 5a. Therefore, the poppet 30 is moved backward, and the seat surface 31 at the front end is separated from the front end opening 23 of the valve body 26 to create a gap therebetween. For this reason, the oil from the first oil chamber 13 side can flow out of the valve body 26 through the first port 24 from the gap, and can flow from the first outflow communication hole 17 to the second oil chamber 14 side. The resistance force in this flow becomes the damping force in the high speed region.
[0040]
  Further, when a pulling force in the direction of pulling the rod 4 (the extending direction of the rod 4) is applied to the right side in FIG. 1, the piston 3 tries to move to the left side, thereby generating pressure in the second oil chamber 14, Pressure becomes reaction force. When the piston 3 moves to the left side, negative pressure tends to be generated in the first oil chamber 13, but when the pressure is lower than the preload, the first check valve 6a is opened to supplement the oil (pressure) and ensure the response. To do.
[0041]
  And when the pressure by tensile force generate | occur | produces, the 2nd relief valve 5b operate | moves similarly to the 1st relief valve 5a in the case of the above-mentioned compression force. That is, if the reaction force is smaller than a preset pressure, the pressure in the second oil chamber 14 acts on the poppet 30 of the second relief valve 5b up to the preset pressure. At this time, since the pressure is lower than the set pressure, the poppet 30 is stopped and does not open. Therefore, the oil from the second oil chamber 14 side is squeezed by the thin blade orifice 46 through the thin pipe passages 39 and 45, and the thin blade orifice 46 is It passes through the gap of the coil spring 41 and flows out from the second port 25 to the outside of the valve body 26 and flows to the first oil chamber 13 side. Since the oil receives a resistance force when passing through the thin blade orifice 46, a damping force in a low speed region can be obtained thereby.
[0042]
  On the other hand, when the reaction force exceeds a preset pressure, a pressure higher than the preset pressure acts on the poppet 30 of the second relief valve 5b. Therefore, the poppet 30 is moved backward, and the seat surface 31 at the front end is separated from the front end opening 23 of the valve body 26 to create a gap therebetween. For this reason, the oil from the second oil chamber 14 side can flow out of the valve body 26 through the first port 24 through the gap and flow to the first oil chamber 13 side. It becomes the damping force of the region.
[0043]
  As described above, even when a compression force and a tensile force are repeatedly applied, the damping oil damper 1 exhibits a force that becomes a reaction force against each force and gradually attenuates and absorbs the vibration. be able to. Therefore, when a building is about to shake due to an earthquake or the like, the above-described compressive force and tensile force are repeatedly applied to the damping oil damper 1, and the oil damper 1 reacts against the compressive force and tensile force. Vibration can be damped by applying force. For this reason, it is effective in preventing a building from being destroyed by an earthquake or the like.
[0044]
【The invention's effect】
  As described above, the present invention has the following effects.
  According to the first aspect of the present invention, since the relief valve incorporated in the piston is provided with a pressure chamber in the poppet, the pressure receiving area of the poppet can be reduced even if the opening of the valve body is large, and the spring can be downsized. Can be planned. Therefore, the relief valve does not become bulky even if the rated flow rate is made larger than before. For this reason, the number of relief valves can be reduced as compared with the prior art, space efficiency can be increased, and manufacturing is facilitated, contributing to cost reduction.
[0045]
  AndThe relief valve poppet urging means is fitted in the hollow portion of the valve body and the tip is pressed into the hollow portion of the valve body, and the head is the rear end of the coil spring. The tip of the shaft that extends from the headtubeSince it is composed of a pressure adjusting screw that is inserted into the channel, forms a narrow tube path that forms part of the throttle channel in the shaft, and forms an orifice between the narrow tube channel and the outer peripheral surface of the shaft. By adjusting the screw, the switching pressure between the low speed range and the high speed range can be set to a desired pressure, and the damping characteristic in the low speed range can be arbitrarily set by an orifice. Therefore, it is possible to easily manufacture and provide a damping oil damper that reliably satisfies the required damper characteristics.
[0046]
  Claim 2According to the invention, an accumulator is provided in the rod, and the oil is preloaded by the accumulator, so that high responsiveness can be expected without a breathing phenomenon.
[0047]
  Claim 3According to the invention, since the check valve is provided in the middle of the flow path communicating between the accumulator and the oil chamber, and the check valve is provided with the orifice, the oil can slowly return to the accumulator, It is possible to cope with volume changes due to temperature changes.
[Brief description of the drawings]
FIG. 1 (a) is a front view of a part of a vibration damping oil damper partially cut away at a check valve channel part, and FIG. 1 (b) is a part of a relief valve channel part. FIG. 3 is a partially cutaway cross-sectional view of a vibration damping oil damper having a cross section.
FIG. 2 is a partially cutaway enlarged cross-sectional view of a damping oil damper having a cross-section partially in the flow path portion of the relief valve.
FIG. 3 is a partially cutaway enlarged front view of a vibration damping oil damper having a cross section partially in the flow path portion of the check valve.
4A is a sectional view of a relief valve according to the present invention, FIG. 4B is an explanatory view showing a pressure receiving area of a poppet of the relief valve shown in FIG. 4A, and FIG. 4C is a conventional direct acting relief valve; (D) is explanatory drawing which shows the pressure receiving area of the poppet of the conventional relief valve shown to (c).
FIG. 5 is a cross-sectional view of an oil damper showing an arrangement of a relief valve and a check valve.
FIG. 6 is a cross-sectional view of a check valve.
FIG. 7 is an explanatory diagram of damping characteristics of an oil damper.
[Explanation of symbols]
  1 Damping oil damper
  2 Cylinder tube
  3 Piston
    3a Large diameter part
    3b Medium diameter part
  4 Rod
  5 Relief valve
  6 Check valve
  7 Accumulator
  8 Seal ring
  9 Spherical bearing
10 First lid
11 Second lid
12 Cover tube
13 First oil chamber
14 Second oil chamber
15 First through hole
16 1st inflow communication hole
17 First outflow communication hole
20 Second through hole
21 Second inflow communication hole
22 Second outflow communication hole
23 opening
24 1st port
25 Second port
26 Valve body
29 Pressure chamber of relief valve
30 Poppet
31 Seat surface
32 Sealing part
33 Male thread
34 Hollow part
35 Female thread
36 Large diameter part
37 Medium diameter part
39 Narrow pipeline
40 thick pipe
41 Coil spring
42 Capillary
43 head
44 Shaft
45 tubule
46 Thin blade orifice
47 Conventional relief valve
50 pressure storage chamber
51 Spring
52 Preload piston
53 Stopper
54 1st flow path
55 Second channel
56 Blind plug
57 3rd flow path
59 Seat surface
60 Poppet
61 Hollow part
62 Spring
63 plug
64 Small hole (orifice)
65 communication hole
66 Clearance
67 flow path

Claims (3)

A rod having a piston in the middle of the cylinder tube is provided in the cylinder tube so as to be able to advance and retreat, and one end of the rod protrudes outside the cylinder tube. In a damping oil damper for damping vibration that obtains damping force by resistance when this oil moves in a flow path communicating between the first oil chamber and the second oil chamber,
A first flow path is formed in the piston to flow oil that moves from the first oil chamber to the second oil chamber when the first oil chamber is pressurized and pressurized, and the second oil chamber is pressurized. Forming a second flow path through which oil moving from the second oil chamber to the first oil chamber when the pressure is increased, and placing the first relief valve in the middle of the first flow path and in the middle of the second flow path The second relief valves are respectively provided in opposite directions so as to have the above resistance,
The first and second relief valves are
An opening is formed on the front end surface, a seal portion is formed on the outer periphery, a first port is opened on the outer peripheral surface on the rear end side with respect to the seal portion, and a second port is provided on the rear end side with respect to the first port. The established tubular valve body,
The valve body is movably fitted in the valve body, and in the middle of the longitudinal direction, a large-diameter portion that slides against the inner peripheral surface of the hollow portion of the valve body is formed. formed form the intermediate-diameter portion, the distal end surface of the medium diameter portion has a seat surface which can be adhered to the opening edge of the opening of the valve body, the capillary passage toward the rear side from the seat surface in the And a poppet in which a thick pipe line serving as a pressure chamber is formed behind the narrow pipe line,
Poppet urging means that presses the poppet and presses the seat surface of the tip against the opening edge of the opening of the valve body;
One of the poppets is connected to the pressure chamber side, the other is connected to the second port, and a throttle channel having a throttle part in the middle;
Composed of
The poppet biasing means is
A coil spring fitted into the hollow part of the valve body and the tip pressing the large diameter part of the poppet;
Screwed into the hollow part of the valve body, the head presses the rear end of the coil spring, and the tip of the shaft extending from the head is inserted into the thick pipe passage of the poppet and squeezed into the shaft. A pressure adjusting screw that forms a narrow tube path that becomes a part of the flow path and forms an orifice between the narrow tube path and the outer peripheral surface of the shaft;
Damping oil damper, characterized in that it is composed of. The vibration damper according to claim 1, wherein an accumulator is provided in the rod, and preload is applied to the oil by the accumulator . The damping oil damper according to claim 2, wherein a check valve is provided in the middle of a flow path communicating between the accumulator and the oil chamber, and an orifice is provided in the check valve .

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